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 # FIXME: I don't understand the recent changes that have been made to
  40 # InternetMessageIO and broke the old version of these two classes, so
  41 # while this seems to work at the moment, I expect it to break at any
  42 # time.
  43
  44 module Net
  45
  46   class SSLIO < InternetMessageIO
  47
  48     def SSLIO.old_open(addr, port, open_timeout = 30, read_timeout = 30, debug_output = nil)
  49
  50       tcp_socket = timeout(open_timeout) { TCPsocket.new(addr, port) }
  51
  52       @ssl_context = OpenSSL::SSL::SSLContext.new()
  53
  54       if $ssl_verify
  55         @ssl_context.ca_path = '/etc/ssl/certs'
  56         @ssl_context.verify_mode = OpenSSL::SSL::VERIFY_PEER
  57       else
  58         @ssl_context.verify_mode = OpenSSL::SSL::VERIFY_NONE
  59       end
  60
  61       socket = OpenSSL::SSL::SSLSocket.new(tcp_socket, @ssl_context)
  62
  63       socket.connect
  64
  65       io = new(socket)
  66       io.read_timeout = read_timeout
  67       io.debug_output = debug_output
  68       io
  69
  70     end
  71
  72   end
  73
  74 end
  75
  76 # ----------------------------------------------------------------------
  77 #
  78 # POP3 over SSL class
  79
  80 module Net
  81
  82   class POP3s < POP3
  83
  84     def self.port
  85       '995'
  86     end
  87
  88     def POP3s.socket_type
  89       SSLIO
  90     end
  91
  92   end
  93
  94 end
  95
  96 # ----------------------------------------------------------------------
  97 #
  98 # Command line argument parsing...
  99
 100 # Some default values...
 101
 102 $configuration_file = "#{ENV['HOME']}/.stand.yaml"
 103 $configuration_file_pretty = "~/.stand.yaml"
 104 $uidl_database_filename = "#{ENV['HOME']}/.stand-uidls"
 105
 106 def usage
 107
 108   print <<EOF
 109 Usage: #{$program_name} [OPTION]...
 110
 111   -h, --help           Display this message and exit.
 112   -d, --delete         Delete messages on server after fetching.
 113   -n, --no-ssl-verify  Don\'t verify the peer\'s certificate when using SSL.
 114   -f <FILENAME>, --configuration-file=<FILENAME>
 115                        Specify the configuration file to use.
 116                        (default: #{$configuration_file_pretty})
 117   -r <SECONDS>, --reconnect-after=<SECONDS>
 118                        Reconnect to the server if <SECONDS> seconds has
 119                        elapsed since the last connection.
 120 EOF
 121
 122 end
 123
 124 options = GetoptLong.new(
 125   [ "--help", "-h", GetoptLong::NO_ARGUMENT ],
 126   [ "--delete", "-d", GetoptLong::NO_ARGUMENT ],
 127   [ "--no-ssl-verify", "-n", GetoptLong::NO_ARGUMENT ],
 128   [ "--configuration-file", "-f", GetoptLong::REQUIRED_ARGUMENT ],
 129   [ "--reconnect-after", "-r",  GetoptLong::REQUIRED_ARGUMENT ]
 130 )
 131
 132 $keep = true
 133 $ssl_verify = true
 134 $reconnect_after = nil
 135
 136 begin
 137
 138   options.each do |opt, arg|
 139
 140     case opt
 141     when "--help"
 142       usage
 143       exit
 144     when "--delete"
 145       $keep = false
 146     when "--no-ssl-verify"
 147       $ssl_verify = false
 148     when "--configuration-file"
 149       $configuration_file = arg
 150     when "--reconnect-after"
 151       $reconnect_after = Float(arg)
 152     end
 153
 154   end
 155
 156 rescue
 157
 158   print "Bad command line option: " + $! + "\n"
 159   usage
 160   exit
 161
 162 end
 163
 164 if $keep and $reconnect_after
 165   puts "There should be no reason to specify --reconnect-after with --keep"
 166   exit
 167 end
 168
 169 # ----------------------------------------------------------------------
 170
 171 # A fairly idiotic progress class.
