/* See LICENSE file for copyright and license details. */
#ifndef LIBBLAKE_H
#define LIBBLAKE_H

#include <stddef.h>
#include <stdint.h>

#if defined(__clang__)
# pragma clang diagnostic push
# pragma clang diagnostic ignored "-Wpadded"
# pragma clang diagnostic ignored "-Wvla"
#endif

#ifndef LIBBLAKE_PUBLIC__
# if defined(_MSC_VER)
#  define LIBBLAKE_PUBLIC__ __declspec(dllexport)
# else
#  define LIBBLAKE_PUBLIC__
# endif
#endif

#if defined(__GNUC__)
# define LIBBLAKE_PURE__ __attribute__((__pure__))
# define LIBBLAKE_CONST__ __attribute__((__const__))
#else
# define LIBBLAKE_PURE__
# define LIBBLAKE_CONST__
#endif

#if defined(__STDC_VERSION__)
# if __STDC_VERSION__ >= 201112L
#  define LIBBLAKE_ALIGNED__(BYTES) _Alignas(BYTES)
# endif
#endif
#ifndef LIBBLAKE_ALIGNED__
# if defined(__GNUC__)
#  define LIBBLAKE_ALIGNED__(BYTES) __attribute__((__aligned__(BYTES)))
# else
#  define LIBBLAKE_ALIGNED__(BYTES)
# endif
#endif


LIBBLAKE_PUBLIC__ void libblake_init(void);

LIBBLAKE_PUBLIC__ void libblake_encode_hex(const void *data, size_t n, char out[/* static n * 2 + 1 */], int uppercase);
LIBBLAKE_PUBLIC__ size_t libblake_decode_hex(const char *data, size_t n, void *out, int *validp);


#define LIBBLAKE_BLAKE224_OUTPUT_SIZE (224 / 8)
#define LIBBLAKE_BLAKE256_OUTPUT_SIZE (256 / 8)
#define LIBBLAKE_BLAKE384_OUTPUT_SIZE (384 / 8)
#define LIBBLAKE_BLAKE512_OUTPUT_SIZE (512 / 8)

struct libblake_blakes_state {
	uint_least32_t h[8];
	uint_least32_t s[4];
	uint_least32_t t[2];
};

struct libblake_blakeb_state {
	uint_least64_t h[8];
	uint_least64_t s[4];
	uint_least64_t t[2];
};

struct libblake_blake224_state { struct libblake_blakes_state s; };
struct libblake_blake256_state { struct libblake_blakes_state s; };
struct libblake_blake384_state { struct libblake_blakeb_state b; };
struct libblake_blake512_state { struct libblake_blakeb_state b; };

LIBBLAKE_PUBLIC__ void libblake_blake224_init(struct libblake_blake224_state *state);
LIBBLAKE_PUBLIC__ void libblake_blake224_init2(struct libblake_blake224_state *state, uint_least8_t salt[16]);
LIBBLAKE_PUBLIC__ size_t libblake_blake224_update(struct libblake_blake224_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ void libblake_blake224_digest(struct libblake_blake224_state *state, void *data, size_t len, size_t bits,
                                                const char *suffix, unsigned char output[static LIBBLAKE_BLAKE224_OUTPUT_SIZE]);
LIBBLAKE_PUBLIC__ LIBBLAKE_PURE__ size_t libblake_blake224_digest_get_required_input_size(size_t len, size_t bits, const char *suffix);

LIBBLAKE_PUBLIC__ void libblake_blake256_init(struct libblake_blake256_state *state);
LIBBLAKE_PUBLIC__ void libblake_blake256_init2(struct libblake_blake256_state *state, uint_least8_t salt[16]);
LIBBLAKE_PUBLIC__ size_t libblake_blake256_update(struct libblake_blake256_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ void libblake_blake256_digest(struct libblake_blake256_state *state, void *data, size_t len, size_t bits,
                                                const char *suffix, unsigned char output[static LIBBLAKE_BLAKE256_OUTPUT_SIZE]);
LIBBLAKE_PUBLIC__ LIBBLAKE_PURE__ size_t libblake_blake256_digest_get_required_input_size(size_t len, size_t bits, const char *suffix);

LIBBLAKE_PUBLIC__ void libblake_blake384_init(struct libblake_blake384_state *state);
LIBBLAKE_PUBLIC__ void libblake_blake384_init2(struct libblake_blake384_state *state, uint_least8_t salt[32]);
LIBBLAKE_PUBLIC__ size_t libblake_blake384_update(struct libblake_blake384_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ void libblake_blake384_digest(struct libblake_blake384_state *state, void *data, size_t len, size_t bits,
                                                const char *suffix, unsigned char output[static LIBBLAKE_BLAKE384_OUTPUT_SIZE]);
LIBBLAKE_PUBLIC__ LIBBLAKE_PURE__ size_t libblake_blake384_digest_get_required_input_size(size_t len, size_t bits, const char *suffix);

