source: branches/samba-3.0/source/smbd/utmp.c

Last change on this file was 134, checked in by Paul Smedley, 17 years ago

Update source to 3.0.29
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[134]1/*
2 Unix SMB/CIFS implementation.
3 utmp routines
4 Copyright (C) T.D.Lee@durham.ac.uk 1999
5 Heavily modified by Andrew Bartlett and Tridge, April 2001
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20*/
21
22#include "includes.h"
23
24/****************************************************************************
25Reflect connection status in utmp/wtmp files.
26 T.D.Lee@durham.ac.uk September 1999
27
28 With grateful thanks since then to many who have helped port it to
29 different operating systems. The variety of OS quirks thereby
30 uncovered is amazing...
31
32Hints for porting:
33 o Always attempt to use programmatic interface (pututline() etc.)
34 Indeed, at present only programmatic use is supported.
35 o The only currently supported programmatic interface to "wtmp{,x}"
36 is through "updwtmp*()" routines.
37 o The "x" (utmpx/wtmpx; HAVE_UTMPX_H) seems preferable.
38 o The HAVE_* items should identify supported features.
39 o If at all possible, avoid "if defined(MY-OS)" constructions.
40
41OS observations and status:
42 Almost every OS seems to have its own quirks.
43
44 Solaris 2.x:
45 Tested on 2.6 and 2.7; should be OK on other flavours.
46 AIX:
47 Apparently has utmpx.h but doesn't implement.
48 OSF:
49 Has utmpx.h, but (e.g.) no "getutmpx()". (Is this like AIX ?)
50 Redhat 6:
51 utmpx.h seems not to set default filenames. non-x better.
52 IRIX 6.5:
53 Not tested. Appears to have "x".
54 HP-UX 9.x:
55 Not tested. Appears to lack "x".
56 HP-UX 10.x:
57 Not tested.
58 "updwtmp*()" routines seem absent, so no current wtmp* support.
59 Has "ut_addr": probably trivial to implement (although remember
60 that IPv6 is coming...).
61
62 FreeBSD:
63 No "putut*()" type of interface.
64 No "ut_type" and associated defines.
65 Write files directly. Alternatively use its login(3)/logout(3).
66 SunOS 4:
67 Not tested. Resembles FreeBSD, but no login()/logout().
68
69lastlog:
70 Should "lastlog" files, if any, be updated?
71 BSD systems (SunOS 4, FreeBSD):
72 o Prominent mention on man pages.
73 System-V (e.g. Solaris 2):
74 o No mention on man pages, even under "man -k".
75 o Has a "/var/adm/lastlog" file, but pututxline() etc. seem
76 not to touch it.
77 o Despite downplaying (above), nevertheless has <lastlog.h>.
78 So perhaps UN*X "lastlog" facility is intended for tty/terminal only?
79
80Notes:
81 Each connection requires a small number (starting at 0, working up)
82 to represent the line. This must be unique within and across all
83 smbd processes. It is the 'id_num' from Samba's session.c code.
84
85 The 4 byte 'ut_id' component is vital to distinguish connections,
86 of which there could be several hundred or even thousand.
87 Entries seem to be printable characters, with optional NULL pads.
88
89 We need to be distinct from other entries in utmp/wtmp.
90
91 Observed things: therefore avoid them. Add to this list please.
92 From Solaris 2.x (because that's what I have):
93 'sN' : run-levels; N: [0-9]
94 'co' : console
95 'CC' : arbitrary things; C: [a-z]
96 'rXNN' : rlogin; N: [0-9]; X: [0-9a-z]
97 'tXNN' : rlogin; N: [0-9]; X: [0-9a-z]
98 '/NNN' : Solaris CDE
99 'ftpZ' : ftp (Z is the number 255, aka 0377, aka 0xff)
100 Mostly a record uses the same 'ut_id' in both "utmp" and "wtmp",
101 but differences have been seen.
102
103 Arbitrarily I have chosen to use a distinctive 'SM' for the
104 first two bytes.
105
106 The remaining two bytes encode the session 'id_num' (see above).
107 Our caller (session.c) should note our 16-bit limitation.
108
109****************************************************************************/
110
111#ifndef WITH_UTMP
112/*
113 * Not WITH_UTMP? Simply supply dummy routines.
