Markdown Version | Session Recording

Session Date/Time: 19 Mar 2024 05:30

ipsecme

Summary

The ipsecme working group meeting covered several draft proposals, including ML-KEM integration with IKEv2, an ESP echo protocol (ESP Ping), sharing a single IPsec tunnel for multiple VPNs, disabling anti-replay with ESN, the SM2/SM3/SM4 cryptographic algorithms and fragmentation avoidance using LMAP. Discussions focused on the technical details of each proposal, potential issues, and whether they should be adopted as working group drafts.

Key Discussion Points

• ML-KEM:
  • Should ML-KEM 512 be assigned a code point for use in IKE init for pure post-quantum key exchange?
  • Should this be a working group draft or obtain code points via expert review?
  • Suggestion to consider a more generic "how to use post-quantum KEM in IKEv2" draft.
  • Strong support for adopting the draft and publishing it, even if short.
• ESP Ping:
  • Initial draft proposed reserved SPIs for echo requests/responses.
  • Discussion of using production SPIs for troubleshooting, but concerns about differentiating echo packets from dummy packets when using next header 59.
  • Security considerations: Preventing downgrade attacks and avoiding denial-of-service amplification.
  • How to determine if the remote site supports ESP Ping.
  • Concerns about false positives and how to determine blocked traffic vs. unsupported endpoints.
  • Alternative solution proposed involving an IKE message requesting a dummy IPsec packet.
  • Using existing notify mechanisms to signal capabilities.
• Multi-VPN IPsec Tunnel Sharing:
  • Problem of IPsec tunnel scalability in 3GPP networks with RAN sharing.
  • Proposed solution to share a single IPsec tunnel for multiple VPNs by adding VPN-related information to traffic selectors and ESP/AH headers.
  • Alternative solutions discussed: splitting the SPI field, using a unified flow ID, or using IPV6
  • Concerns regarding the need for transporting VPN IDs over the network in ESP packets.
• Anti-Replay/ESN:
  • Discussion of disabling anti-replay protection and the impact on Extended Sequence Numbers (ESN).
  • Should ESN be unbinded from antireplay?
  • Notification methods.
• SM2/SM3/SM4:
  • Introduction of Chinese national standard cryptographic algorithms to IPsec.
  • Request to add several new items to register, type transforms and methods to the current IKE definition.
  • Recommendation to follow the ISE (Independent Submissions Editor) process.
  • Questioning the necessity of keeping CBC mode.
• LMAP:
  • Use of LMAP to avoid debris assembly operations.
  • PTB (Packet Too Big) extension discussed.

Decisions and Action Items

• ML-KEM: Panos to consider the suggestion to have a generic "how to use post-quantum KEM in IKEv2" draft.
• ESP Ping: Move discussion to the mailing list.
• Multi-VPN IPsec Tunnel Sharing: Bring discussion back to the mailing list.
• Anti-Replay/ESN: Bring discussion back to the mailing list.
• SM2/SM3/SM4: Work toward submission to the ISE (Independent Submissions Editor) process.
• DSCP: Chair to discuss with AD Deb Cooley whether DSCP is in scope.

Next Steps

• Continue discussions on the mailing list for ESP Ping, Multi-VPN IPsec Tunnel Sharing and Anti-Replay/ESN.
• Consider the generic post-quantum KEM document for ML-KEM.
• Submit SM2/SM3/SM4 to the ISE (Independent Submissions Editor) process.
• Discuss the charter and adoption for DSCP with the AD.