loginrec.c revision 184122
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 <sys/types.h> 151#include <sys/stat.h> 152#include <sys/socket.h> 153 154#include <netinet/in.h> 155 156#include <errno.h> 157#include <fcntl.h> 158#ifdef HAVE_PATHS_H 159# include <paths.h> 160#endif 161#include <pwd.h> 162#include <stdarg.h> 163#include <string.h> 164#include <time.h> 165#include <unistd.h> 166 167#include "xmalloc.h" 168#include "key.h" 169#include "hostfile.h" 170#include "ssh.h" 171#include "loginrec.h" 172#include "log.h" 173#include "atomicio.h" 174#include "packet.h" 175#include "canohost.h" 176#include "auth.h" 177#include "buffer.h" 178 179#ifdef HAVE_UTIL_H 180# include <util.h> 181#endif 182 183#ifdef HAVE_LIBUTIL_H 184# include <libutil.h> 185#endif 186 187/** 188 ** prototypes for helper functions in this file 189 **/ 190 191#if HAVE_UTMP_H 192void set_utmp_time(struct logininfo *li, struct utmp *ut); 193void construct_utmp(struct logininfo *li, struct utmp *ut); 194#endif 195 196#ifdef HAVE_UTMPX_H 197void set_utmpx_time(struct logininfo *li, struct utmpx *ut); 198void construct_utmpx(struct logininfo *li, struct utmpx *ut); 199#endif 200 201int utmp_write_entry(struct logininfo *li); 202int utmpx_write_entry(struct logininfo *li); 203int wtmp_write_entry(struct logininfo *li); 204int wtmpx_write_entry(struct logininfo *li); 205int lastlog_write_entry(struct logininfo *li); 206int syslogin_write_entry(struct logininfo *li); 207 208int getlast_entry(struct logininfo *li); 209int lastlog_get_entry(struct logininfo *li); 210int wtmp_get_entry(struct logininfo *li); 211int wtmpx_get_entry(struct logininfo *li); 212 213extern Buffer loginmsg; 214 215/* pick the shortest string */ 216#define MIN_SIZEOF(s1,s2) (sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2)) 217 218/** 219 ** platform-independent login functions 220 **/ 221 222/* 223 * login_login(struct logininfo *) - Record a login 224 * 225 * Call with a pointer to a struct logininfo initialised with 226 * login_init_entry() or login_alloc_entry() 227 * 228 * Returns: 229 * >0 if successful 230 * 0 on failure (will use OpenSSH's logging facilities for diagnostics) 231 */ 232int 233login_login(struct logininfo *li) 234{ 235 li->type = LTYPE_LOGIN; 236 return (login_write(li)); 237} 238 239 240/* 241 * login_logout(struct logininfo *) - Record a logout 242 * 243 * Call as with login_login() 244 * 245 * Returns: 246 * >0 if successful 247 * 0 on failure (will use OpenSSH's logging facilities for diagnostics) 248 */ 249int 250login_logout(struct logininfo *li) 251{ 252 li->type = LTYPE_LOGOUT; 253 return (login_write(li)); 254} 255 256/* 257 * login_get_lastlog_time(int) - Retrieve the last login time 258 * 259 * Retrieve the last login time for the given uid. Will try to use the 260 * system lastlog facilities if they are available, but will fall back 261 * to looking in wtmp/wtmpx if necessary 262 * 263 * Returns: 264 * 0 on failure, or if user has never logged in 265 * Time in seconds from the epoch if successful 266 * 267 * Useful preprocessor symbols: 268 * DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog 269 * info 270 * USE_LASTLOG: If set, indicates the presence of system lastlog 271 * facilities. If this and DISABLE_LASTLOG are not set, 272 * try to retrieve lastlog information from wtmp/wtmpx. 273 */ 274unsigned int 275login_get_lastlog_time(const int uid) 276{ 277 struct logininfo li; 278 279 if (login_get_lastlog(&li, uid)) 280 return (li.tv_sec); 281 else 282 return (0); 283} 284 285/* 286 * login_get_lastlog(struct logininfo *, int) - Retrieve a lastlog entry 287 * 288 * Retrieve a logininfo structure populated (only partially) with 289 * information from the system lastlog data, or from wtmp/wtmpx if no 290 * system lastlog information exists. 291 * 292 * Note this routine must be given a pre-allocated logininfo. 293 * 294 * Returns: 295 * >0: A pointer to your struct logininfo if successful 296 * 0 on failure (will use OpenSSH's logging facilities for diagnostics) 297 */ 298struct logininfo * 299login_get_lastlog(struct logininfo *li, const int uid) 300{ 301 struct passwd *pw; 302 303 memset(li, '\0', sizeof(*li)); 304 li->uid = uid; 305 306 /* 307 * If we don't have a 'real' lastlog, we need the username to 308 * reliably search wtmp(x) for the last login (see 309 * wtmp_get_entry().) 310 */ 311 pw = getpwuid(uid); 312 if (pw == NULL) 313 fatal("%s: Cannot find account for uid %i", __func__, uid); 314 315 /* No MIN_SIZEOF here - we absolutely *must not* truncate the 316 * username (XXX - so check for trunc!) */ 317 strlcpy(li->username, pw->pw_name, sizeof(li->username)); 318 319 if (getlast_entry(li)) 320 return (li); 321 else 322 return (NULL); 323} 324 325 326/* 327 * login_alloc_entry(int, char*, char*, char*) - Allocate and initialise 328 * a logininfo structure 329 * 330 * This function creates a new struct logininfo, a data structure 331 * meant to carry the information required to portably record login info. 332 * 333 * Returns a pointer to a newly created struct logininfo. If memory 334 * allocation fails, the program halts. 