From b8330c08b59ae0af7a85ded8449f4a38c681a8e1 Mon Sep 17 00:00:00 2001
From: digaus <di.gaus@gmx.de>
Date: Fri, 17 Jan 2020 19:32:42 +0100
Subject: [PATCH 1/2] Prevent iOS crash on NetService.dictionary call

Decode the TXT record as a string dictionary, or [:] if the data is malformed: https://stackoverflow.com/a/52220739
---
 src/ios/ZeroConf.swift | 38 ++++++++++++++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/src/ios/ZeroConf.swift b/src/ios/ZeroConf.swift
index 573e85c..318010e 100644
--- a/src/ios/ZeroConf.swift
+++ b/src/ios/ZeroConf.swift
@@ -1,3 +1,4 @@
+import Cordova
 import Foundation
 
 @objc(ZeroConf) public class ZeroConf : CDVPlugin  {
@@ -395,10 +396,7 @@ import Foundation
 
         var txtRecord: [String: String] = [:]
         if let txtRecordData = netService.txtRecordData() {
-            let dict = NetService.dictionary(fromTXTRecord: txtRecordData)
-            for (key, data) in dict {
-                txtRecord[key] = String(data: data, encoding:String.Encoding.utf8)
-            }
+            txtRecord = dictionary(fromTXTRecord: txtRecordData)
         }
 
         var hostName:String = ""
@@ -436,4 +434,36 @@ import Foundation
         return nil
     }
 
+    fileprivate static func dictionary(fromTXTRecord txtData: Data) -> [String: String] {
+
+        var result = [String: String]()
+        var data = txtData
+
+        while !data.isEmpty {
+            // The first byte of each record is its length, so prefix that much data
+            let recordLength = Int(data.removeFirst())
+            guard data.count >= recordLength else { return [:] }
+            let recordData = data[..<(data.startIndex + recordLength)]
+            data = data.dropFirst(recordLength)
+
+            guard let record = String(bytes: recordData, encoding: .utf8) else { return [:] }
+            // The format of the entry is "key=value"
+            // (According to the reference implementation, = is optional if there is no value,
+            // and any equals signs after the first are part of the value.)
+            // `ommittingEmptySubsequences` is necessary otherwise an empty string will crash the next line
+            let keyValue = record.split(separator: "=", maxSplits: 1, omittingEmptySubsequences: false)
+            let key = String(keyValue[0])
+            // If there's no value, make the value the empty string
+            switch keyValue.count {
+            case 1:
+                result[key] = ""
+            case 2:
+                result[key] = String(keyValue[1])
+            default:
+                fatalError()
+            }
+        }
+
+        return result
+    }
 }

From 3f00f8f007c4fe122d11ea43454f8c6ba0be2f77 Mon Sep 17 00:00:00 2001
From: digaus <di.gaus@gmx.de>
Date: Fri, 17 Jan 2020 19:36:00 +0100
Subject: [PATCH 2/2] Update ZeroConf.swift

Remove import
---
 src/ios/ZeroConf.swift | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/ios/ZeroConf.swift b/src/ios/ZeroConf.swift
index 318010e..088ee5c 100644
--- a/src/ios/ZeroConf.swift
+++ b/src/ios/ZeroConf.swift
@@ -1,4 +1,3 @@
-import Cordova
 import Foundation
 
 @objc(ZeroConf) public class ZeroConf : CDVPlugin  {