/* $OpenBSD: p12_key.c,v 1.37 2025/05/10 05:54:38 tb Exp $ */
/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
 * project 1999.
 */
/* ====================================================================
 * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
 *
 * 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 above 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 acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED 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 OpenSSL PROJECT OR
 * ITS 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.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

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

#include <openssl/bn.h>
#include <openssl/pkcs12.h>

#include "err_local.h"
#include "evp_local.h"
#include "pkcs12_local.h"

/* PKCS12 compatible key/IV generation */
#ifndef min
#define min(a,b) ((a) < (b) ? (a) : (b))
#endif

int
PKCS12_key_gen_asc(const char *pass, int passlen, unsigned char *salt,
    int saltlen, int id, int iter, int n, unsigned char *out,
    const EVP_MD *md_type)
{
        int ret;
        unsigned char *unipass;
        int uniplen;

        if (!pass) {
                unipass = NULL;
                uniplen = 0;
        } else if (!OPENSSL_asc2uni(pass, passlen, &unipass, &uniplen)) {
                PKCS12error(ERR_R_MALLOC_FAILURE);
                return 0;
        }
        ret = PKCS12_key_gen_uni(unipass, uniplen, salt, saltlen,
            id, iter, n, out, md_type);
        if (ret <= 0)
                return 0;
        freezero(unipass, uniplen);
        return ret;
}

int
PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt,
    int saltlen, int id, int iter, int n, unsigned char *out,
    const EVP_MD *md_type)
{
        EVP_MD_CTX *ctx = NULL;
        unsigned char *B = NULL, *D = NULL, *I = NULL, *Ai = NULL;
        unsigned char *p;
        int Slen, Plen, Ilen;
        int i, j, u, v;
        int ret = 0;

        if ((ctx = EVP_MD_CTX_new()) == NULL)
                goto err;

        if ((v = EVP_MD_block_size(md_type)) <= 0)
                goto err;
        if ((u = EVP_MD_size(md_type)) <= 0)
                goto err;

        if ((D = malloc(v)) == NULL)
                goto err;
        if ((Ai = malloc(u)) == NULL)
                goto err;
        if ((B = malloc(v + 1)) == NULL)
                goto err;

        Slen = v * ((saltlen + v - 1) / v);

        Plen = 0;
        if (passlen)
                Plen = v * ((passlen + v - 1) / v);

        Ilen = Slen + Plen;

        if ((I = malloc(Ilen)) == NULL)
                goto err;

        for (i = 0; i < v; i++)
                D[i] = id;

        p = I;
        for (i = 0; i < Slen; i++)
                *p++ = salt[i % saltlen];
        for (i = 0; i < Plen; i++)
                *p++ = pass[i % passlen];

        for (;;) {
                if (!EVP_DigestInit_ex(ctx, md_type, NULL))
                        goto err;
                if (!EVP_DigestUpdate(ctx, D, v))
                        goto err;
                if (!EVP_DigestUpdate(ctx, I, Ilen))
                        goto err;
                if (!EVP_DigestFinal_ex(ctx, Ai, NULL))
                        goto err;
                for (j = 1; j < iter; j++) {
                        if (!EVP_DigestInit_ex(ctx, md_type, NULL))
                                goto err;
                        if (!EVP_DigestUpdate(ctx, Ai, u))
                                goto err;
                        if (!EVP_DigestFinal_ex(ctx, Ai, NULL))
                                goto err;
                }
                memcpy(out, Ai, min(n, u));
                if (u >= n) {
                        ret = 1;
                        goto end;
                }
                n -= u;
                out += u;
                for (j = 0; j < v; j++)
                        B[j] = Ai[j % u];

                for (j = 0; j < Ilen; j += v) {
                        uint16_t c = 1;
                        int k;

                        /* Work out I[j] = I[j] + B + 1. */
                        for (k = v - 1; k >= 0; k--) {
                                c += I[j + k] + B[k];
                                I[j + k] = (unsigned char)c;
                                c >>= 8;
                        }
                }
        }

 err:
        PKCS12error(ERR_R_MALLOC_FAILURE);

 end:
        free(Ai);
        free(B);
        free(D);
        free(I);
        EVP_MD_CTX_free(ctx);

        return ret;
}
LCRYPTO_ALIAS(PKCS12_key_gen_uni);