diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 14:40:04 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 14:40:04 +0000 |
commit | 25505898530a333011f4fd5cbc841ad6b26c089c (patch) | |
tree | 333a33fdd60930bcccc3f177ed9467d535e9bac6 /loginrec.c | |
parent | Initial commit. (diff) | |
download | openssh-upstream.tar.xz openssh-upstream.zip |
Adding upstream version 1:9.2p1.upstream/1%9.2p1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'loginrec.c')
-rw-r--r-- | loginrec.c | 1730 |
1 files changed, 1730 insertions, 0 deletions
diff --git a/loginrec.c b/loginrec.c new file mode 100644 index 0000000..4f21499 --- /dev/null +++ b/loginrec.c @@ -0,0 +1,1730 @@ +/* + * Copyright (c) 2000 Andre Lucas. All rights reserved. + * Portions copyright (c) 1998 Todd C. Miller + * Portions copyright (c) 1996 Jason Downs + * Portions copyright (c) 1996 Theo de Raadt + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/* + * The btmp logging code is derived from login.c from util-linux and is under + * the the following license: + * + * Copyright (c) 1980, 1987, 1988 The Regents of the University of California. + * All rights reserved. + * + * Redistribution and use in source and binary forms are permitted + * provided that the above copyright notice and this paragraph are + * duplicated in all such forms and that any documentation, + * advertising materials, and other materials related to such + * distribution and use acknowledge that the software was developed + * by the University of California, Berkeley. The name of the + * University may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + + +/** + ** loginrec.c: platform-independent login recording and lastlog retrieval + **/ + +/* + * The new login code explained + * ============================ + * + * This code attempts to provide a common interface to login recording + * (utmp and friends) and last login time retrieval. + * + * Its primary means of achieving this is to use 'struct logininfo', a + * union of all the useful fields in the various different types of + * system login record structures one finds on UNIX variants. + * + * We depend on autoconf to define which recording methods are to be + * used, and which fields are contained in the relevant data structures + * on the local system. Many C preprocessor symbols affect which code + * gets compiled here. + * + * The code is designed to make it easy to modify a particular + * recording method, without affecting other methods nor requiring so + * many nested conditional compilation blocks as were commonplace in + * the old code. + * + * For login recording, we try to use the local system's libraries as + * these are clearly most likely to work correctly. For utmp systems + * this usually means login() and logout() or setutent() etc., probably + * in libutil, along with logwtmp() etc. On these systems, we fall back + * to writing the files directly if we have to, though this method + * requires very thorough testing so we do not corrupt local auditing + * information. These files and their access methods are very system + * specific indeed. + * + * For utmpx systems, the corresponding library functions are + * setutxent() etc. To the author's knowledge, all utmpx systems have + * these library functions and so no direct write is attempted. If such + * a system exists and needs support, direct analogues of the [uw]tmp + * code should suffice. + * + * Retrieving the time of last login ('lastlog') is in some ways even + * more problemmatic than login recording. Some systems provide a + * simple table of all users which we seek based on uid and retrieve a + * relatively standard structure. Others record the same information in + * a directory with a separate file, and others don't record the + * information separately at all. For systems in the latter category, + * we look backwards in the wtmp or wtmpx file for the last login entry + * for our user. Naturally this is slower and on busy systems could + * incur a significant performance penalty. + * + * Calling the new code + * -------------------- + * + * In OpenSSH all login recording and retrieval is performed in + * login.c. Here you'll find working examples. Also, in the logintest.c + * program there are more examples. + * + * Internal handler calling method + * ------------------------------- + * + * When a call is made to login_login() or login_logout(), both + * routines set a struct logininfo flag defining which action (log in, + * or log out) is to be taken. They both then call login_write(), which + * calls whichever of the many structure-specific handlers autoconf + * selects for the local system. + * + * The handlers themselves handle system data structure specifics. Both + * struct utmp and struct utmpx have utility functions (see + * construct_utmp*()) to try to make it simpler to add extra systems + * that introduce new features to either structure. + * + * While it may seem terribly wasteful to replicate so much similar + * code for each method, experience has shown that maintaining code to + * write both struct utmp and utmpx in one function, whilst maintaining + * support for all systems whether they have library support or not, is + * a difficult and time-consuming task. + * + * Lastlog support proceeds similarly. Functions login_get_lastlog() + * (and its OpenSSH-tuned friend login_get_lastlog_time()) call + * getlast_entry(), which tries one of three methods to find the last + * login time. It uses local system lastlog support if it can, + * otherwise it tries wtmp or wtmpx before giving up and returning 0, + * meaning "tilt". + * + * Maintenance + * ----------- + * + * In many cases it's possible to tweak autoconf to select the correct + * methods for a particular platform, either by improving the detection + * code (best), or by presetting DISABLE_<method> or CONF_<method>_FILE + * symbols for the platform. + * + * Use logintest to check which symbols are defined before modifying + * configure.ac and loginrec.c. (You have to build logintest yourself + * with 'make logintest' as it's not built by default.) + * + * Otherwise, patches to the specific method(s) are very helpful! + */ + +#include "includes.h" + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/socket.h> +#ifdef HAVE_SYS_TIME_H +# include <sys/time.h> +#endif + +#include <netinet/in.h> + +#include <stdlib.h> +#include <errno.h> +#include <fcntl.h> +#ifdef HAVE_PATHS_H +# include <paths.h> +#endif +#include <pwd.h> +#include <stdarg.h> +#include <stdio.h> +#include <string.h> +#include <time.h> +#include <unistd.h> + +#include "xmalloc.h" +#include "sshkey.h" +#include "hostfile.h" +#include "ssh.h" +#include "loginrec.h" +#include "log.h" +#include "atomicio.h" +#include "packet.h" +#include "canohost.h" +#include "auth.h" +#include "sshbuf.h" +#include "ssherr.h" +#include "misc.h" + +#ifdef HAVE_UTIL_H +# include <util.h> +#endif + +/** + ** prototypes for helper functions in this file + **/ + +#if HAVE_UTMP_H +void set_utmp_time(struct logininfo *li, struct utmp *ut); +void construct_utmp(struct logininfo *li, struct utmp *ut); +#endif + +#ifdef HAVE_UTMPX_H +void set_utmpx_time(struct logininfo *li, struct utmpx *ut); +void construct_utmpx(struct logininfo *li, struct utmpx *ut); +#endif + +int utmp_write_entry(struct logininfo *li); +int utmpx_write_entry(struct logininfo *li); +int wtmp_write_entry(struct logininfo *li); +int wtmpx_write_entry(struct logininfo *li); +int lastlog_write_entry(struct logininfo *li); +int syslogin_write_entry(struct logininfo *li); + +int getlast_entry(struct logininfo *li); +int lastlog_get_entry(struct logininfo *li); +int utmpx_get_entry(struct logininfo *li); +int wtmp_get_entry(struct logininfo *li); +int wtmpx_get_entry(struct logininfo *li); + +extern struct sshbuf *loginmsg; + +/* pick the shortest string */ +#define MIN_SIZEOF(s1,s2) (sizeof(s1) < sizeof(s2) ? sizeof(s1) : sizeof(s2)) + +/** + ** platform-independent login functions + **/ + +/* + * login_login(struct logininfo *) - Record a login + * + * Call with a pointer to a struct logininfo initialised with + * login_init_entry() or login_alloc_entry() + * + * Returns: + * >0 if successful + * 0 on failure (will use OpenSSH's logging facilities for diagnostics) + */ +int +login_login(struct logininfo *li) +{ + li->type = LTYPE_LOGIN; + return (login_write(li)); +} + + +/* + * login_logout(struct logininfo *) - Record a logout + * + * Call as with login_login() + * + * Returns: + * >0 if successful + * 0 on failure (will use OpenSSH's logging facilities for diagnostics) + */ +int +login_logout(struct logininfo *li) +{ + li->type = LTYPE_LOGOUT; + return (login_write(li)); +} + +/* + * login_get_lastlog_time(int) - Retrieve the last login time + * + * Retrieve the last login time for the given uid. Will try to use the + * system lastlog facilities if they are available, but will fall back + * to looking in wtmp/wtmpx if necessary + * + * Returns: + * 0 on failure, or if user has never logged in + * Time in seconds from the epoch if successful + * + * Useful preprocessor symbols: + * DISABLE_LASTLOG: If set, *never* even try to retrieve lastlog + * info + * USE_LASTLOG: If set, indicates the presence of system lastlog + * facilities. If this and DISABLE_LASTLOG are not set, + * try to retrieve lastlog information from wtmp/wtmpx. + */ +unsigned int +login_get_lastlog_time(const uid_t uid) +{ + struct logininfo li; + + if (login_get_lastlog(&li, uid)) + return (li.tv_sec); + else + return (0); +} + +/* + * login_get_lastlog(struct logininfo *, int) - Retrieve a lastlog entry + * + * Retrieve a logininfo structure populated (only partially) with + * information from the system lastlog data, or from wtmp/wtmpx if no + * system lastlog information exists. + * + * Note this routine must be given a pre-allocated logininfo. + * + * Returns: + * >0: A pointer to your struct logininfo if successful + * 0 on failure (will use OpenSSH's logging facilities for diagnostics) + */ +struct logininfo * +login_get_lastlog(struct logininfo *li, const uid_t uid) +{ + struct passwd *pw; + + memset(li, '\0', sizeof(*li)); + li->uid = uid; + + /* + * If we don't have a 'real' lastlog, we need the username to + * reliably search wtmp(x) for the last login (see + * wtmp_get_entry().) + */ + pw = getpwuid(uid); + if (pw == NULL) + fatal("%s: Cannot find account for uid %ld", __func__, + (long)uid); + + if (strlcpy(li->username, pw->pw_name, sizeof(li->username)) >= + sizeof(li->username)) { + error("%s: username too long (%lu > max %lu)", __func__, + (unsigned long)strlen(pw->pw_name), + (unsigned long)sizeof(li->username) - 1); + return NULL; + } + + if (getlast_entry(li)) + return (li); + else + return (NULL); +} + +/* + * login_alloc_entry(int, char*, char*, char*) - Allocate and initialise + * a logininfo structure + * + * This function creates a new struct logininfo, a data structure + * meant to carry the information required to portably record login info. + * + * Returns a pointer to a newly created struct logininfo. If memory + * allocation fails, the program halts. + */ +struct +logininfo *login_alloc_entry(pid_t pid, const char *username, + const char *hostname, const char *line) +{ + struct logininfo *newli; + + newli = xmalloc(sizeof(*newli)); + login_init_entry(newli, pid, username, hostname, line); + return (newli); +} + + +/* login_free_entry(struct logininfo *) - free struct memory */ +void +login_free_entry(struct logininfo *li) +{ + free(li); +} + + +/* login_init_entry(struct logininfo *, int, char*, char*, char*) + * - initialise a struct logininfo + * + * Populates a new struct logininfo, a data structure meant to carry + * the information required to portably record login info. + * + * Returns: 1 + */ +int +login_init_entry(struct logininfo *li, pid_t pid, const char *username, + const char *hostname, const char *line) +{ + struct passwd *pw; + + memset(li, 0, sizeof(*li)); + + li->pid = pid; + + /* set the line information */ + if (line) + line_fullname(li->line, line, sizeof(li->line)); + + if (username) { + strlcpy(li->username, username, sizeof(li->username)); + pw = getpwnam(li->username); + if (pw == NULL) { + fatal("%s: Cannot find user \"%s\"", __func__, + li->username); + } + li->uid = pw->pw_uid; + } + + if (hostname) + strlcpy(li->hostname, hostname, sizeof(li->hostname)); + + return (1); +} + +/* + * login_set_current_time(struct logininfo *) - set the current time + * + * Set the current time in a logininfo structure. This function is + * meant to eliminate the need to deal with system dependencies for + * time handling. + */ +void +login_set_current_time(struct logininfo *li) +{ + struct timeval tv; + + gettimeofday(&tv, NULL); + + li->tv_sec = tv.tv_sec; + li->tv_usec = tv.tv_usec; +} + +/* copy a sockaddr_* into our logininfo */ +void +login_set_addr(struct logininfo *li, const struct sockaddr *sa, + const unsigned int sa_size) +{ + unsigned int bufsize = sa_size; + + /* make sure we don't overrun our union */ + if (sizeof(li->hostaddr) < sa_size) + bufsize = sizeof(li->hostaddr); + + memcpy(&li->hostaddr.sa, sa, bufsize); +} + + +/** + ** login_write: Call low-level recording functions based on autoconf + ** results + **/ +int +login_write(struct logininfo *li) +{ +#ifndef HAVE_CYGWIN + if (geteuid() != 0) { + logit("Attempt to write login records by non-root user (aborting)"); + return (1); + } +#endif + + /* set the timestamp */ + login_set_current_time(li); +#ifdef USE_LOGIN + syslogin_write_entry(li); +#endif +#ifdef USE_LASTLOG + if (li->type == LTYPE_LOGIN) + lastlog_write_entry(li); +#endif +#ifdef USE_UTMP + utmp_write_entry(li); +#endif +#ifdef USE_WTMP + wtmp_write_entry(li); +#endif +#ifdef USE_UTMPX + utmpx_write_entry(li); +#endif +#ifdef USE_WTMPX + wtmpx_write_entry(li); +#endif +#ifdef CUSTOM_SYS_AUTH_RECORD_LOGIN + if (li->type == LTYPE_LOGIN && + !sys_auth_record_login(li->username,li->hostname,li->line, + loginmsg)) + logit("Writing login record failed for %s", li->username); +#endif +#ifdef SSH_AUDIT_EVENTS + if (li->type == LTYPE_LOGIN) + audit_session_open(li); + else if (li->type == LTYPE_LOGOUT) + audit_session_close(li); +#endif + return (0); +} + +#ifdef LOGIN_NEEDS_UTMPX +int +login_utmp_only(struct logininfo *li) +{ + li->type = LTYPE_LOGIN; + login_set_current_time(li); +# ifdef USE_UTMP + utmp_write_entry(li); +# endif +# ifdef USE_WTMP + wtmp_write_entry(li); +# endif +# ifdef USE_UTMPX + utmpx_write_entry(li); +# endif +# ifdef USE_WTMPX + wtmpx_write_entry(li); +# endif + return (0); +} +#endif + +/** + ** getlast_entry: Call low-level functions to retrieve the last login + ** time. + **/ + +/* take the uid in li and return the last login time */ +int +getlast_entry(struct logininfo *li) +{ +#ifdef USE_LASTLOG + return(lastlog_get_entry(li)); +#else /* !USE_LASTLOG */ +#if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \ + defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER) + return (utmpx_get_entry(li)); +#endif + +#if defined(DISABLE_LASTLOG) + /* On some systems we shouldn't even try to obtain last login + * time, e.g. AIX */ + return (0); +# elif defined(USE_WTMP) && \ + (defined(HAVE_TIME_IN_UTMP) || defined(HAVE_TV_IN_UTMP)) + /* retrieve last login time from utmp */ + return (wtmp_get_entry(li)); +# elif defined(USE_WTMPX) && \ + (defined(HAVE_TIME_IN_UTMPX) || defined(HAVE_TV_IN_UTMPX)) + /* If wtmp isn't available, try wtmpx */ + return (wtmpx_get_entry(li)); +# else + /* Give up: No means of retrieving last login time */ + return (0); +# endif /* DISABLE_LASTLOG */ +#endif /* USE_LASTLOG */ +} + + + +/* + * 'line' string utility functions + * + * These functions process the 'line' string into one of three forms: + * + * 1. The full filename (including '/dev') + * 2. The stripped name (excluding '/dev') + * 3. The abbreviated name (e.g. /dev/ttyp00 -> yp00 + * /dev/pts/1 -> ts/1 ) + * + * Form 3 is used on some systems to identify a .tmp.? entry when + * attempting to remove it. Typically both addition and removal is + * performed by one application - say, sshd - so as long as the choice + * uniquely identifies a terminal it's