src/plugins/spamassassin/spamassassin.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2006 Hiroyuki Yamamoto and the Sylpheed-Claws Team
   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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #  include "config.h"
  22 #endif
  23
  24 #include "defs.h"
  25
  26 #include <sys/types.h>
  27 #include <sys/wait.h>
  28
  29 #include <glib.h>
  30 #include <glib/gi18n.h>
  31
  32 #if HAVE_LOCALE_H
  33 #  include <locale.h>
  34 #endif
  35
  36 #include "common/sylpheed.h"
  37 #include "common/version.h"
  38 #include "plugin.h"
  39 #include "common/utils.h"
  40 #include "hooks.h"
  41 #include "procmsg.h"
  42 #include "folder.h"
  43 #include "prefs.h"
  44 #include "prefs_gtk.h"
  45
  46 #include "libspamc.h"
  47 #include "spamassassin.h"
  48 #include "inc.h"
  49 #include "log.h"
  50 #include "prefs_common.h"
  51 #include "alertpanel.h"
  52
  53 #ifdef HAVE_SYSEXITS_H
  54 #include <sysexits.h>
  55 #endif
  56 #ifdef HAVE_ERRNO_H
  57 #include <errno.h>
  58 #endif
  59 #ifdef HAVE_SYS_ERRNO_H
  60 #include <sys/errno.h>
  61 #endif
  62 #ifdef HAVE_TIME_H
  63 #include <time.h>
  64 #endif
  65 #ifdef HAVE_SYS_TIME_H
  66 #include <sys/time.h>
  67 #endif
  68 #ifdef HAVE_SIGNAL_H
  69 #include <signal.h>
  70 #endif
  71 #ifdef HAVE_PWD_H
  72 #include <pwd.h>
  73 #endif
  74
  75 enum {
  76     CHILD_RUNNING = 1 << 0,
  77     TIMEOUT_RUNNING = 1 << 1,
  78 };
  79
  80 static guint hook_id = -1;
  81 static int flags = SPAMC_RAW_MODE | SPAMC_SAFE_FALLBACK | SPAMC_CHECK_ONLY;
  82 static MessageCallback message_callback;
  83
  84 static SpamAssassinConfig config;
  85
  86 static PrefParam param[] = {
  87         {"enable", "FALSE", &config.enable, P_BOOL,
  88         NULL, NULL, NULL},
  89         {"transport", "0", &config.transport, P_INT,
  90          NULL, NULL, NULL},
  91         {"hostname", "localhost", &config.hostname, P_STRING,
  92          NULL, NULL, NULL},
  93         {"port", "783", &config.port, P_INT,
  94          NULL, NULL, NULL},
  95         {"socket", "", &config.socket, P_STRING,
  96          NULL, NULL, NULL},
  97         {"process_emails", "TRUE", &config.process_emails, P_BOOL,
  98          NULL, NULL, NULL},
  99         {"receive_spam", "TRUE", &config.receive_spam, P_BOOL,
 100          NULL, NULL, NULL},
 101         {"save_folder", NULL, &config.save_folder, P_STRING,
 102          NULL, NULL, NULL},
 103         {"max_size", "250", &config.max_size, P_INT,
 104          NULL, NULL, NULL},
 105         {"timeout", "30", &config.timeout, P_INT,
 106          NULL, NULL, NULL},
 107         {"username", "", &config.username, P_STRING,
 108          NULL, NULL, NULL},
 109
 110         {NULL, NULL, NULL, P_OTHER, NULL, NULL, NULL}
 111 };
 112
 113 gboolean timeout_func(gpointer data)
 114 {
 115         gint *running = (gint *) data;
 116
 117         if (*running & CHILD_RUNNING)
 118                 return TRUE;
 119
 120         *running &= ~TIMEOUT_RUNNING;
 121         return FALSE;
 122 }
 123
 124 typedef enum {
 125         MSG_IS_HAM = 0,
 126         MSG_IS_SPAM = 1,
 127         MSG_FILTERING_ERROR = 2
 128 } MsgStatus;
 129
 130 static MsgStatus msg_is_spam(FILE *fp)
 131 {
 132         struct transport trans;
 133         struct message m;
 134         gboolean is_spam = FALSE;
 135
 136         if (!config.enable)
 137                 return MSG_IS_HAM;
 138
 139         transport_init(&trans);
 140         switch (config.transport) {
 141         case SPAMASSASSIN_TRANSPORT_LOCALHOST:
 142                 trans.type = TRANSPORT_LOCALHOST;
 143                 trans.port = config.port;
 144                 break;
 145         case SPAMASSASSIN_TRANSPORT_TCP:
 146                 trans.type = TRANSPORT_TCP;
 147                 trans.hostname = config.hostname;
 148                 trans.port = config.port;
 149                 break;
 150         case SPAMASSASSIN_TRANSPORT_UNIX:
 151                 trans.type = TRANSPORT_UNIX;
 152                 trans.socketpath = config.socket;
 153                 break;
 154         default:
 155                 return MSG_IS_HAM;
 156         }
 157
 158         if (transport_setup(&trans, flags) != EX_OK) {
