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[FerrariX]

Originally Posted by Shmoopi

The last method I have for you today is the best:

#import 
#import 
#import 

/* The encryption info struct and constants are missing from the iPhoneSimulator SDK, but not from the iPhoneOS or
 * Mac OS X SDKs. Since one doesn't ever ship a Simulator binary, we'll just provide the definitions here. */
#if TARGET_IPHONE_SIMULATOR && !defined(LC_ENCRYPTION_INFO)
#define LC_ENCRYPTION_INFO 0x21
struct encryption_info_command {
    uint32_t cmd;
    uint32_t cmdsize;
    uint32_t cryptoff;
    uint32_t cryptsize;
    uint32_t cryptid;
};
#endif

int main (int argc, char *argv[]);

static BOOL is_encrypted () {
    const struct mach_header *header;
    Dl_info dlinfo;
	
    /* Fetch the dlinfo for main() */
    if (dladdr(main, &dlinfo) == 0 || dlinfo.dli_fbase == NULL) {
        NSLog(@"Could not find main() symbol (very odd)");
        return NO;
    }
    header = dlinfo.dli_fbase;
	
    /* Compute the image size and search for a UUID */
    struct load_command *cmd = (struct load_command *) (header+1);
	
    for (uint32_t i = 0; cmd != NULL && i < header->ncmds; i++) {
        /* Encryption info segment */
        if (cmd->cmd == LC_ENCRYPTION_INFO) {
            struct encryption_info_command *crypt_cmd = (struct encryption_info_command *) cmd;
            /* Check if binary encryption is enabled */
            if (crypt_cmd->cryptid < 1) {
                /* Disabled, probably pirated */
                return NO;
            }
			
            /* Probably not pirated? */
            return YES;
        }
		
        cmd = (struct load_command *) ((uint8_t *) cmd + cmd->cmdsize);
    }
	
    /* Encryption info not found */
    return NO;
}

This is one of the best Anti-Piracy implementations that I've seen; no strings attached What you're doing here is taking the Executable file and checking to see if their is any encryption on it. You can also check this on your mac by taking an executable file and typing in "otool -l *exectuable file*" in terminal. you can also check out Dr. Touch's Anti-Crack commercial to see it in action. Whenever a pirate cracks an application it strips the encryption in order to run it, with this implementation it's very easy to check if your executable is encrypted.

Continued...

Hi Shmoopi,

Thanks for sharing the great info.

where do i put that last block of code for encryption check?
Also, do I need to call this method then do something w/ it output?


Doesn't sdk3.0+ has a function that is something like IsAppLegitCheck?

I'm not sure if it's any good though.

Can you please tell me how can I crack my app to check this?
(please PM me if required)

Thanks again,

-FerrariX