AdExtensions.m

//
//  AdExtensions.m
//  securesubmission
//
//  Created by AdDash on 8/17/11.
//  Copyright (c) 2011 __MyCompanyName__. All rights reserved.
//

#import "AdExtensions.h"
#import <CommonCrypto/CommonDigest.h>
#import <CommonCrypto/CommonHMAC.h>

//these includes are required for the UIDevice extensions from
//https://github.com/gekitz/UIDevice-with-UniqueIdentifier-for-iOS-5
#include <sys/socket.h> // Per msqr
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_dl.h>



@implementation NSString (AdExtensions)
-(NSString *) md5 {
    const char *cStr = [self UTF8String];
    unsigned char result[CC_MD5_DIGEST_LENGTH];
    CC_MD5( cStr, strlen(cStr), result ); // This is the md5 call
    return [NSString stringWithFormat:
            @"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
            result[0], result[1], result[2], result[3], 
            result[4], result[5], result[6], result[7],
            result[8], result[9], result[10], result[11],
            result[12], result[13], result[14], result[15]
            ];  
}

+ (NSString *)URLEncodeString:(NSString *)string { 
    NSString *result = (NSString *)CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (CFStringRef)string, NULL, CFSTR("% '\"?=&+<>;:-"), kCFStringEncodingUTF8); 
    
    return [result autorelease]; 
} 

- (NSString *)URLEncodeString { 
    return [NSString URLEncodeString:self]; 
} 
@end

@implementation NSData (AdExtensions)
-(NSData*)dataByHmacSHA256EncryptingWithKey:(NSData*)key {   
    void *buffer = malloc(CC_SHA256_DIGEST_LENGTH);
    CCHmac(kCCHmacAlgSHA256, [key bytes], [key length], [self bytes], [self length], buffer);
    return [NSData dataWithBytesNoCopy:buffer length:CC_SHA256_DIGEST_LENGTH freeWhenDone:YES];
}

- (NSString*)stringWithHexBytes {
    static const char hexdigits[] = "0123456789abcdef";
    const size_t numBytes = [self length];
    const unsigned char* bytes = [self bytes];
    char *strbuf = (char *)malloc(numBytes * 2 + 1);
    char *hex = strbuf;
    NSString *hexBytes = nil;
    
    for (int i = 0; i< numBytes; ++i) {
        const unsigned char c = *bytes++;
        *hex++ = hexdigits[(c >> 4) & 0xF];
        *hex++ = hexdigits[(c ) & 0xF];
    }
    *hex = 0;
    hexBytes = [NSString stringWithUTF8String:strbuf];
    free(strbuf);
    return hexBytes;
}

+(NSData*)dataWithRandomBytes:(int)length {
    if (length % 4 != 0) {
        [NSException raise:@"Invalid length for random data" format:@"%i is not divisible by 4 and this lame ass method requires it to be.",length];
    }
    NSMutableData* randomData = [NSMutableData dataWithCapacity:length];
    for( int i = 0 ; i < length/4 ; ++i ) { 
        unsigned int randomBits = arc4random();
        [randomData appendBytes:(void*)&randomBits length:4];
    }
    return randomData;
}
@end


//from https://github.com/gekitz/UIDevice-with-UniqueIdentifier-for-iOS-5
@interface UIDevice(Private)

- (NSString *) macaddress;

@end

@implementation UIDevice (IdentifierAddition)

////////////////////////////////////////////////////////////////////////////////
#pragma mark -
#pragma mark Private Methods

// Return the local MAC addy
// Courtesy of FreeBSD hackers email list
// Accidentally munged during previous update. Fixed thanks to erica sadun & mlamb.
- (NSString *) macaddress{
    
    int                 mib[6];
    size_t              len;
    char                *buf;
    unsigned char       *ptr;
    struct if_msghdr    *ifm;
    struct sockaddr_dl  *sdl;
    
    mib[0] = CTL_NET;
    mib[1] = AF_ROUTE;
    mib[2] = 0;
    mib[3] = AF_LINK;
    mib[4] = NET_RT_IFLIST;
    
    if ((mib[5] = if_nametoindex("en0")) == 0) {
        printf("Error: if_nametoindex error\n");
        return NULL;
    }
    
    if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
        printf("Error: sysctl, take 1\n");
        return NULL;
    }
    
    if ((buf = malloc(len)) == NULL) {
        printf("Could not allocate memory. error!\n");
        return NULL;
    }
    
    if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
        printf("Error: sysctl, take 2");
        return NULL;
    }
    
    ifm = (struct if_msghdr *)buf;
    sdl = (struct sockaddr_dl *)(ifm + 1);
    ptr = (unsigned char *)LLADDR(sdl);
    NSString *outstring = [NSString stringWithFormat:@"%02X:%02X:%02X:%02X:%02X:%02X", 
                           *ptr, *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5)];
    free(buf);
    
    return outstring;
}

////////////////////////////////////////////////////////////////////////////////
#pragma mark -
#pragma mark Public Methods

- (NSString *) uniqueDeviceIdentifier{
    NSString *macaddress = [[UIDevice currentDevice] macaddress];
    NSString *bundleIdentifier = [[NSBundle mainBundle] bundleIdentifier];
    
    NSString *stringToHash = [NSString stringWithFormat:@"%@%@",macaddress,bundleIdentifier];
    NSString *uniqueIdentifier = [stringToHash md5];
    
    return uniqueIdentifier;
}

- (NSString *) uniqueGlobalDeviceIdentifier{
    NSString *macaddress = [[UIDevice currentDevice] macaddress];
    NSString *uniqueIdentifier = [macaddress md5];
    
    return uniqueIdentifier;
}

@end