iOS安全防护系列之字符串及系统函数隐藏详解

//测试环境static NSString * KEY(){ unsigned char key[] = {  (pw_encrypt_key ^ 'a'),(pw_encrypt_key ^ '2'),(pw_encrypt_key ^ 's'),(pw_encrypt_key ^ '5'),(pw_encrypt_key ^ '4'),(pw_encrypt_key ^ 'b'),  (pw_encrypt_key ^ 'e'),(pw_encrypt_key ^ '5'),(pw_encrypt_key ^ 'f'),(pw_encrypt_key ^ '3'),(pw_encrypt_key ^ 'f'),(pw_encrypt_key ^ '4'),  (pw_encrypt_key ^ 'f'),  (pw_encrypt_key ^ '/0') }; unsigned char *p = key; while (((*p) ^= pw_encrypt_key) != '/0') {  p++; } return [NSString stringWithUTF8String:(const char *)key];}

#import <dlfcn.h>//句柄 void * handle = dlopen("/usr/lib/system/libcommonCrypto.dylib",RTLD_LAZY);

 unsigned char str[] = {  ('a' ^ 'C'),  ('a' ^ 'C'),  ('a' ^ 'C'),  ('a' ^ 'r'),  ('a' ^ 'y'),  ('a' ^ 'p'),  ('a' ^ 't'),  ('a' ^ 'o'),  ('a' ^ 'r'),  ('a' ^ 'C'),  ('a' ^ 'r'),  ('a' ^ 'e'),  ('a' ^ 'a'),  ('a' ^ 't'),  ('a' ^ 'e'),  ('a' ^ '/0') }; unsigned char * p = str; while (((*p) ^= 'a') != '/0') p++;CCCryptorStatus (* CCCryptorCreate_p)(         CCOperation op,    /* kCCEncrypt, etc. */         CCAlgorithm alg,   /* kCCAlgorithmDES, etc. */         CCOptions options,   /* kCCOptionPKCS7Padding, etc. */         const void *key,   /* raw key material */         size_t keyLength,         const void *iv,    /* optional initialization vector */         CCCryptorRef *cryptorRef) /* RETURNED */ __OSX_AVAILABLE_STARTING(__MAC_10_4, __IPHONE_2_0) = dlsym(handle, (const char *)str);

 status = CCCryptorCreate_p( kCCEncrypt, algorithm, options,         [keyData bytes], [keyData length], [ivData bytes],         &cryptor );