libexec/dma/net.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthias Schmidt <matthias@dragonflybsd.org>, University of Marburg,
   6  * Germany.
   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  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in
  16  *    the documentation and/or other materials provided with the
  17  *    distribution.
  18  * 3. Neither the name of The DragonFly Project nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific, prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * $DragonFly: src/libexec/dma/net.c,v 1.6 2008/04/20 13:44:24 swildner Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/queue.h>
  40 #include <sys/stat.h>
  41 #include <sys/types.h>
  42 #include <sys/socket.h>
  43 #include <netinet/in.h>
  44 #include <arpa/inet.h>
  45
  46 #ifdef HAVE_CRYPTO
  47 #include <openssl/ssl.h>
  48 #endif /* HAVE_CRYPTO */
  49
  50 #include <netdb.h>
  51 #include <setjmp.h>
  52 #include <signal.h>
  53 #include <syslog.h>
  54 #include <unistd.h>
  55
  56 #include "dma.h"
  57
  58 extern struct config *config;
  59 extern struct authusers authusers;
  60 static jmp_buf timeout_alarm;
  61
  62 static void
  63 sig_alarm(int signo __unused)
  64 {
  65         longjmp(timeout_alarm, 1);
  66 }
  67
  68 ssize_t
  69 send_remote_command(int fd, const char* fmt, ...)
  70 {
  71         va_list va;
  72         char cmd[4096];
  73         ssize_t len = 0;
  74
  75         va_start(va, fmt);
  76         vsprintf(cmd, fmt, va);
  77
  78         if (((config->features & SECURETRANS) != 0) &&
  79             ((config->features & NOSSL) == 0)) {
  80                 len = SSL_write(config->ssl, (const char*)cmd, strlen(cmd));
  81                 SSL_write(config->ssl, "\r\n", 2);
  82         }
  83         else {
  84                 len = write(fd, cmd, strlen(cmd));
  85                 write(fd, "\r\n", 2);
  86         }
  87         va_end(va);
  88
  89         return (len+2);
  90 }
  91
  92 int
  93 read_remote(int fd)
  94 {
  95         ssize_t rlen = 0;
  96         size_t pos, len;
  97         char buff[BUF_SIZE];
  98         int done = 0, status = 0;
  99
 100         if (signal(SIGALRM, sig_alarm) == SIG_ERR) {
 101                 syslog(LOG_ERR, "SIGALRM error: %m");
 102         }
 103         if (setjmp(timeout_alarm) != 0) {
 104                 syslog(LOG_ERR, "Timeout reached");
 105                 return (1);
 106         }
 107         alarm(CON_TIMEOUT);
 108
 109         /*
 110          * Remote reading code from femail.c written by Henning Brauer of
 111          * OpenBSD and released under a BSD style license.
 112          */
 113         for (len = pos = 0; !done; ) {
 114                 if (pos == 0 ||
 115                     (pos > 0 && memchr(buff + pos, '\n', len - pos) == NULL)) {
 116                         memmove(buff, buff + pos, len - pos);
 117                         len -= pos;
 118                         pos = 0;
 119                         if (((config->features & SECURETRANS) != 0) &&
 120                             (config->features & NOSSL) == 0) {
 121                                 if ((rlen = SSL_read(config->ssl, buff + len,
 122                                     sizeof(buff) - len)) == -1)
 123                                         err(1, "read");
 124                         } else {
 125                                 if ((rlen = read(fd, buff + len,
 126                                     sizeof(buff) - len)) == -1)
 127                                         err(1, "read");
 128                         }
 129                         len += rlen;
 130                 }
 131                 for (; pos < len && buff[pos] >= '0' && buff[pos] <= '9'; pos++)
 132                         ; /* Do nothing */
 133
 134                 if (pos == len)
 135                         return (0);
 136
 137                 if (buff[pos] == ' ')
 138                         done = 1;
 139                 else if (buff[pos] != '-')
 140                         syslog(LOG_ERR, "invalid syntax in reply from server");
 141
 142                 /* skip up to \n */
 143                 for (; pos < len && buff[pos - 1] != '\n'; pos++)
 144                         ; /* Do nothing */
 145
 146         }
 147         alarm(0);
 148
 149         status = atoi(buff);
 150         return (status/100);
 151 }
 152
 153 /*
 154  * Handle SMTP authentication
 155  *
 156  * XXX TODO: give me AUTH CRAM-MD5
 157  */
 158 static int
 159 smtp_login(struct qitem *it, int fd, char *login, char* password)
 160 {
 161         char *temp;
 162         int len, res = 0;
 163
 164         /* Send AUTH command according to RFC 2554 */
 165         send_remote_command(fd, "AUTH LOGIN");
 166         if (read_remote(fd) != 3) {
 167                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 168                        " AUTH login not available: %m", it->queueid);
 169                 return (1);
 170         }
 171
 172         len = base64_encode(login, strlen(login), &temp);
 173         if (len <= 0)
 174                 return (-1);
 175
 176         send_remote_command(fd, "%s", temp);
 177         if (read_remote(fd) != 3) {
 178                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 179                        " AUTH login failed: %m", it->queueid);
 180                 return (-1);
 181         }
 182
 183         len = base64_encode(password, strlen(password), &temp);
 184         if (len <= 0)
 185                 return (-1);
 186
 187         send_remote_command(fd, "%s", temp);
 188         res = read_remote(fd);
 189         if (res == 5) {
