Add support for EC in the JWKS (#19320)

* Add support for EC in the JWKS

* Fix test evidence

sdk/libs-scala/jwt/src/main/scala/com/daml/jwt/JwksVerifier.scala

@@ -4,10 +4,11 @@
 package com.daml.jwt
 
 import java.net.{URI, URL}
-import java.security.interfaces.RSAPublicKey
+import java.security.interfaces.{ECPublicKey, RSAPublicKey}
 import java.util.concurrent.TimeUnit
 
-import com.auth0.jwk.UrlJwkProvider
+import com.auth0.jwk.{JwkException, UrlJwkProvider}
+import com.auth0.jwt.algorithms.Algorithm
 import com.google.common.cache.{Cache, CacheBuilder}
 import scalaz.{-\/, Show, \/}
 import scalaz.syntax.show._
@@ -56,9 +57,23 @@ class JwksVerifier(
     .build()
 
   private[this] def getVerifier(keyId: String): Error \/ JwtVerifier = {
+    try {
       val jwk = http.get(keyId)
-    val publicKey = jwk.getPublicKey.asInstanceOf[RSAPublicKey]
+      val publicKey = jwk.getPublicKey
-    RSA256Verifier(publicKey, jwtTimestampLeeway)
+      publicKey match {
+        case rsa: RSAPublicKey => RSA256Verifier(rsa, jwtTimestampLeeway)
+        case ec: ECPublicKey if ec.getParams.getCurve.getField.getFieldSize == 256 =>
+          ECDSAVerifier(Algorithm.ECDSA256(ec, null), jwtTimestampLeeway)
+        case ec: ECPublicKey if ec.getParams.getCurve.getField.getFieldSize == 521 =>
+          ECDSAVerifier(Algorithm.ECDSA512(ec, null), jwtTimestampLeeway)
+        case key =>
+          -\/(Error(Symbol("getVerifier"), s"Unsupported public key format ${key.getFormat}"))
+      }
+    } catch {
+      case e: JwkException => -\/(Error(Symbol("getVerifier"), s"Couldn't get jwk from http: $e"))
+      case _: Throwable =>
+        -\/(Error(Symbol("getVerifier"), s"Unknown error while getting jwk from http"))
+    }
   }
 
   /** Looks up the verifier for the given keyId from the local cache.

sdk/libs-scala/jwt/src/main/scala/com/daml/jwt/KeyUtils.scala

@@ -97,7 +97,7 @@ object KeyUtils {
       }
     } yield key
 
-  /** Generates a JWKS JSON object for the given map of KeyID->Key
+  /** Generates a JWKS JSON object for the given map of KeyID->Key for RSA
     *
     * Note: this uses the same format as Google OAuth, see https://www.googleapis.com/oauth2/v3/certs
     */
@@ -121,4 +121,33 @@ object KeyUtils {
        |}
     """.stripMargin
   }
+
+  /** Generates a JWKS JSON object for the given map of KeyID->Key for EC
+    *
+    * Note: this uses the same format as Google OAuth, see https://www.gstatic.com/iap/verify/public_key-jwk
+    */
+  def generateECJwks(keys: Map[String, ECPublicKey]): String = {
+    def generateKeyEntry(keyId: String, key: ECPublicKey): String =
+      s"""    {
+         |      "kid": "$keyId",
+         |      "kty": "EC",
+         |      "alg": "ES${key.getParams.getCurve.getField.getFieldSize}",
+         |      "use": "sig",
+         |      "crv": "P-${key.getParams.getCurve.getField.getFieldSize}",
+         |      "x": "${java.util.Base64.getUrlEncoder.encodeToString(
+          key.getW.getAffineX.toByteArray
+        )}",
+         |      "y": "${java.util.Base64.getUrlEncoder.encodeToString(
+          key.getW.getAffineY.toByteArray
+        )}"
+         |    }""".stripMargin
+
+    s"""
+       |{
+       |  "keys": [
+       |${keys.toList.map { case (keyId, key) => generateKeyEntry(keyId, key) }.mkString(",\n")}
+       |  ]
+       |}
+    """.stripMargin
+  }
 }

sdk/libs-scala/jwt/src/test/scala/com/daml/jwt/JwksSpec.scala

@@ -11,12 +11,14 @@ import org.scalatest.flatspec.AnyFlatSpec
 import org.scalatest.matchers.should.Matchers
 import scalaz.\/
 import scalaz.syntax.show._
+import java.security.{KeyPairGenerator, PrivateKey, PublicKey}
+import java.security.interfaces.{ECPrivateKey, ECPublicKey, RSAPrivateKey, RSAPublicKey}
+import java.security.spec.ECGenParameterSpec
 
