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 0x000100 /* 32-bit executable. */ 167 #define SV_LP64 0x000200 /* 64-bit executable. */ 168 #define SV_RESERVED0 0x004000 /* Formerly SV_IA32 */ 169 #define SV_AOUT 0x008000 /* a.out executable. */ 170 #define SV_SHP 0x010000 /* Shared page. */ 171 #define SV_SIGSYS 0x020000 /* SIGSYS for non-existing syscall */ 172 #define SV_TIMEKEEP 0x040000 /* Shared page timehands. */ 173 #define SV_ASLR 0x080000 /* ASLR allowed. */ 174 #define SV_RNG_SEED_VER 0x100000 /* random(4) reseed generation. */ 175 #define SV_SIG_DISCIGN 0x200000 /* Do not discard ignored signals */ 176 #define SV_SIG_WAITNDQ 0x400000 /* Wait does not dequeue SIGCHLD */ 177 #define SV_DSO_SIG 0x800000 /* Signal trampoline packed in dso */ 178 179 #define SV_ABI_MASK 0xff 180 #define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x)) 181 #define SV_PROC_ABI(p) ((p)->p_sysent->sv_flags & SV_ABI_MASK) 182 #define SV_CURPROC_FLAG(x) SV_PROC_FLAG(curproc, x) 183 #define SV_CURPROC_ABI() SV_PROC_ABI(curproc) 184 /* same as ELFOSABI_XXX, to prevent header pollution */ 185 #define SV_ABI_LINUX 3 186 #define SV_ABI_FREEBSD 9 187 #define SV_ABI_UNDEF 255 188 189 /* sv_coredump flags */ 190 #define SVC_PT_COREDUMP 0x00000001 /* dump requested by ptrace(2) */ 191 #define SVC_NOCOMPRESS 0x00000002 /* disable compression. */ 192 #define SVC_ALL 0x00000004 /* dump everything */ 193 194 /* sv_protect flags */ 195 #define SVP_IMAGE 0x00000001 196 #define SVP_INTERP 0x00000002 197 198 #ifdef _KERNEL 199 extern struct sysentvec aout_sysvec; 200 extern struct sysent sysent[]; 201 extern const char *syscallnames[]; 202 extern struct sysent nosys_sysent; 203 204 struct nosys_args { 205 register_t dummy; 206 }; 207 208 int nosys(struct thread *, struct nosys_args *); 209 210 #define NO_SYSCALL (-1) 211 212 struct module; 213 214 struct syscall_module_data { 215 int (*chainevh)(struct module *, int, void *); /* next handler */ 216 void *chainarg; /* arg for next event handler */ 217 int *offset; /* offset into sysent */ 218 struct sysent *new_sysent; /* new sysent */ 219 struct sysent old_sysent; /* old sysent */ 220 int flags; /* flags for syscall_register */ 221 }; 222 223 /* separate initialization vector so it can be used in a substructure */ 224 #define SYSENT_INIT_VALS(_syscallname) { \ 225 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 226 / sizeof(register_t)), \ 227 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 228 .sy_auevent = SYS_AUE_##_syscallname, \ 229 .sy_systrace_args_func = NULL, \ 230 .sy_entry = 0, \ 231 .sy_return = 0, \ 232 .sy_flags = 0, \ 233 .sy_thrcnt = 0 \ 234 } 235 236 #define MAKE_SYSENT(syscallname) \ 237 static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 238 239 #define MAKE_SYSENT_COMPAT(syscallname) \ 240 static struct sysent syscallname##_sysent = { \ 241 (sizeof(struct syscallname ## _args ) \ 242 / sizeof(register_t)), \ 243 (sy_call_t *)& syscallname, \ 244 SYS_AUE_##syscallname \ 245 } 246 247 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 248 static struct syscall_module_data name##_syscall_mod = { \ 249 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 250 }; \ 251 \ 252 static moduledata_t name##_mod = { \ 253 "sys/" #name, \ 254 syscall_module_handler, \ 255 &name##_syscall_mod \ 256 }; \ 257 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 258 259 #define SYSCALL_MODULE_HELPER(syscallname) \ 260 static int syscallname##_syscall = SYS_##syscallname; \ 261 MAKE_SYSENT(syscallname); \ 262 SYSCALL_MODULE(syscallname, \ 263 & syscallname##_syscall, & syscallname##_sysent, \ 264 NULL, NULL) 265 266 #define SYSCALL_MODULE_PRESENT(syscallname) \ 267 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 268 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 269 270 /* 271 * Syscall registration helpers with resource allocation handling. 