hpke-js

For Node.js, you can install hpke-js via npm/yarn:

npm install @hpke/core
# if necessary...
npm install @hpke/dhkem-x25519
npm install @hpke/dhkem-x448
npm install @hpke/chacha20poly1305
# ...or you can use the v0.x-compatible all-in-one package below.
npm install hpke-js
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Then, you can use it as follows:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm,
  });
  // When using "@hpke/core", specify the cryptographic algorithm instances
  // as follows, instead of identities above.
  // const suite = new CipherSuite({
  //   kem: new DhkemP256HkdfSha256(),
  //   kdf: new HkdfSha256(),
  //   aead: new Aes128Gcm(),
  // });

  // A recipient generates a key pair.
  const rkp = await suite.kem.generateKeyPair();

  // A sender encrypts a message with the recipient public key.
  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
  });
  const ct = await sender.seal(new TextEncoder().encode("Hello world!"));

  // The recipient decrypts it.
  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
  });
  const pt = await recipient.open(ct);

  // Hello world!
  console.log(new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (e) {
  console.log("failed:", e.message);
}
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Index

• Packages
• Supported Features
• Supported Environments
• Warnings and Restrictions
• Installation
  • Node.js
  • Deno
  • Web Browsers
  • Cloudflare Workers
• Usage
  • Base mode - for web browsers, Node.js and Deno.
  • Base mode with Single-Shot APIs
  • Base mode with export-only AEAD
  • PSK mode
  • Auth mode
  • AuthPSK mode
• Contributing
• References

Packages

The hpke-js includes the following packages.

Supported Features

HPKE Modes

Key Encapsulation Machanisms (KEMs)

Key Derivation Functions (KDFs)

• (*1) The HKDF functions built in @hpke/core can derive keys of the same length as the hash size. If you want to derive keys longer than the hash size, use hpke-js.

Authenticated Encryption with Associated Data (AEAD) Functions

Supported Environments

• Web Browser: Web Cryptography API supported browsers
  • Confirmed: Chrome, Firefox, Edge, Safari, Opera, Vivaldi, Brave
• Node.js: 16.x, 17.x, 18.x, 19.x, 20.x
• Deno: 1.x (1.25-)
• Cloudflare Workers
• bun: 0.x (0.6.0-), 1.x

Warnings and Restrictions

• Although this library has been passed the following test vectors, it has not been formally audited.
  • RFC9180 official test vectors provided on github.com/cfrg/draft-irtf-cfrg-hpke
  • ECDH/X25519/X448 test vectors provided on Project Wycheproof
• The upper limit of the AEAD sequence number is further rounded to JavaScript's MAX_SAFE_INTEGER (2^53-1).

Installation

Node.js

Using npm:

npm install @hpke/core
# if necessary...
npm install @hpke/dhkem-x25519
npm install @hpke/dhkem-x448
npm install @hpke/chacha20poly1305
# ...or you can use the v0.x-compatible all-in-one package below.
npm install hpke-js
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Using yarn:

yarn add @hpke/core
# if necessary...
yarn add @hpke/dhkem-x25519
yarn add @hpke/dhkem-x448
yarn add @hpke/chacha20poly1305
# ...or you can use the v0.x-compatible all-in-one package below.
yarn add hpke-js
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Deno

Using deno.land:

// use a specific version
import * as hpke from "https://deno.land/x/hpke@1.2.7/mod.ts";
// import * as hpke from "https://deno.land/x/hpke@1.2.7/core/mod.ts";
// import * as hpke from "https://deno.land/x/hpke@1.2.7/x/dhkem-x25519/mod.ts";

// use the latest stable version
import * as hpke from "https://deno.land/x/hpke/mod.ts";
// import * as hpke from "https://deno.land/x/hpke/core/mod.ts";
// import * as hpke from "https://deno.land/x/hpke/x/dhkem-x25519/mod.ts";
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Web Browsers

Followings are how to use the module with typical CDNs. Other CDNs can be used as well.

Using esm.sh:

<!-- use a specific version -->
<script type="module">
  import * as hpke from "https://esm.sh/hpke-js@1.2.7";
  // import * as hpke from "https://esm.sh/@hpke/core@1.2.7";
  // ...
</script>

<!-- use the latest stable version -->
<script type="module">
  import * as hpke from "https://esm.sh/hpke-js";
  // import * as hpke from "https://esm.sh/@hpke/core";
  // ...
</script>
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Using unpkg:

<!-- use a specific version -->
<script type="module">
  import * as hpke from "https://unpkg.com/hpke-js@1.2.7/esm/mod.js";
  // import * as hpke from "https://unpkg.com/@hpke/core@1.2.7/esm/mod.js";
  // ...
</script>
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Cloudflare Workers

git clone git@github.com:dajiaji/hpke-js.git
cd hpke-js
# for hpke-js
npm install -g esbuild
deno task dnt
deno task minify > $YOUR_SRC_PATH/hpke.js

# for @hpke/core
cd hpke-js/core
npm install -g esbuild
deno task dnt
deno task minify > $YOUR_SRC_PATH/hpke-core.js

# for @hpke/dhkem-x25519
cd hpke-js/x/dhkem-x25519
npm install -g esbuild
deno task dnt
deno task minify > $YOUR_SRC_PATH/hpke-dhkem-x25519.js
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Usage

This section shows some typical usage examples.

