Add Validator for Endpoints.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/Shared/Validators.swift b/Shared/Validators.swift
new file mode 100644
index 0000000..b215343
--- /dev/null
+++ b/Shared/Validators.swift
@@ -0,0 +1,71 @@
+//
+//  IPValidator.swift
+//  WireGuard
+//
+//  Created by Jeroen Leenarts on 15-08-18.
+//  Copyright © 2018 WireGuard. All rights reserved.
+//
+
+import Foundation
+
+enum AddressType {
+    case IPv6, IPv4, other
+}
+
+public enum EndpointValidationError: Error {
+    case noIpAndPort(String)
+    case invalidIP(String)
+    case invalidPort(String)
+
+    var localizedDescription: String {
+        switch self {
+        case .noIpAndPort:
+            return NSLocalizedString("EndpointValidationError.noIpAndPort", comment: "Error message for malformed endpoint.")
+        case .invalidIP:
+            return NSLocalizedString("EndpointValidationError.invalidIP", comment: "Error message for invalid endpoint ip.")
+        case .invalidPort:
+            return NSLocalizedString("EndpointValidationError.invalidPort", comment: "Error message invalid endpoint port.")
+        }
+    }
+}
+struct Endpoint {
+    var ipAddress: String
+    var port: Int32
+    var addressType: AddressType
+
+    init?(endpointString: String) throws {
+        let parts = endpointString.split(separator: ":")
+        guard parts.count == 2 else {
+            throw EndpointValidationError.noIpAndPort(endpointString)
+        }
+        guard let port = Int32(parts[1]), port > 0 else {
+            throw EndpointValidationError.invalidPort(String(parts[1]))
+        }
+
+        ipAddress = String(parts[0])
+        let addressType = validateIpAddress(ipToValidate: ipAddress)
+        guard addressType == .IPv4 || addressType == .IPv6 else {
+            throw EndpointValidationError.invalidIP(ipAddress)
+        }
+        self.addressType = addressType
+
+        self.port = port
+    }
+}
+
+func validateIpAddress(ipToValidate: String) -> AddressType {
+
+    var sin = sockaddr_in()
+    if ipToValidate.withCString({ cstring in inet_pton(AF_INET, cstring, &sin.sin_addr) }) == 1 {
+        // IPv4 peer.
+        return .IPv4
+    }
+
+    var sin6 = sockaddr_in6()
+    if ipToValidate.withCString({ cstring in inet_pton(AF_INET6, cstring, &sin6.sin6_addr) }) == 1 {
+        // IPv6 peer.
+        return .IPv6
+    }
+
+    return .other
+}