loginrec.c revision 149753
1/* 2 * Copyright (c) 2000 Andre Lucas. All rights reserved. 3 * Portions copyright (c) 1998 Todd C. Miller 4 * Portions copyright (c) 1996 Jason Downs 5 * Portions copyright (c) 1996 Theo de Raadt 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28/* 29 * The btmp logging code is derived from login.c from util-linux and is under 30 * the the following license: 31 * 32 * Copyright (c) 1980, 1987, 1988 The Regents of the University of California. 33 * All rights reserved. 34 * 35 * Redistribution and use in source and binary forms are permitted 36 * provided that the above copyright notice and this paragraph are 37 * duplicated in all such forms and that any documentation, 38 * advertising materials, and other materials related to such 39 * distribution and use acknowledge that the software was developed 40 * by the University of California, Berkeley. The name of the 41 * University may not be used to endorse or promote products derived 42 * from this software without specific prior written permission. 43 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 44 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 45 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 46 */ 47 48 49/** 50 ** loginrec.c: platform-independent login recording and lastlog retrieval 51 **/ 52 53/* 54 * The new login code explained 55 * ============================ 56 * 57 * This code attempts to provide a common interface to login recording 58 * (utmp and friends) and last login time retrieval. 59 * 60 * Its primary means of achieving this is to use 'struct logininfo', a 61 * union of all the useful fields in the various different types of 62 * system login record structures one finds on UNIX variants. 63 * 64 * We depend on autoconf to define which recording methods are to be 65 * used, and which fields are contained in the relevant data structures 66 * on the local system. Many C preprocessor symbols affect which code 67 * gets compiled here. 68 * 69 * The code is designed to make it easy to modify a particular 70 * recording method, without affecting other methods nor requiring so 71 * many nested conditional compilation blocks as were commonplace in 72 * the old code. 73 * 74 * For login recording, we try to use the local system's libraries as 75 * these are clearly most likely to work correctly. For utmp systems 76 * this usually means login() and logout() or setutent() etc., probably 77 * in libutil, along with logwtmp() etc. On these systems, we fall back 78 * to writing the files directly if we have to, though this method 79 * requires very thorough testing so we do not corrupt local auditing 80 * information. These files and their access methods are very system 81 * specific indeed. 82 * 83 * For utmpx systems, the corresponding library functions are 84 * setutxent() etc. To the author's knowledge, all utmpx systems have 85 * these library functions and so no direct write is attempted. If such 86 * a system exists and needs support, direct analogues of the [uw]tmp 87 * code should suffice. 88 * 89 * Retrieving the time of last login ('lastlog') is in some ways even 90 * more problemmatic than login recording. Some systems provide a 91 * simple table of all users which we seek based on uid and retrieve a 92 * relatively standard structure. Others record the same information in 93 * a directory with a separate file, and others don't record the 94 * information separately at all. For systems in the latter category, 95 * we look backwards in the wtmp or wtmpx file for the last login entry 96 * for our user. Naturally this is slower and on busy systems could 97 * incur a significant performance penalty. 98 * 99 * Calling the new code 100 * -------------------- 101 * 102 * In OpenSSH all login recording and retrieval is performed in 103 * login.c. Here you'll find working examples. Also, in the logintest.c 104 * program there are more examples. 105 * 106 * Internal handler calling method 107 * ------------------------------- 108 * 109 * When a call is made to login_login() or login_logout(), both 110 * routines set a struct logininfo flag defining which action (log in, 111 * or log out) is to be taken. They both then call login_write(), which 112 * calls whichever of the many structure-specific handlers autoconf 113 * selects for the local system. 114 * 115 * The handlers themselves handle system data structure specifics. Both 116 * struct utmp and struct utmpx have utility functions (see 117 * construct_utmp*()) to try to make it simpler to add extra systems 118 * that introduce new features to either structure. 119 * 120 * While it may seem terribly wasteful to replicate so much similar 121 * code for each method, experience has shown that maintaining code to 122 * write both struct utmp and utmpx in one function, whilst maintaining 123 * support for all systems whether they have library support or not, is 124 * a difficult and time-consuming task. 125 * 126 * Lastlog support proceeds similarly. Functions login_get_lastlog() 127 * (and its OpenSSH-tuned friend login_get_lastlog_time()) call 128 * getlast_entry(), which tries one of three methods to find the last 129 * login time. It uses local system lastlog support if it can, 130 * otherwise it tries wtmp or wtmpx before giving up and returning 0, 131 * meaning "tilt". 132 * 133 * Maintenance 134 * ----------- 135 * 136 * In many cases it's possible to tweak autoconf to select the correct 137 * methods for a particular platform, either by improving the detection 138 * code (best), or by presetting DISABLE_<method> or CONF_<method>_FILE 139 * symbols for the platform. 