[Android] Fix some System.Net tests (#71385)

* Implement IncludeNetworkSecurityConfig

* Use IncludeNetworkSecurityConfig

* Fix tests

* Remove active issue attributes

* Rename certificate file

* Revert unnecessary changes

* TMP: re-throw caught exception to reveal more information in logs

* Revert "TMP: re-throw caught exception to reveal more information in logs"

This reverts commit 039d051d6ac60c1c3f1baf37b0c06872f87cac84.

* TMP: add and update res folders until they are merged into runtime-assets

* Fix System.Net.Requests tests

* Re-enable System.Net.Http functional tests

* Try fixing failing test

* Skip failing test

* Add missing using

* Remove temporary test data

* Relax exception type assertion for Android

* Code cleanup

* Fix test failures in System.Net.WebSockets.Client.Tests

* Remove active issue attribute

* Remove most explicit usages of the server certificate custom validation callback in tests

* Fix several tests

* Remove weird condition

* Code clean-up

* Remove unrelated active issue attributes

* Turn ActiveIssue attributes into permanent SkipOnPlatform

* Update explanation for SkipOnPlatform

* Revert partial fix and keep active issue

* Keep active issue for android x64 and x86

* Remove invalid attribute

* Fix test on Browser

* Allow all certificates by default

* Fix build

* Fix http client handler factory on Browser

* Skip failing test

* Fix net48 build

* Revert unintentional change in WinHttpHandler tests

* Avoid using unsupported property on Browser

* Remove unnecessary default value

* Avoid using unsupported property on Browser

3 files changed, 33 insertions, 2 deletions

diff --git a/src/tasks/AndroidAppBuilder/AndroidAppBuilder.cs b/src/tasks/AndroidAppBuilder/AndroidAppBuilder.cs
index b2ae7276fe9..66eef2cd542 100644
--- a/src/tasks/AndroidAppBuilder/AndroidAppBuilder.cs
+++ b/src/tasks/AndroidAppBuilder/AndroidAppBuilder.cs
@@ -80,6 +80,8 @@ public class AndroidAppBuilderTask : Task
     /// </summary>
     public string? NativeMainSource { get; set; }
 
+    public bool IncludeNetworkSecurityConfig { get; set; }
+
     public string? KeyStorePath { get; set; }
 
     public bool ForceInterpreter { get; set; }
@@ -105,6 +107,7 @@ public class AndroidAppBuilderTask : Task
         apkBuilder.BuildToolsVersion = BuildToolsVersion;
         apkBuilder.StripDebugSymbols = StripDebugSymbols;
         apkBuilder.NativeMainSource = NativeMainSource;
+        apkBuilder.IncludeNetworkSecurityConfig = IncludeNetworkSecurityConfig;
         apkBuilder.KeyStorePath = KeyStorePath;
         apkBuilder.ForceInterpreter = ForceInterpreter;
         apkBuilder.ForceAOT = ForceAOT;
diff --git a/src/tasks/AndroidAppBuilder/ApkBuilder.cs b/src/tasks/AndroidAppBuilder/ApkBuilder.cs
index 9ed098ac55a..11333b29e39 100644
--- a/src/tasks/AndroidAppBuilder/ApkBuilder.cs
+++ b/src/tasks/AndroidAppBuilder/ApkBuilder.cs
@@ -24,6 +24,7 @@ public class ApkBuilder
     public string OutputDir { get; set; } = ""!;
     public bool StripDebugSymbols { get; set; }
     public string? NativeMainSource { get; set; }
+    public bool IncludeNetworkSecurityConfig { get; set; }
     public string? KeyStorePath { get; set; }
     public bool ForceInterpreter { get; set; }
     public bool ForceAOT { get; set; }
@@ -57,6 +58,12 @@ public class ApkBuilder
             throw new ArgumentException($"MainLibraryFileName='{mainLibraryFileName}' was not found in AppDir='{AppDir}'");
         }
 
