src/privacy.c

   1 /*
   2  * Claws Mail -- a GTK based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2021 the Claws Mail team and 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 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 "config.h"
  21
  22 #include <glib.h>
  23 #include <glib/gi18n.h>
  24
  25 #include "privacy.h"
  26 #include "procmime.h"
  27 #include "procmsg.h"
  28
  29 static GSList *systems = NULL;
  30 static gchar *privacy_last_error = NULL;
  31
  32 void privacy_set_error(const gchar *format, ...)
  33 {
  34         va_list args;
  35         gchar buf[BUFSIZ];
  36
  37         va_start(args, format);
  38         g_vsnprintf(buf, BUFSIZ, format, args);
  39         va_end(args);
  40         g_free(privacy_last_error);
  41         privacy_last_error = g_strdup(buf);
  42 }
  43
  44 static gchar tmp_privacy_error[BUFSIZ];
  45
  46 void privacy_reset_error(void)
  47 {
  48         g_free(privacy_last_error);
  49         privacy_last_error = NULL;
  50 }
  51
  52 gboolean privacy_peek_error(void)
  53 {
  54         return (privacy_last_error != NULL);
  55 }
  56
  57 const gchar *privacy_get_error (void)
  58 {
  59         if (privacy_last_error) {
  60                 strncpy2(tmp_privacy_error, privacy_last_error, BUFSIZ-1);
  61                 privacy_reset_error();
  62                 return tmp_privacy_error;
  63         } else {
  64                 return _("Unknown error");
  65         }
  66 }
  67
  68 static PrivacySystem *privacy_data_get_system(PrivacyData *data)
  69 {
  70         /* Make sure the cached system is still registered */
  71         if (data->system && g_slist_find(systems, data->system))
  72                 return data->system;
  73         else
  74                 return NULL;
  75 }
  76 /**
  77  * Register a new Privacy System
  78  *
  79  * \param system The Privacy System that should be registered
  80  */
  81 void privacy_register_system(PrivacySystem *system)
  82 {
  83         systems = g_slist_append(systems, system);
  84 }
  85
  86 /**
  87  * Unregister a new Privacy System. The system must not be in
  88  * use anymore when it is unregistered.
  89  *
  90  * \param system The Privacy System that should be unregistered
  91  */
  92 void privacy_unregister_system(PrivacySystem *system)
  93 {
  94         systems = g_slist_remove(systems, system);
  95 }
  96
  97 /**
  98  * Free a PrivacyData of a PrivacySystem
  99  *
 100  * \param privacydata The data to free
 101  */
 102 void privacy_free_privacydata(PrivacyData *privacydata)
 103 {
 104         PrivacySystem *system = NULL;
 105
 106         cm_return_if_fail(privacydata != NULL);
 107
 108         system = privacy_data_get_system(privacydata);
 109         if (!system)
 110                 return;
 111         system->free_privacydata(privacydata);
 112 }
 113
 114 void privacy_free_signature_data(SignatureData *sig_data)
 115 {
 116         cm_return_if_fail(sig_data != NULL);
 117
 118         g_free(sig_data->info_short);
 119         g_free(sig_data->info_full);
 120         g_free(sig_data);
 121 }
 122
 123 void privacy_free_sig_check_task_result(gpointer data)
 124 {
 125         SigCheckTaskResult *result = (SigCheckTaskResult *)data;
 126
 127         privacy_free_signature_data(result->sig_data);
 128         if (result->newinfo)
 129                 procmime_mimeinfo_free_all(&result->newinfo);
 130         g_free(result);
 131 }
 132
 133 /**
 134  * Check if a MimeInfo is signed with one of the available
 135  * privacy system. If a privacydata is set in the MimeInfo
 136  * it will directory return the return value by the system
 137  * set in the privacy data or check all available privacy
 138  * systems otherwise.
