Model for an IP Address range

Signed-off-by: Roopesh Chander <roop@roopc.net>

1 files changed, 54 insertions, 0 deletions

diff --git a/WireGuard/WireGuard/Model/IPAddressRange.swift b/WireGuard/WireGuard/Model/IPAddressRange.swift
new file mode 100644
index 0000000..4498b58
--- /dev/null
+++ b/WireGuard/WireGuard/Model/IPAddressRange.swift
@@ -0,0 +1,54 @@
+//
+//  IPAddressRange.swift
+//  WireGuard
+//
+//  Created by Roopesh Chander on 13/10/18.
+//  Copyright © 2018 WireGuard LLC. All rights reserved.
+//
+
+import Foundation
+import Network
+
+@available(OSX 10.14, iOS 12.0, *)
+struct IPAddressRange {
+    let address: IPAddress
+    var networkPrefixLength: UInt8
+}
+
+@available(OSX 10.14, iOS 12.0, *)
+extension IPAddressRange: Codable {
+    public func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        let addressDataLength: Int
+        if address is IPv4Address {
+            addressDataLength = 4
+        } else if address is IPv6Address {
+            addressDataLength = 16
+        } else {
+            fatalError()
+        }
+        var data = Data(capacity: addressDataLength + 1)
+        data.append(address.rawValue)
+        data.append(networkPrefixLength)
+        try container.encode(data)
+    }
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        var data = try container.decode(Data.self)
+        networkPrefixLength = data.removeLast()
+        let ipAddressFromData: IPAddress? = {
+            switch (data.count) {
+            case 4: return IPv4Address(data)
+            case 16: return IPv6Address(data)
+            default: return nil
+            }
+        }()
+        guard let ipAddress = ipAddressFromData else {
+            throw DecodingError.invalidData
+        }
+        address = ipAddress
+    }
+    enum DecodingError: Error {
+        case invalidData
+    }
+}