htp_status_t htp_tx_res_set_header(htp_tx_t *tx, const char *name, size_t name_len, const char *value, size_t value_len, enum htp_alloc_strategy_t alloc) { if ((tx == NULL) || (name == NULL) || (value == NULL)) return HTP_ERROR; htp_header_t *h = calloc(1, sizeof (htp_header_t)); if (h == NULL) return HTP_ERROR; h->name = copy_or_wrap_mem(name, name_len, alloc); if (h->name == NULL) { free(h); return HTP_ERROR; } h->value = copy_or_wrap_mem(value, value_len, alloc); if (h->value == NULL) { bstr_free(h->name); free(h); return HTP_ERROR; } if (htp_table_add(tx->response_headers, h->name, h) != HTP_OK) { bstr_free(h->name); bstr_free(h->value); free(h); return HTP_ERROR; } return HTP_OK; }
/** * Extract one request header. A header can span multiple lines, in * which case they will be folded into one before parsing is attempted. * * @param[in] connp * @param[in] data * @param[in] len * @return HTP_OK or HTP_ERROR */ htp_status_t htp_process_request_header_generic(htp_connp_t *connp, unsigned char *data, size_t len) { // Create a new header structure. htp_header_t *h = calloc(1, sizeof (htp_header_t)); if (h == NULL) return HTP_ERROR; // Now try to parse the header. if (htp_parse_request_header_generic(connp, h, data, len) != HTP_OK) { free(h); return HTP_ERROR; } #ifdef HTP_DEBUG fprint_bstr(stderr, "Header name", h->name); fprint_bstr(stderr, "Header value", h->value); #endif // Do we already have a header with the same name? htp_header_t *h_existing = htp_table_get(connp->in_tx->request_headers, h->name); if (h_existing != NULL) { // TODO Do we want to have a list of the headers that are // allowed to be combined in this way? // Add to the existing header. bstr *new_value = bstr_expand(h_existing->value, bstr_len(h_existing->value) + 2 + bstr_len(h->value)); if (new_value == NULL) { bstr_free(h->name); bstr_free(h->value); free(h); return HTP_ERROR; } h_existing->value = new_value; bstr_add_mem_noex(h_existing->value, ", ", 2); bstr_add_noex(h_existing->value, h->value); // The new header structure is no longer needed. bstr_free(h->name); bstr_free(h->value); free(h); // Keep track of repeated same-name headers. h_existing->flags |= HTP_FIELD_REPEATED; } else { // Add as a new header. htp_table_add(connp->in_tx->request_headers, h->name, h); } return HTP_OK; }
/** * Generic response header line(s) processor, which assembles folded lines * into a single buffer before invoking the parsing function. * * @param[in] connp * @param[in] data * @param[in] len * @return HTP status */ htp_status_t htp_process_response_header_generic(htp_connp_t *connp, unsigned char *data, size_t len) { // Create a new header structure. htp_header_t *h = calloc(1, sizeof (htp_header_t)); if (h == NULL) return HTP_ERROR; if (htp_parse_response_header_generic(connp, h, data, len) != HTP_OK) { free(h); return HTP_ERROR; } #ifdef HTP_DEBUG fprint_bstr(stderr, "Header name", h->name); fprint_bstr(stderr, "Header value", h->value); #endif // Do we already have a header with the same name? htp_header_t *h_existing = htp_table_get(connp->out_tx->response_headers, h->name); if (h_existing != NULL) { // Keep track of repeated same-name headers. h_existing->flags |= HTP_FIELD_REPEATED; // Having multiple C-L headers is against the RFC but many // browsers ignore the subsequent headers if the values are the same. if (bstr_cmp_c_nocase(h->name, "Content-Length") == 0) { // Don't use string comparison here because we want to // ignore small formatting differences. int64_t existing_cl, new_cl; existing_cl = htp_parse_content_length(h_existing->value); new_cl = htp_parse_content_length(h->value); if ((existing_cl == -1) || (new_cl == -1) || (existing_cl != new_cl)) { // Ambiguous response C-L value. htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0, "Ambiguous response C-L