blake2s: simplify final function

Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

3 files changed, 19 insertions, 40 deletions

diff --git a/src/compat/compat.h b/src/compat/compat.h
index 9e92236..c182234 100644
--- a/src/compat/compat.h
+++ b/src/compat/compat.h
@@ -688,6 +688,16 @@ static inline void *skb_put_data(struct sk_buff *skb, const void *data, unsigned
 #endif
 #endif
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 17, 0)
+static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
+{
+	while (words--) {
+		__cpu_to_le32s(buf);
+		buf++;
+	}
+}
+#endif
+
 /* https://lkml.kernel.org/r/20170624021727.17835-1-Jason@zx2c4.com */
 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 #include <linux/ip.h>
diff --git a/src/crypto/include/zinc/blake2s.h b/src/crypto/include/zinc/blake2s.h
index 9512815..7a4382c 100644
--- a/src/crypto/include/zinc/blake2s.h
+++ b/src/crypto/include/zinc/blake2s.h
@@ -29,44 +29,7 @@ void blake2s_init(struct blake2s_state *state, const size_t outlen);
 void blake2s_init_key(struct blake2s_state *state, const size_t outlen,
 		      const void *key, const size_t keylen);
 void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen);
-void __blake2s_final(struct blake2s_state *state);
-static inline void blake2s_final(struct blake2s_state *state, u8 *out,
-				 const size_t outlen)
-{
-	int i;
-
-#ifdef DEBUG
-	BUG_ON(!out || !outlen || outlen > BLAKE2S_OUTBYTES);
-#endif
-	__blake2s_final(state);
-
-	if (__builtin_constant_p(outlen) && !(outlen % sizeof(u32))) {
-		if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) ||
-		    IS_ALIGNED((unsigned long)out, __alignof__(u32))) {
-			__le32 *outwords = (__le32 *)out;
-
-			for (i = 0; i < outlen / sizeof(u32); ++i)
-				outwords[i] = cpu_to_le32(state->h[i]);
-		} else {
-			__le32 buffer[BLAKE2S_OUTBYTES];
-
-			for (i = 0; i < outlen / sizeof(u32); ++i)
-				buffer[i] = cpu_to_le32(state->h[i]);
-			memcpy(out, buffer, outlen);
-			memzero_explicit(buffer, sizeof(buffer));
-		}
-	} else {
-		u8 buffer[BLAKE2S_OUTBYTES] __aligned(__alignof__(u32));
-		__le32 *outwords = (__le32 *)buffer;
-
-		for (i = 0; i < 8; ++i)
-			outwords[i] = cpu_to_le32(state->h[i]);
-		memcpy(out, buffer, outlen);
-		memzero_explicit(buffer, sizeof(buffer));
-	}
-
-	memzero_explicit(state, sizeof(*state));
-}
+void blake2s_final(struct blake2s_state *state, u8 *out, const size_t outlen);
 
 static inline void blake2s(u8 *out, const u8 *in, const u8 *key,
 			   const size_t outlen, const size_t inlen,
diff --git a/src/crypto/zinc/blake2s/blake2s.c b/src/crypto/zinc/blake2s/blake2s.c
index 69b2b4e..29382da 100644
--- a/src/crypto/zinc/blake2s/blake2s.c
+++ b/src/crypto/zinc/blake2s/blake2s.c
@@ -230,14 +230,20 @@ void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen)
 }
 EXPORT_SYMBOL(blake2s_update);
 
-void __blake2s_final(struct blake2s_state *state)
+void blake2s_final(struct blake2s_state *state, u8 *out, const size_t outlen)
 {
+#ifdef DEBUG
+	BUG_ON(!out || !outlen || outlen > BLAKE2S_OUTBYTES);
+#endif
 	blake2s_set_lastblock(state);
 	memset(state->buf + state->buflen, 0,
 	       BLAKE2S_BLOCKBYTES - state->buflen); /* Padding */
 	blake2s_compress(state, state->buf, 1, state->buflen);
+	cpu_to_le32_array(state->h, ARRAY_SIZE(state->h));
+	memcpy(out, state->h, outlen);
+	memzero_explicit(state, sizeof(*state));
 }
-EXPORT_SYMBOL(__blake2s_final);
+EXPORT_SYMBOL(blake2s_final);
 
 void blake2s_hmac(u8 *out, const u8 *in, const u8 *key, const size_t outlen,
 		  const size_t inlen, const size_t keylen)