 190                 syslog(LOG_ERR, "%s: remote delivery failed:"
 191                        " Authentication failed: %m", it->queueid);
 192                 return (-1);
 193         } else if (res != 2) {
 194                 syslog(LOG_ERR, "%s: remote delivery failed:"
 195                        " AUTH password failed: %m", it->queueid);
 196                 return (-1);
 197         }
 198
 199         return (0);
 200 }
 201
 202 static int
 203 open_connection(struct qitem *it, const char *host)
 204 {
 205         struct addrinfo hints, *res, *res0;
 206         char servname[128];
 207         const char *errmsg = NULL;
 208         int fd, error = 0, port;
 209
 210         if (config->port != 0)
 211                 port = config->port;
 212         else
 213                 port = SMTP_PORT;
 214
 215         /* Shamelessly taken from getaddrinfo(3) */
 216         memset(&hints, 0, sizeof(hints));
 217         hints.ai_family = PF_UNSPEC;
 218         hints.ai_socktype = SOCK_STREAM;
 219         hints.ai_protocol = IPPROTO_TCP;
 220
 221         snprintf(servname, sizeof(servname), "%d", port);
 222         error = getaddrinfo(host, servname, &hints, &res0);
 223         if (error) {
 224                 syslog(LOG_ERR, "%s: remote delivery deferred: "
 225                        "%s: %m", it->queueid, gai_strerror(error));
 226                 return (-1);
 227         }
 228         fd = -1;
 229         for (res = res0; res; res = res->ai_next) {
 230                 fd=socket(res->ai_family, res->ai_socktype, res->ai_protocol);
 231                 if (fd < 0) {
 232                         errmsg = "socket failed";
 233                         continue;
 234                 }
 235                 if (connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
 236                         errmsg = "connect failed";
 237                         close(fd);
 238                         fd = -1;
 239                         continue;
 240                 }
 241                 break;
 242         }
 243         if (fd < 0) {
 244                 syslog(LOG_ERR, "%s: remote delivery deferred: %s (%s:%s)",
 245                         it->queueid, errmsg, host, servname);
 246                 freeaddrinfo(res0);
 247                 return (-1);
 248         }
 249         freeaddrinfo(res0);
 250         return (fd);
 251 }
 252
 253 int
 254 deliver_remote(struct qitem *it, const char **errmsg)
 255 {
 256         struct authuser *a;
 257         char *host, line[1000];
 258         int fd, error = 0, do_auth = 0, res = 0;
 259         size_t linelen;
 260
 261         host = strrchr(it->addr, '@');
 262         /* Should not happen */
 263         if (host == NULL)
 264                 return(-1);
 265         else
 266                 /* Step over the @ */
 267                 host++;
 268
 269         /* Smarthost support? */
 270         if (config->smarthost != NULL && strlen(config->smarthost) > 0) {
 271                 syslog(LOG_INFO, "%s: using smarthost (%s)",
 272                        it->queueid, config->smarthost);
 273                 host = config->smarthost;
 274         }
 275
 276         fd = open_connection(it, host);
 277         if (fd < 0)
 278                 return (1);
 279
 280         /* Check first reply from remote host */
 281         config->features |= NOSSL;
 282         res = read_remote(fd);
 283         if (res != 2) {
 284                 syslog(LOG_INFO, "%s: Invalid initial response: %i",
 285                         it->queueid, res);
 286                 return(1);
 287         }
 288         config->features &= ~NOSSL;
 289
 290 #ifdef HAVE_CRYPTO
 291         if ((config->features & SECURETRANS) != 0) {
 292                 error = smtp_init_crypto(it, fd, config->features);
 293                 if (error >= 0)
 294                         syslog(LOG_INFO, "%s: SSL initialization successful",
 295                                 it->queueid);
 296                 else
 297                         goto out;
 298         }
 299
 300         /*
 301          * If the user doesn't want STARTTLS, but SSL encryption, we
 302          * have to enable SSL first, then send EHLO
 303          */
 304         if (((config->features & STARTTLS) == 0) &&
 305             ((config->features & SECURETRANS) != 0)) {
 306                 send_remote_command(fd, "EHLO %s", hostname());
 307                 if (read_remote(fd) != 2) {
 308                         syslog(LOG_ERR, "%s: remote delivery deferred: "
 309                                " EHLO failed: %m", it->queueid);
 310                         return (-1);
 311                 }
 312         }
 313 #endif /* HAVE_CRYPTO */
 314         if (((config->features & SECURETRANS) == 0)) {
 315                 send_remote_command(fd, "EHLO %s", hostname());
 316                 if (read_remote(fd) != 2) {
 317                         syslog(LOG_ERR, "%s: remote delivery deferred: "
 318                                " EHLO failed: %m", it->queueid);
 319                         return (-1);
 320                 }
 321         }
 322
 323         /*
 324          * Use SMTP authentication if the user defined an entry for the remote
 325          * or smarthost
 326          */
 327         SLIST_FOREACH(a, &authusers, next) {
 328                 if (strcmp(a->host, host) == 0) {
 329                         do_auth = 1;
 330                         break;
 331                 }
 332         }
 333
 334         if (do_auth == 1) {
 335                 /*
 336                  * Check if the user wants plain text login without using
 337                  * encryption.
