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 image_params; 94 struct proc; 95 struct __sigset; 96 struct trapframe; 97 struct vnode; 98 struct note_info_list; 99 100 struct sysentvec { 101 int sv_size; /* number of entries */ 102 struct sysent *sv_table; /* pointer to sysent */ 103 int (*sv_fixup)(uintptr_t *, struct image_params *); 104 /* stack fixup function */ 105 void (*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *); 106 /* send signal */ 107 const char *sv_sigcode; /* start of sigtramp code */ 108 int *sv_szsigcode; /* size of sigtramp code */ 109 int sv_sigcodeoff; 110 char *sv_name; /* name of binary type */ 111 int (*sv_coredump)(struct thread *, struct vnode *, off_t, int); 112 /* function to dump core, or NULL */ 113 int sv_elf_core_osabi; 114 const char *sv_elf_core_abi_vendor; 115 void (*sv_elf_core_prepare_notes)(struct thread *, 116 struct note_info_list *, size_t *); 117 int (*sv_copyout_auxargs)(struct image_params *, 118 uintptr_t); 119 int sv_minsigstksz; /* minimum signal stack size */ 120 vm_offset_t sv_minuser; /* VM_MIN_ADDRESS */ 121 vm_offset_t sv_maxuser; /* VM_MAXUSER_ADDRESS */ 122 vm_offset_t sv_usrstack; /* USRSTACK */ 123 vm_offset_t sv_psstrings; /* PS_STRINGS */ 124 size_t sv_psstringssz; /* PS_STRINGS size */ 125 int sv_stackprot; /* vm protection for stack */ 126 int (*sv_copyout_strings)(struct image_params *, 127 uintptr_t *); 128 void (*sv_setregs)(struct thread *, struct image_params *, 129 uintptr_t); 130 void (*sv_fixlimit)(struct rlimit *, int); 131 u_long *sv_maxssiz; 132 u_int sv_flags; 133 void (*sv_set_syscall_retval)(struct thread *, int); 134 int (*sv_fetch_syscall_args)(struct thread *); 135 const char **sv_syscallnames; 136 vm_offset_t sv_timekeep_offset; 137 vm_offset_t sv_shared_page_base; 138 vm_offset_t sv_shared_page_len; 139 vm_offset_t sv_sigcode_offset; 140 void *sv_shared_page_obj; 141 vm_offset_t sv_vdso_offset; 142 void (*sv_schedtail)(struct thread *); 143 void (*sv_thread_detach)(struct thread *); 144 int (*sv_trap)(struct thread *); 145 u_long *sv_hwcap; /* Value passed in AT_HWCAP. */ 146 u_long *sv_hwcap2; /* Value passed in AT_HWCAP2. */ 147 u_long *sv_hwcap3; /* Value passed in AT_HWCAP3. */ 148 u_long *sv_hwcap4; /* Value passed in AT_HWCAP4. */ 149 const char *(*sv_machine_arch)(struct proc *); 150 vm_offset_t sv_fxrng_gen_offset; 151 void (*sv_onexec_old)(struct thread *td); 152 int (*sv_onexec)(struct proc *, struct image_params *); 153 void (*sv_protect)(struct image_params *, int); 154 void (*sv_onexit)(struct proc *); 155 void (*sv_ontdexit)(struct thread *td); 156 int (*sv_setid_allowed)(struct thread *td, 157 struct image_params *imgp); 158 void (*sv_set_fork_retval)(struct thread *); 159 /* Only used on x86 */ 160 struct regset **sv_regset_begin; 161 struct regset **sv_regset_end; 162 }; 163 164 #define SV_ILP32 0x000100 /* 32-bit executable. */ 165 #define SV_LP64 0x000200 /* 64-bit executable. */ 166 #define SV_RESERVED0 0x004000 /* Formerly SV_IA32 */ 167 #define SV_AOUT 0x008000 /* a.out executable. */ 168 #define SV_SHP 0x010000 /* Shared page. */ 169 #define SV_SIGSYS 0x020000 /* SIGSYS for non-existing syscall */ 170 #define SV_TIMEKEEP 0x040000 /* Shared page timehands. */ 171 #define SV_ASLR 0x080000 /* ASLR allowed. */ 172 #define SV_RNG_SEED_VER 0x100000 /* random(4) reseed generation. */ 173 #define SV_SIG_DISCIGN 0x200000 /* Do not discard ignored signals */ 174 #define SV_SIG_WAITNDQ 0x400000 /* Wait does not dequeue SIGCHLD */ 175 #define SV_DSO_SIG 0x800000 /* Signal trampoline packed in dso */ 176 177 #define SV_ABI_MASK 0xff 178 #define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x)) 179 #define SV_PROC_ABI(p) ((p)->p_sysent->sv_flags & SV_ABI_MASK) 180 #define SV_CURPROC_FLAG(x) SV_PROC_FLAG(curproc, x) 181 #define SV_CURPROC_ABI() SV_PROC_ABI(curproc) 182 /* same as ELFOSABI_XXX, to prevent header pollution */ 183 #define SV_ABI_LINUX 3 184 #define SV_ABI_FREEBSD 9 185 #define SV_ABI_UNDEF 255 186 187 /* sv_coredump flags */ 188 #define SVC_PT_COREDUMP 0x00000001 /* dump requested by ptrace(2) */ 189 #define SVC_NOCOMPRESS 0x00000002 /* disable compression. */ 190 #define SVC_ALL 0x00000004 /* dump everything */ 191 192 /* sv_protect flags */ 193 #define SVP_IMAGE 0x00000001 194 #define SVP_INTERP 0x00000002 195 196 #ifdef _KERNEL 197 extern struct sysentvec aout_sysvec; 198 extern struct sysent sysent[]; 199 extern const char *syscallnames[]; 200 extern struct sysent nosys_sysent; 201 202 struct nosys_args { 203 register_t dummy; 204 }; 205 206 int nosys(struct thread *, struct nosys_args *); 207 208 #define NO_SYSCALL (-1) 209 210 struct module; 211 212 struct syscall_module_data { 213 int (*chainevh)(struct module *, int, void *); /* next handler */ 214 void *chainarg; /* arg for next event handler */ 215 int *offset; /* offset into