Merge pull request #26 from jlagnese-allata/master

Another fix required for correct signature using query string arrays
tsibelman · May 12, 2020 · 8f05baf · 8f05baf
2 parents 701e47f + 35d9864
commit 8f05baf
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/Aws4Signer/AWS4RequestSigner.cs b/Aws4Signer/AWS4RequestSigner.cs
@@ -162,9 +162,12 @@ private static string GetCanonicalQueryParams(HttpRequestMessage request)
                 }
                 else
                 {
-                    // Query params must be escaped in upper case (i.e. "%2C", not "%2c").
                     // Handles multiple values per query parameter
-                    var queryValues = querystring[key].Split(',').Select(v => $"{Uri.EscapeDataString(key)}={Uri.EscapeDataString(v)}");
+                    var queryValues = querystring[key].Split(',')
+                        // Order by value alphanumerically (required for correct canonical string)
+                        .OrderBy(v => v)
+                        // Query params must be escaped in upper case (i.e. "%2C", not "%2c").
+                        .Select(v => $"{Uri.EscapeDataString(key)}={Uri.EscapeDataString(v)}");
 
                     values.Add(Uri.EscapeDataString(key), queryValues);
                 }