func doesPolicySignatureV2Match(formValues http.Header) (auth.Credentials, APIErrorCode) {
	accessKey := formValues.Get(xhttp.AmzAccessKeyID)

	r := &http.Request{Header: formValues}
	cred, _, s3Err := checkKeyValid(r, accessKey)
	if s3Err != ErrNone {
		return cred, s3Err
	}
	policy := formValues.Get("Policy")
	signature := formValues.Get(xhttp.AmzSignatureV2)

			return auth.Credentials{}, false, ErrMissingFields
		}
		ch, s3Err = parseCredentialHeader(authFields[0], region, stype)
		if s3Err != ErrNone {
			return auth.Credentials{}, false, s3Err
		}
	}
	return checkKeyValid(r, ch.accessKey)
}

// parse credentialHeader string into its structured form.
func parseCredentialHeader(credElement string, region string, stype serviceType) (ch credentialHeader, aec APIErrorCode) {

	extractedSignedHeaders, errCode := extractSignedHeaders(signV4Values.SignedHeaders, r)
	if errCode != ErrNone {
		return cred, "", "", time.Time{}, errCode
	}

	cred, _, errCode = checkKeyValid(r, signV4Values.Credential.accessKey)
	if errCode != ErrNone {
		return cred, "", "", time.Time{}, errCode
	}

	// Verify if region is valid.
	region = signV4Values.Credential.scope.region