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 fingerprint(sig):
  10         try:
  11                 return sig.fingerprint
  12         except:
  13                 # Work around a bug in injector-0.9
  14                 return sig.status[sig.FINGERPRINT]
  15
  16 def pretty_fp(fp):
  17         s = fp[0:4]
  18         for x in range(4, len(fp), 4):
  19                 s += ' ' + fp[x:x + 4]
  20         return s
  21
  22 class TrustBox(dialog.Dialog):
  23         interface = None
  24         sigs = None
  25         iface_xml = None
  26
  27         def __init__(self, interface, sigs, iface_xml):
  28                 dialog.Dialog.__init__(self)
  29                 self.connect('destroy', lambda a: _pop_queue())
  30
  31                 def left(text):
  32                         label = gtk.Label(text)
  33                         label.set_alignment(0, 0.5)
  34                         label.set_selectable(True)
  35                         return label
  36
  37                 self.interface = interface
  38                 self.sigs = sigs
  39                 self.iface_xml = iface_xml
  40
  41                 self.set_title('Confirm trust')
  42
  43                 vbox = gtk.VBox(False, 4)
  44                 vbox.set_border_width(4)
  45                 self.vbox.pack_start(vbox, True, True, 0)
  46
  47                 label = left('Checking: ' + interface.uri + '\n\n'
  48                                   'Please confirm that you trust '
  49                                   'these keys to sign software updates:')
  50                 vbox.pack_start(label, False, True, 0)
  51
  52                 notebook = gtk.Notebook()
  53                 vbox.pack_start(notebook, True, True, 0)
  54
  55                 self.add_button(gtk.STOCK_HELP, gtk.RESPONSE_HELP)
  56                 self.add_button(gtk.STOCK_CANCEL, gtk.RESPONSE_CANCEL)
  57                 self.add_button(gtk.STOCK_ADD, gtk.RESPONSE_OK)
  58                 self.set_default_response(gtk.RESPONSE_OK)
  59
  60                 valid_sigs = [s for s in sigs if isinstance(s, gpg.ValidSig)]
  61                 if not valid_sigs:
  62                         raise SafeException('No valid signatures found')
  63
  64                 trust = {}      # Sig -> CheckButton
  65                 def ok_sensitive():
  66                         trust_any = False
  67                         for toggle in trust.values():
  68                                 if toggle.get_active():
  69                                         trust_any = True
  70                                         break
  71                         self.set_response_sensitive(gtk.RESPONSE_OK, trust_any)
  72                 for sig in sigs:
  73                         if hasattr(sig, 'get_details'):
  74                                 name = '<unknown>'
  75                                 details = sig.get_details()
  76                                 for item in details:
  77                                         if item[0] in ('pub', 'uid'):
  78                                                 name = item[9]
  79                                                 break
  80                         else:
  81                                 name = None
  82                         page = gtk.VBox(False, 4)
  83                         page.set_border_width(8)
  84                         page.pack_start(left('Fingerprint: ' + pretty_fp(fingerprint(sig))), False, True, 0)
  85                         if name is not None:
  86                                 page.pack_start(left('Claimed identity: ' + name), False, True, 0)
  87
  88                         frame = gtk.Frame('Unreliable hints database says')
  89                         frame.set_border_width(4)
  90                         hint = left(hints.get(fingerprint(sig), 'Warning: Nothing known about this key!'))