 159                 log_error(_("SpamAssassin plugin couldn't connect to spamd.\n"));
 160                 debug_print("failed to setup transport\n");
 161                 return MSG_FILTERING_ERROR;
 162         }
 163
 164         m.type = MESSAGE_NONE;
 165         m.max_len = config.max_size * 1024;
 166         m.timeout = config.timeout;
 167
 168         if (message_read(fileno(fp), flags, &m) != EX_OK) {
 169                 debug_print("failed to read message\n");
 170                 message_cleanup(&m);
 171                 return MSG_FILTERING_ERROR;
 172         }
 173
 174         if (message_filter(&trans, config.username, flags, &m) != EX_OK) {
 175                 log_error(_("SpamAssassin plugin filtering failed.\n"));
 176                 debug_print("filtering the message failed\n");
 177                 message_cleanup(&m);
 178                 return MSG_FILTERING_ERROR;
 179         }
 180
 181         if (m.is_spam == EX_ISSPAM)
 182                 is_spam = TRUE;
 183
 184         message_cleanup(&m);
 185
 186         return is_spam ? MSG_IS_SPAM:MSG_IS_HAM;
 187 }
 188
 189 static gboolean mail_filtering_hook(gpointer source, gpointer data)
 190 {
 191         MailFilteringData *mail_filtering_data = (MailFilteringData *) source;
 192         MsgInfo *msginfo = mail_filtering_data->msginfo;
 193         gboolean is_spam = FALSE, error = FALSE;
 194         static gboolean warned_error = FALSE;
 195         FILE *fp = NULL;
 196         int pid = 0;
 197         int status;
 198
 199         /* SPAMASSASSIN_DISABLED : keep test for compatibility purpose */
 200         if (!config.enable || config.transport == SPAMASSASSIN_DISABLED) {
 201                 log_error(_("SpamAssassin plugin is disabled by its preferences.\n"));
 202                 return FALSE;
 203         }
 204         debug_print("Filtering message %d\n", msginfo->msgnum);
 205         if (message_callback != NULL)
 206                 message_callback(_("SpamAssassin: filtering message..."));
 207
 208         if ((fp = procmsg_open_message(msginfo)) == NULL) {
 209                 debug_print("failed to open message file\n");
 210                 return FALSE;
 211         }
 212
 213         pid = fork();
 214         if (pid == 0) {
 215                 _exit(msg_is_spam(fp));
 216         } else {
 217                 gint running = 0;
 218
 219                 running |= CHILD_RUNNING;
 220
 221                 g_timeout_add(50, timeout_func, &running);
 222                 running |= TIMEOUT_RUNNING;
 223
 224                 while(running & CHILD_RUNNING) {
 225                         int ret;
 226
 227                         ret = waitpid(pid, &status, WNOHANG);
 228                         if (ret == pid) {
 229                                 if (WIFEXITED(status)) {
 230                                         MsgStatus result = MSG_IS_HAM;
 231                                         running &= ~CHILD_RUNNING;
 232                                         result = WEXITSTATUS(status);
 233                                         is_spam = (result == MSG_IS_SPAM) ? TRUE : FALSE;
 234                                         error = (result == MSG_FILTERING_ERROR);
 235                                 }
 236                         } if (ret < 0) {
 237                                 running &= ~CHILD_RUNNING;
 238                         } /* ret == 0 continue */
 239
 240                         g_main_iteration(TRUE);
 241                 }
 242
 243                 while (running & TIMEOUT_RUNNING)
 244                         g_main_iteration(TRUE);
 245         }
 246
 247         fclose(fp);
 248
 249         if (is_spam) {
 250                 debug_print("message is spam\n");
 251                 procmsg_msginfo_set_flags(msginfo, MSG_SPAM, 0);
 252                 if (config.receive_spam) {
 253                         FolderItem *save_folder;
 254
 255                         if ((!config.save_folder) ||
 256                             (config.save_folder[0] == '\0') ||
 257                             ((save_folder = folder_find_item_from_identifier(config.save_folder)) == NULL))
 258                                 save_folder = folder_get_default_trash();
 259
