def fingerprint(self):
"""Select num_probes most useful paths, and fetch them
from the site at url. Return an ordered list of possible versions or
[].
"""
self._load_db()
paths = wafu.pick_fingerprint_files(self.path_nodes, self.all_versions)
self.logger.logStartFingerprint(self.url, self.app_name)
self.error_page_fingerprint = wafu.identify_error_page(self.url)
possible_vers = []
for path in paths[:self.num_probes]:
curr_vers = self.fingerprint_file(path)
if curr_vers:
possible_vers.append(curr_vers)
if self._host_down_errors >= HOST_DOWN_THRESHOLD:
break
ver_set = wafu.collapse_version_possibilities(possible_vers)
self.ver_list = list(ver_set)
#if more than one possibility, try to narrow it by winnowing!
if len(self.ver_list) > 1 and self.winnow:
print "ver_list before winnowing:"
for v in self.ver_list:
print v.vstring
print "\n"
self.winnow_versions(possible_vers)
ver_set = wafu.collapse_version_possibilities(possible_vers)
self.ver_list = list(ver_set)
self.ver_list.sort()
if len(self.ver_list) > 1:
self.best_guess = wafu.pick_likely_version(self.ver_list)
elif len(self.ver_list) == 1:
self.best_guess = self.ver_list[0]
else:
self.best_guess = None
self.logger.logFinishFingerprint(self.ver_list, self.best_guess)
return self.ver_list
def winnow_versions(self, possible_vers):
winnow_attempts = 0
while len(self.ver_list) > 1 and winnow_attempts < self.num_probes:
winnow_paths = wafu.pick_winnow_files(self.ver_list, self.version_nodes, self.num_probes - winnow_attempts)
if not winnow_paths:
break
for path in winnow_paths:
winnow_attempts += 1
curr_vers = self.fingerprint_file(path)
if curr_vers:
possible_vers.append(curr_vers)
tmp_ver_set = wafu.collapse_version_possibilities(possible_vers)
#if winnowing knocked out a possibility, repick winnow files base on this new info
if len(tmp_ver_set) < len(self.ver_list):
self.ver_list = list(tmp_ver_set)
print "winnow eliminated a version... repicking"
continue
if self._host_down_errors >= HOST_DOWN_THRESHOLD:
break
if winnow_attempts > self.num_probes:
break
