In preparation for using blake2s in the RNG, we change the way that it
is wired-in to the build system. Instead of kconfig mazes and ifdefs, we
use weak symbols, so that an arch version can override the generic
version. Then we include the generic version in lib-y, so that it can be
removed from the image if the arch version doesn't fallback to it (as is
the case on arm though not x86). The result should be a bit simpler and
smaller than the code it replaces.
Discussed-with: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
---
Hi Masahiro,
This is a commit I'm working on as part of a change to the RNG, which
got broken out into something standalone because it wound up being a bit
more involved than originally conceived. With Ard's help, this is using
weak symbols with the generic code in lib-y, but the only way we figured
to actually include the lib.a file was via this unseemly
KBUILD_VMLINUX_LIBS line below, which doesn't seem very okay. I tried
adding `libs-y += lib/crypto/` to lib/Makefile, but it seemed like the
build system ignored it. I figure there's probably a right way to do
this, so thought I should send you this RFC to look at first.
Alternatively, if the KBUILD_VMLINUX_LIBS trick is somehow okay, that'd
be useful to know too.
Thanks,
Jason
Makefile | 1 +
arch/arm/crypto/Kconfig | 3 +--
arch/arm/crypto/blake2s-core.S | 8 ++++----
arch/arm/crypto/blake2s-glue.c | 6 +++---
arch/s390/configs/debug_defconfig | 1 -
arch/s390/configs/defconfig | 1 -
arch/x86/crypto/blake2s-glue.c | 11 +++++------
crypto/Kconfig | 5 +----
drivers/net/Kconfig | 1 -
include/crypto/internal/blake2s.h | 6 +++---
lib/crypto/Kconfig | 25 -------------------------
lib/crypto/Makefile | 7 +++----
lib/crypto/blake2s-generic.c | 6 +++++-
lib/crypto/blake2s.c | 6 ------
14 files changed, 26 insertions(+), 61 deletions(-)
diff --git a/Makefile b/Makefile
index d85f1ff79f5c..4b4a2bec020c 100644
--- a/Makefile
+++ b/Makefile
@@ -1120,6 +1120,7 @@ else
KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
endif
KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
+KBUILD_VMLINUX_LIBS += lib/crypto/lib.a
export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
index 2b575792363e..47cb22645746 100644
--- a/arch/arm/crypto/Kconfig
+++ b/arch/arm/crypto/Kconfig
@@ -63,8 +63,7 @@ config CRYPTO_SHA512_ARM
using optimized ARM assembler and NEON, when available.
config CRYPTO_BLAKE2S_ARM
- tristate "BLAKE2s digest algorithm (ARM)"
- select CRYPTO_ARCH_HAVE_LIB_BLAKE2S
+ bool "BLAKE2s digest algorithm (ARM)"
help
BLAKE2s digest algorithm optimized with ARM scalar instructions. This
is faster than the generic implementations of BLAKE2s and BLAKE2b, but
diff --git a/arch/arm/crypto/blake2s-core.S b/arch/arm/crypto/blake2s-core.S
index 86345751bbf3..df40e46601f1 100644
--- a/arch/arm/crypto/blake2s-core.S
+++ b/arch/arm/crypto/blake2s-core.S
@@ -167,8 +167,8 @@
.endm
//
-// void blake2s_compress_arch(struct blake2s_state *state,
-// const u8 *block, size_t nblocks, u32 inc);
+// void blake2s_compress(struct blake2s_state *state,
+// const u8 *block, size_t nblocks, u32 inc);
//
// Only the first three fields of struct blake2s_state are used:
// u32 h[8]; (inout)
@@ -176,7 +176,7 @@
// u32 f[2]; (in)
//
.align 5
-ENTRY(blake2s_compress_arch)
+ENTRY(blake2s_compress)
push {r0-r2,r4-r11,lr} // keep this an even number
.Lnext_block:
@@ -303,4 +303,4 @@ ENTRY(blake2s_compress_arch)
str r3, [r12], #4
bne 1b
b .Lcopy_block_done
-ENDPROC(blake2s_compress_arch)
