vim-gnupg/plugin/gnupg.vim
Markus Braun 167ef9a4f3 GnuPG plugin for Vim
This script implements transparent editing of gpg encrypted files. The
filename must have a ".gpg" suffix. When opening such a file the content
is decrypted, when opening a new file the script will ask for the
recipients of the encrypted file. The file content will be encrypted to
all recipients before it is written. The script turns off viminfo and
swapfile to increase security.
2011-07-06 08:04:37 +02:00

714 lines
22 KiB
VimL

" Name: gnupg.vim
" Version: $Id$
" Author: Markus Braun <markus.braun@krawel.de>
" Summary: Vim plugin for transparent editing of gpg encrypted files.
" Licence: This program is free software; you can redistribute it and/or
" modify it under the terms of the GNU General Public License.
" See http://www.gnu.org/copyleft/gpl.txt
" Section: Documentation {{{1
" Description:
"
" This script implements transparent editing of gpg encrypted files. The
" filename must have a ".gpg" suffix. When opening such a file the content
" is decrypted, when opening a new file the script will ask for the
" recipients of the encrypted file. The file content will be encrypted to
" all recipients before it is written. The script turns off viminfo and
" swapfile to increase security.
"
" Installation:
"
" Copy the gnupg.vim file to the $HOME/.vim/plugin directory.
" Refer to ':help add-plugin', ':help add-global-plugin' and ':help
" runtimepath' for more details about Vim plugins.
"
" Commands:
"
" :GPGEditRecipients
" Opens a scratch buffer to change the list of recipients. Recipients that
" are unknown (not in your public key) are highlighted and have a
" prepended "!". Closing the buffer with :x or :bd makes the changes
" permanent.
"
" :GPGViewRecipients
" Prints the list of recipients.
"
" :GPGEditOptions
" Opens a scratch buffer to change the options for encryption (symmetric,
" asymmetric, signing). Closing the buffer with :x or :bd makes the
" changes permanent.
" WARNING: There is no check of the entered options, so you need to know
" what you are doing.
"
" :GPGViewRecipients
" Prints the list of options.
"
" Credits:
" Mathieu Clabaut for inspirations through his vimspell.vim script.
" Section: Plugin header {{{1
if (exists("loaded_gnupg") || &cp || exists("#BufReadPre#*.gpg"))
finish
endi
let loaded_gnupg = 1
" Section: Autocmd setup {{{1
augroup GnuPG
au!
" First make sure nothing is written to ~/.viminfo while editing
" an encrypted file.
autocmd BufNewFile,BufReadPre,FileReadPre *.gpg set viminfo=
" We don't want a swap file, as it writes unencrypted data to disk
autocmd BufNewFile,BufReadPre,FileReadPre *.gpg set noswapfile
" Initialize the internal variables
autocmd BufNewFile,BufReadPre,FileReadPre *.gpg call s:GPGInit()
" Force the user to edit the recipient list if he opens a new file
autocmd BufNewFile *.gpg call s:GPGEditRecipients()
" Switch to binary mode to read the encrypted file
autocmd BufReadPre,FileReadPre *.gpg set bin
autocmd BufReadPost,FileReadPost *.gpg call s:GPGDecrypt()
" Switch to normal mode for editing
autocmd BufReadPost,FileReadPost *.gpg set nobin
" Call the autocommand for the file minus .gpg$
autocmd BufReadPost,FileReadPost *.gpg execute ":doautocmd BufReadPost " . expand("%:r")
autocmd BufReadPost,FileReadPost *.gpg execute ":redraw!"
