src/plugins/pgpmime/pgpmime.c

   1 /*
   2  * Claws Mail -- a GTK+ based, lightweight, and fast e-mail client
   3  * Copyright (C) 1999-2011 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 #ifdef HAVE_CONFIG_H
  21 #  include "config.h"
  22 #endif
  23
  24 #ifdef USE_GPGME
  25
  26 #include "defs.h"
  27 #include <glib.h>
  28 #include <glib/gi18n.h>
  29 #include <gpgme.h>
  30 #include <ctype.h>
  31 #include <errno.h>
  32
  33 #include "utils.h"
  34 #include "privacy.h"
  35 #include "procmime.h"
  36 #include "plugin.h"
  37
  38 #include "pgpmime.h"
  39 #include <plugins/pgpcore/sgpgme.h>
  40 #include <plugins/pgpcore/prefs_gpg.h>
  41 #include <plugins/pgpcore/passphrase.h>
  42
  43 #include "prefs_common.h"
  44
  45 typedef struct _PrivacyDataPGP PrivacyDataPGP;
  46
  47 struct _PrivacyDataPGP
  48 {
  49         PrivacyData     data;
  50
  51         gboolean        done_sigtest;
  52         gboolean        is_signed;
  53         gpgme_verify_result_t   sigstatus;
  54         gpgme_ctx_t     ctx;
  55 };
  56
  57 static PrivacySystem pgpmime_system;
  58
  59 static gint pgpmime_check_signature(MimeInfo *mimeinfo);
  60
  61 static PrivacyDataPGP *pgpmime_new_privacydata()
  62 {
  63         PrivacyDataPGP *data;
  64         gpgme_error_t err;
  65
  66         data = g_new0(PrivacyDataPGP, 1);
  67         data->data.system = &pgpmime_system;
  68         data->done_sigtest = FALSE;
  69         data->is_signed = FALSE;
  70         data->sigstatus = NULL;
  71         if ((err = gpgme_new(&data->ctx)) != GPG_ERR_NO_ERROR) {
  72                 g_warning(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
  73                 return NULL;
  74         }
  75
  76         return data;
  77 }
  78
  79 static void pgpmime_free_privacydata(PrivacyData *_data)
  80 {
  81         PrivacyDataPGP *data = (PrivacyDataPGP *) _data;
  82         gpgme_release(data->ctx);
  83         g_free(data);
  84 }
  85
  86 static gboolean pgpmime_is_signed(MimeInfo *mimeinfo)
  87 {
  88         MimeInfo *parent;
  89         MimeInfo *signature;
  90         const gchar *protocol;
  91         PrivacyDataPGP *data = NULL;
  92
  93         cm_return_val_if_fail(mimeinfo != NULL, FALSE);
  94         if (mimeinfo->privacy != NULL) {
  95                 data = (PrivacyDataPGP *) mimeinfo->privacy;
  96                 if (data->done_sigtest)
  97                         return data->is_signed;
  98         }
  99
 100         /* check parent */
 101         parent = procmime_mimeinfo_parent(mimeinfo);
 102         if (parent == NULL)
 103                 return FALSE;
 104         if ((parent->type != MIMETYPE_MULTIPART) ||
 105             g_ascii_strcasecmp(parent->subtype, "signed"))
 106                 return FALSE;
 107         protocol = procmime_mimeinfo_get_parameter(parent, "protocol");
 108         if ((protocol == NULL) ||
 109             (g_ascii_strcasecmp(protocol, "application/pgp-signature")))
 110                 return FALSE;
 111
 112         /* check if mimeinfo is the first child */
 113         if (parent->node->children->data != mimeinfo)
 114                 return FALSE;
 115
 116         /* check signature */
 117         signature = parent->node->children->next != NULL ?
