vim-gnupg/plugin/gnupg.vim
2011-07-06 08:05:32 +02:00

750 lines
23 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" or ".pgp" 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.
"
" Variables:
" g:GPGUseAgent
" If set to 0 a possible available gpg-agent won't be used. Defaults to 1.
"
" Credits:
" Mathieu Clabaut for inspirations through his vimspell.vim script.
" Section: Plugin header {{{1
if (exists("loaded_gnupg") || &cp || exists("#BufReadPre#*.\(gpg\|pgp\)"))
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 *.\(gpg\|pgp\) set viminfo=
" We don't want a swap file, as it writes unencrypted data to disk
autocmd BufNewFile,BufReadPre,FileReadPre *.\(gpg\|pgp\) set noswapfile
" Initialize the internal variables
autocmd BufNewFile,BufReadPre,FileReadPre *.\(gpg\|pgp\) call s:GPGInit()
" Force the user to edit the recipient list if he opens a new file
autocmd BufNewFile *.\(gpg\|pgp\) call s:GPGEditRecipients()
" Switch to binary mode to read the encrypted file
autocmd BufReadPre,FileReadPre *.\(gpg\|pgp\) set bin
autocmd BufReadPost,FileReadPost *.\(gpg\|pgp\) call s:GPGDecrypt()
" Switch to normal mode for editing
autocmd BufReadPost,FileReadPost *.\(gpg\|pgp\) set nobin
" Call the autocommand for the file minus .gpg$
autocmd BufReadPost,FileReadPost *.\(gpg\|pgp\) execute ":doautocmd BufReadPost " . expand("%:r")
autocmd BufReadPost,FileReadPost *.\(gpg\|pgp\) execute ":redraw!"
" Switch to binary mode before encrypt the file
autocmd BufWritePre,FileWritePre *.\(gpg\|pgp\) set bin
" Convert all text to encrypted text before writing
autocmd BufWritePre,FileWritePre *.\(gpg\|pgp\) call s:GPGEncrypt()
" Undo the encryption so we are back in the normal text, directly
" after the file has been written.
autocmd BufWritePost,FileWritePost *.\(gpg\|pgp\) silent u
" Switch back to normal mode for editing
autocmd BufWritePost,FileWritePost *.\(gpg\|pgp\) 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()
" check if gpg-agent is allowed
if (!exists("g:GPGUseAgent"))
let g:GPGUseAgent = 1
endif
" determine if gnupg can use the gpg-agent
if (exists("$GPG_AGENT_INFO") && g:GPGUseAgent == 1)
if (!exists("$GPG_TTY"))
echohl GPGError
echo "The GPG_TTY is not set!"
echo "gpg-agent might not work."
echohl None
endif
let s:GPGCommand="LANG=C gpg --use-agent"
else
let s:GPGCommand="LANG=C gpg --no-use-agent"
endif
" setup shell environment for unix and windows
let s:shellredirsave=&shellredir
let s:shellsave=&shell
if (match(&shell,"cmd.exe"))
" windows specific settings
let s:shellredir = '>%s'
let s:shell = &shell
let s:redirnull = '2>nul'
else
" unix specific settings
let s:shellredir = &shellredir
let s:shell = 'sh'
let s:redirnull ='2>/dev/null'
endi
" find the supported algorithms
let &shellredir=s:shellredir
let &shell=s:shell
let output=system(s:GPGCommand . " --version")
let &shellredir=s:shellredir
let &shell=s:shellsave
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 &shellredir=s:shellredir
let &shell=s:shell
let output=system(s:GPGCommand . " --decrypt --dry-run --batch " . filename)
let &shellredir=s:shellredir
let &shell=s:shellsave
" 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 shell temporarily)
let &shellredir=s:shellredir
let &shell=s:shell
exec "'[,']!" . s:GPGCommand . " --quiet --decrypt " . s:redirnull
let &shellredir=s:shellredir
let &shell=s:shellsave
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 &shellredir=s:shellredir
let &shell=s:shell
silent exec "'[,']!" . s:GPGCommand . " --quiet --no-encrypt-to " . options . recipients . " " . s:redirnull
let &shellredir=s:shellredir
let &shell=s:shellsave
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\\|pgp\\)$") >= 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:.*$", "", "")
" only do this if the line is not empty
if (strlen(recipient) > 0)
let gpgid=s:GPGNameToID(recipient)
if (strlen(gpgid) > 0)
let GPGRecipients=GPGRecipients . gpgid . ":"
else
let GPGUnknownRecipients=GPGUnknownRecipients . recipient . ":"
echohl GPGWarning
echo "The recipient " . recipient . " is not in your public keyring!"
echohl None
end
endi
let currentline=currentline+1
let recipient=getline(currentline)
endw
" write back the new recipient list to the corresponding buffer and mark it
" as modified
call setbufvar(b:corresponding_to, "GPGRecipients", GPGRecipients)
call setbufvar(b:corresponding_to, "GPGUnknownRecipients", GPGUnknownRecipients)
call setbufvar(b:corresponding_to, "&mod", 1)
"echo "GPGRecipients=\"" . getbufvar(b:corresponding_to, "GPGRecipients") . "\""
" check if there is any known recipient
if (strlen(s:GetField(GPGRecipients, ":", 0)) == 0)
echohl GPGError
echo 'There are no known recipients!'
echohl None
endi
endf
" Function: s:GPGViewOptions() {{{2
"
" echo the recipients
"
fun s:GPGViewOptions()
if (exists("b:GPGOptions"))
echo 'This file has following options:'
" echo the options
let field=0
let option=s:GetField(b:GPGOptions, ":", field)
while (strlen(option) > 0)
echo option
let field=field+1
let option=s:GetField(b:GPGOptions, ":", field)
endw
endi
endf
" Function: s:GPGEditOptions() {{{2
"
" create a scratch buffer with all recipients to add/remove recipients
"
fun s:GPGEditOptions()
" only do this if it isn't already a GPGOptions_* buffer
if (match(bufname("%"), "^\\(GPGRecipients_\\|GPGOptions_\\)") != 0 && match(bufname("%"), "\.\\(gpg\\|pgp\\)$") >= 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 &shellredir=s:shellredir
let &shell=s:shell
let output=system(s:GPGCommand . " --quiet --with-colons --fixed-list-mode --list-keys \"" . a:name . "\"")
let &shellredir=s:shellredir
let &shell=s:shellsave
" 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 &shellredir=s:shellredir
let &shell=s:shell
let output=system(s:GPGCommand . " --quiet --with-colons --fixed-list-mode --list-keys " . a:identity )
let &shellredir=s:shellredir
let &shell=s:shellsave
" 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: