/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* mail-crypto.c: OpenPGP en/decryption & signature code
*
* FIXME FIXME FIXME: This should be in its own library or component
*/
/*
* Authors:
* Nathan Thompson-Amato <ndt@jps.net>
* Dan Winship <danw@helixcode.com>
* Jeffrey Stedfast <fejj@helixcode.com>
*
* Copyright 2000, Helix Code, Inc. (http://www.helixcode.com)
* Copyright 2000, Nathan Thompson-Amato
* Copyright 1999, 2000, Anthony Mulcahy
*
* 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.
*
*/
#include <config.h>
#include <stdlib.h>
#include <string.h>
#include "mail-crypto.h"
#include "mail-session.h"
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <signal.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <termios.h>
#include <unistd.h>
#include <signal.h>
#include <camel/camel-mime-filter-from.h>
/** rfc2015 stuff *******************************/
gboolean
mail_crypto_is_rfc2015_signed (CamelMimePart *mime_part)
{
CamelDataWrapper *wrapper;
CamelMultipart *mp;
CamelMimePart *part;
CamelContentType *type;
const gchar *param;
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-signed\""))
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-siganture"))
return FALSE;
/* FIXME: Implement multisig stuff */
return TRUE;
}
gboolean
mail_crypto_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;
}
/**
* pgp_mime_part_sign:
* @mime_part: a MIME part that will be replaced by a pgp signed part
* @userid: userid to sign with
* @hash: one of PGP_HASH_TYPE_MD5 or 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
pgp_mime_part_sign (CamelMimePart **mime_part, const gchar *userid, PgpHashType hash, CamelException *ex)
{
CamelMimePart *part, *signed_part;
CamelMultipart *multipart;
CamelMimePartEncodingType encoding;
CamelContentType *mime_type;
CamelStreamFilter *filtered_stream;
CamelMimeFilter *crlf_filter, *from_filter;
CamelStream *stream;
GByteArray *array;
gchar *cleartext, *signature;
gchar *hash_type;
gint clearlen;
g_return_if_fail (*mime_part != NULL);
g_return_if_fail (userid != NULL);
g_return_if_fail (hash != PGP_HASH_TYPE_NONE);
part = *mime_part;
encoding = camel_mime_part_get_encoding (part);
/* the encoding should really be QP or Base64 */
if (encoding != CAMEL_MIME_PART_ENCODING_BASE64)
camel_mime_part_set_encoding (part, CAMEL_MIME_PART_ENCODING_QUOTEDPRINTABLE);
/* get the cleartext */
array = g_byte_array_new ();
stream = camel_stream_mem_new_with_byte_array (array);
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_stream_filter_add (filtered_stream, CAMEL_MIME_FILTER (from_filter));
camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (part), CAMEL_STREAM (filtered_stream));
camel_object_unref (CAMEL_OBJECT (filtered_stream));
camel_object_unref (CAMEL_OBJECT (stream));
cleartext = array->data;
clearlen = array->len;
/* get the signature */
signature = openpgp_sign (cleartext, clearlen, userid, hash, ex);
g_byte_array_free (array, TRUE);
if (camel_exception_is_set (ex)) {
/* restore the original encoding */
camel_mime_part_set_encoding (part, encoding);
return;
}
/* construct the pgp-signature mime part */
fprintf (stderr, "signature:\n%s\n", signature);
signed_part = camel_mime_part_new ();
camel_mime_part_set_content (signed_part, signature, strlen (signature),
"application/pgp-signature");
g_free (signature);
camel_mime_part_set_encoding (signed_part, CAMEL_MIME_PART_ENCODING_DEFAULT);
/* construct the container multipart/signed */
multipart = camel_multipart_new ();
camel_data_wrapper_set_mime_type (CAMEL_DATA_WRAPPER (multipart),
"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 = NULL;
}
mime_type = camel_data_wrapper_get_mime_type_field (CAMEL_DATA_WRAPPER (multipart));
header_content_type_set_param (mime_type, "micalg", hash_type);
header_content_type_set_param (mime_type, "protocol", "application/pgp-signature");
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));
}
/**
* pgp_mime_part_verify:
* @mime_part: a multipart/signed MIME Part
* @ex: exception
*
* Returns TRUE if the signature is valid otherwise returns
* FALSE. Note: you may want to check the exception if it fails as
* there may be useful information to give to the user; example:
* verification may have failed merely because the user doesn't have
* the sender's key on her system.
