忘了这题叫啥了，但是文件名是app-debug 符号表都没删，容易看出是一个hill加密，拿python解密脚本跑一遍就行。
import numpy as np
import gmpy2
def decode(s: str, key: str):
ss = []
for i in s:
ss.append(ord(i.upper()) - 65)
keys = []
for i in range(len(s)):
keys.append([])
for j in range(len(s)):
keys[i].append(ord(key[i*len(s) + j].upper())-65)
keys = np.array(keys)
det = int(np.linalg.det(keys))
keys_inv = np.linalg.inv(keys)
keys_star = keys_inv * det
det_inv = int(gmpy2.invert(det, 26))
keys = (det_inv * keys_star) % 26
ss = np.array(ss)
ret = ''
for i in np.dot(keys, ss):
ret += chr(65 + int(i + 1e-6) % 26)
return ret
if __name__ == '__main__':
key = bytes([6, 0x18, 1, 0xD, 0x10, 0xA, 0x14, 0x11, 0xF]).decode()
s = 'BUZSXRMNAIJKNHIWAYRZNXCALWXHFMMNO'
ans = ''
for i in range(0, len(s), 3):
ans += decode(s[i : i + 3], key)
print(ans)跑出来后交了几遍都不对，问工作人员说没问题，给我自己整不会了。结果过了十五分钟突然通知说要算个md5，幸好手快还是把一血拿下了。
拿D810反混淆，容易看出是一个blowfish加密带rc4，但实际解出来发现不对，下断点测试发现blowfish没问题，rc4的sbox没问题，仔细观察后发现魔改了rc4加密的最后一步Data[k] ^= s[t]为Data[k] += s[t] + 16 - 0x178B1710;，改成Data[k] -= s[t] + 16 - 0x178B1710;解密就行。
#include <stdio.h>
#include <inttypes.h>
typedef struct
{
uint32_t P[16 + 2];
uint32_t S[4][256];
} BLOWFISH_CTX;
void Blowfish_Init(BLOWFISH_CTX* ctx, uint8_t* key, int32_t keyLen);
void Blowfish_Encrypt(BLOWFISH_CTX* ctx, uint32_t* xl, uint32_t* xr);
void Blowfish_Decrypt(BLOWFISH_CTX* ctx, uint32_t* xl, uint32_t* xr);
#define N 16
static const uint32_t ORIG_P[16 + 2] = {
0x243F6A88L, 0x85A308D3L, 0x13198A2EL, 0x03707344L,
0xA4093822L, 0x299F31D0L, 0x082EFA98L, 0xEC4E6C89L,
0x452821E6L, 0x38D01377L, 0xBE5466CFL, 0x34E90C6CL,
0xC0AC29B7L, 0xC97C50DDL, 0x3F84D5B5L, 0xB5470917L,
0x9216D5D9L, 0x8979FB1BL
};
static const uint32_t ORIG_S[4][256] = {
{ 0xD1310BA6L, 0x98DFB5ACL, 0x2FFD72DBL, 0xD01ADFB7L,
0xB8E1AFEDL, 0x6A267E96L, 0xBA7C9045L, 0xF12C7F99L,
0x24A19947L, 0xB3916CF7L, 0x0801F2E2L, 0x858EFC16L,
0x636920D8L, 0x71574E69L, 0xA458FEA3L, 0xF4933D7EL,
0x0D95748FL, 0x728EB658L, 0x718BCD58L, 0x82154AEEL,
0x7B54A41DL, 0xC25A59B5L, 0x9C30D539L, 0x2AF26013L,
0xC5D1B023L, 0x286085F0L, 0xCA417918L, 0xB8DB38EFL,
0x8E79DCB0L, 0x603A180EL, 0x6C9E0E8BL, 0xB01E8A3EL,
0xD71577C1L, 0xBD314B27L, 0x78AF2FDAL, 0x55605C60L,
0xE65525F3L, 0xAA55AB94L, 0x57489862L, 0x63E81440L,
0x55CA396AL, 0x2AAB10B6L, 0xB4CC5C34L, 0x1141E8CEL,
0xA15486AFL, 0x7C72E993L, 0xB3EE1411L, 0x636FBC2AL,
0x2BA9C55DL, 0x741831F6L, 0xCE5C3E16L, 0x9B87931EL,
0xAFD6BA33L, 0x6C24CF5CL, 0x7A325381L, 0x28958677L,
0x3B8F4898L, 0x6B4BB9AFL, 0xC4BFE81BL, 0x66282193L,
