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authornagendra modadugu <ngm@google.com>2016-04-27 00:07:11 -0700
committerchrome-bot <chrome-bot@chromium.org>2016-05-31 23:58:31 -0700
commitaca616c551d635a9e3bcfd627b26cede69abb419 (patch)
tree64139b9eaf1a6123af43e4de7f7f991aff239f01
parentabe2a55191dbcdf8c92bfea64601b607471d75be (diff)
downloadchrome-ec-aca616c551d635a9e3bcfd627b26cede69abb419.tar.gz
CR50: port dcrypto/cr50 code to depend on third_party/cryptoc
Port SHA and P256 code to depend on third_party/cryptoc. Remove config options CONFIG_SHA1, and CONFIG_SHA256 as these are provided by third_party/cryptoc. Also remove unused config options CONFIG_SHA384, CONFIG_SHA512. Crypto functions prefixed by dcrypto_ (declared in internal.h ), DCRYPTO_ (declared in dcrypto.h) are implemented under chip/g/dcrypto, and otherwise are implemented under third_party/cryptoc. BRANCH=none BUG=chrome-os-partner:43025,chrome-os-partner:47524,chrome-os-partner:53782 TEST=all tests in test/tpm_test/tpmtest.py pass Change-Id: If7da02849aba9703573559370af5fae721d594fc Signed-off-by: nagendra modadugu <ngm@google.com> Reviewed-on: https://chromium-review.googlesource.com/340853 Commit-Ready: Nagendra Modadugu <ngm@google.com> Tested-by: Nagendra Modadugu <ngm@google.com> Reviewed-by: Nagendra Modadugu <ngm@google.com> Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Diffstat
-rw-r--r--board/cr50/board.c4
-rw-r--r--board/cr50/board.h2
-rw-r--r--board/cr50/build.mk4
-rw-r--r--board/cr50/tpm2/ecc.c18
-rw-r--r--board/cr50/tpm2/hash.c11
-rw-r--r--chip/g/build.mk33
-rw-r--r--chip/g/dcrypto/dcrypto.h46
-rw-r--r--chip/g/dcrypto/hkdf.c33
-rw-r--r--chip/g/dcrypto/hmac.c33
-rw-r--r--chip/g/dcrypto/internal.h114
-rw-r--r--chip/g/dcrypto/p256.c443
-rw-r--r--chip/g/dcrypto/p256_ec.c1338
-rw-r--r--chip/g/dcrypto/p256_ecdsa.c103
-rw-r--r--chip/g/dcrypto/p256_ecies.c36
-rw-r--r--chip/g/dcrypto/rsa.c65
-rw-r--r--chip/g/dcrypto/sha1.c79
-rw-r--r--chip/g/dcrypto/sha256.c83
-rw-r--r--chip/g/upgrade_fw.c5
-rw-r--r--include/config.h2
19 files changed, 231 insertions, 2221 deletions
diff --git a/board/cr50/board.c b/board/cr50/board.c
index 1513af2d6c..ab9ea947df 100644
--- a/board/cr50/board.c
+++ b/board/cr50/board.c
@@ -25,6 +25,8 @@
/* Define interrupt and gpio structs */
#include "gpio_list.h"
+#include "cryptoc/sha.h"
+
/*
* TODO: NV_MEMORY_SIZE is defined in 2 places. Here and in
* /src/third_party/tmp2/Implementation.h. This needs to be
@@ -209,7 +211,7 @@ void sys_rst_asserted(enum gpio_signal signal)
void nvmem_compute_sha(uint8_t *p_buf, int num_bytes,
uint8_t *p_sha, int sha_len)
{
- uint8_t sha1_digest[SHA1_DIGEST_SIZE];
+ uint8_t sha1_digest[SHA_DIGEST_SIZE];
/*
* Taking advantage of the built in dcrypto engine to generate
* a CRC-like value that can be used to validate contents of an
diff --git a/board/cr50/board.h b/board/cr50/board.h
index 0dc8f331ad..e9a9bfbe84 100644
--- a/board/cr50/board.h
+++ b/board/cr50/board.h
@@ -80,8 +80,6 @@
/* Include crypto stuff, both software and hardware. */
#define CONFIG_DCRYPTO
-#define CONFIG_SHA1
-#define CONFIG_SHA256
#ifndef __ASSEMBLER__
diff --git a/board/cr50/build.mk b/board/cr50/build.mk
index bd70e19e81..97b0584c7d 100644
--- a/board/cr50/build.mk
+++ b/board/cr50/build.mk
@@ -60,9 +60,11 @@ CPPFLAGS += -I$(abspath ./test)
# Make sure the context of the software sha256 implementation fits. If it ever
# increases, a compile time assert will fire in tpm2/hash.c.
-CFLAGS += -DUSER_MIN_HASH_STATE_SIZE=210
+CFLAGS += -DUSER_MIN_HASH_STATE_SIZE=112
# Configure TPM2 headers accordingly.
CFLAGS += -DEMBEDDED_MODE=1
+# Configure cryptoc headers to handle unaligned accesses.
+CFLAGS += -DSUPPORT_UNALIGNED=1
# Add dependencies on that library
$(out)/RW/ec.RW.elf $(out)/RW/ec.RW_B.elf: LDFLAGS_EXTRA += -L$(out)/tpm2 -ltpm2
diff --git a/board/cr50/tpm2/ecc.c b/board/cr50/tpm2/ecc.c
index bd86817917..e54a74dee7 100644
--- a/board/cr50/tpm2/ecc.c
+++ b/board/cr50/tpm2/ecc.c
@@ -10,8 +10,12 @@
#include "TPMB.h"
#include "trng.h"
+#include "util.h"
#include "dcrypto.h"
+#include "cryptoc/p256.h"
+#include "cryptoc/p256_ecdsa.h"
+
static void reverse_tpm2b(TPM2B *b)
{
reverse(b->buffer, b->size);
@@ -42,8 +46,8 @@ BOOL _cpri__EccIsPointOnCurve(TPM_ECC_CURVE curve_id, TPMS_ECC_POINT *q)
reverse_tpm2b(&q->x.b);
reverse_tpm2b(&q->y.b);
- result = DCRYPTO_p256_valid_point((p256_int *) q->x.b.buffer,
- (p256_int *) q->y.b.buffer);
+ result = p256_is_valid_point((p256_int *) q->x.b.buffer,
+ (p256_int *) q->y.b.buffer);
reverse_tpm2b(&q->x.b);
reverse_tpm2b(&q->y.b);
@@ -198,10 +202,10 @@ CRYPT_RESULT _cpri__SignEcc(
reverse_tpm2b(&d->b);
- DCRYPTO_p256_ecdsa_sign((p256_int *) d->b.buffer,
- &p256_digest,
- (p256_int *) r->b.buffer,
- (p256_int *) s->b.buffer);
+ p256_ecdsa_sign((p256_int *) d->b.buffer,
+ &p256_digest,
+ (p256_int *) r->b.buffer,
+ (p256_int *) s->b.buffer);
reverse_tpm2b(&d->b);
r->b.size = sizeof(p256_int);
@@ -242,7 +246,7 @@ CRYPT_RESULT _cpri__ValidateSignatureEcc(
reverse_tpm2b(&r->b);
reverse_tpm2b(&s->b);
- result = DCRYPTO_p256_ecdsa_verify(
+ result = p256_ecdsa_verify(
(p256_int *) q->x.b.buffer,
(p256_int *) q->y.b.buffer,
&p256_digest,
diff --git a/board/cr50/tpm2/hash.c b/board/cr50/tpm2/hash.c
index cf057958f8..a11fb9e450 100644
--- a/board/cr50/tpm2/hash.c
+++ b/board/cr50/tpm2/hash.c
@@ -42,6 +42,7 @@ uint16_t _cpri__GetHashBlockSize(TPM_ALG_ID alg)
return lookup_hash_info(alg)->blockSize;
}
+BUILD_ASSERT(sizeof(LITE_SHA256_CTX) == USER_MIN_HASH_STATE_SIZE);
BUILD_ASSERT(sizeof(CPRI_HASH_STATE) == sizeof(EXPORT_HASH_STATE));
void _cpri__ImportExportHashState(CPRI_HASH_STATE *osslFmt,
EXPORT_HASH_STATE *externalFmt,
@@ -99,11 +100,11 @@ uint16_t _cpri__StartHash(TPM_ALG_ID alg, BOOL sequence,
switch (alg) {
case TPM_ALG_SHA1:
DCRYPTO_SHA1_init(ctx, sequence);
- result = DCRYPTO_HASH_size(ctx);
+ result = HASH_size(ctx);
break;
case TPM_ALG_SHA256:
DCRYPTO_SHA256_init(ctx, sequence);
- result = DCRYPTO_HASH_size(ctx);
+ result = HASH_size(ctx);
break;
/* TODO: add support for SHA384 and SHA512
* case TPM_ALG_SHA384:
@@ -128,7 +129,7 @@ void _cpri__UpdateHash(CPRI_HASH_STATE *state, uint32_t in_len,
{
struct HASH_CTX *ctx = (struct HASH_CTX *) state->state;
- DCRYPTO_HASH_update(ctx, in, in_len);
+ HASH_update(ctx, in, in_len);
}
uint16_t _cpri__CompleteHash(CPRI_HASH_STATE *state,
@@ -136,8 +137,8 @@ uint16_t _cpri__CompleteHash(CPRI_HASH_STATE *state,
{
struct HASH_CTX *ctx = (struct HASH_CTX *) state->state;
- out_len = MIN(DCRYPTO_HASH_size(ctx), out_len);
- memcpy(out, DCRYPTO_HASH_final(ctx), out_len);
+ out_len = MIN(HASH_size(ctx), out_len);
+ memcpy(out, HASH_final(ctx), out_len);
return out_len;
}
diff --git a/chip/g/build.mk b/chip/g/build.mk
index 8161966d4e..09333669ca 100644
--- a/chip/g/build.mk
+++ b/chip/g/build.mk
@@ -17,6 +17,16 @@ ver_params := $(shell echo "$(ver_defs) $(bld_defs)" | $(CPP) $(CPPFLAGS) -P \
ver_str := $(shell printf "%s%s %d_%d" $(ver_params))
CPPFLAGS+= -DGC_REVISION="$(ver_str)"
+ifeq ($(CONFIG_DCRYPTO),y)
+INCLUDE_ROOT := $(abspath ./include)
+CRYPTOCLIB := $(realpath ../../third_party/cryptoc)
+CPPFLAGS += -I$(abspath .)
+CPPFLAGS += -I$(abspath ./builtin)
+CPPFLAGS += -I$(abspath ./chip/$(CHIP))
+CPPFLAGS += -I$(INCLUDE_ROOT)
+CPPFLAGS += -I$(CRYPTOCLIB)/include
+endif
+
# Required chip modules
chip-y=clock.o gpio.o hwtimer.o jtag.o system.o
ifeq ($(CONFIG_POLLING_UART),y)
@@ -32,7 +42,6 @@ chip-$(CONFIG_DCRYPTO)+= dcrypto/hmac.o
chip-$(CONFIG_DCRYPTO)+= dcrypto/hkdf.o
chip-$(CONFIG_DCRYPTO)+= dcrypto/p256.o
chip-$(CONFIG_DCRYPTO)+= dcrypto/p256_ec.o
-chip-$(CONFIG_DCRYPTO)+= dcrypto/p256_ecdsa.o
chip-$(CONFIG_DCRYPTO)+= dcrypto/p256_ecies.o
chip-$(CONFIG_DCRYPTO)+= dcrypto/rsa.o
chip-$(CONFIG_DCRYPTO)+= dcrypto/sha1.o
@@ -96,3 +105,25 @@ $(out)/RW/ec.RW_B.flat: $(out)/util/signer
endif
CR50_RO_KEY ?= rom-testkey-A.pem
+
+# This file is included twice by the Makefile, once to determine the CHIP info
+# # and then again after defining all the CONFIG_ and HAS_TASK variables. We use
+# # a guard so that recipe definitions and variable extensions only happen the
+# # second time.
+ifeq ($(CHIP_MK_INCLUDED_ONCE),)
+CHIP_MK_INCLUDED_ONCE=1
+else
+
+ifeq ($(CONFIG_DCRYPTO),y)
+$(out)/RW/ec.RW.elf $(out)/RW/ec.RW_B.elf: LDFLAGS_EXTRA += -L$(out)/cryptoc \
+ -lcryptoc
+$(out)/RW/ec.RW.elf $(out)/RW/ec.RW_B.elf: $(out)/cryptoc/libcryptoc.a
+
+# Force the external build each time, so it can look for changed sources.
+.PHONY: $(out)/cryptoc/libcryptoc.a
+$(out)/cryptoc/libcryptoc.a:
+ $(MAKE) obj=$(realpath $(out))/cryptoc SUPPORT_UNALIGNED=1 \
+ -C $(CRYPTOCLIB)
+endif # end CONFIG_DCRYPTO
+
+endif # CHIP_MK_INCLUDED_ONCE is nonempty
diff --git a/chip/g/dcrypto/dcrypto.h b/chip/g/dcrypto/dcrypto.h
index de30eecaf0..ed033c16e2 100644
--- a/chip/g/dcrypto/dcrypto.h
+++ b/chip/g/dcrypto/dcrypto.h
@@ -14,6 +14,10 @@
#include "internal.h"
+#include <stddef.h>
+
+#include "cryptoc/hmac.h"
+
enum cipher_mode {
CIPHER_MODE_ECB = 0,
CIPHER_MODE_CTR = 1,
@@ -26,27 +30,11 @@ enum encrypt_mode {
ENCRYPT_MODE = 1
};
-struct HASH_CTX; /* Forward declaration. */
-
-typedef struct HASH_CTX SHA1_CTX;
-typedef struct HASH_CTX SHA256_CTX;
-
enum hashing_mode {
HASH_SHA1 = 0,
HASH_SHA256 = 1
};
-#define DCRYPTO_HASH_update(ctx, data, len) \
- ((ctx)->vtab->update((ctx), (data), (len)))
-#define DCRYPTO_HASH_final(ctx) \
- ((ctx)->vtab->final((ctx)))
-#define DCRYPTO_HASH_size(ctx) \
- ((ctx)->vtab->size)
-
-#define DCRYPTO_SHA1_update(ctx, data, n) \
- DCRYPTO_HASH_update((ctx), (data), (n))
-#define DCRYPTO_SHA1_final(ctx) DCRYPTO_HASH_final((ctx))
-
/*
* AES implementation, based on a hardware AES block.
*/
@@ -68,18 +56,21 @@ int DCRYPTO_aes_ctr(uint8_t *out, const uint8_t *key, uint32_t key_bits,
* is TRUE, in which case there will be no attempt to use the hardware for
* this particular hashing session.
*/
-void DCRYPTO_SHA1_init(SHA1_CTX *ctx, uint32_t sw_required);
-void DCRYPTO_SHA256_init(SHA256_CTX *ctx, uint32_t sw_required);
-const uint8_t *DCRYPTO_SHA1_hash(const uint8_t *data, uint32_t n,
+void DCRYPTO_SHA1_init(SHA_CTX *ctx, uint32_t sw_required);
+void DCRYPTO_SHA256_init(LITE_SHA256_CTX *ctx, uint32_t sw_required);
+const uint8_t *DCRYPTO_SHA1_hash(const void *data, uint32_t n,
uint8_t *digest);
-
-#define DCRYPTO_SHA256_update(ctx, data, n) \
- DCRYPTO_HASH_update((ctx), (data), (n))
-#define DCRYPTO_SHA256_final(ctx) DCRYPTO_HASH_final((ctx))
-const uint8_t *DCRYPTO_SHA256_hash(const uint8_t *data, uint32_t n,
+const uint8_t *DCRYPTO_SHA256_hash(const void *data, uint32_t n,
uint8_t *digest);
/*
+ * HMAC.
+ */
+void DCRYPTO_HMAC_SHA256_init(LITE_HMAC_CTX *ctx, const void *key,
+ unsigned int len);
+const uint8_t *DCRYPTO_HMAC_final(LITE_HMAC_CTX *ctx);
+
+/*
* BIGNUM utility methods.
*/
void DCRYPTO_bn_wrap(struct BIGNUM *b, void *buf, size_t len);
@@ -137,7 +128,6 @@ int DCRYPTO_rsa_key_compute(struct BIGNUM *N, struct BIGNUM *d,
/*
* EC.