**/
gboolean
pgp_mime_part_verify (CamelMimePart *mime_part, CamelException *ex)
{
CamelDataWrapper *wrapper;
CamelMultipart *multipart;
CamelMimePart *part, *sigpart;
GByteArray *content, *sig;
CamelStreamFilter *filtered_stream;
CamelMimeFilter *crlf_filter;
CamelStream *stream;
gboolean valid = FALSE;
g_return_val_if_fail (mime_part != NULL, FALSE);
if (!mail_crypto_is_rfc2015_signed (mime_part))
return FALSE;
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);
content = g_byte_array_new ();
stream = camel_stream_mem_new_with_byte_array (content);
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_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (part), CAMEL_STREAM (filtered_stream));
camel_object_unref (CAMEL_OBJECT (filtered_stream));
camel_object_unref (CAMEL_OBJECT (stream));
/* get the signed part */
sigpart = camel_multipart_get_part (multipart, 1);
sig = g_byte_array_new ();
stream = camel_stream_mem_new_with_byte_array (sig);
camel_data_wrapper_write_to_stream (camel_medium_get_content_object (CAMEL_MEDIUM (sigpart)), stream);
camel_object_unref (CAMEL_OBJECT (stream));
/* verify */
valid = openpgp_verify (content->data, content->len,
sig->data, sig->len, ex);
g_byte_array_free (content, TRUE);
g_byte_array_free (sig, TRUE);
return valid;
}
/**
* pgp_mime_part_encrypt:
* @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
pgp_mime_part_encrypt (CamelMimePart **mime_part, const GPtrArray *recipients, CamelException *ex)
{
CamelMultipart *multipart;
CamelMimePart *part, *version_part, *encrypted_part;
CamelContentType *mime_type;
CamelStream *stream;
GByteArray *contents;
gchar *ciphertext;
g_return_if_fail (*mime_part != NULL);
g_return_if_fail (recipients != NULL);
part = *mime_part;
/* get the contents */
contents = g_byte_array_new ();
stream = camel_stream_mem_new_with_byte_array (contents);
camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (part), stream);
camel_object_unref (CAMEL_OBJECT (stream));
/* pgp encrypt */
ciphertext = openpgp_encrypt (contents->data,
contents->len,
recipients, FALSE, NULL, ex);
if (camel_exception_is_set (ex))
return;
/* 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_mime_part_set_encoding (encrypted_part, CAMEL_MIME_PART_ENCODING_7BIT);
camel_mime_part_set_content (encrypted_part, ciphertext, strlen (ciphertext),
"application/octet-stream");
g_free (ciphertext);
/* construct the container multipart/signed */
multipart = camel_multipart_new ();
camel_data_wrapper_set_mime_type (CAMEL_DATA_WRAPPER (multipart),
"multipart/encrypted");
camel_multipart_set_boundary (multipart, NULL);
mime_type = camel_data_wrapper_get_mime_type_field (CAMEL_DATA_WRAPPER (multipart));
header_content_type_set_param (mime_type, "protocol", "application/pgp-encrypted");
/* 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 */
*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));
/* destroy the original part */
camel_object_unref (CAMEL_OBJECT (part));
}
/**
* pgp_mime_part_decrypt:
* @mime_part: a multipart/encrypted MIME Part
* @ex: exception
*
* Returns the decrypted MIME Part on success or NULL on fail.
**/
CamelMimePart *
pgp_mime_part_decrypt (CamelMimePart *mime_part, CamelException *ex)
{
CamelDataWrapper *wrapper;
CamelMultipart *multipart;
CamelMimeParser *parser;
CamelMimePart *encrypted_part, *part;
CamelContentType *mime_type;
CamelStream *stream;
GByteArray *content;
gchar *cleartext, *ciphertext = NULL;
int cipherlen, clearlen;
g_return_val_if_fail (mime_part != NULL, NULL);
/* make sure the mime part is a multipart/encrypted */
if (!mail_crypto_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 */
content = g_byte_array_new ();
stream = camel_stream_mem_new_with_byte_array (content);
camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (encrypted_part), stream);
camel_object_unref (CAMEL_OBJECT (stream));
ciphertext = content->data;
cipherlen = content->len;
/* get the cleartext */
cleartext = openpgp_decrypt (ciphertext, cipherlen, &clearlen, ex);
g_byte_array_free (content, TRUE);
if (camel_exception_is_set (ex))
return NULL;
/* create a stream based on the returned cleartext */
stream = camel_stream_mem_new ();
camel_stream_write (stream, cleartext, clearlen);
camel_stream_reset (stream);
g_free (cleartext);
/* construct the new decrypted mime part from the stream */
part = camel_mime_part_new ();
parser = camel_mime_parser_new ();
camel_mime_parser_init_with_stream (parser, stream);
camel_mime_part_construct_from_parser (part, parser);
camel_object_unref (CAMEL_OBJECT (parser));
camel_object_unref (CAMEL_OBJECT (stream));
return part;
}
