xref: /freebsd/sys/sys/sysent.h (revision 129d3046ef0427d3b22b78a71f3494854d817fba)
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)(int, 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 	u_int32_t sy_flags;	/* General flags for system calls. */
64 };
65 
66 struct image_params;
67 struct __sigset;
68 struct trapframe;
69 struct vnode;
70 
71 struct sysentvec {
72 	int		sv_size;	/* number of entries */
73 	struct sysent	*sv_table;	/* pointer to sysent */
74 	u_int		sv_mask;	/* optional mask to index */
75 	int		sv_sigsize;	/* size of signal translation table */
76 	int		*sv_sigtbl;	/* signal translation table */
77 	int		sv_errsize;	/* size of errno translation table */
78 	int 		*sv_errtbl;	/* errno translation table */
79 	int		(*sv_transtrap)(int, int);
80 					/* translate trap-to-signal mapping */
81 	int		(*sv_fixup)(register_t **, struct image_params *);
82 					/* stack fixup function */
83 	void		(*sv_sendsig)(void (*)(int), struct ksiginfo *, struct __sigset *);
84 			    		/* send signal */
85 	char 		*sv_sigcode;	/* start of sigtramp code */
86 	int 		*sv_szsigcode;	/* size of sigtramp code */
87 	void		(*sv_prepsyscall)(struct trapframe *, int *, u_int *,
88 			    caddr_t *);
89 	char		*sv_name;	/* name of binary type */
90 	int		(*sv_coredump)(struct thread *, struct vnode *, off_t);
91 					/* function to dump core, or NULL */
92 	int		(*sv_imgact_try)(struct image_params *);
93 	int		sv_minsigstksz;	/* minimum signal stack size */
94 	int		sv_pagesize;	/* pagesize */
95 	vm_offset_t	sv_minuser;	/* VM_MIN_ADDRESS */
96 	vm_offset_t	sv_maxuser;	/* VM_MAXUSER_ADDRESS */
97 	vm_offset_t	sv_usrstack;	/* USRSTACK */
98 	vm_offset_t	sv_psstrings;	/* PS_STRINGS */
99 	int		sv_stackprot;	/* vm protection for stack */
100 	register_t	*(*sv_copyout_strings)(struct image_params *);
101 	void		(*sv_setregs)(struct thread *, u_long, u_long, u_long);
102 	void		(*sv_fixlimit)(struct rlimit *, int);
103 	u_long		*sv_maxssiz;
104 	u_int		sv_flags;
105 };
106 
107 #define	SV_ILP32	0x000100
108 #define	SV_LP64		0x000200
109 #define	SV_IA32		0x004000
110 #define	SV_AOUT		0x008000
111 
112 #define	SV_ABI_MASK	0xff
113 #define	SV_CURPROC_FLAG(x) (curproc->p_sysent->sv_flags & (x))
114 #define	SV_CURPROC_ABI() (curproc->p_sysent->sv_flags & SV_ABI_MASK)
115 /* same as ELFOSABI_XXX, to prevent header pollution */
116 #define	SV_ABI_LINUX	3
117 #define	SV_ABI_FREEBSD 	9
118 #define	SV_ABI_UNDEF	255
119 
120 #ifdef _KERNEL
121 extern struct sysentvec aout_sysvec;
122 extern struct sysentvec elf_freebsd_sysvec;
123 extern struct sysentvec null_sysvec;
124 extern struct sysent sysent[];
125 
126 #define	NO_SYSCALL (-1)
127 
128 struct module;
129 
130 struct syscall_module_data {
131 	int	(*chainevh)(struct module *, int, void *); /* next handler */
132 	void	*chainarg;		/* arg for next event handler */
133 	int	*offset;		/* offset into sysent */
134 	struct sysent *new_sysent;	/* new sysent */
135 	struct sysent old_sysent;	/* old sysent */
136 };
137 
138 #define	MAKE_SYSENT(syscallname)				\
139 static struct sysent syscallname##_sysent = {			\
140 	(sizeof(struct syscallname ## _args )			\
141 	    / sizeof(register_t)),				\
142 	(sy_call_t *)& syscallname,				\
143 	SYS_AUE_##syscallname					\
144 }
145 
146 #define SYSCALL_MODULE(name, offset, new_sysent, evh, arg)	\
147 static struct syscall_module_data name##_syscall_mod = {	\
148 	evh, arg, offset, new_sysent, { 0, NULL, AUE_NULL }	\
149 };								\
150 								\
151 static moduledata_t name##_mod = {				\
152 	#name,							\
153 	syscall_module_handler,					\
154 	&name##_syscall_mod					\
155 };								\
156 DECLARE_MODULE(name, name##_mod, SI_SUB_SYSCALLS, SI_ORDER_MIDDLE)
157 
158 #define	SYSCALL_MODULE_HELPER(syscallname)			\
159 static int syscallname##_syscall = SYS_##syscallname;		\
160 MAKE_SYSENT(syscallname);					\
161 SYSCALL_MODULE(syscallname,					\
162     & syscallname##_syscall, & syscallname##_sysent,		\
163     NULL, NULL)
164 
165 #define	SYSCALL_MODULE_PRESENT(syscallname)				\
166 	(sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmnosys &&	\
167 	sysent[SYS_##syscallname].sy_call != (sy_call_t *)lkmressys)
168 
169 int	syscall_register(int *offset, struct sysent *new_sysent,
170 	    struct sysent *old_sysent);
171 int	syscall_deregister(int *offset, struct sysent *old_sysent);
172 int	syscall_module_handler(struct module *mod, int what, void *arg);
173 
174 /* Special purpose system call functions. */
175 struct nosys_args;
176 
177 int	lkmnosys(struct thread *, struct nosys_args *);
178 int	lkmressys(struct thread *, struct nosys_args *);
179 
180 #endif /* _KERNEL */
181 
182 #endif /* !_SYS_SYSENT_H_ */
183