*/
-int DCRYPTO_p256_valid_point(const p256_int *x, const p256_int *y);
int DCRYPTO_p256_base_point_mul(p256_int *out_x, p256_int *out_y,
const p256_int *n);
int DCRYPTO_p256_point_mul(p256_int *out_x, p256_int *out_y,
@@ -145,12 +135,6 @@ int DCRYPTO_p256_point_mul(p256_int *out_x, p256_int *out_y,
const p256_int *in_y);
int DCRYPTO_p256_key_from_bytes(p256_int *x, p256_int *y, p256_int *d,
const uint8_t key_bytes[P256_NBYTES]);
-
-void DCRYPTO_p256_ecdsa_sign(const p256_int *d, const p256_int *digest,
- p256_int *r, p256_int *s);
-int DCRYPTO_p256_ecdsa_verify(const p256_int *key_x, const p256_int *key_y,
- const p256_int *digest, const p256_int *r,
- const p256_int *s);
/* P256 based integration encryption (DH+AES128+SHA256). */
/* Authenticated data may be provided, where the first auth_data_len
* bytes of in will be authenticated but not encrypted. */
diff --git a/chip/g/dcrypto/hkdf.c b/chip/g/dcrypto/hkdf.c
index db861ec318..9a647361ce 100644
--- a/chip/g/dcrypto/hkdf.c
+++ b/chip/g/dcrypto/hkdf.c
@@ -7,10 +7,12 @@
#include "dcrypto.h"
#include "internal.h"
+#include "cryptoc/sha256.h"
+
static int hkdf_extract(uint8_t *PRK, const uint8_t *salt, size_t salt_len,
const uint8_t *IKM, size_t IKM_len)
{
- struct HMAC_CTX ctx;
+ LITE_HMAC_CTX ctx;
if (PRK == NULL)
return 0;
@@ -19,9 +21,9 @@ static int hkdf_extract(uint8_t *PRK, const uint8_t *salt, size_t salt_len,
if (IKM == NULL && IKM_len > 0)
return 0;
- dcrypto_HMAC_SHA256_init(&ctx, salt, salt_len);
- dcrypto_HMAC_update(&ctx, IKM, IKM_len);
- memcpy(PRK, dcrypto_HMAC_final(&ctx), SHA256_DIGEST_BYTES);
+ DCRYPTO_HMAC_SHA256_init(&ctx, salt, salt_len);
+ HASH_update(&ctx.hash, IKM, IKM_len);
+ memcpy(PRK, DCRYPTO_HMAC_final(&ctx), SHA256_DIGEST_SIZE);
return 1;
}
@@ -31,8 +33,8 @@ static int hkdf_expand(uint8_t *OKM, size_t OKM_len, const uint8_t *PRK,
uint8_t count = 1;
const uint8_t *T = OKM;
size_t T_len = 0;
- uint32_t num_blocks = (OKM_len / SHA256_DIGEST_BYTES) +
- (OKM_len % SHA256_DIGEST_BYTES ? 1 : 0);
+ uint32_t num_blocks = (OKM_len / SHA256_DIGEST_SIZE) +
+ (OKM_len % SHA256_DIGEST_SIZE ? 1 : 0);
if (OKM == NULL || OKM_len == 0)
return 0;
@@ -44,17 +46,18 @@ static int hkdf_expand(uint8_t *OKM, size_t OKM_len, const uint8_t *PRK,
return 0;
while (OKM_len > 0) {
- struct HMAC_CTX ctx;
- const size_t block_size = MIN(OKM_len, SHA256_DIGEST_BYTES);
+ LITE_HMAC_CTX ctx;
+ const size_t block_size = OKM_len < SHA256_DIGEST_SIZE ?
+ OKM_len : SHA256_DIGEST_SIZE;
- dcrypto_HMAC_SHA256_init(&ctx, PRK, SHA256_DIGEST_BYTES);
- dcrypto_HMAC_update(&ctx, T, T_len);
- dcrypto_HMAC_update(&ctx, info, info_len);
- dcrypto_HMAC_update(&ctx, &count, sizeof(count));
- memcpy(OKM, dcrypto_HMAC_final(&ctx), block_size);
+ DCRYPTO_HMAC_SHA256_init(&ctx, PRK, SHA256_DIGEST_SIZE);
+ HASH_update(&ctx.hash, T, T_len);
+ HASH_update(&ctx.hash, info, info_len);
+ HASH_update(&ctx.hash, &count, sizeof(count));
+ memcpy(OKM, DCRYPTO_HMAC_final(&ctx), block_size);
T += T_len;
- T_len = SHA256_DIGEST_BYTES;
+ T_len = SHA256_DIGEST_SIZE;
count += 1;
OKM += block_size;
OKM_len -= block_size;
@@ -68,7 +71,7 @@ int DCRYPTO_hkdf(uint8_t *OKM, size_t OKM_len,
const uint8_t *info, size_t info_len)
{
int result;
- uint8_t PRK[SHA256_DIGEST_BYTES];
+ uint8_t PRK[SHA256_DIGEST_SIZE];
if (!hkdf_extract(PRK, salt, salt_len, IKM, IKM_len))
return 0;
diff --git a/chip/g/dcrypto/hmac.c b/chip/g/dcrypto/hmac.c
index 1b6a820159..1c34ddfd96 100644
--- a/chip/g/dcrypto/hmac.c
+++ b/chip/g/dcrypto/hmac.c
@@ -3,12 +3,15 @@
* found in the LICENSE file.
*/
-#include <stdint.h>
-
#include "internal.h"
#include "dcrypto.h"
-static void HMAC_init(struct HMAC_CTX *ctx, const void *key, unsigned int len)
+#include <stdint.h>
+
+#include "cryptoc/sha256.h"
+
+/* TODO(ngm): add support for hardware hmac. */
+static void HMAC_init(LITE_HMAC_CTX *ctx, const void *key, unsigned int len)
{
unsigned int i;
@@ -16,9 +19,9 @@ static void HMAC_init(struct HMAC_CTX *ctx, const void *key, unsigned int len)
if (len > sizeof(ctx->opad)) {
DCRYPTO_SHA256_init(&ctx->hash, 0);
- DCRYPTO_HASH_update(&ctx->hash, key, len);
- memcpy(&ctx->opad[0], DCRYPTO_HASH_final(&ctx->hash),
- DCRYPTO_HASH_size(&ctx->hash));
+ HASH_update(&ctx->hash, key, len);
+ memcpy(&ctx->opad[0], HASH_final(&ctx->hash),
+ HASH_size(&ctx->hash));
} else {
memcpy(&ctx->opad[0], key, len);
}
@@ -28,29 +31,29 @@ static void HMAC_init(struct HMAC_CTX *ctx, const void *key, unsigned int len)
DCRYPTO_SHA256_init(&ctx->hash, 0);
/* hash ipad */
- DCRYPTO_HASH_update(&ctx->hash, ctx->opad, sizeof(ctx->opad));
+ HASH_update(&ctx->hash, ctx->opad, sizeof(ctx->opad));
for (i = 0; i < sizeof(ctx->opad); ++i)
ctx->opad[i] ^= (0x36 ^ 0x5c);
}
-void dcrypto_HMAC_SHA256_init(struct HMAC_CTX *ctx, const void *key,
+void DCRYPTO_HMAC_SHA256_init(LITE_HMAC_CTX *ctx, const void *key,
unsigned int len)
{
DCRYPTO_SHA256_init(&ctx->hash, 0);
HMAC_init(ctx, key, len);
}
-const uint8_t *dcrypto_HMAC_final(struct HMAC_CTX *ctx)
+const uint8_t *DCRYPTO_HMAC_final(LITE_HMAC_CTX *ctx)
{
uint8_t digest[SHA_DIGEST_MAX_BYTES]; /* upto SHA2 */
- memcpy(digest, DCRYPTO_HASH_final(&ctx->hash),
- (DCRYPTO_HASH_size(&ctx->hash) <= sizeof(digest) ?
- DCRYPTO_HASH_size(&ctx->hash) : sizeof(digest)));
+ memcpy(digest, HASH_final(&ctx->hash),
+ (HASH_size(&ctx->hash) <= sizeof(digest) ?
+ HASH_size(&ctx->hash) : sizeof(digest)));
DCRYPTO_SHA256_init(&ctx->hash, 0);
- DCRYPTO_HASH_update(&ctx->hash, ctx->opad, sizeof(ctx->opad));
- DCRYPTO_HASH_update(&ctx->hash, digest, DCRYPTO_HASH_size(&ctx->hash));
+ HASH_update(&ctx->hash, ctx->opad, sizeof(ctx->opad));
+ HASH_update(&ctx->hash, digest, HASH_size(&ctx->hash));
memset(&ctx->opad[0], 0, sizeof(ctx->opad)); /* wipe key */
- return DCRYPTO_HASH_final(&ctx->hash);
+ return HASH_final(&ctx->hash);
}
diff --git a/chip/g/dcrypto/internal.h b/chip/g/dcrypto/internal.h
index 09a1e09031..1173e018e1 100644
--- a/chip/g/dcrypto/internal.h
+++ b/chip/g/dcrypto/internal.h
@@ -6,11 +6,15 @@
#ifndef __EC_CHIP_G_DCRYPTO_INTERNAL_H
#define __EC_CHIP_G_DCRYPTO_INTERNAL_H
-#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
#include "common.h"
-#include "sha1.h"
-#include "sha256.h"
+#include "util.h"
+
+#include "cryptoc/p256.h"
+#include "cryptoc/sha.h"
+#include "cryptoc/sha256.h"
/*
* SHA.
@@ -20,43 +24,10 @@
#define CTRL_ENCRYPT 1
#define CTRL_NO_SOFT_RESET 0
-struct HASH_CTX; /* Forward declaration. */
-
-struct HASH_VTAB {
- void (* const update)(struct HASH_CTX *, const uint8_t *, uint32_t);
- const uint8_t *(* const final)(struct HASH_CTX *);
- const uint8_t *(* const hash)(const uint8_t *, uint32_t, uint8_t *);
- uint32_t size;
-};
+#define SHA_DIGEST_WORDS (SHA_DIGEST_SIZE / sizeof(uint32_t))
+#define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / sizeof(uint32_t))
-#define SHA1_DIGEST_BYTES 20
-#define SHA256_DIGEST_BYTES 32
-#define SHA384_DIGEST_BYTES 48
-#define SHA512_DIGEST_BYTES 64
-
-#define SHA1_DIGEST_WORDS (SHA1_DIGEST_BYTES / sizeof(uint32_t))
-#define SHA256_DIGEST_WORDS (SHA256_DIGEST_BYTES / sizeof(uint32_t))
-#define SHA384_DIGEST_WORDS (SHA384_DIGEST_BYTES / sizeof(uint32_t))
-#define SHA512_DIGEST_WORDS (SHA512_DIGEST_BYTES / sizeof(uint32_t))
-
-#if defined(CONFIG_SHA512)
-#define SHA_DIGEST_MAX_BYTES SHA512_DIGEST_BYTES
-#elif defined(CONFIG_SHA384)
-#define SHA_DIGEST_MAX_BYTES SHA384_DIGEST_BYTES
-#elif defined(CONFIG_SHA256)
-#define SHA_DIGEST_MAX_BYTES SHA256_DIGEST_BYTES
-#elif defined CONFIG_SHA1
-#define SHA_DIGEST_MAX_BYTES SHA1_DIGEST_BYTES
-#endif
-
-struct HASH_CTX {
- const struct HASH_VTAB *vtab;
- union {
- uint8_t buf[SHA_DIGEST_MAX_BYTES];
- struct sha1_ctx sw_sha1;
- struct sha256_ctx sw_sha256;
- } u;
-};
+#define SHA_DIGEST_MAX_BYTES SHA256_DIGEST_SIZE
enum sha_mode {
SHA1_MODE = 0,
@@ -79,25 +50,10 @@ void dcrypto_sha_hash(enum sha_mode mode, const uint8_t *data,
uint32_t n, uint8_t *digest);
void dcrypto_sha_init(enum sha_mode mode);
void dcrypto_sha_update(struct HASH_CTX *unused,
- const uint8_t *data, uint32_t n);
+ const void *data, uint32_t n);
void dcrypto_sha_wait(enum sha_mode mode, uint32_t *digest);
/*
- * HMAC.
- */
-struct HMAC_CTX {
- struct HASH_CTX hash;
- uint8_t opad[64];
-};
-
-#define HASH_update(ctx, data, len) \
- ((ctx)->vtab->update((ctx), (data), (len)))
-void dcrypto_HMAC_SHA256_init(struct HMAC_CTX *ctx, const void *key,
- unsigned int len);
-#define dcrypto_HMAC_update(ctx, data, len) HASH_update(&(ctx)->hash, data, len)
-const uint8_t *dcrypto_HMAC_final(struct HMAC_CTX *ctx);
-
-/*
* BIGNUM.
*/
#define BN_BITS2 32
@@ -123,54 +79,6 @@ int bn_modinv_vartime(struct BIGNUM *r, const struct BIGNUM *e,
const struct BIGNUM *MOD);
/*
- * EC.
- */
-#define P256_BITSPERDIGIT 32
-#define P256_NDIGITS 8
-#define P256_NBYTES 32
-
-typedef uint32_t p256_digit;
-typedef int32_t p256_sdigit;
-typedef uint64_t p256_ddigit;
-typedef int64_t p256_sddigit;
-
-/* Define p256_int as a struct to leverage struct assignment. */
-typedef struct {
- p256_digit a[P256_NDIGITS] __packed;
-} p256_int;
-
-#define P256_DIGITS(x) ((x)->a)
-#define P256_DIGIT(x, y) ((x)->a[y])
-
-#define P256_ZERO { {0} }
-#define P256_ONE { {1} }
-
-/* Curve constants. */
-extern const p256_int SECP256r1_n;
-extern const p256_int SECP256r1_p;
-extern const p256_int SECP256r1_b;
-
-void p256_init(p256_int *a);
-void p256_from_bin(const uint8_t src[P256_NBYTES], p256_int *dst);
-void p256_to_bin(const p256_int *src, uint8_t dst[P256_NBYTES]);
-#define p256_clear(a) p256_init((a))
-int p256_is_zero(const p256_int *a);
-int p256_cmp(const p256_int *a, const p256_int *b);
-int p256_get_bit(const p256_int *scalar, int bit);
-p256_digit p256_shl(const p256_int *a, int n, p256_int *b);
-void p256_shr(const p256_int *a, int n, p256_int *b);
-int p256_add(const p256_int *a, const p256_int *b, p256_int *c);
-int p256_add_d(const p256_int *a, p256_digit d, p256_int *b);
-void p256_points_mul_vartime(
- const p256_int *n1, const p256_int *n2, const p256_int *in_x,
- const p256_int *in_y, p256_int *out_x, p256_int *out_y);
-void p256_mod(const p256_int *MOD, const p256_int *in, p256_int *out);
-void p256_modmul(const p256_int *MOD, const p256_int *a,
- const p256_digit top_b, const p256_int *b, p256_int *c);
-void p256_modinv(const p256_int *MOD, const p256_int *a, p256_int *b);
-void p256_modinv_vartime(const p256_int *MOD, const p256_int *a, p256_int *b);
-
-/*
* Utility functions.
*/
/* TODO(ngm): memset that doesn't get optimized out. */
diff --git a/chip/g/dcrypto/p256.c b/chip/g/dcrypto/p256.c
index 02e00b890b..cb963bb669 100644
--- a/chip/g/dcrypto/p256.c
+++ b/chip/g/dcrypto/p256.c
@@ -4,442 +4,11 @@
*/
#include "dcrypto.h"
-#include "internal.h"
-#include <assert.h>
+#include "cryptoc/p256.h"
-const p256_int SECP256r1_n = /* curve order */
- { {0xfc632551, 0xf3b9cac2, 0xa7179e84, 0xbce6faad, -1, -1, 0, -1} };
-static const p256_int SECP256r1_nMin2 = /* curve order - 2 */
- { {0xfc632551 - 2, 0xf3b9cac2, 0xa7179e84, 0xbce6faad, -1, -1, 0, -1} };
-const p256_int SECP256r1_p = /* curve field size */
- { {-1, -1, -1, 0, 0, 0, 1, -1 } };
-const p256_int SECP256r1_b = /* curve b */
- { {0x27d2604b, 0x3bce3c3e, 0xcc53b0f6, 0x651d06b0,
- 0x769886bc, 0xb3ebbd55, 0xaa3a93e7, 0x5ac635d8} };
static const p256_int p256_one = P256_ONE;
-void p256_init(p256_int *a)
-{
- memset(a, 0, sizeof(*a));
-}
-
-int p256_get_bit(const p256_int *scalar, int bit)
-{
- return (P256_DIGIT(scalar, bit / P256_BITSPERDIGIT)
- >> (bit & (P256_BITSPERDIGIT - 1))) & 1;
-}
-
-p256_digit p256_shl(const p256_int *a, int n, p256_int *b)
-{
- int i;
- p256_digit top = P256_DIGIT(a, P256_NDIGITS - 1);
-
- n %= P256_BITSPERDIGIT;
- for (i = P256_NDIGITS - 1; i > 0; --i) {
- p256_digit accu = (P256_DIGIT(a, i) << n);
-
- accu |= (P256_DIGIT(a, i - 1) >> (P256_BITSPERDIGIT - n));
- P256_DIGIT(b, i) = accu;
- }
- P256_DIGIT(b, i) = (P256_DIGIT(a, i) << n);
-
- top >>= (P256_BITSPERDIGIT - n);
-
- return top;
-}
-
-void p256_shr(const p256_int *a, int n, p256_int *b)
-{
- int i;
-
- n %= P256_BITSPERDIGIT;
- for (i = 0; i < P256_NDIGITS - 1; ++i) {
- p256_digit accu = (P256_DIGIT(a, i) >> n);
-
- accu |= (P256_DIGIT(a, i + 1) << (P256_BITSPERDIGIT - n));
- P256_DIGIT(b, i) = accu;
- }
- P256_DIGIT(b, i) = (P256_DIGIT(a, i) >> n);
-}
-
-int p256_is_zero(const p256_int *a)
-{
- int i, result = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i)
- result |= P256_DIGIT(a, i);
- return !result;
-}
-
-int p256_cmp(const p256_int *a, const p256_int *b)
-{
- int i;
- p256_sddigit borrow = 0;
- p256_digit notzero = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- borrow += (p256_sddigit) P256_DIGIT(a, i) - P256_DIGIT(b, i);
- /* Track whether any result digit is ever not zero.
