The Babel IETF working group is in the process of specifying an extension to the Babel protocol that adds HMAC authentication of messages. The current draft proposal is available as draft-do-babel-hmac-00: https://tools.ietf.org/html/draft-do-babel-hmac-00 This patch adds an implementation of this draft to Babel in Bird. The draft is a way from being finalised, so it is premature to merge the code. Instead, this should be seen as a call for feedback on both the implementation and the draft specification. The proof of concept implementation of HMAC for babeld is available in the hmac-challenge branch of this repository: https://github.com/wkolod/babeld With this patch, Bird can successfully exchange HMAC-authenticated messages with babeld in the above repo. -Toke --- Toke Høiland-Jørgensen (2): babel: Define helper macro for looping through TLVs babel: Add HMAC support proto/babel/babel.c | 80 +++++++++ proto/babel/babel.h | 58 ++++++ proto/babel/config.Y | 34 ++++ proto/babel/packets.c | 439 +++++++++++++++++++++++++++++++++++++++++++++---- 4 files changed, 567 insertions(+), 44 deletions(-)