 139  *
 140  * \return True if the MimeInfo has a signature
 141  */
 142 gboolean privacy_mimeinfo_is_signed(MimeInfo *mimeinfo)
 143 {
 144         GSList *cur;
 145         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 146
 147         if (mimeinfo->privacy != NULL) {
 148                 PrivacySystem *system =
 149                         privacy_data_get_system(mimeinfo->privacy);
 150
 151                 if (system == NULL) {
 152                         mimeinfo->privacy = NULL;
 153                         goto try_others;
 154                 }
 155
 156                 if (system->is_signed != NULL)
 157                         return system->is_signed(mimeinfo);
 158                 else
 159                         return FALSE;
 160         }
 161 try_others:
 162         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 163                 PrivacySystem *system = (PrivacySystem *) cur->data;
 164
 165                 if(system->is_signed != NULL && system->is_signed(mimeinfo))
 166                         return TRUE;
 167         }
 168
 169         return FALSE;
 170 }
 171
 172 struct SignedState {
 173         MsgInfo *msginfo;
 174         gchar **system;
 175 };
 176
 177 static void msginfo_set_signed_flag(GNode *node, gpointer data)
 178 {
 179         struct SignedState *sstate = (struct SignedState *)data;
 180         MsgInfo *msginfo = sstate->msginfo;
 181         MimeInfo *mimeinfo = node->data;
 182
 183         if (privacy_mimeinfo_is_signed(mimeinfo)) {
 184                 procmsg_msginfo_set_flags(msginfo, 0, MSG_SIGNED);
 185                 if (sstate->system && !*(sstate->system) && mimeinfo->privacy)
 186                         *(sstate->system) = g_strdup(mimeinfo->privacy->system->id);
 187         }
 188         if (privacy_mimeinfo_is_encrypted(mimeinfo)) {
 189                 procmsg_msginfo_set_flags(msginfo, 0, MSG_ENCRYPTED);
 190                 if (sstate->system && !*(sstate->system) && mimeinfo->privacy)
 191                         *(sstate->system) = g_strdup(mimeinfo->privacy->system->id);
 192         } else {
 193                 /* searching inside encrypted parts doesn't really make sense */
 194                 g_node_children_foreach(mimeinfo->node, G_TRAVERSE_ALL, msginfo_set_signed_flag, sstate);
 195         }
 196 }
 197
 198 void privacy_msginfo_get_signed_state(MsgInfo *msginfo, gchar **system)
 199 {
 200         struct SignedState sstate;
 201         MimeInfo *mimeinfo = procmime_scan_message(msginfo);
 202         if (!mimeinfo)
 203                 return;
 204         sstate.msginfo = msginfo;
 205         sstate.system = system;
 206         g_node_children_foreach(mimeinfo->node, G_TRAVERSE_ALL, msginfo_set_signed_flag, &sstate);
 207 }
 208
 209 /**
 210  * Check the signature of a MimeInfo. privacy_mimeinfo_is_signed
 211  * should be called before otherwise it is done by this function.
 212  * If the MimeInfo is not signed an error code will be returned.
 213  *
 214  * \return Error code indicating the result of the check,
 215  *         < 0 if an error occurred
 216  */
 217 gint privacy_mimeinfo_check_signature(MimeInfo *mimeinfo,
 218         GCancellable *cancellable,
 219         GAsyncReadyCallback callback,
 220         gpointer user_data)
 221 {
 222         PrivacySystem *system;
 223
 224         if (mimeinfo == NULL)
 225                 g_error("siginfo was NULL");
 226
 227         if (mimeinfo->privacy == NULL) {
 228                 g_warning("mimeinfo->privacy was NULL");
 229
 230                 privacy_mimeinfo_is_signed(mimeinfo);
 231                 if (mimeinfo->privacy == NULL) {
 232                         g_error("failed to set up PrivacyData");
 233                 }
 234         }
 235
 236         system = privacy_data_get_system(mimeinfo->privacy);
 237         if (system == NULL)
 238                 g_error("failed to get privacy system");
 239         else if (system->check_signature == NULL)
 240                 g_error("didn't find check_signature function");
 241
 242         return system->check_signature(mimeinfo, cancellable, callback, user_data);
 243 }
 244
 245 SignatureStatus privacy_mimeinfo_get_sig_status(MimeInfo *mimeinfo)
 246 {
 247         PrivacySystem *system;
 248
 249         cm_return_val_if_fail(mimeinfo != NULL, -1);
 250
 251         if (mimeinfo->privacy == NULL) {
 252                 privacy_mimeinfo_is_signed(mimeinfo);
 253
 254                 if (mimeinfo->privacy == NULL)
