/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
* camel-multipart.c : Abstract class for a multipart
*
* Authors: Michael Zucchi <notzed@ximian.com>
*
* Copyright 2002 Ximian, Inc. (www.ximian.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* 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 Place, Suite 330, Boston, MA 02111-1307
* USA
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <errno.h>
#include "camel-mime-part.h"
#include "camel-mime-message.h"
#include "camel-mime-parser.h"
#include "camel-stream-mem.h"
#include "camel-multipart-signed.h"
#include "camel-mime-part.h"
#include "camel-exception.h"
#include "md5-utils.h"
#include "camel-stream-filter.h"
#include "camel-seekable-substream.h"
#include "camel-mime-filter-chomp.h"
#include "camel-mime-filter-crlf.h"
#include "camel-mime-filter-canon.h"
#define d(x)
static void signed_add_part(CamelMultipart *multipart, CamelMimePart *part);
static void signed_add_part_at(CamelMultipart *multipart, CamelMimePart *part, guint index);
static void signed_remove_part(CamelMultipart *multipart, CamelMimePart *part);
static CamelMimePart *signed_remove_part_at (CamelMultipart *multipart, guint index);
static CamelMimePart *signed_get_part(CamelMultipart *multipart, guint index);
static guint signed_get_number(CamelMultipart *multipart);
static int write_to_stream(CamelDataWrapper *data_wrapper, CamelStream *stream);
static void set_mime_type_field(CamelDataWrapper *data_wrapper, CamelContentType *mime_type);
static int construct_from_stream(CamelDataWrapper *data_wrapper, CamelStream *stream);
static int signed_construct_from_parser(CamelMultipart *multipart, struct _CamelMimeParser *mp);
static CamelMultipartClass *parent_class = NULL;
/* Returns the class for a CamelMultipartSigned */
#define CMP_CLASS(so) CAMEL_MULTIPART_SIGNED_CLASS (CAMEL_OBJECT_GET_CLASS(so))
/* Returns the class for a CamelDataWrapper */
#define CDW_CLASS(so) CAMEL_DATA_WRAPPER_CLASS (CAMEL_OBJECT_GET_CLASS(so))
static void
camel_multipart_signed_class_init (CamelMultipartSignedClass *camel_multipart_signed_class)
{
CamelDataWrapperClass *camel_data_wrapper_class = CAMEL_DATA_WRAPPER_CLASS(camel_multipart_signed_class);
CamelMultipartClass *mpclass = (CamelMultipartClass *)camel_multipart_signed_class;
parent_class = (CamelMultipartClass *)camel_multipart_get_type();
/* virtual method overload */
camel_data_wrapper_class->construct_from_stream = construct_from_stream;
camel_data_wrapper_class->write_to_stream = write_to_stream;
camel_data_wrapper_class->set_mime_type_field = set_mime_type_field;
mpclass->add_part = signed_add_part;
mpclass->add_part_at = signed_add_part_at;
mpclass->remove_part = signed_remove_part;
mpclass->remove_part_at = signed_remove_part_at;
mpclass->get_part = signed_get_part;
mpclass->get_number = signed_get_number;
mpclass->construct_from_parser = signed_construct_from_parser;
/*
mpclass->get_boundary = signed_get_boundary;
mpclass->set_boundary = signed_set_boundary;
*/
}
static void
camel_multipart_signed_init (gpointer object, gpointer klass)
{
CamelMultipartSigned *multipart = (CamelMultipartSigned *)object;
camel_data_wrapper_set_mime_type(CAMEL_DATA_WRAPPER(multipart), "multipart/signed");
multipart->start1 = -1;
}
static void
camel_multipart_signed_finalize (CamelObject *object)
{
CamelMultipartSigned *mps = (CamelMultipartSigned *)object;
g_free(mps->protocol);
g_free(mps->micalg);
if (mps->signature)
camel_object_unref((CamelObject *)mps->signature);
if (mps->content)
camel_object_unref((CamelObject *)mps->content);
if (mps->contentraw)
camel_object_unref((CamelObject *)mps->contentraw);
}
CamelType
camel_multipart_signed_get_type (void)
{
static CamelType camel_multipart_signed_type = CAMEL_INVALID_TYPE;
if (camel_multipart_signed_type == CAMEL_INVALID_TYPE) {
camel_multipart_signed_type = camel_type_register (camel_multipart_get_type (), "CamelMultipartSigned",
sizeof (CamelMultipartSigned),
sizeof (CamelMultipartSignedClass),
(CamelObjectClassInitFunc) camel_multipart_signed_class_init,
NULL,
(CamelObjectInitFunc) camel_multipart_signed_init,
(CamelObjectFinalizeFunc) camel_multipart_signed_finalize);
}
return camel_multipart_signed_type;
}
/**
* camel_multipart_signed_new:
*
* Create a new CamelMultipartSigned object.
