static int sha256_final(struct shash_desc *desc, u8 *out)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
__be32 *dst = (__be32 *)out;
__be64 bits;
unsigned int index, pad_len;
int i;
static const u8 padding[64] = { 0x80, };
/* Save number of bits */
bits = cpu_to_be64(sctx->count << 3);
/* Pad out to 56 mod 64. */
index = sctx->count & 0x3f;
pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
crypto_sha256_update(desc, padding, pad_len);
/* Append length (before padding) */
crypto_sha256_update(desc, (const u8 *)&bits, sizeof(bits));
/* Store state in digest */
for (i = 0; i < 8; i++)
dst[i] = cpu_to_be32(sctx->state[i]);
/* Zeroize sensitive information. */
memset(sctx, 0, sizeof(*sctx));
return 0;
}
static int sha256_ssse3_update(struct shash_desc *desc, const u8 *data,
unsigned int len)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
int res;
/* Handle the fast case right here */
if (partial + len < SHA256_BLOCK_SIZE) {
sctx->count += len;
memcpy(sctx->buf + partial, data, len);
return 0;
}
if (!irq_fpu_usable()) {
res = crypto_sha256_update(desc, data, len);
} else {
kernel_fpu_begin();
res = __sha256_ssse3_update(desc, data, len, partial);
kernel_fpu_end();
}
return res;
}
/* Add padding and return the message digest. */
static int sha256_ssse3_final(struct shash_desc *desc, u8 *out)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
unsigned int i, index, padlen;
__be32 *dst = (__be32 *)out;
__be64 bits;
static const u8 padding[SHA256_BLOCK_SIZE] = { 0x80, };
bits = cpu_to_be64(sctx->count << 3);
/* Pad out to 56 mod 64 and append length */
index = sctx->count % SHA256_BLOCK_SIZE;
padlen = (index < 56) ? (56 - index) : ((SHA256_BLOCK_SIZE+56)-index);
if (!irq_fpu_usable()) {
crypto_sha256_update(desc, padding, padlen);
crypto_sha256_update(desc, (const u8 *)&bits, sizeof(bits));
} else {
kernel_fpu_begin();
/* We need to fill a whole block for __sha256_ssse3_update() */
if (padlen <= 56) {
sctx->count += padlen;
memcpy(sctx->buf + index, padding, padlen);
} else {
__sha256_ssse3_update(desc, padding, padlen, index);
}
__sha256_ssse3_update(desc, (const u8 *)&bits,
sizeof(bits), 56);
kernel_fpu_end();
}
/* Store state in digest */
for (i = 0; i < 8; i++)
dst[i] = cpu_to_be32(sctx->state[i]);
/* Wipe context */
memset(sctx, 0, sizeof(*sctx));
return 0;
}
static int sha256_update(struct shash_desc *desc, const u8 *data,
unsigned int len, sha256_transform_fn *sha256_xform)
{
struct sha256_state *sctx = shash_desc_ctx(desc);
if (!irq_fpu_usable() ||
(sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
return crypto_sha256_update(desc, data, len);
/* make sure casting to sha256_block_fn() is safe */
BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0);
kernel_fpu_begin();
sha256_base_do_update(desc, data, len,
(sha256_block_fn *)sha256_xform);
kernel_fpu_end();
return 0;
}
