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_transtrap)(int, int); 107 /* translate trap-to-signal mapping */ 108 int (*sv_fixup)(uintptr_t *, struct image_params *); 109 /* stack fixup function */ 110 void (*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *); 111 /* send signal */ 112 char *sv_sigcode; /* start of sigtramp code */ 113 int *sv_szsigcode; /* size of sigtramp code */ 114 char *sv_name; /* name of binary type */ 115 int (*sv_coredump)(struct thread *, struct vnode *, off_t, int); 116 /* function to dump core, or NULL */ 117 int sv_elf_core_osabi; 118 const char *sv_elf_core_abi_vendor; 119 void (*sv_elf_core_prepare_notes)(struct thread *, 120 struct note_info_list *, size_t *); 121 int (*sv_imgact_try)(struct image_params *); 122 vm_size_t (*sv_stackgap)(struct image_params *, uintptr_t *); 123 int (*sv_copyout_auxargs)(struct image_params *, 124 uintptr_t); 125 int sv_minsigstksz; /* minimum signal stack size */ 126 vm_offset_t sv_minuser; /* VM_MIN_ADDRESS */ 127 vm_offset_t sv_maxuser; /* VM_MAXUSER_ADDRESS */ 128 vm_offset_t sv_usrstack; /* USRSTACK */ 129 vm_offset_t sv_psstrings; /* PS_STRINGS */ 130 int sv_stackprot; /* vm protection for stack */ 131 int (*sv_copyout_strings)(struct image_params *, 132 uintptr_t *); 133 void (*sv_setregs)(struct thread *, struct image_params *, 134 uintptr_t); 135 void (*sv_fixlimit)(struct rlimit *, int); 136 u_long *sv_maxssiz; 137 u_int sv_flags; 138 void (*sv_set_syscall_retval)(struct thread *, int); 139 int (*sv_fetch_syscall_args)(struct thread *); 140 const char **sv_syscallnames; 141 vm_offset_t sv_timekeep_base; 142 vm_offset_t sv_shared_page_base; 143 vm_offset_t sv_shared_page_len; 144 vm_offset_t sv_sigcode_base; 145 void *sv_shared_page_obj; 146 void (*sv_schedtail)(struct thread *); 147 void (*sv_thread_detach)(struct thread *); 148 int (*sv_trap)(struct thread *); 149 u_long *sv_hwcap; /* Value passed in AT_HWCAP. */ 150 u_long *sv_hwcap2; /* Value passed in AT_HWCAP2. */ 151 const char *(*sv_machine_arch)(struct proc *); 152 vm_offset_t sv_fxrng_gen_base; 153 void (*sv_onexec_old)(struct thread *td); 154 int (*sv_onexec)(struct proc *, struct image_params *); 155 void (*sv_onexit)(struct proc *); 156 void (*sv_ontdexit)(struct thread *td); 157 int (*sv_setid_allowed)(struct thread *td, 158 struct image_params *imgp); 159 void (*sv_set_fork_retval)(struct thread *); 160 /* Only used on x86 */ 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_AVAIL1 0x020000 /* Unused */ 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 */ 174 175 #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[]; 194 195 #define NO_SYSCALL (-1) 196 197 struct module; 198 199 struct syscall_module_data { 200 int (*chainevh)(struct module *, int, void *); /* next handler */ 201 void *chainarg; /* arg for next event handler */ 202 int *offset; /* offset into sysent */ 203 struct sysent *new_sysent; /* new sysent */ 204 struct sysent old_sysent; /* old sysent */ 205 int flags; /* flags for syscall_register */ 206 }; 207 208 /* separate initialization vector so it can be used in a substructure */ 209 #define SYSENT_INIT_VALS(_syscallname) { \ 210 .sy_narg = (sizeof(struct _syscallname ## _args ) \ 211 / sizeof(register_t)), \ 212 .sy_call = (sy_call_t *)&sys_##_syscallname, \ 213 .sy_auevent = SYS_AUE_##_syscallname, \ 214 .sy_systrace_args_func = NULL, \ 215 .sy_entry = 0, \ 216 .sy_return = 0, \ 217 .sy_flags = 0, \ 218 .sy_thrcnt = 0 \ 219 } 220 221 #define MAKE_SYSENT(syscallname) \ 222 static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname); 223 224 #define MAKE_SYSENT_COMPAT(syscallname) \ 225 static struct sysent syscallname##_sysent = { \ 226 (sizeof(struct syscallname ## _args ) \ 227 / sizeof(register_t)), \ 228 (sy_call_t *)& syscallname, \ 229 SYS_AUE_##syscallname \ 230 } 231 232 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ 233 static struct syscall_module_data name##_syscall_mod = { \ 234 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \ 235 }; \ 236 \ 237 static moduledata_t name##_mod = { \ 238 "sys/" #name, \ 239 syscall_module_handler, \ 240 &name##_syscall_mod \ 241 }; \ 242 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE) 243 244 #define SYSCALL_MODULE_HELPER(syscallname) \ 245 static int syscallname##_syscall = SYS_##syscallname; \ 246 MAKE_SYSENT(syscallname); \ 247 SYSCALL_MODULE(syscallname, \ 248 & syscallname##_syscall, & syscallname##_sysent, \ 249 NULL, NULL) 250 251 #define SYSCALL_MODULE_PRESENT(syscallname) \ 252 (sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys && \ 253 sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys) 254 255 /* 256 * Syscall registration helpers with resource allocation handling. 257 */ 258 struct syscall_helper_data { 259 struct sysent new_sysent; 260 struct sysent old_sysent; 261 int syscall_no; 262 int registered; 263 }; 264 #define SYSCALL_INIT_HELPER_F(syscallname, flags) { \ 265 .new_sysent = { \ 266 .sy_narg = (sizeof(struct syscallname ## _args ) \ 267 / sizeof(register_t)), \ 268 .sy_call = (sy_call_t *)& sys_ ## syscallname, \ 269 .sy_auevent = SYS_AUE_##syscallname, \ 270 .sy_flags = (flags) \ 271 }, \ 272 .syscall_no = SYS_##syscallname \ 273 } 274 #define SYSCALL_INIT_HELPER_COMPAT_F(syscallname, flags) { \ 275 .new_sysent = { \ 276 .sy_narg = (sizeof(struct syscallname ## _args ) \ 277 / sizeof(register_t)), \ 278 .sy_call = (sy_call_t *)& syscallname, \ 279 .sy_auevent = SYS_AUE_##syscallname, \ 280 .sy_flags = (flags) \ 281 }, \ 282 .syscall_no = SYS_##syscallname \ 283 } 284 #define SYSCALL_INIT_HELPER(syscallname) \ 285 SYSCALL_INIT_HELPER_F(syscallname, 0) 286 #define SYSCALL_INIT_HELPER_COMPAT(syscallname) \ 287 SYSCALL_INIT_HELPER_COMPAT_F(syscallname, 0) 288 #define SYSCALL_INIT_LAST { \ 289 .syscall_no = NO_SYSCALL \ 290 } 291 292 int syscall_module_handler(struct module *mod, int what, void *arg); 293 int syscall_helper_register(struct syscall_helper_data *sd, int flags); 294 int syscall_helper_unregister(struct syscall_helper_data *sd); 295 /* Implementation, exposed for COMPAT code */ 296 int kern_syscall_register(struct sysent *sysents, int *offset, 297 struct sysent *new_sysent, struct sysent *old_sysent, int flags); 298 int kern_syscall_deregister(struct sysent *sysents, int offset, 299 const struct sysent *old_sysent); 300 int kern_syscall_module_handler(struct sysent *sysents, 301 struct module *mod, int what, void *arg); 302 int kern_syscall_helper_register(struct sysent *sysents, 303 struct syscall_helper_data *sd, int flags); 304 int kern_syscall_helper_unregister(struct sysent *sysents, 305 struct syscall_helper_data *sd); 306 307 struct proc; 308 const char *syscallname(struct proc *p, u_int code); 309 310 /* Special purpose system call functions. */ 311 struct nosys_args; 312 313 int lkmnosys(struct thread *, struct nosys_args *); 314 int lkmressys(struct thread *, struct nosys_args *); 315 316 int syscall_thread_enter(struct thread *td, struct sysent *se); 317 void syscall_thread_exit(struct thread *td, struct sysent *se); 318 319 int shared_page_alloc(int size, int align); 320 int shared_page_fill(int size, int align, const void *data); 321 void shared_page_write(int base, int size, const void *data); 322 void exec_sysvec_init(void *param); 323 void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2); 324 void exec_inittk(void); 325 326 void exit_onexit(struct proc *p); 327 void exec_free_abi_mappings(struct proc *p); 328 void exec_onexec_old(struct thread *td); 329 330 #define INIT_SYSENTVEC(name, sv) \ 331 SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY, \ 332 (sysinit_cfunc_t)exec_sysvec_init, sv); 333 334 #endif /* _KERNEL */ 335 336 #endif /* !_SYS_SYSENT_H_ */ 337