go-x-crypto/ssh/client_auth_test.go, branch ssh-run-with-context

ssh: add test cases for compatibility with old (buggy) clients

2023-09-20T18:10:32Z

Improved test cases for CL 506835. Change-Id: If4a98ae4a7b39d2e59b203d10080b71283e1a80e Reviewed-on: https://go-review.googlesource.com/c/crypto/+/525735 TryBot-Result: Gopher Robot Reviewed-by: Matthew Dempsky Run-TryBot: Filippo Valsorda Reviewed-by: Ian Lance Taylor Reviewed-by: Filippo Valsorda Auto-Submit: Filippo Valsorda

ssh: add MultiAlgorithmSigner

2023-09-20T18:10:30Z

MultiAlgorithmSigner allows to restrict client-side, server-side and certificate signing algorithms. Fixes golang/go#52132 Fixes golang/go#36261 Change-Id: I295092f1bba647327aaaf294f110e9157d294159 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/508398 Reviewed-by: Filippo Valsorda Run-TryBot: Filippo Valsorda Reviewed-by: Ian Lance Taylor Auto-Submit: Filippo Valsorda TryBot-Result: Gopher Robot Reviewed-by: Matthew Dempsky

ssh: check the declared public key algo against decoded one

2023-09-05T16:18:45Z

This check will ensure we don't accept e.g. ssh-rsa-cert-v01@openssh.com algorithm with ssh-rsa public key type. The algorithm and public key type must be consistent: both must be certificate algorithms, or neither. Change-Id: I1d75074fb4d6db3a8796408e98ddffe577a96ab1 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/506836 TryBot-Result: Gopher Robot Reviewed-by: Dmitri Shuralyov Reviewed-by: Cherry Mui Auto-Submit: Filippo Valsorda Reviewed-by: Filippo Valsorda Run-TryBot: Filippo Valsorda

ssh: fix RSA certificate and public key authentication with older clients

2023-07-10T19:57:54Z

After adding support for rsa-sha2-256/512 on the server side some edge cases started to arise with old clients: 1) public key authentication with gpg-agent < 2.2.6 fails because we receive ssh-rsa as signature format and rsa-sha2-256 or rsa-sha2-512 as algorithm. This is a bug in gpg-agent fixed in this commit: https://github.com/gpg/gnupg/commit/80b775bdbb852aa4a80292c9357e5b1876110c00 2) certificate authentication fails with OpenSSH 7.2-7.7 because we receive ssh-rsa-cert-v01@openssh.com as algorithm and rsa-sha2-256 or rsa-sha2-512 as signature format. This patch is based on CL 412854 and has been tested with every version of OpenSSH from 7.1 to 7.9 and OpenSSH 9.3. Fixes golang/go#53391 Change-Id: Id71f596f73d84efb5c76d6d5388432cccad3e3b1 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/506835 Auto-Submit: Filippo Valsorda Reviewed-by: Filippo Valsorda Run-TryBot: Filippo Valsorda Reviewed-by: Dmitri Shuralyov TryBot-Result: Gopher Robot Reviewed-by: Roland Shoemaker

ssh: support rsa-sha2-256/512 on the server side

2022-11-12T16:25:23Z

This lets clients know we support rsa-sha2-256/512 signatures from ssh-rsa public keys. OpenSSH prefers to break the connection rather than attempting trial and error, apparently. We don't enable support for the "ext-info-s" because we're not interested in any client->server extensions. This also replaces isAcceptableAlgo which was rejecting the rsa-sha2-256/512-cert-v01@openssh.com public key algorithms. Tested with OpenSSH 9.1 on macOS Ventura. Fixes golang/go#49269 Updates golang/go#49952 Co-authored-by: Nicola Murino Co-authored-by: Kristin Davidson Change-Id: I4955c3b12bb45575e9977ac657bb5805b49d00c3 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/447757 Run-TryBot: Filippo Valsorda TryBot-Result: Gopher Robot Reviewed-by: Roland Shoemaker Reviewed-by: Nicola Murino Reviewed-by: Michael Knyszek

ssh: support rsa-sha2-256/512 for client authentication

2022-03-14T23:47:24Z

CL 220037 had implemented support for host authentication using rsa-sha2-256/512, but not client public key authentication. OpenSSH disabled the SHA-1 based ssh-rsa by default in version 8.8 (after pre-announcing it in versions 8.2, 8.3, 8.4, 8.5, 8.6, and 8.7) although some distributions re-enable it. GitHub will start rejecting ssh-rsa for keys uploaded before November 2, 2021 on March 15, 2022. https://github.blog/2021-09-01-improving-git-protocol-security-github/ The server side already worked, as long as the client selected one of the SHA-2 algorithms, because the signature flowed freely to Verify. There was however nothing verifying that the signature algorithm matched the advertised one. The comment suggested the check was being performed, but it got lost back in CL 86190043. Not a security issue because the signature had to pass the callback's Verify method regardless, and both values were checked to be acceptable. Tested with OpenSSH 8.8 configured with "PubkeyAcceptedKeyTypes -ssh-rsa" and no application-side changes. The Signers returned by ssh/agent (when backed by an agent client) didn't actually implement AlgorithmSigner but ParameterizedSigner, an interface defined in an earlier version of CL 123955. Updates golang/go#49269 Fixes golang/go#39885 For golang/go#49952 Change-Id: I13b41db8041f1112a70f106c55f077b904b12cb8 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/392394 Trust: Filippo Valsorda Run-TryBot: Filippo Valsorda TryBot-Result: Gopher Robot Reviewed-by: Roland Shoemaker

ssh: accept WSAECONNABORTED in TestClientAuthMaxAuthTriesPublicKey

2022-02-09T19:56:52Z

Fixes golang/go#50805 Change-Id: Icdd2835b1626240faf61936288f279570c873158 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/381614 Trust: Ian Lance Taylor Run-TryBot: Ian Lance Taylor TryBot-Result: Gopher Robot Reviewed-by: Roland Shoemaker

ssh: add diffie-hellman-group-exchange-sha256

2019-06-17T13:33:40Z

Add the diffie-hellman-group-exchange-sha256 defined in RFC 4419 to the list of supported key exchange algorithms for ssh. The server half is only a minimal implementation to satisfy the automated tests. Fixes golang/go#17230 Change-Id: I25880a564347fd9b4738dd2ed1e347cd5d2e21bb GitHub-Last-Rev: 9f0b8d02c0c96e9baf00cdf1cf063ff834245443 GitHub-Pull-Request: golang/crypto#87 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/174257 Run-TryBot: Han-Wen Nienhuys TryBot-Result: Gobot Gobot Reviewed-by: Han-Wen Nienhuys

ssh/gss: support kerberos authentication for ssh server and client

2019-05-10T10:41:15Z

Change-Id: I20e3356476dc50402dd34d2b39ad030c1e63a9ef Reviewed-on: https://go-review.googlesource.com/c/crypto/+/170919 Run-TryBot: Han-Wen Nienhuys TryBot-Result: Gobot Gobot Reviewed-by: Han-Wen Nienhuys

ssh: remove testing.T from ExampleRetryableAuthMethod

2019-04-11T14:11:41Z

Change-Id: I9cb821827b16d60b0a8c4fff9caec78748f3a495 Reviewed-on: https://go-review.googlesource.com/c/crypto/+/171677 Reviewed-by: Brad Fitzpatrick