/**
* Determines whether inbound parsing needs to continue or stop. In
* case the data appears to be plain text HTTP, we try to continue.
*
* @param[in] connp
* @return HTP_OK if the parser can resume parsing, HTP_DATA_BUFFER if
* we need more data.
*/
htp_status_t htp_connp_REQ_CONNECT_PROBE_DATA(htp_connp_t *connp) {
for (;;) {//;i < max_read; i++) {
IN_PEEK_NEXT(connp);
// Have we reached the end of the line? For some reason
// we can't test after IN_COPY_BYTE_OR_RETURN */
if (connp->in_next_byte == LF || connp->in_next_byte == 0x00)
break;
IN_COPY_BYTE_OR_RETURN(connp);
}
unsigned char *data;
size_t len;
if (htp_connp_req_consolidate_data(connp, &data, &len) != HTP_OK) {
fprintf(stderr, "htp_connp_req_consolidate_data fail");
return HTP_ERROR;
}
#ifdef HTP_DEBUG
fprint_raw_data(stderr, "PROBING", data, len);
#endif
size_t pos = 0;
size_t mstart = 0;
// skip past leading whitespace. IIS allows this
while ((pos < len) && htp_is_space(data[pos]))
pos++;
if (pos)
mstart = pos;
// The request method starts at the beginning of the
// line and ends with the first whitespace character.
while ((pos < len) && (!htp_is_space(data[pos])))
pos++;
int methodi = HTP_M_UNKNOWN;
bstr *method = bstr_dup_mem(data + mstart, pos - mstart);
if (method) {
methodi = htp_convert_method_to_number(method);
bstr_free(method);
}
if (methodi != HTP_M_UNKNOWN) {
#ifdef HTP_DEBUG
fprint_raw_data(stderr, "htp_connp_REQ_CONNECT_PROBE_DATA: tunnel contains plain text HTTP", data, len);
#endif
connp->in_state = htp_connp_REQ_IDLE;
} else {
#ifdef HTP_DEBUG
fprint_raw_data(stderr, "htp_connp_REQ_CONNECT_PROBE_DATA: tunnel is not HTTP", data, len);
#endif
connp->in_status = HTP_STREAM_TUNNEL;
connp->out_status = HTP_STREAM_TUNNEL;
}
// not calling htp_connp_req_clear_buffer, we're not consuming the data
return HTP_OK;
}
/**
* Parses request 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_REQ_LINE(htp_connp_t *connp) {
for (;;) {
// Get one byte
IN_COPY_BYTE_OR_RETURN(connp);
// Have we reached the end of the line?
if (connp->in_next_byte == LF) {
unsigned char *data;
size_t len;
htp_connp_req_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->in_tx->request_ignored_lines++;
// TODO How many empty lines are we willing to accept?
htp_connp_req_clear_buffer(connp);
return HTP_OK;
}
// Process request line.
htp_chomp(data, &len);
connp->in_tx->request_line = bstr_dup_mem(data, len);
if (connp->in_tx->request_line == NULL) return HTP_ERROR;
if (connp->cfg->parse_request_line(connp) != HTP_OK) return HTP_ERROR;
// Finalize request line parsing.
if (htp_tx_state_request_line(connp->in_tx) != HTP_OK) return HTP_ERROR;
htp_connp_req_clear_buffer(connp);
return HTP_OK;
}
}
return HTP_ERROR;
}
/**
* 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_REQ_BODY_CHUNKED_LENGTH(htp_connp_t *connp) {
for (;;) {
IN_COPY_BYTE_OR_RETURN(connp);
// Have we reached the end of the line?
if (connp->in_next_byte == LF) {
unsigned char *data;
size_t len;
if (htp_connp_req_consolidate_data(connp, &data, &len) != HTP_OK) {
return HTP_ERROR;
}
connp->in_tx->request_message_len += len;
#ifdef HTP_DEBUG
fprint_raw_data(stderr, "Chunk length line", data, len);
#endif
htp_chomp(data, &len);
connp->in_chunked_length = htp_parse_chunked_length(data, len);
htp_connp_req_clear_buffer(connp);
// Handle chunk length.
if (connp->in_chunked_length > 0) {
// More data available.
connp->in_state = htp_connp_REQ_BODY_CHUNKED_DATA;
} else if (connp->in_chunked_length == 0) {
// End of data.
connp->in_state = htp_connp_REQ_HEADERS;
connp->in_tx->request_progress = HTP_REQUEST_TRAILER;
} else {
// Invalid chunk length.
