Add preferred compression algorithm signature subpacket parsing to PGPPacket

From RFC 4880 [1]:

  (array of one-octet values)

  Compression algorithm numbers that indicate which algorithms the key
  holder prefers to use.  Like the preferred symmetric algorithms, the
  list is ordered.  Algorithm numbers are in Section 9.  If this
  subpacket is not included, ZIP is preferred.  A zero denotes that
  uncompressed data is preferred; the key holder's software might have
  no compression software in that implementation.  This is only found
  on a self-signature.

[1]: http://tools.ietf.org/search/rfc4880#section-5.2.3.9

diff --git a/gpg-migrate.py b/gpg-migrate.py
index 782fa4e63d0a3c344489129108f9d2a3a4fee754..9fa4c026eb42263d07896b76a851c736ec988b6c 100755 (executable)
--- a/gpg-migrate.py
+++ b/gpg-migrate.py
@@ -302,6 +302,11 @@ class PGPPacket (dict):
         return ', '.join(
             algo for algo in subpacket['preferred-hash-algorithms'])
 
+    def _str_preferred_compression_algorithms_signature_subpacket(
+            self, subpacket):
+        return ', '.join(
+            algo for algo in subpacket['preferred-compression-algorithms'])
+
     def _str_key_flags_signature_subpacket(self, subpacket):
         return ', '.join(x for x in sorted(subpacket['key-flags']))
 
@@ -571,6 +576,11 @@ class PGPPacket (dict):
         subpacket['preferred-hash-algorithms'] = [
             self._hash_algorithms[d] for d in data]
 
+    def _parse_preferred_compression_algorithms_signature_subpacket(
+            self, data, subpacket):
+        subpacket['preferred-compression-algorithms'] = [
+            self._compression_algorithms[d] for d in data]
+
     def _parse_key_flags_signature_subpacket(self, data, subpacket):
         subpacket['key-flags'] = set()
         if data[0] & 0x1: