Merge pull request #1007 from TwanVanDongen/master

ArjReader throws exception for password protected archives.

src/SharpCompress/Readers/Arj/ArjReader.cs

@@ -60,6 +60,12 @@ namespace SharpCompress.Readers.Arj
                     "Multi volumes are currently not supported"
                 );
             }
+            if (mainHeader?.IsGabled == true)
+            {
+                throw new CryptographicException(
+                    "Password protected archives are currently not supported"
+                );
+            }
 
             if (_volume == null)
             {

tests/SharpCompress.Test/Arj/ArjReaderTests.cs

@@ -25,6 +25,12 @@ namespace SharpCompress.Test.Arj
         [Fact]
         public void Arj_Method4_Read() => Read("Arj.method4.arj");
 
+        [Fact]
+        public void Arj_Encrypted_Read()
+        {
+            var exception = Assert.Throws<CryptographicException>(() => Read("Arj.encrypted.arj"));
+        }
+
         [Fact]
         public void Arj_Multi_Reader()
         {