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 3 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, see <http://www.gnu.org/licenses/>. 19*/ 20 21#include "includes.h" 22 23/**************************************************************************** 24Reflect connection status in utmp/wtmp files. 25 T.D.Lee@durham.ac.uk September 1999 26 27 With grateful thanks since then to many who have helped port it to 28 different operating systems. The variety of OS quirks thereby 29 uncovered is amazing... 30 31Hints for porting: 32 o Always attempt to use programmatic interface (pututline() etc.) 33 Indeed, at present only programmatic use is supported. 34 o The only currently supported programmatic interface to "wtmp{,x}" 35 is through "updwtmp*()" routines. 36 o The "x" (utmpx/wtmpx; HAVE_UTMPX_H) seems preferable. 37 o The HAVE_* items should identify supported features. 38 o If at all possible, avoid "if defined(MY-OS)" constructions. 39 40OS observations and status: 41 Almost every OS seems to have its own quirks. 42 43 Solaris 2.x: 44 Tested on 2.6 and 2.7; should be OK on other flavours. 45 AIX: 46 Apparently has utmpx.h but doesn't implement. 47 OSF: 48 Has utmpx.h, but (e.g.) no "getutmpx()". (Is this like AIX ?) 49 Redhat 6: 50 utmpx.h seems not to set default filenames. non-x better. 51 IRIX 6.5: 52 Not tested. Appears to have "x". 53 HP-UX 9.x: 54 Not tested. Appears to lack "x". 55 HP-UX 10.x: 56 Not tested. 57 "updwtmp*()" routines seem absent, so no current wtmp* support. 58 Has "ut_addr": probably trivial to implement (although remember 59 that IPv6 is coming...). 60 61 FreeBSD: 62 No "putut*()" type of interface. 63 No "ut_type" and associated defines. 64 Write files directly. Alternatively use its login(3)/logout(3). 65 SunOS 4: 66 Not tested. Resembles FreeBSD, but no login()/logout(). 67 68lastlog: 69 Should "lastlog" files, if any, be updated? 70 BSD systems (SunOS 4, FreeBSD): 71 o Prominent mention on man pages. 72 System-V (e.g. Solaris 2): 73 o No mention on man pages, even under "man -k". 74 o Has a "/var/adm/lastlog" file, but pututxline() etc. seem 75 not to touch it. 76 o Despite downplaying (above), nevertheless has <lastlog.h>. 77 So perhaps UN*X "lastlog" facility is intended for tty/terminal only? 78 79Notes: 80 Each connection requires a small number (starting at 0, working up) 81 to represent the line. This must be unique within and across all 82 smbd processes. It is the 'id_num' from Samba's session.c code. 83 84 The 4 byte 'ut_id' component is vital to distinguish connections, 85 of which there could be several hundred or even thousand. 86 Entries seem to be printable characters, with optional NULL pads. 87 88 We need to be distinct from other entries in utmp/wtmp. 89 90 Observed things: therefore avoid them. Add to this list please. 91 From Solaris 2.x (because that's what I have): 92 'sN' : run-levels; N: [0-9] 93 'co' : console 94 'CC' : arbitrary things; C: [a-z] 95 'rXNN' : rlogin; N: [0-9]; X: [0-9a-z] 96 'tXNN' : rlogin; N: [0-9]; X: [0-9a-z] 97 '/NNN' : Solaris CDE 98 'ftpZ' : ftp (Z is the number 255, aka 0377, aka 0xff) 99 Mostly a record uses the same 'ut_id' in both "utmp" and "wtmp", 100 but differences have been seen. 101 102 Arbitrarily I have chosen to use a distinctive 'SM' for the 103 first two bytes. 104 105 The remaining two bytes encode the session 'id_num' (see above). 106 Our caller (session.c) should note our 16-bit limitation. 107 108****************************************************************************/ 109 110#ifndef WITH_UTMP 111/* 112 * Not WITH_UTMP? Simply supply dummy routines. 