114 */
115
116void sys_utmp_claim(const char *username, const char *hostname,
117 struct in_addr *ipaddr,
118 const char *id_str, int id_num)
119{}
120
121void sys_utmp_yield(const char *username, const char *hostname,
122 struct in_addr *ipaddr,
123 const char *id_str, int id_num)
124{}
125
126#else /* WITH_UTMP */
127
128#include <utmp.h>
129
130#ifdef HAVE_UTMPX_H
131#include <utmpx.h>
132#endif
133
134/* BSD systems: some may need lastlog.h (SunOS 4), some may not (FreeBSD) */
135/* Some System-V systems (e.g. Solaris 2) declare this too. */
136#ifdef HAVE_LASTLOG_H
137#include <lastlog.h>
138#endif
139
140/****************************************************************************
141 Default paths to various {u,w}tmp{,x} files.
142****************************************************************************/
143
144#ifdef HAVE_UTMPX_H
145
146static const char *ux_pathname =
147# if defined (UTMPX_FILE)
148 UTMPX_FILE ;
149# elif defined (_UTMPX_FILE)
150 _UTMPX_FILE ;
151# elif defined (_PATH_UTMPX)
152 _PATH_UTMPX ;
153# else
154 "" ;
155# endif
156
157static const char *wx_pathname =
158# if defined (WTMPX_FILE)
159 WTMPX_FILE ;
160# elif defined (_WTMPX_FILE)
161 _WTMPX_FILE ;
162# elif defined (_PATH_WTMPX)
163 _PATH_WTMPX ;
164# else
165 "" ;
166# endif
167
168#endif /* HAVE_UTMPX_H */
169
170static const char *ut_pathname =
171# if defined (UTMP_FILE)
172 UTMP_FILE ;
173# elif defined (_UTMP_FILE)
174 _UTMP_FILE ;
175# elif defined (_PATH_UTMP)
176 _PATH_UTMP ;
177# else
178 "" ;
179# endif
180
181static const char *wt_pathname =
182# if defined (WTMP_FILE)
183 WTMP_FILE ;
184# elif defined (_WTMP_FILE)
185 _WTMP_FILE ;
186# elif defined (_PATH_WTMP)
187 _PATH_WTMP ;
188# else
189 "" ;
190# endif
191
192/* BSD-like systems might want "lastlog" support. */
193/* *** Not yet implemented */
194#ifndef HAVE_PUTUTLINE /* see "pututline_my()" */
195static const char *ll_pathname =
196# if defined (_PATH_LASTLOG) /* what other names (if any?) */
197 _PATH_LASTLOG ;
198# else
199 "" ;
200# endif /* _PATH_LASTLOG */
201#endif /* HAVE_PUTUTLINE */
202
203/*
204 * Get name of {u,w}tmp{,x} file.
205 * return: fname contains filename
206 * Possibly empty if this code not yet ported to this system.
207 *
208 * utmp{,x}: try "utmp dir", then default (a define)
209 * wtmp{,x}: try "wtmp dir", then "utmp dir", then default (a define)
210 */
211static void uw_pathname(pstring fname, const char *uw_name, const char *uw_default)
212{
213 pstring dirname;
214
215 pstrcpy(dirname, "");
216
217 /* For w-files, first look for explicit "wtmp dir" */
218 if (uw_name[0] == 'w') {
219 pstrcpy(dirname,lp_wtmpdir());
220 trim_char(dirname,'\0','/');
221 }
222
223 /* For u-files and non-explicit w-dir, look for "utmp dir" */
224 if (strlen(dirname) == 0) {
225 pstrcpy(dirname,lp_utmpdir());
226 trim_char(dirname,'\0','/');
227 }
228
229 /* If explicit directory above, use it */
230 if (strlen(dirname) != 0) {
231 pstrcpy(fname, dirname);
232 pstrcat(fname, "/");
233 pstrcat(fname, uw_name);
234 return;
235 }
236
237 /* No explicit directory: attempt to use default paths */
238 if (strlen(uw_default) == 0) {
239 /* No explicit setting, no known default.
240 * Has it yet been ported to this OS?
