sysent.h revision 293490 
1/*-
2 * Copyright (c) 1982, 1988, 1991 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: stable/10/sys/sys/sysent.h 293490 2016-01-09 14:53:08Z dchagin $
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;
41
42typedef	int	sy_call_t(struct thread *, void *);
43
44/* Used by the machine dependent syscall() code. */
45typedef	void (*systrace_probe_func_t)(u_int32_t, int, struct sysent *, void *,
46    int);
47
48/*
49 * Used by loaded syscalls to convert arguments to a DTrace array
50 * of 64-bit arguments.
51 */
52typedef	void (*systrace_args_func_t)(int, void *, u_int64_t *, int *);
53
54extern systrace_probe_func_t	systrace_probe_func;
55
56struct sysent {			/* system call table */
57	int	sy_narg;	/* number of arguments */
58	sy_call_t *sy_call;	/* implementing function */
59	au_event_t sy_auevent;	/* audit event associated with syscall */
60	systrace_args_func_t sy_systrace_args_func;
61				/* optional argument conversion function. */
62	u_int32_t sy_entry;	/* DTrace entry ID for systrace. */
63	u_int32_t sy_return;	/* DTrace return ID for systrace. */
64	u_int32_t sy_flags;	/* General flags for system calls. */
65	u_int32_t sy_thrcnt;
66};
67
68/*
69 * A system call is permitted in capability mode.
70 */
71#define	SYF_CAPENABLED	0x00000001
72
73#define	SY_THR_FLAGMASK	0x7
74#define	SY_THR_STATIC	0x1
75#define	SY_THR_DRAINING	0x2
76#define	SY_THR_ABSENT	0x4
77#define	SY_THR_INCR	0x8
78
79struct image_params;
80struct __sigset;
81struct syscall_args;
82struct trapframe;
83struct vnode;
84
85struct sysentvec {
86	int		sv_size;	/* number of entries */
87	struct sysent	*sv_table;	/* pointer to sysent */
88	u_int		sv_mask;	/* optional mask to index */
89	int		sv_sigsize;	/* size of signal translation table */
90	int		*sv_sigtbl;	/* signal translation table */
91	int		sv_errsize;	/* size of errno translation table */
92	int 		*sv_errtbl;	/* errno translation table */
93	int		(*sv_transtrap)(int, int);
94					/* translate trap-to-signal mapping */
95	int		(*sv_fixup)(register_t **, struct image_params *);
96					/* stack fixup function */
97	void		(*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *);
98			    		/* send signal */
99	char 		*sv_sigcode;	/* start of sigtramp code */
100	int 		*sv_szsigcode;	/* size of sigtramp code */
101	void		(*sv_prepsyscall)(struct trapframe *, int *, u_int *,
102			    caddr_t *);
103	char		*sv_name;	/* name of binary type */
104	int		(*sv_coredump)(struct thread *, struct vnode *, off_t, int);
105					/* function to dump core, or NULL */
106	int		(*sv_imgact_try)(struct image_params *);
107	int		sv_minsigstksz;	/* minimum signal stack size */
108	int		sv_pagesize;	/* pagesize */
109	vm_offset_t	sv_minuser;	/* VM_MIN_ADDRESS */
110	vm_offset_t	sv_maxuser;	/* VM_MAXUSER_ADDRESS */
111	vm_offset_t	sv_usrstack;	/* USRSTACK */
112	vm_offset_t	sv_psstrings;	/* PS_STRINGS */
113	int		sv_stackprot;	/* vm protection for stack */
114	register_t	*(*sv_copyout_strings)(struct image_params *);
115	void		(*sv_setregs)(struct thread *, struct image_params *,
116			    u_long);
117	void		(*sv_fixlimit)(struct rlimit *, int);
118	u_long		*sv_maxssiz;
119	u_int		sv_flags;
120	void		(*sv_set_syscall_retval)(struct thread *, int);
121	int		(*sv_fetch_syscall_args)(struct thread *, struct
122			    syscall_args *);
123	const char	**sv_syscallnames;
124	vm_offset_t	sv_shared_page_base;
125	vm_offset_t	sv_shared_page_len;
126	vm_offset_t	sv_sigcode_base;
127	vm_offset_t	sv_timekeep_base;
128	int		sv_timekeep_off;
129	int		sv_timekeep_curr;
130	uint32_t	sv_timekeep_gen;
131	void		*sv_shared_page_obj;
132	void		(*sv_schedtail)(struct thread *);
133	void		(*sv_thread_detach)(struct thread *);
134};
135
136#define	SV_ILP32	0x000100
137#define	SV_LP64		0x000200
138#define	SV_IA32		0x004000
139#define	SV_AOUT		0x008000
140#define	SV_SHP		0x010000
141
142#define	SV_ABI_MASK	0xff
143#define	SV_PROC_FLAG(p, x)	((p)->p_sysent->sv_flags & (x))
144#define	SV_PROC_ABI(p)		((p)->p_sysent->sv_flags & SV_ABI_MASK)
145#define	SV_CURPROC_FLAG(x)	SV_PROC_FLAG(curproc, x)
146#define	SV_CURPROC_ABI()	SV_PROC_ABI(curproc)
147/* same as ELFOSABI_XXX, to prevent header pollution */
148#define	SV_ABI_LINUX	3
149#define	SV_ABI_FREEBSD 	9
150#define	SV_ABI_UNDEF	255