140 * 141 * Use logintest to check which symbols are defined before modifying 142 * configure.ac and loginrec.c. (You have to build logintest yourself 143 * with 'make logintest' as it's not built by default.) 144 * 145 * Otherwise, patches to the specific method(s) are very helpful! 146 */ 147 148#include "includes.h" 149 150#include "ssh.h" 151#include "xmalloc.h" 152#include "loginrec.h" 153#include "log.h" 154#include "atomicio.h" 155#include "packet.h" 156#include "canohost.h" 157#include "auth.h" 158#include "buffer.h" 159 160#ifdef HAVE_UTIL_H 161# include <util.h> 162#endif 163 164#ifdef HAVE_LIBUTIL_H 165# include <libutil.h> 166#endif 167 168RCSID("$Id: loginrec.c,v 1.70 2005/07/17 07:26:44 djm Exp $"); 169RCSID("$FreeBSD: head/crypto/openssh/loginrec.c 149753 2005-09-03 07:04:25Z des $"); 170 171/** 172 ** prototypes for helper functions in this file 173 **/ 174 175#if HAVE_UTMP_H 176void set_utmp_time(struct logininfo *li, struct utmp *ut); 177void construct_utmp(struct logininfo *li, struct utmp *ut); 178#endif 179 180#ifdef HAVE_UTMPX_H 181void set_utmpx_time(struct logininfo *li, struct utmpx *ut); 182void construct_utmpx(struct logininfo *li, struct utmpx *ut); 183#endif 184 185int utmp_write_entry(struct logininfo *li); 186int utmpx_write_entry(struct logininfo *li); 187int wtmp_write_entry(struct logininfo *li); 188int wtmpx_write_entry(struct logininfo *li); 189int lastlog_write_entry(struct logininfo *li); 190int syslogin_write_entry(struct logininfo *li); 191 192int getlast_entry(struct logininfo *li); 193int lastlog_get_entry(struct logininfo *li); 194int wtmp_get_entry(struct logininfo *li); 195int wtmpx_get_entry(struct logininfo *li); 196 197extern Buffer loginmsg; 198 199/* pick the shortest string */ 200#define MIN_SIZEOF(s1,s2) (sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2)) 201 202/** 203 ** platform-independent login functions 204 **/ 205 206/* 207 * login_login(struct logininfo *) - Record a login 208 * 209 * Call with a pointer to a struct logininfo initialised with 210 * login_init_entry() or login_alloc_entry() 211 * 212 * Returns: 213 * >0 if successful 214 * 0 on failure (will use OpenSSH's logging facilities for diagnostics) 215 */ 216int 217login_login(struct logininfo *li) 218{ 219 li->type = LTYPE_LOGIN; 220 return (login_write(li)); 221} 222 223 224/* 225 * login_logout(struct logininfo *) - Record a logout 226 * 227 * Call as with login_login() 228 * 229 * Returns: 230 * >0 if successful 231 * 0 on failure (will use OpenSSH's logging facilities for diagnostics) 232 */ 233int 234login_logout(struct logininfo *li) 235{ 236 li->type = LTYPE_LOGOUT; 237 return (login_write(li)); 238} 239 240/* 241 * login_get_lastlog_time(int) - Retrieve the last login time 242 * 243 * Retrieve the last login time for the given uid. Will try to use the 244 * system lastlog facilities if they are available, but will fall back 245 * to looking in wtmp/wtmpx if necessary 246 * 247 * Returns: 248 * 0 on failure, or if user has never logged in 249 * Time in seconds from the epoch if successful 250 * 251 * Useful preprocessor symbols: 252 * DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog 253 * info 254 * USE_LASTLOG: If set, indicates the presence of system lastlog 255 * facilities. If this and DISABLE_LASTLOG are not set, 256 * try to retrieve lastlog information from wtmp/wtmpx. 257 */ 258unsigned int 259login_get_lastlog_time(const int uid) 260{ 261 struct logininfo li; 262 263 if (login_get_lastlog(&li, uid)) 264 return (li.tv_sec); 265 else 266 return (0); 267} 268 269/* 270 * login_get_lastlog(struct logininfo *, int) - Retrieve a lastlog entry 271 * 272 * Retrieve a logininfo structure populated (only partially) with 273 * information from the system lastlog data, or from wtmp/wtmpx if no 274 * system lastlog information exists. 275 * 276 * Note this routine must be given a pre-allocated logininfo. 277 * 278 * Returns: 279 * >0: A pointer to your struct logininfo if successful 280 * 0 on failure (will use OpenSSH's logging facilities for diagnostics) 281 */ 282struct logininfo * 283login_get_lastlog(struct logininfo *li, const int uid) 284{ 285 struct passwd *pw; 286 287 memset(li, '\0', sizeof(*li)); 288 li->uid = uid; 289 290 /* 291 * If we don't have a 'real' lastlog, we need the username to 292 * reliably search wtmp(x) for the last login (see 293 * wtmp_get_entry().) 294 */ 295 pw = getpwuid(uid); 296 if (pw == NULL) 297 fatal("%s: Cannot find account for uid %i", __func__, uid); 298 299 /* No MIN_SIZEOF here - we absolutely *must not* truncate the 300 * username (XXX - so check for trunc!) */ 301 strlcpy(li->username, pw->pw_name, sizeof(li->username)); 302 303 if (getlast_entry(li)) 304 return (li); 305 else 306 return (NULL); 307} 308 309 310/* 311 * login_alloc_entry(int, char*, char*, char*) - Allocate and initialise 312 * a logininfo structure 313 * 314 * This function creates a new struct logininfo, a data structure 315 * meant to carry the information required to portably record login info. 316 * 317 * Returns a pointer to a newly created struct logininfo. If memory 318 * allocation fails, the program halts. 