1 /* $OpenBSD: mailwrapper.c,v 1.18 2007/11/06 14:39:19 otto Exp $ */ 2 /* $NetBSD: mailwrapper.c,v 1.9 2003/03/09 08:10:43 mjl Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-4-Clause 6 * 7 * Copyright (c) 1998 8 * Perry E. Metzger. All rights reserved. 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 acknowledgment: 20 * This product includes software developed for the NetBSD Project 21 * by Perry E. Metzger. 22 * 4. The name of the author may not be used to endorse or promote products 23 * derived from this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 42 #include <err.h> 43 #include <stdio.h> 44 #include <string.h> 45 #include <unistd.h> 46 #include <stdlib.h> 47 #include <libutil.h> 48 #include <sysexits.h> 49 #include <syslog.h> 50 51 #include "pathnames.h" 52 53 struct arglist { 54 size_t argc, maxc; 55 char **argv; 56 }; 57 58 int main(int, char *[], char *[]); 59 60 static void initarg(struct arglist *); 61 static void addarg(struct arglist *, const char *); 62 63 static void 64 initarg(struct arglist *al) 65 { 66 al->argc = 0; 67 al->maxc = 10; 68 if ((al->argv = calloc(al->maxc, sizeof(char *))) == NULL) 69 err(EX_TEMPFAIL, "calloc"); 70 } 71 72 static void 73 addarg(struct arglist *al, const char *arg) 74 { 75 76 if (al->argc == al->maxc) { 77 al->maxc <<= 1; 78 al->argv = realloc(al->argv, al->maxc * sizeof(char *)); 79 if (al->argv == NULL) 80 err(EX_TEMPFAIL, "realloc"); 81 } 82 if (arg == NULL) 83 al->argv[al->argc++] = NULL; 84 else if ((al->argv[al->argc++] = strdup(arg)) == NULL) 85 err(EX_TEMPFAIL, "strdup"); 86 } 87 88 int 89 main(int argc, char *argv[], char *envp[]) 90 { 91 FILE *config; 92 char *line, *cp, *from, *to, *ap; 93 const char *progname; 94 char localmailerconf[MAXPATHLEN]; 95 const char *mailerconf; 96 size_t len, lineno = 0; 97 int i; 98 struct arglist al; 99 100 /* change __progname to mailwrapper so we get sensible error messages */ 101 progname = getprogname(); 102 setprogname("mailwrapper"); 103 104 initarg(&al); 105 addarg(&al, argv[0]); 106 107 snprintf(localmailerconf, MAXPATHLEN, "%s/etc/mail/mailer.conf", 108 getenv("LOCALBASE") ? getenv("LOCALBASE") : "/usr/local"); 109 110 mailerconf = localmailerconf; 111 if ((config = fopen(localmailerconf, "r")) == NULL) 112 mailerconf = _PATH_MAILERCONF; 113 114 if (config == NULL && ((config = fopen(mailerconf, "r")) == NULL)) { 115 addarg(&al, NULL); 116 openlog(getprogname(), LOG_PID, LOG_MAIL); 117 syslog(LOG_INFO, "cannot open %s, using %s as default MTA", 118 mailerconf, _PATH_DEFAULTMTA); 119 closelog(); 120 execve(_PATH_DEFAULTMTA, al.argv, envp); 121 err(EX_OSERR, "cannot exec %s", _PATH_DEFAULTMTA); 122 /*NOTREACHED*/ 123 } 124 125 for (;;) { 126 if ((line = fparseln(config, &len, &lineno, NULL, 0)) == NULL) { 127 if (feof(config)) 128 errx(EX_CONFIG, "no mapping in %s", mailerconf); 129 err(EX_CONFIG, "cannot parse line %lu", (u_long)lineno); 130 } 131 132 #define WS " \t\n" 133 cp = line; 134 135 cp += strspn(cp, WS); 136 if (cp[0] == '\0') { 137 /* empty line */ 138 free(line); 139 continue; 140 } 141 142 if ((from = strsep(&cp, WS)) == NULL || cp == NULL) 143 goto parse_error; 144 145 cp += strspn(cp, WS); 146 147 if ((to = strsep(&cp, WS)) == NULL) 148 goto parse_error; 149 150 if (strcmp(from, progname) == 0) { 151 for (ap = strsep(&cp, WS); ap != NULL; 152 ap = strsep(&cp, WS)) { 153 if (*ap) 154 addarg(&al, ap); 155 } 156 break; 157 } 158 159 free(line); 160 } 161 162 (void)fclose(config); 163 164 for (i = 1; i < argc; i++) 165 addarg(&al, argv[i]); 166 167 addarg(&al, NULL); 168 execve(to, al.argv, envp); 169 err(EX_OSERR, "cannot exec %s", to); 170 /*NOTREACHED*/ 171 parse_error: 172 errx(EX_CONFIG, "parse error in %s at line %lu", 173 mailerconf, (u_long)lineno); 174 /*NOTREACHED*/ 175 } 176