src/common/smtp.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2004 Hiroyuki Yamamoto
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #  include "config.h"
  22 #endif
  23
  24 #include <glib.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27
  28 #include "intl.h"
  29 #include "smtp.h"
  30 #include "md5.h"
  31 #include "base64.h"
  32 #include "utils.h"
  33 #include "log.h"
  34
  35 static void smtp_session_destroy(Session *session);
  36
  37 static gint smtp_from(SMTPSession *session);
  38
  39 static gint smtp_auth(SMTPSession *session);
  40 static gint smtp_starttls(SMTPSession *session);
  41 static gint smtp_auth_cram_md5(SMTPSession *session);
  42 static gint smtp_auth_login(SMTPSession *session);
  43
  44 static gint smtp_ehlo(SMTPSession *session);
  45 static gint smtp_ehlo_recv(SMTPSession *session, const gchar *msg);
  46
  47 static gint smtp_helo(SMTPSession *session);
  48 static gint smtp_rcpt(SMTPSession *session);
  49 static gint smtp_data(SMTPSession *session);
  50 static gint smtp_send_data(SMTPSession *session);
  51 /* static gint smtp_rset(SMTPSession *session); */
  52 static gint smtp_quit(SMTPSession *session);
  53 static gint smtp_eom(SMTPSession *session);
  54
  55 static gint smtp_session_recv_msg(Session *session, const gchar *msg);
  56 static gint smtp_session_send_data_finished(Session *session, guint len);
  57
  58
  59 Session *smtp_session_new(void)
  60 {
  61         SMTPSession *session;
  62
  63         session = g_new0(SMTPSession, 1);
  64
  65         session_init(SESSION(session));
  66
  67         SESSION(session)->type             = SESSION_SMTP;
  68
  69         SESSION(session)->recv_msg         = smtp_session_recv_msg;
  70
  71         SESSION(session)->recv_data_finished = NULL;
  72         SESSION(session)->send_data_finished = smtp_session_send_data_finished;
  73
  74         SESSION(session)->destroy          = smtp_session_destroy;
  75
  76         session->state                     = SMTP_READY;
  77
  78 #if USE_OPENSSL
  79         session->tls_init_done             = FALSE;
  80 #endif
  81
  82         session->hostname                  = NULL;
  83         session->user                      = NULL;
  84         session->pass                      = NULL;
  85
  86         session->from                      = NULL;
  87         session->to_list                   = NULL;
  88         session->cur_to                    = NULL;
  89
  90         session->send_data                 = NULL;
  91         session->send_data_len             = 0;
  92
  93         session->max_message_size          = -1;
  94
  95         session->avail_auth_type           = 0;
  96         session->forced_auth_type          = 0;
  97         session->auth_type                 = 0;
  98
  99         session->error_val                 = SM_OK;
 100         session->error_msg                 = NULL;
 101
 102         return SESSION(session);
 103 }
 104
 105 static void smtp_session_destroy(Session *session)
 106 {
 107         SMTPSession *smtp_session = SMTP_SESSION(session);
 108
 109         g_free(smtp_session->hostname);
 110         g_free(smtp_session->user);
 111         g_free(smtp_session->pass);
 112         g_free(smtp_session->from);
 113
 114         g_free(smtp_session->send_data);
 115
 116         g_free(smtp_session->error_msg);
 117 }
 118
 119 static gint smtp_from(SMTPSession *session)
 120 {
 121         gchar buf[MSGBUFSIZE];
 122
 123         g_return_val_if_fail(session->from != NULL, SM_ERROR);
 124
 125         session->state = SMTP_FROM;
 126
 127         if (strchr(session->from, '<'))
 128                 g_snprintf(buf, sizeof(buf), "MAIL FROM:%s", session->from);
 129         else
 130                 g_snprintf(buf, sizeof(buf), "MAIL FROM:<%s>", session->from);
 131
 132         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf);
 133         log_print("SMTP> %s\n", buf);
 134
 135         return SM_OK;
 136 }
 137
 138 static gint smtp_auth(SMTPSession *session)
 139 {
 140
 141         g_return_val_if_fail(session->user != NULL, SM_ERROR);
 142
