lib: Add xxhash support

This adds the xxhash support from Linux. Files are almost identical to
those added to Linux in commit 5d240522 ("lib: Add xxhash module") (they
haven't been touched since in Linux). The only difference is to add some
includes to be compatible with U-Boot. Also SPDX lincese tags were
added.

Signed-off-by: Marek Behún <marek.behun@nic.cz>

3 files changed, 471 insertions, 0 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 38012506d2..1ed69fafc7 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -327,6 +327,9 @@ config MD5
 config CRC32C
 	bool
 
+config XXHASH
+	bool
+
 endmenu
 
 menu "Compression Support"
diff --git a/lib/Makefile b/lib/Makefile
index 47829bfed5..6a52543530 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += smbios.o
 obj-$(CONFIG_IMAGE_SPARSE) += image-sparse.o
 obj-y += ldiv.o
 obj-$(CONFIG_MD5) += md5.o
+obj-$(CONFIG_XXHASH) += xxhash.o
 obj-y += net_utils.o
 obj-$(CONFIG_PHYSMEM) += physmem.o
 obj-y += rc4.o
diff --git a/lib/xxhash.c b/lib/xxhash.c
new file mode 100644
index 0000000000..2fb4dc6d02
--- /dev/null
+++ b/lib/xxhash.c
@@ -0,0 +1,467 @@
+// SPDX-License-Identifier: (GPL-2.0 or BSD-2-Clause)
+/*
+ * xxHash - Extremely Fast Hash algorithm
+ * Copyright (C) 2012-2016, Yann Collet.
+ *
+ * You can contact the author at:
+ * - xxHash homepage: http://cyan4973.github.io/xxHash/
+ * - xxHash source repository: https://github.com/Cyan4973/xxHash
+ */
+
+#include <asm/unaligned.h>
+#include <linux/errno.h>
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/compat.h>
+#include <linux/string.h>
+#include <linux/xxhash.h>
+
+/*-*************************************
+ * Macros
+ **************************************/
+#define xxh_rotl32(x, r) ((x << r) | (x >> (32 - r)))
+#define xxh_rotl64(x, r) ((x << r) | (x >> (64 - r)))
+
+#ifdef __LITTLE_ENDIAN
+# define XXH_CPU_LITTLE_ENDIAN 1
+#else
+# define XXH_CPU_LITTLE_ENDIAN 0
+#endif
+
+/*-*************************************
+ * Constants
+ **************************************/
+static const uint32_t PRIME32_1 = 2654435761U;
+static const uint32_t PRIME32_2 = 2246822519U;
+static const uint32_t PRIME32_3 = 3266489917U;
+static const uint32_t PRIME32_4 =  668265263U;
+static const uint32_t PRIME32_5 =  374761393U;
+
+static const uint64_t PRIME64_1 = 11400714785074694791ULL;
+static const uint64_t PRIME64_2 = 14029467366897019727ULL;
+static const uint64_t PRIME64_3 =  1609587929392839161ULL;
+static const uint64_t PRIME64_4 =  9650029242287828579ULL;
+static const uint64_t PRIME64_5 =  2870177450012600261ULL;
+
+/*-**************************
+ *  Utils
+ ***************************/
+void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src)
+{
+	memcpy(dst, src, sizeof(*dst));
+}
+EXPORT_SYMBOL(xxh32_copy_state);
+
+void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src)
+{
+	memcpy(dst, src, sizeof(*dst));
+}
+EXPORT_SYMBOL(xxh64_copy_state);
+
+/*-***************************
+ * Simple Hash Functions
+ ****************************/
+static uint32_t xxh32_round(uint32_t seed, const uint32_t input)
+{
+	seed += input * PRIME32_2;
+	seed = xxh_rotl32(seed, 13);
+	seed *= PRIME32_1;
+	return seed;
+}
+
