Developer Reference

Contents

GFpECSignNR

Computes the digital signature over a message digest (the Nyberg-Rueppel scheme).

Syntax

IppStatus ippsGFpECSignNR(const IppsBigNumState*
pMsgDigest
, const IppsBigNumState*
pRegPrivate
, const IppsBigNumState*
pEphPrivate
, IppsBigNumState*
pSignR
, IppsBigNumState*
pSignS
, IppsGFpECState*
pEC
, Ipp8u*
pScratchBuffer
);
Include Files
ippcp.h
Parameters
pMsgDigest
Pointer to the message digest
msg
to be digitally signed, that is, to be ecrypted with a private key.
pRegPrivate
Pointer to the regular private key of the signer.
pEphPrivate
Pointer to the ephemeral private key of the signer.
pSignR
Pointer to the integer
r
of the digital signature.
pSignS
Pointer to the integer
s
of the digital signature.
pEC
Pointer to the context of the elliptic curve.
pScratchBuffer
Pointer to the scratch buffer.
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 regular private key
regPrivKey
and the ephemeral private key
ephPrivKey
can be generated by the functions GFpECPrivateKey and GFpECPublicKey with only the requirement that the key
regPrivKey
be different from the key
ephPrivKey
.
The elliptic curve domain parameters must be hitherto defined by the functions: GFpECInitStd, GFpECInit, GFpECSet, or GFpECSetSubgroup.
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 any of the contexts pointed by
pMsgDigest
,
pRegPrivate
,
pEphPrivate
,
pSignR
,
pSignS
, or
pEC
does not match the operation.
ippStsMessageErr
Indicates an error condition if the value of
msg
pointed to 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 any of the parameters pointed to by
pSignR
or
pSignS
has a memory size that is less than the order
n
of the elliptic curve base point
G
.
ippStsIvalidPrivateKey
Indicates an error condition if any of the parameters pointed to by
pRegPrivate
or
pEphPrivate
has a memory size that is less than the order
n
of the elliptic curve base point
G
.
ippStsNotSupportedModeErr
Indicates an error condition if the finite field GFp under the elliptic curve is not prime.
ippStsErr
Indicates an error condition if the ephemeral private key is bad.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.