crypto: sha256 - Make lib/crypto/sha256.c suitable for generic use

Before this commit lib/crypto/sha256.c has only been used in the s390 and
x86 purgatory code, make it suitable for generic use:

* Export interesting symbols
* Add  -D__DISABLE_EXPORTS to CFLAGS_sha256.o for purgatory builds to
  avoid the exports for the purgatory builds
* Add to lib/crypto/Makefile and crypto/Kconfig

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Hans de Goede 2019-08-17 16:24:33 +02:00 committed by Herbert Xu
parent 906a4bb97f
commit 01d3aee866
6 changed files with 17 additions and 2 deletions

View File

@ -10,6 +10,8 @@ PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
$(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE
$(call if_changed_rule,cc_o_c)
CFLAGS_sha256.o := -D__DISABLE_EXPORTS
$(obj)/mem.o: $(srctree)/arch/s390/lib/mem.S FORCE
$(call if_changed_rule,as_o_S)

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@ -9,6 +9,8 @@ PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
$(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE
$(call if_changed_rule,cc_o_c)
CFLAGS_sha256.o := -D__DISABLE_EXPORTS
LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
targets += purgatory.ro

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@ -849,6 +849,9 @@ config CRYPTO_SHA1_PPC_SPE
SHA-1 secure hash standard (DFIPS 180-4) implemented
using powerpc SPE SIMD instruction set.
config CRYPTO_LIB_SHA256
tristate
config CRYPTO_SHA256
tristate "SHA224 and SHA256 digest algorithm"
select CRYPTO_HASH

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@ -14,8 +14,9 @@
/*
* 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/.
* kexec_file purgatory. In other cases you should generally use the
* hash APIs from include/crypto/hash.h. Especially when hashing large
* amounts of data as those APIs may be hw-accelerated.
*
* For details see lib/crypto/sha256.c
*/

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@ -8,3 +8,6 @@ libarc4-y := arc4.o
obj-$(CONFIG_CRYPTO_LIB_DES) += libdes.o
libdes-y := des.o
obj-$(CONFIG_CRYPTO_LIB_SHA256) += libsha256.o
libsha256-y := sha256.o

View File

@ -12,6 +12,7 @@
*/
#include <linux/bitops.h>
#include <linux/export.h>
#include <linux/string.h>
#include <crypto/sha256.h>
#include <asm/unaligned.h>
@ -218,6 +219,7 @@ int sha256_init(struct sha256_state *sctx)
return 0;
}
EXPORT_SYMBOL(sha256_init);
int sha256_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
{
@ -248,6 +250,7 @@ int sha256_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
return 0;
}
EXPORT_SYMBOL(sha256_update);
int sha256_final(struct sha256_state *sctx, u8 *out)
{
@ -277,3 +280,4 @@ int sha256_final(struct sha256_state *sctx, u8 *out)
return 0;
}
EXPORT_SYMBOL(sha256_final);