move find_key logit out of Crypto

1 files changed, 18 insertions, 1 deletions

diff --git a/Data/OpenPGP.hs b/Data/OpenPGP.hs
index 7d421dc..99f241b 100644
--- a/Data/OpenPGP.hs
+++ b/Data/OpenPGP.hs
@@ -47,6 +47,7 @@ module Data.OpenPGP (
         KeyAlgorithm(..),
         CompressionAlgorithm(..),
         MPI(..),
+        find_key,
         fingerprint_material,
         signatures_and_data,
         signature_issuer,
@@ -676,7 +677,23 @@ encode_s2k_count iterations
                 | count < 32 = (count, c)
                 | otherwise = encode_s2k_count' (count `shiftR` 1) (c+1)
 
--- SignaturePacket smart constructor
+find_key :: (Packet -> String) -> Message -> String -> Maybe Packet
+find_key fpr (Message (x@(PublicKeyPacket {}):xs)) keyid =
+        find_key' fpr x xs keyid
+find_key fpr (Message (x@(SecretKeyPacket {}):xs)) keyid =
+        find_key' fpr x xs keyid
+find_key fpr (Message (_:xs)) keyid =
+        find_key fpr (Message xs) keyid
+find_key _ _ _ = Nothing
+
+find_key' :: (Packet -> String) -> Packet -> [Packet] -> String -> Maybe Packet
+find_key' fpr x xs keyid
+        | thisid == keyid = Just x
+        | otherwise = find_key fpr (Message xs) keyid
+        where
+        thisid = reverse $ take (length keyid) (reverse (fpr x))
+
+-- | SignaturePacket smart constructor
 signaturePacket :: Word8 -> Word8 -> KeyAlgorithm -> HashAlgorithm -> [SignatureSubpacket] -> [SignatureSubpacket] -> Word16 -> MPI -> Packet
 signaturePacket version signature_type key_algorithm hash_algorithm hashed_subpackets unhashed_subpackets hash_head signature =
         let p = SignaturePacket {