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mirror of https://git.tartarus.org/simon/putty.git synced 2025-01-09 09:27:59 +00:00
putty-source/sshsh256.c
Simon Tatham baff23cdd6 Centralised HMAC implementation.
This replaces all the separate HMAC-implementing wrappers in the
various source files implementing the underlying hashes.

The new HMAC code also correctly handles the case of a key longer than
the underlying hash's block length, by replacing it with its own hash.
This means I can reinstate the test vectors in RFC 6234 which exercise
that case, which I didn't add to cryptsuite before because they'd have
failed.

It also allows me to remove the ad-hoc code at the call site in
cproxy.c which turns out to have been doing the same thing - I think
that must have been the only call site where the question came up
(since MAC keys invented by the main SSH-2 BPP are always shorter than
that).
2019-01-20 17:09:24 +00:00

514 lines
18 KiB
C

/*
* SHA-256 algorithm as described at
*
* http://csrc.nist.gov/cryptval/shs.html
*/
#include "ssh.h"
#include <assert.h>
/* ----------------------------------------------------------------------
* Core SHA256 algorithm: processes 16-word blocks into a message digest.
*/
#define ror(x,y) ( ((x) << (32-y)) | (((uint32_t)(x)) >> (y)) )
#define shr(x,y) ( (((uint32_t)(x)) >> (y)) )
#define Ch(x,y,z) ( ((x) & (y)) ^ (~(x) & (z)) )
#define Maj(x,y,z) ( ((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)) )
#define bigsigma0(x) ( ror((x),2) ^ ror((x),13) ^ ror((x),22) )
#define bigsigma1(x) ( ror((x),6) ^ ror((x),11) ^ ror((x),25) )
#define smallsigma0(x) ( ror((x),7) ^ ror((x),18) ^ shr((x),3) )
#define smallsigma1(x) ( ror((x),17) ^ ror((x),19) ^ shr((x),10) )
typedef struct SHA256_State {
uint32_t h[8];
unsigned char block[64];
int blkused;
uint64_t len;
void (*sha256)(struct SHA256_State * s, const unsigned char *p, int len);
BinarySink_IMPLEMENTATION;
} SHA256_State;
static void SHA256_sw(SHA256_State *s, const unsigned char *q, int len);
static void SHA256_ni(SHA256_State *s, const unsigned char *q, int len);
void SHA256_Core_Init(SHA256_State *s) {
s->h[0] = 0x6a09e667;
s->h[1] = 0xbb67ae85;
s->h[2] = 0x3c6ef372;
s->h[3] = 0xa54ff53a;
s->h[4] = 0x510e527f;
s->h[5] = 0x9b05688c;
s->h[6] = 0x1f83d9ab;
s->h[7] = 0x5be0cd19;
}
void SHA256_Block(SHA256_State *s, uint32_t *block) {
uint32_t w[80];
uint32_t a,b,c,d,e,f,g,h;
static const int k[] = {
0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
};
int t;
for (t = 0; t < 16; t++)
w[t] = block[t];
for (t = 16; t < 64; t++)
w[t] = smallsigma1(w[t-2]) + w[t-7] + smallsigma0(w[t-15]) + w[t-16];
a = s->h[0]; b = s->h[1]; c = s->h[2]; d = s->h[3];
e = s->h[4]; f = s->h[5]; g = s->h[6]; h = s->h[7];
for (t = 0; t < 64; t+=8) {
uint32_t t1, t2;
#define ROUND(j,a,b,c,d,e,f,g,h) \
t1 = h + bigsigma1(e) + Ch(e,f,g) + k[j] + w[j]; \
t2 = bigsigma0(a) + Maj(a,b,c); \
d = d + t1; h = t1 + t2;
ROUND(t+0, a,b,c,d,e,f,g,h);
ROUND(t+1, h,a,b,c,d,e,f,g);
ROUND(t+2, g,h,a,b,c,d,e,f);
ROUND(t+3, f,g,h,a,b,c,d,e);
ROUND(t+4, e,f,g,h,a,b,c,d);
ROUND(t+5, d,e,f,g,h,a,b,c);
ROUND(t+6, c,d,e,f,g,h,a,b);
ROUND(t+7, b,c,d,e,f,g,h,a);
}
s->h[0] += a; s->h[1] += b; s->h[2] += c; s->h[3] += d;
s->h[4] += e; s->h[5] += f; s->h[6] += g; s->h[7] += h;
}
/* ----------------------------------------------------------------------
* Outer SHA256 algorithm: take an arbitrary length byte string,
* convert it into 16-word blocks with the prescribed padding at
* the end, and pass those blocks to the core SHA256 algorithm.
