Index: tracspamfilter/api.py =================================================================== --- tracspamfilter/api.py (revision 4114) +++ tracspamfilter/api.py (working copy) @@ -22,7 +22,7 @@ import textwrap import time -from trac.config import BoolOption, IntOption +from trac.config import BoolOption, IntOption, ExtensionOption from trac.core import * from trac.db import DatabaseManager from trac.env import IEnvironmentSetupParticipant @@ -61,10 +61,19 @@ """ +class IRejectHandler(Interface): + """Handle content rejection.""" + + def reject_content(req, reason): + """Reject content. `reason` is a human readable message describing why + the content was rejected. """ + + class FilterSystem(Component): strategies = ExtensionPoint(IFilterStrategy) - implements(IEnvironmentSetupParticipant, IPermissionRequestor) + implements(IEnvironmentSetupParticipant, IPermissionRequestor, + IRejectHandler) min_karma = IntOption('spam-filter', 'min_karma', '0', """The minimum score required for a submission to be allowed.""") @@ -81,6 +90,14 @@ """Whether content submissions by authenticated users should be trusted without checking for potential spam or other abuse.""") + reject_handler = ExtensionOption('spam-filter', 'reject_handler', + IRejectHandler, 'FilterSystem', + """The handler used to reject content.""") + + # IRejectHandler methods + def reject_content(self, req, message): + raise RejectContent(message) + # Public methods def test(self, req, author, changes): @@ -140,7 +157,8 @@ msg = ', '.join([r[2] for r in reasons if r[1] < 0]) if msg: msg = ' (%s)' % msg - raise RejectContent('Submission rejected as potential spam%s' % msg) + self.reject_handler.reject_content(req, 'Submission rejected as ' + 'potential spam %s' % msg) def train(self, req, log_id, spam=True): environ = {} Index: tracspamfilter/captcha/api.py =================================================================== --- tracspamfilter/captcha/api.py (revision 0) +++ tracspamfilter/captcha/api.py (revision 0) @@ -0,0 +1,75 @@ +import time +from pickle import loads, dumps +from trac.core import * +from trac.config import * +from trac.web.chrome import ITemplateProvider +from trac.web.api import IRequestFilter, IRequestHandler +from tracspamfilter.api import IRejectHandler + + +class ICaptchaMethod(Interface): + """ A captcha implementation. """ + def generate_captcha(req): + """ Return a tuple of `(result, html)`, where `result` is the expected + response and `html` is a HTML fragment for displaying the captcha + challenge. """ + + +class CaptchaVerification(Component): + implements(ITemplateProvider, IRequestHandler, IRejectHandler) + + request_handlers = ExtensionPoint(IRequestHandler) + captcha = ExtensionOption('spam-filter', 'captcha', ICaptchaMethod, + 'ExpressionCaptcha', + """ Captcha method to use for verifying humans. """) + + # IRejectHandler methods + def reject_content(self, req, message): + if not int(req.session.get('captcha_verified', 0)): + req.session['reject_reason'] = message + req.session['captcha_redirect'] = req.href(req.path_info) + req.redirect(req.href.captcha()) + + # IRequestHandler methods + def match_request(self, req): + return req.path_info == '/captcha' + + def process_request(self, req): + if req.method == 'POST': + self.env.log.debug('Captcha response: %s (expected %s)' % + (req.args['captcha_response'], req.session['captcha_expected'])) + if req.args['captcha_response'] == req.session['captcha_expected']: + redirect = req.session.get('captcha_redirect', req.href()) + del req.session['captcha_redirect'] + del req.session['captcha_expected'] + req.session['captcha_verified'] = 1 + req.redirect(redirect) + else: + req.hdf['error'] = 'Captcha verification failed' + else: + req.hdf['error'] = req.session.get('reject_reason') + result, html = self.captcha.generate_captcha(req) + req.hdf['captcha.challenge'] = html + req.hdf['captcha.href'] = req.href('captcha') + req.session['captcha_expected'] = result + req.session.save() + return 'verify_captcha.cs', None + + # ITemplateProvider methods + def get_templates_dirs(self): + """ Return