2 * Copyright (c) 2005 Thorsten Kukuk <kukuk@thkukuk.de>
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, and the entire permission notice in its entirety,
9 * including the disclaimer of warranties.
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 * 3. The name of the author may not be used to endorse or promote
14 * products derived from this software without specific prior
17 * ALTERNATIVELY, this product may be distributed under the terms of
18 * the GNU Public License, in which case the provisions of the GPL are
19 * required INSTEAD OF the above restrictions. (This clause is
20 * necessary due to a potential bad interaction between the GPL and
21 * the restrictions contained in a BSD-style copyright.)
23 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
27 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
29 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
31 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
33 * OF THE POSSIBILITY OF SUCH DAMAGE.
47 #include <sys/types.h>
48 #include <sys/resource.h>
50 #define PAM_SM_SESSION
52 #include <security/pam_modules.h>
53 #include <security/_pam_modutil.h>
60 typedef struct options_t options_t;
62 /* syslogging function for errors and other information */
64 __pam_log (int err, const char *format,...)
69 va_start (args, format);
70 if (vasprintf (&str, format, args) < 0)
72 syslog (err, "pam_umask: %s", str);
77 parse_option (const char *argv, options_t *options)
79 if (argv == NULL || argv[0] == '\0')
82 if (strcasecmp (argv, "debug") == 0)
84 else if (strncasecmp (argv, "umask=", 6) == 0)
85 options->umask = strdup (&argv[6]);
86 else if (strcasecmp (argv, "usergroups") == 0)
87 options->usergroups = 1;
89 __pam_log (LOG_ERR, "Unknown option: `%s'", argv);
93 search_key (const char *filename)
100 fp = fopen (filename, "r");
107 #if defined(HAVE_GETLINE)
108 ssize_t n = getline (&buf, &buflen, fp);
109 #elif defined (HAVE_GETDELIM)
110 ssize_t n = getdelim (&buf, &buflen, '\n', fp);
117 buf = malloc (buflen);
120 fgets (buf, buflen - 1, fp);
125 #endif /* HAVE_GETLINE / HAVE_GETDELIM */
131 tmp = strchr (cp, '#'); /* remove comments */
134 while (isspace ((int)*cp)) /* remove spaces and tabs */
136 if (*cp == '\0') /* ignore empty lines */
139 if (cp[strlen (cp) - 1] == '\n')
140 cp[strlen (cp) - 1] = '\0';
142 tmp = strsep (&cp, " \t=");
144 while (isspace ((int)*cp) || *cp == '=')
147 if (strcasecmp (tmp, "UMASK") == 0)
149 retval = strdup (cp);
162 get_options (options_t *options, int argc, const char **argv)
164 memset (options, 0, sizeof (options_t));
165 /* Parse parameters for module */
166 for ( ; argc-- > 0; argv++)
167 parse_option (*argv, options);
169 if (options->umask == NULL)
170 options->umask = search_key ("/etc/login.defs");
171 if (options->umask == NULL)
172 options->umask = search_key ("/etc/default/login");
178 set_umask (const char *value)
180 const char *value_orig = value;
184 mask = strtol (value, &endptr, 8) & 0777;
185 if ((mask == 0) && (value_orig == endptr))
191 /* Set the process nice, ulimit, and umask from the
192 password file entry. */
194 setup_limits_from_gecos (pam_handle_t *pamh, options_t *options,
199 if (options->usergroups)
201 /* if not root, and UID == GID, and username is the same as
202 primary group name, set umask group bits to be the same as
203 owner bits (examples: 022 -> 002, 077 -> 007). */
204 if (pw->pw_uid != 0 && pw->pw_uid == pw->pw_gid)
206 struct group *grp = _pammodutil_getgrgid (pamh, pw->pw_gid);
207 if (grp && (strcmp (pw->pw_name, grp->gr_name) == 0))
209 mode_t oldmask = umask (0777);
210 umask ((oldmask & ~070) | ((oldmask >> 3) & 070));
215 /* See if the GECOS field contains values for NICE, UMASK or ULIMIT. */
216 for (cp = pw->pw_gecos; cp != NULL; cp = strchr (cp, ','))
221 if (strncasecmp (cp, "umask=", 6) == 0)
222 umask (strtol (cp + 6, NULL, 8) & 0777);
223 else if (strncasecmp (cp, "pri=", 4) == 0)
224 nice (strtol (cp + 4, NULL, 10));
225 else if (strncasecmp (cp, "ulimit=", 7) == 0)
227 struct rlimit rlimit_fsize;
228 rlimit_fsize.rlim_cur = 512L * strtol (cp + 7, NULL, 10);
229 rlimit_fsize.rlim_max = rlimit_fsize.rlim_cur;
230 setrlimit (RLIMIT_FSIZE, &rlimit_fsize);
237 pam_sm_open_session (pam_handle_t *pamh, int flags,
238 int argc, const char **argv)
243 int retval = PAM_SUCCESS;
245 get_options (&options, argc, argv);
247 /* get the user name. */
248 if ((retval = pam_get_user (pamh, &name, NULL)) != PAM_SUCCESS)
250 __pam_log (LOG_ERR, "pam_get_user failed: return %d", retval);
251 return (retval == PAM_CONV_AGAIN ? PAM_INCOMPLETE:retval);
254 if (name == NULL || name[0] == '\0')
258 __pam_log (LOG_ERR, "bad username [%s]", name);
259 return PAM_USER_UNKNOWN;
261 return PAM_SERVICE_ERR;
264 pw = _pammodutil_getpwnam (pamh, name);
267 __pam_log (LOG_ERR, "account for %s not found", name);
268 return PAM_USER_UNKNOWN;
271 if (options.umask != NULL)
273 set_umask (options.umask);
274 free (options.umask);
277 setup_limits_from_gecos (pamh, &options, pw);
283 pam_sm_close_session (pam_handle_t *pamh, int flags,
284 int argc, const char **argv)
291 /* static module data */
293 struct pam_module _pam_umask_modstruct = {
299 pam_sm_close_session,
305 /* end of module definition */