/* crypto/evp/bio_md.c */

/* 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 <errno.h>

#include "cryptlib.h"

#include <openssl/buffer.h>

#include <openssl/evp.h>

/*

 * BIO_put and BIO_get both add to the digest, BIO_gets returns the digest

 */

static int md_write(BIO *h, char const *buf, int num);

static int md_read(BIO *h, char *buf, int size);

/*

 * static int md_puts(BIO *h, const char *str);

 */

static int md_gets(BIO *h, char *str, int size);

static long md_ctrl(BIO *h, int cmd, long arg1, void *arg2);

static int md_new(BIO *h);

static int md_free(BIO *data);

static long md_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);

static BIO_METHOD methods_md = {

    BIO_TYPE_MD, "message digest",

    md_write,

    md_read,

    NULL,                       /* md_puts, */

    md_gets,

    md_ctrl,

    md_new,

    md_free,

    md_callback_ctrl,

};

BIO_METHOD *BIO_f_md(void)

{

    return (&methods_md);

}

static int md_new(BIO *bi)

{

    EVP_MD_CTX *ctx;

    ctx = EVP_MD_CTX_create();

    if (ctx == NULL)

        return (0);

    bi->init = 0;

    bi->ptr = (char *)ctx;

    bi->flags = 0;

    return (1);

}

static int md_free(BIO *a)

{

    if (a == NULL)

        return (0);

    EVP_MD_CTX_destroy(a->ptr);

    a->ptr = NULL;

    a->init = 0;

    a->flags = 0;

    return (1);

}

static int md_read(BIO *b, char *out, int outl)

{

    int ret = 0;

    EVP_MD_CTX *ctx;

    if (out == NULL)

        return (0);

    ctx = b->ptr;

    if ((ctx == NULL) || (b->next_bio == NULL))

        return (0);

    ret = BIO_read(b->next_bio, out, outl);

    if (b->init) {

        if (ret > 0) {

            if (EVP_DigestUpdate(ctx, (unsigned char *)out,

                                 (unsigned int)ret) <= 0)

                return (-1);

        }

    }

    BIO_clear_retry_flags(b);

    BIO_copy_next_retry(b);

    return (ret);

}

static int md_write(BIO *b, const char *in, int inl)

{

    int ret = 0;

    EVP_MD_CTX *ctx;

    if ((in == NULL) || (inl <= 0))

        return (0);

    ctx = b->ptr;

    if ((ctx != NULL) && (b->next_bio != NULL))

        ret = BIO_write(b->next_bio, in, inl);

    if (b->init) {

        if (ret > 0) {

            if (!EVP_DigestUpdate(ctx, (const unsigned char *)in,

                                  (unsigned int)ret)) {

                BIO_clear_retry_flags(b);

                return 0;

            }

        }

    }

    if (b->next_bio != NULL) {

        BIO_clear_retry_flags(b);

        BIO_copy_next_retry(b);

    }

    return (ret);

}

static long md_ctrl(BIO *b, int cmd, long num, void *ptr)

{

    EVP_MD_CTX *ctx, *dctx, **pctx;

    const EVP_MD **ppmd;

    EVP_MD *md;

    long ret = 1;

    BIO *dbio;

    ctx = b->ptr;

    switch (cmd) {

    case BIO_CTRL_RESET:

        if (b->init)

            ret = EVP_DigestInit_ex(ctx, ctx->digest, NULL);

        else

            ret = 0;

        if (ret > 0)

            ret = BIO_ctrl(b->next_bio, cmd, num, ptr);

        break;

    case BIO_C_GET_MD:

        if (b->init) {

            ppmd = ptr;

            *ppmd = ctx->digest;

        } else

            ret = 0;

        break;

    case BIO_C_GET_MD_CTX:

        pctx = ptr;

        *pctx = ctx;

        b->init = 1;

        break;

    case BIO_C_SET_MD_CTX:

        if (b->init)

            b->ptr = ptr;

        else

            ret = 0;

        break;

    case BIO_C_DO_STATE_MACHINE:

        BIO_clear_retry_flags(b);

        ret = BIO_ctrl(b->next_bio, cmd, num, ptr);

        BIO_copy_next_retry(b);

        break;

    case BIO_C_SET_MD:

        md = ptr;

        ret = EVP_DigestInit_ex(ctx, md, NULL);

        if (ret > 0)

            b->init = 1;

        break;

    case BIO_CTRL_DUP:

        dbio = ptr;

        dctx = dbio->ptr;

        if (!EVP_MD_CTX_copy_ex(dctx, ctx))

            return 0;

        b->init = 1;

        break;

    default:

        ret = BIO_ctrl(b->next_bio, cmd, num, ptr);

        break;

    }

    return (ret);

}

static long md_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)

{

    long ret = 1;

    if (b->next_bio == NULL)

        return (0);

    switch (cmd) {

    default:

        ret = BIO_callback_ctrl(b->next_bio, cmd, fp);

        break;

    }

    return (ret);

}

static int md_gets(BIO *bp, char *buf, int size)

{

    EVP_MD_CTX *ctx;

    unsigned int ret;

    ctx = bp->ptr;

    if (size < ctx->digest->md_size)

        return (0);

    if (EVP_DigestFinal_ex(ctx, (unsigned char *)buf, &ret) <= 0)

        return -1;

    return ((int)ret);

}

/*-

static int md_puts(bp,str)

BIO *bp;

char *str;

        {

        return(-1);

        }

*/