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_FLAGMASK 0x7 83 #define SY_THR_STATIC 0x1 84 #define SY_THR_DRAINING 0x2 85 #define SY_THR_ABSENT 0x4 86 #define SY_THR_INCR 0x8 87 88 #ifdef KLD_MODULE 89 #define SY_THR_STATIC_KLD 0 90 #else 91 #define SY_THR_STATIC_KLD SY_THR_STATIC 92 #endif 93 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 vnode *, off_t, int); 113 /* function to dump core, or NULL */ 114 int sv_elf_core_osabi; 115 const char *sv_elf_core_abi_vendor; 116 void (*sv_elf_core_prepare_notes)(struct thread *, 117 struct note_info_list *, size_t *); 118 int (*sv_copyout_auxargs)(struct image_params *, 119 uintptr_t); 120 int sv_minsigstksz; /* minimum signal stack size */ 121 vm_offset_t sv_minuser; /* VM_MIN_ADDRESS */ 122 vm_offset_t sv_maxuser; /* VM_MAXUSER_ADDRESS */ 123 vm_offset_t sv_usrstack; /* USRSTACK */ 124 vm_offset_t sv_psstrings; /* PS_STRINGS */ 125 size_t sv_psstringssz; /* PS_STRINGS size */ 126 int sv_stackprot; /* vm protection for stack */ 127 int (*sv_copyout_strings)(struct image_params *, 128 uintptr_t *); 129 void (*sv_setregs)(struct thread *, struct image_params *, 130 uintptr_t); 131 void (*sv_fixlimit)(struct rlimit *, int); 132 u_long *sv_maxssiz; 133 u_int sv_flags; 134 void (*sv_set_syscall_retval)(struct thread *, int); 135 int (*sv_fetch_syscall_args)(struct thread *); 136 const char **sv_syscallnames; 137 vm_offset_t sv_timekeep_offset; 138 vm_offset_t sv_shared_page_base; 139 vm_offset_t sv_shared_page_len; 140 vm_offset_t sv_sigcode_offset; 141 void *sv_shared_page_obj; 142 vm_offset_t sv_vdso_offset; 143 void (*sv_schedtail)(struct thread *); 144 void (*sv_thread_detach)(struct thread *); 145 int (*sv_trap)(struct thread *); 146 u_long *sv_hwcap; /* Value passed in AT_HWCAP. */ 147 u_long *sv_hwcap2; /* Value passed in AT_HWCAP2. */ 148 const char *(*sv_machine_arch)(struct proc *); 149 vm_offset_t sv_fxrng_gen_offset; 150 void (*sv_onexec_old)(struct thread *td); 151 int (*sv_onexec)(struct proc *, struct image_params *); 152 void (*sv_onexit)(struct proc *); 153 void (*sv_ontdexit)(struct thread *td); 154 int (*sv_setid_allowed)(struct thread *td, 155 struct image_params *imgp); 156 void (*sv_set_fork_retval)(struct thread *); 157 /* Only used on x86 */ 158 struct regset **sv_regset_begin; 159 struct regset **sv_regset_end; 160 }; 161 162 #define SV_ILP32 0x000100 /* 32-bit executable. */ 163 #define SV_LP64 0x000200 /* 64-bit executable. */ 164 #define SV_IA32 0x004000 /* Intel 32-bit executable. */ 165 #define SV_AOUT 0x008000 /* a.out executable. */ 166 #define SV_SHP 0x010000 /* Shared page. */ 167 #define SV_SIGSYS 0x020000 /* SIGSYS for non-existing syscall */ 168 #define SV_TIMEKEEP 0x040000 /* Shared page timehands. */ 169 #define SV_ASLR 0x080000 /* ASLR allowed. */ 170 #define SV_RNG_SEED_VER 0x100000 /* random(4) reseed generation. */ 171 #define SV_SIG_DISCIGN 0x200000 /* Do not discard ignored signals */ 172 #define SV_SIG_WAITNDQ 0x400000 /* Wait does not dequeue SIGCHLD */ 173 #define SV_DSO_SIG 0x800000 /* Signal trampoline packed in dso */ 174 175 #define SV_ABI_MASK 0xff 176 #define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x)) 177 #define SV_PROC_ABI(p) ((p)->p_sysent->sv_flags & SV_ABI_MASK) 178 #define SV_CURPROC_FLAG(x) SV_PROC_FLAG(curproc, x) 179 #define SV_CURPROC_ABI() SV_PROC_ABI(curproc) 180 /* same as ELFOSABI_XXX, to prevent header pollution */ 181 #define SV_ABI_LINUX 3 182 #define SV_ABI_FREEBSD 9 183 #define SV_ABI_UNDEF 255 184 185 /* sv_coredump flags */ 186 #define SVC_PT_COREDUMP 0x00000001 /* dump requested by ptrace(2) */ 187 #define SVC_NOCOMPRESS 0x00000002 /* disable compression. */ 188 #define SVC_ALL 0x00000004 /* dump everything */ 189 190 #ifdef _KERNEL 191 extern struct sysentvec aout_sysvec; 192 extern struct sysent sysent[]; 193 extern const char *syscallnames[]; 194 extern struct sysent nosys_sysent; 195 196 struct nosys_args { 197 register_t dummy; 198 }; 199 200 int nosys(struct thread *, struct nosys_args *); 201 202 #define NO_SYSCALL (-1) 203 204 struct module; 205 206 struct syscall_module_data { 207 int (*chainevh)(struct module *, int, void *); /* next handler */ 208 void *chainarg; /* arg for next event handler */ 209 int *offset; /* offset into sysent */ 210 struct sysent *new_sysent; /* new sysent */ 211 struct sysent old_sysent; /* old sysent */ 212 int flags; /* flags for syscall_register */ 213 }; 214 215 /* separate initialization vector so it can be used in a substructure */ 216 #define SYSENT_INIT_VALS(_syscallname) { \ 217 