Code signing: fix corrupted ZIP files

When copying a ZIP entry unmodified, we were storing the uncompressed
data as if it was compressed. This causes extraction of the .vsix to
fail.

Fix the corrupted ZIP file by storing compressed data instead of
uncompressed data.

Author: strager

dist/sign-release.go

@@ -374,11 +374,16 @@ func TransformZipGeneric(
 			return err
 		}
 		if transformResult.newFile == nil {
+			rawZIPEntryFile, err := zipEntry.OpenRaw()
+			if err != nil {
+				return err
+			}
+
 			destinationZipEntryFile, err := destinationZipFile.CreateRaw(&zipEntry.FileHeader)
 			if err != nil {
 				return err
 			}
-			_, err = io.Copy(destinationZipEntryFile, zipEntryFile)
+			_, err = io.Copy(destinationZipEntryFile, rawZIPEntryFile)
 			if err != nil {
 				return err
 			}