" Switch to binary mode before encrypt the file
autocmd BufWritePre,FileWritePre *.gpg set bin
" Convert all text to encrypted text before writing
autocmd BufWritePre,FileWritePre *.gpg call s:GPGEncrypt()
" Undo the encryption so we are back in the normal text, directly
" after the file has been written.
autocmd BufWritePost,FileWritePost *.gpg silent u
" Switch back to normal mode for editing
autocmd BufWritePost,FileWritePost *.gpg set nobin
augroup END
" Section: Highlight setup {{{1
highlight default GPGWarning term=reverse ctermfg=Yellow guifg=Yellow
highlight default GPGError term=reverse ctermfg=Red guifg=Red
highlight default GPGHighlightUnknownRecipient term=reverse ctermfg=Red cterm=underline guifg=Red gui=underline
" Section: Functions {{{1
" Function: s:GPGInit() {{{2
"
" initialize the plugin
"
fun s:GPGInit()
" determine if gnupg can use the gpg-agent
if (exists("$GPG_AGENT_INFO"))
let s:gpgcommand="LANG=C gpg --use-agent"
else
let s:gpgcommand="LANG=C gpg --no-use-agent"
endif
" find the supported algorithms
let shsave=&sh
let &sh='sh'
let output=system(s:gpgcommand . " --version")
let &sh=shsave
let s:GPGPubkey=substitute(output, ".*Pubkey: \\(.\\{-}\\)\n.*", "\\1", "")
let s:GPGCipher=substitute(output, ".*Cipher: \\(.\\{-}\\)\n.*", "\\1", "")
let s:GPGHash=substitute(output, ".*Hash: \\(.\\{-}\\)\n.*", "\\1", "")
let s:GPGCompress=substitute(output, ".*Compress: \\(.\\{-}\\)\n.*", "\\1", "")
endf
" Function: s:GPGDecrypt() {{{2
"
" decrypt the buffer and find all recipients of the encrypted file
"
fun s:GPGDecrypt()
" get the filename of the current buffer
let filename=escape(expand("%:p"), ' *?\"'."'")
" clear GPGRecipients, GPGUnknownRecipients and GPGOptions
let b:GPGRecipients=""
let b:GPGUnknownRecipients=""
let b:GPGOptions=""
" find the recipients of the file
let shsave=&sh
let &sh='sh'
let output=system(s:gpgcommand . " --decrypt --dry-run --batch " . filename)
let &sh=shsave
" check if the file is symmetric/asymmetric encrypted
if (match(output, "gpg: [^ ]\\+ encrypted data") >= 0)
" file is symmetric encrypted
let b:GPGOptions=b:GPGOptions . "symmetric:"
let cipher=substitute(output, ".*gpg: \\([^ ]\\+\\) encrypted data.*", "\\1", "")
if (match(s:GPGCipher, "\\<" . cipher . "\\>") >= 0)
let b:GPGOptions=b:GPGOptions . "cipher-algo " . cipher . ":"
else
echohl GPGWarning
echo "The cipher " . cipher . " is not known by the local gpg command. Using default!"
echo
echohl None
endi
else
" file is asymmetric encrypted
let b:GPGOptions=b:GPGOptions . "encrypt:"
let start=match(output, "ID [[:xdigit:]]\\{8}")
while (start >= 0)
let start=start+3
let recipient=strpart(output, start, 8)
let name=s:GPGNameToID(recipient)
if (strlen(name) > 0)
let b:GPGRecipients=b:GPGRecipients . name . ":"
else
let b:GPGUnknownRecipients=b:GPGUnknownRecipients . recipient . ":"
echohl GPGWarning
echo "The recipient " . recipient . " is not in your public keyring!"
