void htp_table_destroy(htp_table_t *table) {
if (table == NULL) return;
htp_table_clear(table);
htp_list_destroy(table->list);
table->list = NULL;
free(table);
}
/**
* Determines presence (and encoding) of a response body.
*
* @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_DETERMINE(htp_connp_t *connp) {
// If the request uses the CONNECT method, then not only are we
// to assume there's no body, but we need to ignore all
// subsequent data in the stream.
if (connp->out_tx->request_method_number == HTP_M_CONNECT) {
if ((connp->out_tx->response_status_number >= 200)
&& (connp->out_tx->response_status_number <= 299)) {
// This is a successful CONNECT stream, which means
// we need to switch into tunnelling mode.
connp->in_status = HTP_STREAM_TUNNEL;
connp->out_status = HTP_STREAM_TUNNEL;
connp->out_state = htp_connp_RES_FINALIZE;
return HTP_OK;
} else {
// This is a failed CONNECT stream, which means that
// we can unblock request parsing
connp->in_status = HTP_STREAM_DATA;
// We are going to continue processing this transaction,
// adding a note for ourselves to stop at the end (because
// we don't want to see the beginning of a new transaction).
connp->out_data_other_at_tx_end = 1;
}
}
// Check for an interim "100 Continue" response. Ignore it if found, and revert back to RES_FIRST_LINE.
if (connp->out_tx->response_status_number == 100) {
if (connp->out_tx->seen_100continue != 0) {
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0, "Already seen 100-Continue.");
return HTP_ERROR;
}
// Ignore any response headers seen so far.
htp_header_t *h = NULL;
for (int i = 0, n = htp_table_size(connp->out_tx->response_headers); i < n; i++) {
h = htp_table_get_index(connp->out_tx->response_headers, i, NULL);
bstr_free(h->name);
bstr_free(h->value);
free(h);
}
htp_table_clear(connp->out_tx->response_headers);
// Expecting to see another response line next.
connp->out_state = htp_connp_RES_LINE;
connp->out_tx->progress = HTP_RESPONSE_LINE;
connp->out_tx->seen_100continue++;
return HTP_OK;
}
// 1. Any response message which MUST NOT include a message-body
// (such as the 1xx, 204, and 304 responses and any response to a HEAD
// request) is always terminated by the first empty line after the
// header fields, regardless of the entity-header fields present in the
// message.
if (((connp->out_tx->response_status_number >= 100) && (connp->out_tx->response_status_number <= 199))
|| (connp->out_tx->response_status_number == 204) || (connp->out_tx->response_status_number == 304)
|| (connp->out_tx->request_method_number == HTP_M_HEAD)) {
// There's no response body
connp->out_tx->response_transfer_coding = HTP_CODING_NO_BODY;
connp->out_state = htp_connp_RES_FINALIZE;
} else {
// We have a response body
htp_header_t *ct = htp_table_get_c(connp->out_tx->response_headers, "content-type");
htp_header_t *cl = htp_table_get_c(connp->out_tx->response_headers, "content-length");
htp_header_t *te = htp_table_get_c(connp->out_tx->response_headers, "transfer-encoding");
if (ct != NULL) {
connp->out_tx->response_content_type = bstr_dup_lower(ct->value);
if (connp->out_tx->response_content_type == NULL) return HTP_ERROR;
// Ignore parameters
unsigned char *data = bstr_ptr(connp->out_tx->response_content_type);
size_t len = bstr_len(ct->value);
size_t newlen = 0;
while (newlen < len) {
// TODO Some platforms may do things differently here.
if (htp_is_space(data[newlen]) || (data[newlen] == ';')) {
bstr_adjust_len(connp->out_tx->response_content_type, newlen);
break;
}
newlen++;
}
}
// 2. If a Transfer-Encoding header field (section 14.40) is present and
// indicates that the "chunked" transfer coding has been applied, then
// the length is defined by the chunked encoding (section 3.6).
if ((te != NULL) && (bstr_cmp_c(te->value, "chunked") == 0)) {
// If the T-E header is present we are going to use it.
connp->out_tx->response_transfer_coding = HTP_CODING_CHUNKED;
// We are still going to check for the presence of C-L
if (cl != NULL) {
// This is a violation of the RFC
connp->out_tx->flags |= HTP_REQUEST_SMUGGLING;
}
connp->out_state = htp_connp_RES_BODY_CHUNKED_LENGTH;
connp->out_tx->progress = HTP_RESPONSE_BODY;
}// 3. If a Content-Length header field (section 14.14) is present, its
// value in bytes represents the length of the message-body.
else if (cl != NULL) {
// We know the exact length
connp->out_tx->response_transfer_coding = HTP_CODING_IDENTITY;
// Check for multiple C-L headers
if (cl->flags & HTP_FIELD_REPEATED) {
connp->out_tx->flags |= HTP_REQUEST_SMUGGLING;
}
// Get body length
connp->out_tx->response_content_length = htp_parse_content_length(cl->value);
if (connp->out_tx->response_content_length < 0) {
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0, "Invalid C-L field in response: %d",
connp->out_tx->response_content_length);
return HTP_ERROR;
} else {
connp->out_content_length = connp->out_tx->response_content_length;
connp->out_body_data_left = connp->out_content_length;
if (connp->out_content_length != 0) {
connp->out_state = htp_connp_RES_BODY_IDENTITY_CL_KNOWN;
connp->out_tx->progress = HTP_RESPONSE_BODY;
} else {
connp->out_state = htp_connp_RES_FINALIZE;
}
}
} else {
// 4. If the message uses the media type "multipart/byteranges", which is
// self-delimiting, then that defines the length. This media type MUST
// NOT be used unless the sender knows that the recipient can parse it;
// the presence in a request of a Range header with multiple byte-range
// specifiers implies that the client can parse multipart/byteranges
// responses.
if (ct != NULL) {
// TODO Handle multipart/byteranges
if (bstr_index_of_c_nocase(ct->value, "multipart/byteranges") != -1) {
htp_log(connp, HTP_LOG_MARK, HTP_LOG_ERROR, 0,
"C-T multipart/byteranges in responses not supported");
return HTP_ERROR;
}
}
// 5. By the server closing the connection. (Closing the connection
// cannot be used to indicate the end of a request body, since that
// would leave no possibility for the server to send back a response.)
connp->out_state = htp_connp_RES_BODY_IDENTITY_STREAM_CLOSE;
connp->out_tx->response_transfer_coding = HTP_CODING_IDENTITY;
connp->out_tx->progress = HTP_RESPONSE_BODY;
connp->out_body_data_left = -1;
}
}
// NOTE We do not need to check for short-style HTTP/0.9 requests here because
// that is done earlier, before response line parsing begins
int rc = htp_tx_state_response_headers(connp->out_tx);
if (rc != HTP_OK) return rc;
return HTP_OK;
}
