// SPDX-License-Identifier: GPL-2.0-or-later /* * Security plug functions * * Copyright (C) 2001 WireX Communications, Inc * Copyright (C) 2001-2002 Greg Kroah-Hartman * Copyright (C) 2001 Networks Associates Technology, Inc * Copyright (C) 2016 Mellanox Technologies * Copyright (C) 2023 Microsoft Corporation */ #define pr_fmt(fmt) "LSM: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define SECURITY_HOOK_ACTIVE_KEY(HOOK, IDX) security_hook_active_##HOOK##_##IDX /* * Identifier for the LSM static calls. * HOOK is an LSM hook as defined in linux/lsm_hookdefs.h * IDX is the index of the static call. 0 <= NUM < MAX_LSM_COUNT */ #define LSM_STATIC_CALL(HOOK, IDX) lsm_static_call_##HOOK##_##IDX /* * Call the macro M for each LSM hook MAX_LSM_COUNT times. */ #define LSM_LOOP_UNROLL(M, ...) \ do { \ UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) \ } while (0) #define LSM_DEFINE_UNROLL(M, ...) UNROLL(MAX_LSM_COUNT, M, __VA_ARGS__) /* * These are descriptions of the reasons that can be passed to the * security_locked_down() LSM hook. Placing this array here allows * all security modules to use the same descriptions for auditing * purposes. */ const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { [LOCKDOWN_NONE] = "none", [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", [LOCKDOWN_KEXEC] = "kexec of unsigned images", [LOCKDOWN_HIBERNATION] = "hibernation", [LOCKDOWN_PCI_ACCESS] = "direct PCI access", [LOCKDOWN_IOPORT] = "raw io port access", [LOCKDOWN_MSR] = "raw MSR access", [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", [LOCKDOWN_MMIOTRACE] = "unsafe mmio", [LOCKDOWN_DEBUGFS] = "debugfs access", [LOCKDOWN_XMON_WR] = "xmon write access", [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", [LOCKDOWN_INTEGRITY_MAX] = "integrity", [LOCKDOWN_KCORE] = "/proc/kcore access", [LOCKDOWN_KPROBES] = "use of kprobes", [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", [LOCKDOWN_PERF] = "unsafe use of perf", [LOCKDOWN_TRACEFS] = "use of tracefs", [LOCKDOWN_XMON_RW] = "xmon read and write access", [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", }; static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain); static struct kmem_cache *lsm_file_cache; static struct kmem_cache *lsm_inode_cache; char *lsm_names; static struct lsm_blob_sizes blob_sizes __ro_after_init; /* Boot-time LSM user choice */ static __initdata const char *chosen_lsm_order; static __initdata const char *chosen_major_lsm; static __initconst const char *const builtin_lsm_order = CONFIG_LSM; /* Ordered list of LSMs to initialize. */ static __initdata struct lsm_info *ordered_lsms[MAX_LSM_COUNT + 1]; static __initdata struct lsm_info *exclusive; #ifdef CONFIG_HAVE_STATIC_CALL #define LSM_HOOK_TRAMP(NAME, NUM) \ &STATIC_CALL_TRAMP(LSM_STATIC_CALL(NAME, NUM)) #else #define LSM_HOOK_TRAMP(NAME, NUM) NULL #endif /* * Define static calls and static keys for each LSM hook. */ #define DEFINE_LSM_STATIC_CALL(NUM, NAME, RET, ...) \ DEFINE_STATIC_CALL_NULL(LSM_STATIC_CALL(NAME, NUM), \ *((RET(*)(__VA_ARGS__))NULL)); \ DEFINE_STATIC_KEY_FALSE(SECURITY_HOOK_ACTIVE_KEY(NAME, NUM)); #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ LSM_DEFINE_UNROLL(DEFINE_LSM_STATIC_CALL, NAME, RET, __VA_ARGS__) #include #undef LSM_HOOK #undef DEFINE_LSM_STATIC_CALL /* * Initialise a table of static calls for each LSM hook. * DEFINE_STATIC_CALL_NULL invocation above generates a key (STATIC_CALL_KEY) * and a trampoline (STATIC_CALL_TRAMP) which are used to call * __static_call_update when updating the static call. * * The static calls table is used by early LSMs, some architectures can fault on * unaligned accesses and the fault handling code may not be ready by then. * Thus, the static calls table should be aligned to avoid any unhandled faults * in early init. */ struct lsm_static_calls_table static_calls_table __ro_after_init __aligned(sizeof(u64)) = { #define INIT_LSM_STATIC_CALL(NUM, NAME) \ (struct lsm_static_call) { \ .key = &STATIC_CALL_KEY(LSM_STATIC_CALL(NAME, NUM)), \ .trampoline = LSM_HOOK_TRAMP(NAME, NUM), \ .active = &SECURITY_HOOK_ACTIVE_KEY(NAME, NUM), \ }, #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ .NAME = { \ LSM_DEFINE_UNROLL(INIT_LSM_STATIC_CALL, NAME) \ }, #include #undef LSM_HOOK #undef INIT_LSM_STATIC_CALL }; static __initdata bool debug; #define init_debug(...) \ do { \ if (debug) \ pr_info(__VA_ARGS__); \ } while (0) static bool __init is_enabled(struct lsm_info *lsm) { if (!lsm->enabled) return false; return *lsm->enabled; } /* Mark an LSM's enabled flag. */ static int lsm_enabled_true __initdata = 1; static int lsm_enabled_false __initdata = 0; static void __init set_enabled(struct lsm_info *lsm, bool enabled) { /* * When an LSM hasn't configured an enable variable, we can use * a hard-coded location for storing the default enabled state. */ if (!lsm->enabled) { if (enabled) lsm->enabled = &lsm_enabled_true; else lsm->enabled = &lsm_enabled_false; } else if (lsm->enabled == &lsm_enabled_true) { if (!enabled) lsm->enabled = &lsm_enabled_false; } else if (lsm->enabled == &lsm_enabled_false) { if (enabled) lsm->enabled = &lsm_enabled_true; } else { *lsm->enabled = enabled; } } /* Is an LSM already listed in the ordered LSMs list? */ static bool __init exists_ordered_lsm(struct lsm_info *lsm) { struct lsm_info **check; for (check = ordered_lsms; *check; check++) if (*check == lsm) return true; return false; } /* Append an LSM to the list of ordered LSMs to initialize. */ static int last_lsm __initdata; static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from) { /* Ignore duplicate selections. */ if (exists_ordered_lsm(lsm)) return; if (WARN(last_lsm == MAX_LSM_COUNT, "%s: out of LSM static calls!?\n", from)) return; /* Enable this LSM, if it is not already set. */ if (!lsm->enabled) lsm->enabled = &lsm_enabled_true; ordered_lsms[last_lsm++] = lsm; init_debug("%s ordered: %s (%s)\n", from, lsm->name, is_enabled(lsm) ? "enabled" : "disabled"); } /* Is an LSM allowed to be initialized? */ static bool __init lsm_allowed(struct lsm_info *lsm) { /* Skip if the LSM is disabled. */ if (!is_enabled(lsm)) return false; /* Not allowed if another exclusive LSM already initialized. */ if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) { init_debug("exclusive disabled: %s\n", lsm->name); return false; } return true; } static void __init lsm_set_blob_size(int *need, int *lbs) { int offset; if (*need <= 0) return; offset = ALIGN(*lbs, sizeof(void *)); *lbs = offset + *need; *need = offset; } static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) { if (!needed) return; lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred); lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file); lsm_set_blob_size(&needed->lbs_ib, &blob_sizes.lbs_ib); /* * The inode blob gets an rcu_head in addition to * what the modules might need. */ if (needed->lbs_inode && blob_sizes.lbs_inode == 0) blob_sizes.lbs_inode = sizeof(struct rcu_head); lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key); lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); lsm_set_blob_size(&needed->lbs_perf_event, &blob_sizes.lbs_perf_event); lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); lsm_set_blob_size(&needed->lbs_tun_dev, &blob_sizes.lbs_tun_dev); lsm_set_blob_size(&needed->lbs_xattr_count, &blob_sizes.lbs_xattr_count); lsm_set_blob_size(&needed->lbs_bdev, &blob_sizes.lbs_bdev); } /* Prepare LSM for initialization. */ static void __init prepare_lsm(struct lsm_info *lsm) { int enabled = lsm_allowed(lsm); /* Record enablement (to handle any following exclusive LSMs). */ set_enabled(lsm, enabled); /* If enabled, do pre-initialization work. */ if (enabled) { if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) { exclusive = lsm; init_debug("exclusive chosen: %s\n", lsm->name); } lsm_set_blob_sizes(lsm->blobs); } } /* Initialize a given LSM, if it is enabled. */ static void __init initialize_lsm(struct lsm_info *lsm) { if (is_enabled(lsm)) { int ret; init_debug("initializing %s\n", lsm->name); ret = lsm->init(); WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret); } } /* * Current index to use while initializing the lsm id list. */ u32 lsm_active_cnt __ro_after_init; const struct lsm_id *lsm_idlist[MAX_LSM_COUNT]; /* Populate ordered LSMs list from comma-separated LSM name list. */ static void __init ordered_lsm_parse(const char *order, const char *origin) { struct lsm_info *lsm; char *sep, *name, *next; /* LSM_ORDER_FIRST is always first. */ for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { if (lsm->order == LSM_ORDER_FIRST) append_ordered_lsm(lsm, " first"); } /* Process "security=", if given. */ if (chosen_major_lsm) { struct lsm_info *major; /* * To match the original "security=" behavior, this * explicitly does NOT fallback to another Legacy Major * if the selected one was separately disabled: disable * all non-matching Legacy Major LSMs. */ for (major = __start_lsm_info; major < __end_lsm_info; major++) { if ((major->flags & LSM_FLAG_LEGACY_MAJOR) && strcmp(major->name, chosen_major_lsm) != 0) { set_enabled(major, false); init_debug("security=%s disabled: %s (only one legacy major LSM)\n", chosen_major_lsm, major->name); } } } sep = kstrdup(order, GFP_KERNEL); next = sep; /* Walk the list, looking for matching LSMs. */ while ((name = strsep(&next, ",")) != NULL) { bool found = false; for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { if (strcmp(lsm->name, name) == 0) { if (lsm->order == LSM_ORDER_MUTABLE) append_ordered_lsm(lsm, origin); found = true; } } if (!found) init_debug("%s ignored: %s (not built into kernel)\n", origin, name); } /* Process "security=", if given. */ if (chosen_major_lsm) { for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { if (exists_ordered_lsm(lsm)) continue; if (strcmp(lsm->name, chosen_major_lsm) == 0) append_ordered_lsm(lsm, "security="); } } /* LSM_ORDER_LAST is always last. */ for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { if (lsm->order == LSM_ORDER_LAST) append_ordered_lsm(lsm, " last"); } /* Disable all LSMs not in the ordered list. */ for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { if (exists_ordered_lsm(lsm)) continue; set_enabled(lsm, false); init_debug("%s skipped: %s (not in requested order)\n", origin, lsm->name); } kfree(sep); } static void __init lsm_static_call_init(struct security_hook_list *hl) { struct lsm_static_call *scall = hl->scalls; int i; for (i = 0; i < MAX_LSM_COUNT; i++) { /* Update the first static call that is not used yet */ if (!scall->hl) { __static_call_update(scall->key, scall->trampoline, hl->hook.lsm_func_addr); scall->hl = hl; static_branch_enable(scall->active); return; } scall++; } panic("%s - Ran out of static slots.\n", __func__); } static void __init lsm_early_cred(struct cred *cred); static void __init lsm_early_task(struct task_struct *task); static int lsm_append(const char *new, char **result); static void __init report_lsm_order(void) { struct lsm_info **lsm, *early; int first = 0; pr_info("initializing lsm="); /* Report each enabled LSM name, comma separated. */ for (early = __start_early_lsm_info; early < __end_early_lsm_info; early++) if (is_enabled(early)) pr_cont("%s%s", first++ == 0 ? "" : ",", early->name); for (lsm = ordered_lsms; *lsm; lsm++) if (is_enabled(*lsm)) pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name); pr_cont("\n"); } static void __init ordered_lsm_init(void) { struct lsm_info **lsm; if (chosen_lsm_order) { if (chosen_major_lsm) { pr_warn("security=%s is ignored because it is superseded by lsm=%s\n", chosen_major_lsm, chosen_lsm_order); chosen_major_lsm = NULL; } ordered_lsm_parse(chosen_lsm_order, "cmdline"); } else ordered_lsm_parse(builtin_lsm_order, "builtin"); for (lsm = ordered_lsms; *lsm; lsm++) prepare_lsm(*lsm); report_lsm_order(); init_debug("cred blob size = %d\n", blob_sizes.lbs_cred); init_debug("file blob size = %d\n", blob_sizes.lbs_file); init_debug("ib blob size = %d\n", blob_sizes.lbs_ib); init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); #ifdef CONFIG_KEYS init_debug("key blob size = %d\n", blob_sizes.lbs_key); #endif /* CONFIG_KEYS */ init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event); init_debug("task blob size = %d\n", blob_sizes.lbs_task); init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev); init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count); init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev); /* * Create any kmem_caches needed for blobs */ if (blob_sizes.lbs_file) lsm_file_cache = kmem_cache_create("lsm_file_cache", blob_sizes.lbs_file, 0, SLAB_PANIC, NULL); if (blob_sizes.lbs_inode) lsm_inode_cache = kmem_cache_create("lsm_inode_cache", blob_sizes.lbs_inode, 0, SLAB_PANIC, NULL); lsm_early_cred((struct cred *) current->cred); lsm_early_task(current); for (lsm = ordered_lsms; *lsm; lsm++) initialize_lsm(*lsm); } int __init early_security_init(void) { struct lsm_info *lsm; for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { if (!lsm->enabled) lsm->enabled = &lsm_enabled_true; prepare_lsm(lsm); initialize_lsm(lsm); } return 0; } /** * security_init - initializes the security framework * * This should be called early in the kernel initialization sequence. */ int __init security_init(void) { struct lsm_info *lsm; init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*"); init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order); init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*"); /* * Append the names of the early LSM modules now that kmalloc() is * available */ for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { init_debug(" early started: %s (%s)\n", lsm->name, is_enabled(lsm) ? "enabled" : "disabled"); if (lsm->enabled) lsm_append(lsm->name, &lsm_names); } /* Load LSMs in specified order. */ ordered_lsm_init(); return 0; } /* Save user chosen LSM */ static int __init choose_major_lsm(char *str) { chosen_major_lsm = str; return 1; } __setup("security=", choose_major_lsm); /* Explicitly choose LSM initialization order. */ static int __init choose_lsm_order(char *str) { chosen_lsm_order = str; return 1; } __setup("lsm=", choose_lsm_order); /* Enable LSM order debugging. */ static int __init enable_debug(char *str) { debug = true; return 1; } __setup("lsm.debug", enable_debug); static bool match_last_lsm(const char *list, const char *lsm) { const char *last; if (WARN_ON(!list || !lsm)) return false; last = strrchr(list, ','); if (last) /* Pass the comma, strcmp() will check for '\0' */ last++; else last = list; return !strcmp(last, lsm); } static int lsm_append(const char *new, char **result) { char *cp; if (*result == NULL) { *result = kstrdup(new, GFP_KERNEL); if (*result == NULL) return -ENOMEM; } else { /* Check if it is the last registered name */ if (match_last_lsm(*result, new)) return 0; cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new); if (cp == NULL) return -ENOMEM; kfree(*result); *result = cp; } return 0; } /** * security_add_hooks - Add a modules hooks to the hook lists. * @hooks: the hooks to add * @count: the number of hooks to add * @lsmid: the identification information for the security module * * Each LSM has to register its hooks with the infrastructure. */ void __init security_add_hooks(struct security_hook_list *hooks, int count, const struct lsm_id *lsmid) { int i; /* * A security module may call security_add_hooks() more * than once during initialization, and LSM initialization * is serialized. Landlock is one such case. * Look at the previous entry, if there is one, for duplication. */ if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) { if (lsm_active_cnt >= MAX_LSM_COUNT) panic("%s Too many LSMs registered.\n", __func__); lsm_idlist[lsm_active_cnt++] = lsmid; } for (i = 0; i < count; i++) { hooks[i].lsmid = lsmid; lsm_static_call_init(&hooks[i]); } /* * Don't try to append during early_security_init(), we'll come back * and fix this up afterwards. */ if (slab_is_available()) { if (lsm_append(lsmid->name, &lsm_names) < 0) panic("%s - Cannot get early memory.\n", __func__); } } int call_blocking_lsm_notifier(enum lsm_event event, void *data) { return blocking_notifier_call_chain(&blocking_lsm_notifier_chain, event, data); } EXPORT_SYMBOL(call_blocking_lsm_notifier); int register_blocking_lsm_notifier(struct notifier_block *nb) { return blocking_notifier_chain_register(&blocking_lsm_notifier_chain, nb); } EXPORT_SYMBOL(register_blocking_lsm_notifier); int unregister_blocking_lsm_notifier(struct notifier_block *nb) { return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain, nb); } EXPORT_SYMBOL(unregister_blocking_lsm_notifier); /** * lsm_blob_alloc - allocate a composite blob * @dest: the destination for the blob * @size: the size of the blob * @gfp: allocation type * * Allocate a blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_blob_alloc(void **dest, size_t size, gfp_t gfp) { if (size == 0) { *dest = NULL; return 0; } *dest = kzalloc(size, gfp); if (*dest == NULL) return -ENOMEM; return 0; } /** * lsm_cred_alloc - allocate a composite cred blob * @cred: the cred that needs a blob * @gfp: allocation type * * Allocate the cred blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_cred_alloc(struct cred *cred, gfp_t gfp) { return lsm_blob_alloc(&cred->security, blob_sizes.lbs_cred, gfp); } /** * lsm_early_cred - during initialization allocate a composite cred blob * @cred: the cred that needs a blob * * Allocate the cred blob for all the modules */ static void __init lsm_early_cred(struct cred *cred) { int rc = lsm_cred_alloc(cred, GFP_KERNEL); if (rc) panic("%s: Early cred alloc failed.\n", __func__); } /** * lsm_file_alloc - allocate a composite file blob * @file: the file that needs a blob * * Allocate the file blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_file_alloc(struct file *file) { if (!lsm_file_cache) { file->f_security = NULL; return 0; } file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); if (file->f_security == NULL) return -ENOMEM; return 0; } /** * lsm_inode_alloc - allocate a composite inode blob * @inode: the inode that needs a blob * @gfp: allocation flags * * Allocate the inode blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_inode_alloc(struct inode *inode, gfp_t gfp) { if (!lsm_inode_cache) { inode->i_security = NULL; return 0; } inode->i_security = kmem_cache_zalloc(lsm_inode_cache, gfp); if (inode->i_security == NULL) return -ENOMEM; return 0; } /** * lsm_task_alloc - allocate a composite task blob * @task: the task that needs a blob * * Allocate the task blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_task_alloc(struct task_struct *task) { return lsm_blob_alloc(&task->security, blob_sizes.lbs_task, GFP_KERNEL); } /** * lsm_ipc_alloc - allocate a composite ipc blob * @kip: the ipc that needs a blob * * Allocate the ipc blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_ipc_alloc(struct kern_ipc_perm *kip) { return lsm_blob_alloc(&kip->security, blob_sizes.lbs_ipc, GFP_KERNEL); } #ifdef CONFIG_KEYS /** * lsm_key_alloc - allocate a composite key blob * @key: the key that needs a blob * * Allocate the key blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_key_alloc(struct key *key) { return lsm_blob_alloc(&key->security, blob_sizes.lbs_key, GFP_KERNEL); } #endif /* CONFIG_KEYS */ /** * lsm_msg_msg_alloc - allocate a composite msg_msg blob * @mp: the msg_msg that needs a blob * * Allocate the ipc blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_msg_msg_alloc(struct msg_msg *mp) { return lsm_blob_alloc(&mp->security, blob_sizes.lbs_msg_msg, GFP_KERNEL); } /** * lsm_bdev_alloc - allocate a composite block_device blob * @bdev: the block_device that needs a blob * * Allocate the block_device blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_bdev_alloc(struct block_device *bdev) { if (blob_sizes.lbs_bdev == 0) { bdev->bd_security = NULL; return 0; } bdev->bd_security = kzalloc(blob_sizes.lbs_bdev, GFP_KERNEL); if (!bdev->bd_security) return -ENOMEM; return 0; } /** * lsm_early_task - during initialization allocate a composite task blob * @task: the task that needs a blob * * Allocate the task blob for all the modules */ static void __init lsm_early_task(struct task_struct *task) { int rc = lsm_task_alloc(task); if (rc) panic("%s: Early task alloc failed.