echohl None
end
let start=match(output, "ID [[:xdigit:]]\\{8}", start)
endw
"echo "GPGRecipients=\"" . b:GPGRecipients . "\""
endi
" check if the message is armored
if (stridx(getline(1), "-----BEGIN PGP MESSAGE-----") >= 0)
let b:GPGOptions=b:GPGOptions . "armor:"
endi
" finally decrypt the buffer content
" since even with the --quiet option passphrase typos will be reported,
" we must redirect stderr (using sh temporarily)
let shsave=&sh
let &sh='sh'
exec "'[,']!" . s:gpgcommand . " --quiet --decrypt 2>/dev/null"
let &sh=shsave
if (v:shell_error) " message could not be decrypted
silent u
echohl GPGError
let asd=input("Message could not be decrypted! (Press ENTER)")
echohl None
bwipeout
return
endi
endf
" Function: s:GPGEncrypt() {{{2
"
" encrypts the buffer to all previous recipients
"
fun s:GPGEncrypt()
let options=""
let recipients=""
let field=0
" built list of options
if (!exists("b:GPGOptions") || strlen(b:GPGOptions) == 0)
let b:GPGOptions="encrypt:"
endi
let field=0
let option=s:GetField(b:GPGOptions, ":", field)
while (strlen(option))
let options=options . " --" . option . " "
let field=field+1
let option=s:GetField(b:GPGOptions, ":", field)
endw
" check if there are unknown recipients and warn
if (exists("b:GPGUnknownRecipients") && strlen(b:GPGUnknownRecipients) > 0)
echohl GPGWarning
echo "There are unknown recipients!!"
echo "Please use GPGEditRecipients to correct!!"
echo
echohl None
endi
" built list of recipients
if (exists("b:GPGRecipients") && strlen(b:GPGRecipients) > 0)
let field=0
let gpgid=s:GetField(b:GPGRecipients, ":", field)
while (strlen(gpgid))
let recipients=recipients . " -r " . gpgid
let field=field+1
let gpgid=s:GetField(b:GPGRecipients, ":", field)
endw
else
if (match(b:GPGOptions, "symmetric:") < 0)
echohl GPGError
echo "There are no recipients!!"
echo "Please use GPGEditRecipients to correct!!"
echo
echohl None
endi
endi
" encrypt the buffer
let shsave=&sh
let &sh='sh'
silent exec "'[,']!" . s:gpgcommand . " --quiet --no-encrypt-to " . options . recipients . " 2>/dev/null"
let &sh=shsave
if (v:shell_error) " message could not be encrypted
silent u
echohl GPGError
let asd=input("Message could not be encrypted! File might be empty! (Press ENTER)")
echohl None
bwipeout
return
endi
"redraw!
endf
" Function: s:GPGViewRecipients() {{{2
"
" echo the recipients
"
fun s:GPGViewRecipients()
if (exists("b:GPGRecipients"))
echo 'This file has following recipients (Unknown recipients have a prepended "!"):'
" echo the recipients
let field=0
let name=s:GetField(b:GPGRecipients, ":", field)
while (strlen(name) > 0)
let name=s:GPGIDToName(name)
echo name
let field=field+1
let name=s:GetField(b:GPGRecipients, ":", field)
endw
" put the unknown recipients in the scratch buffer
let field=0
echohl GPGWarning
let name=s:GetField(b:GPGUnknownRecipients, ":", field)
while (strlen(name) > 0)
let name="!" . name
echo name
let field=field+1
let name=s:GetField(b:GPGUnknownRecipients, ":", field)
endw
echohl None
" check if there is any known recipient
if (strlen(s:GetField(b:GPGRecipients, ":", 0)) == 0)
echohl GPGError
echo 'There are no known recipients!'