*/
#define BLKSIZE 64
static void SHA256_BinarySink_write(BinarySink *bs,
const void *p, size_t len);
void SHA256_Init(SHA256_State *s) {
SHA256_Core_Init(s);
s->blkused = 0;
s->len = 0;
if (supports_sha_ni())
s->sha256 = &SHA256_ni;
else
s->sha256 = &SHA256_sw;
BinarySink_INIT(s, SHA256_BinarySink_write);
}
static void SHA256_BinarySink_write(BinarySink *bs,
const void *p, size_t len)
{
struct SHA256_State *s = BinarySink_DOWNCAST(bs, struct SHA256_State);
unsigned char *q = (unsigned char *)p;
/*
* Update the length field.
*/
s->len += len;
(*(s->sha256))(s, q, len);
}
static void SHA256_sw(SHA256_State *s, const unsigned char *q, int len) {
uint32_t wordblock[16];
int i;
if (s->blkused && s->blkused+len < BLKSIZE) {
/*
* Trivial case: just add to the block.
*/
memcpy(s->block + s->blkused, q, len);
s->blkused += len;
} else {
/*
* We must complete and process at least one block.
*/
while (s->blkused + len >= BLKSIZE) {
memcpy(s->block + s->blkused, q, BLKSIZE - s->blkused);
q += BLKSIZE - s->blkused;
len -= BLKSIZE - s->blkused;
/* Now process the block. Gather bytes big-endian into words */
for (i = 0; i < 16; i++) {
wordblock[i] =
( ((uint32_t)s->block[i*4+0]) << 24 ) |
( ((uint32_t)s->block[i*4+1]) << 16 ) |
( ((uint32_t)s->block[i*4+2]) << 8 ) |
( ((uint32_t)s->block[i*4+3]) << 0 );
}
SHA256_Block(s, wordblock);
s->blkused = 0;
}
memcpy(s->block, q, len);
s->blkused = len;
}
}
void SHA256_Final(SHA256_State *s, unsigned char *digest) {
int i;
int pad;
unsigned char c[64];
uint64_t len;
if (s->blkused >= 56)
pad = 56 + 64 - s->blkused;
else
pad = 56 - s->blkused;
len = (s->len << 3);
memset(c, 0, pad);
c[0] = 0x80;
put_data(s, &c, pad);
put_uint64(s, len);
for (i = 0; i < 8; i++) {
digest[i*4+0] = (s->h[i] >> 24) & 0xFF;
digest[i*4+1] = (s->h[i] >> 16) & 0xFF;
digest[i*4+2] = (s->h[i] >> 8) & 0xFF;
digest[i*4+3] = (s->h[i] >> 0) & 0xFF;
}
}
void SHA256_Simple(const void *p, int len, unsigned char *output) {
SHA256_State s;
SHA256_Init(&s);
put_data(&s, p, len);
SHA256_Final(&s, output);
smemclr(&s, sizeof(s));
}
/*
* Thin abstraction for things where hashes are pluggable.