\n", __func__); } /** * lsm_superblock_alloc - allocate a composite superblock blob * @sb: the superblock that needs a blob * * Allocate the superblock blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_superblock_alloc(struct super_block *sb) { return lsm_blob_alloc(&sb->s_security, blob_sizes.lbs_superblock, GFP_KERNEL); } /** * lsm_fill_user_ctx - Fill a user space lsm_ctx structure * @uctx: a userspace LSM context to be filled * @uctx_len: available uctx size (input), used uctx size (output) * @val: the new LSM context value * @val_len: the size of the new LSM context value * @id: LSM id * @flags: LSM defined flags * * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL * simply calculate the required size to output via @utc_len and return * success. * * Returns 0 on success, -E2BIG if userspace buffer is not large enough, * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. */ int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, void *val, size_t val_len, u64 id, u64 flags) { struct lsm_ctx *nctx = NULL; size_t nctx_len; int rc = 0; nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *)); if (nctx_len > *uctx_len) { rc = -E2BIG; goto out; } /* no buffer - return success/0 and set @uctx_len to the req size */ if (!uctx) goto out; nctx = kzalloc(nctx_len, GFP_KERNEL); if (nctx == NULL) { rc = -ENOMEM; goto out; } nctx->id = id; nctx->flags = flags; nctx->len = nctx_len; nctx->ctx_len = val_len; memcpy(nctx->ctx, val, val_len); if (copy_to_user(uctx, nctx, nctx_len)) rc = -EFAULT; out: kfree(nctx); *uctx_len = nctx_len; return rc; } /* * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and * can be accessed with: * * LSM_RET_DEFAULT() * * The macros below define static constants for the default value of each * LSM hook. */ #define LSM_RET_DEFAULT(NAME) (NAME##_default) #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME) #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \ static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT); #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME) #include #undef LSM_HOOK /* * Hook list operation macros. * * call_void_hook: * This is a hook that does not return a value. * * call_int_hook: * This is a hook that returns a value. */ #define __CALL_STATIC_VOID(NUM, HOOK, ...) \ do { \ if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ } \ } while (0); #define call_void_hook(HOOK, ...) \ do { \ LSM_LOOP_UNROLL(__CALL_STATIC_VOID, HOOK, __VA_ARGS__); \ } while (0) #define __CALL_STATIC_INT(NUM, R, HOOK, LABEL, ...) \ do { \ if (static_branch_unlikely(&SECURITY_HOOK_ACTIVE_KEY(HOOK, NUM))) { \ R = static_call(LSM_STATIC_CALL(HOOK, NUM))(__VA_ARGS__); \ if (R != LSM_RET_DEFAULT(HOOK)) \ goto LABEL; \ } \ } while (0); #define call_int_hook(HOOK, ...) \ ({ \ __label__ OUT; \ int RC = LSM_RET_DEFAULT(HOOK); \ \ LSM_LOOP_UNROLL(__CALL_STATIC_INT, RC, HOOK, OUT, __VA_ARGS__); \ OUT: \ RC; \ }) #define lsm_for_each_hook(scall, NAME) \ for (scall = static_calls_table.NAME; \ scall - static_calls_table.NAME < MAX_LSM_COUNT; scall++) \ if (static_key_enabled(&scall->active->key)) /* Security operations */ /** * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok * @mgr: task credentials of current binder process * * Check whether @mgr is allowed to be the binder context manager. * * Return: Return 0 if permission is granted. */ int security_binder_set_context_mgr(const struct cred *mgr) { return call_int_hook(binder_set_context_mgr, mgr); } /** * security_binder_transaction() - Check if a binder transaction is allowed * @from: sending process * @to: receiving process * * Check whether @from is allowed to invoke a binder transaction call to @to. * * Return: Returns 0 if permission is granted. */ int security_binder_transaction(const struct cred *from, const struct cred *to) { return call_int_hook(binder_transaction, from, to); } /** * security_binder_transfer_binder() - Check if a binder transfer is allowed * @from: sending process * @to: receiving process * * Check whether @from is allowed to transfer a binder reference to @to. * * Return: Returns 0 if permission is granted. */ int security_binder_transfer_binder(const struct cred *from, const struct cred *to) { return call_int_hook(binder_transfer_binder, from, to); } /** * security_binder_transfer_file() - Check if a binder file xfer is allowed * @from: sending process * @to: receiving process * @file: file being transferred * * Check whether @from is allowed to transfer @file to @to. * * Return: Returns 0 if permission is granted. */ int security_binder_transfer_file(const struct cred *from, const struct cred *to, const struct file *file) { return call_int_hook(binder_transfer_file, from, to, file); } /** * security_ptrace_access_check() - Check if tracing is allowed * @child: target process * @mode: PTRACE_MODE flags * * Check permission before allowing the current process to trace the @child * process. Security modules may also want to perform a process tracing check * during an execve in the set_security or apply_creds hooks of tracing check * during an execve in the bprm_set_creds hook of binprm_security_ops if the * process is being traced and its security attributes would be changed by the * execve. * * Return: Returns 0 if permission is granted. */ int security_ptrace_access_check(struct task_struct *child, unsigned int mode) { return call_int_hook(ptrace_access_check, child, mode); } /** * security_ptrace_traceme() - Check if tracing is allowed * @parent: tracing process * * Check that the @parent process has sufficient permission to trace the * current process before allowing the current process to present itself to the * @parent process for tracing. * * Return: Returns 0 if permission is granted. */ int security_ptrace_traceme(struct task_struct *parent) { return call_int_hook(ptrace_traceme, parent); } /** * security_capget() - Get the capability sets for a process * @target: target process * @effective: effective capability set * @inheritable: inheritable capability set * @permitted: permitted capability set * * Get the @effective, @inheritable, and @permitted capability sets for the * @target process. The hook may also perform permission checking to determine * if the current process is allowed to see the capability sets of the @target * process. * * Return: Returns 0 if the capability sets were successfully obtained. */ int security_capget(const struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted) { return call_int_hook(capget, target, effective, inheritable, permitted); } /** * security_capset() - Set the capability sets for a process * @new: new credentials for the target process * @old: current credentials of the target process * @effective: effective capability set * @inheritable: inheritable capability set * @permitted: permitted capability set * * Set the @effective, @inheritable, and @permitted capability sets for the * current process. * * Return: Returns 0 and update @new if permission is granted. */ int security_capset(struct cred *new, const struct cred *old, const kernel_cap_t *effective, const kernel_cap_t *inheritable, const kernel_cap_t *permitted) { return call_int_hook(capset, new, old, effective, inheritable, permitted); } /** * security_capable() - Check if a process has the necessary capability * @cred: credentials to examine * @ns: user namespace * @cap: capability requested * @opts: capability check options * * Check whether the @tsk process has the @cap capability in the indicated * credentials. @cap contains the capability . * @opts contains options for the capable check . * * Return: Returns 0 if the capability is granted. */ int security_capable(const struct cred *cred, struct user_namespace *ns, int cap, unsigned int opts) { return call_int_hook(capable, cred, ns, cap, opts); } /** * security_quotactl() - Check if a quotactl() syscall is allowed for this fs * @cmds: commands * @type: type * @id: id * @sb: filesystem * * Check whether the quotactl syscall is allowed for this @sb. * * Return: Returns 0 if permission is granted. */ int security_quotactl(int cmds, int type, int id, const struct super_block *sb) { return call_int_hook(quotactl, cmds, type, id, sb); } /** * security_quota_on() - Check if QUOTAON is allowed for a dentry * @dentry: dentry * * Check whether QUOTAON is allowed for @dentry. * * Return: Returns 0 if permission is granted. */ int security_quota_on(struct dentry *dentry) { return call_int_hook(quota_on, dentry); } /** * security_syslog() - Check if accessing the kernel message ring is allowed * @type: SYSLOG_ACTION_* type * * Check permission before accessing the kernel message ring or changing * logging to the console. See the syslog(2) manual page for an explanation of * the @type values. * * Return: Return 0 if permission is granted. */ int security_syslog(int type) { return call_int_hook(syslog, type); } /** * security_settime64() - Check if changing the system time is allowed * @ts: new time * @tz: timezone * * Check permission to change the system time, struct timespec64 is defined in * and timezone is defined in . * * Return: Returns 0 if permission is granted. */ int security_settime64(const struct timespec64 *ts, const struct timezone *tz) { return call_int_hook(settime, ts, tz); } /** * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed * @mm: mm struct * @pages: number of pages * * Check permissions for allocating a new virtual mapping. If all LSMs return * a positive value, __vm_enough_memory() will be called with cap_sys_admin * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be * called with cap_sys_admin cleared. * * Return: Returns 0 if permission is granted by the LSM infrastructure to the * caller. */ int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) { struct lsm_static_call *scall; int cap_sys_admin = 1; int rc; /* * The module will respond with 0 if it thinks the __vm_enough_memory() * call should be made with the cap_sys_admin set. If all of the modules * agree that it should be set it will. If any module thinks it should * not be set it won't. */ lsm_for_each_hook(scall, vm_enough_memory) { rc = scall->hl->hook.vm_enough_memory(mm, pages); if (rc < 0) { cap_sys_admin = 0; break; } } return __vm_enough_memory(mm, pages, cap_sys_admin); } /** * security_bprm_creds_for_exec() - Prepare the credentials for exec() * @bprm: binary program information * * If the setup in prepare_exec_creds did not setup @bprm->cred->security * properly for executing @bprm->file, update the LSM's portion of * @bprm->cred->security to be what commit_creds needs to install for the new * program. This hook may also optionally check permissions (e.g. for * transitions between security domains). The hook must set @bprm->secureexec * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm * contains the linux_binprm structure. * * Return: Returns 0 if the hook is successful and permission is granted. */ int security_bprm_creds_for_exec(struct linux_binprm *bprm) { return call_int_hook(bprm_creds_for_exec, bprm); } /** * security_bprm_creds_from_file() - Update linux_binprm creds based on file * @bprm: binary program information * @file: associated file * * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon * exec, update @bprm->cred to reflect that change. This is called after * finding the binary that will be executed without an interpreter. This * ensures that the credentials will not be derived from a script that the * binary will need to reopen, which when reopend may end up being a completely * different file. This hook may also optionally check permissions (e.g. for * transitions between security domains). The hook must set @bprm->secureexec * to 1 if AT_SECURE should be set to request libc enable secure mode. The * hook must add to @bprm->per_clear any personality flags that should be * cleared from current->personality. @bprm contains the linux_binprm * structure. * * Return: Returns 0 if the hook is successful and permission is granted. */ int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) { return call_int_hook(bprm_creds_from_file, bprm, file); } /** * security_bprm_check() - Mediate binary handler search * @bprm: binary program information * * This hook mediates the point when a search for a binary handler will begin. * It allows a check against the @bprm->cred->security value which was set in * the preceding creds_for_exec call. The argv list and envp list are reliably * available in @bprm. This hook may be called multiple times during a single * execve. @bprm contains the linux_binprm structure. * * Return: Returns 0 if the hook is successful and permission is granted. */ int security_bprm_check(struct linux_binprm *bprm) { return call_int_hook(bprm_check_security, bprm); } /** * security_bprm_committing_creds() - Install creds for a process during exec() * @bprm: binary program information * * Prepare to install the new security attributes of a process being * transformed by an execve operation, based on the old credentials pointed to * by @current->cred and the information set in @bprm->cred by the * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This * hook is a good place to perform state changes on the process such as closing * open file descriptors to which access will no longer be granted when the * attributes are changed. This is called immediately before commit_creds(). */ void security_bprm_committing_creds(const struct linux_binprm *bprm) { call_void_hook(bprm_committing_creds, bprm); } /** * security_bprm_committed_creds() - Tidy up after cred install during exec() * @bprm: binary program information * * Tidy up after the installation of the new security attributes of a process * being transformed by an execve operation. The new credentials have, by this * point, been set to @current->cred. @bprm points to the linux_binprm * structure. This hook is a good place to perform state changes on the * process such as clearing out non-inheritable signal state. This is called * immediately after commit_creds(). */ void security_bprm_committed_creds(const struct linux_binprm *bprm) { call_void_hook(bprm_committed_creds, bprm); } /** * security_fs_context_submount() - Initialise fc->security * @fc: new filesystem context * @reference: dentry reference for submount/remount * * Fill out the ->security field for a new fs_context. * * Return: Returns 0 on success or negative error code on failure. */ int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) { return call_int_hook(fs_context_submount, fc, reference); } /** * security_fs_context_dup() - Duplicate a fs_context LSM blob * @fc: destination filesystem context * @src_fc: source filesystem context * * Allocate and attach a security structure to sc->security. This pointer is * initialised to NULL by the caller. @fc indicates the new filesystem context. * @src_fc indicates the original filesystem context. * * Return: Returns 0 on success or a negative error code on failure. */ int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) { return call_int_hook(fs_context_dup, fc, src_fc); } /** * security_fs_context_parse_param() - Configure a filesystem context * @fc: filesystem context * @param: filesystem parameter * * Userspace provided a parameter to configure a superblock. The LSM can * consume the parameter or return it to the caller for use elsewhere. * * Return: If the parameter is used by the LSM it should return 0, if it is * returned to the caller -ENOPARAM is returned, otherwise a negative * error code is returned. */ int security_fs_context_parse_param(struct fs_context *fc, struct fs_parameter *param) { struct lsm_static_call *scall; int trc; int rc = -ENOPARAM; lsm_for_each_hook(scall, fs_context_parse_param) { trc = scall->hl->hook.fs_context_parse_param(fc, param); if (trc == 0) rc = 0; else if (trc != -ENOPARAM) return trc; } return rc; } /** * security_sb_alloc() - Allocate a super_block LSM blob * @sb: filesystem superblock * * Allocate and attach a security structure to the sb->s_security field. The * s_security field is initialized to NULL when the structure is allocated. * @sb contains the super_block structure to be modified. * * Return: Returns 0 if operation was successful. */ int security_sb_alloc(struct super_block *sb) { int rc = lsm_superblock_alloc(sb); if (unlikely(rc)) return rc; rc = call_int_hook(sb_alloc_security, sb); if (unlikely(rc)) security_sb_free(sb); return rc; } /** * security_sb_delete() - Release super_block LSM associated objects * @sb: filesystem superblock * * Release objects tied to a superblock (e.g. inodes). @sb contains the * super_block structure being released. */ void security_sb_delete(struct super_block *sb) { call_void_hook(sb_delete, sb); } /** * security_sb_free() - Free a super_block LSM blob * @sb: filesystem superblock * * Deallocate and clear the sb->s_security field. @sb contains the super_block * structure to be modified. */ void security_sb_free(struct super_block *sb) { call_void_hook(sb_free_security, sb); kfree(sb->s_security); sb->s_security = NULL; } /** * security_free_mnt_opts() - Free memory associated with mount options * @mnt_opts: LSM processed mount options * * Free memory associated with @mnt_ops. */ void security_free_mnt_opts(void **mnt_opts) { if (!*mnt_opts) return; call_void_hook(sb_free_mnt_opts, *mnt_opts); *mnt_opts = NULL; } EXPORT_SYMBOL(security_free_mnt_opts); /** * security_sb_eat_lsm_opts() - Consume LSM mount options * @options: mount options * @mnt_opts: LSM processed mount options * * Eat (scan @options) and save them in @mnt_opts. * * Return: Returns 0 on success, negative values on failure. */ int security_sb_eat_lsm_opts(char *options, void **mnt_opts) { return call_int_hook(sb_eat_lsm_opts, options, mnt_opts); } EXPORT_SYMBOL(security_sb_eat_lsm_opts); /** * security_sb_mnt_opts_compat() - Check if new mount options are allowed * @sb: filesystem superblock * @mnt_opts: new mount options * * Determine if the new mount options in @mnt_opts are allowed given the * existing mounted filesystem at @sb. @sb superblock being compared. * * Return: Returns 0 if options are compatible. */ int security_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) { return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts); } EXPORT_SYMBOL(security_sb_mnt_opts_compat); /** * security_sb_remount() - Verify no incompatible mount changes during remount * @sb: filesystem superblock * @mnt_opts: (re)mount options * * Extracts security system specific mount options and verifies no changes are * being made to those options. * * Return: Returns 0 if permission is granted. */ int security_sb_remount(struct super_block *sb, void *mnt_opts) { return call_int_hook(sb_remount, sb, mnt_opts); } EXPORT_SYMBOL(security_sb_remount); /** * security_sb_kern_mount() - Check if a kernel mount is allowed * @sb: filesystem superblock * * Mount this @sb if allowed by permissions. * * Return: Returns 0 if permission is granted. */ int security_sb_kern_mount(const struct super_block *sb) { return call_int_hook(sb_kern_mount, sb); } /** * security_sb_show_options() - Output the mount options for a superblock * @m: output file * @sb: filesystem superblock * * Show (print on @m) mount options for this @sb. * * Return: Returns 0 on success, negative values on failure. */ int security_sb_show_options(struct seq_file *m, struct super_block *sb) { return call_int_hook(sb_show_options, m, sb); } /** * security_sb_statfs() - Check if accessing fs stats is allowed * @dentry: superblock handle * * Check permission before obtaining filesystem statistics for the @mnt * mountpoint. @dentry is a handle on the superblock for the filesystem. * * Return: Returns 0 if permission is granted. */ int security_sb_statfs(struct dentry *dentry) { return call_int_hook(sb_statfs, dentry); } /** * security_sb_mount() - Check permission for mounting a filesystem * @dev_name: filesystem backing device * @path: mount point * @type: filesystem type * @flags: mount flags * @data: filesystem specific data * * Check permission before an object specified by @dev_name is mounted on the * mount point named by @nd. For an ordinary mount, @dev_name identifies a * device if the file system type requires a device. For a remount * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount * (@flags & MS_BIND), @dev_name identifies the pathname of the object being * mounted. * * Return: Returns 0 if permission is granted. */ int security_sb_mount(const char *dev_name, const struct path *path, const char *type, unsigned long flags, void *data) { return call_int_hook(sb_mount, dev_name, path, type, flags, data); } /** * security_sb_umount() - Check permission for unmounting a filesystem * @mnt: mounted filesystem * @flags: unmount flags * * Check permission before the @mnt file system is unmounted. * * Return: Returns 0 if