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[原创]第六题 一尺之棰
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2020-4-26 20:25 4591
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题目分析
1. 程序接收输入将其转换为数值，要求输入长度64，输入字符为0-9，A-F
2. 保存当前输入长度到输出的起始两个字节
3. 逐字节的将输入转化（转化过程见代码）为一定长度的bits
4. 处理完输入后再额外处理5个字节，数值为current_len & 1
5. 把输出当输入重复步骤2 16次
6. 要求输出和内置的数组相等
解题思路
1. 输出数组的头两个字节为上一次输入的长度
2. 输入长度之后的一定长度的bit仅和输入的第一个字节有关
3. 之后bit都和当前输入字节以及之前的输入有关
因此可以逐字节的爆破出输入，重复16次后得到注册码，此方法简单无脑，就是效率低
解题代码
计算时要注意设置舍入控制位域为向上，同时注意double和int间的类型转换和数值复制的区别
最终结果为：504964774D526B756F467A705C4D654B7645587746634A7A75505F757A75776C
#include <vector>
#include <xmmintrin.h>
using namespace std;
typedef struct {
vector<unsigned int> ary;
double v12;
double v13;
vector<unsigned char> buf;
int v15;
int v18;
int v14;
vector<unsigned char> results;
} statu;
void init_statu(statu& s)
{
for (int i = 0; i < 257; i++)
s.ary.push_back(i);
s.buf.assign(0x2000, 0);
s.results.assign(0x2000, 0);
s.v12 = 0.0;
s.v13 = 1.0;
s.v15 = 0;
s.v18 = 2;
s.v14 = 2;
}
statu next_(unsigned char a, statu s, int n, int m)
{
uint64_t ary64[257] = { 0 };
double v24 = (s.v13 - s.v12) / (double)(s.ary[256]);
double double_value = 0;
double* tmp = &double_value;
for (int i = 0; i < 257; i++)
{
*tmp = v24 * (double)s.ary[i] + s.v12;
ary64[i] = ((*(uint64_t*)tmp & 0x7FFFFFFC00i64 | (((char)*(uint64_t*)tmp & 7 | ((*(uint64_t*)tmp & 0xFFFFFFFFFFFFFFF8ui64) << 30)) << 6)) << 18) | ((*(uint64_t*)tmp & 0x10000000000000i64 | (((*(uint64_t*)tmp >> 1) ^ (*(uint64_t*)tmp ^ (*(uint64_t*)tmp >> 1)) & 0xFFF8000000000ui64) >> 14)) >> 25);
}
uint64_t value = ary64[a];
*(uint64_t*)tmp = ((value & 0x8000000 | ((value & 0x1FFF | (2 * (value & 0xFFFFFFFFFFFFE000ui64))) << 14)) << 25) | ((value & 0x1FFFFFFF0000000i64 | (((value >> 30) ^ (value ^ (value >> 30)) & 0x7000000) >> 6)) >> 18);
s.v12 = *tmp;
value = ary64[a + 1];
*(uint64_t*)tmp = ((value & 0x8000000 | ((value & 0x1FFF | (2 * (value & 0xFFFFFFFFFFFFE000ui64))) << 14)) << 25) | ((value & 0x1FFFFFFF0000000i64 | (((value >> 30) ^ (value ^ (value >> 30)) & 0x7000000) >> 6)) >> 18);
