[Obj-C] Get IP address.

IPAddress.h

//
//  IPAddress.h
//
//  Created by Hituzi Ando on 2017/10/26.
//

#import <Foundation/Foundation.h>

NS_ASSUME_NONNULL_BEGIN

@interface IPAddress : NSObject

+ (NSString *)getCellularIPv4Address;
+ (NSString *)getCellularIPv6Address;
+ (NSString *)getWiFiIPv4Address;
+ (NSString *)getWiFiIPv6Address;

@end

NS_ASSUME_NONNULL_END

IPAddress.m

//
//  IPAddress.m
//
//  Created by Hituzi Ando on 2017/10/26.
//

#import <ifaddrs.h>
#import <arpa/inet.h>

#import "IPAddress.h"

@implementation IPAddress

+ (NSString *)getCellularIPv4Address {
    NSString *ip;
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *tempAddr = NULL;
    int success = 0;
    
    success = getifaddrs(&interfaces);
    
    if (success == 0) {
        tempAddr = interfaces;
        
        while (tempAddr != NULL) {
            if (tempAddr->ifa_addr->sa_family == AF_INET) { // IPv4
                if ([[NSString stringWithUTF8String:tempAddr->ifa_name] isEqualToString:@"pdp_ip0"]) {  // Cellular
                    char buff[256];
                    memset(buff, 0, sizeof(buff));
                    inet_ntop(AF_INET, &((struct sockaddr_in *) tempAddr->ifa_addr)->sin_addr, buff, sizeof(buff));
                    ip = [NSString stringWithUTF8String:buff];
                    break;
                }
            }
            tempAddr = tempAddr->ifa_next;
        }
    }
    
    freeifaddrs(interfaces);
    
    return ip;
}

+ (NSString *)getCellularIPv6Address {
    NSString *ip;
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *tempAddr = NULL;
    int success = 0;
    
    success = getifaddrs(&interfaces);
    
    if (success == 0) {
        tempAddr = interfaces;
        
        while (tempAddr != NULL) {
            if (tempAddr->ifa_addr->sa_family == AF_INET6) {    // IPv6
                if ([[NSString stringWithUTF8String:tempAddr->ifa_name] isEqualToString:@"pdp_ip0"]) {  // Cellular
                    char buff[256];
                    memset(buff, 0, sizeof(buff));
                    inet_ntop(AF_INET6, &((struct sockaddr_in6 *) tempAddr->ifa_addr)->sin6_addr, buff, sizeof(buff));
                    ip = [NSString stringWithUTF8String:buff];
                    break;
                }
            }
            tempAddr = tempAddr->ifa_next;
        }
    }
    
    freeifaddrs(interfaces);
    
    return ip;
}

+ (NSString *)getWiFiIPv4Address {
    NSString *ip;
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *tempAddr = NULL;
    int success = 0;
    
    success = getifaddrs(&interfaces);
    
    if (success == 0) {
        tempAddr = interfaces;
        
        while (tempAddr != NULL) {
            if (tempAddr->ifa_addr->sa_family == AF_INET) { // IPv4
                if ([[NSString stringWithUTF8String:tempAddr->ifa_name] isEqualToString:@"en0"]) {  // Wi-Fi
                    char buff[256];
                    memset(buff, 0, sizeof(buff));
                    inet_ntop(AF_INET, &((struct sockaddr_in *) tempAddr->ifa_addr)->sin_addr, buff, sizeof(buff));
                    ip = [NSString stringWithUTF8String:buff];
                    break;
                }
            }
            tempAddr = tempAddr->ifa_next;
        }
    }
    
    freeifaddrs(interfaces);
    
    return ip;
}

+ (NSString *)getWiFiIPv6Address {
    NSString *ip;
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *tempAddr = NULL;
    int success = 0;
    
    success = getifaddrs(&interfaces);
    
    if (success == 0) {
        tempAddr = interfaces;
        
        while (tempAddr != NULL) {
            if (tempAddr->ifa_addr->sa_family == AF_INET6) {    // IPv6
                if ([[NSString stringWithUTF8String:tempAddr->ifa_name] isEqualToString:@"en0"]) {  // Wi-Fi
                    char buff[256];
                    memset(buff, 0, sizeof(buff));
                    inet_ntop(AF_INET6, &((struct sockaddr_in6 *) tempAddr->ifa_addr)->sin6_addr, buff, sizeof(buff));
                    ip = [NSString stringWithUTF8String:buff];
                    break;
                }
            }
            tempAddr = tempAddr->ifa_next;
        }
    }
    
    freeifaddrs(interfaces);
    
    return ip;
}

@end