335 */ 336struct 337logininfo *login_alloc_entry(int pid, const char *username, 338 const char *hostname, const char *line) 339{ 340 struct logininfo *newli; 341 342 newli = xmalloc(sizeof(*newli)); 343 login_init_entry(newli, pid, username, hostname, line); 344 return (newli); 345} 346 347 348/* login_free_entry(struct logininfo *) - free struct memory */ 349void 350login_free_entry(struct logininfo *li) 351{ 352 xfree(li); 353} 354 355 356/* login_init_entry(struct logininfo *, int, char*, char*, char*) 357 * - initialise a struct logininfo 358 * 359 * Populates a new struct logininfo, a data structure meant to carry 360 * the information required to portably record login info. 361 * 362 * Returns: 1 363 */ 364int 365login_init_entry(struct logininfo *li, int pid, const char *username, 366 const char *hostname, const char *line) 367{ 368 struct passwd *pw; 369 370 memset(li, 0, sizeof(*li)); 371 372 li->pid = pid; 373 374 /* set the line information */ 375 if (line) 376 line_fullname(li->line, line, sizeof(li->line)); 377 378 if (username) { 379 strlcpy(li->username, username, sizeof(li->username)); 380 pw = getpwnam(li->username); 381 if (pw == NULL) { 382 fatal("%s: Cannot find user \"%s\"", __func__, 383 li->username); 384 } 385 li->uid = pw->pw_uid; 386 } 387 388 if (hostname) 389 strlcpy(li->hostname, hostname, sizeof(li->hostname)); 390 391 return (1); 392} 393 394/* 395 * login_set_current_time(struct logininfo *) - set the current time 396 * 397 * Set the current time in a logininfo structure. This function is 398 * meant to eliminate the need to deal with system dependencies for 399 * time handling. 400 */ 401void 402login_set_current_time(struct logininfo *li) 403{ 404 struct timeval tv; 405 406 gettimeofday(&tv, NULL); 407 408 li->tv_sec = tv.tv_sec; 409 li->tv_usec = tv.tv_usec; 410} 411 412/* copy a sockaddr_* into our logininfo */ 413void 414login_set_addr(struct logininfo *li, const struct sockaddr *sa, 415 const unsigned int sa_size) 416{ 417 unsigned int bufsize = sa_size; 418 419 /* make sure we don't overrun our union */ 420 if (sizeof(li->hostaddr) < sa_size) 421 bufsize = sizeof(li->hostaddr); 422 423 memcpy(&li->hostaddr.sa, sa, bufsize); 424} 425 426 427/** 428 ** login_write: Call low-level recording functions based on autoconf 429 ** results 430 **/ 431int 432login_write(struct logininfo *li) 433{ 434#ifndef HAVE_CYGWIN 435 if (geteuid() != 0) { 436 logit("Attempt to write login records by non-root user (aborting)"); 437 return (1); 438 } 439#endif 440 441 /* set the timestamp */ 442 login_set_current_time(li); 443#ifdef USE_LOGIN 444 syslogin_write_entry(li); 445#endif 446#ifdef USE_LASTLOG 447 if (li->type == LTYPE_LOGIN) 448 lastlog_write_entry(li); 449#endif 450#ifdef USE_UTMP 451 utmp_write_entry(li); 452#endif 453#ifdef USE_WTMP 454 wtmp_write_entry(li); 455#endif 456#ifdef USE_UTMPX 457 utmpx_write_entry(li); 458#endif 459#ifdef USE_WTMPX 460 wtmpx_write_entry(li); 461#endif 462#ifdef CUSTOM_SYS_AUTH_RECORD_LOGIN 463 if (li->type == LTYPE_LOGIN && 464 !sys_auth_record_login(li->username,li->hostname,li->line, 465 &loginmsg)) 466 logit("Writing login record failed for %s", li->username); 467#endif 468#ifdef SSH_AUDIT_EVENTS 469 if (li->type == LTYPE_LOGIN) 470 audit_session_open(li->line); 471 else if (li->type == LTYPE_LOGOUT) 472 audit_session_close(li->line); 473#endif 474 return (0); 475} 476 477#ifdef LOGIN_NEEDS_UTMPX 478int 479login_utmp_only(struct logininfo *li) 480{ 481 li->type = LTYPE_LOGIN; 482 login_set_current_time(li); 483# ifdef USE_UTMP 484 utmp_write_entry(li); 485# endif 486# ifdef USE_WTMP 487 wtmp_write_entry(li); 488# endif 489# ifdef USE_UTMPX 490 utmpx_write_entry(li); 491# endif 492# ifdef USE_WTMPX 493 wtmpx_write_entry(li); 494# endif 495 return (0); 496} 497#endif 498 499/** 500 ** getlast_entry: Call low-level functions to retrieve the last login 501 ** time. 502 **/ 503 504/* take the uid in li and return the last login time */ 505int 506getlast_entry(struct logininfo *li) 507{ 508#ifdef USE_LASTLOG 509 return(lastlog_get_entry(li)); 510#else /* !USE_LASTLOG */ 511 512#if defined(DISABLE_LASTLOG) 513 /* On some systems we shouldn't even try to obtain last login 514 * time, e.g. AIX */ 515 return (0); 516# elif defined(USE_WTMP) && \ 517 (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP)) 518 /* retrieve last login time from utmp */ 519 return (wtmp_get_entry(li)); 520# elif defined(USE_WTMPX) && \ 521 (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX)) 522 /* If wtmp isn't available, try wtmpx */ 523 return (wtmpx_get_entry(li)); 524# else 525 /* Give up: No means of retrieving last login time */ 526 return (0); 527# endif /* DISABLE_LASTLOG */ 528#endif /* USE_LASTLOG */ 529} 530 531 532 533/* 534 * 'line' string utility functions 535 * 536 * These functions process the 'line' string into one of three forms: 537 * 538 * 1. The full filename (including '/dev') 539 * 2. The stripped name (excluding '/dev') 540 * 3. The abbreviated name (e.g. /dev/ttyp00 -> yp00 541 * /dev/pts/1 -> ts/1 ) 542 * 543 * Form 3 is used on some systems to identify a .tmp.? entry when 544 * attempting to remove it. Typically both addition and removal is 545 * performed by one application - say, sshd - so as long as the choice 546 * uniquely identifies a terminal it's ok. 547 */ 548 549 550/* 551 * line_fullname(): add the leading '/dev/' if it doesn't exist make 552 * sure dst has enough space, if not just copy src (ugh) 553 */ 554char * 555line_fullname(char *dst, const char *src, u_int dstsize) 556{ 557 memset(dst, '\0', dstsize); 558 if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5))) 559 strlcpy(dst, src, dstsize); 560 else { 561 strlcpy(dst, "/dev/", dstsize); 562 strlcat(dst, src, dstsize); 563 } 564 return (dst); 565} 566 567/* line_stripname(): strip the leading '/dev' if it exists, return dst */ 568char * 569line_stripname(char *dst, const char *src, int dstsize) 570{ 571 memset(dst, '\0', dstsize); 572 if (strncmp(src, "/dev/", 5) == 0) 573 strlcpy(dst, src + 5, dstsize); 574 else 575 strlcpy(dst, src, dstsize); 576 return (dst); 577} 578 579/* 580 * line_abbrevname(): Return the abbreviated (usually four-character) 581 * form of the line (Just use the last <dstsize> characters of the 582 * full name.) 583 * 584 * NOTE: use strncpy because we do NOT necessarily want zero 585 * termination 586 */ 587char * 588line_abbrevname(char *dst, const char *src, int dstsize) 589{ 590 size_t len; 591 592 memset(dst, '\0', dstsize); 593 594 /* Always skip prefix if present */ 595 if (strncmp(src, "/dev/", 5) == 0) 596 src += 5; 597 598#ifdef WITH_ABBREV_NO_TTY 599 if (strncmp(src, "tty", 3) == 0) 600 src += 3; 601#endif 602 603 len = strlen(src); 604 605 if (len > 0) { 606 if (((int)len - dstsize) > 0) 607 src += ((int)len - dstsize); 608 609 /* note: _don't_ change this to strlcpy */ 610 strncpy(dst, src, (size_t)dstsize); 611 } 612 613 return (dst); 614} 615 616/** 617 ** utmp utility functions 618 ** 619 ** These functions manipulate struct utmp, taking system differences 620 ** into account. 621 **/ 622 623#if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN) 624 625/* build the utmp structure */ 626void 627set_utmp_time(struct logininfo *li, struct utmp *ut) 628{ 629# if defined(HAVE_TV_IN_UTMP) 630 ut->ut_tv.tv_sec = li->tv_sec; 631 ut->ut_tv.tv_usec = li->tv_usec; 632# elif defined(HAVE_TIME_IN_UTMP) 633 ut->ut_time = li->tv_sec; 634# endif 635} 636 637void 638construct_utmp(struct logininfo *li, 639 struct utmp *ut) 640{ 641# ifdef HAVE_ADDR_V6_IN_UTMP 642 struct sockaddr_in6 *sa6; 643# endif 644 645 memset(ut, '\0', sizeof(*ut)); 646 647 /* First fill out fields used for both logins and logouts */ 648 649# ifdef HAVE_ID_IN_UTMP 650 line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id)); 651# endif 652 653# ifdef HAVE_TYPE_IN_UTMP 654 /* This is done here to keep utmp constants out of struct logininfo */ 655 switch (li->type) { 656 case LTYPE_LOGIN: 657 ut->ut_type = USER_PROCESS; 658#ifdef _UNICOS 659 cray_set_tmpdir(ut); 660#endif 661 break; 662 case LTYPE_LOGOUT: 663 ut->ut_type = DEAD_PROCESS; 664#ifdef _UNICOS 665 cray_retain_utmp(ut, li->pid); 666#endif 667 break; 668 } 669# endif 670 set_utmp_time(li, ut); 671 672 line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line)); 673 674# ifdef HAVE_PID_IN_UTMP 675 ut->ut_pid = li->pid; 676# endif 677 678 /* If we're logging out, leave all other fields blank */ 679 if (li->type == LTYPE_LOGOUT) 680 return; 681 682 /* 683 * These fields are only used when logging in, and are blank 684 * for logouts. 685 */ 686 687 /* Use strncpy because we don't necessarily want null termination */ 688 strncpy(ut->ut_name, li->username, 689 MIN_SIZEOF(ut->ut_name, li->username)); 690# ifdef HAVE_HOST_IN_UTMP 691 strncpy(ut->ut_host, li->hostname, 692 MIN_SIZEOF(ut->ut_host, li->hostname)); 693# endif 694# ifdef HAVE_ADDR_IN_UTMP 695 /* this is just a 32-bit IP address */ 696 if (li->hostaddr.sa.sa_family == AF_INET) 697 ut->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr; 698# endif 699# ifdef HAVE_ADDR_V6_IN_UTMP 700 /* this is just a 128-bit IPv6 address */ 701 if (li->hostaddr.sa.sa_family == AF_INET6) { 702 sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa); 703 memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16); 704 if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) { 705 ut->ut_addr_v6[0] = ut->ut_addr_v6[3]; 706 ut->ut_addr_v6[1] = 0; 707 ut->ut_addr_v6[2] = 0; 708 ut->ut_addr_v6[3] = 0; 709 } 710 } 711# endif 712} 713#endif /* USE_UTMP || USE_WTMP || USE_LOGIN */ 714 715/** 716 ** utmpx utility functions 717 ** 718 ** These functions manipulate struct utmpx, accounting for system 719 ** variations. 