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Diffstat (limited to 'camel/camel-pgp-mime.c')
| -rw-r--r-- | camel/camel-pgp-mime.c | 501 |
1 files changed, 501 insertions, 0 deletions
diff --git a/camel/camel-pgp-mime.c b/camel/camel-pgp-mime.c new file mode 100644 index 0000000000..6d256ba0b2 --- /dev/null +++ b/camel/camel-pgp-mime.c @@ -0,0 +1,501 @@ +/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */ +/* + * Authors: Jeffrey Stedfast <fejj@ximian.com> + * + * Copyright 2001 Ximian, Inc. (www.ximian.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Street #330, Boston, MA 02111-1307, USA. + * + */ + + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include "camel-pgp-mime.h" +#inlcude "camel-mime-filter-from.h" + +#include <stdlib.h> +#include <string.h> + +/** rfc2015 stuff (aka PGP/MIME) *******************************/ + +gboolean +camel_pgp_mime_is_rfc2015_signed (CamelMimePart *mime_part) +{ + CamelDataWrapper *wrapper; + CamelMultipart *mp; + CamelMimePart *part; + CamelContentType *type; + const gchar *param, *micalg; + int nparts; + + /* check that we have a multipart/signed */ + type = camel_mime_part_get_content_type (mime_part); + if (!header_content_type_is (type, "multipart", "signed")) + return FALSE; + + /* check that we have a protocol param with the value: "application/pgp-signed" */ + param = header_content_type_param (type, "protocol"); + if (!param || g_strcasecmp (param, "application/pgp-signature")) + return FALSE; + + /* check that we have a micalg parameter */ + micalg = header_content_type_param (type, "micalg"); + if (!micalg) + return FALSE; + + /* check that we have exactly 2 subparts */ + wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part)); + mp = CAMEL_MULTIPART (wrapper); + nparts = camel_multipart_get_number (mp); + if (nparts != 2) + return FALSE; + + /* The first part may be of any type except for + * application/pgp-signature - check it. */ + part = camel_multipart_get_part (mp, 0); + type = camel_mime_part_get_content_type (part); + if (header_content_type_is (type, "application", "pgp-signature")) + return FALSE; + + /* The second part should be application/pgp-signature. */ + part = camel_multipart_get_part (mp, 1); + type = camel_mime_part_get_content_type (part); + if (!header_content_type_is (type, "application", "pgp-signature")) + return FALSE; + + return TRUE; +} + +gboolean +camel_pgp_mime_is_rfc2015_encrypted (CamelMimePart *mime_part) +{ + CamelDataWrapper *wrapper; + CamelMultipart *mp; + CamelMimePart *part; + CamelContentType *type; + const gchar *param; + int nparts; + + /* check that we have a multipart/encrypted */ + type = camel_mime_part_get_content_type (mime_part); + if (!header_content_type_is (type, "multipart", "encrypted")) + return FALSE; + + /* check that we have a protocol param with the value: "application/pgp-encrypted" */ + param = header_content_type_param (type, "protocol"); + if (!param || g_strcasecmp (param, "application/pgp-encrypted")) + return FALSE; + + /* check that we have at least 2 subparts */ + wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part)); + mp = CAMEL_MULTIPART (wrapper); + nparts = camel_multipart_get_number (mp); + if (nparts < 2) + return FALSE; + + /* The first part should be application/pgp-encrypted */ + part = camel_multipart_get_part (mp, 0); + type = camel_mime_part_get_content_type (part); + if (!header_content_type_is (type, "application", "pgp-encrypted")) + return FALSE; + + /* The second part should be application/octet-stream - this + is the one we care most about */ + part = camel_multipart_get_part (mp, 1); + type = camel_mime_part_get_content_type (part); + if (!header_content_type_is (type, "application", "octet-stream")) + return FALSE; + + return TRUE; +} + + +static void +pgp_mime_part_sign_restore_part (CamelMimePart *mime_part, GSList *encodings) +{ + CamelDataWrapper *wrapper; + + wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part)); + if (!wrapper) + return; + + if (CAMEL_IS_MULTIPART (wrapper)) { + int parts, i; + + parts = camel_multipart_get_number (CAMEL_MULTIPART (wrapper)); + for (i = 0; i < parts; i++) { + CamelMimePart *part = camel_multipart_get_part (CAMEL_MULTIPART (wrapper), i); + + pgp_mime_part_sign_restore_part (part, encodings); + encodings = encodings->next; + } + } else { + CamelMimePartEncodingType encoding; + + encoding = GPOINTER_TO_INT (encodings->data); + + camel_mime_part_set_encoding (mime_part, encoding); + } +} + +static void +pgp_mime_part_sign_prepare_part (CamelMimePart *mime_part, GSList **encodings) +{ + CamelDataWrapper *wrapper; + int parts, i; + + wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part)); + if (!wrapper) + return; + + if (CAMEL_IS_MULTIPART (wrapper)) { + parts = camel_multipart_get_number (CAMEL_MULTIPART (wrapper)); + for (i = 0; i < parts; i++) { + CamelMimePart *part = camel_multipart_get_part (CAMEL_MULTIPART (wrapper), i); + + pgp_mime_part_sign_prepare_part (part, encodings); + } + } else { + CamelMimePartEncodingType encoding; + + encoding = camel_mime_part_get_encoding (mime_part); + + /* FIXME: find the best encoding for this part and use that instead?? */ + /* the encoding should really be QP or Base64 */ + if (encoding != CAMEL_MIME_PART_ENCODING_BASE64) + camel_mime_part_set_encoding (mime_part, CAMEL_MIME_PART_ENCODING_QUOTEDPRINTABLE); + + *encodings = g_slist_append (*encodings, GINT_TO_POINTER (encoding)); + } +} + + +/** + * camel_pgp_mime_part_sign: + * @context: PGP Context + * @mime_part: a MIME part that will be replaced by a pgp signed part + * @userid: userid to sign with + * @hash: one of CAMEL_PGP_HASH_TYPE_MD5 or CAMEL_PGP_HASH_TYPE_SHA1 + * @ex: exception which will be set if there are any errors. + * + * Constructs a PGP/MIME multipart in compliance with rfc2015 and + * replaces @part with the generated multipart/signed. On failure, + * @ex will be set and #part will remain untouched. + **/ +void +camel_pgp_mime_part_sign (CamelPgpContext *context, CamelMimePart **mime_part, const gchar *userid, + PgpHashType hash, CamelException *ex) +{ + CamelMimePart *part, *signed_part; + CamelMultipart *multipart; + CamelContentType *mime_type; + CamelStreamFilter *filtered_stream; + CamelMimeFilter *crlf_filter, *from_filter; + CamelStream *stream, *sigstream; + gchar *hash_type = NULL; + GSList *encodings = NULL; + + g_return_if_fail (*mime_part != NULL); + g_return_if_fail (CAMEL_IS_MIME_PART (*mime_part)); + g_return_if_fail (userid != NULL); + g_return_if_fail (hash != PGP_HASH_TYPE_NONE); + + part = *mime_part; + + /* Prepare all the parts for signing... */ + pgp_mime_part_sign_prepare_part (part, &encodings); + + /* get the cleartext */ + stream = camel_stream_mem_new (); + crlf_filter = camel_mime_filter_crlf_new (CAMEL_MIME_FILTER_CRLF_ENCODE, + CAMEL_MIME_FILTER_CRLF_MODE_CRLF_ONLY); + from_filter = CAMEL_MIME_FILTER (camel_mime_filter_from_new ()); + filtered_stream = camel_stream_filter_new_with_stream (stream); + camel_stream_filter_add (filtered_stream, CAMEL_MIME_FILTER (crlf_filter)); + camel_object_unref (CAMEL_OBJECT (crlf_filter)); + camel_stream_filter_add (filtered_stream, CAMEL_MIME_FILTER (from_filter)); + camel_object_unref (CAMEL_OBJECT (from_filter)); + camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (part), CAMEL_STREAM (filtered_stream)); + camel_object_unref (CAMEL_OBJECT (filtered_stream)); + + /* reset the stream */ + camel_stream_reset (stream); + + /* construct the signature stream */ + sigstream = camel_stream_mem_new (); + + /* get the signature */ + if (camel_pgp_sign (context, userid, hash, stream, sigstream, ex) == -1) { + camel_object_unref (CAMEL_OBJECT (stream)); + camel_object_unref (CAMEL_OBJECT (sigstream)); + + /* restore the original encoding */ + pgp_mime_part_sign_restore_part (part, encodings); + g_slist_free (encodings); + return; + } + camel_object_unref (CAMEL_OBJECT (stream)); + + /* we don't need these anymore... */ + g_slist_free (encodings); + + /* construct the pgp-signature mime part */ + d(fprintf (stderr, "signature:\n%*.s\n", CAMEL_STREAM_MEM (sigstream)->buf->len, + CAMEL_STREAM_MEM (sigstream)->buf->data)); + signed_part = camel_mime_part_new (); + camel_data_wrapper_construct_from_stream (CAMEL_DATA_WRAPPER (signed_part), sigstream); + camel_object_unref (CAMEL_OBJECT (sigstream)); + camel_mime_part_set_content_type (signed_part, "application/pgp-signature"); + + /* construct