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 1.2 2008/02/03 11:06:17 matthias 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 & TLSINIT) == 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 static int
  93 read_remote_command(int fd, char *buff)
  94 {
  95         ssize_t len;
  96
  97         if (signal(SIGALRM, sig_alarm) == SIG_ERR) {
  98                 syslog(LOG_ERR, "SIGALRM error: %m");
  99         }
 100         if (setjmp(timeout_alarm) != 0) {
 101                 syslog(LOG_ERR, "Timeout reached");
 102                 return (1);
 103         }
 104         alarm(CON_TIMEOUT);
 105
 106         /*
 107          * According to RFC 821 a reply can consists of multiple lines, so
 108          * so read until the 4th char of the reply code is != '-'
 109          */
 110         if (((config->features & SECURETRANS) != 0) &&
 111             ((config->features & TLSINIT) == 0))
 112                 do {
 113                         len = SSL_read(config->ssl, buff, BUF_SIZE);
 114                 } while (len > 3 && buff[3] == '-');
 115         else
 116                 do {
 117                         len = read(fd, buff, BUF_SIZE);
 118                 } while (len > 3 && buff[3] == '-');
 119
 120         alarm(0);
 121
 122         return (0);
 123 }
 124
 125 int
 126 check_for_smtp_error(int fd, char *buff)
 127 {
 128         if (read_remote_command(fd, buff) < 0)
 129                 return (-1);
 130
 131         /* We received a 5XX reply thus an error happend */
 132         if (strncmp(buff, "5", 1) == 0) {
 133                 syslog(LOG_ERR, "SMTP error : %s", buff);
 134                 return (-1);
 135         }
 136         return (0);
 137 }
 138
 139 /*
 140  * Handle SMTP authentication
 141  *
 142  * XXX TODO: give me AUTH CRAM-MD5
 143  */
 144 static int
 145 smtp_login(struct qitem *it, int fd, char *login, char* password)
 146 {
 147         char buf[2048];
 148         char *temp;
 149         int len;
 150
 151         /* Send AUTH command according to RFC 2554 */
 152         send_remote_command(fd, "AUTH LOGIN");
 153         if (check_for_smtp_error(fd, buf) < 0) {
 154                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 155                        " AUTH login not available: %m", it->queueid);
 156                 return (1);
 157         }
 158
 159         len = base64_encode(login, strlen(login), &temp);
 160         if (len <= 0)
 161                 return (-1);
 162
 163         send_remote_command(fd, "%s", temp);
 164         if (check_for_smtp_error(fd, buf) < 0) {
 165                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 166                        " AUTH login failed: %m", it->queueid);
 167                 return (-1);
 168         }
 169
 170         len = base64_encode(password, strlen(password), &temp);
 171         if (len <= 0)
 172                 return (-1);
 173
 174         send_remote_command(fd, "%s", temp);
 175         if (check_for_smtp_error(fd, buf) < 0) {
 176                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 177                        " AUTH password failed: %m", it->queueid);
 178                 return (-1);
 179         }
 180
 181         return (0);
 182 }
 183
 184 static int
 185 open_connection(struct qitem *it, const char *host)
 186 {
 187 #ifdef HAVE_INET6
 188         struct addrinfo hints, *res, *res0;
 189         char servname[128];
 190         const char *errmsg = NULL;
 191 #else
 192         struct hostent *hn;
 193         struct sockaddr_in addr;
 194 #endif
 195         int fd, error = 0, port;
 196
 197         if (config->port != 0)
 198                 port = config->port;
 199         else
 200                 port = SMTP_PORT;
 201
 202 #ifdef HAVE_INET6
 203         /* Shamelessly taken from getaddrinfo(3) */
 204         memset(&hints, 0, sizeof(hints));
 205         hints.ai_family = PF_UNSPEC;
 206         hints.ai_socktype = SOCK_STREAM;
 207         hints.ai_protocol = IPPROTO_TCP;
 208
 209         snprintf(servname, sizeof(servname), "%d", port);
 210         error = getaddrinfo(host, servname, &hints, &res0);
 211         if (error) {
 212                 syslog(LOG_ERR, "%s: remote delivery deferred: "
 213                        "%s: %m", it->queueid, gai_strerror(error));
 214                 return (-1);
 215         }
 216         fd = -1;