+ENDPROC(blake2s_compress)
diff --git a/arch/arm/crypto/blake2s-glue.c b/arch/arm/crypto/blake2s-glue.c
index f2cc1e5fc9ec..09d3a0cabd2c 100644
--- a/arch/arm/crypto/blake2s-glue.c
+++ b/arch/arm/crypto/blake2s-glue.c
@@ -11,17 +11,17 @@
#include <linux/module.h>
/* defined in blake2s-core.S */
-EXPORT_SYMBOL(blake2s_compress_arch);
+EXPORT_SYMBOL(blake2s_compress);
static int crypto_blake2s_update_arm(struct shash_desc *desc,
const u8 *in, unsigned int inlen)
{
- return crypto_blake2s_update(desc, in, inlen, blake2s_compress_arch);
+ return crypto_blake2s_update(desc, in, inlen, blake2s_compress);
}
static int crypto_blake2s_final_arm(struct shash_desc *desc, u8 *out)
{
- return crypto_blake2s_final(desc, out, blake2s_compress_arch);
+ return crypto_blake2s_final(desc, out, blake2s_compress);
}
#define BLAKE2S_ALG(name, driver_name, digest_size) \
diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index e45cc27716de..caa3d1d6a0e8 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -757,7 +757,6 @@ CONFIG_CRYPTO_USER_API_SKCIPHER=m
CONFIG_CRYPTO_USER_API_RNG=m
CONFIG_CRYPTO_USER_API_AEAD=m
CONFIG_CRYPTO_STATS=y
-CONFIG_CRYPTO_LIB_BLAKE2S=m
CONFIG_CRYPTO_LIB_CURVE25519=m
CONFIG_CRYPTO_LIB_CHACHA20POLY1305=m
CONFIG_ZCRYPT=m
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 1c750bfca2d8..fffc6af5358c 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -744,7 +744,6 @@ CONFIG_CRYPTO_USER_API_SKCIPHER=m
CONFIG_CRYPTO_USER_API_RNG=m
CONFIG_CRYPTO_USER_API_AEAD=m
CONFIG_CRYPTO_STATS=y
-CONFIG_CRYPTO_LIB_BLAKE2S=m
CONFIG_CRYPTO_LIB_CURVE25519=m
CONFIG_CRYPTO_LIB_CHACHA20POLY1305=m
CONFIG_ZCRYPT=m
diff --git a/arch/x86/crypto/blake2s-glue.c b/arch/x86/crypto/blake2s-glue.c
index a40365ab301e..ef91a3167d27 100644
--- a/arch/x86/crypto/blake2s-glue.c
+++ b/arch/x86/crypto/blake2s-glue.c
@@ -28,9 +28,8 @@ asmlinkage void blake2s_compress_avx512(struct blake2s_state *state,
static __ro_after_init DEFINE_STATIC_KEY_FALSE(blake2s_use_ssse3);
static __ro_after_init DEFINE_STATIC_KEY_FALSE(blake2s_use_avx512);
-void blake2s_compress_arch(struct blake2s_state *state,
- const u8 *block, size_t nblocks,
- const u32 inc)
+void blake2s_compress(struct blake2s_state *state, const u8 *block,
+ size_t nblocks, const u32 inc)
{
/* SIMD disables preemption, so relax after processing each page. */
BUILD_BUG_ON(SZ_4K / BLAKE2S_BLOCK_SIZE < 8);
@@ -56,17 +55,17 @@ void blake2s_compress_arch(struct blake2s_state *state,
block += blocks * BLAKE2S_BLOCK_SIZE;
} while (nblocks);
}
-EXPORT_SYMBOL(blake2s_compress_arch);
+EXPORT_SYMBOL(blake2s_compress);
static int crypto_blake2s_update_x86(struct shash_desc *desc,
const u8 *in, unsigned int inlen)
{
- return crypto_blake2s_update(desc, in, inlen, blake2s_compress_arch);
+ return crypto_blake2s_update(desc, in, inlen, blake2s_compress);
}
static int crypto_blake2s_final_x86(struct shash_desc *desc, u8 *out)
{
- return crypto_blake2s_final(desc, out, blake2s_compress_arch);
+ return crypto_blake2s_final(desc, out, blake2s_compress);
}
#define BLAKE2S_ALG(name, driver_name, digest_size) \
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 285f82647d2b..bfda2c82774d 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -685,7 +685,6 @@ config CRYPTO_BLAKE2B
config CRYPTO_BLAKE2S
tristate "BLAKE2s digest algorithm"
- select CRYPTO_LIB_BLAKE2S_GENERIC
select CRYPTO_HASH
help
Implementation of cryptographic hash function BLAKE2s
@@ -702,10 +701,8 @@ config CRYPTO_BLAKE2S
See https://blake2.net for further information.