Base mode

Node.js:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm,
  });

  // A recipient generates a key pair.
  const rkp = await suite.kem.generateKeyPair();

  // A sender encrypts a message with the recipient public key.
  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
  });
  const ct = await sender.seal(new TextEncoder().encode("Hello world!"));

  // The recipient decrypts it.
  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
  });
  const pt = await recipient.open(ct);

  // Hello world!
  console.log("decrypted: ", new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (e) {
  console.log("failed:", e.message);
}
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Deno:

import { AeadId, CipherSuite, KdfId, KemId } from "https://deno.land/x/hpke@1.2.7/mod.ts";
// import {
//   Aes128Gcm, CipherSuite, HkdfSha256,
// } from "https://deno.land/x/hpke@1.2.7/core/mod.ts";
// import { DhkemX25519HkdfSha256 } from "https://deno.land/x/hpke@1.2.7/x/dhkem-x25519/mod.ts";

async function doHpke() {
  // setup
  const suite = new CipherSuite({
    // When using "https://deno.land/x/hpke/mod.ts" (not "/x/hpke/core/mod.ts"),
    // you can specify the identifier as follows:
    kem: KemId.DhkemX25519HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm,
  });
  //// When using hpke/core/mod.ts, specify the instances as follows:
  //const suite = new CipherSuite({
  //  kem: new DhkemX25519HkdfSha256(),
  //  kdf: new HkdfSha256(),
  //  aead: new Aes128Gcm(),
  //});

  const rkp = await suite.kem.generateKeyPair();

  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
  });

  // A JWK-formatted recipient public key can also be used.
  // const jwkPkR = {
  //   kty: "EC",
  //   crv: "P-256",
  //   kid: "P-256-01",
  //   x: "-eZXC6nV-xgthy8zZMCN8pcYSeE2XfWWqckA2fsxHPc",
  //   y: "BGU5soLgsu_y7GN2I3EPUXS9EZ7Sw0qif-V70JtInFI",
  //   key_ops: [],
  // };
  // const pkR = await suite.kem.importKey("jwk", jwkPkR, true);
  // const sender = await suite.createSenderContext({
  //   recipientPublicKey: pkR,
  // });

  // encrypt
  const ct = await sender.seal(new TextEncoder().encode("Hello world!"));

  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
  });

  // A JWK-formatted recipient private key can also be used.
  // const jwkSkR = {
  //   kty: "EC",
  //   crv: "P-256",
  //   kid: "P-256-01",
  //   x: "-eZXC6nV-xgthy8zZMCN8pcYSeE2XfWWqckA2fsxHPc",
  //   y: "BGU5soLgsu_y7GN2I3EPUXS9EZ7Sw0qif-V70JtInFI",
  //   d: "kwibx3gas6Kz1V2fyQHKSnr-ybflddSjN0eOnbmLmyo",
  //   key_ops: ["deriveBits"],
  // };
  // const skR = await suite.kem.importKey("jwk", jwkSkR, false);
  // const recipient = await suite.createRecipientContext({
  //   recipientKey: skR,
  //   enc: sender.enc,
  // });

  // decrypt
  const pt = await recipient.open(ct);

  // Hello world!
  console.log(new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (_err: unknown) {
  console.log("failed.");
}
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Browsers:

<html>
  <head></head>
  <body>
    <script type="module">
      import { AeadId, CipherSuite, KdfId, KemId } from "https://esm.sh/hpke-js@1.2.7";
      // import {
      //   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
      // } from "@hpke/core@1.2.7";

      globalThis.doHpke = async () => {
        try {
          const suite = new CipherSuite({
            kem: KemId.DhkemP256HkdfSha256,
            kdf: KdfId.HkdfSha256,
            aead: AeadId.Aes128Gcm
          });
 
          const rkp = await suite.kem.generateKeyPair();
      
          const sender = await suite.createSenderContext({
            recipientPublicKey: rkp.publicKey
          });
      
          // encrypt
          const ct = await sender.seal(new TextEncoder().encode("Hello world!"));


          const recipient = await suite.createRecipientContext({
            recipientKey: rkp.privateKey, // rkp (CryptoKeyPair) is also acceptable.
            enc: sender.enc,
          });

          // decrypt
          const pt = await recipient.open(ct);

