[test] add tbor crypto command fuzz targets

[David Zimmermann (zimmy87)]

No description provided.

[Copilot]

🟢 Approval recommended

The changes are additive fuzz targets and corresponding Cargo registrations, and the implementations follow existing fuzz-target patterns in this repository.

Pull request overview

Adds new libFuzzer fuzz targets for TBOR crypto-related DDI commands in the fuzz/ crate, expanding emulator-backed round-trip coverage of TBOR request handling for cryptographic operations.

Changes:

• Introduces multiple new TBOR crypto command fuzz targets (AES, ECC, ECDH, HKDF, ConcatKDF, HMAC, RSA mod-exp, unwrap/get-unwrapping-key).
• Bounds fuzzed variable-length inputs to the corresponding TBOR type limits to avoid trivial oversized frames.
• Registers the new fuzz targets as [[bin]] entries in fuzz/Cargo.toml.

File summaries

File	Description
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_unwrap_key.rs	Fuzzes TborUnwrapKeyReq with bounded wrapped blob input.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_rsa_mod_exp.rs	Fuzzes TborRsaModExpReq with bounded masked key and input integer.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_hmac.rs	Fuzzes TborHmacReq, generating a valid masked key via TborHmacGenerateKeyReq.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_hmac_generate_key.rs	Fuzzes TborHmacGenerateKeyReq parameter space.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_hkdf_derive.rs	Fuzzes TborHkdfDeriveReq, deriving a valid masked secret via ECC keygen + ECDH.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_hash.rs	Fuzzes TborHashReq with bounded message input.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_get_unwrapping_key.rs	Fuzzes TborGetUnwrappingKeyReq round-trips.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_ecdh_derive.rs	Fuzzes TborEcdhDeriveReq, generating a valid masked key first.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_ecc_sign.rs	Fuzzes TborEccSignReq, generating a valid masked key first.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_ecc_generate_key.rs	Fuzzes TborEccGenerateKeyReq parameter space.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_concat_kdf_derive.rs	Fuzzes TborConcatKdfDeriveReq, deriving a valid masked secret via ECC keygen + ECDH.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_aes_generate_key.rs	Fuzzes TborAesGenerateKeyReq parameter space.
fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_aes_encrypt_decrypt.rs	Fuzzes TborAesEncryptDecryptReq, generating a valid masked key first.
fuzz/Cargo.toml	Registers the new fuzz target binaries.

Review details

• Files reviewed: 14/14 changed files
• Comments generated: 0
• Review effort level: Lite

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[Copilot]

🔵 Needs a closer look

fuzz_tbor_get_unwrapping_key currently ignores its input, making it ineffective as a fuzz target.

Review details

Suppressed comments (1)

Previously missed (1) — in code that hasn't changed since the last review.

fuzz/fuzz_targets/ddi/tbor/fuzz_tbor_get_unwrapping_key.rs:28

• This fuzz target ignores its input entirely, so the fuzzer can't mutate anything meaningful and coverage will be effectively constant. Consider consuming the input to vary session_id (e.g., sometimes use the real active session id and sometimes a fuzzed one) so validation and error paths are actually fuzzed.

• Files reviewed: 14/14 changed files
• Comments generated: 0 new
• Review effort level: Lite