/* * * login.c * * Author: Tatu Ylonen * * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved * * Created: Fri Mar 24 14:51:08 1995 ylo * * This file performs some of the things login(1) normally does. We cannot * easily use something like login -p -h host -f user, because there are * several different logins around, and it is hard to determined what kind of * login the current system has. Also, we want to be able to execute commands * on a tty. * */ #include "includes.h" RCSID("$Id: login.c,v 1.14 1999/12/27 23:41:12 damien Exp $"); #if defined(HAVE_UTMPX_H) && defined(USE_UTMPX) # include #endif #ifdef HAVE_UTMP_H # include #endif #include "ssh.h" #ifdef HAVE_UTIL_H # include #endif #ifdef HAVE_LASTLOG_H # include #endif #ifdef HAVE_LOGIN_H # include #endif /* * Returns the time when the user last logged in. Returns 0 if the * information is not available. This must be called before record_login. * The host the user logged in from will be returned in buf. */ /* * Returns the time when the user last logged in (or 0 if no previous login * is found). The name of the host used last time is returned in buf. */ unsigned long get_last_login_time(uid_t uid, const char *logname, char *buf, unsigned int bufsize) { #if defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) struct lastlog ll; char *lastlog; int fd; lastlog = _PATH_LASTLOG; buf[0] = '\0'; fd = open(lastlog, O_RDONLY); if (fd < 0) return 0; lseek(fd, (off_t) ((long) uid * sizeof(ll)), SEEK_SET); if (read(fd, &ll, sizeof(ll)) != sizeof(ll)) { close(fd); return 0; } close(fd); if (bufsize > sizeof(ll.ll_host) + 1) bufsize = sizeof(ll.ll_host) + 1; strncpy(buf, ll.ll_host, bufsize - 1); buf[bufsize - 1] = 0; return ll.ll_time; #else /* defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) */ /* Look in wtmp for the last login */ struct utmp wt; char *wt_file = _PATH_WTMP; int fd1; unsigned long t = 0; if ( (fd1 = open(wt_file, O_RDONLY)) < 0 ) { error("Couldn't open %.100s to find last login time.", wt_file); return 0; } /* seek to last record of file */ lseek(fd1, (off_t)(0-sizeof(struct utmp)), SEEK_END); /* loop through wtmp for our last user login record */ do { if (read(fd1, &wt, sizeof(wt)) != sizeof(wt)) { close(fd1); return 0; } if ( wt.ut_type == USER_PROCESS) { if ( !strncmp(logname, wt.ut_user, 8) ) { t = (unsigned long) wt.ut_time; #ifdef HAVE_HOST_IN_UTMP if (bufsize > sizeof(wt.ut_host) + 1) bufsize = sizeof(wt.ut_host) + 1; strncpy(buf, wt.ut_host, bufsize - 1); buf[bufsize - 1] = 0; #else /* HAVE_HOST_IN_UTMP */ buf[0] = 0; #endif /* HAVE_HOST_IN_UTMP */ } } if (lseek(fd1, (off_t)(0-2*sizeof(struct utmp)), SEEK_CUR) == -1) break; } while (t == 0); return t; #endif /* defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) */ } /* * Records that the user has logged in. I these parts of operating systems * were more standardized. */ void record_login(int pid, const char *ttyname, const char *user, uid_t uid, const char *host, struct sockaddr_in * addr) { #if defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) struct lastlog ll; char *lastlog; #endif /* defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) */ struct utmp u; #if defined(HAVE_UTMPX_H) && defined(USE_UTMPX) struct utmpx utx; #endif /* Construct an utmp/wtmp entry. */ memset(&u, 0, sizeof(u)); strncpy(u.ut_line, ttyname + 5, sizeof(u.ut_line)); strncpy(u.ut_id, ttyname + 8, sizeof(u.ut_id)); strncpy(u.ut_name, user, sizeof(u.ut_name)); #if defined(HAVE_TV_IN_UTMP) (void)gettimeofday(&u.ut_tv, NULL); #else /* defined(HAVE_TV_IN_UTMP) */ u.ut_time = time(NULL); #endif /* defined(HAVE_TV_IN_UTMP) */ #if defined(HAVE_PID_IN_UTMP) u.ut_pid = (pid_t)pid; #endif /* HAVE_PID_IN_UTMP */ #if defined(HAVE_TYPE_IN_UTMP) u.ut_type = (uid == -1)?DEAD_PROCESS:USER_PROCESS; #endif /* HAVE_TYPE_IN_UTMP */ #if defined(HAVE_HOST_IN_UTMP) strncpy(u.ut_host, host, sizeof(u.ut_host)); #endif #if defined(HAVE_UTMPX_H) && defined(USE_UTMPX) memset(&utx, 0, sizeof(utx)); strncpy(utx.ut_user, user, sizeof(utx.ut_name)); strncpy(utx.ut_line, ttyname + 5, sizeof(utx.ut_line)); strncpy(utx.ut_id, ttyname + 8, sizeof(utx.ut_id)); utx.ut_pid = (pid_t)pid; (void)gettimeofday(&utx.ut_tv, NULL); utx.ut_type = (uid == -1)?DEAD_PROCESS:USER_PROCESS; # ifdef HAVE_HOST_IN_UTMPX # ifdef HAVE_SYSLEN_IN_UTMPX utx.ut_syslen = strlen(host); strncpy(utx.ut_host, host, utx.ut_syslen); # else strncpy(utx.ut_host, host, sizeof(utx.ut_host)); # endif /* HAVE_SYSLEN_IN_UTMPX */ # endif #endif /* defined(HAVE_UTMPX_H) && defined(USE_UTMPX) */ /*#if defined(HAVE_UTMPX_H) && defined(USE_UTMPX) && !defined(HAVE_LOGIN)*/ #if defined(HAVE_UTMPX_H) && defined(USE_UTMPX) login(&u, &utx); #else /* defined(HAVE_UTMPX_H) && defined(USE_UTMPX) */ login(&u); #endif /* defined(HAVE_UTMPX_H) && defined(USE_UTMPX) */ #if defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) lastlog = _PATH_LASTLOG; /* Update lastlog unless actually recording a logout. */ if (strcmp(user, "") != 0) { int fd; /* * It is safer to bzero the lastlog structure first because * some systems might have some extra fields in it (e.g. SGI) */ memset(&ll, 0, sizeof(ll)); /* Update lastlog. */ ll.ll_time = time(NULL); strncpy(ll.ll_line, ttyname + 5, sizeof(ll.ll_line)); strncpy(ll.ll_host, host, sizeof(ll.ll_host)); fd = open(lastlog, O_RDWR); if (fd >= 0) { lseek(fd, (off_t) ((long) uid * sizeof(ll)), SEEK_SET); if (write(fd, &ll, sizeof(ll)) != sizeof(ll)) log("Could not write %.100s: %.100s", lastlog, strerror(errno)); close(fd); } } #endif /* defined(_PATH_LASTLOG) && !defined(DISABLE_LASTLOG) */ } /* Records that the user has logged out. */ void record_logout(int pid, const char *ttyname) { #ifdef HAVE_LIBUTIL_LOGIN const char *line = ttyname + 5; /* /dev/ttyq8 -> ttyq8 */ if (logout(line)) logwtmp(line, "", ""); #else /* HAVE_LIBUTIL_LOGIN */ record_login(pid, ttyname, "", -1, "", NULL); #endif /* HAVE_LIBUTIL_LOGIN */ }