src/privacy.c

   1 /*
   2  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2009 Hiroyuki Yamamoto & the Claws Mail 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 3 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, see <http://www.gnu.org/licenses/>.
  17  *
  18  */
  19
  20 #include <glib.h>
  21 #include <glib/gi18n.h>
  22
  23 #include "privacy.h"
  24 #include "procmime.h"
  25
  26 static GSList *systems = NULL;
  27 static gchar *privacy_last_error = NULL;
  28
  29 void privacy_set_error(const gchar *format, ...)
  30 {
  31         va_list args;
  32         gchar buf[BUFSIZ];
  33
  34         va_start(args, format);
  35         g_vsnprintf(buf, BUFSIZ, format, args);
  36         va_end(args);
  37         g_free(privacy_last_error);
  38         privacy_last_error = g_strdup(buf);
  39 }
  40
  41 static gchar tmp_privacy_error[BUFSIZ];
  42
  43 void privacy_reset_error(void)
  44 {
  45         g_free(privacy_last_error);
  46         privacy_last_error = NULL;
  47 }
  48
  49 gboolean privacy_peek_error(void)
  50 {
  51         return (privacy_last_error != NULL);
  52 }
  53
  54 const gchar *privacy_get_error (void)
  55 {
  56         if (privacy_last_error) {
  57                 strncpy2(tmp_privacy_error, privacy_last_error, BUFSIZ-1);
  58                 privacy_reset_error();
  59                 return tmp_privacy_error;
  60         } else {
  61                 return _("Unknown error");
  62         }
  63 }
  64
  65 static PrivacySystem *privacy_data_get_system(PrivacyData *data)
  66 {
  67         /* Make sure the cached system is still registered */
  68         if (data->system && g_slist_find(systems, data->system))
  69                 return data->system;
  70         else
  71                 return NULL;
  72 }
  73 /**
  74  * Register a new Privacy System
  75  *
  76  * \param system The Privacy System that should be registered
  77  */
  78 void privacy_register_system(PrivacySystem *system)
  79 {
  80         systems = g_slist_append(systems, system);
  81 }
  82
  83 /**
  84  * Unregister a new Privacy System. The system must not be in
  85  * use anymore when it is unregistered.
  86  *
  87  * \param system The Privacy System that should be unregistered
  88  */
  89 void privacy_unregister_system(PrivacySystem *system)
  90 {
  91         systems = g_slist_remove(systems, system);
  92 }
  93
  94 /**
  95  * Free a PrivacyData of a PrivacySystem
  96  *
  97  * \param privacydata The data to free
  98  */
  99 void privacy_free_privacydata(PrivacyData *privacydata)
 100 {
 101         PrivacySystem *system = NULL;
 102
 103         cm_return_if_fail(privacydata != NULL);
 104
 105         system = privacy_data_get_system(privacydata);
 106         if (!system)
 107                 return;
 108         system->free_privacydata(privacydata);
 109 }
 110
 111 /**
 112  * Check if a MimeInfo is signed with one of the available
 113  * privacy system. If a privacydata is set in the MimeInfo
 114  * it will directory return the return value by the system
 115  * set in the privacy data or check all available privacy
 116  * systems otherwise.