ok. + */ + + +/* + * line_fullname(): add the leading '/dev/' if it doesn't exist make + * sure dst has enough space, if not just copy src (ugh) + */ +char * +line_fullname(char *dst, const char *src, u_int dstsize) +{ + memset(dst, '\0', dstsize); + if ((strncmp(src, "/dev/", 5) == 0) || (dstsize < (strlen(src) + 5))) + strlcpy(dst, src, dstsize); + else { + strlcpy(dst, "/dev/", dstsize); + strlcat(dst, src, dstsize); + } + return (dst); +} + +/* line_stripname(): strip the leading '/dev' if it exists, return dst */ +char * +line_stripname(char *dst, const char *src, int dstsize) +{ + memset(dst, '\0', dstsize); + if (strncmp(src, "/dev/", 5) == 0) + strlcpy(dst, src + 5, dstsize); + else + strlcpy(dst, src, dstsize); + return (dst); +} + +/* + * line_abbrevname(): Return the abbreviated (usually four-character) + * form of the line (Just use the last <dstsize> characters of the + * full name.) + * + * NOTE: use strncpy because we do NOT necessarily want zero + * termination + */ +char * +line_abbrevname(char *dst, const char *src, int dstsize) +{ + size_t len; + + memset(dst, '\0', dstsize); + + /* Always skip prefix if present */ + if (strncmp(src, "/dev/", 5) == 0) + src += 5; + +#ifdef WITH_ABBREV_NO_TTY + if (strncmp(src, "tty", 3) == 0) + src += 3; +#endif + + len = strlen(src); + + if (len > 0) { + if (((int)len - dstsize) > 0) + src += ((int)len - dstsize); + + /* note: _don't_ change this to strlcpy */ + strncpy(dst, src, (size_t)dstsize); + } + + return (dst); +} + +/** + ** utmp utility functions + ** + ** These functions manipulate struct utmp, taking system differences + ** into account. + **/ + +#if defined(USE_UTMP) || defined (USE_WTMP) || defined (USE_LOGIN) + +/* build the utmp structure */ +void +set_utmp_time(struct logininfo *li, struct utmp *ut) +{ +# if defined(HAVE_TV_IN_UTMP) + ut->ut_tv.tv_sec = li->tv_sec; + ut->ut_tv.tv_usec = li->tv_usec; +# elif defined(HAVE_TIME_IN_UTMP) + ut->ut_time = li->tv_sec; +# endif +} + +void +construct_utmp(struct logininfo *li, + struct utmp *ut) +{ +# ifdef HAVE_ADDR_V6_IN_UTMP + struct sockaddr_in6 *sa6; +# endif + + memset(ut, '\0', sizeof(*ut)); + + /* First fill out fields used for both logins and logouts */ + +# ifdef HAVE_ID_IN_UTMP + line_abbrevname(ut->ut_id, li->line, sizeof(ut->ut_id)); +# endif + +# ifdef HAVE_TYPE_IN_UTMP + /* This is done here to keep utmp constants out of struct logininfo */ + switch (li->type) { + case LTYPE_LOGIN: + ut->ut_type = USER_PROCESS; + break; + case LTYPE_LOGOUT: + ut->ut_type = DEAD_PROCESS; + break; + } +# endif + set_utmp_time(li, ut); + + line_stripname(ut->ut_line, li->line, sizeof(ut->ut_line)); + +# ifdef HAVE_PID_IN_UTMP + ut->ut_pid = li->pid; +# endif + + /* If we're logging out, leave all other fields blank */ + if (li->type == LTYPE_LOGOUT) + return; + + /* + * These fields are only used when logging in, and are blank + * for logouts. + */ + + /* Use strncpy because we don't necessarily want null termination */ + strncpy(ut->ut_name, li->username, + MIN_SIZEOF(ut->ut_name, li->username)); +# ifdef HAVE_HOST_IN_UTMP + strncpy(ut->ut_host, li->hostname, + MIN_SIZEOF(ut->ut_host, li->hostname)); +# endif +# ifdef HAVE_ADDR_IN_UTMP + /* this is just a 32-bit IP address */ + if (li->hostaddr.sa.sa_family == AF_INET) + ut->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr; +# endif +# ifdef HAVE_ADDR_V6_IN_UTMP + /* this is just a 128-bit IPv6 address */ + if (li->hostaddr.sa.sa_family == AF_INET6) { + sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa); + memcpy(ut->ut_addr_v6, sa6->sin6_addr.s6_addr, 16); + if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) { + ut->ut_addr_v6[0] = ut->ut_addr_v6[3]; + ut->ut_addr_v6[1] = 0; + ut->ut_addr_v6[2] = 0; + ut->ut_addr_v6[3] = 0; + } + } +# endif +} +#endif /* USE_UTMP || USE_WTMP || USE_LOGIN */ + +/** + ** utmpx utility functions + ** + ** These functions manipulate struct utmpx, accounting for system + ** variations. + **/ + +#if defined(USE_UTMPX) || defined (USE_WTMPX) +/* build the utmpx structure */ +void +set_utmpx_time(struct logininfo *li, struct utmpx *utx) +{ +# if defined(HAVE_TV_IN_UTMPX) + utx->ut_tv.tv_sec = li->tv_sec; + utx->ut_tv.tv_usec = li->tv_usec; +# elif defined(HAVE_TIME_IN_UTMPX) + utx->ut_time = li->tv_sec; +# endif +} + +void +construct_utmpx(struct logininfo *li, struct utmpx *utx) +{ +# ifdef HAVE_ADDR_V6_IN_UTMP + struct sockaddr_in6 *sa6; +# endif + memset(utx, '\0', sizeof(*utx)); + +# ifdef HAVE_ID_IN_UTMPX + line_abbrevname(utx->ut_id, li->line, sizeof(utx->ut_id)); +# endif + + /* this is done here to keep utmp constants out of loginrec.h */ + switch (li->type) { + case LTYPE_LOGIN: + utx->ut_type = USER_PROCESS; + break; + case LTYPE_LOGOUT: + utx->ut_type = DEAD_PROCESS; + break; + } + line_stripname(utx->ut_line, li->line, sizeof(utx->ut_line)); + set_utmpx_time(li, utx); + utx->ut_pid = li->pid; + + /* strncpy(): Don't necessarily want null termination */ + strncpy(utx->ut_user, li->username, + MIN_SIZEOF(utx->ut_user, li->username)); + + if (li->type == LTYPE_LOGOUT) + return; + + /* + * These fields are only used when logging in, and are blank + * for logouts. + */ + +# ifdef HAVE_HOST_IN_UTMPX + strncpy(utx->ut_host, li->hostname, + MIN_SIZEOF(utx->ut_host, li->hostname)); +# endif +# ifdef HAVE_SS_IN_UTMPX + utx->ut_ss = li->hostaddr.sa_storage; +# endif +# ifdef