From e6203c891c40c420ce6a3a2149019c4d796f419b Mon Sep 17 00:00:00 2001 From: Peter Palfrader Date: Thu, 18 Sep 2008 22:16:53 +0200 Subject: [PATCH] Start editing and parsing userfile --- pws | 257 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 244 insertions(+), 13 deletions(-) diff --git a/pws b/pws index 85a9ea5..80e2baf 100755 --- a/pws +++ b/pws @@ -2,13 +2,24 @@ require 'optparse' require 'thread' +require 'tempfile' +require 'yaml' Thread.abort_on_exception = true GNUPG = "/usr/bin/gpg" $program_name = File.basename($0, '.*') +$editor = ENV['EDITOR'] +if $editor == nil + %w{/usr/bin/sensible-editor /usr/bin/editor /usr/bin/vi}.each do |editor| + if FileTest.executable?(editor) + $editor = editor + break + end + end +end class GnuPG @@my_keys = nil @@ -87,23 +98,116 @@ class GnuPG end end -class EncryptedFile - attr_reader :accessible, :encrypted, :readable +def read_input(query, default_yes=true) + if default_yes + append = '[Y/n]' + else + append = '[y/N]' + end - def initialize(filename) - unless FileTest.readable?(filename) - @accessible = false - return + while true + print "#{query} #{append} " + i = STDIN.readline.chomp.downcase + if i=="" + return default_yes + elsif i=="y" + return true + elsif i=="n" + return false end - @accessible = true - content = File.read(filename) - (outtxt, stderrtxt, statustxt) = GnuPG.gpgcall(content, %w{--with-colons --no-default-keyring --secret-keyring=/dev/null --keyring=/dev/null}) - @encrypted = !(statustxt =~ /\[GNUPG:\] NODATA/) - if @encrypted - @readers = EncryptedFile.list_readers(statustxt) - @readable = EncryptedFile.determine_readable(@readers) + end +end + +class Config + def initialize + begin + f = File.open('.users') + rescue Exception => e + STDERR.puts e + exit(1) + end + + @users = {} + @groups = {} + + lno = 0 + f.readlines.each do |line| + lno = lno+1 + next if line =~ /^$/ + next if line =~ /^#/ + if (m = /^([a-zA-Z0-9-]+)\s*=\s*([0-9A-Fa-f]{40})\s*$/.match line) + user = m[1] + fpr = m[2] + if @users.has_key?(user) + STDERR.puts "User #{user} redefined at line #{lno}!" + exit(1) + end + @users[user] = fpr + elsif (m = /^(@[a-zA-Z0-9-]+)\s*=\s*(.*)$/.match line) + group = m[1] + members = m[2].strip + if @groups.has_key?(group) + STDERR.puts "Group #{group} redefined at line #{lno}!" + exit(1) + end + members = members.split(/[\t ,]+/) + @groups[group] = { "members" => members } + end + end + + @groups.each_pair do |groupname, group| + group['members'].each do |member| + if (member =~ /^@/) + unless (@groups.has_key?(member)) + STDERR.puts "Group #{groupname} contains unknown member #{member}" + exit(1) + end + else + unless @users.has_key?(member) + STDERR.puts "Group #{groupname} contains unknown member #{member}" + exit(1) + end + end + end + group['members_to_do'] = group['members'].clone + end + + while true + had_progress = false + all_expanded = true + @groups.each_pair do |groupname, group| + group['keys'] = [] unless group['keys'] + + still_contains_groups = false + group['members_to_do'].each do |member| + if (member =~ /^@/) + if @groups[member]['members_to_do'].size == 0 + group['keys'].concat @groups[member]['keys'] + group['members_to_do'].delete(member) + had_progress = true + else + still_contains_groups = true + end + else + group['keys'].push @users[member] + group['members_to_do'].delete(member) + had_progress = true + end + end + all_expanded = false if still_contains_groups + end + break if all_expanded + unless had_progress + cyclic_groups = @groups.keys.reject{|name| @groups[name]['members_to_do'].size == 0}.join(", ") + STDERR.puts "Cyclic group memberships in #{cyclic_groups}?" + exit(1) + end end end +end + +class EncryptedFile + attr_reader :accessible, :encrypted, :readable def EncryptedFile.determine_readable(readers) GnuPG.get_my_keys.each do |keyid| @@ -121,6 +225,55 @@ class EncryptedFile end return readers end + + def EncryptedFile.targets(text) + metaline = text.split("\n").first + m = /^access: (.