0x61D809CCL, 0xFB21A991L, 0x487CAC60L, 0x5DEC8032L,
0xEF845D5DL, 0xE98575B1L, 0xDC262302L, 0xEB651B88L,
0x23893E81L, 0xD396ACC5L, 0x0F6D6FF3L, 0x83F44239L,
0x2E0B4482L, 0xA4842004L, 0x69C8F04AL, 0x9E1F9B5EL,
0x21C66842L, 0xF6E96C9AL, 0x670C9C61L, 0xABD388F0L,
0x6A51A0D2L, 0xD8542F68L, 0x960FA728L, 0xAB5133A3L,
0x6EEF0B6CL, 0x137A3BE4L, 0xBA3BF050L, 0x7EFB2A98L,
0xA1F1651DL, 0x39AF0176L, 0x66CA593EL, 0x82430E88L,
0x8CEE8619L, 0x456F9FB4L, 0x7D84A5C3L, 0x3B8B5EBEL,
0xE06F75D8L, 0x85C12073L, 0x401A449FL, 0x56C16AA6L,
0x4ED3AA62L, 0x363F7706L, 0x1BFEDF72L, 0x429B023DL,
0x37D0D724L, 0xD00A1248L, 0xDB0FEAD3L, 0x49F1C09BL,
0x075372C9L, 0x80991B7BL, 0x25D479D8L, 0xF6E8DEF7L,
0xE3FE501AL, 0xB6794C3BL, 0x976CE0BDL, 0x04C006BAL,
0xC1A94FB6L, 0x409F60C4L, 0x5E5C9EC2L, 0x196A2463L,
0x68FB6FAFL, 0x3E6C53B5L, 0x1339B2EBL, 0x3B52EC6FL,
0x6DFC511FL, 0x9B30952CL, 0xCC814544L, 0xAF5EBD09L,
0xBEE3D004L, 0xDE334AFDL, 0x660F2807L, 0x192E4BB3L,
0xC0CBA857L, 0x45C8740FL, 0xD20B5F39L, 0xB9D3FBDBL,
0x5579C0BDL, 0x1A60320AL, 0xD6A100C6L, 0x402C7279L,
0x679F25FEL, 0xFB1FA3CCL, 0x8EA5E9F8L, 0xDB3222F8L,
0x3C7516DFL, 0xFD616B15L, 0x2F501EC8L, 0xAD0552ABL,
0x323DB5FAL, 0xFD238760L, 0x53317B48L, 0x3E00DF82L,
0x9E5C57BBL, 0xCA6F8CA0L, 0x1A87562EL, 0xDF1769DBL,
0xD542A8F6L, 0x287EFFC3L, 0xAC6732C6L, 0x8C4F5573L,
0x695B27B0L, 0xBBCA58C8L, 0xE1FFA35DL, 0xB8F011A0L,
0x10FA3D98L, 0xFD2183B8L, 0x4AFCB56CL, 0x2DD1D35BL,
0x9A53E479L, 0xB6F84565L, 0xD28E49BCL, 0x4BFB9790L,
0xE1DDF2DAL, 0xA4CB7E33L, 0x62FB1341L, 0xCEE4C6E8L,
0xEF20CADAL, 0x36774C01L, 0xD07E9EFEL, 0x2BF11FB4L,
0x95DBDA4DL, 0xAE909198L, 0xEAAD8E71L, 0x6B93D5A0L,
0xD08ED1D0L, 0xAFC725E0L, 0x8E3C5B2FL, 0x8E7594B7L,
0x8FF6E2FBL, 0xF2122B64L, 0x8888B812L, 0x900DF01CL,
0x4FAD5EA0L, 0x688FC31CL, 0xD1CFF191L, 0xB3A8C1ADL,
0x2F2F2218L, 0xBE0E1777L, 0xEA752DFEL, 0x8B021FA1L,
0xE5A0CC0FL, 0xB56F74E8L, 0x18ACF3D6L, 0xCE89E299L,
0xB4A84FE0L, 0xFD13E0B7L, 0x7CC43B81L, 0xD2ADA8D9L,
0x165FA266L, 0x80957705L, 0x93CC7314L, 0x211A1477L,
0xE6AD2065L, 0x77B5FA86L, 0xC75442F5L, 0xFB9D35CFL,
0xEBCDAF0CL, 0x7B3E89A0L, 0xD6411BD3L, 0xAE1E7E49L,
0x00250E2DL, 0x2071B35EL, 0x226800BBL, 0x57B8E0AFL,
0x2464369BL, 0xF009B91EL, 0x5563911DL, 0x59DFA6AAL,
0x78C14389L, 0xD95A537FL, 0x207D5BA2L, 0x02E5B9C5L,
0x83260376L, 0x6295CFA9L, 0x11C81968L, 0x4E734A41L,
0xB3472DCAL, 0x7B14A94AL, 0x1B510052L, 0x9A532915L,
0xD60F573FL, 0xBC9BC6E4L, 0x2B60A476L, 0x81E67400L,
0x08BA6FB5L, 0x571BE91FL, 0xF296EC6BL, 0x2A0DD915L,
