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/*
* syslog.c
*
* Copyright (C) 2009-2011 by ipoque GmbH
* Copyright (C) 2011-15 - ntop.org
*
* 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_protocols.h"
#ifdef NDPI_PROTOCOL_SYSLOG
static void ndpi_int_syslog_add_connection(struct ndpi_detection_module_struct
*ndpi_struct, struct ndpi_flow_struct *flow)
{
ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_SYSLOG, NDPI_PROTOCOL_UNKNOWN);
}
void ndpi_search_syslog(struct ndpi_detection_module_struct
*ndpi_struct, struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
// struct ndpi_id_struct *src=ndpi_struct->src;
// struct ndpi_id_struct *dst=ndpi_struct->dst;
u_int8_t i;
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "search syslog\n");
if (packet->payload_packet_len > 20 && packet->payload_packet_len <= 1024 && packet->payload[0] == '<') {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "checked len>20 and <1024 and first symbol=<.\n");
i = 1;
for (;;) {
if (packet->payload[i] < '0' || packet->payload[i] > '9' || i++ > 3) {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG,
"read symbols while the symbol is a number.\n");
break;
}
}
if (packet->payload[i++] != '>') {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "there is no > following the number.\n");
NDPI_ADD_PROTOCOL_TO_BITMASK(flow->excluded_protocol_bitmask, NDPI_PROTOCOL_SYSLOG);
return;
} else {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "a > following the number.\n");
}
if (packet->payload[i] == 0x20) {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "a blank following the >: increment i.\n");
i++;
} else {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "no blank following the >: do nothing.\n");
}
/* check for "last message repeated" */
if (i + sizeof("last message") - 1 <= packet->payload_packet_len &&
memcmp(packet->payload + i, "last message", sizeof("last message") - 1) == 0) {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "found syslog by 'last message' string.\n");
ndpi_int_syslog_add_connection(ndpi_struct, flow);
return;
} else if (i + sizeof("snort: ") - 1 <= packet->payload_packet_len &&
memcmp(packet->payload + i, "snort: ", sizeof("snort: ") - 1) == 0) {
/* snort events */
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "found syslog by 'snort: ' string.\n");
ndpi_int_syslog_add_connection(ndpi_struct, flow);
return;
}
if (memcmp(&packet->payload[i], "Jan", 3) != 0
&& memcmp(&packet->payload[i], "Feb", 3) != 0
&& memcmp(&packet->payload[i], "Mar", 3) != 0
&& memcmp(&packet->payload[i], "Apr", 3) != 0
&& memcmp(&packet->payload[i], "May", 3) != 0
&& memcmp(&packet->payload[i], "Jun", 3) != 0
&& memcmp(&packet->payload[i], "Jul", 3) != 0
&& memcmp(&packet->payload[i], "Aug", 3) != 0
&& memcmp(&packet->payload[i], "Sep", 3) != 0
&& memcmp(&packet->payload[i], "Oct", 3) != 0
&& memcmp(&packet->payload[i], "Nov", 3) != 0 && memcmp(&packet->payload[i], "Dec", 3) != 0) {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG,
"no month-shortname following: syslog excluded.\n");
NDPI_ADD_PROTOCOL_TO_BITMASK(flow->excluded_protocol_bitmask, NDPI_PROTOCOL_SYSLOG);
return;
} else {
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG,
"a month-shortname following: syslog detected.\n");
ndpi_int_syslog_add_connection(ndpi_struct, flow);
return;
}
}
NDPI_LOG(NDPI_PROTOCOL_SYSLOG, ndpi_struct, NDPI_LOG_DEBUG, "no syslog detected.\n");
NDPI_ADD_PROTOCOL_TO_BITMASK(flow->excluded_protocol_bitmask, NDPI_PROTOCOL_SYSLOG);
}
void init_syslog_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
ndpi_set_bitmask_protocol_detection("SYSLOG", ndpi_struct, detection_bitmask, *id,
NDPI_PROTOCOL_SYSLOG,
ndpi_search_syslog,
NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_OR_UDP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
SAVE_DETECTION_BITMASK_AS_UNKNOWN,
ADD_TO_DETECTION_BITMASK);
*id += 1;
}
#endif
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