s.v13 = *tmp;
int buf_index = s.v15;
int v34 = 0;
int v40 = (int)(s.v12 * 2.0);
int v41 = (int)(s.v13 * 2.0);
while (v40 == v41)
{
s.buf[buf_index] = (char)v40;
buf_index++;
v34++;
s.v13 = (s.v13 * 2.0) - v41;
v41 = (int)(s.v13 * 2.0);
s.v12 = (s.v12 * 2.0) - v40;
v40 = (int)(s.v12 * 2.0);
if (v34 >= 0x1000)
{
*(int16_t*)&s.results[0] = 0;
return s;
}
}
int v43 = 0;
int v44 = v34 + s.v15;
int v45 = v44 / 8;
s.v15 = v44 % 8;
if (v44 / 8 > 0)
{
buf_index = 0;
v43 = ((v44 & 7) + v44) >> 3;
int v47 = v45;
s.v18 += v45;
while (v47)
{
--v47;
unsigned char foo = 0;
for (int i = 0, j = 7; i < 8; i++, j--)
foo |= (s.buf[buf_index + i] << j);
buf_index += 8;
s.results[s.v14] = foo;
++s.v14;
}
}
memmove(&s.buf[0], &s.buf[8 * v45], s.v15);
for (int i = a + 1; i < 257; i++)
{
if (i > 0)
s.ary[i] += (a % (n + 16)) + (n + 16);
}
return s;
}
vector<unsigned char> g_input;
int find(statu s, unsigned char* results, int results_len, int n, int16_t m)
{
if (m > *(int16_t*)results + 5)
return 0;
int range = 0x100;
int i = 0;
if (m > *(int16_t*)results)
{
i = (m - 1) & 1;
range = i + 1;
}
for (; i < range; i++)
{
unsigned char next_input = i;
statu tmp = next_(next_input, s, n, m);
if (tmp.v14 > results_len)
continue;
if (!memcmp(&tmp.results[0], results, tmp.v14))
{
if (tmp.v15 ==0)
{
if (m == *(int16_t*)results + 5 && tmp.v14 == results_len)
{
g_input.insert(g_input.begin(), next_input);
return 1;
}
}
else
{
unsigned char foo = 0;
int p = 0, q = 7;
for (; p < tmp.v15; p++, q--)
foo |= (tmp.buf[p] << q);
if (m == *(int16_t*)results + 5 && tmp.v14 == results_len - 1)
{
if (foo == results[results_len - 1])
{
g_input.insert(g_input.begin(), next_input);
return 1;
}
}
unsigned char a1 = foo;
unsigned char a2 = results[tmp.v14];
while (a1 != 0)
{
if (a1 & 1)
{
if ((a1 & 1) != (a2 & 1))
break;
}
a1 = a1 >> 1;
a2 = a2 >> 1;
}
if (a1)
continue;
}
if (find(tmp, results, results_len, n, m + 1))
{
g_input.insert(g_input.begin(), next_input);
return 1;
}
}
else
{
continue;
}
}
return 0;
}
char test_input[0x1000] = { 0x11, 0x11, 0x11, 0x11, 0x22, 0x22, 0x22, 0x22, 0x33, 0x33, 0x33, 0x33, 0x44, 0x44, 0x44, 0x44, 0x55, 0x55, 0x55, 0x55, 0x66, 0x66, 0x66, 0x66, 0x77, 0x77, 0x77, 0x77, 0x88, 0x88, 0x88, 0x88 };
int main()
{
_mm_setcsr(0x5f80);//设置舍入控制位域
unsigned char results[0x1000] = { 0x05, 0x03, 0x82, 0x01, 0xE0, 0xFF, 0xB0, 0xAB, 0xCB, 0x8B, 0xB1, 0x99, 0xCA, 0x1A, 0xC1, 0x57, 0x9A, 0xA7, 0xB1, 0xDA, 0xE5, 0xD5, 0x2E, 0x89, 0x65, 0x70, 0x58, 0x70, 0xA4, 0x5F, 0x6D, 0xBC, 0x44, 0x57, 0xED, 0x48, 0x03, 0xA5, 0x1B, 0xAF, 0x04, 0x28, 0xF8, 0x38, 0x34, 0xC8, 0x9C, 0xAB, 0x6A, 0x16, 0x44, 0x7B, 0x65, 0x62, 0x93, 0x03, 0x21, 0x22, 0x12, 0xCF, 0x7D, 0x0C, 0x18, 0x12, 0xF6, 0x2D, 0x06, 0x81, 0xF3, 0x62, 0x72, 0x6F, 0xB0, 0x5B, 0xA2, 0x9E, 0x13, 0xE9, 0x7D, 0xB3, 0xCA, 0x5A, 0x9F, 0x00, 0xAC, 0xD2, 0xFF, 0xA5, 0x69, 0xD6, 0xC7, 0xED, 0x53, 0x76, 0x8A, 0xFE, 0x19, 0xFF, 0x3C, 0xE9, 0x63, 0x01, 0x66, 0x1B, 0x32, 0xAD, 0xF4, 0x94, 0x4E, 0x68, 0xFF, 0x55, 0x80, 0xF3, 0xD3, 0xDB, 0xB3, 0xC2, 0xCA, 0xF9, 0xA2, 0x5D, 0xCE, 0x12, 0xBD, 0x3C, 0x14, 0x93, 0xF9, 0x88, 0xEE, 0x40, 0x35, 0xF9, 0x16, 0x1C, 0x9F, 0x76, 0xF8, 0x0C, 0x7E, 0xF0, 0xB7, 0x02, 0x5B, 0x89, 0x26, 0xB6, 0xD6, 0x4C, 0xCA, 0xB2, 0x34, 0xD9, 0x8F, 0x6E, 0xFB, 0xF2, 0x52, 0x38, 0x21, 0x84, 0x37, 0xE7, 0x79, 0xF0, 0x4E, 0x09, 0x8C, 0xEC, 0x19, 0xDC, 0x08, 0x1A, 0xF9, 0xFA, 0xAD, 0x02, 0x74, 0x3B, 0x2B, 0x21, 0xCC, 0xD2, 0xBD, 0xAD, 0xB0, 0xB8, 0x56, 0x92, 0x10, 0x4B, 0x3D, 0x12, 0xA5, 0x4D, 0xF9, 0x87, 0xE5, 0x20, 0xEA, 0xE1, 0xD9, 0x5C, 0x7C, 0x5F, 0xB9, 0x25, 0x40, 0xA4, 0xCE, 0x8E, 0xFB, 0x94, 0x79, 0x47, 0xBF, 0x99, 0xBC, 0x17, 0xDC, 0x4C, 0xAD, 0xAB, 0xA6, 0x9C, 0x76, 0xBF, 0xB3, 0x12, 0x60, 0x26, 0xB1, 0x54, 0x1A, 0x41, 0x23, 0xCA, 0x10, 0xB3, 0xBC, 0x36, 0x04, 0x86, 0x27, 0x0D, 0xC2, 0x9C, 0xE1, 0x3C, 0x47, 0x94, 0x11, 0x18, 0x48, 0xC0, 0x88, 0xCA, 0x17, 0xC9, 0xAA, 0x69, 0xA1, 0xEC, 0x2D, 0x88, 0xD8, 0x67, 0x86, 0x90, 0xF0, 0x89, 0xF1, 0x64, 0xA9, 0xE2, 0x5D, 0xB1, 0xAA, 0x70, 0x75, 0xAF, 0x7D, 0x53, 0x30, 0x2D, 0xD9, 0x90, 0xED, 0x28, 0xC5, 0x2C, 0x04, 0x7D, 0x56, 0xDC, 0xBA, 0xDA, 0x09, 0xE2, 0xF0, 0xFF, 0xAF, 0x8F, 0xFF, 0xCE, 0x52, 0xBB, 