ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/cvsroot/libptytty/src/logging.C
Revision: 1.45
Committed: Fri Jul 8 20:56:52 2011 UTC (15 years, 2 months ago) by sf-exg
Content type: text/plain
Branch: MAIN
Changes since 1.44: +20 -21 lines
Log Message:
Generate the utmp(x) id in the same way as openssh.

File Contents

# Content
1 // This file is part of libptytty. Do not make local modifications.
2 // http://software.schmorp.de/pkg/libptytty
3
4 /*----------------------------------------------------------------------*
5 * File: logging.C
6 *----------------------------------------------------------------------*
7 *
8 * All portions of code are copyright by their respective author/s.
9 * Copyright (c) 1992 John Bovey <jdb@ukc.ac.uk>
10 * - original version
11 * Copyright (c) 1993 lipka
12 * Copyright (c) 1993 Brian Stempien <stempien@cs.wmich.edu>
13 * Copyright (c) 1995 Raul Garcia Garcia <rgg@tid.es>
14 * Copyright (c) 1995 Piet W. Plomp <piet@idefix.icce.rug.nl>
15 * Copyright (c) 1997 Raul Garcia Garcia <rgg@tid.es>
16 * Copyright (c) 1998-2001 Geoff Wing <gcw@pobox.com>
17 * - extensive modifications
18 * Copyright (c) 1999 D J Hawkey Jr <hawkeyd@visi.com>
19 * - lastlog support
20 * Copyright (c) 2004-2006 Marc Lehmann <schmorp@schmorp.de>
21 * Copyright (c) 2006 Emanuele Giaquinta <e.giaquinta@glauco.it>
22 *
23 * This program is free software; you can redistribute it and/or modify
24 * it under the terms of the GNU General Public License as published by
25 * the Free Software Foundation; either version 2 of the License, or
26 * (at your option) any later version.
27 *
28 * This program is distributed in the hope that it will be useful,
29 * but WITHOUT ANY WARRANTY; without even the implied warranty of
30 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
31 * GNU General Public License for more details.
32 *
33 * You should have received a copy of the GNU General Public License
34 * along with this program; if not, write to the Free Software
35 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
36 *----------------------------------------------------------------------*/
37
38 #include "config.h"
39
40 #include "ptytty.h"
41
42 #if UTMP_SUPPORT
43
44 #include <cstdio>
45 #include <cstring>
46
47 #include <sys/types.h>
48 #include <sys/stat.h>
49 #include <fcntl.h>
50 #include <unistd.h>
51 #include <time.h>
52 #include <errno.h>
53
54 /*
55 * BSD style utmp entry
56 * ut_line, ut_name, ut_host, ut_time
57 * SYSV style utmp (and utmpx) entry
58 * ut_user, ut_id, ut_line, ut_pid, ut_type, ut_exit, ut_time
59 */
60
61 /* ------------------------------------------------------------------------- */
62 /*
63 * Write a BSD style utmp entry
64 */
65 #if defined(HAVE_STRUCT_UTMP) && !defined(HAVE_UTMP_PID)
66 static int
67 write_bsd_utmp (int utmp_pos, struct utmp *ut)
68 {
69 int fd;
70
71 if (utmp_pos <= 0 || (fd = open (UTMP_FILE, O_WRONLY)) == -1)
72 return 0;
73
