stand

   1 #!/usr/bin/ruby
   2 #
   3 # Copyright Mark Longair (c) 2002, 2005, 2008 Reuben Thomas (c) 2005-2007.
   4 #
   5 #    This program is free software: you can redistribute it and/or modify
   6 #    it under the terms of the GNU General Public License as published by
   7 #    the Free Software Foundation, either version 3 of the License, or
   8 #    (at your option) any later version.
   9 #
  10 #    This program is distributed in the hope that it will be useful,
  11 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 #    GNU General Public License for more details.
  14 #
  15 #    You should have received a copy of the GNU General Public License
  16 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 #
  18 # This is a simple script for fetching mail from POP3 accounts.
  19 # On a Debian system, you'll need the following packages:
  20 #
  21 #   ruby
  22 #   libruby
  23 #   libopenssl-ruby
  24 #   libsqlite3-ruby
  25 #
  26 # See http://mythic-beasts.com/~mark/software/stand/
  27 # for further remarks.
  28
  29 $program_name = 'stand'
  30
  31 require 'getoptlong'
  32 require 'yaml'
  33 require 'socket'
  34 require 'net/pop'
  35 require 'openssl'
  36 require 'timeout'
  37 require 'sqlite3'
  38
  39 # ----------------------------------------------------------------------
  40 #
  41 # Command line argument parsing...
  42
  43 # Some default values...
  44
  45 $configuration_file = "#{ENV['HOME']}/.stand.yaml"
  46 $configuration_file_pretty = "~/.stand.yaml"
  47 $uidl_database_filename = "#{ENV['HOME']}/.stand-uidls"
  48
  49 def usage
  50
  51   print <<EOF
  52 Usage: #{$program_name} [OPTION]...
  53
  54   -h, --help           Display this message and exit.
  55   -d, --delete         Delete messages on server after fetching.
  56   -n, --no-ssl-verify  Don\'t verify the peer\'s certificate when using SSL.
  57   -f <FILENAME>, --configuration-file=<FILENAME>
  58                        Specify the configuration file to use.
  59                        (default: #{$configuration_file_pretty})
  60   -r <SECONDS>, --reconnect-after=<SECONDS>
  61                        Reconnect to the server if <SECONDS> seconds has
  62                        elapsed since the last connection.
  63 EOF
  64
  65 end
  66
  67 options = GetoptLong.new(
  68   [ "--help", "-h", GetoptLong::NO_ARGUMENT ],
  69   [ "--delete", "-d", GetoptLong::NO_ARGUMENT ],
  70   [ "--no-ssl-verify", "-n", GetoptLong::NO_ARGUMENT ],
  71   [ "--configuration-file", "-f", GetoptLong::REQUIRED_ARGUMENT ],
  72   [ "--reconnect-after", "-r",  GetoptLong::REQUIRED_ARGUMENT ]
  73 )
  74
  75 $keep = true
  76 $ssl_verify = true
  77 $reconnect_after = nil
  78
  79 begin
  80
  81   options.each do |opt, arg|
  82
  83     case opt
  84     when "--help"
  85       usage
  86       exit
  87     when "--delete"
  88       $keep = false
  89     when "--no-ssl-verify"
  90       $ssl_verify = false
  91     when "--configuration-file"
  92       $configuration_file = arg
  93     when "--reconnect-after"
  94       $reconnect_after = Float(arg)
  95     end
  96
  97   end
  98
  99 rescue
 100
 101   STDERR.print "Bad command line option: #{$!}\n"
 102   usage
 103   exit
 104
 105 end
 106
 107 if $keep and $reconnect_after
 108   STDERR.puts "There should be no reason to specify --reconnect-after with --keep"
 109   exit
 110 end
 111
 112 # ----------------------------------------------------------------------
 113
 114 # A fairly idiotic progress class.
