CRYPT_ECC_DSA_HashVerify Function

C

int CRYPT_ECC_DSA_HashVerify(
    CRYPT_ECC_CTX* ecc, 
    const unsigned char* sig, 
    unsigned int sigSz, 
    unsigned char* hash, 
    unsigned int hashSz, 
    int* status
);

Description

This function verifies that an ECC signature is valid.

Preconditions

The ECC context must have been initialized with a call to CRYPT_ECC_Initialize. The key used for the signature must have been imported or created prior to calling this function.

Parameters

Parameters	Description
ecc	Pointer to context which saves state between calls.
sig	The signature to verify.
sigSz	The length of the signature (octets).
hash	The hash (message digest) that was signed.
hashSz	The length of the hash (octets).
status	Result of signature (1 == valid, 0 == invalid).

Returns

BAD_FUNC_ARG - An invalid pointer was passed to the function.
MEMORY_E - Memory could not be allocated for the operation.
0 - An invalid pointer was not passed to the function.

Remarks

None.

Example

CRYPT_ECC_CTX userA; 
int           ret;
byte          sig[100];
unsigned int  sigSz = (unsigned int)sizeof(sig);
unsigned int  usedA = 0;
int verifyStatus = 0;

ret = CRYPT_ECC_Initialize(&userA);
...
// Import or generate private key
...
ret = CRYPT_ECC_DSA_HashVerify(&userA, sig, sigSz, ourData, CRYPT_SHA_DIGEST_SIZE, &verifyStatus);