0xB6636521L, 0xE7B9F9B6L, 0xFF34052EL, 0xC5855664L,
0x53B02D5DL, 0xA99F8FA1L, 0x08BA4799L, 0x6E85076AL },
{ 0x4B7A70E9L, 0xB5B32944L, 0xDB75092EL, 0xC4192623L,
0xAD6EA6B0L, 0x49A7DF7DL, 0x9CEE60B8L, 0x8FEDB266L,
0xECAA8C71L, 0x699A17FFL, 0x5664526CL, 0xC2B19EE1L,
0x193602A5L, 0x75094C29L, 0xA0591340L, 0xE4183A3EL,
0x3F54989AL, 0x5B429D65L, 0x6B8FE4D6L, 0x99F73FD6L,
0xA1D29C07L, 0xEFE830F5L, 0x4D2D38E6L, 0xF0255DC1L,
0x4CDD2086L, 0x8470EB26L, 0x6382E9C6L, 0x021ECC5EL,
0x09686B3FL, 0x3EBAEFC9L, 0x3C971814L, 0x6B6A70A1L,
0x687F3584L, 0x52A0E286L, 0xB79C5305L, 0xAA500737L,
0x3E07841CL, 0x7FDEAE5CL, 0x8E7D44ECL, 0x5716F2B8L,
0xB03ADA37L, 0xF0500C0DL, 0xF01C1F04L, 0x0200B3FFL,
0xAE0CF51AL, 0x3CB574B2L, 0x25837A58L, 0xDC0921BDL,
0xD19113F9L, 0x7CA92FF6L, 0x94324773L, 0x22F54701L,
0x3AE5E581L, 0x37C2DADCL, 0xC8B57634L, 0x9AF3DDA7L,
0xA9446146L, 0x0FD0030EL, 0xECC8C73EL, 0xA4751E41L,
0xE238CD99L, 0x3BEA0E2FL, 0x3280BBA1L, 0x183EB331L,
0x4E548B38L, 0x4F6DB908L, 0x6F420D03L, 0xF60A04BFL,
0x2CB81290L, 0x24977C79L, 0x5679B072L, 0xBCAF89AFL,
0xDE9A771FL, 0xD9930810L, 0xB38BAE12L, 0xDCCF3F2EL,
0x5512721FL, 0x2E6B7124L, 0x501ADDE6L, 0x9F84CD87L,
0x7A584718L, 0x7408DA17L, 0xBC9F9ABCL, 0xE94B7D8CL,
0xEC7AEC3AL, 0xDB851DFAL, 0x63094366L, 0xC464C3D2L,
0xEF1C1847L, 0x3215D908L, 0xDD433B37L, 0x24C2BA16L,
0x12A14D43L, 0x2A65C451L, 0x50940002L, 0x133AE4DDL,
0x71DFF89EL, 0x10314E55L, 0x81AC77D6L, 0x5F11199BL,
0x043556F1L, 0xD7A3C76BL, 0x3C11183BL, 0x5924A509L,
0xF28FE6EDL, 0x97F1FBFAL, 0x9EBABF2CL, 0x1E153C6EL,
0x86E34570L, 0xEAE96FB1L, 0x860E5E0AL, 0x5A3E2AB3L,
0x771FE71CL, 0x4E3D06FAL, 0x2965DCB9L, 0x99E71D0FL,
0x803E89D6L, 0x5266C825L, 0x2E4CC978L, 0x9C10B36AL,
0xC6150EBAL, 0x94E2EA78L, 0xA5FC3C53L, 0x1E0A2DF4L,
0xF2F74EA7L, 0x361D2B3DL, 0x1939260FL, 0x19C27960L,
0x5223A708L, 0xF71312B6L, 0xEBADFE6EL, 0xEAC31F66L,
0xE3BC4595L, 0xA67BC883L, 0xB17F37D1L, 0x018CFF28L,
0xC332DDEFL, 0xBE6C5AA5L, 0x65582185L, 0x68AB9802L,
0xEECEA50FL, 0xDB2F953BL, 0x2AEF7DADL, 0x5B6E2F84L,
0x1521B628L, 0x29076170L, 0xECDD4775L, 0x619F1510L,
0x13CCA830L, 0xEB61BD96L, 0x0334FE1EL, 0xAA0363CFL,
0xB5735C90L, 0x4C70A239L, 0xD59E9E0BL, 0xCBAADE14L,
0xEECC86BCL, 0x60622CA7L, 0x9CAB5CABL, 0xB2F3846EL,
0x648B1EAFL, 0x19BDF0CAL, 0xA02369B9L, 0x655ABB50L,
0x40685A32L, 0x3C2AB4B3L, 0x319EE9D5L, 0xC021B8F7L,
0x9B540B19L, 0x875FA099L, 0x95F7997EL, 0x623D7DA8L,
0xF837889AL, 0x97E32D77L, 0x11ED935FL, 0x16681281L,
0x0E358829L, 0xC7E61FD6L, 0x96DEDFA1L, 0x7858BA99L,
