From 757535359761e05a57e5cfa1f64cc2ba88336e05 Mon Sep 17 00:00:00 2001
From: Matt Nadareski <mnadareski@outlook.com>
Date: Sat, 16 Sep 2023 21:25:50 -0400
Subject: [PATCH] Add nullability to matching library, fix warnings

---
 .../BinaryObjectScanner.Matching.csproj       |  4 +
 BinaryObjectScanner.Matching/ContentMatch.cs  | 66 ++++++++-----
 .../ContentMatchSet.cs                        | 58 +++++++++--
 BinaryObjectScanner.Matching/Extensions.cs    | 16 ++++
 BinaryObjectScanner.Matching/IMatch.cs        |  4 +
 BinaryObjectScanner.Matching/MatchSet.cs      |  8 ++
 BinaryObjectScanner.Matching/MatchUtil.cs     | 96 +++++++++++--------
 BinaryObjectScanner.Matching/PathMatch.cs     | 40 ++++++--
 BinaryObjectScanner.Matching/PathMatchSet.cs  | 44 ++++++++-
 9 files changed, 251 insertions(+), 85 deletions(-)

diff --git a/BinaryObjectScanner.Matching/BinaryObjectScanner.Matching.csproj b/BinaryObjectScanner.Matching/BinaryObjectScanner.Matching.csproj
index deb03650..8749a9d2 100644
--- a/BinaryObjectScanner.Matching/BinaryObjectScanner.Matching.csproj
+++ b/BinaryObjectScanner.Matching/BinaryObjectScanner.Matching.csproj
@@ -19,4 +19,8 @@
     <IncludeSymbols>true</IncludeSymbols>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetFramework)'!='net48'">
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
 </Project>
diff --git a/BinaryObjectScanner.Matching/ContentMatch.cs b/BinaryObjectScanner.Matching/ContentMatch.cs
index ecde1e72..0443c36f 100644
--- a/BinaryObjectScanner.Matching/ContentMatch.cs
+++ b/BinaryObjectScanner.Matching/ContentMatch.cs
@@ -10,17 +10,25 @@ namespace BinaryObjectScanner.Matching
         /// <summary>
         /// Content to match
         /// </summary>
+#if NET48
         public byte?[] Needle { get; set; }
+#else
+        public byte?[]? Needle { get; init; }
+#endif
 
         /// <summary>
         /// Starting index for matching
         /// </summary>
-        public int Start { get; set; }
+        public int Start { get; internal set; }
 
         /// <summary>
         /// Ending index for matching
         /// </summary>
-        public int End { get; set; }
+#if NET48
+        public int End { get; private set; }
+#else
+        public int End { get; init; }
+#endif
 
         /// <summary>
         /// Constructor
@@ -28,11 +36,15 @@ namespace BinaryObjectScanner.Matching
         /// <param name="needle">Byte array representing the search</param>
         /// <param name="start">Optional starting index</param>
         /// <param name="end">Optional ending index</param>
+#if NET48
         public ContentMatch(byte?[] needle, int start = -1, int end = -1)
+#else
+        public ContentMatch(byte?[]? needle, int start = -1, int end = -1)
+#endif
         {
-            Needle = needle;
-            Start = start;
-            End = end;
+            this.Needle = needle;
+            this.Start = start;
+            this.End = end;
         }
 
         #region Array Matching
@@ -46,22 +58,22 @@ namespace BinaryObjectScanner.Matching
         public (bool success, int position) Match(byte[] stack, bool reverse = false)
         {
             // If either array is null or empty, we can't do anything
-            if (stack == null || stack.Length == 0 || Needle == null || Needle.Length == 0)
+            if (stack == null || stack.Length == 0 || this.Needle == null || this.Needle.Length == 0)
                 return (false, -1);
 
             // If the needle array is larger than the stack array, it can't be contained within
-            if (Needle.Length > stack.Length)
+            if (this.Needle.Length > stack.Length)
                 return (false, -1);
 
             // Set the default start and end values
-            int start = Start;
-            int end = End;
+            int start = this.Start;
+            int end = this.End;
 
