How to get local and subnet mask ip address in swift - ios

Question

I need to get the local IP address and subnet mask using Swift code.
Please help me in this. I have some code working in Objective-C. How to get the equivalent code in Swift??
Below I have added Objective-C code:
+(NSDictionary *)getLocalIPAddress{
NSDictionary *dictIPDetails;
NSString *address = #"error";
NSString *netmask = #"error";
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)
{
temp_addr = interfaces;
while(temp_addr != NULL)
{
// check if interface is en0 which is the wifi connection on the iPhone
if(temp_addr->ifa_addr->sa_family == AF_INET)
{
if([#(temp_addr->ifa_name) isEqualToString:#"en0"])
{
address = #(inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr));
netmask = #(inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_netmask)->sin_addr));
dictIPDetails = #{LOCAL_IP_ADDR:address,SUBNET_MASK:netmask};
}
}
temp_addr = temp_addr->ifa_next;
}
}
freeifaddrs(interfaces);
return dictIPDetails;
}

Answer 1

I have modified the answer from here to include netmask along with ip.
With the code below you can do something like this:
let ip = getIFAddresses().last!.ip
let netmask = getIFAddresses().last!.netmask
Hope this helps.
struct NetInfo {
let ip: String
let netmask: String
}
// Get the local ip addresses used by this node
func getIFAddresses() -> [NetInfo] {
var addresses = [NetInfo]()
// Get list of all interfaces on the local machine:
var ifaddr : UnsafeMutablePointer<ifaddrs> = nil
if getifaddrs(&ifaddr) == 0 {
// For each interface ...
for (var ptr = ifaddr; ptr != nil; ptr = ptr.memory.ifa_next) {
let flags = Int32(ptr.memory.ifa_flags)
var addr = ptr.memory.ifa_addr.memory
// Check for running IPv4, IPv6 interfaces. Skip the loopback interface.
if (flags & (IFF_UP|IFF_RUNNING|IFF_LOOPBACK)) == (IFF_UP|IFF_RUNNING) {
if addr.sa_family == UInt8(AF_INET) || addr.sa_family == UInt8(AF_INET6) {
// Convert interface address to a human readable string:
var hostname = [CChar](count: Int(NI_MAXHOST), repeatedValue: 0)
if (getnameinfo(&addr, socklen_t(addr.sa_len), &hostname, socklen_t(hostname.count),
nil, socklen_t(0), NI_NUMERICHOST) == 0) {
if let address = String.fromCString(hostname) {
var net = ptr.memory.ifa_netmask.memory
var netmaskName = [CChar](count: Int(NI_MAXHOST), repeatedValue: 0)
getnameinfo(&net, socklen_t(net.sa_len), &netmaskName, socklen_t(netmaskName.count),
nil, socklen_t(0), NI_NUMERICHOST) == 0
if let netmask = String.fromCString(netmaskName) {
addresses.append(NetInfo(ip: address, netmask: netmask))
}
}
}
}
}
}
freeifaddrs(ifaddr)
}
return addresses
}
If you need more bells and whistles I have this version of NetInfo which will calculate your network and broadcast addresses as well.
struct NetInfo {
// IP Address
let ip: String
// Netmask Address
let netmask: String
// CIDR: Classless Inter-Domain Routing
var cidr: Int {
var cidr = 0
for number in binaryRepresentation(netmask) {
let numberOfOnes = number.componentsSeparatedByString("1").count - 1
cidr += numberOfOnes
}
return cidr
}
// Network Address
var network: String {
return bitwise(&, net1: ip, net2: netmask)
}
// Broadcast Address
var broadcast: String {
let inverted_netmask = bitwise(~, net1: netmask)
let broadcast = bitwise(|, net1: network, net2: inverted_netmask)
return broadcast
}
private func binaryRepresentation(s: String) -> [String] {
var result: [String] = []
for numbers in (split(s) {$0 == "."}) {
if let intNumber = numbers.toInt() {
if let binary = String(intNumber, radix: 2).toInt() {
result.append(NSString(format: "%08d", binary) as String)
}
}
}
return result
}
private func bitwise(op: (UInt8,UInt8) -> UInt8, net1: String, net2: String) -> String {
let net1numbers = toInts(net1)
let net2numbers = toInts(net2)
var result = ""
for i in 0..<net1numbers.count {
result += "\(op(net1numbers[i],net2numbers[i]))"
if i < (net1numbers.count-1) {
result += "."
}
}
return result
}
private func bitwise(op: UInt8 -> UInt8, net1: String) -> String {
let net1numbers = toInts(net1)
var result = ""
for i in 0..<net1numbers.count {
result += "\(op(net1numbers[i]))"
if i < (net1numbers.count-1) {
result += "."
}
}
return result
}
private func toInts(networkString: String) -> [UInt8] {
return (split(networkString){$0 == "."}).map{UInt8($0.toInt()!)}
}
}