 172
 173 class Progress
 174
 175   def initialize(maximum)
 176     @maximum = maximum
 177     @current_value = 0
 178   end
 179
 180   def increase_by(i)
 181     set @current_value + i
 182   end
 183
 184   def set(v)
 185     block_change = (v / 1024) - (@current_value / 1024)
 186     if block_change >= 0
 187       (1..block_change).each { print "." }
 188       $stdout.flush
 189     else
 190       backspaces = - block_change
 191       (1..backspaces).each { print "\b" }
 192       $stdout.flush
 193     end
 194     @current_value = v
 195   end
 196
 197 end
 198
 199 # ----------------------------------------------------------------------
 200
 201 # This class deals with connecting to a POP3 server, and fetching the
 202 # mail from it.
 203
 204 class POP3Account
 205
 206   attr_accessor :host, :user, :port
 207
 208   attr_reader :command
 209
 210   def initialize(host, user, password, use_ssl, use_apop, port, command)
 211     @host = host
 212     @user = user
 213     @password = password
 214     @use_ssl = use_ssl
 215     @use_apop = use_apop
 216     @port = port
 217     @command = command
 218   end
 219
 220   def to_s
 221     "#{@user} at #{@host}:#{@port}#{ @use_ssl ? ' (SSL)' : ''}"
 222   end
 223
 224   def account_uidl(uidl)
 225     "#{@user}@#{@host}:#{@port}##{uidl}"
 226   end
 227
 228   # These three methods manipulate the UIDL database.
 229
 230   def add_uidl_to_db(db,u)
 231     db.execute( "INSERT INTO uidls VALUES (?)", account_uidl(u) )
 232   end
 233
 234   def delete_uidls_from_db(db,a)
 235     a.each do |u|
 236       db.execute( "DELETE FROM uidls WHERE uidl = ?", account_uidl(u) )
 237     end
 238   end
 239
 240   def db_has_uidl?(db,u)
 241     rows = db.execute( "SELECT uidl FROM uidls WHERE uidl = ?", account_uidl(u) )
 242     rows.length > 0
 243   end
 244
 245   # Fetch all the new messages from this POP3 account, deleting
 246   # successfully downloaded messages.
 247
 248   def fetch_all
 249
 250     # Choose correct POP class
 251
 252     if @use_ssl
 253       pop3_class = Net::POP3s
 254     else
 255       pop3_class = Net::POP3
 256     end
 257
 258     # Process all the messages
 259
 260     i = 0
 261     total = 0
 262
 263     while true
 264
 265       delete_list = []
 266
 267       pop3_class.start(@host, @port, @user, @password, @use_apop) do |pop|
 268
 269         connected_at = Time.now
 270
 271         if i == 0 and not pop.mails.empty?
 272           total = pop.n_mails
 273           plural = total != 1
 274           puts "  There " + (plural ? "are" : "is") + " #{total} message" +
 275             (plural ? "s" : "") + " available."
 276         end
 277
 278         if i >= total
 279           if i == 0
 280             puts "  No mail."
 281           end
 282           return
 283         end
 284
 285         pop.each_mail do |m|
 286
 287           i += 1
 288
 289           print "  Retrieving message #{i} of #{total} [#{m.length} bytes]: "
 290
 291           uidl = m.uidl
 292           $db.transaction
 293           if db_has_uidl? $db, uidl
 294             if $keep
 295               puts " [Skipping]"
 296             else
 297               puts " [Skipping, Deleting]"
 298               m.delete
 299               delete_list.push uidl
 300             end
 301             $db.commit
 302             next
 303           end
 304
 305           progress = Progress.new(m.size)
 306
 307           # Fetch the message...
 308           message = ""
 309           m.pop do |chunk|
 310             chunk.gsub!(/\r\n/, "\n")
 311             message << chunk
 312             progress.increase_by chunk.length
 313           end
 314
 315           # Deliver the message...