-import java.security.KeyPairGenerator
+import com.auth0.jwt.algorithms.Algorithm
-import java.security.interfaces.{RSAPrivateKey, RSAPublicKey}
 import com.daml.http.test.SimpleHttpServer
 
-class JwksSpec extends AnyFlatSpec with Matchers {
+trait JwksSpec extends AnyFlatSpec with Matchers { self: JwksSpecKeys =>
 
   val securityAsset: SecurityTest =
     SecurityTest(property = Authenticity, asset = "JWKS-configured Resource")
@@ -27,16 +29,10 @@ class JwksSpec extends AnyFlatSpec with Matchers {
     mitigation = s"Refuse to verify authenticity of the token",
   )
 
-  private def generateToken(keyId: String, privateKey: RSAPrivateKey): JwtSigner.Error \/ Jwt = {
-    val jwtPayload = s"""{"test": "JwksSpec"}"""
-    val jwtHeader = s"""{"alg": "RS256", "typ": "JWT", "kid": "$keyId"}"""
-    JwtSigner.RSA256.sign(DecodedJwt(jwtHeader, jwtPayload), privateKey)
-  }
-
   it should "successfully verify against provided correct key by JWKS server" taggedAs securityAsset
     .setHappyCase(
       "Successfully verify against provided correct key by JWKS server"
-    ) in new JwksSpec.Scope {
+    ) in {
     val token = generateToken("test-key-1", privateKey1)
       .fold(e => fail("Failed to generate signed token: " + e.shows), x => x)
     val result = verifier.verify(token)
@@ -48,7 +44,7 @@ class JwksSpec extends AnyFlatSpec with Matchers {
   }
 
   it should "raise an error by verifying a token with an unknown key id" taggedAs securityAsset
-    .setAttack(attack(threat = "Present an unknown key-id")) in new JwksSpec.Scope {
+    .setAttack(attack(threat = "Present an unknown key-id")) in {
     val token = generateToken("test-key-unknown", privateKey1)
       .fold(e => fail("Failed to generate signed token: " + e.shows), x => x)
     val result = verifier.verify(token)
@@ -59,7 +55,7 @@ class JwksSpec extends AnyFlatSpec with Matchers {
   it should "raise an error by verifying a token with wrong public key" taggedAs securityAsset
     .setAttack(
       attack(threat = "Present a known key-id, but not the one used for the token encryption")
-    ) in new JwksSpec.Scope {
+    ) in {
     val token = generateToken("test-key-1", privateKey2)
       .fold(e => fail("Failed to generate signed token: " + e.shows), x => x)
     val result = verifier.verify(token)
@@ -71,32 +67,100 @@ class JwksSpec extends AnyFlatSpec with Matchers {
   }
 }
 
-object JwksSpec {
+trait JwksSpecKeys {
-  trait Scope {
-    // Generate some RSA key pairs
-    private val keySize = 2048
-    private val kpg = KeyPairGenerator.getInstance("RSA")
-    kpg.initialize(keySize)
 
+  protected type PublicKeyType <: PublicKey
+  protected type PrivateKeyType <: PrivateKey
+
+  protected def kpg: KeyPairGenerator
+  protected def jwks: String
+  protected def generateToken(keyId: String, privateKey: PrivateKeyType): JwtSigner.Error \/ Jwt
+
+  // Generate some RSA key pairs
   private val keyPair1 = kpg.generateKeyPair()
-    private val publicKey1 = keyPair1.getPublic.asInstanceOf[RSAPublicKey]
+  protected val publicKey1: PublicKeyType = keyPair1.getPublic.asInstanceOf[PublicKeyType]
-    val privateKey1 = keyPair1.getPrivate.asInstanceOf[RSAPrivateKey]
+  val privateKey1: PrivateKeyType = keyPair1.getPrivate.asInstanceOf[PrivateKeyType]
 
   private val keyPair2 = kpg.generateKeyPair()
-    private val publicKey2 = keyPair2.getPublic.asInstanceOf[RSAPublicKey]
+  protected val publicKey2: PublicKeyType = keyPair2.getPublic.asInstanceOf[PublicKeyType]
-    val privateKey2 = keyPair2.getPrivate.asInstanceOf[RSAPrivateKey]
+  val privateKey2: PrivateKeyType = keyPair2.getPrivate.asInstanceOf[PrivateKeyType]
 
