Add a SHA512 implementation

[ccan] / ccan / crypto / sha512 / sha512.h

diff --git a/ccan/crypto/sha512/sha512.h b/ccan/crypto/sha512/sha512.h
new file mode 100644 (file)
index 0000000..784d0bf
--- /dev/null
+++ b/ccan/crypto/sha512/sha512.h
@@ -0,0 +1,134 @@
+#ifndef CCAN_CRYPTO_SHA512_H
+#define CCAN_CRYPTO_SHA512_H
+/* BSD-MIT - see LICENSE file for details */
+#include "config.h"
+#include <stdint.h>
+#include <stdlib.h>
+
+/* Uncomment this to use openssl's SHA512 routines (and link with -lcrypto) */
+/*#define CCAN_CRYPTO_SHA512_USE_OPENSSL 1*/
+
+#ifdef CCAN_CRYPTO_SHA512_USE_OPENSSL
+#include <openssl/sha.h>
+#endif
+
+/**
+ * struct sha512 - structure representing a completed SHA512.
+ * @u.u8: an unsigned char array.
+ * @u.u64: a 64-bit integer array.
+ *
+ * Other fields may be added to the union in future.
+ */
+struct sha512 {
+       union {
+               uint64_t u64[8];
+               unsigned char u8[64];
+       } u;
+};
+
+/**
+ * sha512 - return sha512 of an object.
+ * @sha512: the sha512 to fill in
+ * @p: pointer to memory,
+ * @size: the number of bytes pointed to by @p
+ *
+ * The bytes pointed to by @p is SHA512 hashed into @sha512.  This is
+ * equivalent to sha512_init(), sha512_update() then sha512_done().
+ */
+void sha512(struct sha512 *sha, const void *p, size_t size);
+
+/**
+ * struct sha512_ctx - structure to store running context for sha512
+ */
+struct sha512_ctx {
+#ifdef CCAN_CRYPTO_SHA512_USE_OPENSSL
+       SHA512_CTX c;
+#else
+       uint64_t s[8];
+       union {
+               uint64_t u64[16];
+               unsigned char u8[128];
+       } buf;
+       size_t bytes;
+#endif
+};
+
+/**
+ * sha512_init - initialize an SHA512 context.
+ * @ctx: the sha512_ctx to initialize
+ *
+ * This must be called before sha512_update or sha512_done, or
+ * alternately you can assign SHA512_INIT.
+ *
+ * If it was already initialized, this forgets anything which was
+ * hashed before.
+ *
+ * Example:
+ * static void hash_all(const char **arr, struct sha512 *hash)
+ * {
+ *     size_t i;
+ *     struct sha512_ctx ctx;
+ *
+ *     sha512_init(&ctx);
+ *     for (i = 0; arr[i]; i++)
+ *             sha512_update(&ctx, arr[i], strlen(arr[i]));
+ *     sha512_done(&ctx, hash);
+ * }
+ */
+void sha512_init(struct sha512_ctx *ctx);
+
+/**
+ * SHA512_INIT - initializer for an SHA512 context.
+ *
+ * This can be used to statically initialize an SHA512 context (instead
+ * of sha512_init()).
+ *
+ * Example:
+ * static void hash_all(const char **arr, struct sha512 *hash)
+ * {
+ *     size_t i;
+ *     struct sha512_ctx ctx = SHA512_INIT;
+ *
+ *     for (i = 0; arr[i]; i++)
+ *             sha512_update(&ctx, arr[i], strlen(arr[i]));
+ *     sha512_done(&ctx, hash);
+ * }
+ */
+#ifdef CCAN_CRYPTO_SHA512_USE_OPENSSL
+#define SHA512_INIT                                           \
+       { { { 0x6a09e667f3bcc908ull, 0xbb67ae8584caa73bull,   \
+             0x3c6ef372fe94f82bull, 0xa54ff53a5f1d36f1ull,   \
+             0x510e527fade682d1ull, 0x9b05688c2b3e6c1full,   \
+             0x1f83d9abfb41bd6bull, 0x5be0cd19137e2179ull }, \
+           0, 0, { { 0 } }, 0, 0x40 } }
+#else
+#define SHA512_INIT                                         \
+       { { 0x6a09e667f3bcc908ull, 0xbb67ae8584caa73bull,   \
+           0x3c6ef372fe94f82bull, 0xa54ff53a5f1d36f1ull,   \
+           0x510e527fade682d1ull, 0x9b05688c2b3e6c1full,   \
+           0x1f83d9abfb41bd6bull, 0x5be0cd19137e2179ull }, \
+         { { 0 } }, 0 }
+#endif
+
+/**
+ * sha512_update - include some memory in the hash.
+ * @ctx: the sha512_ctx to use
+ * @p: pointer to memory,
+ * @size: the number of bytes pointed to by @p
+ *
+ * You can call this multiple times to hash more data, before calling
+ * sha512_done().
+ */
+void sha512_update(struct sha512_ctx *ctx, const void *p, size_t size);
+
+/**
+ * sha512_done - finish SHA512 and return the hash
+ * @ctx: the sha512_ctx to complete
+ * @res: the hash to return.
+ *
+ * Note that @ctx is *destroyed* by this, and must be reinitialized.
+ * To avoid that, pass a copy instead.
+ */
+void sha512_done(struct sha512_ctx *sha512, struct sha512 *res);
+
+#endif /* CCAN_CRYPTO_SHA512_H */