ftpdecrypt.py

def decrypt(filepath):						
	print "[!] Starting decryption...."
	dec_filename = ANONYMOUS_FILEPATH + os.path.basename(filepath).strip(".enc")
	inFile = open(filepath,"r")				
	chunksize=64*1024						
	hash = inFile.read(32)					
	encAESKey = inFile.read(512)			
	
	private_key_loc = PRIV_KEY_LOC			
	privkey = open(private_key_loc, "r").read()			
	rsakey = RSA.importKey(privkey)
	rsakey = PKCS1_OAEP.new(rsakey)						
	aes_key = rsakey.decrypt(encAESKey) 				
	
	origsize = struct.unpack('<Q', inFile.read(struct.calcsize('Q')))[0]	
	iv = inFile.read(16)								
	decryptor = AES.new(aes_key, AES.MODE_CBC, iv)		

	with open(dec_filename, 'wb') as outfile:
		while True:
			chunk = inFile.read(chunksize)
			if len(chunk) == 0:
				break
			outfile.write(decryptor.decrypt(chunk))		
		
		outfile.truncate(origsize)						
	
	print "[+] File was decrypted and saved at \""+dec_filename+"\""
	
	print "[!] Validating integrity..."
	if (validateIntegrity(hash, dec_filename)):			
		print "[+] Integrity validation Passed!"
	else:
		print "[-] Integrity validation Failed!"
	
	return dec_filename