Esempio n. 1
0
/**
 * 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;
}
Esempio n. 2
0
/**
 * 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;
}
Esempio n. 3
0
/**
 * 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;
}