720 **/ 721 722#if defined(USE_UTMPX) || defined (USE_WTMPX) 723/* build the utmpx structure */ 724void 725set_utmpx_time(struct logininfo *li, struct utmpx *utx) 726{ 727# if defined(HAVE_TV_IN_UTMPX) 728 utx->ut_tv.tv_sec = li->tv_sec; 729 utx->ut_tv.tv_usec = li->tv_usec; 730# elif defined(HAVE_TIME_IN_UTMPX) 731 utx->ut_time = li->tv_sec; 732# endif 733} 734 735void 736construct_utmpx(struct logininfo *li, struct utmpx *utx) 737{ 738# ifdef HAVE_ADDR_V6_IN_UTMP 739 struct sockaddr_in6 *sa6; 740# endif 741 memset(utx, '\0', sizeof(*utx)); 742 743# ifdef HAVE_ID_IN_UTMPX 744 line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id)); 745# endif 746 747 /* this is done here to keep utmp constants out of loginrec.h */ 748 switch (li->type) { 749 case LTYPE_LOGIN: 750 utx->ut_type = USER_PROCESS; 751 break; 752 case LTYPE_LOGOUT: 753 utx->ut_type = DEAD_PROCESS; 754 break; 755 } 756 line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line)); 757 set_utmpx_time(li, utx); 758 utx->ut_pid = li->pid; 759 760 /* strncpy(): Don't necessarily want null termination */ 761 strncpy(utx->ut_name, li->username, 762 MIN_SIZEOF(utx->ut_name, li->username)); 763 764 if (li->type == LTYPE_LOGOUT) 765 return; 766 767 /* 768 * These fields are only used when logging in, and are blank 769 * for logouts. 770 */ 771 772# ifdef HAVE_HOST_IN_UTMPX 773 strncpy(utx->ut_host, li->hostname, 774 MIN_SIZEOF(utx->ut_host, li->hostname)); 775# endif 776# ifdef HAVE_ADDR_IN_UTMPX 777 /* this is just a 32-bit IP address */ 778 if (li->hostaddr.sa.sa_family == AF_INET) 779 utx->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr; 780# endif 781# ifdef HAVE_ADDR_V6_IN_UTMP 782 /* this is just a 128-bit IPv6 address */ 783 if (li->hostaddr.sa.sa_family == AF_INET6) { 784 sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa); 785 memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16); 786 if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) { 787 ut->ut_addr_v6[0] = ut->ut_addr_v6[3]; 788 ut->ut_addr_v6[1] = 0; 789 ut->ut_addr_v6[2] = 0; 790 ut->ut_addr_v6[3] = 0; 791 } 792 } 793# endif 794# ifdef HAVE_SYSLEN_IN_UTMPX 795 /* ut_syslen is the length of the utx_host string */ 796 utx->ut_syslen = MIN(strlen(li->hostname), sizeof(utx->ut_host)); 797# endif 798} 799#endif /* USE_UTMPX || USE_WTMPX */ 800 801/** 802 ** Low-level utmp functions 803 **/ 804 805/* FIXME: (ATL) utmp_write_direct needs testing */ 806#ifdef USE_UTMP 807 808/* if we can, use pututline() etc. */ 809# if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \ 810 defined(HAVE_PUTUTLINE) 811# define UTMP_USE_LIBRARY 812# endif 813 814 815/* write a utmp entry with the system's help (pututline() and pals) */ 816# ifdef UTMP_USE_LIBRARY 817static int 818utmp_write_library(struct logininfo *li, struct utmp *ut) 819{ 820 setutent(); 821 pututline(ut); 822# ifdef HAVE_ENDUTENT 823 endutent(); 824# endif 825 return (1); 826} 827# else /* UTMP_USE_LIBRARY */ 828 829/* 830 * Write a utmp entry direct to the file 831 * This is a slightly modification of code in OpenBSD's login.c 832 */ 833static int 834utmp_write_direct(struct logininfo *li, struct utmp *ut) 835{ 836 struct utmp old_ut; 837 register int fd; 838 int tty; 839 840 /* FIXME: (ATL) ttyslot() needs local implementation */ 841 842#if defined(HAVE_GETTTYENT) 843 struct ttyent *ty; 844 845 tty=0; 846 setttyent(); 847 while (NULL != (ty = getttyent())) { 848 tty++; 849 if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line))) 850 break; 851 } 852 endttyent(); 853 854 if (NULL == ty) { 855 logit("%s: tty not found", __func__); 856 return (0); 857 } 858#else /* FIXME */ 859 860 tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */ 861 862#endif /* HAVE_GETTTYENT */ 863 864 if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) { 865 off_t pos, ret; 866 867 pos = (off_t)tty * sizeof(struct utmp); 868 if ((ret = lseek(fd, pos, SEEK_SET)) == -1) { 869 logit("%s: lseek: %s", __func__, strerror(errno)); 870 return (0); 871 } 872 if (ret != pos) { 873 logit("%s: Couldn't seek to tty %d slot in %s", 874 __func__, tty, UTMP_FILE); 875 return (0); 876 } 877 /* 878 * Prevent luser from zero'ing out ut_host. 879 * If the new ut_line is empty but the old one is not 880 * and ut_line and ut_name match, preserve the old ut_line. 881 */ 882 if (atomicio(read, fd, &old_ut, sizeof(old_ut)) == sizeof(old_ut) && 883 (ut->ut_host[0] == '\0') && (old_ut.ut_host[0] != '\0') && 884 (strncmp(old_ut.ut_line, ut->ut_line, sizeof(ut->ut_line)) == 0) && 885 (strncmp(old_ut.ut_name, ut->ut_name, sizeof(ut->ut_name)) == 0)) 886 memcpy(ut->ut_host, old_ut.ut_host, sizeof(ut->ut_host)); 887 888 if ((ret = lseek(fd, pos, SEEK_SET)) == -1) { 889 logit("%s: lseek: %s", __func__, strerror(errno)); 890 return (0); 891 } 892 if (ret != pos) { 893 logit("%s: Couldn't seek to tty %d slot in %s", 894 __func__, tty, UTMP_FILE); 895 return (0); 896 } 897 if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) { 898 logit("%s: error writing %s: %s", __func__, 899 UTMP_FILE, strerror(errno)); 900 } 901 902 close(fd); 903 return (1); 904 } else { 905 return (0); 906 } 907} 908# endif /* UTMP_USE_LIBRARY */ 909 910static int 911utmp_perform_login(struct logininfo *li) 912{ 913 struct utmp ut; 914 915 construct_utmp(li, &ut); 916# ifdef UTMP_USE_LIBRARY 917 if (!utmp_write_library(li, &ut)) { 918 logit("%s: utmp_write_library() failed", __func__); 919 return (0); 920 } 921# else 922 if (!utmp_write_direct(li, &ut)) { 923 logit("%s: utmp_write_direct() failed", __func__); 924 return (0); 925 } 926# endif 927 return (1); 928} 929 930 931static int 932utmp_perform_logout(struct logininfo *li) 933{ 934 struct utmp ut; 935 936 construct_utmp(li, &ut); 937# ifdef UTMP_USE_LIBRARY 938 if (!utmp_write_library(li, &ut)) { 939 logit("%s: utmp_write_library() failed", __func__); 940 return (0); 941 } 942# else 943 if (!utmp_write_direct(li, &ut)) { 944 logit("%s: utmp_write_direct() failed", __func__); 945 return (0); 946 } 947# endif 948 return (1); 949} 950 951 952int 953utmp_write_entry(struct logininfo *li) 954{ 955 switch(li->type) { 956 case LTYPE_LOGIN: 957 return (utmp_perform_login(li)); 958 959 case LTYPE_LOGOUT: 960 return (utmp_perform_logout(li)); 961 962 default: 963 logit("%s: invalid type field", __func__); 964 return (0); 965 } 966} 967#endif /* USE_UTMP */ 968 969 970/** 971 ** Low-level utmpx functions 972 **/ 973 974/* not much point if we don't want utmpx entries */ 975#ifdef USE_UTMPX 976 977/* if we have the wherewithall, use pututxline etc. */ 978# if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) && \ 979 defined(HAVE_PUTUTXLINE) 980# define UTMPX_USE_LIBRARY 981# endif 982 983 984/* write a utmpx entry with the system's help (pututxline() and pals) */ 985# ifdef UTMPX_USE_LIBRARY 986static int 987utmpx_write_library(struct logininfo *li, struct utmpx *utx) 988{ 989 setutxent(); 990 pututxline(utx); 991 992# ifdef HAVE_ENDUTXENT 993 endutxent(); 994# endif 995 return (1); 996} 997 998# else /* UTMPX_USE_LIBRARY */ 999 1000/* write a utmp entry direct to the file */ 1001static int 1002utmpx_write_direct(struct logininfo *li, struct utmpx *utx) 1003{ 1004 logit("%s: not implemented!", __func__); 1005 return (0); 1006} 1007# endif /* UTMPX_USE_LIBRARY */ 1008 1009static int 1010utmpx_perform_login(struct logininfo *li) 1011{ 1012 struct utmpx utx; 1013 1014 construct_utmpx(li, &utx); 1015# ifdef UTMPX_USE_LIBRARY 1016 if (!utmpx_write_library(li, &utx)) { 1017 logit("%s: utmp_write_library() failed", __func__); 1018 return (0); 1019 } 1020# else 1021 if (!utmpx_write_direct(li, &ut)) { 1022 logit("%s: utmp_write_direct() failed", __func__); 1023 return (0); 1024 } 1025# endif 1026 return (1); 1027} 1028 1029 1030static int 1031utmpx_perform_logout(struct logininfo *li) 1032{ 1033 struct utmpx utx; 1034 1035 construct_utmpx(li, &utx); 1036# ifdef HAVE_ID_IN_UTMPX 1037 line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id)); 1038# endif 1039# ifdef HAVE_TYPE_IN_UTMPX 1040 utx.ut_type = DEAD_PROCESS; 1041# endif 1042 1043# ifdef UTMPX_USE_LIBRARY 1044 utmpx_write_library(li, &utx); 1045# else 1046 utmpx_write_direct(li, &utx); 1047# endif 1048 return (1); 1049} 1050 1051int 1052utmpx_write_entry(struct logininfo *li) 1053{ 1054 switch(li->type) { 1055 case LTYPE_LOGIN: 1056 return (utmpx_perform_login(li)); 1057 case LTYPE_LOGOUT: 1058 return (utmpx_perform_logout(li)); 1059 default: 1060 logit("%s: invalid type field", __func__); 1061 return (0); 1062 } 1063} 1064#endif /* USE_UTMPX */ 1065 1066 1067/** 1068 ** Low-level wtmp functions 1069 **/ 1070 1071#ifdef USE_WTMP 1072 1073/* 1074 * Write a wtmp entry direct to the end of the file 1075 * This is a slight modification of code in OpenBSD's logwtmp.c 1076 */ 1077static int 1078wtmp_write(struct logininfo *li, struct utmp *ut) 1079{ 1080 struct stat buf; 1081 int fd, ret = 1; 1082 1083 if ((fd = open(WTMP_FILE, O_WRONLY|O_APPEND, 0)) < 0) { 1084 logit("%s: problem writing %s: %s", __func__, 1085 WTMP_FILE, strerror(errno)); 1086 return (0); 1087 } 1088 if (fstat(fd, &buf) == 0) 1089 if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) { 1090 ftruncate(fd, buf.st_size); 1091 logit("%s: problem writing %s: %s", __func__, 1092 WTMP_FILE, strerror(errno)); 1093 ret = 0; 1094 } 1095 close(fd); 1096 return (ret); 1097} 1098 1099static int 1100wtmp_perform_login(struct logininfo *li) 1101{ 1102 struct utmp ut; 1103 1104 construct_utmp(li, &ut); 1105 return (wtmp_write(li, &ut)); 1106} 1107 1108 1109static int 1110wtmp_perform_logout(struct logininfo *li) 1111{ 1112 struct utmp ut; 1113 1114 construct_utmp(li, &ut); 1115 return (wtmp_write(li, &ut)); 1116} 1117 1118 1119int 1120wtmp_write_entry(struct logininfo *li) 1121{ 1122 switch(li->type) { 1123 case LTYPE_LOGIN: 1124 return (wtmp_perform_login(li)); 1125 case LTYPE_LOGOUT: 1126 return (wtmp_perform_logout(li)); 1127 default: 1128 logit("%s: invalid type field", __func__); 1129 return (0); 1130 } 1131} 1132 1133 1134/* 1135 * Notes on fetching login data from wtmp/wtmpx 1136 * 1137 * Logouts are usually recorded with (amongst other things) a blank 1138 * username on a given tty line. However, some systems (HP-UX is one) 1139 * leave all fields set, but change the ut_type field to DEAD_PROCESS. 