             // If start or end are not set properly, set them to defaults
             if (start < 0)
                 start = 0;
             if (end < 0)
-                end = stack.Length - Needle.Length;
+                end = stack.Length - this.Needle.Length;
 
             for (int i = reverse ? end : start; reverse ? i > start : i < end; i += reverse ? -1 : 1)
             {
@@ -85,21 +97,25 @@ namespace BinaryObjectScanner.Matching
         /// <returns>True if the needle matches the stack at a given index</returns>
         private bool EqualAt(byte[] stack, int index)
         {
+            // If the needle is invalid, we can't do anything
+            if (this.Needle == null)
+                return false;
+
             // If the index is invalid, we can't do anything
             if (index < 0)
                 return false;
 
             // If we're too close to the end of the stack, return false
-            if (Needle.Length > stack.Length - index)
+            if (this.Needle.Length > stack.Length - index)
                 return false;
 
             // Loop through and check the value
-            for (int i = 0; i < Needle.Length; i++)
+            for (int i = 0; i < this.Needle.Length; i++)
             {
                 // A null value is a wildcard
-                if (Needle[i] == null)
+                if (this.Needle[i] == null)
                     continue;
-                else if (stack[i + index] != Needle[i])
+                else if (stack[i + index] != this.Needle[i])
                     return false;
             }
 
@@ -119,22 +135,22 @@ namespace BinaryObjectScanner.Matching
         public (bool success, int position) Match(Stream stack, bool reverse = false)
         {
             // If either array is null or empty, we can't do anything
-            if (stack == null || stack.Length == 0 || Needle == null || Needle.Length == 0)
+            if (stack == null || stack.Length == 0 || this.Needle == null || this.Needle.Length == 0)
                 return (false, -1);
 
             // If the needle array is larger than the stack array, it can't be contained within
-            if (Needle.Length > stack.Length)
+            if (this.Needle.Length > stack.Length)
                 return (false, -1);
 
             // Set the default start and end values
-            int start = Start;
-            int end = End;
+            int start = this.Start;
+            int end = this.End;
 
             // If start or end are not set properly, set them to defaults
             if (start < 0)
                 start = 0;
             if (end < 0)
-                end = (int)(stack.Length - Needle.Length);
+                end = (int)(stack.Length - this.Needle.Length);
 
             for (int i = reverse ? end : start; reverse ? i > start : i < end; i += reverse ? -1 : 1)
             {
@@ -158,12 +174,16 @@ namespace BinaryObjectScanner.Matching
         /// <returns>True if the needle matches the stack at a given index</returns>
         private bool EqualAt(Stream stack, int index)
         {
+            // If the needle is invalid, we can't do anything
+            if (this.Needle == null)
+                return false;
+
             // If the index is invalid, we can't do anything
             if (index < 0)
                 return false;
 
             // If we're too close to the end of the stack, return false
-            if (Needle.Length > stack.Length - index)
+            if (this.Needle.Length > stack.Length - index)
                 return false;
 
             // Save the current position and move to the index
@@ -174,16 +194,16 @@ namespace BinaryObjectScanner.Matching
             bool matched = true;
 
             // Loop through and check the value
-            for (int i = 0; i < Needle.Length; i++)
+            for (int i = 0; i < this.Needle.Length; i++)
             {
                 byte stackValue = (byte)stack.ReadByte();
 
                 // A null value is a wildcard
-                if (Needle[i] == null)
+                if (this.Needle[i] == null)
                 {
                     continue;
                 }
-                else if (stackValue != Needle[i])
+                else if (stackValue != this.Needle[i])
                 {
                     matched = false;
                     break;
diff --git a/BinaryObjectScanner.Matching/ContentMatchSet.cs b/BinaryObjectScanner.Matching/ContentMatchSet.cs
index 4d5a9035..9dc68298 100644
--- a/BinaryObjectScanner.Matching/ContentMatchSet.cs
+++ b/BinaryObjectScanner.Matching/ContentMatchSet.cs
@@ -20,7 +20,11 @@ namespace BinaryObjectScanner.Matching
         /// to the protection name, or `null`, in which case it will cause
         /// the protection to be omitted.
         /// </remarks>
-        public Func<string, byte[], List<int>, string> GetArrayVersion { get; set; }
+#if NET48
+        public Func<string, byte[], List<int>, string> GetArrayVersion { get; private set; }
+#else
+        public Func<string, byte[], List<int>, string>? GetArrayVersion { get; init; }
+#endif
 
         /// <summary>
         /// Function to get a content version
@@ -32,7 +36,11 @@ namespace BinaryObjectScanner.Matching
         /// to the protection name, or `null`, in which case it will cause
         /// the protection to be omitted.
         /// </remarks>
-        public Func<string, Stream, List<int>, string> GetStreamVersion { get; set; }
+#if NET48
+        public Func<string, Stream, List<int>, string> GetStreamVersion { get; private set; }
+#else
+        public Func<string, Stream, List<int>, string>? GetStreamVersion { get; init; }
+#endif
 
