Implement record pretty print. MDNS spec compliance improvements.

SmartHomeOS · Jul 19, 2024 · f5ce1e3 · f5ce1e3
1 parent cd60eb1
commit f5ce1e3
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Showing 14 changed files with 150 additions and 25 deletions.
diff --git a/TinyDNS/DNSResolver.cs b/TinyDNS/DNSResolver.cs
@@ -40,7 +40,19 @@ public DNSResolver(List<IPAddress> nameservers, ResolutionMode mode = Resolution
                 this.globalNameservers.Add(nameserver);
         }
 
-        public List<IPAddress> NameServers { get { return globalNameservers.ToList(); } }
+        public List<IPAddress> NameServers
+        { 
+            get
+            { 
+                return globalNameservers.ToList(); 
+            } 
+            set
+            {
+                globalNameservers.Clear();
+                foreach (IPAddress nameserver in value)
+                    globalNameservers.Add(nameserver);
+            }
+        }
 
         private void ReloadNameservers()
         {
@@ -70,7 +82,7 @@ public async Task<List<IPAddress>> ResolveHostV4(string hostname)
         {
             List<IPAddress> addresses = new List<IPAddress>();
             Message? response = await ResolveQuery(new QuestionRecord(hostname, DNSRecordType.A, false));
-            if (response == null || response.ResponseCode != DNSStatus.OK || (response.Answers.Length == 0 && response.Additionals.Length == 0))
+            if (response == null || response.ResponseCode != DNSStatus.NoError || (response.Answers.Length == 0 && response.Additionals.Length == 0))
                 return addresses;
 
             foreach (ResourceRecord answer in response.Answers)
@@ -90,7 +102,7 @@ public async Task<List<IPAddress>> ResolveHostV6(string hostname)
         {
             List<IPAddress> addresses = new List<IPAddress>();
             Message? response = await ResolveQuery(new QuestionRecord(hostname, DNSRecordType.AAAA, false));
-            if (response == null || response.ResponseCode != DNSStatus.OK || (response.Answers.Length == 0 && response.Additionals.Length == 0))
+            if (response == null || response.ResponseCode != DNSStatus.NoError || (response.Answers.Length == 0 && response.Additionals.Length == 0))
                 return addresses;
 
             foreach (ResourceRecord answer in response.Answers)
@@ -106,7 +118,7 @@ public async Task<List<IPAddress>> ResolveHostV6(string hostname)
             return addresses;
         }
 
-        public async Task<string?> ResolveIP(IPAddress address)
+        public async Task<Message?> ResolveIPRecord(IPAddress address)
         {
             byte[] addressBytes = address.GetAddressBytes();
             List<string> host;
@@ -132,8 +144,12 @@ public async Task<List<IPAddress>> ResolveHostV6(string hostname)
                 host.Add("IP6");
                 host.Add("ARPA");
             }
-            Message? response = await ResolveQuery(new QuestionRecord(host, DNSRecordType.PTR, false), privateQuery);
-            if (response == null || response.ResponseCode != DNSStatus.OK)
+            return await ResolveQuery(new QuestionRecord(host, DNSRecordType.PTR, false), privateQuery);
+        }
+        public async Task<string?> ResolveIP(IPAddress address)
+        {
+            Message? response = await ResolveIPRecord(address);
+            if (response == null || response.ResponseCode != DNSStatus.NoError)
                 return null;
 
             foreach (ResourceRecord answer in response.Answers)
@@ -225,7 +241,7 @@ public async Task<List<IPAddress>> ResolveHostV6(string hostname)
                             return response;
 
                         //For any other error try a different nameserver
-                        if (response.ResponseCode != DNSStatus.OK)
+                        if (response.ResponseCode != DNSStatus.NoError)
                             continue;
 
                         //Add new info to the cache

diff --git a/TinyDNS/Enums/DNSClass.cs b/TinyDNS/Enums/DNSClass.cs
@@ -14,12 +14,12 @@ namespace TinyDNS.Enums
 {
     public enum DNSClass : ushort
     {
-        Reserved = 0,
-        Internet = 1,
-        Unassigned = 2,
+        RESERVED = 0,
+        IN = 1,
+        UNASSIGNED = 2,
         CHAOS = 3,
-        Hesiod = 4,
-        None = 254,
-        Any = 255
+        HESIOD = 4,
+        NONE = 254,
+        ANY = 255
     }
 }
diff --git a/TinyDNS/Enums/DNSStatus.cs b/TinyDNS/Enums/DNSStatus.cs
@@ -17,7 +17,7 @@ public enum DNSStatus : byte
         /// <summary>
         /// No Error
         /// </summary>
-        OK = 0,
+        NoError = 0,
         /// <summary>
         /// Format Error
         /// </summary>

diff --git a/TinyDNS/MDNS.cs b/TinyDNS/MDNS.cs
@@ -93,14 +93,14 @@ private async Task ReceiveV4()
         {
             try
             {
-                Memory<byte> buffer = new byte[9000];
+                Memory<byte> buffer = new byte[8972];
                 while (!stop.IsCancellationRequested)
                 {
                     try
                     {
                         SocketReceiveFromResult received = await listenerV4!.ReceiveFromAsync(buffer, SocketFlags.None, new IPEndPoint(IPAddress.Any, PORT), stop.Token);
                         Message msg = new Message(buffer.Slice(0, received.ReceivedBytes).Span);
-                        if (msg.Response && msg.ResponseCode == DNSStatus.OK && (msg.Answers.Length > 0 || msg.Additionals.Length > 0))
+                        if (msg.Response && msg.ResponseCode == DNSStatus.NoError && (msg.Answers.Length > 0 || msg.Additionals.Length > 0))
                         {
                             if (messageCache.Cached(msg, ((IPEndPoint)received.RemoteEndPoint).Address))
                                 continue;
@@ -122,14 +122,14 @@ private async Task ReceiveV6()
         {
             try
             {
-                Memory<byte> buffer = new byte[9000];
+                Memory<byte> buffer = new byte[8952];
                 while (!stop.IsCancellationRequested)
                 {
                     try
                     {
                         SocketReceiveFromResult received = await listenerV6!.ReceiveFromAsync(buffer, SocketFlags.None, new IPEndPoint(IPAddress.IPv6Any, PORT), stop.Token);
                         Message msg = new Message(buffer.Slice(0, received.ReceivedBytes).Span);
-                        if (msg.Response && msg.ResponseCode == DNSStatus.OK && (msg.Answers.Length > 0 || msg.Additionals.Length > 0))
+                        if (msg.Response && msg.ResponseCode == DNSStatus.NoError && (msg.Answers.Length > 0 || msg.Additionals.Length > 0))
                         {
                             if (messageCache.Cached(msg, ((IPEndPoint)received.RemoteEndPoint).Address))
                                 continue;
@@ -189,9 +189,32 @@ public async Task QueryPointers(string domain)
             await SendMessage(msg);
         }
 
+        public async Task QueryIPv4Addresses(string domain)
+        {
+            Message msg = new Message();
+            msg.Response = false;
+            msg.Questions = [
+                new QuestionRecord(domain, DNSRecordType.A, false)
+            ];
+            await SendMessage(msg);
+        }
+
+        public async Task QueryIPv6Addresses(string domain)
+        {
+            Message msg = new Message();
+            msg.Response = false;
+            msg.Questions = [
+                new QuestionRecord(domain, DNSRecordType.AAAA, false)
+            ];
+            await SendMessage(msg);
+        }
+
         private async Task SendMessage(Message msg)
         {
             Memory<byte> buffer = new byte[512];
+            msg.TransactionID = 0;
+            msg.RecursionDesired = false;
+            msg.RecursionAvailable = false;
             int len = msg.ToBytes(buffer.Span);
             foreach (Socket sender in senders)
             {

diff --git a/TinyDNS/Message.cs b/TinyDNS/Message.cs
@@ -13,6 +13,7 @@
 using TinyDNS.Enums;
 using TinyDNS.Records;
 using System.Buffers.Binary;
+using System.Text;
 
 namespace TinyDNS
 {
@@ -143,5 +144,54 @@ public override bool Equals(object? obj)
         {
             return Equals(obj as Message);
         }
+
+        public override string ToString()
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.Append(";; Operation: ");
+            sb.Append(Operation);
+            sb.Append(", Status: ");
+            sb.Append(ResponseCode);
+            sb.Append(", ID: ");
+            sb.AppendLine(TransactionID.ToString());
+            sb.Append(";; Flags:");
+            if (Response)
+                sb.Append(" qr");
+            if (RecursionDesired)
+                sb.Append(" rd");
+            if (RecursionAvailable)
+                sb.Append(" ra");
+            sb.Append("; QUERY: ");
+            sb.Append(Questions.Length.ToString());
+            sb.Append(", ANSWER: ");
+            sb.Append(Answers.Length.ToString());
+            sb.Append(", AUTHORITY: ");
+            sb.Append(Authorities.Length.ToString());
+            sb.Append(", ADDITIONAL: ");
+            sb.AppendLine(Additionals.Length.ToString());
+            sb.AppendLine();
+            if (Questions.Length > 0)
+            {
+                sb.AppendLine(";; Questions:");
+                foreach (QuestionRecord question in Questions)
+                    sb.AppendLine(question.ToString());
+                sb.AppendLine();
+            }
+            if (Answers.Length > 0)
+            {
+                sb.AppendLine(";; Answers:");
+                foreach (ResourceRecord answer in Answers)
+                    sb.AppendLine(answer.ToString());
+                sb.AppendLine();
+            }
+            if (Authorities.Length > 0)
+            {
+                sb.AppendLine(";; Authority:");
+                foreach (ResourceRecord authority in Authorities)
+                    sb.AppendLine(authority.ToString());
+                sb.AppendLine();
+            }
+            return sb.ToString();
+        }
     }
 }
diff --git a/TinyDNS/Records/AAAARecord.cs b/TinyDNS/Records/AAAARecord.cs
@@ -49,5 +49,10 @@ public override int GetHashCode()
         {
             return Address.GetHashCode() + (int)Type;
         }
+
+        public override string ToString()
+        {
+            return base.ToString() + $"\t{Address}";
+        }
     }
 }
diff --git a/TinyDNS/Records/ARecord.cs b/TinyDNS/Records/ARecord.cs
@@ -49,5 +49,10 @@ public override int GetHashCode()
         {
             return Address.GetHashCode() + (int)Type;
         }
+
+        public override string ToString()
+        {
+            return base.ToString() + $"\t{Address}";
+        }
     }
 }
diff --git a/TinyDNS/Records/CNameRecord.cs b/TinyDNS/Records/CNameRecord.cs
@@ -41,5 +41,10 @@ public override bool Equals(ResourceRecord? other)
                 return base.Equals(other) && CNameLabels.SequenceEqual(otherCName.CNameLabels);
             return false;
         }
+
+        public override string ToString()
+        {
+            return base.ToString() + $"\t{CName}";
+        }
     }
 }
diff --git a/TinyDNS/Records/NSRecord.cs b/TinyDNS/Records/NSRecord.cs
@@ -41,5 +41,10 @@ public override bool Equals(ResourceRecord? other)
                 return base.Equals(other) && NSDomainLabels.SequenceEqual(otherNS.NSDomainLabels);
             return false;
         }
+
+        public override string ToString()
+        {
+            return base.ToString() + $"\t{NSDomain}";
+        }
     }
 }
diff --git a/TinyDNS/Records/PtrRecord.cs b/TinyDNS/Records/PtrRecord.cs
@@ -41,5 +41,10 @@ public override bool Equals(ResourceRecord? other)
                 return base.Equals(other) && DomainLabels.SequenceEqual(otherPtr.DomainLabels);
             return false;
         }
+
+        public override string ToString()
+        {
+            return base.ToString() + $"\t{Domain}";
+        }
     }
 }
diff --git a/TinyDNS/Records/QuestionRecord.cs b/TinyDNS/Records/QuestionRecord.cs
@@ -27,7 +27,7 @@ public QuestionRecord(List<string> domain, DNSRecordType recordType, bool unicas
         { 
             Name = domain;
             Type = recordType;
-            Class = DNSClass.Internet;
+            Class = DNSClass.IN;
             UnicastResponse = unicastResponse;
         }
 
@@ -65,5 +65,10 @@ public override bool Equals(object? obj)
         {
             return Equals(obj as QuestionRecord);
         }
+
+        public override string ToString()
+        {
+            return $"{string.Join('.',Name)}\t{Class}\t{Type}";
+        }
     }
 }
diff --git a/TinyDNS/Records/ResourceRecord.cs b/TinyDNS/Records/ResourceRecord.cs
@@ -109,5 +109,11 @@ internal static ResourceRecord Parse(string line)
             }
             return record;
         }
+
+        public override string ToString()
+        {
+            int ttl = (int)Math.Ceiling((Expires - DateTime.Now).TotalSeconds);
+            return $"{Name}\t{ttl}\t{Class}\t{Type}";
+        }
     }
 }
diff --git a/TinyDNS/Records/ResourceRecordHeader.cs b/TinyDNS/Records/ResourceRecordHeader.cs
@@ -41,7 +41,7 @@ public ResourceRecordHeader(string[] columns)
             Labels = DomainParser.Parse(columns[0]);
             Type = DNSRecordParser.Parse(columns[2]);
             uint ttl = uint.Parse(columns[1]);
-            Class = DNSClass.Internet;
+            Class = DNSClass.IN;
             Expires = DateTime.Now + TimeSpan.FromSeconds(ttl);
         }
 

diff --git a/TinyDNS/TinyDNS.csproj b/TinyDNS/TinyDNS.csproj
@@ -4,11 +4,11 @@
     <TargetFrameworks>net80</TargetFrameworks>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
-	<Version>0.5</Version>
-	<PackageLicenseExpression>AGPL-3.0-or-later</PackageLicenseExpression>
-	<PackageReadmeFile>README.md</PackageReadmeFile>
-	<Authors>jdomnitz</Authors>
-	<Company>SmartHomeOS and Contributors</Company>
+    <Version>0.5</Version>
+    <PackageLicenseExpression>AGPL-3.0-or-later</PackageLicenseExpression>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+    <Authors>jdomnitz</Authors>
+    <Company>SmartHomeOS and Contributors</Company>
   </PropertyGroup>
 
   <ItemGroup>