Answer 2

changed the code so it works with swift 3:
struct NetInfo {
let ip: String
let netmask: String
}
// Get the local ip addresses used by this node
class func getIFAddresses() -> [NetInfo] {
var addresses = [NetInfo]()
// Get list of all interfaces on the local machine:
var ifaddr : UnsafeMutablePointer<ifaddrs>? = nil
if getifaddrs(&ifaddr) == 0 {
var ptr = ifaddr;
while ptr != nil {
let flags = Int32((ptr?.pointee.ifa_flags)!)
var addr = ptr?.pointee.ifa_addr.pointee
// Check for running IPv4, IPv6 interfaces. Skip the loopback interface.
if (flags & (IFF_UP|IFF_RUNNING|IFF_LOOPBACK)) == (IFF_UP|IFF_RUNNING) {
if addr?.sa_family == UInt8(AF_INET) || addr?.sa_family == UInt8(AF_INET6) {
// Convert interface address to a human readable string:
var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))
if (getnameinfo(&addr!, socklen_t((addr?.sa_len)!), &hostname, socklen_t(hostname.count),
nil, socklen_t(0), NI_NUMERICHOST) == 0) {
if let address = String.init(validatingUTF8:hostname) {
var net = ptr?.pointee.ifa_netmask.pointee
var netmaskName = [CChar](repeating: 0, count: Int(NI_MAXHOST))
getnameinfo(&net!, socklen_t((net?.sa_len)!), &netmaskName, socklen_t(netmaskName.count),
nil, socklen_t(0), NI_NUMERICHOST)// == 0
if let netmask = String.init(validatingUTF8:netmaskName) {
addresses.append(NetInfo(ip: address, netmask: netmask))
}
}
}
}
}
ptr = ptr?.pointee.ifa_next
}
freeifaddrs(ifaddr)
}
return addresses
}

Answer 3

Here's Mellson's extended NetInfo re-written for Swift 2 (Hope it save's someone else the time to work it out)
struct NetInfo {
// IP Address
let ip: String
// Netmask Address
let netmask: String
// CIDR: Classless Inter-Domain Routing
var cidr: Int {
var cidr = 0
for number in binaryRepresentation(netmask) {
let numberOfOnes = number.componentsSeparatedByString("1").count - 1
cidr += numberOfOnes
}
return cidr
}
// Network Address
var network: String {
return bitwise(&, net1: ip, net2: netmask)
}
// Broadcast Address
var broadcast: String {
let inverted_netmask = bitwise(~, net1: netmask)
let broadcast = bitwise(|, net1: network, net2: inverted_netmask)
return broadcast
}
private func binaryRepresentation(s: String) -> [String] {
var result: [String] = []
for numbers in (s.characters.split {$0 == "."}) {
if let intNumber = Int(String(numbers)) {
if let binary = Int(String(intNumber, radix: 2)) {
result.append(NSString(format: "%08d", binary) as String)
}
}
}
return result
}
private func bitwise(op: (UInt8,UInt8) -> UInt8, net1: String, net2: String) -> String {
let net1numbers = toInts(net1)
let net2numbers = toInts(net2)
var result = ""
for i in 0..<net1numbers.count {
result += "\(op(net1numbers[i],net2numbers[i]))"
if i < (net1numbers.count-1) {
result += "."
}
}
return result
}
private func bitwise(op: UInt8 -> UInt8, net1: String) -> String {
let net1numbers = toInts(net1)
var result = ""
for i in 0..<net1numbers.count {
result += "\(op(net1numbers[i]))"
if i < (net1numbers.count-1) {
result += "."
}
}
return result
}
private func toInts(networkString: String) -> [UInt8] {
return (networkString.characters.split {$0 == "."}).map{UInt8(String($0))!}
}
}

Answer 4

let theOutput = Pipe()
func shell(Path:String ,args: String...) -> Int32 {
let task = Process()
task.launchPath = Path
task.arguments = args
task.standardOutput = theOutput
task.standardError = theOutput
task.launch()
task.waitUntilExit()
return task.terminationStatus
}
shell(Path:"/usr/sbin/arp",args: "-a")
let theTaskData = theOutput.fileHandleForReading.readDataToEndOfFile()
let stringResult = String(data: theTaskData, encoding: .utf8)
print(stringResult!)