From 97243df1032f3c9312ff3c0f741eb5b31489ef69 Mon Sep 17 00:00:00 2001
From: Filip Skokan <filip.skokan@okta.com>
Date: Wed, 11 Sep 2024 13:35:01 +0200
Subject: [PATCH] feat: add support for curve secp256k1 (ES256K)

---
 lib/oneShotAlgs.js                   | 5 +++++
 lib/validateAsymmetricKey.js         | 3 ++-
 sign.js                              | 2 +-
 test/jwt.asymmetric_signing.tests.js | 5 +++++
 test/roundtrip.test.js               | 1 +
 test/schema.tests.js                 | 2 ++
 test/secp256k1-private.pem           | 5 +++++
 test/secp256k1-public-invalid.pem    | 4 ++++
 test/secp256k1-public.pem            | 4 ++++
 verify.js                            | 2 +-
 10 files changed, 30 insertions(+), 3 deletions(-)
 create mode 100644 test/secp256k1-private.pem
 create mode 100644 test/secp256k1-public-invalid.pem
 create mode 100644 test/secp256k1-public.pem

diff --git a/lib/oneShotAlgs.js b/lib/oneShotAlgs.js
index 2be1359..8e3550c 100644
--- a/lib/oneShotAlgs.js
+++ b/lib/oneShotAlgs.js
@@ -37,6 +37,11 @@ module.exports = function(alg, key) {
       digest: 'sha256',
       key: { key, dsaEncoding: 'ieee-p1363' },
     };
+  case 'ES256K':
+    return {
+      digest: 'sha256',
+      key: { key, dsaEncoding: 'ieee-p1363' },
+    };
   case 'ES384':
     return {
       digest: 'sha384',
diff --git a/lib/validateAsymmetricKey.js b/lib/validateAsymmetricKey.js
index 447bd91..77d5bf3 100644
--- a/lib/validateAsymmetricKey.js
+++ b/lib/validateAsymmetricKey.js
@@ -1,13 +1,14 @@
 const { ASYMMETRIC_KEY_DETAILS_SUPPORTED, RSA_PSS_KEY_DETAILS_SUPPORTED } = require('./flags');
 
 const allowedAlgorithmsForKeys = {
-  'ec': ['ES256', 'ES384', 'ES512'],
+  'ec': ['ES256', 'ES256K', 'ES384', 'ES512'],
   'rsa': ['RS256', 'PS256', 'RS384', 'PS384', 'RS512', 'PS512'],
   'rsa-pss': ['PS256', 'PS384', 'PS512']
 };
 
 const allowedCurves = {
   ES256: 'prime256v1',
+  ES256K: 'secp256k1',
   ES384: 'secp384r1',
   ES512: 'secp521r1',
 };
diff --git a/sign.js b/sign.js
index b80c6b5..a4d6284 100644
--- a/sign.js
+++ b/sign.js
@@ -13,7 +13,7 @@ const encodeBase64url = require('./lib/base64url');
 const SUPPORTED_ALGS = [
   'RS256', 'RS384', 'RS512',
   'PS256', 'PS384', 'PS512',
-  'ES256', 'ES384', 'ES512',
+  'ES256', 'ES256K', 'ES384', 'ES512',
   'HS256', 'HS384', 'HS512',
   'none',
 ];
diff --git a/test/jwt.asymmetric_signing.tests.js b/test/jwt.asymmetric_signing.tests.js
index dfd1d38..a0f8415 100644
--- a/test/jwt.asymmetric_signing.tests.js
+++ b/test/jwt.asymmetric_signing.tests.js
@@ -21,6 +21,11 @@ const algorithms = {
     pub_key: loadKey('ecdsa-public.pem'),
     invalid_pub_key: loadKey('ecdsa-public-invalid.pem')
   },
+  ES256K: {
+    priv_key: loadKey('secp256k1-private.pem'),
+    pub_key: loadKey('secp256k1-public.pem'),
+    invalid_pub_key: loadKey('secp256k1-public-invalid.pem')
+  },
   PS256: {
     pub_key: loadKey('pub.pem'),
     priv_key: loadKey('priv.pem'),
diff --git a/test/roundtrip.test.js b/test/roundtrip.test.js
index 0995c5f..2b3c263 100644
--- a/test/roundtrip.test.js
+++ b/test/roundtrip.test.js
@@ -11,6 +11,7 @@ for (const [alg, opts] of [
   ["RS256"],
   ["PS256"],
   ["ES256"],
+  ["ES256K"],
   ["ES384"],
   ["ES512"],
 ]) {
diff --git a/test/schema.tests.js b/test/schema.tests.js
index 0033ab4..6def721 100644
--- a/test/schema.tests.js
+++ b/test/schema.tests.js
@@ -7,6 +7,7 @@ describe('schema', function() {
   describe('sign options', function() {
     var cert_rsa_priv = fs.readFileSync(__dirname + '/rsa-private.pem');
     var cert_ecdsa_priv = fs.readFileSync(__dirname + '/ecdsa-private.pem');
+    var cert_secp256k1_priv = fs.readFileSync(__dirname + '/secp256k1-private.pem');
     var cert_secp384r1_priv = fs.readFileSync(__dirname + '/secp384r1-private.pem');
     var cert_secp521r1_priv = fs.readFileSync(__dirname + '/secp521r1-private.pem');
 
