static void astream_parse_header(struct attachment_istream *astream,
struct message_header_line *hdr)
{
if (!hdr->continued) {
stream_add_data(astream, hdr->name, hdr->name_len);
stream_add_data(astream, hdr->middle, hdr->middle_len);
}
stream_add_data(astream, hdr->value, hdr->value_len);
if (!hdr->no_newline) {
if (hdr->crlf_newline)
stream_add_data(astream, "\r\n", 2);
else
stream_add_data(astream, "\n", 1);
}
if (hdr->continues) {
hdr->use_full_value = TRUE;
return;
}
if (strcasecmp(hdr->name, "Content-Type") == 0)
parse_content_type(astream, hdr);
else if (strcasecmp(hdr->name, "Content-Disposition") == 0)
parse_content_disposition(astream, hdr);
}
static void astream_add_body(struct attachment_istream *astream,
const struct message_block *block)
{
struct attachment_istream_part *part = &astream->part;
buffer_t *part_buf;
size_t new_size;
switch (part->state) {
case MAIL_ATTACHMENT_STATE_NO:
stream_add_data(astream, block->data, block->size);
break;
case MAIL_ATTACHMENT_STATE_MAYBE:
/* we'll write data to in-memory buffer until we reach
attachment min_size */
if (part->part_buf == NULL) {
part->part_buf =
buffer_create_dynamic(default_pool,
astream->set.min_size);
}
part_buf = part->part_buf;
new_size = part_buf->used + block->size;
if (new_size < astream->set.min_size) {
buffer_append(part_buf, block->data, block->size);
break;
}
/* attachment is large enough. we'll first copy the buffered
data from memory to temp file */
if (astream_open_output(astream) < 0) {
/* failed, fallback to just saving it inline */
part->state = MAIL_ATTACHMENT_STATE_NO;
stream_add_data(astream, part_buf->data, part_buf->used);
stream_add_data(astream, block->data, block->size);
break;
}
part->state = MAIL_ATTACHMENT_STATE_YES;
astream_try_base64_decode(part, part_buf->data, part_buf->used);
hash_format_loop(astream->set.hash_format,
part_buf->data, part_buf->used);
o_stream_nsend(part->temp_output,
part_buf->data, part_buf->used);
buffer_set_used_size(part_buf, 0);
/* fall through to write the new data to temp file */
case MAIL_ATTACHMENT_STATE_YES:
astream_try_base64_decode(part, block->data, block->size);
hash_format_loop(astream->set.hash_format,
block->data, block->size);
o_stream_nsend(part->temp_output, block->data, block->size);
break;
}
}
static int
astream_end_of_part(struct attachment_istream *astream)
{
struct attachment_istream_part *part = &astream->part;
int ret = 0;
/* MIME part changed. we're now parsing the end of a boundary,
possibly followed by message epilogue */
switch (part->state) {
case MAIL_ATTACHMENT_STATE_NO:
break;
case MAIL_ATTACHMENT_STATE_MAYBE:
/* MIME part wasn't large enough to be an attachment */
if (part->part_buf != NULL) {
stream_add_data(astream, part->part_buf->data,
part->part_buf->used);
ret = part->part_buf->used > 0 ? 1 : 0;
}
break;
case MAIL_ATTACHMENT_STATE_YES:
if (astream_part_finish(astream) < 0)
ret = -1;
break;
}
part->state = MAIL_ATTACHMENT_STATE_NO;
astream_part_reset(astream);
return ret;
}
static int
astream_end_of_part(struct attachment_istream *astream, const char **error_r)
{
struct attachment_istream_part *part = &astream->part;
size_t old_size;
int ret = 0;
/* MIME part changed. we're now parsing the end of a boundary,
possibly followed by message epilogue */
switch (part->state) {
case MAIL_ATTACHMENT_STATE_NO:
break;
case MAIL_ATTACHMENT_STATE_MAYBE:
/* MIME part wasn't large enough to be an attachment */
