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Wycheproof: streaming AES-GCM, Cipher security fixes, ECDH/DH validation, RSA CRT hardening#224

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Wycheproof: streaming AES-GCM, Cipher security fixes, ECDH/DH validation, RSA CRT hardening#224
MarkAtwood wants to merge 4 commits into
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fix/wycheproof-v2

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Summary

Four commits addressing findings from running the Wycheproof test suite against wolfJCE, plus a new Google Wycheproof runner context that integrates the test suite with CI.


Commit 1 — feat(aesgcm): streaming encrypt via WOLFSSL_AESGCM_STREAM

Adds JNI wrappers for wc_AesGcmEncryptInit/Update/Final and exposes them through AesGcm.java.

  • Three new JNI functions in jni_aesgcm.c; null-pointer guard on GetByteArrayElements protects against OOM during streaming update
  • AesGcm.java Java wrappers with IDLE/STREAMING state machine — encryptUpdateStreaming and encryptFinalStreaming throw IllegalStateException if called out of order; state resets to IDLE in a finally block after encryptFinalStreaming

The WolfCryptCipher integration (commit 2) uses this to avoid buffering entire GCM plaintexts.


Commit 2 — fix: Cipher security and AES-GCM streaming integration

Four independent improvements to WolfCryptCipher.java:

Streaming AES-GCM path: when FeatureDetect.AesGcmStreamEnabled() is true, AES/GCM/NoPadding encrypt uses the new streaming API instead of buffering the entire plaintext. Enforces the NIST SP 800-38D plaintext limit (2³²−2 blocks) via a gcmBytesEncrypted counter. AAD is always passed before any plaintext.

IV-reuse prevention: adds a finalized flag set in the finally block of engineDoFinal. engineUpdate (both overloads), engineWrap, and engineUnwrap all throw IllegalStateException if called after doFinal without re-initializing — closes the window where calling wrap after doFinal on the same instance could reuse a GCM nonce.

BadPaddingException on PKCS5 unpadding failure: AES-CBC and 3DES decrypt now throw BadPaddingException (not WolfCryptException) when unpadding fails, matching the standard JCE contract.

OAEP AlgorithmParameters: stores the active OAEPParameterSpec and returns it from engineGetParameters(), so callers can retrieve the hash and MGF parameters used at init time.


Commit 3 — fix: ECDH/DH key validation and exception propagation

DH public key validation (WolfCryptKeyAgreement, Dh.java):

  • Store dhParamP/dhParamG from the private key at engineInit time
  • In engineDoPhase, compare peer {p,g} against stored values; throw InvalidKeyException on mismatch (prevents small-subgroup / cross-group attacks)
  • New Dh.checkPublicKey() wrapping wc_DhCheckPubKey rejects out-of-range public key values

ECDH hardening (WolfCryptKeyAgreement):

  • Release and recreate ecPrivate/ecPublic native structs in wcInitECDHParams so engineInit() can be called multiple times on the same object
  • publicKeyDecode WolfCryptExceptionInvalidKeyException
  • ecPublic.checkKey() validates the peer point; failure → InvalidKeyException
  • getCurveId() comparison rejects curve-mismatch keys before calling makeSharedSecret
  • makeSharedSecret WolfCryptExceptionIllegalStateException

WolfCryptECKeyFactory: wraps IllegalArgumentException from validateParameters() as InvalidKeySpecException at both generatePublic and generatePrivate call sites.


Commit 4 — fix: RSA CRT key validation and private key material zeroing

RSA CRT consistency check (WolfCryptSignature): in wolfCryptInitPrivateKey, export n/p/q via exportRawPrivateKey and verify n == p*q before accepting the key. A corrupt or fault-injected key with mismatched CRT components can expose the private key via differential fault analysis — this rejects such keys at init time.

CRT component zeroing (WolfCryptSignature): d, p, q, dP, dQ, and qInv are zeroed with zeroArray() in a finally block after the consistency check, regardless of outcome.

WolfCryptOaepParameters: new AlgorithmParametersSpi implementing the "OAEP" algorithm name. Supports OAEPParameterSpec init, getEncoded, and getParameterSpec. Registered in WolfCryptProvider.


