ENH+BF: Capture multiline matched lines into fail ticket

Previously only the last line of the match was being saved, not all
lines involved in matching.

Log lines are now broken into 3 part tuple, with the line pre-datetime,
the datetime, and post-datetime. Allows reformation of full line, but
also use of the line without the datetime present.
Attempting to use the term "tupleLine(s)" where possible, to avoid
confusion with normal read lines.

May also wish to consider that regexs could be made to capture more
lines of interest if some form of unique reference is available. This
may allow more lines of interest to be captured, which may not be picked
up by the traditional "grep <ip>" approach i.e. ones which do not have
the ip address in.

This also simplified the fail2ban-regex statistics for missed lines.
Also resolved bug with missed lines time extracted for debuggex having
some lines present which were captured in a multiline regex.
Also resolved independent issue with ignored line check including the
datetime, which raised assertion error in the rare case the datetime
matched the ignore regex, and the rest of line only matched a failregex

bin/fail2ban-regex

@@ -309,7 +309,7 @@ class Fail2banRegex(object):
 	def testIgnoreRegex(self, line):
 		found = False
 		try:
-			ret = self._filter.ignoreLine(line)
+			ret = self._filter.ignoreLine([(line,"","")])
 			if ret is not None:
 				found = True
 				regex = self._ignoreregex[ret].inc()
@@ -338,35 +338,27 @@ class Fail2banRegex(object):
 			return False
 		for bufLine in orgLineBuffer[int(fullBuffer):]:
 			if bufLine not in self._filter._Filter__lineBuffer:
-				if self.removeMissedLine(bufLine):
+				try:
+					self._line_stats.missed_lines.pop(
+						self._line_stats.missed_lines.index("".join(bufLine)))
+					self._line_stats.missed_lines_timeextracted.pop(
+						self._line_stats.missed_lines_timeextracted.index(
+							"".join(bufLine[::2])))
+				except ValueError:
+					pass
+				else:
 					self._line_stats.matched += 1
 		return line, ret
 
-	def removeMissedLine(self, line):
-		"""Remove `line` from missed lines, by comparing without time match"""
-		for n, missed_line in \
-				enumerate(reversed(self._line_stats.missed_lines)):
-			timeMatch = self._filter.dateDetector.matchTime(
-				missed_line, incHits=False)
-			if timeMatch:
-				logLine = (missed_line[:timeMatch.start()] +
-					missed_line[timeMatch.end():])
-			else:
-				logLine = missed_line
-			if logLine.rstrip("\r\n") == line:
-				self._line_stats.missed_lines.pop(
-					len(self._line_stats.missed_lines) - n - 1)
-				return True
-		return False
-
 	def process(self, test_lines):
 
 		for line_no, line in enumerate(test_lines):
-			if line.startswith('#') or not line.strip():
+			line = line.strip('\r\n')
+			if line.startswith('#') or not line:
 				# skip comment and empty lines
 				continue
-			is_ignored = fail2banRegex.testIgnoreRegex(line)
 			line_datetimestripped, ret = fail2banRegex.testRegex(line)
+			is_ignored = fail2banRegex.testIgnoreRegex(line_datetimestripped)
 
 			if is_ignored:
 				self._line_stats.ignored_lines.append(line)

fail2ban/server/failregex.py

@@ -74,8 +74,9 @@ class Regex:
 	# method of this object.
 	# @param value the line
 	
