#include <mio-utl.h>
#include <string.h>
#include <stdio.h>

/* https://131002.net/siphash/siphash24.c */




/*
   SipHash reference C implementation

   Copyright (c) 2012-2016 Jean-Philippe Aumasson
   <jeanphilippe.aumasson@gmail.com>
   Copyright (c) 2012-2014 Daniel J. Bernstein <djb@cr.yp.to>

   To the extent possible under law, the author(s) have dedicated all copyright
   and related and neighboring rights to this software to the public domain
   worldwide. This software is distributed without any warranty.

   You should have received a copy of the CC0 Public Domain Dedication along
   with
   this software. If not, see
   <http://creativecommons.org/publicdomain/zero/1.0/>.
 */
#include <assert.h>
#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

/* default: SipHash-2-4 */
#ifndef cROUNDS
    #define cROUNDS 2
#endif
#ifndef dROUNDS
    #define dROUNDS 4
#endif

#define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b))))

#define U32TO8_LE(p, v)                                                        \
    (p)[0] = (uint8_t)((v));                                                   \
    (p)[1] = (uint8_t)((v) >> 8);                                              \
    (p)[2] = (uint8_t)((v) >> 16);                                             \
    (p)[3] = (uint8_t)((v) >> 24);

#define U64TO8_LE(p, v)                                                        \
    U32TO8_LE((p), (uint32_t)((v)));                                           \
    U32TO8_LE((p) + 4, (uint32_t)((v) >> 32));

#define U8TO64_LE(p)                                                           \
    (((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) |                        \
     ((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) |                 \
     ((uint64_t)((p)[4]) << 32) | ((uint64_t)((p)[5]) << 40) |                 \
     ((uint64_t)((p)[6]) << 48) | ((uint64_t)((p)[7]) << 56))

#define SIPROUND                                                               \
    do {                                                                       \
        v0 += v1;                                                              \
        v1 = ROTL(v1, 13);                                                     \
        v1 ^= v0;                                                              \
        v0 = ROTL(v0, 32);                                                     \
        v2 += v3;                                                              \
        v3 = ROTL(v3, 16);                                                     \
        v3 ^= v2;                                                              \
        v0 += v3;                                                              \
        v3 = ROTL(v3, 21);                                                     \
        v3 ^= v0;                                                              \
        v2 += v1;                                                              \
        v1 = ROTL(v1, 17);                                                     \
        v1 ^= v2;                                                              \
        v2 = ROTL(v2, 32);                                                     \
    } while (0)

#ifdef DEBUG
#define TRACE                                                                  \
    do {                                                                       \
        printf("(%3zu) v0 %016"PRIx64"\n", inlen, v0);                         \
        printf("(%3zu) v1 %016"PRIx64"\n", inlen, v1);                         \
        printf("(%3zu) v2 %016"PRIx64"\n", inlen, v2);                         \
        printf("(%3zu) v3 %016"PRIx64"\n", inlen, v3);                         \
    } while (0)
#else
#define TRACE
#endif

int siphash(const uint8_t *in, const size_t inlen, const uint8_t *k,
            uint8_t *out, const size_t outlen) {

    assert((outlen == 8) || (outlen == 16));
    uint64_t v0 = UINT64_C(0x736f6d6570736575);
    uint64_t v1 = UINT64_C(0x646f72616e646f6d);
    uint64_t v2 = UINT64_C(0x6c7967656e657261);
    uint64_t v3 = UINT64_C(0x7465646279746573);
    uint64_t k0 = U8TO64_LE(k);
    uint64_t k1 = U8TO64_LE(k + 8);
    uint64_t m;
    int i;
    const uint8_t *end = in + inlen - (inlen % sizeof(uint64_t));
    const int left = inlen & 7;
    uint64_t b = ((uint64_t)inlen) << 56;
    v3 ^= k1;
    v2 ^= k0;
    v1 ^= k1;
    v0 ^= k0;

    if (outlen == 16)
        v1 ^= 0xee;

    for (; in != end; in += 8) {
        m = U8TO64_LE(in);
        v3 ^= m;

        TRACE;
        for (i = 0; i < cROUNDS; ++i)
            SIPROUND;

        v0 ^= m;
    }

    switch (left) {
    case 7:
        b |= ((uint64_t)in[6]) << 48;
    case 6:
        b |= ((uint64_t)in[5]) << 40;
    case 5:
        b |= ((uint64_t)in[4]) << 32;
    case 4:
        b |= ((uint64_t)in[3]) << 24;
    case 3:
        b |= ((uint64_t)in[2]) << 16;
    case 2:
        b |= ((uint64_t)in[1]) << 8;
    case 1:
        b |= ((uint64_t)in[0]);
        break;
    case 0:
        break;
    }

    v3 ^= b;