*)/.match metaline + return [] unless m + return m[1].strip.split(/\s+/) + end + + + def initialize(filename) + @filename = filename + unless FileTest.readable?(filename) + @accessible = false + return + end + @accessible = true + @encrypted_content = File.read(filename) + (outtxt, stderrtxt, statustxt) = GnuPG.gpgcall(@encrypted_content, %w{--with-colons --no-default-keyring --secret-keyring=/dev/null --keyring=/dev/null}) + @encrypted = !(statustxt =~ /\[GNUPG:\] NODATA/) + if @encrypted + @readers = EncryptedFile.list_readers(statustxt) + @readable = EncryptedFile.determine_readable(@readers) + end + end + + def decrypt + (outtxt, stderrtxt, statustxt, exitstatus) = GnuPG.gpgcall(@encrypted_content, %w{--decrypt}) + if exitstatus != 0 + proceed = read_input("Warning: gpg returned non-zero exit status #{exitstatus} when decrypting #{@filename}. Proceed?") + exit(0) unless proceed + elsif outtxt.length == 0 + proceed = read_input("Warning: #{@filename} decrypted to an empty file. Proceed?") + exit(0) unless proceed + end + + return outtxt + end + + def write_back(content) + targets = EncryptedFile.targets(content) + if targets.size == 0 + tryagain = read_input("Warning: Did not find targets to encrypt to in header. Try again (or exit)?", true) + return false if tryagain + exit(0) + end + + Config.new + #expanded = GnuPG.expand_targets(targets) + end end class Ls @@ -181,8 +334,86 @@ class Ls end end +class Ed + def help(parser, code=0, io=STDOUT) + io.puts "Usage: #{$program_name} ed " + io.puts parser.summarize + io.puts "Decrypts the file, spawns an editor, and encrypts it again" + exit(code) + end + + def edit(filename) + f = EncryptedFile.new(filename) + if !f.readable && !@force + STDERR.puts "#{filename} is probably not readable" + exit(1) + end + + content = f.decrypt + while true + oldsize = content.length + tempfile = Tempfile.open('pws') + tempfile.puts content + tempfile.flush + system($editor, tempfile.path) + status = $? + throw "Process has not exited!?" unless status.exited? + unless status.exitstatus == 0 + proceed = read_input("Warning: Editor did not exit successfully (exit code #{status.exitstatus}. Proceed?") + exit(0) unless proceed + end + tempfile.seek(0, IO::SEEK_SET) + content = tempfile.read + + # zero the file + newsize = content.length + tempfile.seek(0, IO::SEEK_SET) + clearsize = (newsize > oldsize) ? newsize : oldsize + tempfile.print "\0"*clearsize + tempfile.fsync + tempfile.close(true) + + if content.length == 0 + proceed = read_input("Warning: Content is now empty. Proceed?") + exit(0) unless proceed + end + + success = f.write_back(content) + break if success + end + end + + def initialize() + ARGV.options do |opts| + opts.on_tail("-h", "--help" , "Display this help screen") { help(opts) } + opts.on_tail("-f", "--force" , "Spawn an editor even if the file is probably not readable") { |@force| } + opts.parse! + end + help(ARGV.options, 1, STDERR) if ARGV.length != 1 + filename = ARGV.shift + + if !FileTest.exists?(filename) + STDERR.puts "#{filename} does not exist" + exit(1) + elsif !FileTest.file?(filename) + STDERR.puts "#{filename} is not a regular file" + exit(1) + elsif !FileTest.readable?(filename) + STDERR.puts "#{filename} is not accessible (unix perms)" + exit(1) + end + + dirname = File.dirname(filename) + basename = File.basename(filename) + Dir.chdir(dirname) { + edit(basename) + } + end +end + case ARGV.shift when 'ls': Ls.new + when 'ed': Ed.new else STDERR.puts "What!?" end -- 2.39.5