*/
struct sha256_hash {
SHA256_State state;
ssh_hash hash;
};
static ssh_hash *sha256_new(const ssh_hashalg *alg)
{
struct sha256_hash *h = snew(struct sha256_hash);
SHA256_Init(&h->state);
h->hash.vt = alg;
BinarySink_DELEGATE_INIT(&h->hash, &h->state);
return &h->hash;
}
static ssh_hash *sha256_copy(ssh_hash *hashold)
{
struct sha256_hash *hold, *hnew;
ssh_hash *hashnew = sha256_new(hashold->vt);
hold = container_of(hashold, struct sha256_hash, hash);
hnew = container_of(hashnew, struct sha256_hash, hash);
hnew->state = hold->state;
BinarySink_COPIED(&hnew->state);
return hashnew;
}
static void sha256_free(ssh_hash *hash)
{
struct sha256_hash *h = container_of(hash, struct sha256_hash, hash);
smemclr(h, sizeof(*h));
sfree(h);
}
static void sha256_final(ssh_hash *hash, unsigned char *output)
{
struct sha256_hash *h = container_of(hash, struct sha256_hash, hash);
SHA256_Final(&h->state, output);
sha256_free(hash);
}
const ssh_hashalg ssh_sha256 = {
sha256_new, sha256_copy, sha256_final, sha256_free, 32, "SHA-256"
};
#ifdef COMPILER_SUPPORTS_SHA_NI
#if defined _MSC_VER && defined _M_AMD64
# include <intrin.h>
#endif
/*
* Set target architecture for Clang and GCC
*/
#if !defined(__clang__) && defined(__GNUC__)
# pragma GCC target("sha")
# pragma GCC target("sse4.1")
#endif
#if defined(__clang__) || (defined(__GNUC__) && (__GNUC__ >= 5))
# define FUNC_ISA __attribute__ ((target("sse4.1,sha")))
#else
# define FUNC_ISA
#endif
#include <wmmintrin.h>
#include <smmintrin.h>
#include <immintrin.h>
#if defined(__clang__) || defined(__GNUC__)
#include <shaintrin.h>
#endif
/* SHA256 implementation using new instructions
The code is based on Jeffrey Walton's SHA256 implementation:
https://github.com/noloader/SHA-Intrinsics
*/
FUNC_ISA
static void SHA256_ni_(SHA256_State * s, const unsigned char *q, int len) {
if (s->blkused && s->blkused+len < BLKSIZE) {
/*
* Trivial case: just add to the block.
*/
memcpy(s->block + s->blkused, q, len);
s->blkused += len;
} else {
__m128i STATE0, STATE1;
__m128i MSG, TMP;
__m128i MSG0, MSG1, MSG2, MSG3;
__m128i ABEF_SAVE, CDGH_SAVE;
const __m128i MASK = _mm_set_epi64x(0x0c0d0e0f08090a0bULL, 0x0405060700010203ULL);
/* Load initial values */
TMP = _mm_loadu_si128((const __m128i*) &s->h[0]);
STATE1 = _mm_loadu_si128((const __m128i*) &s->h[4]);
TMP = _mm_shuffle_epi32(TMP, 0xB1); /* CDAB */
STATE1 = _mm_shuffle_epi32(STATE1, 0x1B); /* EFGH */
STATE0 = _mm_alignr_epi8(TMP, STATE1, 8); /* ABEF */
STATE1 = _mm_blend_epi16(STATE1, TMP, 0xF0); /* CDGH */
/*
* We must complete and process at least one block.