@@ -26,6 +27,7 @@ describe('schema', function() {
       sign({algorithm: 'PS384'}, cert_rsa_priv);
       sign({algorithm: 'PS512'}, cert_rsa_priv);
       sign({algorithm: 'ES256'}, cert_ecdsa_priv);
+      sign({algorithm: 'ES256K'}, cert_secp256k1_priv);
       sign({algorithm: 'ES384'}, cert_secp384r1_priv);
       sign({algorithm: 'ES512'}, cert_secp521r1_priv);
       sign({algorithm: 'HS256'}, 'superSecret');
diff --git a/test/secp256k1-private.pem b/test/secp256k1-private.pem
new file mode 100644
index 0000000..1d05b81
--- /dev/null
+++ b/test/secp256k1-private.pem
@@ -0,0 +1,5 @@
+-----BEGIN EC PRIVATE KEY-----
+MHQCAQEEIFg3x9PMwysC/B5iW1zUFqDUfNbgP77i71jEPhoce0OkoAcGBSuBBAAK
+oUQDQgAEUdPp6J0l51augh0A0sB14n2j69er1ZTkhfv+XY3CIU/SFK/BmIt0KfAX
+VF2KGowflLSKkySNnfR93uwnf7y1MQ==
+-----END EC PRIVATE KEY-----
diff --git a/test/secp256k1-public-invalid.pem b/test/secp256k1-public-invalid.pem
new file mode 100644
index 0000000..5a84eed
--- /dev/null
+++ b/test/secp256k1-public-invalid.pem
@@ -0,0 +1,4 @@
+-----BEGIN PUBLIC KEY-----
+MFYwEAYHKoZIzj0CAQYFK4EEAAoDQgAE7cjAbx1KnvP+g5lJQba/42ga/NL5rkIC
+rmuRulSLZ+X6oRvnxfhgDkQgkoJkNaqXR6vYE42kfbz5BOfIcNfkig==
+-----END PUBLIC KEY-----
diff --git a/test/secp256k1-public.pem b/test/secp256k1-public.pem
new file mode 100644
index 0000000..aaa8fc9
--- /dev/null
+++ b/test/secp256k1-public.pem
@@ -0,0 +1,4 @@
+-----BEGIN PUBLIC KEY-----
+MFYwEAYHKoZIzj0CAQYFK4EEAAoDQgAEUdPp6J0l51augh0A0sB14n2j69er1ZTk
+hfv+XY3CIU/SFK/BmIt0KfAXVF2KGowflLSKkySNnfR93uwnf7y1MQ==
+-----END PUBLIC KEY-----
diff --git a/verify.js b/verify.js
index fcd1739..de3f3e8 100644
--- a/verify.js
+++ b/verify.js
@@ -7,7 +7,7 @@ const validateAsymmetricKey = require('./lib/validateAsymmetricKey');
 const crypto = require("crypto");
 const oneShotAlgs = require('./lib/oneShotAlgs');
 
-const EC_KEY_ALGS = ['ES256', 'ES384', 'ES512'];
+const EC_KEY_ALGS = ['ES256', 'ES256K', 'ES384', 'ES512'];
 const RSA_KEY_ALGS = ['RS256', 'RS384', 'RS512', 'PS256', 'PS384', 'PS512'];
 const PUB_KEY_ALGS = [].concat(RSA_KEY_ALGS, EC_KEY_ALGS);
 const HS_ALGS = ['HS256', 'HS384', 'HS512'];