         #region Generic Constructors
 
@@ -52,6 +60,7 @@ namespace BinaryObjectScanner.Matching
 
         #region Array Constructors
 
+#if NET48
         public ContentMatchSet(byte?[] needle, Func<string, byte[], List<int>, string> getArrayVersion, string protectionName)
             : this(new List<byte?[]> { needle }, getArrayVersion, protectionName) { }
 
@@ -67,11 +76,29 @@ namespace BinaryObjectScanner.Matching
             GetArrayVersion = getArrayVersion;
             ProtectionName = protectionName;
         }
+#else
+        public ContentMatchSet(byte?[] needle, Func<string, byte[], List<int>, string>? getArrayVersion, string protectionName)
+            : this(new List<byte?[]> { needle }, getArrayVersion, protectionName) { }
+
+        public ContentMatchSet(List<byte?[]> needles, Func<string, byte[], List<int>, string>? getArrayVersion, string protectionName)
+            : this(needles.Select(n => new ContentMatch(n)).ToList(), getArrayVersion, protectionName) { }
+
+        public ContentMatchSet(ContentMatch needle, Func<string, byte[], List<int>, string>? getArrayVersion, string protectionName)
+            : this(new List<ContentMatch>() { needle }, getArrayVersion, protectionName) { }
+
+        public ContentMatchSet(List<ContentMatch> needles, Func<string, byte[], List<int>, string>? getArrayVersion, string protectionName)
+        {
+            Matchers = needles;
+            GetArrayVersion = getArrayVersion;
+            ProtectionName = protectionName;
+        }
+#endif
 
         #endregion
 
         #region Stream Constructors
 
+#if NET48
         public ContentMatchSet(byte?[] needle, Func<string, Stream, List<int>, string> getStreamVersion, string protectionName)
             : this(new List<byte?[]> { needle }, getStreamVersion, protectionName) { }
 
@@ -87,6 +114,23 @@ namespace BinaryObjectScanner.Matching
             GetStreamVersion = getStreamVersion;
             ProtectionName = protectionName;
         }
+#else
+        public ContentMatchSet(byte?[] needle, Func<string, Stream, List<int>, string>? getStreamVersion, string protectionName)
+            : this(new List<byte?[]> { needle }, getStreamVersion, protectionName) { }
+
+        public ContentMatchSet(List<byte?[]> needles, Func<string, Stream, List<int>, string>? getStreamVersion, string protectionName)
+            : this(needles.Select(n => new ContentMatch(n)).ToList(), getStreamVersion, protectionName) { }
+
+        public ContentMatchSet(ContentMatch needle, Func<string, Stream, List<int>, string>? getStreamVersion, string protectionName)
+            : this(new List<ContentMatch>() { needle }, getStreamVersion, protectionName) { }
+
+        public ContentMatchSet(List<ContentMatch> needles, Func<string, Stream, List<int>, string>? getStreamVersion, string protectionName)
+        {
+            Matchers = needles;
+            GetStreamVersion = getStreamVersion;
+            ProtectionName = protectionName;
+        }
+#endif
 
         #endregion
 
@@ -96,7 +140,7 @@ namespace BinaryObjectScanner.Matching
         /// Determine whether all content matches pass
         /// </summary>
         /// <param name="stack">Array to search</param>
-        /// <returns>Tuple of passing status and matching positions</returns>        
+        /// <returns>Tuple of passing status and matching positions</returns>
         public (bool, List<int>) MatchesAll(byte[] stack)
         {
             // If no content matches are defined, we fail out
@@ -104,7 +148,7 @@ namespace BinaryObjectScanner.Matching
                 return (false, new List<int>());
 
             // Initialize the position list
-            List<int> positions = new List<int>();
+            var positions = new List<int>();
 