*/
while (s->blkused + len >= BLKSIZE) {
memcpy(s->block + s->blkused, q, BLKSIZE - s->blkused);
q += BLKSIZE - s->blkused;
len -= BLKSIZE - s->blkused;
/* Save current state */
ABEF_SAVE = STATE0;
CDGH_SAVE = STATE1;
/* Rounds 0-3 */
MSG = _mm_loadu_si128((const __m128i*) (s->block + 0));
MSG0 = _mm_shuffle_epi8(MSG, MASK);
MSG = _mm_add_epi32(MSG0, _mm_set_epi64x(0xE9B5DBA5B5C0FBCFULL, 0x71374491428A2F98ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
/* Rounds 4-7 */
MSG1 = _mm_loadu_si128((const __m128i*) (s->block + 16));
MSG1 = _mm_shuffle_epi8(MSG1, MASK);
MSG = _mm_add_epi32(MSG1, _mm_set_epi64x(0xAB1C5ED5923F82A4ULL, 0x59F111F13956C25BULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG0 = _mm_sha256msg1_epu32(MSG0, MSG1);
/* Rounds 8-11 */
MSG2 = _mm_loadu_si128((const __m128i*) (s->block + 32));
MSG2 = _mm_shuffle_epi8(MSG2, MASK);
MSG = _mm_add_epi32(MSG2, _mm_set_epi64x(0x550C7DC3243185BEULL, 0x12835B01D807AA98ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG1 = _mm_sha256msg1_epu32(MSG1, MSG2);
/* Rounds 12-15 */
MSG3 = _mm_loadu_si128((const __m128i*) (s->block + 48));
MSG3 = _mm_shuffle_epi8(MSG3, MASK);
MSG = _mm_add_epi32(MSG3, _mm_set_epi64x(0xC19BF1749BDC06A7ULL, 0x80DEB1FE72BE5D74ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG3, MSG2, 4);
MSG0 = _mm_add_epi32(MSG0, TMP);
MSG0 = _mm_sha256msg2_epu32(MSG0, MSG3);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG2 = _mm_sha256msg1_epu32(MSG2, MSG3);
/* Rounds 16-19 */
MSG = _mm_add_epi32(MSG0, _mm_set_epi64x(0x240CA1CC0FC19DC6ULL, 0xEFBE4786E49B69C1ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG0, MSG3, 4);
MSG1 = _mm_add_epi32(MSG1, TMP);
MSG1 = _mm_sha256msg2_epu32(MSG1, MSG0);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG3 = _mm_sha256msg1_epu32(MSG3, MSG0);
/* Rounds 20-23 */
MSG = _mm_add_epi32(MSG1, _mm_set_epi64x(0x76F988DA5CB0A9DCULL, 0x4A7484AA2DE92C6FULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG1, MSG0, 4);
MSG2 = _mm_add_epi32(MSG2, TMP);
MSG2 = _mm_sha256msg2_epu32(MSG2, MSG1);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG0 = _mm_sha256msg1_epu32(MSG0, MSG1);
/* Rounds 24-27 */
MSG = _mm_add_epi32(MSG2, _mm_set_epi64x(0xBF597FC7B00327C8ULL, 0xA831C66D983E5152ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG2, MSG1, 4);
MSG3 = _mm_add_epi32(MSG3, TMP);
MSG3 = _mm_sha256msg2_epu32(MSG3, MSG2);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG1 = _mm_sha256msg1_epu32(MSG1, MSG2);
/* Rounds 28-31 */
MSG = _mm_add_epi32(MSG3, _mm_set_epi64x(0x1429296706CA6351ULL, 0xD5A79147C6E00BF3ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG3, MSG2, 4);
MSG0 = _mm_add_epi32(MSG0, TMP);
MSG0 = _mm_sha256msg2_epu32(MSG0, MSG3);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG2 = _mm_sha256msg1_epu32(MSG2, MSG3);
/* Rounds 32-35 */
MSG = _mm_add_epi32(MSG0, _mm_set_epi64x(0x53380D134D2C6DFCULL, 0x2E1B213827B70A85ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG0, MSG3, 4);
MSG1 = _mm_add_epi32(MSG1, TMP);
MSG1 = _mm_sha256msg2_epu32(MSG1, MSG0);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG3 = _mm_sha256msg1_epu32(MSG3, MSG0);
