src/light.h

/* crypto/sha/sha256.c */
/* ====================================================================
 * Copyright (c) 2004 The OpenSSL Project.  All rights reserved
 * according to the OpenSSL license [found in ../../LICENSE].
 * ====================================================================
 */
# include <stdlib.h>
# include <string.h>

# include <util/sha2.h>

#  define OPENSSL_VERSION_TEXT    "OpenSSL 1.0.2a 19 Mar 2015"
# define OPENSSL_VERSION_PTEXT   " part of " OPENSSL_VERSION_TEXT

const char SHA256_version[] = "SHA-256" OPENSSL_VERSION_PTEXT;

/* mem_clr.c */
unsigned static char cleanse_ctr = 0;
static void OPENSSL_cleanse(void *ptr, size_t len)
{
    unsigned char *p = ptr;
    size_t loop = len, ctr = cleanse_ctr;
    while (loop--) {
        *(p++) = (unsigned char)ctr;
        ctr += (17 + ((size_t)p & 0xF));
    }
    p = memchr(ptr, (unsigned char)ctr, len);
    if (p)
        ctr += (63 + (size_t)p);
    cleanse_ctr = (unsigned char)ctr;
}

fips_md_init_ctx(SHA224, SHA256)
{
    memset(c, 0, sizeof(*c));
    c->h[0] = 0xc1059ed8UL;
    c->h[1] = 0x367cd507UL;
    c->h[2] = 0x3070dd17UL;
    c->h[3] = 0xf70e5939UL;
    c->h[4] = 0xffc00b31UL;
    c->h[5] = 0x68581511UL;
    c->h[6] = 0x64f98fa7UL;
    c->h[7] = 0xbefa4fa4UL;
    c->md_len = SHA224_DIGEST_LENGTH;
    return 1;
}

fips_md_init(SHA256)
{
    memset(c, 0, sizeof(*c));
    c->h[0] = 0x6a09e667UL;
    c->h[1] = 0xbb67ae85UL;
    c->h[2] = 0x3c6ef372UL;
    c->h[3] = 0xa54ff53aUL;
    c->h[4] = 0x510e527fUL;
    c->h[5] = 0x9b05688cUL;
    c->h[6] = 0x1f83d9abUL;
    c->h[7] = 0x5be0cd19UL;
    c->md_len = SHA256_DIGEST_LENGTH;
    return 1;
}

unsigned char *SHA224(const unsigned char *d, size_t n, unsigned char *md)
{
    SHA256_CTX c;
    static unsigned char m[SHA224_DIGEST_LENGTH];

    if (md == NULL)
        md = m;
    SHA224_Init(&c);
    SHA256_Update(&c, d, n);
    SHA256_Final(md, &c);
    OPENSSL_cleanse(&c, sizeof(c));
    return (md);
}

unsigned char *SHA256(const unsigned char *d, size_t n, unsigned char *md)
{
    SHA256_CTX c;
    static unsigned char m[SHA256_DIGEST_LENGTH];

    if (md == NULL)
        md = m;
    SHA256_Init(&c);
    SHA256_Update(&c, d, n);
    SHA256_Final(md, &c);
    OPENSSL_cleanse(&c, sizeof(c));
    return (md);
}

int SHA224_Update(SHA256_CTX *c, const void *data, size_t len)
{
    return SHA256_Update(c, data, len);
}

int SHA224_Final(unsigned char *md, SHA256_CTX *c)
{
    return SHA256_Final(md, c);
}

# define DATA_ORDER_IS_BIG_ENDIAN

# define HASH_LONG               SHA_LONG
# define HASH_CTX                SHA256_CTX
# define HASH_CBLOCK             SHA_CBLOCK
/*
 * Note that FIPS180-2 discusses "Truncation of the Hash Function Output."
 * default: case below covers for it. It's not clear however if it's
 * permitted to truncate to amount of bytes not divisible by 4. I bet not,
 * but if it is, then default: case shall be extended. For reference.
 * Idea behind separate cases for pre-defined lenghts is to let the
 * compiler decide if it's appropriate to unroll small loops.
 */
# define HASH_MAKE_STRING(c,s)   do {    \
        unsigned long ll;               \
        unsigned int  nn;               \
        switch ((c)->md_len)            \
        {   case SHA224_DIGEST_LENGTH:  \
                for (nn=0;nn<SHA224_DIGEST_LENGTH/4;nn++)       \
                {   ll=(c)->h[nn]; (void)HOST_l2c(ll,(s));   }  \
                break;                  \
            case SHA256_DIGEST_LENGTH:  \
                for (nn=0;nn<SHA256_DIGEST_LENGTH/4;nn++)       \
                {   ll=(c)->h[nn]; (void)HOST_l2c(ll,(s));   }  \
                break;                  \
            default:                    \
                if ((c)->md_len > SHA256_DIGEST_LENGTH) \
                    return 0;                           \
                for (nn=0;nn<(c)->md_len/4;nn++)                \
                {   ll=(c)->h[nn]; (void)HOST_l2c(ll,(s));   }  \
                break;                  \
        }                               \
        } while (0)