0xC3, 0xDD, 0x68, 0x23, 0x38, 0xB3, 0x9E, 0x73, 0xCF, 0x68, 0xBD, 0x4B, 0x6B, 0xBB, 0xC6, 0x09, 0xEA, 0x01, 0xB8, 0xF9, 0x15, 0x25, 0x8E, 0x23, 0xE1, 0xC9, 0x60, 0x27, 0xBE, 0x03, 0x24, 0x0F, 0x2F, 0x23, 0xBF, 0x28, 0x0E, 0x60, 0x90, 0x34, 0x7B, 0x34, 0xA8, 0xBB, 0x0F, 0x0C, 0x3C, 0xF3, 0xD9, 0xE4, 0x2C, 0xC9, 0x42, 0xB5, 0x92, 0x6C, 0x70, 0x81, 0x55, 0x6B, 0x0F, 0x27, 0xB9, 0x1F, 0xF7, 0x78, 0x95, 0x4F, 0x69, 0x47, 0x81, 0x2F, 0x99, 0x6E, 0x75, 0x62, 0x5A, 0x78, 0xCA, 0x4C, 0x6C, 0x77, 0x52, 0x48, 0x48, 0xC1, 0x62, 0x6A, 0x4A, 0x90, 0xFB, 0x11, 0x16, 0x97, 0xF2, 0x7F, 0x29, 0xCF, 0x9D, 0xD1, 0x21, 0xB1, 0x3B, 0xD2, 0x60, 0xA7, 0x54, 0xB5, 0x5F, 0x2E, 0x11, 0xBA, 0x5A, 0x6C, 0x7F, 0xC9, 0xB5, 0xA0, 0x2A, 0xE9, 0xD1, 0x15, 0x03, 0x55, 0x4D, 0x88, 0x79, 0xF3, 0xDE, 0xC6, 0xCF, 0x45, 0x7E, 0x43, 0x25, 0x18, 0x21, 0x7E, 0xDE, 0x64, 0x39, 0x20, 0x1A, 0x77, 0x8C, 0x32, 0xAD, 0xB7, 0xE3, 0x1C, 0x32, 0x4C, 0x38, 0x4C, 0xAE, 0x82, 0xD8, 0x08, 0x85, 0x31, 0xA4, 0x1A, 0x40, 0x17, 0x22, 0xAE, 0x57, 0x0D, 0x8C, 0x81, 0x4A, 0x31, 0x60, 0x87, 0xAC, 0x15, 0xFF, 0x74, 0x04, 0xC8, 0xA4, 0xE4, 0x3A, 0x90, 0x0E, 0x40, 0xDE, 0x37, 0xF6, 0x65, 0x93, 0xA7, 0x89, 0xCC, 0xC2, 0x53, 0x58, 0x4E, 0xEB, 0x5A, 0x1B, 0x43, 0x82, 0x03, 0x3B, 0x00, 0xCF, 0x6F, 0x04, 0x3E, 0x38, 0x2A, 0x60, 0x0D, 0x9D, 0xC1, 0x1E, 0x38, 0x05, 0x8D, 0x12, 0x01, 0x33, 0x15, 0x15, 0x20, 0x9D, 0xA4, 0x21, 0xC1, 0x86, 0xB8, 0xEE, 0x6C, 0x9F, 0x32, 0x12, 0x52, 0x4C, 0xED, 0xE5, 0x0E, 0xDD, 0xA7, 0x6A, 0xDB, 0x4D, 0xF3, 0x65, 0xB3, 0x78, 0x2E, 0x19, 0x4B, 0x72, 0xA0, 0x14, 0x68, 0xDE, 0xCD, 0xA2, 0xE0, 0x6A, 0xFE, 0x99, 0x12, 0xAA, 0x1C, 0x5F, 0x4E, 0x7B, 0x94, 0xAD, 0x99, 0x06, 0xA3, 0x23, 0xB5, 0x86, 0x4E, 0x35, 0xC1, 0x7D, 0xA1, 0x7B, 0xF6, 0x5B, 0x78, 0x8D, 0x62, 0xB9, 0x9E, 0x17, 0x68, 0x7D, 0x21, 0x80, 0xFF, 0xFA, 0xC9, 0xC6, 0xB0, 0x91, 0xA7, 0x54, 0x0B, 0xB9, 0x0C, 0xA6, 0xF3, 0xC4, 0x23, 0xBD, 0x39, 0xF8, 0x44, 0x65, 0x46, 0xAC, 0xB0, 0x03, 0xD4, 0xEE, 0x40, 0x20, 0xBA, 0x10, 0x56, 0xF2, 0x99, 0x27, 0x9F, 0x55, 0x3B, 0x92, 0xF1, 0x89, 0x5B, 0xAF, 0x77, 0x53, 0x54, 0x15, 0xD3, 0x45, 0x41, 