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一
逻辑分析
总结
1、前端为c#编写，如果输入的id和code满足条件就调用dll中的CheckCode进行判断，并且程序存在反调试功能。
2、dll中的CheckCode先将输入进行加密，之后和某32字节的数据进行比较。
二
动态调试
反调试
三
外层逻辑判断
array=[7,90,115,1,117,99,114,97,24]id=arraycode=list(b'))baa!!!(@@###qq')for i in range(len(code)):id[i%9]=code[i]^id[i%9]idstr=''for i in range(9):idstr+=chr(id[i])print(idstr)
四
CheckCode逻辑
for(int i=0;i<32;i++){keyexpantion(key)AES_CBC(code,key,iv)iv=SubBytes(iv)key^=ivkey=SbuBytes(key)iv^=key}
最后比较用的字节。
五
exp
from Crypto.Cipher import AESsbox = [[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]]def SubBytes(state):return [sbox[i][j] for i,j in [(t>>4,t&0xf) for t in state]]def Bytesxor(data1,data2):data1=list(data1)data2=list(data2)res=[]for i in range(len(data1)):res.append(data1[i]^data2[i])return bytearray(res)key=bytearray(b'x29x23xBEx84xE1x6CxD6xAEx52x90x49xF1xF1xBBxE9xEB')iv=bytearray(b'xB3xA6xDBx3Cx87x0Cx3Ex99x24x5Ex0Dx1Cx06xB7x47xDE')keyarray=[]keyarray.append(key)ivarray=[]ivarray.append(iv)data=b'xF6x1CxE3xD7xF9xFBx0Bx1Ax8BxA2x1DxD8x97x94x05xC4x6Dx97xE7x62xB6x7CxEFx9Ax88x1BxA4x4DxFDxB0xE4x6E'for i in range(31):iv=bytearray(SubBytes(iv))key=Bytesxor(key, iv)key=bytearray(SubBytes(key))keyarray.append(key)iv=Bytesxor(key, iv)ivarray.append(iv)keyarray.reverse()ivarray.reverse()print(len(keyarray))for i in range(32):key=keyarray[i]iv=ivarray[i]aes=AES.new(bytes(key), AES.MODE_CBC,bytes(iv))data=aes.decrypt(data)print(data)'''iv=subbytes(iv)key=key^ivkey=subbytes(key)iv^=key''''''key29 23 BE 84 E1 6C D6 AE 52 90 49 F1 F1 BB E9 EB1B C5 C5 A8 42 4F 43 09 43 E8 0B 3C 0B C9 3B 4226 27 03 37 AE 17 98 5E 1D 76 5D 86 52 D4 15 5D20 56 F3 DF E4 A7 7E E5 70 68 69 D5 70 F7 F9 C9'''
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