1 /* $OpenBSD: sshlogin.c,v 1.29 2014/07/15 15:54:14 millert Exp $ */ 2 /* 3 * Author: Tatu Ylonen <ylo@cs.hut.fi> 4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 5 * All rights reserved 6 * This file performs some of the things login(1) normally does. We cannot 7 * easily use something like login -p -h host -f user, because there are 8 * several different logins around, and it is hard to determined what kind of 9 * login the current system has. Also, we want to be able to execute commands 10 * on a tty. 11 * 12 * As far as I am concerned, the code I have written for this software 13 * can be used freely for any purpose. Any derived versions of this 14 * software must be clearly marked as such, and if the derived work is 15 * incompatible with the protocol description in the RFC file, it must be 16 * called by a name other than "ssh" or "Secure Shell". 17 * 18 * Copyright (c) 1999 Theo de Raadt. All rights reserved. 19 * Copyright (c) 1999 Markus Friedl. All rights reserved. 20 * 21 * Redistribution and use in source and binary forms, with or without 22 * modification, are permitted provided that the following conditions 23 * are met: 24 * 1. Redistributions of source code must retain the above copyright 25 * notice, this list of conditions and the following disclaimer. 26 * 2. Redistributions in binary form must reproduce the above copyright 27 * notice, this list of conditions and the following disclaimer in the 28 * documentation and/or other materials provided with the distribution. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 33 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 35 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 39 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 40 */ 41 42 #include "includes.h" 43 44 #include <sys/types.h> 45 #include <sys/param.h> 46 #include <sys/socket.h> 47 48 #include <netinet/in.h> 49 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <stdarg.h> 53 #include <stdio.h> 54 #include <string.h> 55 #include <time.h> 56 #include <unistd.h> 57 58 #include "loginrec.h" 59 #include "log.h" 60 #include "buffer.h" 61 #include "misc.h" 62 #include "servconf.h" 63 #include "sshlogin.h" 64 65 extern Buffer loginmsg; 66 extern ServerOptions options; 67 68 /* 69 * Returns the time when the user last logged in. Returns 0 if the 70 * information is not available. This must be called before record_login. 71 * The host the user logged in from will be returned in buf. 72 */ 73 time_t 74 get_last_login_time(uid_t uid, const char *logname, 75 char *buf, size_t bufsize) 76 { 77 struct logininfo li; 78 79 login_get_lastlog(&li, uid); 80 strlcpy(buf, li.hostname, bufsize); 81 return (time_t)li.tv_sec; 82 } 83 84 /* 85 * Generate and store last login message. This must be done before 86 * login_login() is called and lastlog is updated. 87 */ 88 static void 89 store_lastlog_message(const char *user, uid_t uid) 90 { 91 #ifndef NO_SSH_LASTLOG 92 char *time_string, hostname[MAXHOSTNAMELEN] = "", buf[512]; 93 time_t last_login_time; 94 95 if (!options.print_lastlog) 96 return; 97 98 # ifdef CUSTOM_SYS_AUTH_GET_LASTLOGIN_MSG 99 time_string = sys_auth_get_lastlogin_msg(user, uid); 100 if (time_string != NULL) { 101 buffer_append(&loginmsg, time_string, strlen(time_string)); 102 free(time_string); 103 } 104 # else 105 last_login_time = get_last_login_time(uid, user, hostname, 106 sizeof(hostname)); 107 108 if (last_login_time != 0) { 109 time_string = ctime(&last_login_time); 110 time_string[strcspn(time_string, "\n")] = '\0'; 111 if (strcmp(hostname, "") == 0) 112 snprintf(buf, sizeof(buf), "Last login: %s\r\n", 113 time_string); 114 else 115 snprintf(buf, sizeof(buf), "Last login: %s from %s\r\n", 116 time_string, hostname); 117 buffer_append(&loginmsg, buf, strlen(buf)); 118 } 119 # endif /* CUSTOM_SYS_AUTH_GET_LASTLOGIN_MSG */ 120 #endif /* NO_SSH_LASTLOG */ 121 } 122 123 /* 124 * Records that the user has logged in. I wish these parts of operating 125 * systems were more standardized. 126 */ 127 void 128 record_login(pid_t pid, const char *tty, const char *user, uid_t uid, 129 const char *host, struct sockaddr *addr, socklen_t addrlen) 130 { 131 struct logininfo *li; 132 133 /* save previous login details before writing new */ 134 store_lastlog_message(user, uid); 135 136 li = login_alloc_entry(pid, user, host, tty); 137 login_set_addr(li, addr, addrlen); 138 login_login(li); 139 login_free_entry(li); 140 } 141 142 #ifdef LOGIN_NEEDS_UTMPX 143 void 144 record_utmp_only(pid_t pid, const char *ttyname, const char *user, 145 const char *host, struct sockaddr *addr, socklen_t addrlen) 146 { 147 struct logininfo *li; 148 149 li = login_alloc_entry(pid, user, host, ttyname); 150 login_set_addr(li, addr, addrlen); 151 login_utmp_only(li); 152 login_free_entry(li); 153 } 154 #endif 155 156 /* Records that the user has logged out. */ 157 void 158 record_logout(pid_t pid, const char *tty, const char *user) 159 { 160 struct logininfo *li; 161 162 li = login_alloc_entry(pid, user, NULL, tty); 163 login_logout(li); 164 login_free_entry(li); 165 } 166