74 if (lseek (fd, (off_t) (utmp_pos * sizeof (struct utmp)), SEEK_SET) != -1)
75 write (fd, ut, sizeof (struct utmp));
76 close (fd);
77 return 1;
78 }
79 #endif
80
81 /* ------------------------------------------------------------------------- */
82 /*
83 * Update a BSD style wtmp entry
84 */
85 #if defined(WTMP_SUPPORT) && !defined(HAVE_UPDWTMP) && defined(HAVE_STRUCT_UTMP)
86 static void
87 update_wtmp (const char *fname, const struct utmp *ut)
88 {
89 int fd, gotlock, retry;
90 struct flock lck; /* fcntl locking scheme */
91 struct stat sbuf;
92
93 if ((fd = open (fname, O_WRONLY | O_APPEND, 0)) < 0)
94 return;
95
96 lck.l_whence = SEEK_END; /* start lock at current eof */
97 lck.l_len = 0; /* end at ``largest possible eof'' */
98 lck.l_start = 0;
99 lck.l_type = F_WRLCK; /* we want a write lock */
100
101 /* attempt lock with F_SETLK; F_SETLKW would cause a deadlock! */
102 for (retry = 10, gotlock = 0; retry--;)
103 if (fcntl (fd, F_SETLK, &lck) != -1)
104 {
105 gotlock = 1;
106 break;
107 }
108 else if (errno != EAGAIN && errno != EACCES)
109 break;
110 if (!gotlock)
111 {
112 /* give it up */
113 close (fd);
114 return;
115 }
116 if (fstat (fd, &sbuf) == 0)
117 if (write (fd, ut, sizeof (struct utmp)) != sizeof (struct utmp))
118 ftruncate (fd, sbuf.st_size); /* remove bad writes */
119
120 lck.l_type = F_UNLCK; /* unlocking the file */
121 fcntl (fd, F_SETLK, &lck);
122 close (fd);
123 }
124 #endif
125
126 /* ------------------------------------------------------------------------- */
127 #ifdef LASTLOG_SUPPORT
128 static void
129 update_lastlog (const char *pty, const char *host)
130 {
131 # if defined(HAVE_STRUCT_LASTLOGX) && defined(HAVE_UPDLASTLOGX)
132 struct lastlogx llx;
133 # endif
134 # ifdef HAVE_STRUCT_LASTLOG
135 int fd;
136 struct lastlog ll;
137 char lastlogfile[256];
138 struct passwd *pwent;
139 struct stat st;
140 # endif
141
142 # if defined(HAVE_STRUCT_LASTLOGX) && defined(HAVE_UPDLASTLOGX)
143 memset (&llx, 0, sizeof (llx));
144 llx.ll_tv.tv_sec = time (NULL);
145 llx.ll_tv.tv_usec = 0;
146 strncpy (llx.ll_line, pty, sizeof (llx.ll_line));
147 strncpy (llx.ll_host, host, sizeof (llx.ll_host));
148 updlastlogx (LASTLOGX_FILE, getuid (), &llx);
149 # endif
150
151 # ifdef HAVE_STRUCT_LASTLOG
152 pwent = getpwuid (getuid ());
153 if (!pwent)
154 {
155 PTYTTY_WARN ("no entry in password file, not updating lastlog.\n", 0);
156 return;
157 }
158
159 memset (&ll, 0, sizeof (ll));
160 ll.ll_time = time (NULL);
161 strncpy (ll.ll_line, pty, sizeof (ll.ll_line));
162 strncpy (ll.ll_host, host, sizeof (ll.ll_host));
163 if (stat (LASTLOG_FILE, &st) != 0)
164 return;
165 if (S_ISDIR (st.st_mode))
166 {
167 snprintf (lastlogfile, sizeof (lastlogfile), "%s/%s", LASTLOG_FILE,
168 (!pwent->pw_name || pwent->pw_name[0] == '\0') ? "unknown"
169 : pwent->pw_name);
170 if ((fd = open (lastlogfile, O_WRONLY | O_CREAT, 0644)) >= 0)
171 {
172 write (fd, &ll, sizeof (ll));