0x57F584A5L, 0x1B227263L, 0x9B83C3FFL, 0x1AC24696L,
0xCDB30AEBL, 0x532E3054L, 0x8FD948E4L, 0x6DBC3128L,
0x58EBF2EFL, 0x34C6FFEAL, 0xFE28ED61L, 0xEE7C3C73L,
0x5D4A14D9L, 0xE864B7E3L, 0x42105D14L, 0x203E13E0L,
0x45EEE2B6L, 0xA3AAABEAL, 0xDB6C4F15L, 0xFACB4FD0L,
0xC742F442L, 0xEF6ABBB5L, 0x654F3B1DL, 0x41CD2105L,
0xD81E799EL, 0x86854DC7L, 0xE44B476AL, 0x3D816250L,
0xCF62A1F2L, 0x5B8D2646L, 0xFC8883A0L, 0xC1C7B6A3L,
0x7F1524C3L, 0x69CB7492L, 0x47848A0BL, 0x5692B285L,
0x095BBF00L, 0xAD19489DL, 0x1462B174L, 0x23820E00L,
0x58428D2AL, 0x0C55F5EAL, 0x1DADF43EL, 0x233F7061L,
0x3372F092L, 0x8D937E41L, 0xD65FECF1L, 0x6C223BDBL,
0x7CDE3759L, 0xCBEE7460L, 0x4085F2A7L, 0xCE77326EL,
0xA6078084L, 0x19F8509EL, 0xE8EFD855L, 0x61D99735L,
0xA969A7AAL, 0xC50C06C2L, 0x5A04ABFCL, 0x800BCADCL,
0x9E447A2EL, 0xC3453484L, 0xFDD56705L, 0x0E1E9EC9L,
0xDB73DBD3L, 0x105588CDL, 0x675FDA79L, 0xE3674340L,
0xC5C43465L, 0x713E38D8L, 0x3D28F89EL, 0xF16DFF20L,
0x153E21E7L, 0x8FB03D4AL, 0xE6E39F2BL, 0xDB83ADF7L },
{ 0xE93D5A68L, 0x948140F7L, 0xF64C261CL, 0x94692934L,
0x411520F7L, 0x7602D4F7L, 0xBCF46B2EL, 0xD4A20068L,
0xD4082471L, 0x3320F46AL, 0x43B7D4B7L, 0x500061AFL,
0x1E39F62EL, 0x97244546L, 0x14214F74L, 0xBF8B8840L,
0x4D95FC1DL, 0x96B591AFL, 0x70F4DDD3L, 0x66A02F45L,
0xBFBC09ECL, 0x03BD9785L, 0x7FAC6DD0L, 0x31CB8504L,
0x96EB27B3L, 0x55FD3941L, 0xDA2547E6L, 0xABCA0A9AL,
0x28507825L, 0x530429F4L, 0x0A2C86DAL, 0xE9B66DFBL,
0x68DC1462L, 0xD7486900L, 0x680EC0A4L, 0x27A18DEEL,
0x4F3FFEA2L, 0xE887AD8CL, 0xB58CE006L, 0x7AF4D6B6L,
0xAACE1E7CL, 0xD3375FECL, 0xCE78A399L, 0x406B2A42L,
0x20FE9E35L, 0xD9F385B9L, 0xEE39D7ABL, 0x3B124E8BL,
0x1DC9FAF7L, 0x4B6D1856L, 0x26A36631L, 0xEAE397B2L,
0x3A6EFA74L, 0xDD5B4332L, 0x6841E7F7L, 0xCA7820FBL,
0xFB0AF54EL, 0xD8FEB397L, 0x454056ACL, 0xBA489527L,
0x55533A3AL, 0x20838D87L, 0xFE6BA9B7L, 0xD096954BL,
0x55A867BCL, 0xA1159A58L, 0xCCA92963L, 0x99E1DB33L,
0xA62A4A56L, 0x3F3125F9L, 0x5EF47E1CL, 0x9029317CL,
0xFDF8E802L, 0x04272F70L, 0x80BB155CL, 0x05282CE3L,
0x95C11548L, 0xE4C66D22L, 0x48C1133FL, 0xC70F86DCL,
0x07F9C9EEL, 0x41041F0FL, 0x404779A4L, 0x5D886E17L,
0x325F51EBL, 0xD59BC0D1L, 0xF2BCC18FL, 0x41113564L,
0x257B7834L, 0x602A9C60L, 0xDFF8E8A3L, 0x1F636C1BL,
0x0E12B4C2L, 0x02E1329EL, 0xAF664FD1L, 0xCAD18115L,
0x6B2395E0L, 0x333E92E1L, 0x3B240B62L, 0xEEBEB922L,
0x85B2A20EL, 0xE6BA0D99L, 0xDE720C8CL, 0x2DA2F728L,
0xD0127845L, 0x95B794FDL, 0x647D0862L, 0xE7CCF5F0L,
0x5449A36FL, 0x877D48FAL, 0xC39DFD27L, 0xF33E8D1EL,
0x0A476341L, 0x992EFF74L, 0x3A6F6EABL, 0xF4F8FD37L,
