Last Modified: Sep 13, 2023
Affected Product(s):
BIG-IP TMOS
Known Affected Versions:
12.1.1, 12.1.2, 12.1.3, 12.1.3.1, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1
Fixed In:
13.1.0, 12.1.3.2
Opened: Mar 23, 2017 Severity: 3-Major Related Article:
K88825548
During negotiations that use CREATE_CHILD_SA, IKEv2 will fail to send a KE in the payload when PFS (perfect forward security) is used in config. Rekey in IKEv2 does not negotiate new keys; the PFS value in phase1-perfect-forward-secrecy is used in the first exchange, then this first key is re-used in later rekey negotiation. Vendor interop problems exist when PFS is required by the other peer.
PFS settings apply only to first negotiation and not to subsequent SA rekeys. PFS is therefore absent. When the BIG-IP enters CREATE_CHILD_SA with a third party IPsec peer, negotiation will fail if the peer requires PFS. Under the same conditions, BIG-IP to BIG-IP tunnels will not fail.
Define phase1-perfect-forward-secrecy with value other than none. After IPsec SAs expire or are manually deleted, the CREATE_CHILD_SA phase to negotiate new keys has no KEi payload from the BIG-IP Initiator and so no new encryption key.
To resolve vendor interop problems, disable PFS in the IPsec policy of both peers.
When phase1-perfect-forward-secrecy is configured with a value other than none, the BIG-IP will now perform PFS negotiation correctly. Now rekey with CREATE_CHILD_SA generates a new key using the same DH Group as the first exchange that creates the first SA. Note: In the ipsec-policy configuration object, the ike-phase2-perfect-forward-secrecy option is relevant only to IKEv1 and has no influence on IKEv2 PFS rekeying.