2022DASCTFxSU三月春季赛login wp

这题好像是 re 的那道 0 解题,赛后自己拿到附件做了一下

大致分析

  • 题目给了两个附件 loginchecklogin 相当于客户端而 check 相当于服务端进行校验
  • 程序是静态编译的去除了符号信息,为了方便后续分析可以使用 ida 插件 Finger识别库函数(结果不一定准确,需要看一下函数内容)
  • logincheck 两个进程通过 socket 进行通信,下面列出一些 socket 通信的函数的声明及作用
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int socket(int domain, int type, int protocol);		
//create an endpoint for communication

int listen(int sockfd, int backlog);
//listen for connections on a socket

int connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen);
//initiate a connection on a socket

int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen);
//accept jobs sent to a destination

int bind(int sockfd, const struct sockaddr *addr, socklen_t addrlen);
//bind a name to a socket

ssize_t send(int sockfd, const void *buf, size_t len, int flags);
ssize_t recv(int sockfd, void *buf, size_t len, int flags);

ssize_t sendto(int sockfd, const void *buf, size_t len, int flags,
const struct sockaddr *dest_addr, socklen_t addrlen);
ssize_t recvfrom(int sockfd, void *buf, size_t len, int flags,
struct sockaddr *src_addr, socklen_t *addrlen);

int close(int fd);
  • recvfrom 接收到输入的 tokenpassword,只有在 tokenpassword 都校验通过的时候才会 check flag

check Token

  • gmpz 是一个大数计算库,这里可以看出进行了 c^e%n 的运算(就是 RSA),如果没有识别函数这里也可以通过数字 0x10001 和 大数猜测出是 RSA
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void mpz_powm (mpz_ptr r, mpz_srcptr b, mpz_srcptr e, mpz_srcptr m);
/*mpz_powm(res,base,exp,mod) -- Set R to (U^E) mod M.*/

int mpz_init_set_str (mpz_ptr x, const char *str, int base);
/*mpz_init_set_str(string, base) -- Convert the \0-terminated string STRING in
base BASE to a multiple precision integer. Allow white space in the string.
If BASE == 0 determine the base in the C standard way, i.e. 0xhh...h means
base 16, 0oo...o means base 8, otherwise assume base 10.*/

int mpz_cmp (mpz_srcptr u, mpz_srcptr v)
/*mpz_cmp(u,v) -- Compare U, V. Return positive, zero, or negative
based on if U > V, U == V, or U < V.*/
  • Rsatools 解一下

check Password

  • 一个矩阵运算,通过 sage 求解,random 得到的值可以自己写一个跑出结果(没有 srand
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#BX=A
B=Matrix(Zmod(257),[[113,219,37,46,122,15],[76,163,106,34,170,41],[110,27,169,122,138,39],[47,128,240,14,170,86],[247,89,88,0,169,242],[246,154,78,28,72,201]])

A=Matrix(Zmod(257),[[0xa3, 0x97, 0xa2, 0x55, 0x53, 0xbe],[0xf1, 0xfc, 0xf9, 0x79, 0x6b, 0x52], [0x14, 0x13, 0xe9, 0xe2, 0x2d, 0x51], [0x8e, 0x1f, 0x56, 0x8, 0x57, 0x27], [0xa7, 0x5, 0xd4, 0xd0, 0x52, 0x82], [0x77, 0x75, 0x1b, 0x99, 0x4a,0xed]])

pwd=B.solve_right(A)
'''
[ 81 50 210 2 195 45]
[149 185 249 120 213 20]
[227 41 66 32 81 59]
[ 21 98 52 130 180 192]
[ 46 154 253 232 186 213]
[236 7 72 106 84 136]
'''
for i in pwd:
for j in i:
print("%02x" %j)

check Flag

  • 可以明显看出通过 tokenpassword 检查后的第一个 recvfrom 获取的值不是最后输入 flag,转而分析 login,在 login

发现发送了一串 16 进制字符串,可以看出是 AES 加密的逆盒

  • 正确的 tokenpwd 重新组合作为 AES 加密的 key,这里的 AES 是魔改过的所以还需要继续分析
  • 与标准的 AES 进行对照,发现多了个 xor 操作还有把 sub_bytes 替换成了 inv_sub_bytes
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/*
* Addition in GF(2^8)
* http://en.wikipedia.org/wiki/Finite_field_arithmetic
*/
uint8_t gadd(uint8_t a, uint8_t b)
{
return a ^ b;
}