config CRYPTO_BLAKE2S_X86
- tristate "BLAKE2s digest algorithm (x86 accelerated version)"
+ bool "BLAKE2s digest algorithm (x86 accelerated version)"
depends on X86 && 64BIT
- select CRYPTO_LIB_BLAKE2S_GENERIC
- select CRYPTO_ARCH_HAVE_LIB_BLAKE2S
config CRYPTO_CRCT10DIF
tristate "CRCT10DIF algorithm"
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 6cccc3dc00bc..b2a4f998c180 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -81,7 +81,6 @@ config WIREGUARD
select CRYPTO
select CRYPTO_LIB_CURVE25519
select CRYPTO_LIB_CHACHA20POLY1305
- select CRYPTO_LIB_BLAKE2S
select CRYPTO_CHACHA20_X86_64 if X86 && 64BIT
select CRYPTO_POLY1305_X86_64 if X86 && 64BIT
select CRYPTO_BLAKE2S_X86 if X86 && 64BIT
diff --git a/include/crypto/internal/blake2s.h b/include/crypto/internal/blake2s.h
index 8e50d487500f..d39cfa0d333e 100644
--- a/include/crypto/internal/blake2s.h
+++ b/include/crypto/internal/blake2s.h
@@ -11,11 +11,11 @@
#include <crypto/internal/hash.h>
#include <linux/string.h>
-void blake2s_compress_generic(struct blake2s_state *state,const u8 *block,
+void blake2s_compress_generic(struct blake2s_state *state, const u8 *block,
size_t nblocks, const u32 inc);
-void blake2s_compress_arch(struct blake2s_state *state,const u8 *block,
- size_t nblocks, const u32 inc);
+void blake2s_compress(struct blake2s_state *state, const u8 *block,
+ size_t nblocks, const u32 inc);
bool blake2s_selftest(void);
diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig
index 545ccbddf6a1..31c6e2be3b84 100644
--- a/lib/crypto/Kconfig
+++ b/lib/crypto/Kconfig
@@ -8,31 +8,6 @@ config CRYPTO_LIB_AES
config CRYPTO_LIB_ARC4
tristate
-config CRYPTO_ARCH_HAVE_LIB_BLAKE2S
- tristate
- help
- Declares whether the architecture provides an arch-specific
- accelerated implementation of the Blake2s library interface,
- either builtin or as a module.
-
-config CRYPTO_LIB_BLAKE2S_GENERIC
- tristate
- help
- This symbol can be depended upon by arch implementations of the
- Blake2s library interface that require the generic code as a
- fallback, e.g., for SIMD implementations. If no arch specific
- implementation is enabled, this implementation serves the users
- of CRYPTO_LIB_BLAKE2S.
-
-config CRYPTO_LIB_BLAKE2S
- tristate "BLAKE2s hash function library"
- depends on CRYPTO_ARCH_HAVE_LIB_BLAKE2S || !CRYPTO_ARCH_HAVE_LIB_BLAKE2S
- select CRYPTO_LIB_BLAKE2S_GENERIC if CRYPTO_ARCH_HAVE_LIB_BLAKE2S=n
- help
- Enable the Blake2s library interface. This interface may be fulfilled
- by either the generic implementation or an arch-specific one, if one
- is available and enabled.
-
config CRYPTO_ARCH_HAVE_LIB_CHACHA
tristate
help
diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile
index 73205ed269ba..42e1d932c077 100644
--- a/lib/crypto/Makefile
+++ b/lib/crypto/Makefile
@@ -10,10 +10,9 @@ libaes-y := aes.o
obj-$(CONFIG_CRYPTO_LIB_ARC4) += libarc4.o
libarc4-y := arc4.o
-obj-$(CONFIG_CRYPTO_LIB_BLAKE2S_GENERIC) += libblake2s-generic.o
-libblake2s-generic-y += blake2s-generic.o
-
-obj-$(CONFIG_CRYPTO_LIB_BLAKE2S) += libblake2s.o
+# blake2s is used by the /dev/random driver which is always builtin
+lib-y += blake2s-generic.o
+obj-y += libblake2s.o
libblake2s-y += blake2s.o
obj-$(CONFIG_CRYPTO_LIB_CHACHA20POLY1305) += libchacha20poly1305.o
diff --git a/lib/crypto/blake2s-generic.c b/lib/crypto/blake2s-generic.c
index 04ff8df24513..75ccb3e633e6 100644
--- a/lib/crypto/blake2s-generic.c
+++ b/lib/crypto/blake2s-generic.c
@@ -37,7 +37,11 @@ static inline void blake2s_increment_counter(struct blake2s_state *state,
state->t[1] += (state->t[0] < inc);
}
-void blake2s_compress_generic(struct blake2s_state *state,const u8 *block,
+void blake2s_compress(struct blake2s_state *state, const u8 *block,
+ size_t nblocks, const u32 inc)
+ __weak __alias(blake2s_compress_generic);
+
+void blake2s_compress_generic(struct blake2s_state *state, const u8 *block,
size_t nblocks, const u32 inc)
{
u32 m[16];
diff --git a/lib/crypto/blake2s.c b/lib/crypto/blake2s.c
index 4055aa593ec4..93f2ae051370 100644
--- a/lib/crypto/blake2s.c
+++ b/lib/crypto/blake2s.c
@@ -16,12 +16,6 @@
#include <linux/init.h>
#include <linux/bug.h>
-#if IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S)
-# define blake2s_compress blake2s_compress_arch
-#else
-# define blake2s_compress blake2s_compress_generic
-#endif
-
void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
{
__blake2s_update(state, in, inlen, blake2s_compress);
--
2.34.1
