mirror of https://github.com/barberd/depace.git
141 lines
3.4 KiB
Python
Executable File
141 lines
3.4 KiB
Python
Executable File
#!/usr/bin/env python3
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import sys
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ror = lambda val, r_bits, max_bits: \
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((val & (2**max_bits-1)) >> r_bits%max_bits) | \
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(val << (max_bits-(r_bits%max_bits)) & (2**max_bits-1))
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rol = lambda val, r_bits, max_bits: \
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(val << r_bits%max_bits) & (2**max_bits-1) | \
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((val & (2**max_bits-1)) >> (max_bits-(r_bits%max_bits)))
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def getkey1(start,end):
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key = int("0x50414345",0)
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i = start + 0x80
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while(i<=(end + 0x80)):
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fh.seek(i);
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ib = int.from_bytes(fh.read(1),byteorder='big')
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key+=ib
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i+=1
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return key
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def get_bit(i):
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i=i%8
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return (0x1 << i)
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def getkey2(key,start,end,inflag,obfuscator):
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i = start
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while(i<=end):
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bitnum = 0x80
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if inflag==0:
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bitnum=0x1
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fh.seek(i+0x80);
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ib = int.from_bytes(fh.read(1),byteorder='big')
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while True:
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key = key << 1
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test_mask=get_bit(bitnum)
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if key<(2**32):
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if((test_mask & ib)==0):
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key = key ^ obfuscator
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else:
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key = key & 0xFFFFFFFF
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if((test_mask & ib)!=0):
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key = key ^ obfuscator
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if (inflag!=0):
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bitnum = ror(bitnum,1,8)
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if ((bitnum & 0x80)!=0):
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break
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else:
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bitnum = rol(bitnum,1,8)
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if ((bitnum & 0x1)==0x1):
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break
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i+=1
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return key
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def write_decrypt1(start,end,key):
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fh.seek(start+0x80)
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inblock=bytearray(fh.read(end-start+1))
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outblock=decrypt1(key,inblock[:])
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fh.seek(start+0x80)
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fh.write(bytes(outblock))
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def decrypt1(key,block):
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def rotate_key(d0,d1,d2):
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if d2==0:
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d0 = ror(d0,d1,32)
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else:
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d0 = rol(d0,d1,32)
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return d0
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i=0
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while i<len(block):
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key_lb = key&0xFF
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i_lb = i&0xFF
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if (i_lb&0x1 == 0):
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key_lb = key_lb & 0xF
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else:
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key_lb = (key_lb >> 4) &0xFFFF
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key = rotate_key(key,key_lb,0)
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ib = block[i]
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key_lb = key&0xFF
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output = ib ^ key_lb
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block[i]=output
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i+=1
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return block
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def write_decrypt2(i,end,key,salt):
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fh.seek(i+0x80)
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block=fh.read(end-i+1)
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fh.seek(i+0x80)
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fh.write(decrypt2(block,key,salt))
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def swap(inbyte):
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in_th = inbyte>>16
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in_bh = (inbyte & 0xFFFF)
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out = (in_bh << 16) + in_th
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return out
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def decrypt2(block,key,salt):
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blockarray=bytearray(block)
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i=0
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while(i<len(blockarray)):
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d2=key
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d4=key
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d2=swap(d2)
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key+=d2
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key=key & 0xFFFF
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d4=swap(d4)
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d4=d4 & 0xFFFF0000
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key+=d4
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key=swap(key)
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key+=salt
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key=key&0xFFFFFFFF
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ib = blockarray[i]
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output=ib ^ (key & 0xFF)
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blockarray[i]=output
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i+=1
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return bytes(blockarray)
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def copybytes(source,target,count):
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fh.seek(source+0x80)
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block=fh.read(count)
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fh.seek(target+0x80)
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fh.write(block)
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def savebytes(filename,start,end):
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fh.seek(start+0x80)
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oh=open(filename,"wb")
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oh.write(fh.read(end-start+1))
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oh.close()
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fh = open("StarTrek.bin","r+b")
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key= 0x9ad33b77 #0x1d448
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write_decrypt2(0x1d498,0x1d498+0x8fe-1,key,0x5a6b7c8d) #0x1d456
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fh.close()
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