1140 * 1141 * Since we're only looking for logins here, we know that the username 1142 * must be set correctly. On systems that leave it in, we check for 1143 * ut_type==USER_PROCESS (indicating a login.) 1144 * 1145 * Portability: Some systems may set something other than USER_PROCESS 1146 * to indicate a login process. I don't know of any as I write. Also, 1147 * it's possible that some systems may both leave the username in 1148 * place and not have ut_type. 1149 */ 1150 1151/* return true if this wtmp entry indicates a login */ 1152static int 1153wtmp_islogin(struct logininfo *li, struct utmp *ut) 1154{ 1155 if (strncmp(li->username, ut->ut_name, 1156 MIN_SIZEOF(li->username, ut->ut_name)) == 0) { 1157# ifdef HAVE_TYPE_IN_UTMP 1158 if (ut->ut_type & USER_PROCESS) 1159 return (1); 1160# else 1161 return (1); 1162# endif 1163 } 1164 return (0); 1165} 1166 1167int 1168wtmp_get_entry(struct logininfo *li) 1169{ 1170 struct stat st; 1171 struct utmp ut; 1172 int fd, found = 0; 1173 1174 /* Clear the time entries in our logininfo */ 1175 li->tv_sec = li->tv_usec = 0; 1176 1177 if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) { 1178 logit("%s: problem opening %s: %s", __func__, 1179 WTMP_FILE, strerror(errno)); 1180 return (0); 1181 } 1182 if (fstat(fd, &st) != 0) { 1183 logit("%s: couldn't stat %s: %s", __func__, 1184 WTMP_FILE, strerror(errno)); 1185 close(fd); 1186 return (0); 1187 } 1188 1189 /* Seek to the start of the last struct utmp */ 1190 if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) { 1191 /* Looks like we've got a fresh wtmp file */ 1192 close(fd); 1193 return (0); 1194 } 1195 1196 while (!found) { 1197 if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) { 1198 logit("%s: read of %s failed: %s", __func__, 1199 WTMP_FILE, strerror(errno)); 1200 close (fd); 1201 return (0); 1202 } 1203 if ( wtmp_islogin(li, &ut) ) { 1204 found = 1; 1205 /* 1206 * We've already checked for a time in struct 1207 * utmp, in login_getlast() 1208 */ 1209# ifdef HAVE_TIME_IN_UTMP 1210 li->tv_sec = ut.ut_time; 1211# else 1212# if HAVE_TV_IN_UTMP 1213 li->tv_sec = ut.ut_tv.tv_sec; 1214# endif 1215# endif 1216 line_fullname(li->line, ut.ut_line, 1217 MIN_SIZEOF(li->line, ut.ut_line)); 1218# ifdef HAVE_HOST_IN_UTMP 1219 strlcpy(li->hostname, ut.ut_host, 1220 MIN_SIZEOF(li->hostname, ut.ut_host)); 1221# endif 1222 continue; 1223 } 1224 /* Seek back 2 x struct utmp */ 1225 if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) { 1226 /* We've found the start of the file, so quit */ 1227 close(fd); 1228 return (0); 1229 } 1230 } 1231 1232 /* We found an entry. Tidy up and return */ 1233 close(fd); 1234 return (1); 1235} 1236# endif /* USE_WTMP */ 1237 1238 1239/** 1240 ** Low-level wtmpx functions 1241 **/ 1242 1243#ifdef USE_WTMPX 1244/* 1245 * Write a wtmpx entry direct to the end of the file 1246 * This is a slight modification of code in OpenBSD's logwtmp.c 1247 */ 1248static int 1249wtmpx_write(struct logininfo *li, struct utmpx *utx) 1250{ 1251#ifndef HAVE_UPDWTMPX 1252 struct stat buf; 1253 int fd, ret = 1; 1254 1255 if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) { 1256 logit("%s: problem opening %s: %s", __func__, 1257 WTMPX_FILE, strerror(errno)); 1258 return (0); 1259 } 1260 1261 if (fstat(fd, &buf) == 0) 1262 if (atomicio(vwrite, fd, utx, sizeof(*utx)) != sizeof(*utx)) { 1263 ftruncate(fd, buf.st_size); 1264 logit("%s: problem writing %s: %s", __func__, 1265 WTMPX_FILE, strerror(errno)); 1266 ret = 0; 1267 } 1268 close(fd); 1269 1270 return (ret); 1271#else 1272 updwtmpx(WTMPX_FILE, utx); 1273 return (1); 1274#endif 1275} 1276 1277 1278static int 1279wtmpx_perform_login(struct logininfo *li) 1280{ 1281 struct utmpx utx; 1282 1283 construct_utmpx(li, &utx); 1284 return (wtmpx_write(li, &utx)); 1285} 1286 1287 1288static int 1289wtmpx_perform_logout(struct logininfo *li) 1290{ 1291 struct utmpx utx; 1292 1293 construct_utmpx(li, &utx); 1294 return (wtmpx_write(li, &utx)); 1295} 1296 1297 1298int 1299wtmpx_write_entry(struct logininfo *li) 1300{ 1301 switch(li->type) { 1302 case LTYPE_LOGIN: 1303 return (wtmpx_perform_login(li)); 1304 case LTYPE_LOGOUT: 1305 return (wtmpx_perform_logout(li)); 1306 default: 1307 logit("%s: invalid type field", __func__); 1308 return (0); 1309 } 1310} 1311 1312/* Please see the notes above wtmp_islogin() for