1 /* $OpenBSD: mailwrapper.c,v 1.16 2004/07/06 03:38:14 millert Exp $ */ 2 /* $NetBSD: mailwrapper.c,v 1.9 2003/03/09 08:10:43 mjl Exp $ */ 3 4 /* 5 * Copyright (c) 1998 6 * Perry E. Metzger. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgment: 18 * This product includes software developed for the NetBSD Project 19 * by Perry E. Metzger. 20 * 4. The name of the author may not be used to endorse or promote products 21 * derived from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 26 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include <err.h> 39 #include <stdio.h> 40 #include <string.h> 41 #include <unistd.h> 42 #include <stdlib.h> 43 #include <libutil.h> 44 #include <sysexits.h> 45 #include <syslog.h> 46 47 #include "pathnames.h" 48 49 struct arglist { 50 size_t argc, maxc; 51 char **argv; 52 }; 53 54 int main(int, char *[], char *[]); 55 56 static void initarg(struct arglist *); 57 static void addarg(struct arglist *, const char *); 58 59 static void 60 initarg(struct arglist *al) 61 { 62 al->argc = 0; 63 al->maxc = 10; 64 if ((al->argv = malloc(al->maxc * sizeof(char *))) == NULL) 65 err(EX_TEMPFAIL, "malloc"); 66 } 67 68 static void 69 addarg(struct arglist *al, const char *arg) 70 { 71 72 if (al->argc == al->maxc) { 73 al->maxc <<= 1; 74 al->argv = realloc(al->argv, al->maxc * sizeof(char *)); 75 if (al->argv == NULL) 76 err(EX_TEMPFAIL, "realloc"); 77 } 78 if (arg == NULL) 79 al->argv[al->argc++] = NULL; 80 else if ((al->argv[al->argc++] = strdup(arg)) == NULL) 81 err(EX_TEMPFAIL, "strdup"); 82 } 83 84 int 85 main(int argc, char *argv[], char *envp[]) 86 { 87 FILE *config; 88 char *line, *cp, *from, *to, *ap; 89 const char *progname; 90 size_t len, lineno = 0; 91 int i; 92 struct arglist al; 93 94 /* change __progname to mailwrapper so we get sensible error messages */ 95 progname = getprogname(); 96 setprogname("mailwrapper"); 97 98 initarg(&al); 99 addarg(&al, argv[0]); 100 101 if ((config = fopen(_PATH_MAILERCONF, "r")) == NULL) { 102 addarg(&al, NULL); 103 openlog(getprogname(), LOG_PID, LOG_MAIL); 104 syslog(LOG_INFO, "cannot open %s, using %s as default MTA", 105 _PATH_MAILERCONF, _PATH_DEFAULTMTA); 106 closelog(); 107 execve(_PATH_DEFAULTMTA, al.argv, envp); 108 err(EX_OSERR, "cannot exec %s", _PATH_DEFAULTMTA); 109 /*NOTREACHED*/ 110 } 111 112 for (;;) { 113 if ((line = fparseln(config, &len, &lineno, NULL, 0)) == NULL) { 114 if (feof(config)) 115 errx(EX_CONFIG, "no mapping in %s", _PATH_MAILERCONF); 116 err(EX_CONFIG, "cannot parse line %lu", (u_long)lineno); 117 } 118 119 #define WS " \t\n" 120 cp = line; 121 122 cp += strspn(cp, WS); 123 if (cp[0] == '\0') { 124 /* empty line */ 125 free(line); 126 continue; 127 } 128 129 if ((from = strsep(&cp, WS)) == NULL) 130 goto parse_error; 131 132 cp += strspn(cp, WS); 133 134 if ((to = strsep(&cp, WS)) == NULL) 135 goto parse_error; 136 137 if (strcmp(from, progname) == 0) { 138 for (ap = strsep(&cp, WS); ap != NULL; 139 ap = strsep(&cp, WS)) { 140 if (*ap) 141 addarg(&al, ap); 142 } 143 break; 144 } 145 146 free(line); 147 } 148 149 (void)fclose(config); 150 151 for (i = 1; i < argc; i++) 152 addarg(&al, argv[i]); 153 154 addarg(&al, NULL); 155 execve(to, al.argv, envp); 156 err(EX_OSERR, "cannot exec %s", to); 157 /*NOTREACHED*/ 158 parse_error: 159 errx(EX_CONFIG, "parse error in %s at line %lu", 160 _PATH_MAILERCONF, (u_long)lineno); 161 /*NOTREACHED*/ 162 } 163