diff options
| -rw-r--r-- | crypto/src/crypto/engines/RSACoreEngine.cs | 5 | ||||
| -rw-r--r-- | crypto/src/crypto/tls/TlsRsaKeyExchange.cs | 12 |
2 files changed, 12 insertions, 5 deletions
diff --git a/crypto/src/crypto/engines/RSACoreEngine.cs b/crypto/src/crypto/engines/RSACoreEngine.cs index dcc8d0101..a20b22b38 100644 --- a/crypto/src/crypto/engines/RSACoreEngine.cs +++ b/crypto/src/crypto/engines/RSACoreEngine.cs @@ -82,7 +82,10 @@ namespace Org.BouncyCastle.Crypto.Engines BigInteger input = new BigInteger(1, inBuf, inOff, inLen); - if (input.CompareTo(m_key.Modulus) >= 0) + if (input.CompareTo(BigInteger.One) <= 0) + throw new DataLengthException("input too small for RSA cipher."); + + if (input.CompareTo(m_key.Modulus.Subtract(BigInteger.One)) >= 0) throw new DataLengthException("input too large for RSA cipher."); return input; diff --git a/crypto/src/crypto/tls/TlsRsaKeyExchange.cs b/crypto/src/crypto/tls/TlsRsaKeyExchange.cs index 20c2360ea..7e38a529f 100644 --- a/crypto/src/crypto/tls/TlsRsaKeyExchange.cs +++ b/crypto/src/crypto/tls/TlsRsaKeyExchange.cs @@ -125,11 +125,15 @@ namespace Org.BouncyCastle.Crypto.Tls private static BigInteger ConvertInput(BigInteger modulus, byte[] buf, int off, int len) { - BigInteger result = BigIntegers.FromUnsignedByteArray(buf, off, len); - if (result.CompareTo(modulus) < 0) - return result; + BigInteger input = BigIntegers.FromUnsignedByteArray(buf, off, len); - throw new DataLengthException("input too large for RSA cipher."); + if (input.CompareTo(BigInteger.One) <= 0) + throw new DataLengthException("input too small for RSA cipher."); + + if (input.CompareTo(modulus.Subtract(BigInteger.One)) >= 0) + throw new DataLengthException("input too large for RSA cipher."); + + return input; } private static BigInteger Rsa(RsaKeyParameters privateKey, BigInteger input) |