1 /* $OpenBSD: procfs_cmdline.c,v 1.4 2004/05/05 23:52:09 tedu Exp $ */
2 /* $NetBSD: procfs_cmdline.c,v 1.3 1999/03/13 22:26:48 thorpej Exp $ */
3
4 /*
5 * Copyright (c) 1999 Jaromir Dolecek <dolecek@ics.muni.cz>
6 * Copyright (c) 1999 The NetBSD Foundation, Inc.
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to The NetBSD Foundation
10 * by Jaromir Dolecek.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the NetBSD
23 * Foundation, Inc. and its contributors.
24 * 4. Neither the name of The NetBSD Foundation nor the names of its
25 * contributors may be used to endorse or promote products derived
26 * from this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
30 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
31 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
32 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 */
40
41 #include <sys/param.h>
42 #include <sys/types.h>
43 #include <sys/systm.h>
44 #include <sys/syslimits.h>
45 #include <sys/proc.h>
46 #include <sys/vnode.h>
47 #include <sys/exec.h>
48 #include <sys/malloc.h>
49 #include <miscfs/procfs/procfs.h>
50 #include <uvm/uvm_extern.h>
51
52 /*
53 * code for returning process's command line arguments
54 */
55 int
procfs_docmdline(curp,p,pfs,uio)56 procfs_docmdline(curp, p, pfs, uio)
57 struct proc *curp;
58 struct proc *p;
59 struct pfsnode *pfs;
60 struct uio *uio;
61 {
62 struct ps_strings pss;
63 int count, error, i;
64 size_t len, xlen, upper_bound;
65 struct uio auio;
66 struct iovec aiov;
67 vaddr_t argv;
68 char *arg;
69
70 /* Don't allow writing. */
71 if (uio->uio_rw != UIO_READ)
72 return (EOPNOTSUPP);
73
74 /*
75 * Allocate a temporary buffer to hold the arguments.
76 */
77 arg = malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
78
79 /*
80 * Zombies don't have a stack, so we can't read their psstrings.
81 * System processes also don't have a user stack. This is what
82 * ps(1) would display.
83 */
84 if (P_ZOMBIE(p) || (p->p_flag & P_SYSTEM) != 0) {
85 len = snprintf(arg, PAGE_SIZE, "(%s)", p->p_comm);
86 if (uio->uio_offset >= (off_t)len)
87 error = 0;
88 else
89 error = uiomove(arg, len - uio->uio_offset, uio);
90
91 free(arg, M_TEMP);
92 return (error);
93 }
94
95 /*
96 * NOTE: Don't bother doing a procfs_checkioperm() here
97 * because the psstrings info is available by using ps(1),
98 * so it's not like there's anything to protect here.
99 */
100
101 /*
102 * Lock the process down in memory.
103 */
104 /* XXXCDC: how should locking work here? */
105 if ((p->p_flag & P_WEXIT) || (p->p_vmspace->vm_refcnt < 1)) {
106 free(arg, M_TEMP);
107 return (EFAULT);
108 }
109 PHOLD(p);
110 p->p_vmspace->vm_refcnt++; /* XXX */
111
112 /*
113 * Read in the ps_strings structure.
114 */
115 aiov.iov_base = &pss;
116 aiov.iov_len = sizeof(pss);
117 auio.uio_iov = &aiov;
118 auio.uio_iovcnt = 1;
119 auio.uio_offset = (vaddr_t)PS_STRINGS;
120 auio.uio_resid = sizeof(pss);
121 auio.uio_segflg = UIO_SYSSPACE;
122 auio.uio_rw = UIO_READ;
123 auio.uio_procp = NULL;
124 error = uvm_io(&p->p_vmspace->vm_map, &auio);
125 if (error)
126 goto bad;
127
128 /*
129 * Now read the address of the argument vector.
130 */
131 aiov.iov_base = &argv;
132 aiov.iov_len = sizeof(argv);
133 auio.uio_iov = &aiov;
134 auio.uio_iovcnt = 1;
135 auio.uio_offset = (vaddr_t)pss.ps_argvstr;
136 auio.uio_resid = sizeof(argv);
137 auio.uio_segflg = UIO_SYSSPACE;
138 auio.uio_rw = UIO_READ;
139 auio.uio_procp = NULL;
140 error = uvm_io(&p->p_vmspace->vm_map, &auio);
141 if (error)
142 goto bad;
143
144 /*
145 * Now copy in the actual argument vector, one byte at a time,
146 * since we don't know how long the vector is (though, we do
147 * know how many NUL-terminated strings are in the vector).
148 */
149 len = 0;
150 count = pss.ps_nargvstr;
151 upper_bound = round_page(uio->uio_offset + uio->uio_resid);
152 for (; count && len < upper_bound; len += xlen) {
153 aiov.iov_base = arg;
154 aiov.iov_len = PAGE_SIZE;
155 auio.uio_iov = &aiov;
156 auio.uio_iovcnt = 1;
157 auio.uio_offset = argv + len;
158 xlen = PAGE_SIZE - ((argv + len) & PAGE_MASK);
159 auio.uio_resid = xlen;
160 auio.uio_segflg = UIO_SYSSPACE;
161 auio.uio_rw = UIO_READ;
162 auio.uio_procp = NULL;
163 error = uvm_io(&p->p_vmspace->vm_map, &auio);
164 if (error)
165 goto bad;
166
167 for (i = 0; i < xlen && count != 0; i++) {
168 if (arg[i] == '\0')
169 count--; /* one full string */
170 }
171
172 if (count == 0)
173 i--; /* exclude the final NUL */
174
175 if (len + i > uio->uio_offset) {
176 /* Have data in this page, copy it out */
177 error = uiomove(arg + uio->uio_offset - len,
178 i + len - uio->uio_offset, uio);
179 if (error || uio->uio_resid <= 0)
180 break;
181 }
182 }
183
184
185 bad:
186 PRELE(p);
187 uvmspace_free(p->p_vmspace);
188 free(arg, M_TEMP);
189 return (error);
190 }
191