-	def search(self, value):
-		self._matchCache = self._regexObj.search(value)
+	def search(self, tupleLines):
+		self._matchCache = self._regexObj.search(
+			"\n".join("".join(value[::2]) for value in tupleLines) + "\n")
 		if self.hasMatched():
 			# Find start of the first line where the match was found
 			try:
@@ -89,8 +90,26 @@ class Regex:
 					"\n", self._matchCache.end() - 1) + 1
 			except ValueError:
 				self._matchLineEnd = len(self._matchCache.string)
-	
-	##
+
+
+			lineCount1 = self._matchCache.string.count(
+				"\n", 0, self._matchLineStart)
+			lineCount2 = self._matchCache.string.count(
+				"\n", 0, self._matchLineEnd)
+			self._matchedTupleLines = tupleLines[lineCount1:lineCount2]
+			self._unmatchedTupleLines = tupleLines[:lineCount1]
+
+			n = 0
+			for skippedLine in self.getSkippedLines():
+				for m, matchedTupleLine in enumerate(
+					self._matchedTupleLines[n:]):
+					if "".join(matchedTupleLine[::2]) == skippedLine:
+						self._unmatchedTupleLines.append(
+							self._matchedTupleLines.pop(n+m))
+						n += m
+						break
+			self._unmatchedTupleLines.extend(tupleLines[lineCount2:])
+
 	# Checks if the previous call to search() matched.
 	#
 	# @return True if a match was found, False otherwise
@@ -125,15 +144,18 @@ class Regex:
 	#
 	# This returns unmatched lines including captured by the <SKIPLINES> tag.
 	# @return list of unmatched lines
-	
+
+	def getUnmatchedTupleLines(self):
+		if not self.hasMatched():
+			return []
+		else:
+			return self._unmatchedTupleLines
+
 	def getUnmatchedLines(self):
 		if not self.hasMatched():
 			return []
-		unmatchedLines = (
-			self._matchCache.string[:self._matchLineStart].splitlines(False)
-			+ self.getSkippedLines()
-			+ self._matchCache.string[self._matchLineEnd:].splitlines(False))
-		return unmatchedLines
+		else:
+			return ["".join(line) for line in self._unmatchedTupleLines]
 
 	##
 	# Returns matched lines.
@@ -141,14 +163,18 @@ class Regex:
 	# This returns matched lines by excluding those captured
 	# by the <SKIPLINES> tag.
 	# @return list of matched lines
-	
+
+	def getMatchedTupleLines(self):
+		if not self.hasMatched():
+			return []
+		else:
+			return self._matchedTupleLines
+
 	def getMatchedLines(self):
 		if not self.hasMatched():
 			return []
-		matchedLines = self._matchCache.string[
-			self._matchLineStart:self._matchLineEnd].splitlines(False)
-		return [line for line in matchedLines
-			if line not in self.getSkippedLines()]
+		else:
+			return ["".join(line) for line in self._matchedTupleLines]
 
 ##
 # Exception dedicated to the class Regex.

fail2ban/server/filter.py

@@ -366,17 +366,12 @@ class Filter(JailThread):
 
 		timeMatch = self.dateDetector.matchTime(l)
 		if timeMatch:
-			# Lets split into time part and log part of the line
-			timeText = timeMatch.group()
-			# Lets leave the beginning in as well, so if there is no
-			# anchore at the beginning of the time regexp, we don't
-			# at least allow injection. Should be harmless otherwise
-			logLine  = l[:timeMatch.start()] + l[timeMatch.end():]
+			tupleLine  = (l[:timeMatch.start()], l[timeMatch.start():timeMatch.end()] , l[timeMatch.end():])
 		else:
-			timeText = None
-			logLine = l
+			tupleLine = (l,"","")
 
-		return logLine, self.findFailure(timeText, logLine, returnRawHost, checkAllRegex)
+		return "".join(tupleLine[::2]), self.findFailure(
+			tupleLine, returnRawHost, checkAllRegex)
 
 	def processLineAndAdd(self, line):
 		"""Processes the line for failures and populates failManager
@@ -385,6 +380,7 @@ class Filter(JailThread):
 			failregex = element[0]
 			ip = element[1]
 			unixTime = element[2]
+			lines = element[3]
 			logSys.debug("Processing line with time:%s and ip:%s"
 						 % (unixTime, ip))
 			if unixTime < MyTime.time() - self.getFindTime():
@@ -396,7 +392,7 @@ class Filter(JailThread):
 				continue
 			logSys.debug("Found %s" % ip)
 			## print "D: Adding a ticket for %s" % ((ip, unixTime, [line]),)
-			self.failManager.addFailure(FailTicket(ip, unixTime, [line]))
+			self.failManager.addFailure(FailTicket(ip, unixTime, lines))
 