 117  *
 118  * \return True if the MimeInfo has a signature
 119  */
 120 gboolean privacy_mimeinfo_is_signed(MimeInfo *mimeinfo)
 121 {
 122         GSList *cur;
 123         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 124
 125         if (mimeinfo->privacy != NULL) {
 126                 PrivacySystem *system =
 127                         privacy_data_get_system(mimeinfo->privacy);
 128
 129                 if (system == NULL) {
 130                         mimeinfo->privacy = NULL;
 131                         goto try_others;
 132                 }
 133
 134                 if (system->is_signed != NULL)
 135                         return system->is_signed(mimeinfo);
 136                 else
 137                         return FALSE;
 138         }
 139 try_others:
 140         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 141                 PrivacySystem *system = (PrivacySystem *) cur->data;
 142
 143                 if(system->is_signed != NULL && system->is_signed(mimeinfo))
 144                         return TRUE;
 145         }
 146
 147         return FALSE;
 148 }
 149
 150 struct SignedState {
 151         MsgInfo *msginfo;
 152         gchar **system;
 153 };
 154
 155 static void msginfo_set_signed_flag(GNode *node, gpointer data)
 156 {
 157         struct SignedState *sstate = (struct SignedState *)data;
 158         MsgInfo *msginfo = sstate->msginfo;
 159         MimeInfo *mimeinfo = node->data;
 160
 161         if (privacy_mimeinfo_is_signed(mimeinfo)) {
 162                 procmsg_msginfo_set_flags(msginfo, 0, MSG_SIGNED);
 163                 if (sstate->system && !*(sstate->system) && mimeinfo->privacy)
 164                         *(sstate->system) = g_strdup(mimeinfo->privacy->system->id);
 165         }
 166         if (privacy_mimeinfo_is_encrypted(mimeinfo)) {
 167                 procmsg_msginfo_set_flags(msginfo, 0, MSG_ENCRYPTED);
 168                 if (sstate->system && !*(sstate->system) && mimeinfo->privacy)
 169                         *(sstate->system) = g_strdup(mimeinfo->privacy->system->id);
 170         } else {
 171                 /* searching inside encrypted parts doesn't really make sense */
 172                 g_node_children_foreach(mimeinfo->node, G_TRAVERSE_ALL, msginfo_set_signed_flag, sstate);
 173         }
 174 }
 175
 176 void privacy_msginfo_get_signed_state(MsgInfo *msginfo, gchar **system)
 177 {
 178         struct SignedState sstate;
 179         MimeInfo *mimeinfo = procmime_scan_message(msginfo);
 180         if (!mimeinfo)
 181                 return;
 182         sstate.msginfo = msginfo;
 183         sstate.system = system;
 184         g_node_children_foreach(mimeinfo->node, G_TRAVERSE_ALL, msginfo_set_signed_flag, &sstate);
 185 }
 186
 187 /**
 188  * Check the signature of a MimeInfo. privacy_mimeinfo_is_signed
 189  * should be called before otherwise it is done by this function.
 190  * If the MimeInfo is not signed an error code will be returned.
 191  *
 192  * \return Error code indicating the result of the check,
 193  *         < 0 if an error occured
 194  */
 195 gint privacy_mimeinfo_check_signature(MimeInfo *mimeinfo)
 196 {
 197         PrivacySystem *system;
 198
 199         cm_return_val_if_fail(mimeinfo != NULL, -1);
 200
 201         if (mimeinfo->privacy == NULL)
 202                 privacy_mimeinfo_is_signed(mimeinfo);
 203
 204         if (mimeinfo->privacy == NULL)
 205                 return -1;
 206
 207         system = privacy_data_get_system(mimeinfo->privacy);
 208         if (system == NULL)
 209                 return -1;
 210
 211         if (system->check_signature == NULL)
 212                 return -1;
 213
 214         return system->check_signature(mimeinfo);
 215 }
 216
 217 SignatureStatus privacy_mimeinfo_get_sig_status(MimeInfo *mimeinfo)
 218 {
 219         PrivacySystem *system;
 220
 221         cm_return_val_if_fail(mimeinfo != NULL, -1);
 222
 223         if (mimeinfo->privacy == NULL)
 224                 privacy_mimeinfo_is_signed(mimeinfo);
 225
 226         if (mimeinfo->privacy == NULL)
 227                 return SIGNATURE_UNCHECKED;
 228
 229         system = privacy_data_get_system(mimeinfo->privacy);
 230         if (system == NULL)
 231                 return SIGNATURE_UNCHECKED;
