/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Mike Karels at Berkeley Software Design, Inc. * * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD * project, to make these variables more userfriendly. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94 */ #include #include "opt_capsicum.h" #include "opt_ddb.h" #include "opt_ktrace.h" #include "opt_sysctl.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #ifdef DDB #include #include #endif #include #include #include #include static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer"); RB_GENERATE(sysctl_oid_list, sysctl_oid, oid_link, cmp_sysctl_oid); /* * The sysctllock protects the MIB tree. It also protects sysctl * contexts used with dynamic sysctls. The sysctl_register_oid() and * sysctl_unregister_oid() routines require the sysctllock to already * be held, so the sysctl_wlock() and sysctl_wunlock() routines are * provided for the few places in the kernel which need to use that * API rather than using the dynamic API. Use of the dynamic API is * strongly encouraged for most code. * * The sysctlmemlock is used to limit the amount of user memory wired for * sysctl requests. This is implemented by serializing any userland * sysctl requests larger than a single page via an exclusive lock. * * The sysctlstringlock is used to protect concurrent access to writable * string nodes in sysctl_handle_string(). */ static struct rmlock sysctllock; static struct sx __exclusive_cache_line sysctlmemlock; static struct sx sysctlstringlock; #define SYSCTL_WLOCK() rm_wlock(&sysctllock) #define SYSCTL_WUNLOCK() rm_wunlock(&sysctllock) #define SYSCTL_RLOCK(tracker) rm_rlock(&sysctllock, (tracker)) #define SYSCTL_RUNLOCK(tracker) rm_runlock(&sysctllock, (tracker)) #define SYSCTL_WLOCKED() rm_wowned(&sysctllock) #define SYSCTL_ASSERT_LOCKED() rm_assert(&sysctllock, RA_LOCKED) #define SYSCTL_ASSERT_WLOCKED() rm_assert(&sysctllock, RA_WLOCKED) #define SYSCTL_ASSERT_RLOCKED() rm_assert(&sysctllock, RA_RLOCKED) #define SYSCTL_INIT() rm_init_flags(&sysctllock, "sysctl lock", \ RM_SLEEPABLE) #define SYSCTL_SLEEP(ch, wmesg, timo) \ rm_sleep(ch, &sysctllock, 0, wmesg, timo) static int sysctl_root(SYSCTL_HANDLER_ARGS); /* Root list */ struct sysctl_oid_list sysctl__children = RB_INITIALIZER(&sysctl__children); static char* sysctl_escape_name(const char*); static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse); static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t); static int sysctl_new_kernel(struct sysctl_req *, void *, size_t); static struct sysctl_oid * sysctl_find_oidname(const char *name, struct sysctl_oid_list *list) { struct sysctl_oid *oidp; SYSCTL_ASSERT_LOCKED(); SYSCTL_FOREACH(oidp, list) { if (strcmp(oidp->oid_name, name) == 0) { return (oidp); } } return (NULL); } /* * Initialization of the MIB tree. * * Order by number in each list. */ void sysctl_wlock(void) { SYSCTL_WLOCK(); } void sysctl_wunlock(void) { SYSCTL_WUNLOCK(); } static int sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intmax_t arg2, struct sysctl_req *req, struct rm_priotracker *tracker) { int error; if (oid->oid_kind & CTLFLAG_DYN) atomic_add_int(&oid->oid_running, 1); if (tracker != NULL) SYSCTL_RUNLOCK(tracker); else SYSCTL_WUNLOCK(); /* * Treat set CTLFLAG_NEEDGIANT and unset CTLFLAG_MPSAFE flags the same, * untill we're ready to remove all traces of Giant from sysctl(9). */ if ((oid->oid_kind & CTLFLAG_NEEDGIANT) || (!(oid->oid_kind & CTLFLAG_MPSAFE))) mtx_lock(&Giant); error = oid->oid_handler(oid, arg1, arg2, req); if ((oid->oid_kind & CTLFLAG_NEEDGIANT) || (!(oid->oid_kind & CTLFLAG_MPSAFE))) mtx_unlock(&Giant); KFAIL_POINT_ERROR(_debug_fail_point, sysctl_running, error); if (tracker != NULL) SYSCTL_RLOCK(tracker); else SYSCTL_WLOCK(); if (oid->oid_kind & CTLFLAG_DYN) { if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 && (oid->oid_kind & CTLFLAG_DYING) != 0) wakeup(&oid->oid_running); } return (error); } static void sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp) { struct sysctl_req req; struct sysctl_oid *curr; char *penv = NULL; char path[96]; ssize_t rem = sizeof(path); ssize_t len; uint8_t data[512] __aligned(sizeof(uint64_t)); int size; int error; path[--rem] = 0; for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) { len = strlen(curr->oid_name); rem -= len; if (curr != oidp) rem -= 1; if (rem < 0) { printf("OID path exceeds %d bytes\n", (int)sizeof(path)); return; } memcpy(path + rem, curr->oid_name, len); if (curr != oidp) path[rem + len] = '.'; } memset(&req, 0, sizeof(req)); req.td = curthread; req.oldfunc = sysctl_old_kernel; req.newfunc = sysctl_new_kernel; req.lock = REQ_UNWIRED; switch (oidp->oid_kind & CTLTYPE) { case CTLTYPE_INT: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(int), GETENV_SIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_UINT: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(int), GETENV_UNSIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_LONG: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(long), GETENV_SIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_ULONG: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(long), GETENV_UNSIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_S8: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(int8_t), GETENV_SIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_S16: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(int16_t), GETENV_SIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_S32: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(int32_t), GETENV_SIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_S64: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(int64_t), GETENV_SIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_U8: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(uint8_t), GETENV_UNSIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_U16: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(uint16_t), GETENV_UNSIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_U32: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(uint32_t), GETENV_UNSIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_U64: if (getenv_array(path + rem, data, sizeof(data), &size, sizeof(uint64_t), GETENV_UNSIGNED) == 0) return; req.newlen = size; req.newptr = data; break; case CTLTYPE_STRING: penv = kern_getenv(path + rem); if (penv == NULL) return; req.newlen = strlen(penv); req.newptr = penv; break; default: return; } error = sysctl_root_handler_locked(oidp, oidp->oid_arg1, oidp->oid_arg2, &req, NULL); if (error != 0) printf("Setting sysctl %s failed: %d\n", path + rem, error); if (penv != NULL) freeenv(penv); } /* * Locate the path to a given oid. Returns the length of the resulting path, * or -1 if the oid was not found. nodes must have room for CTL_MAXNAME * elements. */ static int sysctl_search_oid(struct sysctl_oid **nodes, struct sysctl_oid *needle) { int indx; SYSCTL_ASSERT_LOCKED(); indx = 0; /* * Do a depth-first search of the oid tree, looking for 'needle'. Start * with the first child of the root. */ nodes[indx] = RB_MIN(sysctl_oid_list, &sysctl__children); for (;;) { if (nodes[indx] == needle) return (indx + 1); if (nodes[indx] == NULL) { /* Node has no more siblings, so back up to parent. */ if (indx-- == 0) { /* Retreat to root, so give up. */ break; } } else if ((nodes[indx]->oid_kind & CTLTYPE) == CTLTYPE_NODE) { /* Node has children. */ if (++indx == CTL_MAXNAME) { /* Max search depth reached, so give up. */ break; } /* Start with the first child. */ nodes[indx] = RB_MIN(sysctl_oid_list, &nodes[indx - 1]->oid_children); continue; } /* Consider next sibling. */ nodes[indx] = RB_NEXT(sysctl_oid_list, NULL, nodes[indx]); } return (-1); } static void sysctl_warn_reuse(const char *func, struct sysctl_oid *leaf) { struct sysctl_oid *nodes[CTL_MAXNAME]; char buf[128]; struct sbuf sb; int rc, i; (void)sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN | SBUF_INCLUDENUL); sbuf_set_drain(&sb, sbuf_printf_drain, NULL); sbuf_printf(&sb, "%s: can't re-use a leaf (", __func__); rc = sysctl_search_oid(nodes, leaf); if (rc > 0) { for (i = 0; i < rc; i++) sbuf_printf(&sb, "%s%.