/*

 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (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

 */

#include <stdio.h>

#include "internal/cryptlib.h"

#include <openssl/bn.h>

#include <openssl/evp.h>

#include <openssl/objects.h>

#include <openssl/engine.h>

#include <openssl/x509.h>

#include <openssl/asn1.h>

#include "crypto/asn1.h"

#include "crypto/evp.h"

EVP_PKEY *d2i_PrivateKey(int type, EVP_PKEY **a, const unsigned char **pp,

                         long length)

{

    EVP_PKEY *ret;

    const unsigned char *p = *pp;

    if ((a == NULL) || (*a == NULL)) {

        if ((ret = EVP_PKEY_new()) == NULL) {

            ASN1err(ASN1_F_D2I_PRIVATEKEY, ERR_R_EVP_LIB);

            return NULL;

        }

    } else {

        ret = *a;

#ifndef OPENSSL_NO_ENGINE

        ENGINE_finish(ret->engine);

        ret->engine = NULL;

#endif

    }

    if (!EVP_PKEY_set_type(ret, type)) {

        ASN1err(ASN1_F_D2I_PRIVATEKEY, ASN1_R_UNKNOWN_PUBLIC_KEY_TYPE);

        goto err;

    }

    if (!ret->ameth->old_priv_decode ||

        !ret->ameth->old_priv_decode(ret, &p, length)) {

        if (ret->ameth->priv_decode) {

            EVP_PKEY *tmp;

            PKCS8_PRIV_KEY_INFO *p8 = NULL;

            p8 = d2i_PKCS8_PRIV_KEY_INFO(NULL, &p, length);

            if (!p8)

                goto err;

            tmp = EVP_PKCS82PKEY(p8);

            PKCS8_PRIV_KEY_INFO_free(p8);

            if (tmp == NULL)

                goto err;

            EVP_PKEY_free(ret);

            ret = tmp;

            if (EVP_PKEY_type(type) != EVP_PKEY_base_id(ret))

                goto err;

        } else {

            ASN1err(ASN1_F_D2I_PRIVATEKEY, ERR_R_ASN1_LIB);

            goto err;

        }

    }

    *pp = p;

    if (a != NULL)

        (*a) = ret;

    return ret;

 err:

    if (a == NULL || *a != ret)

        EVP_PKEY_free(ret);

    return NULL;

}

/*

 * This works like d2i_PrivateKey() except it automatically works out the

 * type

 */

static EVP_PKEY *key_as_pkcs8(const unsigned char **pp, long length, int *carry_on)

{

    const unsigned char *p = *pp;

    PKCS8_PRIV_KEY_INFO *p8 = d2i_PKCS8_PRIV_KEY_INFO(NULL, &p, length);

    EVP_PKEY *ret;

    if (p8 == NULL)

        return NULL;

    ret = EVP_PKCS82PKEY(p8);

    if (ret == NULL)

        *carry_on = 0;

    PKCS8_PRIV_KEY_INFO_free(p8);

    if (ret != NULL)

        *pp = p;

    return ret;

}

EVP_PKEY *d2i_AutoPrivateKey(EVP_PKEY **a, const unsigned char **pp,

                             long length)

{

    STACK_OF(ASN1_TYPE) *inkey;

    const unsigned char *p;

    int keytype;

    EVP_PKEY *ret = NULL;

    int carry_on = 1;

    ERR_set_mark();

    ret = key_as_pkcs8(pp, length, &carry_on);

    if (ret != NULL) {

        ERR_clear_last_mark();

        if (a != NULL)

            *a = ret;

        return ret;

    }

    if (carry_on == 0) {

        ERR_clear_last_mark();

        ASN1err(ASN1_F_D2I_AUTOPRIVATEKEY,

                ASN1_R_UNSUPPORTED_PUBLIC_KEY_TYPE);

        return NULL;

    }

    p = *pp;

    /*

     * Dirty trick: read in the ASN1 data into a STACK_OF(ASN1_TYPE): by

     * analyzing it we can determine the passed structure: this assumes the

     * input is surrounded by an ASN1 SEQUENCE.

     */

    inkey = d2i_ASN1_SEQUENCE_ANY(NULL, &p, length);

    p = *pp;

    /*

     * Since we only need to discern "traditional format" RSA and DSA keys we

     * can just count the elements.

     */

    if (sk_ASN1_TYPE_num(inkey) == 6)

        keytype = EVP_PKEY_DSA;

    else if (sk_ASN1_TYPE_num(inkey) == 4)

        keytype = EVP_PKEY_EC;

    else

        keytype = EVP_PKEY_RSA;

    sk_ASN1_TYPE_pop_free(inkey, ASN1_TYPE_free);

    ret = d2i_PrivateKey(keytype, a, pp, length);

    if (ret != NULL)

        ERR_pop_to_mark();

    else

        ERR_clear_last_mark();

    return ret;

}