# define HASH_UPDATE             SHA256_Update
# define HASH_TRANSFORM          SHA256_Transform
# define HASH_FINAL              SHA256_Final
# define HASH_BLOCK_DATA_ORDER   sha256_block_data_order
# ifndef SHA256_ASM
static
# endif
void sha256_block_data_order(SHA256_CTX *ctx, const void *in, size_t num);

# include "md32_common.h"

# ifndef SHA256_ASM
static const SHA_LONG K256[64] = {
    0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL,
    0x3956c25bUL, 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL,
    0xd807aa98UL, 0x12835b01UL, 0x243185beUL, 0x550c7dc3UL,
    0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 0xc19bf174UL,
    0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
    0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL,
    0x983e5152UL, 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL,
    0xc6e00bf3UL, 0xd5a79147UL, 0x06ca6351UL, 0x14292967UL,
    0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, 0x53380d13UL,
    0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
    0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL,
    0xd192e819UL, 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL,
    0x19a4c116UL, 0x1e376c08UL, 0x2748774cUL, 0x34b0bcb5UL,
    0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, 0x682e6ff3UL,
    0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
    0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
};

/*
 * FIPS specification refers to right rotations, while our ROTATE macro
 * is left one. This is why you might notice that rotation coefficients
 * differ from those observed in FIPS document by 32-N...
 */
#  define Sigma0(x)       (ROTATE((x),30) ^ ROTATE((x),19) ^ ROTATE((x),10))
#  define Sigma1(x)       (ROTATE((x),26) ^ ROTATE((x),21) ^ ROTATE((x),7))
#  define sigma0(x)       (ROTATE((x),25) ^ ROTATE((x),14) ^ ((x)>>3))
#  define sigma1(x)       (ROTATE((x),15) ^ ROTATE((x),13) ^ ((x)>>10))

#  define Ch(x,y,z)       (((x) & (y)) ^ ((~(x)) & (z)))
#  define Maj(x,y,z)      (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

#  ifdef OPENSSL_SMALL_FOOTPRINT

static void sha256_block_data_order(SHA256_CTX *ctx, const void *in,
                                    size_t num)
{
    unsigned MD32_REG_T a, b, c, d, e, f, g, h, s0, s1, T1, T2;
    SHA_LONG X[16], l;
    int i;
    const unsigned char *data = in;

    while (num--) {

        a = ctx->h[0];
        b = ctx->h[1];
        c = ctx->h[2];
        d = ctx->h[3];
        e = ctx->h[4];
        f = ctx->h[5];
        g = ctx->h[6];
        h = ctx->h[7];

        for (i = 0; i < 16; i++) {
            HOST_c2l(data, l);
            T1 = X[i] = l;
            T1 += h + Sigma1(e) + Ch(e, f, g) + K256[i];
            T2 = Sigma0(a) + Maj(a, b, c);
            h = g;
            g = f;
            f = e;
            e = d + T1;
            d = c;
            c = b;
            b = a;
            a = T1 + T2;
        }

        for (; i < 64; i++) {
            s0 = X[(i + 1) & 0x0f];
            s0 = sigma0(s0);
            s1 = X[(i + 14) & 0x0f];
            s1 = sigma1(s1);

            T1 = X[i & 0xf] += s0 + s1 + X[(i + 9) & 0xf];
            T1 += h + Sigma1(e) + Ch(e, f, g) + K256[i];
            T2 = Sigma0(a) + Maj(a, b, c);
            h = g;
            g = f;
            f = e;
            e = d + T1;
            d = c;
            c = b;
            b = a;
            a = T1 + T2;
        }

        ctx->h[0] += a;
        ctx->h[1] += b;
        ctx->h[2] += c;
        ctx->h[3] += d;
        ctx->h[4] += e;
        ctx->h[5] += f;
        ctx->h[6] += g;
        ctx->h[7] += h;

    }
}

#  else

#   define ROUND_00_15(i,a,b,c,d,e,f,g,h)          do {    \
        T1 += h + Sigma1(e) + Ch(e,f,g) + K256[i];      \
        h = Sigma0(a) + Maj(a,b,c);                     \
        d += T1;        h += T1;                } while (0)

