--- /dev/null
+/*
+ * Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <openssl/evp.h>
+#include <openssl/objects.h>
+#include "internal/evp_int.h"
+#include "evp_locl.h"
+
+size_t SHA3_absorb(uint64_t A[5][5], const unsigned char *inp, size_t len,
+ size_t r);
+void SHA3_squeeze(uint64_t A[5][5], unsigned char *out, size_t len, size_t r);
+
+#define KECCAK1600_WIDTH 1600
+
+typedef struct {
+ uint64_t A[5][5];
+ size_t block_size; /* cached ctx->digest->block_size */
+ size_t md_size; /* output length, variable in XOF */
+ size_t num; /* used bytes in below buffer */
+ unsigned char buf[KECCAK1600_WIDTH / 8 - 32];
+ unsigned char pad;
+} KECCAK1600_CTX;
+
+static int init(EVP_MD_CTX *evp_ctx, unsigned char pad)
+{
+ KECCAK1600_CTX *ctx = evp_ctx->md_data;
+ size_t bsz = evp_ctx->digest->block_size;
+
+ if (bsz <= sizeof(ctx->buf)) {
+ memset(ctx->A, 0, sizeof(ctx->A));
+
+ ctx->num = 0;
+ ctx->block_size = bsz;
+ ctx->md_size = evp_ctx->digest->md_size;
+ ctx->pad = pad;
+
+ return 1;
+ }
+
+ return 0;
+}
+
+static int sha3_init(EVP_MD_CTX *evp_ctx)
+{
+ return init(evp_ctx, '\x06');
+}
+
+static int shake_init(EVP_MD_CTX *evp_ctx)
+{
+ return init(evp_ctx, '\x1f');
+}
+
+static int sha3_update(EVP_MD_CTX *evp_ctx, const void *_inp, size_t len)
+{
+ KECCAK1600_CTX *ctx = evp_ctx->md_data;
+ const unsigned char *inp = _inp;
+ size_t bsz = ctx->block_size;
+ size_t num, rem;
+
+ if ((num = ctx->num) != 0) { /* process intermediate buffer? */
+ rem = bsz - num;
+
+ if (len < rem) {
+ memcpy(ctx->buf + num, inp, len);
+ ctx->num += len;
+ return 1;
+ }
+ /*
+ * We have enough data to fill or overflow the intermediate
+ * buffer. So we append |rem| bytes and process the block,
+ * leaving the rest for later processing...
+ */
+ memcpy(ctx->buf + num, inp, rem);
+ inp += rem, len -= rem;
+ (void)SHA3_absorb(ctx->A, ctx->buf, bsz, bsz);
+ ctx->num = 0;
+ /* ctx->buf is processed, ctx->num is guaranteed to be zero */
+ }
+
+ if (len >= bsz)
+ rem = SHA3_absorb(ctx->A, inp, len, bsz);
+ else
+ rem = len;
+
+ if (rem) {
+ memcpy(ctx->buf, inp + len - rem, rem);
+ ctx->num = rem;
+ }
+
+ return 1;
+}
+
+static int sha3_final(EVP_MD_CTX *evp_ctx, unsigned char *md)
+{
+ KECCAK1600_CTX *ctx = evp_ctx->md_data;
+ size_t bsz = ctx->block_size;
+ size_t num = ctx->num;
+
+ /*
+ * Pad the data with 10*1. Note that |num| can be |bsz - 1|
+ * in which case both byte operations below are performed on
+ * same byte...
+ */
+ memset(ctx->buf + num, 0, bsz - num);
+ ctx->buf[num] = ctx->pad;
+ ctx->buf[bsz - 1] |= 0x80;
+
+ (void)SHA3_absorb(ctx->A, ctx->buf, bsz, bsz);
+
+ SHA3_squeeze(ctx->A, md, ctx->md_size, bsz);
+
+ return 1;
+}
+
+#define EVP_MD_SHA3(bitlen) \
+const EVP_MD *EVP_sha3_##bitlen(void) \
+{ \
+ static const EVP_MD sha3_##bitlen##_md = { \
+ NID_sha3_##bitlen, \
+ 0, \
+ bitlen / 8, \
+ 0, \
+ sha3_init, \
+ sha3_update, \
+ sha3_final, \
+ NULL, \
+ NULL, \
+ (KECCAK1600_WIDTH - bitlen * 2) / 8, \
+ sizeof(KECCAK1600_CTX), \
+ }; \
+ return &sha3_##bitlen##_md; \
+}
+
+EVP_MD_SHA3(224)
+EVP_MD_SHA3(256)
+EVP_MD_SHA3(384)
+EVP_MD_SHA3(512)
+
+#define EVP_MD_SHAKE(bitlen) \
+const EVP_MD *EVP_shake##bitlen(void) \
+{ \
+ static const EVP_MD shake##bitlen##_md = { \
+ NID_shake##bitlen, \
+ 0, \
+ 512, \
+ 0, \
+ shake_init, \
+ sha3_update, \
+ sha3_final, \
+ NULL, \
+ NULL, \
+ (KECCAK1600_WIDTH - bitlen * 2) / 8, \
+ sizeof(KECCAK1600_CTX), \
+ }; \
+ return &shake##bitlen##_md; \
+}
+
+EVP_MD_SHAKE(128)
+EVP_MD_SHAKE(256)