handle value escaping

Author: thboop

src/Runner.Worker/Container/DockerUtil.cs

@@ -68,7 +68,7 @@ public static string CreateEscapedOption(string flag, string key)
             {
                 return "";
             }
-            return $"{flag} \"{EscapeString(key)}\"";
+            return $"{flag} {EscapeString(key)}";
         }
 
         public static string CreateEscapedOption(string flag, string key, string value)
@@ -77,12 +77,28 @@ public static string CreateEscapedOption(string flag, string key, string value)
             {
                 return "";
             }
-            return $"{flag} \"{EscapeString(key)}={value.Replace("\"", "\\\"")}\"";
+            var escapedString = EscapeString($"{key}={value}");
+            return $"{flag} {escapedString}";
         }
 
         private static string EscapeString(string value)
         {
-            return value.Replace("\\", "\\\\").Replace("\"", "\\\"");
+            if (String.IsNullOrEmpty(value))
+            {
+                return "";
+            }
+            // Dotnet escaping rules are weird here, we can only escape \ if it precedes a "
+            // If a double quotation mark follows two or an even number of backslashes, each proceeding backslash pair is replaced with one backslash and the double quotation mark is removed.
+            // If a double quotation mark follows an odd number of backslashes, including just one, each preceding pair is replaced with one backslash and the remaining backslash is removed; however, in this case the double quotation mark is not removed.
+            // https://docs.microsoft.com/en-us/dotnet/api/system.environment.getcommandlineargs?redirectedfrom=MSDN&view=net-6.0#remarks
+
+            // First, find any \ followed by a " and double the number of \ + 1.
+             value = Regex.Replace(value, @"(\\*)" + "\"", @"$1$1\" + "\"");
+            // Next, what if it ends in `\`, it would escape the end quote. So, we need to detect that at the end of the string and perform the same escape
+            // Luckily, we can just use the $ character with detects the end of string in regex
+            value = Regex.Replace(value, @"(\\+)$", @"$1$1");
+            // Finally, wrap it in quotes
+            return $"\"{value}\"";
         }
     }
 }

src/Test/L0/Container/DockerUtilL0.cs

@@ -149,13 +149,12 @@ public void ParseRegistryHostnameFromImageName(string input, string expected)
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]
         [InlineData("", "")]
-        [InlineData("HOME alpine:3.8 sh -c id #", "HOME alpine:3.8 sh -c id #")]
-        [InlineData("HOME \"alpine:3.8 sh -c id #", "HOME \\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \\\"alpine:3.8 sh -c id #", "HOME \\\\\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \\\\\"alpine:3.8 sh -c id #", "HOME \\\\\\\\\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \"\"alpine:3.8 sh -c id #", "HOME \\\"\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \\\"\"alpine:3.8 sh -c id #", "HOME \\\\\\\"\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \"\\\"alpine:3.8 sh -c id #", "HOME \\\"\\\\\\\"alpine:3.8 sh -c id #")]
+        [InlineData("foo", "foo")]
+        [InlineData("foo \\ bar", "foo \\ bar")]
+        [InlineData("foo \\", "foo \\\\")]
+        [InlineData("foo \\\\", "foo \\\\\\\\")]
+        [InlineData("foo \\\" bar", "foo \\\\\" bar")]
+        [InlineData("foo \\\\\" bar", "foo \\\\\\\\\" bar")]
         public void CreateEscapedOption_keyOnly(string input, string escaped)
         {
             var flag = "--example";
@@ -175,15 +174,11 @@ public void CreateEscapedOption_keyOnly(string input, string escaped)
         [Theory]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]
-        [InlineData("HOME", "", "HOME", "")]
-        [InlineData("HOME alpine:3.8 sh -c id #", "HOME alpine:3.8 sh -c id #", "HOME alpine:3.8 sh -c id #", "HOME alpine:3.8 sh -c id #")]
-        [InlineData("HOME \"alpine:3.8 sh -c id #", "HOME \"alpine:3.8 sh -c id #", "HOME \\\"alpine:3.8 sh -c id #", "HOME \\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \\\"alpine:3.8 sh -c id #", "HOME \\\"alpine:3.8 sh -c id #", "HOME \\\\\\\"alpine:3.8 sh -c id #", "HOME \\\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \\\\\"alpine:3.8 sh -c id #", "HOME \\\\\"alpine:3.8 sh -c id #", "HOME \\\\\\\\\\\"alpine:3.8 sh -c id #", "HOME \\\\\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \"\"alpine:3.8 sh -c id #", "HOME \"\"alpine:3.8 sh -c id #", "HOME \\\"\\\"alpine:3.8 sh -c id #", "HOME \\\"\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \\\"\"alpine:3.8 sh -c id #", "HOME \\\"\"alpine:3.8 sh -c id #", "HOME \\\\\\\"\\\"alpine:3.8 sh -c id #", "HOME \\\\\"\\\"alpine:3.8 sh -c id #")]
-        [InlineData("HOME \"\\\"alpine:3.8 sh -c id #", "HOME \"\\\"alpine:3.8 sh -c id #", "HOME \\\"\\\\\\\"alpine:3.8 sh -c id #", "HOME \\\"\\\\\"alpine:3.8 sh -c id #")]
-        public void CreateEscapedOption_keyValue(string keyInput, string valueInput, string escapedKey, string escapedValue)
+        [InlineData("foo", "bar", "foo=bar")]
+        [InlineData("foo\\", "bar", "foo\\=bar")]
+        [InlineData("foo\\", "bar\\", "foo\\=bar\\\\")]
+        [InlineData("foo \\","bar \\", "foo \\\\=bar \\\\")]
+        public void CreateEscapedOption_keyValue(string keyInput, string valueInput, string escapedString)
         {
             var flag = "--example";
             var actual = DockerUtil.CreateEscapedOption(flag, keyInput, valueInput);
@@ -194,7 +189,7 @@ public void CreateEscapedOption_keyValue(string keyInput, string valueInput, str
             }
             else
             {
-                expected = $"{flag} \"{escapedKey}={escapedValue}\"";
+                expected = $"{flag} \"{escapedString}\"";
             }
             Assert.Equal(expected, actual);
         }