             // Loop through all content matches and make sure all pass
             foreach (var contentMatch in Matchers)
@@ -123,7 +167,7 @@ namespace BinaryObjectScanner.Matching
         /// Determine whether any content matches pass
         /// </summary>
         /// <param name="stack">Array to search</param>
-        /// <returns>Tuple of passing status and first matching position</returns>        
+        /// <returns>Tuple of passing status and first matching position</returns>
         public (bool, int) MatchesAny(byte[] stack)
         {
             // If no content matches are defined, we fail out
@@ -149,7 +193,7 @@ namespace BinaryObjectScanner.Matching
         /// Determine whether all content matches pass
         /// </summary>
         /// <param name="stack">Stream to search</param>
-        /// <returns>Tuple of passing status and matching positions</returns>        
+        /// <returns>Tuple of passing status and matching positions</returns>
         public (bool, List<int>) MatchesAll(Stream stack)
         {
             // If no content matches are defined, we fail out
@@ -176,7 +220,7 @@ namespace BinaryObjectScanner.Matching
         /// Determine whether any content matches pass
         /// </summary>
         /// <param name="stack">Stream to search</param>
-        /// <returns>Tuple of passing status and first matching position</returns>        
+        /// <returns>Tuple of passing status and first matching position</returns>
         public (bool, int) MatchesAny(Stream stack)
         {
             // If no content matches are defined, we fail out
diff --git a/BinaryObjectScanner.Matching/Extensions.cs b/BinaryObjectScanner.Matching/Extensions.cs
index a2b535d0..5c6c9e20 100644
--- a/BinaryObjectScanner.Matching/Extensions.cs
+++ b/BinaryObjectScanner.Matching/Extensions.cs
@@ -33,16 +33,28 @@ namespace BinaryObjectScanner.Matching
         /// <summary>
         /// Find the first position of one array in another, if possible
         /// </summary>
+#if NET48
         public static bool FirstPosition(this byte[] stack, byte[] needle, out int position, int start = 0, int end = -1)
         {
             byte?[] nullableNeedle = needle != null ? needle.Select(b => (byte?)b).ToArray() : null;
             return stack.FirstPosition(nullableNeedle, out position, start, end);
         }
+#else
+        public static bool FirstPosition(this byte[] stack, byte[]? needle, out int position, int start = 0, int end = -1)
+        {
+            byte?[]? nullableNeedle = needle != null ? needle.Select(b => (byte?)b).ToArray() : null;
+            return stack.FirstPosition(nullableNeedle, out position, start, end);
+        }
+#endif
 
         /// <summary>
         /// Find the first position of one array in another, if possible
         /// </summary>
+#if NET48
         public static bool FirstPosition(this byte[] stack, byte?[] needle, out int position, int start = 0, int end = -1)
+#else
+        public static bool FirstPosition(this byte[] stack, byte?[]? needle, out int position, int start = 0, int end = -1)
+#endif
         {
             var matcher = new ContentMatch(needle, start, end);
             (bool found, int foundPosition) = matcher.Match(stack, false);
@@ -53,7 +65,11 @@ namespace BinaryObjectScanner.Matching
         /// <summary>
         /// Find the last position of one array in another, if possible
         /// </summary>
+#if NET48
         public static bool LastPosition(this byte[] stack, byte?[] needle, out int position, int start = 0, int end = -1)
+#else
+        public static bool LastPosition(this byte[] stack, byte?[]? needle, out int position, int start = 0, int end = -1)
+#endif
         {
             var matcher = new ContentMatch(needle, start, end);
             (bool found, int foundPosition) = matcher.Match(stack, true);
diff --git a/BinaryObjectScanner.Matching/IMatch.cs b/BinaryObjectScanner.Matching/IMatch.cs
index 5f985a9b..615aac9a 100644
--- a/BinaryObjectScanner.Matching/IMatch.cs
+++ b/BinaryObjectScanner.Matching/IMatch.cs
@@ -2,6 +2,10 @@
 {
     public interface IMatch<T>
     {
+#if NET48
         T Needle { get; set; }
+#else
+        T? Needle { get; init; }
+#endif
     }
 }
diff --git a/BinaryObjectScanner.Matching/MatchSet.cs b/BinaryObjectScanner.Matching/MatchSet.cs
index 3216b404..4ab3d87f 100644
--- a/BinaryObjectScanner.Matching/MatchSet.cs
+++ b/BinaryObjectScanner.Matching/MatchSet.cs
@@ -10,11 +10,19 @@ namespace BinaryObjectScanner.Matching
         /// <summary>
         /// Set of all matchers
         /// </summary>
+#if NET48
         public IEnumerable<T> Matchers { get; set; }
+#else
+        public IEnumerable<T>? Matchers { get; set; }
+#endif
 