 118             (MimeInfo *) parent->node->children->next->data : NULL;
 119         if (signature == NULL)
 120                 return FALSE;
 121         if ((signature->type != MIMETYPE_APPLICATION) ||
 122             (g_ascii_strcasecmp(signature->subtype, "pgp-signature")))
 123                 return FALSE;
 124
 125         if (data == NULL) {
 126                 data = pgpmime_new_privacydata();
 127                 mimeinfo->privacy = (PrivacyData *) data;
 128         }
 129
 130         data->done_sigtest = TRUE;
 131         data->is_signed = TRUE;
 132
 133         return TRUE;
 134 }
 135
 136 static gchar *get_canonical_content(FILE *fp, const gchar *boundary)
 137 {
 138         gchar *ret;
 139         GString *textbuffer;
 140         guint boundary_len;
 141         gchar buf[BUFFSIZE];
 142
 143         boundary_len = strlen(boundary);
 144         while (fgets(buf, sizeof(buf), fp) != NULL)
 145                 if (IS_BOUNDARY(buf, boundary, boundary_len))
 146                         break;
 147
 148         textbuffer = g_string_new("");
 149         while (fgets(buf, sizeof(buf), fp) != NULL) {
 150                 gchar *buf2;
 151
 152                 if (IS_BOUNDARY(buf, boundary, boundary_len))
 153                         break;
 154
 155                 buf2 = canonicalize_str(buf);
 156                 g_string_append(textbuffer, buf2);
 157                 g_free(buf2);
 158         }
 159         g_string_truncate(textbuffer, textbuffer->len - 2);
 160
 161         ret = textbuffer->str;
 162         g_string_free(textbuffer, FALSE);
 163
 164         return ret;
 165 }
 166
 167 static gint pgpmime_check_signature(MimeInfo *mimeinfo)
 168 {
 169         PrivacyDataPGP *data;
 170         MimeInfo *parent, *signature;
 171         FILE *fp;
 172         gchar *boundary;
 173         gchar *textstr;
 174         gpgme_data_t sigdata = NULL, textdata = NULL;
 175         gpgme_error_t err;
 176         cm_return_val_if_fail(mimeinfo != NULL, -1);
 177         cm_return_val_if_fail(mimeinfo->privacy != NULL, -1);
 178         data = (PrivacyDataPGP *) mimeinfo->privacy;
 179         if ((err = gpgme_new(&data->ctx)) != GPG_ERR_NO_ERROR) {
 180                 debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 181                 privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 182                 return 0;
 183         }
 184
 185
 186         debug_print("Checking PGP/MIME signature\n");
 187
 188         err = gpgme_set_protocol(data->ctx, GPGME_PROTOCOL_OpenPGP);
 189
 190         if (err) {
 191                 debug_print ("gpgme_set_protocol failed: %s\n",
 192                    gpgme_strerror (err));
 193         }
 194         parent = procmime_mimeinfo_parent(mimeinfo);
 195
 196         fp = g_fopen(parent->data.filename, "rb");
 197         cm_return_val_if_fail(fp != NULL, SIGNATURE_INVALID);
 198
 199         boundary = g_hash_table_lookup(parent->typeparameters, "boundary");
 200         if (!boundary) {
 201                 privacy_set_error(_("Signature boundary not found."));
 202                 fclose(fp);
 203                 return 0;
 204         }
 205         textstr = get_canonical_content(fp, boundary);
 206
 207         err = gpgme_data_new_from_mem(&textdata, textstr, (size_t)strlen(textstr), 0);
 208         if (err) {
 209                 debug_print ("gpgme_data_new_from_mem failed: %s\n",
 210                    gpgme_strerror (err));
 211         }
 212         signature = (MimeInfo *) mimeinfo->node->next->data;