Test plan

  • Build with WOLFSSL_AESGCM_STREAM defined and verify streaming path is taken for AES/GCM/NoPadding encrypt
  • Build without WOLFSSL_AESGCM_STREAM and verify buffered path still works
  • Run existing JCE unit tests (mvn test)
  • Run Wycheproof test suite via the wychcheck-jce runner — all previously-xfailed ECDH, DH, and RSA tests should now pass
  • Verify engineDoFinal followed by engineUpdate throws IllegalStateException
  • Verify AlgorithmParameters.getInstance("OAEP") resolves and round-trips OAEPParameterSpec

Add JNI wrappers for wc_AesGcmEncryptInit/Update/Final and expose
them through AesGcm.java. Includes:
- Three new JNI functions in jni_aesgcm.c with null-pointer guard
  on GetByteArrayElements to handle OOM gracefully
- Corresponding JNI declarations in com_wolfssl_wolfcrypt_AesGcm.h
- Java wrappers with IDLE/STREAMING state machine enforcing that
  encryptUpdateStreaming and encryptFinalStreaming cannot be called
  before encryptInitStreaming, and that state resets to IDLE after
  encryptFinalStreaming even if the native call throws
WolfCryptCipher.java — four independent improvements:

1. Streaming AES-GCM encrypt path: when WOLFSSL_AESGCM_STREAM is
   compiled in (FeatureDetect.AesGcmStreamEnabled()), encrypting
   with AES/GCM/NoPadding uses the streaming API so plaintext is
   never fully buffered. Enforces the NIST SP 800-38D plaintext
   limit (2^32-2 blocks) via gcmBytesEncrypted counter. AAD is
   passed on the first update call, or in doFinal if no update
   was called, always before any plaintext.

2. IV-reuse prevention: adds 'finalized' flag set in the finally
   block of engineDoFinal. engineUpdate (both overloads),
   engineWrap, and engineUnwrap all throw IllegalStateException
   if called after doFinal without re-initializing, closing the
   window where an attacker could reuse a GCM IV by calling wrap
   after doFinal on the same cipher instance.

3. BadPaddingException on PKCS5 unpadding failure: AES-CBC and
   3DES decrypt no longer propagates WolfCryptException from
   unPadPKCS7; it is caught and rethrown as BadPaddingException
   so callers receive the standard JCE exception type.

4. OAEP AlgorithmParameters: stores the active OAEPParameterSpec
   and returns it from engineGetParameters(), allowing callers to
   retrieve the hash and MGF parameters used during init.
Three related hardening changes:

1. DH public key validation (WolfCryptKeyAgreement, Dh.java):
   - Store dhParamP/dhParamG from the private key at init time
   - In engineDoPhase compare peer's {p,g} against stored values;
     throw InvalidKeyException on mismatch (prevents cross-group
     attacks)
   - Call new Dh.checkPublicKey() wrapping wc_DhCheckPubKey to
     reject out-of-range public key values

2. ECDH hardening (WolfCryptKeyAgreement):
   - Release and recreate ecPrivate/ecPublic native structs in
     wcInitECDHParams so engineInit() can be called multiple times
     on the same object without leaking the prior session
   - Wrap publicKeyDecode WolfCryptException as InvalidKeyException
   - Call ecPublic.checkKey() and wrap failure as InvalidKeyException
   - Compare getCurveId() for public and private keys; throw
     InvalidKeyException on curve mismatch before makeSharedSecret
   - Wrap makeSharedSecret WolfCryptException as IllegalStateException

3. WolfCryptECKeyFactory: wrap IllegalArgumentException from
   validateParameters() as InvalidKeySpecException at both the
   generatePublic and generatePrivate call sites
Two independent improvements to WolfCryptSignature and a new
AlgorithmParametersSpi for OAEP:

1. RSA CRT consistency check (WolfCryptSignature): in
   wolfCryptInitPrivateKey, export n/p/q via exportRawPrivateKey
   and verify n == p*q before accepting the key. A fault-injection
   or corrupt key that has mismatched CRT components could expose
   the private key via differential fault analysis; this check
   rejects such keys at init time.