 255                         return SIGNATURE_UNCHECKED;
 256         }
 257
 258         system = privacy_data_get_system(mimeinfo->privacy);
 259         if (system == NULL)
 260                 return SIGNATURE_UNCHECKED;
 261
 262         if (mimeinfo->sig_data == NULL)
 263                 return SIGNATURE_UNCHECKED;
 264         else
 265                 return mimeinfo->sig_data->status;
 266 }
 267
 268 gchar *privacy_mimeinfo_get_sig_info(MimeInfo *mimeinfo, gboolean full)
 269 {
 270         PrivacySystem *system;
 271         gchar *info;
 272
 273         cm_return_val_if_fail(mimeinfo != NULL, NULL);
 274
 275         if (mimeinfo->privacy == NULL) {
 276                 privacy_mimeinfo_is_signed(mimeinfo);
 277
 278                 if (mimeinfo->privacy == NULL)
 279                         return _("No signature found");
 280         }
 281
 282         system = privacy_data_get_system(mimeinfo->privacy);
 283         if (system == NULL)
 284                 return _("No signature found");
 285
 286         if (mimeinfo->sig_data == NULL)
 287                 return _("No information available");
 288
 289         info = full ? mimeinfo->sig_data->info_full : mimeinfo->sig_data->info_short;
 290         if (info == NULL)
 291                 return _("No information available");
 292
 293         return info;
 294 }
 295
 296 gboolean privacy_mimeinfo_is_encrypted(MimeInfo *mimeinfo)
 297 {
 298         GSList *cur;
 299         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 300
 301         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 302                 PrivacySystem *system = (PrivacySystem *) cur->data;
 303
 304                 if(system->is_encrypted != NULL && system->is_encrypted(mimeinfo))
 305                         return TRUE;
 306         }
 307
 308         return FALSE;
 309 }
 310
 311 static gint decrypt(MimeInfo *mimeinfo, PrivacySystem *system)
 312 {
 313         MimeInfo *decryptedinfo, *parentinfo;
 314         gint childnumber;
 315
 316         cm_return_val_if_fail(system->decrypt != NULL, -1);
 317
 318         decryptedinfo = system->decrypt(mimeinfo);
 319         if (decryptedinfo == NULL)
 320                 return -1;
 321
 322         parentinfo = procmime_mimeinfo_parent(mimeinfo);
 323         childnumber = g_node_child_index(parentinfo->node, mimeinfo);
 324
 325         procmime_mimeinfo_free_all(&mimeinfo);
 326
 327         g_node_insert(parentinfo->node, childnumber, decryptedinfo->node);
 328
 329         return 0;
 330 }
 331
 332 gint privacy_mimeinfo_decrypt(MimeInfo *mimeinfo)
 333 {
 334         GSList *cur;
 335         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 336
 337         procmime_decode_content(mimeinfo);
 338
 339         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 340                 PrivacySystem *system = (PrivacySystem *) cur->data;
 341
 342                 if(system->is_encrypted != NULL && system->is_encrypted(mimeinfo))
 343                         return decrypt(mimeinfo, system);
 344         }
 345
 346         return -1;
 347 }
 348
 349 GSList *privacy_get_system_ids()
 350 {
 351         GSList *cur;
 352         GSList *ret = NULL;
 353
 354         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 355                 PrivacySystem *system = (PrivacySystem *) cur->data;
 356
 357                 ret = g_slist_append(ret, g_strdup(system->id));
 358         }
 359
 360         return ret;
 361 }
 362
 363 static PrivacySystem *privacy_get_system(const gchar *id)
 364 {
 365         GSList *cur;
 366
 367         cm_return_val_if_fail(id != NULL, NULL);
 368
 369         for(cur = systems; cur != NULL; cur = g_slist_next(cur)) {
 370                 PrivacySystem *system = (PrivacySystem *) cur->data;
 371
 372                 if(strcmp(id, system->id) == 0)
 373                         return system;
 374         }
 375
 376         return NULL;
 377 }
 378
 379 const gchar *privacy_system_get_name(const gchar *id)
 380 {
 381         PrivacySystem *system;
 382
 383         cm_return_val_if_fail(id != NULL, NULL);
 384
 385         system = privacy_get_system(id);
 386         if (system == NULL)
 387                 return NULL;
 388
 389         return system->name;
 390 }
 391
 392 gboolean privacy_system_can_sign(const gchar *id)
 393 {
 394         PrivacySystem *system;
 395
 396         cm_return_val_if_fail(id != NULL, FALSE);
 397
 398         system = privacy_get_system(id);
 399         if (system == NULL)
