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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/kernel/ima_arch.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/kernel/ima_arch.c')
-rw-r--r--arch/powerpc/kernel/ima_arch.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/ima_arch.c b/arch/powerpc/kernel/ima_arch.c
new file mode 100644
index 0000000000..b7029beed8
--- /dev/null
+++ b/arch/powerpc/kernel/ima_arch.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 IBM Corporation
+ * Author: Nayna Jain
+ */
+
+#include <linux/ima.h>
+#include <asm/secure_boot.h>
+
+bool arch_ima_get_secureboot(void)
+{
+ return is_ppc_secureboot_enabled();
+}
+
+/*
+ * The "secure_rules" are enabled only on "secureboot" enabled systems.
+ * These rules verify the file signatures against known good values.
+ * The "appraise_type=imasig|modsig" option allows the known good signature
+ * to be stored as an xattr or as an appended signature.
+ *
+ * To avoid duplicate signature verification as much as possible, the IMA
+ * policy rule for module appraisal is added only if CONFIG_MODULE_SIG
+ * is not enabled.
+ */
+static const char *const secure_rules[] = {
+ "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig",
+#ifndef CONFIG_MODULE_SIG
+ "appraise func=MODULE_CHECK appraise_type=imasig|modsig",
+#endif
+ NULL
+};
+
+/*
+ * The "trusted_rules" are enabled only on "trustedboot" enabled systems.
+ * These rules add the kexec kernel image and kernel modules file hashes to
+ * the IMA measurement list.
+ */
+static const char *const trusted_rules[] = {
+ "measure func=KEXEC_KERNEL_CHECK",
+ "measure func=MODULE_CHECK",
+ NULL
+};
+
+/*
+ * The "secure_and_trusted_rules" contains rules for both the secure boot and
+ * trusted boot. The "template=ima-modsig" option includes the appended
+ * signature, when available, in the IMA measurement list.
+ */
+static const char *const secure_and_trusted_rules[] = {
+ "measure func=KEXEC_KERNEL_CHECK template=ima-modsig",
+ "measure func=MODULE_CHECK template=ima-modsig",
+ "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig",
+#ifndef CONFIG_MODULE_SIG
+ "appraise func=MODULE_CHECK appraise_type=imasig|modsig",
+#endif
+ NULL
+};
+
+/*
+ * Returns the relevant IMA arch-specific policies based on the system secure
+ * boot state.
+ */
+const char *const *arch_get_ima_policy(void)
+{
+ if (is_ppc_secureboot_enabled()) {
+ if (IS_ENABLED(CONFIG_MODULE_SIG))
+ set_module_sig_enforced();
+
+ if (is_ppc_trustedboot_enabled())
+ return secure_and_trusted_rules;
+ else
+ return secure_rules;
+ } else if (is_ppc_trustedboot_enabled()) {
+ return trusted_rules;
+ }
+
+ return NULL;
+}