241 */
242 DEBUG(2,("uw_pathname: unable to determine pathname\n"));
243 }
244 pstrcpy(fname, uw_default);
245}
246
247#ifndef HAVE_PUTUTLINE
248
249/****************************************************************************
250 Update utmp file directly. No subroutine interface: probably a BSD system.
251****************************************************************************/
252
253static void pututline_my(pstring uname, struct utmp *u, BOOL claim)
254{
255 DEBUG(1,("pututline_my: not yet implemented\n"));
256 /* BSD implementor: may want to consider (or not) adjusting "lastlog" */
257}
258#endif /* HAVE_PUTUTLINE */
259
260#ifndef HAVE_UPDWTMP
261
262/****************************************************************************
263 Update wtmp file directly. No subroutine interface: probably a BSD system.
264 Credit: Michail Vidiassov <master@iaas.msu.ru>
265****************************************************************************/
266
267static void updwtmp_my(pstring wname, struct utmp *u, BOOL claim)
268{
269 int fd;
270 struct stat buf;
271
272 if (! claim) {
273 /*
274 * BSD-like systems:
275 * may use empty ut_name to distinguish a logout record.
276 *
277 * May need "if defined(SUNOS4)" etc. around some of these,
278 * but try to avoid if possible.
279 *
280 * SunOS 4:
281 * man page indicates ut_name and ut_host both NULL
282 * FreeBSD 4.0:
283 * man page appears not to specify (hints non-NULL)
284 * A correspondent suggest at least ut_name should be NULL
285 */
286#if defined(HAVE_UT_UT_NAME)
287 memset((char *)&u->ut_name, '\0', sizeof(u->ut_name));
288#endif
289#if defined(HAVE_UT_UT_HOST)
290 memset((char *)&u->ut_host, '\0', sizeof(u->ut_host));
291#endif
292 }
293 /* Stolen from logwtmp function in libutil.
294 * May be more locking/blocking is needed?
295 */
296 if ((fd = open(wname, O_WRONLY|O_APPEND, 0)) < 0)
297 return;
298 if (fstat(fd, &buf) == 0) {
299 if (write(fd, (char *)u, sizeof(struct utmp)) != sizeof(struct utmp))
300 (void) ftruncate(fd, buf.st_size);
301 }
302 (void) close(fd);
303}
304#endif /* HAVE_UPDWTMP */
305
306/****************************************************************************
307 Update via utmp/wtmp (not utmpx/wtmpx).
308****************************************************************************/
309
310static void utmp_nox_update(struct utmp *u, BOOL claim)
311{
312 pstring uname, wname;
313#if defined(PUTUTLINE_RETURNS_UTMP)
314 struct utmp *urc;
315#endif /* PUTUTLINE_RETURNS_UTMP */
316
317 uw_pathname(uname, "utmp", ut_pathname);
318 DEBUG(2,("utmp_nox_update: uname:%s\n", uname));
319
320#ifdef HAVE_PUTUTLINE
321 if (strlen(uname) != 0) {
322 utmpname(uname);
323 }
324
325# if defined(PUTUTLINE_RETURNS_UTMP)
326 setutent();
327 urc = pututline(u);
328 endutent();
329 if (urc == NULL) {
330 DEBUG(2,("utmp_nox_update: pututline() failed\n"));
331 return;
332 }
333# else /* PUTUTLINE_RETURNS_UTMP */
334 setutent();
335 pututline(u);
336 endutent();
337# endif /* PUTUTLINE_RETURNS_UTMP */
338
339#else /* HAVE_PUTUTLINE */
340 if (strlen(uname) != 0) {
341 pututline_my(uname, u, claim);
342 }
343#endif /* HAVE_PUTUTLINE */
344
345 uw_pathname(wname, "wtmp", wt_pathname);
346 DEBUG(2,("utmp_nox_update: wname:%s\n", wname));
347 if (strlen(wname) != 0) {
348#ifdef HAVE_UPDWTMP
349 updwtmp(wname, u);
350 /*
351 * updwtmp() and the newer updwtmpx() may be unsymmetrical.
352 * At least one OS, Solaris 2.x declares the former in the
353 * "utmpx" (latter) file and context.
354 * In the Solaris case this is irrelevant: it has both and
355 * we always prefer the "x" case, so doesn't come here.
