1 files changed, 138 insertions, 0 deletions

diff --git a/src/microhttpd/sha512_256.h b/src/microhttpd/sha512_256.h
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+++ b/src/microhttpd/sha512_256.h
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+/*
+     This file is part of GNU libmicrohttpd
+     Copyright (C) 2022 Karlson2k (Evgeny Grin)
+
+     GNU libmicrohttpd is free software; you can redistribute it and/or
+     modify it under the terms of the GNU Lesser General Public
+     License as published by the Free Software Foundation; either
+     version 2.1 of the License, or (at your option) any later version.
+
+     This library is distributed in the hope that it will be useful,
+     but WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     Lesser General Public License for more details.
+
+     You should have received a copy of the GNU Lesser General Public
+     License along with this library.
+     If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file microhttpd/sha512_256.h
+ * @brief  Calculation of SHA-512/256 digest
+ * @author Karlson2k (Evgeny Grin)
+ */
+
+#ifndef MHD_SHA512_256_H
+#define MHD_SHA512_256_H 1
+
+#include "mhd_options.h"
+#include <stdint.h>
+#ifdef HAVE_STDDEF_H
+#include <stddef.h>  /* for size_t */
+#endif /* HAVE_STDDEF_H */
+
+
+/**
+ * Number of bits in single SHA-512/256 word.
+ */
+#define SHA512_256_WORD_SIZE_BITS 64
+
+/**
+ * Number of bytes in single SHA-512/256 word.
+ */
+#define SHA512_256_BYTES_IN_WORD (SHA512_256_WORD_SIZE_BITS / 8)
+
+/**
+ * Hash is kept internally as 8 64-bit words.
+ * This is intermediate hash size, used during computing the final digest.
+ */
+#define SHA512_256_HASH_SIZE_WORDS 8
+
+/**
+ * Size of SHA-512/256 resulting digest in bytes.
+ * This is the final digest size, not intermediate hash.
+ */
+#define SHA512_256_DIGEST_SIZE_WORDS (SHA512_256_HASH_SIZE_WORDS  / 2)
+
+/**
+ * Size of SHA-512/256 resulting digest in bytes
+ * This is the final digest size, not intermediate hash.
+ */
+#define SHA512_256_DIGEST_SIZE \
+  (SHA512_256_DIGEST_SIZE_WORDS * SHA512_256_BYTES_IN_WORD)
+
+/**
+ * Size of SHA-512/256 digest string in chars including termination NUL.
+ */
+#define SHA512_256_DIGEST_STRING_SIZE ((SHA512_256_DIGEST_SIZE) * 2 + 1)
+
+/**
+ * Size of single processing block in bits.
+ * This is the final digest size, not intermediate hash.
+ */
+#define SHA512_256_BLOCK_SIZE_BITS 1024
+
+/**
+ * Size of single processing block in bytes.
+ */
+#define SHA512_256_BLOCK_SIZE (SHA512_256_BLOCK_SIZE_BITS / 8)
+
+/**
+ * Size of single processing block in words.
+ */
+#define SHA512_256_BLOCK_SIZE_WORDS \
+ (SHA512_256_BLOCK_SIZE_BITS / SHA512_256_WORD_SIZE_BITS)
+
+
+/**
+ * SHA-512/256 calculation context
+ */
+struct Sha512_256Ctx
+{
+  uint64_t H[SHA512_256_HASH_SIZE_WORDS];       /**< Intermediate hash value  */
+  uint64_t buffer[SHA512_256_BLOCK_SIZE_WORDS]; /**< SHA512_256 input data buffer */
+  /**
+   * The number of bytes, lower part
+   */
+  uint64_t count;
+  /**
+   * The number of bits, high part.
+   * Unlike lower part, this counts the number of bits, not bytes.
+   */
+  uint64_t count_bits_hi;
+};
+
+/**
+ * Initialise structure for SHA-512/256 calculation.
+ *
+ * @param ctx the calculation context
+ */
+void
+MHD_SHA512_256_init (struct Sha512_256Ctx *ctx);
+
+
+/**
+ * Process portion of bytes.
+ *
+ * @param ctx the calculation context
+ * @param data bytes to add to hash
+ * @param length number of bytes in @a data
+ */
+void
+MHD_SHA512_256_update (struct Sha512_256Ctx *ctx,
+                       const uint8_t *data,
+                       size_t length);
+
+
+/**
+ * Finalise SHA-512/256 calculation, return digest.
+ *
+ * @param ctx the calculation context
+ * @param[out] digest set to the hash, must be #SHA512_256_DIGEST_SIZE bytes
+ */
+void
+MHD_SHA512_256_finish (struct Sha512_256Ctx *ctx,
+                       uint8_t digest[SHA512_256_DIGEST_SIZE]);
+
+#endif /* MHD_SHA512_256_H */