sysent */ 216 struct sysent *new_sysent; /* new sysent */ 217 struct sysent old_sysent; /* old sysent */ 218 int flags; /* flags for syscall_register */ 219 }; 220 221 /* separate initialization vector so it can be used in a substructure */ 222 #define SYSENT_INIT_VALS(_syscallname) { \ 223 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 224 / sizeof(register_t)), \ 225 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 226 .sy_auevent = SYS_AUE_##_syscallname, \ 227 .sy_systrace_args_func = NULL, \ 228 .sy_entry = 0, \ 229 .sy_return = 0, \ 230 .sy_flags = 0, \ 231 .sy_thrcnt = 0 \ 232 } 233 234 #define MAKE_SYSENT(syscallname) \ 235 static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 236 237 #define MAKE_SYSENT_COMPAT(syscallname) \ 238 static struct sysent syscallname##_sysent = { \ 239 (sizeof(struct syscallname ## _args ) \ 240 / sizeof(register_t)), \ 241 (sy_call_t *)& syscallname, \ 242 SYS_AUE_##syscallname \ 243 } 244 245 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 246 static struct syscall_module_data name##_syscall_mod = { \ 247 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 248 }; \ 249 \ 250 static moduledata_t name##_mod = { \ 251 "sys/" #name, \ 252 syscall_module_handler, \ 253 &name##_syscall_mod \ 254 }; \ 255 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 256 257 #define SYSCALL_MODULE_HELPER(syscallname) \ 258 static int syscallname##_syscall = SYS_##syscallname; \ 259 MAKE_SYSENT(syscallname); \ 260 SYSCALL_MODULE(syscallname, \ 261 & syscallname##_syscall, & syscallname##_sysent, \ 262 NULL, NULL) 263 264 #define SYSCALL_MODULE_PRESENT(syscallname) \ 265 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 266 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 267 268 /* 269 * Syscall registration helpers with resource allocation handling. 270 */ 271 struct syscall_helper_data { 272 struct sysent new_sysent; 273 struct sysent old_sysent; 274 int syscall_no; 275 int registered; 276 }; 277 #define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 278 .new_sysent = { \ 279 .sy_narg = (sizeof(struct syscallname ## _args ) \ 280 / sizeof(register_t)), \ 281 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 282 .sy_auevent = SYS_AUE_##syscallname, \ 283 .sy_flags = (flags) \ 284 }, \ 285 .syscall_no = SYS_##syscallname \ 286 } 287 #define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 288 .new_sysent = { \ 289 .sy_narg = (sizeof(struct syscallname ## _args ) \ 290 / sizeof(register_t)), \ 291 .sy_call = (sy_call_t *)& syscallname, \ 292 .sy_auevent = SYS_AUE_##syscallname, \ 293 .sy_flags = (flags) \ 294 }, \ 295 .syscall_no = SYS_##syscallname \ 296 } 297 #define SYSCALL_INIT_HELPER(syscallname) \ 298 SYSCALL_INIT_HELPER_F(syscallname, 0) 299 #define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 300 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 301 #define SYSCALL_INIT_LAST { \ 302 .syscall_no = NO_SYSCALL \ 303 } 304 305 int syscall_module_handler(struct module *mod, int what, void *arg); 306 int syscall_helper_register(struct syscall_helper_data *sd, int flags); 307 int syscall_helper_unregister(struct syscall_helper_data *sd); 308 /* Implementation, exposed for COMPAT code */ 309 int kern_syscall_register(struct sysent *sysents, int *offset, 310 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 311 int kern_syscall_deregister(struct sysent *sysents, int offset, 312 const struct sysent *old_sysent); 313 int kern_syscall_module_handler(struct sysent *sysents, 314 struct module *mod, int what, void *arg); 315 int kern_syscall_helper_register(struct sysent *sysents, 316 struct syscall_helper_data *sd, int flags); 317 int kern_syscall_helper_unregister(struct sysent *sysents, 318 struct syscall_helper_data *sd); 319 320 struct proc; 321 const char *syscallname(struct proc *p, u_int code); 322 323 /* Special purpose system call functions. */ 324 struct nosys_args; 325 326 int lkmnosys(struct thread *, struct nosys_args *); 327 int lkmressys(struct thread *, struct nosys_args *); 328 329 int syscall_thread_enter(struct thread *td, struct sysent **se); 330 void syscall_thread_exit(struct thread *td, struct sysent *se); 331 332 int shared_page_alloc(int size, int align); 333 int shared_page_fill(int size, int align, const void *data); 334 void shared_page_write(int base, int size, const void *data); 335 void exec_sysvec_init(void *param); 336 void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 337 void exec_inittk(void); 338 339 void exit_onexit(struct proc *p); 340 void exec_free_abi_mappings(struct proc *p); 341 void exec_onexec_old(struct thread *td); 342 343 #define INIT_SYSENTVEC(name, sv) \ 344 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \ 345 (sysinit_cfunc_t)exec_sysvec_init, sv); 346 347 #endif /* _KERNEL */ 348 349 #endif /* !_SYS_SYSENT_H_ */ 350