0x11, 0xD8, 0x70, 0xB0, 0xAC, 0xC5, 0x5C, 0x22, 0xF3, 0xF0, 0x85, 0x1E, 0x51, 0x01, 0x0B, 0x7E, 0x65, 0x9D, 0x1F, 0xD1, 0x29, 0xAD, 0xFE, 0x6B, 0x0E, 0xB3, 0xC3, 0x19, 0xC3, 0x49, 0x24, 0x45, 0xB1, 0x04, 0x4F, 0xAB, 0xDC, 0xC8, 0xA5, 0xD6, 0x28, 0x02, 0x53, 0xE6, 0xB5, 0x5E, 0xA6, 0x93, 0x8C, 0x02, 0xCF, 0x79, 0x8A, 0x46, 0x4B, 0x14, 0x77, 0x3C, 0x20, 0x60, 0xF6, 0x9E, 0xAC, 0xFF, 0x74, 0x37, 0x90, 0x86, 0xE3, 0xD8, 0x9C, 0xA1, 0x63, 0xFF, 0x69, 0xBD, 0x8C, 0x5A, 0x2A, 0xA9, 0x1E, 0x8B, 0xA5, 0x36, 0xA6, 0xA1, 0xBC, 0x38, 0x05, 0xD1, 0xAA, 0x86, 0x29, 0x9F, 0x23, 0x7D, 0x58, 0xDF, 0x78, 0x08, 0x81, 0x2A, 0x05, 0xD6, 0x77, 0xD5, 0x90, 0x4E, 0xB4, 0x45, 0xC5, 0xE7, 0xCC, 0x75, 0xCC, 0x7D, 0x4B, 0xC2, 0x60, 0x4D, 0xF7, 0xF0, 0xC6, 0x53, 0x51, 0x79, 0xA6, 0xEA, 0x52, 0xC2, 0xA1, 0xA7, 0x80, 0x0C, 0x7A, 0x72, 0x76, 0xCA, 0x08, 0x8D, 0xDC, 0x3C, 0x21, 0xCA, 0xA0, 0x9C, 0x2A, 0xC3, 0xFD, 0x7A, 0x1D, 0xE6, 0xFC, 0xFD, 0x16, 0x27, 0x1C, 0xBC, 0x87, 0x91, 0xB5, 0xB9, 0xE1, 0xBB, 0xE9, 0x3F, 0xCA, 0x13, 0x2C, 0xE1, 0x82, 0x86, 0x33, 0xB3, 0xC2, 0xBF, 0x10, 0xC5, 0xC2, 0x56, 0xF4, 0xFE, 0x86, 0xB8, 0x3D, 0x19, 0xEB, 0x55, 0xAE, 0xCE, 0x7E, 0x29, 0x7E, 0xE4, 0xD8, 0xE6, 0x28, 0xBA, 0x00, 0xBE, 0xE4, 0xB6, 0x65, 0x81, 0x2E, 0xFA, 0x49, 0x36, 0x74, 0x79, 0x5B, 0xBB, 0x7F, 0x46, 0xA6, 0x61, 0xD9, 0xDF, 0x2E, 0xDD, 0xF7, 0x55, 0x02, 0x65, 0xA7, 0xF8, 0x55, 0x4E, 0x69, 0x65, 0xEB, 0xFC, 0xB3, 0xDC, 0x92, 0x62, 0x79, 0x1E, 0xE0, 0xCF, 0x3B, 0xD5, 0xAB, 0x8A, 0x5C, 0x93, 0x14, 0x8E, 0x21, 0xC4, 0x98, 0xEA };
int results_len = 0x38A;
statu s;
init_statu(s);
for (int n = 15; n >= 0; n--)
{
statu s;
init_statu(s);
memcpy(&s.results[0], results, 2);
::find(s, results, results_len, n, 1);
for (int i = 0; i < g_input.size(); i++)
{
printf("%.02x ", g_input[i]);
}
printf("\n%d -----------------------------\n", n);
if (g_input.size() == 0)
break;
results_len = g_input.size() -5;
memcpy(results, &g_input[0], results_len);
g_input.clear();
}
return 0;
}
[培训]《安卓高级研修班(网课)》月薪三万计划，掌握调试、分析还原ollvm、vmp的方法，定制art虚拟机自动化脱壳的方法
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