/*
* Subtraction in GF(2^8)
* http://en.wikipedia.org/wiki/Finite_field_arithmetic
*/
uint8_t gsub(uint8_t a, uint8_t b)
{
return a ^ b;
}

/*
* Multiplication in GF(2^8)
* http://en.wikipedia.org/wiki/Finite_field_arithmetic
* Irreducible polynomial m(x) = x8 + x4 + x3 + x + 1
*
* NOTE: This function can be easily replaced with a look up table for a speed
* boost, at the expense of an increase in memory size (around 65 KB). See
* the aes.h header file to find the macro definition.
uint8_t gmult(uint8_t a, uint8_t b) {

uint8_t p = 0, i = 0, hbs = 0;

for (i = 0; i < 8; i++) {
if (b & 1) {
p ^= a;
}

hbs = a & 0x80;
a <<= 1;
if (hbs) a ^= 0x1b; // 0000 0001 0001 1011
b >>= 1;
}

return (uint8_t)p;
}
*/

/*
* Addition of 4 byte words
* m(x) = x4+1
*/
void coef_add(uint8_t a[], uint8_t b[], uint8_t d[])
{

d[0] = a[0] ^ b[0];
d[1] = a[1] ^ b[1];
d[2] = a[2] ^ b[2];
d[3] = a[3] ^ b[3];
}

/*
* Multiplication of 4 byte words
* m(x) = x4+1
*/
void coef_mult(uint8_t *a, uint8_t *b, uint8_t *d)
{

d[0] = gmult(a[0], b[0]) ^ gmult(a[3], b[1]) ^ gmult(a[2], b[2]) ^ gmult(a[1], b[3]);
d[1] = gmult(a[1], b[0]) ^ gmult(a[0], b[1]) ^ gmult(a[3], b[2]) ^ gmult(a[2], b[3]);
d[2] = gmult(a[2], b[0]) ^ gmult(a[1], b[1]) ^ gmult(a[0], b[2]) ^ gmult(a[3], b[3]);
d[3] = gmult(a[3], b[0]) ^ gmult(a[2], b[1]) ^ gmult(a[1], b[2]) ^ gmult(a[0], b[3]);
}

/*
* The cipher Key.
*/
int K;

/*
* Number of columns (32-bit words) comprising the State. For this
* standard, Nb = 4.
*/
const int Nb = 4;

/*
* Number of 32-bit words comprising the Cipher Key. For this
* standard, Nk = 4, 6, or 8.
*/
int Nk;

/*
* Number of rounds, which is a function of Nk and Nb (which is
* fixed). For this standard, Nr = 10, 12, or 14.
*/
int Nr;

/*
* S-box transformation table
*/
static uint8_t s_box[256] = {
// 0 1 2 3 4 5 6 7 8 9 a b c d e f
0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01,
0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76, 0xCA, 0x82, 0xC9, 0x7D,
0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4,
0x72, 0xC0, 0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC,
0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15, 0x04, 0xC7,
0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2,
0xEB, 0x27, 0xB2, 0x75, 0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E,
0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84,
0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB,
0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF, 0xD0, 0xEF, 0xAA, 0xFB,
0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C,
0x9F, 0xA8, 0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5,
0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2, 0xCD, 0x0C,
0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D,
0x64, 0x5D, 0x19, 0x73, 0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A,
0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB,
0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3,
0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, 0xE7, 0xC8, 0x37, 0x6D,
0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A,
0xAE, 0x08, 0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6,
0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A, 0x70, 0x3E,
0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9,
0x86, 0xC1, 0x1D, 0x9E, 0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9,
0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99,
0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16}; // f

/*
* Inverse S-box transformation table
*/
static uint8_t inv_s_box[256] = {
// 0 1 2 3 4 5 6 7 8 9 a b c d e f
0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40,
0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB, 0x7C, 0xE3, 0x39, 0x82,
0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE,
0xE9, 0xCB, 0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D,
0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E, 0x08, 0x2E,
0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49,
0x6D, 0x8B, 0xD1, 0x25, 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68,
0x98, 0x16, 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92,
0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15,
0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84, 0x90, 0xD8, 0xAB, 0x00,
0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3,
0x45, 0x06, 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02,
0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, 0x3A, 0x91,
0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE,
0xF0, 0xB4, 0xE6, 0x73, 0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD,
0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E,
0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 0x6F, 0xB7,
0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, 0xFC, 0x56, 0x3E, 0x4B,
0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD,
0x5A, 0xF4, 0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31,
0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F, 0x60, 0x51,
0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 0x2D, 0xE5, 0x7A, 0x9F,
0x93, 0xC9, 0x9C, 0xEF, 0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A,
0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61,
0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69,
0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D}; // f