319 */ 320struct 321logininfo *login_alloc_entry(int pid, const char *username, 322 const char *hostname, const char *line) 323{ 324 struct logininfo *newli; 325 326 newli = xmalloc(sizeof(*newli)); 327 login_init_entry(newli, pid, username, hostname, line); 328 return (newli); 329} 330 331 332/* login_free_entry(struct logininfo *) - free struct memory */ 333void 334login_free_entry(struct logininfo *li) 335{ 336 xfree(li); 337} 338 339 340/* login_init_entry(struct logininfo *, int, char*, char*, char*) 341 * - initialise a struct logininfo 342 * 343 * Populates a new struct logininfo, a data structure meant to carry 344 * the information required to portably record login info. 345 * 346 * Returns: 1 347 */ 348int 349login_init_entry(struct logininfo *li, int pid, const char *username, 350 const char *hostname, const char *line) 351{ 352 struct passwd *pw; 353 354 memset(li, 0, sizeof(*li)); 355 356 li->pid = pid; 357 358 /* set the line information */ 359 if (line) 360 line_fullname(li->line, line, sizeof(li->line)); 361 362 if (username) { 363 strlcpy(li->username, username, sizeof(li->username)); 364 pw = getpwnam(li->username); 365 if (pw == NULL) { 366 fatal("%s: Cannot find user \"%s\"", __func__, 367 li->username); 368 } 369 li->uid = pw->pw_uid; 370 } 371 372 if (hostname) 373 strlcpy(li->hostname, hostname, sizeof(li->hostname)); 374 375 return (1); 376} 377 378/* 379 * login_set_current_time(struct logininfo *) - set the current time 380 * 381 * Set the current time in a logininfo structure. This function is 382 * meant to eliminate the need to deal with system dependencies for 383 * time handling. 384 */ 385void 386login_set_current_time(struct logininfo *li) 387{ 388 struct timeval tv; 389 390 gettimeofday(&tv, NULL); 391 392 li->tv_sec = tv.tv_sec; 393 li->tv_usec = tv.tv_usec; 394} 395 396/* copy a sockaddr_* into our logininfo */ 397void 398login_set_addr(struct logininfo *li, const struct sockaddr *sa, 399 const unsigned int sa_size) 400{ 401 unsigned int bufsize = sa_size; 402 403 /* make sure we don't overrun our union */ 404 if (sizeof(li->hostaddr) < sa_size) 405 bufsize = sizeof(li->hostaddr); 406 407 memcpy(&li->hostaddr.sa, sa, bufsize); 408} 409 410 411/** 412 ** login_write: Call low-level recording functions based on autoconf 413 ** results 414 **/ 415int 416login_write(struct logininfo *li) 417{ 418#ifndef HAVE_CYGWIN 419 if (geteuid() != 0) { 420 logit("Attempt to write login records by non-root user (aborting)"); 421 return (1); 422 } 423#endif 424 425 /* set the timestamp */ 426 login_set_current_time(li); 427#ifdef USE_LOGIN 428 syslogin_write_entry(li); 429#endif 430#ifdef USE_LASTLOG 431 if (li->type == LTYPE_LOGIN) 432 lastlog_write_entry(li); 433#endif 434#ifdef USE_UTMP 435 utmp_write_entry(li); 436#endif 437#ifdef USE_WTMP 438 wtmp_write_entry(li); 439#endif 440#ifdef USE_UTMPX 441 utmpx_write_entry(li); 442#endif 443#ifdef USE_WTMPX 444 wtmpx_write_entry(li); 445#endif 446#ifdef CUSTOM_SYS_AUTH_RECORD_LOGIN 447 if (li->type == LTYPE_LOGIN && 448 !sys_auth_record_login(li->username,li->hostname,li->line, 449 &loginmsg)) 450 logit("Writing login record failed for %s", li->username); 451#endif 452#ifdef SSH_AUDIT_EVENTS 453 if (li->type == LTYPE_LOGIN) 454 audit_session_open(li->line); 455 else if (li->type == LTYPE_LOGOUT) 456 audit_session_close(li->line); 457#endif 458 return (0); 459} 460 461#ifdef LOGIN_NEEDS_UTMPX 462int 463login_utmp_only(struct logininfo *li) 464{ 465 li->type = LTYPE_LOGIN; 466 login_set_current_time(li); 467# ifdef USE_UTMP 468 utmp_write_entry(li); 469# endif 470# ifdef USE_WTMP 471 wtmp_write_entry(li); 472# endif 473# ifdef USE_UTMPX 474 utmpx_write_entry(li); 475# endif 476# ifdef USE_WTMPX 477 wtmpx_write_entry(li); 478# endif 479 return (0); 480} 481#endif 482 483/** 484 ** getlast_entry: Call low-level functions to retrieve the last login 485 ** time. 486 **/ 487 488/* take the uid in li and return the last login time */ 489int 490getlast_entry(struct logininfo *li) 491{ 492#ifdef USE_LASTLOG 493 return(lastlog_get_entry(li)); 494#else /* !USE_LASTLOG */ 495 496#if defined(DISABLE_LASTLOG) 497 /* On some systems we shouldn't even try to obtain last login 498 * time, e.g. AIX */ 499 return (0); 500# elif defined(USE_WTMP) && \ 501 (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP)) 502 /* retrieve last login time from utmp */ 503 return (wtmp_get_entry(li)); 504# elif defined(USE_WTMPX) && \ 505 (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX)) 506 /* If wtmp isn't available, try wtmpx */ 507 return (wtmpx_get_entry(li)); 508# else 509 /* Give up: No means of retrieving last login time */ 510 return (0); 511# endif /* DISABLE_LASTLOG */ 512#endif /* USE_LASTLOG */ 513} 514 515 516 517/* 518 * 'line' string utility functions 519 * 520 * These functions process the 'line' string into one of three forms: 521 * 522 * 1. The full filename (including '/dev') 523 * 2. The stripped name (excluding '/dev') 524 * 3. The abbreviated name (e.g. /dev/ttyp00 -> yp00 525 * /dev/pts/1 -> ts/1 ) 526 * 527 * Form 3 is used on some systems to identify a .tmp.? entry when 528 * attempting to remove it. Typically both addition and removal is 529 * performed by one application - say, sshd - so as long as the choice 530 * uniquely identifies a terminal it's ok. 531 */ 532 533 534/* 535 * line_fullname(): add the leading '/dev/' if it doesn't exist make 536 * sure dst has enough space, if not just copy src (ugh) 537 */ 538char * 539line_fullname(char *dst, const char *src, u_int dstsize) 540{ 541 memset(dst, '\0', dstsize); 542 if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5))) 543 strlcpy(dst, src, dstsize); 544 else { 545 strlcpy(dst, "/dev/", dstsize); 546 strlcat(dst, src, dstsize); 547 } 548 return (dst); 549} 550 551/* line_stripname(): strip the leading '/dev' if it exists, return dst */ 552char * 553line_stripname(char *dst, const char *src, int dstsize) 554{ 555 memset(dst, '\0', dstsize); 556 if (strncmp(src, "/dev/", 5) == 0) 557 strlcpy(dst, src + 5, dstsize); 558 