272 */ 273 struct syscall_helper_data { 274 struct sysent new_sysent; 275 struct sysent old_sysent; 276 int syscall_no; 277 int registered; 278 }; 279 #define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 280 .new_sysent = { \ 281 .sy_narg = (sizeof(struct syscallname ## _args ) \ 282 / sizeof(register_t)), \ 283 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 284 .sy_auevent = SYS_AUE_##syscallname, \ 285 .sy_flags = (flags) \ 286 }, \ 287 .syscall_no = SYS_##syscallname \ 288 } 289 #define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 290 .new_sysent = { \ 291 .sy_narg = (sizeof(struct syscallname ## _args ) \ 292 / sizeof(register_t)), \ 293 .sy_call = (sy_call_t *)& syscallname, \ 294 .sy_auevent = SYS_AUE_##syscallname, \ 295 .sy_flags = (flags) \ 296 }, \ 297 .syscall_no = SYS_##syscallname \ 298 } 299 #define SYSCALL_INIT_HELPER(syscallname) \ 300 SYSCALL_INIT_HELPER_F(syscallname, 0) 301 #define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 302 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 303 #define SYSCALL_INIT_LAST { \ 304 .syscall_no = NO_SYSCALL \ 305 } 306 307 int syscall_module_handler(struct module *mod, int what, void *arg); 308 int syscall_helper_register(struct syscall_helper_data *sd, int flags); 309 int syscall_helper_unregister(struct syscall_helper_data *sd); 310 /* Implementation, exposed for COMPAT code */ 311 int kern_syscall_register(struct sysent *sysents, int *offset, 312 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 313 int kern_syscall_deregister(struct sysent *sysents, int offset, 314 const struct sysent *old_sysent); 315 int kern_syscall_module_handler(struct sysent *sysents, 316 struct module *mod, int what, void *arg); 317 int kern_syscall_helper_register(struct sysent *sysents, 318 struct syscall_helper_data *sd, int flags); 319 int kern_syscall_helper_unregister(struct sysent *sysents, 320 struct syscall_helper_data *sd); 321 322 struct proc; 323 const char *syscallname(struct proc *p, u_int code); 324 325 /* Special purpose system call functions. */ 326 struct nosys_args; 327 328 int lkmnosys(struct thread *, struct nosys_args *); 329 int lkmressys(struct thread *, struct nosys_args *); 330 331 int syscall_thread_enter(struct thread *td, struct sysent **se); 332 void syscall_thread_exit(struct thread *td, struct sysent *se); 333 334 int shared_page_alloc(int size, int align); 335 int shared_page_fill(int size, int align, const void *data); 336 void shared_page_write(int base, int size, const void *data); 337 void exec_sysvec_init(void *param); 338 void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 339 void exec_inittk(void); 340 341 void exit_onexit(struct proc *p); 342 void exec_free_abi_mappings(struct proc *p); 343 void exec_onexec_old(struct thread *td); 344 345 #define INIT_SYSENTVEC(name, sv) \ 346 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \ 347 (sysinit_cfunc_t)exec_sysvec_init, sv); 348 349 #endif /* _KERNEL */ 350 351 #endif /* !_SYS_SYSENT_H_ */ 352