2 * Copyright (c) 2011 Todd C. Miller <Todd.Miller@courtesan.com>
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 #include <sys/types.h>
20 #include <sys/param.h>
31 #endif /* STDC_HEADERS */
33 # if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
37 #endif /* HAVE_STRING_H */
40 #endif /* HAVE_STRINGS_H */
43 #endif /* HAVE_UNISTD_H */
44 #if TIME_WITH_SYS_TIME
51 #endif /* HAVE_UTMPX_H */
58 #include "sudo_exec.h"
61 * Simplify handling of utmp vs. utmpx
63 #if !defined(HAVE_GETUTXID) && defined(HAVE_GETUTID)
64 # define getutxline(u) getutline(u)
65 # define pututxline(u) pututline(u)
66 # define setutxent setutent(u)
67 # define endutxent endutent(u)
68 #endif /* !HAVE_GETUTXID && HAVE_GETUTID */
71 typedef struct utmpx sudo_utmp_t;
73 typedef struct utmp sudo_utmp_t;
74 /* Older systems have ut_name, not us_user */
75 # if !defined(HAVE_STRUCT_UTMP_UT_USER) && !defined(ut_user)
76 # define ut_user ut_name
80 /* HP-UX has __e_termination and __e_exit, others lack the __ */
81 #if defined(HAVE_STRUCT_UTMPX_UT_EXIT_E_TERMINATION) || defined(HAVE_STRUCT_UTMP_UT_EXIT_E_TERMINATION)
82 # undef __e_termination
83 # define __e_termination e_termination
85 # define __e_exit e_exit
88 #if defined(HAVE_GETUTXID) || defined(HAVE_GETUTID)
90 * Create ut_id from the new ut_line and the old ut_id.
93 utmp_setid(sudo_utmp_t *old, sudo_utmp_t *new)
95 const char *line = new->ut_line;
98 /* Skip over "tty" in the id if old entry did too. */
100 if (strncmp(line, "tty", 3) == 0) {
101 idlen = MIN(sizeof(old->ut_id), 3);
102 if (strncmp(old->ut_id, "tty", idlen) != 0)
107 /* Store as much as will fit, skipping parts of the beginning as needed. */
108 idlen = strlen(line);
109 if (idlen > sizeof(new->ut_id)) {
110 line += idlen - sizeof(new->ut_id);
111 idlen = sizeof(new->ut_id);
113 strncpy(new->ut_id, line, idlen);
115 #endif /* HAVE_GETUTXID || HAVE_GETUTID */
118 * Store time in utmp structure.
121 utmp_settime(sudo_utmp_t *ut)
125 gettimeofday(&tv, NULL);
127 #if defined(HAVE_STRUCT_UTMP_UT_TV) || defined(HAVE_STRUCT_UTMPX_UT_TV)
128 ut->ut_tv.tv_sec = tv.tv_sec;
129 ut->ut_tv.tv_usec = tv.tv_usec;
131 ut->ut_time = tv.tv_sec;
136 * Fill in a utmp entry, using an old entry as a template if there is one.
139 utmp_fill(const char *line, const char *user, sudo_utmp_t *ut_old,
142 if (ut_old == NULL) {
143 memset(ut_new, 0, sizeof(*ut_new));
145 strncpy(ut_new->ut_user, user_details.username,
146 sizeof(ut_new->ut_user));
148 } else if (ut_old != ut_new) {
149 memcpy(ut_new, ut_old, sizeof(*ut_new));
152 strncpy(ut_new->ut_user, user, sizeof(ut_new->ut_user));
153 strncpy(ut_new->ut_line, line, sizeof(ut_new->ut_line));
154 #if defined(HAVE_STRUCT_UTMPX_UT_ID) || defined(HAVE_STRUCT_UTMP_UT_ID)
155 utmp_setid(ut_old, ut_new);
157 #if defined(HAVE_STRUCT_UTMPX_UT_PID) || defined(HAVE_STRUCT_UTMP_UT_PID)
158 ut_new->ut_pid = getpid();
160 utmp_settime(ut_new);
161 #if defined(HAVE_STRUCT_UTMPX_UT_TYPE) || defined(HAVE_STRUCT_UTMP_UT_TYPE)
162 ut_new->ut_type = USER_PROCESS;
167 * There are two basic utmp file types:
169 * POSIX: sequential access with new entries appended to the end.
170 * Manipulated via {get,put}utent()/{get,put}getutxent().