LIBBLAKE_PUBLIC__ void libblake_blake512_init(struct libblake_blake512_state *state);
LIBBLAKE_PUBLIC__ void libblake_blake512_init2(struct libblake_blake512_state *state, uint_least8_t salt[32]);
LIBBLAKE_PUBLIC__ size_t libblake_blake512_update(struct libblake_blake512_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ void libblake_blake512_digest(struct libblake_blake512_state *state, void *data, size_t len, size_t bits,
                                                const char *suffix, unsigned char output[static LIBBLAKE_BLAKE512_OUTPUT_SIZE]);
LIBBLAKE_PUBLIC__ LIBBLAKE_PURE__ size_t libblake_blake512_digest_get_required_input_size(size_t len, size_t bits, const char *suffix);

struct libblake_blake2s_params {
	uint_least8_t digest_len; /* in bytes, [1, 32] */
	uint_least8_t key_len; /* in bytes, [0, 32] */
	uint_least8_t fanout; /* normally 1 */
	uint_least8_t depth; /* normally 1 */
	uint_least32_t leaf_len; /* normally 0 */
	uint_least64_t node_offset; /* (48-bits) normally 0 */
	uint_least8_t node_depth; /* normally 0 */
	uint_least8_t inner_len; /* normally 0 */
	uint_least8_t _padding[2]; /* to keep .salt and .pepper aligned as uint_least32_t */
	uint_least8_t salt[8];
	uint_least8_t pepper[8];
};

struct libblake_blake2b_params {
	uint_least8_t digest_len; /* in bytes, [1, 64] */
	uint_least8_t key_len; /* in bytes, [0, 64] */
	uint_least8_t fanout; /* normally 1 */
	uint_least8_t depth; /* normally 1 */
	uint_least32_t leaf_len; /* normally 0 */
	uint_least64_t node_offset; /* normally 0 */
	uint_least8_t node_depth; /* normally 0 */
	uint_least8_t inner_len; /* normally 0 */
	uint_least8_t _padding[6]; /* to keep .salt and .pepper aligned as uint_least64_t */
	uint_least8_t salt[16];
	uint_least8_t pepper[16];
};

struct libblake_blake2xs_params {
	uint_least8_t digest_len; /* in bytes, [1, 32] */
	uint_least8_t key_len; /* in bytes, [0, 32] */
	uint_least8_t fanout; /* normally 1 */
	uint_least8_t depth; /* normally 1 */
	uint_least32_t leaf_len; /* normally 0 */
	uint_least32_t node_offset; /* normally 0 */
	uint_least16_t xof_len; /* max if not known in advance */
	uint_least8_t node_depth; /* normally 0 */
	uint_least8_t inner_len; /* normally 0 */
	uint_least8_t salt[8];
	uint_least8_t pepper[8];
};

struct libblake_blake2xb_params {
	uint_least8_t digest_len; /* in bytes, [1, 64] */
	uint_least8_t key_len; /* in bytes, [0, 64] */
	uint_least8_t fanout; /* normally 1 */
	uint_least8_t depth; /* normally 1 */
	uint_least32_t leaf_len; /* normally 0 */
	uint_least32_t node_offset; /* normally 0 */
	uint_least32_t xof_len; /* max if not known in advance */
	uint_least8_t node_depth; /* normally 0 */
	uint_least8_t inner_len; /* normally 0 */
	uint_least8_t _padding[2]; /* to keep .salt and .pepper aligned as uint_least32_t */
	uint_least8_t salt[16];
	uint_least8_t pepper[16];
};

struct libblake_blake2s_state {
	LIBBLAKE_ALIGNED__(32)
	uint_least32_t h[8];
	uint_least32_t t[2];
	uint_least32_t f[2];
};

struct libblake_blake2b_state {
	LIBBLAKE_ALIGNED__(32)
	uint_least64_t h[8];
	uint_least64_t t[2];
	uint_least64_t f[2];
};

struct libblake_blake2xs_state {
	struct libblake_blake2s_state b2s;
	struct libblake_blake2xs_params xof_params;
	unsigned char intermediate[64];
};

struct libblake_blake2xb_state {
	struct libblake_blake2b_state b2b;
	struct libblake_blake2xb_params xof_params;
	unsigned char intermediate[128];
};