else 559 strlcpy(dst, src, dstsize); 560 return (dst); 561} 562 563/* 564 * line_abbrevname(): Return the abbreviated (usually four-character) 565 * form of the line (Just use the last <dstsize> characters of the 566 * full name.) 567 * 568 * NOTE: use strncpy because we do NOT necessarily want zero 569 * termination 570 */ 571char * 572line_abbrevname(char *dst, const char *src, int dstsize) 573{ 574 size_t len; 575 576 memset(dst, '\0', dstsize); 577 578 /* Always skip prefix if present */ 579 if (strncmp(src, "/dev/", 5) == 0) 580 src += 5; 581 582#ifdef WITH_ABBREV_NO_TTY 583 if (strncmp(src, "tty", 3) == 0) 584 src += 3; 585#endif 586 587 len = strlen(src); 588 589 if (len > 0) { 590 if (((int)len - dstsize) > 0) 591 src += ((int)len - dstsize); 592 593 /* note: _don't_ change this to strlcpy */ 594 strncpy(dst, src, (size_t)dstsize); 595 } 596 597 return (dst); 598} 599 600/** 601 ** utmp utility functions 602 ** 603 ** These functions manipulate struct utmp, taking system differences 604 ** into account. 605 **/ 606 607#if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN) 608 609/* build the utmp structure */ 610void 611set_utmp_time(struct logininfo *li, struct utmp *ut) 612{ 613# if defined(HAVE_TV_IN_UTMP) 614 ut->ut_tv.tv_sec = li->tv_sec; 615 ut->ut_tv.tv_usec = li->tv_usec; 616# elif defined(HAVE_TIME_IN_UTMP) 617 ut->ut_time = li->tv_sec; 618# endif 619} 620 621void 622construct_utmp(struct logininfo *li, 623 struct utmp *ut) 624{ 625# ifdef HAVE_ADDR_V6_IN_UTMP 626 struct sockaddr_in6 *sa6; 627# endif 628 629 memset(ut, '\0', sizeof(*ut)); 630 631 /* First fill out fields used for both logins and logouts */ 632 633# ifdef HAVE_ID_IN_UTMP 634 line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id)); 635# endif 636 637# ifdef HAVE_TYPE_IN_UTMP 638 /* This is done here to keep utmp constants out of struct logininfo */ 639 switch (li->type) { 640 case LTYPE_LOGIN: 641 ut->ut_type = USER_PROCESS; 642#ifdef _UNICOS 643 cray_set_tmpdir(ut); 644#endif 645 break; 646 case LTYPE_LOGOUT: 647 ut->ut_type = DEAD_PROCESS; 648#ifdef _UNICOS 649 cray_retain_utmp(ut, li->pid); 650#endif 651 break; 652 } 653# endif 654 set_utmp_time(li, ut); 655 656 line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line)); 657 658# ifdef HAVE_PID_IN_UTMP 659 ut->ut_pid = li->pid; 660# endif 661 662 /* If we're logging out, leave all other fields blank */ 663 if (li->type == LTYPE_LOGOUT) 664 return; 665 666 /* 667 * These fields are only used when logging in, and are blank 668 * for logouts. 669 */ 670 671 /* Use strncpy because we don't necessarily want null termination */ 672 strncpy(ut->ut_name, li->username, 673 MIN_SIZEOF(ut->ut_name, li->username)); 674# ifdef HAVE_HOST_IN_UTMP 675 realhostname_sa(ut->ut_host, sizeof ut->ut_host, 676 &li->hostaddr.sa, li->hostaddr.sa.sa_len); 677# endif 678# ifdef HAVE_ADDR_IN_UTMP 679 /* this is just a 32-bit IP address */ 680 if (li->hostaddr.sa.sa_family == AF_INET) 681 ut->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr; 682# endif 683# ifdef HAVE_ADDR_V6_IN_UTMP 684 /* this is just a 128-bit IPv6 address */ 685 if (li->hostaddr.sa.sa_family == AF_INET6) { 686 sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa); 687 memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16); 688 if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) { 689 ut->ut_addr_v6[0] = ut->ut_addr_v6[3]; 690 ut->ut_addr_v6[1] = 0; 691 ut->ut_addr_v6[2] = 0; 692 ut->ut_addr_v6[3] = 0; 693 } 694 } 695# endif 696} 697#endif /* USE_UTMP || USE_WTMP || USE_LOGIN */ 698 699/** 700 ** utmpx utility functions 701 ** 702 ** These functions manipulate struct utmpx, accounting for system 703 ** variations. 704 **/ 705 706#if defined(USE_UTMPX) || defined (USE_WTMPX) 707/* build the utmpx structure */ 708void 709set_utmpx_time(struct logininfo *li, struct utmpx *utx) 710{ 711# if defined(HAVE_TV_IN_UTMPX) 712 utx->ut_tv.tv_sec = li->tv_sec; 713 utx->ut_tv.tv_usec = li->tv_usec; 714# elif defined(HAVE_TIME_IN_UTMPX) 715 utx->ut_time = li->tv_sec; 716# endif 717} 718 719void 720construct_utmpx(struct logininfo *li, struct utmpx *utx) 721{ 722# ifdef HAVE_ADDR_V6_IN_UTMP 723 struct sockaddr_in6 *sa6; 724# endif 725 memset(utx, '\0', sizeof(*utx)); 726 727# ifdef HAVE_ID_IN_UTMPX 728 line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id)); 729# endif 730 731 /* this is done here to keep utmp constants out of loginrec.h */ 732 switch (li->type) { 733 case LTYPE_LOGIN: 734 utx->ut_type = USER_PROCESS; 735 break; 736 case LTYPE_LOGOUT: 737 utx->ut_type = DEAD_PROCESS; 738 break; 739 } 740 line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line)); 741 set_utmpx_time(li, utx); 742 utx->ut_pid = li->pid; 743 744 /* strncpy(): Don't necessarily want null termination */ 745 strncpy(utx->ut_name, li->username, 746 MIN_SIZEOF(utx->ut_name, li->username)); 747 748 if (li->type == LTYPE_LOGOUT) 749 return; 750 751 /* 752 * These fields are only used when logging in, and are blank 753 * for logouts. 