1 /*- 2 * Copyright (c) 2009 Ed Schouten <ed@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <pwd.h> 31 #include <unistd.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include <sysexits.h> 35 #include <ulog.h> 36 37 /* 38 * This setuid helper utility writes user login records to disk. 39 * Unprivileged processes are not capable of writing records to utmp, 40 * wtmp and lastlog, but we do want to allow this for pseudo-terminals. 41 * Because a file descriptor to a pseudo-terminal master device can only 42 * be obtained by processes using the pseudo-terminal, we expect such a 43 * descriptor on stdin. 44 * 45 * It uses the real user ID of the calling process to determine the 46 * username. It does allow users to log arbitrary hostnames. 47 */ 48 49 int 50 main(int argc, char *argv[]) 51 { 52 const char *line; 53 54 /* Device line name. */ 55 if ((line = ptsname(STDIN_FILENO)) == NULL) 56 return (EX_USAGE); 57 58 if ((argc == 2 || argc == 3) && strcmp(argv[1], "login") == 0) { 59 struct passwd *pwd; 60 const char *host = NULL; 61 62 /* Username. */ 63 pwd = getpwuid(getuid()); 64 if (pwd == NULL) 65 return (EX_OSERR); 66 67 /* Hostname. */ 68 if (argc == 3) 69 host = argv[2]; 70 71 ulog_login(line, pwd->pw_name, host); 72 return (EX_OK); 73 } else if (argc == 2 && strcmp(argv[1], "logout") == 0) { 74 ulog_logout(line); 75 return (EX_OK); 76 } 77 78 return (EX_USAGE); 79 } 80