master
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_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
191extern struct sysentvec aout_sysvec;
192extern struct sysent sysent[];
193extern const char *syscallnames[];
194extern struct sysent nosys_sysent;
195
196struct nosys_args {
197 register_t dummy;
198};
199
200int nosys(struct thread *, struct nosys_args *);
201
202#define NO_SYSCALL (-1)
203
204struct module;
205
206struct 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) \
229static struct sysent syscallname##_sysent = SYSENT_INIT_VALS(syscallname);
230
231#define MAKE_SYSENT_COMPAT(syscallname) \
232static 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) \
240static struct syscall_module_data name##_syscall_mod = { \
241 evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL } \
242}; \
243 \
244static moduledata_t name##_mod = { \
245 "sys/" #name, \
246 syscall_module_handler, \
247 &name##_syscall_mod \
248}; \
249DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE)
250
251#define SYSCALL_MODULE_HELPER(syscallname) \
252static int syscallname##_syscall = SYS_##syscallname; \
253MAKE_SYSENT(syscallname); \
254SYSCALL_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 */
265struct 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
299int syscall_module_handler(struct module *mod, int what, void *arg);
300int syscall_helper_register(struct syscall_helper_data *sd, int flags);
301int syscall_helper_unregister(struct syscall_helper_data *sd);
302/* Implementation, exposed for COMPAT code */
303int kern_syscall_register(struct sysent *sysents, int *offset,
304 struct sysent *new_sysent, struct sysent *old_sysent, int flags);
305int kern_syscall_deregister(struct sysent *sysents, int offset,
306 const struct sysent *old_sysent);
307int kern_syscall_module_handler(struct sysent *sysents,
308 struct module *mod, int what, void *arg);
309int kern_syscall_helper_register(struct sysent *sysents,
310 struct syscall_helper_data *sd, int flags);
311int kern_syscall_helper_unregister(struct sysent *sysents,
312 struct syscall_helper_data *sd);
313
314struct proc;
315const char *syscallname(struct proc *p, u_int code);
316
317/* Special purpose system call functions. */
318struct nosys_args;
319
320int lkmnosys(struct thread *, struct nosys_args *);
321int lkmressys(struct thread *, struct nosys_args *);
322
323int syscall_thread_enter(struct thread *td, struct sysent **se);
324void syscall_thread_exit(struct thread *td, struct sysent *se);
325
326int shared_page_alloc(int size, int align);
327int shared_page_fill(int size, int align, const void *data);
328void shared_page_write(int base, int size, const void *data);
329void exec_sysvec_init(void *param);
330void exec_sysvec_init_secondary(struct sysentvec *sv, struct sysentvec *sv2);
331void exec_inittk(void);
332
333void exit_onexit(struct proc *p);
334void exec_free_abi_mappings(struct proc *p);
335void 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_ */