113 */ 114 115void sys_utmp_claim(const char *username, const char *hostname, 116 const char *ip_addr_str, 117 const char *id_str, int id_num) 118{} 119 120void sys_utmp_yield(const char *username, const char *hostname, 121 const char *ip_addr_str, 122 const char *id_str, int id_num) 123{} 124 125#else /* WITH_UTMP */ 126 127#include <utmp.h> 128 129#ifdef HAVE_UTMPX_H 130#include <utmpx.h> 131#endif 132 133/* BSD systems: some may need lastlog.h (SunOS 4), some may not (FreeBSD) */ 134/* Some System-V systems (e.g. Solaris 2) declare this too. */ 135#ifdef HAVE_LASTLOG_H 136#include <lastlog.h> 137#endif 138 139/**************************************************************************** 140 Default paths to various {u,w}tmp{,x} files. 141****************************************************************************/ 142 143#ifdef HAVE_UTMPX_H 144 145static const char * const ux_pathname = 146# if defined (UTMPX_FILE) 147 UTMPX_FILE ; 148# elif defined (_UTMPX_FILE) 149 _UTMPX_FILE ; 150# elif defined (_PATH_UTMPX) 151 _PATH_UTMPX ; 152# else 153 "" ; 154# endif 155 156static const char * const wx_pathname = 157# if defined (WTMPX_FILE) 158 WTMPX_FILE ; 159# elif defined (_WTMPX_FILE) 160 _WTMPX_FILE ; 161# elif defined (_PATH_WTMPX) 162 _PATH_WTMPX ; 163# else 164 "" ; 165# endif 166 167#endif /* HAVE_UTMPX_H */ 168 169static const char * const ut_pathname = 170# if defined (UTMP_FILE) 171 UTMP_FILE ; 172# elif defined (_UTMP_FILE) 173 _UTMP_FILE ; 174# elif defined (_PATH_UTMP) 175 _PATH_UTMP ; 176# else 177 "" ; 178# endif 179 180static const char * const wt_pathname = 181# if defined (WTMP_FILE) 182 WTMP_FILE ; 183# elif defined (_WTMP_FILE) 184 _WTMP_FILE ; 185# elif defined (_PATH_WTMP) 186 _PATH_WTMP ; 187# else 188 "" ; 189# endif 190 191/* BSD-like systems might want "lastlog" support. */ 192#if 0 /* *** Not yet implemented */ 193#ifndef HAVE_PUTUTLINE /* see "pututline_my()" */ 194static const char *ll_pathname = 195# if defined (_PATH_LASTLOG) /* what other names (if any?) */ 196 _PATH_LASTLOG ; 197# else 198 "" ; 199# endif /* _PATH_LASTLOG */ 200#endif /* HAVE_PUTUTLINE */ 201#endif 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 char *uw_pathname(TALLOC_CTX *ctx, 212 const char *uw_name, 213 const char *uw_default) 214{ 215 char *dirname = NULL; 216 217 /* For w-files, first look for explicit "wtmp dir" */ 218 if (uw_name[0] == 'w') { 219 dirname = talloc_strdup(ctx, lp_wtmpdir()); 220 if (!dirname) { 221 return NULL; 222 } 223 trim_char(dirname,'\0','/'); 224 } 225 226 /* For u-files and non-explicit w-dir, look for "utmp dir" */ 227 if ((dirname == NULL) || (strlen(dirname) == 0)) { 228 dirname = talloc_strdup(ctx, lp_utmpdir()); 229 if (!dirname) { 230 return NULL; 231 } 232 trim_char(dirname,'\0','/'); 233 } 234 235 /* If explicit directory above, use it */ 236 if (dirname && strlen(dirname) != 0) { 237 return talloc_asprintf(ctx, 238 "%s/%s", 239 dirname, 240 uw_name); 241 } 242 243 /* No explicit directory: attempt to use default paths */ 244 if (strlen(uw_default) == 0) { 245 /* No explicit setting, no known default. 246 * Has it yet been ported to this OS? 247 */ 248 DEBUG(2,("uw_pathname: unable to determine pathname\n")); 249 } 250 return talloc_strdup(ctx, uw_default); 251} 252 253#ifndef HAVE_PUTUTLINE 254/**************************************************************************** 255 Update utmp file directly. No subroutine interface: probably a BSD system. 256****************************************************************************/ 257 258static void pututline_my(const char *uname, struct utmp *u, bool claim) 259{ 260 DEBUG(1,("pututline_my: not yet implemented\n")); 261 /* BSD implementor: may want to consider (or not) adjusting "lastlog" */ 262} 263#endif /* HAVE_PUTUTLINE */ 264 265#ifndef HAVE_UPDWTMP 266 267/**************************************************************************** 268 Update wtmp file directly. No subroutine interface: probably a BSD system. 