 	##
 	# Returns true if the line should be ignored.
@@ -405,9 +401,9 @@ class Filter(JailThread):
 	# @param line: the line
 	# @return: a boolean
 
-	def ignoreLine(self, line):
+	def ignoreLine(self, tupleLines):
 		for ignoreRegexIndex, ignoreRegex in enumerate(self.__ignoreRegex):
-			ignoreRegex.search(line)
+			ignoreRegex.search(tupleLines)
 			if ignoreRegex.hasMatched():
 				return ignoreRegexIndex
 		return None
@@ -419,17 +415,17 @@ class Filter(JailThread):
 	# to find the logging time.
 	# @return a dict with IP and timestamp.
 
-	def findFailure(self, timeText, logLine,
-			returnRawHost=False, checkAllRegex=False):
+	def findFailure(self, tupleLine, returnRawHost=False, checkAllRegex=False):
 		failList = list()
 
 		# Checks if we must ignore this line.
-		if self.ignoreLine(logLine) is not None:
+		if self.ignoreLine([tupleLine[::2]]) is not None:
 			# The ignoreregex matched. Return.
-			logSys.log(7, "Matched ignoreregex and was \"%s\" ignored", logLine)
+			logSys.log(7, "Matched ignoreregex and was \"%s\" ignored",
+				"".join(tupleLine[::2]))
 			return failList
 
-
+		timeText = tupleLine[1]
 		if timeText:
 
 			dateTimeMatch = self.dateDetector.getTime(timeText)
@@ -446,49 +442,53 @@ class Filter(JailThread):
 				self.__lastTimeText = timeText
 				self.__lastDate = date
 		else:
-			timeText = self.__lastTimeText or logLine
+			timeText = self.__lastTimeText or "".join(tupleLine[::2])
 			date = self.__lastDate
 
-		self.__lineBuffer = (self.__lineBuffer + [logLine])[-self.__lineBufferSize:]
-
-		logLine = "\n".join(self.__lineBuffer) + "\n"
+		self.__lineBuffer = (
+			self.__lineBuffer + [tupleLine])[-self.__lineBufferSize:]
 
 		# Iterates over all the regular expressions.
 		for failRegexIndex, failRegex in enumerate(self.__failRegex):
-			failRegex.search(logLine)
+			failRegex.search(self.__lineBuffer)
 			if failRegex.hasMatched():
+				# The failregex matched.
+				logSys.log(7, "Matched %s", failRegex)
 				# Checks if we must ignore this match.
-				if self.ignoreLine(
-						"\n".join(failRegex.getMatchedLines()) + "\n") \
+				if self.ignoreLine(failRegex.getMatchedTupleLines()) \
 						is not None:
 					# The ignoreregex matched. Remove ignored match.
-					self.__lineBuffer = failRegex.getUnmatchedLines()
+					self.__lineBuffer = failRegex.getUnmatchedTupleLines()
 					logSys.log(7, "Matched ignoreregex and was ignored")
-					continue
-				# The failregex matched.
-				logSys.log(7, "Matched %s", failRegex)
+					if not checkAllRegex:
+						break
+					else:
+						continue
 				if date is None:
-					logSys.debug("Found a match for %r but no valid date/time "
-								 "found for %r. Please try setting a custom "
-								 "date pattern (see man page jail.conf(5)). "
-								 "If format is complex, please "
-								 "file a detailed issue on"
-								 " https://github.com/fail2ban/fail2ban/issues "
-								 "in order to get support for this format."
-								 % (logLine, timeText))
+					logSys.debug(
+						"Found a match for %r but no valid date/time "
+						"found for %r. Please try setting a custom "
+						"date pattern (see man page jail.conf(5)). "
+						"If format is complex, please "
+						"file a detailed issue on"
+						" https://github.com/fail2ban/fail2ban/issues "
+						"in order to get support for this format."
+						 % ("\n".join(failRegex.getMatchedLines()), timeText))
 				else:
-					self.__lineBuffer = failRegex.getUnmatchedLines()
+					self.__lineBuffer = failRegex.getUnmatchedTupleLines()
 					try:
 						host = failRegex.getHost()
 						if returnRawHost:
-							failList.append([failRegexIndex, host, date])
+							failList.append([failRegexIndex, host, date,
+								 failRegex.getMatchedLines()])
 							if not checkAllRegex:
 								break
 						else:
 							ipMatch = DNSUtils.textToIp(host, self.__useDns)
 							if ipMatch:
 								for ip in ipMatch:
-									failList.append([failRegexIndex, ip, date])
+									failList.append([failRegexIndex, ip, date,
+										 failRegex.getMatchedLines()])
 								if not checkAllRegex:
 									break
 					except RegexException, e: # pragma: no cover - unsure if reachable