the absolute path of the directory containing the provided + ClearSilver templates. """ + from pkg_resources import resource_filename + return [resource_filename(__name__, 'templates')] + + + # IRequestFilter methods + def pre_process_request(self, req, handler): + # TODO Allow restrict_to to specify request paths to allow + if not self.trust_authenticated and req.method == 'POST' \ + and handler is not self: + return Intercept(handler) + return handler + + def post_process_request(self, req, template, content_type): + return (template, content_type) Property changes on: tracspamfilter/captcha/api.py ___________________________________________________________________ Name: svn:eol-style + native Index: tracspamfilter/captcha/__init__.py =================================================================== --- tracspamfilter/captcha/__init__.py (revision 0) +++ tracspamfilter/captcha/__init__.py (revision 0) @@ -0,0 +1 @@ +from tracspamfilter.captcha.api import * Property changes on: tracspamfilter/captcha/__init__.py ___________________________________________________________________ Name: svn:eol-style + native Index: tracspamfilter/captcha/expression.py =================================================================== --- tracspamfilter/captcha/expression.py (revision 0) +++ tracspamfilter/captcha/expression.py (revision 0) @@ -0,0 +1,46 @@ +import random +from trac.core import * +from trac.config import * +from trac.util.html import html, Markup +from tracspamfilter.captcha import ICaptchaMethod + + +class ExpressionCaptcha(Component): + """ Implementation of a captcha in the form of a human readable numeric + expression. Initial implementation by sergeych@tancher.com. """ + + implements(ICaptchaMethod) + + terms = IntOption('numeric-captcha', 'terms', 3, + """ Number of terms in expression. """) + ceiling = IntOption('numeric-captcha', 'ceiling', 10, + """ Maximum value of individual terms in expression. """) + + operations = {'*': 'multiplied by', '-': 'minus', '+': 'plus'} + numerals = ('zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', + 'eight', 'nine', 'ten', 'eleven', 'twelve', 'thirteen', + 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', + 'nineteen' ) + tens = ('twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', + 'eighty', 'ninety') + + # ICaptchaMethod methods + def generate_captcha(self, req): + if self.ceiling > 100: + raise TracError('Numeric captcha can not represent numbers > 100') + terms = [str(random.randrange(0, self.ceiling)) for _ in xrange(self.terms)] + operations = [random.choice(self.operations.keys()) for _ in xrange(self.terms)] + expression = sum(zip(terms, operations), ())[:-1] + expression = eval(compile(' '.join(expression), 'captcha_eval', 'eval')) + human = sum(zip([self.humanise(int(t)) for t in terms], + [self.operations[o] for o in operations]), ())[:-1] + return (expression, html.blockquote(' '.join(map(str, human)))) + + # Internal methods + def humanise(self, value): + if value < 20: + return self.numerals[value] + english = self.tens[value / 10 - 2] + if value % 10: + english += ' ' + self.numerals[value % 10] + return english Property changes on: tracspamfilter/captcha/expression.py ___________________________________________________________________ Name: svn:eol-style + native Index: tracspamfilter/captcha/image.py =================================================================== --- tracspamfilter/captcha/image.py (revision 0) +++ tracspamfilter/captcha/image.py (revision 0) @@ -0,0 +1,78 @@ +import os +import random +import Image +import ImageFont +import ImageDraw +import ImageFilter +from StringIO import StringIO +from trac.core import * +from trac.util.html import html +from trac.config import * +from trac.web.api import IRequestHandler +from tracspamfilter.captcha import ICaptchaMethod + + +class ImageCaptcha(Component): + """ An image captcha courtesy of + http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/440588 """ + + implements(ICaptchaMethod) + implements(IRequestHandler) + + fonts = ListOption('image-captcha', 'fonts', 'vera.ttf', + doc=""" Set