269 Credit: Michail Vidiassov <master@iaas.msu.ru> 270****************************************************************************/ 271 272static void updwtmp_my(const char *wname, struct utmp *u, bool claim) 273{ 274 int fd; 275 struct stat buf; 276 277 if (! claim) { 278 /* 279 * BSD-like systems: 280 * may use empty ut_name to distinguish a logout record. 281 * 282 * May need "if defined(SUNOS4)" etc. around some of these, 283 * but try to avoid if possible. 284 * 285 * SunOS 4: 286 * man page indicates ut_name and ut_host both NULL 287 * FreeBSD 4.0: 288 * man page appears not to specify (hints non-NULL) 289 * A correspondent suggest at least ut_name should be NULL 290 */ 291#if defined(HAVE_UT_UT_NAME) 292 memset((char *)&u->ut_name, '\0', sizeof(u->ut_name)); 293#endif 294#if defined(HAVE_UT_UT_HOST) 295 memset((char *)&u->ut_host, '\0', sizeof(u->ut_host)); 296#endif 297 } 298 /* Stolen from logwtmp function in libutil. 299 * May be more locking/blocking is needed? 300 */ 301 if ((fd = open(wname, O_WRONLY|O_APPEND, 0)) < 0) 302 return; 303 if (fstat(fd, &buf) == 0) { 304 if (write(fd, (char *)u, sizeof(struct utmp)) != sizeof(struct utmp)) 305 (void) ftruncate(fd, buf.st_size); 306 } 307 (void) close(fd); 308} 309#endif /* HAVE_UPDWTMP */ 310 311/**************************************************************************** 312 Update via utmp/wtmp (not utmpx/wtmpx). 313****************************************************************************/ 314 315static void utmp_nox_update(struct utmp *u, bool claim) 316{ 317 char *uname = NULL; 318 char *wname = NULL; 319#if defined(PUTUTLINE_RETURNS_UTMP) 320 struct utmp *urc; 321#endif /* PUTUTLINE_RETURNS_UTMP */ 322 323 uname = uw_pathname(talloc_tos(), "utmp", ut_pathname); 324 if (!uname) { 325 return; 326 } 327 DEBUG(2,("utmp_nox_update: uname:%s\n", uname)); 328 329#ifdef HAVE_PUTUTLINE 330 if (strlen(uname) != 0) { 331 utmpname(uname); 332 } 333 334# if defined(PUTUTLINE_RETURNS_UTMP) 335 setutent(); 336 urc = pututline(u); 337 endutent(); 338 if (urc == NULL) { 339 DEBUG(2,("utmp_nox_update: pututline() failed\n")); 340 return; 341 } 342# else /* PUTUTLINE_RETURNS_UTMP */ 343 setutent(); 344 pututline(u); 345 endutent(); 346# endif /* PUTUTLINE_RETURNS_UTMP */ 347 348#else /* HAVE_PUTUTLINE */ 349 if (strlen(uname) != 0) { 350 pututline_my(uname, u, claim); 351 } 352#endif /* HAVE_PUTUTLINE */ 353 354 wname = uw_pathname(talloc_tos(), "wtmp", wt_pathname); 355 if (!wname) { 356 return; 357 } 358 DEBUG(2,("utmp_nox_update: wname:%s\n", wname)); 359 if (strlen(wname) != 0) { 360#ifdef HAVE_UPDWTMP 361 updwtmp(wname, u); 362 /* 363 * updwtmp() and the newer updwtmpx() may be unsymmetrical. 364 * At least one OS, Solaris 2.x declares the former in the 365 * "utmpx" (latter) file and context. 366 * In the Solaris case this is irrelevant: it has both and 367 * we always prefer the "x" case, so doesn't come here. 368 * But are there other systems, with no "x", which lack 369 * updwtmp() perhaps? 370 */ 371#else 372 updwtmp_my(wname, u, claim); 373#endif /* HAVE_UPDWTMP */ 374 } 375} 376 377/**************************************************************************** 378 Copy a string in the utmp structure. 