+uint32_t xxh32(const void *input, const size_t len, const uint32_t seed)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *b_end = p + len;
+	uint32_t h32;
+
+	if (len >= 16) {
+		const uint8_t *const limit = b_end - 16;
+		uint32_t v1 = seed + PRIME32_1 + PRIME32_2;
+		uint32_t v2 = seed + PRIME32_2;
+		uint32_t v3 = seed + 0;
+		uint32_t v4 = seed - PRIME32_1;
+
+		do {
+			v1 = xxh32_round(v1, get_unaligned_le32(p));
+			p += 4;
+			v2 = xxh32_round(v2, get_unaligned_le32(p));
+			p += 4;
+			v3 = xxh32_round(v3, get_unaligned_le32(p));
+			p += 4;
+			v4 = xxh32_round(v4, get_unaligned_le32(p));
+			p += 4;
+		} while (p <= limit);
+
+		h32 = xxh_rotl32(v1, 1) + xxh_rotl32(v2, 7) +
+			xxh_rotl32(v3, 12) + xxh_rotl32(v4, 18);
+	} else {
+		h32 = seed + PRIME32_5;
+	}
+
+	h32 += (uint32_t)len;
+
+	while (p + 4 <= b_end) {
+		h32 += get_unaligned_le32(p) * PRIME32_3;
+		h32 = xxh_rotl32(h32, 17) * PRIME32_4;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h32 += (*p) * PRIME32_5;
+		h32 = xxh_rotl32(h32, 11) * PRIME32_1;
+		p++;
+	}
+
+	h32 ^= h32 >> 15;
+	h32 *= PRIME32_2;
+	h32 ^= h32 >> 13;
+	h32 *= PRIME32_3;
+	h32 ^= h32 >> 16;
+
+	return h32;
+}
+EXPORT_SYMBOL(xxh32);
+
+static uint64_t xxh64_round(uint64_t acc, const uint64_t input)
+{
+	acc += input * PRIME64_2;
+	acc = xxh_rotl64(acc, 31);
+	acc *= PRIME64_1;
+	return acc;
+}
+
+static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val)
+{
+	val = xxh64_round(0, val);
+	acc ^= val;
+	acc = acc * PRIME64_1 + PRIME64_4;
+	return acc;
+}
+
+uint64_t xxh64(const void *input, const size_t len, const uint64_t seed)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *const b_end = p + len;
+	uint64_t h64;
+
+	if (len >= 32) {
+		const uint8_t *const limit = b_end - 32;
+		uint64_t v1 = seed + PRIME64_1 + PRIME64_2;
+		uint64_t v2 = seed + PRIME64_2;
+		uint64_t v3 = seed + 0;
+		uint64_t v4 = seed - PRIME64_1;
+
+		do {
+			v1 = xxh64_round(v1, get_unaligned_le64(p));
+			p += 8;
+			v2 = xxh64_round(v2, get_unaligned_le64(p));
+			p += 8;
+			v3 = xxh64_round(v3, get_unaligned_le64(p));
+			p += 8;
+			v4 = xxh64_round(v4, get_unaligned_le64(p));
+			p += 8;
+		} while (p <= limit);
+
+		h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) +
+			xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18);
+		h64 = xxh64_merge_round(h64, v1);
+		h64 = xxh64_merge_round(h64, v2);
+		h64 = xxh64_merge_round(h64, v3);
+		h64 = xxh64_merge_round(h64, v4);
+
+	} else {
+		h64  = seed + PRIME64_5;
+	}
+
+	h64 += (uint64_t)len;
+
+	while (p + 8 <= b_end) {
+		const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p));
+
+		h64 ^= k1;
+		h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4;
+		p += 8;
+	}
+
+	if (p + 4 <= b_end) {
+		h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1;
+		h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h64 ^= (*p) * PRIME64_5;
+		h64 = xxh_rotl64(h64, 11) * PRIME64_1;
+		p++;
+	}
+
+	h64 ^= h64 >> 33;
+	h64 *= PRIME64_2;
+	h64 ^= h64 >> 29;
+	h64 *= PRIME64_3;
+	h64 ^= h64 >> 32;
+
+	return h64;
+}
+EXPORT_SYMBOL(xxh64);
+
+/*-**************************************************
+ * Advanced Hash Functions
+ ***************************************************/
