能力值：
( LV9，RANK：170 )
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27 楼
再逆一个函数
这个函数是计算一个unicode 字串的checksum,有两个问题：
一，数组中第８行从80到90是不是写错了，漏写了0x ?
如果真是漏写了，那这个数组也没必要了，直接 v1 = b就行了，可能是有意这么写。
二，一个特别的数组，以乘以３７方式得到一个checksum，再以乘３１方式得到一个checksum，
这种算法，是某种标准，还是作者随意写出来的？我还不知道
typedef unsigned char BYTE;
typedef int BOOL;
BOOL __stdcall sub_12410(PCWSTR a0, OUT int* a4_checksum, OUT int* a8_checksum)
{
static const BYTE byte_28000[256] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
96, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,123,124,125,126,127, // 是不是写错了？漏写了 0x ?
128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,
160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,
176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,
192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,
208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,
224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,
240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,
};
int v18 = 0, v8 = 0;
if (a0 == NULL || a4_checksum == 0 || a8_checksum == 0)
return false;
ULONG v14 = wcslen(a0) * 2;
for (ULONG i=0; i < v14; i++)
{
BYTE b = ((BYTE*)a0)[i];
BYTE v1 = byte_28000; // 为什么不直接 v1 = b 呢
v18 = v18 * 37 + v1;
v8 = v8 * 31 + v1;
}
*a4_checksum = v18;
*a8_checksum = v8;
return true;
}
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