permission is granted. */ int security_sb_umount(struct vfsmount *mnt, int flags) { return call_int_hook(sb_umount, mnt, flags); } /** * security_sb_pivotroot() - Check permissions for pivoting the rootfs * @old_path: new location for current rootfs * @new_path: location of the new rootfs * * Check permission before pivoting the root filesystem. * * Return: Returns 0 if permission is granted. */ int security_sb_pivotroot(const struct path *old_path, const struct path *new_path) { return call_int_hook(sb_pivotroot, old_path, new_path); } /** * security_sb_set_mnt_opts() - Set the mount options for a filesystem * @sb: filesystem superblock * @mnt_opts: binary mount options * @kern_flags: kernel flags (in) * @set_kern_flags: kernel flags (out) * * Set the security relevant mount options used for a superblock. * * Return: Returns 0 on success, error on failure. */ int security_sb_set_mnt_opts(struct super_block *sb, void *mnt_opts, unsigned long kern_flags, unsigned long *set_kern_flags) { struct lsm_static_call *scall; int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts); lsm_for_each_hook(scall, sb_set_mnt_opts) { rc = scall->hl->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags, set_kern_flags); if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts)) break; } return rc; } EXPORT_SYMBOL(security_sb_set_mnt_opts); /** * security_sb_clone_mnt_opts() - Duplicate superblock mount options * @oldsb: source superblock * @newsb: destination superblock * @kern_flags: kernel flags (in) * @set_kern_flags: kernel flags (out) * * Copy all security options from a given superblock to another. * * Return: Returns 0 on success, error on failure. */ int security_sb_clone_mnt_opts(const struct super_block *oldsb, struct super_block *newsb, unsigned long kern_flags, unsigned long *set_kern_flags) { return call_int_hook(sb_clone_mnt_opts, oldsb, newsb, kern_flags, set_kern_flags); } EXPORT_SYMBOL(security_sb_clone_mnt_opts); /** * security_move_mount() - Check permissions for moving a mount * @from_path: source mount point * @to_path: destination mount point * * Check permission before a mount is moved. * * Return: Returns 0 if permission is granted. */ int security_move_mount(const struct path *from_path, const struct path *to_path) { return call_int_hook(move_mount, from_path, to_path); } /** * security_path_notify() - Check if setting a watch is allowed * @path: file path * @mask: event mask * @obj_type: file path type * * Check permissions before setting a watch on events as defined by @mask, on * an object at @path, whose type is defined by @obj_type. * * Return: Returns 0 if permission is granted. */ int security_path_notify(const struct path *path, u64 mask, unsigned int obj_type) { return call_int_hook(path_notify, path, mask, obj_type); } /** * security_inode_alloc() - Allocate an inode LSM blob * @inode: the inode * @gfp: allocation flags * * Allocate and attach a security structure to @inode->i_security. The * i_security field is initialized to NULL when the inode structure is * allocated. * * Return: Return 0 if operation was successful. */ int security_inode_alloc(struct inode *inode, gfp_t gfp) { int rc = lsm_inode_alloc(inode, gfp); if (unlikely(rc)) return rc; rc = call_int_hook(inode_alloc_security, inode); if (unlikely(rc)) security_inode_free(inode); return rc; } static void inode_free_by_rcu(struct rcu_head *head) { /* The rcu head is at the start of the inode blob */ call_void_hook(inode_free_security_rcu, head); kmem_cache_free(lsm_inode_cache, head); } /** * security_inode_free() - Free an inode's LSM blob * @inode: the inode * * Release any LSM resources associated with @inode, although due to the * inode's RCU protections it is possible that the resources will not be * fully released until after the current RCU grace period has elapsed. * * It is important for LSMs to note that despite being present in a call to * security_inode_free(), @inode may still be referenced in a VFS path walk * and calls to security_inode_permission() may be made during, or after, * a call to security_inode_free(). For this reason the inode->i_security * field is released via a call_rcu() callback and any LSMs which need to * retain inode state for use in security_inode_permission() should only * release that state in the inode_free_security_rcu() LSM hook callback. */ void security_inode_free(struct inode *inode) { call_void_hook(inode_free_security, inode); if (!inode->i_security) return; call_rcu((struct rcu_head *)inode->i_security, inode_free_by_rcu); } /** * security_dentry_init_security() - Perform dentry initialization * @dentry: the dentry to initialize * @mode: mode used to determine resource type * @name: name of the last path component * @xattr_name: name of the security/LSM xattr * @ctx: pointer to the resulting LSM context * @ctxlen: length of @ctx * * Compute a context for a dentry as the inode is not yet available since NFSv4 * has no label backed by an EA anyway. It is important to note that * @xattr_name does not need to be free'd by the caller, it is a static string. * * Return: Returns 0 on success, negative values on failure. */ int security_dentry_init_security(struct dentry *dentry, int mode, const struct qstr *name, const char **xattr_name, void **ctx, u32 *ctxlen) { return call_int_hook(dentry_init_security, dentry, mode, name, xattr_name, ctx, ctxlen); } EXPORT_SYMBOL(security_dentry_init_security); /** * security_dentry_create_files_as() - Perform dentry initialization * @dentry: the dentry to initialize * @mode: mode used to determine resource type * @name: name of the last path component * @old: creds to use for LSM context calculations * @new: creds to modify * * Compute a context for a dentry as the inode is not yet available and set * that context in passed in creds so that new files are created using that * context. Context is calculated using the passed in creds and not the creds * of the caller. * * Return: Returns 0 on success, error on failure. */ int security_dentry_create_files_as(struct dentry *dentry, int mode, struct qstr *name, const struct cred *old, struct cred *new) { return call_int_hook(dentry_create_files_as, dentry, mode, name, old, new); } EXPORT_SYMBOL(security_dentry_create_files_as); /** * security_inode_init_security() - Initialize an inode's LSM context * @inode: the inode * @dir: parent directory * @qstr: last component of the pathname * @initxattrs: callback function to write xattrs * @fs_data: filesystem specific data * * Obtain the security attribute name suffix and value to set on a newly * created inode and set up the incore security field for the new inode. This * hook is called by the fs code as part of the inode creation transaction and * provides for atomic labeling of the inode, unlike the post_create/mkdir/... * hooks called by the VFS. * * The hook function is expected to populate the xattrs array, by calling * lsm_get_xattr_slot() to retrieve the slots reserved by the security module * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each * slot, the hook function should set ->name to the attribute name suffix * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it * to the attribute value, to set ->value_len to the length of the value. If * the security module does not use security attributes or does not wish to put * a security attribute on this particular inode, then it should return * -EOPNOTSUPP to skip this processing. * * Return: Returns 0 if the LSM successfully initialized all of the inode * security attributes that are required, negative values otherwise. */ int security_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, const initxattrs initxattrs, void *fs_data) { struct lsm_static_call *scall; struct xattr *new_xattrs = NULL; int ret = -EOPNOTSUPP, xattr_count = 0; if (unlikely(IS_PRIVATE(inode))) return 0; if (!blob_sizes.lbs_xattr_count) return 0; if (initxattrs) { /* Allocate +1 as terminator. */ new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, sizeof(*new_xattrs), GFP_NOFS); if (!new_xattrs) return -ENOMEM; } lsm_for_each_hook(scall, inode_init_security) { ret = scall->hl->hook.inode_init_security(inode, dir, qstr, new_xattrs, &xattr_count); if (ret && ret != -EOPNOTSUPP) goto out; /* * As documented in lsm_hooks.h, -EOPNOTSUPP in this context * means that the LSM is not willing to provide an xattr, not * that it wants to signal an error. Thus, continue to invoke * the remaining LSMs. */ } /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ if (!xattr_count) goto out; ret = initxattrs(inode, new_xattrs, fs_data); out: for (; xattr_count > 0; xattr_count--) kfree(new_xattrs[xattr_count - 1].value); kfree(new_xattrs); return (ret == -EOPNOTSUPP) ? 0 : ret; } EXPORT_SYMBOL(security_inode_init_security); /** * security_inode_init_security_anon() - Initialize an anonymous inode * @inode: the inode * @name: the anonymous inode class * @context_inode: an optional related inode * * Set up the incore security field for the new anonymous inode and return * whether the inode creation is permitted by the security module or not. * * Return: Returns 0 on success, -EACCES if the security module denies the * creation of this inode, or another -errno upon other errors. */ int security_inode_init_security_anon(struct inode *inode, const struct qstr *name, const struct inode *context_inode) { return call_int_hook(inode_init_security_anon, inode, name, context_inode); } #ifdef CONFIG_SECURITY_PATH /** * security_path_mknod() - Check if creating a special file is allowed * @dir: parent directory * @dentry: new file * @mode: new file mode * @dev: device number * * Check permissions when creating a file. Note that this hook is called even * if mknod operation is being done for a regular file. * * Return: Returns 0 if permission is granted. */ int security_path_mknod(const struct path *dir, struct dentry *dentry, umode_t mode, unsigned int dev) { if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) return 0; return call_int_hook(path_mknod, dir, dentry, mode, dev); } EXPORT_SYMBOL(security_path_mknod); /** * security_path_post_mknod() - Update inode security after reg file creation * @idmap: idmap of the mount * @dentry: new file * * Update inode security field after a regular file has been created. */ void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return; call_void_hook(path_post_mknod, idmap, dentry); } /** * security_path_mkdir() - Check if creating a new directory is allowed * @dir: parent directory * @dentry: new directory * @mode: new directory mode * * Check permissions to create a new directory in the existing directory. * * Return: Returns 0 if permission is granted. */ int security_path_mkdir(const struct path *dir, struct dentry *dentry, umode_t mode) { if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) return 0; return call_int_hook(path_mkdir, dir, dentry, mode); } EXPORT_SYMBOL(security_path_mkdir); /** * security_path_rmdir() - Check if removing a directory is allowed * @dir: parent directory * @dentry: directory to remove * * Check the permission to remove a directory. * * Return: Returns 0 if permission is granted. */ int security_path_rmdir(const struct path *dir, struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) return 0; return call_int_hook(path_rmdir, dir, dentry); } /** * security_path_unlink() - Check if removing a hard link is allowed * @dir: parent directory * @dentry: file * * Check the permission to remove a hard link to a file. * * Return: Returns 0 if permission is granted. */ int security_path_unlink(const struct path *dir, struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) return 0; return call_int_hook(path_unlink, dir, dentry); } EXPORT_SYMBOL(security_path_unlink); /** * security_path_symlink() - Check if creating a symbolic link is allowed * @dir: parent directory * @dentry: symbolic link * @old_name: file pathname * * Check the permission to create a symbolic link to a file. * * Return: Returns 0 if permission is granted. */ int security_path_symlink(const struct path *dir, struct dentry *dentry, const char *old_name) { if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) return 0; return call_int_hook(path_symlink, dir, dentry, old_name); } /** * security_path_link - Check if creating a hard link is allowed * @old_dentry: existing file * @new_dir: new parent directory * @new_dentry: new link * * Check permission before creating a new hard link to a file. * * Return: Returns 0 if permission is granted. */ int security_path_link(struct dentry *old_dentry, const struct path *new_dir, struct dentry *new_dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) return 0; return call_int_hook(path_link, old_dentry, new_dir, new_dentry); } /** * security_path_rename() - Check if renaming a file is allowed * @old_dir: parent directory of the old file * @old_dentry: the old file * @new_dir: parent directory of the new file * @new_dentry: the new file * @flags: flags * * Check for permission to rename a file or directory. * * Return: Returns 0 if permission is granted. */ int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, const struct path *new_dir, struct dentry *new_dentry, unsigned int flags) { if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || (d_is_positive(new_dentry) && IS_PRIVATE(d_backing_inode(new_dentry))))) return 0; return call_int_hook(path_rename, old_dir, old_dentry, new_dir, new_dentry, flags); } EXPORT_SYMBOL(security_path_rename); /** * security_path_truncate() - Check if truncating a file is allowed * @path: file * * Check permission before truncating the file indicated by path. Note that * truncation permissions may also be checked based on already opened files, * using the security_file_truncate() hook. * * Return: Returns 0 if permission is granted. */ int security_path_truncate(const struct path *path) { if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) return 0; return call_int_hook(path_truncate, path); } /** * security_path_chmod() - Check if changing the file's mode is allowed * @path: file * @mode: new mode * * Check for permission to change a mode of the file @path. The new mode is * specified in @mode which is a bitmask of constants from * . * * Return: Returns 0 if permission is granted. */ int security_path_chmod(const struct path *path, umode_t mode) { if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) return 0; return call_int_hook(path_chmod, path, mode); } /** * security_path_chown() - Check if changing the file's owner/group is allowed * @path: file * @uid: file owner * @gid: file group * * Check for permission to change owner/group of a file or directory. * * Return: Returns 0 if permission is granted. */ int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) { if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) return 0; return call_int_hook(path_chown, path, uid, gid); } /** * security_path_chroot() - Check if changing the root directory is allowed * @path: directory * * Check for permission to change root directory. * * Return: Returns 0 if permission is granted. */ int security_path_chroot(const struct path *path) { return call_int_hook(path_chroot, path); } #endif /* CONFIG_SECURITY_PATH */ /** * security_inode_create() - Check if creating a file is allowed * @dir: the parent directory * @dentry: the file being created * @mode: requested file mode * * Check permission to create a regular file. * * Return: Returns 0 if permission is granted. */ int security_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) { if (unlikely(IS_PRIVATE(dir))) return 0; return call_int_hook(inode_create, dir, dentry, mode); } EXPORT_SYMBOL_GPL(security_inode_create); /** * security_inode_post_create_tmpfile() - Update inode security of new tmpfile * @idmap: idmap of the mount * @inode: inode of the new tmpfile * * Update inode security data after a tmpfile has been created. */ void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, struct inode *inode) { if (unlikely(IS_PRIVATE(inode))) return; call_void_hook(inode_post_create_tmpfile, idmap, inode); } /** * security_inode_link() - Check if creating a hard link is allowed * @old_dentry: existing file * @dir: new parent directory * @new_dentry: new link * * Check permission before creating a new hard link to a file. * * Return: Returns 0 if permission is granted. */ int security_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) return 0; return call_int_hook(inode_link, old_dentry, dir, new_dentry); } /** * security_inode_unlink() - Check if removing a hard link is allowed * @dir: parent directory * @dentry: file * * Check the permission to remove a hard link to a file. * * Return: Returns 0 if permission is granted. */ int security_inode_unlink(struct inode *dir, struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_unlink, dir, dentry); } /** * security_inode_symlink() - Check if creating a symbolic link is allowed * @dir: parent directory * @dentry: symbolic link * @old_name: existing filename * * Check the permission to create a symbolic link to a file. * * Return: Returns 0 if permission is granted. */ int security_inode_symlink(struct inode *dir, struct dentry *dentry, const char *old_name) { if (unlikely(IS_PRIVATE(dir))) return 0; return call_int_hook(inode_symlink, dir, dentry, old_name); } /** * security_inode_mkdir() - Check if creation a new director is allowed * @dir: parent directory * @dentry: new directory * @mode: new directory mode * * Check permissions to create a new directory in the existing directory * associated with inode structure @dir. * * Return: Returns 0 if permission is granted. */ int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { if (unlikely(IS_PRIVATE(dir))) return 0; return call_int_hook(inode_mkdir, dir, dentry, mode); } EXPORT_SYMBOL_GPL(security_inode_mkdir); /** * security_inode_rmdir() - Check if removing a directory is allowed * @dir: parent directory * @dentry: directory to be removed * * Check the permission to remove a directory. * * Return: Returns 0 if permission is granted. */ int security_inode_rmdir(struct inode *dir, struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_rmdir, dir, dentry); } /** * security_inode_mknod() - Check if creating a special file is allowed * @dir: parent directory * @dentry: new file * @mode: new file mode * @dev: device number * * Check permissions when creating a special file (or a socket or a fifo file * created via the mknod system call). Note that if mknod operation is being * done for a regular file, then the create hook will be called and not this * hook. * * Return: Returns 0 if permission is granted. */ int security_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) { if (unlikely(IS_PRIVATE(dir))) return 0; return call_int_hook(inode_mknod, dir, dentry, mode, dev); } /** * security_inode_rename() - Check if renaming a file is allowed * @old_dir: parent directory of the old file * @old_dentry: the old file * @new_dir: parent directory of the new file * @new_dentry: the new file * @flags: flags * * Check for permission to rename a file or directory. * * Return: Returns 0 if permission is granted. */ int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || (d_is_positive(new_dentry) && IS_PRIVATE(d_backing_inode(new_dentry))))) return 0; if (flags & RENAME_EXCHANGE) { int err = call_int_hook(inode_rename, new_dir, new_dentry, old_dir, old_dentry); if (err) return err; } return call_int_hook(inode_rename, old_dir, old_dentry, new_dir, new_dentry); } /** * security_inode_readlink() - Check if reading a symbolic link is allowed * @dentry: link * * Check the permission to read the symbolic link. * * Return: Returns 0 if permission is granted. */ int security_inode_readlink(struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_readlink, dentry); } /** * security_inode_follow_link() - Check if following a symbolic link is allowed * @dentry: link dentry * @inode: link inode * @rcu: true if in RCU-walk mode * * Check permission to follow a symbolic link when looking up a pathname. If * @rcu is true, @inode is not stable. * * Return: Returns 0 if permission is granted. */ int security_inode_follow_link(struct dentry *dentry, struct inode *inode, bool rcu) { if (unlikely(IS_PRIVATE(inode))) return 0; return call_int_hook(inode_follow_link, dentry, inode, rcu); } /** * security_inode_permission() - Check if accessing an inode is allowed * @inode: inode * @mask: access mask * * Check permission before accessing an inode. This hook is called by the * existing Linux permission function, so a security module can use it to * provide additional checking for existing Linux permission checks. Notice * that this hook is called when a file is opened (as well as many other * operations), whereas the file_security_ops permission hook is called when * the actual read/write operations are performed. * * Return: Returns 0 if permission is granted. */ int security_inode_permission(struct inode *inode, int mask) { if (unlikely(IS_PRIVATE(inode))) return 0; return call_int_hook(inode_permission, inode, mask); } /** * security_inode_setattr() - Check if setting file attributes is allowed * @idmap: idmap of the mount * @dentry: file * @attr: new attributes * * Check permission before setting file attributes. Note that the kernel call * to notify_change is performed from several locations, whenever file * attributes change (such as when a file is truncated, chown/chmod operations, * transferring disk quotas, etc). * * Return: Returns 0 if permission is granted. */ int security_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_setattr, idmap, dentry, attr); } EXPORT_SYMBOL_GPL(security_inode_setattr); /** * security_inode_post_setattr() - Update the inode after a setattr operation * @idmap: idmap of the mount * @dentry: file * @ia_valid: file attributes set * * Update inode security field after successful setting file attributes. */ void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, int ia_valid) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return; call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); } /** * security_inode_getattr() - Check if getting file attributes is allowed * @path: file * * Check permission before obtaining file attributes. * * Return: Returns 0 if permission is granted. */ int security_inode_getattr(const struct path *path) { if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) return 0; return call_int_hook(inode_getattr, path); } /** * security_inode_setxattr() - Check if setting file xattrs is allowed * @idmap: idmap of the mount * @dentry: file * @name: xattr name * @value: xattr value * @size: size of xattr value * @flags: flags * * This hook performs the desired permission checks before setting the extended * attributes (xattrs) on @dentry. It is important to note that we have some * additional logic before the main LSM implementation calls to detect if we * need to perform an additional capability check at the LSM layer. * * Normally we enforce a capability check prior to executing the various LSM * hook implementations, but if a LSM wants to avoid this capability check, * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for * xattrs that it wants to avoid the capability check, leaving the LSM fully * responsible for enforcing the access control for the specific xattr. If all * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, * or return a 0 (the default return value), the capability check is still * performed. If no 'inode_xattr_skipcap' hooks are registered the capability * check is performed. * * Return: Returns 0 if permission is granted. */ int security_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { int rc; if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; /* enforce the capability checks at the lsm layer, if needed */ if (!call_int_hook(inode_xattr_skipcap, name)) { rc = cap_inode_setxattr(dentry, name, value, size, flags); if (rc) return rc; } return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, flags); } /** * security_inode_set_acl() - Check if setting posix acls is allowed * @idmap: idmap of the mount * @dentry: file * @acl_name: acl name * @kacl: acl struct * * Check permission before setting posix acls, the posix acls in @kacl are * identified by @acl_name. * * Return: Returns 0 if permission is granted. */ int security_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); } /** * security_inode_post_set_acl() - Update inode security from posix acls set * @dentry: file * @acl_name: acl name * @kacl: acl struct * * Update inode security data after successfully setting posix acls on @dentry. * The posix acls in @kacl are identified by @acl_name. */ void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return; call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); } /** * security_inode_get_acl() - Check if reading posix acls is allowed * @idmap: idmap of the mount * @dentry: file * @acl_name: acl name * * Check permission before getting osix acls, the posix acls are identified by * @acl_name. * * Return: Returns 0 if permission is granted. */ int security_inode_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_get_acl, idmap, dentry, acl_name); } /** * security_inode_remove_acl() - Check if removing a posix acl is allowed * @idmap: idmap of the mount * @dentry: file * @acl_name: acl name * * Check permission before removing posix acls, the posix acls are identified * by @acl_name. * * Return: Returns 0 if permission is granted. */ int security_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); } /** * security_inode_post_remove_acl() - Update inode security after rm posix acls * @idmap: idmap of the mount * @dentry: file * @acl_name: acl name * * Update inode security data after successfully removing posix acls on * @dentry in @idmap. The posix acls are identified by @acl_name. */ void security_inode_post_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return; call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); } /** * security_inode_post_setxattr() - Update the inode after a setxattr operation * @dentry: file * @name: xattr name * @value: xattr value * @size: xattr value size * @flags: flags * * Update inode security field after successful setxattr operation. */ void security_inode_post_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return; call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); } /** * security_inode_getxattr() - Check if xattr access is allowed * @dentry: file * @name: xattr name * * Check permission before obtaining the extended attributes identified by * @name for @dentry. * * Return: Returns 0 if permission is granted. */ int security_inode_getxattr(struct dentry *dentry, const char *name) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_getxattr, dentry, name); } /** * security_inode_listxattr() - Check if listing xattrs is allowed * @dentry: file * * Check permission before obtaining the list of extended attribute names for * @dentry. * * Return: Returns 0 if permission is granted. */ int security_inode_listxattr(struct dentry *dentry) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; return call_int_hook(inode_listxattr, dentry); } /** * security_inode_removexattr() - Check if removing an xattr is allowed * @idmap: idmap of the mount * @dentry: file * @name: xattr name * * This hook performs the desired permission checks before setting the extended * attributes (xattrs) on @dentry. It is important to note that we have some * additional logic before the main LSM implementation calls to detect if we * need to perform an additional capability check at the LSM layer. * * Normally we enforce a capability check prior to executing the various LSM * hook implementations, but if a LSM wants to avoid this capability check, * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for * xattrs that it wants to avoid the capability check, leaving the LSM fully * responsible for enforcing the access control for the specific xattr. If all * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, * or return a 0 (the default return value), the capability check is still * performed. If no 'inode_xattr_skipcap' hooks are registered the capability * check is performed. * * Return: Returns 0 if permission is granted. */ int security_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name) { int rc; if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return 0; /* enforce the capability checks at the lsm layer, if needed */ if (!call_int_hook(inode_xattr_skipcap, name)) { rc = cap_inode_removexattr(idmap, dentry, name); if (rc) return rc; } return call_int_hook(inode_removexattr, idmap, dentry, name); } /** * security_inode_post_removexattr() - Update the inode after a removexattr op * @dentry: file * @name: xattr name * * Update the inode after a successful removexattr operation. */ void security_inode_post_removexattr(struct dentry *dentry, const char *name) { if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) return; call_void_hook(inode_post_removexattr, dentry, name); } /** * security_inode_need_killpriv() - Check if security_inode_killpriv() required * @dentry: associated dentry * * Called when an inode has been changed to determine if * security_inode_killpriv() should be called. * * Return: Return <0 on error to abort the inode change operation, return 0 if * security_inode_killpriv() does not need to be called, return >0 if * security_inode_killpriv() does need to be called. */ int security_inode_need_killpriv(struct dentry *dentry) { return call_int_hook(inode_need_killpriv, dentry); } /** * security_inode_killpriv() - The setuid bit is removed, update LSM state * @idmap: idmap of the mount * @dentry: associated dentry * * The @dentry's setuid bit is being removed. Remove similar security labels. * Called with the dentry->d_inode->i_mutex held. * * Return: Return 0 on success. If error is returned, then the operation * causing setuid bit removal is failed. */ int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry) { return call_int_hook(inode_killpriv, idmap, dentry); } /** * security_inode_getsecurity() - Get the xattr security label of an inode * @idmap: idmap of the mount * @inode: inode * @name: xattr name * @buffer: security label buffer * @alloc: allocation flag * * Retrieve a copy of the extended attribute representation of the security * label associated with @name for @inode via @buffer. Note that @name is the * remainder of the attribute name after the security prefix has been removed. * @alloc is used to specify if the call should return a value via the buffer * or just the value length. * * Return: Returns size of buffer on success. */ int security_inode_getsecurity(struct mnt_idmap *idmap, struct inode *inode, const char *name, void **buffer, bool alloc) { if (unlikely(IS_PRIVATE(inode))) return LSM_RET_DEFAULT(inode_getsecurity); return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, alloc); } /** * security_inode_setsecurity() - Set the xattr security label of an inode * @inode: inode * @name: xattr name * @value: security label * @size: length of security label * @flags: flags * * Set the security label associated with @name for @inode from the extended * attribute value @value. @size indicates the size of the @value in bytes. * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the * remainder of the attribute name after the security. prefix has been removed. * * Return: Returns 0 on success. */ int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags) { if (unlikely(IS_PRIVATE(inode))) return LSM_RET_DEFAULT(inode_setsecurity); return call_int_hook(inode_setsecurity, inode, name, value, size, flags); } /** * security_inode_listsecurity() - List the xattr security label names * @inode: inode * @buffer: buffer * @buffer_size: size of buffer * * Copy the extended attribute names for the security labels associated with * @inode into @buffer. The maximum size of @buffer is specified by * @buffer_size. @buffer may be NULL to request the size of the buffer * required. * * Return: Returns number of bytes used/required on success. */ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) { if (unlikely(IS_PRIVATE(inode))) return 0; return call_int_hook(inode_listsecurity, inode, buffer, buffer_size); } EXPORT_SYMBOL(security_inode_listsecurity); /** * security_inode_getsecid() - Get an inode's secid * @inode: inode * @secid: secid to return * * Get the secid associated with the node. In case of failure, @secid will be * set to zero. */ void security_inode_getsecid(struct inode *inode, u32 *secid) { call_void_hook(inode_getsecid, inode, secid); } /** * security_inode_copy_up() - Create new creds for an overlayfs copy-up op * @src: union dentry of copy-up file * @new: newly created creds * * A file is about to be copied up from lower layer to upper layer of overlay * filesystem. Security module can prepare a set of new creds and modify as * need be and return new creds. Caller will switch to new creds temporarily to * create new file and release newly allocated creds. * * Return: Returns 0 on success or a negative error code on error. */ int security_inode_copy_up(struct dentry *src, struct cred **new) { return call_int_hook(inode_copy_up, src, new); } EXPORT_SYMBOL(security_inode_copy_up); /** * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op * @src: union dentry of copy-up file * @name: xattr name * * Filter the xattrs being copied up when a unioned file is copied up from a * lower layer to the union/overlay layer. The caller is responsible for * reading and writing the xattrs, this hook is merely a filter. * * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr, * -EOPNOTSUPP if the security module does not know about attribute, * or a negative error code to abort the copy up. */ int security_inode_copy_up_xattr(struct dentry *src, const char *name) { int rc; rc = call_int_hook(inode_copy_up_xattr, src, name); if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr)) return rc; return LSM_RET_DEFAULT(inode_copy_up_xattr); } EXPORT_SYMBOL(security_inode_copy_up_xattr); /** * security_inode_setintegrity() - Set the inode's integrity data * @inode: inode * @type: type of integrity, e.g. hash digest, signature, etc * @value: the integrity value * @size: size of the integrity value * * Register a verified integrity measurement of a inode with LSMs. * LSMs should free the previously saved data if @value is NULL. * * Return: Returns 0 on success, negative values on failure. */ int security_inode_setintegrity(const struct inode *inode, enum lsm_integrity_type type, const void *value, size_t size) { return call_int_hook(inode_setintegrity, inode, type, value, size); } EXPORT_SYMBOL(security_inode_setintegrity); /** * security_kernfs_init_security() - Init LSM context for a kernfs node * @kn_dir: parent kernfs node * @kn: the kernfs node to initialize * * Initialize the security context of a newly created kernfs node based on its * own and its parent's attributes. * * Return: Returns 0 if permission is granted. */ int security_kernfs_init_security(struct kernfs_node *kn_dir, struct kernfs_node *kn) { return call_int_hook(kernfs_init_security, kn_dir, kn); } /** * security_file_permission() - Check file permissions * @file: file * @mask: requested permissions * * Check file permissions before accessing an open file. This hook is called * by various operations that read or write files. A security module can use * this hook to perform additional checking on these operations, e.g. to * revalidate permissions on use to support privilege bracketing or policy * changes. Notice that this hook is used when the actual read/write * operations are performed, whereas the inode_security_ops hook is called when * a file is opened (as well as many other operations). Although this hook can * be used to revalidate permissions for various system call operations that * read or write files, it does not address the revalidation of permissions for * memory-mapped files. Security modules must handle this separately if they * need such revalidation. * * Return: Returns 0 if permission is granted. */ int security_file_permission(struct file *file, int mask) { return call_int_hook(file_permission, file, mask); } /** * security_file_alloc() - Allocate and init a file's LSM blob * @file: the file * * Allocate and attach a security structure to the file->f_security field. The * security field is initialized to NULL when the structure is first created. * * Return: Return 0 if the hook is successful and permission is granted. */ int security_file_alloc(struct file *file) { int rc = lsm_file_alloc(file); if (rc) return rc; rc = call_int_hook(file_alloc_security, file); if (unlikely(rc)) security_file_free(file); return rc; } /** * security_file_release() - Perform actions before releasing the file ref * @file: the file * * Perform actions before releasing the last reference to a file. */ void security_file_release(struct file *file) { call_void_hook(file_release, file); } /** * security_file_free() - Free a file's LSM blob * @file: the file * * Deallocate and free any security structures stored in file->f_security. */ void security_file_free(struct file *file) { void *blob; call_void_hook(file_free_security, file); blob = file->f_security; if (blob) { file->f_security = NULL; kmem_cache_free(lsm_file_cache, blob); } } /** * security_file_ioctl() - Check if an ioctl is allowed * @file: associated file * @cmd: ioctl cmd * @arg: ioctl arguments * * Check permission for an ioctl operation on @file. Note that @arg sometimes * represents a user space pointer; in other cases, it may be a simple integer * value. When @arg represents a user space pointer, it should never be used * by the security module. * * Return: Returns 0 if permission is granted. */ int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { return call_int_hook(file_ioctl, file, cmd, arg); } EXPORT_SYMBOL_GPL(security_file_ioctl); /** * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode * @file: associated file * @cmd: ioctl cmd * @arg: ioctl arguments * * Compat version of security_file_ioctl() that correctly handles 32-bit * processes running on 64-bit kernels. * * Return: Returns 0 if permission is granted. */ int security_file_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg) { return call_int_hook(file_ioctl_compat, file, cmd, arg); } EXPORT_SYMBOL_GPL(security_file_ioctl_compat); static inline unsigned long mmap_prot(struct file *file, unsigned long prot) { /* * Does we have PROT_READ and does the application expect * it to imply PROT_EXEC? If not, nothing to talk about... */ if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ) return prot; if (!(current->personality & READ_IMPLIES_EXEC)) return prot; /* * if that's an anonymous mapping, let it. */ if (!file) return prot | PROT_EXEC; /* * ditto if it's not on noexec mount, except that on !MMU we need * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case */ if (!path_noexec(&file->f_path)) { #ifndef CONFIG_MMU if (file->f_op->mmap_capabilities) { unsigned caps = file->f_op->mmap_capabilities(file); if (!(caps & NOMMU_MAP_EXEC)) return prot; } #endif return prot | PROT_EXEC; } /* anything on noexec mount won't get PROT_EXEC */ return prot; } /** * security_mmap_file() - Check if mmap'ing a file is allowed * @file: file * @prot: protection applied by the kernel * @flags: flags * * Check permissions for a mmap operation. The @file may be NULL, e.g. if * mapping anonymous memory. * * Return: Returns 0 if permission is granted. */ int security_mmap_file(struct file *file, unsigned long prot, unsigned long flags) { return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot), flags); } /** * security_mmap_addr() - Check if mmap'ing an address is allowed * @addr: address * * Check permissions for a mmap operation at @addr. * * Return: Returns 0 if permission is granted. */ int security_mmap_addr(unsigned long addr) { return call_int_hook(mmap_addr, addr); } /** * security_file_mprotect() - Check if changing memory protections is allowed * @vma: memory region * @reqprot: application requested protection * @prot: protection applied by the kernel * * Check permissions before changing memory access permissions. * * Return: Returns 0 if permission is granted. */ int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, unsigned long prot) { return call_int_hook(file_mprotect, vma, reqprot, prot); } /** * security_file_lock() - Check if a file lock is allowed * @file: file * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK) * * Check permission before performing file locking operations. Note the hook * mediates both flock and fcntl style locks. * * Return: Returns 0 if permission is granted. */ int security_file_lock(struct file *file, unsigned int cmd) { return call_int_hook(file_lock, file, cmd); } /** * security_file_fcntl() - Check if fcntl() op is allowed * @file: file * @cmd: fcntl command * @arg: command argument * * Check permission before allowing the file operation specified by @cmd from * being performed on the file @file. Note that @arg sometimes represents a * user space pointer; in other cases, it may be a simple integer value. When * @arg represents a user space pointer, it should never be used by the * security module. * * Return: Returns 0 if permission is granted. */ int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) { return call_int_hook(file_fcntl, file, cmd, arg); } /** * security_file_set_fowner() - Set the file owner info in the LSM blob * @file: the file * * Save owner security information (typically from current->security) in * file->f_security for later use by the send_sigiotask hook. * * This hook is called with file->f_owner.lock held. * * Return: Returns 0 on success. */ void security_file_set_fowner(struct file *file) { call_void_hook(file_set_fowner, file); } /** * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed * @tsk: target task * @fown: signal sender * @sig: signal to be sent, SIGIO is sent if 0 * * Check permission for the file owner @fown to send SIGIO or SIGURG to the * process @tsk. Note that this hook is sometimes called from interrupt. Note * that the fown_struct, @fown, is never outside the context of a struct file, * so the file structure (and associated security information) can always be * obtained: container_of(fown, struct file, f_owner). * * Return: Returns 0 if permission is granted. */ int security_file_send_sigiotask(struct task_struct *tsk, struct fown_struct *fown, int sig) { return call_int_hook(file_send_sigiotask, tsk, fown, sig); } /** * security_file_receive() - Check if receiving a file via IPC is allowed * @file: file being received * * This hook allows security modules to control the ability of a process to * receive an open file descriptor via socket IPC. * * Return: Returns 0 if permission is granted. */ int security_file_receive(struct file *file) { return call_int_hook(file_receive, file); } /** * security_file_open() - Save open() time state for late use by the LSM * @file: * * Save open-time permission checking state for later use upon file_permission, * and recheck access if anything has changed since inode_permission. * * Return: Returns 0 if permission is granted. */ int security_file_open(struct file *file) { int ret; ret = call_int_hook(file_open, file); if (ret) return ret; return fsnotify_open_perm(file); } /** * security_file_post_open() - Evaluate a file after it has been opened * @file: the file * @mask: access mask * * Evaluate an opened file and the access mask requested with open(). The hook * is useful for LSMs that require the file content to be available in order to * make decisions. * * Return: Returns 0 if permission is granted. */ int security_file_post_open(struct file *file, int mask) { return call_int_hook(file_post_open, file, mask); } EXPORT_SYMBOL_GPL(security_file_post_open); /** * security_file_truncate() - Check if truncating a file is allowed * @file: file * * Check permission before truncating a file, i.e. using ftruncate. Note that * truncation permission may also be checked based on the path, using the * @path_truncate hook. * * Return: Returns 0 if permission is granted. */ int security_file_truncate(struct file *file) { return call_int_hook(file_truncate, file); } /** * security_task_alloc() - Allocate a task's LSM blob * @task: the task * @clone_flags: flags indicating what is being shared * * Handle allocation of task-related resources. * * Return: Returns a zero on success, negative values on failure. */ int security_task_alloc(struct task_struct *task, unsigned long clone_flags) { int rc = lsm_task_alloc(task); if (rc) return rc; rc = call_int_hook(task_alloc, task, clone_flags); if (unlikely(rc)) security_task_free(task); return rc; } /** * security_task_free() - Free a task's LSM blob and related resources * @task: task * * Handle release of task-related resources. Note that this can be called from * interrupt context. */ void security_task_free(struct task_struct *task) { call_void_hook(task_free, task); kfree(task->security); task->security = NULL; } /** * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer * @cred: credentials * @gfp: gfp flags * * Only allocate sufficient memory and attach to @cred such that * cred_transfer() will not get ENOMEM. * * Return: Returns 0 on success, negative values on failure. */ int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) { int rc = lsm_cred_alloc(cred, gfp); if (rc) return rc; rc = call_int_hook(cred_alloc_blank, cred, gfp); if (unlikely(rc)) security_cred_free(cred); return rc; } /** * security_cred_free() - Free the cred's LSM blob and associated resources * @cred: credentials * * Deallocate and clear the cred->security field in a set of credentials. */ void security_cred_free(struct cred *cred) { /* * There is a failure case in prepare_creds() that * may result in a call here with ->security being NULL. */ if (unlikely(cred->security == NULL)) return; call_void_hook(cred_free, cred); kfree(cred->security); cred->security = NULL; } /** * security_prepare_creds() - Prepare a new set of credentials * @new: new credentials * @old: original credentials * @gfp: gfp flags * * Prepare a new set of credentials by copying the data from the old set. * * Return: Returns 0 on success, negative values on failure. */ int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) { int rc = lsm_cred_alloc(new, gfp); if (rc) return rc; rc = call_int_hook(cred_prepare, new, old, gfp); if (unlikely(rc)) security_cred_free(new); return rc; } /** * security_transfer_creds() - Transfer creds * @new: target credentials * @old: original credentials * * Transfer data from original creds to new creds. */ void security_transfer_creds(struct cred *new, const struct cred *old) { call_void_hook(cred_transfer, new, old); } /** * security_cred_getsecid() - Get the secid from a set of credentials * @c: credentials * @secid: secid value * * Retrieve the security identifier of the cred structure @c. In case of * failure, @secid will be set to zero. */ void security_cred_getsecid(const struct cred *c, u32 *secid) { *secid = 0; call_void_hook(cred_getsecid, c, secid); } EXPORT_SYMBOL(security_cred_getsecid); /** * security_kernel_act_as() - Set the kernel credentials to act as secid * @new: credentials * @secid: secid * * Set the credentials for a kernel service to act as (subjective context). * The current task must be the one that nominated @secid. * * Return: Returns 0 if successful. */ int security_kernel_act_as(struct cred *new, u32 secid) { return call_int_hook(kernel_act_as, new, secid); } /** * security_kernel_create_files_as() - Set file creation context using an inode * @new: target credentials * @inode: reference inode * * Set the file creation context in a set of credentials to be the same as the * objective context of the specified inode. The current task must be the one * that nominated @inode. * * Return: Returns 0 if successful. */ int security_kernel_create_files_as(struct cred *new, struct inode *inode) { return call_int_hook(kernel_create_files_as, new, inode); } /** * security_kernel_module_request() - Check if loading a module is allowed * @kmod_name: module name * * Ability to trigger the kernel to automatically upcall to userspace for * userspace to load a kernel module with the given name. * * Return: Returns 0 if successful. */ int security_kernel_module_request(char *kmod_name) { return call_int_hook(kernel_module_request, kmod_name); } /** * security_kernel_read_file() - Read a file specified by userspace * @file: file * @id: file identifier * @contents: trust if security_kernel_post_read_file() will be called * * Read a file specified by userspace. * * Return: Returns 0 if permission is granted. */ int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, bool contents) { return call_int_hook(kernel_read_file, file, id, contents); } EXPORT_SYMBOL_GPL(security_kernel_read_file); /** * security_kernel_post_read_file() - Read a file specified by userspace * @file: file * @buf: file contents * @size: size of file contents * @id: file identifier * * Read a file specified by userspace. This must be paired with a prior call * to security_kernel_read_file() call that indicated this hook would also be * called, see security_kernel_read_file() for more information. * * Return: Returns 0 if permission is granted. */ int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, enum kernel_read_file_id id) { return call_int_hook(kernel_post_read_file, file, buf, size, id); } EXPORT_SYMBOL_GPL(security_kernel_post_read_file); /** * security_kernel_load_data() - Load data provided by userspace * @id: data identifier * @contents: true if security_kernel_post_load_data() will be called * * Load data provided by userspace. * * Return: Returns 0 if permission is granted. */ int security_kernel_load_data(enum kernel_load_data_id id, bool contents) { return call_int_hook(kernel_load_data, id, contents); } EXPORT_SYMBOL_GPL(security_kernel_load_data); /** * security_kernel_post_load_data() - Load userspace data from a non-file source * @buf: data * @size: size of data * @id: data identifier * @description: text description of data, specific to the id value * * Load data provided by a non-file source (usually userspace buffer). This * must be paired with a prior security_kernel_load_data() call that indicated * this hook would also be called, see security_kernel_load_data() for more * information. * * Return: Returns 0 if permission is granted. */ int security_kernel_post_load_data(char *buf, loff_t size, enum kernel_load_data_id id, char *description) { return call_int_hook(kernel_post_load_data, buf, size, id, description); } EXPORT_SYMBOL_GPL(security_kernel_post_load_data); /** * security_task_fix_setuid() - Update LSM with new user id attributes * @new: updated credentials * @old: credentials being replaced * @flags: LSM_SETID_* flag values * * Update the module's state after setting one or more of the user identity * attributes of the current process. The @flags parameter indicates which of * the set*uid system calls invoked this hook. If @new is the set of * credentials that will be installed. Modifications should be made to this * rather than to @current->cred. * * Return: Returns 0 on success. */ int security_task_fix_setuid(struct cred *new, const struct cred *old, int flags) { return call_int_hook(task_fix_setuid, new, old, flags); } /** * security_task_fix_setgid() - Update LSM with new group id attributes * @new: updated credentials * @old: credentials being replaced * @flags: LSM_SETID_* flag value * * Update the module's state after setting one or more of the group identity * attributes of the current process. The @flags parameter indicates which of * the set*gid system calls invoked this hook. @new is the set of credentials * that will be installed. Modifications should be made to this rather than to * @current->cred. * * Return: Returns 0 on success. */ int security_task_fix_setgid(struct cred *new, const struct cred *old, int flags) { return call_int_hook(task_fix_setgid, new, old, flags); } /** * security_task_fix_setgroups() - Update LSM with new supplementary groups * @new: updated credentials * @old: credentials being replaced * * Update the module's state after setting the supplementary group identity * attributes of the current process. @new is the set of credentials that will * be installed. Modifications should be made to this rather than to * @current->cred. * * Return: Returns 0 on success. */ int security_task_fix_setgroups(struct cred *new, const struct cred *old) { return call_int_hook(task_fix_setgroups, new, old); } /** * security_task_setpgid() - Check if setting the pgid is allowed * @p: task being modified * @pgid: new pgid * * Check permission before setting the process group identifier of the process * @p to @pgid. * * Return: Returns 0 if permission is granted. */ int security_task_setpgid(struct task_struct *p, pid_t pgid) { return call_int_hook(task_setpgid, p, pgid); } /** * security_task_getpgid() - Check if getting the pgid is allowed * @p: task * * Check permission before getting the process group identifier of the process * @p. * * Return: Returns 0 if permission is granted. */ int security_task_getpgid(struct task_struct *p) { return call_int_hook(task_getpgid, p); } /** * security_task_getsid() - Check if getting the session id is allowed * @p: task * * Check permission before getting the session identifier of the process @p. * * Return: Returns 0 if permission is granted. */ int security_task_getsid(struct task_struct *p) { return call_int_hook(task_getsid, p); } /** * security_current_getsecid_subj() - Get the current task's subjective secid * @secid: secid value * * Retrieve the subjective security identifier of the current task and return * it in @secid. In case of failure, @secid will be set to zero. */ void security_current_getsecid_subj(u32 *secid) { *secid = 0; call_void_hook(current_getsecid_subj, secid); } EXPORT_SYMBOL(security_current_getsecid_subj); /** * security_task_getsecid_obj() - Get a task's objective secid * @p: target task * @secid: secid value * * Retrieve the objective security identifier of the task_struct in @p and * return it in @secid. In case of failure, @secid will be set to zero. */ void security_task_getsecid_obj(struct task_struct *p, u32 *secid) { *secid = 0; call_void_hook(task_getsecid_obj, p, secid); } EXPORT_SYMBOL(security_task_getsecid_obj); /** * security_task_setnice() - Check if setting a task's nice value is allowed * @p: target task * @nice: nice value * * Check permission before setting the nice value of @p to @nice. * * Return: Returns 0 if permission is granted. */ int security_task_setnice(struct task_struct *p, int nice) { return call_int_hook(task_setnice, p, nice); } /** * security_task_setioprio() - Check if setting a task's ioprio is allowed * @p: target task * @ioprio: ioprio value * * Check permission before setting the ioprio value of @p to @ioprio. * * Return: Returns 0 if permission is granted. */ int security_task_setioprio(struct task_struct *p, int ioprio) { return call_int_hook(task_setioprio, p, ioprio); } /** * security_task_getioprio() - Check if getting a task's ioprio is allowed * @p: task * * Check permission before getting the ioprio value of @p. * * Return: Returns 0 if permission is granted. */ int security_task_getioprio(struct task_struct *p) { return call_int_hook(task_getioprio, p); } /** * security_task_prlimit() - Check if get/setting resources limits is allowed * @cred: current task credentials * @tcred: target task credentials * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both * * Check permission before getting and/or setting the resource limits of * another task. * * Return: Returns 0 if permission is granted. */ int security_task_prlimit(const struct cred *cred, const struct cred *tcred, unsigned int flags) { return call_int_hook(task_prlimit, cred, tcred, flags); } /** * security_task_setrlimit() - Check if setting a new rlimit value is allowed * @p: target task's group leader * @resource: resource whose limit is being set * @new_rlim: new resource limit * * Check permission before setting the resource limits of process @p for * @resource to @new_rlim. The old resource limit values can be examined by * dereferencing (p->signal->rlim + resource). * * Return: Returns 0 if permission is granted. */ int security_task_setrlimit(struct task_struct *p, unsigned int resource, struct rlimit *new_rlim) { return call_int_hook(task_setrlimit, p, resource, new_rlim); } /** * security_task_setscheduler() - Check if setting sched policy/param is allowed * @p: target task * * Check permission before setting scheduling policy and/or parameters of * process @p. * * Return: Returns 0 if permission is granted. */ int security_task_setscheduler(struct task_struct *p) { return call_int_hook(task_setscheduler, p); } /** * security_task_getscheduler() - Check if getting scheduling info is allowed * @p: target task * * Check permission before obtaining scheduling information for process @p. * * Return: Returns 0 if permission is granted. */ int security_task_getscheduler(struct task_struct *p) { return call_int_hook(task_getscheduler, p); } /** * security_task_movememory() - Check if moving memory is allowed * @p: task * * Check permission before moving memory owned by process @p. * * Return: Returns 0 if permission is granted. */ int security_task_movememory(struct task_struct *p) { return call_int_hook(task_movememory, p); } /** * security_task_kill() - Check if sending a signal is allowed * @p: target process * @info: signal information * @sig: signal value * @cred: credentials of the signal sender, NULL if @current * * Check permission before sending signal @sig to @p. @info can be NULL, the * constant 1, or a pointer to a kernel_siginfo structure. If @info is 1 or * SI_FROMKERNEL(info) is true, then the signal should be viewed as coming from * the kernel and should typically be permitted. SIGIO signals are handled * separately by the send_sigiotask hook in file_security_ops. * * Return: Returns 0 if permission is granted. */ int security_task_kill(struct task_struct *p, struct kernel_siginfo *info, int sig, const struct cred *cred) { return call_int_hook(task_kill, p, info, sig, cred); } /** * security_task_prctl() - Check if a prctl op is allowed * @option: operation * @arg2: argument * @arg3: argument * @arg4: argument * @arg5: argument * * Check permission before performing a process control operation on the * current process. * * Return: Return -ENOSYS if no-one wanted to handle this op, any other value * to cause prctl() to return immediately with that value. */ int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5) { int thisrc; int rc = LSM_RET_DEFAULT(task_prctl); struct lsm_static_call *scall; lsm_for_each_hook(scall, task_prctl) { thisrc = scall->hl->hook.task_prctl(option, arg2, arg3, arg4, arg5); if (thisrc != LSM_RET_DEFAULT(task_prctl)) { rc = thisrc; if (thisrc != 0) break; } } return rc; } /** * security_task_to_inode() - Set the security attributes of a task's inode * @p: task * @inode: inode * * Set the security attributes for an inode based on an associated task's * security attributes, e.g. for /proc/pid inodes. */ void security_task_to_inode(struct task_struct *p, struct inode *inode) { call_void_hook(task_to_inode, p, inode); } /** * security_create_user_ns() - Check if creating a new userns is allowed * @cred: prepared creds * * Check permission prior to creating a new user namespace. * * Return: Returns 0 if successful, otherwise < 0 error code. */ int security_create_user_ns(const struct cred *cred) { return call_int_hook(userns_create, cred); } /** * security_ipc_permission() - Check if sysv ipc access is allowed * @ipcp: ipc permission structure * @flag: requested permissions * * Check permissions for access to IPC. * * Return: Returns 0 if permission is granted. */ int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) { return call_int_hook(ipc_permission, ipcp, flag); } /** * security_ipc_getsecid() - Get the sysv ipc object's secid * @ipcp: ipc permission structure * @secid: secid pointer * * Get the secid associated with the ipc object. In case of failure, @secid * will be set to zero. */ void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) { *secid = 0; call_void_hook(ipc_getsecid, ipcp, secid); } /** * security_msg_msg_alloc() - Allocate a sysv ipc message LSM blob * @msg: message structure * * Allocate and attach a security structure to the msg->security field. The * security field is initialized to NULL when the structure is first created. * * Return: Return 0 if operation was successful and permission is granted. */ int security_msg_msg_alloc(struct msg_msg *msg) { int rc = lsm_msg_msg_alloc(msg); if (unlikely(rc)) return rc; rc = call_int_hook(msg_msg_alloc_security, msg); if (unlikely(rc)) security_msg_msg_free(msg); return rc; } /** * security_msg_msg_free() - Free a sysv ipc message LSM blob * @msg: message structure * * Deallocate the security structure for this message. */ void security_msg_msg_free(struct msg_msg *msg) { call_void_hook(msg_msg_free_security, msg); kfree(msg->security); msg->security = NULL; } /** * security_msg_queue_alloc() - Allocate a sysv ipc msg queue LSM blob * @msq: sysv ipc permission structure * * Allocate and attach a security structure to @msg. The security field is * initialized to NULL when the structure is first created. * * Return: Returns 0 if operation was successful and permission is granted. */ int security_msg_queue_alloc(struct kern_ipc_perm *msq) { int rc = lsm_ipc_alloc(msq); if (unlikely(rc)) return rc; rc = call_int_hook(msg_queue_alloc_security, msq); if (unlikely(rc)) security_msg_queue_free(msq); return rc; } /** * security_msg_queue_free() - Free a sysv ipc msg queue LSM blob * @msq: sysv ipc permission structure * * Deallocate security field @perm->security for the message queue. */ void security_msg_queue_free(struct kern_ipc_perm *msq) { call_void_hook(msg_queue_free_security, msq); kfree(msq->security); msq->security = NULL; } /** * security_msg_queue_associate() - Check if a msg queue operation is allowed * @msq: sysv ipc permission structure * @msqflg: operation flags * * Check permission when a message queue is requested through the msgget system * call. This hook is only called when returning the message queue identifier * for an existing message queue, not when a new message queue is created. * * Return: Return 0 if permission is granted. */ int security_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) { return call_int_hook(msg_queue_associate, msq, msqflg); } /** * security_msg_queue_msgctl() - Check if a msg queue operation is allowed * @msq: sysv ipc permission structure * @cmd: operation * * Check permission when a message control operation specified by @cmd is to be * performed on the message queue with permissions. * * Return: Returns 0 if permission is granted. */ int security_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) { return call_int_hook(msg_queue_msgctl, msq, cmd); } /** * security_msg_queue_msgsnd() - Check if sending a sysv ipc message is allowed * @msq: sysv ipc permission structure * @msg: message * @msqflg: operation flags * * Check permission before a message, @msg, is enqueued on the message queue * with permissions specified in @msq. * * Return: Returns 0 if permission is granted. */ int security_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) { return call_int_hook(msg_queue_msgsnd, msq, msg, msqflg); } /** * security_msg_queue_msgrcv() - Check if receiving a sysv ipc msg is allowed * @msq: sysv ipc permission structure * @msg: message * @target: target task * @type: type of message requested * @mode: operation flags * * Check permission before a message, @msg, is removed from the message queue. * The @target task structure contains a pointer to the process that will be * receiving the message (not equal to the current process when inline receives * are being performed). * * Return: Returns 0 if permission is granted. */ int security_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, struct task_struct *target, long type, int mode) { return call_int_hook(msg_queue_msgrcv, msq, msg, target, type, mode); } /** * security_shm_alloc() - Allocate a sysv shm LSM blob * @shp: sysv ipc permission structure * * Allocate and attach a security structure to the @shp security field. The * security field is initialized to NULL when the structure is first created. * * Return: Returns 0 if operation was successful and permission is granted. */ int security_shm_alloc(struct kern_ipc_perm *shp) { int rc = lsm_ipc_alloc(shp); if (unlikely(rc)) return rc; rc = call_int_hook(shm_alloc_security, shp); if (unlikely(rc)) security_shm_free(shp); return rc; } /** * security_shm_free() - Free a sysv shm LSM blob * @shp: sysv ipc permission structure * * Deallocate the security structure @perm->security for the memory segment. */ void security_shm_free(struct kern_ipc_perm *shp) { call_void_hook(shm_free_security, shp); kfree(shp->security); shp->security = NULL; } /** * security_shm_associate() - Check if a sysv shm operation is allowed * @shp: sysv ipc permission structure * @shmflg: operation flags * * Check permission when a shared memory region is requested through the shmget * system call. This hook is only called when returning the shared memory * region identifier for an existing region, not when a new shared memory * region is created. * * Return: Returns 0 if permission is granted. */ int security_shm_associate(struct kern_ipc_perm *shp, int shmflg) { return call_int_hook(shm_associate, shp, shmflg); } /** * security_shm_shmctl() - Check if a sysv shm operation is allowed * @shp: sysv ipc permission structure * @cmd: operation * * Check permission when a shared memory control operation specified by @cmd is * to be performed on the shared memory region with permissions in @shp. * * Return: Return 0 if permission is granted. */ int security_shm_shmctl(struct kern_ipc_perm *shp, int cmd) { return call_int_hook(shm_shmctl, shp, cmd); } /** * security_shm_shmat() - Check if a sysv shm attach operation is allowed * @shp: sysv ipc permission structure * @shmaddr: address of memory region to attach * @shmflg: operation flags * * Check permissions prior to allowing the shmat system call to attach the * shared memory segment with permissions @shp to the data segment of the * calling process. The attaching address is specified by @shmaddr. * * Return: Returns 0 if permission is granted. */ int security_shm_shmat(struct kern_ipc_perm *shp, char __user *shmaddr, int shmflg) { return call_int_hook(shm_shmat, shp, shmaddr, shmflg); } /** * security_sem_alloc() - Allocate a sysv semaphore LSM blob * @sma: sysv ipc permission structure * * Allocate and attach a security structure to the @sma security field. The * security field is initialized to NULL when the structure is first created. * * Return: Returns 0 if operation was successful and permission is granted. */ int security_sem_alloc(struct kern_ipc_perm *sma) { int rc = lsm_ipc_alloc(sma); if (unlikely(rc)) return rc; rc = call_int_hook(sem_alloc_security, sma); if (unlikely(rc)) security_sem_free(sma); return rc; } /** * security_sem_free() - Free a sysv semaphore LSM blob * @sma: sysv ipc permission structure * * Deallocate security structure @sma->security for the semaphore. */ void security_sem_free(struct kern_ipc_perm *sma) { call_void_hook(sem_free_security, sma); kfree(sma->security); sma->security = NULL; } /** * security_sem_associate() - Check if a sysv semaphore operation is allowed * @sma: sysv ipc permission structure * @semflg: operation flags * * Check permission when a semaphore is requested through the semget system * call. This hook is only called when returning the semaphore identifier for * an existing semaphore, not when a new one must be created. * * Return: Returns 0 if permission is granted. */ int security_sem_associate(struct kern_ipc_perm *sma, int semflg) { return call_int_hook(sem_associate, sma, semflg); } /** * security_sem_semctl() - Check if a sysv semaphore operation is allowed * @sma: sysv ipc permission structure * @cmd: operation * * Check permission when a semaphore operation specified by @cmd is to be * performed on the semaphore. * * Return: Returns 0 if permission is granted. */ int security_sem_semctl(struct kern_ipc_perm *sma, int cmd) { return call_int_hook(sem_semctl, sma, cmd); } /** * security_sem_semop() - Check if a sysv semaphore operation is allowed * @sma: sysv ipc permission structure * @sops: operations to perform * @nsops: number of operations * @alter: flag indicating changes will be made * * Check permissions before performing operations on members of the semaphore * set. If the @alter flag is nonzero, the semaphore set may be modified. * * Return: Returns 0 if permission is granted. */ int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, unsigned nsops, int alter) { return call_int_hook(sem_semop, sma, sops, nsops, alter); } /** * security_d_instantiate() - Populate an inode's LSM state based on a dentry * @dentry: dentry * @inode: inode * * Fill in @inode security information for a @dentry if allowed. */ void security_d_instantiate(struct dentry *dentry, struct inode *inode) { if (unlikely(inode && IS_PRIVATE(inode))) return; call_void_hook(d_instantiate, dentry, inode); } EXPORT_SYMBOL(security_d_instantiate); /* * Please keep this in sync with it's counterpart in security/lsm_syscalls.c */ /** * security_getselfattr - Read an LSM attribute of the current process. * @attr: which attribute to return * @uctx: the user-space destination for the information, or NULL * @size: pointer to the size of space available to receive the data * @flags: special handling options. LSM_FLAG_SINGLE indicates that only * attributes associated with the LSM identified in the passed @ctx be * reported. * * A NULL value for @uctx can be used to get both the number of attributes * and the size of the data. * * Returns the number of attributes found on success, negative value * on error. @size is reset to the total size of the data. * If @size is insufficient to contain the data -E2BIG is returned. */ int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx, u32 __user *size, u32 flags) { struct lsm_static_call *scall; struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, }; u8 __user *base = (u8 __user *)uctx; u32 entrysize; u32 total = 0; u32 left; bool toobig = false; bool single = false; int count = 0; int rc; if (attr == LSM_ATTR_UNDEF) return -EINVAL; if (size == NULL) return -EINVAL; if (get_user(left, size)) return -EFAULT; if (flags) { /* * Only flag supported is LSM_FLAG_SINGLE */ if (flags != LSM_FLAG_SINGLE || !uctx) return -EINVAL; if (copy_from_user(&lctx, uctx, sizeof(lctx))) return -EFAULT; /* * If the LSM ID isn't specified it is an error. */ if (lctx.id == LSM_ID_UNDEF) return -EINVAL; single = true; } /* * In the usual case gather all the data from the LSMs. * In the single case only get the data from the LSM specified. */ lsm_for_each_hook(scall, getselfattr) { if (single && lctx.id != scall->hl->lsmid->id) continue; entrysize = left; if (base) uctx = (struct lsm_ctx __user *)(base + total); rc = scall->hl->hook.getselfattr(attr, uctx, &entrysize, flags); if (rc == -EOPNOTSUPP) { rc = 0; continue; } if (rc == -E2BIG) { rc = 0; left = 0; toobig = true; } else if (rc < 0) return rc; else left -= entrysize; total += entrysize; count += rc; if (single) break; } if (put_user(total, size)) return -EFAULT; if (toobig) return -E2BIG; if (count == 0) return LSM_RET_DEFAULT(getselfattr); return count; } /* * Please keep this in sync with it's counterpart in security/lsm_syscalls.c */ /** * security_setselfattr - Set an LSM attribute on the current process. * @attr: which attribute to set * @uctx: the user-space source for the information * @size: the size of the data * @flags: reserved for future use, must be 0 * * Set an LSM attribute for the current process. The LSM, attribute * and new value are included in @uctx. * * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT * if the user buffer is inaccessible, E2BIG if size is too big, or an * LSM specific failure. */ int security_setselfattr(unsigned int attr, struct lsm_ctx __user *uctx, u32 size, u32 flags) { struct lsm_static_call *scall; struct lsm_ctx *lctx; int rc = LSM_RET_DEFAULT(setselfattr); u64 required_len; if (flags) return -EINVAL; if (size < sizeof(*lctx)) return -EINVAL; if (size > PAGE_SIZE) return -E2BIG; lctx = memdup_user(uctx, size); if (IS_ERR(lctx)) return PTR_ERR(lctx); if (size < lctx->len || check_add_overflow(sizeof(*lctx), lctx->ctx_len, &required_len) || lctx->len < required_len) { rc = -EINVAL; goto free_out; } lsm_for_each_hook(scall, setselfattr) if ((scall->hl->lsmid->id) == lctx->id) { rc = scall->hl->hook.setselfattr(attr, lctx, size, flags); break; } free_out: kfree(lctx); return rc; } /** * security_getprocattr() - Read an attribute for a task * @p: the task * @lsmid: LSM identification * @name: attribute name * @value: attribute value * * Read attribute @name for task @p and store it into @value if allowed. * * Return: Returns the length of @value on success, a negative value otherwise. */ int security_getprocattr(struct task_struct *p, int lsmid, const char *name, char **value) { struct lsm_static_call *scall; lsm_for_each_hook(scall, getprocattr) { if (lsmid != 0 && lsmid != scall->hl->lsmid->id) continue; return scall->hl->hook.getprocattr(p, name, value); } return LSM_RET_DEFAULT(getprocattr); } /** * security_setprocattr() - Set an attribute for a task * @lsmid: LSM identification * @name: attribute name * @value: attribute value * @size: attribute value size * * Write (set) the current task's attribute @name to @value, size @size if * allowed. * * Return: Returns bytes written on success, a negative value otherwise. */ int security_setprocattr(int lsmid, const char *name, void *value, size_t size) { struct lsm_static_call *scall; lsm_for_each_hook(scall, setprocattr) { if (lsmid != 0 && lsmid != scall->hl->lsmid->id) continue; return scall->hl->hook.setprocattr(name, value, size); } return LSM_RET_DEFAULT(setprocattr); } /** * security_netlink_send() - Save info and check if netlink sending is allowed * @sk: sending socket * @skb: netlink message * * Save security information for a netlink message so that permission checking * can be performed when the message is processed. The security information * can be saved using the eff_cap field of the netlink_skb_parms structure. * Also may be used to provide fine grained control over message transmission. * * Return: Returns 0 if the information was successfully saved and message is * allowed to be transmitted. */ int security_netlink_send(struct sock *sk, struct sk_buff *skb) { return call_int_hook(netlink_send, sk, skb); } /** * security_ismaclabel() - Check if the named attribute is a MAC label * @name: full extended attribute name * * Check if the extended attribute specified by @name represents a MAC label. * * Return: Returns 1 if name is a MAC attribute otherwise returns 0. */ int security_ismaclabel(const char *name) { return call_int_hook(ismaclabel, name); } EXPORT_SYMBOL(security_ismaclabel); /** * security_secid_to_secctx() - Convert a secid to a secctx * @secid: secid * @secdata: secctx * @seclen: secctx length * * Convert secid to security context. If @secdata is NULL the length of the * result will be returned in @seclen, but no @secdata will be returned. This * does mean that the length could change between calls to check the length and * the next call which actually allocates and returns the @secdata. * * Return: Return 0 on success, error on failure. */ int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return call_int_hook(secid_to_secctx, secid, secdata, seclen); } EXPORT_SYMBOL(security_secid_to_secctx); /** * security_secctx_to_secid() - Convert a secctx to a secid * @secdata: secctx * @seclen: length of secctx * @secid: secid * * Convert security context to secid. * * Return: Returns 0 on success, error on failure. */ int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) { *secid = 0; return call_int_hook(secctx_to_secid, secdata, seclen, secid); } EXPORT_SYMBOL(security_secctx_to_secid); /** * security_release_secctx() - Free a secctx buffer * @secdata: secctx * @seclen: length of secctx * * Release the security context. */ void security_release_secctx(char *secdata, u32 seclen) { call_void_hook(release_secctx, secdata, seclen); } EXPORT_SYMBOL(security_release_secctx); /** * security_inode_invalidate_secctx() - Invalidate an inode's security label * @inode: inode * * Notify the security module that it must revalidate the security context of * an inode. */ void security_inode_invalidate_secctx(struct inode *inode) { call_void_hook(inode_invalidate_secctx, inode); } EXPORT_SYMBOL(security_inode_invalidate_secctx); /** * security_inode_notifysecctx() - Notify the LSM of an inode's security label * @inode: inode * @ctx: secctx * @ctxlen: length of secctx * * Notify the security module of what the security context of an inode should * be. Initializes the incore security context managed by the security module * for this inode. Example usage: NFS client invokes this hook to initialize * the security context in its incore inode to the value provided by the server * for the file when the server returned the file's attributes to the client. * Must be called with inode->i_mutex locked. * * Return: Returns 0 on success, error on failure. */ int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) { return call_int_hook(inode_notifysecctx, inode, ctx, ctxlen); } EXPORT_SYMBOL(security_inode_notifysecctx); /** * security_inode_setsecctx() - Change the security label of an inode * @dentry: inode * @ctx: secctx * @ctxlen: length of secctx * * Change the security context of an inode. Updates the incore security * context managed by the security module and invokes the fs code as needed * (via __vfs_setxattr_noperm) to update any backing xattrs that represent the * context. Example usage: NFS server invokes this hook to change the security * context in its incore inode and on the backing filesystem to a value * provided by the client on a SETATTR operation. Must be called with * inode->i_mutex locked. * * Return: Returns 0 on success, error on failure. */ int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) { return call_int_hook(inode_setsecctx, dentry, ctx, ctxlen); } EXPORT_SYMBOL(security_inode_setsecctx); /** * security_inode_getsecctx() - Get the security label of an inode * @inode: inode * @ctx: secctx * @ctxlen: length of secctx * * On success, returns 0 and fills out @ctx and @ctxlen with the security * context for the given @inode. * * Return: Returns 0 on success, error on failure. */ int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) { return call_int_hook(inode_getsecctx, inode, ctx, ctxlen); } EXPORT_SYMBOL(security_inode_getsecctx); #ifdef CONFIG_WATCH_QUEUE /** * security_post_notification() - Check if a watch notification can be posted * @w_cred: credentials of the task that set the watch * @cred: credentials of the task which triggered the watch * @n: the notification * * Check to see if a watch notification can be posted to a particular queue. * * Return: Returns 0 if permission is granted. */ int security_post_notification(const struct cred *w_cred, const struct cred *cred, struct watch_notification *n) { return call_int_hook(post_notification, w_cred, cred, n); } #endif /* CONFIG_WATCH_QUEUE */ #ifdef CONFIG_KEY_NOTIFICATIONS /** * security_watch_key() - Check if a task is allowed to watch for key events * @key: the key to watch * * Check to see if a process is allowed to watch for event notifications from * a key or keyring. * * Return: Returns 0 if permission is granted. */ int security_watch_key(struct key *key) { return call_int_hook(watch_key, key); } #endif /* CONFIG_KEY_NOTIFICATIONS */ #ifdef CONFIG_SECURITY_NETWORK /** * security_unix_stream_connect() - Check if a AF_UNIX stream is allowed * @sock: originating sock * @other: peer sock * @newsk: new sock * * Check permissions before establishing a Unix domain stream connection * between @sock and @other. * * The @unix_stream_connect and @unix_may_send hooks were necessary because * Linux provides an alternative to the conventional file name space for Unix * domain sockets. Whereas binding and connecting to sockets in the file name * space is mediated by the typical file permissions (and caught by the mknod * and permission hooks in inode_security_ops), binding and connecting to * sockets in the abstract name space is completely unmediated. Sufficient * control of Unix domain sockets in the abstract name space isn't possible * using only the socket layer hooks, since we need to know the actual target * socket, which is not looked up until we are inside the af_unix code. * * Return: Returns 0 if permission is granted. */ int security_unix_stream_connect(struct sock *sock, struct sock *other, struct sock *newsk) { return call_int_hook(unix_stream_connect, sock, other, newsk); } EXPORT_SYMBOL(security_unix_stream_connect); /** * security_unix_may_send() - Check if AF_UNIX socket can send datagrams * @sock: originating sock * @other: peer sock * * Check permissions before connecting or sending datagrams from @sock to * @other. * * The @unix_stream_connect and @unix_may_send hooks were necessary because * Linux provides an alternative to the conventional file name space for Unix * domain sockets. Whereas binding and connecting to sockets in the file name * space is mediated by the typical file permissions (and caught by the mknod * and permission hooks in inode_security_ops), binding and connecting to * sockets in the abstract name space is completely unmediated. Sufficient * control of Unix domain sockets in the abstract name space isn't possible * using only the socket layer hooks, since we need to know the actual target * socket, which is not looked up until we are inside the af_unix code. * * Return: Returns 0 if permission is granted. */ int security_unix_may_send(struct socket *sock, struct socket *other) { return