 217         for (res = res0; res; res = res->ai_next) {
 218                 fd=socket(res->ai_family, res->ai_socktype, res->ai_protocol);
 219                 if (fd < 0) {
 220                         errmsg = "socket failed";
 221                         continue;
 222                 }
 223                 if (connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
 224                         errmsg = "connect failed";
 225                         close(fd);
 226                         fd = -1;
 227                         continue;
 228                 }
 229                 break;
 230         }
 231         if (fd < 0) {
 232                 syslog(LOG_ERR, "%s: remote delivery deferred: %s (%s:%s)",
 233                         it->queueid, errmsg, host, servname);
 234                 freeaddrinfo(res0);
 235                 return (-1);
 236         }
 237         freeaddrinfo(res0);
 238 #else
 239         memset(&addr, 0, sizeof(addr));
 240         fd = socket(AF_INET, SOCK_STREAM, 0);
 241         addr.sin_family = AF_INET;
 242
 243         addr.sin_port = htons(port);
 244         error = inet_pton(AF_INET, host, &addr.sin_addr);
 245         if (error < 0) {
 246                 syslog(LOG_ERR, "%s: remote delivery deferred: "
 247                         "address conversion failed: %m", it->queueid);
 248                 return (1);
 249         }
 250         hn = gethostbyname(host);
 251         if (hn == NULL) {
 252                 syslog(LOG_ERR, "%s: remote delivery deferred: cannot resolve "
 253                         "hostname (%s) %m", it->queueid, host);
 254                 return (-1);
 255         } else {
 256                 memcpy(&addr.sin_addr, hn->h_addr, sizeof(struct in_addr));
 257                 if (hn->h_length != 4)
 258                         return (-1);
 259         }
 260
 261         error = connect(fd, (struct sockaddr *) &addr, sizeof(addr));
 262         if (error < 0) {
 263                 syslog(LOG_ERR, "%s: remote delivery deferred: "
 264                        "connection failed : %m", it->queueid);
 265                 return (-1);
 266         }
 267 #endif
 268         return (fd);
 269 }
 270
 271 int
 272 deliver_remote(struct qitem *it, const char **errmsg)
 273 {
 274         struct authuser *a;
 275         char *host, buf[2048], line[1000];
 276         int fd, error = 0, do_auth = 0;
 277         size_t linelen;
 278
 279         host = strrchr(it->addr, '@');
 280         /* Should not happen */
 281         if (host == NULL)
 282                 return(-1);
 283         else
 284                 /* Step over the @ */
 285                 host++;
 286
 287         /* Smarthost support? */
 288         if (config->smarthost != NULL && strlen(config->smarthost) > 0) {
 289                 syslog(LOG_INFO, "%s: using smarthost (%s)",
 290                        it->queueid, config->smarthost);
 291                 host = config->smarthost;
 292         }
 293
 294         fd = open_connection(it, host);
 295         if (fd < 0)
 296                 return (1);
 297
 298 #ifdef HAVE_CRYPTO
 299         if ((config->features & SECURETRANS) != 0) {
 300                 error = smtp_init_crypto(it, fd, config->features);
 301                 if (error >= 0)
 302                         syslog(LOG_INFO, "%s: SSL initialization sucessful",
 303                                 it->queueid);
 304                 else
 305                         goto out;
 306         }
 307
 308         /*
 309          * If the user doesn't want STARTTLS, but SSL encryption, we
 310          * have to enable SSL first, then send EHLO
 311          */
 312         if (((config->features & STARTTLS) == 0) &&
 313             ((config->features & SECURETRANS) != 0)) {
 314                 send_remote_command(fd, "EHLO %s", hostname());
 315                 if (check_for_smtp_error(fd, buf) < 0) {
 316                         syslog(LOG_ERR, "%s: remote delivery deferred: "
 317                                " EHLO failed: %m", it->queueid);
 318                         return (-1);
 319                 }
 320         }
 321 #endif /* HAVE_CRYPTO */
 322         if (((config->features & SECURETRANS) == 0)) {
 323                 send_remote_command(fd, "EHLO %s", hostname());
 324                 if (check_for_smtp_error(fd, buf) < 0) {
 325                         syslog(LOG_ERR, "%s: remote delivery deferred: "