 232         if (system->get_sig_status == NULL)
 233                 return SIGNATURE_UNCHECKED;
 234
 235         return system->get_sig_status(mimeinfo);
 236 }
 237
 238 gchar *privacy_mimeinfo_sig_info_short(MimeInfo *mimeinfo)
 239 {
 240         PrivacySystem *system;
 241
 242         cm_return_val_if_fail(mimeinfo != NULL, NULL);
 243
 244         if (mimeinfo->privacy == NULL)
 245                 privacy_mimeinfo_is_signed(mimeinfo);
 246
 247         if (mimeinfo->privacy == NULL)
 248                 return g_strdup(_("No signature found"));
 249
 250         system = privacy_data_get_system(mimeinfo->privacy);
 251         if (system == NULL)
 252                 return g_strdup(_("No signature found"));
 253         if (system->get_sig_info_short == NULL)
 254                 return g_strdup(_("No information available"));
 255
 256         return system->get_sig_info_short(mimeinfo);
 257 }
 258
 259 gchar *privacy_mimeinfo_sig_info_full(MimeInfo *mimeinfo)
 260 {
 261         PrivacySystem *system;
 262
 263         cm_return_val_if_fail(mimeinfo != NULL, NULL);
 264
 265         if (mimeinfo->privacy == NULL)
 266                 privacy_mimeinfo_is_signed(mimeinfo);
 267
 268         if (mimeinfo->privacy == NULL)
 269                 return g_strdup(_("No signature found"));
 270
 271         system = privacy_data_get_system(mimeinfo->privacy);
 272         if (system == NULL)
 273                 return g_strdup(_("No signature found"));
 274         if (system->get_sig_info_full == NULL)
 275                 return g_strdup(_("No information available"));
 276
 277         return system->get_sig_info_full(mimeinfo);
 278 }
 279
 280 gboolean privacy_mimeinfo_is_encrypted(MimeInfo *mimeinfo)
 281 {
 282         GSList *cur;
 283         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 284
 285         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 286                 PrivacySystem *system = (PrivacySystem *) cur->data;
 287
 288                 if(system->is_encrypted != NULL && system->is_encrypted(mimeinfo))
 289                         return TRUE;
 290         }
 291
 292         return FALSE;
 293 }
 294
 295 static gint decrypt(MimeInfo *mimeinfo, PrivacySystem *system)
 296 {
 297         MimeInfo *decryptedinfo, *parentinfo;
 298         gint childnumber;
 299
 300         cm_return_val_if_fail(system->decrypt != NULL, -1);
 301
 302         decryptedinfo = system->decrypt(mimeinfo);
 303         if (decryptedinfo == NULL)
 304                 return -1;
 305
 306         parentinfo = procmime_mimeinfo_parent(mimeinfo);
 307         childnumber = g_node_child_index(parentinfo->node, mimeinfo);
 308
 309         procmime_mimeinfo_free_all(mimeinfo);
 310
 311         g_node_insert(parentinfo->node, childnumber, decryptedinfo->node);
 312
 313         return 0;
 314 }
 315
 316 gint privacy_mimeinfo_decrypt(MimeInfo *mimeinfo)
 317 {
 318         GSList *cur;
 319         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 320
 321         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 322                 PrivacySystem *system = (PrivacySystem *) cur->data;
 323
 324                 if(system->is_encrypted != NULL && system->is_encrypted(mimeinfo))
 325                         return decrypt(mimeinfo, system);
 326         }
 327
 328         return -1;
 329 }
 330
 331 GSList *privacy_get_system_ids()
 332 {
 333         GSList *cur;
 334         GSList *ret = NULL;
 335
 336         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 337                 PrivacySystem *system = (PrivacySystem *) cur->data;
 338
 339                 ret = g_slist_append(ret, g_strdup(system->id));
 340         }
 341
 342         return ret;
 343 }
 344
 345 static PrivacySystem *privacy_get_system(const gchar *id)
 346 {
 347         GSList *cur;
 348
 349         cm_return_val_if_fail(id != NULL, NULL);
 350
 351         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 352                 PrivacySystem *system = (PrivacySystem *) cur->data;
 353
 354                 if(strcmp(id, system->id) == 0)
 355                         return system;
 356         }
 357
 358         return NULL;
 359 }
 360
 361 const gchar *privacy_system_get_name(const gchar *id)
 362 {
 363         PrivacySystem *system;