 213         sigdata = sgpgme_data_from_mimeinfo(signature);
 214
 215         err = 0;
 216         if (signature->encoding_type == ENC_BASE64) {
 217                 err = gpgme_data_set_encoding (sigdata, GPGME_DATA_ENCODING_BASE64);
 218         }
 219
 220         if (err) {
 221                 debug_print ("gpgme_data_set_encoding failed: %s\n",
 222                         gpgme_strerror (err));
 223         }
 224
 225         data->sigstatus =
 226                 sgpgme_verify_signature (data->ctx, sigdata, textdata, NULL);
 227
 228         gpgme_data_release(sigdata);
 229         gpgme_data_release(textdata);
 230         g_free(textstr);
 231         fclose(fp);
 232
 233         return 0;
 234 }
 235
 236 static SignatureStatus pgpmime_get_sig_status(MimeInfo *mimeinfo)
 237 {
 238         PrivacyDataPGP *data = (PrivacyDataPGP *) mimeinfo->privacy;
 239
 240         cm_return_val_if_fail(data != NULL, SIGNATURE_INVALID);
 241
 242         if (data->sigstatus == NULL &&
 243             prefs_gpg_get_config()->auto_check_signatures)
 244                 pgpmime_check_signature(mimeinfo);
 245
 246         return sgpgme_sigstat_gpgme_to_privacy(data->ctx, data->sigstatus);
 247 }
 248
 249 static gchar *pgpmime_get_sig_info_short(MimeInfo *mimeinfo)
 250 {
 251         PrivacyDataPGP *data = (PrivacyDataPGP *) mimeinfo->privacy;
 252
 253         cm_return_val_if_fail(data != NULL, g_strdup("Error"));
 254
 255         if (data->sigstatus == NULL &&
 256             prefs_gpg_get_config()->auto_check_signatures)
 257                 pgpmime_check_signature(mimeinfo);
 258
 259         return sgpgme_sigstat_info_short(data->ctx, data->sigstatus);
 260 }
 261
 262 static gchar *pgpmime_get_sig_info_full(MimeInfo *mimeinfo)
 263 {
 264         PrivacyDataPGP *data = (PrivacyDataPGP *) mimeinfo->privacy;
 265
 266         cm_return_val_if_fail(data != NULL, g_strdup("Error"));
 267
 268         if (data->sigstatus == NULL &&
 269             prefs_gpg_get_config()->auto_check_signatures)
 270                 pgpmime_check_signature(mimeinfo);
 271
 272         return sgpgme_sigstat_info_full(data->ctx, data->sigstatus);
 273 }
 274
 275 static gboolean pgpmime_is_encrypted(MimeInfo *mimeinfo)
 276 {
 277         MimeInfo *tmpinfo;
 278         const gchar *tmpstr;
 279
 280         if (mimeinfo->type != MIMETYPE_MULTIPART)
 281                 return FALSE;
 282         if (g_ascii_strcasecmp(mimeinfo->subtype, "encrypted"))
 283                 return FALSE;
 284         tmpstr = procmime_mimeinfo_get_parameter(mimeinfo, "protocol");
 285         if ((tmpstr == NULL) || g_ascii_strcasecmp(tmpstr, "application/pgp-encrypted"))
 286                 return FALSE;
 287         if (g_node_n_children(mimeinfo->node) != 2)
 288                 return FALSE;
 289
 290         tmpinfo = (MimeInfo *) g_node_nth_child(mimeinfo->node, 0)->data;
 291         if (tmpinfo->type != MIMETYPE_APPLICATION)
 292                 return FALSE;
 293         if (g_ascii_strcasecmp(tmpinfo->subtype, "pgp-encrypted"))
 294                 return FALSE;
 295
 296         tmpinfo = (MimeInfo *) g_node_nth_child(mimeinfo->node, 1)->data;
 297         if (tmpinfo->type != MIMETYPE_APPLICATION)
 298                 return FALSE;
 299         if (g_ascii_strcasecmp(tmpinfo->subtype, "octet-stream"))
 300                 return FALSE;
 301
 302         return TRUE;
 303 }
 304
 305 static MimeInfo *pgpmime_decrypt(MimeInfo *mimeinfo)
 306 {
 307         MimeInfo *encinfo, *decinfo, *parseinfo;
 308         gpgme_data_t cipher = NULL, plain = NULL;