754 */ 755 756# ifdef HAVE_HOST_IN_UTMPX 757 strncpy(utx->ut_host, li->hostname, 758 MIN_SIZEOF(utx->ut_host, li->hostname)); 759# endif 760# ifdef HAVE_ADDR_IN_UTMPX 761 /* this is just a 32-bit IP address */ 762 if (li->hostaddr.sa.sa_family == AF_INET) 763 utx->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr; 764# endif 765# ifdef HAVE_ADDR_V6_IN_UTMP 766 /* this is just a 128-bit IPv6 address */ 767 if (li->hostaddr.sa.sa_family == AF_INET6) { 768 sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa); 769 memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16); 770 if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) { 771 ut->ut_addr_v6[0] = ut->ut_addr_v6[3]; 772 ut->ut_addr_v6[1] = 0; 773 ut->ut_addr_v6[2] = 0; 774 ut->ut_addr_v6[3] = 0; 775 } 776 } 777# endif 778# ifdef HAVE_SYSLEN_IN_UTMPX 779 /* ut_syslen is the length of the utx_host string */ 780 utx->ut_syslen = MIN(strlen(li->hostname), sizeof(utx->ut_host)); 781# endif 782} 783#endif /* USE_UTMPX || USE_WTMPX */ 784 785/** 786 ** Low-level utmp functions 787 **/ 788 789/* FIXME: (ATL) utmp_write_direct needs testing */ 790#ifdef USE_UTMP 791 792/* if we can, use pututline() etc. */ 793# if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \ 794 defined(HAVE_PUTUTLINE) 795# define UTMP_USE_LIBRARY 796# endif 797 798 799/* write a utmp entry with the system's help (pututline() and pals) */ 800# ifdef UTMP_USE_LIBRARY 801static int 802utmp_write_library(struct logininfo *li, struct utmp *ut) 803{ 804 setutent(); 805 pututline(ut); 806# ifdef HAVE_ENDUTENT 807 endutent(); 808# endif 809 return (1); 810} 811# else /* UTMP_USE_LIBRARY */ 812 813/* 814 * Write a utmp entry direct to the file 815 * This is a slightly modification of code in OpenBSD's login.c 816 */ 817static int 818utmp_write_direct(struct logininfo *li, struct utmp *ut) 819{ 820 struct utmp old_ut; 821 register int fd; 822 int tty; 823 824 /* FIXME: (ATL) ttyslot() needs local implementation */ 825 826#if defined(HAVE_GETTTYENT) 827 struct ttyent *ty; 828 829 tty=0; 830 setttyent(); 831 while (NULL != (ty = getttyent())) { 832 tty++; 833 if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line))) 834 break; 835 } 836 endttyent(); 837 838 if (NULL == ty) { 839 logit("%s: tty not found", __func__); 840 return (0); 841 } 842#else /* FIXME */ 843 844 tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */ 845 846#endif /* HAVE_GETTTYENT */ 847 848 if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) { 849 off_t pos, ret; 850 851 pos = (off_t)tty * sizeof(struct utmp); 852 if ((ret = lseek(fd, pos, SEEK_SET)) == -1) { 853 logit("%s: lseek: %s", __func__, strerror(errno)); 854 return (0); 855 } 856 if (ret != pos) { 857 logit("%s: Couldn't seek to tty %d slot in %s", 858 __func__, tty, UTMP_FILE); 859 return (0); 860 } 861 /* 862 * Prevent luser from zero'ing out ut_host. 863 * If the new ut_line is empty but the old one is not 864 * and ut_line and ut_name match, preserve the old ut_line. 865 */ 866 if (atomicio(read, fd, &old_ut, sizeof(old_ut)) == sizeof(old_ut) && 867 (ut->ut_host[0] == '\0') && (old_ut.ut_host[0] != '\0') && 868 (strncmp(old_ut.ut_line, ut->ut_line, sizeof(ut->ut_line)) == 0) && 869 (strncmp(old_ut.ut_name, ut->ut_name, sizeof(ut->ut_name)) == 0)) 870 memcpy(ut->ut_host, old_ut.ut_host, sizeof(ut->ut_host)); 871 872 if ((ret = lseek(fd, pos, SEEK_SET)) == -1) { 873 logit("%s: lseek: %s", __func__, strerror(errno)); 874 return (0); 875 } 876 if (ret != pos) { 877 logit("%s: Couldn't seek to tty %d slot in %s", 878 __func__, tty, UTMP_FILE); 879 return (0); 880 } 881 if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) { 882 logit("%s: error writing %s: %s", __func__, 883 UTMP_FILE, strerror(errno)); 884 } 885 886 close(fd); 887 return (1); 888 } else { 889 return (0); 890 } 891} 892# endif /* UTMP_USE_LIBRARY */ 893 894static int 895utmp_perform_login(struct logininfo *li) 896{ 897 struct utmp ut; 898 899 construct_utmp(li, &ut); 900# ifdef UTMP_USE_LIBRARY 901 if (!utmp_write_library(li, &ut)) { 902 logit("%s: utmp_write_library() failed", __func__); 903 return (0); 904 } 905# else 906 if (!utmp_write_direct(li, &ut)) { 907 logit("%s: utmp_write_direct() failed", __func__); 908 return (0); 909 } 910# endif 911 return (1); 912} 913 914 915static int 916utmp_perform_logout(struct logininfo *li) 917{ 918 struct utmp ut; 919 920 construct_utmp(li, &ut); 921# ifdef UTMP_USE_LIBRARY 922 if (!utmp_write_library(li, &ut)) { 923 logit("%s: utmp_write_library() failed", __func__); 924 return (0); 925 } 926# else 927 if (!utmp_write_direct(li, &ut)) { 928 logit("%s: utmp_write_direct() failed", __func__); 929 return (0); 930 } 931# endif 932 return (1); 933} 934 935 936int 937utmp_write_entry(struct logininfo *li) 938{ 939 switch(li->type) { 940 case LTYPE_LOGIN: 941 return (utmp_perform_login(li)); 942 943 case LTYPE_LOGOUT: 944 return (utmp_perform_logout(li)); 945 946 default: 947 logit("%s: invalid type field", __func__); 948 return (0); 949 } 950} 951#endif /* USE_UTMP */ 952 953 954/** 955 ** Low-level utmpx functions 956 **/ 957 958/* not much point if we don't want utmpx entries */ 959#ifdef USE_UTMPX 960 961/* if we have the wherewithall, use pututxline etc. */ 962# if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) && \ 963 defined(HAVE_PUTUTXLINE) 964# define UTMPX_USE_LIBRARY 965# endif 966 967 968/* write a utmpx entry with the system's help (pututxline() and pals) */ 969# ifdef UTMPX_USE_LIBRARY 970static int 971utmpx_write_library(struct logininfo *li, struct utmpx *utx) 972{ 973 setutxent(); 974 pututxline(utx); 975 976# ifdef HAVE_ENDUTXENT 977 endutxent(); 978# endif 979 return (1); 980} 981 982# else /* UTMPX_USE_LIBRARY */ 983 984/* write a utmp entry direct to the file */ 985static int 986utmpx_write_direct(struct logininfo *li, struct utmpx *utx) 987{ 988 logit("%s: not implemented!", __func__); 989 return (0); 990} 991# endif /* UTMPX_USE_LIBRARY */ 992 993static int 994utmpx_perform_login(struct logininfo *li) 995{ 996 struct utmpx utx; 997 998 construct_utmpx(li, &utx); 999# ifdef UTMPX_USE_LIBRARY 1000 if (!utmpx_write_library(li, &utx)) { 1001 logit("%s: utmp_write_library() failed", __func__); 1002 return (0); 1003 } 1004# else 