Crypto Module

The Functions' crypto module provides hashing, HMAC, signing, and verification helpers for PubNub Functions. Use it to protect data and validate messages in real time.

Import the module:

1const crypto = require('crypto');

Available algorithms

List supported algorithms with crypto.ALGORITHM.

1console.log(crypto.ALGORITHM);
2// -> ED25519, ECDSA_P256_SHA1, ECDSA_P256_SHA256, ECDSA_P256_SHA512, HMAC_SHA1, HMAC_SHA256, HMAC_SHA512

HMAC

Generate an HMAC signature with hmac(). Output is Base64‑encoded.

Usage: hmac(key, msg, algorithm)

• key: signature key
• msg: message to sign
• algorithm: one of crypto.ALGORITHM.HMAC_*

1crypto.hmac(base64.btoa('sharedSecretKey'), 'secretPayload', crypto.ALGORITHM.HMAC_SHA1).then((result) => {
2    console.log(result.replace('-', '+').replace('_', '/'));
3}).catch((error) => {
4    console.log(error)
5});

SHA‑1

Create a SHA‑1 hash with sha1().

Usage: sha1(msg)

• msg: message to hash

1crypto.sha1('secretPayload').then((result2) => {
2    console.log("secretPayload:" + result2);
3}).catch((error) => {
4    console.log(error)
5});

SHA‑256

Create a SHA‑256 hash with sha256().

Usage: sha256(msg)

• msg: message to hash

1crypto.sha256('secretPayload').then((result2) => {
2    console.log("secretPayload:" + result2);
3}).catch((error) => {
4    console.log(error)
5});

SHA‑512

Create a SHA‑512 hash with sha512().

Usage: sha512(msg)

• msg: message to hash

1crypto.sha512('secretPayload').then((result2) => {
2    console.log("secretPayload:" + result2);
3}).catch((error) => {
4    console.log(error)
5});

Private and public key examples

1const secretKey_ed25519 = {
2    'kty'   : 'EdDSA',
3    'crv'   : 'Ed25519',
4    'sk'    : 'bfk0DBOMwYi1_kRk66o_f8IGotVcNDRwfnTJ_ATiDrs',
5    'use'   : 'sig',
6};
7const publicKey_ed25519 = {
8    'kty'   : 'EdDSA',
9    'crv'   : 'Ed25519',
10    'pk'    : 'wNrBAsRTMYbiXcQxKEcjU-qr24eLFSrrjgAfktkCM6c',
11    'use'   : 'sig',
12};

Sign

Sign a message with a key and algorithm using sign().

Usage: sign(key, msg, algorithm)

• key: private key for signing
• msg: message to sign
• algorithm: one of crypto.ALGORITHM.*

1crypto.sign(privateKey, 'secretPayload', crypto.ALGORITHM.ECDSA_P256_SHA1).then((result4) => {
2    console.log(result4);
3}).catch((error) => {
4    console.log(error)
5});

Verify

Verify a signature with verify().

Usage: verify(sig, key, msg, algorithm)

• sig: existing signature
• key: public key for verification
• msg: original message
• algorithm: one of crypto.ALGORITHM.*

1crypto.verify(<existing_signature>, publicKey, 'secretPayload', crypto.ALGORITHM.ECDSA_P256_SHA1).then((results) => {
2    console.log(results)
3}).catch((error) => {
4    console.log(error)
5});

Functions support

If you need help with a scenario not covered here, contact PubNub Support.