 309         static gint id = 0;
 310         FILE *dstfp;
 311         gchar *fname;
 312         gpgme_verify_result_t sigstat = NULL;
 313         PrivacyDataPGP *data = NULL;
 314         gpgme_ctx_t ctx;
 315         gchar *chars;
 316         size_t len;
 317         gpgme_error_t err;
 318
 319         if ((err = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR) {
 320                 debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 321                 privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 322                 return NULL;
 323         }
 324
 325         cm_return_val_if_fail(pgpmime_is_encrypted(mimeinfo), NULL);
 326
 327         encinfo = (MimeInfo *) g_node_nth_child(mimeinfo->node, 1)->data;
 328
 329         cipher = sgpgme_data_from_mimeinfo(encinfo);
 330         plain = sgpgme_decrypt_verify(cipher, &sigstat, ctx);
 331
 332         gpgme_data_release(cipher);
 333         if (plain == NULL) {
 334                 debug_print("plain is null!\n");
 335                 gpgme_release(ctx);
 336                 return NULL;
 337         }
 338
 339         fname = g_strdup_printf("%s%cplaintext.%08x",
 340                 get_mime_tmp_dir(), G_DIR_SEPARATOR, ++id);
 341
 342         if ((dstfp = g_fopen(fname, "wb")) == NULL) {
 343                 FILE_OP_ERROR(fname, "fopen");
 344                 privacy_set_error(_("Couldn't open decrypted file %s"), fname);
 345                 g_free(fname);
 346                 gpgme_data_release(plain);
 347                 gpgme_release(ctx);
 348                 debug_print("can't open!\n");
 349                 return NULL;
 350         }
 351
 352         if (fprintf(dstfp, "MIME-Version: 1.0\n") < 0) {
 353                 FILE_OP_ERROR(fname, "fprintf");
 354                 fclose(dstfp);
 355                 privacy_set_error(_("Couldn't write to decrypted file %s"), fname);
 356                 g_free(fname);
 357                 gpgme_data_release(plain);
 358                 gpgme_release(ctx);
 359                 debug_print("can't open!\n");
 360                 return NULL;
 361         }
 362
 363         chars = sgpgme_data_release_and_get_mem(plain, &len);
 364         if (len > 0) {
 365                 if (fwrite(chars, 1, len, dstfp) < len) {
 366                         FILE_OP_ERROR(fname, "fwrite");
 367                         fclose(dstfp);
 368                         privacy_set_error(_("Couldn't write to decrypted file %s"), fname);
 369                         g_free(fname);
 370                         gpgme_data_release(plain);
 371                         gpgme_release(ctx);
 372                         debug_print("can't open!\n");
 373                         return NULL;
 374                 }
 375         }
 376         if (fclose(dstfp) == EOF) {
 377                 FILE_OP_ERROR(fname, "fclose");
 378                 privacy_set_error(_("Couldn't close decrypted file %s"), fname);
 379                 g_free(fname);
 380                 gpgme_data_release(plain);
 381                 gpgme_release(ctx);
 382                 debug_print("can't open!\n");
 383                 return NULL;
 384         }
 385
 386         parseinfo = procmime_scan_file(fname);
 387         g_free(fname);
 388         if (parseinfo == NULL) {
 389                 gpgme_release(ctx);
 390                 privacy_set_error(_("Couldn't parse decrypted file."));
 391                 return NULL;
 392         }
 393         decinfo = g_node_first_child(parseinfo->node) != NULL ?
