Added support for v3 keys which is really just a subset of v4.
Signature packet rfc4880 - 5.2.2
v3 signatures were fairly limited and had a static format, v4 introduced the sub-packets for each different element of data.
Public key packet rfc4880 - 5.5.2
The v3 public key contained the validity period which was moved to the signature packet in v4
Private key packet rfc4880 - 5.5.3
No real difference apart from the public key packet at the start which contains the validity period. Logging of the key encryption method and encrypted key data was also added.
Added support for v3 keys which is really just a subset of v4.
Signature packet rfc4880 - 5.2.2 v3 signatures were fairly limited and had a static format, v4 introduced the sub-packets for each different element of data.
Public key packet rfc4880 - 5.5.2 The v3 public key contained the validity period which was moved to the signature packet in v4
Private key packet rfc4880 - 5.5.3 No real difference apart from the public key packet at the start which contains the validity period. Logging of the key encryption method and encrypted key data was also added.