*s", nodes[i]->oid_name, i != (rc - 1), "."); } else { sbuf_printf(&sb, "%s", leaf->oid_name); } sbuf_printf(&sb, ")!\n"); (void)sbuf_finish(&sb); } #ifdef SYSCTL_DEBUG static int sysctl_reuse_test(SYSCTL_HANDLER_ARGS) { struct rm_priotracker tracker; SYSCTL_RLOCK(&tracker); sysctl_warn_reuse(__func__, oidp); SYSCTL_RUNLOCK(&tracker); return (0); } SYSCTL_PROC(_sysctl, OID_AUTO, reuse_test, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, sysctl_reuse_test, "-", ""); #endif void sysctl_register_oid(struct sysctl_oid *oidp) { struct sysctl_oid_list *parent = oidp->oid_parent; struct sysctl_oid *p, key; int oid_number; int timeout = 2; /* * First check if another oid with the same name already * exists in the parent's list. */ SYSCTL_ASSERT_WLOCKED(); p = sysctl_find_oidname(oidp->oid_name, parent); if (p != NULL) { if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { p->oid_refcnt++; return; } else { sysctl_warn_reuse(__func__, p); return; } } /* get current OID number */ oid_number = oidp->oid_number; #if (OID_AUTO >= 0) #error "OID_AUTO is expected to be a negative value" #endif /* * Any negative OID number qualifies as OID_AUTO. Valid OID * numbers should always be positive. * * NOTE: DO NOT change the starting value here, change it in * , and make sure it is at least 256 to * accommodate e.g. net.inet.raw as a static sysctl node. */ if (oid_number < 0) { static int newoid; /* * By decrementing the next OID number we spend less * time inserting the OIDs into a sorted list. */ if (--newoid < CTL_AUTO_START) newoid = 0x7fffffff; oid_number = newoid; } /* * Insert the OID into the parent's list sorted by OID number. */ key.oid_number = oid_number; p = RB_NFIND(sysctl_oid_list, parent, &key); while (p != NULL && oid_number == p->oid_number) { /* get the next valid OID number */ if (oid_number < CTL_AUTO_START || oid_number == 0x7fffffff) { /* wraparound - restart */ oid_number = CTL_AUTO_START; /* don't loop forever */ if (!timeout--) panic("sysctl: Out of OID numbers\n"); key.oid_number = oid_number; p = RB_NFIND(sysctl_oid_list, parent, &key); continue; } p = RB_NEXT(sysctl_oid_list, NULL, p); oid_number++; } /* check for non-auto OID number collision */ if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START && oid_number >= CTL_AUTO_START) { printf("sysctl: OID number(%d) is already in use for '%s'\n", oidp->oid_number, oidp->oid_name); } /* update the OID number, if any */ oidp->oid_number = oid_number; RB_INSERT(sysctl_oid_list, parent, oidp); if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE && #ifdef VIMAGE (oidp->oid_kind & CTLFLAG_VNET) == 0 && #endif (oidp->oid_kind & CTLFLAG_TUN) != 0 && (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) { /* only fetch value once */ oidp->oid_kind |= CTLFLAG_NOFETCH; /* try to fetch value from kernel environment */ sysctl_load_tunable_by_oid_locked(oidp); } } void sysctl_register_disabled_oid(struct sysctl_oid *oidp) { /* * Mark the leaf as dormant if it's not to be immediately enabled. * We do not disable nodes as they can be shared between modules * and it is always safe to access a node. */ KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, ("internal flag is set in oid_kind")); if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) oidp->oid_kind |= CTLFLAG_DORMANT; sysctl_register_oid(oidp); } void sysctl_enable_oid(struct sysctl_oid *oidp) { SYSCTL_ASSERT_WLOCKED(); if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, ("sysctl node is marked as dormant")); return; } KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) != 0, ("enabling already enabled sysctl oid")); oidp->oid_kind &= ~CTLFLAG_DORMANT; } void sysctl_unregister_oid(struct sysctl_oid *oidp) { int error; SYSCTL_ASSERT_WLOCKED(); if (oidp->oid_number == OID_AUTO) { error = EINVAL; } else { error = ENOENT; if (RB_REMOVE(sysctl_oid_list, oidp->oid_parent, oidp)) error = 0; } /* * This can happen when a module fails to register and is * being unloaded afterwards. It should not be a panic() * for normal use. */ if (error) { printf("%s: failed(%d) to unregister sysctl(%s)\n", __func__, error, oidp->oid_name); } } /* Initialize a new context to keep track of dynamically added sysctls. */ int sysctl_ctx_init(struct sysctl_ctx_list *c) { if (c == NULL) { return (EINVAL); } /* * No locking here, the caller is responsible for not adding * new nodes to a context until after this function has * returned. */ TAILQ_INIT(c); return (0); } /* Free the context, and destroy all dynamic oids registered in this context */ int sysctl_ctx_free(struct sysctl_ctx_list *clist) { struct sysctl_ctx_entry *e, *e1; int error; error = 0; /* * First perform a "dry run" to check if it's ok to remove oids. * XXX FIXME * XXX This algorithm is a hack. But I don't know any * XXX better solution for now... */ SYSCTL_WLOCK(); TAILQ_FOREACH(e, clist, link) { error = sysctl_remove_oid_locked(e->entry, 0, 0); if (error) break; } /* * Restore deregistered entries, either from the end, * or from the place where error occurred. * e contains the entry that was not unregistered */ if (error) e1 = TAILQ_PREV(e, sysctl_ctx_list, link); else e1 = TAILQ_LAST(clist, sysctl_ctx_list); while (e1 != NULL) { sysctl_register_oid(e1->entry); e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); } if (error) { SYSCTL_WUNLOCK(); return(EBUSY); } /* Now really delete the entries */ e = TAILQ_FIRST(clist); while (e != NULL) { e1 = TAILQ_NEXT(e, link); error = sysctl_remove_oid_locked(e->entry, 1, 0); if (error) panic("sysctl_remove_oid: corrupt tree, entry: %s", e->entry->oid_name); free(e, M_SYSCTLOID); e = e1; } SYSCTL_WUNLOCK(); return (error); } /* Add an entry to the context */ struct sysctl_ctx_entry * sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) { struct sysctl_ctx_entry *e; SYSCTL_ASSERT_WLOCKED(); if (clist == NULL || oidp == NULL) return(NULL); e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); e->entry = oidp; TAILQ_INSERT_HEAD(clist, e, link); return (e); } /* Find an entry in the context */ struct sysctl_ctx_entry * sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) { struct sysctl_ctx_entry *e; SYSCTL_ASSERT_WLOCKED(); if (clist == NULL || oidp == NULL) return(NULL); TAILQ_FOREACH(e, clist, link) { if (e->entry == oidp) return(e); } return (e); } /* * Delete an entry from the context. * NOTE: this function doesn't free oidp! You have to remove it * with sysctl_remove_oid(). */ int sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) { struct sysctl_ctx_entry *e; if (clist == NULL || oidp == NULL) return (EINVAL); SYSCTL_WLOCK(); e = sysctl_ctx_entry_find(clist, oidp); if (e != NULL) { TAILQ_REMOVE(clist, e, link); SYSCTL_WUNLOCK(); free(e, M_SYSCTLOID); return (0); } else { SYSCTL_WUNLOCK(); return (ENOENT); } } /* * Remove dynamically created sysctl trees. * oidp - top of the tree to be removed * del - if 0 - just deregister, otherwise free up entries as well * recurse - if != 0 traverse the subtree to be deleted */ int sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) { int error; SYSCTL_WLOCK(); error = sysctl_remove_oid_locked(oidp, del, recurse); SYSCTL_WUNLOCK(); return (error); } int sysctl_remove_name(struct sysctl_oid *parent, const char *name, int del, int recurse) { struct sysctl_oid *p; int error; error = ENOENT; SYSCTL_WLOCK(); p = sysctl_find_oidname(name, &parent->oid_children); if (p) error = sysctl_remove_oid_locked(p, del, recurse); SYSCTL_WUNLOCK(); return (error); } /* * Duplicate the provided string, escaping any illegal characters. The result * must be freed when no longer in use. * * The list of illegal characters is ".". */ static char* sysctl_escape_name(const char* orig) { int i, s = 0, d = 0, nillegals = 0; char *new; /* First count the number of illegal characters */ for (i = 0; orig[i] != '\0'; i++) { if (orig[i] == '.') nillegals++; } /* Allocate storage for new string */ new = malloc(i + 2 * nillegals + 1, M_SYSCTLOID, M_WAITOK); /* Copy the name, escaping characters as we go */ while (orig[s] != '\0') { if (orig[s] == '.') { /* %25 is the hexadecimal representation of '.' */ new[d++] = '%'; new[d++] = '2'; new[d++] = '5'; s++; } else { new[d++] = orig[s++]; } } /* Finally, nul-terminate */ new[d] = '\0'; return (new); } static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) { struct sysctl_oid *p, *tmp; int error; SYSCTL_ASSERT_WLOCKED(); if (oidp == NULL) return(EINVAL); if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { printf("Warning: can't remove non-dynamic nodes (%s)!\n", oidp->oid_name); return (EINVAL); } /* * WARNING: normal method to do this should be through * sysctl_ctx_free(). Use recursing as the last resort * method to purge your sysctl tree of leftovers... * However, if some other code still references these nodes, * it will panic. */ if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { if (oidp->oid_refcnt == 1) { for(p = RB_MIN(sysctl_oid_list, &oidp->oid_children); p != NULL; p = tmp) { if (!recurse) { printf("Warning: failed attempt to " "remove oid %s with child %s\n", oidp->oid_name, p->oid_name); return (ENOTEMPTY); } tmp = RB_NEXT(sysctl_oid_list, &oidp->oid_children, p); error = sysctl_remove_oid_locked(p, del, recurse); if (error) return (error); } } } if (oidp->oid_refcnt > 1 ) { oidp->oid_refcnt--; } else { if (oidp->oid_refcnt == 0) { printf("Warning: bad oid_refcnt=%u (%s)!\n", oidp->oid_refcnt, oidp->oid_name); return (EINVAL); } sysctl_unregister_oid(oidp); if (del) { /* * Wait for all threads running the handler to drain. * This preserves the previous behavior when the * sysctl lock was held across a handler invocation, * and is necessary for module unload correctness. */ while (oidp->oid_running > 0) { oidp->oid_kind |= CTLFLAG_DYING; SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); } if (oidp->oid_descr) free(__DECONST(char *, oidp->oid_descr), M_SYSCTLOID); if (oidp->oid_label) free(__DECONST(char *, oidp->oid_label), M_SYSCTLOID); free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); free(oidp, M_SYSCTLOID); } } return (0); } /* * Create new sysctls at run time. * clist may point to a valid context initialized with sysctl_ctx_init(). */ struct sysctl_oid * sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, int number, const char *name, int kind, void *arg1, intmax_t arg2, int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr, const char *label) { struct sysctl_oid *oidp; char *escaped; /* You have to hook up somewhere.. */ if (parent == NULL) return(NULL); escaped = sysctl_escape_name(name); /* Check if the node already exists, otherwise create it */ SYSCTL_WLOCK(); oidp = sysctl_find_oidname(escaped, parent); if (oidp != NULL) { free(escaped, M_SYSCTLOID); if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { oidp->oid_refcnt++; /* Update the context */ if (clist != NULL) sysctl_ctx_entry_add(clist, oidp); SYSCTL_WUNLOCK(); return (oidp); } else { sysctl_warn_reuse(__func__, oidp); SYSCTL_WUNLOCK(); return (NULL); } } oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); oidp->oid_parent = parent; RB_INIT(&oidp->oid_children); oidp->oid_number = number; oidp->oid_refcnt = 1; oidp->oid_name = escaped; oidp->oid_handler = handler; oidp->oid_kind = CTLFLAG_DYN | kind; oidp->oid_arg1 = arg1; oidp->oid_arg2 = arg2; oidp->oid_fmt = fmt; if (descr != NULL) oidp->oid_descr = strdup(descr, M_SYSCTLOID); if (label != NULL) oidp->oid_label = strdup(label, M_SYSCTLOID); /* Update the context, if used */ if (clist != NULL) sysctl_ctx_entry_add(clist, oidp); /* Register this oid */ sysctl_register_oid(oidp); SYSCTL_WUNLOCK(); return (oidp); } /* * Rename an existing oid. */ void sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) { char *newname; char *oldname; newname = strdup(name, M_SYSCTLOID); SYSCTL_WLOCK(); oldname = __DECONST(char *, oidp->oid_name); oidp->oid_name = newname; SYSCTL_WUNLOCK(); free(oldname, M_SYSCTLOID); } /* * Reparent an existing oid. */ int sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) { struct sysctl_oid *oidp; SYSCTL_WLOCK(); if (oid->oid_parent == parent) { SYSCTL_WUNLOCK(); return (0); } oidp = sysctl_find_oidname(oid->oid_name, parent); if (oidp != NULL) { SYSCTL_WUNLOCK(); return (EEXIST); } sysctl_unregister_oid(oid); oid->oid_parent = parent; oid->oid_number = OID_AUTO; sysctl_register_oid(oid); SYSCTL_WUNLOCK(); return (0); } /* * Register the kernel's oids on startup. */ SET_DECLARE(sysctl_set, struct sysctl_oid); static void sysctl_register_all(void *arg) { struct sysctl_oid **oidp; sx_init(&sysctlmemlock, "sysctl mem"); sx_init(&sysctlstringlock, "sysctl string handler"); SYSCTL_INIT(); SYSCTL_WLOCK(); SET_FOREACH(oidp, sysctl_set) sysctl_register_oid(*oidp); SYSCTL_WUNLOCK(); } SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, NULL); /* * "Staff-functions" * * These functions implement a presently undocumented interface * used by the sysctl program to walk the tree, and get the type * so it can print the value. * This interface is under work and consideration, and should probably * be killed with a big axe by the first person who can find the time. * (be aware though, that the proper interface isn't as obvious as it * may seem, there are various conflicting requirements. * * {CTL_SYSCTL, CTL_SYSCTL_DEBUG} printf the entire MIB-tree. * {CTL_SYSCTL, CTL_SYSCTL_NAME, ...} return the name of the "..." * OID. * {CTL_SYSCTL, CTL_SYSCTL_NEXT, ...} return the next OID, honoring * CTLFLAG_SKIP. * {CTL_SYSCTL, CTL_SYSCTL_NAME2OID} return the OID of the name in * "new" * {CTL_SYSCTL, CTL_SYSCTL_OIDFMT, ...} return the kind & format info * for the "..." OID. * {CTL_SYSCTL, CTL_SYSCTL_OIDDESCR, ...} return the description of the * "..." OID. * {CTL_SYSCTL, CTL_SYSCTL_OIDLABEL, ...} return the aggregation label of * the "..." OID. * {CTL_SYSCTL, CTL_SYSCTL_NEXTNOSKIP, ...} return the next OID, ignoring * CTLFLAG_SKIP. */ #ifdef SYSCTL_DEBUG static void sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) { int k; struct sysctl_oid *oidp; SYSCTL_ASSERT_LOCKED(); SYSCTL_FOREACH(oidp, l) { for (k=0; koid_number, oidp->oid_name); printf("%c%c", oidp->oid_kind & CTLFLAG_RD ? 'R':' ', oidp->oid_kind & CTLFLAG_WR ? 