python解释NTFS runlist的代码
#!/usr/bin/python3#http://www.frombyte.com 张宇
import os
import sys
import random
import hashlib
import struct
import zlib
import re
def help_exit():
print("命令格式:")
print("python3 %s <File name> <Start bytes> <Start LCN> <Start VCN>:" % sys.argv)
print(" File name:要解释的包含runlist的文件名称")
print(" Start bytes:文件中要解释runlist的起始位置")
print(" Start LCN:runlist开始的参考LCN值，如果是一段完整的runlist，这个值应为0.")
print(" Start VCN:runlist开始的参考VCN值，如果是一段没有0x20的runlist，这个值多数为0.")
print(" *返回值：一个二维队列，打印结果。\n")
exit()
#通过抛出异常判断第一个参数是否是A-F
def is_num_by_except(s):
try:
a=int(s,16)
if (a>0 and a<=16): return True
else: return False
except ValueError:
return False
if len(sys.argv)!= 5 :
print("***参数数量或格式错误!")
help_exit()
if sys.argv.isdigit():
spoi = int(sys.argv)
if spoi<0:
print("***错误，起始字节位置不能取负值")
help_exit()
else:
print("***错误，起始字节位置应为非负整数")
help_exit()
if sys.argv.isdigit():
slcn = int(sys.argv)
if slcn<0:
print("***错误，起始LCN不能取负值")
help_exit()
else:
print("***错误，起始LCN应为非负整数")
help_exit()
if sys.argv.isdigit():
svcn = int(sys.argv)
if svcn<0:
print("***错误，起始VCN不能取负值")
help_exit()
else:
print("***错误，起始VCN应为非负整数")
help_exit()
def get_i(vl,ilen):
q=0
for i in range(0,ilen):
q = q | ( vl << i*8 )
#若为负数
if vl > 0x80:
q = q - (1 << ilen*8 )
return q
f = open("%s"%sys.argv,'rb')
f.seek(spoi)
data = f.read(1024)
v1 = 1
i = 0
lists = [ ]
del lists
while True:
t = struct.unpack_from('B',data,i)
v1 = t
if v1 == 0:
break
v1_p = (v1 & 0xF0) >> 4
v1_l = (v1 &0xF)
if (v1_l >=8) or (v1_p >=8) or (v1_l == 0):
print("***偏移%d:run list长度和位置字节有错误!***"%(i+spoi))
break
i = i+1
if (i+8) >= 1024:
break
t = struct.unpack_from('8s',data,i)
v1_dl = get_i(t,v1_l)
if v1_dl < 0:
print("***偏移%d:run片断长度不能为负!***"%(i+spoi))
break
i = i+ v1_l
if (i+8) >= 1024:
break
t = struct.unpack_from('8s',data,i)
v1_dp = get_i(t,v1_p)
slcn = slcn + v1_dp
lists.append()
i = i + v1_p
#print("%x,%x:%x,%x"%(v1_l,v1_p,v1_dl,slcn))
print("Runlist(共%d个片断):"%len(lists))
print("%20s%20s%20s"%("VCN","LCN","LEN"))
for i in lists:
print("%20d%20d%20d"%(svcn,i,i))
svcn += i
f.close()
页:
[1]