0xA812DC60L, 0xA1EBDDF8L, 0x991BE14CL, 0xDB6E6B0DL,
0xC67B5510L, 0x6D672C37L, 0x2765D43BL, 0xDCD0E804L,
0xF1290DC7L, 0xCC00FFA3L, 0xB5390F92L, 0x690FED0BL,
0x667B9FFBL, 0xCEDB7D9CL, 0xA091CF0BL, 0xD9155EA3L,
0xBB132F88L, 0x515BAD24L, 0x7B9479BFL, 0x763BD6EBL,
0x37392EB3L, 0xCC115979L, 0x8026E297L, 0xF42E312DL,
0x6842ADA7L, 0xC66A2B3BL, 0x12754CCCL, 0x782EF11CL,
0x6A124237L, 0xB79251E7L, 0x06A1BBE6L, 0x4BFB6350L,
0x1A6B1018L, 0x11CAEDFAL, 0x3D25BDD8L, 0xE2E1C3C9L,
0x44421659L, 0x0A121386L, 0xD90CEC6EL, 0xD5ABEA2AL,
0x64AF674EL, 0xDA86A85FL, 0xBEBFE988L, 0x64E4C3FEL,
0x9DBC8057L, 0xF0F7C086L, 0x60787BF8L, 0x6003604DL,
0xD1FD8346L, 0xF6381FB0L, 0x7745AE04L, 0xD736FCCCL,
0x83426B33L, 0xF01EAB71L, 0xB0804187L, 0x3C005E5FL,
0x77A057BEL, 0xBDE8AE24L, 0x55464299L, 0xBF582E61L,
0x4E58F48FL, 0xF2DDFDA2L, 0xF474EF38L, 0x8789BDC2L,
0x5366F9C3L, 0xC8B38E74L, 0xB475F255L, 0x46FCD9B9L,
0x7AEB2661L, 0x8B1DDF84L, 0x846A0E79L, 0x915F95E2L,
0x466E598EL, 0x20B45770L, 0x8CD55591L, 0xC902DE4CL,
0xB90BACE1L, 0xBB8205D0L, 0x11A86248L, 0x7574A99EL,
0xB77F19B6L, 0xE0A9DC09L, 0x662D09A1L, 0xC4324633L,
0xE85A1F02L, 0x09F0BE8CL, 0x4A99A025L, 0x1D6EFE10L,
0x1AB93D1DL, 0x0BA5A4DFL, 0xA186F20FL, 0x2868F169L,
0xDCB7DA83L, 0x573906FEL, 0xA1E2CE9BL, 0x4FCD7F52L,
0x50115E01L, 0xA70683FAL, 0xA002B5C4L, 0x0DE6D027L,
0x9AF88C27L, 0x773F8641L, 0xC3604C06L, 0x61A806B5L,
0xF0177A28L, 0xC0F586E0L, 0x006058AAL, 0x30DC7D62L,
0x11E69ED7L, 0x2338EA63L, 0x53C2DD94L, 0xC2C21634L,
0xBBCBEE56L, 0x90BCB6DEL, 0xEBFC7DA1L, 0xCE591D76L,
0x6F05E409L, 0x4B7C0188L, 0x39720A3DL, 0x7C927C24L,
0x86E3725FL, 0x724D9DB9L, 0x1AC15BB4L, 0xD39EB8FCL,
0xED545578L, 0x08FCA5B5L, 0xD83D7CD3L, 0x4DAD0FC4L,
0x1E50EF5EL, 0xB161E6F8L, 0xA28514D9L, 0x6C51133CL,
0x6FD5C7E7L, 0x56E14EC4L, 0x362ABFCEL, 0xDDC6C837L,
0xD79A3234L, 0x92638212L, 0x670EFA8EL, 0x406000E0L },
{ 0x3A39CE37L, 0xD3FAF5CFL, 0xABC27737L, 0x5AC52D1BL,
0x5CB0679EL, 0x4FA33742L, 0xD3822740L, 0x99BC9BBEL,
0xD5118E9DL, 0xBF0F7315L, 0xD62D1C7EL, 0xC700C47BL,
0xB78C1B6BL, 0x21A19045L, 0xB26EB1BEL, 0x6A366EB4L,
0x5748AB2FL, 0xBC946E79L, 0xC6A376D2L, 0x6549C2C8L,
0x530FF8EEL, 0x468DDE7DL, 0xD5730A1DL, 0x4CD04DC6L,
0x2939BBDBL, 0xA9BA4650L, 0xAC9526E8L, 0xBE5EE304L,
0xA1FAD5F0L, 0x6A2D519AL, 0x63EF8CE2L, 0x9A86EE22L,
0xC089C2B8L, 0x43242EF6L, 0xA51E03AAL, 0x9CF2D0A4L,
0x83C061BAL, 0x9BE96A4DL, 0x8FE51550L, 0xBA645BD6L,
0x2826A2F9L, 0xA73A3AE1L, 0x4BA99586L, 0xEF5562E9L,
0xC72FEFD3L, 0xF752F7DAL, 0x3F046F69L, 0x77FA0A59L,