+void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed)
+{
+	/* use a local state for memcpy() to avoid strict-aliasing warnings */
+	struct xxh32_state state;
+
+	memset(&state, 0, sizeof(state));
+	state.v1 = seed + PRIME32_1 + PRIME32_2;
+	state.v2 = seed + PRIME32_2;
+	state.v3 = seed + 0;
+	state.v4 = seed - PRIME32_1;
+	memcpy(statePtr, &state, sizeof(state));
+}
+EXPORT_SYMBOL(xxh32_reset);
+
+void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed)
+{
+	/* use a local state for memcpy() to avoid strict-aliasing warnings */
+	struct xxh64_state state;
+
+	memset(&state, 0, sizeof(state));
+	state.v1 = seed + PRIME64_1 + PRIME64_2;
+	state.v2 = seed + PRIME64_2;
+	state.v3 = seed + 0;
+	state.v4 = seed - PRIME64_1;
+	memcpy(statePtr, &state, sizeof(state));
+}
+EXPORT_SYMBOL(xxh64_reset);
+
+int xxh32_update(struct xxh32_state *state, const void *input, const size_t len)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *const b_end = p + len;
+
+	if (input == NULL)
+		return -EINVAL;
+
+	state->total_len_32 += (uint32_t)len;
+	state->large_len |= (len >= 16) | (state->total_len_32 >= 16);
+
+	if (state->memsize + len < 16) { /* fill in tmp buffer */
+		memcpy((uint8_t *)(state->mem32) + state->memsize, input, len);
+		state->memsize += (uint32_t)len;
+		return 0;
+	}
+
+	if (state->memsize) { /* some data left from previous update */
+		const uint32_t *p32 = state->mem32;
+
+		memcpy((uint8_t *)(state->mem32) + state->memsize, input,
+			16 - state->memsize);
+
+		state->v1 = xxh32_round(state->v1, get_unaligned_le32(p32));
+		p32++;
+		state->v2 = xxh32_round(state->v2, get_unaligned_le32(p32));
+		p32++;
+		state->v3 = xxh32_round(state->v3, get_unaligned_le32(p32));
+		p32++;
+		state->v4 = xxh32_round(state->v4, get_unaligned_le32(p32));
+		p32++;
+
+		p += 16-state->memsize;
+		state->memsize = 0;
+	}
+
+	if (p <= b_end - 16) {
+		const uint8_t *const limit = b_end - 16;
+		uint32_t v1 = state->v1;
+		uint32_t v2 = state->v2;
+		uint32_t v3 = state->v3;
+		uint32_t v4 = state->v4;
+
+		do {
+			v1 = xxh32_round(v1, get_unaligned_le32(p));
+			p += 4;
+			v2 = xxh32_round(v2, get_unaligned_le32(p));
+			p += 4;
+			v3 = xxh32_round(v3, get_unaligned_le32(p));
+			p += 4;
+			v4 = xxh32_round(v4, get_unaligned_le32(p));
+			p += 4;
+		} while (p <= limit);
+
+		state->v1 = v1;
+		state->v2 = v2;
+		state->v3 = v3;
+		state->v4 = v4;
+	}
+
+	if (p < b_end) {
+		memcpy(state->mem32, p, (size_t)(b_end-p));
+		state->memsize = (uint32_t)(b_end-p);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(xxh32_update);
+
+uint32_t xxh32_digest(const struct xxh32_state *state)
+{
+	const uint8_t *p = (const uint8_t *)state->mem32;
+	const uint8_t *const b_end = (const uint8_t *)(state->mem32) +
+		state->memsize;
+	uint32_t h32;
+
+	if (state->large_len) {
+		h32 = xxh_rotl32(state->v1, 1) + xxh_rotl32(state->v2, 7) +
+			xxh_rotl32(state->v3, 12) + xxh_rotl32(state->v4, 18);
+	} else {
+		h32 = state->v3 /* == seed */ + PRIME32_5;
+	}
+
+	h32 += state->total_len_32;
+
+	while (p + 4 <= b_end) {
+		h32 += get_unaligned_le32(p) * PRIME32_3;
+		h32 = xxh_rotl32(h32, 17) * PRIME32_4;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h32 += (*p) * PRIME32_5;
