2 * Copyright (c) 1996 by
3 * Sean Eric Fagan <sef@kithrup.com>
4 * David Nugent <davidn@blaze.net.au>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, is permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice immediately at the beginning of the file, without modification,
12 * this list of conditions, and the following disclaimer.
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 * 3. This work was done expressly for inclusion into FreeBSD. Other use
17 * is permitted provided this notation is included.
18 * 4. Absolutely no warranty of function or purpose is made by the authors.
19 * 5. Modifications may be freely made to this file providing the above
22 * High-level routines relating to use of the user capabilities database
25 #include <sys/cdefs.h>
26 __FBSDID("$FreeBSD$");
28 #include <sys/types.h>
31 #include <sys/resource.h>
33 #include <sys/rtprio.h>
36 #include <login_cap.h>
46 static struct login_res {
48 rlim_t (*who)(login_cap_t *, const char *, rlim_t, rlim_t);
51 { "cputime", login_getcaptime, RLIMIT_CPU },
52 { "filesize", login_getcapsize, RLIMIT_FSIZE },
53 { "datasize", login_getcapsize, RLIMIT_DATA },
54 { "stacksize", login_getcapsize, RLIMIT_STACK },
55 { "memoryuse", login_getcapsize, RLIMIT_RSS },
56 { "memorylocked", login_getcapsize, RLIMIT_MEMLOCK },
57 { "maxproc", login_getcapnum, RLIMIT_NPROC },
58 { "openfiles", login_getcapnum, RLIMIT_NOFILE },
59 { "coredumpsize", login_getcapsize, RLIMIT_CORE },
60 { "sbsize", login_getcapsize, RLIMIT_SBSIZE },
61 { "vmemoryuse", login_getcapsize, RLIMIT_VMEM },
67 setclassresources(login_cap_t *lc)
74 for (lr = resources; lr->what != NULL; ++lr) {
78 * The login.conf file can have <limit>, <limit>-max, and
79 * <limit>-cur entries.
80 * What we do is get the current current- and maximum- limits.
81 * Then, we try to get an entry for <limit> from the capability,
82 * using the current and max limits we just got as the
83 * default/error values.
84 * *Then*, we try looking for <limit>-cur and <limit>-max,
85 * again using the appropriate values as the default/error
89 if (getrlimit(lr->why, &rlim) != 0)
90 syslog(LOG_ERR, "getting %s resource limit: %m", lr->what);
94 rlim_t rcur = rlim.rlim_cur;
95 rlim_t rmax = rlim.rlim_max;
97 sprintf(name_cur, "%s-cur", lr->what);
98 sprintf(name_max, "%s-max", lr->what);
100 rcur = (*lr->who)(lc, lr->what, rcur, rcur);
101 rmax = (*lr->who)(lc, lr->what, rmax, rmax);
102 rlim.rlim_cur = (*lr->who)(lc, name_cur, rcur, rcur);
103 rlim.rlim_max = (*lr->who)(lc, name_max, rmax, rmax);
105 if (setrlimit(lr->why, &rlim) == -1)
106 syslog(LOG_WARNING, "set class '%s' resource limit %s: %m", lc->lc_class, lr->what);
113 static struct login_vars {
119 { "path", "PATH", NULL, 1},
120 { "cdpath", "CDPATH", NULL, 1},
121 { "manpath", "MANPATH", NULL, 1},
122 { NULL, NULL, NULL, 0}
124 { "lang", "LANG", NULL, 1},
125 { "charset", "MM_CHARSET", NULL, 1},
126 { "timezone", "TZ", NULL, 1},
127 { "term", "TERM", NULL, 0},
128 { NULL, NULL, NULL, 0}
132 substvar(const char * var, const struct passwd * pwd, int hlen, int pch, int nlen)
142 /* Count the number of ~'s in var to substitute */
143 for (p = (char *)var; (p = strchr(p, '~')) != NULL; p++)