*
* A MultipartSigned should be used to store and create parts of
* type "multipart/signed". This is because multipart/signed is
* entirely broken-by-design (tm) and uses completely
* different semantics to other mutlipart types. It must be treated
* as opaque data by any transport. See rfc 3156 for details.
*
* There are 3 ways to create the part:
* Use construct_from_stream. If this is used, then you must
* set the mime_type appropriately to match the data uses, so
* that the multiple parts my be extracted.
*
* Use construct_from_parser. The parser MUST be in the HSCAN_HEADER
* state, and the current content_type MUST be "multipart/signed" with
* the appropriate boundary and it SHOULD include the appropriate protocol
* and hash specifiers.
*
* Use sign_part. A signature part will automatically be created
* and the whole part may be written using write_to_stream to
* create a 'transport-safe' version (as safe as can be expected with
* such a broken specification).
*
* Return value: a new CamelMultipartSigned
**/
CamelMultipartSigned *
camel_multipart_signed_new (void)
{
CamelMultipartSigned *multipart;
multipart = (CamelMultipartSigned *)camel_object_new(CAMEL_MULTIPART_SIGNED_TYPE);
return multipart;
}
/* yeah yuck.
Well, we could probably use the normal mime parser, but then it would change our
headers.
This is good enough ... till its not! */
static int
parse_content(CamelMultipartSigned *mps)
{
CamelMultipart *mp = (CamelMultipart *)mps;
char *start, *end, *start2, *end2, *last;
CamelStreamMem *mem;
char *bound;
const char *boundary;
boundary = camel_multipart_get_boundary(mp);
if (boundary == NULL) {
g_warning("Trying to get multipart/signed content without setting boundary first");
return -1;
}
/* turn it into a string, and 'fix' it up */
/* this is extremely dodgey but should work! */
mem = (CamelStreamMem *)((CamelDataWrapper *)mps)->stream;
if (mem == NULL) {
g_warning("Trying to parse multipart/signed without constructing first");
return -1;
}
camel_stream_write((CamelStream *)mem, "", 1);
g_byte_array_set_size(mem->buffer, mem->buffer->len-1);
last = mem->buffer->data + mem->buffer->len;
bound = alloca(strlen(boundary)+5);
sprintf(bound, "--%s", boundary);
start = strstr(mem->buffer->data, bound);
if (start == NULL) {
printf("construct from stream, cannot find first boundary\n");
return -1;
}
if (start > (char *)mem->buffer->data) {
char *tmp = g_strndup(mem->buffer->data, start-(char *)mem->buffer->data-1);
camel_multipart_set_preface(mp, tmp);
g_free(tmp);
}
start += strlen(bound)+1;
if (start >= last)
return -1;
end = strstr(start, bound);
if (end == NULL) {
printf("construct from stream, cannot find second boundary\n");
return -1;
}
start2 = end + strlen(bound)+1;
if (start2 >= last)
return -1;
sprintf(bound, "--%s--", boundary);
end2 = strstr(start2, bound);
if (end2 == NULL) {
printf("construct from stream, cannot find last boundary\n");
return -1;
}
if (end2+strlen(bound)+1 < last)
camel_multipart_set_postface(mp, end2+strlen(bound)+1);
mps->start1 = start-(char *)mem->buffer->data;
mps->end1 = end-(char *)mem->buffer->data-1;
mps->start2 = start2-(char *)mem->buffer->data;
mps->end2 = end2-(char *)mem->buffer->data-1;
return 0;
}
/* we snoop the mime type to get boundary and hash info */
static void
set_mime_type_field(CamelDataWrapper *data_wrapper, CamelContentType *mime_type)