fail2ban/tests/filtertestcase.py

@@ -710,7 +710,7 @@ class GetFailures(unittest.TestCase):
 
 	# so that they could be reused by other tests
 	FAILURES_01 = ('193.168.0.128', 3, 1124017199.0,
-				  [u'Aug 14 11:59:59 [sshd] error: PAM: Authentication failure for kevin from 193.168.0.128\n']*3)
+				  [u'Aug 14 11:59:59 [sshd] error: PAM: Authentication failure for kevin from 193.168.0.128']*3)
 
 	def setUp(self):
 		"""Call before every test case."""
@@ -747,16 +747,13 @@ class GetFailures(unittest.TestCase):
 		fout.close()
 
 		# now see if we should be getting the "same" failures
-		self.testGetFailures01(filename=fname,
-							   failures=GetFailures.FAILURES_01[:3] +
-							   ([x.rstrip('\n') + '\r\n' for x in
-								 GetFailures.FAILURES_01[-1]],))
+		self.testGetFailures01(filename=fname)
 		_killfile(fout, fname)
 
 
 	def testGetFailures02(self):
 		output = ('141.3.81.106', 4, 1124017139.0,
-				  [u'Aug 14 11:%d:59 i60p295 sshd[12365]: Failed publickey for roehl from ::ffff:141.3.81.106 port 51332 ssh2\n'
+				  [u'Aug 14 11:%d:59 i60p295 sshd[12365]: Failed publickey for roehl from ::ffff:141.3.81.106 port 51332 ssh2'
 				   % m for m in 53, 54, 57, 58])
 
 		self.filter.addLogPath(GetFailures.FILENAME_02)
@@ -789,11 +786,11 @@ class GetFailures(unittest.TestCase):
 	def testGetFailuresUseDNS(self):
 		# We should still catch failures with usedns = no ;-)
 		output_yes = ('93.184.216.119', 2, 1124017139.0,
-					  [u'Aug 14 11:54:59 i60p295 sshd[12365]: Failed publickey for roehl from example.com port 51332 ssh2\n',
-					   u'Aug 14 11:58:59 i60p295 sshd[12365]: Failed publickey for roehl from ::ffff:93.184.216.119 port 51332 ssh2\n'])
+					  [u'Aug 14 11:54:59 i60p295 sshd[12365]: Failed publickey for roehl from example.com port 51332 ssh2',
+					   u'Aug 14 11:58:59 i60p295 sshd[12365]: Failed publickey for roehl from ::ffff:93.184.216.119 port 51332 ssh2'])
 
 		output_no = ('93.184.216.119', 1, 1124017139.0,
-					  [u'Aug 14 11:58:59 i60p295 sshd[12365]: Failed publickey for roehl from ::ffff:93.184.216.119 port 51332 ssh2\n'])
+					  [u'Aug 14 11:58:59 i60p295 sshd[12365]: Failed publickey for roehl from ::ffff:93.184.216.119 port 51332 ssh2'])
 
 		# Actually no exception would be raised -- it will be just set to 'no'
 		#self.assertRaises(ValueError,

fail2ban/tests/samplestestcase.py

@@ -119,7 +119,7 @@ def testSampleRegexsFactory(name):
 								 (map(lambda x: x[0], ret),logFile.filename(), logFile.filelineno()))
 
 				# Verify timestamp and host as expected
-				failregex, host, fail2banTime = ret[0]
+				failregex, host, fail2banTime, lines = ret[0]
 				self.assertEqual(host, faildata.get("host", None))
 
 				t = faildata.get("time", None)