PublicKeyAlgorithm: Ask PublicKeyUtils for algorithm capabilities, add persistent symmetric key algorithm ids

pgpainless-core/src/main/kotlin/org/pgpainless/algorithm/PublicKeyAlgorithm.kt

@@ -4,19 +4,17 @@
 
 package org.pgpainless.algorithm
 
+import org.bouncycastle.bcpg.PublicKeyUtils
+
 /**
  * Enumeration of public key algorithms as defined in RFC4880.
  *
  * See [RFC4880: Public-Key Algorithms](https://tools.ietf.org/html/rfc4880#section-9.1)
  */
-enum class PublicKeyAlgorithm(
-    val algorithmId: Int,
-    val signingCapable: Boolean,
-    val encryptionCapable: Boolean
-) {
+enum class PublicKeyAlgorithm(val algorithmId: Int) {
 
     /** RSA capable of encryption and signatures. */
-    RSA_GENERAL(1, true, true),
+    RSA_GENERAL(1),
 
     /**
      * RSA with usage encryption.
@@ -25,7 +23,7 @@ enum class PublicKeyAlgorithm(
      *   notice</a>
      */
     @Deprecated("RSA_ENCRYPT is deprecated in favor of RSA_GENERAL", ReplaceWith("RSA_GENERAL"))
-    RSA_ENCRYPT(2, false, true),
+    RSA_ENCRYPT(2),
 
     /**
      * RSA with usage of creating signatures.
@@ -34,19 +32,19 @@ enum class PublicKeyAlgorithm(
      *   notice</a>
      */
     @Deprecated("RSA_SIGN is deprecated in favor of RSA_GENERAL", ReplaceWith("RSA_GENERAL"))
-    RSA_SIGN(3, true, false),
+    RSA_SIGN(3),
 
     /** ElGamal with usage encryption. */
-    ELGAMAL_ENCRYPT(16, false, true),
+    ELGAMAL_ENCRYPT(16),
 
     /** Digital Signature Algorithm. */
-    DSA(17, true, false),
+    DSA(17),
 
     /** Elliptic Curve Diffie-Hellman. */
-    ECDH(18, false, true),
+    ECDH(18),
 
     /** Elliptic Curve Digital Signature Algorithm. */
-    ECDSA(19, true, false),
+    ECDSA(19),
 
     /**
      * ElGamal General.
@@ -54,26 +52,50 @@ enum class PublicKeyAlgorithm(
      * @deprecated see <a href="https://tools.ietf.org/html/rfc4880#section-13.8">Deprecation
      *   notice</a>
      */
-    @Deprecated("ElGamal is deprecated") ELGAMAL_GENERAL(20, true, true),
+    @Deprecated("ElGamal is deprecated") ELGAMAL_GENERAL(20),
 
     /** Diffie-Hellman key exchange algorithm. */
-    DIFFIE_HELLMAN(21, false, true),
+    DIFFIE_HELLMAN(21),
 
     /** Digital Signature Algorithm based on twisted Edwards Curves. */
-    EDDSA_LEGACY(22, true, false),
+    EDDSA_LEGACY(22),
 
     /** X25519 encryption algorithm. */
-    X25519(25, false, true),
+    X25519(25),
 
     /** X448 encryption algorithm. */
-    X448(26, false, true),
+    X448(26),
 
     /** Ed25519 signature algorithm. */
-    ED25519(27, true, false),
+    ED25519(27),
 
     /** Ed448 signature algorithm. */
-    ED448(28, true, false),
-    ;
+    ED448(28),
+
+    /**
+     * AEAD can be used as a persistent key symmetric encryption algorithm for message encryption.
+     *
+     * @see
+     *   [Persistent Symmetric Keys in OpenPGP](https://datatracker.ietf.org/doc/draft-ietf-openpgp-persistent-symmetric-keys/)
+     */
+    AEAD(128) {
+        override val signingCapable = false
+        override val encryptionCapable = true
+    },
+
+    /**
+     * HMAC can be used as a persistent key symmetric signing algorithm for message signing.
+     *
+     * @see
+     *   [Persistent Symmetric Keys in OpenPGP](https://datatracker.ietf.org/doc/draft-ietf-openpgp-persistent-symmetric-keys/)
+     */
+    HMAC(129) {
+        override val signingCapable = true
+        override val encryptionCapable = false
+    };
+
+    open val signingCapable: Boolean = PublicKeyUtils.isSigningAlgorithm(algorithmId)
+    open val encryptionCapable: Boolean = PublicKeyUtils.isEncryptionAlgorithm(algorithmId)
 
     fun isSigningCapable(): Boolean = signingCapable