commit f5d257dff6af41dbbe33ab20c5bbb218a38c8cd8 Author: Karsten Loesing karsten.loesing@gmx.net Date: Fri Mar 25 10:29:38 2011 +0100

Add George's censorship detector script. --- task-2718/detector.py | 306 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 306 insertions(+), 0 deletions(-)

diff --git a/task-2718/detector.py b/task-2718/detector.py new file mode 100644 index 0000000..0370d02 --- /dev/null +++ b/task-2718/detector.py @@ -0,0 +1,306 @@ +## Copyright (c) 2011 George Danezis gdane@microsoft.com +## +## All rights reserved. +## +## Redistribution and use in source and binary forms, with or without +## modification, are permitted (subject to the limitations in the +## disclaimer below) provided that the following conditions are met: +## +## * Redistributions of source code must retain the above copyright +## notice, this list of conditions and the following disclaimer. +## +## * Redistributions in binary form must reproduce the above copyright +## notice, this list of conditions and the following disclaimer in the +## documentation and/or other materials provided with the +## distribution. +## +## * Neither the name of <Owner Organization> nor the names of its +## contributors may be used to endorse or promote products derived +## from this software without specific prior written permission. +## +## NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE +## GRANTED BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT +## HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED +## WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +## MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +## DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE +## LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +## CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +## SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR +## BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, +## WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE +## OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN +## IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +## +## (Clear BSD license: http://labs.metacarta.com/license-explanation.html#license) + +## This script reads a .csv file of the number of Tor users and finds +## anomalies that might be indicative of censorship. + +# Dep: matplotlib +from pylab import * +import matplotlib + +# Dep: numpy +import numpy + +# Dep: scipy +import scipy.stats +from scipy.stats.distributions import norm +from scipy.stats.distributions import poisson + +# Std lib +from datetime import date +from datetime import timedelta +import os.path + +days = ["Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"] + +# read the .csv file +class torstatstore: + def __init__(self, file_name): + f = file(file_name) + country_codes = f.readline() + country_codes = country_codes.strip().split(",") + + store = {} + MAX_INDEX = 0 + for i, line in enumerate(f): + MAX_INDEX += 1 + line_parsed = line.strip().split(",") + for j, (ccode, val) in enumerate(zip(country_codes,line_parsed)): + processed_val = None + if ccode == "date": + try: + year, month, day = int(val[:4]), int(val[5:7]), int(val[8:10]) + processed_val = date(year, month, day) + except Exception, e: + print "Parsing error (ignoring line %s):" % j + print "%s" % val,e + break + + elif val != "NA": + processed_val = int(val) + store[(ccode, i)] = processed_val + + # min and max + date_min = store[("date", 0)] + date_max = store[("date", i)] + + all_dates = [] + d = date_min + dt = timedelta(days=1) + while d <= date_max: + all_dates += [d] + d = d + dt + + # Save for later + self.store = store + self.all_dates = all_dates + self.country_codes = country_codes + self.MAX_INDEX = MAX_INDEX + self.date_min = date_min + self.date_max = date_max + + def get_country_series(self, ccode): + assert ccode in self.country_codes + series = {} + for d in self.all_dates: + series[d] = None + for i in range(self.MAX_INDEX): + series[self.store[("date", i)]] = self.store[(ccode, i)] + sx = [] + for d in self.all_dates: + sx += [series[d]] + return sx + + def get_largest(self, number): + exclude = set(["all", "??", "date"]) + l = [(self.store[(c, self.MAX_INDEX-1)], c) for c in self.country_codes if c not in exclude] + l.sort() + l.reverse() + return l[:number] + + def get_largest_locations(self, number): + l = self.get_largest(number) + res = {} + for _, ccode in l[:number]: + res[ccode] = self.get_country_series(ccode) + return res + +# Computes the difference between today and a number of days in the past +def n_day_rel(series, days): + rel = [] + for i, v in enumerate(series): + if series[i] is None: + rel += [None] + continue + + if i - days < 0 or series[i-days] is None or series[i-days] == 0: + rel += [None] + else: + rel += [ float(series[i]) / series[i-days]] + return rel + +# Main model: computes the expected min / max range of number of users +def make_tendencies_minmax(l, INTERVAL = 1): + lminus1 = dict([(ccode, n_day_rel(l[ccode], INTERVAL)) for ccode in l]) + c = lminus1[lminus1.keys()[0]] + dists = [] + minx = [] + maxx = [] + for i in range(len(c)): + vals = [lminus1[ccode][i] for ccode in lminus1.keys() if lminus1[ccode][i] != None] + if len(vals) < 8: + dists += [None] + minx += [None] + maxx += [None] + else: + vals.sort() + median = vals[len(vals)/2] + q1 = vals[len(vals)/4] + q2 = vals[(3*len(vals))/4] + qd = q2 - q1 + vals = [v for v in vals if median - qd*4 < v and v < median + qd*4] + if len(vals) < 8: + dists += [None] + minx += [None] + maxx += [None] + continue + mu, signma = norm.fit(vals) + dists += [(mu, signma)] + maxx += [norm.ppf(0.9999, mu, signma)] + minx += [norm.ppf(1 - 0.9999, mu, signma)] + ## print minx[-1], maxx[-1] + return minx, maxx + +# Makes pretty plots +def raw_plot(series, minc, maxc, labels, xtitle): + assert len(xtitle) == 3 + fname, stitle, slegend = xtitle + + font = {'family' : 'Bitstream Vera Sans', + 'weight' : 'normal', + 'size' : 8} + matplotlib.rc('font', **font) + + ylim( (-max(series)*0.1, max(series)*1.1) ) + plot(labels, series, linewidth=1.0, label="Users") + + wherefill = [] + for mm,mx in zip(minc, maxc): + wherefill += [not (mm == None and mx == None)] + assert mm < mx or (mm == None and mx == None) + + fill_between(labels, minc, maxc, where=wherefill, color="gray", label="Prediction") + + vdown = [] + vup = [] + for i,v in enumerate(series): + if minc[i] != None and v < minc[i]: + vdown += [v] + vup += [None] + elif maxc[i] != None and v > maxc[i]: + vdown += [None] + vup += [v] + else: + vup += [None] + vdown += [None] + + plot(labels, vdown, 'o', ms=10, lw=2, alpha=0.5, mfc='orange', label="Downturns") + plot(labels, vup, 'o', ms=10, lw=2, alpha=0.5, mfc='green', label="Upturns") + + legend(loc=2) + + xlabel('Time (days)') + ylabel('Users') + title(stitle) + grid(True) + F = gcf() + + F.set_size_inches(10,5) + F.savefig(fname, format="png", dpi = (150)) + close() + +def absolute_plot(series, minc, maxc, labels,INTERVAL, xtitle): + in_minc = [] + in_maxc = [] + for i, v in enumerate(series): + if i > 0 and i - INTERVAL >= 0 and series[i] != None and series[i-INTERVAL] != None and series[i-INTERVAL] != 0 and minc[i]!= None and maxc[i]!= None: + in_minc += [minc[i] * poisson.ppf(1-0.9999, series[i-INTERVAL])] + in_maxc += [maxc[i] * poisson.ppf(0.9999, series[i-INTERVAL])] + if not in_minc[-1] < in_maxc[-1]: + print in_minc[-1], in_maxc[-1], series[i-INTERVAL], minc[i], maxc[i] + assert in_minc[-1] < in_maxc[-1] + else: + in_minc += [None] + in_maxc += [None] + raw_plot(series, in_minc, in_maxc, labels, xtitle) + +# Censorship score by jurisdiction +def censor_score(series, minc, maxc, INTERVAL): + upscore = 0 + downscore = 0 + for i, v in enumerate(series): + if i > 0 and i - INTERVAL >= 0 and series[i] != None and series[i-INTERVAL] != None and series[i-INTERVAL] != 0 and minc[i]!= None and maxc[i]!= None: + in_minc = minc[i] * poisson.ppf(1-0.9999, series[i-INTERVAL]) + in_maxc = maxc[i] * poisson.ppf(0.9999, series[i-INTERVAL]) + downscore += 1 if minc[i] != None and v < in_minc else 0 + upscore += 1 if maxc[i] != None and v > in_maxc else 0 + return downscore, upscore + +def plot_target(tss, TARGET, xtitle, minx, maxx, DAYS=365, INTERV = 7): + ctarget = tss.get_country_series(TARGET) + c = n_day_rel(ctarget, INTERV) + absolute_plot(ctarget[-DAYS:], minx[-DAYS:], maxx[-DAYS:], tss.all_dates[-DAYS:],INTERV, xtitle = xtitle) + + +## Make a league table of censorship + nice graphs +def plot_all(tss, minx, maxx, INTERV, DAYS=None, rdir="img"): + rdir = os.path.realpath(rdir) + if not os.path.exists(rdir) or not os.path.isdir(rdir): + print "ERROR: %s does not exist or is not a directory." % rdir + return + + summary_file = file(os.path.join(rdir, "summary.txt"), "w") + + if DAYS == None: + DAYS = 6*31 + + s = tss.get_largest(200) + scores = [] + for num, li in s: + print ".", + ds,us = censor_score(tss.get_country_series(li)[-DAYS:], minx[-DAYS:], maxx[-DAYS:], INTERV) + # print ds, us + scores += [(ds,num, us, li)] + scores.sort() + scores.reverse() + s = "\n=======================\n" + s+= "Report for %s to %s\n" % (tss.all_dates[-DAYS], tss.all_dates[-1]) + s+= "=======================\n" + print s + summary_file.write(s) + for a,nx, b,c in scores: + if a > 0: + s = "%s -- down: %2d (up: %2d affected: %s)" % (c, a, b, nx) + print s + summary_file.write(s + "\n") + xtitle = (os.path.join(rdir, "%03d-%s-censor.png" % (a,c)), "Tor report for %s -- down: %2d (up: %2d affected: %s)" % (c, a, b, nx),"") + plot_target(tss, c,xtitle, minx, maxx, DAYS, INTERV) + summary_file.close() + +def main(): + # Change these to customize script + CSV_FILE = "direct-users.csv" + GRAPH_DIR = "img" + INTERV = 7 + DAYS= 6 * 31 + + tss = torstatstore(CSV_FILE) + l = tss.get_largest_locations(50) + minx, maxx = make_tendencies_minmax(l, INTERV) + plot_all(tss, minx, maxx, INTERV, DAYS, rdir=GRAPH_DIR) + +if __name__ == "__main__": + main()