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 * $FreeBSD$ 32 */ 33 34 #ifndef _SYS_SYSENT_H_ 35 #define _SYS_SYSENT_H_ 36 37 #include <bsm/audit.h> 38 39 struct rlimit; 40 struct sysent; 41 struct thread; 42 struct ksiginfo; 43 struct syscall_args; 44 45 enum systrace_probe_t { 46 SYSTRACE_ENTRY, 47 SYSTRACE_RETURN, 48 }; 49 50 typedef int sy_call_t(struct thread *, void *); 51 52 typedef void (*systrace_probe_func_t)(struct syscall_args *, 53 enum systrace_probe_t, int); 54 typedef void (*systrace_args_func_t)(int, void *, uint64_t *, int *); 55 56 #ifdef _KERNEL 57 extern systrace_probe_func_t systrace_probe_func; 58 extern bool systrace_enabled; 59 60 #ifdef KDTRACE_HOOKS 61 #define SYSTRACE_ENABLED() (systrace_enabled) 62 #else 63 #define SYSTRACE_ENABLED() (0) 64 #endif 65 #endif /* _KERNEL */ 66 67 struct sysent { /* system call table */ 68 sy_call_t *sy_call; /* implementing function */ 69 systrace_args_func_t sy_systrace_args_func; 70 /* optional argument conversion function. */ 71 u_int8_t sy_narg; /* number of arguments */ 72 u_int8_t sy_flags; /* General flags for system calls. */ 73 au_event_t sy_auevent; /* audit event associated with syscall */ 74 u_int32_t sy_entry; /* DTrace entry ID for systrace. */ 75 u_int32_t sy_return; /* DTrace return ID for systrace. */ 76 u_int32_t sy_thrcnt; 77 }; 78 79 /* 80 * A system call is permitted in capability mode. 81 */ 82 #define SYF_CAPENABLED 0x00000001 83 84 #define SY_THR_FLAGMASK 0x7 85 #define SY_THR_STATIC 0x1 86 #define SY_THR_DRAINING 0x2 87 #define SY_THR_ABSENT 0x4 88 #define SY_THR_INCR 0x8 89 90 #ifdef KLD_MODULE 91 #define SY_THR_STATIC_KLD 0 92 #else 93 #define SY_THR_STATIC_KLD SY_THR_STATIC 94 #endif 95 96 struct image_params; 97 struct proc; 98 struct __sigset; 99 struct trapframe; 100 struct vnode; 101 struct note_info_list; 102 103 struct sysentvec { 104 int sv_size; /* number of entries */ 105 struct sysent *sv_table; /* pointer to sysent */ 106 int (*sv_fixup)(uintptr_t *, struct image_params *); 107 /* stack fixup function */ 108 void (*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *); 109 /* send signal */ 110 const char *sv_sigcode; /* start of sigtramp code */ 111 int *sv_szsigcode; /* size of sigtramp code */ 112 int sv_sigcodeoff; 113 char *sv_name; /* name of binary type */ 114 int (*sv_coredump)(struct thread *, struct vnode *, off_t, int); 115 /* function to dump core, or NULL */ 116 int sv_elf_core_osabi; 117 const char *sv_elf_core_abi_vendor; 118 void (*sv_elf_core_prepare_notes)(struct thread *, 119 struct note_info_list *, size_t *); 120 int (*sv_copyout_auxargs)(struct image_params *, 121 uintptr_t); 122 int sv_minsigstksz; /* minimum signal stack size */ 123 vm_offset_t sv_minuser; /* VM_MIN_ADDRESS */ 124 vm_offset_t sv_maxuser; /* VM_MAXUSER_ADDRESS */ 125 vm_offset_t sv_usrstack; /* USRSTACK */ 126 vm_offset_t sv_psstrings; /* PS_STRINGS */ 127 size_t sv_psstringssz; /* PS_STRINGS size */ 128 int sv_stackprot; /* vm protection for stack */ 129 int (*sv_copyout_strings)(struct image_params *, 130 uintptr_t *); 131 void (*sv_setregs)(struct thread *, struct image_params *, 132 uintptr_t); 133 void (*sv_fixlimit)(struct rlimit *, int); 134 u_long *sv_maxssiz; 135 u_int sv_flags; 136 void (*sv_set_syscall_retval)(struct thread *, int); 137 int (*sv_fetch_syscall_args)(struct thread *); 138 const char **sv_syscallnames; 139 vm_offset_t sv_timekeep_offset; 140 vm_offset_t sv_shared_page_base; 141 vm_offset_t sv_shared_page_len; 142 vm_offset_t sv_sigcode_offset; 143 void *sv_shared_page_obj; 144 vm_offset_t sv_vdso_offset; 145 void (*sv_schedtail)(struct thread *); 146 void (*sv_thread_detach)(struct thread *); 147 int (*sv_trap)(struct thread *); 148 u_long *sv_hwcap; /* Value passed in AT_HWCAP. */ 149 u_long *sv_hwcap2; /* Value passed in AT_HWCAP2. */ 150 const char *(*sv_machine_arch)(struct proc *); 151 vm_offset_t sv_fxrng_gen_offset; 152 void (*sv_onexec_old)(struct thread *td); 153 int (*sv_onexec)(struct proc *, struct image_params *); 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_IA32 0x004000 /* Intel 32-bit executable. */ 167 #define SV_AOUT 0x008000 /* a.out executable. */ 168 #define SV_SHP 0x010000 /* Shared page. */ 169 #define SV_AVAIL1 0x020000 /* Unused */ 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 #ifdef _KERNEL 193 extern struct sysentvec aout_sysvec; 194 extern struct sysent sysent[]; 195 extern const char *syscallnames[]; 196 197 struct nosys_args { 198 register_t dummy; 199 }; 200 201 int nosys(struct thread *, struct nosys_args *); 202 203 #define NO_SYSCALL (-1) 204 205 struct module; 206 207 struct syscall_module_data { 208 int (*chainevh)(struct module *, int, void *); /* next handler */ 209 void *chainarg; /* arg for next event handler */ 210 int *offset; /* offset into sysent */ 211 struct