diff options
| author | Vladimir Gavrilov <105977161+0xA50C1A1@users.noreply.github.com> | 2023-11-27 16:37:48 +0300 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2023-11-27 14:37:48 +0100 |
| commit | 3763c702f0f6ae0aaff3a51dc52b4ec48a0d15fb (patch) | |
| tree | 6013cf81b0880901970e3ad8f436a2c94bf50d86 /src/lib/protocols/s7comm.c | |
| parent | 0b6e261523f6d8ff66ae711922fc266bb6baa07c (diff) | |
Rework S7Comm dissector; add S7Comm Plus support (#2165)
* Rework S7Comm dissector; add S7Comm Plus support
* Cleanup s7comm.c
* Improve S7Comm Plus detection
* s7comm/s7commplus: faster detection
---------
Co-authored-by: 0xA50C1A1 <mage.wizard88@gmail.com>
Co-authored-by: Nardi Ivan <nardi.ivan@gmail.com>
Diffstat (limited to 'src/lib/protocols/s7comm.c')
| -rw-r--r-- | src/lib/protocols/s7comm.c | 83 |
1 files changed, 57 insertions, 26 deletions
diff --git a/src/lib/protocols/s7comm.c b/src/lib/protocols/s7comm.c index ce3d47218..45ecfd3f5 100644 --- a/src/lib/protocols/s7comm.c +++ b/src/lib/protocols/s7comm.c @@ -1,8 +1,9 @@ /*
* s7comm.c
*
- * Copyright (C) 2011-22 - ntop.org
- *
+ * Copyright (C) 2023 - ntop.org
+ * Copyright (C) 2023 - V.G <jacendi@protonmail.com>
+ *
* This file is part of nDPI, an open source deep packet inspection
* library based on the OpenDPI and PACE technology by ipoque GmbH
*
@@ -20,40 +21,70 @@ * along with nDPI. If not, see <http://www.gnu.org/licenses/>.
*
*/
+
#include "ndpi_protocol_ids.h"
+
#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_S7COMM
+
#include "ndpi_api.h"
#include "ndpi_private.h"
-static void ndpi_search_s7comm_tcp(struct ndpi_detection_module_struct *ndpi_struct,
- struct ndpi_flow_struct *flow) {
- struct ndpi_packet_struct *packet = &ndpi_struct->packet;
- NDPI_LOG_DBG(ndpi_struct, "search S7\n");
- u_int16_t s7comm_port = htons(102);
- if(packet->tcp) {
-
- if((packet->payload_packet_len >= 2) && (packet->payload[0]==0x03)&&(packet->payload[1]==0x00)&&((packet->tcp->dest == s7comm_port) || (packet->tcp->source == s7comm_port))) {
- NDPI_LOG_INFO(ndpi_struct, "found S7\n");
- ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_S7COMM, NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
-
- return;
-
+#define TPKT_PORT 102
+#define S7COMM_MAGIC_BYTE 0x32
+#define S7COMM_PLUS_MAGIC_BYTE 0x72
+
+static void ndpi_search_s7comm(struct ndpi_detection_module_struct *ndpi_struct,
+ struct ndpi_flow_struct *flow)
+{
+ struct ndpi_packet_struct const * const packet = &ndpi_struct->packet;
+
+ NDPI_LOG_DBG(ndpi_struct, "search S7comm\n");
+
+ if (packet->tcp) {
+ u_int16_t sport = ntohs(packet->tcp->source);
+ u_int16_t dport = ntohs(packet->tcp->dest);
+
+ /* S7Comm uses a default TPKT port 102 */
+ if (((sport == TPKT_PORT) || (dport == TPKT_PORT)) &&
+ (packet->payload_packet_len > 17)) /* TPKT+COTP+S7Comm header lengths */
+ {
+ if ((packet->payload[0] == 0x03) && (packet->payload[1] == 0x00) &&
+ (ntohs(get_u_int16_t(packet->payload, 2)) == packet->payload_packet_len))
+ {
+ if (packet->payload[7] == S7COMM_PLUS_MAGIC_BYTE) {
+ const u_int16_t trail_byte_offset = packet->payload_packet_len - 4;
+ if (packet->payload[trail_byte_offset] == S7COMM_PLUS_MAGIC_BYTE)
+ {
+ NDPI_LOG_INFO(ndpi_struct, "found S7CommPlus\n");
+ ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_S7COMM_PLUS,
+ NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
+ return;
+ }
+ } else if (packet->payload[7] == S7COMM_MAGIC_BYTE) {
+ if (((packet->payload[8] <= 0x03) || (packet->payload[8] == 0x07)) &&
+ (get_u_int16_t(packet->payload, 9) == 0))
+ {
+ NDPI_LOG_INFO(ndpi_struct, "found S7Comm\n");
+ ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_S7COMM,
+ NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
+ return;
+ }
+ }
+ return;
+ }
}
}
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
-
}
-void init_s7comm_dissector(struct ndpi_detection_module_struct *ndpi_struct,
- u_int32_t *id) {
-
- ndpi_set_bitmask_protocol_detection("S7COMM", ndpi_struct, *id,
- NDPI_PROTOCOL_S7COMM,
- ndpi_search_s7comm_tcp,
- NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
- SAVE_DETECTION_BITMASK_AS_UNKNOWN,
- ADD_TO_DETECTION_BITMASK);
+void init_s7comm_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id)
+{
+ ndpi_set_bitmask_protocol_detection("S7Comm", ndpi_struct, *id,
+ NDPI_PROTOCOL_S7COMM,
+ ndpi_search_s7comm,
+ NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
+ SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+ ADD_TO_DETECTION_BITMASK);
*id += 1;
}
-
|