         /// <summary>
         /// Name of the protection to show
         /// </summary>
+#if NET48
         public string ProtectionName { get; set; }
+#else
+        public string? ProtectionName { get; set; }
+#endif
     }
 }
\ No newline at end of file
diff --git a/BinaryObjectScanner.Matching/MatchUtil.cs b/BinaryObjectScanner.Matching/MatchUtil.cs
index a2ff7645..aba1eeb3 100644
--- a/BinaryObjectScanner.Matching/MatchUtil.cs
+++ b/BinaryObjectScanner.Matching/MatchUtil.cs
@@ -20,11 +20,11 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of ContentMatchSets to be run on the file</param>
         /// <param name="includeDebug">True to include positional data, false otherwise</param>
         /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>
-        public static ConcurrentQueue<string> GetAllMatches(
-            string file,
-            byte[] stack,
-            IEnumerable<ContentMatchSet> matchers,
-            bool includeDebug = false)
+#if NET48
+        public static ConcurrentQueue<string> GetAllMatches(string file, byte[] stack, IEnumerable<ContentMatchSet> matchers, bool includeDebug = false)
+#else
+        public static ConcurrentQueue<string>? GetAllMatches(string file, byte[] stack, IEnumerable<ContentMatchSet>? matchers, bool includeDebug = false)
+#endif
         {
             return FindAllMatches(file, stack, matchers, includeDebug, false);
         }
@@ -37,16 +37,16 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of ContentMatchSets to be run on the file</param>
         /// <param name="includeDebug">True to include positional data, false otherwise</param>
         /// <returns>String representing the matched protection, null otherwise</returns>
-        public static string GetFirstMatch(
-            string file,
-            byte[] stack,
-            IEnumerable<ContentMatchSet> matchers,
-            bool includeDebug = false)
+#if NET48
+        public static string GetFirstMatch(string file, byte[] stack, IEnumerable<ContentMatchSet> matchers, bool includeDebug = false)
+#else
+        public static string? GetFirstMatch(string file, byte[] stack, IEnumerable<ContentMatchSet>? matchers, bool includeDebug = false)
+#endif
         {
             var contentMatches = FindAllMatches(file, stack, matchers, includeDebug, true);
             if (contentMatches == null || !contentMatches.Any())
                 return null;
-            
+
             return contentMatches.First();
         }
 
