Address Fenrir findings

[LinuxJedi]

F-3340: AesGcmStream.final decrypt path passed len(authTag) straight to wc_AesGcmDecryptFinal, letting a caller truncate the verification window (forgery probability ~2^-32 instead of 2^-128 for a 4-byte tag against a 16-byte configuration). Reject len(authTag) != self._tag_bytes and pass self._tag_bytes to wolfSSL, mirroring ChaCha20Poly1305.decrypt. Added test_decrypt_rejects_wrong_tag_length. Also fixed test_encrypt_short_tag which was relying on the bug (decrypt side defaulted to tag_bytes=16 against a 12-byte tag).

F-3089: Declare label as const byte* in the wc_RsaPublicEncrypt_ex and wc_RsaPrivateDecrypt_ex cdefs so CFFI can accept Python bytes without exposing a writable pointer into immutable memory. wolfSSL does not modify label.

F-3090: Declare nonce as const byte* in the wc_InitRngNonce and wc_InitRngNonce_ex cdefs for the same reason.

F-1983, F-1984: Add minimum + upper bounds to requirements/{prod,test, docs}.txt so a hijacked release of cffi, tox, pytest, types-cffi, Sphinx, or sphinx_rtd_theme does not get pulled silently on the next pip install. setup.txt resolves transitively via prod.txt.

[Copilot]

Pull request overview

This PR addresses several Fenrir findings by tightening AES-GCM tag verification semantics, improving CFFI const-correctness for pointer arguments, and adding version bounds to requirements files to reduce supply-chain risk.

Changes:

• Enforce exact authTag length in AesGcmStream.final() decryption and pass the configured tag length to wc_AesGcmDecryptFinal.
• Update/extend AES-GCM stream tests to cover wrong tag length rejection and fix the short-tag decrypt test setup.
• Update CFFI cdefs to use const byte* for RSA OAEP label and RNG nonce parameters; add upper/lower bounds to requirements files.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
wolfcrypt/ciphers.py	Rejects truncated/incorrect tag lengths during AES-GCM stream finalization on decrypt.
tests/test_aesgcmstream.py	Adjusts short-tag decrypt test and adds coverage for rejecting wrong tag lengths.
scripts/build_ffi.py	Marks RSA OAEP label and RNG nonce parameters as const byte* in CFFI cdefs.
requirements/test.txt	Adds bounded versions for tox/pytest/types-cffi.
requirements/prod.txt	Adds bounded version for cffi.
requirements/docs.txt	Adds bounded versions for Sphinx and sphinx_rtd_theme.

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