'W':' '); if (oidp->oid_handler) printf(" *Handler"); switch (oidp->oid_kind & CTLTYPE) { case CTLTYPE_NODE: printf(" Node\n"); if (!oidp->oid_handler) { sysctl_sysctl_debug_dump_node( SYSCTL_CHILDREN(oidp), i + 2); } break; case CTLTYPE_INT: printf(" Int\n"); break; case CTLTYPE_UINT: printf(" u_int\n"); break; case CTLTYPE_LONG: printf(" Long\n"); break; case CTLTYPE_ULONG: printf(" u_long\n"); break; case CTLTYPE_STRING: printf(" String\n"); break; case CTLTYPE_S8: printf(" int8_t\n"); break; case CTLTYPE_S16: printf(" int16_t\n"); break; case CTLTYPE_S32: printf(" int32_t\n"); break; case CTLTYPE_S64: printf(" int64_t\n"); break; case CTLTYPE_U8: printf(" uint8_t\n"); break; case CTLTYPE_U16: printf(" uint16_t\n"); break; case CTLTYPE_U32: printf(" uint32_t\n"); break; case CTLTYPE_U64: printf(" uint64_t\n"); break; case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; default: printf("\n"); } } } static int sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) { struct rm_priotracker tracker; int error; error = priv_check(req->td, PRIV_SYSCTL_DEBUG); if (error) return (error); SYSCTL_RLOCK(&tracker); sysctl_sysctl_debug_dump_node(&sysctl__children, 0); SYSCTL_RUNLOCK(&tracker); return (ENOENT); } SYSCTL_PROC(_sysctl, CTL_SYSCTL_DEBUG, debug, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, sysctl_sysctl_debug, "-", ""); #endif static int sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) { int *name = (int *) arg1; u_int namelen = arg2; int error; struct sysctl_oid *oid, key; struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; struct rm_priotracker tracker; char buf[10]; error = sysctl_wire_old_buffer(req, 0); if (error) return (error); SYSCTL_RLOCK(&tracker); while (namelen) { if (!lsp) { snprintf(buf,sizeof(buf),"%d",*name); if (req->oldidx) error = SYSCTL_OUT(req, ".", 1); if (!error) error = SYSCTL_OUT(req, buf, strlen(buf)); if (error) goto out; namelen--; name++; continue; } lsp2 = NULL; key.oid_number = *name; oid = RB_FIND(sysctl_oid_list, lsp, &key); if (oid) { if (req->oldidx) error = SYSCTL_OUT(req, ".", 1); if (!error) error = SYSCTL_OUT(req, oid->oid_name, strlen(oid->oid_name)); if (error) goto out; namelen--; name++; if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE && !oid->oid_handler) lsp2 = SYSCTL_CHILDREN(oid); } lsp = lsp2; } error = SYSCTL_OUT(req, "", 1); out: SYSCTL_RUNLOCK(&tracker); return (error); } /* * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in * capability mode. */ static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_name, ""); enum sysctl_iter_action { ITER_SIBLINGS, /* Not matched, continue iterating siblings */ ITER_CHILDREN, /* Node has children we need to iterate over them */ ITER_FOUND, /* Matching node was found */ }; /* * Tries to find the next node for @name and @namelen. * * Returns next action to take. */ static enum sysctl_iter_action sysctl_sysctl_next_node(struct sysctl_oid *oidp, int *name, unsigned int namelen, bool honor_skip) { if ((oidp->oid_kind & CTLFLAG_DORMANT) != 0) return (ITER_SIBLINGS); if (honor_skip && (oidp->oid_kind & CTLFLAG_SKIP) != 0) return (ITER_SIBLINGS); if (namelen == 0) { /* * We have reached a node with a full name match and are * looking for the next oid in its children. * * For CTL_SYSCTL_NEXTNOSKIP we are done. * * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it * has a handler) and move on to the children. */ if (!honor_skip) return (ITER_FOUND); if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) return (ITER_FOUND); /* If node does not have an iterator, treat it as leaf */ if (oidp->oid_handler) return (ITER_FOUND); /* Report oid as a node to iterate */ return (ITER_CHILDREN); } /* * No match yet. Continue seeking the given name. * * We are iterating in order by oid_number, so skip oids lower * than the one we are looking for. * * When the current oid_number is higher than the one we seek, * that means we have reached the next oid in the sequence and * should return it. * * If the oid_number matches the name at this level then we * have to find a node to continue searching at the next level. */ if (oidp->oid_number < *name) return (ITER_SIBLINGS); if (oidp->oid_number > *name) { /* * We have reached the next oid. * * For CTL_SYSCTL_NEXTNOSKIP we are done. * * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it * has a handler) and move on to the children. */ if (!honor_skip) return (ITER_FOUND); if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) return (ITER_FOUND); /* If node does not have an iterator, treat it as leaf */ if (oidp->oid_handler) return (ITER_FOUND); return (ITER_CHILDREN); } /* match at a current level */ if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) return (ITER_SIBLINGS); if (oidp->oid_handler) return (ITER_SIBLINGS); return (ITER_CHILDREN); } /* * Recursively walk the sysctl subtree at lsp until we find the given name. * Returns true and fills in next oid data in @next and @len if oid is found. */ static bool sysctl_sysctl_next_action(struct sysctl_oid_list *lsp, int *name, u_int namelen, int *next, int *len, int level, bool honor_skip) { struct sysctl_oid_list *next_lsp; struct sysctl_oid *oidp = NULL, key; bool success = false; enum sysctl_iter_action action; SYSCTL_ASSERT_LOCKED(); /* * Start the search at the requested oid. But if not found, then scan * through all children. */ if (namelen > 0) { key.oid_number = *name; oidp = RB_FIND(sysctl_oid_list, lsp, &key); } if (!oidp) oidp = RB_MIN(sysctl_oid_list, lsp); for(; oidp != NULL; oidp = RB_NEXT(sysctl_oid_list, lsp, oidp)) { action = sysctl_sysctl_next_node(oidp, name, namelen, honor_skip); if (action == ITER_SIBLINGS) continue; if (action == ITER_FOUND) { success = true; break; } KASSERT((action== ITER_CHILDREN), ("ret(%d)!=ITER_CHILDREN", action)); next_lsp = SYSCTL_CHILDREN(oidp); if (namelen == 0) { success = sysctl_sysctl_next_action(next_lsp, NULL, 0, next + 1, len, level + 1, honor_skip); } else { success = sysctl_sysctl_next_action(next_lsp, name + 1, namelen - 1, next + 1, len, level + 1, honor_skip); if (!success) { /* * We maintain the invariant that current node oid * is >= the oid provided in @name. * As there are no usable children at this node, * current node oid is strictly > than the requested * oid. * Hence, reduce namelen to 0 to allow for picking first * nodes/leafs in the next node in list. */ namelen = 0; } } if (success) break; } if (success) { *next = oidp->oid_number; if (level > *len) *len = level; } return (success); } static int sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) { int *name = (int *) arg1; u_int namelen = arg2; int len, error; bool success; struct sysctl_oid_list *lsp = &sysctl__children; struct rm_priotracker tracker; int next[CTL_MAXNAME]; len = 0; SYSCTL_RLOCK(&tracker); success = sysctl_sysctl_next_action(lsp, name, namelen, next, &len, 1, oidp->oid_number == CTL_SYSCTL_NEXT); SYSCTL_RUNLOCK(&tracker); if (!success) return (ENOENT); error = SYSCTL_OUT(req, next, len * sizeof (int)); return (error); } /* * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in * capability mode. */ static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXT, next, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXTNOSKIP, nextnoskip, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); static int name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) { struct sysctl_oid *oidp; struct sysctl_oid_list *lsp = &sysctl__children; SYSCTL_ASSERT_LOCKED(); for (*len = 0; *len < CTL_MAXNAME;) { oidp = sysctl_find_oidname(strsep(&name, "."), lsp); if (oidp == NULL) return (ENOENT); *oid++ = oidp->oid_number; (*len)++; if (name == NULL || *name == '\0') { if (oidpp) *oidpp = oidp; return (0); } if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) break; if (oidp->oid_handler) break; lsp = SYSCTL_CHILDREN(oidp); } return (ENOENT); } static int sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) { char *p; int error, oid[CTL_MAXNAME], len = 0; struct sysctl_oid *op = NULL; struct rm_priotracker tracker; char buf[32]; if (!req->newlen) return (ENOENT); if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ return (ENAMETOOLONG); p = buf; if (req->newlen >= sizeof(buf)) p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); error = SYSCTL_IN(req, p, req->newlen); if (error) { if (p != buf) free(p, M_SYSCTL); return (error); } p [req->newlen] = '\0'; SYSCTL_RLOCK(&tracker); error = name2oid(p, oid, &len, &op); SYSCTL_RUNLOCK(&tracker); if (p != buf) free(p, M_SYSCTL); if (error) return (error); error = SYSCTL_OUT(req, oid, len * sizeof *oid); return (error); } /* * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in * capability mode. */ SYSCTL_PROC(_sysctl, CTL_SYSCTL_NAME2OID, name2oid, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_MPSAFE | CTLFLAG_CAPRW, 0, 0, sysctl_sysctl_name2oid, "I", ""); static int sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) { struct sysctl_oid *oid; struct rm_priotracker tracker; int error; error = sysctl_wire_old_buffer(req, 0); if (error) return (error); SYSCTL_RLOCK(&tracker); error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); if (error) goto out; if (oid->oid_fmt == NULL) { error = ENOENT; goto out; } error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); if (error) goto out; error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); out: SYSCTL_RUNLOCK(&tracker); return (error); } static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDFMT, oidfmt, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidfmt, ""); static int sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) { struct sysctl_oid *oid; struct rm_priotracker tracker; int error; error = sysctl_wire_old_buffer(req, 0); if (error) return (error); SYSCTL_RLOCK(&tracker); error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); if (error) goto out; if (oid->oid_descr == NULL) { error = ENOENT; goto out; } error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); out: SYSCTL_RUNLOCK(&tracker); return (error); } static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDDESCR, oiddescr, CTLFLAG_RD | CTLFLAG_MPSAFE|CTLFLAG_CAPRD, sysctl_sysctl_oiddescr, ""); static int sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS) { struct sysctl_oid *oid; struct rm_priotracker tracker; int error; error = sysctl_wire_old_buffer(req, 0); if (error) return (error); SYSCTL_RLOCK(&tracker); error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); if (error) goto out; if (oid->oid_label == NULL) { error = ENOENT; goto out; } error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1); out: SYSCTL_RUNLOCK(&tracker); return (error); } static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDLABEL, oidlabel, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, ""); /* * Default "handler" functions. */ /* * Handle a bool. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_bool(SYSCTL_HANDLER_ARGS) { uint8_t temp; int error; /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) temp = *(bool *)arg1 ? 1 : 0; else temp = arg2 ? 1 : 0; error = SYSCTL_OUT(req, &temp, sizeof(temp)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; else { error = SYSCTL_IN(req, &temp, sizeof(temp)); if (!error) *(bool *)arg1 = temp ? 1 : 0; } return (error); } /* * Handle an int8_t, signed or unsigned. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_8(SYSCTL_HANDLER_ARGS) { int8_t tmpout; int error = 0; /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) tmpout = *(int8_t *)arg1; else tmpout = arg2; error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; else error = SYSCTL_IN(req, arg1, sizeof(tmpout)); return (error); } /* * Handle an int16_t, signed or unsigned. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_16(SYSCTL_HANDLER_ARGS) { int16_t tmpout; int error = 0; /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) tmpout = *(int16_t *)arg1; else tmpout = arg2; error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; else error = SYSCTL_IN(req, arg1, sizeof(tmpout)); return (error); } /* * Handle an int32_t, signed or unsigned. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_32(SYSCTL_HANDLER_ARGS) { int32_t tmpout; int error = 0; /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) tmpout = *(int32_t *)arg1; else tmpout = arg2; error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; else error = SYSCTL_IN(req, arg1, sizeof(tmpout)); return (error); } /* * Handle an int, signed or unsigned. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_int(SYSCTL_HANDLER_ARGS) { int tmpout, error = 0; /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) tmpout = *(int *)arg1; else tmpout = arg2; error = SYSCTL_OUT(req, &tmpout, sizeof(int)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; else error = SYSCTL_IN(req, arg1, sizeof(int)); return (error); } /* * Based on sysctl_handle_int() convert milliseconds into ticks. * Note: this is used by TCP. */ int sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) { int error, s, tt; tt = *(int *)arg1; s = (int)((int64_t)tt * 1000 / hz); error = sysctl_handle_int(oidp, &s, 0, req); if (error || !req->newptr) return (error); tt = (int)((int64_t)s * hz / 1000); if (tt < 1) return (EINVAL); *(int *)arg1 = tt; return (0); } /* * Handle a long, signed or unsigned. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_long(SYSCTL_HANDLER_ARGS) { int error = 0; long tmplong; #ifdef SCTL_MASK32 int tmpint; #endif /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) tmplong = *(long *)arg1; else tmplong = arg2; #ifdef SCTL_MASK32 if (req->flags & SCTL_MASK32) { tmpint = tmplong; error = SYSCTL_OUT(req, &tmpint, sizeof(int)); } else #endif error = SYSCTL_OUT(req, &tmplong, sizeof(long)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; #ifdef SCTL_MASK32 else if (req->flags & SCTL_MASK32) { error = SYSCTL_IN(req, &tmpint, sizeof(int)); *(long *)arg1 = (long)tmpint; } #endif else error = SYSCTL_IN(req, arg1, sizeof(long)); return (error); } /* * Handle a 64 bit int, signed or unsigned. * Two cases: * a variable: point arg1 at it. * a constant: pass it in arg2. */ int sysctl_handle_64(SYSCTL_HANDLER_ARGS) { int error = 0; uint64_t tmpout; /* * Attempt to get a coherent snapshot by making a copy of the data. */ if (arg1) tmpout = *(uint64_t *)arg1; else tmpout = arg2; error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); if (error || !req->newptr) return (error); if (!arg1) error = EPERM; else error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); return (error); } /* * Handle our generic '\0' terminated 'C' string. * Two cases: * a variable string: point arg1 at it, arg2 is max length. * a constant string: point arg1 at it, arg2 is zero. */ int sysctl_handle_string(SYSCTL_HANDLER_ARGS) { char *tmparg; size_t outlen; int error = 0, ro_string = 0; /* * If the sysctl isn't writable and isn't a preallocated tunable that * can be modified by kenv(2), microoptimise and treat it as a * read-only string. * A zero-length buffer indicates a fixed size read-only * string. In ddb, don't worry about trying to make a malloced * snapshot. */ if ((oidp->oid_kind & (CTLFLAG_WR | CTLFLAG_TUN)) == 0 || arg2 == 0 || kdb_active) { arg2 = strlen((char *)arg1) + 1; ro_string = 1; } if (req->oldptr != NULL) { if (ro_string) { tmparg = arg1; outlen = strlen(tmparg) + 1; } else { tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); sx_slock(&sysctlstringlock); memcpy(tmparg, arg1, arg2); sx_sunlock(&sysctlstringlock); outlen = strlen(tmparg) + 1; } error = SYSCTL_OUT(req, tmparg, outlen); if (!ro_string) free(tmparg, M_SYSCTLTMP); } else { if (!ro_string) sx_slock(&sysctlstringlock); outlen = strlen((char *)arg1) + 1; if (!ro_string) sx_sunlock(&sysctlstringlock); error = SYSCTL_OUT(req, NULL, outlen); } if (error || !req->newptr) return (error); if (req->newlen - req->newidx >= arg2 || req->newlen - req->newidx < 0) { error = EINVAL; } else if (req->newlen - req->newidx == 0) { sx_xlock(&sysctlstringlock); ((char *)arg1)[0] = '\0'; sx_xunlock(&sysctlstringlock); } else if (req->newfunc == sysctl_new_kernel) { arg2 = req->newlen - req->newidx; sx_xlock(&sysctlstringlock); error = SYSCTL_IN(req, arg1, arg2); if (error == 0) { ((char *)arg1)[arg2] = '\0'; req->newidx += arg2; } sx_xunlock(&sysctlstringlock); } else { arg2 = req->newlen - req->newidx; tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); error = SYSCTL_IN(req, tmparg, arg2); if (error) { free(tmparg, M_SYSCTLTMP); return (error); } sx_xlock(&sysctlstringlock); memcpy(arg1, tmparg, arg2); ((char *)arg1)[arg2] = '\0'; sx_xunlock(&sysctlstringlock); free(tmparg, M_SYSCTLTMP); req->newidx += arg2; } return (error); } /* * Handle any kind of opaque data. * arg1 points to it, arg2 is the size. */ int sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) { int error, tries; u_int generation; struct sysctl_req req2; /* * Attempt to get a coherent snapshot, by using the thread * pre-emption counter updated from within mi_switch() to * determine if we were pre-empted during a bcopy() or * copyout(). Make 3 attempts at doing this before giving up. * If we encounter an error, stop immediately. */ tries = 0; req2 = *req; retry: generation = curthread->td_generation; error = SYSCTL_OUT(req, arg1, arg2); if (error) return (error); tries++; if (generation != curthread->td_generation && tries < 3) { *req = req2; goto retry; } error = SYSCTL_IN(req, arg1, arg2); return (error); } /* * Based on sysctl_handle_64() convert microseconds to a sbintime. */ int sysctl_usec_to_sbintime(SYSCTL_HANDLER_ARGS) { int error; int64_t usec; usec = sbttous(*(sbintime_t *)arg1); error = sysctl_handle_64(oidp, &usec, 0, req); if (error || !req->newptr) return (error); *(sbintime_t *)arg1 = ustosbt(usec); return (0); } /* * Based on sysctl_handle_64() convert milliseconds to a sbintime. */ int sysctl_msec_to_sbintime(SYSCTL_HANDLER_ARGS) { int error; int64_t msec; msec = sbttoms(*(sbintime_t *)arg1); error = sysctl_handle_64(oidp, &msec, 0, req); if (error || !req->newptr) return (error); *(sbintime_t *)arg1 = mstosbt(msec); return (0); } /* * Convert seconds to a struct timeval. Intended for use with * intervals and thus does not permit negative seconds. */ int sysctl_sec_to_timeval(SYSCTL_HANDLER_ARGS) { struct timeval *tv; int error, secs; tv = arg1; secs = tv->tv_sec; error = sysctl_handle_int(oidp, &secs, 0, req); if (error || req->newptr == NULL) return (error); if (secs < 0) return (EINVAL); tv->tv_sec = secs; return (0); } /* * Transfer functions to/from kernel space. * XXX: rather untested at this point */ static int sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) { size_t i = 0; if (req->oldptr) { i = l; if (req->oldlen <= req->oldidx) i = 0; else if (i > req->oldlen - req->oldidx) i = req->oldlen - req->oldidx; if (i > 0) bcopy(p, (char *)req->oldptr + req->oldidx, i); } req->oldidx += l; if (req->oldptr && i != l) return (ENOMEM); return (0); } static int sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) { if (!req->newptr) return (0); if (req->newlen - req->newidx < l) return (EINVAL); bcopy((const char *)req->newptr + req->newidx, p, l); req->newidx += l; return (0); } int kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) { int error = 0; struct sysctl_req req; bzero(&req, sizeof req); req.td = td; req.flags = flags; if (oldlenp) { req.oldlen = *oldlenp; } req.validlen = req.oldlen; if (old) { req.oldptr= old; } if (new != NULL) { req.newlen = newlen; req.newptr = new; } req.oldfunc = sysctl_old_kernel; req.newfunc = sysctl_new_kernel; req.lock = REQ_UNWIRED; error = sysctl_root(0, name, namelen, &req); if (req.lock == REQ_WIRED && req.validlen > 0) vsunlock(req.oldptr, req.validlen); if (error && error != ENOMEM) return (error); if (retval) { if (req.oldptr && req.oldidx > req.validlen) *retval = req.validlen; else *retval = req.oldidx; } return (error); } int kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) { int oid[CTL_MAXNAME]; size_t oidlen, plen; int error; oid[0] = CTL_SYSCTL; oid[1] = CTL_SYSCTL_NAME2OID; oidlen = sizeof(oid); error = kernel_sysctl(td, oid, 2, oid, &oidlen, (void *)name, strlen(name), &plen, flags); if (error) return (error); error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, new, newlen, retval, flags); return (error); } /* * Transfer function to/from user space. */ static int sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) { size_t i, len, origidx; int error; origidx = req->oldidx; req->oldidx += l; if (req->oldptr == NULL) return (0); /* * If we have not wired the user supplied buffer and we are currently * holding locks, drop a witness warning, as it's possible that * write operations to the user page can sleep. */ if (req->lock != REQ_WIRED) WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "sysctl_old_user()"); i = l; len = req->validlen; if (len <= origidx) i = 0; else { if (i > len - origidx) i = len - origidx; if (req->lock == REQ_WIRED) { error = copyout_nofault(p, (char *)req->oldptr + origidx, i); } else error = copyout(p, (char *)req->oldptr + origidx, i); if (error != 0) return (error); } if (i < l) return (ENOMEM); return (0); } static int sysctl_new_user(struct sysctl_req *req, void *p, size_t l) { int error; if (!req->newptr) return (0); if (req->newlen - req->newidx < l) return (EINVAL); WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "sysctl_new_user()"); error = copyin((const char *)req->newptr + req->newidx, p, l); req->newidx += l; return (error); } /* * Wire the user space destination buffer. If set to a value greater than * zero, the len parameter limits the maximum amount of wired memory. */ int sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) { int ret; size_t wiredlen; wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; ret = 0; if (req->lock != REQ_WIRED && req->oldptr && req->oldfunc == sysctl_old_user) { if (wiredlen != 0) { ret = vslock(req->oldptr, wiredlen); if (ret != 0) { if (ret != ENOMEM) return (ret); wiredlen = 0; } } req->lock = REQ_WIRED; req->validlen = wiredlen; } return (0); } int sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, int *nindx, struct sysctl_req *req) { struct sysctl_oid_list *lsp; struct sysctl_oid *oid; struct sysctl_oid key; int indx; SYSCTL_ASSERT_LOCKED(); lsp = &sysctl__children; indx = 0; while (indx < CTL_MAXNAME) { key.oid_number = name[indx]; oid = RB_FIND(sysctl_oid_list, lsp, &key); if (oid == NULL) return (ENOENT); indx++; if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { if (oid->oid_handler != NULL || indx == namelen) { *noid = oid; if (nindx != NULL) *nindx = indx; KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, ("%s found DYING node %p", __func__, oid)); return (0); } lsp = SYSCTL_CHILDREN(oid); } else if (indx == namelen) { if ((oid->oid_kind & CTLFLAG_DORMANT) != 0) return (ENOENT); *noid = oid; if (nindx != NULL) *nindx = indx; KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, ("%s found DYING node %p", __func__, oid)); return (0); } else { return (ENOTDIR); } } return (ENOENT); } /* * Traverse our tree, and find the right node, execute whatever it points * to, and return the resulting error code. */ static int sysctl_root(SYSCTL_HANDLER_ARGS) { struct sysctl_oid *oid; struct rm_priotracker tracker; int error, indx, lvl; SYSCTL_RLOCK(&tracker); error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); if (error) goto out; if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { /* * You can't call a sysctl when it's a node, but has * no handler. Inform the user that it's a node. * The indx may or may not be the same as namelen. */ if (oid->oid_handler == NULL) { error = EISDIR; goto out; } } /* Is this sysctl writable? */ if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { error = EPERM; goto out; } KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); #ifdef CAPABILITY_MODE /* * If the process is in capability mode, then don't permit reading or * writing unless specifically granted for the node. */ if (IN_CAPABILITY_MODE(req->td)) { if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { error = EPERM; goto out; } } #endif /* Is this sysctl sensitive to securelevels? */ if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; error = securelevel_gt(req->td->td_ucred, lvl); if (error) goto out; } /* Is this sysctl writable by only privileged users? */ if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { int priv; if (oid->oid_kind & CTLFLAG_PRISON) priv = PRIV_SYSCTL_WRITEJAIL; #ifdef VIMAGE else if ((oid->oid_kind & CTLFLAG_VNET) && prison_owns_vnet(req->td->td_ucred)) priv = PRIV_SYSCTL_WRITEJAIL; #endif else priv = PRIV_SYSCTL_WRITE; error = priv_check(req->td, priv); if (error) goto out; } if (!oid->oid_handler) { error = EINVAL; goto out; } if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { arg1 = (int *)arg1 + indx; arg2 -= indx; } else { arg1 = oid->oid_arg1; arg2 = oid->oid_arg2; } #ifdef MAC error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, req); if (error != 0) goto out; #endif #ifdef VIMAGE if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); #endif error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); out: SYSCTL_RUNLOCK(&tracker); return (error); } #ifndef _SYS_SYSPROTO_H_ struct __sysctl_args { int *name; u_int namelen; void *old; size_t *oldlenp; void *new; size_t newlen; }; #endif int sys___sysctl(struct thread *td, struct __sysctl_args *uap) { int error, i, name[CTL_MAXNAME]; size_t j; if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) return (EINVAL); error = copyin(uap->name, &name, uap->namelen * sizeof(int)); if (error) return (error); error = userland_sysctl(td, name, uap->namelen, uap->old, uap->oldlenp, 0, uap->new, uap->newlen, &j, 0); if (error && error != ENOMEM) return (error); if (uap->oldlenp) { i = copyout(&j, uap->oldlenp, sizeof(j)); if (i) return (i); } return (error); } int kern___sysctlbyname(struct thread *td, const char *oname, size_t namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags, bool inkernel) { int oid[CTL_MAXNAME]; char namebuf[16]; char *name; size_t oidlen; int error; if (namelen > MAXPATHLEN || namelen == 0) return (EINVAL); name = namebuf; if (namelen > sizeof(namebuf)) name = malloc(namelen, M_SYSCTL, M_WAITOK); error = copyin(oname, name, namelen); if (error != 0) goto out; oid[0] = CTL_SYSCTL; oid[1] = CTL_SYSCTL_NAME2OID; oidlen = sizeof(oid); error = kernel_sysctl(td, oid, 2, oid, &oidlen, (void *)name, namelen, retval, flags); if (error != 0) goto out; error = userland_sysctl(td, oid, *retval / sizeof(int), old, oldlenp, inkernel, new, newlen, retval, flags); out: if (namelen > sizeof(namebuf)) free(name, M_SYSCTL); return (error); } #ifndef _SYS_SYSPROTO_H_ struct __sysctlbyname_args { const char *name; size_t namelen; void *old; size_t *oldlenp; void *new; size_t newlen; }; #endif int sys___sysctlbyname(struct thread *td, struct __sysctlbyname_args *uap) { size_t rv; int error; error = kern___sysctlbyname(td, uap->name, uap->namelen, uap->old, uap->oldlenp, uap->new, uap->newlen, &rv, 0, 0); if (error != 0) return (error); if (uap->oldlenp != NULL) error = copyout(&rv, uap->oldlenp, sizeof(rv)); return (error); } /* * This is used from various compatibility syscalls too. That's why name * must be in kernel space. */ int userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, const void *new, size_t newlen, size_t *retval, int flags) { int error = 0, memlocked; struct sysctl_req req; bzero(&req, sizeof req); req.td = td; req.flags = flags; if (oldlenp) { if (inkernel) { req.oldlen = *oldlenp; } else { error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); if (error) return (error); } } req.validlen = req.oldlen; req.oldptr = old; if (new != NULL) { req.newlen = newlen; req.newptr = new; } req.oldfunc = sysctl_old_user; req.newfunc = sysctl_new_user; req.lock = REQ_UNWIRED; #ifdef KTRACE if (KTRPOINT(curthread, KTR_SYSCTL)) ktrsysctl(name, namelen); #endif memlocked = 0; if (req.oldptr && req.oldlen > 4 * PAGE_SIZE) { memlocked = 1; sx_xlock(&sysctlmemlock); } CURVNET_SET(TD_TO_VNET(td)); for (;;) { req.oldidx = 0; req.newidx = 0; error = sysctl_root(0, name, namelen, &req); if (error != EAGAIN) break; kern_yield(PRI_USER); } CURVNET_RESTORE(); if (req.lock == REQ_WIRED && req.validlen > 0) vsunlock(req.oldptr, req.validlen); if (memlocked) sx_xunlock(&sysctlmemlock); if (error && error != ENOMEM) return (error); if (retval) { if (req.oldptr && req.oldidx > req.validlen) *retval = req.validlen; else *retval = req.oldidx; } return (error); } /* * Drain into a sysctl struct. The user buffer should be wired if a page * fault would cause issue. */ static int sbuf_sysctl_drain(void *arg, const char *data, int len) { struct sysctl_req *req = arg; int error; error = SYSCTL_OUT(req, data, len); KASSERT(error >= 0, ("Got unexpected negative value %d", error)); return (error == 0 ? len : -error); } struct sbuf * sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, struct sysctl_req *req) { /* Supply a default buffer size if none given. */ if (buf == NULL && length == 0) length = 64; s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); sbuf_set_drain(s, sbuf_sysctl_drain, req); return (s); } #ifdef DDB /* The current OID the debugger is working with */ static struct sysctl_oid *g_ddb_oid; /* The current flags specified by the user */ static int g_ddb_sysctl_flags; /* Check to see if the last sysctl printed */ static int g_ddb_sysctl_printed; static const int ctl_sign[CTLTYPE+1] = { [CTLTYPE_INT] = 1, [CTLTYPE_LONG] = 1, [CTLTYPE_S8] = 1, [CTLTYPE_S16] = 1, [CTLTYPE_S32] = 1, [CTLTYPE_S64] = 1, }; static const int ctl_size[CTLTYPE+1] = { [CTLTYPE_INT] = sizeof(int), [CTLTYPE_UINT] = sizeof(u_int), [CTLTYPE_LONG] = sizeof(long), [CTLTYPE_ULONG] = sizeof(u_long), [CTLTYPE_S8] = sizeof(int8_t), [CTLTYPE_S16] = sizeof(int16_t), [CTLTYPE_S32] = sizeof(int32_t), [CTLTYPE_S64] = sizeof(int64_t), [CTLTYPE_U8] = sizeof(uint8_t), [CTLTYPE_U16] = sizeof(uint16_t), [CTLTYPE_U32] = sizeof(uint32_t), [CTLTYPE_U64] = sizeof(uint64_t), }; #define DB_SYSCTL_NAME_ONLY 0x001 /* Compare with -N */ #define DB_SYSCTL_VALUE_ONLY 0x002 /* Compare with -n */ #define DB_SYSCTL_OPAQUE 0x004 /* Compare with -o */ #define DB_SYSCTL_HEX 0x008 /* Compare with -x */ #define DB_SYSCTL_SAFE_ONLY 0x100 /* Only simple types */ static const char db_sysctl_modifs[] = { 'N', 'n', 'o', 'x', }; static const int db_sysctl_modif_values[] = { DB_SYSCTL_NAME_ONLY, DB_SYSCTL_VALUE_ONLY, DB_SYSCTL_OPAQUE, DB_SYSCTL_HEX, }; /* Handlers considered safe to print while recursing */ static int (* const db_safe_handlers[])(SYSCTL_HANDLER_ARGS) = { sysctl_handle_bool, sysctl_handle_8, sysctl_handle_16, sysctl_handle_32, sysctl_handle_64, sysctl_handle_int, sysctl_handle_long, sysctl_handle_string, sysctl_handle_opaque, }; /* * Use in place of sysctl_old_kernel to print sysctl values. * * Compare to the output handling in show_var from sbin/sysctl/sysctl.c */ static int sysctl_old_ddb(struct sysctl_req *req, const void *ptr, size_t len) { const u_char *val, *p; const char *sep1; size_t intlen, slen; uintmax_t umv; intmax_t mv; int sign, ctltype, hexlen, xflag, error; /* Suppress false-positive GCC uninitialized variable warnings */ mv = 0; umv = 0; slen = len; val = p = ptr; if (ptr == NULL) { error = 0; goto out; } /* We are going to print */ g_ddb_sysctl_printed = 1; xflag = g_ddb_sysctl_flags & DB_SYSCTL_HEX; ctltype = (g_ddb_oid->oid_kind & CTLTYPE); sign = ctl_sign[ctltype]; intlen = ctl_size[ctltype]; switch (ctltype) { case CTLTYPE_NODE: case CTLTYPE_STRING: db_printf("%.