数据是一个随机的64位整数,像这样分成字节

uint64_t nonce = (some 64 bit integer)
NSData *nonceData = [NSData dataWithBytes: &nonce length: sizeof(nonce)];

根据该数据,我正在创建一个SHA256摘要

int digestLength = CC_SHA256_DIGEST_LENGTH;
uint8_t *digest = malloc(digestLength);
CC_SHA256(nonceData.bytes,(CC_LONG)nonceData.length,digest);
NSData *digestData = [NSData dataWithBytes:digest length:digestLength];

然后使用私钥对其进行签名

size_t signedBufferSize = kMaxCipherBufferSize;
uint8_t *signedBuffer = malloc(kMaxCipherBufferSize);

OSStatus status = SecKeyRawSign(privateKeyRef,kSecPaddingPKCS1SHA256,(const uint8_t *)digestData.bytes,digestData.length,&signedBuffer[0],&signedBufferSize);

NSData *signedData = nil;
if (status == errSecSuccess) {
    signedData = [NSData dataWithBytes:signedBuffer length:signedBufferSize];
}

一切似乎都很好.

然后,在Java服务器中,我正在尝试验证签名数据

PublicKey publicKey = (a public key sent from iOS,X509 encoded)

Long nonce = (64 bit integer sent from iOS)
String signedNonce = (base64 encoded signed data)

ByteBuffer buffer = ByteBuffer.allocate(Long.BYTES);
buffer.putLong(nonce);
byte[] nonceBytes = buffer.array();
byte[] signedNonceBytes = Base64.getDecoder().decode(signedNonce.getBytes());

Signature signer = Signature.getInstance( "SHA256withECDSA" );
signer.initVerify( publicKey );
signer.update( nonceBytes );
Boolean isVerified = signer.verify( signedNonceBytes );

此时,signer.verify()返回false

我也尝试签署普通数据,而不是SHA256摘要,但这也不起作用.

我错过了什么？我正确签署数据吗？我使用正确的填充物吗？是否还有其他事情可以使用SHA256withECDSA算法验证数据？