 115
 116 class Progress
 117
 118   def initialize(maximum)
 119     @maximum = maximum
 120     @current_value = 0
 121   end
 122
 123   def increase_by(i)
 124     set @current_value + i
 125   end
 126
 127   def set(v)
 128     block_change = (v / 1024) - (@current_value / 1024)
 129     if block_change >= 0
 130       (1..block_change).each { print "." }
 131       $stdout.flush
 132     else
 133       backspaces = - block_change
 134       (1..backspaces).each { print "\b" }
 135       $stdout.flush
 136     end
 137     @current_value = v
 138   end
 139
 140 end
 141
 142 # ----------------------------------------------------------------------
 143
 144 # This class deals with connecting to a POP3 server, and fetching the
 145 # mail from it.
 146
 147 class POP3Account
 148
 149   attr_accessor :host, :user, :port
 150
 151   attr_reader :command
 152
 153   def initialize(host, user, password, use_ssl, use_apop, port, command)
 154     @host = host
 155     @user = user
 156     @password = password
 157     @use_ssl = use_ssl
 158     @use_apop = use_apop
 159     @port = port
 160     @command = command
 161   end
 162
 163   def to_s
 164     "#{@user} at #{@host}:#{@port}#{ @use_ssl ? ' (SSL)' : ''}"
 165   end
 166
 167   def account_uidl(uidl)
 168     "#{@user}@#{@host}:#{@port}##{uidl}"
 169   end
 170
 171   # These three methods manipulate the UIDL database.
 172
 173   def add_uidl_to_db(db,u)
 174     db.execute( "INSERT INTO uidls VALUES (?)", account_uidl(u) )
 175   end
 176
 177   def delete_uidls_from_db(db,a)
 178     a.each do |u|
 179       db.execute( "DELETE FROM uidls WHERE uidl = ?", account_uidl(u) )
 180     end
 181   end
 182
 183   def db_has_uidl?(db,u)
 184     rows = db.execute( "SELECT uidl FROM uidls WHERE uidl = ?", account_uidl(u) )
 185     rows.length > 0
 186   end
 187
 188   # Fetch all the new messages from this POP3 account, deleting
 189   # successfully downloaded messages.
 190
 191   def fetch_all
 192
 193     if @use_ssl
 194       if @ssl_verify
 195         ssl_options = OpenSSL::SSL::VERIFY_PEER
 196       else
 197         ssl_options = OpenSSL::SSL::VERIFY_NONE
 198       end
 199       Net::POP3.enable_ssl(ssl_options)
 200    else
 201       Net::POP3.disable_ssl
 202     end
 203
 204     # Process all the messages
 205
 206     i = 0
 207     total = 0
 208
 209     while true
 210
 211       delete_list = []
 212
 213       Net::POP3.start(@host, @port, @user, @password, @use_apop) do |pop|
 214
 215         connected_at = Time.now
 216
 217         if i == 0 and not pop.mails.empty?
 218           total = pop.n_mails
 219           plural = total != 1
 220           puts "  There " + (plural ? "are" : "is") + " #{total} message" +
 221             (plural ? "s" : "") + " available."
 222         end
 223
 224         if i >= total
 225           if i == 0
 226             puts "  No mail."
 227           end
 228           return
 229         end
 230
 231         pop.each_mail do |m|
 232
 233           i += 1
 234
 235           print "  Retrieving message #{i} of #{total} [#{m.length} bytes]: "
 236
 237           uidl = m.uidl
 238           $db.transaction
 239           if db_has_uidl? $db, uidl
 240             if $keep
 241               puts " [Skipping]"
 242             else
 243               puts " [Skipping, Deleting]"
 244               m.delete
 245               delete_list.push uidl
 246             end
 247             $db.commit
 248             next
 249           end
 250
 251           progress = Progress.new(m.size)
 252
 253           # Fetch the message...
 254           message = ""
 255           m.pop do |chunk|
 256             chunk.gsub!(/\r\n/, "\n")
 257             message << chunk
 258             progress.increase_by chunk.length
 259           end
 260
 261           # Deliver the message...
 262           Kernel.open("|-", "w+") do |f|
 263             if f
 264               f.write message
 265             else
 266               begin
 267                 exec @command
 268               rescue
 269                 raise "Couldn't exec \"#{@command}\": #{$!}\n"
 270               end
 271             end
 272           end
 273
 274           if $?.success?