356 * But are there other systems, with no "x", which lack
357 * updwtmp() perhaps?
358 */
359#else
360 updwtmp_my(wname, u, claim);
361#endif /* HAVE_UPDWTMP */
362 }
363}
364
365/****************************************************************************
366 Copy a string in the utmp structure.
367****************************************************************************/
368
369static void utmp_strcpy(char *dest, const char *src, size_t n)
370{
371 size_t len = 0;
372
373 memset(dest, '\0', n);
374 if (src)
375 len = strlen(src);
376 if (len >= n) {
377 memcpy(dest, src, n);
378 } else {
379 if (len)
380 memcpy(dest, src, len);
381 }
382}
383
384/****************************************************************************
385 Update via utmpx/wtmpx (preferred) or via utmp/wtmp.
386****************************************************************************/
387
388static void sys_utmp_update(struct utmp *u, const char *hostname, BOOL claim)
389{
390#if !defined(HAVE_UTMPX_H)
391 /* No utmpx stuff. Drop to non-x stuff */
392 utmp_nox_update(u, claim);
393#elif !defined(HAVE_PUTUTXLINE)
394 /* Odd. Have utmpx.h but no "pututxline()". Drop to non-x stuff */
395 DEBUG(1,("utmp_update: have utmpx.h but no pututxline() function\n"));
396 utmp_nox_update(u, claim);
397#elif !defined(HAVE_GETUTMPX)
398 /* Odd. Have utmpx.h but no "getutmpx()". Drop to non-x stuff */
399 DEBUG(1,("utmp_update: have utmpx.h but no getutmpx() function\n"));
400 utmp_nox_update(u, claim);
401#else
402 pstring uname, wname;
403 struct utmpx ux, *uxrc;
404
405 getutmpx(u, &ux);
406
407#if defined(HAVE_UX_UT_SYSLEN)
408 if (hostname)
409 ux.ut_syslen = strlen(hostname) + 1; /* include end NULL */
410 else
411 ux.ut_syslen = 0;
412#endif
413#if defined(HAVE_UT_UT_HOST)
414 utmp_strcpy(ux.ut_host, hostname, sizeof(ux.ut_host));
415#endif
416
417 uw_pathname(uname, "utmpx", ux_pathname);
418 uw_pathname(wname, "wtmpx", wx_pathname);
419 DEBUG(2,("utmp_update: uname:%s wname:%s\n", uname, wname));
420 /*
421 * Check for either uname or wname being empty.
422 * Some systems, such as Redhat 6, have a "utmpx.h" which doesn't
423 * define default filenames.
424 * Also, our local installation has not provided an override.
425 * Drop to non-x method. (E.g. RH6 has good defaults in "utmp.h".)
426 */
427 if ((strlen(uname) == 0) || (strlen(wname) == 0)) {
428 utmp_nox_update(u, claim);
429 } else {
430 utmpxname(uname);
431 setutxent();
432 uxrc = pututxline(&ux);
433 endutxent();
434 if (uxrc == NULL) {
435 DEBUG(2,("utmp_update: pututxline() failed\n"));
436 return;
437 }
438 updwtmpx(wname, &ux);
439 }
440#endif /* HAVE_UTMPX_H */
441}
442
443#if defined(HAVE_UT_UT_ID)
444/****************************************************************************
445 Encode the unique connection number into "ut_id".
446****************************************************************************/
447
448static int ut_id_encode(int i, char *fourbyte)
449{
450 int nbase;
451 const char *ut_id_encstr = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
452
453 fourbyte[0] = 'S';
454 fourbyte[1] = 'M';
455
456/*
457 * Encode remaining 2 bytes from 'i'.
458 * 'ut_id_encstr' is the character set on which modulo arithmetic is done.
459 * Example: digits would produce the base-10 numbers from '001'.
