tree faf0ede16173b4db863bdef8fccbe7b6b93fad55
parent 270bf2552c05c1943a1c950e3afa3a15663e0277
author Nicola Murino <nicola.murino@gmail.com> 1689510308 +0200
committer Gopher Robot <gobot@golang.org> 1700760194 +0000

ssh: fix certificate authentication with OpenSSH 7.2-7.7

OpenSSH 7.2-7.7 advertises support for rsa-sha2-256 and rsa-sha2-512
in the "server-sig-algs" extension but doesn't support these
algorithms for certificate authentication, so if the server rejects
the key try to use the obtained algorithm as if "server-sig-algs" had
not been implemented.

Fixes golang/go#58371

Change-Id: Id49960d3dedd32a21e2c6c2689b1696e05398286
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/510155
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Run-TryBot: Nicola Murino <nicola.murino@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Nicola Murino <nicola.murino@gmail.com>