 260                         procmsg_msginfo_unset_flags(msginfo, ~0, 0);
 261                         procmsg_msginfo_set_flags(msginfo, MSG_SPAM, 0);
 262                         folder_item_move_msg(save_folder, msginfo);
 263                 } else {
 264                         folder_item_remove_msg(msginfo->folder, msginfo->msgnum);
 265                 }
 266
 267                 return TRUE;
 268         } else {
 269                 debug_print("message is ham\n");
 270                 procmsg_msginfo_unset_flags(msginfo, MSG_SPAM, 0);
 271         }
 272
 273         if (error) {
 274                 if (!warned_error) {
 275                         alertpanel_error(_("The SpamAssassin plugin couldn't filter "
 276                                            "a message. The probable error cause is "
 277                                            "an unreachable spamd daemon. Please make "
 278                                            "sure spamd is running and accessible."));
 279                 }
 280                 warned_error = TRUE;
 281         }
 282
 283         return FALSE;
 284 }
 285
 286 SpamAssassinConfig *spamassassin_get_config(void)
 287 {
 288         return &config;
 289 }
 290
 291 gchar* spamassassin_create_tmp_spamc_wrapper(gboolean spam)
 292 {
 293         gchar *contents;
 294         gchar *fname = get_tmp_file();
 295
 296         if (fname != NULL) {
 297                 contents = g_strdup_printf(
 298                                                 "spamc -d %s -p %u -u %s -t %u -s %u -L %s<\"$*\";exit $?",
 299                                                 config.hostname, config.port,
 300                                                 config.username, config.timeout,
 301                                                 config.max_size * 1024, spam?"spam":"ham");
 302                 if (str_write_to_file(contents, fname) < 0) {
 303                         g_free(fname);
 304                         fname = NULL;
 305                 }
 306                 g_free(contents);
 307         }
 308         /* returned pointer must be free'ed by caller */
 309         return fname;
 310 }
 311
 312 int spamassassin_learn(MsgInfo *msginfo, GSList *msglist, gboolean spam)
 313 {
 314         gchar *cmd = NULL;
 315         gchar *file = NULL;
 316         const gchar *shell = g_getenv("SHELL");
 317         gchar *spamc_wrapper = NULL;
 318
 319         if (msginfo == NULL && msglist == NULL) {
 320                 return -1;
 321         }
 322
 323         if (config.transport == SPAMASSASSIN_TRANSPORT_TCP
 324         &&  prefs_common.work_offline
 325         &&  !inc_offline_should_override(
 326                 _("Sylpheed-Claws needs network access in order "
 327                   "to feed this mail(s) to the remote learner."))) {
 328                 return -1;
 329         }
 330
 331         if (msginfo) {
 332                 file = procmsg_get_message_file(msginfo);
 333                 if (file == NULL) {
 334                         return -1;
 335                 }
 336                 if (config.transport == SPAMASSASSIN_TRANSPORT_TCP) {
 337                         spamc_wrapper = spamassassin_create_tmp_spamc_wrapper(spam);
 338                         if (spamc_wrapper != NULL) {
 339                                 cmd = g_strconcat(shell?shell:"sh", " ",
 340                                                                 spamc_wrapper, " ", file, NULL);
 341                         }
 342                 } else {
 343                         cmd = g_strdup_printf("sa-learn -u %s %s %s %s",
 344                                                         config.username,
 345                                                         prefs_common.work_offline?"-L":"",
 346                                                         spam?"--spam":"--ham", file);
 347                 }
 348         }
 349         if (msglist) {
 350                 GSList *cur = msglist;
 351                 MsgInfo *info;
 352
 353                 if (config.transport == SPAMASSASSIN_TRANSPORT_TCP) {
 354                         /* execute n-times the spamc command */
 355                         for (; cur; cur = cur->next) {
 356                                 info = (MsgInfo *)cur->data;