{
CamelMultipartSigned *mps = (CamelMultipartSigned *)data_wrapper;
((CamelDataWrapperClass *)parent_class)->set_mime_type_field(data_wrapper, mime_type);
if (mime_type) {
const char *micalg, *protocol;
protocol = header_content_type_param(mime_type, "protocol");
g_free(mps->protocol);
mps->protocol = g_strdup(protocol);
micalg = header_content_type_param(mime_type, "micalg");
g_free(mps->micalg);
mps->micalg = g_strdup(micalg);
}
}
static void
signed_add_part(CamelMultipart *multipart, CamelMimePart *part)
{
g_warning("Cannot add parts to a signed part using add_part");
}
static void
signed_add_part_at(CamelMultipart *multipart, CamelMimePart *part, guint index)
{
g_warning("Cannot add parts to a signed part using add_part_at");
}
static void
signed_remove_part(CamelMultipart *multipart, CamelMimePart *part)
{
g_warning("Cannot remove parts from a signed part using remove_part");
}
static CamelMimePart *
signed_remove_part_at (CamelMultipart *multipart, guint index)
{
g_warning("Cannot remove parts from a signed part using remove_part");
return NULL;
}
static CamelMimePart *
signed_get_part(CamelMultipart *multipart, guint index)
{
CamelMultipartSigned *mps = (CamelMultipartSigned *)multipart;
CamelDataWrapper *dw = (CamelDataWrapper *)multipart;
CamelStream *stream;
switch (index) {
case CAMEL_MULTIPART_SIGNED_CONTENT:
if (mps->content)
return mps->content;
if (mps->contentraw) {
stream = mps->contentraw;
camel_object_ref((CamelObject *)stream);
} else if (mps->start1 == -1
&& parse_content(mps) == -1
&& (stream = ((CamelDataWrapper *)mps)->stream) == NULL) {
g_warning("Trying to get content on an invalid multipart/signed");
return NULL;
} else if (dw->stream == NULL) {
return NULL;
} else {
stream = camel_seekable_substream_new((CamelSeekableStream *)dw->stream, mps->start1, mps->end1);
}
camel_stream_reset(stream);
mps->content = camel_mime_part_new();
camel_data_wrapper_construct_from_stream((CamelDataWrapper *)mps->content, stream);
camel_object_unref((CamelObject *)stream);
return mps->content;
case CAMEL_MULTIPART_SIGNED_SIGNATURE:
if (mps->signature)
return mps->signature;
if (mps->start1 == -1
&& parse_content(mps) == -1) {
g_warning("Trying to get signature on invalid multipart/signed");
return NULL;
} else if (dw->stream == NULL) {
return NULL;
}
stream = camel_seekable_substream_new((CamelSeekableStream *)dw->stream, mps->start2, mps->end2);
camel_stream_reset(stream);
mps->signature = camel_mime_part_new();
camel_data_wrapper_construct_from_stream((CamelDataWrapper *)mps->signature, stream);
camel_object_unref((CamelObject *)stream);
return mps->signature;
default:
g_warning("trying to get object out of bounds for multipart");
}
return NULL;
}
static guint
signed_get_number(CamelMultipart *multipart)
{
CamelDataWrapper *dw = (CamelDataWrapper *)multipart;
CamelMultipartSigned *mps = (CamelMultipartSigned *)multipart;
/* check what we have, so we return something reasonable */
if ((mps->content || mps->contentraw) && mps->signature)
return 2;
if (mps->start1 == -1 && parse_content(mps) == -1) {
if (dw->stream == NULL)
return 0;
else
return 1;
} else {
return 2;
}
}
static void
set_stream(CamelMultipartSigned *mps, CamelStream *mem)
{
CamelDataWrapper *dw = (CamelDataWrapper *)mps;
if (dw->stream)
camel_object_unref((CamelObject *)dw->stream);
dw->stream = (CamelStream *)mem;