information about the 1313 next two functions */ 1314 1315/* Return true if this wtmpx entry indicates a login */ 1316static int 1317wtmpx_islogin(struct logininfo *li, struct utmpx *utx) 1318{ 1319 if (strncmp(li->username, utx->ut_name, 1320 MIN_SIZEOF(li->username, utx->ut_name)) == 0 ) { 1321# ifdef HAVE_TYPE_IN_UTMPX 1322 if (utx->ut_type == USER_PROCESS) 1323 return (1); 1324# else 1325 return (1); 1326# endif 1327 } 1328 return (0); 1329} 1330 1331 1332int 1333wtmpx_get_entry(struct logininfo *li) 1334{ 1335 struct stat st; 1336 struct utmpx utx; 1337 int fd, found=0; 1338 1339 /* Clear the time entries */ 1340 li->tv_sec = li->tv_usec = 0; 1341 1342 if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) { 1343 logit("%s: problem opening %s: %s", __func__, 1344 WTMPX_FILE, strerror(errno)); 1345 return (0); 1346 } 1347 if (fstat(fd, &st) != 0) { 1348 logit("%s: couldn't stat %s: %s", __func__, 1349 WTMPX_FILE, strerror(errno)); 1350 close(fd); 1351 return (0); 1352 } 1353 1354 /* Seek to the start of the last struct utmpx */ 1355 if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) { 1356 /* probably a newly rotated wtmpx file */ 1357 close(fd); 1358 return (0); 1359 } 1360 1361 while (!found) { 1362 if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) { 1363 logit("%s: read of %s failed: %s", __func__, 1364 WTMPX_FILE, strerror(errno)); 1365 close (fd); 1366 return (0); 1367 } 1368 /* 1369 * Logouts are recorded as a blank username on a particular 1370 * line. So, we just need to find the username in struct utmpx 1371 */ 1372 if (wtmpx_islogin(li, &utx)) { 1373 found = 1; 1374# if defined(HAVE_TV_IN_UTMPX) 1375 li->tv_sec = utx.ut_tv.tv_sec; 1376# elif defined(HAVE_TIME_IN_UTMPX) 1377 li->tv_sec = utx.ut_time; 1378# endif 1379 line_fullname(li->line, utx.ut_line, sizeof(li->line)); 1380# if defined(HAVE_HOST_IN_UTMPX) 1381 strlcpy(li->hostname, utx.ut_host, 1382 MIN_SIZEOF(li->hostname, utx.ut_host)); 1383# endif 1384 continue; 1385 } 1386 if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) { 1387 close(fd); 1388 return (0); 1389 } 1390 } 1391 1392 close(fd); 1393 return (1); 1394} 1395#endif /* USE_WTMPX */ 1396 1397/** 1398 ** Low-level libutil login() functions 1399 **/ 1400 1401#ifdef USE_LOGIN 1402static int 1403syslogin_perform_login(struct logininfo *li) 1404{ 1405 struct utmp *ut; 1406 1407 ut = xmalloc(sizeof(*ut)); 1408 construct_utmp(li, ut); 1409 login(ut); 1410 free(ut); 1411 1412 return (1); 1413} 1414 1415static int 1416syslogin_perform_logout(struct logininfo *li) 1417{ 1418# ifdef HAVE_LOGOUT 1419 char line[UT_LINESIZE]; 1420 1421 (void)line_stripname(line, li->line, sizeof(line)); 1422 1423 if (!logout(line)) 1424 logit("%s: logout() returned an error", __func__); 1425# ifdef HAVE_LOGWTMP 1426 else 1427 logwtmp(line, "", ""); 1428# endif 1429 /* FIXME: (ATL - if the need arises) What to do if we have 1430 * login, but no logout? what if logout but no logwtmp? All 1431 * routines are in libutil so they should all be there, 1432 * but... */ 1433# endif 1434 return (1); 1435} 1436 1437int 1438syslogin_write_entry(struct logininfo *li) 1439{ 1440 switch (li->type) { 1441 case LTYPE_LOGIN: 1442 return (syslogin_perform_login(li)); 1443 case LTYPE_LOGOUT: 1444 return (syslogin_perform_logout(li)); 1445 default: 1446 logit("%s: Invalid type field", __func__); 1447 return (0); 1448 } 1449} 1450#endif /* USE_LOGIN */ 1451 1452/* end of file log-syslogin.c */ 1453 1454/** 1455 ** Low-level lastlog functions 1456 **/ 1457 1458#ifdef USE_LASTLOG 1459#define LL_FILE 1 1460#define LL_DIR 2 1461#define LL_OTHER 3 1462 1463static void 1464lastlog_construct(struct logininfo *li, struct lastlog *last) 1465{ 1466 /* clear the structure */ 1467 memset(last, '\0', sizeof(*last)); 1468 1469 line_stripname(last->ll_line, li->line, sizeof(last->ll_line)); 1470 strlcpy(last->ll_host, li->hostname, 1471 MIN_SIZEOF(last->ll_host, li->hostname)); 1472 last->ll_time = li->tv_sec; 1473} 1474 1475static int 1476lastlog_filetype(char *filename) 1477{ 1478 struct stat st; 1479 1480 if (stat(LASTLOG_FILE, &st) != 0) { 1481 logit("%s: Couldn't stat %s: %s", __func__, 1482 LASTLOG_FILE, strerror(errno)); 1483 return (0); 1484 } 1485 if (S_ISDIR(st.st_mode)) 1486 return (LL_DIR); 1487 else if (S_ISREG(st.st_mode)) 1488 return (LL_FILE); 1489 else 1490 return (LL_OTHER); 1491} 1492 1493 1494/* open the file (using filemode) and seek to the login entry */ 1495static int 1496lastlog_openseek(struct logininfo *li, int *fd, int filemode) 1497{ 1498 off_t offset; 1499 int type; 1500 char lastlog_file[1024]; 1501 1502 type = lastlog_filetype(LASTLOG_FILE); 1503 switch (type) { 1504 case LL_FILE: 1505 strlcpy(lastlog_file, LASTLOG_FILE, 1506 sizeof(lastlog_file)); 1507 break; 1508 case LL_DIR: 1509 snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s", 1510 LASTLOG_FILE, li->username); 1511 break; 1512 default: 