1 /*
2 * Copyright (c) 2005 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include "login_locl.h"
35
36 RCSID("$Id$");
37
38 #include <errno.h>
39 #include <limits.h>
40 #ifdef HAVE_SYS_RESOURCE_H
41 #include <sys/resource.h>
42 #endif
43
44 struct limit {
45 const char *name;
46 int resource;
47 int scale;
48 int has_limit;
49 struct rlimit limit;
50 } limits[] = {
51 #define LIM(X, S) { #X, RLIMIT_##X, S, 0 }
52 LIM(CORE, 1024),
53 LIM(CPU, 60),
54 LIM(DATA, 1024),
55 LIM(FSIZE, 1024),
56 #ifdef RLIMIT_MEMLOCK
57 LIM(MEMLOCK, 1024),
58 #endif
59 LIM(NOFILE, 1),
60 #ifdef RLIMIT_NPROC
61 LIM(NPROC, 1),
62 #endif
63 #ifdef RLIMIT_RSS
64 LIM(RSS, 1024),
65 #endif
66 LIM(STACK, 1024),
67
68 #ifdef RLIMIT_AS
69 LIM(AS, 1024),
70 #endif
71 #ifdef RLIMIT_LOCKS
72 LIM(LOCKS, 1),
73 #endif
74 /*
75 maxlogins
76 priority
77 */
78 { NULL, 0 }
79 };
80
81 static struct limit *
find_limit(const char * name)82 find_limit(const char *name)
83 {
84 struct limit *l;
85 for(l = limits; l->name != NULL; l++)
86 if(strcasecmp(name, l->name) == 0)
87 return l;
88 return NULL;
89 }
90
91 /* this function reads limits.conf files similar to pam_limits
92 unimplemented features include:
93 % maxlogins
94 "-" no limits,
95 priorities etc that are not set via setrlimit
96 XXX uses static storage, and clobbers getgr*
97 */
98
99 int
read_limits_conf(const char * file,const struct passwd * pwd)100 read_limits_conf(const char *file, const struct passwd *pwd)
101 {
102 FILE *f;
103 char *args[4];
104 int lineno = 0;
105 char buf[1024];
106 struct limit *l;
107 rlim_t value;
108
109 f = fopen(file, "r");
110 if(f == NULL) {
111 if(errno != ENOENT && errno != ENOTDIR)
112 syslog(LOG_ERR, "%s: %m", file);
113 return -1;
114 }
115
116 while(fgets(buf, sizeof(buf), f) != NULL) {
117 char *last = NULL;
118 char *end = NULL;
119 int level;
120
121 lineno++;
122
123 if(buf[0] == '\0') {
124 syslog(LOG_ERR, "%s: line %d: NUL character", file, lineno);
125 continue;
126 }
127 if(buf[strlen(buf) - 1] != '\n') {
128 /* file did not end with a newline, figure out if we're at
129 the EOF, or if our buffer was too small */
130 int eof = 1;
131 int c;
132 while((c = fgetc(f)) != EOF) {
133 eof = 0;
134 if(c == '\n')
135 break;
136 }
137 if(!eof) {
138 syslog(LOG_ERR, "%s: line %d: line too long", file, lineno);
139 continue;
140 }
141 }
142 buf[strcspn(buf, "#\r\n")] = '\0';
143 if((args[0] = strtok_r(buf, " \t", &last)) == NULL ||
144 (args[1] = strtok_r(NULL, " \t", &last)) == NULL ||
145 (args[2] = strtok_r(NULL, " \t", &last)) == NULL ||
146 (args[3] = strtok_r(NULL, " \t", &last)) == NULL) {
147 if(args[0] != NULL) /* this would include comment lines */
148 syslog(LOG_ERR, "%s: line %d: malformed line", file, lineno);
149 continue;
150 }
151
152 l = find_limit(args[2]);
153 if(l == NULL) {
154 syslog(LOG_ERR, "%s: line %d: unknown limit %s", file, lineno, args[2]);
155 continue;
156 }
157 if(strcmp(args[3], "-") == 0) {
158 value = RLIM_INFINITY;
159 } else {
160 errno = 0;
161 value = strtol(args[3], &end, 10);
162 if(*end != '\0') {
163 syslog(LOG_ERR, "%s: line %d: bad value %s", file, lineno, args[3]);
164 continue;
165 }
166 if((value == LONG_MIN || value == LONG_MAX) && errno == ERANGE) {
167 syslog(LOG_ERR, "%s: line %d: bad value %s", file, lineno, args[3]);
168 continue;
169 }
170 if(value * l->scale < value)
171 value = RLIM_INFINITY;
172 else
173 value *= l->scale;
174 }
175 level = 0;
176 /* XXX unclear: if you set group hard and user soft limit,
177 should the hard limit still apply? this code doesn't. */
178 if(strcmp(args[0], pwd->pw_name) == 0)
179 level = 3;
180 if(*args[0] == '@') {
181 struct group *gr;
182 gr = getgrnam(args[0] + 1);
183 if(gr != NULL && gr->gr_gid == pwd->pw_gid)
184 level = 2;
185 }
186 if(strcmp(args[0], "*") == 0)
187 level = 1;
188 if(level == 0 || level < l->has_limit) /* not for us */
189 continue;
190 if(l->has_limit < level) {
191 if(getrlimit(l->resource, &l->limit) < 0)
192 continue;
193 l->has_limit = level;
194 }
195
196 /* XXX unclear: if you soft to more than default hard, should
197 we set hard to soft? this code doesn't. */
198 if(strcasecmp(args[1], "soft") == 0 || strcmp(args[1], "-") == 0)
199 l->limit.rlim_cur = value;
200 if(strcasecmp(args[1], "hard") == 0 || strcmp(args[1], "-") == 0)
201 l->limit.rlim_max = value;
202 }
203 fclose(f);
204 for(l = limits; l->name != NULL; l++) {
205 if(l->has_limit) {
206 if(l->limit.rlim_cur > l->limit.rlim_max)
207 l->limit.rlim_cur = l->limit.rlim_max;
208 if(setrlimit(l->resource, &l->limit) != 0)
209 syslog(LOG_ERR, "setrlimit RLIM_%s failed: %m", l->name);
210 }
211 l->has_limit = 0;
212 }
213 return 0;
214 }
215