  91                         hint.set_line_wrap(True)
  92                         hint.set_padding(4, 4)
  93                         frame.add(hint)
  94                         page.pack_start(frame, True, True, 0)
  95
  96                         trust[sig] = gtk.CheckButton('Trust this key')
  97                         page.pack_start(trust[sig], False, True, 0)
  98                         trust[sig].connect('toggled', lambda t: ok_sensitive())
  99
 100                         notebook.append_page(page, gtk.Label(name or 'Signature'))
 101
 102                 ok_sensitive()
 103                 self.vbox.show_all()
 104
 105                 def response(box, resp):
 106                         if resp == gtk.RESPONSE_HELP:
 107                                 trust_help.display()
 108                                 return
 109                         if resp == gtk.RESPONSE_OK:
 110                                 self.trust_keys([sig for sig in trust if trust[sig].get_active()])
 111                         self.destroy()
 112                 self.connect('response', response)
 113
 114                 self.present()
 115
 116         def trust_keys(self, sigs):
 117                 try:
 118                         for sig in sigs:
 119                                 trust.trust_db.trust_key(fingerprint(sig))
 120
 121                         if not iface_cache.update_interface_if_trusted(self.interface, self.sigs,
 122                                                                       self.iface_xml):
 123                                 raise Exception('Bug: still not trusted!!')
 124                 except Exception, ex:
 125                         dialog.alert(None, ex)
 126
 127 _queue = []
 128 def _pop_queue():
 129         if _queue:
 130                 a = _queue.pop()
 131                 a.show()
 132
 133 def confirm_trust(interface, sigs, iface_xml):
 134         _queue.append(TrustBox(interface, sigs, iface_xml))
 135         if len(_queue) == 1:
 136                 _pop_queue()
 137
 138 trust_help = help_box.HelpBox("Trust Help",
 139 ('Overview', """
 140 When you run a program, it typically has access to all your files and can generally do \
 141 anything that you're allowed to do (delete files, send emails, etc). So it's important \
 142 to make sure that you don't run anything malicious."""),
 143
 144 ('Digital signatures', """
 145 Each software author creates a 'key-pair'; a 'public key' and a 'private key'. Without going \
 146 into the maths, only something encrypted with the private key will decrypt with the public key.
 147
 148 So, when a programmer releases some software, they encrypt it with their private key (which no-one \
 149 else has). When you download it, the injector checks that it decrypts using their public key, thus \
 150 proving that it came from them and hasn't been tampered with."""),
 151
 152 ('Trust', """
 153 After the injector has checked that the software hasn't been modified since it was signed with \
 154 the private key, you still have the following problems:
 155
 156 1. Does the public key you have really belong to the author?
 157 2. Even if the software really did come from that person, do you trust them?"""),
 158
 159 ('Key fingerprints', """
 160 To confirm (1), you should compare the public key you have with the genuine one. To make this \
 161 easier, the injector displays a 'fingerprint' for the key. Look in mailing list postings or some \
 162 other source to check that the fingerprint is right (a different key will have a different \
 163 fingerprint).
 164
 165 You're trying to protect against the situation where an attacker breaks into a web site \
 166 and puts up malicious software, signed with the attacker's private key, and puts up the \
 167 attacker's public key too. If you've downloaded this software before, you \
 168 should be suspicious that you're being asked to confirm another key!"""),
 169
 170 ('Reputation', """
 171 In general, most problems seem to come from malicous and otherwise-unknown people \
 172 replacing software with modified versions, or creating new programs intended only to \
 173 cause damage. So, check your programs are signed by a key with a good reputation!"""))
 174
 175 hints = {
 176         '1DC295D11A3F910DA49D3839AA1A7812B40B0B6E' :
 177                 'Ken Hayber has been writing ROX applications since 2003. This key '
 178                 'was announced on the rox-users list on 5 Jun 2005.',
 179
 180         '4338D5420E0BAEB6B2E73530B66A4F24AB8B4B65' :
 181                 'Thomas Formella is experimenting with packaging programs for 0launch. This key '
 182                 'was announced on 11 Sep 2005 on the zero-install mailing list.',
 183
 184         '92429807C9853C0744A68B9AAE07828059A53CC1' :
 185                 'Thomas Leonard created Zero Install and ROX. This key is normally trusted by default.',
 186
 187         '0597A2AFB6B372ACB97AC6E433B938C2E9D8826D' :
 188                 'Stephen Watson is a project admin for the ROX desktop, and has been involved with the '
 189                 'project since 2000. This key has been used for signing software since the 23 Jul 2005 '
 190                 'announcement on the zero-install mailing list.',
 191 }