Skip to content

Commit

Permalink
Make sure IV for AES-CBC is initialized
Browse files Browse the repository at this point in the history 
Relates to Azure#14887
  • Loading branch information
@heaths
heaths committed Oct 22, 2020
1 parent 46885d9 commit d56be9d
Show file tree
Hide file tree
Showing 3 changed files with 125 additions and 14 deletions.
3 changes: 3 additions & 0 deletions sdk/keyvault/Azure.Security.KeyVault.Keys/src/Cryptography/AesCryptographyProvider.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -81,6 +81,9 @@ public override EncryptResult Encrypt(EncryptOptions options, CancellationToken
EncryptionAlgorithm algorithm = options.Algorithm;
if (algorithm.GetAesCbcEncryptionAlgorithm() is AesCbc aesCbc)
{
// Make sure the IV is initialized.
options.Initialize();

using ICryptoTransform encryptor = aesCbc.CreateEncryptor(KeyMaterial.K, options.Iv);

byte[] plaintext = options.Plaintext;
Expand Down
8 changes: 8 additions & 0 deletions sdk/keyvault/Azure.Security.KeyVault.Keys/src/Cryptography/RemoteCryptographyClient.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -49,6 +49,10 @@ public virtual async Task<Response<EncryptResult>> EncryptAsync(EncryptOptions o

try
{
// Make sure the IV is initialized.
// TODO: Remove this call once the service will initialized it: https://github.com/Azure/azure-sdk-for-net/issues/16175
options.Initialize();

return await Pipeline.SendRequestAsync(RequestMethod.Post, options, () => new EncryptResult { Algorithm = options.Algorithm }, cancellationToken, "/encrypt").ConfigureAwait(false);
}
catch (Exception e)
Expand All @@ -66,6 +70,10 @@ public virtual Response<EncryptResult> Encrypt(EncryptOptions options, Cancellat

try
{
// Make sure the IV is initialized.
// TODO: Remove this call once the service will initialized it: https://github.com/Azure/azure-sdk-for-net/issues/16175
options.Initialize();

return Pipeline.SendRequest(RequestMethod.Post, options, () => new EncryptResult { Algorithm = options.Algorithm }, cancellationToken, "/encrypt");
}
catch (Exception e)
Expand Down
128 changes: 114 additions & 14 deletions sdk/keyvault/Azure.Security.KeyVault.Keys/tests/AesCryptographyProviderTests.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -137,7 +137,7 @@ public void DecryptionAlgorithmNotSupported()
Assert.AreEqual("invalid", e.GetProperty<string>("algorithm"));
}

[TestCaseSource(nameof(EncryptDecryptRoundtripsData))]
[TestCaseSource(nameof(GetEncryptionAlgorithms), methodParams: new object[] { true })]
public void EncryptDecryptRoundtrips(EncryptionAlgorithm algorithm)
{
// Use a 256-bit key which will be truncated based on the selected algorithm.
Expand Down Expand Up @@ -171,6 +171,73 @@ public void EncryptDecryptRoundtrips(EncryptionAlgorithm algorithm)
#endif
Assert.IsNotNull(encrypted);

switch (algorithm.ToString())
{
// TODO: Move to new test to make sure CryptoClient and LocalCryptoClient initialize a null ICM for AES-CBC(PAD).
case EncryptionAlgorithm.A128CbcValue:
CollectionAssert.AreEqual(
new byte[] { 0x63, 0x23, 0x21, 0xaf, 0x94, 0xf9, 0xe1, 0x21, 0xc2, 0xbd, 0xb1, 0x1b, 0x04, 0x89, 0x8c, 0x3a },
encrypted.Ciphertext);
CollectionAssert.AreEqual(iv, encrypted.Iv);
Assert.IsNull(encrypted.AuthenticationTag);
Assert.IsNull(encrypted.AdditionalAuthenticatedData);
break;

case EncryptionAlgorithm.A192CbcValue:
CollectionAssert.AreEqual(
new byte[] { 0x95, 0x9d, 0x75, 0x91, 0x09, 0x8b, 0x70, 0x0b, 0x9c, 0xfe, 0xaf, 0xcd, 0x60, 0x1f, 0xaa, 0x79 },
encrypted.Ciphertext);
CollectionAssert.AreEqual(iv, encrypted.Iv);
Assert.IsNull(encrypted.AuthenticationTag);
Assert.IsNull(encrypted.AdditionalAuthenticatedData);
break;

case EncryptionAlgorithm.A256CbcValue:
CollectionAssert.AreEqual(
new byte[] { 0xf4, 0xe8, 0x5a, 0xa4, 0xa8, 0xb3, 0xff, 0xc3, 0x85, 0x89, 0x17, 0x9a, 0x70, 0x09, 0x96, 0x7f },
encrypted.Ciphertext);
CollectionAssert.AreEqual(iv, encrypted.Iv);
Assert.IsNull(encrypted.AuthenticationTag);
Assert.IsNull(encrypted.AdditionalAuthenticatedData);
break;

case EncryptionAlgorithm.A128CbcPadValue:
CollectionAssert.AreEqual(
new byte[] { 0xec, 0xb2, 0x63, 0x4c, 0xe0, 0x04, 0xe0, 0x31, 0x2d, 0x9a, 0x77, 0xb2, 0x11, 0xe5, 0x28, 0x7f },
encrypted.Ciphertext);
CollectionAssert.AreEqual(iv, encrypted.Iv);
Assert.IsNull(encrypted.AuthenticationTag);
Assert.IsNull(encrypted.AdditionalAuthenticatedData);
break;