mps->start1 = -1;
if (mps->content) {
camel_object_unref((CamelObject *)mps->content);
mps->content = NULL;
}
if (mps->contentraw) {
camel_object_unref((CamelObject *)mps->contentraw);
mps->contentraw = NULL;
}
if (mps->signature) {
camel_object_unref((CamelObject *)mps->signature);
mps->signature = NULL;
}
}
static int
construct_from_stream(CamelDataWrapper *data_wrapper, CamelStream *stream)
{
CamelMultipartSigned *mps = (CamelMultipartSigned *)data_wrapper;
CamelStream *mem = camel_stream_mem_new();
if (camel_stream_write_to_stream(stream, mem) == -1)
return -1;
set_stream(mps, mem);
return 0;
}
static int
signed_construct_from_parser(CamelMultipart *multipart, struct _CamelMimeParser *mp)
{
int err;
struct _header_content_type *content_type;
CamelMultipartSigned *mps = (CamelMultipartSigned *)multipart;
char *buf;
unsigned int len;
CamelStream *mem;
/* we *must not* be in multipart state, otherwise the mime parser will
parse the headers which is a no no @#$@# stupid multipart/signed spec */
g_assert(camel_mime_parser_state(mp) == HSCAN_HEADER);
/* All we do is copy it to a memstream */
content_type = camel_mime_parser_content_type(mp);
camel_multipart_set_boundary(multipart, header_content_type_param(content_type, "boundary"));
mem = camel_stream_mem_new();
while (camel_mime_parser_step(mp, &buf, &len) != HSCAN_BODY_END)
camel_stream_write(mem, buf, len);
set_stream(mps, mem);
err = camel_mime_parser_errno(mp);
if (err != 0) {
errno = err;
return -1;
} else
return 0;
}
static int
write_to_stream (CamelDataWrapper *data_wrapper, CamelStream *stream)
{
CamelMultipartSigned *mps = (CamelMultipartSigned *)data_wrapper;
CamelMultipart *mp = (CamelMultipart *)mps;
const char *boundary;
int count, total=0;
/* we have 3 basic cases:
1. constructed, we write out the data wrapper stream we got
2. signed content, we create and write out a new stream
3. invalid
*/
/* 1 */
/* FIXME: locking? */
if (data_wrapper->stream) {
camel_stream_reset(data_wrapper->stream);
return camel_stream_write_to_stream(data_wrapper->stream, stream);
}
/* 3 */
if (mps->signature == NULL || mps->contentraw == NULL)
return -1;
/* 2 */
boundary = camel_multipart_get_boundary(mp);
if (mp->preface) {
count = camel_stream_write_string(stream, mp->preface);
if (count == -1)
return -1;
total += count;
}
/* first boundary */
count = camel_stream_printf(stream, "\n--%s\n", boundary);
if (count == -1)
return -1;
total += count;
/* output content part */
camel_stream_reset(mps->contentraw);
count = camel_stream_write_to_stream(mps->contentraw, stream);
if (count == -1)
return -1;
total += count;
/* boundary */
count = camel_stream_printf(stream, "\n--%s\n", boundary);
if (count == -1)
return -1;
total += count;
/* signature */
count = camel_data_wrapper_write_to_stream((CamelDataWrapper *)mps->signature, stream);
if (count == -1)
return -1;
total += count;
/* write the terminating boudary delimiter */
count = camel_stream_printf(stream, "\n--%s--\n", boundary);
if (count == -1)
return -1;
total += count;
/* and finally the postface */
if (mp->postface) {
count = camel_stream_write_string(stream, mp->postface);
if (count == -1)
return -1;
total += count;
}
return total;
}
/* See rfc3156, section 2 and others */
/* We do this simply: Anything not base64 must be qp
This is so that we can safely translate any occurance of "From "
