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 37struct rlimit; 38struct sysent; 39struct thread; 40struct ksiginfo; 41struct syscall_args; 42 43enum systrace_probe_t { 44 SYSTRACE_ENTRY, 45 SYSTRACE_RETURN, 46}; 47 48typedef int sy_call_t(struct thread *, void *); 49 50typedef void (*systrace_probe_func_t)(struct syscall_args *, 51 enum systrace_probe_t, int); 52typedef void (*systrace_args_func_t)(int, void *, uint64_t *, int *); 53 54#ifdef _KERNEL 55extern systrace_probe_func_t systrace_probe_func; 56extern 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 65struct 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 94struct image_params; 95struct proc; 96struct __sigset; 97struct trapframe; 98struct vnode; 99struct note_info_list; 100 101struct 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_protect)(struct image_params *, int); 153 void (*sv_onexit)(struct proc *); 154 void (*sv_ontdexit)(struct thread *td); 155 int (*sv_setid_allowed)(struct thread *td, 156 struct image_params *imgp); 157 void (*sv_set_fork_retval)(struct thread *); 158 /* Only used on x86 */ 159 struct regset **sv_regset_begin; 160 struct regset **sv_regset_end; 161}; 162 163#define SV_ILP32 0x000100 /* 32-bit executable. */ 164#define SV_LP64 0x000200 /* 64-bit executable. */ 165#define SV_IA32 0x004000 /* Intel 32-bit executable. */ 166#define SV_AOUT 0x008000 /* a.out executable. */ 167#define SV_SHP 0x010000 /* Shared page. */ 168#define SV_SIGSYS 0x020000 /* SIGSYS for non-existing syscall */ 169#define SV_TIMEKEEP 0x040000 /* Shared page timehands. */ 170#define SV_ASLR 0x080000 /* ASLR allowed. */ 171#define SV_RNG_SEED_VER 0x100000 /* random(4) reseed generation. */ 172#define SV_SIG_DISCIGN 0x200000 /* Do not discard ignored signals */ 173#define SV_SIG_WAITNDQ 0x400000 /* Wait does not dequeue SIGCHLD */ 174#define SV_DSO_SIG 0x800000 /* Signal trampoline packed in dso */ 175 176#define SV_ABI_MASK 0xff 177#define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x)) 178#define SV_PROC_ABI(p) ((p)->p_sysent->sv_flags & SV_ABI_MASK) 179#define SV_CURPROC_FLAG(x) SV_PROC_FLAG(curproc, x) 180#define SV_CURPROC_ABI() SV_PROC_ABI(curproc) 181/* same as ELFOSABI_XXX, to prevent header pollution */ 182#define SV_ABI_LINUX 3 183#define SV_ABI_FREEBSD 9 184#define SV_ABI_UNDEF 255 185 186/* sv_coredump flags */ 187#define SVC_PT_COREDUMP 0x00000001 /* dump requested by ptrace(2) */ 188#define SVC_NOCOMPRESS 0x00000002 /* disable compression. */ 189#define SVC_ALL 0x00000004 /* dump everything */ 190 191/* sv_protect flags */ 192#define SVP_IMAGE 0x00000001 193#define SVP_INTERP 0x00000002 194 195#ifdef _KERNEL 196extern struct sysentvec aout_sysvec; 197extern struct sysent sysent[]; 198extern const char *syscallnames[]; 199extern struct sysent nosys_sysent; 200 201struct nosys_args { 202 register_t dummy; 203}; 204 205int nosys(struct thread *, struct nosys_args *); 206 207#define NO_SYSCALL (-1) 208 209struct module; 210 211struct syscall_module_data { 212 int (*chainevh)(struct module *, int, void *); /* next handler */ 213 void *chainarg; /* arg for next event handler */ 214 int *offset; /* offset into sysent */ 215 struct sysent *new_sysent; /* new sysent */ 216 struct sysent old_sysent; /* old sysent */ 217 int flags; /* flags for syscall_register */ 218}; 219 220/* separate initialization vector so it can be used in a substructure */ 221#define SYSENT_INIT_VALS(_syscallname) { \ 222 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 223 / sizeof(register_t)), \ 224 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 225 .sy_auevent = SYS_AUE_##_syscallname, \ 226 .sy_systrace_args_func = NULL, \ 227 .sy_entry = 0, \ 228 .sy_return = 0, \ 229 .sy_flags = 0, \ 230 .sy_thrcnt = 0 \ 231} 232 233#define MAKE_SYSENT(syscallname) \ 234static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 235 236#define MAKE_SYSENT_COMPAT(syscallname) \ 237static struct sysent syscallname##_sysent = { \ 238 (sizeof(struct