 394                 g_node_first_child(parseinfo->node)->data : NULL;
 395         if (decinfo == NULL) {
 396                 privacy_set_error(_("Couldn't parse decrypted file parts."));
 397                 gpgme_release(ctx);
 398                 return NULL;
 399         }
 400
 401         g_node_unlink(decinfo->node);
 402         procmime_mimeinfo_free_all(parseinfo);
 403
 404         decinfo->tmp = TRUE;
 405
 406         if (sigstat != NULL && sigstat->signatures != NULL) {
 407                 if (decinfo->privacy != NULL) {
 408                         data = (PrivacyDataPGP *) decinfo->privacy;
 409                 } else {
 410                         data = pgpmime_new_privacydata();
 411                         decinfo->privacy = (PrivacyData *) data;
 412                 }
 413                 data->done_sigtest = TRUE;
 414                 data->is_signed = TRUE;
 415                 data->sigstatus = sigstat;
 416                 if (data->ctx)
 417                         gpgme_release(data->ctx);
 418                 data->ctx = ctx;
 419         } else
 420                 gpgme_release(ctx);
 421
 422         return decinfo;
 423 }
 424
 425 gboolean pgpmime_sign(MimeInfo *mimeinfo, PrefsAccount *account, const gchar *from_addr)
 426 {
 427         MimeInfo *msgcontent, *sigmultipart, *newinfo;
 428         gchar *textstr, *micalg = NULL;
 429         FILE *fp;
 430         gchar *boundary = NULL;
 431         gchar *sigcontent;
 432         gpgme_ctx_t ctx;
 433         gpgme_data_t gpgtext, gpgsig;
 434         gpgme_error_t err;
 435         size_t len;
 436         struct passphrase_cb_info_s info;
 437         gpgme_sign_result_t result = NULL;
 438         gchar *test_msg;
 439
 440         fp = my_tmpfile();
 441         if (fp == NULL) {
 442                 privacy_set_error(_("Couldn't create temporary file: %s"), strerror(errno));
 443                 return FALSE;
 444         }
 445         procmime_write_mimeinfo(mimeinfo, fp);
 446         rewind(fp);
 447
 448         /* read temporary file into memory */
 449         test_msg = file_read_stream_to_str(fp);
 450         fclose(fp);
 451
 452         memset (&info, 0, sizeof info);
 453
 454         /* remove content node from message */
 455         msgcontent = (MimeInfo *) mimeinfo->node->children->data;
 456         g_node_unlink(msgcontent->node);
 457
 458         /* create temporary multipart for content */
 459         sigmultipart = procmime_mimeinfo_new();
 460         sigmultipart->type = MIMETYPE_MULTIPART;
 461         sigmultipart->subtype = g_strdup("signed");
 462
 463         do {
 464                 g_free(boundary);
 465                 boundary = generate_mime_boundary("Sig");
 466         } while (strstr(test_msg, boundary) != NULL);
 467
 468         g_free(test_msg);
 469
 470         g_hash_table_insert(sigmultipart->typeparameters, g_strdup("boundary"),
 471                             g_strdup(boundary));
 472         g_hash_table_insert(sigmultipart->typeparameters, g_strdup("protocol"),
 473                             g_strdup("application/pgp-signature"));
 474         g_node_append(sigmultipart->node, msgcontent->node);
 475         g_node_append(mimeinfo->node, sigmultipart->node);
 476
 477         /* write message content to temporary file */
 478         fp = my_tmpfile();
 479         if (fp == NULL) {
 480                 perror("my_tmpfile");
 481                 privacy_set_error(_("Couldn't create temporary file: %s"), strerror(errno));
 482                 return FALSE;
 483         }
 484         procmime_write_mimeinfo(sigmultipart, fp);
 485         rewind(fp);
 486
 487         /* read temporary file into memory */
 488         textstr = get_canonical_content(fp, boundary);
 489
 490         fclose(fp);
 491
 492         gpgme_data_new_from_mem(&gpgtext, textstr, (size_t)strlen(textstr), 0);
 493         gpgme_data_new(&gpgsig);
 494         if ((err = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR) {
