trust_box.py

   1 import gtk
   2 from zeroinstall.injector.model import SafeException
   3 from zeroinstall.injector import gpg, trust
   4 from zeroinstall.injector.iface_cache import iface_cache
   5
   6 import gui
   7 import dialog, help_box
   8
   9 def pretty_fp(fp):
  10         s = fp[0:4]
  11         for x in range(4, len(fp), 4):
  12                 s += ' ' + fp[x:x + 4]
  13         return s
  14
  15 class TrustBox(dialog.Dialog):
  16         model = None
  17         tree_view = None
  18
  19         interface = None
  20         sigs = None
  21         iface_xml = None
  22
  23         def __init__(self, interface, sigs, iface_xml):
  24                 dialog.Dialog.__init__(self)
  25                 self.connect('destroy', lambda a: _pop_queue())
  26
  27                 self.interface = interface
  28                 self.sigs = sigs
  29                 self.iface_xml = iface_xml
  30
  31                 self.set_title('Confirm trust')
  32
  33                 label = gtk.Label('Please confirm that you trust '
  34                                   'these keys to sign software updates:')
  35                 label.set_padding(8, 8)
  36                 self.vbox.pack_start(label, False, True, 0)
  37
  38                 swin = gtk.ScrolledWindow()
  39                 self.vbox.pack_start(swin, True, True, 0)
  40                 swin.set_policy(gtk.POLICY_NEVER, gtk.POLICY_AUTOMATIC)
  41                 swin.set_shadow_type(gtk.SHADOW_IN)
  42                 swin.set_border_width(8)
  43
  44                 self.model = gtk.ListStore(str, object)
  45                 self.tree_view = gtk.TreeView(self.model)
  46                 self.tree_view.get_selection().set_mode(gtk.SELECTION_NONE)
  47                 swin.add(self.tree_view)
  48
  49                 self.tree_view.set_size_request(-1, 100)
  50
  51                 text = gtk.CellRendererText()
  52
  53                 for column in [gtk.TreeViewColumn('Key fingerprint', text, text = 0)]:
  54                         self.tree_view.append_column(column)
  55
  56                 self.vbox.show_all()
  57
  58                 self.add_button(gtk.STOCK_HELP, gtk.RESPONSE_HELP)
  59                 self.add_button(gtk.STOCK_CANCEL, gtk.RESPONSE_CANCEL)
  60                 self.add_button(gtk.STOCK_ADD, gtk.RESPONSE_OK)
  61                 self.set_default_response(gtk.RESPONSE_OK)
  62
  63                 def response(box, resp):
  64                         if resp == gtk.RESPONSE_HELP:
  65                                 trust_help.display()
  66                                 return
  67                         if resp == gtk.RESPONSE_OK:
  68                                 self.trust_keys()
  69                         self.destroy()
  70                 self.connect('response', response)
  71
  72                 valid_sigs = [s for s in sigs if isinstance(s, gpg.ValidSig)]
  73                 if not valid_sigs:
  74                         raise SafeException('No valid signatures found')
  75
  76                 for sig in sigs:
  77                         titer = self.model.append()
  78                         self.model[titer][0] = pretty_fp(sig.fingerprint)
  79                         self.model[titer][1] = sig
  80
  81                 self.tree_view.expand_all()
  82                 self.present()
  83
  84         def trust_keys(self):
  85                 for row in self.model:
  86                         sig = row[1]
  87                         trust.trust_db.trust_key(sig.fingerprint)
  88
  89                 if not iface_cache.update_interface_if_trusted(self.interface, self.sigs,
  90                                                               self.iface_xml):
  91                         raise Exception('Bug: still not trusted!!')
  92
  93 _queue = []
  94 def _pop_queue():
  95         if _queue:
  96                 a = _queue.pop()
  97                 a.show()
  98
  99 def confirm_trust(interface, sigs, iface_xml):
 100         _queue.append(TrustBox(interface, sigs, iface_xml))
 101         if len(_queue) == 1:
 102                 _pop_queue()
 103
 104 trust_help = help_box.HelpBox("Trust Help",
 105 ('Overview', """
 106 When you run a program, it typically has access to all your files and can generally do \
 107 anything that you're allowed to do (delete files, send emails, etc). So it's important \
 108 to make sure that you don't run anything malicious."""),
 109
 110 ('Digital signatures', """
 111 Each software author creates a 'key-pair'; a 'public key' and a 'private key'. Without going \
 112 into the maths, only something encrypted with the private key will decrypt with the public key.
 113
 114 So, when a programmer releases some software, they encrypt it with their private key (which no-one \
 115 else has). When you download it, the injector checks that it decrypts using their public key, thus \
 116 proving that it came from them and hasn't been tampered with."""),
 117
 118 ('Trust', """
 119 After the injector has checked that the software hasn't been modified since it was signed with \
 120 the private key, you still have the following problems:
 121
 122 1. Does the public key you have really belong to the author?
 123 2. Even if the software really did come from that person, do you trust them?"""),
 124
 125 ('Key fingerprints', """
 126 To confirm (1), you should compare the public key you have with the genuine one. To make this \
 127 easier, the injector displays a 'fingerprint' for the key. Look in mailing list postings or some \
 128 other source to check that the fingerprint is right (a different key will have a different \
 129 fingerprint).
 130
 131 You're trying to protect against the situation where an attacker breaks into a web site \
 132 and puts up malicious software, signed with the attacker's private key, and puts up their \
 133 public key too. If you've downloaded the real software before, you should be suspicious that \
 134 the fingerprint has changed!"""),
 135
 136 ('Reputation', """
 137 In general, most problems seem to come from malicous and otherwise-unknown people \
 138 replacing software with modified versiosn, or creating new programs intended only to \
 139 cause damage. So, check your programs are signed by a key with a good reputation!"""))