1 /* $NetBSD: mailwrapper.c,v 1.3 1999/05/29 18:18:15 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1998 5 * Perry E. Metzger. 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 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgment: 17 * This product includes software developed for the NetBSD Project 18 * by Perry E. Metzger. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <err.h> 35 #include <stdio.h> 36 #include <string.h> 37 #include <stdlib.h> 38 #include <unistd.h> 39 #include <util.h> 40 41 #define _PATH_MAILERCONF "/etc/mailer.conf" 42 43 struct arglist { 44 size_t argc, maxc; 45 char **argv; 46 }; 47 48 int main __P((int, char *[], char *[])); 49 50 static void initarg __P((struct arglist *)); 51 static void addarg __P((struct arglist *, const char *, int)); 52 static void freearg __P((struct arglist *, int)); 53 54 extern const char *__progname; /* from crt0.o */ 55 56 static void 57 initarg(al) 58 struct arglist *al; 59 { 60 al->argc = 0; 61 al->maxc = 10; 62 if ((al->argv = malloc(al->maxc * sizeof(char *))) == NULL) 63 err(1, "mailwrapper"); 64 } 65 66 static void 67 addarg(al, arg, copy) 68 struct arglist *al; 69 const char *arg; 70 int copy; 71 { 72 if (al->argc == al->maxc) { 73 al->maxc <<= 1; 74 if ((al->argv = realloc(al->argv, 75 al->maxc * sizeof(char *))) == NULL) 76 err(1, "mailwrapper"); 77 } 78 if (copy) { 79 if ((al->argv[al->argc++] = strdup(arg)) == NULL) 80 err(1, "mailwrapper:"); 81 } else 82 al->argv[al->argc++] = (char *)arg; 83 } 84 85 static void 86 freearg(al, copy) 87 struct arglist *al; 88 int copy; 89 { 90 size_t i; 91 if (copy) 92 for (i = 0; i < al->argc; i++) 93 free(al->argv[i]); 94 free(al->argv); 95 } 96 97 int 98 main(argc, argv, envp) 99 int argc; 100 char *argv[]; 101 char *envp[]; 102 { 103 FILE *config; 104 char *line, *cp, *from, *to, *ap; 105 size_t len, lineno = 0; 106 struct arglist al; 107 108 initarg(&al); 109 for (len = 0; len < argc; len++) 110 addarg(&al, argv[len], 0); 111 112 if ((config = fopen(_PATH_MAILERCONF, "r")) == NULL) 113 err(1, "mailwrapper: can't open %s", _PATH_MAILERCONF); 114 115 for (;;) { 116 if ((line = fparseln(config, &len, &lineno, NULL, 0)) == NULL) { 117 if (feof(config)) 118 errx(1, "mailwrapper: no mapping in %s", 119 _PATH_MAILERCONF); 120 err(1, "mailwrapper"); 121 } 122 123 #define WS " \t\n" 124 cp = line; 125 126 cp += strspn(cp, WS); 127 if (cp[0] == '\0') { 128 /* empty line */ 129 free(line); 130 continue; 131 } 132 133 if ((from = strsep(&cp, WS)) == NULL) 134 goto parse_error; 135 136 cp += strspn(cp, WS); 137 138 if ((to = strsep(&cp, WS)) == NULL) 139 goto parse_error; 140 141 if (strcmp(from, __progname) == 0) { 142 for (ap = strsep(&cp, WS); ap != NULL; 143 ap = strsep(&cp, WS)) 144 if (*ap) 145 addarg(&al, ap, 0); 146 break; 147 } 148 149 free(line); 150 } 151 152 (void)fclose(config); 153 154 execve(to, al.argv, envp); 155 freearg(&al, 0); 156 free(line); 157 err(1, "mailwrapper: execing %s", to); 158 /*NOTREACHED*/ 159 parse_error: 160 freearg(&al, 0); 161 free(line); 162 errx(1, "mailwrapper: parse error in %s at line %lu", 163 _PATH_MAILERCONF, (u_long)lineno); 164 /*NOTREACHED*/ 165 } 166