1005 if (!utmpx_write_direct(li, &ut)) { 1006 logit("%s: utmp_write_direct() failed", __func__); 1007 return (0); 1008 } 1009# endif 1010 return (1); 1011} 1012 1013 1014static int 1015utmpx_perform_logout(struct logininfo *li) 1016{ 1017 struct utmpx utx; 1018 1019 construct_utmpx(li, &utx); 1020# ifdef HAVE_ID_IN_UTMPX 1021 line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id)); 1022# endif 1023# ifdef HAVE_TYPE_IN_UTMPX 1024 utx.ut_type = DEAD_PROCESS; 1025# endif 1026 1027# ifdef UTMPX_USE_LIBRARY 1028 utmpx_write_library(li, &utx); 1029# else 1030 utmpx_write_direct(li, &utx); 1031# endif 1032 return (1); 1033} 1034 1035int 1036utmpx_write_entry(struct logininfo *li) 1037{ 1038 switch(li->type) { 1039 case LTYPE_LOGIN: 1040 return (utmpx_perform_login(li)); 1041 case LTYPE_LOGOUT: 1042 return (utmpx_perform_logout(li)); 1043 default: 1044 logit("%s: invalid type field", __func__); 1045 return (0); 1046 } 1047} 1048#endif /* USE_UTMPX */ 1049 1050 1051/** 1052 ** Low-level wtmp functions 1053 **/ 1054 1055#ifdef USE_WTMP 1056 1057/* 1058 * Write a wtmp entry direct to the end of the file 1059 * This is a slight modification of code in OpenBSD's logwtmp.c 1060 */ 1061static int 1062wtmp_write(struct logininfo *li, struct utmp *ut) 1063{ 1064 struct stat buf; 1065 int fd, ret = 1; 1066 1067 if ((fd = open(WTMP_FILE, O_WRONLY|O_APPEND, 0)) < 0) { 1068 logit("%s: problem writing %s: %s", __func__, 1069 WTMP_FILE, strerror(errno)); 1070 return (0); 1071 } 1072 if (fstat(fd, &buf) == 0) 1073 if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) { 1074 ftruncate(fd, buf.st_size); 1075 logit("%s: problem writing %s: %s", __func__, 1076 WTMP_FILE, strerror(errno)); 1077 ret = 0; 1078 } 1079 close(fd); 1080 return (ret); 1081} 1082 1083static int 1084wtmp_perform_login(struct logininfo *li) 1085{ 1086 struct utmp ut; 1087 1088 construct_utmp(li, &ut); 1089 return (wtmp_write(li, &ut)); 1090} 1091 1092 1093static int 1094wtmp_perform_logout(struct logininfo *li) 1095{ 1096 struct utmp ut; 1097 1098 construct_utmp(li, &ut); 1099 return (wtmp_write(li, &ut)); 1100} 1101 1102 1103int 1104wtmp_write_entry(struct logininfo *li) 1105{ 1106 switch(li->type) { 1107 case LTYPE_LOGIN: 1108 return (wtmp_perform_login(li)); 1109 case LTYPE_LOGOUT: 1110 return (wtmp_perform_logout(li)); 1111 default: 1112 logit("%s: invalid type field", __func__); 1113 return (0); 1114 } 1115} 1116 1117 1118/* 1119 * Notes on fetching login data from wtmp/wtmpx 1120 * 1121 * Logouts are usually recorded with (amongst other things) a blank 1122 * username on a given tty line. However, some systems (HP-UX is one) 1123 * leave all fields set, but change the ut_type field to DEAD_PROCESS. 1124 * 1125 * Since we're only looking for logins here, we know that the username 1126 * must be set correctly. On systems that leave it in, we check for 1127 * ut_type==USER_PROCESS (indicating a login.) 1128 * 1129 * Portability: Some systems may set something other than USER_PROCESS 1130 * to indicate a login process. I don't know of any as I write. Also, 1131 * it's possible that some systems may both leave the username in 1132 * place and not have ut_type. 1133 */ 1134 1135/* return true if this wtmp entry indicates a login */ 1136static int 1137wtmp_islogin(struct logininfo *li, struct utmp *ut) 1138{ 1139 if (strncmp(li->username, ut->ut_name, 1140 MIN_SIZEOF(li->username, ut->ut_name)) == 0) { 1141# ifdef HAVE_TYPE_IN_UTMP 1142 if (ut->ut_type & USER_PROCESS) 1143 return (1); 1144# else 1145 return (1); 1146# endif 1147 } 1148 return (0); 1149} 1150 1151int 1152wtmp_get_entry(struct logininfo *li) 1153{ 1154 struct stat st; 1155 struct utmp ut; 1156 int fd, found = 0; 1157 1158 /* Clear the time entries in our logininfo */ 1159 li->tv_sec = li->tv_usec = 0; 1160 1161 if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) { 1162 logit("%s: problem opening %s: %s", __func__, 1163 WTMP_FILE, strerror(errno)); 1164 return (0); 1165 } 1166 if (fstat(fd, &st) != 0) { 1167 logit("%s: couldn't stat %s: %s", __func__, 1168 WTMP_FILE, strerror(errno)); 1169 close(fd); 1170 return (0); 1171 } 1172 1173 /* Seek to the start of the last struct utmp */ 1174 if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) { 1175 /* Looks like we've got a fresh wtmp file */ 1176 close(fd); 1177 return (0); 1178 } 1179 1180 while (!found) { 1181 if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) { 1182 logit("%s: read of %s failed: %s", __func__, 1183 WTMP_FILE, strerror(errno)); 1184 close (fd); 1185 return (0); 1186 } 1187 if ( wtmp_islogin(li, &ut) ) { 1188 found = 1; 1189 /* 1190 * We've already checked for a time in struct 1191 * utmp, in login_getlast() 1192 */ 1193# ifdef HAVE_TIME_IN_UTMP 1194 li->tv_sec = ut.ut_time; 1195# else 1196# if HAVE_TV_IN_UTMP 1197 li->tv_sec = ut.ut_tv.tv_sec; 1198# endif 1199# endif 1200 line_fullname(li->line, ut.ut_line, 1201 MIN_SIZEOF(li->line, ut.ut_line)); 1202# ifdef HAVE_HOST_IN_UTMP 1203 strlcpy(li->hostname, ut.ut_host, 1204 MIN_SIZEOF(li->hostname, ut.ut_host)); 1205# endif 1206 continue; 1207 } 1208 /* Seek back 2 x struct utmp */ 1209 if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) { 1210 /* We've found the start of the file, so quit */ 1211 close(fd); 1212 return (0); 1213 } 1214 } 1215 1216 /* We found an entry. Tidy up and return */ 1217 close(fd); 1218 return (1); 1219} 1220# endif /* USE_WTMP */ 1221 1222 1223/** 1224 ** Low-level wtmpx functions 1225 **/ 1226 1227#ifdef USE_WTMPX 1228/* 1229 * Write a wtmpx entry direct to the end of the file 1230 * This is a slight modification of code in OpenBSD's