173 close (fd);
174 }
175 }
176 else if (S_ISREG (st.st_mode))
177 if ((fd = open (LASTLOG_FILE, O_RDWR)) != -1)
178 {
179 if (lseek (fd, (off_t) ((long)pwent->pw_uid * sizeof (ll)),
180 SEEK_SET) != -1)
181 write (fd, &ll, sizeof (ll));
182 close (fd);
183 }
184 # endif /* HAVE_STRUCT_LASTLOG */
185 }
186 #endif /* LASTLOG_SUPPORT */
187
188 #if defined(HAVE_UTMP_PID) || defined(HAVE_STRUCT_UTMPX)
189 static void
190 fill_id (char *id, const char *line, size_t id_size)
191 {
192 size_t len = strlen (line);
193
194 if (len > id_size)
195 line += len - id_size;
196 strncpy (id, line, id_size);
197 }
198 #endif
199
200 #ifdef HAVE_STRUCT_UTMP
201 static void
202 fill_utmp (struct utmp *ut, bool login, int pid, const char *line, const char *user, const char *host)
203 {
204 memset (ut, 0, sizeof (struct utmp));
205
206 strncpy (ut->ut_line, line, sizeof (ut->ut_line));
207 # ifdef HAVE_UTMP_PID
208 fill_id (ut->ut_id, line, sizeof (ut->ut_id));
209 ut->ut_pid = pid;
210 ut->ut_type = login ? USER_PROCESS : DEAD_PROCESS;
211 # endif
212 ut->ut_time = time (NULL);
213
214 if (login)
215 {
216 # ifdef HAVE_UTMP_PID
217 strncpy (ut->ut_user, user, sizeof (ut->ut_user));
218 # else
219 strncpy (ut->ut_name, user, sizeof (ut->ut_name));
220 # endif
221 # ifdef HAVE_UTMP_HOST
222 strncpy (ut->ut_host, host, sizeof (ut->ut_host));
223 # endif
224 }
225 }
226 #endif
227
228 #ifdef HAVE_STRUCT_UTMPX
229 static void
230 fill_utmpx (struct utmpx *utx, bool login, int pid, const char *line, const char *user, const char *host)
231 {
232 memset (utx, 0, sizeof (struct utmpx));
233
234 // posix says that ut_line is not meaningful for DEAD_PROCESS
235 // records, but most implementations of last use ut_line to
236 // associate records in wtmp file
237 strncpy (utx->ut_line, line, sizeof (utx->ut_line));
238 fill_id (utx->ut_id, line, sizeof (utx->ut_id));
239 utx->ut_pid = pid;
240 utx->ut_type = login ? USER_PROCESS : DEAD_PROCESS;
241 utx->ut_tv.tv_sec = time (NULL);
242 utx->ut_tv.tv_usec = 0;
243 # if HAVE_UTMPX_SESSION
244 utx->ut_session = getsid (0);
245 # endif
246
247 if (login)
248 {
249 strncpy (utx->ut_user, user, sizeof (utx->ut_user));
250 # ifdef HAVE_UTMPX_HOST
251 strncpy (utx->ut_host, host, sizeof (utx->ut_host));
252 # endif
253 }
254 }
255 #endif
256
257 /* ------------------------------------------------------------------------- */
258
259 /*
260 * make and write utmp and wtmp entries
261 */
262 void
263 ptytty_unix::login (int cmd_pid, bool login_shell, const char *hostname)
264 {
265 const char *pty = name;
266
267 if (!pty || !*pty)
268 return;
269
270 this->cmd_pid = cmd_pid;
271 this->login_shell = login_shell;
272
273 #ifdef HAVE_STRUCT_UTMP
274 struct utmp *ut = &this->ut;
275 #endif
276 #ifdef HAVE_STRUCT_UTMPX
277 struct utmpx *utx = &this->utx;
278 #endif
279 struct passwd *pwent = getpwuid (getuid ());
280 const char *user = (pwent && pwent->pw_name) ? pwent->pw_name : "?";
