/* $OpenBSD: md4.c,v 1.18 2024/06/01 07:36:16 tb Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#include <openssl/opensslconf.h>

#include <openssl/md4.h>

#include "crypto_internal.h"

/* Ensure that MD4_LONG and uint32_t are equivalent size. */
CTASSERT(sizeof(MD4_LONG) == sizeof(uint32_t));

static inline uint32_t
md4_f(uint32_t x, uint32_t y, uint32_t z)
{
        return (x & y) | (~x & z);
}

static inline uint32_t
md4_g(uint32_t x, uint32_t y, uint32_t z)
{
        return (x & y) | (x & z) | (y & z);
}

static inline uint32_t
md4_h(uint32_t x, uint32_t y, uint32_t z)
{
        return x ^ y ^ z;
}

static inline void
md4_round1(uint32_t *a, uint32_t b, uint32_t c, uint32_t d, uint32_t x,
    uint32_t s)
{
        *a = crypto_rol_u32(*a + md4_f(b, c, d) + x, s);
}

static inline void
md4_round2(uint32_t *a, uint32_t b, uint32_t c, uint32_t d, uint32_t x,
    uint32_t s)
{
        *a = crypto_rol_u32(*a + md4_g(b, c, d) + x + 0x5a827999UL, s);
}

static inline void
md4_round3(uint32_t *a, uint32_t b, uint32_t c, uint32_t d, uint32_t x,
    uint32_t s)
{
        *a = crypto_rol_u32(*a + md4_h(b, c, d) + x + 0x6ed9eba1UL, s);
}

static void
md4_block_data_order(MD4_CTX *c, const void *_in, size_t num)
{
        const uint8_t *in = _in;
        const MD4_LONG *in32;
        unsigned int A, B, C, D;
        unsigned int X0, X1, X2, X3, X4, X5, X6, X7,
            X8, X9, X10, X11, X12, X13, X14, X15;

        while (num-- > 0) {
                A = c->A;
                B = c->B;
                C = c->C;
                D = c->D;

                if ((uintptr_t)in % 4 == 0) {
                        /* Input is 32 bit aligned. */
                        in32 = (const MD4_LONG *)in;
                        X0 = le32toh(in32[0]);
                        X1 = le32toh(in32[1]);
                        X2 = le32toh(in32[2]);
                        X3 = le32toh(in32[3]);
                        X4 = le32toh(in32[4]);
                        X5 = le32toh(in32[5]);
                        X6 = le32toh(in32[6]);
                        X7 = le32toh(in32[7]);
                        X8 = le32toh(in32[8]);
                        X9 = le32toh(in32[9]);
                        X10 = le32toh(in32[10]);
                        X11 = le32toh(in32[11]);
                        X12 = le32toh(in32[12]);
                        X13 = le32toh(in32[13]);
                        X14 = le32toh(in32[14]);
                        X15 = le32toh(in32[15]);
                } else {
                        /* Input is not 32 bit aligned. */
                        X0 = crypto_load_le32toh(&in[0 * 4]);
                        X1 = crypto_load_le32toh(&in[1 * 4]);
                        X2 = crypto_load_le32toh(&in[2 * 4]);
                        X3 = crypto_load_le32toh(&in[3 * 4]);
                        X4 = crypto_load_le32toh(&in[4 * 4]);
                        X5 = crypto_load_le32toh(&in[5 * 4]);
                        X6 = crypto_load_le32toh(&in[6 * 4]);
                        X7 = crypto_load_le32toh(&in[7 * 4]);
                        X8 = crypto_load_le32toh(&in[8 * 4]);
                        X9 = crypto_load_le32toh(&in[9 * 4]);
                        X10 = crypto_load_le32toh(&in[10 * 4]);
                        X11 = crypto_load_le32toh(&in[11 * 4]);
                        X12 = crypto_load_le32toh(&in[12 * 4]);
                        X13 = crypto_load_le32toh(&in[13 * 4]);
                        X14 = crypto_load_le32toh(&in[14 * 4]);
                        X15 = crypto_load_le32toh(&in[15 * 4]);
                }
                in += MD4_CBLOCK;

                md4_round1(&A, B, C, D, X0, 3);
                md4_round1(&D, A, B, C, X1, 7);
                md4_round1(&C, D, A, B, X2, 11);
                md4_round1(&B, C, D, A, X3, 19);
                md4_round1(&A, B, C, D, X4, 3);
                md4_round1(&D, A, B, C, X5, 7);
                md4_round1(&C, D, A, B, X6, 11);
                md4_round1(&B, C, D, A, X7, 19);
                md4_round1(&A, B, C, D, X8, 3);
                md4_round1(&D, A, B, C, X9, 7);
                md4_round1(&C, D, A, B, X10, 11);
                md4_round1(&B, C, D, A, X11, 19);
                md4_round1(&A, B, C, D, X12, 3);
                md4_round1(&D, A, B, C, X13, 7);
                md4_round1(&C, D, A, B, X14, 11);
                md4_round1(&B, C, D, A, X15, 19);