- * Relies on !!(non-zero) evaluating to 1, e.g., !!(-1)
- * evaluating to 1. */
- notzero |= !!((p256_digit) borrow);
- borrow >>= P256_BITSPERDIGIT;
- }
- return (int) borrow | notzero;
-}
-
-/* c = a - b. Returns borrow: 0 or -1. */
-int p256_sub(const p256_int *a, const p256_int *b, p256_int *c)
-{
- int i;
- p256_sddigit borrow = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- borrow += (p256_sddigit) P256_DIGIT(a, i) - P256_DIGIT(b, i);
- if (c)
- P256_DIGIT(c, i) = (p256_digit) borrow;
- borrow >>= P256_BITSPERDIGIT;
- }
- return (int) borrow;
-}
-
-/* c = a + b. Returns carry: 0 or 1. */
-int p256_add(const p256_int *a, const p256_int *b, p256_int *c)
-{
- int i;
- p256_ddigit carry = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- carry += (p256_ddigit) P256_DIGIT(a, i) + P256_DIGIT(b, i);
- if (c)
- P256_DIGIT(c, i) = (p256_digit) carry;
- carry >>= P256_BITSPERDIGIT;
- }
- return (int) carry;
-}
-
-/* b = a + d. Returns carry, 0 or 1. */
-int p256_add_d(const p256_int *a, p256_digit d, p256_int *b)
-{
- int i;
- p256_ddigit carry = d;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- carry += (p256_ddigit) P256_DIGIT(a, i);
- if (b)
- P256_DIGIT(b, i) = (p256_digit) carry;
- carry >>= P256_BITSPERDIGIT;
- }
- return (int) carry;
-}
-
-/* top, c[] += a[] * b */
-/* Returns new top. */
-static p256_digit p256_muladd(const p256_int *a, p256_digit b,
- p256_digit top, p256_digit *c)
-{
- int i;
- p256_ddigit carry = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- carry += *c;
- carry += (p256_ddigit) P256_DIGIT(a, i) * b;
- *c++ = (p256_digit) carry;
- carry >>= P256_BITSPERDIGIT;
- }
- return top + (p256_digit) carry;
-}
-
-/* top, c[] -= top_a, a[] */
-static p256_digit p256_subtop(p256_digit top_a, const p256_digit *a,
- p256_digit top_c, p256_digit *c)
-{
- int i;
- p256_sddigit borrow = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- borrow += *c;
- borrow -= *a++;
- *c++ = (p256_digit) borrow;
- borrow >>= P256_BITSPERDIGIT;
- }
- borrow += top_c;
- borrow -= top_a;
- top_c = (p256_digit) borrow;
- assert((borrow >> P256_BITSPERDIGIT) == 0);
- return top_c;
-}
-
-/* top, c[] += MOD[] & mask (0 or -1) */
-/* returns new top. */
-static p256_digit p256_addM(const p256_int *MOD, p256_digit top,
- p256_digit *c, p256_digit mask)
-{
- int i;
- p256_ddigit carry = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- carry += *c;
- carry += P256_DIGIT(MOD, i) & mask;
- *c++ = (p256_digit) carry;
- carry >>= P256_BITSPERDIGIT;
- }
- return top + (p256_digit) carry;
-}
-
-/* top, c[] -= MOD[] & mask (0 or -1) */
-/* returns new top. */
-static p256_digit p256_subM(const p256_int *MOD, p256_digit top,
- p256_digit *c, p256_digit mask)
-{
- int i;
- p256_sddigit borrow = 0;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- borrow += *c;
- borrow -= P256_DIGIT(MOD, i) & mask;
- *c++ = (p256_digit) borrow;
- borrow >>= P256_BITSPERDIGIT;
- }
- return top + (p256_digit) borrow;
-}
-
-/* Convert in. */
-void p256_from_bin(const uint8_t src[P256_NBYTES], p256_int *dst)
-{
- int i;
- const uint8_t *p = &src[0];
-
- for (i = P256_NDIGITS - 1; i >= 0; --i) {
- P256_DIGIT(dst, i) =
- (p[0] << 24) |
- (p[1] << 16) |
- (p[2] << 8) |
- p[3];
- p += 4;
- }
-}
-
-/* Convert out. */
-void p256_to_bin(const p256_int *src, uint8_t dst[P256_NBYTES])
-{
- int i;
- uint8_t *p = &dst[0];
-
- for (i = P256_NDIGITS - 1; i >= 0; --i) {
- p256_digit d = P256_DIGIT(src, i);
-
- p[0] = (d >> 24) & 0xFF;
- p[1] = (d >> 16) & 0xFF;
- p[2] = (d >> 8) & 0xFF;
- p[3] = d & 0xFF;
- p += 4;
- }
-}
-
-void p256_mod(const p256_int *MOD, const p256_int *in, p256_int *out)
-{
- if (out != in)
- *out = *in;
- p256_addM(MOD, 0, P256_DIGITS(out),
- p256_subM(MOD, 0, P256_DIGITS(out), -1));
-}
-
-
-void p256_modmul(const p256_int *MOD, const p256_int *a,
- const p256_digit top_b, const p256_int *b, p256_int *c)
-{
- p256_digit tmp[P256_NDIGITS * 2 + 1] = { 0 };
- p256_digit top = 0;
- int i;
-
- /* Multiply/add into tmp. */
- for (i = 0; i < P256_NDIGITS; ++i) {
- if (i)
- tmp[i + P256_NDIGITS - 1] = top;
- top = p256_muladd(a, P256_DIGIT(b, i), 0, tmp + i);
- }
-
- /* Multiply/add top digit. */
- tmp[i + P256_NDIGITS - 1] = top;
- top = p256_muladd(a, top_b, 0, tmp + i);
-
- /* Reduce tmp, digit by digit. */
- for (; i >= 0; --i) {
- p256_digit reducer[P256_NDIGITS] = { 0 };
- p256_digit top_reducer;
-
- /* top can be any value at this point.
- * Guestimate reducer as top * MOD, since msw of MOD is -1. */
- top_reducer = p256_muladd(MOD, top, 0, reducer);
-
- /* Subtract reducer from top | tmp. */
- top = p256_subtop(top_reducer, reducer, top, tmp + i);
-
- /* top is now either 0 or 1. Make it 0, fixed-timing. */
- assert(top <= 1);
-
- top = p256_subM(MOD, top, tmp + i, ~(top - 1));
-
- assert(top == 0);
-
- /* We have now reduced the top digit off tmp. Fetch
- * new top digit. */
- top = tmp[i + P256_NDIGITS - 1];
- }
-
- /* tmp might still be larger than MOD, yet same bit length.
- * Make sure it is less, fixed-timing. */
- p256_addM(MOD, 0, tmp, p256_subM(MOD, 0, tmp, -1));
-
- memcpy(c, tmp, P256_NBYTES);
-}
-
-/* if (mask) dst = src, fixed-timing style. */
-static void conditional_copy(const p256_int *src, p256_int *dst, int mask)
-{
- int i;
-
- for (i = 0; i < P256_NDIGITS; ++i) {
- p256_digit b = P256_DIGIT(src, i) & mask; /* 0 or src[i] */
-
- b |= P256_DIGIT(dst, i) & ~mask; /* dst[i] or 0 */
- P256_DIGIT(dst, i) = b;
- }
-}
-
-/* -1 iff (x & 15) == 0, 0 otherwise. */
-/* Relies on arithmetic shift right behavior. */
-#define ZEROtoONES(x) (((int32_t)(((x) & 15) - 1)) >> 31)
-
-/* tbl[0] = tbl[idx], fixed-timing style. */
-static void set0ToIdx(p256_int tbl[16], int idx)
-{
- int32_t i;
-
- tbl[0] = p256_one;
- for (i = 1; i < 16; ++i)
- conditional_copy(&tbl[i], &tbl[0], ZEROtoONES(i - idx));
-}
-
-/* b = 1/a mod MOD, fixed timing, Fermat's little theorem. */
-void p256_modinv(const p256_int *MOD, const p256_int *a, p256_int *b)
-{
- int i;
- p256_int tbl[16];
-
- /* tbl[i] = a**i, tbl[0] unused. */
- tbl[1] = *a;
- for (i = 2; i < 16; ++i)
- p256_modmul(MOD, &tbl[i-1], 0, a, &tbl[i]);
-
- *b = p256_one;
- for (i = 256; i > 0; i -= 4) {
- int32_t idx = 0;
-
- p256_modmul(MOD, b, 0, b, b);
- p256_modmul(MOD, b, 0, b, b);
- p256_modmul(MOD, b, 0, b, b);
- p256_modmul(MOD, b, 0, b, b);
- idx |= p256_get_bit(&SECP256r1_nMin2, i - 1) << 3;
- idx |= p256_get_bit(&SECP256r1_nMin2, i - 2) << 2;
- idx |= p256_get_bit(&SECP256r1_nMin2, i - 3) << 1;
- idx |= p256_get_bit(&SECP256r1_nMin2, i - 4) << 0;
- set0ToIdx(tbl, idx); /* tbl[0] = tbl[idx] */
- p256_modmul(MOD, b, 0, &tbl[0], &tbl[0]);
- conditional_copy(&tbl[0], b, ~ZEROtoONES(idx));
- }
-}
-
-static int p256_is_even(const p256_int *a)
-{
- return !(P256_DIGIT(a, 0) & 1);
-}
-
-static void p256_shr1(const p256_int *a, int highbit, p256_int *b)
-{
- int i;
-
- for (i = 0; i < P256_NDIGITS - 1; ++i) {
- p256_digit accu = (P256_DIGIT(a, i) >> 1);
-
- accu |= (P256_DIGIT(a, i + 1) << (P256_BITSPERDIGIT - 1));
- P256_DIGIT(b, i) = accu;
- }
- P256_DIGIT(b, i) = (P256_DIGIT(a, i) >> 1) |
- (highbit << (P256_BITSPERDIGIT - 1));
-}
-
-/* b = 1/a mod MOD, binary euclid. */
-void p256_modinv_vartime(const p256_int *MOD, const p256_int *a, p256_int *b)
-{
- p256_int R = P256_ZERO;
- p256_int S = P256_ONE;
- p256_int U = *MOD;
- p256_int V = *a;
-
- for (;;) {
- if (p256_is_even(&U)) {
- p256_shr1(&U, 0, &U);
- if (p256_is_even(&R)) {
- p256_shr1(&R, 0, &R);
- } else {
- /* R = (R + MOD)/2 */
- p256_shr1(&R, p256_add(&R, MOD, &R), &R);
- }
- } else if (p256_is_even(&V)) {
- p256_shr1(&V, 0, &V);
- if (p256_is_even(&S)) {
- p256_shr1(&S, 0, &S);
- } else {
- /* S = (S + MOD)/2 */
- p256_shr1(&S, p256_add(&S, MOD, &S) , &S);
- }
- } else { /* U, V both odd. */
- if (!p256_sub(&V, &U, NULL)) {
- p256_sub(&V, &U, &V);
- if (p256_sub(&S, &R, &S))
- p256_add(&S, MOD, &S);
- if (p256_is_zero(&V))
- break; /* done. */
- } else {
- p256_sub(&U, &V, &U);
- if (p256_sub(&R, &S, &R))
- p256_add(&R, MOD, &R);
- }
- }
- }
-
- p256_mod(MOD, &R, b);
-}
-
-int DCRYPTO_p256_valid_point(const p256_int *x, const p256_int *y)
-{
- p256_int y2, x3;
-
- if (p256_cmp(&SECP256r1_p, x) <= 0 || p256_cmp(&SECP256r1_p, y) <= 0 ||
- p256_is_zero(x) || p256_is_zero(y))
- return 0;
-
- p256_modmul(&SECP256r1_p, y, 0, y, &y2); /* y^2 */
-
- p256_modmul(&SECP256r1_p, x, 0, x, &x3); /* x^2 */
- p256_modmul(&SECP256r1_p, x, 0, &x3, &x3); /* x^3 */
- if (p256_sub(&x3, x, &x3))
- p256_add(&x3, &SECP256r1_p, &x3); /* x^3 - x */
- if (p256_sub(&x3, x, &x3))
- p256_add(&x3, &SECP256r1_p, &x3); /* x^3 - 2x */
- if (p256_sub(&x3, x, &x3))
- p256_add(&x3, &SECP256r1_p, &x3); /* x^3 - 3x */
- if (p256_add(&x3, &SECP256r1_b, &x3)) /* x^3 - 3x + b */
- p256_sub(&x3, &SECP256r1_p, &x3);
- if (p256_sub(&x3, &SECP256r1_p, &x3)) /* make sure 0 <= x3 < p */
- p256_add(&x3, &SECP256r1_p, &x3);
-
- return p256_cmp(&y2, &x3) == 0;
-}
-
/*
* Key selection based on FIPS-186-4, section B.4.2 (Key Pair
* Generation by Testing Candidates).
@@ -447,15 +16,13 @@ int DCRYPTO_p256_valid_point(const p256_int *x, const p256_int *y)
int DCRYPTO_p256_key_from_bytes(p256_int *x, p256_int *y, p256_int *d,
const uint8_t key_bytes[P256_NBYTES])
{
- int valid;
p256_int key;
p256_from_bin(key_bytes, &key);
if (p256_cmp(&SECP256r1_nMin2, &key) < 0)
return 0;
- p256_add(&key, &p256_one, &key);
- valid = DCRYPTO_p256_base_point_mul(x, y, &key);
- if (valid)
- *d = key;
- return valid;
+ p256_add(&key, &p256_one, d);
+ p256_base_point_mul(d, x, y);
+ dcrypto_memset(&key, 0, sizeof(key));
+ return 1;
}
diff --git a/chip/g/dcrypto/p256_ec.c b/chip/g/dcrypto/p256_ec.c
index 12423fb50a..b298493037 100644
--- a/chip/g/dcrypto/p256_ec.c
+++ b/chip/g/dcrypto/p256_ec.c
@@ -3,1359 +3,27 @@
* found in the LICENSE file.
*/
-#include <stdint.h>
-
#include "dcrypto.h"
-typedef uint8_t u8;
-typedef uint32_t u32;
-typedef int32_t s32;
-typedef uint64_t u64;
-
-/* Our field elements are represented as nine 32-bit limbs.
- *
- * The value of an felem (field element) is:
- * x[0] + (x[1] * 2**29) + (x[2] * 2**57) + ... + (x[8] * 2**228)
- *
- * That is, each limb is alternately 29 or 28-bits wide in little-endian
- * order.
- *
- * This means that an felem hits 2**257, rather than 2**256 as we would like. A
- * 28, 29, ... pattern would cause us to hit 2**256, but that causes problems
- * when multiplying as terms end up one bit short of a limb which would require
- * much bit-shifting to correct.
- *
- * Finally, the values stored in an felem are in Montgomery form. So the value
- * |y| is stored as (y*R) mod p, where p is the P-256 prime and R is 2**257.
- */
-typedef u32 limb;
-#define NLIMBS 9
-typedef limb felem[NLIMBS];
-
-static const limb kBottom28Bits = 0xfffffff;
-static const limb kBottom29Bits = 0x1fffffff;
-
-/* kOne is the number 1 as an felem. It's 2**257 mod p split up into 29 and
- * 28-bit words. */
-static const felem kOne = {
- 2, 0, 0, 0xffff800,
- 0x1fffffff, 0xfffffff, 0x1fbfffff, 0x1ffffff,
- 0
-};
-static const felem kZero = {0};
-static const felem kP = {
- 0x1fffffff, 0xfffffff, 0x1fffffff, 0x3ff,
- 0, 0, 0x200000, 0xf000000,
- 0xfffffff
-};
-static const felem k2P = {
- 0x1ffffffe, 0xfffffff, 0x1fffffff, 0x7ff,
- 0, 0, 0x400000, 0xe000000,
- 0x1fffffff
-};
-/* kPrecomputed contains precomputed values to aid the calculation of scalar
- * multiples of the base point, G. It's actually two, equal length, tables
- * concatenated.
- *
- * The first table contains (x,y) felem pairs for 16 multiples of the base
- * point, G.
- *
- * Index | Index (binary) | Value
- * 0 | 0000 | 0G (all zeros, omitted)
- * 1 | 0001 | G
- * 2 | 0010 | 2**64G
- * 3 | 0011 | 2**64G + G
- * 4 | 0100 | 2**128G
- * 5 | 0101 | 2**128G + G
- * 6 | 0110 | 2**128G + 2**64G
- * 7 | 0111 | 2**128G + 2**64G + G
- * 8 | 1000 | 2**192G
- * 9 | 1001 | 2**192G + G
- * 10 | 1010 | 2**192G + 2**64G
- * 11 | 1011 | 2**192G + 2**64G + G
- * 12 | 1100 | 2**192G + 2**128G
- * 13 | 1101 | 2**192G + 2**128G + G
- * 14 | 1110 | 2**192G + 2**128G + 2**64G
- * 15 | 1111 | 2**192G + 2**128G + 2**64G + G
- *
- * The second table follows the same style, but the terms are 2**32G,
- * 2**96G, 2**160G, 2**224G.