 143         session->state = SMTP_AUTH;
 144
 145         if (session->forced_auth_type == SMTPAUTH_CRAM_MD5 ||
 146             (session->forced_auth_type == 0 &&
 147              (session->avail_auth_type & SMTPAUTH_CRAM_MD5) != 0))
 148                 smtp_auth_cram_md5(session);
 149         else if (session->forced_auth_type == SMTPAUTH_LOGIN ||
 150                  (session->forced_auth_type == 0 &&
 151                   (session->avail_auth_type & SMTPAUTH_LOGIN) != 0))
 152                 smtp_auth_login(session);
 153         else {
 154                 log_warning(_("SMTP AUTH not available\n"));
 155                 return SM_AUTHFAIL;
 156         }
 157
 158         return SM_OK;
 159 }
 160
 161 static gint smtp_auth_recv(SMTPSession *session, const gchar *msg)
 162 {
 163         gchar buf[MSGBUFSIZE];
 164
 165         switch (session->auth_type) {
 166         case SMTPAUTH_LOGIN:
 167                 session->state = SMTP_AUTH_LOGIN_USER;
 168
 169                 if (!strncmp(msg, "334 ", 4)) {
 170                         base64_encode(buf, session->user, strlen(session->user));
 171
 172                         session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
 173                                          buf);
 174                         log_print("ESMTP> [USERID]\n");
 175                 } else {
 176                         /* Server rejects AUTH */
 177                         session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
 178                                          "*");
 179                         log_print("ESMTP> *\n");
 180                 }
 181                 break;
 182         case SMTPAUTH_CRAM_MD5:
 183                 session->state = SMTP_AUTH_CRAM_MD5;
 184
 185                 if (!strncmp(msg, "334 ", 4)) {
 186                         gchar *response;
 187                         gchar *response64;
 188                         gchar *challenge;
 189                         gint challengelen;
 190                         guchar hexdigest[33];
 191
 192                         challenge = g_malloc(strlen(msg + 4) + 1);
 193                         challengelen = base64_decode(challenge, msg + 4, -1);
 194                         challenge[challengelen] = '\0';
 195                         log_print("ESMTP< [Decoded: %s]\n", challenge);
 196
 197                         g_snprintf(buf, sizeof(buf), "%s", session->pass);
 198                         md5_hex_hmac(hexdigest, challenge, challengelen,
 199                                      buf, strlen(session->pass));
 200                         g_free(challenge);
 201
 202                         response = g_strdup_printf
 203                                 ("%s %s", session->user, hexdigest);
 204                         log_print("ESMTP> [Encoded: %s]\n", response);
 205
 206                         response64 = g_malloc((strlen(response) + 3) * 2 + 1);
 207                         base64_encode(response64, response, strlen(response));
 208                         g_free(response);
 209
 210                         session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
 211                                          response64);
 212                         log_print("ESMTP> %s\n", response64);
 213                         g_free(response64);
 214                 } else {
 215                         /* Server rejects AUTH */
 216                         session_send_msg(SESSION(session), SESSION_MSG_NORMAL,
 217                                          "*");
 218                         log_print("ESMTP> *\n");
 219                 }
 220                 break;
 221         case SMTPAUTH_DIGEST_MD5:
 222         default:
 223                 /* stop smtp_auth when no correct authtype */
 224                 session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "*");
 225                 log_print("ESMTP> *\n");
 226                 break;
 227         }
 228
 229         return SM_OK;
 230 }
 231
 232 static gint smtp_auth_login_user_recv(SMTPSession *session, const gchar *msg)
 233 {
 234         gchar buf[MSGBUFSIZE];
 235