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 218 / sizeof(register_t)), \ 219 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 220 .sy_auevent = SYS_AUE_##_syscallname, \ 221 .sy_systrace_args_func = NULL, \ 222 .sy_entry = 0, \ 223 .sy_return = 0, \ 224 .sy_flags = 0, \ 225 .sy_thrcnt = 0 \ 226 } 227 228 #define MAKE_SYSENT(syscallname) \ 229 static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 230 231 #define MAKE_SYSENT_COMPAT(syscallname) \ 232 static struct sysent syscallname##_sysent = { \ 233 (sizeof(struct syscallname ## _args ) \ 234 / sizeof(register_t)), \ 235 (sy_call_t *)& syscallname, \ 236 SYS_AUE_##syscallname \ 237 } 238 239 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 240 static struct syscall_module_data name##_syscall_mod = { \ 241 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 242 }; \ 243 \ 244 static moduledata_t name##_mod = { \ 245 "sys/" #name, \ 246 syscall_module_handler, \ 247 &name##_syscall_mod \ 248 }; \ 249 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 250 251 #define SYSCALL_MODULE_HELPER(syscallname) \ 252 static int syscallname##_syscall = SYS_##syscallname; \ 253 MAKE_SYSENT(syscallname); \ 254 SYSCALL_MODULE(syscallname, \ 255 & syscallname##_syscall, & syscallname##_sysent, \ 256 NULL, NULL) 257 258 #define SYSCALL_MODULE_PRESENT(syscallname) \ 259 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 260 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 261 262 /* 263 * Syscall registration helpers with resource allocation handling. 264 */ 265 struct syscall_helper_data { 266 struct sysent new_sysent; 267 struct sysent old_sysent; 268 int syscall_no; 269 int registered; 270 }; 271 #define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 272 .new_sysent = { \ 273 .sy_narg = (sizeof(struct syscallname ## _args ) \ 274 / sizeof(register_t)), \ 275 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 276 .sy_auevent = SYS_AUE_##syscallname, \ 277 .sy_flags = (flags) \ 278 }, \ 279 .syscall_no = SYS_##syscallname \ 280 } 281 #define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 282 .new_sysent = { \ 283 .sy_narg = (sizeof(struct syscallname ## _args ) \ 284 / sizeof(register_t)), \ 285 .sy_call = (sy_call_t *)& syscallname, \ 286 .sy_auevent = SYS_AUE_##syscallname, \ 287 .sy_flags = (flags) \ 288 }, \ 289 .syscall_no = SYS_##syscallname \ 290 } 291 #define SYSCALL_INIT_HELPER(syscallname) \ 292 SYSCALL_INIT_HELPER_F(syscallname, 0) 293 #define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 294 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 295 #define SYSCALL_INIT_LAST { \ 296 .syscall_no = NO_SYSCALL \ 297 } 298 299 int syscall_module_handler(struct module *mod, int what, void *arg); 300 int syscall_helper_register(struct syscall_helper_data *sd, int flags); 301 int syscall_helper_unregister(struct syscall_helper_data *sd); 302 /* Implementation, exposed for COMPAT code */ 303 int kern_syscall_register(struct sysent *sysents, int *offset, 304 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 305 int kern_syscall_deregister(struct sysent *sysents, int offset, 306 const struct sysent *old_sysent); 307 int kern_syscall_module_handler(struct sysent *sysents, 308 struct module *mod, int what, void *arg); 309 int kern_syscall_helper_register(struct sysent *sysents, 310 struct syscall_helper_data *sd, int flags); 311 int kern_syscall_helper_unregister(struct sysent *sysents, 312 struct syscall_helper_data *sd); 313 314 struct proc; 315 const char *syscallname(struct proc *p, u_int code); 316 317 /* Special purpose system call functions. */ 318 struct nosys_args; 319 320 int lkmnosys(struct thread *, struct nosys_args *); 321 int lkmressys(struct thread *, struct nosys_args *); 322 323 int syscall_thread_enter(struct thread *td, struct sysent **se); 324 void syscall_thread_exit(struct thread *td, struct sysent *se); 325 326 int shared_page_alloc(int size, int align); 327 int shared_page_fill(int size, int align, const void *data); 328 void shared_page_write(int base, int size, const void *data); 329 void exec_sysvec_init(void *param); 330 void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 331 void exec_inittk(void); 332 333 void exit_onexit(struct proc *p); 334 void exec_free_abi_mappings(struct proc *p); 335 void exec_onexec_old(struct thread *td); 336 337 #define INIT_SYSENTVEC(name, sv) \ 338 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \ 339 (sysinit_cfunc_t)exec_sysvec_init, sv); 340 341 #endif /* _KERNEL */ 342 343 #endif /* !_SYS_SYSENT_H_ */ 344