- *
- * This is ~2KB of data. */
-static const limb kPrecomputed[NLIMBS * 2 * 15 * 2] = {
- 0x11522878, 0xe730d41, 0xdb60179, 0x4afe2ff, 0x12883add, 0xcaddd88,
- 0x119e7edc, 0xd4a6eab, 0x3120bee, 0x1d2aac15, 0xf25357c, 0x19e45cdd,
- 0x5c721d0, 0x1992c5a5, 0xa237487, 0x154ba21, 0x14b10bb, 0xae3fe3,
- 0xd41a576, 0x922fc51, 0x234994f, 0x60b60d3, 0x164586ae, 0xce95f18,
- 0x1fe49073, 0x3fa36cc, 0x5ebcd2c, 0xb402f2f, 0x15c70bf, 0x1561925c,
- 0x5a26704, 0xda91e90, 0xcdc1c7f, 0x1ea12446, 0xe1ade1e, 0xec91f22,
- 0x26f7778, 0x566847e, 0xa0bec9e, 0x234f453, 0x1a31f21a, 0xd85e75c,
- 0x56c7109, 0xa267a00, 0xb57c050, 0x98fb57, 0xaa837cc, 0x60c0792,
- 0xcfa5e19, 0x61bab9e, 0x589e39b, 0xa324c5, 0x7d6dee7, 0x2976e4b,
- 0x1fc4124a, 0xa8c244b, 0x1ce86762, 0xcd61c7e, 0x1831c8e0, 0x75774e1,
- 0x1d96a5a9, 0x843a649, 0xc3ab0fa, 0x6e2e7d5, 0x7673a2a, 0x178b65e8,
- 0x4003e9b, 0x1a1f11c2, 0x7816ea, 0xf643e11, 0x58c43df, 0xf423fc2,
- 0x19633ffa, 0x891f2b2, 0x123c231c, 0x46add8c, 0x54700dd, 0x59e2b17,
- 0x172db40f, 0x83e277d, 0xb0dd609, 0xfd1da12, 0x35c6e52, 0x19ede20c,
- 0xd19e0c0, 0x97d0f40, 0xb015b19, 0x449e3f5, 0xe10c9e, 0x33ab581,
- 0x56a67ab, 0x577734d, 0x1dddc062, 0xc57b10d, 0x149b39d, 0x26a9e7b,
- 0xc35df9f, 0x48764cd, 0x76dbcca, 0xca4b366, 0xe9303ab, 0x1a7480e7,
- 0x57e9e81, 0x1e13eb50, 0xf466cf3, 0x6f16b20, 0x4ba3173, 0xc168c33,
- 0x15cb5439, 0x6a38e11, 0x73658bd, 0xb29564f, 0x3f6dc5b, 0x53b97e,
- 0x1322c4c0, 0x65dd7ff, 0x3a1e4f6, 0x14e614aa, 0x9246317, 0x1bc83aca,
- 0xad97eed, 0xd38ce4a, 0xf82b006, 0x341f077, 0xa6add89, 0x4894acd,
- 0x9f162d5, 0xf8410ef, 0x1b266a56, 0xd7f223, 0x3e0cb92, 0xe39b672,
- 0x6a2901a, 0x69a8556, 0x7e7c0, 0x9b7d8d3, 0x309a80, 0x1ad05f7f,
- 0xc2fb5dd, 0xcbfd41d, 0x9ceb638, 0x1051825c, 0xda0cf5b, 0x812e881,
- 0x6f35669, 0x6a56f2c, 0x1df8d184, 0x345820, 0x1477d477, 0x1645db1,
- 0xbe80c51, 0xc22be3e, 0xe35e65a, 0x1aeb7aa0, 0xc375315, 0xf67bc99,
- 0x7fdd7b9, 0x191fc1be, 0x61235d, 0x2c184e9, 0x1c5a839, 0x47a1e26,
- 0xb7cb456, 0x93e225d, 0x14f3c6ed, 0xccc1ac9, 0x17fe37f3, 0x4988989,
- 0x1a90c502, 0x2f32042, 0xa17769b, 0xafd8c7c, 0x8191c6e, 0x1dcdb237,
- 0x16200c0, 0x107b32a1, 0x66c08db, 0x10d06a02, 0x3fc93, 0x5620023,
- 0x16722b27, 0x68b5c59, 0x270fcfc, 0xfad0ecc, 0xe5de1c2, 0xeab466b,
- 0x2fc513c, 0x407f75c, 0xbaab133, 0x9705fe9, 0xb88b8e7, 0x734c993,
- 0x1e1ff8f, 0x19156970, 0xabd0f00, 0x10469ea7, 0x3293ac0, 0xcdc98aa,
- 0x1d843fd, 0xe14bfe8, 0x15be825f, 0x8b5212, 0xeb3fb67, 0x81cbd29,
- 0xbc62f16, 0x2b6fcc7, 0xf5a4e29, 0x13560b66, 0xc0b6ac2, 0x51ae690,
- 0xd41e271, 0xf3e9bd4, 0x1d70aab, 0x1029f72, 0x73e1c35, 0xee70fbc,
- 0xad81baf, 0x9ecc49a, 0x86c741e, 0xfe6be30, 0x176752e7, 0x23d416,
- 0x1f83de85, 0x27de188, 0x66f70b8, 0x181cd51f, 0x96b6e4c, 0x188f2335,
- 0xa5df759, 0x17a77eb6, 0xfeb0e73, 0x154ae914, 0x2f3ec51, 0x3826b59,
- 0xb91f17d, 0x1c72949, 0x1362bf0a, 0xe23fddf, 0xa5614b0, 0xf7d8f,
- 0x79061, 0x823d9d2, 0x8213f39, 0x1128ae0b, 0xd095d05, 0xb85c0c2,
- 0x1ecb2ef, 0x24ddc84, 0xe35e901, 0x18411a4a, 0xf5ddc3d, 0x3786689,
- 0x52260e8, 0x5ae3564, 0x542b10d, 0x8d93a45, 0x19952aa4, 0x996cc41,
- 0x1051a729, 0x4be3499, 0x52b23aa, 0x109f307e, 0x6f5b6bb, 0x1f84e1e7,
- 0x77a0cfa, 0x10c4df3f, 0x25a02ea, 0xb048035, 0xe31de66, 0xc6ecaa3,
- 0x28ea335, 0x2886024, 0x1372f020, 0xf55d35, 0x15e4684c, 0xf2a9e17,
- 0x1a4a7529, 0xcb7beb1, 0xb2a78a1, 0x1ab21f1f, 0x6361ccf, 0x6c9179d,
- 0xb135627, 0x1267b974, 0x4408bad, 0x1cbff658, 0xe3d6511, 0xc7d76f,
- 0x1cc7a69, 0xe7ee31b, 0x54fab4f, 0x2b914f, 0x1ad27a30, 0xcd3579e,
- 0xc50124c, 0x50daa90, 0xb13f72, 0xb06aa75, 0x70f5cc6, 0x1649e5aa,
- 0x84a5312, 0x329043c, 0x41c4011, 0x13d32411, 0xb04a838, 0xd760d2d,
- 0x1713b532, 0xbaa0c03, 0x84022ab, 0x6bcf5c1, 0x2f45379, 0x18ae070,
- 0x18c9e11e, 0x20bca9a, 0x66f496b, 0x3eef294, 0x67500d2, 0xd7f613c,
- 0x2dbbeb, 0xb741038, 0xe04133f, 0x1582968d, 0xbe985f7, 0x1acbc1a,
- 0x1a6a939f, 0x33e50f6, 0xd665ed4, 0xb4b7bd6, 0x1e5a3799, 0x6b33847,
- 0x17fa56ff, 0x65ef930, 0x21dc4a, 0x2b37659, 0x450fe17, 0xb357b65,
- 0xdf5efac, 0x15397bef, 0x9d35a7f, 0x112ac15f, 0x624e62e, 0xa90ae2f,
- 0x107eecd2, 0x1f69bbe, 0x77d6bce, 0x5741394, 0x13c684fc, 0x950c910,
- 0x725522b, 0xdc78583, 0x40eeabb, 0x1fde328a, 0xbd61d96, 0xd28c387,
- 0x9e77d89, 0x12550c40, 0x759cb7d, 0x367ef34, 0xae2a960, 0x91b8bdc,
- 0x93462a9, 0xf469ef, 0xb2e9aef, 0xd2ca771, 0x54e1f42, 0x7aaa49,
- 0x6316abb, 0x2413c8e, 0x5425bf9, 0x1bed3e3a, 0xf272274, 0x1f5e7326,
- 0x6416517, 0xea27072, 0x9cedea7, 0x6e7633, 0x7c91952, 0xd806dce,
- 0x8e2a7e1, 0xe421e1a, 0x418c9e1, 0x1dbc890, 0x1b395c36, 0xa1dc175,
- 0x1dc4ef73, 0x8956f34, 0xe4b5cf2, 0x1b0d3a18, 0x3194a36, 0x6c2641f,
- 0xe44124c, 0xa2f4eaa, 0xa8c25ba, 0xf927ed7, 0x627b614, 0x7371cca,
- 0xba16694, 0x417bc03, 0x7c0a7e3, 0x9c35c19, 0x1168a205, 0x8b6b00d,
- 0x10e3edc9, 0x9c19bf2, 0x5882229, 0x1b2b4162, 0xa5cef1a, 0x1543622b,
- 0x9bd433e, 0x364e04d, 0x7480792, 0x5c9b5b3, 0xe85ff25, 0x408ef57,
- 0x1814cfa4, 0x121b41b, 0xd248a0f, 0x3b05222, 0x39bb16a, 0xc75966d,
- 0xa038113, 0xa4a1769, 0x11fbc6c, 0x917e50e, 0xeec3da8, 0x169d6eac,
- 0x10c1699, 0xa416153, 0xf724912, 0x15cd60b7, 0x4acbad9, 0x5efc5fa,
- 0xf150ed7, 0x122b51, 0x1104b40a, 0xcb7f442, 0xfbb28ff, 0x6ac53ca,
- 0x196142cc, 0x7bf0fa9, 0x957651, 0x4e0f215, 0xed439f8, 0x3f46bd5,
- 0x5ace82f, 0x110916b6, 0x6db078, 0xffd7d57, 0xf2ecaac, 0xca86dec,
- 0x15d6b2da, 0x965ecc9, 0x1c92b4c2, 0x1f3811, 0x1cb080f5, 0x2d8b804,
- 0x19d1c12d, 0xf20bd46, 0x1951fa7, 0xa3656c3, 0x523a425, 0xfcd0692,
- 0xd44ddc8, 0x131f0f5b, 0xaf80e4a, 0xcd9fc74, 0x99bb618, 0x2db944c,
- 0xa673090, 0x1c210e1, 0x178c8d23, 0x1474383, 0x10b8743d, 0x985a55b,
- 0x2e74779, 0x576138, 0x9587927, 0x133130fa, 0xbe05516, 0x9f4d619,
- 0xbb62570, 0x99ec591, 0xd9468fe, 0x1d07782d, 0xfc72e0b, 0x701b298,
- 0x1863863b, 0x85954b8, 0x121a0c36, 0x9e7fedf, 0xf64b429, 0x9b9d71e,
- 0x14e2f5d8, 0xf858d3a, 0x942eea8, 0xda5b765, 0x6edafff, 0xa9d18cc,
- 0xc65e4ba, 0x1c747e86, 0xe4ea915, 0x1981d7a1, 0x8395659, 0x52ed4e2,
- 0x87d43b7, 0x37ab11b, 0x19d292ce, 0xf8d4692, 0x18c3053f, 0x8863e13,
- 0x4c146c0, 0x6bdf55a, 0x4e4457d, 0x16152289, 0xac78ec2, 0x1a59c5a2,
- 0x2028b97, 0x71c2d01, 0x295851f, 0x404747b, 0x878558d, 0x7d29aa4,
- 0x13d8341f, 0x8daefd7, 0x139c972d, 0x6b7ea75, 0xd4a9dde, 0xff163d8,
- 0x81d55d7, 0xa5bef68, 0xb7b30d8, 0xbe73d6f, 0xaa88141, 0xd976c81,
- 0x7e7a9cc, 0x18beb771, 0xd773cbd, 0x13f51951, 0x9d0c177, 0x1c49a78,
-};
-
-
-/* Field element operations: */
-
-/* NON_ZERO_TO_ALL_ONES returns:
- * 0xffffffff for 0 < x <= 2**31
- * 0 for x == 0 or x > 2**31.
- *
- * x must be a u32 or an equivalent type such as limb. */
-#define NON_ZERO_TO_ALL_ONES(x) ((((u32)(x) - 1) >> 31) - 1)
-
-/* felem_reduce_carry adds a multiple of p in order to cancel |carry|,
- * which is a term at 2**257.
- *
- * On entry: carry < 2**3, inout[0,2,...] < 2**29, inout[1,3,...] < 2**28.
- * On exit: inout[0,2,..] < 2**30, inout[1,3,...] < 2**29. */
-static void felem_reduce_carry(felem inout, limb carry)
-{
- const u32 carry_mask = NON_ZERO_TO_ALL_ONES(carry);
-
- inout[0] += carry << 1;
- inout[3] += 0x10000000 & carry_mask;
- /* carry < 2**3 thus (carry << 11) < 2**14 and we added 2**28 in the
- * previous line therefore this doesn't underflow. */
- inout[3] -= carry << 11;
- inout[4] += (0x20000000 - 1) & carry_mask;
- inout[5] += (0x10000000 - 1) & carry_mask;
- inout[6] += (0x20000000 - 1) & carry_mask;
- inout[6] -= carry << 22;
- /* This may underflow if carry is non-zero but, if so, we'll
- * fix it in the next line. */
- inout[7] -= 1 & carry_mask;
- inout[7] += carry << 25;
-}
-
-/* felem_sum sets out = in+in2.
- *
- * On entry, in[i]+in2[i] must not overflow a 32-bit word.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29 */
-static void felem_sum(felem out, const felem in, const felem in2)
-{
- limb carry = 0;
- unsigned i;
-
- for (i = 0;; i++) {
- out[i] = in[i] + in2[i];
- out[i] += carry;
- carry = out[i] >> 29;
- out[i] &= kBottom29Bits;
-
- i++;
- if (i == NLIMBS)
- break;
-
- out[i] = in[i] + in2[i];
- out[i] += carry;
- carry = out[i] >> 28;
- out[i] &= kBottom28Bits;
- }
-
- felem_reduce_carry(out, carry);
-}
-
-#define two31m3 ((((limb)1) << 31) - (((limb)1) << 3))
-#define two30m2 ((((limb)1) << 30) - (((limb)1) << 2))
-#define two30p13m2 ((((limb)1) << 30) + (((limb)1) << 13) - (((limb)1) << 2))
-#define two31m2 ((((limb)1) << 31) - (((limb)1) << 2))
-#define two31p24m2 ((((limb)1) << 31) + (((limb)1) << 24) - (((limb)1) << 2))
-#define two30m27m2 ((((limb)1) << 30) - (((limb)1) << 27) - (((limb)1) << 2))
-
-/* zero31 is 0 mod p. */
-static const felem zero31 = { two31m3, two30m2, two31m2, two30p13m2, two31m2,
- two30m2, two31p24m2, two30m27m2, two31m2 };
-
-/* felem_diff sets out = in-in2.
- *
- * On entry: in[0,2,...] < 2**30, in[1,3,...] < 2**29 and
- * in2[0,2,...] < 2**30, in2[1,3,...] < 2**29.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29. */
-static void felem_diff(felem out, const felem in, const felem in2)
-{
- limb carry = 0;
- unsigned i;
-
- for (i = 0;; i++) {
- out[i] = in[i] - in2[i];
- out[i] += zero31[i];
- out[i] += carry;
- carry = out[i] >> 29;
- out[i] &= kBottom29Bits;
-
- i++;
- if (i == NLIMBS)
- break;
-
- out[i] = in[i] - in2[i];
- out[i] += zero31[i];
- out[i] += carry;
- carry = out[i] >> 28;
- out[i] &= kBottom28Bits;
- }
-
- felem_reduce_carry(out, carry);
-}
-
-/* felem_reduce_degree sets out = tmp/R mod p where tmp contains 64-bit words
- * with the same 29,28,... bit positions as an felem.
- *
- * The values in felems are in Montgomery form: x*R mod p where R = 2**257.
- * Since we just multiplied two Montgomery values together, the result is
- * x*y*R*R mod p. We wish to divide by R in order for the result also to be
- * in Montgomery form.
- *
- * On entry: tmp[i] < 2**64
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29 */
-static void felem_reduce_degree(felem out, u64 tmp[17])
-{
- /* The following table may be helpful when reading this code:
- *
- * Limb number: 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10...
- * Width (bits): 29| 28| 29| 28| 29| 28| 29| 28| 29| 28| 29
- * Start bit: 0 | 29| 57| 86|114|143|171|200|228|257|285
- * (odd phase): 0 | 28| 57| 85|114|142|171|199|228|256|285 */
- limb tmp2[18], carry, x, xMask;
- unsigned i;
-
- /* tmp contains 64-bit words with the same 29,28,29-bit positions as an
- * felem. So the top of an element of tmp might overlap with another
- * element two positions down. The following loop eliminates this
- * overlap. */
- tmp2[0] = (limb)(tmp[0] & kBottom29Bits);
-
- /* In the following we use "(limb) tmp[x]" and "(limb)
- * (tmp[x]>>32)" to try and hint to the compiler that it can
- * do a single-word shift by selecting the right register
- * rather than doing a double-word shift and truncating
- * afterwards. */
- tmp2[1] = ((limb) tmp[0]) >> 29;
- tmp2[1] |= (((limb)(tmp[0] >> 32)) << 3) & kBottom28Bits;
- tmp2[1] += ((limb) tmp[1]) & kBottom28Bits;
- carry = tmp2[1] >> 28;
- tmp2[1] &= kBottom28Bits;
-
- for (i = 2; i < 17; i++) {
- tmp2[i] = ((limb)(tmp[i - 2] >> 32)) >> 25;
- tmp2[i] += ((limb)(tmp[i - 1])) >> 28;
- tmp2[i] += (((limb)(tmp[i - 1] >> 32)) << 4) & kBottom29Bits;
- tmp2[i] += ((limb) tmp[i]) & kBottom29Bits;
- tmp2[i] += carry;
- carry = tmp2[i] >> 29;
- tmp2[i] &= kBottom29Bits;
-
- i++;
- if (i == 17)
- break;
- tmp2[i] = ((limb)(tmp[i - 2] >> 32)) >> 25;
- tmp2[i] += ((limb)(tmp[i - 1])) >> 29;
- tmp2[i] += (((limb)(tmp[i - 1] >> 32)) << 3) & kBottom28Bits;
- tmp2[i] += ((limb) tmp[i]) & kBottom28Bits;
- tmp2[i] += carry;
- carry = tmp2[i] >> 28;
- tmp2[i] &= kBottom28Bits;
- }
-
- tmp2[17] = ((limb)(tmp[15] >> 32)) >> 25;
- tmp2[17] += ((limb)(tmp[16])) >> 29;
- tmp2[17] += (((limb)(tmp[16] >> 32)) << 3);
- tmp2[17] += carry;
-
- /* Montgomery elimination of terms.
