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
36RCSID("$Id$");
37
38#include <errno.h>
39#include <limits.h>
40#ifdef HAVE_SYS_RESOURCE_H
41#include <sys/resource.h>
42#endif
43
44struct 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
81static struct limit *
82find_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
99int
100read_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