 364
 365         cm_return_val_if_fail(id != NULL, NULL);
 366
 367         system = privacy_get_system(id);
 368         if (system == NULL)
 369                 return NULL;
 370
 371         return system->name;
 372 }
 373
 374 gboolean privacy_system_can_sign(const gchar *id)
 375 {
 376         PrivacySystem *system;
 377
 378         cm_return_val_if_fail(id != NULL, FALSE);
 379
 380         system = privacy_get_system(id);
 381         if (system == NULL)
 382                 return FALSE;
 383
 384         return system->can_sign;
 385 }
 386
 387 gboolean privacy_system_can_encrypt(const gchar *id)
 388 {
 389         PrivacySystem *system;
 390
 391         cm_return_val_if_fail(id != NULL, FALSE);
 392
 393         system = privacy_get_system(id);
 394         if (system == NULL)
 395                 return FALSE;
 396
 397         return system->can_encrypt;
 398 }
 399
 400 gboolean privacy_sign(const gchar *id, MimeInfo *target, PrefsAccount *account, const gchar *from_addr)
 401 {
 402         PrivacySystem *system;
 403
 404         cm_return_val_if_fail(id != NULL, FALSE);
 405         cm_return_val_if_fail(target != NULL, FALSE);
 406
 407         system = privacy_get_system(id);
 408         if (system == NULL)
 409                 return FALSE;
 410         if (!system->can_sign)
 411                 return FALSE;
 412         if (system->sign == NULL)
 413                 return FALSE;
 414
 415         return system->sign(target, account, from_addr);
 416 }
 417
 418 gchar *privacy_get_encrypt_data(const gchar *id, GSList *recp_names)
 419 {
 420         PrivacySystem *system;
 421         gchar *ret = NULL;
 422         GSList *uniq_names = NULL, *cur;
 423
 424         cm_return_val_if_fail(id != NULL, NULL);
 425         cm_return_val_if_fail(recp_names != NULL, NULL);
 426
 427         system = privacy_get_system(id);
 428         if (system == NULL)
 429                 return NULL;
 430         if (!system->can_encrypt)
 431                 return NULL;
 432         if (system->get_encrypt_data == NULL)
 433                 return NULL;
 434
 435         for (cur = recp_names; cur; cur = cur->next) {
 436                 if (!g_slist_find_custom(uniq_names, cur->data, (GCompareFunc)strcmp)) {
 437                         uniq_names = g_slist_prepend(uniq_names, cur->data);
 438                 }
 439         }
 440         ret = system->get_encrypt_data(uniq_names);
 441
 442         g_slist_free(uniq_names);
 443         return ret;
 444 }
 445
 446 const gchar *privacy_get_encrypt_warning(const gchar *id)
 447 {
 448         PrivacySystem *system;
 449
 450         cm_return_val_if_fail(id != NULL, NULL);
 451
 452         system = privacy_get_system(id);
 453         if (system == NULL)
 454                 return NULL;
 455         if (!system->can_encrypt)
 456                 return NULL;
 457         if (system->get_encrypt_warning == NULL)
 458                 return NULL;
 459
 460         return system->get_encrypt_warning();
 461 }
 462
 463 void privacy_inhibit_encrypt_warning(const gchar *id, gboolean inhibit)
 464 {
 465         PrivacySystem *system;
 466
 467         cm_return_if_fail(id != NULL);
 468
 469         system = privacy_get_system(id);
 470         if (system == NULL)
 471                 return;
 472         if (!system->can_encrypt)
 473                 return;
 474         if (system->inhibit_encrypt_warning == NULL)
 475                 return;
 476
 477         system->inhibit_encrypt_warning(inhibit);
 478 }
 479
 480 gboolean privacy_encrypt(const gchar *id, MimeInfo *mimeinfo, const gchar *encdata)
 481 {
 482         PrivacySystem *system;
 483
 484         cm_return_val_if_fail(id != NULL, FALSE);
 485         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 486         if (encdata == NULL) {
 487                 privacy_set_error(_("No recipient keys defined."));
 488                 return FALSE;
 489         }
 490
 491         system = privacy_get_system(id);
 492         if (system == NULL)
 493                 return FALSE;
 494         if (!system->can_encrypt)
 495                 return FALSE;
 496         if (system->encrypt == NULL)
 497                 return FALSE;
 498
 499         return system->encrypt(mimeinfo, encdata);
 500 }