Initial checking of what was revision 56 on http://luks.endorphin.org/svn/cryptsetup

git-svn-id: https://cryptsetup.googlecode.com/svn/trunk@3 36d66b0a-2a48-0410-832c-cd162a569da5

luks/testing/fileDiffer.py

@@ -0,0 +1,129 @@
+#!/usr/bin/python
+
+#
+# Usage: fileDiffer <afile> <bfile> <list of disk changes>
+# 
+
+# LUKS 
+# quick regression test suite
+# Tests LUKS images for changes at certain disk offsets
+#
+# Does fast python code has to look ugly or is it just me?
+
+import sys
+
+class changes:
+	pass
+
+def parseArgs(args):
+	aFileName = args[1]
+	bFileName = args[2]
+	changelist = []
+	args[0:3] = []
+	for i in args:
+		mychanges = changes();
+		if i.startswith('A'):
+			mychanges.mode = 'ALLOWED'
+		if i.startswith('R'):
+			mychanges.mode = 'REQUIRED'
+			mychanges.strictness = 'RANDOM'
+		if i.startswith('S'):
+			mychanges.mode = 'REQUIRED'
+			mychanges.strictness = 'SEMANTIC'
+		
+		dashIndex = i.find('-')
+		if dashIndex == -1:			
+			mychanges.starts = int(i[1:])
+			mychanges.ends = mychanges.starts
+		else:
+			mychanges.starts = int(i[1:dashIndex])
+			mychanges.ends = int(i[dashIndex+1:])
+		mychanges.miss = 0
+		changelist.append(mychanges)
+	mychanges = changes();
+	mychanges.starts = 0
+#	mychanges.ends will be fixed later
+	mychanges.mode = 'FORBIDDEN'	
+	changelist.append(mychanges)
+	return [aFileName, bFileName, changelist]
+
+def mode(i):
+	for c in changelist:
+		if i >= c.starts and i<=c.ends:
+			return c
+def cleanchanges(i):
+	newchangelist=[]	
+	for c in changelist:
+		if i <= c.starts or i <= c.ends:
+			newchangelist.append(c)
+	return newchangelist
+
+[aFileName, bFileName, changelist] = parseArgs(sys.argv)
+
+aFile = open(aFileName,'r')
+bFile = open(bFileName,'r')
+
+aString = aFile.read()
+bString = bFile.read()
+
+if len(aString) != len(bString): 
+	sys.exit("Mismatch different file sizes")
+
+fileLen = len(aString)
+fileLen10th = fileLen/10
+
+# Create a catch all entry
+changelist[-1].ends = fileLen
+
+print "Changes list: (FORBIDDEN default)"
+print "start\tend\tmode\t\tstrictness"
+for i in changelist:
+	if i.mode == 'REQUIRED':
+		print "%d\t%d\t%s\t%s" % (i.starts, i.ends, i.mode, i.strictness)
+	else:
+		print "%d\t%d\t%s" % (i.starts, i.ends, i.mode)
+
+
+filepos = 0
+fileLen10thC = 0
+print "[..........]"
+sys.stdout.write("[")
+sys.stdout.flush()
+
+modeNotTrivial = 1
+while filepos < fileLen:
+
+	if modeNotTrivial == 1:
+		c = mode(filepos)
+#	print (filepos, c.mode)
+	if c.mode == 'REQUIRED':
+		if aString[filepos] == bString[filepos]:
+			c.miss = c.miss + 1
+	else:
+		if aString[filepos] != bString[filepos] and c.mode != 'ALLOWED':
+			sys.exit("Mismatch at %d: change forbidden" % filepos)
+
+	# Do some maintaince, print progress bar, and clean changelist
+	#
+	# Maintaining two counters appears to be faster than modulo operation
+	if fileLen10thC == fileLen10th:
+		fileLen10thC = 0
+		sys.stdout.write(".")
+		sys.stdout.flush()
+		changelist = cleanchanges(filepos)
+		if len(changelist) == 1:
+			modeNotTrivial = 0
+	filepos = filepos + 1
+	fileLen10thC = fileLen10thC + 1
+
+for c in changelist:
+	if c.mode == 'REQUIRED':
+		if c.strictness == 'SEMANTIC' and c.miss == (c.ends-c.starts+1):
+			sys.exit("Mismatch: not even a single change in region %d-%d." % (c.starts, c.ends))
+   	        # This is not correct. We should do a statistical test
+	        # of the sampled data against the hypothetical distribution
+	        # of collision. Chi-Square Test.
+		if c.strictness == 'RANDOM' and c.miss == (c.ends-c.starts+1):
+			sys.exit("Mismatch: not even a single change in region %d-%d." % (c.starts, c.ends))
+
+print ".] - everything ok"