1 /* $NetBSD: ttyaction.c,v 1.16 2004/03/29 11:52:39 wiz Exp $ */ 2 3 /*- 4 * Copyright (c) 1996 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Gordon W. Ross. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * For each matching "tty" and "action" run the "command." 41 * See fnmatch() for matching the tty name. 42 */ 43 44 #include <sys/cdefs.h> 45 #if defined(LIBC_SCCS) && !defined(lint) 46 __RCSID("$NetBSD: ttyaction.c,v 1.16 2004/03/29 11:52:39 wiz Exp $"); 47 #endif /* LIBC_SCCS and not lint */ 48 49 #include <sys/types.h> 50 #include <sys/wait.h> 51 52 #include <assert.h> 53 #include <err.h> 54 #include <errno.h> 55 #include <fcntl.h> 56 #include <fnmatch.h> 57 #include <paths.h> 58 #include <stdio.h> 59 #include <stdlib.h> 60 #include <string.h> 61 #include <unistd.h> 62 63 #include "util.h" 64 65 #ifndef _PATH_TTYACTION 66 #define _PATH_TTYACTION "/etc/ttyaction" 67 #endif 68 69 static char *actfile = _PATH_TTYACTION; 70 static char *pathenv = "PATH=" _PATH_STDPATH; 71 72 int 73 ttyaction(const char *tty, const char *act, const char *user) 74 { 75 FILE *fp; 76 char *p1, *p2; 77 char *argv[4]; 78 char *envp[8]; 79 char *lastp; 80 char line[1024]; 81 char env_tty[64]; 82 char env_act[64]; 83 char env_user[256]; 84 int error, linenum, status; 85 pid_t pid; 86 87 _DIAGASSERT(tty != NULL); 88 _DIAGASSERT(act != NULL); 89 _DIAGASSERT(user != NULL); 90 91 fp = fopen(actfile, "r"); 92 if (fp == NULL) 93 return 0; 94 95 /* Skip the "/dev/" part of the first arg. */ 96 if (!strncmp(tty, "/dev/", 5)) 97 tty += 5; 98 99 /* Args will be: "sh -c ..." */ 100 argv[0] = _PATH_BSHELL; 101 argv[1] = "-c"; 102 argv[2] = NULL; /* see below */ 103 argv[3] = NULL; 104 105 /* 106 * Environment needs: TTY, ACT, USER 107 */ 108 snprintf(env_tty, sizeof(env_tty), "TTY=%s", tty); 109 snprintf(env_act, sizeof(env_act), "ACT=%s", act); 110 snprintf(env_user, sizeof(env_user), "USER=%s", user); 111 envp[0] = pathenv; 112 envp[1] = env_tty; 113 envp[2] = env_act; 114 envp[3] = env_user; 115 envp[4] = NULL; 116 117 linenum = 0; 118 status = 0; 119 while (fgets(line, sizeof(line), fp)) { 120 linenum++; 121 122 /* Allow comment lines. */ 123 if (line[0] == '#') 124 continue; 125 126 p1 = strtok_r(line, " \t", &lastp); 127 p2 = strtok_r(NULL, " \t", &lastp); 128 /* This arg goes to end of line. */ 129 argv[2] = strtok_r(NULL, "\n", &lastp); 130 if (!p1 || !p2 || !argv[2]) { 131 warnx("%s: line %d format error", actfile, linenum); 132 continue; 133 } 134 if (fnmatch(p1, tty, 0) || fnmatch(p2, act, 0)) 135 continue; 136 /* OK, this is a match. Run the command. */ 137 pid = fork(); 138 if (pid == -1) { 139 warnx("fork failed: %s", strerror(errno)); 140 continue; 141 } 142 if (pid == 0) { 143 /* This is the child. */ 144 error = execve(argv[0], argv, envp); 145 /* If we get here, it is an error. */ 146 warnx("%s: line %d: exec failed: %s", 147 actfile, linenum, strerror(errno)); 148 _exit(1); 149 } 150 /* This is the parent. */ 151 error = waitpid(pid, &status, 0); 152 if (error == -1) { 153 warnx("%s: line %d: wait failed: %s", 154 actfile, linenum, strerror(errno)); 155 continue; 156 } 157 if (WTERMSIG(status)) { 158 warnx("%s: line %d: child died with signal %d", 159 actfile, linenum, WTERMSIG(status)); 160 continue; 161 } 162 } 163 fclose(fp); 164 return status; 165 } 166