commit 4391e65f226f9b45ceaa08465f466903de14f8e0 Author: Arturo Filastò hellais@torproject.org Date: Wed Jul 11 12:54:09 2012 +0200

Add some documentation to b0wser protocol and server --- oonib/b0wser.py | 39 +++++++++++++++++++++++++++++++++++++++ 1 files changed, 39 insertions(+), 0 deletions(-)

diff --git a/oonib/b0wser.py b/oonib/b0wser.py index 6da1997..4b01cc7 100644 --- a/oonib/b0wser.py +++ b/oonib/b0wser.py @@ -5,6 +5,12 @@ from ooni.plugoo import reports from ooni.protocols.b0wser import Mutator

class B0wserProtocol(protocol.Protocol): + """ + This implements the B0wser protocol for the server side. + It gets instanced once for every client that connects to the oonib. + For every instance of protocol there is only 1 mutation. + Once the last step is reached the connection is closed on the serverside. + """ steps = [{'data': "STEP1", 'wait': 4}, {'data': "STEP2", 'wait': 4}, {'data': "STEP3", 'wait': 4}] @@ -16,12 +22,22 @@ class B0wserProtocol(protocol.Protocol): report = reports.Report('b0wser', 'b0wser.yamlooni')

def next_state(self): + """ + This is called once I have completed one step of the protocol and need + to proceed to the next step. + """ data = self.mutator.get_mutation(self.state) self.transport.write(data) self.state += 1 self.received_data = 0

def dataReceived(self, data): + """ + This is called every time some data is received. I transition to the + next step once the amount of data that I expect to receive is received. + + @param data: the data that has been sent by the client. + """ if len(self.steps) <= self.state: self.transport.loseConnection() return @@ -31,6 +47,17 @@ class B0wserProtocol(protocol.Protocol): self.next_state()

def censorship_detected(self, report): + """ + I have detected the possible presence of censorship we need to write a + report on it. + + @param report: a dict containing the report to be written. Must contain + the keys 'reason', 'proto_state' and 'mutator_state'. + The reason is the reason for which the connection was + closed. The proto_state is the current state of the + protocol instance and mutator_state is what was being + mutated. + """ print "The connection was closed because of %s" % report['reason'] print "I may have matched the censorship fingerprint" print "State %s, Mutator %s" % (report['proto_state'], @@ -39,6 +66,10 @@ class B0wserProtocol(protocol.Protocol):

def connectionLost(self, reason): + """ + The connection was closed. This may be because of a legittimate reason + or it may be because of a censorship event. + """ report = {'reason': reason, 'proto_state': self.state, 'mutator_state': self.mutator.state(), 'trigger': None}

@@ -53,6 +84,14 @@ class B0wserProtocol(protocol.Protocol): self.censorship_detected(report)

class B0wserServer(protocol.ServerFactory): + """ + This is the main class that deals with the b0wser server side component. + We keep track of global state of every client here. + Every client is identified by their IP address and the state of mutation is + stored by using their IP address as a key. This may lead to some bugs if + two different clients are sharing the same IP, but hopefully the + probability of such thing is not that likely. + """ protocol = B0wserProtocol mutations = {} def buildProtocol(self, addr):