+		h32 = xxh_rotl32(h32, 11) * PRIME32_1;
+		p++;
+	}
+
+	h32 ^= h32 >> 15;
+	h32 *= PRIME32_2;
+	h32 ^= h32 >> 13;
+	h32 *= PRIME32_3;
+	h32 ^= h32 >> 16;
+
+	return h32;
+}
+EXPORT_SYMBOL(xxh32_digest);
+
+int xxh64_update(struct xxh64_state *state, const void *input, const size_t len)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *const b_end = p + len;
+
+	if (input == NULL)
+		return -EINVAL;
+
+	state->total_len += len;
+
+	if (state->memsize + len < 32) { /* fill in tmp buffer */
+		memcpy(((uint8_t *)state->mem64) + state->memsize, input, len);
+		state->memsize += (uint32_t)len;
+		return 0;
+	}
+
+	if (state->memsize) { /* tmp buffer is full */
+		uint64_t *p64 = state->mem64;
+
+		memcpy(((uint8_t *)p64) + state->memsize, input,
+			32 - state->memsize);
+
+		state->v1 = xxh64_round(state->v1, get_unaligned_le64(p64));
+		p64++;
+		state->v2 = xxh64_round(state->v2, get_unaligned_le64(p64));
+		p64++;
+		state->v3 = xxh64_round(state->v3, get_unaligned_le64(p64));
+		p64++;
+		state->v4 = xxh64_round(state->v4, get_unaligned_le64(p64));
+
+		p += 32 - state->memsize;
+		state->memsize = 0;
+	}
+
+	if (p + 32 <= b_end) {
+		const uint8_t *const limit = b_end - 32;
+		uint64_t v1 = state->v1;
+		uint64_t v2 = state->v2;
+		uint64_t v3 = state->v3;
+		uint64_t v4 = state->v4;
+
+		do {
+			v1 = xxh64_round(v1, get_unaligned_le64(p));
+			p += 8;
+			v2 = xxh64_round(v2, get_unaligned_le64(p));
+			p += 8;
+			v3 = xxh64_round(v3, get_unaligned_le64(p));
+			p += 8;
+			v4 = xxh64_round(v4, get_unaligned_le64(p));
+			p += 8;
+		} while (p <= limit);
+
+		state->v1 = v1;
+		state->v2 = v2;
+		state->v3 = v3;
+		state->v4 = v4;
+	}
+
+	if (p < b_end) {
+		memcpy(state->mem64, p, (size_t)(b_end-p));
+		state->memsize = (uint32_t)(b_end - p);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(xxh64_update);
+
+uint64_t xxh64_digest(const struct xxh64_state *state)
+{
+	const uint8_t *p = (const uint8_t *)state->mem64;
+	const uint8_t *const b_end = (const uint8_t *)state->mem64 +
+		state->memsize;
+	uint64_t h64;
+
+	if (state->total_len >= 32) {
+		const uint64_t v1 = state->v1;
+		const uint64_t v2 = state->v2;
+		const uint64_t v3 = state->v3;
+		const uint64_t v4 = state->v4;
+
+		h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) +
+			xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18);
+		h64 = xxh64_merge_round(h64, v1);
+		h64 = xxh64_merge_round(h64, v2);
+		h64 = xxh64_merge_round(h64, v3);
+		h64 = xxh64_merge_round(h64, v4);
+	} else {
+		h64  = state->v3 + PRIME64_5;
+	}
+
+	h64 += (uint64_t)state->total_len;
+
+	while (p + 8 <= b_end) {
+		const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p));
+
+		h64 ^= k1;
+		h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4;
+		p += 8;
+	}
+
+	if (p + 4 <= b_end) {
+		h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1;
+		h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h64 ^= (*p) * PRIME64_5;
+		h64 = xxh_rotl64(h64, 11) * PRIME64_1;
+		p++;
+	}
+
+	h64 ^= h64 >> 33;
+	h64 *= PRIME64_2;
+	h64 ^= h64 >> 29;
+	h64 *= PRIME64_3;
+	h64 ^= h64 >> 32;
+
+	return h64;
+}
+EXPORT_SYMBOL(xxh64_digest);