logwtmp.c 1231 */ 1232static int 1233wtmpx_write(struct logininfo *li, struct utmpx *utx) 1234{ 1235#ifndef HAVE_UPDWTMPX 1236 struct stat buf; 1237 int fd, ret = 1; 1238 1239 if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) { 1240 logit("%s: problem opening %s: %s", __func__, 1241 WTMPX_FILE, strerror(errno)); 1242 return (0); 1243 } 1244 1245 if (fstat(fd, &buf) == 0) 1246 if (atomicio(vwrite, fd, utx, sizeof(*utx)) != sizeof(*utx)) { 1247 ftruncate(fd, buf.st_size); 1248 logit("%s: problem writing %s: %s", __func__, 1249 WTMPX_FILE, strerror(errno)); 1250 ret = 0; 1251 } 1252 close(fd); 1253 1254 return (ret); 1255#else 1256 updwtmpx(WTMPX_FILE, utx); 1257 return (1); 1258#endif 1259} 1260 1261 1262static int 1263wtmpx_perform_login(struct logininfo *li) 1264{ 1265 struct utmpx utx; 1266 1267 construct_utmpx(li, &utx); 1268 return (wtmpx_write(li, &utx)); 1269} 1270 1271 1272static int 1273wtmpx_perform_logout(struct logininfo *li) 1274{ 1275 struct utmpx utx; 1276 1277 construct_utmpx(li, &utx); 1278 return (wtmpx_write(li, &utx)); 1279} 1280 1281 1282int 1283wtmpx_write_entry(struct logininfo *li) 1284{ 1285 switch(li->type) { 1286 case LTYPE_LOGIN: 1287 return (wtmpx_perform_login(li)); 1288 case LTYPE_LOGOUT: 1289 return (wtmpx_perform_logout(li)); 1290 default: 1291 logit("%s: invalid type field", __func__); 1292 return (0); 1293 } 1294} 1295 1296/* Please see the notes above wtmp_islogin() for information about the 1297 next two functions */ 1298 1299/* Return true if this wtmpx entry indicates a login */ 1300static int 1301wtmpx_islogin(struct logininfo *li, struct utmpx *utx) 1302{ 1303 if (strncmp(li->username, utx->ut_name, 1304 MIN_SIZEOF(li->username, utx->ut_name)) == 0 ) { 1305# ifdef HAVE_TYPE_IN_UTMPX 1306 if (utx->ut_type == USER_PROCESS) 1307 return (1); 1308# else 1309 return (1); 1310# endif 1311 } 1312 return (0); 1313} 1314 1315 1316int 1317wtmpx_get_entry(struct logininfo *li) 1318{ 1319 struct stat st; 1320 struct utmpx utx; 1321 int fd, found=0; 1322 1323 /* Clear the time entries */ 1324 li->tv_sec = li->tv_usec = 0; 1325 1326 if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) { 1327 logit("%s: problem opening %s: %s", __func__, 1328 WTMPX_FILE, strerror(errno)); 1329 return (0); 1330 } 1331 if (fstat(fd, &st) != 0) { 1332 logit("%s: couldn't stat %s: %s", __func__, 1333 WTMPX_FILE, strerror(errno)); 1334 close(fd); 1335 return (0); 1336 } 1337 1338 /* Seek to the start of the last struct utmpx */ 1339 if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) { 1340 /* probably a newly rotated wtmpx file */ 1341 close(fd); 1342 return (0); 1343 } 1344 1345 while (!found) { 1346 if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) { 1347 logit("%s: read of %s failed: %s", __func__, 1348 WTMPX_FILE, strerror(errno)); 1349 close (fd); 1350 return (0); 1351 } 1352 /* 1353 * Logouts are recorded as a blank username on a particular 1354 * line. So, we just need to find the username in struct utmpx 1355 */ 1356 if (wtmpx_islogin(li, &utx)) { 1357 found = 1; 1358# if defined(HAVE_TV_IN_UTMPX) 1359 li->tv_sec = utx.ut_tv.tv_sec; 1360# elif defined(HAVE_TIME_IN_UTMPX) 1361 li->tv_sec = utx.ut_time; 1362# endif 1363 line_fullname(li->line, utx.ut_line, sizeof(li->line)); 1364# if defined(HAVE_HOST_IN_UTMPX) 1365 strlcpy(li->hostname, utx.ut_host, 1366 MIN_SIZEOF(li->hostname, utx.ut_host)); 1367# endif 1368 continue; 1369 } 1370 if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) { 1371 close(fd); 1372 return (0); 1373 } 1374 } 1375 1376 close(fd); 1377 return (1); 1378} 1379#endif /* USE_WTMPX */ 1380 1381/** 1382 ** Low-level libutil login() functions 1383 **/ 1384 1385#ifdef USE_LOGIN 1386static int 1387syslogin_perform_login(struct logininfo *li) 1388{ 1389 struct utmp *ut; 1390 1391 ut = xmalloc(sizeof(*ut)); 1392 construct_utmp(li, ut); 1393 login(ut); 1394 free(ut); 1395 1396 return (1); 1397} 1398 1399static int 1400syslogin_perform_logout(struct logininfo *li) 1401{ 1402# ifdef HAVE_LOGOUT 1403 char line[UT_LINESIZE]; 1404 1405 (void)line_stripname(line, li->line, sizeof(line)); 1406 1407 if (!logout(line)) 1408 logit("%s: logout() returned an error", __func__); 1409# ifdef HAVE_LOGWTMP 1410 else 1411 logwtmp(line, "", ""); 1412# endif 1413 /* FIXME: (ATL - if the need arises) What to do if we have 1414 * login, but no logout? what if logout but no logwtmp? All 1415 * routines are in libutil so they should all be there, 1416 * but... */ 1417# endif 1418 return (1); 1419} 1420 1421int 1422syslogin_write_entry(struct logininfo *li) 1423{ 1424 switch (li->type) { 1425 case LTYPE_LOGIN: 1426 return (syslogin_perform_login(li)); 1427 case LTYPE_LOGOUT: 1428 return (syslogin_perform_logout(li)); 1429 default: 1430 logit("%s: Invalid type field", __func__); 1431 return (0); 1432 } 1433} 1434#endif /* USE_LOGIN */ 1435 1436/* end of file log-syslogin.c */ 1437 1438/** 1439 ** Low-level lastlog functions 1440 **/ 1441 1442#ifdef USE_LASTLOG 1443#define LL_FILE 1 1444#define LL_DIR 2 1445#define LL_OTHER 3 1446 1447static void 1448lastlog_construct(struct logininfo *li, struct lastlog *last) 1449{ 1450 /* clear the structure */ 1451 memset(last, '\0', sizeof(*last)); 1452 1453 line_stripname(last->ll_line, li->line, sizeof(last->ll_line)); 1454 strlcpy(last->ll_host, li->hostname, 1455 MIN_SIZEOF(last->ll_host, li->hostname)); 1456 last->ll_time = li->tv_sec; 1457} 1458 1459static int 1460lastlog_filetype(char *filename) 1461{ 1462 struct stat st; 1463 1464 if (stat(LASTLOG_FILE, &st) != 0) { 1465 logit("%s: Couldn't stat %s: %s", __func__, 1466 LASTLOG_FILE, strerror(errno)); 