1 files changed, 101 insertions, 8 deletions

diff --git a/include/crypto/internal/blake2s.h b/include/crypto/internal/blake2s.h
index 6e376ae6b6b5..8e50d487500f 100644
--- a/include/crypto/internal/blake2s.h
+++ b/include/crypto/internal/blake2s.h
@@ -1,14 +1,15 @@
 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/*
+ * Helper functions for BLAKE2s implementations.
+ * Keep this in sync with the corresponding BLAKE2b header.
+ */
 
-#ifndef BLAKE2S_INTERNAL_H
-#define BLAKE2S_INTERNAL_H
+#ifndef _CRYPTO_INTERNAL_BLAKE2S_H
+#define _CRYPTO_INTERNAL_BLAKE2S_H
 
 #include <crypto/blake2s.h>
-
-struct blake2s_tfm_ctx {
-	u8 key[BLAKE2S_KEY_SIZE];
-	unsigned int keylen;
-};
+#include <crypto/internal/hash.h>
+#include <linux/string.h>
 
 void blake2s_compress_generic(struct blake2s_state *state,const u8 *block,
 			      size_t nblocks, const u32 inc);
@@ -23,4 +24,96 @@ static inline void blake2s_set_lastblock(struct blake2s_state *state)
 	state->f[0] = -1;
 }
 
-#endif /* BLAKE2S_INTERNAL_H */
+typedef void (*blake2s_compress_t)(struct blake2s_state *state,
+				   const u8 *block, size_t nblocks, u32 inc);
+
+/* Helper functions for BLAKE2s shared by the library and shash APIs */
+
+static inline void __blake2s_update(struct blake2s_state *state,
+				    const u8 *in, size_t inlen,
+				    blake2s_compress_t compress)
+{
+	const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen;
+
+	if (unlikely(!inlen))
+		return;
+	if (inlen > fill) {
+		memcpy(state->buf + state->buflen, in, fill);
+		(*compress)(state, state->buf, 1, BLAKE2S_BLOCK_SIZE);
+		state->buflen = 0;
+		in += fill;
+		inlen -= fill;
+	}
+	if (inlen > BLAKE2S_BLOCK_SIZE) {
+		const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
+		/* Hash one less (full) block than strictly possible */
+		(*compress)(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
+		in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
+		inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
+	}
+	memcpy(state->buf + state->buflen, in, inlen);
+	state->buflen += inlen;
+}
+
+static inline void __blake2s_final(struct blake2s_state *state, u8 *out,
+				   blake2s_compress_t compress)
+{
+	blake2s_set_lastblock(state);
+	memset(state->buf + state->buflen, 0,
+	       BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */
+	(*compress)(state, state->buf, 1, state->buflen);
+	cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
+	memcpy(out, state->h, state->outlen);
+}
+
+/* Helper functions for shash implementations of BLAKE2s */
+
+struct blake2s_tfm_ctx {
+	u8 key[BLAKE2S_KEY_SIZE];
+	unsigned int keylen;
+};
+
+static inline int crypto_blake2s_setkey(struct crypto_shash *tfm,
+					const u8 *key, unsigned int keylen)
+{
+	struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm);
+
+	if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE)
+		return -EINVAL;
+
+	memcpy(tctx->key, key, keylen);
+	tctx->keylen = keylen;
+
+	return 0;
+}
+
+static inline int crypto_blake2s_init(struct shash_desc *desc)
+{
+	const struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
+	struct blake2s_state *state = shash_desc_ctx(desc);
+	unsigned int outlen = crypto_shash_digestsize(desc->tfm);
+
+	__blake2s_init(state, outlen, tctx->key, tctx->keylen);
+	return 0;
+}
+
+static inline int crypto_blake2s_update(struct shash_desc *desc,
+					const u8 *in, unsigned int inlen,
+					blake2s_compress_t compress)
+{
+	struct blake2s_state *state = shash_desc_ctx(desc);
+
+	__blake2s_update(state, in, inlen, compress);
+	return 0;
+}
+
+static inline int crypto_blake2s_final(struct shash_desc *desc, u8 *out,
+				       blake2s_compress_t compress)
+{
+	struct blake2s_state *state = shash_desc_ctx(desc);
+
+	__blake2s_final(state, out, compress);
+	return 0;
+}
+
+#endif /* _CRYPTO_INTERNAL_BLAKE2S_H */