http: Use libhtp-rs.

http: Use libhtp-rs.

Ticket: #2696

There are a lot of changes here, which are described below.

In general these changes are renaming constants to conform to the
libhtp-rs versions (which are generated by cbindgen); making all htp
types opaque and changing struct->member references to
htp_struct_member() function calls; and a handful of changes to offload
functionality onto libhtp-rs from suricata, such as URI normalization
and transaction cleanup.

Functions introduced to handle opaque htp_tx_t:
- tx->parsed_uri => htp_tx_parsed_uri(tx)
- tx->parsed_uri->path => htp_uri_path(htp_tx_parsed_uri(tx)
- tx->parsed_uri->hostname => htp_uri_hostname(htp_tx_parsed_uri(tx))
- htp_tx_get_user_data() => htp_tx_user_data(tx)
- htp_tx_is_http_2_upgrade(tx) convenience function introduced to detect response status 101
  and “Upgrade: h2c" header.

Functions introduced to handle opaque htp_tx_data_t:
- d->len => htp_tx_data_len()
- d->data => htp_tx_data_data()
- htp_tx_data_tx(data) function to get the htp_tx_t from the htp_tx_data_t
- htp_tx_data_is_empty(data) convenience function introduced to test if the data is empty.

Other changes:

Build libhtp-rs as a crate inside rust. Update autoconf to no longer
use libhtp as an external dependency. Remove HAVE_HTP feature defines
since they are no longer needed.

Make function arguments and return values const where possible

htp_tx_destroy(tx) will now free an incomplete transaction

htp_time_t replaced with standard struct timeval

Callbacks from libhtp now provide the htp_connp_t and the htp_tx_data_t
as separate arguments. This means the connection parser is no longer
fetched from the transaction inside callbacks.

SCHTPGenerateNormalizedUri() functionality moved inside libhtp-rs, which
now provides normalized URI values.
The normalized URI is available with accessor function: htp_tx_normalized_uri()
Configuration settings added to control the behaviour of the URI normalization:
- htp_config_set_normalized_uri_include_all()
- htp_config_set_plusspace_decode()
- htp_config_set_convert_lowercase()
- htp_config_set_double_decode_normalized_query()
- htp_config_set_double_decode_normalized_path()
- htp_config_set_backslash_convert_slashes()
- htp_config_set_bestfit_replacement_byte()
- htp_config_set_convert_lowercase()
- htp_config_set_nul_encoded_terminates()
- htp_config_set_nul_raw_terminates()
- htp_config_set_path_separators_compress()
- htp_config_set_path_separators_decode()
- htp_config_set_u_encoding_decode()
- htp_config_set_url_encoding_invalid_handling()
- htp_config_set_utf8_convert_bestfit()
- htp_config_set_normalized_uri_include_all()
- htp_config_set_plusspace_decode()
Constants related to configuring uri normalization:
- HTP_URL_DECODE_PRESERVE_PERCENT => HTP_URL_ENCODING_HANDLING_PRESERVE_PERCENT
- HTP_URL_DECODE_REMOVE_PERCENT => HTP_URL_ENCODING_HANDLING_REMOVE_PERCENT
- HTP_URL_DECODE_PROCESS_INVALID => HTP_URL_ENCODING_HANDLING_PROCESS_INVALID

htp_config_set_field_limits(soft_limit, hard_limit) changed to
htp_config_set_field_limit(limit) because libhtp didn't implement soft
limits.

libhtp logging API updated to provide HTP_LOG_CODE constants along with
the message. This eliminates the need to perform string matching on
message text to map log messages to HTTP_DECODER_EVENT values, and the
HTP_LOG_CODE values can be used directly. In support of this,
HTP_DECODER_EVENT values are mapped to their corresponding HTP_LOG_CODE
values.

New log events to describe additional anomalies:
HTP_LOG_CODE_REQUEST_TOO_MANY_LZMA_LAYERS
HTP_LOG_CODE_RESPONSE_TOO_MANY_LZMA_LAYERS
HTP_LOG_CODE_PROTOCOL_CONTAINS_EXTRA_DATA
HTP_LOG_CODE_CONTENT_LENGTH_EXTRA_DATA_START
HTP_LOG_CODE_CONTENT_LENGTH_EXTRA_DATA_END
HTP_LOG_CODE_SWITCHING_PROTO_WITH_CONTENT_LENGTH
HTP_LOG_CODE_DEFORMED_EOL
HTP_LOG_CODE_PARSER_STATE_ERROR
HTP_LOG_CODE_MISSING_OUTBOUND_TRANSACTION_DATA
HTP_LOG_CODE_MISSING_INBOUND_TRANSACTION_DATA
HTP_LOG_CODE_ZERO_LENGTH_DATA_CHUNKS
HTP_LOG_CODE_REQUEST_LINE_UNKNOWN_METHOD
HTP_LOG_CODE_REQUEST_LINE_UNKNOWN_METHOD_NO_PROTOCOL
HTP_LOG_CODE_REQUEST_LINE_UNKNOWN_METHOD_INVALID_PROTOCOL
HTP_LOG_CODE_REQUEST_LINE_NO_PROTOCOL
HTP_LOG_CODE_RESPONSE_LINE_INVALID_PROTOCOL
HTP_LOG_CODE_RESPONSE_LINE_INVALID_RESPONSE_STATUS
HTP_LOG_CODE_RESPONSE_BODY_INTERNAL_ERROR
HTP_LOG_CODE_REQUEST_BODY_DATA_CALLBACK_ERROR
HTP_LOG_CODE_RESPONSE_INVALID_EMPTY_NAME
HTP_LOG_CODE_REQUEST_INVALID_EMPTY_NAME
HTP_LOG_CODE_RESPONSE_INVALID_LWS_AFTER_NAME
HTP_LOG_CODE_RESPONSE_HEADER_NAME_NOT_TOKEN
HTP_LOG_CODE_REQUEST_INVALID_LWS_AFTER_NAME
HTP_LOG_CODE_LZMA_DECOMPRESSION_DISABLED
HTP_LOG_CODE_CONNECTION_ALREADY_OPEN
HTP_LOG_CODE_COMPRESSION_BOMB_DOUBLE_LZMA
HTP_LOG_CODE_INVALID_CONTENT_ENCODING
HTP_LOG_CODE_INVALID_GAP
HTP_LOG_CODE_ERROR

The new htp_log API supports consuming log messages more easily than
walking a list and tracking the current offset. Internally, libhtp-rs
now provides log messages as a queue of htp_log_t, which means the
application can simply call htp_conn_next_log() to fetch the next log
message until the queue is empty. Once the application is done with a
log message, they can call htp_log_free() to dispose of it.

Functions supporting htp_log_t:
htp_conn_next_log(conn) - Get the next log message
htp_log_message(log) - To get the text of the message
htp_log_code(log) - To get the HTP_LOG_CODE value
htp_log_free(log) - To free the htp_log_t