获取设备的MAC地址以及IP地址

今天写项目的时候需要获取手机设备的MAC地址以及IP地址，网上看了很多文章，虽然有些都是大同小异，虽然不是很明白代码的意思，但是在demo中贴上代码却发现红色的报错，后来才知道是没有引用库文件，也给自己提了个醒，如果时间允许的情况下还是要仔细的研究一下是怎么实现的，虽然可以直接用，但是懂了总比一直借用的好。废话不多说，算是记录一下吧。

引用头文件

//用于获取mac地址
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_dl.h>
//用于获取ip地址
#import <ifaddrs.h>
#include <arpa/inet.h>

获取IP地址

+ (NSString *)getIPAddress
{
    NSString *address = @"";
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *temp_addr = NULL;
    int success = 0;
    // retrieve the current interfaces - returns 0 on success
    success = getifaddrs(&interfaces);
    if (success == 0) {
        // Loop through linked list of interfaces
        temp_addr = interfaces;
        while(temp_addr != NULL) {
            if(temp_addr->ifa_addr->sa_family == AF_INET) {
                // Check if interface is en0 which is the wifi connection on the iPhone
                if([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"])
                {
                    // Get NSString from C String
                    address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];
                }
            }
            temp_addr = temp_addr->ifa_next;
        }
    }
    // Free memory
    freeifaddrs(interfaces);
    return address;
}

获取MAC地址

+ (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;
}

顺带说一下，获取设备的唯一标识符UDID现在苹果已经禁止了，所以很多都使用UUID来代替，但是会存在卸载或者更新等UUID改变的情况，所以想要保证UUID的唯一性可以使用keyChain来存储，这样获每次取到的就是唯一的了，除非你刷机（至于越狱是不是受影响我也没测试过）。
有需要的可以借鉴这篇文章： https://www.jianshu.com/p/faa4854ce180