into the quoted-printable escaped version safely. */
static void
prepare_sign(CamelMimePart *mime_part)
{
CamelDataWrapper *wrapper;
CamelMimePartEncodingType encoding;
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((CamelMultipart *)wrapper);
for (i = 0; i < parts; i++)
prepare_sign(camel_multipart_get_part((CamelMultipart *)wrapper, i));
} else if (CAMEL_IS_MIME_MESSAGE (wrapper)) {
prepare_sign((CamelMimePart *)wrapper);
} else {
encoding = camel_mime_part_get_encoding(mime_part);
if (encoding != CAMEL_MIME_PART_ENCODING_BASE64
&& encoding != CAMEL_MIME_PART_ENCODING_QUOTEDPRINTABLE) {
camel_mime_part_set_encoding(mime_part, CAMEL_MIME_PART_ENCODING_QUOTEDPRINTABLE);
}
}
}
/**
* camel_multipart_signed_sign:
* @mps:
* @context: The CipherContext to use for signing.
* @content: CamelMimePart content you wish to sign/transport.
* @userid: The id of the signing key to use.
* @hash: The algorithm to use.
* @ex:
*
* Sign the part @content, and attach it as the first part
* (CAMEL_MULTIPART_SIGNED_CONTENT) of the multipart @mps. A
* signature object will be created and setup as the second part
* (CAMEL_MULTIPART_SIGNED_SIGNATURE) of the object. Once a part has
* been successfully signed the mutlipart is ready for transmission.
*
* This method should be used to create multipart/signed objects
* which are properly canoncalised before signing, etc.
*
* Return value: -1 on error, setting @ex appropriately. On error
* neither the content or signature parts will be setup.
**/
int
camel_multipart_signed_sign(CamelMultipartSigned *mps, CamelCipherContext *context, CamelMimePart *content, const char *userid, CamelCipherHash hash, CamelException *ex)
{
CamelMimeFilter *canon_filter;
CamelStream *sigstream, *mem;
CamelStreamFilter *filter;
CamelContentType *mime_type;
CamelMimePart *signature;
CamelDataWrapper *dw;
char *type;
/* this needs to be set */
g_return_val_if_fail(context->sign_protocol != NULL, -1);
prepare_sign(content);
mem = camel_stream_mem_new();
filter = camel_stream_filter_new_with_stream(mem);
canon_filter = camel_mime_filter_canon_new(CAMEL_MIME_FILTER_CANON_STRIP|CAMEL_MIME_FILTER_CANON_CRLF|CAMEL_MIME_FILTER_CANON_FROM);
camel_stream_filter_add(filter, (CamelMimeFilter *)canon_filter);
camel_object_unref((CamelObject *)canon_filter);
camel_data_wrapper_write_to_stream((CamelDataWrapper *)content, (CamelStream *)filter);
camel_stream_flush((CamelStream *)filter);
camel_object_unref((CamelObject *)filter);
camel_stream_reset(mem);
#if 0
printf("-- Signing:\n");
fwrite(((CamelStreamMem *)mem)->buffer->data, ((CamelStreamMem *)mem)->buffer->len, 1, stdout);
printf("-- end\n");
#endif
sigstream = camel_stream_mem_new();
if (camel_cipher_sign(context, userid, hash, mem, sigstream, ex) == -1) {
camel_object_unref((CamelObject *)mem);
camel_object_unref((CamelObject *)sigstream);
return -1;
}
/* create the signature wrapper object */
signature = camel_mime_part_new();
dw = camel_data_wrapper_new();
type = alloca(strlen(context->sign_protocol) + 32);
sprintf(type, "%s; name=signature.asc", context->sign_protocol);
camel_data_wrapper_set_mime_type(dw, type);
camel_stream_reset(sigstream);
camel_data_wrapper_construct_from_stream(dw, sigstream);
camel_object_unref((CamelObject *)sigstream);
camel_medium_set_content_object((CamelMedium *)signature, dw);
camel_object_unref((CamelObject *)dw);