379****************************************************************************/ 380 381static void utmp_strcpy(char *dest, const char *src, size_t n) 382{ 383 size_t len = 0; 384 385 memset(dest, '\0', n); 386 if (src) 387 len = strlen(src); 388 if (len >= n) { 389 memcpy(dest, src, n); 390 } else { 391 if (len) 392 memcpy(dest, src, len); 393 } 394} 395 396/**************************************************************************** 397 Update via utmpx/wtmpx (preferred) or via utmp/wtmp. 398****************************************************************************/ 399 400static void sys_utmp_update(struct utmp *u, const char *hostname, bool claim) 401{ 402#if !defined(HAVE_UTMPX_H) 403 /* No utmpx stuff. Drop to non-x stuff */ 404 utmp_nox_update(u, claim); 405#elif !defined(HAVE_PUTUTXLINE) 406 /* Odd. Have utmpx.h but no "pututxline()". Drop to non-x stuff */ 407 DEBUG(1,("utmp_update: have utmpx.h but no pututxline() function\n")); 408 utmp_nox_update(u, claim); 409#elif !defined(HAVE_GETUTMPX) 410 /* Odd. Have utmpx.h but no "getutmpx()". Drop to non-x stuff */ 411 DEBUG(1,("utmp_update: have utmpx.h but no getutmpx() function\n")); 412 utmp_nox_update(u, claim); 413#elif !defined(HAVE_UPDWTMPX) 414 /* Have utmpx.h but no "updwtmpx()". Drop to non-x stuff */ 415 DEBUG(1,("utmp_update: have utmpx.h but no updwtmpx() function\n")); 416 utmp_nox_update(u, claim); 417#else 418 char *uname = NULL; 419 char *wname = NULL; 420 struct utmpx ux, *uxrc; 421 422 getutmpx(u, &ux); 423 424#if defined(HAVE_UX_UT_SYSLEN) 425 if (hostname) 426 ux.ut_syslen = strlen(hostname) + 1; /* include end NULL */ 427 else 428 ux.ut_syslen = 0; 429#endif 430#if defined(HAVE_UT_UT_HOST) 431 utmp_strcpy(ux.ut_host, hostname, sizeof(ux.ut_host)); 432#endif 433 434 uname = uw_pathname(talloc_tos(), "utmpx", ux_pathname); 435 wname = uw_pathname(talloc_tos(), "wtmpx", wx_pathname); 436 if (uname && wname) { 437 DEBUG(2,("utmp_update: uname:%s wname:%s\n", uname, wname)); 438 } 439 440 /* 441 * Check for either uname or wname being empty. 442 * Some systems, such as Redhat 6, have a "utmpx.h" which doesn't 443 * define default filenames. 444 * Also, our local installation has not provided an override. 445 * Drop to non-x method. (E.g. RH6 has good defaults in "utmp.h".) 446 */ 447 if (!uname || !wname || (strlen(uname) == 0) || (strlen(wname) == 0)) { 448 utmp_nox_update(u, claim); 449 } else { 450 utmpxname(uname); 451 setutxent(); 452 uxrc = pututxline(&ux); 453 endutxent(); 454 if (uxrc == NULL) { 455 DEBUG(2,("utmp_update: pututxline() failed\n")); 456 return; 457 } 458 updwtmpx(wname, &ux); 459 } 460#endif /* HAVE_UTMPX_H */ 461} 462 463#if defined(HAVE_UT_UT_ID) 464/**************************************************************************** 465 Encode the unique connection number into "ut_id". 466****************************************************************************/ 467 468static int ut_id_encode(int i, char *fourbyte) 469{ 470 int nbase; 471 const char *ut_id_encstr = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"; 472 473 fourbyte[0] = 'S'; 474 fourbyte[1] = 'M'; 475 476/* 477 * Encode remaining 2 bytes from 'i'. 478 * 'ut_id_encstr' is the character set on which modulo arithmetic is done. 479 * Example: digits would produce the base-10 numbers from '001'. 480 */ 481 nbase = strlen(ut_id_encstr); 482 483 fourbyte[3] = ut_id_encstr[i % nbase]; 484 i /= nbase; 485 fourbyte[2] = ut_id_encstr[i % nbase]; 486 i /= nbase; 487 488 return(i); /* 0: good; else overflow */ 489} 490#endif /* defined(HAVE_UT_UT_ID) */ 491 492 493/* 494 fill a system utmp structure given all the info we can gather 495*/ 496static bool sys_utmp_fill(struct utmp *u, 497 const char *username, const char *hostname, 498 const char *ip_addr_str, 499 const char *id_str, int id_num) 500{ 501 struct timeval timeval; 502 503 /* 504 * ut_name, ut_user: 505 * Several (all?) systems seems to define one as the other. 