[PATCH 2/3] libebl: recognize FDO Packaging Metadata ELF note

[Mark Wielaard <mark@klomp.org>]

From: Luca Boccassi <bluca@debian.org>

As defined on: https://systemd.io/COREDUMP_PACKAGE_METADATA/
this note will be used starting from Fedora 36. Allow
readelf --notes to pretty print it:

Note section [ 3] '.note.package' of 76 bytes at offset 0x2e8:
  Owner          Data size  Type
  FDO                   57  FDO_PACKAGING_METADATA
    Packaging Metadata: {"type":"deb","name":"fsverity-utils","version":"1.3-1"}

Signed-off-by: Luca Boccassi <luca.boccassi@microsoft.com>
---
 libebl/ChangeLog            | 5 +++++
 libebl/eblobjnote.c         | 4 ++++
 libebl/eblobjnotetypename.c | 3 +++
 3 files changed, 12 insertions(+)

diff --git a/libebl/ChangeLog b/libebl/ChangeLog
index da690a40..2e31e75d 100644
--- a/libebl/ChangeLog
+++ b/libebl/ChangeLog
@@ -1,3 +1,8 @@
+2021-12-21  Luca Boccassi  <bluca@debian.org>
+
+	* eblobjnote.c (ebl_object_note): Handle NT_FDO_PACKAGING_METADATA.
+	* eblobjnotetypename.c (ebl_object_note_type_name): Likewise.
+
 2021-09-06  Dmitry V. Levin  <ldv@altlinux.org>
 
 	* eblopenbackend.c (openbackend): Remove cast of calloc return value.
diff --git a/libebl/eblobjnote.c b/libebl/eblobjnote.c
index 36efe275..5a7c5c62 100644
--- a/libebl/eblobjnote.c
+++ b/libebl/eblobjnote.c
@@ -288,6 +288,10 @@ ebl_object_note (Ebl *ebl, uint32_t namesz, const char *name, uint32_t type,
       if (descsz == 0 && type == NT_VERSION)
 	return;
 
+      if (strcmp ("FDO", name) == 0 && type == NT_FDO_PACKAGING_METADATA
+	  && descsz > 0 && desc[descsz - 1] == '\0')
+	printf("    Packaging Metadata: %.*s\n", (int) descsz, desc);
+
       /* Everything else should have the "GNU" owner name.  */
       if (strcmp ("GNU", name) != 0)
 	return;
diff --git a/libebl/eblobjnotetypename.c b/libebl/eblobjnotetypename.c
index 4662906d..473a1f2f 100644
--- a/libebl/eblobjnotetypename.c
+++ b/libebl/eblobjnotetypename.c
@@ -101,6 +101,9 @@ ebl_object_note_type_name (Ebl *ebl, const char *name, uint32_t type,
 	  return buf;
 	}
 
+      if (strcmp (name, "FDO") == 0 && type == NT_FDO_PACKAGING_METADATA)
+	return "FDO_PACKAGING_METADATA";
+
       if (strcmp (name, "GNU") != 0)
 	{
 	  /* NT_VERSION is special, all data is in the name.  */
-- 
2.30.2