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| author | Peter Dettman <peter.dettman@bouncycastle.org> | 2017-06-10 18:30:41 +0700 |
|---|---|---|
| committer | Peter Dettman <peter.dettman@bouncycastle.org> | 2017-06-10 18:30:41 +0700 |
| commit | 4362f11288b1c5abd7c9c31b094e19e9f035ede5 (patch) | |
| tree | d2bf0a73c17afea08a4a670e6b1e6be84b73d409 /crypto/src | |
| parent | Added s box allocation to AesEngine (diff) | |
| download | BouncyCastle.NET-ed25519-4362f11288b1c5abd7c9c31b094e19e9f035ede5.tar.xz | |
Checks on DH peer public key
Diffstat (limited to 'crypto/src')
| -rw-r--r-- | crypto/src/crypto/agreement/DHAgreement.cs | 6 | ||||
| -rw-r--r-- | crypto/src/crypto/agreement/DHBasicAgreement.cs | 8 | ||||
| -rw-r--r-- | crypto/src/crypto/parameters/DHPublicKeyParameters.cs | 2 |
3 files changed, 13 insertions, 3 deletions
diff --git a/crypto/src/crypto/agreement/DHAgreement.cs b/crypto/src/crypto/agreement/DHAgreement.cs index b5af104f9..e988c0d53 100644 --- a/crypto/src/crypto/agreement/DHAgreement.cs +++ b/crypto/src/crypto/agreement/DHAgreement.cs @@ -85,7 +85,11 @@ namespace Org.BouncyCastle.Crypto.Agreement BigInteger p = dhParams.P; - BigInteger result = pub.Y.ModPow(privateValue, p); + BigInteger peerY = pub.Y; + if (peerY == null || peerY.CompareTo(BigInteger.One) <= 0 || peerY.CompareTo(p.Subtract(BigInteger.One)) >= 0) + throw new ArgumentException("Diffie-Hellman public key is weak"); + + BigInteger result = peerY.ModPow(privateValue, p); if (result.Equals(BigInteger.One)) throw new InvalidOperationException("Shared key can't be 1"); diff --git a/crypto/src/crypto/agreement/DHBasicAgreement.cs b/crypto/src/crypto/agreement/DHBasicAgreement.cs index d6f017e32..6c3fe6595 100644 --- a/crypto/src/crypto/agreement/DHBasicAgreement.cs +++ b/crypto/src/crypto/agreement/DHBasicAgreement.cs @@ -56,7 +56,13 @@ namespace Org.BouncyCastle.Crypto.Agreement if (!pub.Parameters.Equals(dhParams)) throw new ArgumentException("Diffie-Hellman public key has wrong parameters."); - BigInteger result = pub.Y.ModPow(key.X, dhParams.P); + BigInteger p = dhParams.P; + + BigInteger peerY = pub.Y; + if (peerY == null || peerY.CompareTo(BigInteger.One) <= 0 || peerY.CompareTo(p.Subtract(BigInteger.One)) >= 0) + throw new ArgumentException("Diffie-Hellman public key is weak"); + + BigInteger result = peerY.ModPow(key.X, p); if (result.Equals(BigInteger.One)) throw new InvalidOperationException("Shared key can't be 1"); diff --git a/crypto/src/crypto/parameters/DHPublicKeyParameters.cs b/crypto/src/crypto/parameters/DHPublicKeyParameters.cs index 1704c47dc..e7aeeff19 100644 --- a/crypto/src/crypto/parameters/DHPublicKeyParameters.cs +++ b/crypto/src/crypto/parameters/DHPublicKeyParameters.cs @@ -46,7 +46,7 @@ namespace Org.BouncyCastle.Crypto.Parameters this.y = Validate(y, parameters); } - public BigInteger Y + public virtual BigInteger Y { get { return y; } } |