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 * 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 <compat.h> 36 #include <err.h> 37 #include <stdio.h> 38 #include <string.h> 39 #include <unistd.h> 40 #include <stdlib.h> 41 #include <sysexits.h> 42 #include <syslog.h> 43 #include <limits.h> 44 45 #include "pathnames.h" 46 47 struct arglist { 48 size_t argc, maxc; 49 char **argv; 50 }; 51 52 int main(int, char *[], char *[]); 53 54 static void initarg(struct arglist *); 55 static void addarg(struct arglist *, const char *); 56 57 static void 58 initarg(struct arglist *al) 59 { 60 al->argc = 0; 61 al->maxc = 10; 62 if ((al->argv = calloc(al->maxc, sizeof (char *))) == NULL) 63 err(EX_TEMPFAIL, "calloc"); 64 } 65 66 static void 67 addarg(struct arglist *al, const char *arg) 68 { 69 70 if (al->argc == al->maxc) { 71 al->maxc <<= 1; 72 al->argv = realloc(al->argv, al->maxc * sizeof (char *)); 73 if (al->argv == NULL) 74 err(EX_TEMPFAIL, "realloc"); 75 } 76 if (arg == NULL) 77 al->argv[al->argc++] = NULL; 78 else if ((al->argv[al->argc++] = strdup(arg)) == NULL) 79 err(EX_TEMPFAIL, "strdup"); 80 } 81 82 int 83 main(int argc, char *argv[], char *envp[]) 84 { 85 FILE *config; 86 char *line, *cp, *from, *to, *ap; 87 char progname[PATH_MAX+1]; 88 const char *name; 89 size_t len, lineno = 0; 90 int i; 91 struct arglist al; 92 93 /* change __progname to mailwrapper so we get sensible error messages */ 94 name = getprogname(); 95 if (name) { 96 strncpy(progname, name, sizeof (progname)); 97 } else { 98 err(EX_OSERR, "cannot get program name"); 99 } 100 setprogname("mailwrapper"); 101 102 initarg(&al); 103 addarg(&al, argv[0]); 104 105 if ((config = fopen(_PATH_MAILERCONF, "r")) == NULL) { 106 addarg(&al, NULL); 107 openlog(getprogname(), LOG_PID, LOG_MAIL); 108 syslog(LOG_INFO, "cannot open %s, using %s as default MTA", 109 _PATH_MAILERCONF, _PATH_DEFAULTMTA); 110 closelog(); 111 execve(_PATH_DEFAULTMTA, al.argv, envp); 112 err(EX_OSERR, "cannot exec %s", _PATH_DEFAULTMTA); 113 /*NOTREACHED*/ 114 } 115 116 for (;;) { 117 if ((line = fparseln(config, &len, &lineno, NULL, 0)) == NULL) { 118 if (feof(config)) 119 errx(EX_CONFIG, "no mapping for %s in %s", 120 progname, _PATH_MAILERCONF); 121 err(EX_CONFIG, "cannot parse line %lu", 122 (ulong_t)lineno); 123 } 124 125 #define WS " \t\n" 126 cp = line; 127 128 cp += strspn(cp, WS); 129 if (cp[0] == '\0') { 130 /* empty line */ 131 free(line); 132 continue; 133 } 134 135 if ((from = strsep(&cp, WS)) == NULL || cp == NULL) 136 goto parse_error; 137 138 cp += strspn(cp, WS); 139 140 if ((to = strsep(&cp, WS)) == NULL) 141 goto parse_error; 142 143 if (strcmp(from, progname) == 0) { 144 for (ap = strsep(&cp, WS); ap != NULL; 145 ap = strsep(&cp, WS)) { 146 if (*ap) 147 addarg(&al, ap); 148 } 149 break; 150 } 151 152 free(line); 153 } 154 155 (void) fclose(config); 156 157 for (i = 1; i < argc; i++) 158 addarg(&al, argv[i]); 159 160 addarg(&al, NULL); 161 execve(to, al.argv, envp); 162 err(EX_OSERR, "cannot exec %s", to); 163 /*NOTREACHED*/ 164 parse_error: 165 errx(EX_CONFIG, "parse error in %s at line %lu", 166 _PATH_MAILERCONF, (ulong_t)lineno); 167 /*NOTREACHED*/ 168 return (0); 169 } 170