/* Rounds 36-39 */
MSG = _mm_add_epi32(MSG1, _mm_set_epi64x(0x92722C8581C2C92EULL, 0x766A0ABB650A7354ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG1, MSG0, 4);
MSG2 = _mm_add_epi32(MSG2, TMP);
MSG2 = _mm_sha256msg2_epu32(MSG2, MSG1);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG0 = _mm_sha256msg1_epu32(MSG0, MSG1);
/* Rounds 40-43 */
MSG = _mm_add_epi32(MSG2, _mm_set_epi64x(0xC76C51A3C24B8B70ULL, 0xA81A664BA2BFE8A1ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG2, MSG1, 4);
MSG3 = _mm_add_epi32(MSG3, TMP);
MSG3 = _mm_sha256msg2_epu32(MSG3, MSG2);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG1 = _mm_sha256msg1_epu32(MSG1, MSG2);
/* Rounds 44-47 */
MSG = _mm_add_epi32(MSG3, _mm_set_epi64x(0x106AA070F40E3585ULL, 0xD6990624D192E819ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG3, MSG2, 4);
MSG0 = _mm_add_epi32(MSG0, TMP);
MSG0 = _mm_sha256msg2_epu32(MSG0, MSG3);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG2 = _mm_sha256msg1_epu32(MSG2, MSG3);
/* Rounds 48-51 */
MSG = _mm_add_epi32(MSG0, _mm_set_epi64x(0x34B0BCB52748774CULL, 0x1E376C0819A4C116ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG0, MSG3, 4);
MSG1 = _mm_add_epi32(MSG1, TMP);
MSG1 = _mm_sha256msg2_epu32(MSG1, MSG0);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
MSG3 = _mm_sha256msg1_epu32(MSG3, MSG0);
/* Rounds 52-55 */
MSG = _mm_add_epi32(MSG1, _mm_set_epi64x(0x682E6FF35B9CCA4FULL, 0x4ED8AA4A391C0CB3ULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG1, MSG0, 4);
MSG2 = _mm_add_epi32(MSG2, TMP);
MSG2 = _mm_sha256msg2_epu32(MSG2, MSG1);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
/* Rounds 56-59 */
MSG = _mm_add_epi32(MSG2, _mm_set_epi64x(0x8CC7020884C87814ULL, 0x78A5636F748F82EEULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
TMP = _mm_alignr_epi8(MSG2, MSG1, 4);
MSG3 = _mm_add_epi32(MSG3, TMP);
MSG3 = _mm_sha256msg2_epu32(MSG3, MSG2);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
/* Rounds 60-63 */
MSG = _mm_add_epi32(MSG3, _mm_set_epi64x(0xC67178F2BEF9A3F7ULL, 0xA4506CEB90BEFFFAULL));
STATE1 = _mm_sha256rnds2_epu32(STATE1, STATE0, MSG);
MSG = _mm_shuffle_epi32(MSG, 0x0E);
STATE0 = _mm_sha256rnds2_epu32(STATE0, STATE1, MSG);
/* Combine state */
STATE0 = _mm_add_epi32(STATE0, ABEF_SAVE);
STATE1 = _mm_add_epi32(STATE1, CDGH_SAVE);
s->blkused = 0;
}
TMP = _mm_shuffle_epi32(STATE0, 0x1B); /* FEBA */
STATE1 = _mm_shuffle_epi32(STATE1, 0xB1); /* DCHG */
STATE0 = _mm_blend_epi16(TMP, STATE1, 0xF0); /* DCBA */
STATE1 = _mm_alignr_epi8(STATE1, TMP, 8); /* ABEF */
/* Save state */
_mm_storeu_si128((__m128i*) &s->h[0], STATE0);
_mm_storeu_si128((__m128i*) &s->h[4], STATE1);
memcpy(s->block, q, len);
s->blkused = len;
}
}
/*
* Workaround LLVM bug https://bugs.llvm.org/show_bug.cgi?id=34980
*/
static void SHA256_ni(SHA256_State * s, const unsigned char *q, int len)
{
SHA256_ni_(s, q, len);
}
#else /* COMPILER_SUPPORTS_AES_NI */
static void SHA256_ni(SHA256_State * s, const unsigned char *q, int len)
{
unreachable("SHA256_ni not compiled in");
}
#endif /* COMPILER_SUPPORTS_AES_NI */