          // Hello world!
          alert(new TextDecoder().decode(pt));
        } catch (err) {
          alert("failed:", err.message);
        }
      }
      
    </script>
    <button type="button" onclick="doHpke()">do HPKE</button>
  </body>
</html>
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Base mode with Single-Shot APIs

Node.js:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {

  // setup
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm
  });

  const rkp = await suite.kem.generateKeyPair();
  const pt = new TextEncoder().encode('Hello world!'),

  // encrypt
  const { ct, enc } = await suite.seal({ recipientPublicKey: rkp.publicKey }, pt);

  // decrypt
  const pt = await suite.open({ recipientKey: rkp.privateKey, enc: enc }, ct);

  // Hello world!
  console.log(new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (err) {
  console.log("failed:", err.message);
}
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Base mode with export-only AEAD

Node.js:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   CipherSuite, DhkemP256HkdfSha256, ExportOnly, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {
  // setup
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.ExportOnly,
  });
  // When using "@hpke/core",
  const suite = new CipherSuite({
    kem: new DhkemP256HkdfSha256(),
    kdf: new HkdfSha256(),
    aead: new ExportOnly(),
  });

  const rkp = await suite.kem.generateKeyPair();

  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
  });

  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
  });

  const te = new TextEncoder();

  // export
  const pskS = sender.export(te.encode("jugemujugemu"), 32);
  const pskR = recipient.export(te.encode("jugemujugemu"), 32);
  // pskR === pskS
}

try {
  doHpke();
} catch (err) {
  console.log("failed:", err.message);
}
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PSK mode

Node.js:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {
  // setup
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm,
  });

  const rkp = await suite.kem.generateKeyPair();

  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
    psk: {
      id: new TextEncoder().encode("our-pre-shared-key-id"),
      // a PSK MUST have at least 32 bytes.
      key: new TextEncoder().encode("jugemujugemugokounosurikirekaija"),
    },
  });

  // encrypt
  const ct = await sender.seal(new TextEncoder().encode("Hello world!"));

  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
    psk: {
      id: new TextEncoder().encode("our-pre-shared-key-id"),
      // a PSK MUST have at least 32 bytes.
      key: new TextEncoder().encode("jugemujugemugokounosurikirekaija"),
    },
  });

  // decrypt
  const pt = await recipient.open(ct);

  // Hello world!
  console.log(new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (err) {
  console.log("failed:", err.message);
}
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Auth mode

Node.js:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {
  // setup
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm,
  });

  const rkp = await suite.kem.generateKeyPair();
  const skp = await suite.kem.generateKeyPair();

  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
    senderKey: skp,
  });

  // encrypt
  const ct = await sender.seal(new TextEncoder().encode("Hello world!"));

  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
    senderPublicKey: skp.publicKey,
  });

  // decrypt
  const pt = await recipient.open(ct);

  // Hello world!
  console.log(new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (err) {
  console.log("failed:", err.message);
}
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AuthPSK mode

Node.js:

import { AeadId, CipherSuite, KdfId, KemId } from "hpke-js";
// const { AeadId, CipherSuite, KdfId, KemId } = require("hpke-js");
// import {
//   Aes128Gcm, CipherSuite, DhkemP256HkdfSha256, HkdfSha256,
// } from "@hpke/core";

async function doHpke() {
  // setup
  const suite = new CipherSuite({
    kem: KemId.DhkemP256HkdfSha256,
    kdf: KdfId.HkdfSha256,
    aead: AeadId.Aes128Gcm,
  });

  const rkp = await suite.kem.generateKeyPair();
  const skp = await suite.kem.generateKeyPair();

  const sender = await suite.createSenderContext({
    recipientPublicKey: rkp.publicKey,
    senderKey: skp,
    psk: {
      id: new TextEncoder().encode("our-pre-shared-key-id"),
      // a PSK MUST have at least 32 bytes.
      key: new TextEncoder().encode("jugemujugemugokounosurikirekaija"),
    },
  });

  // encrypt
  const ct = await sender.seal(new TextEncoder().encode("Hello world!"));

  const recipient = await suite.createRecipientContext({
    recipientKey: rkp.privateKey,
    enc: sender.enc,
    senderPublicKey: skp.publicKey,
    psk: {
      id: new TextEncoder().encode("our-pre-shared-key-id"),
      // a PSK MUST have at least 32 bytes.
      key: new TextEncoder().encode("jugemujugemugokounosurikirekaija"),
    },
  });

  // decrypt
  const pt = await recipient.open(ct);

  // Hello world!
  console.log(new TextDecoder().decode(pt));
}

try {
  doHpke();
} catch (err) {
  console.log("failed:", err.message);
}
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Contributing

We welcome all kind of contributions, filing issues, suggesting new features or sending PRs.

References

• RFC9180: Hybrid Public Key Encryption
• W3C/WICG: Secure Curves in the Web Cryptography API