@@ -58,13 +58,12 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of ContentMatchSets to be run on the file</param>
         /// <param name="includeDebug">True to include positional data, false otherwise</param>
         /// <param name="stopAfterFirst">True to stop after the first match, false otherwise</param>
-        /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>        
-        private static ConcurrentQueue<string> FindAllMatches(
-            string file,
-            byte[] stack,
-            IEnumerable<ContentMatchSet> matchers,
-            bool includeDebug,
-            bool stopAfterFirst)
+        /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>
+#if NET48
+        private static ConcurrentQueue<string> FindAllMatches(string file, byte[] stack, IEnumerable<ContentMatchSet> matchers, bool includeDebug, bool stopAfterFirst)
+#else
+        private static ConcurrentQueue<string>? FindAllMatches(string file, byte[] stack, IEnumerable<ContentMatchSet>? matchers, bool includeDebug, bool stopAfterFirst)
+#endif
         {
             // If there's no mappings, we can't match
             if (matchers == null || !matchers.Any())
@@ -121,11 +120,11 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of ContentMatchSets to be run on the file</param>
         /// <param name="includeDebug">True to include positional data, false otherwise</param>
         /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>
-        public static ConcurrentQueue<string> GetAllMatches(
-            string file,
-            Stream stack,
-            IEnumerable<ContentMatchSet> matchers,
-            bool includeDebug = false)
+#if NET48
+        public static ConcurrentQueue<string> GetAllMatches(string file, Stream stack, IEnumerable<ContentMatchSet> matchers, bool includeDebug = false)
+#else
+        public static ConcurrentQueue<string>? GetAllMatches(string file, Stream stack, IEnumerable<ContentMatchSet>? matchers, bool includeDebug = false)
+#endif
         {
             return FindAllMatches(file, stack, matchers, includeDebug, false);
         }
@@ -138,11 +137,11 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of ContentMatchSets to be run on the file</param>
         /// <param name="includeDebug">True to include positional data, false otherwise</param>
         /// <returns>String representing the matched protection, null otherwise</returns>
-        public static string GetFirstMatch(
-            string file,
-            Stream stack,
-            IEnumerable<ContentMatchSet> matchers,
-            bool includeDebug = false)
+#if NET48
+        public static string GetFirstMatch(string file, Stream stack, IEnumerable<ContentMatchSet> matchers, bool includeDebug = false)
+#else
+        public static string? GetFirstMatch(string file, Stream stack, IEnumerable<ContentMatchSet>? matchers, bool includeDebug = false)
+#endif
         {
             var contentMatches = FindAllMatches(file, stack, matchers, includeDebug, true);
             if (contentMatches == null || !contentMatches.Any())
@@ -159,13 +158,12 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of ContentMatchSets to be run on the file</param>
         /// <param name="includeDebug">True to include positional data, false otherwise</param>
         /// <param name="stopAfterFirst">True to stop after the first match, false otherwise</param>
-        /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>        
-        private static ConcurrentQueue<string> FindAllMatches(
-            string file,
-            Stream stack,
-            IEnumerable<ContentMatchSet> matchers,
-            bool includeDebug,
-            bool stopAfterFirst)
+        /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>
+#if NET48
+        private static ConcurrentQueue<string> FindAllMatches(string file, Stream stack, IEnumerable<ContentMatchSet> matchers, bool includeDebug, bool stopAfterFirst)
+#else
+        private static ConcurrentQueue<string>? FindAllMatches(string file, Stream stack, IEnumerable<ContentMatchSet>? matchers, bool includeDebug, bool stopAfterFirst)
+#endif
         {
             // If there's no mappings, we can't match
             if (matchers == null || !matchers.Any())
@@ -245,12 +243,16 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of PathMatchSets to be run on the file</param>
         /// <param name="any">True if any path match is a success, false if all have to match</param>
         /// <returns>String representing the matched protection, null otherwise</returns>
+#if NET48
         public static string GetFirstMatch(string file, IEnumerable<PathMatchSet> matchers, bool any = false)
+#else
+        public static string? GetFirstMatch(string file, IEnumerable<PathMatchSet> matchers, bool any = false)
+#endif
         {
             var contentMatches = FindAllMatches(new List<string> { file }, matchers, any, true);
             if (contentMatches == null || !contentMatches.Any())
                 return null;
-            
+
             return contentMatches.First();
         }
 
@@ -261,12 +263,16 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of PathMatchSets to be run on the file</param>
         /// <param name="any">True if any path match is a success, false if all have to match</param>
         /// <returns>String representing the matched protection, null otherwise</returns>
+#if NET48
         public static string GetFirstMatch(IEnumerable<string> files, IEnumerable<PathMatchSet> matchers, bool any = false)
+#else
+        public static string? GetFirstMatch(IEnumerable<string> files, IEnumerable<PathMatchSet> matchers, bool any = false)
+#endif
         {
             var contentMatches = FindAllMatches(files, matchers, any, true);
             if (contentMatches == null || !contentMatches.Any())
                 return null;
-            
+
             return contentMatches.First();
         }
 
@@ -277,7 +283,7 @@ namespace BinaryObjectScanner.Matching
         /// <param name="matchers">Enumerable of PathMatchSets to be run on the file</param>
         /// <param name="any">True if any path match is a success, false if all have to match</param>
         /// <param name="stopAfterFirst">True to stop after the first match, false otherwise</param>
-        /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>        
+        /// <returns>List of strings representing the matched protections, null or empty otherwise</returns>
         private static ConcurrentQueue<string> FindAllMatches(IEnumerable<string> files, IEnumerable<PathMatchSet> matchers, bool any, bool stopAfterFirst)
         {
             // If there's no mappings, we can't match
@@ -292,10 +298,18 @@ namespace BinaryObjectScanner.Matching
             {
                 // Determine if the matcher passes
                 bool passes;
+#if NET48
                 string firstMatchedString;
+#else
+                string? firstMatchedString;
+#endif
                 if (any)
                 {
+#if NET48
                     (bool anyPasses, string matchedString) = matcher.MatchesAny(files);
+#else
+                    (bool anyPasses, string? matchedString) = matcher.MatchesAny(files);
+#endif
                     passes = anyPasses;
                     firstMatchedString = matchedString;
                 }
@@ -305,9 +319,9 @@ namespace BinaryObjectScanner.Matching
                     passes = allPasses;
                     firstMatchedString = matchedStrings.FirstOrDefault();
                 }
-                
+
                 // If we don't have a pass, just continue
-                if (!passes)
+                if (!passes || firstMatchedString == null)
                     continue;
 