echohl None
endi
endi
endf
" Function: s:GPGEditRecipients() {{{2
"
" create a scratch buffer with all recipients to add/remove recipients
"
fun s:GPGEditRecipients()
" only do this if it isn't already a GPGRecipients_* buffer
if (match(bufname("%"), "^\\(GPGRecipients_\\|GPGOptions_\\)") != 0 && match(bufname("%"), "\.gpg$") >= 0)
" save buffer name
let buffername=bufname("%")
let editbuffername="GPGRecipients_" . buffername
" create scratch buffer
exe 'silent! split ' . editbuffername
" check if this buffer exists
if (bufexists(editbuffername))
" empty the buffer
silent normal! 1GdG
endi
" Mark the buffer as a scratch buffer
setlocal buftype=nofile
setlocal noswapfile
setlocal nowrap
setlocal nobuflisted
setlocal nonumber
" so we know for which other buffer this edit buffer is
let b:corresponding_to=buffername
" put some comments to the scratch buffer
silent put ='GPG: ----------------------------------------------------------------------'
silent put ='GPG: Please edit the list of recipients, one recipient per line'
silent put ='GPG: Unknown recipients have a prepended \"!\"'
silent put ='GPG: Lines beginning with \"GPG:\" are removed automatically'
silent put ='GPG: Use :x or :bd to close this buffer'
silent put ='GPG: ----------------------------------------------------------------------'
" put the recipients in the scratch buffer
let recipients=getbufvar(b:corresponding_to, "GPGRecipients")
let field=0
let name=s:GetField(recipients, ":", field)
while (strlen(name) > 0)
let name=s:GPGIDToName(name)
silent put =name
let field=field+1
let name=s:GetField(recipients, ":", field)
endw
" put the unknown recipients in the scratch buffer
let unknownRecipients=getbufvar(b:corresponding_to, "GPGUnknownRecipients")
let field=0
let syntaxPattern="\\(nonexistingwordinthisbuffer"
let name=s:GetField(unknownRecipients, ":", field)
while (strlen(name) > 0)
let name="!" . name
let syntaxPattern=syntaxPattern . "\\|" . name
silent put =name
let field=field+1
let name=s:GetField(unknownRecipients, ":", field)
endw
let syntaxPattern=syntaxPattern . "\\)"
" define highlight
if (has("syntax") && exists("g:syntax_on"))
exec('syntax match GPGUnknownRecipient "' . syntaxPattern . '"')
highlight clear GPGUnknownRecipient
highlight link GPGUnknownRecipient GPGHighlightUnknownRecipient
syntax match GPGComment "^GPG:.*$"
highlight clear GPGComment
highlight link GPGComment Comment
endi
" delete the empty first line
silent normal! 1Gdd
" jump to the first recipient
silent normal! 6G
" add a autocommand to regenerate the recipients after a write
augroup GPGEditRecipients
augroup END
execute 'au GPGEditRecipients BufHidden ' . editbuffername . ' call s:GPGFinishRecipientsBuffer()'
endi
endf
" Function: s:GPGFinishRecipientsBuffer() {{{2
"
" create a new recipient list from RecipientsBuffer
fun s:GPGFinishRecipientsBuffer()
" clear GPGRecipients and GPGUnknownRecipients
let GPGRecipients=""
let GPGUnknownRecipients=""
" delete the autocommand
exe "au! GPGEditRecipients * " . bufname("%")
let currentline=1
let recipient=getline(currentline)
" get the recipients from the scratch buffer
while (currentline <= line("$"))
" delete all spaces at beginning and end of the line
" also delete a '!' at the beginning of the line
let recipient=substitute(recipient, "^[[:space:]!]*\\(.\\{-}\\)[[:space:]]*$", "\\1", "")
" delete comment lines
let recipient=substitute(recipient, "^GPG:.*$", "", "")
" only do this if the line is not empty
if (strlen(recipient) > 0)
let gpgid=s:GPGNameToID(recipient)
if (strlen(gpgid) > 0)
let GPGRecipients=GPGRecipients . gpgid . ":"
else
let GPGUnknownRecipients=GPGUnknownRecipients . recipient . ":"
echohl GPGWarning
echo "The recipient " . recipient . " is not in your public keyring!"
echohl None
end
endi
let currentline=currentline+1
let recipient=getline(currentline)
endw
" write back the new recipient list to the corresponding buffer and mark it
" as modified
call setbufvar(b:corresponding_to, "GPGRecipients", GPGRecipients)
call setbufvar(b:corresponding_to, "GPGUnknownRecipients", GPGUnknownRecipients)
call setbufvar(b:corresponding_to, "&mod", 1)
"echo "GPGRecipients=\"" . getbufvar(b:corresponding_to, "GPGRecipients") . "\""
" check if there is any known recipient
if (strlen(s:GetField(GPGRecipients, ":", 0)) == 0)
echohl GPGError
echo 'There are no known recipients!'