sysent *new_sysent; /* new sysent */ 212 struct sysent old_sysent; /* old sysent */ 213 int flags; /* flags for syscall_register */ 214 }; 215 216 /* separate initialization vector so it can be used in a substructure */ 217 #define SYSENT_INIT_VALS(_syscallname) { \ 218 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 219 / sizeof(register_t)), \ 220 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 221 .sy_auevent = SYS_AUE_##_syscallname, \ 222 .sy_systrace_args_func = NULL, \ 223 .sy_entry = 0, \ 224 .sy_return = 0, \ 225 .sy_flags = 0, \ 226 .sy_thrcnt = 0 \ 227 } 228 229 #define MAKE_SYSENT(syscallname) \ 230 static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 231 232 #define MAKE_SYSENT_COMPAT(syscallname) \ 233 static struct sysent syscallname##_sysent = { \ 234 (sizeof(struct syscallname ## _args ) \ 235 / sizeof(register_t)), \ 236 (sy_call_t *)& syscallname, \ 237 SYS_AUE_##syscallname \ 238 } 239 240 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 241 static struct syscall_module_data name##_syscall_mod = { \ 242 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 243 }; \ 244 \ 245 static moduledata_t name##_mod = { \ 246 "sys/" #name, \ 247 syscall_module_handler, \ 248 &name##_syscall_mod \ 249 }; \ 250 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 251 252 #define SYSCALL_MODULE_HELPER(syscallname) \ 253 static int syscallname##_syscall = SYS_##syscallname; \ 254 MAKE_SYSENT(syscallname); \ 255 SYSCALL_MODULE(syscallname, \ 256 & syscallname##_syscall, & syscallname##_sysent, \ 257 NULL, NULL) 258 259 #define SYSCALL_MODULE_PRESENT(syscallname) \ 260 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 261 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 262 263 /* 264 * Syscall registration helpers with resource allocation handling. 265 */ 266 struct syscall_helper_data { 267 struct sysent new_sysent; 268 struct sysent old_sysent; 269 int syscall_no; 270 int registered; 271 }; 272 #define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 273 .new_sysent = { \ 274 .sy_narg = (sizeof(struct syscallname ## _args ) \ 275 / sizeof(register_t)), \ 276 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 277 .sy_auevent = SYS_AUE_##syscallname, \ 278 .sy_flags = (flags) \ 279 }, \ 280 .syscall_no = SYS_##syscallname \ 281 } 282 #define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 283 .new_sysent = { \ 284 .sy_narg = (sizeof(struct syscallname ## _args ) \ 285 / sizeof(register_t)), \ 286 .sy_call = (sy_call_t *)& syscallname, \ 287 .sy_auevent = SYS_AUE_##syscallname, \ 288 .sy_flags = (flags) \ 289 }, \ 290 .syscall_no = SYS_##syscallname \ 291 } 292 #define SYSCALL_INIT_HELPER(syscallname) \ 293 SYSCALL_INIT_HELPER_F(syscallname, 0) 294 #define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 295 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 296 #define SYSCALL_INIT_LAST { \ 297 .syscall_no = NO_SYSCALL \ 298 } 299 300 int syscall_module_handler(struct module *mod, int what, void *arg); 301 int syscall_helper_register(struct syscall_helper_data *sd, int flags); 302 int syscall_helper_unregister(struct syscall_helper_data *sd); 303 /* Implementation, exposed for COMPAT code */ 304 int kern_syscall_register(struct sysent *sysents, int *offset, 305 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 306 int kern_syscall_deregister(struct sysent *sysents, int offset, 307 const struct sysent *old_sysent); 308 int kern_syscall_module_handler(struct sysent *sysents, 309 struct module *mod, int what, void *arg); 310 int kern_syscall_helper_register(struct sysent *sysents, 311 struct syscall_helper_data *sd, int flags); 312 int kern_syscall_helper_unregister(struct sysent *sysents, 313 struct syscall_helper_data *sd); 314 315 struct proc; 316 const char *syscallname(struct proc *p, u_int code); 317 318 /* Special purpose system call functions. */ 319 struct nosys_args; 320 321 int lkmnosys(struct thread *, struct nosys_args *); 322 int lkmressys(struct thread *, struct nosys_args *); 323 324 int syscall_thread_enter(struct thread *td, struct sysent *se); 325 void syscall_thread_exit(struct thread *td, struct sysent *se); 326 327 int shared_page_alloc(int size, int align); 328 int shared_page_fill(int size, int align, const void *data); 329 void shared_page_write(int base, int size, const void *data); 330 void exec_sysvec_init(void *param); 331 void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 332 void exec_inittk(void); 333 334 void exit_onexit(struct proc *p); 335 void exec_free_abi_mappings(struct proc *p); 336 void exec_onexec_old(struct thread *td); 337 338 #define INIT_SYSENTVEC(name, sv) \ 339 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \ 340 (sysinit_cfunc_t)exec_sysvec_init, sv); 341 342 #endif /* _KERNEL */ 343 344 #endif /* !_SYS_SYSENT_H_ */ 345