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Tuts 4 You

[KeyGenMe] - AMD_64 crackme #1


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A very basic crackme I coded a few days ago, the purpose is to get yourself acquainted with the x64 intrinsics. Rules are basic too just fully reverse the damn thing and the first 2 people will get the crackmes source code.



Happy Reversing :)



EDIT: The second attachment contains the crackme with the MSVC libraries linked statically.


Available Sources For GiveAway: 1


Exodia and Kao solved this little toy



Edited by xSRTsect
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Ok, let me be the first to pass you the happy news :)


name: ChOoKi
code: BA3E066679EEname: Tuts4You
code: AD233D7A06DE9C00


Keygen is ready but better let others try too


cheers :peace:

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#include <stdio.h>#include <cstring>void encrypt(void* data, size_t len){    unsigned char table[] = //quem e o maior? sou eu o dcoder!    {        0x71, 0xE7, 0x4E, 0x88, 0x21, 0x4A, 0x72, 0xE8,        0x45, 0x14, 0x57, 0x1B, 0xE0, 0x28, 0xAC, 0xDB,        0x56, 0x83, 0x62, 0xDC, 0xA4, 0x8C, 0xC9, 0xF7,        0x75, 0xE2, 0x4B, 0xC4, 0x9C, 0x68, 0x80, 0xDD,        0xEA, 0x19, 0x1C, 0x65, 0x0D, 0xBD, 0x0A, 0x37,        0x1D, 0xCA, 0x2E, 0x64, 0x24, 0x38, 0x74, 0xAB,        0x02, 0xF4, 0x95, 0x07, 0x7B, 0xC2, 0xC0, 0xFB,        0x7F, 0x8B, 0xDA, 0x63, 0xAA, 0xD1, 0x55, 0x31,        0x66, 0x39, 0xDF, 0xAD, 0x08, 0x36, 0x01, 0x1E,        0x4C, 0xBB, 0x7A, 0x81, 0x8E, 0x58, 0xBC, 0xF3,        0x29, 0x76, 0xA5, 0xB0, 0x69, 0x43, 0xD7, 0xF1,        0x6C, 0x6B, 0x5C, 0xFE, 0x09, 0x4F, 0x46, 0xA2,        0xFD, 0xC7, 0x9A, 0xC3, 0x5B, 0x8A, 0xBF, 0x32,        0x5F, 0xDE, 0x53, 0x7D, 0xC1, 0x79, 0x96, 0xE9,        0xF9, 0x77, 0xA1, 0x2A, 0x0B, 0x87, 0x5E, 0xF8,        0x13, 0xC5, 0x51, 0xFF, 0x1F, 0xE4, 0x04, 0x92,        0x9D, 0xD8, 0x67, 0x85, 0xD2, 0xD6, 0x8D, 0x7C,        0xB7, 0x40, 0xB1, 0xB4, 0x9F, 0x3A, 0x60, 0x0E,        0x97, 0x98, 0xA7, 0x61, 0xCC, 0x99, 0xD9, 0x20,        0x78, 0x4D, 0x03, 0xF5, 0x7E, 0xA0, 0x94, 0xEB,        0xC8, 0x06, 0xBA, 0xE5, 0xAF, 0x50, 0x86, 0x27,        0x2D, 0xE6, 0xBE, 0xCB, 0x16, 0x11, 0xD5, 0x18,        0xA9, 0xF6, 0x41, 0xF2, 0xF0, 0x59, 0x9B, 0x2B,        0x0F, 0x15, 0xCF, 0x2C, 0x3C, 0x6F, 0xCD, 0x0C,        0x34, 0x82, 0x30, 0x6D, 0x8F, 0x9E, 0x35, 0xD3,        0x47, 0x23, 0xEF, 0xCE, 0xFC, 0xFA, 0xE3, 0xED,        0x05, 0x52, 0xA3, 0xA8, 0x3D, 0x25, 0x22, 0xB6,        0x17, 0xD0, 0xB9, 0x5D, 0x00, 0xA6, 0x3B, 0x54,        0xAE, 0x93, 0x26, 0xD4, 0xB5, 0x44, 0xEE, 0x89,        0x73, 0x48, 0x6E, 0x91, 0x10, 0x12, 0x3F, 0x84,        0x33, 0x2F, 0xB3, 0x70, 0x6A, 0x5A, 0xB2, 0x49,        0x90, 0xEC, 0xB8, 0x42, 0x3E, 0xE1, 0xC6, 0x1A    };    int storage = 0;    for(size_t i = 0; i < len; i++)    {        storage = (table[i + 1] + storage) & 0xFF;        //redundant swaps?        int x = table[i + 1];        table[i + 1] = table[storage];        table[storage] = x;        int xorval = table[(table[i + 1] + table[storage]) % 256];        ((unsigned char*)data)[i] ^= xorval;    }}int main(){    //unit test    unsigned char serial[] = {0x01, 0x23, 0x45, 0x67, 0x88, 0x9A, 0xBC, 0xDE, 0xF0, 0x12, 0x34, 0x56, 0x78};    encrypt(serial, sizeof(serial));    unsigned char cmp[]= {0xF8, 0x75, 0x0C, 0x6E, 0xBA, 0x1D, 0x4F, 0xAB, 0x87, 0x02, 0x1E, 0x23, 0x05};    if(!memcmp(cmp, serial, 0xd))        puts("all tests passed!\n");    //generate serial    printf("name: ");    char name[256]="";    fgets(name, sizeof(name), stdin);    int len=strlen(name);    name[len-- - 1]=0;    encrypt(name, len);    printf("code: ");    for(int i = 0; i < len; i++)        printf("%02X", (unsigned char)name[i]);    puts("");    return 0;}
EDIT: ChOoKi, first as always :D Edited by Mr. eXoDia
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