1467 return (0); 1468 } 1469 if (S_ISDIR(st.st_mode)) 1470 return (LL_DIR); 1471 else if (S_ISREG(st.st_mode)) 1472 return (LL_FILE); 1473 else 1474 return (LL_OTHER); 1475} 1476 1477 1478/* open the file (using filemode) and seek to the login entry */ 1479static int 1480lastlog_openseek(struct logininfo *li, int *fd, int filemode) 1481{ 1482 off_t offset; 1483 int type; 1484 char lastlog_file[1024]; 1485 1486 type = lastlog_filetype(LASTLOG_FILE); 1487 switch (type) { 1488 case LL_FILE: 1489 strlcpy(lastlog_file, LASTLOG_FILE, 1490 sizeof(lastlog_file)); 1491 break; 1492 case LL_DIR: 1493 snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s", 1494 LASTLOG_FILE, li->username); 1495 break; 1496 default: 1497 logit("%s: %.100s is not a file or directory!", __func__, 1498 LASTLOG_FILE); 1499 return (0); 1500 } 1501 1502 *fd = open(lastlog_file, filemode, 0600); 1503 if (*fd < 0) { 1504 debug("%s: Couldn't open %s: %s", __func__, 1505 lastlog_file, strerror(errno)); 1506 return (0); 1507 } 1508 1509 if (type == LL_FILE) { 1510 /* find this uid's offset in the lastlog file */ 1511 offset = (off_t) ((long)li->uid * sizeof(struct lastlog)); 1512 1513 if (lseek(*fd, offset, SEEK_SET) != offset) { 1514 logit("%s: %s->lseek(): %s", __func__, 1515 lastlog_file, strerror(errno)); 1516 return (0); 1517 } 1518 } 1519 1520 return (1); 1521} 1522 1523static int 1524lastlog_perform_login(struct logininfo *li) 1525{ 1526 struct lastlog last; 1527 int fd; 1528 1529 /* create our struct lastlog */ 1530 lastlog_construct(li, &last); 1531 1532 if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT)) 1533 return (0); 1534 1535 /* write the entry */ 1536 if (atomicio(vwrite, fd, &last, sizeof(last)) != sizeof(last)) { 1537 close(fd); 1538 logit("%s: Error writing to %s: %s", __func__, 1539 LASTLOG_FILE, strerror(errno)); 1540 return (0); 1541 } 1542 1543 close(fd); 1544 return (1); 1545} 1546 1547int 1548lastlog_write_entry(struct logininfo *li) 1549{ 1550 switch(li->type) { 1551 case LTYPE_LOGIN: 1552 return (lastlog_perform_login(li)); 1553 default: 1554 logit("%s: Invalid type field", __func__); 1555 return (0); 1556 } 1557} 1558 1559static void 1560lastlog_populate_entry(struct logininfo *li, struct lastlog *last) 1561{ 1562 line_fullname(li->line, last->ll_line, sizeof(li->line)); 1563 strlcpy(li->hostname, last->ll_host, 1564 MIN_SIZEOF(li->hostname, last->ll_host)); 1565 li->tv_sec = last->ll_time; 1566} 1567 1568int 1569lastlog_get_entry(struct logininfo *li) 1570{ 1571 struct lastlog last; 1572 int fd, ret; 1573 1574 if (!lastlog_openseek(li, &fd, O_RDONLY)) 1575 return (0); 1576 1577 ret = atomicio(read, fd, &last, sizeof(last)); 1578 close(fd); 1579 1580 switch (ret) { 1581 case 0: 1582 memset(&last, '\0', sizeof(last)); 1583 /* FALLTHRU */ 1584 case sizeof(last): 1585 lastlog_populate_entry(li, &last); 1586 return (1); 1587 case -1: 1588 error("%s: Error reading from %s: %s", __func__, 1589 LASTLOG_FILE, strerror(errno)); 1590 return (0); 1591 default: 1592 error("%s: Error reading from %s: Expecting %d, got %d", 1593 __func__, LASTLOG_FILE, sizeof(last), ret); 1594 return (0); 1595 } 1596 1597 /* NOTREACHED */ 1598 return (0); 1599} 1600#endif /* USE_LASTLOG */ 1601 1602#ifdef USE_BTMP 1603 /* 1604 * Logs failed login attempts in _PATH_BTMP if that exists. 1605 * The most common login failure is to give password instead of username. 1606 * So the _PATH_BTMP file checked for the correct permission, so that 1607 * only root can read it. 1608 */ 1609 1610void 1611record_failed_login(const char *username, const char *hostname, 1612 const char *ttyn) 1613{ 1614 int fd; 1615 struct utmp ut; 1616 struct sockaddr_storage from; 1617 size_t fromlen = sizeof(from); 1618 struct sockaddr_in *a4; 1619 struct sockaddr_in6 *a6; 1620 time_t t; 1621 struct stat fst; 1622 1623 if (geteuid() != 0) 1624 return; 1625 if ((fd = open(_PATH_BTMP, O_WRONLY | O_APPEND)) < 0) { 1626 debug("Unable to open the btmp file %s: %s", _PATH_BTMP, 1627 strerror(errno)); 1628 return; 1629 } 1630 if (fstat(fd, &fst) < 0) { 1631 logit("%s: fstat of %s failed: %s", __func__, _PATH_BTMP, 1632 strerror(errno)); 1633 goto out; 1634 } 1635 if((fst.st_mode & (S_IRWXG | S_IRWXO)) || (fst.st_uid != 0)){ 1636 logit("Excess permission or bad ownership on file %s", 1637 _PATH_BTMP); 1638 goto out; 1639 } 1640 1641 memset(&ut, 0, sizeof(ut)); 1642 /* strncpy because we don't necessarily want nul termination */ 1643 strncpy(ut.ut_user, username, sizeof(ut.ut_user)); 1644 strlcpy(ut.ut_line, "ssh:notty", sizeof(ut.ut_line)); 1645 1646 time(&t); 1647 ut.ut_time = t; /* ut_time is not always a time_t */ 1648 ut.ut_type = LOGIN_PROCESS; 1649 ut.ut_pid = getpid(); 1650 1651 /* strncpy because we don't necessarily want nul termination */ 1652 strncpy(ut.ut_host, hostname, sizeof(ut.ut_host)); 1653 1654 if (packet_connection_is_on_socket() && 1655 getpeername(packet_get_connection_in(), 1656 (struct sockaddr *)&from, &fromlen) == 0) { 1657 ipv64_normalise_mapped(&from, &fromlen); 1658 if (from.ss_family == AF_INET) { 1659 a4 = (struct sockaddr_in *)&from; 1660 memcpy(&ut.ut_addr, &(a4->sin_addr), 1661 MIN_SIZEOF(ut.ut_addr, a4->sin_addr)); 1662 } 1663#ifdef HAVE_ADDR_V6_IN_UTMP 1664 if (from.ss_family == AF_INET6) { 1665 a6 = (struct sockaddr_in6 *)&from; 1666 memcpy(&ut.ut_addr_v6, &(a6->sin6_addr), 1667 MIN_SIZEOF(ut.ut_addr_v6, a6->sin6_addr)); 1668 } 1669#endif 1670 } 1671 1672 if (atomicio(vwrite, fd, &ut, sizeof(ut)) != sizeof(ut)) 1673 error("Failed to write to %s: %s", _PATH_BTMP, 1674 strerror(errno)); 1675 1676out: 1677 close(fd); 1678} 1679#endif /* USE_BTMP */ 1680