 357                                 gchar *tmpcmd = NULL;
 358                                 gchar *tmpfile = get_tmp_file();
 359
 360                                 if (spamc_wrapper == NULL) {
 361                                         spamc_wrapper = spamassassin_create_tmp_spamc_wrapper(spam);
 362                                 }
 363
 364                                 if (spamc_wrapper && tmpfile &&
 365                                 copy_file(procmsg_get_message_file(info), tmpfile, TRUE) == 0) {
 366                                         tmpcmd = g_strconcat(shell?shell:"sh", " ", spamc_wrapper, " ",
 367                                                                                 tmpfile, NULL);
 368                                         debug_print("%s\n", tmpcmd);
 369                                         execute_command_line(tmpcmd, FALSE);
 370                                         g_free(tmpcmd);
 371                                 }
 372                                 g_free(tmpfile);
 373                         }
 374                         g_free(spamc_wrapper);
 375                         return 0;
 376                 } else {
 377                         cmd = g_strdup_printf("sa-learn -u %s %s %s",
 378                                         config.username,
 379                                         prefs_common.work_offline?"-L":"",
 380                                         spam?"--spam":"--ham");
 381
 382                         /* concatenate all message tmpfiles to the sa-learn command-line */
 383                         for (; cur; cur = cur->next) {
 384                                 info = (MsgInfo *)cur->data;
 385                                 gchar *tmpcmd = NULL;
 386                                 gchar *tmpfile = get_tmp_file();
 387
 388                                 if (tmpfile &&
 389                                 copy_file(procmsg_get_message_file(info), tmpfile, TRUE) == 0) {
 390                                         tmpcmd = g_strconcat(cmd, " ", tmpfile, NULL);
 391                                         g_free(cmd);
 392                                         cmd = tmpcmd;
 393                                 }
 394                                 g_free(tmpfile);
 395                         }
 396                 }
 397         }
 398         if (cmd == NULL) {
 399                 return -1;
 400         }
 401         debug_print("%s\n", cmd);
 402         /* only run sync calls to sa-learn/spamc to prevent system lockdown */
 403         execute_command_line(cmd, FALSE);
 404         g_free(cmd);
 405         g_free(spamc_wrapper);
 406
 407         return 0;
 408 }
 409
 410 void spamassassin_save_config(void)
 411 {
 412         PrefFile *pfile;
 413         gchar *rcpath;
 414
 415         debug_print("Saving SpamAssassin Page\n");
 416
 417         rcpath = g_strconcat(get_rc_dir(), G_DIR_SEPARATOR_S, COMMON_RC, NULL);
 418         pfile = prefs_write_open(rcpath);
 419         g_free(rcpath);
 420         if (!pfile || (prefs_set_block_label(pfile, "SpamAssassin") < 0))
 421                 return;
 422
 423         if (prefs_write_param(param, pfile->fp) < 0) {
 424                 g_warning("Failed to write SpamAssassin configuration to file\n");
 425                 prefs_file_close_revert(pfile);
 426                 return;
 427         }
 428         fprintf(pfile->fp, "\n");
 429
 430         prefs_file_close(pfile);
 431 }
 432
 433 gboolean spamassassin_check_username(void)
 434 {
 435         if (config.username == NULL || config.username[0] == '\0') {
 436                 config.username = (gchar*)g_get_user_name();
 437                 if (config.username == NULL) {
 438                         if (hook_id != -1) {
 439                                 spamassassin_unregister_hook();
 440                         }
 441                         procmsg_unregister_spam_learner(spamassassin_learn);
 442                         procmsg_spam_set_folder(NULL);
 443                         return FALSE;
 444                 }
 445         }
 446         return TRUE;
 447 }
 448
 449 void spamassassin_set_message_callback(MessageCallback callback)
 450 {