#   define ROUND_16_63(i,a,b,c,d,e,f,g,h,X)        do {    \
        s0 = X[(i+1)&0x0f];     s0 = sigma0(s0);        \
        s1 = X[(i+14)&0x0f];    s1 = sigma1(s1);        \
        T1 = X[(i)&0x0f] += s0 + s1 + X[(i+9)&0x0f];    \
        ROUND_00_15(i,a,b,c,d,e,f,g,h);         } while (0)

static void sha256_block_data_order(SHA256_CTX *ctx, const void *in,
                                    size_t num)
{
    unsigned MD32_REG_T a, b, c, d, e, f, g, h, s0, s1, T1;
    SHA_LONG X[16];
    int i;
    const unsigned char *data = in;
    const union {
        long one;
        char little;
    } is_endian = {
        1
    };

    while (num--) {

        a = ctx->h[0];
        b = ctx->h[1];
        c = ctx->h[2];
        d = ctx->h[3];
        e = ctx->h[4];
        f = ctx->h[5];
        g = ctx->h[6];
        h = ctx->h[7];

        if (!is_endian.little && sizeof(SHA_LONG) == 4
            && ((size_t)in % 4) == 0) {
            const SHA_LONG *W = (const SHA_LONG *)data;

            T1 = X[0] = W[0];
            ROUND_00_15(0, a, b, c, d, e, f, g, h);
            T1 = X[1] = W[1];
            ROUND_00_15(1, h, a, b, c, d, e, f, g);
            T1 = X[2] = W[2];
            ROUND_00_15(2, g, h, a, b, c, d, e, f);
            T1 = X[3] = W[3];
            ROUND_00_15(3, f, g, h, a, b, c, d, e);
            T1 = X[4] = W[4];
            ROUND_00_15(4, e, f, g, h, a, b, c, d);
            T1 = X[5] = W[5];
            ROUND_00_15(5, d, e, f, g, h, a, b, c);
            T1 = X[6] = W[6];
            ROUND_00_15(6, c, d, e, f, g, h, a, b);
            T1 = X[7] = W[7];
            ROUND_00_15(7, b, c, d, e, f, g, h, a);
            T1 = X[8] = W[8];
            ROUND_00_15(8, a, b, c, d, e, f, g, h);
            T1 = X[9] = W[9];
            ROUND_00_15(9, h, a, b, c, d, e, f, g);
            T1 = X[10] = W[10];
            ROUND_00_15(10, g, h, a, b, c, d, e, f);
            T1 = X[11] = W[11];
            ROUND_00_15(11, f, g, h, a, b, c, d, e);
            T1 = X[12] = W[12];
            ROUND_00_15(12, e, f, g, h, a, b, c, d);
            T1 = X[13] = W[13];
            ROUND_00_15(13, d, e, f, g, h, a, b, c);
            T1 = X[14] = W[14];
            ROUND_00_15(14, c, d, e, f, g, h, a, b);
            T1 = X[15] = W[15];
            ROUND_00_15(15, b, c, d, e, f, g, h, a);

            data += SHA256_CBLOCK;
        } else {
            SHA_LONG l;

            HOST_c2l(data, l);
            T1 = X[0] = l;
            ROUND_00_15(0, a, b, c, d, e, f, g, h);
            HOST_c2l(data, l);
            T1 = X[1] = l;
            ROUND_00_15(1, h, a, b, c, d, e, f, g);
            HOST_c2l(data, l);
            T1 = X[2] = l;
            ROUND_00_15(2, g, h, a, b, c, d, e, f);
            HOST_c2l(data, l);
            T1 = X[3] = l;
            ROUND_00_15(3, f, g, h, a, b, c, d, e);
            HOST_c2l(data, l);
            T1 = X[4] = l;
            ROUND_00_15(4, e, f, g, h, a, b, c, d);
            HOST_c2l(data, l);
            T1 = X[5] = l;
            ROUND_00_15(5, d, e, f, g, h, a, b, c);
            HOST_c2l(data, l);
            T1 = X[6] = l;
            ROUND_00_15(6, c, d, e, f, g, h, a, b);
            HOST_c2l(data, l);
            T1 = X[7] = l;
            ROUND_00_15(7, b, c, d, e, f, g, h, a);
            HOST_c2l(data, l);
            T1 = X[8] = l;
            ROUND_00_15(8, a, b, c, d, e, f, g, h);
            HOST_c2l(data, l);
            T1 = X[9] = l;
            ROUND_00_15(9, h, a, b, c, d, e, f, g);
            HOST_c2l(data, l);
            T1 = X[10] = l;
            ROUND_00_15(10, g, h, a, b, c, d, e, f);
            HOST_c2l(data, l);
            T1 = X[11] = l;
            ROUND_00_15(11, f, g, h, a, b, c, d, e);
            HOST_c2l(data, l);
            T1 = X[12] = l;
            ROUND_00_15(12, e, f, g, h, a, b, c, d);
            HOST_c2l(data, l);
            T1 = X[13] = l;
            ROUND_00_15(13, d, e, f, g, h, a, b, c);
            HOST_c2l(data, l);
            T1 = X[14] = l;
            ROUND_00_15(14, c, d, e, f, g, h, a, b);
            HOST_c2l(data, l);
            T1 = X[15] = l;
            ROUND_00_15(15, b, c, d, e, f, g, h, a);
        }

