openpgp: Fix classification of unknown public key algorithms.

  - Conservatively consider unknown algorithms encryption- and
    signing-capable.

  - Fixes parsing of PKESK and Signature packets using unknown
    algorithms.

  - Fixes #722.

1 files changed, 8 insertions, 2 deletions

diff --git a/openpgp/src/types/mod.rs b/openpgp/src/types/mod.rs
index b3a9822e..e9d39801 100644
--- a/openpgp/src/types/mod.rs
+++ b/openpgp/src/types/mod.rs
@@ -151,7 +151,10 @@ impl PublicKeyAlgorithm {
                      | DSA
                      | ECDSA
                      | ElGamalEncryptSign
-                     | EdDSA)
+                     | EdDSA
+                     | Private(_)
+                     | Unknown(_)
+            )
         }
     }
 
@@ -174,7 +177,10 @@ impl PublicKeyAlgorithm {
                      | RSAEncrypt
                      | ElGamalEncrypt
                      | ECDH
-                     | ElGamalEncryptSign)
+                     | ElGamalEncryptSign
+                     | Private(_)
+                     | Unknown(_)
+            )
         }
     }