 326                                " EHLO failed: %m", it->queueid);
 327                         return (-1);
 328                 }
 329         }
 330
 331         /*
 332          * Use SMTP authentication if the user defined an entry for the remote
 333          * or smarthost
 334          */
 335         SLIST_FOREACH(a, &authusers, next) {
 336                 if (strcmp(a->host, host) == 0) {
 337                         do_auth = 1;
 338                         break;
 339                 }
 340         }
 341
 342         if (do_auth == 1) {
 343                 syslog(LOG_INFO, "%s: Use SMTP authentication", it->queueid);
 344                 error = smtp_login(it, fd, a->login, a->password);
 345                 if (error < 0) {
 346                         syslog(LOG_ERR, "%s: remote delivery failed:"
 347                                 " SMTP login failed: %m", it->queueid);
 348                         return (-1);
 349                 }
 350                 /* SMTP login is not available, so try without */
 351                 else if (error > 0)
 352                         syslog(LOG_ERR, "%s: SMTP login not available. Try without",
 353                                 it->queueid);
 354         }
 355
 356         send_remote_command(fd, "MAIL FROM:<%s>", it->sender);
 357         if (check_for_smtp_error(fd, buf) < 0) {
 358                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 359                        " MAIL FROM failed: %m", it->queueid);
 360                 return (1);
 361         }
 362
 363         /* XXX TODO:
 364          * Iterate over all recepients and open only one connection
 365          */
 366         send_remote_command(fd, "RCPT TO:<%s>", it->addr);
 367         if (check_for_smtp_error(fd, buf) < 0) {
 368                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 369                        " RCPT TO failed: %m", it->queueid);
 370                 return (1);
 371         }
 372
 373         send_remote_command(fd, "DATA");
 374         if (check_for_smtp_error(fd, buf) < 0) {
 375                 syslog(LOG_ERR, "%s: remote delivery deferred:"
 376                        " DATA failed: %m", it->queueid);
 377                 return (1);
 378         }
 379
 380         if (fseek(it->queuef, it->hdrlen, SEEK_SET) != 0) {
 381                 syslog(LOG_ERR, "%s: remote delivery deferred: cannot seek: %m",
 382                        it->queueid);
 383                 return (1);
 384         }
 385
 386         while (!feof(it->queuef)) {
 387                 if (fgets(line, sizeof(line), it->queuef) == NULL)
 388                         break;
 389                 linelen = strlen(line);
 390                 if (linelen == 0 || line[linelen - 1] != '\n') {
 391                         syslog(LOG_CRIT, "%s: remote delivery failed:"
 392                                 "corrupted queue file", it->queueid);
 393                         *errmsg = "corrupted queue file";
 394                         error = -1;
 395                         goto out;
 396                 }
 397
 398                 /* Remove trailing \n's and escape leading dots */
 399                 trim_line(line);
 400
 401                 /*
 402                  * If the first character is a dot, we escape it so the line
 403                  * length increases
 404                 */
 405                 if (line[0] == '.')
 406                         linelen++;
 407
 408                 if (send_remote_command(fd, "%s", line) != (ssize_t)linelen+1) {
 409                         syslog(LOG_ERR, "%s: remote delivery deferred: "
 410                                 "write error", it->queueid);
 411                         error = 1;
 412                         goto out;
 413                 }
 414         }
 415
 416         send_remote_command(fd, ".");
 417         if (check_for_smtp_error(fd, buf) < 0) {
 418                 syslog(LOG_ERR, "%s: remote delivery deferred: %m",
 419                        it->queueid);
 420                 return (1);
 421         }
 422
 423         send_remote_command(fd, "QUIT");
 424         if (check_for_smtp_error(fd, buf) < 0) {
 425                 syslog(LOG_ERR, "%s: remote delivery deferred: "
 426                        "QUIT failed: %m", it->queueid);
 427                 return (1);
 428         }
 429 out:
 430
 431         close(fd);
 432         return (error);
 433 }
 434