crypto/bf/bf_local.h

/*
 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#ifndef OSSL_CRYPTO_BF_LOCAL_H
#define OSSL_CRYPTO_BF_LOCAL_H
#include <openssl/opensslconf.h>

/* NOTE - c is not incremented as per n2l */
#define n2ln(c, l1, l2, n)                           \
    {                                                \
        c += n;                                      \
        l1 = l2 = 0;                                 \
        switch (n) {                                 \
        case 8:                                      \
            l2 = ((unsigned long)(*(--(c))));        \
        /* fall through */                           \
        case 7:                                      \
            l2 |= ((unsigned long)(*(--(c)))) << 8;  \
        /* fall through */                           \
        case 6:                                      \
            l2 |= ((unsigned long)(*(--(c)))) << 16; \
        /* fall through */                           \
        case 5:                                      \
            l2 |= ((unsigned long)(*(--(c)))) << 24; \
        /* fall through */                           \
        case 4:                                      \
            l1 = ((unsigned long)(*(--(c))));        \
        /* fall through */                           \
        case 3:                                      \
            l1 |= ((unsigned long)(*(--(c)))) << 8;  \
        /* fall through */                           \
        case 2:                                      \
            l1 |= ((unsigned long)(*(--(c)))) << 16; \
        /* fall through */                           \
        case 1:                                      \
            l1 |= ((unsigned long)(*(--(c)))) << 24; \
        }                                            \
    }

/* NOTE - c is not incremented as per l2n */
#define l2nn(l1, l2, c, n)                                   \
    {                                                        \
        c += n;                                              \
        switch (n) {                                         \
        case 8:                                              \
            *(--(c)) = (unsigned char)(((l2)) & 0xff);       \
        /* fall through */                                   \
        case 7:                                              \
            *(--(c)) = (unsigned char)(((l2) >> 8) & 0xff);  \
        /* fall through */                                   \
        case 6:                                              \
            *(--(c)) = (unsigned char)(((l2) >> 16) & 0xff); \
        /* fall through */                                   \
        case 5:                                              \
            *(--(c)) = (unsigned char)(((l2) >> 24) & 0xff); \
        /* fall through */                                   \
        case 4:                                              \
            *(--(c)) = (unsigned char)(((l1)) & 0xff);       \
        /* fall through */                                   \
        case 3:                                              \
            *(--(c)) = (unsigned char)(((l1) >> 8) & 0xff);  \
        /* fall through */                                   \
        case 2:                                              \
            *(--(c)) = (unsigned char)(((l1) >> 16) & 0xff); \
        /* fall through */                                   \
        case 1:                                              \
            *(--(c)) = (unsigned char)(((l1) >> 24) & 0xff); \
        }                                                    \
    }

#undef n2l
#define n2l(c, l) (l = ((unsigned long)(*((c)++))) << 24L, \
    l |= ((unsigned long)(*((c)++))) << 16L,               \
    l |= ((unsigned long)(*((c)++))) << 8L,                \
    l |= ((unsigned long)(*((c)++))))

#undef l2n
#define l2n(l, c) (*((c)++) = (unsigned char)(((l) >> 24L) & 0xff), \
    *((c)++) = (unsigned char)(((l) >> 16L) & 0xff),                \
    *((c)++) = (unsigned char)(((l) >> 8L) & 0xff),                 \
    *((c)++) = (unsigned char)(((l)) & 0xff))

/*
 * This is actually a big endian algorithm, the most significant byte is used
 * to lookup array 0
 */

#define BF_ENC(LL, R, S, P) ( \
    LL ^= P,                  \
    LL ^= (((S[((R >> 24) & 0xff)] + S[0x0100 + ((R >> 16) & 0xff)]) ^ S[0x0200 + ((R >> 8) & 0xff)]) + S[0x0300 + ((R) & 0xff)]) & 0xffffffffU)

#endif