smc-clc

smc-clc is a command line tool for capturing SMC CLC traffic from a network interface and parsing the SMC CLC handshake messages. The CLC handshake is part of the SMC protocol and is used to establish SMC connections between communication partners.

Installation

You can download and install smc-clc with its dependencies to your GOPATH or GOBIN with the go tool:

$ go install github.com/hwipl/smc-clc/cmd/smc-clc

Usage

You can run smc-clc with the following command line arguments:

  -f file
        read packets from a pcap file and set it to file
  -http address
        use http server output and listen on address (e.g.: :8000 or
        127.0.0.1:8080)
  -i interface
        read packets from a network interface (default) and set it to interface
  -pcap-filter filter
        set pcap packet filter to filter (e.g.: "not port 22")
  -pcap-maxpkts number
        set maximum packets to capture to number (may require pcap-timeout
        argument)
  -pcap-maxtime seconds
        set maximum capturing time to seconds (may require pcap-timeout
        argument)
  -pcap-promisc
        set network interface to promiscuous mode (default true)
  -pcap-snaplen bytes
        set pcap snaplen to bytes (default 2048)
  -pcap-timeout milliseconds
        set pcap timeout to milliseconds
  -show-hex
        show hex dumps of messages
  -show-reserved
        show reserved message fields
  -show-timestamps
        show timestamps of messages (default true)

Examples

You can specify the network interface with the command line argument -i. Make sure your user has the permission to capture traffic on the network interface. For example, you can capture packets on the loopback interface with the following command as user root:

# smc-clc -i lo

Alternatively, you can read packets from a pcap file with the command line argument -f. For example you can read the packets from pcap file dump.pcap with the following command:

$ smc-clc -f dump.pcap

The regular output of, for example, a SMC handshake over IPv4 on the loopback interface looks like this:

$ sudo ./smc-clc -i lo
Starting to listen on interface lo.
16:17:14.341225 127.0.0.1:60294 -> 127.0.0.1:50000: Proposal: Eyecatcher: SMC-R,
Type: 1 (Proposal), Length: 52, Version: 1, Flag: 0, Path: SMC-R,
Peer ID: 45472@98:03:9b:ab:cd:ef, SMC-R GID: fe80::9a03:9bff:feab:cdef,
RoCE MAC: 98:03:9b:ab:cd:ef, IP Area Offset: 0, SMC-D GID: 0,
IPv4 Prefix: 127.0.0.0/8, IPv6 Prefix Count: 0, Trailer: SMC-R
16:17:14.342858 127.0.0.1:50000 -> 127.0.0.1:60294: Accept: Eyecatcher: SMC-R,
Type: 2 (Accept), Length: 68, Version: 1, First Contact: 1, Path: SMC-R,
Peer ID: 45472@98:03:9b:ab:cd:ef, SMC-R GID: fe80::9a03:9bff:feab:cdef,
RoCE MAC: 98:03:9b:ab:cd:ef, QP Number: 228, RMB RKey: 5501, RMBE Index: 1,
RMBE Alert Token: 5, RMBE Size: 2 (65536), QP MTU: 3 (1024),
RMB Virtual Address: 0xf0a60000, Packet Sequence Number: 7534078,
Trailer: SMC-R
16:17:14.343078 127.0.0.1:60294 -> 127.0.0.1:50000: Confirm: Eyecatcher: SMC-R,
Type: 3 (Confirm), Length: 68, Version: 1, Flag: 0, Path: SMC-R,
Peer ID: 45472@98:03:9b:ab:cd:ef, SMC-R GID: fe80::9a03:9bff:feab:cdef,
RoCE MAC: 98:03:9b:ab:cd:ef, QP Number: 229, RMB RKey: 6271, RMBE Index: 1,
RMBE Alert Token: 6, RMBE Size: 2 (65536), QP MTU: 3 (1024),
RMB Virtual Address: 0xf0a40000, Packet Sequence Number: 887204,
Trailer: SMC-R

You can enable hex dumps in the output with the command line argument -show-hex. The output of the same SMC handshake as above with enabled hex dumps of the messages looks like this:

$ sudo ./smc-clc -i lo -show-hex
Starting to listen on interface lo.
16:17:14.341225 127.0.0.1:60294 -> 127.0.0.1:50000: Proposal: Eyecatcher: SMC-R,
Type: 1 (Proposal), Length: 52, Version: 1, Flag: 0, Path: SMC-R,
Peer ID: 45472@98:03:9b:ab:cd:ef, SMC-R GID: fe80::9a03:9bff:feab:cdef,
RoCE MAC: 98:03:9b:ab:cd:ef, IP Area Offset: 0, SMC-D GID: 0,
IPv4 Prefix: 127.0.0.0/8, IPv6 Prefix Count: 0, Trailer: SMC-R
00000000  e2 d4 c3 d9 01 00 34 10  b1 a0 98 03 9b ab cd ef  |......4.........|
00000010  fe 80 00 00 00 00 00 00  9a 03 9b ff fe ab cd ef  |................|
00000020  98 03 9b ab cd ef 00 00  7f 00 00 00 08 00 00 00  |................|
00000030  e2 d4 c3 d9                                       |....|
16:17:14.342858 127.0.0.1:50000 -> 127.0.0.1:60294: Accept: Eyecatcher: SMC-R,
Type: 2 (Accept), Length: 68, Version: 1, First Contact: 1, Path: SMC-R,
Peer ID: 45472@98:03:9b:ab:cd:ef, SMC-R GID: fe80::9a03:9bff:feab:cdef,
RoCE MAC: 98:03:9b:ab:cd:ef, QP Number: 228, RMB RKey: 5501, RMBE Index: 1,
RMBE Alert Token: 5, RMBE Size: 2 (65536), QP MTU: 3 (1024),
RMB Virtual Address: 0xf0a60000, Packet Sequence Number: 7534078,
Trailer: SMC-R
00000000  e2 d4 c3 d9 02 00 44 18  b1 a0 98 03 9b ab cd ef  |......D.........|
00000010  fe 80 00 00 00 00 00 00  9a 03 9b ff fe ab cd ef  |................|
00000020  98 03 9b ab cd ef 00 00  e4 00 00 15 7d 01 00 00  |............}...|
00000030  00 05 23 00 00 00 00 00  f0 a6 00 00 00 72 f5 fe  |..#..........r..|
00000040  e2 d4 c3 d9                                       |....|
16:17:14.343078 127.0.0.1:60294 -> 127.0.0.1:50000: Confirm: Eyecatcher: SMC-R,
Type: 3 (Confirm), Length: 68, Version: 1, Flag: 0, Path: SMC-R,
Peer ID: 45472@98:03:9b:ab:cd:ef, SMC-R GID: fe80::9a03:9bff:feab:cdef,
RoCE MAC: 98:03:9b:ab:cd:ef, QP Number: 229, RMB RKey: 6271, RMBE Index: 1,
RMBE Alert Token: 6, RMBE Size: 2 (65536), QP MTU: 3 (1024),
RMB Virtual Address: 0xf0a40000, Packet Sequence Number: 887204,
Trailer: SMC-R
00000000  e2 d4 c3 d9 03 00 44 10  b1 a0 98 03 9b ab cd ef  |......D.........|
00000010  fe 80 00 00 00 00 00 00  9a 03 9b ff fe ab cd ef  |................|
00000020  98 03 9b ab cd ef 00 00  e5 00 00 18 7f 01 00 00  |................|
00000030  00 06 23 00 00 00 00 00  f0 a4 00 00 00 0d 89 a4  |..#.............|
00000040  e2 d4 c3 d9                                       |....|