    TRACE;
    for (i = 0; i < cROUNDS; ++i)
        SIPROUND;

    v0 ^= b;

    if (outlen == 16)
        v2 ^= 0xee;
    else
        v2 ^= 0xff;

    TRACE;
    for (i = 0; i < dROUNDS; ++i)
        SIPROUND;

    b = v0 ^ v1 ^ v2 ^ v3;
    U64TO8_LE(out, b);

    if (outlen == 8)
        return 0;

    v1 ^= 0xdd;

    TRACE;
    for (i = 0; i < dROUNDS; ++i)
        SIPROUND;

    b = v0 ^ v1 ^ v2 ^ v3;
    U64TO8_LE(out + 8, b);

    return 0;
}

/*
   SipHash-2-4 output with
   k = 00 01 02 ...
   and
   in = (empty string)
   in = 00 (1 byte)
   in = 00 01 (2 bytes)
   in = 00 01 02 (3 bytes)
   ...
   in = 00 01 02 ... 3e (63 bytes)
*/
mio_uint8_t vectors[64][8] =
{
	{ 0x31, 0x0e, 0x0e, 0xdd, 0x47, 0xdb, 0x6f, 0x72, },
	{ 0xfd, 0x67, 0xdc, 0x93, 0xc5, 0x39, 0xf8, 0x74, },
	{ 0x5a, 0x4f, 0xa9, 0xd9, 0x09, 0x80, 0x6c, 0x0d, },
	{ 0x2d, 0x7e, 0xfb, 0xd7, 0x96, 0x66, 0x67, 0x85, },
	{ 0xb7, 0x87, 0x71, 0x27, 0xe0, 0x94, 0x27, 0xcf, },
	{ 0x8d, 0xa6, 0x99, 0xcd, 0x64, 0x55, 0x76, 0x18, },
	{ 0xce, 0xe3, 0xfe, 0x58, 0x6e, 0x46, 0xc9, 0xcb, },
	{ 0x37, 0xd1, 0x01, 0x8b, 0xf5, 0x00, 0x02, 0xab, },
	{ 0x62, 0x24, 0x93, 0x9a, 0x79, 0xf5, 0xf5, 0x93, },
	{ 0xb0, 0xe4, 0xa9, 0x0b, 0xdf, 0x82, 0x00, 0x9e, },
	{ 0xf3, 0xb9, 0xdd, 0x94, 0xc5, 0xbb, 0x5d, 0x7a, },
	{ 0xa7, 0xad, 0x6b, 0x22, 0x46, 0x2f, 0xb3, 0xf4, },
	{ 0xfb, 0xe5, 0x0e, 0x86, 0xbc, 0x8f, 0x1e, 0x75, },
	{ 0x90, 0x3d, 0x84, 0xc0, 0x27, 0x56, 0xea, 0x14, },
	{ 0xee, 0xf2, 0x7a, 0x8e, 0x90, 0xca, 0x23, 0xf7, },
	{ 0xe5, 0x45, 0xbe, 0x49, 0x61, 0xca, 0x29, 0xa1, },
	{ 0xdb, 0x9b, 0xc2, 0x57, 0x7f, 0xcc, 0x2a, 0x3f, },
	{ 0x94, 0x47, 0xbe, 0x2c, 0xf5, 0xe9, 0x9a, 0x69, },
	{ 0x9c, 0xd3, 0x8d, 0x96, 0xf0, 0xb3, 0xc1, 0x4b, },
	{ 0xbd, 0x61, 0x79, 0xa7, 0x1d, 0xc9, 0x6d, 0xbb, },
	{ 0x98, 0xee, 0xa2, 0x1a, 0xf2, 0x5c, 0xd6, 0xbe, },
	{ 0xc7, 0x67, 0x3b, 0x2e, 0xb0, 0xcb, 0xf2, 0xd0, },
	{ 0x88, 0x3e, 0xa3, 0xe3, 0x95, 0x67, 0x53, 0x93, },
	{ 0xc8, 0xce, 0x5c, 0xcd, 0x8c, 0x03, 0x0c, 0xa8, },
	{ 0x94, 0xaf, 0x49, 0xf6, 0xc6, 0x50, 0xad, 0xb8, },
	{ 0xea, 0xb8, 0x85, 0x8a, 0xde, 0x92, 0xe1, 0xbc, },
	{ 0xf3, 0x15, 0xbb, 0x5b, 0xb8, 0x35, 0xd8, 0x17, },
	{ 0xad, 0xcf, 0x6b, 0x07, 0x63, 0x61, 0x2e, 0x2f, },
	{ 0xa5, 0xc9, 0x1d, 0xa7, 0xac, 0xaa, 0x4d, 0xde, },
	{ 0x71, 0x65, 0x95, 0x87, 0x66, 0x50, 0xa2, 0xa6, },
