Commit Graph
4 Commits
Author SHA1 Message Date
56f85f76df M9: more signature validation algorithms (SHA-3, RIPEMD-160, Ed25519, P-521, brainpool, PSS, rsa_sha1) (#386)
* M9: more signature validation algorithms

Validation now reads what real signers write, and says when it is weak:

- Digests SHA-224, SHA-512/224, SHA-512/256, SHA3-224/256/384/512 and
  RIPEMD-160, beside SHA-1 and SHA-2.
- RSA PKCS#1 v1.5 for every digest, in `rsa_pad`: the one expected encoding
  is built and compared byte for byte, with or without the DigestInfo's NULL
  (RFC 8017 App. B.1). A signature over the bare digest, which doesn't say
  which hash it uses, is refused. The signature value must be below the
  modulus (RFC 8017 §5.2.2); s and s + n both verified before.
- RSA-PSS with the hash, MGF1 hash and salt length the signature declares.
- ECDSA as DER, non-minimal DER or raw r||s on P-256, P-384, P-521 and
  brainpoolP256r1/P384r1/P512r1 (BSI "plain" ECDSA OIDs too); brainpoolP512r1
  is hand-written on crypto-bigint because no RustCrypto crate has it.
- Ed25519 (RFC 8419), and the legacy adbe.x509.rsa_sha1 format.
- An algorithm PdfCraft can't check is Unknown, never Invalid.
- SHA-1 and RIPEMD-160 signatures validate, but the signature's details say
  the algorithm is weak (wording pinned by tests).
- Encoding irregularities that were tolerated are listed in the details
  (`verify_noting`; `verify` keeps its signature).

Found while testing, each with a regression test that failed before the fix:
a brainpoolP512r1 public key with a coordinate >= p panicked inside
crypto-bigint's `sub_mod` (the certificate comes from the PDF); it is refused
now, and the point at infinity is an invalid signature, not an error.

Vectors were made with OpenSSL (tests/data/README.md has the commands).

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

* Update comment to clarify MAC digest restrictions

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* M9: a legacy x509.rsa_sha1 signature whose key the verifier rejects is Invalid; only unsupported keys are "can't check yet"

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>
2026-10-09 18:44:38 -04:00
Brandon ThomasandClaude Opus 5.5 d3db99818f Rename PrintCraft to PdfCraft (#174)
The app, crates, binaries, bundle id, packaging, icons, screenshots and docs are now
PdfCraft / pdfcraft (repo storytold/pdfcraft). On first launch the desktop app moves the
PrintCraft settings and crash-recovery folders to the new name, and both apps read settings
saved under the old storage key, so upgrades keep recent files, preferences and unsaved work.
The signing test fixtures keep their PrintCraft subject names (they are binary).

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-07 16:03:57 -04:00
Brandon ThomasandClaude Opus 5.5 f58570699e M9: Sign with macOS Keychain identities (keys stay in the Keychain): listed in Sign with a Digital ID; sign_keychain_ids, sign_document id keychain:…
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-02 07:55:07 -04:00
Brandon ThomasandClaude Opus 5.5 e06a98adaa M9.1–M9.3: new sign crate: DER, X.509, CMS SignedData, PKCS #12 (PBES2 and legacy, MAC) on RustCrypto with aws-lc-rs for RSA private keys; PAdES B-B signing (new or existing field, visible or invisible, DocMDP certification) with an incremental placeholder save; validation (digest, signature, chain against a trust store, changes after signing classified under DocMDP); checked against pdfsig and OpenSSL
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-02 02:43:46 -04:00