diff options
| author | Peter Dettman <peter.dettman@bouncycastle.org> | 2024-04-05 14:49:12 +0700 |
|---|---|---|
| committer | Peter Dettman <peter.dettman@bouncycastle.org> | 2024-04-05 14:49:12 +0700 |
| commit | 524db20702dbeeac2dd9b48558e0a18d8c0199df (patch) | |
| tree | 32b34fc6afcea9afd03c826e57b3c3c74e5c9bb7 | |
| parent | TLS: Use more appropriate method to check for ECDH curve (diff) | |
| download | BouncyCastle.NET-ed25519-524db20702dbeeac2dd9b48558e0a18d8c0199df.tar.xz | |
Fix CCM input length check
| -rw-r--r-- | crypto/src/crypto/modes/CcmBlockCipher.cs | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/crypto/src/crypto/modes/CcmBlockCipher.cs b/crypto/src/crypto/modes/CcmBlockCipher.cs index fa583fdef..2f9ec216f 100644 --- a/crypto/src/crypto/modes/CcmBlockCipher.cs +++ b/crypto/src/crypto/modes/CcmBlockCipher.cs @@ -274,7 +274,17 @@ namespace Org.BouncyCastle.Crypto.Modes if (q < 4) { int limitLen = 1 << (8 * q); - if (inLen >= limitLen) + + // no input length adjustment for encryption + int inputAdjustment = 0; + + if (!forEncryption) + { + // input includes 16 additional bytes: CCM flags and n+q values. + inputAdjustment = 1 /* flags */ + 15 /* n + q */; + } + + if (inLen - inputAdjustment >= limitLen) throw new InvalidOperationException("CCM packet too large for choice of q."); } @@ -375,7 +385,17 @@ namespace Org.BouncyCastle.Crypto.Modes if (q < 4) { int limitLen = 1 << (8 * q); - if (inLen >= limitLen) + + // no input length adjustment for encryption + int inputAdjustment = 0; + + if (!forEncryption) + { + // input includes 16 additional bytes: CCM flags and n+q values. + inputAdjustment = 1 /* flags */ + 15 /* n + q */; + } + + if (inLen - inputAdjustment >= limitLen) throw new InvalidOperationException("CCM packet too large for choice of q."); } |