case EncryptionAlgorithm.A192CbcPadValue:
CollectionAssert.AreEqual(
new byte[] { 0xc3, 0x4e, 0x1b, 0xe7, 0x6e, 0xa1, 0xf1, 0xc3, 0x24, 0xae, 0x05, 0x1b, 0x0e, 0x32, 0xac, 0xb4 },
encrypted.Ciphertext);
CollectionAssert.AreEqual(iv, encrypted.Iv);
Assert.IsNull(encrypted.AuthenticationTag);
Assert.IsNull(encrypted.AdditionalAuthenticatedData);
break;

case EncryptionAlgorithm.A256CbcPadValue:
CollectionAssert.AreEqual(
new byte[] { 0x4e, 0xbd, 0x78, 0xda, 0x90, 0x73, 0xc8, 0x97, 0x67, 0x2b, 0xa1, 0x0a, 0x41, 0x67, 0xf8, 0x99 },
encrypted.Ciphertext);
CollectionAssert.AreEqual(iv, encrypted.Iv);
Assert.IsNull(encrypted.AuthenticationTag);
Assert.IsNull(encrypted.AdditionalAuthenticatedData);
break;

case EncryptionAlgorithm.A128GcmValue:
case EncryptionAlgorithm.A192GcmValue:
case EncryptionAlgorithm.A256GcmValue:
Assert.IsNotNull(encrypted.Ciphertext);
Assert.IsNotNull(encrypted.Iv);
Assert.IsNotNull(encrypted.AuthenticationTag);
CollectionAssert.AreEqual(aad, encrypted.AdditionalAuthenticatedData);
break;
}

DecryptOptions decryptOptions = algorithm.IsAesGcm() ?
new DecryptOptions(algorithm, encrypted.Ciphertext, encrypted.Iv, encrypted.AuthenticationTag, encrypted.AdditionalAuthenticatedData) :
new DecryptOptions(algorithm, encrypted.Ciphertext, encrypted.Iv);
Expand All @@ -182,19 +249,52 @@ public void EncryptDecryptRoundtrips(EncryptionAlgorithm algorithm)
StringAssert.StartsWith("plaintext", Encoding.UTF8.GetString(decrypted.Plaintext));
}

private static IEnumerable EncryptDecryptRoundtripsData => new[]
[TestCaseSource(nameof(GetEncryptionAlgorithms), methodParams: new object[] { false })]
public void InitializesIv(EncryptionAlgorithm algorithm)
{
// Use a 256-bit key which will be truncated based on the selected algorithm.
byte[] k = new byte[] { 0xe2, 0x7e, 0xd0, 0xc8, 0x45, 0x12, 0xbb, 0xd5, 0x5b, 0x6a, 0xf4, 0x34, 0xd2, 0x37, 0xc1, 0x1f, 0xeb, 0xa3, 0x11, 0x87, 0x0f, 0x80, 0xf2, 0xc2, 0xe3, 0x36, 0x42, 0x60, 0xf3, 0x1c, 0x82, 0xc8 };

JsonWebKey key = new JsonWebKey(new[] { KeyOperation.Encrypt, KeyOperation.Decrypt })
{
K = k,
};

AesCryptographyProvider provider = new AesCryptographyProvider(key, null);

byte[] plaintext = Encoding.UTF8.GetBytes("plaintext");

EncryptOptions encryptOptions = new EncryptOptions(algorithm, plaintext, null, null);
EncryptResult encrypted = provider.Encrypt(encryptOptions, default);

Assert.IsNotNull(encryptOptions.Iv);
CollectionAssert.AreEqual(encryptOptions.Iv, encrypted.Iv);

DecryptOptions decryptOptions = new DecryptOptions(algorithm, encrypted.Ciphertext, encrypted.Iv);
DecryptResult decrypted = provider.Decrypt(decryptOptions, default);

Assert.IsNotNull(decrypted);

// AES-CBC will be zero-padded.
StringAssert.StartsWith("plaintext", Encoding.UTF8.GetString(decrypted.Plaintext));
}

private static IEnumerable GetEncryptionAlgorithms(bool includeAesGcm)
{
EncryptionAlgorithm.A128Cbc,
EncryptionAlgorithm.A192Cbc,
EncryptionAlgorithm.A256Cbc,

EncryptionAlgorithm.A128CbcPad,
EncryptionAlgorithm.A192CbcPad,
EncryptionAlgorithm.A256CbcPad,

EncryptionAlgorithm.A128Gcm,
EncryptionAlgorithm.A192Gcm,
EncryptionAlgorithm.A256Gcm,
};
yield return EncryptionAlgorithm.A128Cbc;
yield return EncryptionAlgorithm.A192Cbc;
yield return EncryptionAlgorithm.A256Cbc;

yield return EncryptionAlgorithm.A128CbcPad;
yield return EncryptionAlgorithm.A192CbcPad;
yield return EncryptionAlgorithm.A256CbcPad;

if (includeAesGcm)
{
yield return EncryptionAlgorithm.A128Gcm;
yield return EncryptionAlgorithm.A192Gcm;
yield return EncryptionAlgorithm.A256Gcm;
}
}
}
}

0 comments on commit d56be9d

Please sign in to comment.