/*
* memcached.c
*
* Copyright (C) 2009-11 - ipoque GmbH
* Copyright (C) 2011-22 - ntop.org
* Copyright (C) 2018 - eGloo Incorporated
*
* This file is part of nDPI, an open source deep packet inspection
* library based on the OpenDPI and PACE technology by ipoque GmbH
*
* nDPI is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* nDPI is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with nDPI. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "ndpi_protocol_ids.h"
#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_MEMCACHED
#include "ndpi_api.h"
#include "ndpi_private.h"
#define MCDC_SET "set "
#define MCDC_SET_LEN (sizeof(MCDC_SET) - 1)
#define MCDC_ADD "add "
#define MCDC_ADD_LEN (sizeof(MCDC_ADD) - 1)
#define MCDC_REPLACE "replace "
#define MCDC_REPLACE_LEN (sizeof(MCDC_REPLACE) - 1)
#define MCDC_APPEND "append "
#define MCDC_APPEND_LEN (sizeof(MCDC_APPEND) - 1)
#define MCDC_PREPEND "prepend "
#define MCDC_PREPEND_LEN (sizeof(MCDC_PREPEND) - 1)
#define MCDC_CAS "cas "
#define MCDC_CAS_LEN (sizeof(MCDC_CAS) - 1)
#define MCDC_GET "get "
#define MCDC_GET_LEN (sizeof(MCDC_GET) - 1)
#define MCDC_GETS "gets "
#define MCDC_GETS_LEN (sizeof(MCDC_GETS) - 1)
#define MCDC_DELETE "delete "
#define MCDC_DELETE_LEN (sizeof(MCDC_DELETE) - 1)
#define MCDC_INCR "incr "
#define MCDC_INCR_LEN (sizeof(MCDC_INCR) - 1)
#define MCDC_DECR "decr "
#define MCDC_DECR_LEN (sizeof(MCDC_DECR) - 1)
#define MCDC_TOUCH "touch "
#define MCDC_TOUCH_LEN (sizeof(MCDC_TOUCH) - 1)
#define MCDC_GAT "gat "
#define MCDC_GAT_LEN (sizeof(MCDC_GAT) - 1)
#define MCDC_GATS "gats "
#define MCDC_GATS_LEN (sizeof(MCDC_GATS) - 1)
#define MCDC_STATS "stats"
#define MCDC_STATS_LEN (sizeof(MCDC_STATS) - 1)
#define MCDR_ERROR "ERROR\r\n"
#define MCDR_ERROR_LEN (sizeof(MCDR_ERROR) - 1)
#define MCDR_CLIENT_ERROR "CLIENT_ERROR "
#define MCDR_CLIENT_ERROR_LEN (sizeof(MCDR_CLIENT_ERROR) - 1)
#define MCDR_SERVER_ERROR "SERVER_ERROR "
#define MCDR_SERVER_ERROR_LEN (sizeof(MCDR_SERVER_ERROR) - 1)
#define MCDR_STORED "STORED\r\n"
#define MCDR_STORED_LEN (sizeof(MCDR_STORED) - 1)
#define MCDR_NOT_STORED "NOT_STORED\r\n"
#define MCDR_NOT_STORED_LEN (sizeof(MCDR_NOT_STORED) - 1)
#define MCDR_EXISTS "EXISTS\r\n"
#define MCDR_EXISTS_LEN (sizeof(MCDR_EXISTS) - 1)
#define MCDR_NOT_FOUND "NOT_FOUND\r\n"
#define MCDR_NOT_FOUND_LEN (sizeof(MCDR_NOT_FOUND) - 1)
#define MCDR_END "END\r\n"
#define MCDR_END_LEN (sizeof(MCDR_END) - 1)
#define MCDR_DELETED "DELETED\r\n"
#define MCDR_DELETED_LEN (sizeof(MCDR_DELETED) - 1)
#define MCDR_TOUCHED "TOUCHED\r\n"
#define MCDR_TOUCHED_LEN (sizeof(MCDR_TOUCHED) - 1)
#define MCDR_STAT "STAT "
#define MCDR_STAT_LEN (sizeof(MCDR_STAT) - 1)
#define MEMCACHED_UDP_HDR_LEN 8
#define MEMCACHED_MIN_LEN MCDR_END_LEN
#define MEMCACHED_MIN_UDP_LEN (MEMCACHED_MIN_LEN + MEMCACHED_UDP_HDR_LEN)
#define MEMCACHED_MIN_MATCH 2 /* Minimum number of command/responses required */
#define MEMCACHED_MATCH(cr) (cr ## _LEN > length || memcmp(offset, cr, cr ## _LEN))
static void ndpi_int_memcached_add_connection(struct ndpi_detection_module_struct
*ndpi_struct, struct ndpi_flow_struct *flow)
{
NDPI_LOG_INFO(ndpi_struct, "found memcached\n");
ndpi_set_detected_protocol(ndpi_struct, flow,
NDPI_PROTOCOL_MEMCACHED, NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
}
static void ndpi_search_memcached(struct ndpi_detection_module_struct *ndpi_struct,
struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &ndpi_struct->packet;
const u_int8_t *offset = packet->payload;
u_int16_t length = packet->payload_packet_len;
u_int8_t *matches = NULL;
NDPI_LOG_DBG(ndpi_struct, "search memcached\n");
if (packet->tcp != NULL) {
if (packet->payload_packet_len < MEMCACHED_MIN_LEN) {
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
return;
}
matches = &flow->l4.tcp.memcached_matches;
}
else if (packet->udp != NULL) {
if (packet->payload_packet_len < MEMCACHED_MIN_UDP_LEN) {
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
return;
}
if ((offset[4] == 0x00 && offset[5] == 0x00) ||
offset[6] != 0x00 || offset[7] != 0x00) {
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
return;
}
offset += MEMCACHED_UDP_HDR_LEN;
length -= MEMCACHED_UDP_HDR_LEN;
matches = &flow->l4.udp.memcached_matches;
}
/* grep MCD memcached.c |\
* egrep -v '(LEN|MATCH)' |\
* sed -e 's/^#define //g' |\
* awk '{ printf "else if (! MEMCACHED_MATCH(%s)) *matches += 1;\n",$1 }' */
if (! MEMCACHED_MATCH(MCDC_SET)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_ADD)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_REPLACE)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_APPEND)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_PREPEND)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_CAS)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_GET)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_GETS)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_DELETE)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_INCR)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_DECR)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_TOUCH)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_GAT)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_GATS)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDC_STATS)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_ERROR)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_CLIENT_ERROR)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_SERVER_ERROR)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_STORED)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_NOT_STORED)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_EXISTS)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_NOT_FOUND)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_END)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_DELETED)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_TOUCHED)) *matches += 1;
else if (! MEMCACHED_MATCH(MCDR_STAT)) *matches += 1;
if (*matches >= MEMCACHED_MIN_MATCH)
ndpi_int_memcached_add_connection(ndpi_struct, flow);
else if(flow->packet_counter > 5)
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}
void init_memcached_dissector(
struct ndpi_detection_module_struct *ndpi_struct,
u_int32_t *id)
{
ndpi_set_bitmask_protocol_detection("MEMCACHED",
ndpi_struct, *id,
NDPI_PROTOCOL_MEMCACHED,
ndpi_search_memcached,
NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_OR_UDP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
SAVE_DETECTION_BITMASK_AS_UNKNOWN,
ADD_TO_DETECTION_BITMASK);
*id += 1;
}