crypto

The crypto built-in module is available only inside a PubNub Function. Its asynchronous methods hash, sign, and verify values.

1const crypto = require('crypto');

ALGORITHM

crypto.ALGORITHM lists the supported algorithms: ED25519, ECDSA_P256_SHA1, ECDSA_P256_SHA256, ECDSA_P256_SHA512, HMAC_SHA1, HMAC_SHA256, HMAC_SHA512.

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

hmac

hmac(key, msg, algorithm)

* required

Parameter	Description
key * Type: String	Signature key.
msg * Type: String	Message to sign.
algorithm * Type: String	One of crypto.ALGORITHM.HMAC_*.

Returns: Promise resolving to a Base64-encoded HMAC signature.

1const crypto = require('crypto');
2const base64 = require('codec/base64');
3crypto.hmac(base64.btoa('sharedSecretKey'), 'secretPayload', crypto.ALGORITHM.HMAC_SHA1).then((result) => {
4    console.log(result);
5}).catch((error) => {
6    console.log(error);
7});

sha1, sha256, sha512

sha1(msg), sha256(msg), sha512(msg)

* required

Parameter	Description
msg * Type: String	Message to hash.

Returns: Promise resolving to the hash of msg.

1const crypto = require('crypto');
2crypto.sha256('secretPayload').then((result) => {
3    console.log('secretPayload:' + result);
4}).catch((error) => {
5    console.log(error);
6});

sign

sign(key, msg, algorithm)

* required

Parameter	Description
key * Type: Object	Private key for signing.
msg * Type: String	Message to sign.
algorithm * Type: String	One of crypto.ALGORITHM.*.

Returns: Promise resolving to the signature.

A private or public key for ED25519 takes this shape:

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};

1const crypto = require('crypto');
2crypto.sign(privateKey, 'secretPayload', crypto.ALGORITHM.ECDSA_P256_SHA1).then((result) => {
3    console.log(result);
4}).catch((error) => {
5    console.log(error);
6});

verify

verify(sig, key, msg, algorithm)

* required

Parameter	Description
sig * Type: String	Signature to verify.
key * Type: Object	Public key for verification.
msg * Type: String	Original message.
algorithm * Type: String	One of crypto.ALGORITHM.*.

Returns: Promise resolving to the verification result.

1const crypto = require('crypto');
2crypto.verify(existingSignature, publicKey, 'secretPayload', crypto.ALGORITHM.ECDSA_P256_SHA1).then((result) => {
3    console.log(result);
4}).catch((error) => {
5    console.log(error);
6});

Related reference

• Modules and libraries. Every built-in module available inside a Function.
• codec. Base64 encoding used to prepare keys for hmac().