File 2007-boot-pe-introduce-.binrel-as-PE-metadata.patch of Package systemd

From 879d1efa58e31dabe8b9ecd538ecd6b0ac632e30 Mon Sep 17 00:00:00 2001
From: Raito Bezarius <masterancpp@gmail.com>
Date: Sat, 22 Jul 2023 18:03:11 +0200
Subject: [PATCH 7/7] boot(pe): introduce `.binrel` as PE metadata

Following
https://github.com/systemd/systemd/pull/28057/files#r1233760527,

we realized the need for EFI metadata, as EFI device paths will not
always carry the filename information.

Here is an attempt to materialize it as a PE section `.sdmeta` to avoid
piling up many sections which will be all aligned to full pages in
memory and 512 bytes on disk.

This is a structured data section for any PE metadata, it starts with a
`filename` field.

In a future PR, stubs, addons and systemd-boot will make use of that
section.
---
 src/boot/efi/addon-util.h | 2 ++
 src/boot/efi/addon.c      | 4 ++++
 src/boot/efi/pe.h         | 6 ++++++
 src/boot/efi/stub.c       | 6 +++++-
 src/boot/efi/stub.h       | 4 ++++
 5 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 src/boot/efi/stub.h

diff --git a/src/boot/efi/addon-util.h b/src/boot/efi/addon-util.h
index f1883fdcdb..a52312e596 100644
--- a/src/boot/efi/addon-util.h
+++ b/src/boot/efi/addon-util.h
@@ -8,5 +8,7 @@
 #define SYSTEMD_ADDON_MEDIA_GUID \
         GUID_DEF(0x97ac68bf, 0xc741, 0x4bbb, 0xb7, 0xbf, 0x7f, 0x6c, 0xcc, 0x00, 0x8a, 0x7e)
 
+#define ADDON_FILENAME "sd-addon"
+
 EFI_STATUS addons_install_proto(EFI_LOADED_IMAGE_PROTOCOL *loaded_image, char16_t * const *addons);
 EFI_STATUS addons_unload_proto(EFI_HANDLE *addons);
diff --git a/src/boot/efi/addon.c b/src/boot/efi/addon.c
index 95b29daf55..691862aff5 100644
--- a/src/boot/efi/addon.c
+++ b/src/boot/efi/addon.c
@@ -5,6 +5,10 @@
 
 /* Magic string for recognizing our own binaries */
 DECLARE_NOALLOC_SECTION(".sdmagic", "#### LoaderInfo: systemd-addon " GIT_VERSION " ####");
+_used_ _section_(".binrel") static const struct pe_metadata metadata = {
+        .fname = ADDON_FILENAME
+};
+
 
 /* This is intended to carry data, not to be executed */
 
diff --git a/src/boot/efi/pe.h b/src/boot/efi/pe.h
index 7e2258fceb..261aa9eb7e 100644
--- a/src/boot/efi/pe.h
+++ b/src/boot/efi/pe.h
@@ -3,6 +3,12 @@
 
 #include "efi.h"
 
+/* This is used to hold PE-specific metadata
+ * under the section `.sdmeta`               */
+struct pe_metadata {
+        const char *fname;
+};
+
 EFI_STATUS pe_memory_locate_sections(
                 const void *base,
                 const char * const sections[],
diff --git a/src/boot/efi/stub.c b/src/boot/efi/stub.c
index 94a34e953c..53c04668a8 100644
--- a/src/boot/efi/stub.c
+++ b/src/boot/efi/stub.c
@@ -1,5 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include "addon-util.h"
+#include "stub.h"
 #include "cpio.h"
 #include "device-path-util.h"
 #include "devicetree.h"
@@ -23,8 +25,10 @@
 
 /* magic string to find in the binary image */
 DECLARE_NOALLOC_SECTION(".sdmagic", "#### LoaderInfo: systemd-stub " GIT_VERSION " ####");
-
 DECLARE_SBAT(SBAT_STUB_SECTION_TEXT);
+_used_ _section_(".binrel") static const struct pe_metadata metadata = {
+        .fname = STUB_FILENAME
+};
 
 struct addon_entry {
         char16_t *source_path;
diff --git a/src/boot/efi/stub.h b/src/boot/efi/stub.h
new file mode 100644
index 0000000000..aae6b03ec4
--- /dev/null
+++ b/src/boot/efi/stub.h
@@ -0,0 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#define STUB_FILENAME "sd-stub"
-- 
2.35.3