The problem#
There's a handy Vim plugin openssl.vim that
allows you to easily edit encrypted files with Vim simply by giving the
file an extension like .aes. Then Vim will ask for a password upon
loading and saving the file in order to decrypt and encrypt it with
openssl.
Unfortunately, the plugin was last updated in 2008 and makes some
assumptions about openssl's defaults which are no longer valid.
The most pressing issue is that the plugin now outputs a warning message
when encrypting. By itself, that's worrisome, but, worse, that warning
message gets output into the file along with the ciphertext. Needless to
say, the resulting file cannot be decrypted without manually removing
the warning text.
The solution#
Simply fixing the options the script passes to openssl is a good
start, but I also wanted to make sure any files encrypted with the old
settings could be decrypted.
My updated openssl.vim1 does both in
addition to fixing some other annoyances.