of fonts to choose from. """) + font_size = IntOption('image-captcha', 'font_size', 25, + "Font size") + alphabet = Option('image-captcha', 'alphabet', 'abcdefghkmnopqrstuvwxyz', + """ Alphabet to choose captcha challenge from. """) + letters = IntOption('image-captcha', 'letters', 6, + """ Number of letters to use in challenge. """) + + # IRequestHandler methods + def match_request(self, req): + return req.path_info == '/captcha/image' + + def process_request(self, req): + if 'captcha_expected' not in req.session: + # TODO Probably need to render an error image here + raise TracError('No Captcha response in session') + req.send_response(200) + req.send_header('Content-Type', 'image/jpeg') + req.end_headers() + + image = StringIO() + from pkg_resources import resource_filename + font = os.path.join(resource_filename('tracspamfilter', 'fonts'), + random.choice(self.fonts)) + self.gen_captcha(image, req.session['captcha_expected'], font, + self.font_size) + req.write(image.getvalue()) + + # ICaptchaMethod methods + def generate_captcha(self, req): + challenge = ''.join([random.choice(self.alphabet) for _ in xrange(self.letters)]) + return challenge, html.blockquote(html.img(src=req.href('/captcha/image'))) + + # Internal methods + def gen_captcha(self, file, text, fnt, fnt_sz, fmt='JPEG'): + # randomly select the foreground color + fgcolor = random.randint(0,0xffff00) + # make the background color the opposite of fgcolor + bgcolor = fgcolor ^ 0xffffff + # create a font object + font = ImageFont.truetype(fnt,fnt_sz) + # determine dimensions of the text + dim = font.getsize(text) + # create a new image slightly larger that the text + im = Image.new('RGB', (dim[0]+5,dim[1]+5), bgcolor) + d = ImageDraw.Draw(im) + x, y = im.size + r = random.randint + # draw 100 random colored boxes on the background + for num in range(100): + d.rectangle((r(0,x),r(0,y),r(0,x),r(0,y)),fill=r(0,0xffffff)) + # add the text to the image + d.text((3,3), text, font=font, fill=fgcolor) + im = im.filter(ImageFilter.EDGE_ENHANCE_MORE) + # save the image to a file + im.save(file, format=fmt) Property changes on: tracspamfilter/captcha/image.py ___________________________________________________________________ Name: svn:eol-style + native Index: tracspamfilter/captcha/captchasdotnet.py =================================================================== --- tracspamfilter/captcha/captchasdotnet.py (revision 0) +++ tracspamfilter/captcha/captchasdotnet.py (revision 0) @@ -0,0 +1,277 @@ +import os +import md5 +import random +import time +from trac.core import * +from trac.config import * +from trac.util.html import html +from tracspamfilter.captcha import ICaptchaMethod + + +class CaptchasDotNetCaptcha(Component): + """ Trac adapter for the captcha.net Captcha community site. `client` and + `secret` '''must''' be configured in the `captchas.net` section of + `trac.ini`. """ + implements(ICaptchaMethod) + + client = Option('captchas.net', 'client', doc= + """ [http://captchas.net] registered client name ('''required''') """) + secret = Option('captchas.net', 'secret', doc= + """ [http://captchas.net] registered client secret ('''required''') """) + alphabet = Option('captchas.net', 'alphabet', 'abcdefghkmnopqrstuvwxyz', + """ Alphabet to choose captcha challenge from. """) + letters = IntOption('captchas.net', 'letters', 6, + """ Number of letters to use in challenge. """) + width = IntOption('captchas.net', 'width', 240, + """ Width of captcha. """) + height = IntOption('captchas.net', 'height', 80, + """ Height of captcha. """) + random_repository = Option('captchas.net', 'random_repository', + '/tmp/captchasnet-random-strings', + """ Local captcha cache directory. """) + cleanup_time = IntOption('captchas.net', 'cleanup_time', 3600, + """ Delay, in seconds, before old captcha images are removed. """) + + # ICaptchaMethod methods + def generate_captcha(self, req): + if not self.client or not self.secret: + raise TracError('captchas.net plugin not configured (`[captchas.net] client = xxx secret = yyy)') + captcha = CaptchasDotNet(self.client, self.secret, self.alphabet, + self.letters, self.width, self.height, + self.random_repository, self.cleanup_time) + challenge = captcha.random() + html = html.p('Please respond with the letters in the following image or sound:')( + Markup(captchas.image()), + html.a('Phonetic spelling', href=captchas.audio_url()) + ) + return (challenge, html) + + +#--------------------------------------------------------------------- +# Python module for easy utilization of http://captchas.net +# +# For documentation look at http://captchas.net/sample/python/ +# +# Written by Sebastian Wilhelmi and +# Felix Holderied +# This file is in the public domain. +# +# ChangeLog: +# +# 2006-09-08: Add new optional parameters alphabet, letters +# height an width. Add audio_url. +# +# 2006-03-01: Only delete the random string from the repository in +# case of a successful verification. +# +# 2006-02-14: Add new image() method returning an HTML/JavaScript +# snippet providing a fault tolerant service. +# +# 2005-06-02: Initial version. +# +#--------------------------------------------------------------------- + +class CaptchasDotNet: + def __init__ (self, client, secret, + alphabet = 'abcdefghkmnopqrstuvwxyz', + letters = 6, + width = 240, + height = 80, + random_repository = '/tmp/captchasnet-random-strings', + cleanup_time = 3600 + ): + self.__client = client + self.__secret = secret + self.__alphabet = alphabet + self.__letters = letters + self.__width = width + self.__height = height + self.__random_repository = random_repository + self.__cleanup_time = cleanup_time + self.__time_stamp_file = os.path.join (random_repository, + '__time_stamp__') + + # Return a random string + def __random_string (self): + # The random string shall consist of small letters, big letters + # and digits. + letters = "abcdefghijklmnopqrstuvwxyz" + letters += letters.upper () + "0123456789" + + # The random starts out empty, then 40 random possible characters + # are appended. + random_string = '' + for i in range (40): + random_string += random.choice (letters) + + # Return the random string. + return random_string + + # Create a new random string and register it. + def random (self): + # If the repository directory is does not yet exist, create it. + if not os.path.isdir (self.__random_repository): + os.makedirs (self.__random_repository) + + # If the time stamp file does not yet exist, create it. + if not os.path.isfile (self.__time_stamp_file): + os.close (os.open (self.__time_stamp_file, os.O_CREAT, 0700)) + + # Get the current time. + now = time.time () + + # Determine the time, before which to remove random strings. + cleanup_time = now - self.__cleanup_time + + # If the last cleanup is older than specified, cleanup the + # directory. + if os.stat (self.__time_stamp_file).st_mtime < cleanup_time: + os.utime (self.__time_stamp_file, (now, now)) + for file_name in os.listdir (self.__random_repository): + file_name = os.path.join (self.__random_repository, file_name) + if os.stat (file_name).st_mtime < cleanup_time: + os.unlink (file_name) + + # loop until a valid random string has been found and registered. + while True: + # generate a new random string. + random = self.__random_string () + + # open a file with the corresponding name in the repository + # directory in such a way, that the creation fails, when the + # file already exists. That should be near to impossible with + # good seeding of the random number generator, but it's better + # to play safe. + try: + os.close (os.open (os.path.join (self.__random_repository, + random), + os.O_EXCL | os.O_CREAT, 0700)) + except EnvironmentError, error: + # if the file already existed, rerun the loop to try the + # next string. + if error.errno == errno.EEXIST: + continue + else: + # other errors will certainly persist for other random + # strings, so raise the exception. + raise + + # return the successfully registered random string. + self.__random = random + return random + + def image_url (self, random = None, base = 'http://image.captchas.net/'): + if not random: + random = self.__random + url = base + url += '?client=%s&random=%s' % (self.