Summary

Summary

Now that we know how the metadata is organized in principle, we are ready to examine the particular metadata items and the tables representing them. All further considerations shall concentrate on four metadata streams—#Strings, #Blob, #US, and #~—because the #GUID stream is referenced in one metadata table only (the Module table) and the #- stream (unoptimized metadata) is never emitted by the ILAsm compiler.

Here’s some advice for those of you who wonder if it would be a good idea to spoof the metadata header to get access to the data beyond the metadata under the pretense of manipulating the metadata: forget it. The runtime loader has safeguards analyzing the consistency of the metadata headers and the metadata itself. If an inconsistency is detected, the loader refuses to open the metadata streams. Tinkering with the metadata headers does not lead to erroneous or unpredictable behavior of the module; instead, it renders the module unloadable, period.

And on this cheerful note, let’s proceed to discussion of the “real” metadata items.