- *
- * Since R is 2**257, we can divide by R with a bitwise shift
- * if we can ensure that the right-most 257 bits are all
- * zero. We can make that true by adding multiplies of p
- * without affecting the value.
- *
- * So we eliminate limbs from right to left. Since the bottom
- * 29 bits of p are all ones, then by adding tmp2[0]*p to tmp2
- * we'll make tmp2[0] == 0. We can do that for 8 further
- * limbs and then right shift to eliminate the extra factor of
- * R. */
- for (i = 0;; i += 2) {
- tmp2[i + 1] += tmp2[i] >> 29;
- x = tmp2[i] & kBottom29Bits;
- xMask = NON_ZERO_TO_ALL_ONES(x);
- tmp2[i] = 0;
-
- /* The bounds calculations for this loop are
- * tricky. Each iteration of the loop eliminates two
- * words by adding values to words to their right.
- *
- * The following table contains the amounts added to
- * each word (as an offset from the value of i at the
- * top of the loop). The amounts are accounted for
- * from the first and second half of the loop
- * separately and are written as, for example, 28 to
- * mean a value < 2**28.
- *
- * Word: 3 4 5 6 7 8 9 10
- * Added in top half: 28 11 29 21 29 28
- * 28 29
- * 29
- * Added in bottom half: 29 10 28 21 28 28
- * 29
- *
- * The value that is currently offset 7 will be offset
- * 5 for the next iteration and then offset 3 for the
- * iteration after that. Therefore the total value
- * added will be the values added at 7, 5 and 3.
- *
- * The following table accumulates these values. The
- * sums at the bottom are written as, for example,
- * 29+28, to mean a value < 2**29+2**28.
- *
- * Word: 3 4 5 6 7 8 9 10 11 12 13
- * 28 11 10 29 21 29 28 28 28 28 28
- * 29 28 11 28 29 28 29 28 29 28
- * 29 28 21 21 29 21 29 21
- * 10 29 28 21 28 21 28
- * 28 29 28 29 28 29 28
- * 11 10 29 10 29 10
- * 29 28 11 28 11
- * 29 29
- * --------------------------------------------
- * 30+ 31+ 30+ 31+ 30+
- * 28+ 29+ 28+ 29+ 21+
- * 21+ 28+ 21+ 28+ 10
- * 10 21+ 10 21+
- * 11 11
- *
- * So the greatest amount is added to tmp2[10] and
- * tmp2[12]. If tmp2[10/12] has an initial value of
- * <2**29, then the maximum value will be < 2**31 +
- * 2**30 + 2**28 + 2**21 + 2**11, which is < 2**32, as
- * required. */
- tmp2[i + 3] += (x << 10) & kBottom28Bits;
- tmp2[i + 4] += (x >> 18);
-
- tmp2[i + 6] += (x << 21) & kBottom29Bits;
- tmp2[i + 7] += x >> 8;
-
- /* At position 200, which is the starting bit position
- * for word 7, we have a factor of 0xf000000 = 2**28 -
- * 2**24. */
- tmp2[i + 7] += 0x10000000 & xMask;
- /* Word 7 is 28 bits wide, so the 2**28 term exactly
- * hits word 8. */
- tmp2[i + 8] += (x - 1) & xMask;
- tmp2[i + 7] -= (x << 24) & kBottom28Bits;
- tmp2[i + 8] -= x >> 4;
-
- tmp2[i + 8] += 0x20000000 & xMask;
- tmp2[i + 8] -= x;
- tmp2[i + 8] += (x << 28) & kBottom29Bits;
- tmp2[i + 9] += ((x >> 1) - 1) & xMask;
-
- if (i+1 == NLIMBS)
- break;
- tmp2[i + 2] += tmp2[i + 1] >> 28;
- x = tmp2[i + 1] & kBottom28Bits;
- xMask = NON_ZERO_TO_ALL_ONES(x);
- tmp2[i + 1] = 0;
-
- tmp2[i + 4] += (x << 11) & kBottom29Bits;
- tmp2[i + 5] += (x >> 18);
-
- tmp2[i + 7] += (x << 21) & kBottom28Bits;
- tmp2[i + 8] += x >> 7;
-
- /* At position 199, which is the starting bit of the
- * 8th word when dealing with a context starting on an
- * odd word, we have a factor of 0x1e000000 = 2**29 -
- * 2**25. Since we have not updated i, the 8th word
- * from i+1 is i+8. */
- tmp2[i + 8] += 0x20000000 & xMask;
- tmp2[i + 9] += (x - 1) & xMask;
- tmp2[i + 8] -= (x << 25) & kBottom29Bits;
- tmp2[i + 9] -= x >> 4;
-
- tmp2[i + 9] += 0x10000000 & xMask;
- tmp2[i + 9] -= x;
- tmp2[i + 10] += (x - 1) & xMask;
- }
-
- /* We merge the right shift with a carry chain. The words
- * above 2**257 have widths of 28,29,... which we need to
- * correct when copying them down. */
- carry = 0;
- for (i = 0; i < 8; i++) {
- /* The maximum value of tmp2[i + 9] occurs on the
- * first iteration and is < 2**30+2**29+2**28. Adding
- * 2**29 (from tmp2[i + 10]) is therefore safe. */
- out[i] = tmp2[i + 9];
- out[i] += carry;
- out[i] += (tmp2[i + 10] << 28) & kBottom29Bits;
- carry = out[i] >> 29;
- out[i] &= kBottom29Bits;
-
- i++;
- out[i] = tmp2[i + 9] >> 1;
- out[i] += carry;
- carry = out[i] >> 28;
- out[i] &= kBottom28Bits;
- }
-
- out[8] = tmp2[17];
- out[8] += carry;
- carry = out[8] >> 29;
- out[8] &= kBottom29Bits;
-
- felem_reduce_carry(out, carry);
-}
-
-/* felem_square sets out=in*in.
- *
- * On entry: in[0,2,...] < 2**30, in[1,3,...] < 2**29.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29. */
-static void felem_square(felem out, const felem in)
-{
- u64 tmp[17];
-
- tmp[0] = ((u64) in[0]) * in[0];
- tmp[1] = ((u64) in[0]) * (in[1] << 1);
- tmp[2] = ((u64) in[0]) * (in[2] << 1) +
- ((u64) in[1]) * (in[1] << 1);
- tmp[3] = ((u64) in[0]) * (in[3] << 1) +
- ((u64) in[1]) * (in[2] << 1);
- tmp[4] = ((u64) in[0]) * (in[4] << 1) +
- ((u64) in[1]) * (in[3] << 2) + ((u64) in[2]) * in[2];
- tmp[5] = ((u64) in[0]) * (in[5] << 1) + ((u64) in[1]) *
- (in[4] << 1) + ((u64) in[2]) * (in[3] << 1);
- tmp[6] = ((u64) in[0]) * (in[6] << 1) + ((u64) in[1]) *
- (in[5] << 2) + ((u64) in[2]) * (in[4] << 1) +
- ((u64) in[3]) * (in[3] << 1);
- tmp[7] = ((u64) in[0]) * (in[7] << 1) + ((u64) in[1]) *
- (in[6] << 1) + ((u64) in[2]) * (in[5] << 1) +
- ((u64) in[3]) * (in[4] << 1);
- /* tmp[8] has the greatest value of 2**61 + 2**60 + 2**61 +
- * 2**60 + 2**60, which is < 2**64 as required. */
- tmp[8] = ((u64) in[0]) * (in[8] << 1) + ((u64) in[1]) *
- (in[7] << 2) + ((u64) in[2]) * (in[6] << 1) +
- ((u64) in[3]) * (in[5] << 2) + ((u64) in[4]) * in[4];
- tmp[9] = ((u64) in[1]) * (in[8] << 1) + ((u64) in[2]) *
- (in[7] << 1) + ((u64) in[3]) * (in[6] << 1) +
- ((u64) in[4]) * (in[5] << 1);
- tmp[10] = ((u64) in[2]) * (in[8] << 1) + ((u64) in[3]) *
- (in[7] << 2) + ((u64) in[4]) * (in[6] << 1) +
- ((u64) in[5]) * (in[5] << 1);
- tmp[11] = ((u64) in[3]) * (in[8] << 1) + ((u64) in[4]) *
- (in[7] << 1) + ((u64) in[5]) * (in[6] << 1);
- tmp[12] = ((u64) in[4]) * (in[8] << 1) +
- ((u64) in[5]) * (in[7] << 2) + ((u64) in[6]) * in[6];
- tmp[13] = ((u64) in[5]) * (in[8] << 1) +
- ((u64) in[6]) * (in[7] << 1);
- tmp[14] = ((u64) in[6]) * (in[8] << 1) +
- ((u64) in[7]) * (in[7] << 1);
- tmp[15] = ((u64) in[7]) * (in[8] << 1);
- tmp[16] = ((u64) in[8]) * in[8];
-
- felem_reduce_degree(out, tmp);
-}
-
-/* felem_mul sets out=in*in2.
- *
- * On entry: in[0,2,...] < 2**30, in[1,3,...] < 2**29 and
- * in2[0,2,...] < 2**30, in2[1,3,...] < 2**29.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29. */
-static void felem_mul(felem out, const felem in, const felem in2)
-{
- u64 tmp[17];
-
- tmp[0] = ((u64) in[0]) * in2[0];
- tmp[1] = ((u64) in[0]) * (in2[1] << 0) +
- ((u64) in[1]) * (in2[0] << 0);
- tmp[2] = ((u64) in[0]) * (in2[2] << 0) + ((u64) in[1]) *
- (in2[1] << 1) + ((u64) in[2]) * (in2[0] << 0);
- tmp[3] = ((u64) in[0]) * (in2[3] << 0) + ((u64) in[1]) *
- (in2[2] << 0) + ((u64) in[2]) * (in2[1] << 0) +
- ((u64) in[3]) * (in2[0] << 0);
- tmp[4] = ((u64) in[0]) * (in2[4] << 0) + ((u64) in[1]) *
- (in2[3] << 1) + ((u64) in[2]) * (in2[2] << 0) +
- ((u64) in[3]) * (in2[1] << 1) +
- ((u64) in[4]) * (in2[0] << 0);
- tmp[5] = ((u64) in[0]) * (in2[5] << 0) + ((u64) in[1]) *
- (in2[4] << 0) + ((u64) in[2]) * (in2[3] << 0) +
- ((u64) in[3]) * (in2[2] << 0) + ((u64) in[4]) *
- (in2[1] << 0) + ((u64) in[5]) * (in2[0] << 0);
- tmp[6] = ((u64) in[0]) * (in2[6] << 0) + ((u64) in[1]) *
- (in2[5] << 1) + ((u64) in[2]) * (in2[4] << 0) +
- ((u64) in[3]) * (in2[3] << 1) + ((u64) in[4]) *
- (in2[2] << 0) + ((u64) in[5]) * (in2[1] << 1) +
- ((u64) in[6]) * (in2[0] << 0);
- tmp[7] = ((u64) in[0]) * (in2[7] << 0) + ((u64) in[1]) *
- (in2[6] << 0) + ((u64) in[2]) * (in2[5] << 0) +
- ((u64) in[3]) * (in2[4] << 0) + ((u64) in[4]) *
- (in2[3] << 0) + ((u64) in[5]) * (in2[2] << 0) +
- ((u64) in[6]) * (in2[1] << 0) +
- ((u64) in[7]) * (in2[0] << 0);
- /* tmp[8] has the greatest value but doesn't overflow. See logic in
- * felem_square. */
- tmp[8] = ((u64) in[0]) * (in2[8] << 0) + ((u64) in[1]) *
- (in2[7] << 1) + ((u64) in[2]) * (in2[6] << 0) +
- ((u64) in[3]) * (in2[5] << 1) + ((u64) in[4]) *
- (in2[4] << 0) + ((u64) in[5]) * (in2[3] << 1) +
- ((u64) in[6]) * (in2[2] << 0) + ((u64) in[7]) *
- (in2[1] << 1) + ((u64) in[8]) * (in2[0] << 0);
- tmp[9] = ((u64) in[1]) * (in2[8] << 0) + ((u64) in[2]) *
- (in2[7] << 0) + ((u64) in[3]) * (in2[6] << 0) +
- ((u64) in[4]) * (in2[5] << 0) + ((u64) in[5]) *
- (in2[4] << 0) + ((u64) in[6]) * (in2[3] << 0) +
- ((u64) in[7]) * (in2[2] << 0) +
- ((u64) in[8]) * (in2[1] << 0);
- tmp[10] = ((u64) in[2]) * (in2[8] << 0) + ((u64) in[3]) *
- (in2[7] << 1) + ((u64) in[4]) * (in2[6] << 0) +
- ((u64) in[5]) * (in2[5] << 1) + ((u64) in[6]) *
- (in2[4] << 0) + ((u64) in[7]) * (in2[3] << 1) +
- ((u64) in[8]) * (in2[2] << 0);
- tmp[11] = ((u64) in[3]) * (in2[8] << 0) + ((u64) in[4]) *
- (in2[7] << 0) + ((u64) in[5]) * (in2[6] << 0) +
- ((u64) in[6]) * (in2[5] << 0) + ((u64) in[7]) *
- (in2[4] << 0) + ((u64) in[8]) * (in2[3] << 0);
- tmp[12] = ((u64) in[4]) * (in2[8] << 0) + ((u64) in[5]) *
- (in2[7] << 1) + ((u64) in[6]) * (in2[6] << 0) +
- ((u64) in[7]) * (in2[5] << 1) +
- ((u64) in[8]) * (in2[4] << 0);
- tmp[13] = ((u64) in[5]) * (in2[8] << 0) + ((u64) in[6]) *
- (in2[7] << 0) + ((u64) in[7]) * (in2[6] << 0) +
- ((u64) in[8]) * (in2[5] << 0);
- tmp[14] = ((u64) in[6]) * (in2[8] << 0) + ((u64) in[7]) *
- (in2[7] << 1) + ((u64) in[8]) * (in2[6] << 0);
- tmp[15] = ((u64) in[7]) * (in2[8] << 0) +
- ((u64) in[8]) * (in2[7] << 0);
- tmp[16] = ((u64) in[8]) * (in2[8] << 0);
-
- felem_reduce_degree(out, tmp);
-}
-
-static void felem_assign(felem out, const felem in)
-{
- memcpy(out, in, sizeof(felem));
-}
-
-/* felem_inv calculates |out| = |in|^{-1}
- *
- * Based on Fermat's Little Theorem:
- * a^p = a (mod p)
- * a^{p-1} = 1 (mod p)
- * a^{p-2} = a^{-1} (mod p)
- */
-static void felem_inv(felem out, const felem in)
-{
- felem ftmp, ftmp2;
- /* each e_I will hold |in|^{2^I - 1} */
- felem e2, e4, e8, e16, e32, e64;
- unsigned i;
-
- felem_square(ftmp, in); /* 2^1 */
- felem_mul(ftmp, in, ftmp); /* 2^2 - 2^0 */
- felem_assign(e2, ftmp);
- felem_square(ftmp, ftmp); /* 2^3 - 2^1 */
- felem_square(ftmp, ftmp); /* 2^4 - 2^2 */
- felem_mul(ftmp, ftmp, e2); /* 2^4 - 2^0 */
- felem_assign(e4, ftmp);
- felem_square(ftmp, ftmp); /* 2^5 - 2^1 */
- felem_square(ftmp, ftmp); /* 2^6 - 2^2 */
- felem_square(ftmp, ftmp); /* 2^7 - 2^3 */
- felem_square(ftmp, ftmp); /* 2^8 - 2^4 */
- felem_mul(ftmp, ftmp, e4); /* 2^8 - 2^0 */
- felem_assign(e8, ftmp);
- for (i = 0; i < 8; i++)
- felem_square(ftmp, ftmp);
- /* 2^16 - 2^8 */
- felem_mul(ftmp, ftmp, e8); /* 2^16 - 2^0 */
- felem_assign(e16, ftmp);
- for (i = 0; i < 16; i++)
- felem_square(ftmp, ftmp);
- /* 2^32 - 2^16 */
- felem_mul(ftmp, ftmp, e16); /* 2^32 - 2^0 */
- felem_assign(e32, ftmp);
- for (i = 0; i < 32; i++)
- felem_square(ftmp, ftmp);
- /* 2^64 - 2^32 */
- felem_assign(e64, ftmp);
- felem_mul(ftmp, ftmp, in); /* 2^64 - 2^32 + 2^0 */
- for (i = 0; i < 192; i++)
- felem_square(ftmp, ftmp);
- /* 2^256 - 2^224 + 2^192 */
-
- felem_mul(ftmp2, e64, e32); /* 2^64 - 2^0 */
- for (i = 0; i < 16; i++)
- felem_square(ftmp2, ftmp2);
- /* 2^80 - 2^16 */
- felem_mul(ftmp2, ftmp2, e16); /* 2^80 - 2^0 */
- for (i = 0; i < 8; i++)
- felem_square(ftmp2, ftmp2);
- /* 2^88 - 2^8 */
- felem_mul(ftmp2, ftmp2, e8); /* 2^88 - 2^0 */
- for (i = 0; i < 4; i++)
- felem_square(ftmp2, ftmp2);
- /* 2^92 - 2^4 */
- felem_mul(ftmp2, ftmp2, e4); /* 2^92 - 2^0 */
- felem_square(ftmp2, ftmp2); /* 2^93 - 2^1 */
- felem_square(ftmp2, ftmp2); /* 2^94 - 2^2 */
- felem_mul(ftmp2, ftmp2, e2); /* 2^94 - 2^0 */
- felem_square(ftmp2, ftmp2); /* 2^95 - 2^1 */
- felem_square(ftmp2, ftmp2); /* 2^96 - 2^2 */
- felem_mul(ftmp2, ftmp2, in); /* 2^96 - 3 */
-
- felem_mul(out, ftmp2, ftmp); /* 2^256 - 2^224 + 2^192 + 2^96 - 3 */
-}
-
-/* felem_scalar_3 sets out=3*out.