*s", (int) len, (const char *) p); error = 0; goto out; case CTLTYPE_INT: case CTLTYPE_UINT: case CTLTYPE_LONG: case CTLTYPE_ULONG: case CTLTYPE_S8: case CTLTYPE_S16: case CTLTYPE_S32: case CTLTYPE_S64: case CTLTYPE_U8: case CTLTYPE_U16: case CTLTYPE_U32: case CTLTYPE_U64: hexlen = 2 + (intlen * CHAR_BIT + 3) / 4; sep1 = ""; while (len >= intlen) { switch (ctltype) { case CTLTYPE_INT: case CTLTYPE_UINT: umv = *(const u_int *)p; mv = *(const int *)p; break; case CTLTYPE_LONG: case CTLTYPE_ULONG: umv = *(const u_long *)p; mv = *(const long *)p; break; case CTLTYPE_S8: case CTLTYPE_U8: umv = *(const uint8_t *)p; mv = *(const int8_t *)p; break; case CTLTYPE_S16: case CTLTYPE_U16: umv = *(const uint16_t *)p; mv = *(const int16_t *)p; break; case CTLTYPE_S32: case CTLTYPE_U32: umv = *(const uint32_t *)p; mv = *(const int32_t *)p; break; case CTLTYPE_S64: case CTLTYPE_U64: umv = *(const uint64_t *)p; mv = *(const int64_t *)p; break; } db_printf("%s", sep1); if (xflag) db_printf("%#0*jx", hexlen, umv); else if (!sign) db_printf("%ju", umv); else if (g_ddb_oid->oid_fmt[1] == 'K') { /* Kelvins are currently unsupported. */ error = EOPNOTSUPP; goto out; } else db_printf("%jd", mv); sep1 = " "; len -= intlen; p += intlen; } error = 0; goto out; case CTLTYPE_OPAQUE: /* TODO: Support struct functions. */ /* FALLTHROUGH */ default: db_printf("Format:%s Length:%zu Dump:0x", g_ddb_oid->oid_fmt, len); while (len-- && (xflag || p < val + 16)) db_printf("%02x", *p++); if (!xflag && len > 16) db_printf("..."); error = 0; goto out; } out: req->oldidx += slen; return (error); } /* * Avoid setting new sysctl values from the debugger */ static int sysctl_new_ddb(struct sysctl_req *req, void *p, size_t l) { if (!req->newptr) return (0); /* Changing sysctls from the debugger is currently unsupported */ return (EPERM); } /* * Run a sysctl handler with the DDB oldfunc and newfunc attached. * Instead of copying any output to a buffer we'll dump it right to * the console. */ static int db_sysctl(struct sysctl_oid *oidp, int *name, u_int namelen, void *old, size_t *oldlenp, size_t *retval, int flags) { struct sysctl_req req; int error; /* Setup the request */ bzero(&req, sizeof req); req.td = kdb_thread; req.oldfunc = sysctl_old_ddb; req.newfunc = sysctl_new_ddb; req.lock = REQ_UNWIRED; if (oldlenp) { req.oldlen = *oldlenp; } req.validlen = req.oldlen; if (old) { req.oldptr = old; } /* Setup our globals for sysctl_old_ddb */ g_ddb_oid = oidp; g_ddb_sysctl_flags = flags; g_ddb_sysctl_printed = 0; error = sysctl_root(0, name, namelen, &req); /* Reset globals */ g_ddb_oid = NULL; g_ddb_sysctl_flags = 0; if (retval) { if (req.oldptr && req.oldidx > req.validlen) *retval = req.validlen; else *retval = req.oldidx; } return (error); } /* * Show a sysctl's name */ static void db_show_oid_name(int *oid, size_t nlen) { struct sysctl_oid *oidp; int qoid[CTL_MAXNAME + 2]; int error; qoid[0] = CTL_SYSCTL; qoid[1] = CTL_SYSCTL_NAME; memcpy(qoid + 2, oid, nlen * sizeof(int)); error = sysctl_find_oid(qoid, nlen + 2, &oidp, NULL, NULL); if (error) db_error("sysctl name oid"); error = db_sysctl(oidp, qoid, nlen + 2, NULL, NULL, NULL, 0); if (error) db_error("sysctl name"); } /* * Check to see if an OID is safe to print from ddb. */ static bool db_oid_safe(const struct sysctl_oid *oidp) { for (unsigned int i = 0; i < nitems(db_safe_handlers); ++i) { if (oidp->oid_handler == db_safe_handlers[i]) return (true); } return (false); } /* * Show a sysctl at a specific OID * Compare to the input handling in show_var from sbin/sysctl/sysctl.c */ static int db_show_oid(struct sysctl_oid *oidp, int *oid, size_t nlen, int flags) { int error, xflag, oflag, Nflag, nflag; size_t len; xflag = flags & DB_SYSCTL_HEX; oflag = flags & DB_SYSCTL_OPAQUE; nflag = flags & DB_SYSCTL_VALUE_ONLY; Nflag = flags & DB_SYSCTL_NAME_ONLY; if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_OPAQUE && (!xflag && !oflag)) return (0); if (Nflag) { db_show_oid_name(oid, nlen); error = 0; goto out; } if (!nflag) { db_show_oid_name(oid, nlen); db_printf(": "); } if ((flags & DB_SYSCTL_SAFE_ONLY) && !db_oid_safe(oidp)) { db_printf("Skipping, unsafe to print while recursing."); error = 0; goto out; } /* Try once, and ask about the size */ len = 0; error = db_sysctl(oidp, oid, nlen, NULL, NULL, &len, flags); if (error) goto out; if (!g_ddb_sysctl_printed) /* Lie about the size */ error = db_sysctl(oidp, oid, nlen, (void *) 1, &len, NULL, flags); out: db_printf("\n"); return (error); } /* * Show all sysctls under a specific OID * Compare to sysctl_all from sbin/sysctl/sysctl.c */ static int db_show_sysctl_all(int *oid, size_t len, int flags) { struct sysctl_oid *oidp; int qoid[CTL_MAXNAME + 2], next[CTL_MAXNAME]; size_t nlen; qoid[0] = CTL_SYSCTL; qoid[1] = CTL_SYSCTL_NEXT; if (len) { nlen = len; memcpy(&qoid[2], oid, nlen * sizeof(int)); } else { nlen = 1; qoid[2] = CTL_KERN; } for (;;) { int error; size_t nextsize = sizeof(next); error = kernel_sysctl(kdb_thread, qoid, nlen + 2, next, &nextsize, NULL, 0, &nlen, 0); if (error != 0) { if (error == ENOENT) return (0); else db_error("sysctl(next)"); } nlen /= sizeof(int); if (nlen < (unsigned int)len) return (0); if (memcmp(&oid[0], &next[0], len * sizeof(int)) != 0) return (0); /* Find the OID in question */ error = sysctl_find_oid(next, nlen, &oidp, NULL, NULL); if (error) return (error); (void)db_show_oid(oidp, next, nlen, flags | DB_SYSCTL_SAFE_ONLY); if (db_pager_quit) return (0); memcpy(&qoid[2 + len], &next[len], (nlen - len) * sizeof(int)); } } /* * Show a sysctl by its user facing string */ static int db_sysctlbyname(char *name, int flags) { struct sysctl_oid *oidp; int oid[CTL_MAXNAME]; int error, nlen; error = name2oid(name, oid, &nlen, &oidp); if (error) { return (error); } if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { db_show_sysctl_all(oid, nlen, flags); } else { error = db_show_oid(oidp, oid, nlen, flags); } return (error); } static void db_sysctl_cmd_usage(void) { db_printf( " sysctl [/Nnox] \n" " \n" " The name of the sysctl to show. \n" " \n" " Show a sysctl by hooking into SYSCTL_IN and SYSCTL_OUT. \n" " This will work for most sysctls, but should not be used \n" " with sysctls that are known to malloc. \n" " \n" " While recursing any \"unsafe\" sysctls will be skipped. \n" " Call sysctl directly on the sysctl to try printing the \n" " skipped sysctl. This is unsafe and may make the ddb \n" " session unusable. \n" " \n" " Arguments: \n" " /N Display only the name of the sysctl. \n" " /n Display only the value of the sysctl. \n" " /o Display opaque values. \n" " /x Display the sysctl in hex. \n" " \n" "For example: \n" "sysctl vm.v_free_min \n" "vn.v_free_min: 12669 \n" ); } /* * Show a specific sysctl similar to sysctl (8). */ DB_COMMAND_FLAGS(sysctl, db_sysctl_cmd, CS_OWN) { char name[TOK_STRING_SIZE]; int error, i, t, flags; /* Parse the modifiers */ t = db_read_token(); if (t == tSLASH || t == tMINUS) { t = db_read_token(); if (t != tIDENT) { db_printf("Bad modifier\n"); error = EINVAL; goto out; } db_strcpy(modif, db_tok_string); } else { db_unread_token(t); modif[0] = '\0'; } flags = 0; for (i = 0; i < nitems(db_sysctl_modifs); i++) { if (strchr(modif, db_sysctl_modifs[i])) { flags |= db_sysctl_modif_values[i]; } } /* Parse the sysctl names */ t = db_read_token(); if (t != tIDENT) { db_printf("Need sysctl name\n"); error = EINVAL; goto out; } /* Copy the name into a temporary buffer */ db_strcpy(name, db_tok_string); /* Ensure there is no trailing cruft */ t = db_read_token(); if (t != tEOL) { db_printf("Unexpected sysctl argument\n"); error = EINVAL; goto out; } error = db_sysctlbyname(name, flags); if (error == ENOENT) { db_printf("unknown oid: '%s'\n", db_tok_string); goto out; } else if (error) { db_printf("%s: error: %d\n", db_tok_string, error); goto out; } out: /* Ensure we eat all of our text */ db_flush_lex(); if (error == EINVAL) { db_sysctl_cmd_usage(); } } #endif /* DDB */