ECCPSignNR¶
Computes the digital signature over a message digest (the Nyberg-Rueppel scheme).
Syntax¶
IppStatus ippsECCPSignNR(const IppsBigNumState* pMsgDigest, const IppsBigNumState* pPrivate, IppsBigNumState* pSignX, IppsBigNumState* pSignY, IppsECCPState* pECC);
Include Files¶
ippcp.h
Parameters¶
pMsgDigest |
Pointer to the message digest msg. |
pPrivate |
Pointer to the private key |
pSignX |
Pointer to the integer r of the digital signature. |
pSignY |
Pointer to the integer s of the digital signature. |
pECC |
Pointer to the context of the elliptic cryptosystem. |
Description¶
The function computes two large numbers r and s which form the digital signature over a message digest msg.
The scheme used to compute the digital signature is an elliptic curve analogue of the El-Gamal Digital Signature scheme with the message recovery (the Nyberg-Rueppel signature scheme). The scheme that the given function uses assumes that the following cryptosystem keys are hitherto set up by the message sender:
regPrivKey |
Regular private key. |
ephPrivKey |
Ephemeral private key. |
ephPubKey |
Ephemeral public key. |
For security reasons, each signature must be generated with the unique ephemeral private key. Because of this, the function clears (sets to zero) the input ephemeral key before return. To generate and set up the keys before sign generation, call the ECCPGenKeyPair and ECCPSetKeyPair functions.
The elliptic curve domain parameters must be hitherto defined by one of the functions: ECCPSet or ECCPSetStd.
For more information on digital signatures, please refer to the [ANSI] standard.
Return Values¶
ippStsNoErr |
Indicates no error. Any other value indicates an error or warning. |
ippStsNullPtrErr |
Indicates an error condition if any of the specified pointers is NULL. |
ippStsContextMatchErr |
Indicates an error condition if one of the contexts pointed by pMsgDigest, pSignX, pSignY, or ECC is not valid. |
ippStsMessageErr |
Indicates an error condition if the value of msg pointed by pMsgDigest falls outside the range of [1, n-1] where n is the order of the elliptic curve base point G. |
ippStsRangeErr |
Indicates an error condition if one of the parameters pointed by pSignX or pSignY has memory size smaller than the order n of the elliptic curve base point G. |
ippStsEphemeralKeyErr |
Indicates an error condition if the values of the ephemeral keys ephPrivKey and ephPubKey are not valid (r = 0 is received as a result of the digital signature calculation). |
ippStsInvalidPrivateKey |
Indicates an error condition if the value of the private key does not belong to the [0, |