- *
- * On entry: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29. */
-static void felem_scalar_3(felem out)
-{
- limb carry = 0;
- unsigned i;
-
- for (i = 0;; i++) {
- out[i] *= 3;
- out[i] += carry;
- carry = out[i] >> 29;
- out[i] &= kBottom29Bits;
-
- i++;
- if (i == NLIMBS)
- break;
-
- out[i] *= 3;
- out[i] += carry;
- carry = out[i] >> 28;
- out[i] &= kBottom28Bits;
- }
-
- felem_reduce_carry(out, carry);
-}
-
-/* felem_scalar_4 sets out=4*out.
- *
- * On entry: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29. */
-static void felem_scalar_4(felem out)
-{
- limb carry = 0, next_carry;
- unsigned i;
-
- for (i = 0;; i++) {
- next_carry = out[i] >> 27;
- out[i] <<= 2;
- out[i] &= kBottom29Bits;
- out[i] += carry;
- carry = next_carry + (out[i] >> 29);
- out[i] &= kBottom29Bits;
-
- i++;
- if (i == NLIMBS)
- break;
-
- next_carry = out[i] >> 26;
- out[i] <<= 2;
- out[i] &= kBottom28Bits;
- out[i] += carry;
- carry = next_carry + (out[i] >> 28);
- out[i] &= kBottom28Bits;
- }
-
- felem_reduce_carry(out, carry);
-}
-
-/* felem_scalar_8 sets out=8*out.
- *
- * On entry: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
- * On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29. */
-static void felem_scalar_8(felem out)
-{
- limb carry = 0, next_carry;
- unsigned i;
-
- for (i = 0;; i++) {
- next_carry = out[i] >> 26;
- out[i] <<= 3;
- out[i] &= kBottom29Bits;
- out[i] += carry;
- carry = next_carry + (out[i] >> 29);
- out[i] &= kBottom29Bits;
-
- i++;
- if (i == NLIMBS)
- break;
-
- next_carry = out[i] >> 25;
- out[i] <<= 3;
- out[i] &= kBottom28Bits;
- out[i] += carry;
- carry = next_carry + (out[i] >> 28);
- out[i] &= kBottom28Bits;
- }
-
- felem_reduce_carry(out, carry);
-}
-
-/* felem_is_zero_vartime returns 1 iff |in| == 0. It takes a variable amount of
- * time depending on the value of |in|. */
-static char felem_is_zero_vartime(const felem in)
-{
- limb carry;
- int i;
- limb tmp[NLIMBS];
-
- felem_assign(tmp, in);
-
- /* First, reduce tmp to a minimal form. */
- do {
- carry = 0;
- for (i = 0;; i++) {
- tmp[i] += carry;
- carry = tmp[i] >> 29;
- tmp[i] &= kBottom29Bits;
-
- i++;
- if (i == NLIMBS)
- break;
-
- tmp[i] += carry;
- carry = tmp[i] >> 28;
- tmp[i] &= kBottom28Bits;
- }
-
- felem_reduce_carry(tmp, carry);
- } while (carry);
-
- /* tmp < 2**257, so the only possible zero values are 0, p and 2p. */
- return memcmp(tmp, kZero, sizeof(tmp)) == 0 ||
- memcmp(tmp, kP, sizeof(tmp)) == 0 ||
- memcmp(tmp, k2P, sizeof(tmp)) == 0;
-}
-
-/* Group operations:
- *
- * Elements of the elliptic curve group are represented in Jacobian
- * coordinates: (x, y, z). An affine point (x', y') is x'=x/z**2, y'=y/z**3 in
- * Jacobian form. */
-
-/* point_double sets {x_out,y_out,z_out} = 2*{x,y,z}.
- *
- * See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#doubling-dbl-2009-l */
-static void point_double(felem x_out, felem y_out, felem z_out, const felem x,
- const felem y, const felem z)
-{
- felem delta, gamma, alpha, beta, tmp, tmp2;
-
- felem_square(delta, z);
- felem_square(gamma, y);
- felem_mul(beta, x, gamma);
-
- felem_sum(tmp, x, delta);
- felem_diff(tmp2, x, delta);
- felem_mul(alpha, tmp, tmp2);
- felem_scalar_3(alpha);
-
- felem_sum(tmp, y, z);
- felem_square(tmp, tmp);
- felem_diff(tmp, tmp, gamma);
- felem_diff(z_out, tmp, delta);
-
- felem_scalar_4(beta);
- felem_square(x_out, alpha);
- felem_diff(x_out, x_out, beta);
- felem_diff(x_out, x_out, beta);
-
- felem_diff(tmp, beta, x_out);
- felem_mul(tmp, alpha, tmp);
- felem_square(tmp2, gamma);
- felem_scalar_8(tmp2);
- felem_diff(y_out, tmp, tmp2);
-}
-
-/* point_add_mixed sets {x_out,y_out,z_out} = {x1,y1,z1} + {x2,y2,1}.
- * (i.e. the second point is affine.)
- *
- * See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#addition-add-2007-bl
- *
- * Note that this function does not handle P+P, infinity+P nor P+infinity
- * correctly. */
-static void point_add_mixed(felem x_out, felem y_out, felem z_out,
- const felem x1, const felem y1, const felem z1,
- const felem x2, const felem y2)
-{
- felem z1z1, z1z1z1, s2, u2, h, i, j, r, rr, v, tmp;
-
- felem_square(z1z1, z1);
- felem_sum(tmp, z1, z1);
-
- felem_mul(u2, x2, z1z1);
- felem_mul(z1z1z1, z1, z1z1);
- felem_mul(s2, y2, z1z1z1);
- felem_diff(h, u2, x1);
- felem_sum(i, h, h);
- felem_square(i, i);
- felem_mul(j, h, i);
- felem_diff(r, s2, y1);
- felem_sum(r, r, r);
- felem_mul(v, x1, i);
-
- felem_mul(z_out, tmp, h);
- felem_square(rr, r);
- felem_diff(x_out, rr, j);
- felem_diff(x_out, x_out, v);
- felem_diff(x_out, x_out, v);
-
- felem_diff(tmp, v, x_out);
- felem_mul(y_out, tmp, r);
- felem_mul(tmp, y1, j);
- felem_diff(y_out, y_out, tmp);
- felem_diff(y_out, y_out, tmp);
-}
-
-/* point_add sets {x_out,y_out,z_out} = {x1,y1,z1} + {x2,y2,z2}.
- *
- * See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#addition-add-2007-bl
- *
- * Note that this function does not handle P+P, infinity+P nor P+infinity
- * correctly. */
-static void point_add(felem x_out, felem y_out, felem z_out, const felem x1,
- const felem y1, const felem z1, const felem x2,
- const felem y2, const felem z2)
-{
- felem z1z1, z1z1z1, z2z2, z2z2z2, s1, s2, u1, u2, h, i, j, r, rr,
- v, tmp;
-
- felem_square(z1z1, z1);
- felem_square(z2z2, z2);
- felem_mul(u1, x1, z2z2);
-
- felem_sum(tmp, z1, z2);
- felem_square(tmp, tmp);
- felem_diff(tmp, tmp, z1z1);
- felem_diff(tmp, tmp, z2z2);
-
- felem_mul(z2z2z2, z2, z2z2);
- felem_mul(s1, y1, z2z2z2);
-
- felem_mul(u2, x2, z1z1);
- felem_mul(z1z1z1, z1, z1z1);
- felem_mul(s2, y2, z1z1z1);
- felem_diff(h, u2, u1);
- felem_sum(i, h, h);
- felem_square(i, i);
- felem_mul(j, h, i);
- felem_diff(r, s2, s1);
- felem_sum(r, r, r);
- felem_mul(v, u1, i);
-
- felem_mul(z_out, tmp, h);
- felem_square(rr, r);
- felem_diff(x_out, rr, j);
- felem_diff(x_out, x_out, v);
- felem_diff(x_out, x_out, v);
-
- felem_diff(tmp, v, x_out);
- felem_mul(y_out, tmp, r);
- felem_mul(tmp, s1, j);
- felem_diff(y_out, y_out, tmp);
- felem_diff(y_out, y_out, tmp);
-}
-
-/* point_add_or_double_vartime sets {x_out,y_out,z_out} = {x1,y1,z1} +
- * {x2,y2,z2}.
- *
- * See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#addition-add-2007-bl
- *
- * This function handles the case where {x1,y1,z1}={x2,y2,z2}. */
-static void point_add_or_double_vartime(
- felem x_out, felem y_out, felem z_out, const felem x1, const felem y1,
- const felem z1, const felem x2, const felem y2, const felem z2)
-{
- felem z1z1, z1z1z1, z2z2, z2z2z2, s1, s2, u1, u2, h, i, j, r, rr,
- v, tmp;
- char x_equal, y_equal;
-
- felem_square(z1z1, z1);
- felem_square(z2z2, z2);
- felem_mul(u1, x1, z2z2);
-
- felem_sum(tmp, z1, z2);
- felem_square(tmp, tmp);
- felem_diff(tmp, tmp, z1z1);
- felem_diff(tmp, tmp, z2z2);
-
- felem_mul(z2z2z2, z2, z2z2);
- felem_mul(s1, y1, z2z2z2);
-
- felem_mul(u2, x2, z1z1);
- felem_mul(z1z1z1, z1, z1z1);
- felem_mul(s2, y2, z1z1z1);
- felem_diff(h, u2, u1);
- x_equal = felem_is_zero_vartime(h);
- felem_sum(i, h, h);
- felem_square(i, i);
- felem_mul(j, h, i);
- felem_diff(r, s2, s1);
- y_equal = felem_is_zero_vartime(r);
- if (x_equal && y_equal) {
- point_double(x_out, y_out, z_out, x1, y1, z1);
- return;
- }
- felem_sum(r, r, r);
- felem_mul(v, u1, i);
-
- felem_mul(z_out, tmp, h);
- felem_square(rr, r);
- felem_diff(x_out, rr, j);
- felem_diff(x_out, x_out, v);
- felem_diff(x_out, x_out, v);
-
- felem_diff(tmp, v, x_out);
- felem_mul(y_out, tmp, r);
- felem_mul(tmp, s1, j);
- felem_diff(y_out, y_out, tmp);
- felem_diff(y_out, y_out, tmp);
-}
-
-/* copy_conditional sets out=in if mask = 0xffffffff in constant time.
- *
- * On entry: mask is either 0 or 0xffffffff. */
-static void copy_conditional(felem out, const felem in, limb mask)
-{
- int i;
-
- for (i = 0; i < NLIMBS; i++) {
- const limb tmp = mask & (in[i] ^ out[i]);
-
- out[i] ^= tmp;
- }
-}
-
-/* select_affine_point sets {out_x,out_y} to the index'th entry of table.
- * On entry: index < 16, table[0] must be zero. */
-static void select_affine_point(felem out_x, felem out_y, const limb *table,
- limb index)
-{
- limb i, j;
-
- memset(out_x, 0, sizeof(felem));
- memset(out_y, 0, sizeof(felem));
-
- for (i = 1; i < 16; i++) {
- limb mask = i ^ index;
-
- mask |= mask >> 2;
- mask |= mask >> 1;
- mask &= 1;
- mask--;
- for (j = 0; j < NLIMBS; j++, table++)
- out_x[j] |= *table & mask;
- for (j = 0; j < NLIMBS; j++, table++)
- out_y[j] |= *table & mask;
- }
-}
-
-/* select_jacobian_point sets {out_x,out_y,out_z} to the index'th entry of
- * table. On entry: index < 16, table[0] must be zero. */
-static void select_jacobian_point(felem out_x, felem out_y, felem out_z,
- const limb *table, limb index)
-{
- limb i, j;
-
- memset(out_x, 0, sizeof(felem));
- memset(out_y, 0, sizeof(felem));
- memset(out_z, 0, sizeof(felem));
-
- /* The implicit value at index 0 is all zero. We don't need to
- * perform that iteration of the loop because we already set
- * out_* to zero. */
- table += 3 * NLIMBS;
-
- /* Hit all entries to obscure cache profiling. */
- for (i = 1; i < 16; i++) {
- limb mask = i ^ index;
-
- mask |= mask >> 2;
- mask |= mask >> 1;
- mask &= 1;
- mask--;
- for (j = 0; j < NLIMBS; j++, table++)
- out_x[j] |= *table & mask;
- for (j = 0; j < NLIMBS; j++, table++)
- out_y[j] |= *table & mask;
- for (j = 0; j < NLIMBS; j++, table++)
- out_z[j] |= *table & mask;
- }
-}
-
-/* scalar_base_mult sets {nx,ny,nz} = scalar*G where scalar is a little-endian
- * number. Note that the value of scalar must be less than the order of the
- * group. */
-static void scalar_base_mult(felem nx, felem ny, felem nz,
- const p256_int *scalar)
-{
- int i, j;
- limb n_is_infinity_mask = -1, p_is_noninfinite_mask, mask;
- u32 table_offset;
-
- felem px, py;
- felem tx, ty, tz;
-
- memset(nx, 0, sizeof(felem));
- memset(ny, 0, sizeof(felem));
- memset(nz, 0, sizeof(felem));
-
- /* The loop adds bits at positions 0, 64, 128 and 192, followed by
- * positions 32,96,160 and 224 and does this 32 times. */
- for (i = 0; i < 32; i++) {
- if (i)
- point_double(nx, ny, nz, nx, ny, nz);
-
- table_offset = 0;
- for (j = 0; j <= 32; j += 32) {
- char bit0 = p256_get_bit(scalar, 31 - i + j);
- char bit1 = p256_get_bit(scalar, 95 - i + j);
- char bit2 = p256_get_bit(scalar, 159 - i + j);
- char bit3 = p256_get_bit(scalar, 223 - i + j);
- limb index =
- bit0 | (bit1 << 1) | (bit2 << 2) | (bit3 << 3);
-
- select_affine_point(px, py,
- kPrecomputed + table_offset, index);
- table_offset += 30 * NLIMBS;
-
- /* Since scalar is less than the order of the
- * group, we know that {nx,ny,nz} !=
- * {px,py,1}, unless both are zero, which we
- * handle below. */
- point_add_mixed(tx, ty, tz, nx, ny, nz, px, py);
- /* The result of point_add_mixed is incorrect
- * if {nx,ny,nz} is zero (a.k.a. the point at
- * infinity). We handle that situation by
- * copying the point from the table. */
- copy_conditional(nx, px, n_is_infinity_mask);
- copy_conditional(ny, py, n_is_infinity_mask);
- copy_conditional(nz, kOne, n_is_infinity_mask);
-
- /* Equally, the result is also wrong if the
- * point from the table is zero, which happens
- * when the index is zero. We handle that by
- * only copying from {tx,ty,tz} to {nx,ny,nz}
- * if index != 0. */
- p_is_noninfinite_mask = NON_ZERO_TO_ALL_ONES(index);
- mask = p_is_noninfinite_mask & ~n_is_infinity_mask;
- copy_conditional(nx, tx, mask);
- copy_conditional(ny, ty, mask);
- copy_conditional(nz, tz, mask);
- /* If p was not zero, then n is now non-zero. */
- n_is_infinity_mask &= ~p_is_noninfinite_mask;
- }
- }
-}
-
-/* point_to_affine converts a Jacobian point to an affine point. If
- * the input is the point at infinity then it returns (0, 0) in
- * constant time. */
-static void point_to_affine(felem x_out, felem y_out, const felem nx,
- const felem ny, const felem nz)
-{
- felem z_inv, z_inv_sq;
-
- felem_inv(z_inv, nz);
- felem_square(z_inv_sq, z_inv);
- felem_mul(x_out, nx, z_inv_sq);
- felem_mul(z_inv, z_inv, z_inv_sq);
- felem_mul(y_out, ny, z_inv);
-}
-
-/* scalar_base_mult sets {nx,ny,nz} = scalar*{x,y}. */
-static void scalar_mult(felem nx, felem ny, felem nz, const felem x,
- const felem y, const p256_int *scalar)
-{
- int i;
- felem px, py, pz, tx, ty, tz;
- felem precomp[16][3];
- limb n_is_infinity_mask, index, p_is_noninfinite_mask, mask;
-
- /* We precompute 0,1,2,... times {x,y}. */
- memset(precomp, 0, sizeof(felem) * 3);
- memcpy(&precomp[1][0], x, sizeof(felem));
- memcpy(&precomp[1][1], y, sizeof(felem));
- memcpy(&precomp[1][2], kOne, sizeof(felem));
-
- for (i = 2; i < 16; i += 2) {
- point_double(precomp[i][0], precomp[i][1], precomp[i][2],
- precomp[i / 2][0], precomp[i / 2][1],
- precomp[i / 2][2]);
-
- point_add_mixed(
- precomp[i + 1][0], precomp[i + 1][1], precomp[i + 1][2],
- precomp[i][0], precomp[i][1], precomp[i][2], x, y);
- }
-
- memset(nx, 0, sizeof(felem));
- memset(ny, 0, sizeof(felem));
- memset(nz, 0, sizeof(felem));
- n_is_infinity_mask = -1;
-
- /* We add in a window of four bits each iteration and do this
- * 64 times. */
- for (i = 0; i < 256; i += 4) {
- if (i) {
- point_double(nx, ny, nz, nx, ny, nz);
- point_double(nx, ny, nz, nx, ny, nz);
- point_double(nx, ny, nz, nx, ny, nz);
- point_double(nx, ny, nz, nx, ny, nz);
- }
-
- index = (p256_get_bit(scalar, 255 - i - 0) << 3) |
- (p256_get_bit(scalar, 255 - i - 1) << 2) |
- (p256_get_bit(scalar, 255 - i - 2) << 1) |
- p256_get_bit(scalar, 255 - i - 3);
-
- /* See the comments in scalar_base_mult about handling
- * infinities. */
- select_jacobian_point(px, py, pz, precomp[0][0], index);
- point_add(tx, ty, tz, nx, ny, nz, px, py, pz);
- copy_conditional(nx, px, n_is_infinity_mask);
- copy_conditional(ny, py, n_is_infinity_mask);
- copy_conditional(nz, pz, n_is_infinity_mask);
-
- p_is_noninfinite_mask = NON_ZERO_TO_ALL_ONES(index);
- mask = p_is_noninfinite_mask & ~n_is_infinity_mask;
-
- copy_conditional(nx, tx, mask);
- copy_conditional(ny, ty, mask);
- copy_conditional(nz, tz, mask);
- n_is_infinity_mask &= ~p_is_noninfinite_mask;
- }
-}
-
-/* 2^257 mod p256.p */
-#define kRDigits {2, 0, 0, 0xfffffffe, 0xffffffff, 0xffffffff, 0xfffffffd, 1}
-/* 1 / 2^257 mod p256.p */
-#define kRInvDigits {0x80000000, 1, 0xffffffff, 0, 0x80000001, 0xfffffffe, \
- 1, 0x7fffffff}
-
-static const p256_int kR = { kRDigits };
-static const p256_int kRInv = { kRInvDigits };
-
-/* to_montgomery sets out = R*in. */
-static void to_montgomery(felem out, const p256_int *in)
-{
- p256_int in_shifted;
- int i;
-
- p256_init(&in_shifted);
- p256_modmul(&SECP256r1_p, in, 0, &kR, &in_shifted);
-
- for (i = 0; i < NLIMBS; i++) {
- if ((i & 1) == 0) {
- out[i] = P256_DIGIT(&in_shifted, 0) & kBottom29Bits;
- p256_shr(&in_shifted, 29, &in_shifted);
- } else {
- out[i] = P256_DIGIT(&in_shifted, 0) & kBottom28Bits;
- p256_shr(&in_shifted, 28, &in_shifted);
- }
- }
-
- p256_clear(&in_shifted);
-}
-
-/* from_montgomery sets out=in/R. */
-static void from_montgomery(p256_int *out, const felem in)
-{
- p256_int result, tmp;
- int i, top;
-
- p256_init(&result);
- p256_init(&tmp);
-
- p256_add_d(&tmp, in[NLIMBS - 1], &result);
- for (i = NLIMBS - 2; i >= 0; i--) {
- if ((i & 1) == 0)
- top = p256_shl(&result, 29, &tmp);
- else
- top = p256_shl(&result, 28, &tmp);
-
- top |= p256_add_d(&tmp, in[i], &result);
- }
-
- p256_modmul(&SECP256r1_p, &kRInv, top, &result, out);
+#include <stdint.h>
- p256_clear(&result);
- p256_clear(&tmp);
-}
+#include "cryptoc/p256.h"
/* p256_base_point_mul sets {out_x,out_y} = nG, where n is < the
* order of the group. */
int DCRYPTO_p256_base_point_mul(p256_int *out_x, p256_int *out_y,
const p256_int *n)
{
- felem x, y, z;
-
if (p256_is_zero(n) != 0) {
p256_clear(out_x);
p256_clear(out_y);
return 0;
}
- scalar_base_mult(x, y, z, n);
-
- {
- felem x_affine, y_affine;
-
- point_to_affine(x_affine, y_affine, x, y, z);
- from_montgomery(out_x, x_affine);
- from_montgomery(out_y, y_affine);
- }
-
+ p256_base_point_mul(n, out_x, out_y);
return 1;
}
-/* p256_point_mul sets {out_x,out_y} = n*{in_x,in_y}, where n is <
- * the order of the group. */
-void p256_point_mul(const p256_int *n, const p256_int *in_x,
- const p256_int *in_y, p256_int *out_x, p256_int *out_y)
-{
- felem x, y, z, px, py;
-
- to_montgomery(px, in_x);
- to_montgomery(py, in_y);
-
- scalar_mult(x, y, z, px, py, n);
-
- point_to_affine(px, py, x, y, z);
- from_montgomery(out_x, px);
- from_montgomery(out_y, py);
-}
-
-/* p256_points_mul_vartime sets {out_x,out_y} = n1*G + n2*{in_x,in_y}, where
- * n1 and n2 are < the order of the group.
