/* -*- 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-smime.h"
#include "camel-mime-filter-from.h"
#include "camel-mime-filter-crlf.h"
#include "camel-stream-filter.h"
#include "camel-stream-mem.h"
#include "camel-multipart.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define d(x) x
/** rfc2633 stuff (aka S/MIME v3) ********************************/
gboolean
camel_smime_is_smime_v3_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/pkcs7-signature" */
param = header_content_type_param (type, "protocol");
if (!param || g_strcasecmp (param, "application/pkcs7-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/pkcs7-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", "pkcs7-signature"))
return FALSE;
/* The second part should be application/pkcs7-signature. */
part = camel_multipart_get_part (mp, 1);
type = camel_mime_part_get_content_type (part);
if (!header_content_type_is (type, "application", "pkcs7-signature"))
return FALSE;
return TRUE;
}
gboolean
camel_smime_is_smime_v3_encrypted (CamelMimePart *mime_part)
{
char *types[] = { "p7m", "p7c", "p7s", NULL };
const gchar *param, *filename;
CamelContentType *type;
int i;
/* check that we have a application/pkcs7-mime part */
type = camel_mime_part_get_content_type (mime_part);
if (header_content_type_is (type, "application", "pkcs7-mime")) {
/* check to make sure it's an encrypted pkcs7-mime part? */
return TRUE;
}
if (header_content_type_is (type, "application", "octent-stream")) {
/* check to see if we have a paremeter called "smime-type" */
param = header_content_type_param (type, "smime-type");
if (param)
return TRUE;
/* check to see if there is a name param and if it has a smime extension */
param = header_content_type_param (type, "smime-type");
if (param && *param && strlen (param) > 4) {
for (i = 0; types[i]; i++)
if (!g_strcasecmp (param + strlen (param)-4, types[i]))
return TRUE;
}
/* check to see if there is a name param and if it has a smime extension */
filename = camel_mime_part_get_filename (mime_part);
if (filename && *filename && strlen (filename) > 4) {
for (i = 0; types[i]; i++)
if (!g_strcasecmp (filename + strlen (filename)-4, types[i]))
return TRUE;
}
}
return FALSE;
}
static void
smime_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);
smime_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
smime_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);
smime_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_smime_part_sign:
* @context: S/MIME Context
* @mime_part: a MIME part that will be replaced by an S/MIME signed part
* @userid: userid to sign with
* @hash: one of CAMEL_CIPHER_HASH_TYPE_MD5 or CAMEL_CIPHER_HASH_TYPE_SHA1
* @ex: exception which will be set if there are any errors.
*
* Constructs a S/MIME multipart in compliance with rfc2015/rfc2633 and
* replaces @part with the generated multipart/signed. On failure,
* @ex will be set and #part will remain untouched.
**/
void
camel_smime_part_sign (CamelSMimeContext *context, CamelMimePart **mime_part, const char *userid,
CamelCipherHash 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);
part = *mime_part;
/* Prepare all the parts for signing... */
smime_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 ();
switch (hash) {
case CAMEL_CIPHER_HASH_MD5:
hash_type = "md5";
break;
case CAMEL_CIPHER_HASH_SHA1:
hash_type = "sha1";
break;
default:
/* set a reasonable default */
hash = CAMEL_CIPHER_HASH_SHA1;
hash_type = "sha1";
break;
}
/* get the signature */
if (camel_smime_sign (context, userid, hash, stream, sigstream, ex) == -1) {
camel_object_unref (CAMEL_OBJECT (stream));
camel_object_unref (CAMEL_OBJECT (sigstream));
/* restore the original encoding */
smime_part_sign_restore_part (part, encodings);
g_slist_free (encodings);
return;
}
camel_object_unref (CAMEL_OBJECT (stream));
camel_stream_reset (sigstream);
/* we don't need these anymore... */
g_slist_free (encodings);
/* construct the pkcs7-signature mime part */
signed_part = camel_mime_part_new ();
camel_mime_part_set_content (signed_part, CAMEL_STREAM_MEM (sigstream)->buffer->data,
CAMEL_STREAM_MEM (sigstream)->buffer->len,
"application/pkcs7-signature");
camel_object_unref (CAMEL_OBJECT (sigstream));
camel_mime_part_set_encoding (signed_part, CAMEL_MIME_PART_ENCODING_BASE64);
camel_mime_part_set_filename (signed_part, "smime.p7s");
/* construct the container multipart/signed */
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/pkcs7-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_smime_part_verify:
* @context: S/MIME Context
* @mime_part: a multipart/signed MIME Part
* @ex: exception
*
* Returns a CamelCipherValidity on success or NULL on fail.
**/
CamelCipherValidity *
camel_smime_part_verify (CamelSMimeContext *context, CamelMimePart *mime_part, CamelException *ex)
{
CamelDataWrapper *wrapper;
CamelMultipart *multipart;
CamelMimePart *part, *sigpart;
CamelStreamFilter *filtered_stream;
CamelMimeFilter *crlf_filter, *from_filter;
CamelStream *stream, *sigstream;
CamelCipherValidity *valid;
g_return_val_if_fail (mime_part != NULL, NULL);
g_return_val_if_fail (CAMEL_IS_MIME_PART (mime_part), NULL);
if (!camel_smime_is_smime_v3_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);
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));
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_smime_verify (context, stream, sigstream, ex);
camel_object_unref (CAMEL_OBJECT (sigstream));
camel_object_unref (CAMEL_OBJECT (stream));
return valid;
}
/**
* camel_smime_part_encrypt:
* @context: S/MIME 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_smime_part_encrypt (CamelSMimeContext *context, CamelMimePart **mime_part,
GPtrArray *recipients, CamelException *ex)
{
CamelMimePart *part, *encrypted_part;
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);
/* smime encrypt */
ciphertext = camel_stream_mem_new ();
if (camel_smime_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 encrypted mime part */
encrypted_part = camel_mime_part_new ();
camel_mime_part_set_content (encrypted_part, CAMEL_STREAM_MEM (ciphertext)->buffer->data,
CAMEL_STREAM_MEM (ciphertext)->buffer->len,
"application/pkcs7-mime; smime-type=enveloped-data");
camel_mime_part_set_encoding (encrypted_part, CAMEL_MIME_PART_ENCODING_BASE64);
camel_object_unref (CAMEL_OBJECT (ciphertext));
/* replace the input part with the output part */
camel_object_unref (CAMEL_OBJECT (*mime_part));
*mime_part = encrypted_part;
}
/**
* camel_smime_part_decrypt:
* @context: S/MIME Context
* @mime_part: a S/MIME encrypted MIME Part
* @ex: exception
*
* Returns the decrypted MIME Part on success or NULL on fail.
**/
CamelMimePart *
camel_smime_part_decrypt (CamelSMimeContext *context, CamelMimePart *mime_part, CamelException *ex)
{
CamelMimePart *part;
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 S/MIME encrypted */
if (!camel_smime_is_smime_v3_encrypted (mime_part))
return NULL;
/* get the ciphertext */
ciphertext = camel_stream_mem_new ();
camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (mime_part), ciphertext);
camel_stream_reset (ciphertext);
/* get the cleartext */
stream = camel_stream_mem_new ();
if (camel_smime_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;
}
