| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: qmail-checkspam.c,v 1.2 2004/04/08 01:36:26 mdw Exp $ |
| 4 | * |
| 5 | * Filter messages for spam |
| 6 | * |
| 7 | * (c) 2003 Mark Wooding |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License as published by |
| 14 | * the Free Software Foundation; either version 2 of the License, or |
| 15 | * (at your option) any later version. |
| 16 | * |
| 17 | * This program is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU General Public License |
| 23 | * along with this program; if not, write to the Free Software Foundation, |
| 24 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 25 | */ |
| 26 | |
| 27 | /*----- Header files ------------------------------------------------------*/ |
| 28 | |
| 29 | #include <ctype.h> |
| 30 | #include <errno.h> |
| 31 | #include <limits.h> |
| 32 | #include <stdio.h> |
| 33 | #include <stdlib.h> |
| 34 | #include <string.h> |
| 35 | |
| 36 | #include <sys/types.h> |
| 37 | #include <sys/unistd.h> |
| 38 | |
| 39 | #include <libspamc.h> |
| 40 | |
| 41 | /*----- Main code ---------------------------------------------------------*/ |
| 42 | |
| 43 | static const char *strenv(const char *e, const char *d) |
| 44 | { |
| 45 | const char *p = getenv(e); |
| 46 | if (!p) return (d); |
| 47 | return (p); |
| 48 | } |
| 49 | |
| 50 | static double dblenv(const char *e, double d) |
| 51 | { |
| 52 | const char *p = getenv(e); |
| 53 | char *q; |
| 54 | int err = errno; |
| 55 | double f; |
| 56 | if (!p) return (d); |
| 57 | errno = 0; |
| 58 | f = strtod(p, &q); |
| 59 | if (errno) return (d); |
| 60 | errno = err; |
| 61 | return (f); |
| 62 | } |
| 63 | |
| 64 | static int intenv(const char *e, int d) |
| 65 | { |
| 66 | const char *p = getenv(e); |
| 67 | char *q; |
| 68 | int err = errno; |
| 69 | long l; |
| 70 | if (!p) return (d); |
| 71 | errno = 0; |
| 72 | l = strtol(p, &q, 0); |
| 73 | if (errno) return (d); |
| 74 | errno = err; |
| 75 | if (l < 0 || l > INT_MAX) return (d); |
| 76 | return ((int)l); |
| 77 | } |
| 78 | |
| 79 | int shovel(int from, int to) |
| 80 | { |
| 81 | char buf[4096]; |
| 82 | ssize_t n; |
| 83 | char *p; |
| 84 | size_t r; |
| 85 | |
| 86 | for (;;) { |
| 87 | n = read(from, buf, sizeof(buf)); |
| 88 | if (n < 0 && errno != EINTR && errno != EAGAIN) |
| 89 | return (-1); |
| 90 | else if (!n) |
| 91 | return (0); |
| 92 | p = buf; |
| 93 | r = n; |
| 94 | while (r) { |
| 95 | n = write(to, p, n); |
| 96 | if (n <= 0 && errno != EINTR && errno != EAGAIN) |
| 97 | return (-1); |
| 98 | r -= n; |
| 99 | p += n; |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | int main(int argc, char *argv[]) |
| 105 | { |
| 106 | struct sockaddr sa; |
| 107 | struct message m; |
| 108 | int fd_m[2], fd_e[2]; |
| 109 | pid_t kid; |
| 110 | const char *qmq; |
| 111 | int rc; |
| 112 | |
| 113 | if (getenv("RELAYCLIENT")) goto exec; |
| 114 | m.max_len = intenv("QMAIL_CHECKSPAM_MAXLEN", 2 * 1024 * 1024); |
| 115 | m.timeout = intenv("QMAIL_CHECKSPAM_TIMEOUT", 300); |
| 116 | rc = message_read(0, 0, &m); |
| 117 | if (rc != 0 && rc != EX_TOOBIG) |
| 118 | return (54); |
| 119 | if (!rc) { |
| 120 | if (lookup_host(strenv("QMAIL_CHECKSPAM_SPAMDHOST", "localhost"), |
| 121 | intenv("QMAIL_CHECKSPAM_SPAMDPORT", 783), |
| 122 | &sa)) |
| 123 | return (56); |
| 124 | if (message_filter(&sa, "spamd", 0, &m)) |
| 125 | return (74); |
| 126 | if (m.score >= dblenv("QMAIL_CHECKSPAM_THRESH", m.threshold)) |
| 127 | return (31); |
| 128 | } |
| 129 | if (pipe(fd_m) || pipe(fd_e)) |
| 130 | return (56); |
| 131 | if ((kid = fork()) < 0) |
| 132 | return (56); |
| 133 | if (!kid) { |
| 134 | close(fd_m[0]); |
| 135 | close(fd_e[0]); |
| 136 | if (message_write(fd_m[1], &m) < 0) |
| 137 | _exit(127); |
| 138 | if (rc == EX_TOOBIG && shovel(0, fd_m[1])) |
| 139 | _exit(127); |
| 140 | close(fd_m[1]); |
| 141 | if (shovel(1, fd_e[1])) |
| 142 | _exit(127); |
| 143 | close(fd_e[1]); |
| 144 | _exit(0); |
| 145 | } |
| 146 | |
| 147 | dup2(fd_m[0], 0); |
| 148 | dup2(fd_e[0], 1); |
| 149 | close(fd_m[0]); |
| 150 | close(fd_e[0]); |
| 151 | close(fd_m[1]); |
| 152 | close(fd_e[1]); |
| 153 | exec: |
| 154 | qmq = strenv("QMAIL_CHECKSPAM_QUEUE", "/var/qmail/bin/qmail-queue"); |
| 155 | execlp(qmq, qmq, (char *)0); |
| 156 | fprintf(stderr, "failed to exec: %s\n", strerror(errno)); |
| 157 | return (56); |
| 158 | } |
| 159 | |
| 160 | /*----- That's all, folks -------------------------------------------------*/ |