                 // If we there is no version method, just return the protection name
@@ -334,7 +348,7 @@ namespace BinaryObjectScanner.Matching
 
             return matchedProtections;
         }
-    
+
         #endregion
     }
 }
\ No newline at end of file
diff --git a/BinaryObjectScanner.Matching/PathMatch.cs b/BinaryObjectScanner.Matching/PathMatch.cs
index 30d297d7..ac8f0e8a 100644
--- a/BinaryObjectScanner.Matching/PathMatch.cs
+++ b/BinaryObjectScanner.Matching/PathMatch.cs
@@ -11,17 +11,29 @@ namespace BinaryObjectScanner.Matching
         /// <summary>
         /// String to match
         /// </summary>
+#if NET48
         public string Needle { get; set; }
+#else
+        public string? Needle { get; init; }
+#endif
 
         /// <summary>
         /// Match exact casing instead of invariant
         /// </summary>
-        public bool MatchExact { get; set; }
+#if NET48
+        public bool MatchExact { get; private set; }
+#else
+        public bool MatchExact { get; init; }
+#endif
 
         /// <summary>
         /// Match that values end with the needle and not just contains
         /// </summary>
-        public bool UseEndsWith { get; set; }
+#if NET48
+        public bool UseEndsWith { get; private set; }
+#else
+        public bool UseEndsWith { get; init; }
+#endif
 
         /// <summary>
         /// Constructor
@@ -29,11 +41,15 @@ namespace BinaryObjectScanner.Matching
         /// <param name="needle">String representing the search</param>
         /// <param name="matchExact">True to match exact casing, false otherwise</param>
         /// <param name="useEndsWith">True to match the end only, false for all contents</param>
+#if NET48
         public PathMatch(string needle, bool matchExact = false, bool useEndsWith = false)
+#else
+        public PathMatch(string? needle, bool matchExact = false, bool useEndsWith = false)
+#endif
         {
-            Needle = needle;
-            MatchExact = matchExact;
-            UseEndsWith = useEndsWith;
+            this.Needle = needle;
+            this.MatchExact = matchExact;
+            this.UseEndsWith = useEndsWith;
         }
 
         #region Matching
@@ -43,23 +59,27 @@ namespace BinaryObjectScanner.Matching
         /// </summary>
         /// <param name="stack">List of strings to search for the given content</param>
         /// <returns>Tuple of success and matched item</returns>
+#if NET48
         public (bool, string) Match(IEnumerable<string> stack)
+#else
+        public (bool, string?) Match(IEnumerable<string>? stack)
+#endif
         {
             // If either array is null or empty, we can't do anything
-            if (stack == null || !stack.Any() || Needle == null || Needle.Length == 0)
+            if (stack == null || !stack.Any() || this.Needle == null || this.Needle.Length == 0)
                 return (false, null);
 
             // Preprocess the needle, if necessary
-            string procNeedle = MatchExact ? Needle : Needle.ToLowerInvariant();
+            string procNeedle = this.MatchExact ? this.Needle : this.Needle.ToLowerInvariant();
 
             foreach (string stackItem in stack)
             {
                 // Preprocess the stack item, if necessary
-                string procStackItem = MatchExact ? stackItem : stackItem.ToLowerInvariant();
+                string procStackItem = this.MatchExact ? stackItem : stackItem.ToLowerInvariant();
 
-                if (UseEndsWith && procStackItem.EndsWith(procNeedle))
+                if (this.UseEndsWith && procStackItem.EndsWith(procNeedle))
                     return (true, stackItem);
-                else if (!UseEndsWith && procStackItem.Contains(procNeedle))
+                else if (!this.UseEndsWith && procStackItem.Contains(procNeedle))
                     return (true, stackItem);
             }
 
diff --git a/BinaryObjectScanner.Matching/PathMatchSet.cs b/BinaryObjectScanner.Matching/PathMatchSet.cs
index cc84281f..a3e0a26a 100644
--- a/BinaryObjectScanner.Matching/PathMatchSet.cs
+++ b/BinaryObjectScanner.Matching/PathMatchSet.cs
@@ -18,7 +18,11 @@ namespace BinaryObjectScanner.Matching
         /// in which case it will be appended to the protection name, or `null`,
         /// in which case it will cause the protection to be omitted.
         /// </remarks>
-        public Func<string, IEnumerable<string>, string> GetVersion { get; set; }
+#if NET48
+        public Func<string, IEnumerable<string>, string> GetVersion { get; private set; }
+#else
+        public Func<string, IEnumerable<string>, string>? GetVersion { get; init; }
+#endif
 
