xref: /freebsd/sys/sys/sysent.h (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
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  * $FreeBSD$
30  */
31 
32 #ifndef _SYS_SYSENT_H_
33 #define	_SYS_SYSENT_H_
34 
35 #include <bsm/audit.h>
36 
37 struct rlimit;
38 struct sysent;
39 struct thread;
40 struct ksiginfo;
41 
42 typedef	int	sy_call_t(struct thread *, void *);
43 
44 /* Used by the machine dependent syscall() code. */
45 typedef	void (*systrace_probe_func_t)(u_int32_t, int, struct sysent *, void *);
46 
47 /*
48  * Used by loaded syscalls to convert arguments to a DTrace array
49  * of 64-bit arguments.
50  */
51 typedef	void (*systrace_args_func_t)(void *, u_int64_t *, int *);
52 
53 extern systrace_probe_func_t	systrace_probe_func;
54 
55 struct sysent {		/* system call table */
56 	int	sy_narg;	/* number of arguments */
57 	sy_call_t *sy_call;	/* implementing function */
58 	au_event_t sy_auevent;	/* audit event associated with syscall */
59 	systrace_args_func_t sy_systrace_args_func;
60 				/* optional argument conversion function. */
61 	u_int32_t sy_entry;	/* DTrace entry ID for systrace. */
62 	u_int32_t sy_return;	/* DTrace return ID for systrace. */
63 };
64 
65 struct image_params;
66 struct __sigset;
67 struct trapframe;
68 struct vnode;
69 
70 struct sysentvec {
71 	int		sv_size;	/* number of entries */
72 	struct sysent	*sv_table;	/* pointer to sysent */
73 	u_int		sv_mask;	/* optional mask to index */
74 	int		sv_sigsize;	/* size of signal translation table */
75 	int		*sv_sigtbl;	/* signal translation table */
76 	int		sv_errsize;	/* size of errno translation table */
77 	int 		*sv_errtbl;	/* errno translation table */
78 	int		(*sv_transtrap)(int, int);
79 					/* translate trap-to-signal mapping */
80 	int		(*sv_fixup)(register_t **, struct image_params *);
81 					/* stack fixup function */
82 	void		(*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *);
83 			    		/* send signal */
84 	char 		*sv_sigcode;	/* start of sigtramp code */
85 	int 		*sv_szsigcode;	/* size of sigtramp code */
86 	void		(*sv_prepsyscall)(struct trapframe *, int *, u_int *,
87 			    caddr_t *);
88 	char		*sv_name;	/* name of binary type */
89 	int		(*sv_coredump)(struct thread *, struct vnode *, off_t);
90 					/* function to dump core, or NULL */
91 	int		(*sv_imgact_try)(struct image_params *);
92 	int		sv_minsigstksz;	/* minimum signal stack size */
93 	int		sv_pagesize;	/* pagesize */
94 	vm_offset_t	sv_minuser;	/* VM_MIN_ADDRESS */
95 	vm_offset_t	sv_maxuser;	/* VM_MAXUSER_ADDRESS */
96 	vm_offset_t	sv_usrstack;	/* USRSTACK */
97 	vm_offset_t	sv_psstrings;	/* PS_STRINGS */
98 	int		sv_stackprot;	/* vm protection for stack */
99 	register_t	*(*sv_copyout_strings)(struct image_params *);
100 	void		(*sv_setregs)(struct thread *, u_long, u_long, u_long);
101 	void		(*sv_fixlimit)(struct rlimit *, int);
102 	u_long		*sv_maxssiz;
103 };
104 
105 #ifdef _KERNEL
106 extern struct sysentvec aout_sysvec;
107 extern struct sysentvec elf_freebsd_sysvec;
108 extern struct sysentvec null_sysvec;
109 extern struct sysent sysent[];
110 
111 #define NO_SYSCALL (-1)
112 
113 struct module;
114 
115 struct syscall_module_data {
116        int     (*chainevh)(struct module *, int, void *); /* next handler */
117        void    *chainarg;      /* arg for next event handler */
118        int     *offset;         /* offset into sysent */
119        struct  sysent *new_sysent; /* new sysent */
120        struct  sysent old_sysent; /* old sysent */
121 };
122 
123 #define MAKE_SYSENT(syscallname)                        \
124 static struct sysent syscallname##_sysent = {           \
125     (sizeof(struct syscallname ## _args )               \
126      / sizeof(register_t)),                             \
127     (sy_call_t *)& syscallname,                         \
128     SYS_AUE_##syscallname                               \
129 }
130 
131 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg)     \
132 static struct syscall_module_data name##_syscall_mod = {       \
133        evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL }     \
134 };                                                             \
135                                                                \
136 static moduledata_t name##_mod = {                             \
137        #name,                                                  \
138        syscall_module_handler,                                 \
139        &name##_syscall_mod                                     \
140 };                                                             \
141 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE)
142 
143 #define SYSCALL_MODULE_HELPER(syscallname)              \
144 static int syscallname##_syscall = SYS_##syscallname;   \
145 MAKE_SYSENT(syscallname);                               \
146 SYSCALL_MODULE(syscallname,                             \
147     & syscallname##_syscall, & syscallname##_sysent,    \
148     NULL, NULL);
149 
150 #define SYSCALL_MODULE_PRESENT(syscallname)		\
151 	(sysent[SYS_##syscallname].sy_call !=		\
152 			(sy_call_t *)lkmnosys &&	\
153 	sysent[SYS_##syscallname].sy_call !=		\
154 			(sy_call_t *)lkmressys)
155 
156 int    syscall_register(int *offset, struct sysent *new_sysent,
157 	    struct sysent *old_sysent);
158 int    syscall_deregister(int *offset, struct sysent *old_sysent);
159 int    syscall_module_handler(struct module *mod, int what, void *arg);
160 
161 #endif /* _KERNEL */
162 
163 #endif /* !_SYS_SYSENT_H_ */
164