 275             unless add_uidl_to_db $db, uidl
 276               $db.rollback
 277               raise "Adding the UIDL to the database failed."
 278             end
 279           else
 280             $db.rollback
 281             raise "The command \"#{@command}\" failed with exit code #{$?.exitstatus}"
 282           end
 283           $db.commit
 284
 285           # We've successfully dealt with the message now...
 286           if $keep
 287             print " [Fetched]"
 288           else
 289             print " [Fetched, Deleting]"
 290             m.delete
 291             delete_list.push uidl
 292           end
 293           puts
 294
 295           if $reconnect_after and Time.now - connected_at >= $reconnect_after
 296             break
 297           end
 298
 299         end
 300       end
 301
 302       $db.transaction do |db|
 303         delete_uidls_from_db db, delete_list
 304       end
 305
 306     end
 307   end
 308
 309 end
 310
 311 # ----------------------------------------------------------------------
 312
 313 begin
 314
 315   # Make sure that the UIDL database file is present.
 316
 317   $db = SQLite3::Database.new($uidl_database_filename)
 318
 319   $db.execute( "CREATE TABLE IF NOT EXISTS uidls ( uidl TEXT PRIMARY KEY )" )
 320
 321   # Read in the configuration file...
 322
 323   accounts = open($configuration_file, "r") { |f| YAML.load(f) }
 324   raise "No accounts specified in configuration file." if accounts.length == 0
 325
 326   # This is the main loop.  Go through every account, fetching all the
 327   # new mail...
 328
 329   accounts.each_index do |i|
 330
 331     a = accounts[i]
 332
 333     # Do some quick checks on what we've just parsed...
 334
 335     valid_account_properties = ['Host', 'User', 'Pass', 'Command', 'SSL', 'APOP', 'Port']
 336
 337     (a.keys - valid_account_properties).each do |property|
 338       STDERR.puts "Warning: in account #{i + 1}, the unknown account property `#{property}' was ignored."
 339     end
 340
 341     ['Host', 'User', 'Pass'].each do |required|
 342       raise "Missing `#{required}:' line in account #{i + 1}" unless a[required]
 343       unless a[required].class == String
 344         raise "The value in the `#{required}:' property of account #{i + 1} " +
 345           "(`#{a[required].to_s}' was not interpreted as a string; you " +
 346           "may need to quote it"
 347       end
 348     end
 349
 350     ['SSL', 'APOP'].each do |boolean|
 351       if a['boolean']
 352         unless [ TrueClass, FalseClass ].include? a[boolean].class
 353           raise "In account #{i + 1}, `#{boolean}' property must be `yes', `no', `true' or `false'"
 354         end
 355       end
 356     end
 357
 358     if a['Port']
 359       unless a['Port'].class == Fixnum
 360         raise "In account #{i + 1} the Port property must be an integer (not `#{a['Port']}\')"
 361       end
 362     else
 363       a['Port'] = a['SSL'] ? 995 : 110
 364     end
 365
 366     unless a['Command']
 367       a['Command'] = 'procmail -f-'
 368     end
 369
 370     account = POP3Account.new(a['Host'], a['User'], a['Pass'], a['SSL'],
 371                               a['APOP'], a['Port'], a['Command'])
 372
 373     begin
 374       puts "Checking account: #{account}"
 375       puts "  Piping mail to the command: #{account.command}"
 376       account.fetch_all
 377     rescue Interrupt => e
 378       $db.rollback if $db.transaction_active?
 379       STDERR.puts "Interrupt received: exiting."
 380       STDERR.puts $!.backtrace
 381       break
 382     rescue
 383       $db.rollback if $db.transaction_active?
 384       STDERR.puts "  Error fetching mail from account `#{account}': #{$!}"
 385       STDERR.puts $!.backtrace
 386     end
 387
 388   end
 389
 390 rescue
 391   STDERR.puts "Fatal error: #{$!}"
 392 end