 236         session->state = SMTP_AUTH_LOGIN_PASS;
 237
 238         if (!strncmp(msg, "334 ", 4))
 239                 base64_encode(buf, session->pass, strlen(session->pass));
 240         else
 241                 /* Server rejects AUTH */
 242                 g_snprintf(buf, sizeof(buf), "*");
 243
 244         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf);
 245         log_print("ESMTP> [PASSWORD]\n");
 246
 247         return SM_OK;
 248 }
 249
 250 static gint smtp_ehlo(SMTPSession *session)
 251 {
 252         gchar buf[MSGBUFSIZE];
 253
 254         session->state = SMTP_EHLO;
 255
 256         session->avail_auth_type = 0;
 257
 258         g_snprintf(buf, sizeof(buf), "EHLO %s",
 259                    session->hostname ? session->hostname : get_domain_name());
 260         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf);
 261         log_print("ESMTP> %s\n", buf);
 262
 263         return SM_OK;
 264 }
 265
 266 static gint smtp_ehlo_recv(SMTPSession *session, const gchar *msg)
 267 {
 268         if (strncmp(msg, "250", 3) == 0) {
 269                 const gchar *p = msg;
 270                 p += 3;
 271                 if (*p == '-' || *p == ' ') p++;
 272                 if (g_strncasecmp(p, "AUTH", 4) == 0) {
 273                         p += 5;
 274                         if (strcasestr(p, "LOGIN"))
 275                                 session->avail_auth_type |= SMTPAUTH_LOGIN;
 276                         if (strcasestr(p, "CRAM-MD5"))
 277                                 session->avail_auth_type |= SMTPAUTH_CRAM_MD5;
 278                         if (strcasestr(p, "DIGEST-MD5"))
 279                                 session->avail_auth_type |= SMTPAUTH_DIGEST_MD5;
 280                 }
 281                 if (g_strncasecmp(p, "SIZE", 4) == 0) {
 282                         p += 5;
 283                         session->max_message_size = atoi(p);
 284                 }
 285                 return SM_OK;
 286         } else if ((msg[0] == '1' || msg[0] == '2' || msg[0] == '3') &&
 287             (msg[3] == ' ' || msg[3] == '\0'))
 288                 return SM_OK;
 289         else if (msg[0] == '5' && msg[1] == '0' &&
 290                  (msg[2] == '4' || msg[2] == '3' || msg[2] == '1'))
 291                 return SM_ERROR;
 292
 293         return SM_ERROR;
 294 }
 295
 296 static gint smtp_starttls(SMTPSession *session)
 297 {
 298         session->state = SMTP_STARTTLS;
 299
 300         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "STARTTLS");
 301         log_print("ESMTP> STARTTLS\n");
 302
 303         return SM_OK;
 304 }
 305
 306 static gint smtp_auth_cram_md5(SMTPSession *session)
 307 {
 308         session->state = SMTP_AUTH;
 309         session->auth_type = SMTPAUTH_CRAM_MD5;
 310
 311         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "AUTH CRAM-MD5");
 312         log_print("ESMTP> AUTH CRAM-MD5\n");
 313
 314         return SM_OK;
 315 }
 316
 317 static gint smtp_auth_login(SMTPSession *session)
 318 {
 319         session->state = SMTP_AUTH;
 320         session->auth_type = SMTPAUTH_LOGIN;
 321
 322         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "AUTH LOGIN");
 323         log_print("ESMTP> AUTH LOGIN\n");
 324
 325         return SM_OK;
 326 }
 327
 328 static gint smtp_helo(SMTPSession *session)
 329 {
 330         gchar buf[MSGBUFSIZE];
 331
 332         session->state = SMTP_HELO;
 333
 334         g_snprintf(buf, sizeof(buf), "HELO %s",
 335                    session->hostname ? session->hostname : get_domain_name());
 336         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf);
 337         log_print("SMTP> %s\n", buf);
 338
 339         return SM_OK;
 340 }
 341
 342 static gint smtp_rcpt(SMTPSession *session)
 343 {
 344         gchar buf[MSGBUFSIZE];
 345         gchar *to;
 346
 347         g_return_val_if_fail(session->cur_to != NULL, SM_ERROR);
 348
 349         session->state = SMTP_RCPT;
 350
 351         to = (gchar *)session->cur_to->data;
 352
 353         if (strchr(to, '<'))
 354                 g_snprintf(buf, sizeof(buf), "RCPT TO:%s", to);
 355         else
