1 files changed, 15 insertions, 5 deletions

diff --git a/Data/OpenPGP.hs b/Data/OpenPGP.hs
index 3064dc5..bee718a 100644
--- a/Data/OpenPGP.hs
+++ b/Data/OpenPGP.hs
@@ -59,6 +59,8 @@ module Data.OpenPGP (
         MPI(..),
         find_key,
         fingerprint_material,
+        auto_fp_version,
+        fingerprint_materialv,
         SignatureOver(..),
         signatures,
         signature_issuer,
@@ -843,9 +845,17 @@ parse_packet 19 =
 -- Represent unsupported packets as their tag and literal bytes
 parse_packet tag = fmap (UnsupportedPacket tag) getRemainingByteString
 
+auto_fp_version :: Packet -> Word8
+auto_fp_version p | version p == 2  = 3
+                  | otherwise       = version p
+
+-- | Helper method for fingerprints and such
+fingerprint_material :: HasCallStack => Packet -> [B.ByteString]
+fingerprint_material p = fingerprint_materialv (auto_fp_version p) p
+
 -- | Helper method for fingerprints and such
-fingerprint_material :: Packet -> [B.ByteString]
-fingerprint_material p | version p == 5 =
+fingerprint_materialv :: HasCallStack => Word8 -> Packet -> [B.ByteString]
+fingerprint_materialv 5 p =
         [
                 B.singleton 0x9A,
                 encode (10 + fromIntegral (B.length material) :: Word32),
@@ -855,7 +865,7 @@ fingerprint_material p | version p == 5 =
         ]
         where
         material = B.concat $ encode_public_key_material p
-fingerprint_material p | version p == 4 =
+fingerprint_materialv 4 p =
         [
                 B.singleton 0x99,
                 encode (6 + fromIntegral (B.length material) :: Word16),
@@ -864,11 +874,11 @@ fingerprint_material p | version p == 4 =
         ]
         where
         material = B.concat $ encode_public_key_material p
-fingerprint_material p | version p `elem` [2, 3] = [n, e]
+fingerprint_materialv 3 p | key_algorithm p == RSA = [n, e]
         where
         n = B.drop 2 (encode (key p ! 'n'))
         e = B.drop 2 (encode (key p ! 'e'))
-fingerprint_material _ =
+fingerprint_materialv _ _ =
         error "Unsupported Packet version or type in fingerprint_material."
 
 enum_to_word8 :: (Enum a) => a -> Word8