/**
* Extracts chunk length.
*
* @param[in] connp
* @returns HTP_OK on state change, HTP_ERROR on error, or HTP_DATA when more data is needed.
*/
htp_status_t htp_connp_RES_BODY_CHUNKED_LENGTH(htp_connp_t *connp) {
for (;;) {
OUT_COPY_BYTE_OR_RETURN(connp);
// Have we reached the end of the line?
if (connp->out_next_byte == LF) {
unsigned char *data;
size_t len;
if (htp_connp_res_consolidate_data(connp, &data, &len) != HTP_OK) {
return HTP_ERROR;
}
connp->out_tx->response_message_len += len;
#ifdef HTP_DEBUG
fprint_raw_data(stderr, "Chunk length line", data, len);
#endif
htp_chomp(data, &len);
connp->out_chunked_length = htp_parse_chunked_length(data, len);
htp_connp_res_clear_buffer(connp);
// Handle chunk length
if (connp->out_chunked_length > 0) {
// More data available
connp->out_state = htp_connp_RES_BODY_CHUNKED_DATA;
} else if (connp->out_chunked_length == 0) {
// End of data
connp->out_state = htp_connp_RES_HEADERS;
connp->out_tx->response_progress = HTP_RESPONSE_TRAILER;
} else {
// Invalid chunk length
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0,
"Response chunk encoding: Invalid chunk length: %d", connp->out_chunked_length);
return HTP_ERROR;
}
return HTP_OK;
}
}
return HTP_ERROR;
}
/**
* Parses response line.
*
* @param[in] connp
* @returns HTP_OK on state change, HTP_ERROR on error, or HTP_DATA when more data is needed.
*/
htp_status_t htp_connp_RES_LINE(htp_connp_t *connp) {
for (;;) {
// Get one byte
OUT_COPY_BYTE_OR_RETURN(connp);
// Have we reached the end of the line?
if (connp->out_next_byte == LF) {
unsigned char *data;
size_t len;
htp_connp_res_consolidate_data(connp, &data, &len);
#ifdef HTP_DEBUG
fprint_raw_data(stderr, __FUNCTION__, data, len);
#endif
// Is this a line that should be ignored?
if (htp_connp_is_line_ignorable(connp, data, len)) {
// We have an empty/whitespace line, which we'll note, ignore and move on
connp->out_tx->response_ignored_lines++;
// TODO How many lines are we willing to accept?
// Start again
htp_connp_res_clear_buffer(connp);
return HTP_OK;
}
// Deallocate previous response line allocations, which we would have on a 100 response.
if (connp->out_tx->response_line != NULL) {
bstr_free(connp->out_tx->response_line);
connp->out_tx->response_line = NULL;
}
if (connp->out_tx->response_protocol != NULL) {
bstr_free(connp->out_tx->response_protocol);
connp->out_tx->response_protocol = NULL;
}
if (connp->out_tx->response_status != NULL) {
bstr_free(connp->out_tx->response_status);
connp->out_tx->response_status = NULL;
}
if (connp->out_tx->response_message != NULL) {
bstr_free(connp->out_tx->response_message);
connp->out_tx->response_message = NULL;
}
// Process response line.
int chomp_result = htp_chomp(data, &len);
connp->out_tx->response_line = bstr_dup_mem(data, len);
if (connp->out_tx->response_line == NULL) return HTP_ERROR;
if (connp->cfg->parse_response_line(connp) != HTP_OK) return HTP_ERROR;
// If the response line is invalid, determine if it _looks_ like
// a response line. If it does not look like a line, process the
// data as a response body because that is what browsers do.
if (htp_treat_response_line_as_body(connp->out_tx)) {
connp->out_tx->response_content_encoding_processing = HTP_COMPRESSION_NONE;
int rc = htp_tx_res_process_body_data(connp->out_tx, data, len + chomp_result);
if (rc != HTP_OK) return rc;
// Continue to process response body. Because we don't have
// any headers to parse, we assume the body continues until
// the end of the stream.
connp->out_tx->response_transfer_coding = HTP_CODING_IDENTITY;
connp->out_tx->progress = HTP_RESPONSE_BODY;
connp->out_state = htp_connp_RES_BODY_IDENTITY_STREAM_CLOSE;
connp->out_body_data_left = -1;
return HTP_OK;
}
int rc = htp_tx_state_response_line(connp->out_tx);
if (rc != HTP_OK) return rc;
htp_connp_res_clear_buffer(connp);
// Move on to the next phase.
connp->out_state = htp_connp_RES_HEADERS;
connp->out_tx->progress = HTP_RESPONSE_HEADERS;
return HTP_OK;
}
}
return HTP_ERROR;
}
/**
* Parses response headers.
