DLPVerifyDSA¶
Verifies the input DSA digital signature.
Syntax¶
IppStatus ippsDLPVerifyDSA(const IppsBigNumState* pMsg, const IppsBigNumState* pSignR, const IppsBigNumState* pSignS, IppDLResult* pResult, IppsDLPState* pCtx);
Include Files¶
ippcp.h
Parameters¶
pMsg |
Pointer to the message representation msgRep. |
pSignR |
Pointer to the signature r-component to be verified. |
pSignS |
Pointer to the signature s-component to be verified. |
pResult |
Pointer to the result of the verification. |
pCtx |
Pointer to the cryptosystem context. |
Description¶
The function verifies the input DSA digital signature’s components *pSignR and *pSignS with the supplied message representation msgRep. Signer’s public key must be stored by the DLPSetKeyPair function before the DLPVerifyDSA operation.
The function sets the *pResult to ippDLValid if it validates the input DSA digital signature, or to ippDLInvalidSignature if the DSA digital signature verification fails.
Example “Use of DLPSignDSA and DLPVerifyDSA” illustrates the use of functions DLPSignDSA and DLPVerifyDSA. The example uses the BigNumber class and functions creating some cryptographic contexts, whose source code can be found in Appendix B.
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 the context parameter does not match the operation. |
ippStsIncompleteContextErr |
Indicates an error condition if the cryptosystem context has not been properly set up. |
ippStsMessageErr |
Indicates an error condition if the value of msgRep is negative or greater than the multiplicative subgroup characteristic (q). Note, that since IPP 2021.4 the msgRep parameter can be any non-negative value. |