feat: add support for secp256k1 keys through the libp2p-crypto-secp256k1 module

README.md

@@ -107,9 +107,21 @@ Depending on the environment this is either an instance of [node-webcrypto-ossl]
 
 ### `keys`
 
+#### Supported Key Types
+
+The [`generateKeyPair`](#generatekeypairtype-bits-callback), [`marshalPublicKey`](#marshalpublickeykey-type-callback), and
+[`marshalPrivateKey`](#marshalprivatekeykey-type) functions accept a string `type` argument.
+
+Currently the `'RSA'` and `'ed25519'` types are supported, although ed25519 keys support only signing and
+verification of messages.  For encryption / decryption support, RSA keys should be used.
+
+Installing the [libp2p-crypto-secp256k1](https://github.com/libp2p/js-libp2p-crypto-secp256k1) module adds support for the
+`'secp256k1'` type, which supports ECDSA signatures using the secp256k1 elliptic curve popularized by Bitcoin.  This module
+is not installed by default, and should be explicitly depended on if your project requires secp256k1 support.
+
 ### `generateKeyPair(type, bits, callback)`
 
-- `type: String`, only `'RSA'` is currently supported
+- `type: String`, see [Supported Key Types](#supported-key-types) above.
 - `bits: Number` Minimum of 1024
 - `callback: Function`
 
@@ -160,8 +172,8 @@ Calls back with an object of the form
 
 ### `marshalPublicKey(key[, type], callback)`
 
-- `key: crypto.rsa.RsaPublicKey`
+- `key: keys.rsa.RsaPublicKey | keys.ed25519.Ed25519PublicKey | require('libp2p-crypto-secp256k1').Secp256k1PublicKey`
-- `type: String`, only `'RSA'` is currently supported
+- `type: String`, see [Supported Key Types](#supported-key-types) above.
 
 Converts a public key object into a protobuf serialized public key.
 
@@ -173,8 +185,8 @@ Converts a protobuf serialized public key into its  representative object.
 
 ### `marshalPrivateKey(key[, type])`
 
-- `key: crypto.rsa.RsaPrivateKey`
+- `key: keys.rsa.RsaPrivateKey | keys.ed25519.Ed25519PrivateKey | require('libp2p-crypto-secp256k1').Secp256k1PrivateKey`
-- `type: String`, only `'RSA'` is currently supported
+- `type: String`, see [Supported Key Types](#supported-key-types) above.
 
 Converts a private key object into a protobuf serialized private key.
 

package.json

@@ -80,4 +80,4 @@
     "dryajov <dryajov@gmail.com>",
     "nikuda <nikuda@gmail.com>"
   ]
-}
+}

src/crypto.proto.js

@@ -3,6 +3,7 @@
 module.exports = `enum KeyType {
   RSA = 0;
   Ed25519 = 1;
+  Secp256k1 = 2;
 }
 
 message PublicKey {

src/index.js

@@ -10,7 +10,10 @@ exports.aes = c.aes
 exports.webcrypto = c.webcrypto
 
 const keys = exports.keys = require('./keys')
-const KEY_TYPES = ['rsa', 'ed25519']
+function isValidKeyType (keyType) {
+  const key = keys[keyType.toLowerCase()]
+  return key !== undefined
+}
 
 exports.keyStretcher = require('./key-stretcher')
 exports.generateEphemeralKeyPair = require('./ephemeral-keys')
@@ -35,6 +38,12 @@ exports.unmarshalPublicKey = (buf) => {
       return keys.rsa.unmarshalRsaPublicKey(decoded.Data)
     case pbm.KeyType.Ed25519:
       return keys.ed25519.unmarshalEd25519PublicKey(decoded.Data)
+    case pbm.KeyType.Secp256k1:
+      if (keys.secp256k1) {
+        return keys.secp256k1.unmarshalSecp256k1PublicKey(decoded.Data)
+      } else {
+        throw new Error('secp256k1 support requires libp2p-crypto-secp256k1 package')
+      }
     default:
       throw new Error('invalid or unsupported key type')
   }
@@ -43,7 +52,7 @@ exports.unmarshalPublicKey = (buf) => {
 // Converts a public key object into a protobuf serialized public key
 exports.marshalPublicKey = (key, type) => {
   type = (type || 'rsa').toLowerCase()
-  if (KEY_TYPES.indexOf(type) < 0) {
+  if (!isValidKeyType(type)) {
     throw new Error('invalid or unsupported key type')
   }
 
@@ -60,6 +69,12 @@ exports.unmarshalPrivateKey = (buf, callback) => {
       return keys.rsa.unmarshalRsaPrivateKey(decoded.Data, callback)
     case pbm.KeyType.Ed25519:
       return keys.ed25519.unmarshalEd25519PrivateKey(decoded.Data, callback)
+    case pbm.KeyType.Secp256k1:
+      if (keys.secp256k1) {
+        return keys.secp256k1.unmarshalSecp256k1PrivateKey(decoded.Data, callback)
+      } else {
+        return callback(new Error('secp256k1 support requires libp2p-crypto-secp256k1 package'))
+      }
     default:
       callback(new Error('invalid or unsupported key type'))
   }
@@ -68,7 +83,7 @@ exports.unmarshalPrivateKey = (buf, callback) => {
 // Converts a private key object into a protobuf serialized private key
 exports.marshalPrivateKey = (key, type) => {
   type = (type || 'rsa').toLowerCase()
-  if (KEY_TYPES.indexOf(type) < 0) {
+  if (!isValidKeyType(type)) {
     throw new Error('invalid or unsupported key type')
   }
 