- *
- * As indicated by the name, this function operates in variable time. This
- * is safe because it's used for signature validation which doesn't deal
- * with secrets. */
-void p256_points_mul_vartime(
- const p256_int *n1, const p256_int *n2, const p256_int *in_x,
- const p256_int *in_y, p256_int *out_x, p256_int *out_y)
-{
- felem x1, y1, z1, x2, y2, z2, px, py;
-
- /* If both scalars are zero, then the result is the point at
- * infinity. */
- if (p256_is_zero(n1) != 0 && p256_is_zero(n2) != 0) {
- p256_clear(out_x);
- p256_clear(out_y);
- return;
- }
-
- to_montgomery(px, in_x);
- to_montgomery(py, in_y);
- scalar_base_mult(x1, y1, z1, n1);
- scalar_mult(x2, y2, z2, px, py, n2);
-
- if (p256_is_zero(n2) != 0) {
- /* If n2 == 0, then {x2,y2,z2} is zero and the result is just
- * {x1,y1,z1}. */
- } else if (p256_is_zero(n1) != 0) {
- /* If n1 == 0, then {x1,y1,z1} is zero and the result is just
- * {x2,y2,z2}. */
- memcpy(x1, x2, sizeof(x2));
- memcpy(y1, y2, sizeof(y2));
- memcpy(z1, z2, sizeof(z2));
- } else {
- /* This function handles the case where {x1,y1,z1} ==
- * {x2,y2,z2}. */
- point_add_or_double_vartime(x1, y1, z1, x1, y1, z1, x2, y2, z2);
- }
-
- point_to_affine(px, py, x1, y1, z1);
- from_montgomery(out_x, px);
- from_montgomery(out_y, py);
-}
-
/* DCRYPTO_p256_point_mul sets {out_x,out_y} = n*{in_x,in_y}, where n is <
* the order of the group. */
int DCRYPTO_p256_point_mul(p256_int *out_x, p256_int *out_y,
diff --git a/chip/g/dcrypto/p256_ecdsa.c b/chip/g/dcrypto/p256_ecdsa.c
deleted file mode 100644
index 2385c58d62..0000000000
--- a/chip/g/dcrypto/p256_ecdsa.c
+++ /dev/null
@@ -1,103 +0,0 @@
-/* Copyright 2015 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include <stdint.h>
-
-#include "dcrypto.h"
-
-/* Compute k based on a given {key, digest} pair, 0 < k < n. */
-static void determine_k(const p256_int *key, const p256_int *digest,
- char *tweak, p256_int *k)
-{
- do {
- p256_int p1, p2;
- struct HMAC_CTX hmac;
-
- /* NOTE: taking the p256_int in-memory representation
- * is not endian neutral. Signatures with an
- * identical key on identical digests will differ per
- * host endianness. This however does not jeopardize
- * the key bits. */
- dcrypto_HMAC_SHA256_init(&hmac, key, P256_NBYTES);
- dcrypto_HMAC_update(&hmac, tweak, 1);
- dcrypto_HMAC_update(&hmac, (uint8_t *) digest, P256_NBYTES);
- ++(*tweak);
- p256_from_bin(dcrypto_HMAC_final(&hmac), &p1);
-
- dcrypto_HMAC_SHA256_init(&hmac, key, P256_NBYTES);
- dcrypto_HMAC_update(&hmac, tweak, 1);
- dcrypto_HMAC_update(&hmac, (uint8_t *) digest, P256_NBYTES);
- ++(*tweak);
- p256_from_bin(dcrypto_HMAC_final(&hmac), &p2);
-
- /* Combine p1 and p2 into well distributed k. */
- p256_modmul(&SECP256r1_n, &p1, 0, &p2, k);
-
- /* (Attempt to) clear stack state. */
- p256_clear(&p1);
- p256_clear(&p2);
-
- } while (p256_is_zero(k));
-}
-
-void DCRYPTO_p256_ecdsa_sign(const p256_int *key, const p256_int *digest,
- p256_int *r, p256_int *s)
-{
- char tweak = 'A';
- p256_digit top;
-
- for (;;) {
- p256_int k, kinv;
-
- determine_k(key, digest, &tweak, &k);
- DCRYPTO_p256_base_point_mul(r, s, &k);
- p256_mod(&SECP256r1_n, r, r);
-
- /* Make sure r != 0. */
- if (p256_is_zero(r))
- continue;
-
- p256_modmul(&SECP256r1_n, r, 0, key, s);
- top = p256_add(s, digest, s);
- p256_modinv(&SECP256r1_n, &k, &kinv);
- p256_modmul(&SECP256r1_n, &kinv, top, s, s);
-
- /* (Attempt to) clear stack state. */
- p256_clear(&k);
- p256_clear(&kinv);
-
- /* Make sure s != 0. */
- if (p256_is_zero(s))
- continue;
-
- break;
- }
-}
-
-int DCRYPTO_p256_ecdsa_verify(const p256_int *key_x, const p256_int *key_y,
- const p256_int *digest,
- const p256_int *r, const p256_int *s)
-{
- p256_int u, v;
-
- /* Check public key. */
- if (!DCRYPTO_p256_valid_point(key_x, key_y))
- return 0;
-
- /* Check r and s are != 0 % n. */
- p256_mod(&SECP256r1_n, r, &u);
- p256_mod(&SECP256r1_n, s, &v);
- if (p256_is_zero(&u) || p256_is_zero(&v))
- return 0;
-
- p256_modinv_vartime(&SECP256r1_n, s, &v);
- p256_modmul(&SECP256r1_n, digest, 0, &v, &u); /* digest / s % n */
- p256_modmul(&SECP256r1_n, r, 0, &v, &v); /* r / s % n */
-
- p256_points_mul_vartime(&u, &v, key_x, key_y, &u, &v);
-
- p256_mod(&SECP256r1_n, &u, &u); /* (x coord % p) % n */
- return p256_cmp(r, &u) == 0;
-}
diff --git a/chip/g/dcrypto/p256_ecies.c b/chip/g/dcrypto/p256_ecies.c
index 2251c551a6..8272014495 100644
--- a/chip/g/dcrypto/p256_ecies.c
+++ b/chip/g/dcrypto/p256_ecies.c
@@ -7,6 +7,10 @@
#include "dcrypto.h"
#include "trng.h"
+#include "util.h"
+
+#include "cryptoc/p256.h"
+#include "cryptoc/sha256.h"
#define AES_KEY_BYTES 16
#define HMAC_KEY_BYTES 32
@@ -35,14 +39,14 @@ size_t DCRYPTO_ecies_encrypt(
uint8_t key[AES_KEY_BYTES + HMAC_KEY_BYTES];
const uint8_t *aes_key;
const uint8_t *hmac_key;
- struct HMAC_CTX ctx;
+ LITE_HMAC_CTX ctx;
uint8_t *outp = out;
uint8_t *ciphertext;
if (auth_data_len > in_len)
return 0;
if (out_len < 1 + P256_NBYTES + P256_NBYTES +
- in_len + SHA256_DIGEST_BYTES)
+ in_len + SHA256_DIGEST_SIZE)
return 0;
/* Generate emphemeral EC key. */
@@ -54,7 +58,7 @@ size_t DCRYPTO_ecies_encrypt(
&eph_d, pub_x, pub_y))
return 0;
/* Check for computational errors. */
- if (!DCRYPTO_p256_valid_point(&secret_x, &secret_y))
+ if (!p256_is_valid_point(&secret_x, &secret_y))
return 0;
/* Convert secret to big-endian. */
reverse(&secret_x, sizeof(secret_x));
@@ -94,11 +98,11 @@ size_t DCRYPTO_ecies_encrypt(
outp += P256_NBYTES;
/* Calculate HMAC(auth_data || ciphertext). */
- dcrypto_HMAC_SHA256_init(&ctx, hmac_key, HMAC_KEY_BYTES);
- dcrypto_HMAC_update(&ctx, outp, in_len);
+ DCRYPTO_HMAC_SHA256_init(&ctx, hmac_key, HMAC_KEY_BYTES);
+ HASH_update(&ctx.hash, outp, in_len);
outp += in_len;
- memcpy(outp, dcrypto_HMAC_final(&ctx), SHA256_DIGEST_BYTES);
- outp += SHA256_DIGEST_BYTES;
+ memcpy(outp, DCRYPTO_HMAC_final(&ctx), SHA256_DIGEST_SIZE);
+ outp += SHA256_DIGEST_SIZE;
return outp - (uint8_t *) out;
}
@@ -117,17 +121,17 @@ size_t DCRYPTO_ecies_decrypt(
uint8_t key[AES_KEY_BYTES + HMAC_KEY_BYTES];
const uint8_t *aes_key;
const uint8_t *hmac_key;
- struct HMAC_CTX ctx;
+ LITE_HMAC_CTX ctx;
const uint8_t *inp = in;
uint8_t *outp = out;
if (in_len < 1 + P256_NBYTES + P256_NBYTES + auth_data_len +
- SHA256_DIGEST_BYTES)
+ SHA256_DIGEST_SIZE)
return 0;
if (inp[0] != 0x04)
return 0;
- in_len -= 1 + P256_NBYTES + P256_NBYTES + SHA256_DIGEST_BYTES;
+ in_len -= 1 + P256_NBYTES + P256_NBYTES + SHA256_DIGEST_SIZE;
inp++;
p256_from_bin(inp, &eph_x);
@@ -136,14 +140,14 @@ size_t DCRYPTO_ecies_decrypt(
inp += P256_NBYTES;
/* Verify that the public point is on the curve. */
- if (!DCRYPTO_p256_valid_point(&eph_x, &eph_y))
+ if (!p256_is_valid_point(&eph_x, &eph_y))
return 0;
/* Compute the DH point. */
if (!DCRYPTO_p256_point_mul(&secret_x, &secret_y,
d, &eph_x, &eph_y))
return 0;
/* Check for computational errors. */
- if (!DCRYPTO_p256_valid_point(&secret_x, &secret_y))
+ if (!p256_is_valid_point(&secret_x, &secret_y))
return 0;
/* Convert secret to big-endian. */
reverse(&secret_x, sizeof(secret_x));
@@ -155,11 +159,11 @@ size_t DCRYPTO_ecies_decrypt(
aes_key = &key[0];
hmac_key = &key[AES_KEY_BYTES];
- dcrypto_HMAC_SHA256_init(&ctx, hmac_key, HMAC_KEY_BYTES);
- dcrypto_HMAC_update(&ctx, inp, in_len);
+ DCRYPTO_HMAC_SHA256_init(&ctx, hmac_key, HMAC_KEY_BYTES);
+ HASH_update(&ctx.hash, inp, in_len);
/* TODO(ngm): replace with constant time verify. */
- if (memcmp(inp + in_len, dcrypto_HMAC_final(&ctx),
- SHA256_DIGEST_BYTES) != 0)
+ if (memcmp(inp + in_len, DCRYPTO_HMAC_final(&ctx),
+ SHA256_DIGEST_SIZE) != 0)
return 0;
memmove(outp, inp, auth_data_len);
diff --git a/chip/g/dcrypto/rsa.c b/chip/g/dcrypto/rsa.c
index 5df3821413..e141f9f501 100644
--- a/chip/g/dcrypto/rsa.c
+++ b/chip/g/dcrypto/rsa.c
@@ -11,11 +11,14 @@
#include <assert.h>
+#include "cryptoc/sha.h"
+#include "cryptoc/sha256.h"
+
static void MGF1_xor(uint8_t *dst, uint32_t dst_len,
const uint8_t *seed, uint32_t seed_len,
enum hashing_mode hashing)
{
- struct HASH_CTX ctx;
+ HASH_CTX ctx;
struct {
uint8_t b3;
uint8_t b2;
@@ -23,8 +26,8 @@ static void MGF1_xor(uint8_t *dst, uint32_t dst_len,
uint8_t b0;
} cnt;
const uint8_t *digest;
- const size_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const size_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
cnt.b0 = cnt.b1 = cnt.b2 = cnt.b3 = 0;
while (dst_len) {
@@ -35,9 +38,9 @@ static void MGF1_xor(uint8_t *dst, uint32_t dst_len,
else
DCRYPTO_SHA256_init(&ctx, 0);
- DCRYPTO_HASH_update(&ctx, seed, seed_len);
- DCRYPTO_HASH_update(&ctx, (uint8_t *) &cnt, sizeof(cnt));
- digest = DCRYPTO_HASH_final(&ctx);
+ HASH_update(&ctx, seed, seed_len);
+ HASH_update(&ctx, (uint8_t *) &cnt, sizeof(cnt));
+ digest = HASH_final(&ctx);
for (i = 0; i < dst_len && i < hash_size; ++i)
*dst++ ^= *digest++;
dst_len -= i;
@@ -62,8 +65,8 @@ static int oaep_pad(uint8_t *output, uint32_t output_len,
enum hashing_mode hashing, const char *label)
{
int i;
- const size_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const size_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
uint8_t *const seed = output + 1;
uint8_t *const phash = seed + hash_size;
uint8_t *const PS = phash + hash_size;
@@ -92,8 +95,8 @@ static int oaep_pad(uint8_t *output, uint32_t output_len,
else
DCRYPTO_SHA256_init(&ctx, 0);
- DCRYPTO_HASH_update(&ctx, label, label ? strlen(label) + 1 : 0);
- memcpy(phash, DCRYPTO_HASH_final(&ctx), hash_size);
+ HASH_update(&ctx, label, label ? strlen(label) + 1 : 0);
+ memcpy(phash, HASH_final(&ctx), hash_size);
*one = 1;
memcpy(one + 1, msg, msg_len);
MGF1_xor(phash, hash_size + 1 + max_msg_len,
@@ -109,8 +112,8 @@ static int check_oaep_pad(uint8_t *out, uint32_t *out_len,
uint8_t *padded, uint32_t padded_len,
enum hashing_mode hashing, const char *label)
{
- const size_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const size_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
uint8_t *seed = padded + 1;
uint8_t *phash = seed + hash_size;
uint8_t *PS = phash + hash_size;
@@ -132,9 +135,9 @@ static int check_oaep_pad(uint8_t *out, uint32_t *out_len,
DCRYPTO_SHA1_init(&ctx, 0);
else
DCRYPTO_SHA256_init(&ctx, 0);
- DCRYPTO_HASH_update(&ctx, label, label ? strlen(label) + 1 : 0);
+ HASH_update(&ctx, label, label ? strlen(label) + 1 : 0);
- bad = memcmp(phash, DCRYPTO_HASH_final(&ctx), hash_size);
+ bad = memcmp(phash, HASH_final(&ctx), hash_size);
bad |= padded[0];
for (i = PS - padded; i < padded_len; i++) {
@@ -239,8 +242,8 @@ static int pkcs1_type1_pad(uint8_t *padded, uint32_t padded_len,
: &SHA256_DER[0];
const uint32_t der_size = (hashing == HASH_SHA1) ? sizeof(SHA1_DER)
: sizeof(SHA256_DER);
- const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
uint32_t ps_len;
if (padded_len < RSA_PKCS1_PADDING_SIZE + der_size)