syscallname ## _args ) \ 239 / sizeof(register_t)), \ 240 (sy_call_t *)& syscallname, \ 241 SYS_AUE_##syscallname \ 242} 243 244#define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 245static struct syscall_module_data name##_syscall_mod = { \ 246 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 247}; \ 248 \ 249static moduledata_t name##_mod = { \ 250 "sys/" #name, \ 251 syscall_module_handler, \ 252 &name##_syscall_mod \ 253}; \ 254DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 255 256#define SYSCALL_MODULE_HELPER(syscallname) \ 257static int syscallname##_syscall = SYS_##syscallname; \ 258MAKE_SYSENT(syscallname); \ 259SYSCALL_MODULE(syscallname, \ 260 & syscallname##_syscall, & syscallname##_sysent, \ 261 NULL, NULL) 262 263#define SYSCALL_MODULE_PRESENT(syscallname) \ 264 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 265 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 266 267/* 268 * Syscall registration helpers with resource allocation handling. 269 */ 270struct syscall_helper_data { 271 struct sysent new_sysent; 272 struct sysent old_sysent; 273 int syscall_no; 274 int registered; 275}; 276#define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 277 .new_sysent = { \ 278 .sy_narg = (sizeof(struct syscallname ## _args ) \ 279 / sizeof(register_t)), \ 280 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 281 .sy_auevent = SYS_AUE_##syscallname, \ 282 .sy_flags = (flags) \ 283 }, \ 284 .syscall_no = SYS_##syscallname \ 285} 286#define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 287 .new_sysent = { \ 288 .sy_narg = (sizeof(struct syscallname ## _args ) \ 289 / sizeof(register_t)), \ 290 .sy_call = (sy_call_t *)& syscallname, \ 291 .sy_auevent = SYS_AUE_##syscallname, \ 292 .sy_flags = (flags) \ 293 }, \ 294 .syscall_no = SYS_##syscallname \ 295} 296#define SYSCALL_INIT_HELPER(syscallname) \ 297 SYSCALL_INIT_HELPER_F(syscallname, 0) 298#define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 299 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 300#define SYSCALL_INIT_LAST { \ 301 .syscall_no = NO_SYSCALL \ 302} 303 304int syscall_module_handler(struct module *mod, int what, void *arg); 305int syscall_helper_register(struct syscall_helper_data *sd, int flags); 306int syscall_helper_unregister(struct syscall_helper_data *sd); 307/* Implementation, exposed for COMPAT code */ 308int kern_syscall_register(struct sysent *sysents, int *offset, 309 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 310int kern_syscall_deregister(struct sysent *sysents, int offset, 311 const struct sysent *old_sysent); 312int kern_syscall_module_handler(struct sysent *sysents, 313 struct module *mod, int what, void *arg); 314int kern_syscall_helper_register(struct sysent *sysents, 315 struct syscall_helper_data *sd, int flags); 316int kern_syscall_helper_unregister(struct sysent *sysents, 317 struct syscall_helper_data *sd); 318 319struct proc; 320const char *syscallname(struct proc *p, u_int code); 321 322/* Special purpose system call functions. */ 323struct nosys_args; 324 325int lkmnosys(struct thread *, struct nosys_args *); 326int lkmressys(struct thread *, struct nosys_args *); 327 328int syscall_thread_enter(struct thread *td, struct sysent **se); 329void syscall_thread_exit(struct thread *td, struct sysent *se); 330 331int shared_page_alloc(int size, int align); 332int shared_page_fill(int size, int align, const void *data); 333void shared_page_write(int base, int size, const void *data); 334void exec_sysvec_init(void *param); 335void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 336void exec_inittk(void); 337 338void exit_onexit(struct proc *p); 339void exec_free_abi_mappings(struct proc *p); 340void exec_onexec_old(struct thread *td); 341 342#define INIT_SYSENTVEC(name, sv) \ 343 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \ 344 (sysinit_cfunc_t)exec_sysvec_init, sv); 345 346#endif /* _KERNEL */ 347 348#endif /* !_SYS_SYSENT_H_ */ 349