[PATCH 11/17] kexec_file: Move purgatories sha256 to common code

From: Philipp Rudo
Date: Mon Feb 12 2018 - 05:10:47 EST


The code to verify the new kernels sha digest are applicable for all
architectures. Move it to common code.

Signed-off-by: Philipp Rudo <prudo@xxxxxxxxxxxxxxxxxx>
---
arch/x86/purgatory/Makefile | 3 +++
arch/x86/purgatory/purgatory.c | 2 +-
{arch/x86/purgatory => include/linux}/sha256.h | 10 +++++++++-
{arch/x86/purgatory => lib}/sha256.c | 4 ++--
4 files changed, 15 insertions(+), 4 deletions(-)
rename {arch/x86/purgatory => include/linux}/sha256.h (63%)
rename {arch/x86/purgatory => lib}/sha256.c (99%)

diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
index 2f15a2ac4209..414eed6b5065 100644
--- a/arch/x86/purgatory/Makefile
+++ b/arch/x86/purgatory/Makefile
@@ -6,6 +6,9 @@ purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string
targets += $(purgatory-y)
PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))

+$(obj)/sha256.o: $(srctree)/lib/sha256.c
+ $(call if_changed_rule,cc_o_c)
+
LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
targets += purgatory.ro

diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c
index 470edad96bb9..025c34ac0d84 100644
--- a/arch/x86/purgatory/purgatory.c
+++ b/arch/x86/purgatory/purgatory.c
@@ -11,9 +11,9 @@
*/

#include <linux/bug.h>
+#include <linux/sha256.h>
#include <asm/purgatory.h>

-#include "sha256.h"
#include "../boot/string.h"

unsigned long purgatory_backup_dest __section(.kexec-purgatory);
diff --git a/arch/x86/purgatory/sha256.h b/include/linux/sha256.h
similarity index 63%
rename from arch/x86/purgatory/sha256.h
rename to include/linux/sha256.h
index 2867d9825a57..43a20ac33688 100644
--- a/arch/x86/purgatory/sha256.h
+++ b/include/linux/sha256.h
@@ -13,9 +13,17 @@
#include <linux/types.h>
#include <crypto/sha.h>

+/* Stand-alone implementation of the SHA256 algorithm. It is designed to
+ * have as little dependencies as possible so it can be used in the
+ * kexec_file purgatory. In other cases you should use the implementation in
+ * crypto/.
+ *
+ * For details see lib/sha256.c
+ */
+
extern int sha256_init(struct sha256_state *sctx);
extern int sha256_update(struct sha256_state *sctx, const u8 *input,
- unsigned int length);
+ unsigned int length);
extern int sha256_final(struct sha256_state *sctx, u8 *hash);

#endif /* SHA256_H */
diff --git a/arch/x86/purgatory/sha256.c b/lib/sha256.c
similarity index 99%
rename from arch/x86/purgatory/sha256.c
rename to lib/sha256.c
index 548ca675a14a..4400c832e2aa 100644
--- a/arch/x86/purgatory/sha256.c
+++ b/lib/sha256.c
@@ -16,9 +16,9 @@
*/

#include <linux/bitops.h>
+#include <linux/sha256.h>
+#include <linux/string.h>
#include <asm/byteorder.h>
-#include "sha256.h"
-#include "../boot/string.h"

static inline u32 Ch(u32 x, u32 y, u32 z)
{
--
2.13.5