The RFC is clear that the Parameters in an AlgorithmIdentifer for an RSA
public key must be NULL. BoringSSL enforces this so we have strong
evidence that this is a widely compatible change.
Embarrassingly enough, the major source of violations of this is us. Go
used to get this correct in only one of two places. This was only fixed
in 2013 (with 4874bc9b). That's why lots of test certificates are
updated in this change.
Fixes#16166.
Change-Id: Ib9a4551349354c66e730d44eb8cee4ec402ea8ab
Reviewed-on: https://go-review.googlesource.com/27312
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
A new attack on CBC padding in SSLv3 was released yesterday[1]. Go only
supports SSLv3 as a server, not as a client. An easy fix is to change
the default minimum version to TLS 1.0 but that seems a little much
this late in the 1.4 process as it may break some things.
Thus this patch adds server support for TLS_FALLBACK_SCSV[2] -- a
mechanism for solving the fallback problem overall. Chrome has
implemented this since February and Google has urged others to do so in
light of yesterday's news.
With this change, clients can indicate that they are doing a fallback
connection and Go servers will be able to correctly reject them.
[1] http://googleonlinesecurity.blogspot.com/2014/10/this-poodle-bites-exploiting-ssl-30.html
[2] https://tools.ietf.org/html/draft-ietf-tls-downgrade-scsv-00
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/157090043