tskagent: fix incorrect comment parsing from key files#1
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The code to pull comments out of key data made some heuristic (but incorrect) assumptions about the organization of the key. In particular, for keys where no comment is defined, it could incorrectly grab an earlier field (e.g., one of the key parameters) which would confuse a client expecting printable text. Correctly process the fields we care about, so that when an empty comment is set we don't grab the wrong thing by mistake. Also, update the tests to cover RSA as well as ED25519 keys, and generate test keys randomly. I ran the new tests 50,000 times under "stress" and was not able to produce any new failures. Thanks to @andrew-d for reporting this and for providing a failing test to debug from. Co-authored-by: Andrew Dunham <andrew@tailscale.com>
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| }, | ||
| { | ||
| name: "RSA/Comment", | ||
| input: mustGenerateKey(t, genRSA, "what year is it"), |
creachadair
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As noted in #1, we rely on the keys not being passphrase locked, since the agent has no way to prompt a user for the passphrase. Also add an example.
creachadair
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As noted in #1, we rely on the keys not being passphrase locked, since the agent has no way to prompt a user for the passphrase. Also add an example.
creachadair
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Jun 6, 2026
As noted in #1, we rely on the keys not being passphrase locked, since the agent has no way to prompt a user for the passphrase. Also add an example.
creachadair
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Jun 6, 2026
As noted in #1, we rely on the keys not being passphrase locked, since the agent has no way to prompt a user for the passphrase. Also add an example.
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The code to pull comments out of key data made some heuristic (but incorrect)
assumptions about the organization of the key. In particular, for keys where no
comment is defined, it could incorrectly grab an earlier field (e.g., one of
the key parameters) which would confuse a client expecting printable text.
Correctly process the fields we care about, so that when an empty comment is
set we don't grab the wrong thing by mistake.
Also, update the tests to cover RSA as well as ED25519 keys, and generate test
keys randomly. I ran the new tests 50,000 times under "stress" and was not able
to produce any new failures.
Thanks to @andrew-d for reporting this and for providing a failing test to
debug from.
Co-authored-by: Andrew Dunham andrew@tailscale.com