1513 logit("%s: %.100s is not a file or directory!", __func__, 1514 LASTLOG_FILE); 1515 return (0); 1516 } 1517 1518 *fd = open(lastlog_file, filemode, 0600); 1519 if (*fd < 0) { 1520 debug("%s: Couldn't open %s: %s", __func__, 1521 lastlog_file, strerror(errno)); 1522 return (0); 1523 } 1524 1525 if (type == LL_FILE) { 1526 /* find this uid's offset in the lastlog file */ 1527 offset = (off_t) ((long)li->uid * sizeof(struct lastlog)); 1528 1529 if (lseek(*fd, offset, SEEK_SET) != offset) { 1530 logit("%s: %s->lseek(): %s", __func__, 1531 lastlog_file, strerror(errno)); 1532 return (0); 1533 } 1534 } 1535 1536 return (1); 1537} 1538 1539static int 1540lastlog_perform_login(struct logininfo *li) 1541{ 1542 struct lastlog last; 1543 int fd; 1544 1545 /* create our struct lastlog */ 1546 lastlog_construct(li, &last); 1547 1548 if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT)) 1549 return (0); 1550 1551 /* write the entry */ 1552 if (atomicio(vwrite, fd, &last, sizeof(last)) != sizeof(last)) { 1553 close(fd); 1554 logit("%s: Error writing to %s: %s", __func__, 1555 LASTLOG_FILE, strerror(errno)); 1556 return (0); 1557 } 1558 1559 close(fd); 1560 return (1); 1561} 1562 1563int 1564lastlog_write_entry(struct logininfo *li) 1565{ 1566 switch(li->type) { 1567 case LTYPE_LOGIN: 1568 return (lastlog_perform_login(li)); 1569 default: 1570 logit("%s: Invalid type field", __func__); 1571 return (0); 1572 } 1573} 1574 1575static void 1576lastlog_populate_entry(struct logininfo *li, struct lastlog *last) 1577{ 1578 line_fullname(li->line, last->ll_line, sizeof(li->line)); 1579 strlcpy(li->hostname, last->ll_host, 1580 MIN_SIZEOF(li->hostname, last->ll_host)); 1581 li->tv_sec = last->ll_time; 1582} 1583 1584int 1585lastlog_get_entry(struct logininfo *li) 1586{ 1587 struct lastlog last; 1588 int fd, ret; 1589 1590 if (!lastlog_openseek(li, &fd, O_RDONLY)) 1591 return (0); 1592 1593 ret = atomicio(read, fd, &last, sizeof(last)); 1594 close(fd); 1595 1596 switch (ret) { 1597 case 0: 1598 memset(&last, '\0', sizeof(last)); 1599 /* FALLTHRU */ 1600 case sizeof(last): 1601 lastlog_populate_entry(li, &last); 1602 return (1); 1603 case -1: 1604 error("%s: Error reading from %s: %s", __func__, 1605 LASTLOG_FILE, strerror(errno)); 1606 return (0); 1607 default: 1608 error("%s: Error reading from %s: Expecting %d, got %d", 1609 __func__, LASTLOG_FILE, (int)sizeof(last), ret); 1610 return (0); 1611 } 1612 1613 /* NOTREACHED */ 1614 return (0); 1615} 1616#endif /* USE_LASTLOG */ 1617 1618#ifdef USE_BTMP 1619 /* 1620 * Logs failed login attempts in _PATH_BTMP if that exists. 1621 * The most common login failure is to give password instead of username. 1622 * So the _PATH_BTMP file checked for the correct permission, so that 1623 * only root can read it. 1624 */ 1625 1626void 1627record_failed_login(const char *username, const char *hostname, 1628 const char *ttyn) 1629{ 1630 int fd; 1631 struct utmp ut; 1632 struct sockaddr_storage from; 1633 socklen_t fromlen = sizeof(from); 1634 struct sockaddr_in *a4; 1635 struct sockaddr_in6 *a6; 1636 time_t t; 1637 struct stat fst; 1638 1639 if (geteuid() != 0) 1640 return; 1641 if ((fd = open(_PATH_BTMP, O_WRONLY | O_APPEND)) < 0) { 1642 debug("Unable to open the btmp file %s: %s", _PATH_BTMP, 1643 strerror(errno)); 1644 return; 1645 } 1646 if (fstat(fd, &fst) < 0) { 1647 logit("%s: fstat of %s failed: %s", __func__, _PATH_BTMP, 1648 strerror(errno)); 1649 goto out; 1650 } 1651 if((fst.st_mode & (S_IRWXG | S_IRWXO)) || (fst.st_uid != 0)){ 1652 logit("Excess permission or bad ownership on file %s", 1653 _PATH_BTMP); 1654 goto out; 1655 } 1656 1657 memset(&ut, 0, sizeof(ut)); 1658 /* strncpy because we don't necessarily want nul termination */ 1659 strncpy(ut.ut_user, username, sizeof(ut.ut_user)); 1660 strlcpy(ut.ut_line, "ssh:notty", sizeof(ut.ut_line)); 1661 1662 time(&t); 1663 ut.ut_time = t; /* ut_time is not always a time_t */ 1664 ut.ut_type = LOGIN_PROCESS; 1665 ut.ut_pid = getpid(); 1666 1667 /* strncpy because we don't necessarily want nul termination */ 1668 strncpy(ut.ut_host, hostname, sizeof(ut.ut_host)); 1669 1670 if (packet_connection_is_on_socket() && 1671 getpeername(packet_get_connection_in(), 1672 (struct sockaddr *)&from, &fromlen) == 0) { 1673 ipv64_normalise_mapped(&from, &fromlen); 1674 if (from.ss_family == AF_INET) { 1675 a4 = (struct sockaddr_in *)&from; 1676 memcpy(&ut.ut_addr, &(a4->sin_addr), 1677 MIN_SIZEOF(ut.ut_addr, a4->sin_addr)); 1678 } 1679#ifdef HAVE_ADDR_V6_IN_UTMP 1680 if (from.ss_family == AF_INET6) { 1681 a6 = (struct sockaddr_in6 *)&from; 1682 memcpy(&ut.ut_addr_v6, &(a6->sin6_addr), 1683 MIN_SIZEOF(ut.ut_addr_v6, a6->sin6_addr)); 1684 } 1685#endif 1686 } 1687 1688 if (atomicio(vwrite, fd, &ut, sizeof(ut)) != sizeof(ut)) 1689 error("Failed to write to %s: %s", _PATH_BTMP, 1690 strerror(errno)); 1691 1692out: 1693 close(fd); 1694} 1695#endif /* USE_BTMP */ 1696