call_int_hook(unix_may_send, sock, other); } EXPORT_SYMBOL(security_unix_may_send); /** * security_socket_create() - Check if creating a new socket is allowed * @family: protocol family * @type: communications type * @protocol: requested protocol * @kern: set to 1 if a kernel socket is requested * * Check permissions prior to creating a new socket. * * Return: Returns 0 if permission is granted. */ int security_socket_create(int family, int type, int protocol, int kern) { return call_int_hook(socket_create, family, type, protocol, kern); } /** * security_socket_post_create() - Initialize a newly created socket * @sock: socket * @family: protocol family * @type: communications type * @protocol: requested protocol * @kern: set to 1 if a kernel socket is requested * * This hook allows a module to update or allocate a per-socket security * structure. Note that the security field was not added directly to the socket * structure, but rather, the socket security information is stored in the * associated inode. Typically, the inode alloc_security hook will allocate * and attach security information to SOCK_INODE(sock)->i_security. This hook * may be used to update the SOCK_INODE(sock)->i_security field with additional * information that wasn't available when the inode was allocated. * * Return: Returns 0 if permission is granted. */ int security_socket_post_create(struct socket *sock, int family, int type, int protocol, int kern) { return call_int_hook(socket_post_create, sock, family, type, protocol, kern); } /** * security_socket_socketpair() - Check if creating a socketpair is allowed * @socka: first socket * @sockb: second socket * * Check permissions before creating a fresh pair of sockets. * * Return: Returns 0 if permission is granted and the connection was * established. */ int security_socket_socketpair(struct socket *socka, struct socket *sockb) { return call_int_hook(socket_socketpair, socka, sockb); } EXPORT_SYMBOL(security_socket_socketpair); /** * security_socket_bind() - Check if a socket bind operation is allowed * @sock: socket * @address: requested bind address * @addrlen: length of address * * Check permission before socket protocol layer bind operation is performed * and the socket @sock is bound to the address specified in the @address * parameter. * * Return: Returns 0 if permission is granted. */ int security_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) { return call_int_hook(socket_bind, sock, address, addrlen); } /** * security_socket_connect() - Check if a socket connect operation is allowed * @sock: socket * @address: address of remote connection point * @addrlen: length of address * * Check permission before socket protocol layer connect operation attempts to * connect socket @sock to a remote address, @address. * * Return: Returns 0 if permission is granted. */ int security_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) { return call_int_hook(socket_connect, sock, address, addrlen); } /** * security_socket_listen() - Check if a socket is allowed to listen * @sock: socket * @backlog: connection queue size * * Check permission before socket protocol layer listen operation. * * Return: Returns 0 if permission is granted. */ int security_socket_listen(struct socket *sock, int backlog) { return call_int_hook(socket_listen, sock, backlog); } /** * security_socket_accept() - Check if a socket is allowed to accept connections * @sock: listening socket * @newsock: newly creation connection socket * * Check permission before accepting a new connection. Note that the new * socket, @newsock, has been created and some information copied to it, but * the accept operation has not actually been performed. * * Return: Returns 0 if permission is granted. */ int security_socket_accept(struct socket *sock, struct socket *newsock) { return call_int_hook(socket_accept, sock, newsock); } /** * security_socket_sendmsg() - Check if sending a message is allowed * @sock: sending socket * @msg: message to send * @size: size of message * * Check permission before transmitting a message to another socket. * * Return: Returns 0 if permission is granted. */ int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) { return call_int_hook(socket_sendmsg, sock, msg, size); } /** * security_socket_recvmsg() - Check if receiving a message is allowed * @sock: receiving socket * @msg: message to receive * @size: size of message * @flags: operational flags * * Check permission before receiving a message from a socket. * * Return: Returns 0 if permission is granted. */ int security_socket_recvmsg(struct socket *sock, struct msghdr *msg, int size, int flags) { return call_int_hook(socket_recvmsg, sock, msg, size, flags); } /** * security_socket_getsockname() - Check if reading the socket addr is allowed * @sock: socket * * Check permission before reading the local address (name) of the socket * object. * * Return: Returns 0 if permission is granted. */ int security_socket_getsockname(struct socket *sock) { return call_int_hook(socket_getsockname, sock); } /** * security_socket_getpeername() - Check if reading the peer's addr is allowed * @sock: socket * * Check permission before the remote address (name) of a socket object. * * Return: Returns 0 if permission is granted. */ int security_socket_getpeername(struct socket *sock) { return call_int_hook(socket_getpeername, sock); } /** * security_socket_getsockopt() - Check if reading a socket option is allowed * @sock: socket * @level: option's protocol level * @optname: option name * * Check permissions before retrieving the options associated with socket * @sock. * * Return: Returns 0 if permission is granted. */ int security_socket_getsockopt(struct socket *sock, int level, int optname) { return call_int_hook(socket_getsockopt, sock, level, optname); } /** * security_socket_setsockopt() - Check if setting a socket option is allowed * @sock: socket * @level: option's protocol level * @optname: option name * * Check permissions before setting the options associated with socket @sock. * * Return: Returns 0 if permission is granted. */ int security_socket_setsockopt(struct socket *sock, int level, int optname) { return call_int_hook(socket_setsockopt, sock, level, optname); } /** * security_socket_shutdown() - Checks if shutting down the socket is allowed * @sock: socket * @how: flag indicating how sends and receives are handled * * Checks permission before all or part of a connection on the socket @sock is * shut down. * * Return: Returns 0 if permission is granted. */ int security_socket_shutdown(struct socket *sock, int how) { return call_int_hook(socket_shutdown, sock, how); } /** * security_sock_rcv_skb() - Check if an incoming network packet is allowed * @sk: destination sock * @skb: incoming packet * * Check permissions on incoming network packets. This hook is distinct from * Netfilter's IP input hooks since it is the first time that the incoming * sk_buff @skb has been associated with a particular socket, @sk. Must not * sleep inside this hook because some callers hold spinlocks. * * Return: Returns 0 if permission is granted. */ int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) { return call_int_hook(socket_sock_rcv_skb, sk, skb); } EXPORT_SYMBOL(security_sock_rcv_skb); /** * security_socket_getpeersec_stream() - Get the remote peer label * @sock: socket * @optval: destination buffer * @optlen: size of peer label copied into the buffer * @len: maximum size of the destination buffer * * This hook allows the security module to provide peer socket security state * for unix or connected tcp sockets to userspace via getsockopt SO_GETPEERSEC. * For tcp sockets this can be meaningful if the socket is associated with an * ipsec SA. * * Return: Returns 0 if all is well, otherwise, typical getsockopt return * values. */ int security_socket_getpeersec_stream(struct socket *sock, sockptr_t optval, sockptr_t optlen, unsigned int len) { return call_int_hook(socket_getpeersec_stream, sock, optval, optlen, len); } /** * security_socket_getpeersec_dgram() - Get the remote peer label * @sock: socket * @skb: datagram packet * @secid: remote peer label secid * * This hook allows the security module to provide peer socket security state * for udp sockets on a per-packet basis to userspace via getsockopt * SO_GETPEERSEC. The application must first have indicated the IP_PASSSEC * option via getsockopt. It can then retrieve the security state returned by * this hook for a packet via the SCM_SECURITY ancillary message type. * * Return: Returns 0 on success, error on failure. */ int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) { return call_int_hook(socket_getpeersec_dgram, sock, skb, secid); } EXPORT_SYMBOL(security_socket_getpeersec_dgram); /** * lsm_sock_alloc - allocate a composite sock blob * @sock: the sock that needs a blob * @gfp: allocation mode * * Allocate the sock blob for all the modules * * Returns 0, or -ENOMEM if memory can't be allocated. */ static int lsm_sock_alloc(struct sock *sock, gfp_t gfp) { return lsm_blob_alloc(&sock->sk_security, blob_sizes.lbs_sock, gfp); } /** * security_sk_alloc() - Allocate and initialize a sock's LSM blob * @sk: sock * @family: protocol family * @priority: gfp flags * * Allocate and attach a security structure to the sk->sk_security field, which * is used to copy security attributes between local stream sockets. * * Return: Returns 0 on success, error on failure. */ int security_sk_alloc(struct sock *sk, int family, gfp_t priority) { int rc = lsm_sock_alloc(sk, priority); if (unlikely(rc)) return rc; rc = call_int_hook(sk_alloc_security, sk, family, priority); if (unlikely(rc)) security_sk_free(sk); return rc; } /** * security_sk_free() - Free the sock's LSM blob * @sk: sock * * Deallocate security structure. */ void security_sk_free(struct sock *sk) { call_void_hook(sk_free_security, sk); kfree(sk->sk_security); sk->sk_security = NULL; } /** * security_sk_clone() - Clone a sock's LSM state * @sk: original sock * @newsk: target sock * * Clone/copy security structure. */ void security_sk_clone(const struct sock *sk, struct sock *newsk) { call_void_hook(sk_clone_security, sk, newsk); } EXPORT_SYMBOL(security_sk_clone); /** * security_sk_classify_flow() - Set a flow's secid based on socket * @sk: original socket * @flic: target flow * * Set the target flow's secid to socket's secid. */ void security_sk_classify_flow(const struct sock *sk, struct flowi_common *flic) { call_void_hook(sk_getsecid, sk, &flic->flowic_secid); } EXPORT_SYMBOL(security_sk_classify_flow); /** * security_req_classify_flow() - Set a flow's secid based on request_sock * @req: request_sock * @flic: target flow * * Sets @flic's secid to @req's secid. */ void security_req_classify_flow(const struct request_sock *req, struct flowi_common *flic) { call_void_hook(req_classify_flow, req, flic); } EXPORT_SYMBOL(security_req_classify_flow); /** * security_sock_graft() - Reconcile LSM state when grafting a sock on a socket * @sk: sock being grafted * @parent: target parent socket * * Sets @parent's inode secid to @sk's secid and update @sk with any necessary * LSM state from @parent. */ void security_sock_graft(struct sock *sk, struct socket *parent) { call_void_hook(sock_graft, sk, parent); } EXPORT_SYMBOL(security_sock_graft); /** * security_inet_conn_request() - Set request_sock state using incoming connect * @sk: parent listening sock * @skb: incoming connection * @req: new request_sock * * Initialize the @req LSM state based on @sk and the incoming connect in @skb. * * Return: Returns 0 if permission is granted. */ int security_inet_conn_request(const struct sock *sk, struct sk_buff *skb, struct request_sock *req) { return call_int_hook(inet_conn_request, sk, skb, req); } EXPORT_SYMBOL(security_inet_conn_request); /** * security_inet_csk_clone() - Set new sock LSM state based on request_sock * @newsk: new sock * @req: connection request_sock * * Set that LSM state of @sock using the LSM state from @req. */ void security_inet_csk_clone(struct sock *newsk, const struct request_sock *req) { call_void_hook(inet_csk_clone, newsk, req); } /** * security_inet_conn_established() - Update sock's LSM state with connection * @sk: sock * @skb: connection packet * * Update @sock's LSM state to represent a new connection from @skb. */ void security_inet_conn_established(struct sock *sk, struct sk_buff *skb) { call_void_hook(inet_conn_established, sk, skb); } EXPORT_SYMBOL(security_inet_conn_established); /** * security_secmark_relabel_packet() - Check if setting a secmark is allowed * @secid: new secmark value * * Check if the process should be allowed to relabel packets to @secid. * * Return: Returns 0 if permission is granted. */ int security_secmark_relabel_packet(u32 secid) { return call_int_hook(secmark_relabel_packet, secid); } EXPORT_SYMBOL(security_secmark_relabel_packet); /** * security_secmark_refcount_inc() - Increment the secmark labeling rule count * * Tells the LSM to increment the number of secmark labeling rules loaded. */ void security_secmark_refcount_inc(void) { call_void_hook(secmark_refcount_inc); } EXPORT_SYMBOL(security_secmark_refcount_inc); /** * security_secmark_refcount_dec() - Decrement the secmark labeling rule count * * Tells the LSM to decrement the number of secmark labeling rules loaded. */ void security_secmark_refcount_dec(void) { call_void_hook(secmark_refcount_dec); } EXPORT_SYMBOL(security_secmark_refcount_dec); /** * security_tun_dev_alloc_security() - Allocate a LSM blob for a TUN device * @security: pointer to the LSM blob * * This hook allows a module to allocate a security structure for a TUN device, * returning the pointer in @security. * * Return: Returns a zero on success, negative values on failure. */ int security_tun_dev_alloc_security(void **security) { int rc; rc = lsm_blob_alloc(security, blob_sizes.lbs_tun_dev, GFP_KERNEL); if (rc) return rc; rc = call_int_hook(tun_dev_alloc_security, *security); if (rc) { kfree(*security); *security = NULL; } return rc; } EXPORT_SYMBOL(security_tun_dev_alloc_security); /** * security_tun_dev_free_security() - Free a TUN device LSM blob * @security: LSM blob * * This hook allows a module to free the security structure for a TUN device. */ void security_tun_dev_free_security(void *security) { kfree(security); } EXPORT_SYMBOL(security_tun_dev_free_security); /** * security_tun_dev_create() - Check if creating a TUN device is allowed * * Check permissions prior to creating a new TUN device. * * Return: Returns 0 if permission is granted. */ int security_tun_dev_create(void) { return call_int_hook(tun_dev_create); } EXPORT_SYMBOL(security_tun_dev_create); /** * security_tun_dev_attach_queue() - Check if attaching a TUN queue is allowed * @security: TUN device LSM blob * * Check permissions prior to attaching to a TUN device queue. * * Return: Returns 0 if permission is granted. */ int security_tun_dev_attach_queue(void *security) { return call_int_hook(tun_dev_attach_queue, security); } EXPORT_SYMBOL(security_tun_dev_attach_queue); /** * security_tun_dev_attach() - Update TUN device LSM state on attach * @sk: associated sock * @security: TUN device LSM blob * * This hook can be used by the module to update any security state associated * with the TUN device's sock structure. * * Return: Returns 0 if permission is granted. */ int security_tun_dev_attach(struct sock *sk, void *security) { return call_int_hook(tun_dev_attach, sk, security); } EXPORT_SYMBOL(security_tun_dev_attach); /** * security_tun_dev_open() - Update TUN device LSM state on open * @security: TUN device LSM blob * * This hook can be used by the module to update any security state associated * with the TUN device's security structure. * * Return: Returns 0 if permission is granted. */ int security_tun_dev_open(void *security) { return call_int_hook(tun_dev_open, security); } EXPORT_SYMBOL(security_tun_dev_open); /** * security_sctp_assoc_request() - Update the LSM on a SCTP association req * @asoc: SCTP association * @skb: packet requesting the association * * Passes the @asoc and @chunk->skb of the association INIT packet to the LSM. * * Return: Returns 0 on success, error on failure. */ int security_sctp_assoc_request(struct sctp_association *asoc, struct sk_buff *skb) { return call_int_hook(sctp_assoc_request, asoc, skb); } EXPORT_SYMBOL(security_sctp_assoc_request); /** * security_sctp_bind_connect() - Validate a list of addrs for a SCTP option * @sk: socket * @optname: SCTP option to validate * @address: list of IP addresses to validate * @addrlen: length of the address list * * Validiate permissions required for each address associated with sock @sk. * Depending on @optname, the addresses will be treated as either a connect or * bind service. The @addrlen is calculated on each IPv4 and IPv6 address using * sizeof(struct sockaddr_in) or sizeof(struct sockaddr_in6). * * Return: Returns 0 on success, error on failure. */ int security_sctp_bind_connect(struct sock *sk, int optname, struct sockaddr *address, int addrlen) { return call_int_hook(sctp_bind_connect, sk, optname, address, addrlen); } EXPORT_SYMBOL(security_sctp_bind_connect); /** * security_sctp_sk_clone() - Clone a SCTP sock's LSM state * @asoc: SCTP association * @sk: original sock * @newsk: target sock * * Called whenever a new socket is created by accept(2) (i.e. a TCP style * socket) or when a socket is 'peeled off' e.g userspace calls * sctp_peeloff(3). */ void security_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, struct sock *newsk) { call_void_hook(sctp_sk_clone, asoc, sk, newsk); } EXPORT_SYMBOL(security_sctp_sk_clone); /** * security_sctp_assoc_established() - Update LSM state when assoc established * @asoc: SCTP association * @skb: packet establishing the association * * Passes the @asoc and @chunk->skb of the association COOKIE_ACK packet to the * security module. * * Return: Returns 0 if permission is granted. */ int security_sctp_assoc_established(struct sctp_association *asoc, struct sk_buff *skb) { return call_int_hook(sctp_assoc_established, asoc, skb); } EXPORT_SYMBOL(security_sctp_assoc_established); /** * security_mptcp_add_subflow() - Inherit the LSM label from the MPTCP socket * @sk: the owning MPTCP socket * @ssk: the new subflow * * Update the labeling for the given MPTCP subflow, to match the one of the * owning MPTCP socket. This hook has to be called after the socket creation and * initialization via the security_socket_create() and * security_socket_post_create() LSM hooks. * * Return: Returns 0 on success or a negative error code on failure. */ int security_mptcp_add_subflow(struct sock *sk, struct sock *ssk) { return call_int_hook(mptcp_add_subflow, sk, ssk); } #endif /* CONFIG_SECURITY_NETWORK */ #ifdef CONFIG_SECURITY_INFINIBAND /** * security_ib_pkey_access() - Check if access to an IB pkey is allowed * @sec: LSM blob * @subnet_prefix: subnet prefix of the port * @pkey: IB pkey * * Check permission to access a pkey when modifying a QP. * * Return: Returns 0 if permission is granted. */ int security_ib_pkey_access(void *sec, u64 subnet_prefix, u16 pkey) { return call_int_hook(ib_pkey_access, sec, subnet_prefix, pkey); } EXPORT_SYMBOL(security_ib_pkey_access); /** * security_ib_endport_manage_subnet() - Check if SMPs traffic is allowed * @sec: LSM blob * @dev_name: IB device name * @port_num: port number * * Check permissions to send and receive SMPs on a end port. * * Return: Returns 0 if permission is granted. */ int security_ib_endport_manage_subnet(void *sec, const char *dev_name, u8 port_num) { return call_int_hook(ib_endport_manage_subnet, sec, dev_name, port_num); } EXPORT_SYMBOL(security_ib_endport_manage_subnet); /** * security_ib_alloc_security() - Allocate an Infiniband LSM blob * @sec: LSM blob * * Allocate a security structure for Infiniband objects. * * Return: Returns 0 on success, non-zero on failure. */ int security_ib_alloc_security(void **sec) { int rc; rc = lsm_blob_alloc(sec, blob_sizes.lbs_ib, GFP_KERNEL); if (rc) return rc; rc = call_int_hook(ib_alloc_security, *sec); if (rc) { kfree(*sec); *sec = NULL; } return rc; } EXPORT_SYMBOL(security_ib_alloc_security); /** * security_ib_free_security() - Free an Infiniband LSM blob * @sec: LSM blob * * Deallocate an Infiniband security structure. */ void security_ib_free_security(void *sec) { kfree(sec); } EXPORT_SYMBOL(security_ib_free_security); #endif /* CONFIG_SECURITY_INFINIBAND */ #ifdef CONFIG_SECURITY_NETWORK_XFRM /** * security_xfrm_policy_alloc() - Allocate a xfrm policy LSM blob * @ctxp: xfrm security context