@@ -273,8 +276,8 @@ static int check_pkcs1_type1_pad(const uint8_t *msg, uint32_t msg_len,
: &SHA256_DER[0];
const uint32_t der_size = (hashing == HASH_SHA1) ? sizeof(SHA1_DER)
: sizeof(SHA256_DER);
- const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
uint32_t ps_len;
if (msg_len != hash_size)
@@ -303,8 +306,8 @@ static int pkcs1_pss_pad(uint8_t *padded, uint32_t padded_len,
const uint8_t *in, uint32_t in_len,
enum hashing_mode hashing)
{
- const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
const uint32_t salt_len = MIN(padded_len - hash_size - 2, hash_size);
uint32_t db_len;
uint32_t ps_len;
@@ -323,14 +326,14 @@ static int pkcs1_pss_pad(uint8_t *padded, uint32_t padded_len,
/* Pilfer bits of output for temporary use. */
memset(padded, 0, 8);
- DCRYPTO_HASH_update(&ctx, padded, 8);
- DCRYPTO_HASH_update(&ctx, in, in_len);
+ HASH_update(&ctx, padded, 8);
+ HASH_update(&ctx, in, in_len);
/* Pilfer bits of output for temporary use. */
rand_bytes(padded, salt_len);
- DCRYPTO_HASH_update(&ctx, padded, salt_len);
+ HASH_update(&ctx, padded, salt_len);
/* Output hash. */
- memcpy(padded + db_len, DCRYPTO_HASH_final(&ctx), hash_size);
+ memcpy(padded + db_len, HASH_final(&ctx), hash_size);
/* Prepare DB. */
ps_len = db_len - salt_len - 1;
@@ -351,13 +354,13 @@ static int check_pkcs1_pss_pad(const uint8_t *in, uint32_t in_len,
uint8_t *padded, uint32_t padded_len,
enum hashing_mode hashing)
{
- const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA1_DIGEST_BYTES
- : SHA256_DIGEST_BYTES;
+ const uint32_t hash_size = (hashing == HASH_SHA1) ? SHA_DIGEST_SIZE
+ : SHA256_DIGEST_SIZE;
const uint8_t zeros[8] = {0, 0, 0, 0, 0, 0, 0, 0};
uint32_t db_len;
uint32_t max_ps_len;
uint32_t salt_len;
- struct HASH_CTX ctx;
+ HASH_CTX ctx;
int bad = 0;
int i;
@@ -392,10 +395,10 @@ static int check_pkcs1_pss_pad(const uint8_t *in, uint32_t in_len,
DCRYPTO_SHA1_init(&ctx, 0);
else
DCRYPTO_SHA256_init(&ctx, 0);
- DCRYPTO_HASH_update(&ctx, zeros, sizeof(zeros));
- DCRYPTO_HASH_update(&ctx, in, in_len);
- DCRYPTO_HASH_update(&ctx, padded + db_len - salt_len, salt_len);
- bad |= memcmp(padded + db_len, DCRYPTO_HASH_final(&ctx), hash_size);
+ HASH_update(&ctx, zeros, sizeof(zeros));
+ HASH_update(&ctx, in, in_len);
+ HASH_update(&ctx, padded + db_len - salt_len, salt_len);
+ bad |= memcmp(padded + db_len, HASH_final(&ctx), hash_size);
return !bad;
}
diff --git a/chip/g/dcrypto/sha1.c b/chip/g/dcrypto/sha1.c
index 9721a9c2d9..07ef3a34ef 100644
--- a/chip/g/dcrypto/sha1.c
+++ b/chip/g/dcrypto/sha1.c
@@ -7,59 +7,29 @@
#include "internal.h"
#include "registers.h"
-static void sw_sha1_init(SHA1_CTX *ctx);
-static void sw_sha1_update(SHA1_CTX *ctx, const uint8_t *data, uint32_t len);
-static const uint8_t *sw_sha1_final(SHA1_CTX *ctx);
-static const uint8_t *sha1_hash(const uint8_t *data, uint32_t len,
- uint8_t *digest);
-static const uint8_t *dcrypto_sha1_final(SHA1_CTX *unused);
-
-/* Software SHA1 implementation. */
-static const struct HASH_VTAB SW_SHA1_VTAB = {
- sw_sha1_update,
- sw_sha1_final,
- sha1_hash,
- SHA1_DIGEST_BYTES
-};
-
-static void sw_sha1_init(SHA1_CTX *ctx)
-{
- ctx->vtab = &SW_SHA1_VTAB;
- sha1_init(&ctx->u.sw_sha1);
-}
-
-static void sw_sha1_update(SHA1_CTX *ctx, const uint8_t *data, uint32_t len)
-{
- sha1_update(&ctx->u.sw_sha1, data, len);
-}
-
-static const uint8_t *sw_sha1_final(SHA1_CTX *ctx)
-{
- return sha1_final(&ctx->u.sw_sha1);
-}
-
-static const uint8_t *sha1_hash(const uint8_t *data, uint32_t len,
- uint8_t *digest)
-{
- SHA1_CTX ctx;
-
- sw_sha1_init(&ctx);
- sw_sha1_update(&ctx, data, len);
- memcpy(digest, sw_sha1_final(&ctx), SHA1_DIGEST_BYTES);
- return digest;
-}
+#include "cryptoc/sha.h"
+static void dcrypto_sha1_init(SHA_CTX *ctx);
+static const uint8_t *dcrypto_sha1_final(SHA_CTX *unused);
/*
* Hardware SHA implementation.
*/
-static const struct HASH_VTAB HW_SHA1_VTAB = {
+static const HASH_VTAB HW_SHA1_VTAB = {
+ dcrypto_sha1_init,
dcrypto_sha_update,
dcrypto_sha1_final,
DCRYPTO_SHA1_hash,
- SHA1_DIGEST_BYTES
+ SHA_DIGEST_SIZE
};
+/* Requires dcrypto_grab_sha_hw() to be called first. */
+static void dcrypto_sha1_init(SHA_CTX *ctx)
+{
+ ctx->f = &HW_SHA1_VTAB;
+ dcrypto_sha_init(SHA1_MODE);
+}
+
/* Select and initialize either the software or hardware
* implementation. If "multi-threaded" behaviour is required, then
* callers must set sw_required to 1. This is because SHA1 state
@@ -69,30 +39,27 @@ static const struct HASH_VTAB HW_SHA1_VTAB = {
* If the caller has no preference as to implementation, then hardware
* is preferred based on availability. Hardware is considered to be
* in use between init() and finished() calls. */
-void DCRYPTO_SHA1_init(SHA1_CTX *ctx, uint32_t sw_required)
+void DCRYPTO_SHA1_init(SHA_CTX *ctx, uint32_t sw_required)
{
- if (!sw_required && dcrypto_grab_sha_hw()) {
- ctx->vtab = &HW_SHA1_VTAB;
- dcrypto_sha_init(SHA1_MODE);
- } else {
- sw_sha1_init(ctx);
- }
+ if (!sw_required && dcrypto_grab_sha_hw())
+ dcrypto_sha1_init(ctx);
+ else
+ SHA_init(ctx);
}
-static const uint8_t *dcrypto_sha1_final(SHA1_CTX *ctx)
+static const uint8_t *dcrypto_sha1_final(SHA_CTX *ctx)
{
- dcrypto_sha_wait(SHA1_MODE, (uint32_t *) ctx->u.buf);
- return ctx->u.buf;
+ dcrypto_sha_wait(SHA1_MODE, (uint32_t *) ctx->buf);
+ return ctx->buf;
}
-const uint8_t *DCRYPTO_SHA1_hash(const uint8_t *data, uint32_t n,
+const uint8_t *DCRYPTO_SHA1_hash(const void *data, uint32_t n,
uint8_t *digest)
{
if (dcrypto_grab_sha_hw())
/* dcrypto_sha_wait() will release the hw. */
dcrypto_sha_hash(SHA1_MODE, data, n, digest);
else
- sha1_hash(data, n, digest);
+ SHA_hash(data, n, digest);
return digest;
}
-
diff --git a/chip/g/dcrypto/sha256.c b/chip/g/dcrypto/sha256.c
index c884ff2a4a..e3ac6642bb 100644
--- a/chip/g/dcrypto/sha256.c
+++ b/chip/g/dcrypto/sha256.c
@@ -8,7 +8,10 @@
#include "registers.h"
#include "util.h"
-static const uint8_t *dcrypto_sha256_final(SHA256_CTX *ctx);
+#include "cryptoc/sha256.h"
+
+static void dcrypto_sha256_init(LITE_SHA256_CTX *ctx);
+static const uint8_t *dcrypto_sha256_final(LITE_SHA256_CTX *ctx);
#ifdef SECTION_IS_RO
/* RO is single threaded. */
@@ -25,46 +28,6 @@ static inline void dcrypto_release_sha_hw(void)
#include "task.h"
static struct mutex hw_busy_mutex;
-static void sha256_init(SHA256_CTX *ctx);
-static void sha256_update(SHA256_CTX *ctx, const uint8_t *data, uint32_t len);
-static const uint8_t *sha256_final(SHA256_CTX *ctx);
-static const uint8_t *sha256_hash(const uint8_t *data, uint32_t len,
- uint8_t *digest);
-
-static const struct HASH_VTAB SW_SHA256_VTAB = {
- sha256_update,
- sha256_final,
- sha256_hash,
- SHA256_DIGEST_BYTES
-};
-
-static void sha256_init(SHA256_CTX *ctx)
-{
- ctx->vtab = &SW_SHA256_VTAB;
- SHA256_init(&ctx->u.sw_sha256);
-}
-
-static void sha256_update(SHA256_CTX *ctx, const uint8_t *data, uint32_t len)
-{
- SHA256_update(&ctx->u.sw_sha256, data, len);
-}
-
-static const uint8_t *sha256_final(SHA256_CTX *ctx)
-{
- return SHA256_final(&ctx->u.sw_sha256);
-}
-
-static const uint8_t *sha256_hash(const uint8_t *data, uint32_t len,
- uint8_t *digest)
-{
- SHA256_CTX ctx;
-
- sha256_init(&ctx);
- sha256_update(&ctx, data, len);
- memcpy(digest, sha256_final(&ctx), SHA256_DIGEST_BYTES);
- return digest;
-}
-
static int hw_busy;
int dcrypto_grab_sha_hw(void)
@@ -94,8 +57,8 @@ void dcrypto_sha_wait(enum sha_mode mode, uint32_t *digest)
{
int i;
const int digest_len = (mode == SHA1_MODE) ?
- SHA1_DIGEST_BYTES :
- SHA256_DIGEST_BYTES;
+ SHA_DIGEST_SIZE :
+ SHA256_DIGEST_SIZE;
/* Stop LIVESTREAM mode. */
GWRITE_FIELD(KEYMGR, SHA_TRIG, TRIG_STOP, 1);
@@ -110,11 +73,12 @@ void dcrypto_sha_wait(enum sha_mode mode, uint32_t *digest)
}
/* Hardware SHA implementation. */
-static const struct HASH_VTAB HW_SHA256_VTAB = {
+static const HASH_VTAB HW_SHA256_VTAB = {
+ dcrypto_sha256_init,
dcrypto_sha_update,
dcrypto_sha256_final,
DCRYPTO_SHA256_hash,
- SHA256_DIGEST_BYTES
+ SHA256_DIGEST_SIZE
};
void dcrypto_sha_hash(enum sha_mode mode, const uint8_t *data, uint32_t n,
@@ -126,7 +90,7 @@ void dcrypto_sha_hash(enum sha_mode mode, const uint8_t *data, uint32_t n,
}
void dcrypto_sha_update(struct HASH_CTX *unused,
- const uint8_t *data, uint32_t n)
+ const void *data, uint32_t n)
{
const uint8_t *bp = (const uint8_t *) data;
const uint32_t *wp;
@@ -180,25 +144,30 @@ void dcrypto_sha_init(enum sha_mode mode)
GWRITE_FIELD(KEYMGR, SHA_TRIG, TRIG_GO, 1);
}
-void DCRYPTO_SHA256_init(SHA256_CTX *ctx, uint32_t sw_required)
+static void dcrypto_sha256_init(LITE_SHA256_CTX *ctx)
{
- if (!sw_required && dcrypto_grab_sha_hw()) {
- ctx->vtab = &HW_SHA256_VTAB;
- dcrypto_sha_init(SHA256_MODE);
- }
+ ctx->f = &HW_SHA256_VTAB;
+ dcrypto_sha_init(SHA256_MODE);
+}
+
+/* Requires dcrypto_grab_sha_hw() to be called first. */
+void DCRYPTO_SHA256_init(LITE_SHA256_CTX *ctx, uint32_t sw_required)
+{
+ if (!sw_required && dcrypto_grab_sha_hw())
+ dcrypto_sha256_init(ctx);
#ifndef SECTION_IS_RO
else
- sha256_init(ctx);
+ SHA256_init(ctx);
#endif
}
-static const uint8_t *dcrypto_sha256_final(SHA256_CTX *ctx)
+static const uint8_t *dcrypto_sha256_final(LITE_SHA256_CTX *ctx)
{
- dcrypto_sha_wait(SHA256_MODE, (uint32_t *) ctx->u.buf);
- return ctx->u.buf;
+ dcrypto_sha_wait(SHA256_MODE, (uint32_t *) ctx->buf);
+ return ctx->buf;
}
-const uint8_t *DCRYPTO_SHA256_hash(const uint8_t *data, uint32_t n,
+const uint8_t *DCRYPTO_SHA256_hash(const void *data, uint32_t n,
uint8_t *digest)
{
if (dcrypto_grab_sha_hw())
@@ -206,7 +175,7 @@ const uint8_t *DCRYPTO_SHA256_hash(const uint8_t *data, uint32_t n,
dcrypto_sha_hash(SHA256_MODE, data, n, digest);
#ifndef SECTION_IS_RO
else
- sha256_hash(data, n, digest);
+ SHA256_hash(data, n, digest);
#endif
return digest;
}
diff --git a/chip/g/upgrade_fw.c b/chip/g/upgrade_fw.c
index 8cc2f2ceda..045a934448 100644
--- a/chip/g/upgrade_fw.c
+++ b/chip/g/upgrade_fw.c
@@ -11,9 +11,10 @@
#include "hooks.h"
#include "include/compile_time_macros.h"
#include "memory.h"
-#include "sha1.h"
#include "uart.h"
+#include "cryptoc/sha.h"
+
#define CPRINTF(format, args...) cprintf(CC_EXTENSION, format, ## args)
/* Various upgrade extension command return values. */
@@ -91,7 +92,7 @@ void fw_upgrade_command_handler(void *body,
{
struct upgrade_command *cmd_body = body;
uint8_t *rv = body;
- uint8_t sha1_digest[SHA1_DIGEST_SIZE];
+ uint8_t sha1_digest[SHA_DIGEST_SIZE];
size_t body_size;
uint32_t block_offset;
diff --git a/include/config.h b/include/config.h
index 0addbc1a1e..5f527d8ebe 100644
--- a/include/config.h
+++ b/include/config.h
@@ -1566,8 +1566,6 @@
/* Support computing of other hash sizes (without the VBOOT code) */
#undef CONFIG_SHA256
-#undef CONFIG_SHA384
-#undef CONFIG_SHA512
/* Emulate the CLZ (Count Leading Zeros) in software for CPU lacking support */
#undef CONFIG_SOFTWARE_CLZ
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