/*
* Generates the round constant Rcon[i]
*/
uint8_t R[] = {0x02, 0x00, 0x00, 0x00};

uint8_t *Rcon(uint8_t i)
{

if (i == 1)
{
R[0] = 0x01; // x^(1-1) = x^0 = 1
}
else if (i > 1)
{
R[0] = 0x02;
i--;
while (i > 1)
{
R[0] = gmult(R[0], 0x02);
i--;
}
}

return R;
}

/*
* Transformation in the Cipher and Inverse Cipher in which a Round
* Key is added to the State using an XOR operation. The length of a
* Round Key equals the size of the State (i.e., for Nb = 4, the Round
* Key length equals 128 bits/16 bytes).
*/
void add_round_key(uint8_t *state, uint8_t *w, uint8_t r)
{

uint8_t i;

for (i = 0; i < Nb; i++)
{
for (uint8_t j = 0; j <= 3; j++)
{
state[4 * i + j] ^= w[4 * j + i];
}
}
}

/*
* Transformation in the Cipher that takes all of the columns of the
* State and mixes their data (independently of one another) to
* produce new columns.
*/
char unknow(uint8_t *w, char state, char matrix)
{
char result; // al
char v4; // al
char v5; // al
char v6; // al
char v7; // al
char v8; // al
char v9; // bl
char v10; // al
char v11; // al
char v12; // al
char v13; // al
char v14; // [rsp+1Fh] [rbp-11h]

if ( state >= 0 )
result = 2 * state;
else
result = (2 * state) ^ 0x1B;
v14 = result;
if ( matrix == 1 )
return state;
if ( matrix != 2 )
{
switch ( matrix )
{
case 3:
result ^= state;
break;
case 4:
result = unknow(w, result, 2);
break;
case 8:
v4 = unknow(w, result, 2);
result = unknow(w, v4, 2);
break;
case 9:
v5 = unknow(w, result, 2);
result = state ^ unknow(w, v5, 2);
break;
case 10:
v6 = unknow(w, result, 2);
result = v14 ^ unknow(w, v6, 2);
break;
case 11:
v7 = unknow(w, result, 2);
result = state ^ v14 ^ unknow(w, v7, 2);
break;
case 12:
v8 = unknow(w, result, 2);
v9 = unknow(w, v8, 2);
result = v9 ^ unknow(w, v14, 2);
break;
case 13:
v10 = unknow(w, result, 2);
v11 = unknow(w, v10, 2);
result = state ^ v11 ^ unknow(w, v14, 2);
break;
default:
v12 = unknow(w, result, 2);
v13 = unknow(w, v12, 2);
result = v14 ^ v13 ^ unknow(w, v14, 2);
break;
}
}
return result;
}

void mix_columns(uint8_t *w, uint8_t *state)
{

uint8_t a[] = {0x02, 0x01, 0x01, 0x03}; // a(x) = {02} + {01}x + {01}x2 + {03}x3
uint8_t i, j, col[4], res[4];

for (j = 0; j < Nb; j++) {
for (i = 0; i < 4; i++) {
col[i] = state[Nb*i+j];
}

coef_mult(a, col, res);

for (i = 0; i < 4; i++) {
state[Nb*i+j] = res[i];
}
}
}

/*
* Transformation in the Inverse Cipher that is the inverse of
* MixColumns().
*/
void inv_mix_columns(uint8_t *w ,uint8_t *state)
{

uint8_t a[] = {0x0e, 0x09, 0x0d, 0x0b}; // a(x) = {0e} + {09}x + {0d}x2 + {0b}x3
uint8_t i, j, col[4], res[4];

for (j = 0; j < Nb; j++) {
for (i = 0; i < 4; i++) {
col[i] = state[Nb*i+j];
}

coef_mult(a, col, res);

for (i = 0; i < 4; i++) {
state[Nb*i+j] = res[i];
}
}
}

/*
* Transformation in the Cipher that processes the State by cyclically
* shifting the last three rows of the State by different offsets.
*/
void shift_rows(uint8_t *state)
{

uint8_t i, k, s, tmp;

for (i = 1; i < 4; i++)
{
s = 0;
while (1)
{
uint8_t v2 = s++;
if (!(i > v2))
{
break;
}
tmp = state[Nb * i + 0];