being added to the SPD * @sec_ctx: security label provided by userspace * @gfp: gfp flags * * Allocate a security structure to the xp->security field; the security field * is initialized to NULL when the xfrm_policy is allocated. * * Return: Return 0 if operation was successful. */ int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, struct xfrm_user_sec_ctx *sec_ctx, gfp_t gfp) { return call_int_hook(xfrm_policy_alloc_security, ctxp, sec_ctx, gfp); } EXPORT_SYMBOL(security_xfrm_policy_alloc); /** * security_xfrm_policy_clone() - Clone xfrm policy LSM state * @old_ctx: xfrm security context * @new_ctxp: target xfrm security context * * Allocate a security structure in new_ctxp that contains the information from * the old_ctx structure. * * Return: Return 0 if operation was successful. */ int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, struct xfrm_sec_ctx **new_ctxp) { return call_int_hook(xfrm_policy_clone_security, old_ctx, new_ctxp); } /** * security_xfrm_policy_free() - Free a xfrm security context * @ctx: xfrm security context * * Free LSM resources associated with @ctx. */ void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx) { call_void_hook(xfrm_policy_free_security, ctx); } EXPORT_SYMBOL(security_xfrm_policy_free); /** * security_xfrm_policy_delete() - Check if deleting a xfrm policy is allowed * @ctx: xfrm security context * * Authorize deletion of a SPD entry. * * Return: Returns 0 if permission is granted. */ int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx) { return call_int_hook(xfrm_policy_delete_security, ctx); } /** * security_xfrm_state_alloc() - Allocate a xfrm state LSM blob * @x: xfrm state being added to the SAD * @sec_ctx: security label provided by userspace * * Allocate a security structure to the @x->security field; the security field * is initialized to NULL when the xfrm_state is allocated. Set the context to * correspond to @sec_ctx. * * Return: Return 0 if operation was successful. */ int security_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx) { return call_int_hook(xfrm_state_alloc, x, sec_ctx); } EXPORT_SYMBOL(security_xfrm_state_alloc); /** * security_xfrm_state_alloc_acquire() - Allocate a xfrm state LSM blob * @x: xfrm state being added to the SAD * @polsec: associated policy's security context * @secid: secid from the flow * * Allocate a security structure to the x->security field; the security field * is initialized to NULL when the xfrm_state is allocated. Set the context to * correspond to secid. * * Return: Returns 0 if operation was successful. */ int security_xfrm_state_alloc_acquire(struct xfrm_state *x, struct xfrm_sec_ctx *polsec, u32 secid) { return call_int_hook(xfrm_state_alloc_acquire, x, polsec, secid); } /** * security_xfrm_state_delete() - Check if deleting a xfrm state is allowed * @x: xfrm state * * Authorize deletion of x->security. * * Return: Returns 0 if permission is granted. */ int security_xfrm_state_delete(struct xfrm_state *x) { return call_int_hook(xfrm_state_delete_security, x); } EXPORT_SYMBOL(security_xfrm_state_delete); /** * security_xfrm_state_free() - Free a xfrm state * @x: xfrm state * * Deallocate x->security. */ void security_xfrm_state_free(struct xfrm_state *x) { call_void_hook(xfrm_state_free_security, x); } /** * security_xfrm_policy_lookup() - Check if using a xfrm policy is allowed * @ctx: target xfrm security context * @fl_secid: flow secid used to authorize access * * Check permission when a flow selects a xfrm_policy for processing XFRMs on a * packet. The hook is called when selecting either a per-socket policy or a * generic xfrm policy. * * Return: Return 0 if permission is granted, -ESRCH otherwise, or -errno on * other errors. */ int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid) { return call_int_hook(xfrm_policy_lookup, ctx, fl_secid); } /** * security_xfrm_state_pol_flow_match() - Check for a xfrm match * @x: xfrm state to match * @xp: xfrm policy to check for a match * @flic: flow to check for a match. * * Check @xp and @flic for a match with @x. * * Return: Returns 1 if there is a match. */ int security_xfrm_state_pol_flow_match(struct xfrm_state *x, struct xfrm_policy *xp, const struct flowi_common *flic) { struct lsm_static_call *scall; int rc = LSM_RET_DEFAULT(xfrm_state_pol_flow_match); /* * Since this function is expected to return 0 or 1, the judgment * becomes difficult if multiple LSMs supply this call. Fortunately, * we can use the first LSM's judgment because currently only SELinux * supplies this call. * * For speed optimization, we explicitly break the loop rather than * using the macro */ lsm_for_each_hook(scall, xfrm_state_pol_flow_match) { rc = scall->hl->hook.xfrm_state_pol_flow_match(x, xp, flic); break; } return rc; } /** * security_xfrm_decode_session() - Determine the xfrm secid for a packet * @skb: xfrm packet * @secid: secid * * Decode the packet in @skb and return the security label in @secid. * * Return: Return 0 if all xfrms used have the same secid. */ int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid) { return call_int_hook(xfrm_decode_session, skb, secid, 1); } void security_skb_classify_flow(struct sk_buff *skb, struct flowi_common *flic) { int rc = call_int_hook(xfrm_decode_session, skb, &flic->flowic_secid, 0); BUG_ON(rc); } EXPORT_SYMBOL(security_skb_classify_flow); #endif /* CONFIG_SECURITY_NETWORK_XFRM */ #ifdef CONFIG_KEYS /** * security_key_alloc() - Allocate and initialize a kernel key LSM blob * @key: key * @cred: credentials * @flags: allocation flags * * Permit allocation of a key and assign security data. Note that key does not * have a serial number assigned at this point. * * Return: Return 0 if permission is granted, -ve error otherwise. */ int security_key_alloc(struct key *key, const struct cred *cred, unsigned long flags) { int rc = lsm_key_alloc(key); if (unlikely(rc)) return rc; rc = call_int_hook(key_alloc, key, cred, flags); if (unlikely(rc)) security_key_free(key); return rc; } /** * security_key_free() - Free a kernel key LSM blob * @key: key * * Notification of destruction; free security data. */ void security_key_free(struct key *key) { kfree(key->security); key->security = NULL; } /** * security_key_permission() - Check if a kernel key operation is allowed * @key_ref: key reference * @cred: credentials of actor requesting access * @need_perm: requested permissions * * See whether a specific operational right is granted to a process on a key. * * Return: Return 0 if permission is granted, -ve error otherwise. */ int security_key_permission(key_ref_t key_ref, const struct cred *cred, enum key_need_perm need_perm) { return call_int_hook(key_permission, key_ref, cred, need_perm); } /** * security_key_getsecurity() - Get the key's security label * @key: key * @buffer: security label buffer * * Get a textual representation of the security context attached to a key for * the purposes of honouring KEYCTL_GETSECURITY. This function allocates the * storage for the NUL-terminated string and the caller should free it. * * Return: Returns the length of @buffer (including terminating NUL) or -ve if * an error occurs. May also return 0 (and a NULL buffer pointer) if * there is no security label assigned to the key. */ int security_key_getsecurity(struct key *key, char **buffer) { *buffer = NULL; return call_int_hook(key_getsecurity, key, buffer); } /** * security_key_post_create_or_update() - Notification of key create or update * @keyring: keyring to which the key is linked to * @key: created or updated key * @payload: data used to instantiate or update the key * @payload_len: length of payload * @flags: key flags * @create: flag indicating whether the key was created or updated * * Notify the caller of a key creation or update. */ void security_key_post_create_or_update(struct key *keyring, struct key *key, const void *payload, size_t payload_len, unsigned long flags, bool create) { call_void_hook(key_post_create_or_update, keyring, key, payload, payload_len, flags, create); } #endif /* CONFIG_KEYS */ #ifdef CONFIG_AUDIT /** * security_audit_rule_init() - Allocate and init an LSM audit rule struct * @field: audit action * @op: rule operator * @rulestr: rule context * @lsmrule: receive buffer for audit rule struct * @gfp: GFP flag used for kmalloc * * Allocate and initialize an LSM audit rule structure. * * Return: Return 0 if @lsmrule has been successfully set, -EINVAL in case of * an invalid rule. */ int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule, gfp_t gfp) { return call_int_hook(audit_rule_init, field, op, rulestr, lsmrule, gfp); } /** * security_audit_rule_known() - Check if an audit rule contains LSM fields * @krule: audit rule * * Specifies whether given @krule contains any fields related to the current * LSM. * * Return: Returns 1 in case of relation found, 0 otherwise. */ int security_audit_rule_known(struct audit_krule *krule) { return call_int_hook(audit_rule_known, krule); } /** * security_audit_rule_free() - Free an LSM audit rule struct * @lsmrule: audit rule struct * * Deallocate the LSM audit rule structure previously allocated by * audit_rule_init(). */ void security_audit_rule_free(void *lsmrule) { call_void_hook(audit_rule_free, lsmrule); } /** * security_audit_rule_match() - Check if a label matches an audit rule * @secid: security label * @field: LSM audit field * @op: matching operator * @lsmrule: audit rule * * Determine if given @secid matches a rule previously approved by * security_audit_rule_known(). * * Return: Returns 1 if secid matches the rule, 0 if it does not, -ERRNO on * failure. */ int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule) { return call_int_hook(audit_rule_match, secid, field, op, lsmrule); } #endif /* CONFIG_AUDIT */ #ifdef CONFIG_BPF_SYSCALL /** * security_bpf() - Check if the bpf syscall operation is allowed * @cmd: command * @attr: bpf attribute * @size: size * * Do a initial check for all bpf syscalls after the attribute is copied into * the kernel. The actual security module can implement their own rules to * check the specific cmd they need. * * Return: Returns 0 if permission is granted. */ int security_bpf(int cmd, union bpf_attr *attr, unsigned int size) { return call_int_hook(bpf, cmd, attr, size); } /** * security_bpf_map() - Check if access to a bpf map is allowed * @map: bpf map * @fmode: mode * * Do a check when the kernel generates and returns a file descriptor for eBPF * maps. * * Return: Returns 0 if permission is granted. */ int security_bpf_map(struct bpf_map *map, fmode_t fmode) { return call_int_hook(bpf_map, map, fmode); } /** * security_bpf_prog() - Check if access to a bpf program is allowed * @prog: bpf program * * Do a check when the kernel generates and returns a file descriptor for eBPF * programs. * * Return: Returns 0 if permission is granted. */ int security_bpf_prog(struct bpf_prog *prog) { return call_int_hook(bpf_prog, prog); } /** * security_bpf_map_create() - Check if BPF map creation is allowed * @map: BPF map object * @attr: BPF syscall attributes used to create BPF map * @token: BPF token used to grant user access * * Do a check when the kernel creates a new BPF map. This is also the * point where LSM blob is allocated for LSMs that need them. * * Return: Returns 0 on success, error on failure. */ int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, struct bpf_token *token) { return call_int_hook(bpf_map_create, map, attr, token); } /** * security_bpf_prog_load() - Check if loading of BPF program is allowed * @prog: BPF program object * @attr: BPF syscall attributes used to create BPF program * @token: BPF token used to grant user access to BPF subsystem * * Perform an access control check when the kernel loads a BPF program and * allocates associated BPF program object. This hook is also responsible for * allocating any required LSM state for the BPF program. * * Return: Returns 0 on success, error on failure. */ int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, struct bpf_token *token) { return call_int_hook(bpf_prog_load, prog, attr, token); } /** * security_bpf_token_create() - Check if creating of BPF token is allowed * @token: BPF token object * @attr: BPF syscall attributes used to create BPF token * @path: path pointing to BPF FS mount point from which BPF token is created * * Do a check when the kernel instantiates a new BPF token object from BPF FS * instance. This is also the point where LSM blob can be allocated for LSMs. * * Return: Returns 0 on success, error on failure. */ int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, const struct path *path) { return call_int_hook(bpf_token_create, token, attr, path); } /** * security_bpf_token_cmd() - Check if BPF token is allowed to delegate * requested BPF syscall command * @token: BPF token object * @cmd: BPF syscall command requested to be delegated by BPF token * * Do a check when the kernel decides whether provided BPF token should allow * delegation of requested BPF syscall command. * * Return: Returns 0 on success, error on failure. */ int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) { return call_int_hook(bpf_token_cmd, token, cmd); } /** * security_bpf_token_capable() - Check if BPF token is allowed to delegate * requested BPF-related capability * @token: BPF token object * @cap: capabilities requested to be delegated by BPF token * * Do a check when the kernel decides whether provided BPF token should allow * delegation of requested BPF-related capabilities. * * Return: Returns 0 on success, error on failure. */ int security_bpf_token_capable(const struct bpf_token *token, int cap) { return call_int_hook(bpf_token_capable, token, cap); } /** * security_bpf_map_free() - Free a bpf map's LSM blob * @map: bpf map * * Clean up the security information stored inside bpf map. */ void security_bpf_map_free(struct bpf_map *map) { call_void_hook(bpf_map_free, map); } /** * security_bpf_prog_free() - Free a BPF program's LSM blob * @prog: BPF program struct * * Clean up the security information stored inside BPF program. */ void security_bpf_prog_free(struct bpf_prog *prog) { call_void_hook(bpf_prog_free, prog); } /** * security_bpf_token_free() - Free a BPF token's LSM blob * @token: BPF token struct * * Clean up the security information stored inside BPF token. */ void security_bpf_token_free(struct bpf_token *token) { call_void_hook(bpf_token_free, token); } #endif /* CONFIG_BPF_SYSCALL */ /** * security_locked_down() - Check if a kernel feature is allowed * @what: requested kernel feature * * Determine whether a kernel feature that potentially enables arbitrary code * execution in kernel space should be permitted. * * Return: Returns 0 if permission is granted. */ int security_locked_down(enum lockdown_reason what) { return call_int_hook(locked_down, what); } EXPORT_SYMBOL(security_locked_down); /** * security_bdev_alloc() - Allocate a block device LSM blob * @bdev: block device * * Allocate and attach a security structure to @bdev->bd_security. The * security field is initialized to NULL when the bdev structure is * allocated. * * Return: Return 0 if operation was successful. */ int security_bdev_alloc(struct block_device *bdev) { int rc = 0; rc = lsm_bdev_alloc(bdev); if (unlikely(rc)) return rc; rc = call_int_hook(bdev_alloc_security, bdev); if (unlikely(rc)) security_bdev_free(bdev); return rc; } EXPORT_SYMBOL(security_bdev_alloc); /** * security_bdev_free() - Free a block device's LSM blob * @bdev: block device * * Deallocate the bdev security structure and set @bdev->bd_security to NULL. */ void security_bdev_free(struct block_device *bdev) { if (!bdev->bd_security) return; call_void_hook(bdev_free_security, bdev); kfree(bdev->bd_security); bdev->bd_security = NULL; } EXPORT_SYMBOL(security_bdev_free); /** * security_bdev_setintegrity() - Set the device's integrity data * @bdev: block device * @type: type of integrity, e.g. hash digest, signature, etc * @value: the integrity value * @size: size of the integrity value * * Register a verified integrity measurement of a bdev with LSMs. * LSMs should free the previously saved data if @value is NULL. * Please note that the new hook should be invoked every time the security * information is updated to keep these data current. For example, in dm-verity, * if the mapping table is reloaded and configured to use a different dm-verity * target with a new roothash and signing information, the previously stored * data in the LSM blob will become obsolete. It is crucial to re-invoke the * hook to refresh these data and ensure they are up to date. This necessity * arises from the design of device-mapper, where a device-mapper device is * first created, and then targets are subsequently loaded into it. These * targets can be modified multiple times during the device's lifetime. * Therefore, while the LSM blob is allocated during the creation of the block * device, its actual contents are not initialized at this stage and can change * substantially over time. This includes alterations from data that the LSMs * 'trusts' to those they do not, making it essential to handle these changes * correctly. Failure to address this dynamic aspect could potentially allow * for bypassing LSM checks. * * Return: Returns 0 on success, negative values on failure. */ int security_bdev_setintegrity(struct block_device *bdev, enum lsm_integrity_type type, const void *value, size_t size) { return call_int_hook(bdev_setintegrity, bdev, type, value, size); } EXPORT_SYMBOL(security_bdev_setintegrity); #ifdef CONFIG_PERF_EVENTS /** * security_perf_event_open() - Check if a perf event open is allowed * @attr: perf event attribute * @type: type of event * * Check whether the @type of perf_event_open syscall is allowed. * * Return: Returns 0 if permission is granted. */ int security_perf_event_open(struct perf_event_attr *attr, int type) { return call_int_hook(perf_event_open, attr, type); } /** * security_perf_event_alloc() - Allocate a perf event LSM blob * @event: perf event * * Allocate and save perf_event security info. * * Return: Returns 0 on success, error on failure. */ int security_perf_event_alloc(struct perf_event *event) { int rc; rc = lsm_blob_alloc(&event->security, blob_sizes.lbs_perf_event, GFP_KERNEL); if (rc) return rc; rc = call_int_hook(perf_event_alloc, event); if (rc) { kfree(event->security); event->security = NULL; } return rc; } /** * security_perf_event_free() - Free a perf event LSM blob * @event: perf event * * Release (free) perf_event security info. */ void security_perf_event_free(struct perf_event *event) { kfree(event->security); event->security = NULL; } /** * security_perf_event_read() - Check if reading a perf event label is allowed * @event: perf event * * Read perf_event security info if allowed. * * Return: Returns 0 if permission is granted. */ int security_perf_event_read(struct perf_event *event) { return call_int_hook(perf_event_read, event); } /** * security_perf_event_write() - Check if writing a perf event label is allowed * @event: perf event * * Write perf_event security info if allowed. * * Return: Returns 0 if permission is granted. */ int security_perf_event_write(struct perf_event *event) { return call_int_hook(perf_event_write, event); } #endif /* CONFIG_PERF_EVENTS */ #ifdef CONFIG_IO_URING /** * security_uring_override_creds() - Check if overriding creds is allowed * @new: new credentials * * Check if the current task, executing an io_uring operation, is allowed to * override it's credentials with @new. * * Return: Returns 0 if permission is granted. */ int security_uring_override_creds(const struct cred *new) { return call_int_hook(uring_override_creds, new); } /** * security_uring_sqpoll() - Check if IORING_SETUP_SQPOLL is allowed * * Check whether the current task is allowed to spawn a io_uring polling thread * (IORING_SETUP_SQPOLL). * * Return: Returns 0 if permission is granted. */ int security_uring_sqpoll(void) { return call_int_hook(uring_sqpoll); } /** * security_uring_cmd() - Check if a io_uring passthrough command is allowed * @ioucmd: command * * Check whether the file_operations uring_cmd is allowed to run. * * Return: Returns 0 if permission is granted. */ int security_uring_cmd(struct io_uring_cmd *ioucmd) { return call_int_hook(uring_cmd, ioucmd); } #endif /* CONFIG_IO_URING */ /** * security_initramfs_populated() - Notify LSMs that initramfs has been loaded * * Tells the LSMs the initramfs has been unpacked into the rootfs. */ void security_initramfs_populated(void) { call_void_hook(initramfs_populated); }