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Version: 3.0.0-beta

HMAC Generate Signature Examples

Python 3#

import base64
import hashlib
import hmac

secret = bytes('the shared secret key here', 'utf-8')
message = bytes('this is signature string', 'utf-8')


hash = hmac.new(secret, message, hashlib.sha256)

# to lowercase hexits
hash.hexdigest()

# to lowercase base64
base64.b64encode(hash.digest())

Java#

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import javax.xml.bind.DatatypeConverter;

class Main {
public static void main(String[] args) {
try {
String secret = "the shared secret key here";
String message = "this is signature string";

Mac hasher = Mac.getInstance("HmacSHA256");
hasher.init(new SecretKeySpec(secret.getBytes(), "HmacSHA256"));

byte[] hash = hasher.doFinal(message.getBytes());

// to lowercase hexits
DatatypeConverter.printHexBinary(hash);

// to base64
DatatypeConverter.printBase64Binary(hash);
}
catch (NoSuchAlgorithmException e) {}
catch (InvalidKeyException e) {}
}
}

Go#

package main

import (
"crypto/hmac"
"crypto/sha256"
"encoding/base64"
"encoding/hex"
)

func main() {
secret := []byte("the shared secret key here")
message := []byte("this is signature string")

hash := hmac.New(sha256.New, secret)
hash.Write(message)

// to lowercase hexits
hex.EncodeToString(hash.Sum(nil))

// to base64
base64.StdEncoding.EncodeToString(hash.Sum(nil))
}

Ruby#

require 'base64'
require 'openssl'

secret = 'the shared secret key here'
message = 'this is signature string'

# to lowercase hexits
OpenSSL::HMAC.hexdigest('sha256', secret, message)

# to base64
Base64.encode64(OpenSSL::HMAC.digest('sha256', secret, message))

NodeJs#

var crypto = require('crypto');

var secret = 'the shared secret key here';
var message = 'this is signature string';

var hash = crypto.createHmac('sha256', secret).update(message);

// to lowercase hexits
hash.digest('hex');

// to base64
hash.digest('base64');

JavaScript ES6#

const secret = 'the shared secret key here';
const message = 'this is signature string';

const getUtf8Bytes = str =>
new Uint8Array(
[...unescape(encodeURIComponent(str))].map(c => c.charCodeAt(0))
);

const secretBytes = getUtf8Bytes(secret);
const messageBytes = getUtf8Bytes(message);

const cryptoKey = await crypto.subtle.importKey(
'raw', secretBytes, { name: 'HMAC', hash: 'SHA-256' },
true, ['sign']
);
const sig = await crypto.subtle.sign('HMAC', cryptoKey, messageBytes);

// to lowercase hexits
[...new Uint8Array(sig)].map(b => b.toString(16).padStart(2, '0')).join('');

// to base64
btoa(String.fromCharCode(...new Uint8Array(sig)));

PHP#

<?php

$secret = 'the shared secret key here';
$message = 'this is signature string';

// to lowercase hexits
hash_hmac('sha256', $message, $secret);

// to base64
base64_encode(hash_hmac('sha256', $message, $secret, true));

Lua#

local hmac = require("resty.hmac")
local secret = 'the shared secret key here'
local message = 'this is signature string'
local digest = hmac:new(secret, hmac.ALGOS.SHA256):final(message)

--to lowercase hexits
ngx.say(digest)

--to base64
ngx.say(ngx.encode_base64(digest))

Shell#

SECRET="the shared secret key here"
MESSAGE="this is signature string"

# to lowercase hexits
echo -e $MESSAGE | openssl dgst -sha256 -hmac $SECRET

# to base64
echo -e $MESSAGE | openssl dgst -sha256 -hmac $SECRET -binary | base64