golang :rsa加密

func Sign(pk, context string) string {
    block, _ := pem.Decode([]byte(pk))
    if block == nil {
        panic("私钥错误")
    }
    private, err := x509.ParsePKCS1PrivateKey(block.Bytes)
    if err != nil {
        panic("PrivateKey error")
    }
    h := crypto.Hash.New(crypto.SHA1)
    h.Write([]byte(context))
    hashed := h.Sum(nil)
    // 进行rsa加密签名
    signedData, err := rsa.SignPKCS1v15(rand.Reader, private, crypto.SHA1, hashed)

    data := base64.StdEncoding.EncodeToString(signedData)
    return data
}