                /* Round 1 */
                md4_round2(&A, B, C, D, X0, 3);
                md4_round2(&D, A, B, C, X4, 5);
                md4_round2(&C, D, A, B, X8, 9);
                md4_round2(&B, C, D, A, X12, 13);
                md4_round2(&A, B, C, D, X1, 3);
                md4_round2(&D, A, B, C, X5, 5);
                md4_round2(&C, D, A, B, X9, 9);
                md4_round2(&B, C, D, A, X13, 13);
                md4_round2(&A, B, C, D, X2, 3);
                md4_round2(&D, A, B, C, X6, 5);
                md4_round2(&C, D, A, B, X10, 9);
                md4_round2(&B, C, D, A, X14, 13);
                md4_round2(&A, B, C, D, X3, 3);
                md4_round2(&D, A, B, C, X7, 5);
                md4_round2(&C, D, A, B, X11, 9);
                md4_round2(&B, C, D, A, X15, 13);

                /* Round 2 */
                md4_round3(&A, B, C, D, X0, 3);
                md4_round3(&D, A, B, C, X8, 9);
                md4_round3(&C, D, A, B, X4, 11);
                md4_round3(&B, C, D, A, X12, 15);
                md4_round3(&A, B, C, D, X2, 3);
                md4_round3(&D, A, B, C, X10, 9);
                md4_round3(&C, D, A, B, X6, 11);
                md4_round3(&B, C, D, A, X14, 15);
                md4_round3(&A, B, C, D, X1, 3);
                md4_round3(&D, A, B, C, X9, 9);
                md4_round3(&C, D, A, B, X5, 11);
                md4_round3(&B, C, D, A, X13, 15);
                md4_round3(&A, B, C, D, X3, 3);
                md4_round3(&D, A, B, C, X11, 9);
                md4_round3(&C, D, A, B, X7, 11);
                md4_round3(&B, C, D, A, X15, 15);

                c->A += A;
                c->B += B;
                c->C += C;
                c->D += D;
        }
}

int
MD4_Init(MD4_CTX *c)
{
        memset(c, 0, sizeof(*c));

        c->A = 0x67452301UL;
        c->B = 0xefcdab89UL;
        c->C = 0x98badcfeUL;
        c->D = 0x10325476UL;

        return 1;
}
LCRYPTO_ALIAS(MD4_Init);

int
MD4_Update(MD4_CTX *c, const void *data_, size_t len)
{
        const unsigned char *data = data_;
        unsigned char *p;
        MD4_LONG l;
        size_t n;

        if (len == 0)
                return 1;

        l = (c->Nl + (((MD4_LONG)len) << 3))&0xffffffffUL;
        /* 95-05-24 eay Fixed a bug with the overflow handling, thanks to
         * Wei Dai <weidai@eskimo.com> for pointing it out. */
        if (l < c->Nl) /* overflow */
                c->Nh++;
        c->Nh+=(MD4_LONG)(len>>29);     /* might cause compiler warning on 16-bit */
        c->Nl = l;

        n = c->num;
        if (n != 0) {
                p = (unsigned char *)c->data;

                if (len >= MD4_CBLOCK || len + n >= MD4_CBLOCK) {
                        memcpy (p + n, data, MD4_CBLOCK - n);
                        md4_block_data_order (c, p, 1);
                        n = MD4_CBLOCK - n;
                        data += n;
                        len -= n;
                        c->num = 0;
                        memset(p, 0, MD4_CBLOCK);       /* keep it zeroed */
                } else {
                        memcpy(p + n, data, len);
                        c->num += (unsigned int)len;
                        return 1;
                }
        }

        n = len / MD4_CBLOCK;
        if (n > 0) {
                md4_block_data_order(c, data, n);
                n    *= MD4_CBLOCK;
                data += n;
                len -= n;
        }

        if (len != 0) {
                p = (unsigned char *)c->data;
                c->num = (unsigned int)len;
                memcpy(p, data, len);
        }
        return 1;
}
LCRYPTO_ALIAS(MD4_Update);

void
MD4_Transform(MD4_CTX *c, const unsigned char *data)
{
        md4_block_data_order(c, data, 1);
}
LCRYPTO_ALIAS(MD4_Transform);

int
MD4_Final(unsigned char *md, MD4_CTX *c)
{
        unsigned char *p = (unsigned char *)c->data;
        size_t n = c->num;

        p[n] = 0x80; /* there is always room for one */
        n++;

        if (n > (MD4_CBLOCK - 8)) {
                memset(p + n, 0, MD4_CBLOCK - n);
                n = 0;
                md4_block_data_order(c, p, 1);
        }

        memset(p + n, 0, MD4_CBLOCK - 8 - n);
        c->data[MD4_LBLOCK - 2] = htole32(c->Nl);
        c->data[MD4_LBLOCK - 1] = htole32(c->Nh);

        md4_block_data_order(c, p, 1);
        c->num = 0;
        memset(p, 0, MD4_CBLOCK);

        crypto_store_htole32(&md[0 * 4], c->A);
        crypto_store_htole32(&md[1 * 4], c->B);
        crypto_store_htole32(&md[2 * 4], c->C);
        crypto_store_htole32(&md[3 * 4], c->D);

        return 1;
}
LCRYPTO_ALIAS(MD4_Final);

unsigned char *
MD4(const unsigned char *d, size_t n, unsigned char *md)
{
        MD4_CTX c;

        if (!MD4_Init(&c))
                return NULL;
        MD4_Update(&c, d, n);
        MD4_Final(md, &c);
        explicit_bzero(&c, sizeof(c));
        return (md);
}
LCRYPTO_ALIAS(MD4);