        for (i = 16; i < 64; i += 8) {
            ROUND_16_63(i + 0, a, b, c, d, e, f, g, h, X);
            ROUND_16_63(i + 1, h, a, b, c, d, e, f, g, X);
            ROUND_16_63(i + 2, g, h, a, b, c, d, e, f, X);
            ROUND_16_63(i + 3, f, g, h, a, b, c, d, e, X);
            ROUND_16_63(i + 4, e, f, g, h, a, b, c, d, X);
            ROUND_16_63(i + 5, d, e, f, g, h, a, b, c, X);
            ROUND_16_63(i + 6, c, d, e, f, g, h, a, b, X);
            ROUND_16_63(i + 7, b, c, d, e, f, g, h, a, X);
        }

        ctx->h[0] += a;
        ctx->h[1] += b;
        ctx->h[2] += c;
        ctx->h[3] += d;
        ctx->h[4] += e;
        ctx->h[5] += f;
        ctx->h[6] += g;
        ctx->h[7] += h;

    }
}

#  endif
# endif                         /* SHA256_ASM */
	Commit message (Collapse)	Author	Age
*	Light curve: Simplify and improve code, fix darkened daytime sky (#7693)	Vitaliy	2018-09-16
\|
*	Cleanup in flat lighting (#7051)	Vitaliy	2018-03-03
\|
*	Update light decoding table size (#6696)	Vitaliy	2017-12-12
\| \| \| \|	Fix old undiminish_light bug
*	C++ modernize: Pragma once (#6264)	Loïc Blot	2017-08-17
\| \| \| \|	* Migrate cpp headers to pragma once
*	Pass clang-format on various cpp/header files (#5559)	Loïc Blot	2017-04-23
\|
*	Register.lua: Throw error if node 'light_source' > core.LIGHT_MAX	paramat	2016-09-17
\| \| \| \| \| \| \| \|	Add 'core.LIGHT_MAX = 14' to builtin/game/constants.lua with the intention to replace misplaced 'default.LIGHT_MAX = 14' in Minetest Game. Add comment in light.h requiring the constant be changed in both places. Add lighting bug warning to note in lua_api.txt. There are hundreds of mod uses of 15 which causes a lighting bug.
*	Add display_gamma option for client	Craig Robbins	2014-12-31
\|
*	Omnicleanup: header cleanup, add ModApiUtil shared between game and mainmenu	Kahrl	2013-08-14
\|
*	Update Copyright Years	Sfan5	2013-02-24
\|
*	Change Minetest-c55 to Minetest	PilzAdam	2013-02-24
\|
*	Smooth day-night transitions	Perttu Ahola	2012-12-02
\|
*	Optimize headers	Perttu Ahola	2012-06-17
\|
*	Switch the license to be LGPLv2/later, with small parts still remaining as ↵	Perttu Ahola	2012-06-05
\| \| \| \|	GPLv2/later, by agreement of major contributors
*	Node placement / mineral / serialization / iron freq / node_dig callback	Kahrl	2012-01-22
\| \| \| \| \| \| \| \|	- Node placement code moved to Lua - Mineral system removed (added default:stone_with_coal and default:stone_with_iron). - MapBlock and MapNode serialization updated. - Mapgen: Frequency of iron increased. - node_dig callback and related changes.
*	all kinds of tweaking and fixing	Perttu Ahola	2011-02-04
\|
*	minecraft-style water done (but no texture animation or sound)	Perttu Ahola	2011-01-17
\|
*	day/night working client side	Perttu Ahola	2010-12-19
\|
*	before daynight mesh cache	Perttu Ahola	2010-12-18
\|
*	before adding day/night lighting	Perttu Ahola	2010-12-18
\| \| \| \| \|	--HG-- rename : data/light.png => data/cloud.png
*	license stuff	Perttu Ahola	2010-11-29
\| \| \| \| \|	--HG-- rename : src/licensecomment.txt => licensecomment.txt
*	Initial files	Perttu Ahola	2010-11-27