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0, "Request chunk encoding: Invalid chunk length");
return HTP_ERROR;
}
return HTP_OK;
}
}
return HTP_ERROR;
}
/**
* Parse the request line.
*
* @param[in] connp
* @returns HTP_OK on succesful parse, HTP_ERROR on error.
*/
htp_status_t htp_connp_REQ_LINE_complete(htp_connp_t *connp) {
unsigned char *data;
size_t len;
if (htp_connp_req_consolidate_data(connp, &data, &len) != HTP_OK) {
return HTP_ERROR;
}
#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->in_tx->request_ignored_lines++;
htp_connp_req_clear_buffer(connp);
return HTP_OK;
}
// Process request line.
htp_chomp(data, &len);
connp->in_tx->request_line = bstr_dup_mem(data, len);
if (connp->in_tx->request_line == NULL)
return HTP_ERROR;
if (connp->cfg->parse_request_line(connp) != HTP_OK)
return HTP_ERROR;
// Finalize request line parsing.
if (htp_tx_state_request_line(connp->in_tx) != HTP_OK)
return HTP_ERROR;
htp_connp_req_clear_buffer(connp);
return HTP_OK;
}
/**
* Parses request 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_REQ_HEADERS(htp_connp_t *connp) {
for (;;) {
IN_COPY_BYTE_OR_RETURN(connp);
// Have we reached the end of the line?
if (connp->in_next_byte == LF) {
unsigned char *data;
size_t len;
htp_connp_req_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->in_header != NULL) {
if (connp->cfg->process_request_header(connp, bstr_ptr(connp->in_header),
bstr_len(connp->in_header)) != HTP_OK) return HTP_ERROR;
bstr_free(connp->in_header);
connp->in_header = NULL;
}
htp_connp_req_clear_buffer(connp);
// We've seen all the request headers.
return htp_tx_state_request_headers(connp->in_tx);
}
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->in_header != NULL) {
if (connp->cfg->process_request_header(connp, bstr_ptr(connp->in_header),
bstr_len(connp->in_header)) != HTP_OK) return HTP_ERROR;
bstr_free(connp->in_header);
connp->in_header = NULL;
}
IN_PEEK_NEXT(connp);
if (htp_is_folding_char(connp->in_next_byte) == 0) {
// Because we know this header is not folded, we can process the buffer straight away.
if (connp->cfg->process_request_header(connp, data, len) != HTP_OK) return HTP_ERROR;
} else {
// Keep the partial header data for parsing later.
connp->in_header = bstr_dup_mem(data, len);
if (connp->in_header == NULL) return HTP_ERROR;
}
} else {
// Folding; check that there's a previous header line to add to.
if (connp->in_header == NULL) {
// Invalid folding.
// Warn only once per transaction.
if (!(connp->in_tx->flags & HTP_INVALID_FOLDING)) {
connp->in_tx->flags |= HTP_INVALID_FOLDING;
htp_log(connp, HTP_LOG_MARK, HTP_LOG_WARNING, 0, "Invalid request field folding");
}
// Keep the header data for parsing later.
connp->in_header = bstr_dup_mem(data, len);
if (connp->in_header == NULL) return HTP_ERROR;
} else {
// Add to the existing header.
bstr *new_in_header = bstr_add_mem(connp->in_header, data, len);
if (new_in_header == NULL) return HTP_ERROR;
connp->in_header = new_in_header;
}
}
htp_connp_req_clear_buffer(connp);
}
}
return HTP_ERROR;
}
