Red Hat Bugzilla – Bug 485933
Use CONFIG_SCTP_HMAC_SHA1 instead of ..._MD5
Last modified: 2009-04-01 01:48:15 EDT
Version-Release number of selected component (if applicable):
Disclaimer: I know very little about SCTP, and I don't use it.
The cookies used for connection establishment (similar to TCP SYN cookies) use a configurable hash type. The Fedora kernel currently uses a MD5 HMAC; MD5 is all but broken, it seems prudent to change the configuration to use a SHA-1 HMAC.
I think there has been some concern in the past here that using SHA1 hmacs might be a problem on some older systems that don't support that algorithm. But its probably worth updating rawhide, if for no other reason than to see what breaks.
As far as I understand sctp, these cookies are only used by the host that generated them, so the only possible compatibility problem could arise if the peer has buffers so small that they can not handle the additional 4 bytes.
This has been done:
config-generic:# CONFIG_SCTP_HMAC_NONE is not set
config-generic:# CONFIG_SCTP_HMAC_MD5 is not set