145 /* Count the number of $'s in var to substitute */
146 for (p = (char *)var; (p = strchr(p, '$')) != NULL; p++)
150 np = malloc(strlen(var) + (dollas * nlen)
151 - dollas + (tildes * (pch+hlen))
159 * This loop does user username and homedir substitutions
160 * for unescaped $ (username) and ~ (homedir)
162 while (*(p += strcspn(p, "~$")) != '\0') {
165 if (p > np && *(p-1) == '\\') /* Escaped: */
166 memmove(p - 1, p, l + 1); /* Slide-out the backslash */
167 else if (*p == '~') {
168 int v = pch && *(p+1) != '/'; /* Avoid double // */
169 memmove(p + hlen + v, p + 1, l); /* Subst homedir */
170 memmove(p, pwd->pw_dir, hlen);
175 else /* if (*p == '$') */ {
176 memmove(p + nlen, p + 1, l); /* Subst username */
177 memmove(p, pwd->pw_name, nlen);
190 setclassenvironment(login_cap_t *lc, const struct passwd * pwd, int paths)
192 struct login_vars *vars = paths ? pathvars : envars;
193 int hlen = pwd ? strlen(pwd->pw_dir) : 0;
194 int nlen = pwd ? strlen(pwd->pw_name) : 0;
197 if (hlen && pwd->pw_dir[hlen-1] != '/')
200 while (vars->tag != NULL) {
201 const char * var = paths ? login_getpath(lc, vars->tag, NULL)
202 : login_getcapstr(lc, vars->tag, NULL, NULL);
204 char * np = substvar(var, pwd, hlen, pch, nlen);
207 setenv(vars->var, np, vars->overwrite);
209 } else if (vars->def != NULL) {
210 setenv(vars->var, vars->def, 0);
216 * If we're not processing paths, then see if there is a setenv list by
217 * which the admin and/or user may set an arbitrary set of env vars.
220 const char **set_env = login_getcaplist(lc, "setenv", ",");
222 if (set_env != NULL) {
223 while (*set_env != NULL) {
224 char *p = strchr(*set_env, '=');
226 if (p != NULL) { /* Discard invalid entries */
230 if ((np = substvar(p, pwd, hlen, pch, nlen)) != NULL) {
231 setenv(*set_env, np, 1);
245 * For the login class <class>, set various class context values
246 * (limits, mainly) to the values for that class. Which values are
247 * set are controlled by <flags> -- see <login_class.h> for the
250 * setclasscontext() can only set resources, priority, and umask.
254 setclasscontext(const char *classname, unsigned int flags)
259 lc = login_getclassbyname(classname, NULL);
261 flags &= LOGIN_SETRESOURCES | LOGIN_SETPRIORITY |
262 LOGIN_SETUMASK | LOGIN_SETPATH;
264 rc = lc ? setusercontext(lc, NULL, 0, flags) : -1;
272 * Private function which takes care of processing
276 setlogincontext(login_cap_t *lc, const struct passwd *pwd,
277 mode_t mymask, unsigned long flags)
281 if (flags & LOGIN_SETRESOURCES)
282 setclassresources(lc);
283 /* See if there's a umask override */
284 if (flags & LOGIN_SETUMASK)
285 mymask = (mode_t)login_getcapnum(lc, "umask", mymask, mymask);
287 if (flags & LOGIN_SETPATH)
288 setclassenvironment(lc, pwd, 1);
289 /* Set environment */
290 if (flags & LOGIN_SETENV)
291 setclassenvironment(lc, pwd, 0);
301 * Given a login class <lc> and a user in <pwd>, with a uid <uid>,
302 * set the context as in setclasscontext(). <flags> controls which
305 * The difference between setclasscontext() and setusercontext() is
306 * that the former sets things up for an already-existing process,
307 * while the latter sets things up from a root context. Such as might
308 * be called from login(1).