         #region Constructors
 
@@ -28,11 +32,19 @@ namespace BinaryObjectScanner.Matching
         public PathMatchSet(List<string> needles, string protectionName)
             : this(needles, null, protectionName) { }
 
+#if NET48
         public PathMatchSet(string needle, Func<string, IEnumerable<string>, string> getVersion, string protectionName)
             : this(new List<string> { needle }, getVersion, protectionName) { }
 
         public PathMatchSet(List<string> needles, Func<string, IEnumerable<string>, string> getVersion, string protectionName)
             : this(needles.Select(n => new PathMatch(n)).ToList(), getVersion, protectionName) { }
+#else
+        public PathMatchSet(string needle, Func<string, IEnumerable<string>, string>? getVersion, string protectionName)
+            : this(new List<string> { needle }, getVersion, protectionName) { }
+
+        public PathMatchSet(List<string> needles, Func<string, IEnumerable<string>, string>? getVersion, string protectionName)
+            : this(needles.Select(n => new PathMatch(n)).ToList(), getVersion, protectionName) { }
+#endif
 
         public PathMatchSet(PathMatch needle, string protectionName)
             : this(new List<PathMatch>() { needle }, null, protectionName) { }
@@ -40,6 +52,7 @@ namespace BinaryObjectScanner.Matching
         public PathMatchSet(List<PathMatch> needles, string protectionName)
             : this(needles, null, protectionName) { }
 
+#if NET48
         public PathMatchSet(PathMatch needle, Func<string, IEnumerable<string>, string> getVersion, string protectionName)
             : this(new List<PathMatch>() { needle }, getVersion, protectionName) { }
 
@@ -49,6 +62,17 @@ namespace BinaryObjectScanner.Matching
             GetVersion = getVersion;
             ProtectionName = protectionName;
         }
+#else
+        public PathMatchSet(PathMatch needle, Func<string, IEnumerable<string>, string>? getVersion, string protectionName)
+            : this(new List<PathMatch>() { needle }, getVersion, protectionName) { }
+
+        public PathMatchSet(List<PathMatch> needles, Func<string, IEnumerable<string>, string>? getVersion, string protectionName)
+        {
+            Matchers = needles;
+            GetVersion = getVersion;
+            ProtectionName = protectionName;
+        }
+#endif
 
         #endregion
 
@@ -58,7 +82,7 @@ namespace BinaryObjectScanner.Matching
         /// Determine whether all path matches pass
         /// </summary>
         /// <param name="stack">List of strings to try to match</param>
-        /// <returns>Tuple of passing status and matching values</returns>        
+        /// <returns>Tuple of passing status and matching values</returns>
         public (bool, List<string>) MatchesAll(IEnumerable<string> stack)
         {
             // If no path matches are defined, we fail out
@@ -71,8 +95,12 @@ namespace BinaryObjectScanner.Matching
             // Loop through all path matches and make sure all pass
             foreach (var pathMatch in Matchers)
             {
+#if NET48
                 (bool match, string value) = pathMatch.Match(stack);
-                if (!match)
+#else
+                (bool match, string? value) = pathMatch.Match(stack);
+#endif
+                if (!match || value == null)
                     return (false, new List<string>());
                 else
                     values.Add(value);
@@ -85,8 +113,12 @@ namespace BinaryObjectScanner.Matching
         /// Determine whether any path matches pass
         /// </summary>
         /// <param name="stack">List of strings to try to match</param>
-        /// <returns>Tuple of passing status and first matching value</returns>        
+        /// <returns>Tuple of passing status and first matching value</returns>
+#if NET48
         public (bool, string) MatchesAny(IEnumerable<string> stack)
+#else
+        public (bool, string?) MatchesAny(IEnumerable<string> stack)
+#endif
         {
             // If no path matches are defined, we fail out
             if (Matchers == null || !Matchers.Any())
@@ -95,7 +127,11 @@ namespace BinaryObjectScanner.Matching
             // Loop through all path matches and make sure all pass
             foreach (var pathMatch in Matchers)
             {
+#if NET48
                 (bool match, string value) = pathMatch.Match(stack);
+#else
+                (bool match, string? value) = pathMatch.Match(stack);
+#endif
                 if (match)
                     return (true, value);
             }