__client, random) + if self.__alphabet != "abcdefghijklmnopqrstuvwxyz": + url += '&alphabet=%s' % self.__alphabet + if self.__letters != 6: + url += '&letters=%s' % self.__letters + if self.__width != 240: + url += '&width=%s' % self.__width + if self.__height != 80: + url += '&height=%s' % self.__height + return url + + def audio_url (self, random = None, base = 'http://audio.captchas.net/'): + if not random: + random = self.__random + url = base + url += '?client=%s&random=%s' % (self.__client, random) + if self.__alphabet != "abcdefghijklmnopqrstuvwxyz": + url += '&alphabet=%s' % self.__alphabet + if self.__letters != 6: + url += '&letters=%s' % self.__letters + return url + + def image (self, random = None, id = 'captchas.net'): + return ''' + The CAPTCHA image + ''' % (id, self.image_url (random), self.__width, self.__height, id, id) + + def validate (self, random): + self.__random = random + + file_name = os.path.join (self.__random_repository, random) + + # Find out, whether the file exists + result = os.path.isfile (file_name) + + # if the file exists, remember it. + if result: + self.__random_file = file_name + + # the random string was valid, if and only if the + # corresponding file existed. + return result + + def verify (self, input, random = None): + if not random: + random = self.__random + + # The format of the password. + password_alphabet = self.__alphabet + password_length = self.__letters + + # If the user input has the wrong lenght, it can't be correct. + if len (input) != password_length: + return False + + # Calculate the MD5 digest of the concatenation of secret key and + # random string. + encryption_base = self.__secret + random + if (password_alphabet != "abcdefghijklmnopqrstuvwxyz") or (password_length != 6): + encryption_base += ":" + password_alphabet + ":" + str(password_length) + digest = md5.new (encryption_base).digest () + + # Compute password + correct_password = '' + for pos in range (password_length): + letter_num = ord (digest[pos]) % len (password_alphabet) + correct_password += password_alphabet[letter_num] + + # Check password + if input != correct_password: + return False + + # Remove the correspondig random file, if it exists. + try: + os.unlink (self.__random_file) + del self.__random_file + except: + pass + + # The user input was correct. + return True Property changes on: tracspamfilter/captcha/captchasdotnet.py ___________________________________________________________________ Name: svn:eol-style + native Index: tracspamfilter/fonts/vera.ttf =================================================================== Cannot display: file marked as a binary type. svn:mime-type = application/octet-stream Property changes on: tracspamfilter/fonts/vera.ttf ___________________________________________________________________ Name: svn:mime-type + application/octet-stream Index: tracspamfilter/templates/verify_captcha.cs =================================================================== --- tracspamfilter/templates/verify_captcha.cs (revision 0) +++ tracspamfilter/templates/verify_captcha.cs (revision 0) @@ -0,0 +1,23 @@ + + + + +
+

Captcha Error

+

+ +
+ +
+

+Trac thinks your submission might be Spam. To prove otherwise please provide a response to the following. +

+

+ +

+Response: + +
+
+ + Index: setup.py =================================================================== --- setup.py (revision 4114) +++ setup.py (working copy) @@ -31,6 +31,7 @@ extras_require = { 'DNS': ['dnspython>=1.3.5'], 'SpamBayes': ['spambayes'], + 'PIL': ['pil'], }, entry_points = """ [trac.plugins] @@ -44,6 +45,10 @@ spamfilter.ip_throttle = tracspamfilter.filters.ip_throttle spamfilter.regex = tracspamfilter.filters.regex spamfilter.session = tracspamfilter.filters.session + spamfilter.captcha = tracspamfilter.captcha.api + spamfilter.captcha.image = tracspamfilter.captcha.image[PIL] + spamfilter.captcha.expression = tracspamfilter.captcha.expression + spamfilter.captcha.captchasdotnet = tracspamfilter.captcha.captchasdotnet """, test_suite = 'tracspamfilter.tests.suite', zip_safe = True