the container multipart/signed */ + switch (hash) { + case PGP_HASH_TYPE_MD5: + hash_type = "pgp-md5"; + break; + case PGP_HASH_TYPE_SHA1: + hash_type = "pgp-sha1"; + break; + default: + hash_type = "pgp-sha1"; + break; + } + + multipart = camel_multipart_new (); + + mime_type = header_content_type_new ("multipart", "signed"); + header_content_type_set_param (mime_type, "micalg", hash_type); + header_content_type_set_param (mime_type, "protocol", "application/pgp-signature"); + camel_data_wrapper_set_mime_type_field (CAMEL_DATA_WRAPPER (multipart), mime_type); + header_content_type_unref (mime_type); + + camel_multipart_set_boundary (multipart, NULL); + + /* add the parts to the multipart */ + camel_multipart_add_part (multipart, part); + camel_object_unref (CAMEL_OBJECT (part)); + camel_multipart_add_part (multipart, signed_part); + camel_object_unref (CAMEL_OBJECT (signed_part)); + + /* replace the input part with the output part */ + *mime_part = camel_mime_part_new (); + camel_medium_set_content_object (CAMEL_MEDIUM (*mime_part), + CAMEL_DATA_WRAPPER (multipart)); + camel_object_unref (CAMEL_OBJECT (multipart)); +} + + +/** + * camel_pgp_mime_part_verify: + * @context: PGP Context + * @mime_part: a multipart/signed MIME Part + * @ex: exception + * + * Returns a PgpValidity on success or NULL on fail. + **/ +PgpValidity * +camel_pgp_mime_part_verify (CamelPgpContext *context, CamelMimePart *mime_part, CamelException *ex) +{ + CamelDataWrapper *wrapper; + CamelMultipart *multipart; + CamelMimePart *part, *sigpart; + CamelStreamFilter *filtered_stream; + CamelMimeFilter *crlf_filter; + CamelStream *stream, *sigstream; + PgpValidity *valid; + + g_return_val_if_fail (mime_part != NULL, NULL); + g_return_val_if_fail (CAMEL_IS_MIME_PART (mime_part), NULL); + + if (!camel_pgp_mime_is_rfc2015_signed (mime_part)) + return NULL; + + wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part)); + multipart = CAMEL_MULTIPART (wrapper); + + /* get the plain part */ + part = camel_multipart_get_part (multipart, 0); + stream = camel_stream_mem_new (); + crlf_filter = camel_mime_filter_crlf_new (CAMEL_MIME_FILTER_CRLF_ENCODE, + CAMEL_MIME_FILTER_CRLF_MODE_CRLF_ONLY); + filtered_stream = camel_stream_filter_new_with_stream (stream); + camel_stream_filter_add (filtered_stream, CAMEL_MIME_FILTER (crlf_filter)); + camel_object_unref (CAMEL_OBJECT (crlf_filter)); + camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (part), CAMEL_STREAM (filtered_stream)); + camel_object_unref (CAMEL_OBJECT (filtered_stream)); + camel_stream_reset (stream); + + /* get the signed part */ + sigpart = camel_multipart_get_part (multipart, 1); + sigstream = camel_stream_mem_new (); + camel_data_wrapper_write_to_stream (camel_medium_get_content_object (CAMEL_MEDIUM (sigpart)), + sigstream); + camel_stream_reset (sigstream); + + /* verify */ + valid = camel_pgp_verify (context, stream, sigstream, ex); + + camel_object_unref (CAMEL_OBJECT (sigstream)); + camel_object_unref (CAMEL_OBJECT (stream)); + + return valid; +} + + +/** + * camel_pgp_mime_part_encrypt: + * @context: PGP Context + * @mime_part: a MIME part that will be replaced by a pgp encrypted part + * @recipients: list of recipient PGP Key IDs + * @ex: exception which will be set if there are any errors. + * + * Constructs a PGP/MIME multipart in compliance with rfc2015 and + * replaces #mime_part with the generated multipart/signed. On failure, + * #ex will be set and #part will remain untouched. + **/ +void +camel_pgp_mime_part_encrypt (CamelPgpContext *context, CamelMimePart **mime_part, + const GPtrArray *recipients, CamelException *ex) +{ + CamelMultipart *multipart; + CamelMimePart *part, *version_part, *encrypted_part; + CamelContentType *mime_type; + CamelStreamFilter *filtered_stream; + CamelMimeFilter *crlf_filter; + CamelStream *stream, *ciphertext; + + g_return_if_fail (*mime_part != NULL); + g_return_if_fail (CAMEL_IS_MIME_PART (*mime_part)); + g_return_if_fail (recipients != NULL); + + part = *mime_part; + + /* get the contents */ + stream = camel_stream_mem_new (); + crlf_filter = camel_mime_filter_crlf_new (CAMEL_MIME_FILTER_CRLF_ENCODE, + CAMEL_MIME_FILTER_CRLF_MODE_CRLF_ONLY); + filtered_stream = camel_stream_filter_new_with_stream (stream); + camel_stream_filter_add (filtered_stream, CAMEL_MIME_FILTER (crlf_filter)); + camel_object_unref (CAMEL_OBJECT (crlf_filter)); + camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (part), CAMEL_STREAM (filtered_stream)); + camel_object_unref (CAMEL_OBJECT (filtered_stream)); + camel_stream_reset (stream); + + /* pgp encrypt */ + ciphertext = camel_stream_mem_new (); + if (camel_pgp_encrypt (context, FALSE, NULL, recipients, stream, ciphertext, ex) == -1) { + camel_object_unref (CAMEL_OBJECT (stream)); + camel_object_unref (CAMEL_OBJECT (ciphertext)); + return; + } + + camel_object_unref (CAMEL_OBJECT (stream)); + camel_stream_reset (ciphertext); + + /* construct the version part */ + version_part = camel_mime_part_new (); + camel_mime_part_set_encoding (version_part, CAMEL_MIME_PART_ENCODING_7BIT); + camel_mime_part_set_content (version_part, "Version: 1", strlen ("Version: 1"), + "application/pgp-encrypted"); + + /* construct the pgp-encrypted mime part */ + encrypted_part = camel_mime_part_new (); + camel_data_wrapper_construct_from_stream (CAMEL_DATA_WRAPPER (encrypted_part), ciphertext); + camel_object_unref (CAMEL_OBJECT (ciphertext)); + camel_mime_part_set_content_type (encrypted_part, "application/octet-stream"); + camel_mime_part_set_encoding (encrypted_part, CAMEL_MIME_PART_ENCODING_7BIT); + + /* construct the container multipart/signed */ + multipart = camel_multipart_new (); + + mime_type = header_content_type_new ("multipart", "encrypted"); + header_content_type_set_param (mime_type, "protocol", "application/pgp-encrypted"); + camel_data_wrapper_set_mime_type_field (CAMEL_DATA_WRAPPER (multipart), mime_type); + header_content_type_unref (mime_type); + + camel_multipart_set_boundary (multipart, NULL); + + /* add the parts to the multipart */ + camel_multipart_add_part (multipart, version_part); + camel_object_unref (CAMEL_OBJECT (version_part)); + camel_multipart_add_part (multipart, encrypted_part); + camel_object_unref (CAMEL_OBJECT (encrypted_part)); + + /* replace the input part with the output part */ + camel_object_unref (CAMEL_OBJECT (*mime_part)); + *mime_part = camel_mime_part_new (); + camel_medium_set_content_object (CAMEL_MEDIUM (*mime_part), + CAMEL_DATA_WRAPPER (multipart)); + camel_object_unref (CAMEL_OBJECT (multipart)); +} + + +/** + * camel_pgp_mime_part_decrypt: + * @context: PGP Context + * @mime_part: a multipart/encrypted MIME Part + * @ex: exception + * + * Returns the decrypted MIME Part on success or NULL on fail. + **/ +CamelMimePart * +camel_pgp_mime_part_decrypt (CamelPgpContext *context, CamelMimePart *mime_part, CamelException *ex) +{ + CamelDataWrapper *wrapper; + CamelMultipart *multipart; + CamelMimePart *encrypted_part, *part; + CamelContentType *mime_type; + CamelStream *stream, *ciphertext; + + g_return_val_if_fail (mime_part != NULL, NULL); + g_return_val_if_fail (CAMEL_IS_MIME_PART (mime_part), NULL); + + /* make sure the mime part is a multipart/encrypted */ + if (!camel_pgp_mime_is_rfc2015_encrypted (mime_part)) + return NULL; + + wrapper = camel_medium_get_content_object (CAMEL_MEDIUM (mime_part)); + multipart = CAMEL_MULTIPART (wrapper); + + /* get the encrypted part (second part) */ + encrypted_part = camel_multipart_get_part (multipart, 1 /* second part starting at 0 */); + mime_type = camel_mime_part_get_content_type (encrypted_part); + if (!header_content_type_is (mime_type, "application", "octet-stream")) + return NULL; + + /* get the ciphertext */ + ciphertext = camel_stream_mem_new (); + camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (encrypted_part), ciphertext); + + /* get the cleartext */ + stream = camel_stream_mem_new (); + if (camel_pgp_decrypt (context, ciphertext, stream, ex) == -1) { + camel_object_unref (CAMEL_OBJECT (ciphertext)); + camel_object_unref (CAMEL_OBJECT (stream)); + return NULL; + } + + camel_object_unref (CAMEL_OBJECT (ciphertext)); + camel_stream_reset (stream); + + /* construct the new decrypted mime part from the stream */ + part = camel_mime_part_new (); + camel_data_wrapper_construct_from_stream (CAMEL_DATA_WRAPPER (part), stream); + camel_object_unref (CAMEL_OBJECT (stream)); + + return part; +} |