echohl None
endi
endf
" Function: s:GPGViewOptions() {{{2
"
" echo the recipients
"
fun s:GPGViewOptions()
if (exists("b:GPGOptions"))
echo 'This file has following options:'
" echo the options
let field=0
let option=s:GetField(b:GPGOptions, ":", field)
while (strlen(option) > 0)
echo option
let field=field+1
let option=s:GetField(b:GPGOptions, ":", field)
endw
endi
endf
" Function: s:GPGEditOptions() {{{2
"
" create a scratch buffer with all recipients to add/remove recipients
"
fun s:GPGEditOptions()
" only do this if it isn't already a GPGOptions_* buffer
if (match(bufname("%"), "^\\(GPGRecipients_\\|GPGOptions_\\)") != 0 && match(bufname("%"), "\.gpg$") >= 0)
" save buffer name
let buffername=bufname("%")
let editbuffername="GPGOptions_" . buffername
" create scratch buffer
exe 'silent! split ' . editbuffername
" check if this buffer exists
if (bufexists(editbuffername))
" empty the buffer
silent normal! 1GdG
endi
" Mark the buffer as a scratch buffer
setlocal buftype=nofile
setlocal noswapfile
setlocal nowrap
setlocal nobuflisted
setlocal nonumber
" so we know for which other buffer this edit buffer is
let b:corresponding_to=buffername
" put some comments to the scratch buffer
silent put ='GPG: ----------------------------------------------------------------------'
silent put ='GPG: THERE IS NO CHECK OF THE ENTERED OPTIONS!'
silent put ='GPG: YOU NEED TO KNOW WHAT YOU ARE DOING!'
silent put ='GPG: IF IN DOUBT, QUICKLY EXIT USING :x OR :bd'
silent put ='GPG: Please edit the list of options, one option per line'
silent put ='GPG: Please refer to the gpg documentation for valid options'
silent put ='GPG: Lines beginning with \"GPG:\" are removed automatically'
silent put ='GPG: Use :x or :bd to close this buffer'
silent put ='GPG: ----------------------------------------------------------------------'
" put the options in the scratch buffer
let options=getbufvar(b:corresponding_to, "GPGOptions")
let field=0
let option=s:GetField(options, ":", field)
while (strlen(option) > 0)
silent put =option
let field=field+1
let option=s:GetField(options, ":", field)
endw
" delete the empty first line
silent normal! 1Gdd
" jump to the first option
silent normal! 6G
" add a autocommand to regenerate the options after a write
augroup GPGEditOptions
augroup END
execute 'au GPGEditOptions BufHidden ' . editbuffername . ' call s:GPGFinishOptionsBuffer()'
" define highlight
if (has("syntax") && exists("g:syntax_on"))
syntax match GPGComment "^GPG:.*$"
highlight clear GPGComment
highlight link GPGComment Comment
endi
endi
endf
" Function: s:GPGFinishOptionsBuffer() {{{2
"
" create a new option list from OptionsBuffer
fun s:GPGFinishOptionsBuffer()
" clear GPGOptions and GPGUnknownOptions
let GPGOptions=""
let GPGUnknownOptions=""
" delete the autocommand
exe "au! GPGEditOptions * " . bufname("%")
let currentline=1
let option=getline(currentline)
" get the options from the scratch buffer
while (currentline <= line("$"))
" delete all spaces at beginning and end of the line
" also delete a '!' at the beginning of the line
let option=substitute(option, "^[[:space:]!]*\\(.\\{-}\\)[[:space:]]*$", "\\1", "")
" delete comment lines
let option=substitute(option, "^GPG:.*$", "", "")
" only do this if the line is not empty
if (strlen(option) > 0)
let GPGOptions=GPGOptions . option . ":"
endi
let currentline=currentline+1
let option=getline(currentline)
endw
" write back the new option list to the corresponding buffer and mark it
" as modified