151
152#ifdef _KERNEL
153extern struct sysentvec aout_sysvec;
154extern struct sysentvec elf_freebsd_sysvec;
155extern struct sysentvec null_sysvec;
156extern struct sysent sysent[];
157extern const char *syscallnames[];
158
159#if defined(__amd64__) || defined(__ia64__)
160extern int i386_read_exec;
161#endif
162
163#define	NO_SYSCALL (-1)
164
165struct module;
166
167struct syscall_module_data {
168	int	(*chainevh)(struct module *, int, void *); /* next handler */
169	void	*chainarg;		/* arg for next event handler */
170	int	*offset;		/* offset into sysent */
171	struct sysent *new_sysent;	/* new sysent */
172	struct sysent old_sysent;	/* old sysent */
173};
174
175#define	MAKE_SYSENT(syscallname)				\
176static struct sysent syscallname##_sysent = {			\
177	(sizeof(struct syscallname ## _args )			\
178	    / sizeof(register_t)),				\
179	(sy_call_t *)& sys_##syscallname,	       		\
180	SYS_AUE_##syscallname					\
181}
182
183#define	MAKE_SYSENT_COMPAT(syscallname)				\
184static struct sysent syscallname##_sysent = {			\
185	(sizeof(struct syscallname ## _args )			\
186	    / sizeof(register_t)),				\
187	(sy_call_t *)& syscallname,				\
188	SYS_AUE_##syscallname					\
189}
190
191#define SYSCALL_MODULE(name, offset, new_sysent, evh, arg)	\
192static struct syscall_module_data name##_syscall_mod = {	\
193	evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL }	\
194};								\
195								\
196static moduledata_t name##_mod = {				\
197	"sys/" #name,						\
198	syscall_module_handler,					\
199	&name##_syscall_mod					\
200};								\
201DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE)
202
203#define	SYSCALL_MODULE_HELPER(syscallname)			\
204static int syscallname##_syscall = SYS_##syscallname;		\
205MAKE_SYSENT(syscallname);					\
206SYSCALL_MODULE(syscallname,					\
207    & syscallname##_syscall, & syscallname##_sysent,		\
208    NULL, NULL)
209
210#define	SYSCALL_MODULE_PRESENT(syscallname)				\
211	(sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys &&	\
212	sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys)
213
214/*
215 * Syscall registration helpers with resource allocation handling.
216 */
217struct syscall_helper_data {
218	struct sysent new_sysent;
219	struct sysent old_sysent;
220	int syscall_no;
221	int registered;
222};
223#define SYSCALL_INIT_HELPER(syscallname) {			\
224    .new_sysent = {						\
225	.sy_narg = (sizeof(struct syscallname ## _args )	\
226	    / sizeof(register_t)),				\
227	.sy_call = (sy_call_t *)& sys_ ## syscallname,		\
228	.sy_auevent = SYS_AUE_##syscallname			\
229    },								\
230    .syscall_no = SYS_##syscallname				\
231}
232#define SYSCALL_INIT_HELPER_COMPAT(syscallname) {		\
233    .new_sysent = {						\
234	.sy_narg = (sizeof(struct syscallname ## _args )	\
235	    / sizeof(register_t)),				\
236	.sy_call = (sy_call_t *)& syscallname,			\
237	.sy_auevent = SYS_AUE_##syscallname			\
238    },								\
239    .syscall_no = SYS_##syscallname				\
240}
241#define SYSCALL_INIT_LAST {					\
242    .syscall_no = NO_SYSCALL					\
243}
244
245int	syscall_register(int *offset, struct sysent *new_sysent,
246	    struct sysent *old_sysent);
247int	syscall_deregister(int *offset, struct sysent *old_sysent);
248int	syscall_module_handler(struct module *mod, int what, void *arg);
249int	syscall_helper_register(struct syscall_helper_data *sd);
250int	syscall_helper_unregister(struct syscall_helper_data *sd);
251
252struct proc;
253const char *syscallname(struct proc *p, u_int code);
254
255/* Special purpose system call functions. */
256struct nosys_args;
257
258int	lkmnosys(struct thread *, struct nosys_args *);
259int	lkmressys(struct thread *, struct nosys_args *);
260
261int	syscall_thread_enter(struct thread *td, struct sysent *se);
262void	syscall_thread_exit(struct thread *td, struct sysent *se);
263
264int shared_page_alloc(int size, int align);
265int shared_page_fill(int size, int align, const void *data);
266void shared_page_write(int base, int size, const void *data);
267void exec_sysvec_init(void *param);
268
269#define INIT_SYSENTVEC(name, sv)					\
270    SYSINIT(name, SI_SUB_EXEC, SI_ORDER_ANY,				\
271	(sysinit_cfunc_t)exec_sysvec_init, sv);
272
273#endif /* _KERNEL */
274
275#endif /* !_SYS_SYSENT_H_ */
276