fix(identity): create key/cert files with target mode from the start - #156
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jamofer
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What
Create the identity key/cert files with their final mode instead of
fopen+chmod-after-write.Why
Audit SEC-3 (private-key TOCTOU).
writePemWithModedidfopen(path, "w")— creating the file at0666 & ~umask(typically 0644) — wrote the PKCS#8 private key bytes, thenchmod 0600. Between write and chmod the private key was group/world-readable on disk.How
open(path, O_WRONLY|O_CREAT|O_TRUNC, mode)+fchmod(fd, mode)before any bytes, viafdopen. The key is never observable at a wider mode; also forces exact perms regardless of umask.Testing
make testgreen (384/384),make releasecleanagent.keyis600,agent.crt644from creationNotes
Linux identity only. Windows identity (ACL-based) and
pin_store(writes public fingerprints, not secrets) are out of scope here; track separately if wanted.