	{ 0x28, 0xef, 0x49, 0x5c, 0x53, 0xa3, 0x87, 0xad, },
	{ 0x42, 0xc3, 0x41, 0xd8, 0xfa, 0x92, 0xd8, 0x32, },
	{ 0xce, 0x7c, 0xf2, 0x72, 0x2f, 0x51, 0x27, 0x71, },
	{ 0xe3, 0x78, 0x59, 0xf9, 0x46, 0x23, 0xf3, 0xa7, },
	{ 0x38, 0x12, 0x05, 0xbb, 0x1a, 0xb0, 0xe0, 0x12, },
	{ 0xae, 0x97, 0xa1, 0x0f, 0xd4, 0x34, 0xe0, 0x15, },
	{ 0xb4, 0xa3, 0x15, 0x08, 0xbe, 0xff, 0x4d, 0x31, },
	{ 0x81, 0x39, 0x62, 0x29, 0xf0, 0x90, 0x79, 0x02, },
	{ 0x4d, 0x0c, 0xf4, 0x9e, 0xe5, 0xd4, 0xdc, 0xca, },
	{ 0x5c, 0x73, 0x33, 0x6a, 0x76, 0xd8, 0xbf, 0x9a, },
	{ 0xd0, 0xa7, 0x04, 0x53, 0x6b, 0xa9, 0x3e, 0x0e, },
	{ 0x92, 0x59, 0x58, 0xfc, 0xd6, 0x42, 0x0c, 0xad, },
	{ 0xa9, 0x15, 0xc2, 0x9b, 0xc8, 0x06, 0x73, 0x18, },
	{ 0x95, 0x2b, 0x79, 0xf3, 0xbc, 0x0a, 0xa6, 0xd4, },
	{ 0xf2, 0x1d, 0xf2, 0xe4, 0x1d, 0x45, 0x35, 0xf9, },
	{ 0x87, 0x57, 0x75, 0x19, 0x04, 0x8f, 0x53, 0xa9, },
	{ 0x10, 0xa5, 0x6c, 0xf5, 0xdf, 0xcd, 0x9a, 0xdb, },
	{ 0xeb, 0x75, 0x09, 0x5c, 0xcd, 0x98, 0x6c, 0xd0, },
	{ 0x51, 0xa9, 0xcb, 0x9e, 0xcb, 0xa3, 0x12, 0xe6, },
	{ 0x96, 0xaf, 0xad, 0xfc, 0x2c, 0xe6, 0x66, 0xc7, },
	{ 0x72, 0xfe, 0x52, 0x97, 0x5a, 0x43, 0x64, 0xee, },
	{ 0x5a, 0x16, 0x45, 0xb2, 0x76, 0xd5, 0x92, 0xa1, },
	{ 0xb2, 0x74, 0xcb, 0x8e, 0xbf, 0x87, 0x87, 0x0a, },
	{ 0x6f, 0x9b, 0xb4, 0x20, 0x3d, 0xe7, 0xb3, 0x81, },
	{ 0xea, 0xec, 0xb2, 0xa3, 0x0b, 0x22, 0xa8, 0x7f, },
	{ 0x99, 0x24, 0xa4, 0x3c, 0xc1, 0x31, 0x57, 0x24, },
	{ 0xbd, 0x83, 0x8d, 0x3a, 0xaf, 0xbf, 0x8d, 0xb7, },
	{ 0x0b, 0x1a, 0x2a, 0x32, 0x65, 0xd5, 0x1a, 0xea, },
	{ 0x13, 0x50, 0x79, 0xa3, 0x23, 0x1c, 0xe6, 0x60, },
	{ 0x93, 0x2b, 0x28, 0x46, 0xe4, 0xd7, 0x06, 0x66, },
	{ 0xe1, 0x91, 0x5f, 0x5c, 0xb1, 0xec, 0xa4, 0x6c, },
	{ 0xf3, 0x25, 0x96, 0x5c, 0xa1, 0x6d, 0x62, 0x9f, },
	{ 0x57, 0x5f, 0xf2, 0x8e, 0x60, 0x38, 0x1b, 0xe5, },
	{ 0x72, 0x45, 0x06, 0xeb, 0x4c, 0x32, 0x8a, 0x95, }
};


int test_vectors()
{
#define MAXLEN 64

	mio_uint8_t in[MAXLEN], out[8], k[16];
	int i;
	int ok = 1;

	for( i = 0; i < 16; ++i ) k[i] = i;

	for( i = 0; i < MAXLEN; ++i )
	{
		in[i] = i;
		mio_sip_hash_24(k, in, i, out);
	//	siphash(in, i, k, out, 8);

		if ( memcmp( out, vectors[i], 8 ) )
		{
			printf( "test vector failed for %d bytes\n", i );
			ok = 0;
		}
	}

	return ok;
}

int main()
{
	if (test_vectors()) printf( "test vectors ok\n" );
	return 0;
}