460 */
461 nbase = strlen(ut_id_encstr);
462
463 fourbyte[3] = ut_id_encstr[i % nbase];
464 i /= nbase;
465 fourbyte[2] = ut_id_encstr[i % nbase];
466 i /= nbase;
467
468 return(i); /* 0: good; else overflow */
469}
470#endif /* defined(HAVE_UT_UT_ID) */
471
472
473/*
474 fill a system utmp structure given all the info we can gather
475*/
476static BOOL sys_utmp_fill(struct utmp *u,
477 const char *username, const char *hostname,
478 struct in_addr *ipaddr,
479 const char *id_str, int id_num)
480{
481 struct timeval timeval;
482
483 /*
484 * ut_name, ut_user:
485 * Several (all?) systems seems to define one as the other.
486 * It is easier and clearer simply to let the following take its course,
487 * rather than to try to detect and optimise.
488 */
489#if defined(HAVE_UT_UT_USER)
490 utmp_strcpy(u->ut_user, username, sizeof(u->ut_user));
491#elif defined(HAVE_UT_UT_NAME)
492 utmp_strcpy(u->ut_name, username, sizeof(u->ut_name));
493#endif
494
495 /*
496 * ut_line:
497 * If size limit proves troublesome, then perhaps use "ut_id_encode()".
498 */
499 if (strlen(id_str) > sizeof(u->ut_line)) {
500 DEBUG(1,("id_str [%s] is too long for %lu char utmp field\n",
501 id_str, (unsigned long)sizeof(u->ut_line)));
502 return False;
503 }
504 utmp_strcpy(u->ut_line, id_str, sizeof(u->ut_line));
505
506#if defined(HAVE_UT_UT_PID)
507 u->ut_pid = sys_getpid();
508#endif
509
510/*
511 * ut_time, ut_tv:
512 * Some have one, some the other. Many have both, but defined (aliased).
513 * It is easier and clearer simply to let the following take its course.
514 * But note that we do the more precise ut_tv as the final assignment.
515 */
516#if defined(HAVE_UT_UT_TIME)
517 GetTimeOfDay(&timeval);
518 u->ut_time = timeval.tv_sec;
519#elif defined(HAVE_UT_UT_TV)
520 GetTimeOfDay(&timeval);
521 u->ut_tv = timeval;
522#else
523#error "with-utmp must have UT_TIME or UT_TV"
524#endif
525
526#if defined(HAVE_UT_UT_HOST)
527 utmp_strcpy(u->ut_host, hostname, sizeof(u->ut_host));
528#endif
529#if defined(HAVE_UT_UT_ADDR)
530 if (ipaddr)
531 u->ut_addr = ipaddr->s_addr;
532 /*
533 * "(unsigned long) ut_addr" apparently exists on at least HP-UX 10.20.
534 * Volunteer to implement, please ...
535 */
536#endif
537
538#if defined(HAVE_UT_UT_ID)
539 if (ut_id_encode(id_num, u->ut_id) != 0) {
540 DEBUG(1,("utmp_fill: cannot encode id %d\n", id_num));
541 return False;
542 }
543#endif
544
545 return True;
546}
547
548/****************************************************************************
549 Close a connection.
550****************************************************************************/
551
552void sys_utmp_yield(const char *username, const char *hostname,
553 struct in_addr *ipaddr,
554 const char *id_str, int id_num)
555{
556 struct utmp u;
557
558 ZERO_STRUCT(u);
559
560#if defined(HAVE_UT_UT_EXIT)
561 u.ut_exit.e_termination = 0;
562 u.ut_exit.e_exit = 0;
563#endif
564
565#if defined(HAVE_UT_UT_TYPE)
566 u.ut_type = DEAD_PROCESS;
567#endif
568
569 if (!sys_utmp_fill(&u, username, hostname, ipaddr, id_str, id_num)) return;
570
571 sys_utmp_update(&u, NULL, False);
572}
573
574/****************************************************************************
575 Claim a entry in whatever utmp system the OS uses.
576****************************************************************************/
577
578void sys_utmp_claim(const char *username, const char *hostname,
579 struct in_addr *ipaddr,
580 const char *id_str, int id_num)
581{
582 struct utmp u;
583
584 ZERO_STRUCT(u);
585
586#if defined(HAVE_UT_UT_TYPE)
587 u.ut_type = USER_PROCESS;
588#endif
589
590 if (!sys_utmp_fill(&u, username, hostname, ipaddr, id_str, id_num)) return;
591
592 sys_utmp_update(&u, hostname, True);
593}
594
595#endif /* WITH_UTMP */
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