1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2009 Ed Schouten <ed@FreeBSD.org> 5 * All rights reserved. 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 AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #include <sys/wait.h> 31 32 #include <errno.h> 33 #include <signal.h> 34 #include <stdlib.h> 35 #include <sysexits.h> 36 #include <unistd.h> 37 #include "ulog.h" 38 39 #define _PATH_ULOG_HELPER "/usr/libexec/ulog-helper" 40 41 /* 42 * Registering login sessions. 43 */ 44 45 static void 46 ulog_exec_helper(int fd, char const * const argv[]) 47 { 48 sigset_t oblock, nblock; 49 pid_t pid, wpid; 50 int status; 51 52 /* Block SIGCHLD. */ 53 sigemptyset(&nblock); 54 sigaddset(&nblock, SIGCHLD); 55 sigprocmask(SIG_BLOCK, &nblock, &oblock); 56 57 switch (pid = fork()) { 58 case -1: 59 break; 60 case 0: 61 /* Execute helper program. */ 62 if (dup2(fd, STDIN_FILENO) == -1) 63 exit(EX_UNAVAILABLE); 64 sigprocmask(SIG_SETMASK, &oblock, NULL); 65 execv(_PATH_ULOG_HELPER, __DECONST(char * const *, argv)); 66 exit(EX_UNAVAILABLE); 67 default: 68 /* Wait for helper to finish. */ 69 do { 70 wpid = waitpid(pid, &status, 0); 71 } while (wpid == -1 && errno == EINTR); 72 break; 73 } 74 75 sigprocmask(SIG_SETMASK, &oblock, NULL); 76 } 77 78 void 79 ulog_login_pseudo(int fd, const char *host) 80 { 81 char const * const args[4] = { "ulog-helper", "login", host, NULL }; 82 83 ulog_exec_helper(fd, args); 84 } 85 86 void 87 ulog_logout_pseudo(int fd) 88 { 89 char const * const args[3] = { "ulog-helper", "logout", NULL }; 90 91 ulog_exec_helper(fd, args); 92 } 93