GPG and Vim
October 22, 2007 at 12:10 PM by Dr. Drang
In my previous post, I mentioned that I used to use Vim to automatically encrypt and decrypt my file of user names and passwords. A reader emailed to ask for the configuration file that allowed this transparent behavior, so here it is. It’s called gpg.vim and is kept in the ~/.vim/plugin directory.
" Transparent editing of gpg encrypted files.
" By Wouter Hanegraaff <wouter@blub.net>
augroup encrypted
au!
" First make sure nothing is written to ~/.viminfo while editing
" an encrypted file.
autocmd BufReadPre,FileReadPre *.asc set viminfo=
" We don't want a swap file, as it writes unencrypted data to disk
autocmd BufReadPre,FileReadPre *.asc set noswapfile
" Switch to binary mode to read the encrypted file
autocmd BufReadPre,FileReadPre *.asc set bin
autocmd BufReadPre,FileReadPre *.asc let ch_save = &ch|set ch=2
autocmd BufReadPost,FileReadPost *.asc '[,']!gpg -qd 2> /dev/null
" Switch to normal mode for editing
autocmd BufReadPost,FileReadPost *.asc set nobin
autocmd BufReadPost,FileReadPost *.asc let &ch = ch_save|unlet ch_save
autocmd BufReadPost,FileReadPost *.asc execute ":doautocmd BufReadPost " . expand("%:r")
autocmd BufReadPost,FileReadPost *.asc set ff=unix
" Convert all text to encrypted text before writing
autocmd BufWritePre,FileWritePre *.asc '[,']!gpg --default-recipient-self -ae 2>/dev/null
" Undo the encryption so we are back in the normal text, directly
" after the file has been written.
autocmd BufWritePost,FileWritePost *.asc u
" First make sure nothing is written to ~/.viminfo while editing
" an encrypted file.
autocmd BufReadPre,FileReadPre *.gpg set viminfo=
" We don't want a swap file, as it writes unencrypted data to disk
autocmd BufReadPre,FileReadPre *.gpg set noswapfile
" Switch to binary mode to read the encrypted file
autocmd BufReadPre,FileReadPre *.gpg set bin
autocmd BufReadPre,FileReadPre *.gpg let ch_save = &ch|set ch=2
autocmd BufReadPost,FileReadPost *.gpg '[,']!gpg -qd 2> /dev/null
" Switch to normal mode for editing
autocmd BufReadPost,FileReadPost *.gpg set nobin
autocmd BufReadPost,FileReadPost *.gpg let &ch = ch_save|unlet ch_save
autocmd BufReadPost,FileReadPost *.gpg execute ":doautocmd BufReadPost " . expand("%:r")
autocmd BufReadPost,FileReadPost *.gpg set ff=unix
" Convert all text to encrypted text before writing
autocmd BufWritePre,FileWritePre *.gpg '[,']!gpg --default-recipient-self -e 2>/dev/null
" Undo the encryption so we are back in the normal text, directly
" after the file has been written.
autocmd BufWritePost,FileWritePost *.gpg u
augroup END
As you can tell from the top line, this file is not original with me but was downloaded from somewhere lost in the mists of memory and modified. Googling “Wouter Hanegraaff gpg” will get you a shorter version that handles only binary encrypted files, not ASCII-armored files. I guess the lines that work with *.asc files are mine, although I can’t take much credit for them—they are nothing more than an obvious rewrite of the lines that handle *.gpg files.
If you are a Vim user, you may want to look into another GPG configuration file, written by Markus Braun. You can find it here (thanks to Karsten Hokamp for the tip).