for (k = 1; k < Nb; k++)
{
state[Nb * i + k - 1] = state[Nb * i + k];
}

state[Nb * i + Nb - 1] = tmp;
}
}
}

/*
* Transformation in the Inverse Cipher that is the inverse of
* ShiftRows().
*/
void inv_shift_rows(uint8_t *state)
{

uint8_t i, k, s, tmp;

for (i = 1; i < 4; i++)
{
s = 0;
while (s < i)
{
tmp = state[Nb * i + Nb - 1];

for (k = Nb - 1; k > 0; k--)
{
state[Nb * i + k] = state[Nb * i + k - 1];
}

state[Nb * i + 0] = tmp;
s++;
}
}
}

/*
* Transformation in the Cipher that processes the State using a non­
* linear byte substitution table (S-box) that operates on each of the
* State bytes independently.
*/
void sub_bytes(uint8_t *state)
{

uint8_t i, j;

for (i = 0; i < 4; i++)
{
for (j = 0; j < Nb; j++)
{
state[Nb * i + j] = s_box[state[Nb * i + j]];
}
}
}

/*
* Transformation in the Inverse Cipher that is the inverse of
* SubBytes().
*/
void inv_sub_bytes(uint8_t *state)
{

uint8_t i, j;

for (i = 0; i < 4; i++)
{
for (j = 0; j < Nb; j++)
{
state[Nb * i + j] = inv_s_box[state[Nb * i + j]];
}
}
}

/*
* Function used in the Key Expansion routine that takes a four-byte
* input word and applies an S-box to each of the four bytes to
* produce an output word.
*/
void sub_word(uint8_t *w)
{

uint8_t i;

for (i = 0; i < 4; i++)
{
w[i] = s_box[w[i]];
}
}

/*
* Function used in the Key Expansion routine that takes a four-byte
* word and performs a cyclic permutation.
*/
void rot_word(uint8_t *w)
{

uint8_t tmp;
uint8_t i;

tmp = w[0];

for (i = 0; i < 3; i++)
{
w[i] = w[i + 1];
}

w[3] = tmp;
}

/*
* Key Expansion
*/
void aes_key_expansion(uint8_t *key, uint8_t *w)
{

uint8_t tmp[4];
uint8_t i;
uint8_t len = Nb * (Nr + 1);
uint8_t RCON[] = {0x8d, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0};

for (i = 0; i < Nk; i++)
{
w[4 * i + 0] = key[4 * i + 0];
w[4 * i + 1] = key[4 * i + 1];
w[4 * i + 2] = key[4 * i + 2];
w[4 * i + 3] = key[4 * i + 3];
}

for (i = Nk; i < len; i++)
{
tmp[0] = w[4 * (i - 1) + 0];
tmp[1] = w[4 * (i - 1) + 1];
tmp[2] = w[4 * (i - 1) + 2];
tmp[3] = w[4 * (i - 1) + 3];

if ((i & 3) == 0)
{
tmp[1] = s_box[tmp[2]];
tmp[2] = s_box[tmp[3]];
tmp[3] = s_box[w[4 * (i - 1)]];
tmp[0] = s_box[w[4 * (i - 1) + 1]] ^ RCON[i >> 2];
}

w[4 * i + 0] = w[4 * (i - Nk) + 0] ^ tmp[0];
w[4 * i + 1] = w[4 * (i - Nk) + 1] ^ tmp[1];
w[4 * i + 2] = w[4 * (i - Nk) + 2] ^ tmp[2];
w[4 * i + 3] = w[4 * (i - Nk) + 3] ^ tmp[3];
}
}

/*
* Initialize AES variables and allocate memory for expanded key
*/
uint8_t *aes_init(unsigned key_size)
{

switch (key_size)
{
default:
case 16:
Nk = 4;
Nr = 10;
break;
case 24:
Nk = 6;
Nr = 12;
break;
case 32:
Nk = 8;
Nr = 14;
break;
}

return malloc(Nb * (Nr + 1) * 4);
}

/*
* Performs the AES cipher operation
*/
void xor (char *in, char *key)
{
for (int i = 0; i <= 15; ++i)
{
in[i] ^= key[i];
}
}
/*
* Performs the AES cipher operation
*/
void aes_cipher(uint8_t *w, uint8_t *in, uint8_t *out, uint8_t *key)
{

uint8_t state[4 * 4]={0};
uint8_t r, i, j;

xor(in, key);
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
{
state[4 * j + i] = in[4*i + j];
}
}

add_round_key(state, w, 0);

for (r = 1;; r++)
{
inv_sub_bytes(state);
shift_rows(state);
if (r == 10)
break;
mix_columns(w, state);
add_round_key(state, w+16*r, 0);
}

add_round_key(state, w+160, 0);

for (i = 0; i < 4; i++)
{
for (j = 0; j < Nb; j++)
{
out[i + 4 * j] = state[Nb * i + j];
}
}

for(int i=0;i<30;i+=2)
{
sprintf(out+i,"%02x",state[(i*2)%15]);
}
sprintf(out+30,"%02x",state[15]);
}