313 setusercontext(login_cap_t *lc, const struct passwd *pwd, uid_t uid, unsigned int flags)
317 login_cap_t *llc = NULL;
322 if (pwd != NULL && (lc = login_getpwclass(pwd)) != NULL)
323 llc = lc; /* free this when we're done */
326 if (flags & LOGIN_SETPATH)
327 pathvars[0].def = uid ? _PATH_DEFPATH : _PATH_STDPATH;
329 /* we need a passwd entry to set these */
331 flags &= ~(LOGIN_SETGROUP | LOGIN_SETLOGIN | LOGIN_SETMAC);
333 /* Set the process priority */
334 if (flags & LOGIN_SETPRIORITY) {
335 p = login_getcapnum(lc, "priority", LOGIN_DEFPRI, LOGIN_DEFPRI);
338 rtp.type = RTP_PRIO_IDLE;
339 rtp.prio = p - PRIO_MAX - 1;
340 p = (rtp.prio > RTP_PRIO_MAX) ? 31 : p;
341 if (rtprio(RTP_SET, 0, &rtp))
342 syslog(LOG_WARNING, "rtprio '%s' (%s): %m",
343 pwd->pw_name, lc ? lc->lc_class : LOGIN_DEFCLASS);
344 } else if (p < PRIO_MIN) {
345 rtp.type = RTP_PRIO_REALTIME;
346 rtp.prio = abs(p - PRIO_MIN + RTP_PRIO_MAX);
347 p = (rtp.prio > RTP_PRIO_MAX) ? 1 : p;
348 if (rtprio(RTP_SET, 0, &rtp))
349 syslog(LOG_WARNING, "rtprio '%s' (%s): %m",
350 pwd->pw_name, lc ? lc->lc_class : LOGIN_DEFCLASS);
352 if (setpriority(PRIO_PROCESS, 0, (int)p) != 0)
353 syslog(LOG_WARNING, "setpriority '%s' (%s): %m",
354 pwd->pw_name, lc ? lc->lc_class : LOGIN_DEFCLASS);
358 /* Setup the user's group permissions */
359 if (flags & LOGIN_SETGROUP) {
360 if (setgid(pwd->pw_gid) != 0) {
361 syslog(LOG_ERR, "setgid(%lu): %m", (u_long)pwd->pw_gid);
365 if (initgroups(pwd->pw_name, pwd->pw_gid) == -1) {
366 syslog(LOG_ERR, "initgroups(%s,%lu): %m", pwd->pw_name,
367 (u_long)pwd->pw_gid);
373 /* Set up the user's MAC label. */
374 if ((flags & LOGIN_SETMAC) && mac_is_present(NULL) == 1) {
375 const char *label_string;
378 label_string = login_getcapstr(lc, "label", NULL, NULL);
379 if (label_string != NULL) {
380 if (mac_from_text(&label, label_string) == -1) {
381 syslog(LOG_ERR, "mac_from_text('%s') for %s: %m",
382 pwd->pw_name, label_string);
385 if (mac_set_proc(label) == -1)
391 syslog(LOG_ERR, "mac_set_proc('%s') for %s: %s",
392 label_string, pwd->pw_name, strerror(error));
398 /* Set the sessions login */
399 if ((flags & LOGIN_SETLOGIN) && setlogin(pwd->pw_name) != 0) {
400 syslog(LOG_ERR, "setlogin(%s): %m", pwd->pw_name);
405 mymask = (flags & LOGIN_SETUMASK) ? umask(LOGIN_DEFUMASK) : 0;
406 mymask = setlogincontext(lc, pwd, mymask, flags);
409 /* This needs to be done after anything that needs root privs */
410 if ((flags & LOGIN_SETUSER) && setuid(uid) != 0) {
411 syslog(LOG_ERR, "setuid(%lu): %m", (u_long)uid);
412 return -1; /* Paranoia again */
416 * Now, we repeat some of the above for the user's private entries
418 if ((lc = login_getuserclass(pwd)) != NULL) {
419 mymask = setlogincontext(lc, pwd, mymask, flags);
423 /* Finally, set any umask we've found */
424 if (flags & LOGIN_SETUMASK)