Sign and Verify with Go

func GetSignature(encodedPriKey, rawMsg string) (string, error) {
	rawPriKey, err := base64.StdEncoding.DecodeString(encodedPriKey)
	if err != nil {
		return "", err
	}
	// key
	block, _ := pem.Decode(rawPriKey)
	if block == nil {
		return "", errors.New("ssh: no key found")
	}
	priKey, err := x509.ParsePKCS1PrivateKey(block.Bytes)
	if err != nil {
		return "", err
	}

	// msg
	sha := sha256.New()
	sha.Write([]byte(rawMsg))
	msg := sha.Sum(nil)

	signature, err := rsa.SignPSS(rand.Reader, priKey, crypto.SHA256, msg, nil)
	if err != nil {
		return "", err
	}
	rawSignature := base64.StdEncoding.EncodeToString(signature)
	return rawSignature, nil
}

func VerifySignature(encodedPubKey, rawSignature, rawMsg string) bool {
	rawPubKey, err := base64.StdEncoding.DecodeString(encodedPubKey)
	if err != nil {
		return false
	}

	// key
	block, _ := pem.Decode(rawPubKey)
	if block == nil {
		return false
	}
	pubKey, err := x509.ParsePKCS1PublicKey(block.Bytes)
	if err != nil {
		return false
	}

	// signature
	signature, err := base64.StdEncoding.DecodeString(rawSignature)
	if err != nil {
		return false
	}

	// msg
	sha := sha256.New()
	sha.Write([]byte(rawMsg))
	msg := sha.Sum(nil)

	if err = rsa.VerifyPSS(pubKey, crypto.SHA256, msg, signature, nil); err != nil {
		return false
	}

	return true
}