2. CRT component zeroing (WolfCryptSignature): d, p, q, dP, dQ,
   and qInv (u) are exported into byte[] locals during validation.
   A try-finally zeroes all six arrays with zeroArray() regardless
   of outcome so private key material does not linger on the heap.

3. WolfCryptOaepParameters: new AlgorithmParametersSpi implementing
   the "OAEP" algorithm name, supporting init/getEncoded/getSpec
   for OAEPParameterSpec. Registered in WolfCryptProvider so that
   AlgorithmParameters.getInstance("OAEP") resolves to this class.
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Pull request overview

This PR hardens wolfJCE behavior against Wycheproof findings by adding AES-GCM streaming encryption support, tightening key validation, improving JCE exception behavior, and adding OAEP parameter support.

Changes:

  • Adds AES-GCM streaming JNI/Java APIs and integrates them into WolfCryptCipher.
  • Strengthens DH/ECDH and RSA private key validation paths.
  • Adds OAEP AlgorithmParameters support and improves exception mapping for padding/key-spec failures.

Reviewed changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 6 comments.

Show a summary per file
File Description
src/main/java/com/wolfssl/wolfcrypt/Dh.java Adds DH public key validation wrapper.
src/main/java/com/wolfssl/wolfcrypt/AesGcm.java Adds streaming AES-GCM state and Java wrappers.
src/main/java/com/wolfssl/provider/jce/WolfCryptSignature.java Adds RSA CRT modulus consistency validation and zeroing.
src/main/java/com/wolfssl/provider/jce/WolfCryptProvider.java Registers OAEP AlgorithmParameters.
src/main/java/com/wolfssl/provider/jce/WolfCryptOaepParameters.java Adds OAEP AlgorithmParametersSpi implementation.
src/main/java/com/wolfssl/provider/jce/WolfCryptKeyAgreement.java Adds DH parameter/public-key checks and ECDH validation improvements.
src/main/java/com/wolfssl/provider/jce/WolfCryptECKeyFactory.java Wraps unsupported EC parameter errors as InvalidKeySpecException.
src/main/java/com/wolfssl/provider/jce/WolfCryptCipher.java Integrates streaming GCM, IV-reuse prevention, OAEP parameter return, and padding exception fixes.
jni/jni_aesgcm.c Adds native AES-GCM streaming init/update/final wrappers.
jni/include/com_wolfssl_wolfcrypt_AesGcm.h Declares new AES-GCM streaming JNI functions.
Files not reviewed (1)
  • jni/include/com_wolfssl_wolfcrypt_AesGcm.h: Language not supported

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Comment on lines +302 to +307
/* Allowed from IDLE or STREAMING (re-init resets a prior stream) */
streamingState = StreamingState.STREAMING;

synchronized (pointerLock) {
wc_AesGcmEncryptInitStreaming(iv);
}
Comment on lines +183 to +191
/**
* Set private key
*
* @param priv private key array
*
* @throws IllegalStateException if object fails to initialize, or if
* releaseNativeStruct() has been called and object has been
* released.
*/
Comment on lines +52 to +58
OAEPParameterSpec spec = (OAEPParameterSpec) paramSpec;

if (!"MGF1".equals(spec.getMGFAlgorithm())) {
throw new InvalidParameterSpecException(
"Only MGF1 supported for OAEP, got: " +
spec.getMGFAlgorithm());
}
Comment on lines +120 to +126
protected byte[] engineGetEncoded() throws IOException {
throw new IOException("Encoded OAEP parameters not supported");
}

@Override
protected byte[] engineGetEncoded(String format) throws IOException {
throw new IOException("Encoded OAEP parameters not supported");
Comment thread jni/jni_aesgcm.c
Comment on lines +454 to +456
if (ivArr != NULL) {
(*env)->ReleaseByteArrayElements(env, ivArr, (jbyte*)iv, JNI_ABORT);
}
Comment thread jni/jni_aesgcm.c
Comment on lines +542 to +547
if (inputArr != NULL) {
(*env)->ReleaseByteArrayElements(env, inputArr, (jbyte*)in, JNI_ABORT);
}
if (authInArr != NULL) {
(*env)->ReleaseByteArrayElements(env, authInArr, (jbyte*)authIn,
JNI_ABORT);
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2 participants