506 * It is easier and clearer simply to let the following take its course, 507 * rather than to try to detect and optimise. 508 */ 509#if defined(HAVE_UT_UT_USER) 510 utmp_strcpy(u->ut_user, username, sizeof(u->ut_user)); 511#elif defined(HAVE_UT_UT_NAME) 512 utmp_strcpy(u->ut_name, username, sizeof(u->ut_name)); 513#endif 514 515 /* 516 * ut_line: 517 * If size limit proves troublesome, then perhaps use "ut_id_encode()". 518 */ 519 if (strlen(id_str) > sizeof(u->ut_line)) { 520 DEBUG(1,("id_str [%s] is too long for %lu char utmp field\n", 521 id_str, (unsigned long)sizeof(u->ut_line))); 522 return False; 523 } 524 utmp_strcpy(u->ut_line, id_str, sizeof(u->ut_line)); 525 526#if defined(HAVE_UT_UT_PID) 527 u->ut_pid = sys_getpid(); 528#endif 529 530/* 531 * ut_time, ut_tv: 532 * Some have one, some the other. Many have both, but defined (aliased). 533 * It is easier and clearer simply to let the following take its course. 534 * But note that we do the more precise ut_tv as the final assignment. 535 */ 536#if defined(HAVE_UT_UT_TIME) 537 GetTimeOfDay(&timeval); 538 u->ut_time = timeval.tv_sec; 539#elif defined(HAVE_UT_UT_TV) 540 GetTimeOfDay(&timeval); 541 u->ut_tv = timeval; 542#else 543#error "with-utmp must have UT_TIME or UT_TV" 544#endif 545 546#if defined(HAVE_UT_UT_HOST) 547 utmp_strcpy(u->ut_host, hostname, sizeof(u->ut_host)); 548#endif 549#if defined(HAVE_IPV6) && defined(HAVE_UT_UT_ADDR_V6) 550 memset(&u->ut_addr_v6, '\0', sizeof(u->ut_addr_v6)); 551 if (ip_addr_str) { 552 struct in6_addr addr; 553 if (inet_pton(AF_INET6, ip_addr_str, &addr) > 0) { 554 memcpy(&u->ut_addr_v6, &addr, sizeof(addr)); 555 } 556 } 557#elif defined(HAVE_UT_UT_ADDR) 558 memset(&u->ut_addr, '\0', sizeof(u->ut_addr)); 559 if (ip_addr_str) { 560 struct in_addr addr; 561 if (inet_pton(AF_INET, ip_addr_str, &addr) > 0) { 562 memcpy(&u->ut_addr, &addr, sizeof(addr)); 563 } 564 } 565 /* 566 * "(unsigned long) ut_addr" apparently exists on at least HP-UX 10.20. 567 * Volunteer to implement, please ... 568 */ 569#endif 570 571#if defined(HAVE_UT_UT_ID) 572 if (ut_id_encode(id_num, u->ut_id) != 0) { 573 DEBUG(1,("utmp_fill: cannot encode id %d\n", id_num)); 574 return False; 575 } 576#endif 577 578 return True; 579} 580 581/**************************************************************************** 582 Close a connection. 583****************************************************************************/ 584 585void sys_utmp_yield(const char *username, const char *hostname, 586 const char *ip_addr_str, 587 const char *id_str, int id_num) 588{ 589 struct utmp u; 590 591 ZERO_STRUCT(u); 592 593#if defined(HAVE_UT_UT_EXIT) 594 u.ut_exit.e_termination = 0; 595 u.ut_exit.e_exit = 0; 596#endif 597 598#if defined(HAVE_UT_UT_TYPE) 599 u.ut_type = DEAD_PROCESS; 600#endif 601 602 if (!sys_utmp_fill(&u, username, hostname, ip_addr_str, id_str, id_num)) 603 return; 604 605 sys_utmp_update(&u, NULL, False); 606} 607 608/**************************************************************************** 609 Claim a entry in whatever utmp system the OS uses. 610****************************************************************************/ 611 612void sys_utmp_claim(const char *username, const char *hostname, 613 const char *ip_addr_str, 614 const char *id_str, int id_num) 615{ 616 struct utmp u; 617 618 ZERO_STRUCT(u); 619 620#if defined(HAVE_UT_UT_TYPE) 621 u.ut_type = USER_PROCESS; 622#endif 623 624 if (!sys_utmp_fill(&u, username, hostname, ip_addr_str, id_str, id_num)) 625 return; 626 627 sys_utmp_update(&u, hostname, True); 628} 629 630#endif /* WITH_UTMP */ 631