s390/ipl: read IPL report at early boot

Read the IPL Report block provided by secure-boot, add the entries
of the certificate list to the system key ring and print the list
of components.

PR: Adjust to Vasilys bootdata_preserved patch set. Preserve ipl_cert_list
for later use in kexec_file.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

security/integrity/platform_certs/load_ipl_s390.c

@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cred.h>
+#include <linux/err.h>
+#include <linux/efi.h>
+#include <linux/slab.h>
+#include <keys/asymmetric-type.h>
+#include <keys/system_keyring.h>
+#include <asm/boot_data.h>
+#include "../integrity.h"
+
+/*
+ * Load the certs contained in the IPL report created by the machine loader
+ * into the platform trusted keyring.
+ */
+static int __init load_ipl_certs(void)
+{
+	void *ptr, *end;
+	unsigned int len;
+
+	if (!ipl_cert_list_addr)
+		return 0;
+	/* Copy the certificates to the system keyring */
+	ptr = (void *) ipl_cert_list_addr;
+	end = ptr + ipl_cert_list_size;
+	while ((void *) ptr < end) {
+		len = *(unsigned int *) ptr;
+		ptr += sizeof(unsigned int);
+		add_to_platform_keyring("IPL:db", ptr, len);
+		ptr += len;
+	}
+	return 0;
+}
+late_initcall(load_ipl_certs);