+        var networkSecurityConfigFilePath = Path.Combine(AppDir, "res", "xml", "network_security_config.xml");
+        if (IncludeNetworkSecurityConfig && !File.Exists(networkSecurityConfigFilePath))
+        {
+            throw new ArgumentException($"IncludeNetworkSecurityConfig is set but the file '{networkSecurityConfigFilePath}' was not found");
+        }
+
         if (string.IsNullOrEmpty(abi))
         {
             throw new ArgumentException("abi should not be empty (e.g. x86, x86_64, armeabi-v7a or arm64-v8a");
@@ -172,6 +179,7 @@ public class ApkBuilder
         Directory.CreateDirectory(Path.Combine(OutputDir, "obj"));
         Directory.CreateDirectory(Path.Combine(OutputDir, "assets-tozip"));
         Directory.CreateDirectory(Path.Combine(OutputDir, "assets"));
+        Directory.CreateDirectory(Path.Combine(OutputDir, "res"));
 
         var extensionsToIgnore = new List<string> { ".so", ".a", ".gz" };
         if (StripDebugSymbols)
@@ -183,6 +191,7 @@ public class ApkBuilder
         // Copy sourceDir to OutputDir/assets-tozip (ignore native files)
         // these files then will be zipped and copied to apk/assets/assets.zip
         var assetsToZipDirectory = Path.Combine(OutputDir, "assets-tozip");
+
         Utils.DirectoryCopy(AppDir, assetsToZipDirectory, file =>
         {
             string fileName = Path.GetFileName(file);
@@ -199,9 +208,20 @@ public class ApkBuilder
                 // aapt complains on such files
                 return false;
             }
+            if (file.Contains("/res/"))
+            {
+                // exclude everything in the `res` folder
+                return false;
+            }
             return true;
         });
 
+        // copy the res directory as is
+        if (Directory.Exists(Path.Combine(AppDir, "res")))
+        {
+            Utils.DirectoryCopy(Path.Combine(AppDir, "res"), Path.Combine(OutputDir, "res"));
+        }
+
         // add AOT .so libraries
         foreach (var aotlib in aotLibraryFiles)
         {
@@ -373,6 +393,11 @@ public class ApkBuilder
         if (!string.IsNullOrEmpty(NativeMainSource))
             File.Copy(NativeMainSource, javaActivityPath, true);
 
+        string networkSecurityConfigAttribute =
+            IncludeNetworkSecurityConfig
+                ? "a:networkSecurityConfig=\"@xml/network_security_config\""
+                : string.Empty;
+
         string envVariables = "";
         foreach (ITaskItem item in EnvironmentVariables)
         {
@@ -390,6 +415,7 @@ public class ApkBuilder
         File.WriteAllText(Path.Combine(OutputDir, "AndroidManifest.xml"),
             Utils.GetEmbeddedResource("AndroidManifest.xml")
                 .Replace("%PackageName%", packageId)
+                .Replace("%NetworkSecurityConfig%", networkSecurityConfigAttribute)
                 .Replace("%MinSdkLevel%", MinApiLevel));
 
         string javaCompilerArgs = $"-d obj -classpath src -bootclasspath {androidJar} -source 1.8 -target 1.8 ";
@@ -414,7 +440,8 @@ public class ApkBuilder
 
         string debugModeArg = StripDebugSymbols ? string.Empty : "--debug-mode";
         string apkFile = Path.Combine(OutputDir, "bin", $"{ProjectName}.unaligned.apk");
-        Utils.RunProcess(logger, aapt, $"package -f -m -F {apkFile} -A assets -M AndroidManifest.xml -I {androidJar} {debugModeArg}", workingDir: OutputDir);
+        string resources = IncludeNetworkSecurityConfig ? "-S res" : string.Empty;
+        Utils.RunProcess(logger, aapt, $"package -f -m -F {apkFile} -A assets {resources} -M AndroidManifest.xml -I {androidJar} {debugModeArg}", workingDir: OutputDir);
 
         var dynamicLibs = new List<string>();
         dynamicLibs.Add(Path.Combine(OutputDir, "monodroid", "libmonodroid.so"));
diff --git a/src/tasks/AndroidAppBuilder/Templates/AndroidManifest.xml b/src/tasks/AndroidAppBuilder/Templates/AndroidManifest.xml
index 9d28b5efbdf..befd2e446a6 100644
--- a/src/tasks/AndroidAppBuilder/Templates/AndroidManifest.xml
+++ b/src/tasks/AndroidAppBuilder/Templates/AndroidManifest.xml
@@ -7,7 +7,8 @@
   <uses-permission a:name="android.permission.INTERNET"/>
   <uses-permission a:name="android.permission.READ_EXTERNAL_STORAGE"/>
   <uses-permission a:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
-  <application a:label="%PackageName%" 
+  <application a:label="%PackageName%"
+               %NetworkSecurityConfig%
                a:largeHeap="true">
     <activity a:name="net.dot.MainActivity" a:exported="true">
       <intent-filter>