/* m_sigver.c */

/*

 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project

 * 2006.

 */

/* ====================================================================

 * Copyright (c) 2006,2007 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 "cryptlib.h"

#include <openssl/evp.h>

#include <openssl/objects.h>

#include <openssl/x509.h>

#include "evp_locl.h"

static int do_sigver_init(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,

                          const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey,

                          int ver)

{

    if (ctx->pctx == NULL)

        ctx->pctx = EVP_PKEY_CTX_new(pkey, e);

    if (ctx->pctx == NULL)

        return 0;

    if (!(ctx->pctx->pmeth->flags & EVP_PKEY_FLAG_SIGCTX_CUSTOM)) {

        if (type == NULL) {

            int def_nid;

            if (EVP_PKEY_get_default_digest_nid(pkey, &def_nid) > 0)

                type = EVP_get_digestbynid(def_nid);

        }

        if (type == NULL) {

            EVPerr(EVP_F_DO_SIGVER_INIT, EVP_R_NO_DEFAULT_DIGEST);

            return 0;

        }

    }

    if (ver) {

        if (ctx->pctx->pmeth->verifyctx_init) {

            if (ctx->pctx->pmeth->verifyctx_init(ctx->pctx, ctx) <= 0)

                return 0;

            ctx->pctx->operation = EVP_PKEY_OP_VERIFYCTX;

        } else if (EVP_PKEY_verify_init(ctx->pctx) <= 0)

            return 0;

    } else {

        if (ctx->pctx->pmeth->signctx_init) {

            if (ctx->pctx->pmeth->signctx_init(ctx->pctx, ctx) <= 0)

                return 0;

            ctx->pctx->operation = EVP_PKEY_OP_SIGNCTX;

        } else if (EVP_PKEY_sign_init(ctx->pctx) <= 0)

            return 0;

    }

    if (EVP_PKEY_CTX_set_signature_md(ctx->pctx, type) <= 0)

        return 0;

    if (pctx)

        *pctx = ctx->pctx;

    if (ctx->pctx->pmeth->flags & EVP_PKEY_FLAG_SIGCTX_CUSTOM)

        return 1;

    if (!EVP_DigestInit_ex(ctx, type, e))

        return 0;

    return 1;

}

int EVP_DigestSignInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,

                       const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey)

{

    return do_sigver_init(ctx, pctx, type, e, pkey, 0);

}

int EVP_DigestVerifyInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,

                         const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey)

{

    return do_sigver_init(ctx, pctx, type, e, pkey, 1);

}

int EVP_DigestSignFinal(EVP_MD_CTX *ctx, unsigned char *sigret,

                        size_t *siglen)

{

    int sctx, r = 0;

    EVP_PKEY_CTX *pctx = ctx->pctx;

    if (pctx->pmeth->flags & EVP_PKEY_FLAG_SIGCTX_CUSTOM) {

        EVP_PKEY_CTX *dctx;

        if (!sigret)

            return pctx->pmeth->signctx(pctx, sigret, siglen, ctx);

        dctx = EVP_PKEY_CTX_dup(ctx->pctx);

        if (!dctx)

            return 0;

        r = dctx->pmeth->signctx(dctx, sigret, siglen, ctx);

        EVP_PKEY_CTX_free(dctx);

        return r;

    }

    if (pctx->pmeth->signctx)

        sctx = 1;

    else

        sctx = 0;

    if (sigret) {

        EVP_MD_CTX tmp_ctx;

        unsigned char md[EVP_MAX_MD_SIZE];

        unsigned int mdlen;

        EVP_MD_CTX_init(&tmp_ctx);

        if (!EVP_MD_CTX_copy_ex(&tmp_ctx, ctx))

            return 0;

        if (sctx)

            r = tmp_ctx.pctx->pmeth->signctx(tmp_ctx.pctx,

                                             sigret, siglen, &tmp_ctx);

        else

            r = EVP_DigestFinal_ex(&tmp_ctx, md, &mdlen);

        EVP_MD_CTX_cleanup(&tmp_ctx);

        if (sctx || !r)

            return r;

        if (EVP_PKEY_sign(ctx->pctx, sigret, siglen, md, mdlen) <= 0)

            return 0;

    } else {

        if (sctx) {

            if (pctx->pmeth->signctx(pctx, sigret, siglen, ctx) <= 0)

                return 0;

        } else {

            int s = EVP_MD_size(ctx->digest);

            if (s < 0 || EVP_PKEY_sign(pctx, sigret, siglen, NULL, s) <= 0)

                return 0;

        }

    }

    return 1;

}

int EVP_DigestVerifyFinal(EVP_MD_CTX *ctx, const unsigned char *sig,

                          size_t siglen)

{

    EVP_MD_CTX tmp_ctx;

    unsigned char md[EVP_MAX_MD_SIZE];

    int r;

    unsigned int mdlen;

    int vctx;

    if (ctx->pctx->pmeth->verifyctx)

        vctx = 1;

    else

        vctx = 0;

    EVP_MD_CTX_init(&tmp_ctx);

    if (!EVP_MD_CTX_copy_ex(&tmp_ctx, ctx))

        return -1;

    if (vctx) {

        r = tmp_ctx.pctx->pmeth->verifyctx(tmp_ctx.pctx,

                                           sig, siglen, &tmp_ctx);

    } else

        r = EVP_DigestFinal_ex(&tmp_ctx, md, &mdlen);

    EVP_MD_CTX_cleanup(&tmp_ctx);

    if (vctx || !r)

        return r;

    return EVP_PKEY_verify(ctx->pctx, sig, siglen, md, mdlen);

}