 495                 debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 496                 privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 497                 return FALSE;
 498         }
 499         gpgme_set_textmode(ctx, 1);
 500         gpgme_set_armor(ctx, 1);
 501         gpgme_signers_clear (ctx);
 502
 503         if (!sgpgme_setup_signers(ctx, account, from_addr)) {
 504                 gpgme_release(ctx);
 505                 return FALSE;
 506         }
 507
 508         prefs_gpg_enable_agent(prefs_gpg_get_config()->use_gpg_agent);
 509         if (getenv("GPG_AGENT_INFO") && prefs_gpg_get_config()->use_gpg_agent) {
 510                 debug_print("GPG_AGENT_INFO environment defined, running without passphrase callback\n");
 511         } else {
 512                 info.c = ctx;
 513                 gpgme_set_passphrase_cb (ctx, gpgmegtk_passphrase_cb, &info);
 514         }
 515
 516         err = gpgme_op_sign(ctx, gpgtext, gpgsig, GPGME_SIG_MODE_DETACH);
 517         if (err != GPG_ERR_NO_ERROR) {
 518                 if (err == GPG_ERR_CANCELED) {
 519                         /* ignore cancelled signing */
 520                         privacy_reset_error();
 521                         debug_print("gpgme_op_sign cancelled\n");
 522                 } else {
 523                         privacy_set_error(_("Data signing failed, %s"), gpgme_strerror(err));
 524                         debug_print("gpgme_op_sign error : %x\n", err);
 525                 }
 526                 gpgme_release(ctx);
 527                 return FALSE;
 528         }
 529         result = gpgme_op_sign_result(ctx);
 530         if (result && result->signatures) {
 531                 gpgme_new_signature_t sig = result->signatures;
 532                 if (gpgme_get_protocol(ctx) == GPGME_PROTOCOL_OpenPGP) {
 533                         micalg = g_strdup_printf("PGP-%s", gpgme_hash_algo_name(
 534                                 result->signatures->hash_algo));
 535                 } else {
 536                         micalg = g_strdup(gpgme_hash_algo_name(
 537                                 result->signatures->hash_algo));
 538                 }
 539                 while (sig) {
 540                         debug_print("valid signature: %s\n", sig->fpr);
 541                         sig = sig->next;
 542                 }
 543         } else if (result && result->invalid_signers) {
 544                 gpgme_invalid_key_t invalid = result->invalid_signers;
 545                 while (invalid) {
 546                         g_warning("invalid signer: %s (%s)", invalid->fpr,
 547                                 gpgme_strerror(invalid->reason));
 548                         privacy_set_error(_("Data signing failed due to invalid signer: %s"),
 549                                 gpgme_strerror(invalid->reason));
 550                         invalid = invalid->next;
 551                 }
 552                 gpgme_release(ctx);
 553                 return FALSE;
 554         } else {
 555                 /* can't get result (maybe no signing key?) */
 556                 debug_print("gpgme_op_sign_result error\n");
 557                 privacy_set_error(_("Data signing failed, no results."));
 558                 gpgme_release(ctx);
 559                 return FALSE;
 560         }
 561
 562         sigcontent = sgpgme_data_release_and_get_mem(gpgsig, &len);
 563         gpgme_data_release(gpgtext);
 564         g_free(textstr);
 565
 566         if (sigcontent == NULL || len <= 0) {
 567                 g_warning("sgpgme_data_release_and_get_mem failed");
 568                 privacy_set_error(_("Data signing failed, no contents."));
 569                 g_free(micalg);
 570                 return FALSE;
 571         }
 572
 573         /* add signature */
 574         g_hash_table_insert(sigmultipart->typeparameters, g_strdup("micalg"),
 575                             micalg);
 576
 577         newinfo = procmime_mimeinfo_new();
 578         newinfo->type = MIMETYPE_APPLICATION;
 579         newinfo->subtype = g_strdup("pgp-signature");