281
282 if (!strncmp (pty, "/dev/", 5))
283 pty += 5; /* skip /dev/ prefix */
284
285 #ifdef HAVE_STRUCT_UTMP
286 fill_utmp (ut, true, cmd_pid, pty, user, hostname);
287 #endif
288
289 #ifdef HAVE_STRUCT_UTMPX
290 fill_utmpx (utx, true, cmd_pid, pty, user, hostname);
291 #endif
292
293 #ifdef HAVE_STRUCT_UTMP
294 # ifdef HAVE_UTMP_PID
295 setutent ();
296 pututline (ut);
297 endutent ();
298 # else
299 int fd_stdin = dup (STDIN_FILENO);
300 dup2 (tty, STDIN_FILENO);
301
302 utmp_pos = ttyslot ();
303 if (!write_bsd_utmp (utmp_pos, ut))
304 utmp_pos = 0;
305
306 dup2 (fd_stdin, STDIN_FILENO);
307 close (fd_stdin);
308 # endif
309 #endif
310
311 #ifdef HAVE_STRUCT_UTMPX
312 setutxent ();
313 pututxline (utx);
314 endutxent ();
315 #endif
316
317 #ifdef WTMP_SUPPORT
318 #ifdef LOG_ONLY_ON_LOGIN
319 if (login_shell)
320 #endif
321 {
322 # ifdef HAVE_STRUCT_UTMP
323 # ifdef HAVE_UPDWTMP
324 updwtmp (WTMP_FILE, ut);
325 # else
326 update_wtmp (WTMP_FILE, ut);
327 # endif
328 # endif
329 # if defined(HAVE_STRUCT_UTMPX) && defined(HAVE_UPDWTMPX)
330 updwtmpx (WTMPX_FILE, utx);
331 # endif
332 }
333 #endif
334 #ifdef LASTLOG_SUPPORT
335 #ifdef LOG_ONLY_ON_LOGIN
336 if (login_shell)
337 #endif
338 update_lastlog (pty, hostname);
339 #endif
340 }
341
342 /* ------------------------------------------------------------------------- */
343 /*
344 * remove utmp and wtmp entries
345 */
346 void
347 ptytty_unix::logout ()
348 {
349 if (!cmd_pid)
350 return;
351
352 const char *pty = name;
353
354 if (!strncmp (pty, "/dev/", 5))
355 pty += 5;
356
357 #ifdef HAVE_STRUCT_UTMP
358 struct utmp *tmput, *ut = &this->ut;
359 #endif
360 #ifdef HAVE_STRUCT_UTMPX
361 struct utmpx *tmputx, *utx = &this->utx;
362 #endif
363
364 #ifdef HAVE_STRUCT_UTMP
365 fill_utmp (ut, false, cmd_pid, pty, 0, 0);
366 #endif
367
368 #ifdef HAVE_STRUCT_UTMPX
369 fill_utmpx (utx, false, cmd_pid, pty, 0, 0);
370 #endif
371
372 /*
373 * Write ending wtmp entry
374 */
375 #ifdef WTMP_SUPPORT
376 #ifdef LOG_ONLY_ON_LOGIN
377 if (login_shell)
378 #endif
379 {
380 # ifdef HAVE_STRUCT_UTMP
381 # ifdef HAVE_UPDWTMP
382 updwtmp (WTMP_FILE, ut);
383 # else
384 update_wtmp (WTMP_FILE, ut);
385 # endif
386 # endif
387 # if defined(HAVE_STRUCT_UTMPX) && defined(HAVE_UPDWTMPX)
388 updwtmpx (WTMPX_FILE, utx);
389 # endif
390 }
391 #endif
392
393 /*
394 * Write utmp entry
395 */
396 #ifdef HAVE_STRUCT_UTMP
397 # ifdef HAVE_UTMP_PID
398 setutent ();
399 tmput = getutid (ut);
400 if (tmput && tmput->ut_pid == cmd_pid)
401 pututline (ut);
402 endutent ();
403 # else
404 write_bsd_utmp (utmp_pos, ut);
405 # endif
406 #endif
407 #ifdef HAVE_STRUCT_UTMPX
408 setutxent ();
409 tmputx = getutxid (utx);
410 if (tmputx && tmputx->ut_pid == cmd_pid)
411 pututxline (utx);
412 endutxent ();
413 #endif
414
415 cmd_pid = 0;
416 }
417
418 #else
419 void
420 ptytty_unix::login (int cmd_pid, bool login_shell, const char *hostname)
421 {
422 }
423 #endif
424