172 * Legacy: sparse file indexed by ttyslot() * sizeof(struct utmp)
174 #if defined(HAVE_GETUTXID) || defined(HAVE_GETUTID)
176 utmp_login(const char *from_line, const char *to_line, int ttyfd,
179 sudo_utmp_t utbuf, *ut_old = NULL;
182 /* Strip off /dev/ prefix from line as needed. */
183 if (strncmp(to_line, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
184 to_line += sizeof(_PATH_DEV) - 1;
186 if (from_line != NULL) {
187 if (strncmp(from_line, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
188 from_line += sizeof(_PATH_DEV) - 1;
190 /* Lookup old line. */
191 memset(&utbuf, 0, sizeof(utbuf));
192 strncpy(utbuf.ut_line, from_line, sizeof(utbuf.ut_line));
193 ut_old = getutxline(&utbuf);
195 utmp_fill(to_line, user, ut_old, &utbuf);
196 if (pututxline(&utbuf) != NULL)
204 utmp_logout(const char *line, int status)
207 sudo_utmp_t *ut, utbuf;
209 /* Strip off /dev/ prefix from line as needed. */
210 if (strncmp(line, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
211 line += sizeof(_PATH_DEV) - 1;
213 memset(&utbuf, 0, sizeof(utbuf));
214 strncpy(utbuf.ut_line, line, sizeof(utbuf.ut_line));
215 if ((ut = getutxline(&utbuf)) != NULL) {
216 memset(ut->ut_user, 0, sizeof(ut->ut_user));
217 # if defined(HAVE_STRUCT_UTMPX_UT_TYPE) || defined(HAVE_STRUCT_UTMP_UT_TYPE)
218 ut->ut_type = DEAD_PROCESS;
220 # if defined(HAVE_STRUCT_UTMPX_UT_EXIT) || defined(HAVE_STRUCT_UTMP_UT_EXIT)
221 ut->ut_exit.__e_exit = WEXITSTATUS(status);
222 ut->ut_exit.__e_termination = WIFEXITED(status) ? WEXITSTATUS(status) : 0;
225 if (pututxline(ut) != NULL)
231 #else /* !HAVE_GETUTXID && !HAVE_GETUTID */
234 * Find the slot for the specified line (tty name and file descriptor).
235 * Returns a slot suitable for seeking into utmp on success or <= 0 on error.
236 * If getttyent() is available we can use that to compute the slot.
238 # ifdef HAVE_GETTTYENT
240 utmp_slot(const char *line, int ttyfd)
246 while ((tty = getttyent()) != NULL) {
247 if (strcmp(line, tty->ty_name) == 0)
252 return tty ? slot : 0;
256 utmp_slot(const char *line, int ttyfd)
261 * Temporarily point stdin to the tty since ttyslot()
262 * doesn't take an argument.
264 if ((sfd = dup(STDIN_FILENO)) == -1)
265 error(1, _("unable to save stdin"));
266 if (dup2(ttyfd, STDIN_FILENO) == -1)
267 error(1, _("unable to dup2 stdin"));
269 if (dup2(sfd, STDIN_FILENO) == -1)
270 error(1, _("unable to restore stdin"));
275 # endif /* HAVE_GETTTYENT */
278 utmp_login(const char *from_line, const char *to_line, int ttyfd,
281 sudo_utmp_t utbuf, *ut_old = NULL;
282 int slot, rval = FALSE;
285 /* Strip off /dev/ prefix from line as needed. */
286 if (strncmp(to_line, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
287 to_line += sizeof(_PATH_DEV) - 1;
289 /* Find slot for new entry. */
290 slot = utmp_slot(to_line, ttyfd);
294 if ((fp = fopen(_PATH_UTMP, "r+")) == NULL)
297 if (from_line != NULL) {
298 if (strncmp(from_line, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
299 from_line += sizeof(_PATH_DEV) - 1;
301 /* Lookup old line. */
302 while (fread(&utbuf, sizeof(utbuf), 1, fp) == 1) {
303 # ifdef HAVE_STRUCT_UTMP_UT_ID
304 if (utbuf.ut_type != LOGIN_PROCESS && utbuf.ut_type != USER_PROCESS)
307 if (utbuf.ut_user[0] &&
308 !strncmp(utbuf.ut_line, from_line, sizeof(utbuf.ut_line))) {
314 utmp_fill(to_line, user, ut_old, &utbuf);
315 if (fseek(fp, slot * (long)sizeof(utbuf), SEEK_SET) == 0) {
316 if (fwrite(&utbuf, sizeof(utbuf), 1, fp) == 1)
326 utmp_logout(const char *line, int status)
332 if ((fp = fopen(_PATH_UTMP, "r+")) == NULL)
335 /* Strip off /dev/ prefix from line as needed. */
336 if (strncmp(line, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
337 line += sizeof(_PATH_DEV) - 1;
339 while (fread(&utbuf, sizeof(utbuf), 1, fp) == 1) {
340 if (!strncmp(utbuf.ut_line, line, sizeof(utbuf.ut_line))) {
341 memset(utbuf.ut_user, 0, sizeof(utbuf.ut_user));
342 # if defined(HAVE_STRUCT_UTMP_UT_TYPE)
343 utbuf.ut_type = DEAD_PROCESS;
345 utmp_settime(&utbuf);
346 /* Back up and overwrite record. */
347 if (fseek(fp, 0L - (long)sizeof(utbuf), SEEK_CUR) == 0) {
348 if (fwrite(&utbuf, sizeof(utbuf), 1, fp) == 1)
358 #endif /* HAVE_GETUTXID || HAVE_GETUTID */