 451         message_callback = callback;
 452 }
 453
 454 gint plugin_init(gchar **error)
 455 {
 456         gchar *rcpath;
 457
 458         hook_id = -1;
 459
 460         if ((sylpheed_get_version() > VERSION_NUMERIC)) {
 461                 *error = g_strdup("Your version of Sylpheed-Claws is newer than the version the SpamAssassin plugin was built with");
 462                 return -1;
 463         }
 464
 465         if ((sylpheed_get_version() < MAKE_NUMERIC_VERSION(0, 9, 3, 86))) {
 466                 *error = g_strdup("Your version of Sylpheed-Claws is too old for the SpamAssassin plugin");
 467                 return -1;
 468         }
 469
 470         prefs_set_default(param);
 471         rcpath = g_strconcat(get_rc_dir(), G_DIR_SEPARATOR_S, COMMON_RC, NULL);
 472         prefs_read_config(param, "SpamAssassin", rcpath, NULL);
 473         g_free(rcpath);
 474         if (!spamassassin_check_username()) {
 475                 *error = g_strdup("Failed to get username");
 476                 return -1;
 477         }
 478         spamassassin_gtk_init();
 479
 480         debug_print("SpamAssassin plugin loaded\n");
 481
 482         if (config.process_emails) {
 483                 spamassassin_register_hook();
 484         }
 485
 486         if (!config.enable || config.transport == SPAMASSASSIN_DISABLED) {
 487                 log_error(_("SpamAssassin plugin is loaded but disabled by its preferences.\n"));
 488         }
 489         else {
 490                 if (config.transport == SPAMASSASSIN_TRANSPORT_TCP)
 491                         debug_print("Enabling learner with a remote spamassassin server requires spamc/spamd 3.1.x\n");
 492                 procmsg_register_spam_learner(spamassassin_learn);
 493                 procmsg_spam_set_folder(config.save_folder);
 494         }
 495
 496         return 0;
 497
 498 }
 499
 500 void plugin_done(void)
 501 {
 502         if (hook_id != -1) {
 503                 spamassassin_unregister_hook();
 504         }
 505         g_free(config.hostname);
 506         g_free(config.save_folder);
 507         spamassassin_gtk_done();
 508         procmsg_unregister_spam_learner(spamassassin_learn);
 509         procmsg_spam_set_folder(NULL);
 510         debug_print("SpamAssassin plugin unloaded\n");
 511 }
 512
 513 const gchar *plugin_name(void)
 514 {
 515         return _("SpamAssassin");
 516 }
 517
 518 const gchar *plugin_desc(void)
 519 {
 520         return _("This plugin can check all messages that are received from an "
 521                  "IMAP, LOCAL or POP account for spam using a SpamAssassin "
 522                  "server. You will need a SpamAssassin Server (spamd) running "
 523                  "somewhere.\n"
 524                  "\n"
 525                  "It can also be used for marking messages as Ham or Spam.\n"
 526                  "\n"
 527                  "When a message is identified as spam it can be deleted or "
 528                  "saved in a specially designated folder.\n"
 529                  "\n"
 530                  "Options can be found in /Configuration/Preferences/Plugins/SpamAssassin");
 531 }
 532
 533 const gchar *plugin_type(void)
 534 {
 535         return "GTK2";
 536 }
 537
 538 const gchar *plugin_licence(void)
 539 {
 540         return "GPL";
 541 }
 542
 543 const gchar *plugin_version(void)
 544 {
 545         return VERSION;
 546 }
 547
 548 struct PluginFeature *plugin_provides(void)
 549 {
 550         static struct PluginFeature features[] =
 551                 { {PLUGIN_FILTERING, N_("Spam detection")},
 552                   {PLUGIN_FILTERING, N_("Spam learning")},
 553                   {PLUGIN_NOTHING, NULL}};
 554         return features;
 555 }
 556
 557 void spamassassin_register_hook(void)
 558 {
 559         hook_id = hooks_register_hook(MAIL_FILTERING_HOOKLIST, mail_filtering_hook, NULL);
 560         if (hook_id == -1) {
 561                 g_warning("Failed to register mail filtering hook");
 562                 config.process_emails = FALSE;
 563         }
 564 }
 565
 566 void spamassassin_unregister_hook(void)
 567 {
 568         if (hook_id != -1) {
 569                 hooks_unregister_hook(MAIL_FILTERING_HOOKLIST, hook_id);
 570         }
 571 }