k/server: Better handling of SCRAM parsing errors

[michael-redpanda]

Before this change, if Redpanda received a badly formatted SCRAM message, it would not respond with an error and the offending client would timeout with no error code. This change will now return an error code and print a more helpful message to the logs.

Fixes: #11349

Backports Required

• none - not a bug fix
• none - this is a backport
• none - issue does not exist in previous branches
• none - papercut/not impactful enough to backport
• v23.1.x
• v22.3.x
• v22.2.x

Release Notes

Improvements

• Redpanda will now gracefully handle badly formatted SCRAM authentication messages

[michael-redpanda]

Example of new error message:

WARN  2023-07-11 21:46:52,044 [shard 0] kafka - server.cc:392 - [127.0.0.1:45364]  Error processing SASL authentication request for rpk: security::scram_exception (scram_algorithm.cc:201 - Invalid SCRAM client first message: n,,n=,r=xaMAKQUpxVDWrxkHYx88H/cuqCU)

[BenPope]

LGTM

[tmgstevens]

Can this include the client_id? Do we have that?

[michael-redpanda]

Can this include the client_id? Do we have that?

It does:

[{IP}:{PORT}] Error processing SASL authentication request for {client.id}

https://github.com/michael-redpanda/redpanda/blob/5ec43ff19c1b5cf7f847e581c224db940611a3b0/src/v/kafka/server/server.cc#L392-L398

[tmgstevens]

It does:

[{IP}:{PORT}] Error processing SASL authentication request for {client.id}

Ah yes - got it!

LGTM, thanks for getting this in.

[vbotbuildovich]

/backport v23.1.x

[vbotbuildovich]

/backport v22.3.x

[vbotbuildovich]

/backport v22.2.x

[vbotbuildovich]

Failed to run cherry-pick command. I executed the commands below:

git checkout -b backport-pr-12042-v22.3.x-660 remotes/upstream/v22.3.x
git cherry-pick -x 5ec43ff19c1b5cf7f847e581c224db940611a3b0

Workflow run logs.

[vbotbuildovich]

Failed to run cherry-pick command. I executed the commands below:

git checkout -b backport-pr-12042-v22.2.x-839 remotes/upstream/v22.2.x
git cherry-pick -x 5ec43ff19c1b5cf7f847e581c224db940611a3b0

Workflow run logs.

[c4milo]

We can verify the fix with https://vectorizedio.grafana.net/d/redpanda-prod-v2/redpanda-clusters-v2?orgId=1&var-datasource=metrics-prod-cloudv2&var-redpanda_id=chhnf2abksi1fj6tastg&var-node=All&var-node_shard=All&var-aggr_criteria=pod,shard&from=now-7d&to=now&editPanel=98

cc: @ncole

[Neustradamus]

Good job!

Linked to:

• State of Play scram-sasl/info#1