LIBBLAKE_PUBLIC__ void libblake_blake2s_init(struct libblake_blake2s_state *state, const struct libblake_blake2s_params *params,
                                             const unsigned char *key /* append null bytes until 64 bytes; if key is used */);
LIBBLAKE_PUBLIC__ size_t libblake_blake2s_update(struct libblake_blake2s_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ size_t libblake_blake2s_force_update(struct libblake_blake2s_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ void libblake_blake2s_digest(struct libblake_blake2s_state *state, void *data, size_t len,
                                               int last_node /* normally 0 */, size_t output_len,
                                               unsigned char output[static output_len]);
LIBBLAKE_PUBLIC__ LIBBLAKE_CONST__ size_t libblake_blake2s_digest_get_required_input_size(size_t len);

LIBBLAKE_PUBLIC__ void libblake_blake2b_init(struct libblake_blake2b_state *state, const struct libblake_blake2b_params *params,
                                             const unsigned char *key /* append null bytes until 128 bytes; if key is used */);
LIBBLAKE_PUBLIC__ size_t libblake_blake2b_update(struct libblake_blake2b_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ size_t libblake_blake2b_force_update(struct libblake_blake2b_state *state, const void *data, size_t len);
LIBBLAKE_PUBLIC__ void libblake_blake2b_digest(struct libblake_blake2b_state *state, void *data, size_t len,
                                               int last_node /* normally 0 */, size_t output_len,
                                               unsigned char output[static output_len]);
LIBBLAKE_PUBLIC__ LIBBLAKE_CONST__ size_t libblake_blake2b_digest_get_required_input_size(size_t len);

LIBBLAKE_PUBLIC__ void libblake_blake2xs_init(struct libblake_blake2xs_state *state, const struct libblake_blake2xs_params *params,
                                              const unsigned char *key /* append null bytes until 64 bytes; if key is used */);
LIBBLAKE_PUBLIC__ inline size_t
libblake_blake2xs_update(struct libblake_blake2xs_state *state, const void *data, size_t len) {
	return libblake_blake2s_update(&state->b2s, data, len);
}
LIBBLAKE_PUBLIC__ inline size_t
libblake_blake2xs_force_update(struct libblake_blake2xs_state *state, const void *data, size_t len) {
	return libblake_blake2s_force_update(&state->b2s, data, len);
}
LIBBLAKE_PUBLIC__ inline void
libblake_blake2xs_predigest(struct libblake_blake2xs_state *state, void *data, size_t len, int last_node) {
	libblake_blake2s_digest(&state->b2s, data, len, last_node, (size_t)state->xof_params.digest_len, state->intermediate);
}
LIBBLAKE_PUBLIC__ LIBBLAKE_PURE__ inline size_t
libblake_blake2xs_predigest_get_required_input_size(const struct libblake_blake2xs_state *state) {
	return libblake_blake2s_digest_get_required_input_size((size_t)state->xof_params.digest_len);
}
LIBBLAKE_PUBLIC__ void libblake_blake2xs_digest(const struct libblake_blake2xs_state *state,
                                                uint_least32_t i /* start 0, increase by 1 until i * 32 >= desired hash length */,
                                                uint_least8_t len /* desired hash MIN(length - i * 32, 32) */,
                                                unsigned char output[static len]  /* output for hash offset by i * 32 */);

LIBBLAKE_PUBLIC__ void libblake_blake2xb_init(struct libblake_blake2xb_state *state, const struct libblake_blake2xb_params *params,
                                              const unsigned char *key /* append null bytes until 128 bytes; if key is used */);
LIBBLAKE_PUBLIC__ inline size_t
libblake_blake2xb_update(struct libblake_blake2xb_state *state, const void *data, size_t len) {
	return libblake_blake2b_update(&state->b2b, data, len);
}
LIBBLAKE_PUBLIC__ inline size_t
libblake_blake2xb_force_update(struct libblake_blake2xb_state *state, const void *data, size_t len) {
	return libblake_blake2b_update(&state->b2b, data, len);
}
LIBBLAKE_PUBLIC__ inline void
libblake_blake2xb_predigest(struct libblake_blake2xb_state *state, void *data, size_t len, int last_node) {
	libblake_blake2b_digest(&state->b2b, data, len, last_node, state->xof_params.digest_len, state->intermediate);
}
LIBBLAKE_PUBLIC__ LIBBLAKE_PURE__ inline size_t
libblake_blake2xb_predigest_get_required_input_size(const struct libblake_blake2xb_state *state) {
	return libblake_blake2b_digest_get_required_input_size((size_t)state->xof_params.digest_len);
}
LIBBLAKE_PUBLIC__ void libblake_blake2xb_digest(const struct libblake_blake2xb_state *state,
                                                uint_least32_t i /* start 0, increase by 1 until i * 64 >= desired hash length */,
                                                uint_least8_t len /* desired hash MIN(length - i * 64, 64) */,
                                                unsigned char output[static len] /* output for hash offset by i * 64 */);

#if defined(__clang__)
# pragma clang diagnostic pop
#endif

#endif