1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1988, 1991 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #ifndef _SYS_SYSENT_H_ 33 #define _SYS_SYSENT_H_ 34 35 #include <bsm/audit.h> 36 37 struct rlimit; 38 struct sysent; 39 struct thread; 40 struct ksiginfo; 41 struct syscall_args; 42 43 enum systrace_probe_t { 44 SYSTRACE_ENTRY, 45 SYSTRACE_RETURN, 46 }; 47 48 typedef int sy_call_t(struct thread *, void *); 49 50 typedef void (*systrace_probe_func_t)(struct syscall_args *, 51 enum systrace_probe_t, int); 52 typedef void (*systrace_args_func_t)(int, void *, uint64_t *, int *); 53 54 #ifdef _KERNEL 55 extern systrace_probe_func_t systrace_probe_func; 56 extern bool systrace_enabled; 57 58 #ifdef KDTRACE_HOOKS 59 #define SYSTRACE_ENABLED() (systrace_enabled) 60 #else 61 #define SYSTRACE_ENABLED() (0) 62 #endif 63 #endif /* _KERNEL */ 64 65 struct sysent { /* system call table */ 66 sy_call_t *sy_call; /* implementing function */ 67 systrace_args_func_t sy_systrace_args_func; 68 /* optional argument conversion function. */ 69 u_int8_t sy_narg; /* number of arguments */ 70 u_int8_t sy_flags; /* General flags for system calls. */ 71 au_event_t sy_auevent; /* audit event associated with syscall */ 72 u_int32_t sy_entry; /* DTrace entry ID for systrace. */ 73 u_int32_t sy_return; /* DTrace return ID for systrace. */ 74 u_int32_t sy_thrcnt; 75 }; 76 77 /* 78 * A system call is permitted in capability mode. 79 */ 80 #define SYF_CAPENABLED 0x00000001 81 82 #define SY_THR_STATIC 0x01 83 #define SY_THR_DRAINING 0x02 84 #define SY_THR_ABSENT 0x04 85 #define SY_THR_INCR 0x08 86 87 #ifdef KLD_MODULE 88 #define SY_THR_STATIC_KLD 0 89 #else 90 #define SY_THR_STATIC_KLD SY_THR_STATIC 91 #endif 92 93 struct coredump_writer; 94 struct image_params; 95 struct proc; 96 struct __sigset; 97 struct trapframe; 98 struct vnode; 99 struct note_info_list; 100 101 struct sysentvec { 102 int sv_size; /* number of entries */ 103 struct sysent *sv_table; /* pointer to sysent */ 104 int (*sv_fixup)(uintptr_t *, struct image_params *); 105 /* stack fixup function */ 106 void (*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *); 107 /* send signal */ 108 const char *sv_sigcode; /* start of sigtramp code */ 109 int *sv_szsigcode; /* size of sigtramp code */ 110 int sv_sigcodeoff; 111 char *sv_name; /* name of binary type */ 112 int (*sv_coredump)(struct thread *, struct coredump_writer *, 113 off_t, int); 114 /* function to dump core, or NULL */ 115 int sv_elf_core_osabi; 116 const char *sv_elf_core_abi_vendor; 117 void (*sv_elf_core_prepare_notes)(struct thread *, 118 struct note_info_list *, size_t *); 119 int (*sv_copyout_auxargs)(struct image_params *, 120 uintptr_t); 121 int sv_minsigstksz; /* minimum signal stack size */ 122 vm_offset_t sv_minuser; /* VM_MIN_ADDRESS */ 123 vm_offset_t sv_maxuser; /* VM_MAXUSER_ADDRESS */ 124 vm_offset_t sv_usrstack; /* USRSTACK */ 125 vm_offset_t sv_psstrings; /* PS_STRINGS */ 126 size_t sv_psstringssz; /* PS_STRINGS size */ 127 int sv_stackprot; /* vm protection for stack */ 128 int (*sv_copyout_strings)(struct image_params *, 129 uintptr_t *); 130 void (*sv_setregs)(struct thread *, struct image_params *, 131 uintptr_t); 132 void (*sv_fixlimit)(struct rlimit *, int); 133 u_long *sv_maxssiz; 134 u_int sv_flags; 135 void (*sv_set_syscall_retval)(struct thread *, int); 136 int (*sv_fetch_syscall_args)(struct thread *); 137 const char **sv_syscallnames; 138 vm_offset_t sv_timekeep_offset; 139 vm_offset_t sv_shared_page_base; 140 vm_offset_t sv_shared_page_len; 141 vm_offset_t sv_sigcode_offset; 142 void *sv_shared_page_obj; 143 vm_offset_t sv_vdso_offset; 144 void (*sv_schedtail)(struct thread *); 145 void (*sv_thread_detach)(struct thread *); 146 int (*sv_trap)(struct thread *); 147 u_long *sv_hwcap; /* Value passed in AT_HWCAP. */ 148 u_long *sv_hwcap2; /* Value passed in AT_HWCAP2. */ 149 u_long *sv_hwcap3; /* Value passed