 356                 g_snprintf(buf, sizeof(buf), "RCPT TO:<%s>", to);
 357         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, buf);
 358         log_print("SMTP> %s\n", buf);
 359
 360         session->cur_to = session->cur_to->next;
 361
 362         return SM_OK;
 363 }
 364
 365 static gint smtp_data(SMTPSession *session)
 366 {
 367         session->state = SMTP_DATA;
 368
 369         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "DATA");
 370         log_print("SMTP> DATA\n");
 371
 372         return SM_OK;
 373 }
 374
 375 static gint smtp_send_data(SMTPSession *session)
 376 {
 377         session->state = SMTP_SEND_DATA;
 378
 379         session_send_data(SESSION(session), session->send_data,
 380                           session->send_data_len);
 381
 382         return SM_OK;
 383 }
 384
 385 #if 0
 386 static gint smtp_rset(SMTPSession *session)
 387 {
 388         session->state = SMTP_RSET;
 389
 390         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "RSET");
 391         log_print("SMTP> RSET\n");
 392
 393         return SM_OK;
 394 }
 395 #endif
 396
 397 static gint smtp_quit(SMTPSession *session)
 398 {
 399         session->state = SMTP_QUIT;
 400
 401         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, "QUIT");
 402         log_print("SMTP> QUIT\n");
 403
 404         return SM_OK;
 405 }
 406
 407 static gint smtp_eom(SMTPSession *session)
 408 {
 409         session->state = SMTP_EOM;
 410
 411         session_send_msg(SESSION(session), SESSION_MSG_NORMAL, ".");
 412         log_print("SMTP> . (EOM)\n");
 413
 414         return SM_OK;
 415 }
 416
 417 static gint smtp_session_recv_msg(Session *session, const gchar *msg)
 418 {
 419         SMTPSession *smtp_session = SMTP_SESSION(session);
 420         gboolean cont = FALSE;
 421
 422         if (strlen(msg) < 4) {
 423                 log_warning(_("bad SMTP response\n"));
 424                 return -1;
 425         }
 426
 427         switch (smtp_session->state) {
 428         case SMTP_EHLO:
 429         case SMTP_STARTTLS:
 430         case SMTP_AUTH:
 431         case SMTP_AUTH_LOGIN_USER:
 432         case SMTP_AUTH_LOGIN_PASS:
 433         case SMTP_AUTH_CRAM_MD5:
 434                 log_print("ESMTP< %s\n", msg);
 435                 break;
 436         default:
 437                 log_print("SMTP< %s\n", msg);
 438                 break;
 439         }
 440
 441         if (msg[0] == '5' && msg[1] == '0' &&
 442             (msg[2] == '4' || msg[2] == '3' || msg[2] == '1')) {
 443                 log_warning(_("error occurred on SMTP session\n"));
 444                 smtp_session->state = SMTP_ERROR;
 445                 smtp_session->error_val = SM_ERROR;
 446                 g_free(smtp_session->error_msg);
 447                 smtp_session->error_msg = g_strdup(msg);
 448                 return -1;
 449         }
 450
 451         if (!strncmp(msg, "535", 3)) {
 452                 log_warning(_("error occurred on authentication\n"));
 453                 smtp_session->state = SMTP_ERROR;
 454                 smtp_session->error_val = SM_AUTHFAIL;
 455                 g_free(smtp_session->error_msg);
 456                 smtp_session->error_msg = g_strdup(msg);
 457                 return -1;
 458         }
 459
 460         if (msg[0] != '1' && msg[0] != '2' && msg[0] != '3') {
 461                 log_warning(_("error occurred on SMTP session\n"));
 462                 smtp_session->state = SMTP_ERROR;
 463                 smtp_session->error_val = SM_ERROR;
 464                 g_free(smtp_session->error_msg);
 465                 smtp_session->error_msg = g_strdup(msg);
 466                 return -1;
 467         }
 468
 469         if (msg[3] == '-')
 470                 cont = TRUE;
 471         else if (msg[3] != ' ' && msg[3] != '\0') {
 472                 log_warning(_("bad SMTP response\n"));
 473                 smtp_session->state = SMTP_ERROR;
 474                 smtp_session->error_val = SM_UNRECOVERABLE;
 475                 return -1;
 476         }
 477
 478         /* ignore all multiline responses except for EHLO */