camel_mime_part_set_description(signature, _("This is a digitally signed message part"));
/* setup our mime type and boundary */
mime_type = header_content_type_new("multipart", "signed");
header_content_type_set_param(mime_type, "micalg", camel_cipher_hash_to_id(context, hash));
header_content_type_set_param(mime_type, "protocol", context->sign_protocol);
camel_data_wrapper_set_mime_type_field(CAMEL_DATA_WRAPPER (mps), mime_type);
header_content_type_unref(mime_type);
camel_multipart_set_boundary((CamelMultipart *)mps, NULL);
/* just keep the whole raw content. We dont *really* need to do this because
we know how we just proccessed it, but, well, better to be safe than sorry */
mps->signature = signature;
mps->contentraw = mem;
camel_stream_reset(mem);
/* clear the data-wrapper stream - tells write_to_stream to use the right object */
if (((CamelDataWrapper *)mps)->stream) {
camel_object_unref((CamelObject *) ((CamelDataWrapper *)mps)->stream);
((CamelDataWrapper *)mps)->stream = NULL;
}
return 0;
}
/**
* camel_multipart_signed_verify:
* @mps:
* @context:
* @ex:
*
* Verify a signed object. This may be used to verify newly signed
* objects as well as those created from external streams or parsers.
*
* Return value: A validity value, or NULL on error, setting @ex
* appropriately.
**/
CamelCipherValidity *
camel_multipart_signed_verify(CamelMultipartSigned *mps, CamelCipherContext *context, CamelException *ex)
{
CamelCipherValidity *valid;
CamelMimePart *sigpart;
CamelStream *sigstream, *constream;
/* we need to be able to verify stuff we just signed as well as stuff we loaded from a stream/parser */
if (mps->contentraw) {
constream = mps->contentraw;
camel_object_ref((CamelObject *)constream);
} else {
CamelStream *sub;
CamelMimeFilter *canon_filter;
if (mps->start1 == -1 && parse_content(mps) == -1) {
camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM, _("parse error"));
return NULL;
}
/* first, prepare our parts */
sub = camel_seekable_substream_new((CamelSeekableStream *)((CamelDataWrapper *)mps)->stream, mps->start1, mps->end1);
constream = (CamelStream *)camel_stream_filter_new_with_stream(sub);
camel_object_unref((CamelObject *)sub);
/* Note: see rfc2015 or rfc3156, section 5 */
canon_filter = camel_mime_filter_canon_new(CAMEL_MIME_FILTER_CANON_STRIP|CAMEL_MIME_FILTER_CANON_CRLF);
camel_stream_filter_add((CamelStreamFilter *)constream, (CamelMimeFilter *)canon_filter);
camel_object_unref((CamelObject *)canon_filter);
}
/* we do this as a normal mime part so we can have it handle transfer encoding etc */
sigstream = camel_stream_mem_new();
sigpart = camel_multipart_get_part((CamelMultipart *)mps, CAMEL_MULTIPART_SIGNED_SIGNATURE);
camel_data_wrapper_write_to_stream((CamelDataWrapper *)sigpart, sigstream);
camel_stream_reset(sigstream);
/* do the magic, the caller must supply the right context for this kind of object */
valid = camel_cipher_verify(context, camel_cipher_id_to_hash(context, mps->micalg), constream, sigstream, ex);
#if 0
{
CamelStream *sout = camel_stream_fs_new_with_fd(dup(0));
camel_stream_printf(sout, "-- Verifying:\n");
camel_stream_reset(constream);
camel_stream_write_to_stream(constream, sout);
camel_stream_printf(sout, "-- end\n");
camel_object_unref((CamelObject *)sout);
}
#endif
camel_object_unref((CamelObject *)constream);
camel_object_unref((CamelObject *)sigstream);
return valid;
}