0x80E4A915L, 0x87B08601L, 0x9B09E6ADL, 0x3B3EE593L,
0xE990FD5AL, 0x9E34D797L, 0x2CF0B7D9L, 0x022B8B51L,
0x96D5AC3AL, 0x017DA67DL, 0xD1CF3ED6L, 0x7C7D2D28L,
0x1F9F25CFL, 0xADF2B89BL, 0x5AD6B472L, 0x5A88F54CL,
0xE029AC71L, 0xE019A5E6L, 0x47B0ACFDL, 0xED93FA9BL,
0xE8D3C48DL, 0x283B57CCL, 0xF8D56629L, 0x79132E28L,
0x785F0191L, 0xED756055L, 0xF7960E44L, 0xE3D35E8CL,
0x15056DD4L, 0x88F46DBAL, 0x03A16125L, 0x0564F0BDL,
0xC3EB9E15L, 0x3C9057A2L, 0x97271AECL, 0xA93A072AL,
0x1B3F6D9BL, 0x1E6321F5L, 0xF59C66FBL, 0x26DCF319L,
0x7533D928L, 0xB155FDF5L, 0x03563482L, 0x8ABA3CBBL,
0x28517711L, 0xC20AD9F8L, 0xABCC5167L, 0xCCAD925FL,
0x4DE81751L, 0x3830DC8EL, 0x379D5862L, 0x9320F991L,
0xEA7A90C2L, 0xFB3E7BCEL, 0x5121CE64L, 0x774FBE32L,
0xA8B6E37EL, 0xC3293D46L, 0x48DE5369L, 0x6413E680L,
0xA2AE0810L, 0xDD6DB224L, 0x69852DFDL, 0x09072166L,
0xB39A460AL, 0x6445C0DDL, 0x586CDECFL, 0x1C20C8AEL,
0x5BBEF7DDL, 0x1B588D40L, 0xCCD2017FL, 0x6BB4E3BBL,
0xDDA26A7EL, 0x3A59FF45L, 0x3E350A44L, 0xBCB4CDD5L,
0x72EACEA8L, 0xFA6484BBL, 0x8D6612AEL, 0xBF3C6F47L,
0xD29BE463L, 0x542F5D9EL, 0xAEC2771BL, 0xF64E6370L,
0x740E0D8DL, 0xE75B1357L, 0xF8721671L, 0xAF537D5DL,
0x4040CB08L, 0x4EB4E2CCL, 0x34D2466AL, 0x0115AF84L,
0xE1B00428L, 0x95983A1DL, 0x06B89FB4L, 0xCE6EA048L,
0x6F3F3B82L, 0x3520AB82L, 0x011A1D4BL, 0x277227F8L,
0x611560B1L, 0xE7933FDCL, 0xBB3A792BL, 0x344525BDL,
0xA08839E1L, 0x51CE794BL, 0x2F32C9B7L, 0xA01FBAC9L,
0xE01CC87EL, 0xBCC7D1F6L, 0xCF0111C3L, 0xA1E8AAC7L,
0x1A908749L, 0xD44FBD9AL, 0xD0DADECBL, 0xD50ADA38L,
0x0339C32AL, 0xC6913667L, 0x8DF9317CL, 0xE0B12B4FL,
0xF79E59B7L, 0x43F5BB3AL, 0xF2D519FFL, 0x27D9459CL,
0xBF97222CL, 0x15E6FC2AL, 0x0F91FC71L, 0x9B941525L,
0xFAE59361L, 0xCEB69CEBL, 0xC2A86459L, 0x12BAA8D1L,
0xB6C1075EL, 0xE3056A0CL, 0x10D25065L, 0xCB03A442L,
0xE0EC6E0EL, 0x1698DB3BL, 0x4C98A0BEL, 0x3278E964L,
0x9F1F9532L, 0xE0D392DFL, 0xD3A0342BL, 0x8971F21EL,
0x1B0A7441L, 0x4BA3348CL, 0xC5BE7120L, 0xC37632D8L,
0xDF359F8DL, 0x9B992F2EL, 0xE60B6F47L, 0x0FE3F11DL,
0xE54CDA54L, 0x1EDAD891L, 0xCE6279CFL, 0xCD3E7E6FL,
0x1618B166L, 0xFD2C1D05L, 0x848FD2C5L, 0xF6FB2299L,
0xF523F357L, 0xA6327623L, 0x93A83531L, 0x56CCCD02L,
0xACF08162L, 0x5A75EBB5L, 0x6E163697L, 0x88D273CCL,
0xDE966292L, 0x81B949D0L, 0x4C50901BL, 0x71C65614L,
0xE6C6C7BDL, 0x327A140AL, 0x45E1D006L, 0xC3F27B9AL,
0xC9AA53FDL, 0x62A80F00L, 0xBB25BFE2L, 0x35BDD2F6L,
0x71126905L, 0xB2040222L, 0xB6CBCF7CL, 0xCD769C2BL,
0x53113EC0L, 0x1640E3D3L, 0x38ABBD60L, 0x2547ADF0L,