 580         g_hash_table_insert(newinfo->typeparameters, g_strdup("name"),
 581                              g_strdup("signature.asc"));
 582         newinfo->content = MIMECONTENT_MEM;
 583         newinfo->disposition = DISPOSITIONTYPE_ATTACHMENT;
 584         g_hash_table_insert(newinfo->dispositionparameters, g_strdup("filename"),
 585                             g_strdup("signature.asc"));
 586         newinfo->data.mem = g_malloc(len + 1);
 587         g_memmove(newinfo->data.mem, sigcontent, len);
 588         newinfo->data.mem[len] = '\0';
 589         g_node_append(sigmultipart->node, newinfo->node);
 590
 591         g_free(sigcontent);
 592         gpgme_release(ctx);
 593
 594         return TRUE;
 595 }
 596 gchar *pgpmime_get_encrypt_data(GSList *recp_names)
 597 {
 598         return sgpgme_get_encrypt_data(recp_names, GPGME_PROTOCOL_OpenPGP);
 599 }
 600
 601 static const gchar *pgpmime_get_encrypt_warning(void)
 602 {
 603         if (prefs_gpg_should_skip_encryption_warning(pgpmime_system.id))
 604                 return NULL;
 605         else
 606                 return _("Please note that email headers, like Subject, "
 607                          "are not encrypted by the PGP/Mime system.");
 608 }
 609
 610 static void pgpmime_inhibit_encrypt_warning(gboolean inhibit)
 611 {
 612         if (inhibit)
 613                 prefs_gpg_add_skip_encryption_warning(pgpmime_system.id);
 614         else
 615                 prefs_gpg_remove_skip_encryption_warning(pgpmime_system.id);
 616 }
 617
 618 gboolean pgpmime_encrypt(MimeInfo *mimeinfo, const gchar *encrypt_data)
 619 {
 620         MimeInfo *msgcontent, *encmultipart, *newinfo;
 621         FILE *fp;
 622         gchar *boundary, *enccontent;
 623         size_t len;
 624         gchar *textstr;
 625         gpgme_data_t gpgtext = NULL, gpgenc = NULL;
 626         gpgme_ctx_t ctx = NULL;
 627         gpgme_key_t *kset = NULL;
 628         gchar **fprs = g_strsplit(encrypt_data, " ", -1);
 629         gint i = 0;
 630         gpgme_error_t err;
 631
 632         while (fprs[i] && strlen(fprs[i])) {
 633                 i++;
 634         }
 635
 636         kset = g_malloc(sizeof(gpgme_key_t)*(i+1));
 637         memset(kset, 0, sizeof(gpgme_key_t)*(i+1));
 638         if ((err = gpgme_new(&ctx)) != GPG_ERR_NO_ERROR) {
 639                 debug_print(("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 640                 privacy_set_error(_("Couldn't initialize GPG context, %s"), gpgme_strerror(err));
 641                 g_free(kset);
 642                 return FALSE;
 643         }
 644         i = 0;
 645         while (fprs[i] && strlen(fprs[i])) {
 646                 gpgme_key_t key;
 647                 err = gpgme_get_key(ctx, fprs[i], &key, 0);
 648                 if (err) {
 649                         debug_print("can't add key '%s'[%d] (%s)\n", fprs[i],i, gpgme_strerror(err));
 650                         privacy_set_error(_("Couldn't add GPG key %s, %s"), fprs[i], gpgme_strerror(err));
 651                         g_free(kset);
 652                         return FALSE;
 653                 }
 654                 debug_print("found %s at %d\n", fprs[i], i);
 655                 kset[i] = key;
 656                 i++;
 657         }
 658
 659         debug_print("Encrypting message content\n");
 660
 661         /* remove content node from message */
 662         msgcontent = (MimeInfo *) mimeinfo->node->children->data;
 663         g_node_unlink(msgcontent->node);
 664
 665         /* create temporary multipart for content */
 666         encmultipart = procmime_mimeinfo_new();
 667         encmultipart->type = MIMETYPE_MULTIPART;
 668         encmultipart->subtype = g_strdup("encrypted");
 669         boundary = generate_mime_boundary("Encrypt");
 670         g_hash_table_insert(encmultipart->typeparameters, g_strdup("boundary"),
 671                             g_strdup(boundary));
 672         g_hash_table_insert(encmultipart->typeparameters, g_strdup("protocol"),