 400                 return FALSE;
 401
 402         return system->can_sign;
 403 }
 404
 405 gboolean privacy_system_can_encrypt(const gchar *id)
 406 {
 407         PrivacySystem *system;
 408
 409         cm_return_val_if_fail(id != NULL, FALSE);
 410
 411         system = privacy_get_system(id);
 412         if (system == NULL)
 413                 return FALSE;
 414
 415         return system->can_encrypt;
 416 }
 417
 418 gboolean privacy_sign(const gchar *id, MimeInfo *target, PrefsAccount *account, const gchar *from_addr)
 419 {
 420         PrivacySystem *system;
 421
 422         cm_return_val_if_fail(id != NULL, FALSE);
 423         cm_return_val_if_fail(target != NULL, FALSE);
 424
 425         system = privacy_get_system(id);
 426         if (system == NULL)
 427                 return FALSE;
 428         if (!system->can_sign)
 429                 return FALSE;
 430         if (system->sign == NULL)
 431                 return FALSE;
 432
 433         return system->sign(target, account, from_addr);
 434 }
 435
 436 gchar *privacy_get_encrypt_data(const gchar *id, GSList *recp_names)
 437 {
 438         PrivacySystem *system;
 439         gchar *ret = NULL;
 440         GSList *uniq_names = NULL, *cur;
 441
 442         cm_return_val_if_fail(id != NULL, NULL);
 443         cm_return_val_if_fail(recp_names != NULL, NULL);
 444
 445         system = privacy_get_system(id);
 446         if (system == NULL)
 447                 return NULL;
 448         if (!system->can_encrypt)
 449                 return NULL;
 450         if (system->get_encrypt_data == NULL)
 451                 return NULL;
 452
 453         for (cur = recp_names; cur; cur = cur->next) {
 454                 if (!g_slist_find_custom(uniq_names, cur->data, (GCompareFunc)strcmp)) {
 455                         uniq_names = g_slist_prepend(uniq_names, cur->data);
 456                 }
 457         }
 458         ret = system->get_encrypt_data(uniq_names);
 459
 460         g_slist_free(uniq_names);
 461         return ret;
 462 }
 463
 464 const gchar *privacy_get_encrypt_warning(const gchar *id)
 465 {
 466         PrivacySystem *system;
 467
 468         cm_return_val_if_fail(id != NULL, NULL);
 469
 470         system = privacy_get_system(id);
 471         if (system == NULL)
 472                 return NULL;
 473         if (!system->can_encrypt)
 474                 return NULL;
 475         if (system->get_encrypt_warning == NULL)
 476                 return NULL;
 477
 478         return system->get_encrypt_warning();
 479 }
 480
 481 void privacy_inhibit_encrypt_warning(const gchar *id, gboolean inhibit)
 482 {
 483         PrivacySystem *system;
 484
 485         cm_return_if_fail(id != NULL);
 486
 487         system = privacy_get_system(id);
 488         if (system == NULL)
 489                 return;
 490         if (!system->can_encrypt)
 491                 return;
 492         if (system->inhibit_encrypt_warning == NULL)
 493                 return;
 494
 495         system->inhibit_encrypt_warning(inhibit);
 496 }
 497
 498 gboolean privacy_encrypt(const gchar *id, MimeInfo *mimeinfo, const gchar *encdata)
 499 {
 500         PrivacySystem *system;
 501
 502         cm_return_val_if_fail(id != NULL, FALSE);
 503         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 504         if (encdata == NULL) {
 505                 privacy_set_error(_("No recipient keys defined."));
 506                 return FALSE;
 507         }
 508
 509         system = privacy_get_system(id);
 510         if (system == NULL)
 511                 return FALSE;
 512         if (!system->can_encrypt)
 513                 return FALSE;
 514         if (system->encrypt == NULL)
 515                 return FALSE;
 516
 517         return system->encrypt(mimeinfo, encdata);
 518 }
 519
 520 gboolean privacy_auto_check_signatures(MimeInfo *mimeinfo)
 521 {
 522         PrivacySystem *system;
 523
 524         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
 525
 526         if (mimeinfo->privacy == NULL)
 527                 privacy_mimeinfo_is_signed(mimeinfo);
 528
 529         if (mimeinfo->privacy == NULL)
 530                 return FALSE;
 531
 532         system = privacy_data_get_system(mimeinfo->privacy);
 533         if (system == NULL)
 534                 return FALSE;
 535         if (system->auto_check_signatures == NULL)
 536                 return FALSE;
 537
 538         return system->auto_check_signatures();
 539 }