if (part->part_buf != NULL) {
stream_add_data(astream, part->part_buf->data,
part->part_buf->used);
ret = part->part_buf->used > 0 ? 1 : 0;
}
break;
case MAIL_ATTACHMENT_STATE_YES:
old_size = astream->istream.pos - astream->istream.skip;
if (astream_part_finish(astream, error_r) < 0)
ret = -1;
else {
/* finished base64 may have added a few more trailing
bytes to the stream */
ret = astream->istream.pos -
astream->istream.skip - old_size;
}
break;
}
part->state = MAIL_ATTACHMENT_STATE_NO;
astream_part_reset(astream);
return ret;
}
static int astream_decode_base64(struct attachment_istream *astream)
{
struct attachment_istream_part *part = &astream->part;
buffer_t *extra_buf = NULL;
struct istream *input, *base64_input;
struct ostream *output;
const unsigned char *data;
size_t size;
ssize_t ret;
buffer_t *buf;
int outfd;
bool failed = FALSE;
if (part->base64_bytes < astream->set.min_size ||
part->temp_output->offset > part->base64_bytes +
BASE64_ATTACHMENT_MAX_EXTRA_BYTES) {
/* only a small part of the MIME part is base64-encoded. */
return -1;
}
if (part->base64_line_blocks == 0) {
/* only one line of base64 */
part->base64_line_blocks = part->cur_base64_blocks;
i_assert(part->base64_line_blocks > 0);
}
/* decode base64 data and write it to another temp file */
outfd = astream->set.open_temp_fd(astream->context);
if (outfd == -1)
return -1;
buf = buffer_create_dynamic(default_pool, 1024);
input = i_stream_create_fd(part->temp_fd, IO_BLOCK_SIZE);
base64_input = i_stream_create_limit(input, part->base64_bytes);
output = o_stream_create_fd_file(outfd, 0, FALSE);
o_stream_cork(output);
hash_format_reset(astream->set.hash_format);
size_t bytes_needed = 1;
while ((ret = i_stream_read_bytes(base64_input, &data, &size,
bytes_needed)) > 0) {
buffer_set_used_size(buf, 0);
if (base64_decode(data, size, &size, buf) < 0) {
i_error("istream-attachment: BUG: "
"Attachment base64 data unexpectedly broke");
failed = TRUE;
break;
}
i_stream_skip(base64_input, size);
o_stream_nsend(output, buf->data, buf->used);
hash_format_loop(astream->set.hash_format,
buf->data, buf->used);
bytes_needed = i_stream_get_data_size(base64_input) + 1;
}
if (ret != -1) {
i_assert(failed);
} else if (base64_input->stream_errno != 0) {
i_error("istream-attachment: read(%s) failed: %s",
i_stream_get_name(base64_input),
i_stream_get_error(base64_input));
failed = TRUE;
}
if (o_stream_nfinish(output) < 0) {
i_error("istream-attachment: write(%s) failed: %s",
o_stream_get_name(output), o_stream_get_error(output));
failed = TRUE;
}
buffer_free(&buf);
i_stream_unref(&base64_input);
o_stream_unref(&output);
if (input->v_offset != part->temp_output->offset && !failed) {
/* write the rest of the data to the message stream */
extra_buf = buffer_create_dynamic(default_pool, 1024);
while ((ret = i_stream_read_more(input, &data, &size)) > 0) {
buffer_append(extra_buf, data, size);
i_stream_skip(input, size);
}
i_assert(ret == -1);
if (input->stream_errno != 0) {
i_error("istream-attachment: read(%s) failed: %s",
i_stream_get_name(input),
i_stream_get_error(input));
failed = TRUE;
}
}
i_stream_unref(&input);
if (failed) {
i_close_fd(&outfd);
return -1;
}
/* successfully wrote it. switch to using it. */
o_stream_destroy(&part->temp_output);
i_close_fd(&part->temp_fd);
part->temp_fd = outfd;
if (extra_buf != NULL) {
stream_add_data(astream, extra_buf->data, extra_buf->used);
buffer_free(&extra_buf);
}
return 0;
}