HAVE_ADDR_IN_UTMPX + /* this is just a 32-bit IP address */ + if (li->hostaddr.sa.sa_family == AF_INET) + utx->ut_addr = li->hostaddr.sa_in.sin_addr.s_addr; +# endif +# ifdef HAVE_ADDR_V6_IN_UTMP + /* this is just a 128-bit IPv6 address */ + if (li->hostaddr.sa.sa_family == AF_INET6) { + sa6 = ((struct sockaddr_in6 *)&li->hostaddr.sa); + memcpy(utx->ut_addr_v6, sa6->sin6_addr.s6_addr, 16); + if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr)) { + utx->ut_addr_v6[0] = utx->ut_addr_v6[3]; + utx->ut_addr_v6[1] = 0; + utx->ut_addr_v6[2] = 0; + utx->ut_addr_v6[3] = 0; + } + } +# endif +# ifdef HAVE_SYSLEN_IN_UTMPX + /* ut_syslen is the length of the utx_host string */ + utx->ut_syslen = MINIMUM(strlen(li->hostname), sizeof(utx->ut_host)); +# endif +} +#endif /* USE_UTMPX || USE_WTMPX */ + +/** + ** Low-level utmp functions + **/ + +/* FIXME: (ATL) utmp_write_direct needs testing */ +#ifdef USE_UTMP + +/* if we can, use pututline() etc. */ +# if !defined(DISABLE_PUTUTLINE) && defined(HAVE_SETUTENT) && \ + defined(HAVE_PUTUTLINE) +# define UTMP_USE_LIBRARY +# endif + + +/* write a utmp entry with the system's help (pututline() and pals) */ +# ifdef UTMP_USE_LIBRARY +static int +utmp_write_library(struct logininfo *li, struct utmp *ut) +{ + setutent(); + pututline(ut); +# ifdef HAVE_ENDUTENT + endutent(); +# endif + return (1); +} +# else /* UTMP_USE_LIBRARY */ + +/* + * Write a utmp entry direct to the file + * This is a slightly modification of code in OpenBSD's login.c + */ +static int +utmp_write_direct(struct logininfo *li, struct utmp *ut) +{ + struct utmp old_ut; + register int fd; + int tty; + + /* FIXME: (ATL) ttyslot() needs local implementation */ + +#if defined(HAVE_GETTTYENT) + struct ttyent *ty; + + tty=0; + setttyent(); + while (NULL != (ty = getttyent())) { + tty++; + if (!strncmp(ty->ty_name, ut->ut_line, sizeof(ut->ut_line))) + break; + } + endttyent(); + + if (NULL == ty) { + logit("%s: tty not found", __func__); + return (0); + } +#else /* FIXME */ + + tty = ttyslot(); /* seems only to work for /dev/ttyp? style names */ + +#endif /* HAVE_GETTTYENT */ + + if (tty > 0 && (fd = open(UTMP_FILE, O_RDWR|O_CREAT, 0644)) >= 0) { + off_t pos, ret; + + pos = (off_t)tty * sizeof(struct utmp); + if ((ret = lseek(fd, pos, SEEK_SET)) == -1) { + logit("%s: lseek: %s", __func__, strerror(errno)); + close(fd); + return (0); + } + if (ret != pos) { + logit("%s: Couldn't seek to tty %d slot in %s", + __func__, tty, UTMP_FILE); + close(fd); + return (0); + } + /* + * Prevent luser from zero'ing out ut_host. + * If the new ut_line is empty but the old one is not + * and ut_line and ut_name match, preserve the old ut_line. + */ + if (atomicio(read, fd, &old_ut, sizeof(old_ut)) == sizeof(old_ut) && + (ut->ut_host[0] == '\0') && (old_ut.ut_host[0] != '\0') && + (strncmp(old_ut.ut_line, ut->ut_line, sizeof(ut->ut_line)) == 0) && + (strncmp(old_ut.ut_name, ut->ut_name, sizeof(ut->ut_name)) == 0)) + memcpy(ut->ut_host, old_ut.ut_host, sizeof(ut->ut_host)); + + if ((ret = lseek(fd, pos, SEEK_SET)) == -1) { + logit("%s: lseek: %s", __func__, strerror(errno)); + close(fd); + return (0); + } + if (ret != pos) { + logit("%s: Couldn't seek to tty %d slot in %s", + __func__, tty, UTMP_FILE); + close(fd); + return (0); + } + if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) { + logit("%s: error writing %s: %s", __func__, + UTMP_FILE, strerror(errno)); + close(fd); + return (0); + } + + close(fd); + return (1); + } else { + return (0); + } +} +# endif /* UTMP_USE_LIBRARY */ + +static int +utmp_perform_login(struct logininfo *li) +{ + struct utmp ut; + + construct_utmp(li, &ut); +# ifdef UTMP_USE_LIBRARY + if (!utmp_write_library(li, &ut)) { + logit("%s: utmp_write_library() failed", __func__); + return (0); + } +# else + if (!utmp_write_direct(li, &ut)) { + logit("%s: utmp_write_direct() failed", __func__); + return (0); + } +# endif + return (1); +} + + +static int +utmp_perform_logout(struct logininfo *li) +{ + struct utmp ut; + + construct_utmp(li, &ut); +# ifdef UTMP_USE_LIBRARY + if (!utmp_write_library(li, &ut)) { + logit("%s: utmp_write_library() failed", __func__); + return (0); + } +# else + if (!utmp_write_direct(li, &ut)) { + logit("%s: utmp_write_direct() failed", __func__); + return (0); + } +# endif + return (1); +} + + +int +utmp_write_entry(struct logininfo *li) +{ + switch(li->type) { + case LTYPE_LOGIN: + return (utmp_perform_login(li)); + + case LTYPE_LOGOUT: + return (utmp_perform_logout(li)); + + default: + logit("%s: invalid type field", __func__); + return (0); + } +} +#endif /* USE_UTMP */ + + +/** + ** Low-level utmpx functions + **/ + +/* not much point if we don't want utmpx entries */ +#ifdef USE_UTMPX + +/* if we have the wherewithall, use pututxline etc. */ +# if !defined(DISABLE_PUTUTXLINE) && defined(HAVE_SETUTXENT) && \ + defined(HAVE_PUTUTXLINE) +# define UTMPX_USE_LIBRARY +# endif + + +/* write a utmpx entry with the system's help (pututxline() and pals) */ +# ifdef UTMPX_USE_LIBRARY +static int +utmpx_write_library(struct logininfo *li, struct utmpx *utx) +{ + setutxent(); + pututxline(utx); + +# ifdef HAVE_ENDUTXENT + endutxent(); +# endif + return (1); +} + +# else /* UTMPX_USE_LIBRARY */ + +/* write a utmp entry direct to the file */ +static int +utmpx_write_direct(struct logininfo *li, struct utmpx *utx) +{ + logit("%s: not implemented!", __func__); + return (0); +} +# endif /* UTMPX_USE_LIBRARY */ + +static int +utmpx_perform_login(struct logininfo *li) +{ + struct utmpx utx; + + construct_utmpx(li, &utx); +# ifdef UTMPX_USE_LIBRARY + if (!utmpx_write_library(li, &utx)) { + logit("%s: utmp_write_library() failed", __func__); + return (0); + } +# else + if (!utmpx_write_direct(li, &ut)) { + logit("%s: utmp_write_direct() failed", __func__); + return (0); + } +# endif + return (1); +} + + +static int +utmpx_perform_logout(struct logininfo *li) +{ + struct utmpx utx; + + construct_utmpx(li, &utx); +# ifdef HAVE_ID_IN_UTMPX + line_abbrevname(utx.ut_id, li->line, sizeof(utx.ut_id)); +# endif +# ifdef HAVE_TYPE_IN_UTMPX + utx.ut_type = DEAD_PROCESS; +# endif + +# ifdef UTMPX_USE_LIBRARY + utmpx_write_library(li, &utx); +# else + utmpx_write_direct(li, &utx); +# endif + return (1); +} + +int +utmpx_write_entry(struct logininfo *li) +{ + switch(li->type) { + case LTYPE_LOGIN: + return (utmpx_perform_login(li)); + case LTYPE_LOGOUT: + return (utmpx_perform_logout(li)); + default: + logit("%s: invalid type field", __func__); + return (0); + } +} +#endif /* USE_UTMPX */ + + +/** + ** Low-level wtmp functions + **/ + +#ifdef USE_WTMP + +/* + * Write a wtmp entry direct to the end of the file + * This is a slight modification of code in OpenBSD's logwtmp.c + */ +static int +wtmp_write(struct logininfo *li, struct utmp *ut) +{ + struct stat buf; + int fd, ret = 1; + + if ((fd = open(WTMP_FILE, O_WRONLY|O_APPEND, 0)) < 0) { + logit("%s: problem writing %s: %s", __func__, + WTMP_FILE, strerror(errno)); + return (0); + } + if (fstat(fd, &buf) == 0) + if (atomicio(vwrite, fd, ut, sizeof(*ut)) != sizeof(*ut)) { + ftruncate(fd, buf.st_size); + logit("%s: problem writing %s: %s", __func__, + WTMP_FILE, strerror(errno)); + ret = 0; + } + close(fd); + return (ret); +} + +static int +wtmp_perform_login(struct logininfo *li) +{ + struct utmp ut; + + construct_utmp(li, &ut); + return (wtmp_write(li, &ut)); +} + + +static int +wtmp_perform_logout(struct logininfo *li) +{ + struct utmp ut; + + construct_utmp(li, &ut); + return (wtmp_write(li, &ut)); +} + + +int +wtmp_write_entry(struct logininfo *li) +{ + switch(li->type) { + case LTYPE_LOGIN: + return (wtmp_perform_login(li)); + case LTYPE_LOGOUT: + return (wtmp_perform_logout(li)); + default: + logit("%s: invalid type field", __func__); + return (0); + } +} + + +/* + * Notes on fetching login data from wtmp/wtmpx + * + * Logouts are usually recorded with (amongst other things) a blank + * username on a given tty line. However, some systems (HP-UX is one) + * leave all fields set, but change the ut_type field to DEAD_PROCESS. + * + * Since we're only looking for logins here, we know that the username + * must be set correctly. On systems that leave it in, we check for + * ut_type==USER_PROCESS (indicating a login.) + * + * Portability: Some systems may set something other than USER_PROCESS + * to indicate a login process. I don't know of any as I write. Also, + * it's possible that some systems may both leave the username in + * place and not have ut_type. + */ + +/* return true if this wtmp entry indicates a login */ +static int +wtmp_islogin(struct logininfo *li, struct utmp *ut) +{ + if (strncmp(li->username, ut->ut_name, + MIN_SIZEOF(li->username, ut->ut_name)) == 0) { +# ifdef HAVE_TYPE_IN_UTMP + if (ut->ut_type & USER_PROCESS) + return (1); +# else + return (1); +# endif + } + return (0); +} + +int +wtmp_get_entry(struct logininfo *li) +{ + struct stat st; + struct utmp ut; + int fd, found = 0; + + /* Clear the time entries in our logininfo */ + li->tv_sec = li->tv_usec = 0; + + if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) { + logit("%s: problem opening %s: %s", __func__, + WTMP_FILE, strerror(errno)); + return (0); + } + if (fstat(fd, &st) != 0) { + logit("%s: couldn't stat %s: %s", __func__, + WTMP_FILE, strerror(errno)); + close(fd); + return (0); + } + + /* Seek to the start of the last struct utmp */ + if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) { + /* Looks like we've got a fresh wtmp file */ + close(fd); + return (0); + } + + while (!found) { + if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) { + logit("%s: read of %s failed: %s", __func__, + WTMP_FILE, strerror(errno)); + close (fd); + return (0); + } + if (wtmp_islogin(li, &ut) ) { + found = 1; + /* + * We've already checked for a time in struct + * utmp, in login_getlast() + */ +# ifdef HAVE_TIME_IN_UTMP + li->tv_sec = ut.ut_time; +# else +# if HAVE_TV_IN_UTMP + li->tv_sec = ut.ut_tv.tv_sec; +# endif +# endif + line_fullname(li->line, ut.ut_line, + MIN_SIZEOF(li->line, ut.ut_line)); +# ifdef HAVE_HOST_IN_UTMP + strlcpy(li->hostname, ut.ut_host, + MIN_SIZEOF(li->hostname, ut.ut_host)); +# endif + continue; + } + /* Seek back 2 x struct utmp */ + if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) { + /* We've found the start of the file, so quit */ + close(fd); + return (0); + } + } + + /* We found an entry. Tidy up and return */ + close(fd); + return (1); +} +# endif /* USE_WTMP */ + + +/** + ** Low-level wtmpx functions + **/ + +#ifdef USE_WTMPX +/* + * Write a wtmpx entry direct to the end of the file + * This is a slight modification of code in OpenBSD's logwtmp.c + */ +static int +wtmpx_write(struct logininfo *li, struct utmpx *utx) +{ +#ifndef HAVE_UPDWTMPX + struct stat buf; + int fd, ret = 1; + + if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) { + logit("%s: problem opening %s: %s", __func__, + WTMPX_FILE, strerror(errno)); + return (0); + } + + if (fstat(fd, &buf) == 0) + if (atomicio(vwrite, fd, utx, sizeof(*utx)) != sizeof(*utx)) { + ftruncate(fd, buf.st_size); + logit("%s: problem writing %s: %s", __func__, + WTMPX_FILE, strerror(errno)); + ret = 0; + } + close(fd); + + return (ret); +#else + updwtmpx(WTMPX_FILE, utx); + return (1); +#endif +} + + +static int +wtmpx_perform_login(struct logininfo *li) +{ + struct utmpx utx; + + construct_utmpx(li, &utx); + return (wtmpx_write(li, &utx)); +} + + +static int +wtmpx_perform_logout(struct logininfo *li) +{ + struct utmpx utx; + + construct_utmpx(li, &utx); + return (wtmpx_write(li, &utx)); +} + + +int +wtmpx_write_entry(struct logininfo *li) +{ + switch(li->type) { + case LTYPE_LOGIN: + return (wtmpx_perform_login(li)); + case LTYPE_LOGOUT: + return (wtmpx_perform_logout(li)); + default: + logit("%s: invalid type field", __func__); + return (0); + } +} + +/* Please see the notes above wtmp_islogin() for information about the + next two functions */ + +/* Return true if this wtmpx entry indicates a login */ +static int +wtmpx_islogin(struct logininfo *li, struct utmpx *utx) +{ + if (strncmp(li->username, utx->ut_user, + MIN_SIZEOF(li->username, utx->ut_user)) == 0 ) { +# ifdef HAVE_TYPE_IN_UTMPX + if (utx->ut_type == USER_PROCESS) + return (1); +# else + return (1); +# endif + } + return (0); +} + + +int +wtmpx_get_entry(struct logininfo *li) +{ + struct stat st; + struct utmpx utx; + int fd, found=0; + + /* Clear the time entries */ + li->tv_sec = li->tv_usec = 0; + + if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) { + logit("%s: problem opening %s: %s", __func__, + WTMPX_FILE, strerror(errno)); + return (0); + } + if (fstat(fd, &st) != 0) { + logit("%s: couldn't stat %s: %s", __func__, + WTMPX_FILE, strerror(errno)); + close(fd); + return (0); + } + + /* Seek to the start of the last struct utmpx */ + if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) { + /* probably a newly rotated wtmpx file */ + close(fd); + return (0); + } + + while (!found) { + if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) { + logit("%s: read of %s failed: %s", __func__, + WTMPX_FILE, strerror(errno)); + close (fd); + return (0); + } + /* + * Logouts are recorded as a blank username on a particular + * line. So, we just need to find the username in struct utmpx + */ + if (wtmpx_islogin(li, &utx)) { + found = 1; +# if defined(HAVE_TV_IN_UTMPX) + li->tv_sec = utx.ut_tv.tv_sec; +# elif defined(HAVE_TIME_IN_UTMPX) + li->tv_sec = utx.ut_time; +# endif + line_fullname(li->line, utx.ut_line, sizeof(li->line)); +# if defined(HAVE_HOST_IN_UTMPX) + strlcpy(li->hostname, utx.ut_host, + MIN_SIZEOF(li->hostname, utx.ut_host)); +# endif + continue; + } + if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) { + close(fd); + return (0); + } + } + + close(fd); + return (1); +} +#endif /* USE_WTMPX */ + +/** + ** Low-level libutil login() functions + **/ + +#ifdef USE_LOGIN +static int +syslogin_perform_login(struct logininfo *li) +{ + struct utmp *ut; + + ut = xmalloc(sizeof(*ut)); + construct_utmp(li, ut); + login(ut); + free(ut); + + return (1); +} + +static int +syslogin_perform_logout(struct logininfo *li) +{ +# ifdef HAVE_LOGOUT + char line[UT_LINESIZE]; + + (void)line_stripname(line, li->line, sizeof(line)); + + if (!logout(line)) + logit("%s: logout() returned an error", __func__); +# ifdef HAVE_LOGWTMP + else + logwtmp(line, "", ""); +# endif + /* FIXME: (ATL - if the need arises) What to do if we have + * login, but no logout? what if logout but no logwtmp? All + * routines are in libutil so they should all be there, + * but... */ +# endif + return (1); +} + +int +syslogin_write_entry(struct logininfo *li) +{ + switch (li->type) { + case LTYPE_LOGIN: + return (syslogin_perform_login(li)); + case LTYPE_LOGOUT: + return (syslogin_perform_logout(li)); + default: + logit("%s: Invalid type field", __func__); + return (0); + } +} +#endif /* USE_LOGIN */ + +/* end of file log-syslogin.c */ + +/** + ** Low-level lastlog functions + **/ + +#ifdef USE_LASTLOG + +#if !defined(LASTLOG_WRITE_PUTUTXLINE) || !defined(HAVE_GETLASTLOGXBYNAME) +/* open the file (using filemode) and seek to the login entry */ +static int +lastlog_openseek(struct logininfo *li, int *fd, int filemode) +{ + off_t offset; + char lastlog_file[1024]; + struct stat st; + + if (stat(LASTLOG_FILE, &st) != 0) { + logit("%s: Couldn't stat %s: %s", __func__, + LASTLOG_FILE, strerror(errno)); + return (0); + } + if (S_ISDIR(st.st_mode)) { + snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s", + LASTLOG_FILE, li->username); + } else if (S_ISREG(st.st_mode)) { + strlcpy(lastlog_file, LASTLOG_FILE, sizeof(lastlog_file)); + } else { + logit("%s: %.100s is not a file or directory!", __func__, + LASTLOG_FILE); + return (0); + } + + *fd = open(lastlog_file, filemode, 0600); + if (*fd < 0) { + debug("%s: Couldn't open %s: %s", __func__, + lastlog_file, strerror(errno)); + return (0); + } + + if (S_ISREG(st.st_mode)) { + /* find this uid's offset in the lastlog file */ + offset = (off_t) ((u_long)li->uid * sizeof(struct lastlog)); + + if (lseek(*fd, offset, SEEK_SET) != offset) { + logit("%s: %s->lseek(): %s", __func__, + lastlog_file, strerror(errno)); + close(*fd); + return (0); + } + } + + return (1); +} +#endif /* !LASTLOG_WRITE_PUTUTXLINE || !HAVE_GETLASTLOGXBYNAME */ + +#ifdef LASTLOG_WRITE_PUTUTXLINE +int +lastlog_write_entry(struct logininfo *li) +{ + switch(li->type) { + case LTYPE_LOGIN: + return 1; /* lastlog written by pututxline */ + default: + logit("lastlog_write_entry: Invalid type field"); + return 0; + } +} +#else /* LASTLOG_WRITE_PUTUTXLINE */ +int +lastlog_write_entry(struct logininfo *li) +{ + struct lastlog last; + int fd; + + switch(li->type) { + case LTYPE_LOGIN: + /* create our struct lastlog */ + memset(&last, '\0', sizeof(last)); + line_stripname(last.ll_line, li->line, sizeof(last.ll_line)); + strlcpy(last.ll_host, li->hostname, + MIN_SIZEOF(last.ll_host, li->hostname)); + last.ll_time = li->tv_sec; + + if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT)) + return (0); + + /* write the entry */ + if (atomicio(vwrite, fd, &last, sizeof(last)) != sizeof(last)) { + close(fd); + logit("%s: Error writing to %s: %s", __func__, + LASTLOG_FILE, strerror(errno)); + return (0); + } + + close(fd); + return (1); + default: + logit("%s: Invalid type field", __func__); + return (0); + } +} +#endif /* LASTLOG_WRITE_PUTUTXLINE */ + +#ifdef HAVE_GETLASTLOGXBYNAME +int +lastlog_get_entry(struct logininfo *li) +{ + struct lastlogx l, *ll; + + if ((ll = getlastlogxbyname(li->username, &l)) == NULL) { + memset(&l, '\0', sizeof(l)); + ll = &l; + } + line_fullname(li->line, ll->ll_line, sizeof(li->line)); + strlcpy(li->hostname, ll->ll_host, + MIN_SIZEOF(li->hostname, ll->ll_host)); + li->tv_sec = ll->ll_tv.tv_sec; + li->tv_usec = ll->ll_tv.tv_usec; + return (1); +} +#else /* HAVE_GETLASTLOGXBYNAME */ +int +lastlog_get_entry(struct logininfo *li) +{ + struct lastlog last; + int fd, ret; + + if (!lastlog_openseek(li, &fd, O_RDONLY)) + return (0); + + ret = atomicio(read, fd, &last, sizeof(last)); + close(fd); + + switch (ret) { + case 0: + memset(&last, '\0', sizeof(last)); + /* FALLTHRU */ + case sizeof(last): + line_fullname(li->line, last.ll_line, sizeof(li->line)); + strlcpy(li->hostname, last.ll_host, + MIN_SIZEOF(li->hostname, last.ll_host)); + li->tv_sec = last.ll_time; + return (1); + case -1: + error("%s: Error reading from %s: %s", __func__, + LASTLOG_FILE, strerror(errno)); + return (0); + default: + error("%s: Error reading from %s: Expecting %d, got %d", + __func__, LASTLOG_FILE, (int)sizeof(last), ret); + return (0); + } + + /* NOTREACHED */ + return (0); +} +#endif /* HAVE_GETLASTLOGXBYNAME */ +#endif /* USE_LASTLOG */ + +#if defined(USE_UTMPX) && defined(HAVE_SETUTXDB) && \ + defined(UTXDB_LASTLOGIN) && defined(HAVE_GETUTXUSER) +int +utmpx_get_entry(struct logininfo *li) +{ + struct utmpx *utx; + + if (setutxdb(UTXDB_LASTLOGIN, NULL) != 0) + return (0); + utx = getutxuser(li->username); + if (utx == NULL) { + endutxent(); + return (0); + } + + line_fullname(li->line, utx->ut_line, + MIN_SIZEOF(li->line, utx->ut_line)); + strlcpy(li->hostname, utx->ut_host, + MIN_SIZEOF(li->hostname, utx->ut_host)); + li->tv_sec = utx->ut_tv.tv_sec; + li->tv_usec = utx->ut_tv.tv_usec; + endutxent(); + return (1); +} +#endif /* USE_UTMPX && HAVE_SETUTXDB && UTXDB_LASTLOGIN && HAVE_GETUTXUSER */ + +#ifdef USE_BTMP + /* + * Logs failed login attempts in _PATH_BTMP if that exists. + * The most common login failure is to give password instead of username. + * So the _PATH_BTMP file checked for the correct permission, so that + * only root can read it. + */ + +void +record_failed_login(struct ssh *ssh, const char *username, const char *hostname, + const char *ttyn) +{ + int fd; + struct utmp ut; + struct sockaddr_storage from; + socklen_t fromlen = sizeof(from); + struct sockaddr_in *a4; + struct sockaddr_in6 *a6; + time_t t; + struct stat fst; + + if (geteuid() != 0) + return; + if ((fd = open(_PATH_BTMP, O_WRONLY | O_APPEND)) < 0) { + debug("Unable to open the btmp file %s: %s", _PATH_BTMP, + strerror(errno)); + return; + } + if (fstat(fd, &fst) < 0) { + logit("%s: fstat of %s failed: %s", __func__, _PATH_BTMP, + strerror(errno)); + goto out; + } + if((fst.st_mode & (S_IXGRP | S_IRWXO)) || (fst.st_uid != 0)){ + logit("Excess permission or bad ownership on file %s", + _PATH_BTMP); + goto out; + } + + memset(&ut, 0, sizeof(ut)); + /* strncpy because we don't necessarily want nul termination */ + strncpy(ut.ut_user, username, sizeof(ut.ut_user)); + strlcpy(ut.ut_line, "ssh:notty", sizeof(ut.ut_line)); + + time(&t); + ut.ut_time = t; /* ut_time is not always a time_t */ + ut.ut_type = LOGIN_PROCESS; + ut.ut_pid = getpid(); + + /* strncpy because we don't necessarily want nul termination */ + strncpy(ut.ut_host, hostname, sizeof(ut.ut_host)); + + if (ssh_packet_connection_is_on_socket(ssh) && + getpeername(ssh_packet_get_connection_in(ssh), + (struct sockaddr *)&from, &fromlen) == 0) { + ipv64_normalise_mapped(&from, &fromlen); + if (from.ss_family == AF_INET) { + a4 = (struct sockaddr_in *)&from; + memcpy(&ut.ut_addr, &(a4->sin_addr), + MIN_SIZEOF(ut.ut_addr, a4->sin_addr)); + } +#ifdef HAVE_ADDR_V6_IN_UTMP + if (from.ss_family == AF_INET6) { + a6 = (struct sockaddr_in6 *)&from; + memcpy(&ut.ut_addr_v6, &(a6->sin6_addr), + MIN_SIZEOF(ut.ut_addr_v6, a6->sin6_addr)); + } +#endif + } + + if (atomicio(vwrite, fd, &ut, sizeof(ut)) != sizeof(ut)) + error("Failed to write to %s: %s", _PATH_BTMP, + strerror(errno)); + +out: + close(fd); +} +#endif /* USE_BTMP */ |