util: add module to parse PE32+ files

Add an new module with utility functions to inspect PE32+ files,
mainly listing the sections and their addresses and sizes.
Include a simple test to check that we can successfully parse the
EFI stub contained in systemd (systemd-udev package).

test/mod/test_util_pe32p.py

@@ -0,0 +1,55 @@
+#
+# Test for the util.lvm2 module
+#
+
+import io
+import os
+
+import pytest
+
+from osbuild.util import pe32p
+
+EFI_STUB = "/usr/lib/systemd/boot/efi/linuxx64.efi.stub"
+
+
+def have_efi_stub() -> bool:
+    return os.path.exists(EFI_STUB)
+
+
+@pytest.mark.skipif(not have_efi_stub(), reason="require systemd efi stub")
+def test_basic():
+    with open(EFI_STUB, "rb") as f:
+        coff = pe32p.read_coff_header(f)
+        assert coff
+        opt = pe32p.read_optional_header(f, coff)
+        assert opt
+        sections = pe32p.read_sections(f, coff)
+
+    assert sections, "No sections found in stub"
+
+
+@pytest.mark.skipif(not have_efi_stub(), reason="require systemd efi stub")
+def test_basic_no_coff():
+    # check the API versions that re-reads the CoffHeader
+    with open(EFI_STUB, "rb") as f:
+        coff = pe32p.read_coff_header(f)
+        assert coff
+        f.seek(0, io.SEEK_SET)
+        opt = pe32p.read_optional_header(f)
+        f.seek(0, io.SEEK_SET)
+        assert opt
+        f.seek(0, io.SEEK_SET)
+        sections = pe32p.read_sections(f)
+
+    assert sections, "No sections found in stub"
+
+    with open(EFI_STUB, "rb") as f:
+        coff_check = pe32p.read_coff_header(f)
+        assert coff_check
+        assert coff == coff_check
+        opt_check = pe32p.read_optional_header(f, coff)
+        assert opt_check
+        assert opt == opt_check
+        sections_check = pe32p.read_sections(f, coff)
+        assert sections_check
+        assert sections == sections_check