commit 03aa67dcb5589e626306e89ef3dc92eb9c300de8 Author: Damian Johnson atagar@torproject.org Date: Wed Apr 27 21:13:05 2011 -0700

fix: Misparsing circut paths for Tor < 0.2.2.1

For Tor versions prior to 0.2.2.1 our circuit paths could contain nickname-only entries. These were being misparsed (expecting them to always start with fingerprints), resulting in screwed up circuit entries in the connection panel. Caught by asn. --- src/util/torTools.py | 67 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/src/util/torTools.py b/src/util/torTools.py index 5d8ffd8..b527f1e 100644 --- a/src/util/torTools.py +++ b/src/util/torTools.py @@ -330,6 +330,7 @@ class Controller(TorCtl.PostEventListener): self._fingerprintLookupCache = {} # lookup cache with (ip, port) -> fingerprint mappings self._fingerprintsAttachedCache = None # cache of relays we're connected to self._nicknameLookupCache = {} # lookup cache with fingerprint -> nickname mappings + self._nicknameToFpLookupCache = {} # lookup cache with nickname -> fingerprint mappings self._consensusLookupCache = {} # lookup cache with network status entries self._descriptorLookupCache = {} # lookup cache with relay descriptors self._isReset = False # internal flag for tracking resets @@ -389,6 +390,7 @@ class Controller(TorCtl.PostEventListener): self._fingerprintLookupCache = {} self._fingerprintsAttachedCache = None self._nicknameLookupCache = {} + self._nicknameToFpLookupCache = {} self._consensusLookupCache = {} self._descriptorLookupCache = {}

@@ -1164,6 +1166,44 @@ class Controller(TorCtl.PostEventListener):

return result

+ def getNicknameFingerprint(self, relayNickname): + """ + Provides the fingerprint associated with the given relay. This provides + None if no such relay exists. + + Arguments: + relayNickname - nickname of the relay + """ + + self.connLock.acquire() + + result = None + if self.isAlive(): + # determine the nickname if it isn't yet cached + if not relayNickname in self._nicknameToFpLookupCache: + # Fingerprints are base64 encoded hex with an extra '='. For instance... + # GETINFO ns/name/torexp2 -> + # r torexp2 NPfjt8Vjr+drcbbFLQONN3KapNo LxoHteGax7ZNYh/9g/FF8I617fY 2011-04-27 15:20:35 141.161.20.50 9001 0 + # decode base64 of "NPfjt8Vjr+drcbbFLQONN3KapNo=" -> + # "4\xf7\xe3\xb7\xc5c\xaf\xe7kq\xb6\xc5-\x03\x8d7r\x9a\xa4\xda" + # encode hex of the above -> + # "34f7e3b7c563afe76b71b6c52d038d37729aa4da" + + relayFingerprint = None + consensusEntry = self.getInfo("ns/name/%s" % relayNickname) + if consensusEntry: + encodedFp = consensusEntry.split()[2] + decodedFp = (encodedFp + "=").decode('base64').encode('hex') + relayFingerprint = decodedFp.upper() + + self._nicknameToFpLookupCache[relayNickname] = relayFingerprint + + result = self._nicknameToFpLookupCache[relayNickname] + + self.connLock.release() + + return result + def addEventListener(self, listener): """ Directs further tor controller events to callback functions of the @@ -1433,6 +1473,7 @@ class Controller(TorCtl.PostEventListener): self._fingerprintLookupCache = {} self._fingerprintsAttachedCache = None self._nicknameLookupCache = {} + self._nicknameToFpLookupCache = {} self._consensusLookupCache = {}

if self._fingerprintMappings != None: @@ -1870,6 +1911,12 @@ class Controller(TorCtl.PostEventListener): # 91 BUILT $E4AE6E2FE320FBBD31924E8577F3289D4BE0B4AD=Qwerty PURPOSE=GENERAL # would belong to a single hop circuit, most likely fetching the # consensus via a directory mirror. + # + # The path is made up of "$<fingerprint>[=<nickname]" entries for new + # versions of Tor, but in versions prior to 0.2.2.1-alpha this was + # just "$<fingerprint>" OR <nickname>. The dolar sign can't be used in + # nicknames so this can be used to differentiate. + circStatusResults = self.getInfo("circuit-status")

if circStatusResults == "": @@ -1885,8 +1932,24 @@ class Controller(TorCtl.PostEventListener): # 5 LAUNCHED PURPOSE=TESTING if len(lineComp) < 4: continue

- path = tuple([hopEntry[1:41] for hopEntry in lineComp[2].split(",")]) - result.append((int(lineComp[0]), lineComp[1], lineComp[3][8:], path)) + path = [] + for hopEntry in lineComp[2].split(","): + if hopEntry[0] == "$": path.append(hopEntry[1:41]) + else: + relayFingerprint = self.getNicknameFingerprint(hopEntry) + + # It shouldn't be possible for this lookup to fail, but we + # need to fill something (callers won't expect our own client + # paths to have unknown relays). If this turns out to be wrong + # then log a warning. + + if relayFingerprint: path.append(relayFingerprint) + else: + msg = "Unable to determine the fingerprint for a relay in our own circuit: %s" % hopEntry + log.log(log.WARN, msg) + path.append("0" * 40) + + result.append((int(lineComp[0]), lineComp[1], lineComp[3][8:], tuple(path))) elif key == "hsPorts": result = [] hsOptions = self.getOptionMap("HiddenServiceOptions")