 338                  */
 339                 if ((config->features & INSECURE) != 0) {
 340                         syslog(LOG_INFO, "%s: Use SMTP authentication",
 341                                 it->queueid);
 342                         error = smtp_login(it, fd, a->login, a->password);
 343                         if (error < 0) {
 344                                 syslog(LOG_ERR, "%s: remote delivery failed:"
 345                                         " SMTP login failed: %m", it->queueid);
 346                                 return (-1);
 347                         }
 348                         /* SMTP login is not available, so try without */
 349                         else if (error > 0)
 350                                 syslog(LOG_ERR, "%s: SMTP login not available."
 351                                         " Try without", it->queueid);
 352                 } else {
 353                         syslog(LOG_ERR, "%s: Skip SMTP login. ",
 354                                 it->queueid);
 355                 }
 356         }
 357
 358         send_remote_command(fd, "MAIL FROM:<%s>", it->sender);
 359         if (read_remote(fd) != 2) {
 360                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 361                        " MAIL FROM failed: %m", it->queueid);
 362                 return (1);
 363         }
 364
 365         /* XXX TODO:
 366          * Iterate over all recepients and open only one connection
 367          */
 368         send_remote_command(fd, "RCPT TO:<%s>", it->addr);
 369         if (read_remote(fd) != 2) {
 370                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 371                        " RCPT TO failed: %m", it->queueid);
 372                 return (1);
 373         }
 374
 375         send_remote_command(fd, "DATA");
 376         if (read_remote(fd) != 3) {
 377                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 378                        " DATA failed: %m", it->queueid);
 379                 return (1);
 380         }
 381
 382         if (fseek(it->queuef, it->hdrlen, SEEK_SET) != 0) {
 383                 syslog(LOG_ERR, "%s: remote delivery deferred: cannot seek: %m",
 384                        it->queueid);
 385                 return (1);
 386         }
 387
 388         while (!feof(it->queuef)) {
 389                 if (fgets(line, sizeof(line), it->queuef) == NULL)
 390                         break;
 391                 linelen = strlen(line);
 392                 if (linelen == 0 || line[linelen - 1] != '\n') {
 393                         syslog(LOG_CRIT, "%s: remote delivery failed:"
 394                                 "corrupted queue file", it->queueid);
 395                         *errmsg = "corrupted queue file";
 396                         error = -1;
 397                         goto out;
 398                 }
 399
 400                 /* Remove trailing \n's and escape leading dots */
 401                 trim_line(line);
 402
 403                 /*
 404                  * If the first character is a dot, we escape it so the line
 405                  * length increases
 406                 */
 407                 if (line[0] == '.')
 408                         linelen++;
 409
 410                 if (send_remote_command(fd, "%s", line) != (ssize_t)linelen+1) {
 411                         syslog(LOG_ERR, "%s: remote delivery deferred: "
 412                                 "write error", it->queueid);
 413                         error = 1;
 414                         goto out;
 415                 }
 416         }
 417
 418         send_remote_command(fd, ".");
 419         if (read_remote(fd) != 2) {
 420                 syslog(LOG_ERR, "%s: remote delivery deferred: %m",
 421                        it->queueid);
 422                 return (1);
 423         }
 424
 425         send_remote_command(fd, "QUIT");
 426         if (read_remote(fd) != 2) {
 427                 syslog(LOG_ERR, "%s: remote delivery deferred: "
 428                        "QUIT failed: %m", it->queueid);
 429                 return (1);
 430         }
 431 out:
 432
 433         close(fd);
 434         return (error);
 435 }
 436