 316           Kernel.open("|-", "w+") do |f|
 317             if f
 318               f.write message
 319             else
 320               begin
 321                 exec @command
 322               rescue
 323                 raise "Couldn't exec \"#{@command}\": #{$!}\n"
 324               end
 325             end
 326           end
 327
 328           if $?.success?
 329             unless add_uidl_to_db $db, uidl
 330               $db.rollback
 331               raise "Adding the UIDL to the database failed."
 332             end
 333           else
 334             $db.rollback
 335             raise "The command \"#{@command}\" failed with exit code #{$?.exitstatus}"
 336           end
 337           $db.commit
 338
 339           # We've successfully dealt with the message now...
 340           if $keep
 341             print " [Fetched]"
 342           else
 343             print " [Fetched, Deleting]"
 344             m.delete
 345             delete_list.push uidl
 346           end
 347           puts
 348
 349           if $reconnect_after and Time.now - connected_at >= $reconnect_after
 350             break
 351           end
 352
 353         end
 354       end
 355
 356       $db.transaction do |db|
 357         delete_uidls_from_db db, delete_list
 358       end
 359
 360     end
 361   end
 362
 363 end
 364
 365 # ----------------------------------------------------------------------
 366
 367 begin
 368
 369   # Make sure that the UIDL database file is present.
 370
 371   $db = SQLite3::Database.new($uidl_database_filename)
 372
 373   $db.execute( "CREATE TABLE IF NOT EXISTS uidls ( uidl TEXT PRIMARY KEY )" )
 374
 375   # Read in the configuration file...
 376
 377   accounts = open($configuration_file, "r") { |f| YAML.load(f) }
 378   raise "No accounts specified in configuration file." if accounts.length == 0
 379
 380   # This is the main loop.  Go through every account, fetching all the
 381   # new mail...
 382
 383   accounts.each_index do |i|
 384
 385     a = accounts[i]
 386
 387     # Do some quick checks on what we've just parsed...
 388
 389     valid_account_properties = ['Host', 'User', 'Pass', 'Command', 'SSL', 'APOP', 'Port']
 390
 391     (a.keys - valid_account_properties).each do |property|
 392       puts "Warning: in account #{i + 1}, the unknown account property `#{property}' was ignored."
 393     end
 394
 395     ['Host', 'User', 'Pass'].each do |required|
 396       raise "Missing `#{required}:' line in account #{i + 1}" unless a[required]
 397       unless a[required].class == String
 398         raise "The value in the `#{required}:' property of account #{i + 1} " +
 399           "(`#{a[required].to_s}' was not interpreted as a string; you " +
 400           "may need to quote it"
 401       end
 402     end
 403
 404     ['SSL', 'APOP'].each do |boolean|
 405       if a['boolean']
 406         unless [ TrueClass, FalseClass ].include? a[boolean].class
 407           raise "In account #{i + 1}, `#{boolean}' property must be `yes', `no', `true' or `false'"
 408         end
 409       end
 410     end
 411
 412     if a['Port']
 413       unless a['Port'].class == Fixnum
 414         raise "In account #{i + 1} the Port property must be an integer (not `#{a['Port']}\')"
 415       end
 416     else
 417       a['Port'] = a['SSL'] ? 995 : 110
 418     end
 419
 420     unless a['Command']
 421       a['Command'] = 'procmail -f-'
 422     end
 423
 424     account = POP3Account.new(a['Host'], a['User'], a['Pass'], a['SSL'],
 425                               a['APOP'], a['Port'], a['Command'])
 426
 427     begin
 428       puts "Checking account: #{account}"
 429       puts "  Piping mail to the command: #{account.command}"
 430       account.fetch_all
 431     rescue Interrupt
 432       $db.rollback if $db.transaction_active?
 433       puts "Interrupt received: exiting."
 434       break
 435     rescue
 436       $db.rollback if $db.transaction_active?
 437       puts "  Error fetching mail from account `#{account}': " + $!
 438     end
 439
 440   end
 441
 442 rescue
 443   puts "Fatal error: " + $!
 444 end