MPLS ECHO FEC stack change TLV not dissected correctly
Summary
MPLS ECHO FEC stack change TLV not dissected correctly. Brought forward by Pankaj Verma.
Steps to reproduce
Capture MPLS ECHO traffic with these PDU elements. Or load a capture containing them, see attached.
What is the current bug behavior?
Dissection ends in:
Multiprotocol Label Switching Echo
Version: 1
...
Detailed Downstream Mapping
Type: Detailed Downstream Mapping (20)
Length: 40
MTU: 1500
Address Type: IPv4 Numbered (1)
DS Flags: 0x02
Downstream IP Address: 210.1.1.1 (210.1.1.1)
Downstream Interface Address: 210.1.1.1 (210.1.1.1)
Return Code: 0
Return Subcode: 0
Subtlv Length: 24
[Expert Info (Error/Malformed): Invalid Sub-tlv Length (claimed 24, found 8)]
[Invalid Sub-tlv Length (claimed 24, found 8)]
[Severity level: Error]
[Group: Malformed]
Stack change sub-TLV
Operation Type: Pop (2)
Address Type: IPv4 (1)
FEC tlv Length: 0
Reserved: 0
Remote Peer IP Address: 6.6.6.6 (6.6.6.6)
From attached multiple_fec_stack_change_tlv.pcap
What is the expected correct behavior?
Dissections ends in
Multiprotocol Label Switching Echo
Version: 1
...
Detailed Downstream Mapping
Type: Detailed Downstream Mapping (20)
Length: 40
MTU: 1500
Address Type: IPv4 Numbered (1)
DS Flags: 0x02
Downstream IP Address: 210.1.1.1 (210.1.1.1)
Downstream Interface Address: 210.1.1.1 (210.1.1.1)
Return Code: 0
Return Subcode: 0
Subtlv Length: 24
Stack change sub-TLV
Operation Type: Pop (2)
Address Type: IPv4 (1)
FEC tlv Length: 0
Reserved: 0
Remote Peer IP Address: 6.6.6.6 (6.6.6.6)
Stack change sub-TLV
Operation Type: Pop (2)
Address Type: IPv4 (1)
FEC tlv Length: 0
Reserved: 0
Remote Peer IP Address: 7.7.7.7 (7.7.7.7)
From attached multiple_fec_stack_change_tlv.pcap
Sample capture file
fec_stack_change_with_target_fec_tlv.pcap multiple_fec_stack_change_tlv.pcap
Relevant logs and/or screenshots
See above
Build information
Version 3.6.0 (v3.6.0-0-g3a34e44d), as reported by Pankaj Verma.