diff options
Diffstat (limited to 'libjava/classpath/gnu/javax/crypto/key/dh/DiffieHellmanKeyAgreement.java')
| -rw-r--r-- | libjava/classpath/gnu/javax/crypto/key/dh/DiffieHellmanKeyAgreement.java | 91 |
1 files changed, 38 insertions, 53 deletions
diff --git a/libjava/classpath/gnu/javax/crypto/key/dh/DiffieHellmanKeyAgreement.java b/libjava/classpath/gnu/javax/crypto/key/dh/DiffieHellmanKeyAgreement.java index 5b1caa7d1b5..2443950549a 100644 --- a/libjava/classpath/gnu/javax/crypto/key/dh/DiffieHellmanKeyAgreement.java +++ b/libjava/classpath/gnu/javax/crypto/key/dh/DiffieHellmanKeyAgreement.java @@ -49,78 +49,63 @@ import java.math.BigInteger; import javax.crypto.interfaces.DHPrivateKey; /** - * <p>The basic version of the Diffie-Hellman key agreement is described in the - * Handbook of Applied Cryptography [HAC] as follows:</p> + * The basic version of the Diffie-Hellman key agreement is described in the + * Handbook of Applied Cryptography [HAC] as follows: * <ul> - * <li>An appropriate prime p and generator g of Z<sub>p</sub><sup>*</sup> - * (2 <= g <= p-2) are selected and published.</li> - * <li>A and B each send the other one message over an open channel; as a - * result, they both can then compute a shared secret key K which they can - * use to protect their future communication.</li> - * <li>A chooses a random secret x, 1 <= x <= p-2, and sends B message - * (1) which is g^x mod p.</li> - * <li>B chooses a random secret y, 1 <= y <= p-2, and sends A message - * (2) which is g^y mod p.</li> - * <li>B receives message (1) and computes the shared key as K = (g^x)^y mod - * p.</li> - * <li>A receives message (2) and computes the shared key as K = (g^y)^x mod - * p.</li> + * <li>An appropriate prime p and generator g of Z<sub>p</sub><sup>*</sup> + * (2 <= g <= p-2) are selected and published.</li> + * <li>A and B each send the other one message over an open channel; as a + * result, they both can then compute a shared secret key K which they can use + * to protect their future communication.</li> + * <li>A chooses a random secret x, 1 <= x <= p-2, and sends B message + * (1) which is g^x mod p.</li> + * <li>B chooses a random secret y, 1 <= y <= p-2, and sends A message + * (2) which is g^y mod p.</li> + * <li>B receives message (1) and computes the shared key as K = (g^x)^y mod p. + * </li> + * <li>A receives message (2) and computes the shared key as K = (g^y)^x mod p. + * </li> * </ul> - * - * <p>RFC-2631 describes a <i>Static-Static Mode</i> of operations with - * Diffie-Hellman keypairs as follows:</p> + * <p> + * RFC-2631 describes a <i>Static-Static Mode</i> of operations with + * Diffie-Hellman keypairs as follows: * <pre> - * "In Static-Static mode, both the sender and the recipient have a - static (and certified) key pair. Since the sender's and recipient's - keys are therefore the same for each message, ZZ will be the same for - each message. Thus, partyAInfo MUST be used (and different for each - message) in order to ensure that different messages use different - KEKs. Implementations MAY implement Static-Static mode." + * "In Static-Static mode, both the sender and the recipient have a + * static (and certified) key pair. Since the sender's and recipient's + * keys are therefore the same for each message, ZZ will be the same for + * each message. Thus, partyAInfo MUST be used (and different for each + * message) in order to ensure that different messages use different + * KEKs. Implementations MAY implement Static-Static mode." * </pre> - * - * <p>Reference:</p> + * + * <p> + * Reference: * <ol> - * <li><a href="http://www.ietf.org/rfc/rfc2631.txt">Diffie-Hellman Key - * Agreement Method</a><br> - * Eric Rescorla.</li> - * <li><a href="http://www.cacr.math.uwaterloo.ca/hac">[HAC]</a>: Handbook of - * Applied Cryptography.<br> - * CRC Press, Inc. ISBN 0-8493-8523-7, 1997<br> - * Menezes, A., van Oorschot, P. and S. Vanstone.</li> + * <li><a href="http://www.ietf.org/rfc/rfc2631.txt">Diffie-Hellman Key + * Agreement Method</a><br> + * Eric Rescorla.</li> + * <li><a href="http://www.cacr.math.uwaterloo.ca/hac">[HAC]</a>: Handbook of + * Applied Cryptography.<br> + * CRC Press, Inc. ISBN 0-8493-8523-7, 1997<br> + * Menezes, A., van Oorschot, P. and S. Vanstone.</li> * </ol> */ -public abstract class DiffieHellmanKeyAgreement extends BaseKeyAgreementParty +public abstract class DiffieHellmanKeyAgreement + extends BaseKeyAgreementParty { - - // Constants and variables - // ------------------------------------------------------------------------- - public static final String SOURCE_OF_RANDOMNESS = "gnu.crypto.dh.ka.prng"; - - public static final String KA_DIFFIE_HELLMAN_OWNER_PRIVATE_KEY = "gnu.crypto.dh.ka.owner.private.key"; - + public static final String KA_DIFFIE_HELLMAN_OWNER_PRIVATE_KEY = + "gnu.crypto.dh.ka.owner.private.key"; /** The key agreement party's private key. */ protected DHPrivateKey ownerKey; - /** The shared secret key. */ protected BigInteger ZZ; - // Constructor(s) - // ------------------------------------------------------------------------- - protected DiffieHellmanKeyAgreement() { super(Registry.DH_KA); } - // Class methods - // ------------------------------------------------------------------------- - - // Instance methods - // ------------------------------------------------------------------------- - - // implementation of common abstract methods in BaseKeyAGreementParty ------ - protected byte[] engineSharedSecret() throws KeyAgreementException { return Util.trim(ZZ); |
