MAC地址(MAC Address)
MAC(Medium/Media Access Control)地址,或称为 MAC位址、逻辑地址,用来定义网络设备的位置,由48比特长,12个的16进制数字组成,0到23位是厂商向IETF等机构申请用来标识厂商的代码,也称为“编制上唯一的标识符”(Organizationally Unique Identifier)。是识别LAN(局域网)结点的标志。地址的24到47位由厂商自行分派,是各个厂商制造的所有网卡的一个唯一编号。在OSI模型中,第三层网络层负责 IP地址,第二层数据链路层则负责 MAC位址。因此一个网卡会有一个全球唯一固定的MAC地址,但可对应多个IP地址。第48位是组播地址标志位。
获取ios的MAC地址
#include <sys/socket.h> // Per msqr
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_dl.h>
#pragma mark MAC
// Return the local MAC addy
// Courtesy of FreeBSD hackers email list
// Accidentally munged during previous update. Fixed thanks 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), *(ptr+4), *(ptr+5)];
free(buf);
return [outstring uppercaseString];
}
http://blog.youkuaiyun.com/doubleuto/article/details/6599516