/*
* Performs the AES inverse cipher operation
*/
void aes_inv_cipher(uint8_t* w,uint8_t *in, uint8_t *out, uint8_t *key)
{
// uint8_t Te_InvS[16][16] = { 0 }; //逆S盒缓存
// uint8_t Te_InVSAdd[2] = { 0 }; //位置
// for (uint8_t i = 0; i < 16; i++) { //计算逆S盒
// for (uint8_t n = 0; n < 16; n++) {
// Te_InVSAdd[0] = (s_box[i*16+n] >> 4) & 0x0f; //取⾏
// Te_InVSAdd[1] = (s_box[i*16+n] >> 0) & 0x0f; //取列
// Te_InvS[Te_InVSAdd[0]][Te_InVSAdd[1]] = i * 16 + n; //置值
// }
// }
uint8_t state[4 * 4]={0};
uint8_t r, i, j;

for (i = 0; i < 4; i++)
{
for (j = 0; j < Nb; j++)
{
state[Nb * i + j] = in[i + 4 * j];
}
}

add_round_key(state, w+160, 0);

for (r = Nr - 1; r >= 1; r--)
{
inv_shift_rows(state);
sub_bytes(state);
add_round_key(state, w+16*r, 0);
inv_mix_columns(w,state);
}

inv_shift_rows(state);
sub_bytes(state);
add_round_key(state, w, 0);

for (i = 0; i < 4; i++)
{
for (j = 0; j < Nb; j++)
{
out[i + 4 * j] = state[Nb * i + j];
}
}

xor(out, key);
}

int main()
{

uint8_t i;

/* 256 bit key */
uint8_t key[] = {0x32, 0x30, 0x07, 0x36, 0x6A, 0x37, 0x78, 0x31, 0x48, 0x39,
0x42, 0x39, 0x14, 0x31, 0xD5, 0x32, 0x62, 0x36, 0xF9, 0x38,
0x42, 0x30, 0xC3, 0x31, 0x6A, 0x35, 0x48, 0x38, 0x34, 0x35,
0x54, 0x34, 0x29, 0x34, 0x51, 0x36, 0x15, 0x39, 0xD2, 0x38,
0xD2, 0x39, 0x20, 0x31, 0xB9, 0x32, 0x2E, 0x30};


/*
uint8_t in[16] = {0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61};

unsigned char out[1000] =
"\xfe\xf9\xe7\x3e\xf6\xa1\x23\xcc\x57\x61\xc1\x15\x77\xfb\x9c\xbb\xca\x2f\xb1\xe8\x4f\xd9\x07\xd8\x0c\x6b\xea\xcf\xe8\x42\xa2\xfa";

uint8_t *w; // expanded key

w = aes_init(16);
memset(w, 0, 176);

aes_key_expansion(key, w);

for (int j = 0; j < 16; j += 0x10)
aes_cipher(w, (__int64)(&in[(j / 8) * 8]), (__int64)(&out[(j / 4) * 8]), (__int64)(&key[(j / 8 + 2) * 8]));

printf("%s",out);
printf("\n");

free(w);
system("pause");
*/

uint8_t *w;
uint8_t out[33] = {0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61, 0x61};
unsigned char in[] =
"\xfe\xf9\xe7\x3e\xf6\xa1\x23\xcc\x57\x61\xc1\x15\x77\xfb\x9c\xbb\xca\x2f\xb1\xe8\x4f\xd9\x07\xd8\x0c\x6b\xea\xcf\xe8\x42\xa2\xfa";

w = aes_init(16);
memset(w, 0, 176);

aes_key_expansion(key, w);
for (int j = 0; j <32 ; j += 0x10)
aes_inv_cipher(w, (__int64)(&in[j]), (__int64)(&out[j]), (__int64)(&key[(j / 8 + 2) * 8]));

printf("%s",out);
printf("\n");

free(w);
system("pause");

return 0;
}
  • 附看雪上 AES 标准加解密的流程图
作者

0wl

发布于

2022-04-02

更新于

2022-04-03

许可协议

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