call setbufvar(b:corresponding_to, "GPGOptions", GPGOptions)
call setbufvar(b:corresponding_to, "&mod", 1)
"echo "GPGOptions=\"" . getbufvar(b:corresponding_to, "GPGOptions") . "\""
endf
" Function: s:GPGNameToID(name) {{{2
"
" find GPG key ID corresponding to a name
" Returns: ID for the given name
fun s:GPGNameToID(name)
" ask gpg for the id for a name
let shsave=&sh
let &sh='sh'
let output=system(s:gpgcommand . " --quiet --with-colons --fixed-list-mode --list-keys \"" . a:name . "\"")
let &sh=shsave
" parse the output of gpg
let pub_seen=0
let uid_seen=0
let line=0
let counter=0
let gpgids=""
let choices="The name \"" . a:name . "\" is ambiguous. Please select the correct key:\n"
let linecontent=s:GetField(output, "\n", line)
while (strlen(linecontent))
" search for the next uid
if (pub_seen == 1)
if (s:GetField(linecontent, ":", 0) == "uid")
if (uid_seen == 0)
let choices=choices . counter . ": " . s:GetField(linecontent, ":", 9) . "\n"
let counter=counter+1
let uid_seen=1
else
let choices=choices . " " . s:GetField(linecontent, ":", 9) . "\n"
endi
else
let uid_seen=0
let pub_seen=0
endi
endi
" search for the next pub
if (pub_seen == 0)
if (s:GetField(linecontent, ":", 0) == "pub")
let gpgids=gpgids . s:GetField(linecontent, ":", 4) . ":"
let pub_seen=1
endi
endi
let line=line+1
let linecontent=s:GetField(output, "\n", line)
endw
" counter > 1 means we have more than one results
let answer=0
if (counter > 1)
let choices=choices . "Enter number: "
let answer=input(choices, "0")
while (answer == "")
let answer=input("Enter number: ", "0")
endw
endi
return s:GetField(gpgids, ":", answer)
endf
" Function: s:GPGIDToName(identity) {{{2
"
" find name corresponding to a GPG key ID
" Returns: Name for the given ID
fun s:GPGIDToName(identity)
" TODO is the encryption subkey really unique?
" ask gpg for the id for a name
let shsave=&sh
let &sh='sh'
let output=system(s:gpgcommand . " --quiet --with-colons --fixed-list-mode --list-keys " . a:identity )
let &sh=shsave
" parse the output of gpg
let pub_seen=0
let finish=0
let line=0
let linecontent=s:GetField(output, "\n", line)
while (strlen(linecontent) && !finish)
if (pub_seen == 0) " search for the next pub
if (s:GetField(linecontent, ":", 0) == "pub")
let pub_seen=1
endi
else " search for the next uid
if (s:GetField(linecontent, ":", 0) == "uid")
let pub_seen=0
let finish=1
let uid=s:GetField(linecontent, ":", 9)
endi
endi
let line=line+1
let linecontent=s:GetField(output, "\n", line)
endw
return uid
endf
" Function: s:GetField(line, separator, field) {{{2
"
" find field of 'separator' separated string, counting starts with 0
" Returns: content of the field, if field doesn't exist it returns an empty
" string
fun s:GetField(line, separator, field)
let counter=a:field
let separatorLength=strlen(a:separator)
let start=0
let end=match(a:line, a:separator)
if (end < 0)
let end=strlen(a:line)
endi
" search for requested field
while (start < strlen(a:line) && counter > 0)
let counter=counter-separatorLength
let start=end+separatorLength
let end=match(a:line, a:separator, start)
if (end < 0)
let end=strlen(a:line)
endi
endw
if (start < strlen(a:line))
return strpart(a:line, start, end-start)
else
return ""
endi
endf
" Section: Command definitions {{{1
com! GPGViewRecipients call s:GPGViewRecipients()
com! GPGEditRecipients call s:GPGEditRecipients()
com! GPGViewOptions call s:GPGViewOptions()
com! GPGEditOptions call s:GPGEditOptions()
" vim600: set foldmethod=marker: