Better exceptions for FromBytes

NZSmartie · Nov 29, 2017 · 0ac5f88 · 0ac5f88
1 parent 4436a9f
commit 0ac5f88
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Showing 3 changed files with 17 additions and 8 deletions.
diff --git a/src/CoAPNet/CoapMessage.cs b/src/CoAPNet/CoapMessage.cs
@@ -308,7 +308,7 @@ public void FromBytes(byte[] data)
                 _token = data.Skip(4).Take(data[0] & 0x0F).ToArray();
 
             // Catch all the CoapOptionExceptions and throw them after all the options have been parsed.
-            var badOptions = new List<int>();
+            var badOptions = new List<CoapOptionException>();
             var optionDelta = 0;
             for(var i = offset; i<data.Length; i++)
             {
@@ -345,9 +345,9 @@ public void FromBytes(byte[] data)
                     if (option != null)
                         Options.Add(option);
                 }
-                catch (CoapOptionException)
+                catch (CoapOptionException ex)
                 {
-                    badOptions.Add(optCode + optionDelta);
+                    badOptions.Add(ex);
                 }
 
                 i += dataLen;
@@ -358,8 +358,11 @@ public void FromBytes(byte[] data)
             if (new int[] {1, 6, 7}.Contains(code / 100))
                 throw new CoapMessageFormatException("Message.Code can not use reserved classes");
 
-            if (badOptions.Count > 0)
-                throw new CoapOptionException($"Unsupported critical option ({string.Join(", ", badOptions)})");
+            if (badOptions.Count == 1)
+                throw badOptions.First();
+
+            if (badOptions.Count > 1)
+                throw new AggregateException(badOptions);
         }
 
         /// <summary>

diff --git a/src/CoAPNet/CoapOptions.cs b/src/CoAPNet/CoapOptions.cs
@@ -292,6 +292,9 @@ public byte[] GetBytes()
             if (_type == OptionType.Empty)
                 return new byte[0];
 
+            if (_length < _minLength || _length > _maxLength)
+                throw new CoapOptionException($"Invalid option length ({_length}). Must be between {_minLength} and {_maxLength} bytes");
+
             if (_type == OptionType.Opaque)
                 return (byte[])_value;
 
@@ -320,6 +323,9 @@ public void FromBytes(byte[] data)
                 return;
             }
 
+            if(data.Length < _minLength || data.Length > _maxLength)
+                throw new CoapOptionException($"Invalid option length ({data.Length}). Must be between {_minLength} and {_maxLength} bytes");
+
             if (_type == OptionType.Opaque)
             {
                 ValueOpaque = data;

diff --git a/tests/CoAPNet.Tests/CoapOptionsTests.cs b/tests/CoAPNet.Tests/CoapOptionsTests.cs
@@ -391,7 +391,7 @@ public void TestOptionSize1()
         [Test]
         public void TestOpaqueOption()
         {
-            var option = new CoapOption(0, type: OptionType.Opaque);
+            var option = new CoapOption(0, type: OptionType.Opaque, maxLength: 256);
 
             option.ValueOpaque = new byte[] {0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0};
             Assert.AreEqual(8, option.Length);
@@ -410,13 +410,13 @@ public void TestOpaqueOption()
         [TestCase(0x12345678u, 4, new byte[] {0x12, 0x34, 0x56, 0x78})]
         public void TestValueOption(uint value, int length, byte[] expected)
         {
-            var optionToBytes = new CoapOption(0, type: OptionType.UInt);
+            var optionToBytes = new CoapOption(0, type: OptionType.UInt, maxLength: 4);
 
             optionToBytes.ValueUInt = value;
             Assert.AreEqual(length, optionToBytes.Length);
             Assert.AreEqual(expected, optionToBytes.GetBytes());
 
-            var optionFromBytes = new CoapOption(0, type: OptionType.UInt);
+            var optionFromBytes = new CoapOption(0, type: OptionType.UInt, maxLength: 4);
 
             optionFromBytes.FromBytes(expected);
             Assert.AreEqual(length, optionFromBytes.Length);