xref: /freebsd/sys/fs/procfs/procfs.c (revision 5d10e1f7dfbe41e77a7bccca3740086b848df587)
1 /*
2  * Copyright (c) 2001 Dag-Erling Sm�rgrav
3  * Copyright (c) 1993 Jan-Simon Pendry
4  * Copyright (c) 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Jan-Simon Pendry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)procfs_vfsops.c	8.7 (Berkeley) 5/10/95
39  *
40  * $FreeBSD$
41  */
42 
43 #include <sys/param.h>
44 #include <sys/queue.h>
45 #include <sys/exec.h>
46 #include <sys/lock.h>
47 #include <sys/kernel.h>
48 #include <sys/malloc.h>
49 #include <sys/mount.h>
50 #include <sys/mutex.h>
51 #include <sys/proc.h>
52 #include <sys/sbuf.h>
53 #include <sys/sysproto.h>
54 #include <sys/systm.h>
55 #include <sys/vnode.h>
56 
57 #include <vm/vm.h>
58 #include <vm/pmap.h>
59 #include <vm/vm_param.h>
60 
61 #include <fs/pseudofs/pseudofs.h>
62 #include <fs/procfs/procfs.h>
63 
64 /*
65  * Filler function for proc/pid/self
66  */
67 int
68 procfs_doprocfile(PFS_FILL_ARGS)
69 {
70 	char *fullpath = "unknown";
71 	char *freepath = NULL;
72 
73 	vn_fullpath(td, p->p_textvp, &fullpath, &freepath);
74 	sbuf_printf(sb, "%s", fullpath);
75 	if (freepath)
76 		free(freepath, M_TEMP);
77 	return (0);
78 }
79 
80 /*
81  * Filler function for proc/curproc
82  */
83 int
84 procfs_docurproc(PFS_FILL_ARGS)
85 {
86 	sbuf_printf(sb, "%ld", (long)td->td_proc->p_pid);
87 	return (0);
88 }
89 
90 /*
91  * Adjust mode for some nodes that need it
92  */
93 int
94 procfs_attr(PFS_ATTR_ARGS)
95 {
96 	/* XXX inefficient, split into separate functions */
97 	if (p->p_flag & P_SUGID)
98 		vap->va_mode = 0;
99 	else if (strcmp(pn->pn_name, "ctl") == 0 ||
100 	    strcmp(pn->pn_name, "note") == 0 ||
101 	    strcmp(pn->pn_name, "notepg") == 0)
102 		vap->va_mode = 0200;
103 	else if (strcmp(pn->pn_name, "mem") == 0 ||
104 	    strcmp(pn->pn_name, "regs") == 0 ||
105 	    strcmp(pn->pn_name, "dbregs") == 0 ||
106 	    strcmp(pn->pn_name, "fpregs") == 0)
107 		vap->va_mode = 0600;
108 
109 	/* p is locked by caller */
110 	PROC_LOCK_ASSERT(p, MA_OWNED);
111 	vap->va_uid = p->p_ucred->cr_uid;
112 	vap->va_gid = p->p_ucred->cr_gid;
113 
114 	return (0);
115 }
116 
117 /*
118  * Visibility: some files only exist for non-system processes
119  * Non-static because linprocfs uses it.
120  */
121 int
122 procfs_notsystem(PFS_VIS_ARGS)
123 {
124 	return ((p->p_flag & P_SYSTEM) == 0);
125 }
126 
127 /*
128  * Visibility: some files are only visible to process that can debug
129  * the target process.
130  */
131 int
132 procfs_candebug(PFS_VIS_ARGS)
133 {
134 	PROC_LOCK_ASSERT(p, MA_OWNED);
135 	return ((p->p_flag & P_SYSTEM) == 0 &&
136 	    p_candebug(td, p) == 0);
137 }
138 
139 /*
140  * Constructor
141  */
142 static int
143 procfs_init(PFS_INIT_ARGS)
144 {
145 	struct pfs_node *root;
146 	struct pfs_node *dir;
147 	struct pfs_node *node;
148 
149 	root = pi->pi_root;
150 
151 	pfs_create_link(root, "curproc", procfs_docurproc,
152 	    NULL, NULL, 0);
153 
154 	dir = pfs_create_dir(root, "pid",
155 	    procfs_attr, NULL, PFS_PROCDEP);
156 	pfs_create_file(dir, "cmdline", procfs_doproccmdline,
157 	    NULL, NULL, PFS_RD);
158 	pfs_create_file(dir, "ctl", procfs_doprocctl,
159 	    procfs_attr, NULL, PFS_WR);
160 	pfs_create_file(dir, "dbregs", procfs_doprocdbregs,
161 	    procfs_attr, procfs_candebug, PFS_RDWR|PFS_RAW);
162 	pfs_create_file(dir, "etype", procfs_doproctype,
163 	    NULL, NULL, PFS_RD);
164 	pfs_create_file(dir, "fpregs", procfs_doprocfpregs,
165 	    procfs_attr, procfs_candebug, PFS_RDWR|PFS_RAW);
166 	pfs_create_file(dir, "map", procfs_doprocmap,
167 	    NULL, procfs_notsystem, PFS_RD);
168 	node = pfs_create_file(dir, "mem", procfs_doprocmem,
169 	    procfs_attr, procfs_candebug, PFS_RDWR|PFS_RAW);
170 	node->pn_ioctl = procfs_ioctl;
171 	node->pn_close = procfs_close;
172 	pfs_create_file(dir, "note", procfs_doprocnote,
173 	    procfs_attr, procfs_candebug, PFS_WR);
174 	pfs_create_file(dir, "notepg", procfs_doprocnote,
175 	    procfs_attr, procfs_candebug, PFS_WR);
176 	pfs_create_file(dir, "regs", procfs_doprocregs,
177 	    procfs_attr, procfs_candebug, PFS_RDWR|PFS_RAW);
178 	pfs_create_file(dir, "rlimit", procfs_doprocrlimit,
179 	    NULL, NULL, PFS_RD);
180 	pfs_create_file(dir, "status", procfs_doprocstatus,
181 	    NULL, NULL, PFS_RD);
182 
183 	pfs_create_link(dir, "file", procfs_doprocfile,
184 	    NULL, procfs_notsystem, 0);
185 
186 	return (0);
187 }
188 
189 /*
190  * Destructor
191  */
192 static int
193 procfs_uninit(PFS_INIT_ARGS)
194 {
195 
196 	/* nothing to do, pseudofs will GC */
197 	return (0);
198 }
199 
200 PSEUDOFS(procfs, 1);
201