src/keys/index.js

@@ -4,3 +4,8 @@ module.exports = {
   rsa: require('./rsa'),
   ed25519: require('./ed25519')
 }
+
+try {
+  module.exports.secp256k1 = require('libp2p-crypto-secp256k1')
+} catch (err) {
+}

test/fixtures/secp256k1.js

@@ -0,0 +1,11 @@
+'use strict'
+
+const Buffer = require('safe-buffer').Buffer
+
+module.exports = {
+
+  // protobuf marshaled key pair generated with libp2p-crypto-secp256k1
+  // and marshaled with libp2p-crypto.marshalPublicKey / marshalPrivateKey
+  pbmPrivateKey: Buffer.from('08021220e0600103010000000100000000000000be1dc82c2e000000e8d6030301000000', 'hex'),
+  pbmPublicKey: Buffer.from('0802122103a9a7272a726fa083abf31ba44037f8347fbc5e5d3113d62a7c6bc26752fd8ee1', 'hex')
+}

test/index.spec.js

@@ -23,9 +23,17 @@ describe('libp2p-crypto', () => {
     const key2 = crypto.unmarshalPublicKey(crypto.marshalPublicKey(key.public))
 
     expect(key2.equals(key.public)).to.be.eql(true)
+
+    expect(() => {
+      crypto.marshalPublicKey(key.public, 'invalid-key-type')
+    }).to.throw()
   })
 
   it('marshalPrivateKey and unmarshalPrivateKey', (done) => {
+    expect(() => {
+      crypto.marshalPrivateKey(key, 'invalid-key-type')
+    }).to.throw()
+
     crypto.unmarshalPrivateKey(crypto.marshalPrivateKey(key), (err, key2) => {
       if (err) {
         return done(err)
@@ -103,7 +111,7 @@ describe('libp2p-crypto', () => {
     it('throws with no number passed', () => {
       expect(() => {
         crypto.randomBytes()
-      }).to.throw
+      }).to.throw()
     })
 
     it('generates different random things', () => {

test/secp256k1.spec.js

@@ -0,0 +1,104 @@
+/* eslint-env mocha */
+'use strict'
+
+const expect = require('chai').expect
+const fixtures = require('./fixtures/secp256k1')
+const crypto = require('../src')
+
+const mockPublicKey = {
+  bytes: fixtures.pbmPublicKey
+}
+
+const mockPrivateKey = {
+  bytes: fixtures.pbmPrivateKey,
+  public: mockPublicKey
+}
+
+const mockSecp256k1Module = {
+  generateKeyPair (bits, callback) {
+    callback(null, mockPrivateKey)
+  },
+
+  unmarshalSecp256k1PrivateKey (buf, callback) {
+    callback(null, mockPrivateKey)
+  },
+
+  unmarshalSecp256k1PublicKey (buf) {
+    return mockPublicKey
+  }
+}
+
+describe('with libp2p-crypto-secp256k1 module present', () => {
+  let key
+
+  before((done) => {
+    crypto.keys['secp256k1'] = mockSecp256k1Module
+    crypto.generateKeyPair('secp256k1', 256, (err, _key) => {
+      if (err) return done(err)
+      key = _key
+      done()
+    })
+  })
+
+  after((done) => {
+    delete crypto.keys['secp256k1']
+    done()
+  })
+
+  it('generates a valid key', (done) => {
+    expect(
+      key
+    ).to.exist
+    done()
+  })
+
+  it('protobuf encoding', (done) => {
+    const keyMarshal = crypto.marshalPrivateKey(key)
+    crypto.unmarshalPrivateKey(keyMarshal, (err, key2) => {
+      if (err) return done(err)
+      const keyMarshal2 = crypto.marshalPrivateKey(key2)
+
+      expect(
+        keyMarshal
+      ).to.be.eql(
+        keyMarshal2
+      )
+
+      const pk = key.public
+      const pkMarshal = crypto.marshalPublicKey(pk)
+      const pk2 = crypto.unmarshalPublicKey(pkMarshal)
+      const pkMarshal2 = crypto.marshalPublicKey(pk2)
+
+      expect(
+        pkMarshal
+      ).to.be.eql(
+        pkMarshal2
+      )
+      done()
+    })
+  })
+})
+
+describe('without libp2p-crypto-secp256k1 module present', () => {
+  it('fails to generate a secp256k1 key', (done) => {
+    crypto.generateKeyPair('secp256k1', 256, (err, key) => {
+      expect(err).to.exist
+      expect(key).to.not.exist
+      done()
+    })
+  })
+
+  it('fails to unmarshal a secp256k1 private key', (done) => {
+    crypto.unmarshalPrivateKey(fixtures.pbmPrivateKey, (err, key) => {
+      expect(err).to.exist
+      expect(key).to.not.exist
+      done()
+    })
+  })
+
+  it('fails to unmarshal a secp256k1 public key', () => {
+    expect(() => {
+      crypto.unmarshalPublicKey(fixtures.pbmPublicKey)
+    }).to.throw(Error)
+  })
+})