1/* $NetBSD: mailwrapper.c,v 1.11 2018/01/23 21:06:25 sevan 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 40#define _PATH_MAILERCONF "/etc/mailer.conf" 41 42struct arglist { 43 size_t argc, maxc; 44 const char **argv; 45}; 46 47static void initarg(struct arglist *); 48static void addarg(struct arglist *, const char *, int); 49 50static void 51initarg(struct arglist *al) 52{ 53 al->argc = 0; 54 al->maxc = 10; 55 if ((al->argv = malloc(al->maxc * sizeof(char *))) == NULL) 56 /* 57 * This (using err("mailwrapper")) is intentional. 58 * Mailwrapper plays ugly games with argv[0] and thus it 59 * is often difficult for people to know that the error 60 * isn't from "mailq" or "sendmail" but from mailwrapper 61 * -- having mailwrapper add an indication that it was really 62 * mailwrapper running was a requested feature. 63 */ 64 err(1, "mailwrapper"); 65} 66 67static void 68addarg(struct arglist *al, const char *arg, int copy) 69{ 70 if (al->argc == al->maxc) { 71 al->maxc <<= 1; 72 if ((al->argv = realloc(al->argv, 73 al->maxc * sizeof(char *))) == NULL) 74 err(1, "mailwrapper"); 75 } 76 if (copy) { 77 if ((al->argv[al->argc++] = strdup(arg)) == NULL) 78 err(1, "mailwrapper:"); 79 } else 80 al->argv[al->argc++] = arg; 81} 82 83int 84main(int argc, char *argv[], char *envp[]) 85{ 86 FILE *config; 87 char *line, *cp, *from, *to, *ap; 88 size_t len, lineno = 0; 89 int i; 90 struct arglist al; 91 92 initarg(&al); 93 addarg(&al, argv[0], 0); 94 95 if ((config = fopen(_PATH_MAILERCONF, "r")) == NULL) 96 err(1, "mailwrapper: can't open %s", _PATH_MAILERCONF); 97 98 for (;;) { 99 if ((line = fparseln(config, &len, &lineno, NULL, 0)) == NULL) { 100 if (feof(config)) 101 errx(1, "mailwrapper: no mapping in %s", 102 _PATH_MAILERCONF); 103 err(1, "mailwrapper"); 104 } 105 106#define WS " \t\n" 107 cp = line; 108 109 cp += strspn(cp, WS); 110 if (cp[0] == '\0') { 111 /* empty line */ 112 free(line); 113 continue; 114 } 115 116 if ((from = strsep(&cp, WS)) == NULL) 117 goto parse_error; 118 119 cp += strspn(cp, WS); 120 121 if ((to = strsep(&cp, WS)) == NULL) 122 goto parse_error; 123 124 if (strcmp(from, getprogname()) == 0) { 125 for (ap = strsep(&cp, WS); ap != NULL; 126 ap = strsep(&cp, WS)) 127 if (*ap) 128 addarg(&al, ap, 0); 129 break; 130 } 131 132 free(line); 133 } 134 135 (void)fclose(config); 136 137 for (i = 1; i < argc; i++) 138 addarg(&al, argv[i], 0); 139 140 addarg(&al, NULL, 0); 141 execve(to, __UNCONST(al.argv), envp); 142 err(1, "mailwrapper: execing %s", to); 143 /*NOTREACHED*/ 144parse_error: 145 errx(1, "mailwrapper: parse error in %s at line %lu", 146 _PATH_MAILERCONF, (u_long)lineno); 147 /*NOTREACHED*/ 148} 149