*
* @param[in] connp
* @returns HTP_OK on state change, HTP_ERROR on error, or HTP_DATA when more data is needed.
*/
htp_status_t htp_connp_RES_HEADERS(htp_connp_t *connp) {
for (;;) {
OUT_COPY_BYTE_OR_RETURN(connp);
// Have we reached the end of the line?
if (connp->out_next_byte == LF) {
unsigned char *data;
size_t len;
htp_connp_res_consolidate_data(connp, &data, &len);
#ifdef HTP_DEBUG
fprint_raw_data(stderr, __FUNCTION__, data, len);
#endif
// Should we terminate headers?
if (htp_connp_is_line_terminator(connp, data, len)) {
// Parse previous header, if any.
if (connp->out_header != NULL) {
if (connp->cfg->process_response_header(connp, bstr_ptr(connp->out_header),
bstr_len(connp->out_header)) != HTP_OK) return HTP_ERROR;
bstr_free(connp->out_header);
connp->out_header = NULL;
}
htp_connp_res_clear_buffer(connp);
// We've seen all response headers.
if (connp->out_tx->progress == HTP_RESPONSE_HEADERS) {
// Response headers.
// The next step is to determine if this response has a body.
connp->out_state = htp_connp_RES_BODY_DETERMINE;
} else {
// Response trailer.
// Finalize sending raw trailer data.
htp_status_t rc = htp_connp_res_receiver_finalize_clear(connp);
if (rc != HTP_OK) return rc;
// Run hook response_TRAILER.
rc = htp_hook_run_all(connp->cfg->hook_response_trailer, connp);
if (rc != HTP_OK) return rc;
// The next step is to finalize this response.
connp->out_state = htp_connp_RES_FINALIZE;
}
return HTP_OK;
}
htp_chomp(data, &len);
// Check for header folding.
if (htp_connp_is_line_folded(data, len) == 0) {
// New header line.
// Parse previous header, if any.
if (connp->out_header != NULL) {
if (connp->cfg->process_response_header(connp, bstr_ptr(connp->out_header),
bstr_len(connp->out_header)) != HTP_OK) return HTP_ERROR;
bstr_free(connp->out_header);
connp->out_header = NULL;
}
OUT_PEEK_NEXT(connp);
if (htp_is_folding_char(connp->out_next_byte) == 0) {
// Because we know this header is not folded, we can process the buffer straight away.
if (connp->cfg->process_response_header(connp, data, len) != HTP_OK) return HTP_ERROR;
} else {
// Keep the partial header data for parsing later.
connp->out_header = bstr_dup_mem(data, len);
if (connp->out_header == NULL) return HTP_ERROR;
}
} else {
// Folding; check that there's a previous header line to add to.
if (connp->out_header == NULL) {
// Invalid folding.
// Warn only once per transaction.
if (!(connp->out_tx->flags & HTP_INVALID_FOLDING)) {
connp->out_tx->flags |= HTP_INVALID_FOLDING;
htp_log(connp, HTP_LOG_MARK, HTP_LOG_WARNING, 0, "Invalid response field folding");
}
// Keep the header data for parsing later.
connp->out_header = bstr_dup_mem(data, len);
if (connp->out_header == NULL) return HTP_ERROR;
} else {
// Add to the existing header.
bstr *new_out_header = bstr_add_mem(connp->out_header, data, len);
if (new_out_header == NULL) return HTP_ERROR;
connp->out_header = new_out_header;
}
}
htp_connp_res_clear_buffer(connp);
}
}
return HTP_ERROR;
}