-    // Start a JWKS server and create a verifier using the JWKS server
+  private val server = SimpleHttpServer.start(jwks)
-    private val jwks = KeyUtils.generateJwks(
+  private val url = SimpleHttpServer.responseUrl(server)
+
+  protected val verifier: JwksVerifier = JwksVerifier(url)
+}
+
+class JwksSpecRSA extends JwksSpec with JwksSpecKeys {
+
+  private val keySize = 2048
+
+  override type PublicKeyType = RSAPublicKey
+  override type PrivateKeyType = RSAPrivateKey
+
+  override def kpg: KeyPairGenerator = KeyPairGenerator.getInstance("RSA")
+  kpg.initialize(keySize)
+
+  override def jwks: String = KeyUtils.generateJwks(
     Map(
       "test-key-1" -> publicKey1,
       "test-key-2" -> publicKey2,
     )
   )
 
-    private val server = SimpleHttpServer.start(jwks)
+  override def generateToken(keyId: String, privateKey: PrivateKeyType): JwtSigner.Error \/ Jwt = {
-    private val url = SimpleHttpServer.responseUrl(server)
+    val jwtPayload = s"""{"test": "JwksSpec"}"""
+    val jwtHeader = s"""{"alg": "RS256", "typ": "JWT", "kid": "$keyId"}"""
+    JwtSigner.RSA256.sign(DecodedJwt(jwtHeader, jwtPayload), privateKey)
+  }
+}
 
-    val verifier = JwksVerifier(url)
+class JwksSpecES256 extends JwksSpec with JwksSpecKeys {
+
+  override type PublicKeyType = ECPublicKey
+  override type PrivateKeyType = ECPrivateKey
+
+  protected def kpg: KeyPairGenerator = {
+    val gen = KeyPairGenerator.getInstance("EC")
+    gen.initialize(new ECGenParameterSpec("secp256r1"))
+    gen
+  }
+
+  protected def jwks: String = KeyUtils.generateECJwks(
+    Map(
+      "test-key-1" -> publicKey1,
+      "test-key-2" -> publicKey2,
+    )
+  )
+
+  protected def generateToken(keyId: String, privateKey: PrivateKeyType): JwtSigner.Error \/ Jwt = {
+    val jwtPayload = s"""{"test": "JwksSpec"}"""
+    val jwtHeader = s"""{"alg": "ES256", "typ": "JWT", "kid": "$keyId"}"""
+    JwtSigner.ECDSA.sign(DecodedJwt(jwtHeader, jwtPayload), privateKey, Algorithm.ECDSA256(null, _))
+  }
+}
+
+class JwksSpecES512 extends JwksSpec with JwksSpecKeys {
+
+  override type PublicKeyType = ECPublicKey
+  override type PrivateKeyType = ECPrivateKey
+
+  protected def kpg: KeyPairGenerator = {
+    val gen = KeyPairGenerator.getInstance("EC")
+    gen.initialize(new ECGenParameterSpec("secp521r1"))
+    gen
+  }
+
+  protected def jwks: String = KeyUtils.generateECJwks(
+    Map(
+      "test-key-1" -> publicKey1,
+      "test-key-2" -> publicKey2,
+    )
+  )
+
+  protected def generateToken(keyId: String, privateKey: PrivateKeyType): JwtSigner.Error \/ Jwt = {
+    val jwtPayload = s"""{"test": "JwksSpec"}"""
+    val jwtHeader = s"""{"alg": "ES512", "typ": "JWT", "kid": "$keyId"}"""
+    JwtSigner.ECDSA.sign(DecodedJwt(jwtHeader, jwtPayload), privateKey, Algorithm.ECDSA512(null, _))
   }
 }

sdk/test-evidence/BUILD.bazel

@@ -41,6 +41,7 @@ write_scalatest_runpath(
             "//libs-scala/jwt:tests-lib",
         ],
         runtime_deps = [
+            "//libs-scala/http-test-utils",
             "//libs-scala/jwt",
             "//libs-scala/scalatest-utils",
         ],