in AT_HWCAP3. */ 150 u_long *sv_hwcap4; /* Value passed in AT_HWCAP4. */ 151 const char *(*sv_machine_arch)(struct proc *); 152 vm_offset_t sv_fxrng_gen_offset; 153 void (*sv_onexec_old)(struct thread *td); 154 int (*sv_onexec)(struct proc *, struct image_params *); 155 void (*sv_protect)(struct image_params *, int); 156 void (*sv_onexit)(struct proc *); 157 void (*sv_ontdexit)(struct thread *td); 158 int (*sv_setid_allowed)(struct thread *td, 159 struct image_params *imgp); 160 void (*sv_set_fork_retval)(struct thread *); 161 /* Only used on x86 */ 162 struct regset **sv_regset_begin; 163 struct regset **sv_regset_end; 164 }; 165 166 #define SV_ILP32 0x00000100 /* 32-bit executable. */ 167 #define SV_LP64 0x00000200 /* 64-bit executable. */ 168 #define SV_RESERVED0 0x00004000 /* Formerly SV_IA32 */ 169 #define SV_AOUT 0x00008000 /* a.out executable. */ 170 #define SV_SHP 0x00010000 /* Shared page. */ 171 #define SV_SIGSYS 0x00020000 /* SIGSYS for non-existing syscall */ 172 #define SV_TIMEKEEP 0x00040000 /* Shared page timehands. */ 173 #define SV_ASLR 0x00080000 /* ASLR allowed. */ 174 #define SV_RNG_SEED_VER 0x00100000 /* random(4) reseed generation. */ 175 #define SV_SIG_DISCIGN 0x00200000 /* Do not discard ignored signals */ 176 #define SV_SIG_WAITNDQ 0x00400000 /* Wait does not dequeue SIGCHLD */ 177 #define SV_DSO_SIG 0x00800000 /* Signal trampoline packed in dso */ 178 #define SV_PERSISTENT_CTTY 0x01000000 /* Keep ctty after the last close */ 179 180 #define SV_ABI_MASK 0xff 181 #define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x)) 182 #define SV_PROC_ABI(p) ((p)->p_sysent->sv_flags & SV_ABI_MASK) 183 #define SV_CURPROC_FLAG(x) SV_PROC_FLAG(curproc, x) 184 #define SV_CURPROC_ABI() SV_PROC_ABI(curproc) 185 /* same as ELFOSABI_XXX, to prevent header pollution */ 186 #define SV_ABI_LINUX 3 187 #define SV_ABI_FREEBSD 9 188 #define SV_ABI_UNDEF 255 189 190 #define SV_ABI_FREEBSD_FLAGS (SV_ABI_FREEBSD | SV_ASLR | SV_SHP | \ 191 SV_TIMEKEEP | SV_RNG_SEED_VER | SV_SIGSYS) 192 #define SV_ABI_LINUX_FLAGS (SV_ABI_LINUX | SV_SHP | SV_SIG_DISCIGN | \ 193 SV_SIG_WAITNDQ | SV_TIMEKEEP | SV_PERSISTENT_CTTY) 194 195 /* sv_coredump flags */ 196 #define SVC_PT_COREDUMP 0x00000001 /* dump requested by ptrace(2) */ 197 #define SVC_NOCOMPRESS 0x00000002 /* disable compression. */ 198 #define SVC_ALL 0x00000004 /* dump everything */ 199 200 /* sv_protect flags */ 201 #define SVP_IMAGE 0x00000001 202 #define SVP_INTERP 0x00000002 203 204 #ifdef _KERNEL 205 extern struct sysentvec aout_sysvec; 206 extern struct sysent sysent[]; 207 extern const char *syscallnames[]; 208 extern struct sysent nosys_sysent; 209 210 struct nosys_args { 211 register_t dummy; 212 }; 213 214 int nosys(struct thread *, struct nosys_args *); 215 216 #define NO_SYSCALL (-1) 217 218 struct module; 219 220 struct syscall_module_data { 221 int (*chainevh)(struct module *, int, void *); /* next handler */ 222 void *chainarg; /* arg for next event handler */ 223 int *offset; /* offset into sysent */ 224 struct sysent *new_sysent; /* new sysent */ 225 struct sysent old_sysent; /* old sysent */ 226 int flags; /* flags for syscall_register */ 227 }; 228 229 /* separate initialization vector so it can be used in a substructure */ 230 #define SYSENT_INIT_VALS(_syscallname) { \ 231 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 232 / sizeof(register_t)), \ 233 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 234 .sy_auevent = SYS_AUE_##_syscallname, \ 235 .sy_systrace_args_func = NULL, \ 236 .sy_entry = 0, \ 237 .sy_return = 0, \ 238 .sy_flags = 0, \ 239 .sy_thrcnt = 0 \ 240 } 241 242 #define MAKE_SYSENT(syscallname) \ 243 static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 244 245 #define MAKE_SYSENT_COMPAT(syscallname) \ 246 static struct sysent syscallname##_sysent = { \ 247 (sizeof(struct syscallname ## _args ) \ 248 / sizeof(register_t)), \ 249 (sy_call_t *)& syscallname, \ 250 SYS_AUE_##syscallname \ 251 } 252 253 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 254 static struct syscall_module_data name##_syscall_mod = { \ 255 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 256 }; \ 257 \ 258 static moduledata_t name##_mod = { \ 259 "sys/" #name, \ 260 syscall_module_handler, \ 261 &name##_syscall_mod \ 262 }; \ 263 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 264 265 #define SYSCALL_MODULE_HELPER(syscallname) \ 266 static int syscallname##_syscall = SYS_##syscallname; \ 267 MAKE_SYSENT(syscallname); \ 268 SYSCALL_MODULE(syscallname, \ 269 & syscallname##_syscall, & syscallname##_sysent, \ 270 NULL, NULL) 271 272 #define SYSCALL_MODULE_PRESENT(syscallname) \ 273 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 274 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 275 276 /* 277 * Syscall registration helpers with resource allocation handling. 278 */ 279 struct syscall_helper_data { 280 struct sysent new_sysent; 281 struct sysent old_sysent; 282 int syscall_no; 283 int registered; 284 }; 285 #define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 286 .new_sysent = { \ 287 .sy_narg = (sizeof(struct syscallname ## _args ) \ 288 / sizeof(register_t)), \ 289 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 290 .sy_auevent = SYS_AUE_##syscallname, \ 291 .sy_flags = (flags) \ 292 }, \ 293 .syscall_no = SYS_##syscallname \ 294 } 295 #define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 296 .new_sysent = { \ 297 .sy_narg = (sizeof(struct syscallname ## _args ) \ 298 / sizeof(register_t)), \ 299 .sy_call = (sy_call_t *)& syscallname, \ 300 .sy_auevent = SYS_AUE_##syscallname, \ 301 .sy_flags = (flags) \ 302 }, \ 303 .syscall_no = SYS_##syscallname \ 304 } 305 #define SYSCALL_INIT_HELPER(syscallname) \ 306 SYSCALL_INIT_HELPER_F(syscallname, 0) 307 #define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 308 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 309 #define SYSCALL_INIT_LAST { \ 310 .syscall_no = NO_SYSCALL \ 311 } 312 313 int syscall_module_handler(struct module *mod, int what, void *arg); 314 int syscall_helper_register(struct syscall_helper_data *sd, int flags); 315 int syscall_helper_unregister(struct syscall_helper_data *sd); 316 /* Implementation, exposed for COMPAT code */ 317 int kern_syscall_register(struct sysent *sysents, int *offset, 318 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 319 int kern_syscall_deregister(struct sysent *sysents, int offset, 320 const struct sysent *old_sysent); 321 int kern_syscall_module_handler(struct sysent *sysents, 322 struct module *mod, int what, void *arg); 323 int kern_syscall_helper_register(struct sysent *sysents, 324 struct syscall_helper_data *sd, int flags); 325 int kern_syscall_helper_unregister(struct sysent *sysents, 326 struct syscall_helper_data *sd); 327 328 struct proc; 329 const char *syscallname(struct proc *p, u_int code); 330 331 /* Special purpose system call functions. */ 332 struct nosys_args; 333 334 int lkmnosys(struct thread *, struct nosys_args *); 335 int lkmressys(struct thread *, struct nosys_args *); 336 337 void syscall_thread_enter(struct thread *td, struct sysent **se); 338 void syscall_thread_exit(struct thread *td, struct sysent *se); 339 340 int shared_page_alloc(int size, int align); 341 int shared_page_fill(int size, int align, const void *data); 342 void shared_page_write(int base, int size, const void *data); 343 void exec_sysvec_init(void *param); 344 void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 345 void exec_inittk(void); 346 347 void exit_onexit(struct proc *p); 348 void exec_free_abi_mappings(struct proc *p); 349 void exec_onexec_old(struct thread *td); 350 351 #define INIT_SYSENTVEC(name, sv) \ 352 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, exec_sysvec_init, sv) 353 354 #endif /* _KERNEL */ 355 356 #endif /* !_SYS_SYSENT_H_ */ 357