value"); bstr_free(h->name); bstr_free(h->value); free(h); return HTP_ERROR; } // Ignoring the new C-L header that has the same value as the previous ones. } else { // Add to the existing header. bstr *new_value = bstr_expand(h_existing->value, bstr_len(h_existing->value) + 2 + bstr_len(h->value)); if (new_value == NULL) { bstr_free(h->name); bstr_free(h->value); free(h); return HTP_ERROR; } h_existing->value = new_value; bstr_add_mem_noex(h_existing->value, (unsigned char *) ", ", 2); bstr_add_noex(h_existing->value, h->value); } // The new header structure is no longer needed. bstr_free(h->name); bstr_free(h->value); free(h); } else { // Add as a new header. if (htp_table_add(connp->out_tx->response_headers, h->name, h) != HTP_OK) { bstr_free(h->name); bstr_free(h->value); free(h); return HTP_ERROR; } } return HTP_OK; }
/** * Extract one request header. A header can span multiple lines, in * which case they will be folded into one before parsing is attempted. * * @param[in] connp * @return HTP_OK or HTP_ERROR */ int htp_process_request_header_generic(htp_connp_t *connp) { bstr *tempstr = NULL; unsigned char *data = NULL; size_t len = 0; // Create new header structure htp_header_t *h = calloc(1, sizeof (htp_header_t)); if (h == NULL) { return HTP_ERROR; } // Ensure we have the necessary header data in a single buffer if (connp->in_header_line_index + 1 == connp->in_header_line_counter) { // Single line htp_header_line_t *hl = htp_list_get(connp->in_tx->request_header_lines, connp->in_header_line_index); if (hl == NULL) { // Internal error free(h); return HTP_ERROR; } data = (unsigned char *)bstr_ptr(hl->line); len = bstr_len(hl->line); hl->header = h; } else { // Multiple lines (folded) int i = 0; for (i = connp->in_header_line_index; i < connp->in_header_line_counter; i++) { htp_header_line_t *hl = htp_list_get(connp->in_tx->request_header_lines, i); len += bstr_len(hl->line); } tempstr = bstr_alloc(len); if (tempstr == NULL) { free(h); return HTP_ERROR; } for (i = connp->in_header_line_index; i < connp->in_header_line_counter; i++) { htp_header_line_t *hl = htp_list_get(connp->in_tx->request_header_lines, i); unsigned char *line = bstr_ptr(hl->line); size_t llen = bstr_len(hl->line); htp_chomp((unsigned char *)line, &llen); bstr_add_mem_noex(tempstr, line, llen); hl->header = h; if (i != connp->in_header_line_index) { hl->flags |= HTP_FIELD_FOLDED; } } h->flags |= HTP_FIELD_FOLDED; data = (unsigned char *)bstr_ptr(tempstr); len = bstr_len(tempstr); } // Now try to parse the header if (htp_parse_request_header_generic(connp, h, data, len) != HTP_OK) { bstr_free(tempstr); free(h); return HTP_ERROR; } // Do we already have a header with the same name? htp_header_t *h_existing = htp_table_get(connp->in_tx->request_headers, h->name); if (h_existing != NULL) { // repeated header int i = 0; // TODO Do we want to keep a list of the headers that are // allowed to be combined in this way? // Add to existing header bstr *new_value = bstr_expand(h_existing->value, bstr_len(h_existing->value) + 2 + bstr_len(h->value)); if (new_value == NULL) { bstr_free(h->name); bstr_free(h->value); free(h); bstr_free(tempstr); return HTP_ERROR; } h_existing->value = new_value; bstr_add_mem_noex(h_existing->value, (unsigned char *)", ", 2); bstr_add_noex(h_existing->value, h->value); // replace the header references in all lines for (i = connp->in_header_line_index; i < connp->in_header_line_counter; i++) { htp_header_line_t *hl = htp_list_get(connp->in_tx->request_header_lines, i); hl->header = h_existing; } // The header fields are no longer needed bstr_free(h->name); bstr_free(h->value); free(h); // Keep track of same-name headers h_existing->flags |= HTP_FIELD_REPEATED; } else { // Add as a new header htp_table_add(connp->in_tx->request_headers, h->name, h); } bstr_free(tempstr); return HTP_OK; }