https://gitlab.synchro.net/main/sbbs/-/commit/4781761a1bdbbe54562ed0b4
Modified Files:
src/syncterm/ssh.c
Log Message:
SyncTERM: warn the user about weak SSH host keys
Treat any RSA-family host key under 2048 bits as weak (NIST 2024 floor;
Ed25519 is always 256 and considered strong). The host-key verify
callback now stashes the algorithm name and key size so the post-
handshake UI can act on it:
- HOSTKEY_NEW + weak: prompt "Weak host key (NNNN-bit algo)" with a
Disconnect/Accept choice instead of silent TOFU. Under hidepopups
(no human present) refuse the connection rather than auto-trust a
weak key.
- HOSTKEY_MISMATCH + weak: existing change-fingerprint dialog grows a
"WARNING: the new key is a NNNN-bit algo, below the 2048-bit safety
floor" block, and the title itself becomes "Fingerprint Changed —
WEAK NNNN-bit algo key" so the warning is visible without F1.
- Strong keys: behaviour unchanged (NEW silently TOFU's, MISMATCH
uses the original dialog).
Co-Authored-By: Claude Opus 4.7 (1M context) <
noreply@anthropic.com>
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