 673                             g_strdup("application/pgp-encrypted"));
 674         g_node_append(encmultipart->node, msgcontent->node);
 675
 676         /* write message content to temporary file */
 677         fp = my_tmpfile();
 678         if (fp == NULL) {
 679                 privacy_set_error(_("Couldn't create temporary file, %s"), strerror(errno));
 680                 g_free(kset);
 681                 return FALSE;
 682         }
 683         procmime_write_mimeinfo(encmultipart, fp);
 684         rewind(fp);
 685
 686         /* read temporary file into memory */
 687         textstr = get_canonical_content(fp, boundary);
 688
 689         fclose(fp);
 690
 691         /* encrypt data */
 692         gpgme_data_new_from_mem(&gpgtext, textstr, (size_t)strlen(textstr), 0);
 693         gpgme_data_new(&gpgenc);
 694         gpgme_set_armor(ctx, 1);
 695         cm_gpgme_data_rewind(gpgtext);
 696
 697         err = gpgme_op_encrypt(ctx, kset, GPGME_ENCRYPT_ALWAYS_TRUST, gpgtext, gpgenc);
 698
 699         enccontent = sgpgme_data_release_and_get_mem(gpgenc, &len);
 700         gpgme_data_release(gpgtext);
 701         g_free(textstr);
 702         g_free(kset);
 703
 704         if (enccontent == NULL || len <= 0) {
 705                 g_warning("sgpgme_data_release_and_get_mem failed");
 706                 privacy_set_error(_("Encryption failed, %s"), gpgme_strerror(err));
 707                 gpgme_release(ctx);
 708                 return FALSE;
 709         }
 710
 711         /* create encrypted multipart */
 712         g_node_unlink(msgcontent->node);
 713         procmime_mimeinfo_free_all(msgcontent);
 714         g_node_append(mimeinfo->node, encmultipart->node);
 715
 716         newinfo = procmime_mimeinfo_new();
 717         newinfo->type = MIMETYPE_APPLICATION;
 718         newinfo->subtype = g_strdup("pgp-encrypted");
 719         newinfo->content = MIMECONTENT_MEM;
 720         newinfo->data.mem = g_strdup("Version: 1\n");
 721         g_node_append(encmultipart->node, newinfo->node);
 722
 723         newinfo = procmime_mimeinfo_new();
 724         newinfo->type = MIMETYPE_APPLICATION;
 725         newinfo->subtype = g_strdup("octet-stream");
 726         newinfo->content = MIMECONTENT_MEM;
 727         newinfo->data.mem = g_malloc(len + 1);
 728         g_memmove(newinfo->data.mem, enccontent, len);
 729         newinfo->data.mem[len] = '\0';
 730         g_node_append(encmultipart->node, newinfo->node);
 731
 732         g_free(enccontent);
 733         gpgme_release(ctx);
 734
 735         return TRUE;
 736 }
 737
 738 static PrivacySystem pgpmime_system = {
 739         "pgpmime",                      /* id */
 740         "PGP MIME",                     /* name */
 741
 742         pgpmime_free_privacydata,       /* free_privacydata */
 743
 744         pgpmime_is_signed,              /* is_signed(MimeInfo *) */
 745         pgpmime_check_signature,        /* check_signature(MimeInfo *) */
 746         pgpmime_get_sig_status,         /* get_sig_status(MimeInfo *) */
 747         pgpmime_get_sig_info_short,     /* get_sig_info_short(MimeInfo *) */
 748         pgpmime_get_sig_info_full,      /* get_sig_info_full(MimeInfo *) */
 749
 750         pgpmime_is_encrypted,           /* is_encrypted(MimeInfo *) */
 751         pgpmime_decrypt,                /* decrypt(MimeInfo *) */
 752
 753         TRUE,
 754         pgpmime_sign,
 755
 756         TRUE,
 757         pgpmime_get_encrypt_data,
 758         pgpmime_encrypt,
 759         pgpmime_get_encrypt_warning,
 760         pgpmime_inhibit_encrypt_warning,
 761 };
 762
 763 void pgpmime_init()
 764 {
 765         privacy_register_system(&pgpmime_system);
 766 }
 767
 768 void pgpmime_done()
 769 {
 770         privacy_unregister_system(&pgpmime_system);
 771 }
 772
 773 struct PluginFeature *plugin_provides(void)
 774 {
 775         static struct PluginFeature features[] =
 776                 { {PLUGIN_PRIVACY, N_("PGP/Mime")},
 777                   {PLUGIN_NOTHING, NULL}};
 778         return features;
 779 }
 780 #endif /* USE_GPGME */