0xBA38209CL, 0xF746CE76L, 0x77AFA1C5L, 0x20756060L,
0x85CBFE4EL, 0x8AE88DD8L, 0x7AAAF9B0L, 0x4CF9AA7EL,
0x1948C25CL, 0x02FB8A8CL, 0x01C36AE4L, 0xD6EBE1F9L,
0x90D4F869L, 0xA65CDEA0L, 0x3F09252DL, 0xC208E69FL,
0xB74E6132L, 0xCE77E25BL, 0x578FDFE3L, 0x3AC372E6L }
};
static uint32_t F(BLOWFISH_CTX* ctx, uint32_t x) {
uint16_t a, b, c, d;
uint32_t y;
d = (uint16_t)(x & 0xFF);
x >>= 8;
c = (uint16_t)(x & 0xFF);
x >>= 8;
b = (uint16_t)(x & 0xFF);
x >>= 8;
a = (uint16_t)(x & 0xFF);
y = ctx->S[0][a] + ctx->S[1][b];
y = y ^ ctx->S[2][c];
y = y + ctx->S[3][d];
return y;
}
void Blowfish_Encrypt(BLOWFISH_CTX* ctx, uint32_t* xl, uint32_t* xr) {
uint32_t Xl;
uint32_t Xr;
uint32_t temp;
int16_t i;
Xl = *xl;
Xr = *xr;
for (i = 0; i < N; ++i) {
Xl = Xl ^ ctx->P[i];
Xr = F(ctx, Xl) ^ Xr;
temp = Xl;
Xl = Xr;
Xr = temp;
}
temp = Xl;
Xl = Xr;
Xr = temp;
Xr = Xr ^ ctx->P[N];
Xl = Xl ^ ctx->P[N + 1];
*xl = Xl;
*xr = Xr;
}
void Blowfish_Decrypt(BLOWFISH_CTX* ctx, uint32_t* xl, uint32_t* xr) {
uint32_t Xl;
uint32_t Xr;
uint32_t temp;
int16_t i;
Xl = *xl;
Xr = *xr;
for (i = N + 1; i > 1; --i) {
Xl = Xl ^ ctx->P[i];
Xr = F(ctx, Xl) ^ Xr;
/* Exchange Xl and Xr */
temp = Xl;
Xl = Xr;
Xr = temp;
}
/* Exchange Xl and Xr */
temp = Xl;
Xl = Xr;
Xr = temp;
Xr = Xr ^ ctx->P[1];
Xl = Xl ^ ctx->P[0];
*xl = Xl;
*xr = Xr;
}
void Blowfish_Init(BLOWFISH_CTX* ctx, uint8_t* key, int32_t keyLen) {
int32_t i, j, k;
uint32_t data, datal, datar;
for (i = 0; i < 4; i++) {
for (j = 0; j < 256; j++)
ctx->S[i][j] = ORIG_S[i][j];
}
j = 0;
for (i = 0; i < N + 2; ++i) {
data = 0x00000000;
for (k = 0; k < 4; ++k) {
data = (data << 8) | key[j];
j = j + 1;
if (j >= keyLen)
j = 0;
}
ctx->P[i] = ORIG_P[i] ^ data;
}
datal = 0x00000000;
datar = 0x00000000;
for (i = 0; i < N + 2; i += 2) {
Blowfish_Encrypt(ctx, &datal, &datar);
ctx->P[i] = datal;
ctx->P[i + 1] = datar;
}
for (i = 0; i < 4; ++i) {
for (j = 0; j < 256; j += 2) {
Blowfish_Encrypt(ctx, &datal, &datar);
ctx->S[i][j] = datal;
ctx->S[i][j + 1] = datar;
}
}
}
union
{
char AsChar[32];
unsigned char AsU8[32];
unsigned int AsUInt[8];
unsigned long long AsU64[4];
} flag;
void rc4_init(unsigned char* s, unsigned char* key, size_t Len)
{
int i = 0, j = 0;
char k[256] = { 0 };
unsigned char tmp = 0;
for (i = 0; i < 256; i++) {
s[i] = i;
k[i] = key[i % Len];
}
for (i = 0; i < 256; i++) {
j = (j + s[i] + k[i]) % 256;
tmp = s[i];
s[i] = s[j];
s[j] = tmp;
}
}
void rc4_decrypt(unsigned char* s, unsigned char* Data, size_t Len)
{
int i = 0, j = 0, t = 0;
