How IOS gets the phone's MAC address _ios

First of all, the following two methods can get the phone's MAC address, but there is a limit, in the iOS7 below can be obtained. IOS7 after the Apple for SYSCTL and IOCTL technical processing, MAC address returned are 02:00:00:00:00:00.

It is written in the official document:

"Twolow-level networking APIs that used to return a MAC address now return thefixed value 02:00:00:00:00:00." The APIs in question are Sysctl (net_rt_iflist) and IOCTL (siocgifconf). Developers using the value of the MAC address should migrate toidentifiers such as-[uidevice Identifierforvendor]. This is affects all apps running on IOS 7 ".

So after IOS7 want to get the device's only label MAC address has been dead, can only be replaced by other.
Here are two ways:
Need to import several header files

#include <sys/sysctl.h> 
#include <net/if.h> 
#include <net/if_dl.h> 

Method 1:

Return to the local MAC addy//courtesy of FreeBSD Hackers email list//accidentally munged during-previous update. 
Fixed to 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)]; NSString *outstring = [NSString stringwithformat:@ "%02x%02x%02x%02x%02x%02x", *ptr, * (ptr+1), * (ptr+2), * (ptr+3), * (P 
   
  TR+4), * (ptr+5)]; 
   
  NSLog (@ "outstring:%@", outstring); 
   
  Free (BUF); 
return [outstring uppercasestring]; }

  Method 2:

 -(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 the all configured interfaces requested, get handle index if (mgmtinfo 
  BASE[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, NU 
    LL, 0) < 0) Errorflag = @ "Sysctl mgmtinfobase failure"; else {//Alloc Memory based on above call if ((Msgbuffer = malloc (length)) = = NULL) Errorflag = @ "Buffer allocation fail 
      Ure "; else {//Get system information, store in buffer if (Sysctl (Mgmtinfobase, 6, Msgbuffer, &len 
      Gth, 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 a array memcpy (&macaddress, Socketstruct->sdl_data + Soc 
   
  Ketstruct->sdl_nlen, 6); Read from char array into a string object, to traditional MAC address format nsstring *macaddressstring = [Nsstrin G Stringwithformat:@ "%02x:%02x:%02x:%02x:%02x:%02x", Macaddress[0], macaddress[1], macaddress[2], 
  MACADDRESS[3], macaddress[4], macaddress[5]; 
   
  NSLog (@ "MAC address:%@", macaddressstring); 
   
  Release of the buffer memory free (msgbuffer); 
return macaddressstring; 
 }

The above is iOS access to the phone's MAC address two ways, I hope to help you learn.