Objective C / C. I get wrong Value when i try to get Mac Adress on IOS device - ios

Question

I'm trying to use a C code to obtain mac adress on any IOS device.
I'm trying it on a iPhone 6 plus but it seems not work.
My output will look as follows:
2015-02-15 15:37:37.947 MyDemo[438:223963] Mac Address: 02:00:00:00:00:00
Anyone can help me for this please ?
Thanks.
This is the GetMacAdress.m
Original source code courtesy John from iOSDeveloperTips.com
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_dl.h>
...
- (NSString *)getMacAddress
{
int mgmtInfoBase[6];
char *msgBuffer = NULL;
size_t length;
unsigned char macAddress[6];
struct if_msghdr *interfaceMsgStruct;
struct sockaddr_dl *socketStruct;
NSString *errorFlag = NULL;
// Setup the management Information Base (mib)
mgmtInfoBase[0] = CTL_NET; // Request network subsystem
mgmtInfoBase[1] = AF_ROUTE; // Routing table info
mgmtInfoBase[2] = 0;
mgmtInfoBase[3] = AF_LINK; // Request link layer information
mgmtInfoBase[4] = NET_RT_IFLIST; // Request all configured interfaces
// With all configured interfaces requested, get handle index
if ((mgmtInfoBase[5] = if_nametoindex("en0")) == 0)
errorFlag = #"if_nametoindex failure";
else
{
// Get the size of the data available (store in len)
if (sysctl(mgmtInfoBase, 6, NULL, &length, NULL, 0) < 0)
errorFlag = #"sysctl mgmtInfoBase failure";
else
{
// Alloc memory based on above call
if ((msgBuffer = malloc(length)) == NULL)
errorFlag = #"buffer allocation failure";
else
{
// Get system information, store in buffer
if (sysctl(mgmtInfoBase, 6, msgBuffer, &length, NULL, 0) < 0)
errorFlag = #"sysctl msgBuffer failure";
}
}
}
// Befor going any further...
if (errorFlag != NULL)
{
NSLog(#"Error: %#", errorFlag);
return errorFlag;
}
// Map msgbuffer to interface message structure
interfaceMsgStruct = (struct if_msghdr *) msgBuffer;
// Map to link-level socket structure
socketStruct = (struct sockaddr_dl *) (interfaceMsgStruct + 1);
// Copy link layer address data in socket structure to an array
memcpy(&macAddress, socketStruct->sdl_data + socketStruct->sdl_nlen, 6);
// Read from char array into a string object, into traditional Mac address format
NSString *macAddressString = [NSString stringWithFormat:#"%02X:%02X:%02X:%02X:%02X:%02X",
macAddress[0], macAddress[1], macAddress[2],
macAddress[3], macAddress[4], macAddress[5]];
NSLog(#"Mac Address: %#", macAddressString);
// Release the buffer memory
free(msgBuffer);
return macAddressString;
}

Answer 1

That is some pretty nasty low-level code.
I personally think that anyone who writes code of the form:
if ((a=b)==c)
...should be shot. We're not writing assembler here - Don't write code that looks like a typo to save 1 statement. (That rant is directed at the original author, not you.)
I'm not familiar enough with the low-level system functions to be able to tell what's wrong without a lot of digging.
However, stepping back from why your code isn't working, WHY do you need the MAC address? Does it have to be the actual network MAC address?
Apple no longer allows you to get that information because it allows you to uniquely track the user's device. If you do find a way to do it, your app will be rejected. (Not really Apple's fault; there was a big stink in the industry and all the device vendors had to block providing this info.)
#mad_mask's suggestion of using identifierForVendor is probably the best solution. That gives you an ID that's unique for that device for your company.

Answer 2

It is not possible to get the MAC address for an apple device any longer. This was added to prevent applications from using the MAC address as a unique identifier for tracking. It always comes out as 02:00:00:00:00:00 regardless of the route you take to finding it.
The vendor and marketing Ids you have to use instead are not the MAC address but something else.
I have written a network scanner and as far as I have been able to tell, there is no way round this unless you can talk to an external device on the same LAN segment which has visibility of the device on the network and can send it to you.