size_t k = 0;
unsigned char tmp;
for (k = 0; k < Len; k++) {
i = (i + 1) % 256;
j = (j + s[i]) % 256;
tmp = s[i];
s[i] = s[j];
s[j] = tmp;
t = (s[i] + s[j]) % 256;
// Data[k] ^= s[t];
Data[k] -= s[t] + 16 - 0x178B1710;
}
}
int main()
{
flag.AsU64[0] = 0xBCB6C065E9B49472LL;
flag.AsU64[1] = 0xDBD7F8723B1F9F9CLL;
flag.AsU64[2] = 0x925740C949C6E3CDLL;
flag.AsU64[3] = 0x6B18711A0CF70D06LL;
char rc4_key[] = "i_am_a_fish_man";
char bf_key[] = "fishrman";
unsigned char sbox[256];
rc4_init(sbox, (unsigned char*)rc4_key, 15);
rc4_decrypt(sbox, flag.AsU8, 32);
BLOWFISH_CTX ctx;
Blowfish_Init(&ctx, (uint8_t*)bf_key, 8);
Blowfish_Decrypt(&ctx, &flag.AsUInt[0], &flag.AsUInt[1]);
Blowfish_Decrypt(&ctx, &flag.AsUInt[2], &flag.AsUInt[3]);
Blowfish_Decrypt(&ctx, &flag.AsUInt[4], &flag.AsUInt[5]);
Blowfish_Decrypt(&ctx, &flag.AsUInt[6], &flag.AsUInt[7]);
printf("%32s\n", flag.AsChar);
return 0;
}比赛前两天刚换了硬盘，比赛的时候环境还没重新配好，直接开躺，结果中午配好环境后十分钟就做出来了，真没绷住
中午好不容易把环境重新配了，下午一来又是ollvm混淆，直接还是D810上去，发现直接就是
__int64 __fastcall main(int a1, char **a2, char **a3)
{
// [COLLAPSED LOCAL DECLARATIONS. PRESS KEYPAD CTRL-"+" TO EXPAND]
v10 = __readfsqword(0x28u);
puts("input");
memset(s, 0, sizeof(s));
read(0, s, 0x20uLL);
len = strlen(s);
s1 = (char *)sub_11B0(s, len);
v8 = strcmp(s1, "rfGdGqQdsRwTGJSisXK/GgYbGMQircAcsJwRGXrhIJG=");
v3 = 0xD2281AA2;
if ( v8 )
v3 = 0x14DF5426;
if ( v3 == 0xD2281AA2 )
{
v7 = 0;
printf("you are right");
}
else
{
v7 = -1;
printf("Wrong");
}
return v7;
}一眼base64，实际上还换了个表，直接开CyberChef解就行，可惜手慢了没抢到一血。
rfGdGqQdsRwTGJSisXK/GgYbGMQircAcsJwRGXrhIJG=
ABCJKLMNODEFGHIPQUVXYZfarstuvwxyz0WRSTq123456789+/bcdeghijklmnop
对着给的脚本反过来写就行，没啥难度。算是让我搞懂了huffman-tree的原理倒是）
import lzma
f = lzma.open('compressed.lzma', 'rb')
code_dict_count = ord(f.read(1))
code_dict = {}
for i in range(code_dict_count):
symbol = ord(f.read(1))
code_len = ord(f.read(1))
code = f.read(1)
tmp = bin(ord(code))[2:]
front_len = code_len - len(tmp)
prefix = '0' * front_len + tmp
code_dict[symbol] = prefix
data = f.read()
padded_data = ''
for b in data:
t = bin(b)[2:]
front_len = 8 - len(t)
item = '0' * front_len + t
padded_data += item
result = ''
try: # dunno how to resolve the padding though
temp = padded_data
while True:
current = ''
current_sym = ''
for symbol, code in code_dict.items():
if code == temp[:len(code)]:
if len(code) > len(current):
current = code
current_sym = symbol
result += chr(current_sym)
temp = temp[len(current):]
except:
print(result)多的别问，问就是不会，没做出来（菜狗是这样的）