 479         if (cont && smtp_session->state != SMTP_EHLO)
 480                 return session_recv_msg(session);
 481
 482         switch (smtp_session->state) {
 483         case SMTP_READY:
 484         case SMTP_CONNECTED:
 485 #if USE_OPENSSL
 486                 if (smtp_session->user || session->ssl_type != SSL_NONE)
 487 #else
 488                 if (smtp_session->user)
 489 #endif
 490                         smtp_ehlo(smtp_session);
 491                 else
 492                         smtp_helo(smtp_session);
 493                 break;
 494         case SMTP_HELO:
 495                 smtp_from(smtp_session);
 496                 break;
 497         case SMTP_EHLO:
 498                 smtp_ehlo_recv(smtp_session, msg);
 499                 if (cont == TRUE)
 500                         break;
 501                 if (smtp_session->max_message_size > 0
 502                 && smtp_session->max_message_size < smtp_session->send_data_len) {
 503                         log_warning(_("Message is too big "
 504                               "(Maximum size is %s)\n"),
 505                               to_human_readable(
 506                                (off_t)(smtp_session->max_message_size / 1024)));
 507
 508                         smtp_session->state = SMTP_ERROR;
 509                         smtp_session->error_val = SM_ERROR;
 510                         return -1;
 511                 }
 512 #if USE_OPENSSL
 513                 if (session->ssl_type == SSL_STARTTLS &&
 514                     smtp_session->tls_init_done == FALSE) {
 515                         smtp_starttls(smtp_session);
 516                         break;
 517                 }
 518 #endif
 519                 if (smtp_session->user) {
 520                         if (smtp_auth(smtp_session) != SM_OK)
 521                                 smtp_from(smtp_session);
 522                 } else
 523                         smtp_from(smtp_session);
 524                 break;
 525         case SMTP_STARTTLS:
 526 #if USE_OPENSSL
 527                 if (session_start_tls(session) < 0) {
 528                         log_warning(_("can't start TLS session\n"));
 529                         smtp_session->state = SMTP_ERROR;
 530                         smtp_session->error_val = SM_ERROR;
 531                         return -1;
 532                 }
 533                 smtp_session->tls_init_done = TRUE;
 534                 smtp_ehlo(smtp_session);
 535 #endif
 536                 break;
 537         case SMTP_AUTH:
 538                 smtp_auth_recv(smtp_session, msg);
 539                 break;
 540         case SMTP_AUTH_LOGIN_USER:
 541                 smtp_auth_login_user_recv(smtp_session, msg);
 542                 break;
 543         case SMTP_AUTH_LOGIN_PASS:
 544         case SMTP_AUTH_CRAM_MD5:
 545                 smtp_from(smtp_session);
 546                 break;
 547         case SMTP_FROM:
 548                 if (smtp_session->cur_to)
 549                         smtp_rcpt(smtp_session);
 550                 break;
 551         case SMTP_RCPT:
 552                 if (smtp_session->cur_to)
 553                         smtp_rcpt(smtp_session);
 554                 else
 555                         smtp_data(smtp_session);
 556                 break;
 557         case SMTP_DATA:
 558                 smtp_send_data(smtp_session);
 559                 break;
 560         case SMTP_EOM:
 561                 smtp_quit(smtp_session);
 562                 break;
 563         case SMTP_QUIT:
 564                 session_disconnect(session);
 565                 break;
 566         case SMTP_ERROR:
 567         default:
 568                 log_warning(_("error occurred on SMTP session\n"));
 569                 smtp_session->error_val = SM_ERROR;
 570                 return -1;
 571         }
 572
 573         if (cont)
 574                 return session_recv_msg(session);
 575
 576         return 0;
 577 }
 578
 579 static gint smtp_session_send_data_finished(Session *session, guint len)
 580 {
 581         smtp_eom(SMTP_SESSION(session));
 582         return 0;
 583 }