/*

 * Copyright 2006-2025 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (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 "internal/cryptlib.h"

#include <stdio.h>

#include <openssl/asn1t.h>

#include <openssl/x509.h>

#include "crypto/asn1.h"

#include "crypto/evp.h"

#include "standard_methods.h"

typedef int sk_cmp_fn_type(const char *const *a, const char *const *b);

DECLARE_OBJ_BSEARCH_CMP_FN(const EVP_PKEY_ASN1_METHOD *,

    const EVP_PKEY_ASN1_METHOD *, ameth);

static int ameth_cmp(const EVP_PKEY_ASN1_METHOD *const *a,

    const EVP_PKEY_ASN1_METHOD *const *b)

{

    return ((*a)->pkey_id - (*b)->pkey_id);

}

IMPLEMENT_OBJ_BSEARCH_CMP_FN(const EVP_PKEY_ASN1_METHOD *,

    const EVP_PKEY_ASN1_METHOD *, ameth);

int evp_pkey_asn1_get_count(void)

{

    int num = OSSL_NELEM(standard_methods);

    return num;

}

const EVP_PKEY_ASN1_METHOD *evp_pkey_asn1_get0(int idx)

{

    int num = OSSL_NELEM(standard_methods);

    if (idx < 0 || idx >= num)

        return NULL;

    return standard_methods[idx];

}

static const EVP_PKEY_ASN1_METHOD *pkey_asn1_find(int type)

{

    EVP_PKEY_ASN1_METHOD tmp;

    const EVP_PKEY_ASN1_METHOD *t = &tmp, **ret;

    tmp.pkey_id = type;

    ret = OBJ_bsearch_ameth(&t, standard_methods, OSSL_NELEM(standard_methods));

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

        return NULL;

    return *ret;

}

/*

 * Return ASN1 method for desired `type`, returns NULL if no method is found for

 * `type`. If pe is not NULL, the function will set *pe to NULL to indicate no

 * engine is used.

 */

const EVP_PKEY_ASN1_METHOD *evp_pkey_asn1_find(int type)

{

    const EVP_PKEY_ASN1_METHOD *t;

    for (;;) {

        t = pkey_asn1_find(type);

        if (!t || !(t->pkey_flags & ASN1_PKEY_ALIAS))

            break;

        type = t->pkey_base_id;

    }

    return t;

}

const EVP_PKEY_ASN1_METHOD *evp_pkey_asn1_find_str(const char *str, int len)

{

    int i;

    const EVP_PKEY_ASN1_METHOD *ameth = NULL;

    if (len == -1)

        len = (int)strlen(str);

    for (i = evp_pkey_asn1_get_count(); i-- > 0;) {

        ameth = evp_pkey_asn1_get0(i);

        if (ameth->pkey_flags & ASN1_PKEY_ALIAS)

            continue;

        if ((int)strlen(ameth->pem_str) == len

            && OPENSSL_strncasecmp(ameth->pem_str, str, len) == 0)

            return ameth;

    }

    return NULL;

}

int evp_pkey_asn1_get0_info(int *ppkey_id, int *ppkey_base_id,

    int *ppkey_flags, const char **pinfo,

    const char **ppem_str,

    const EVP_PKEY_ASN1_METHOD *ameth)

{

    if (!ameth)

        return 0;

    if (ppkey_id)

        *ppkey_id = ameth->pkey_id;

    if (ppkey_base_id)

        *ppkey_base_id = ameth->pkey_base_id;

    if (ppkey_flags)

        *ppkey_flags = ameth->pkey_flags;

    if (pinfo)

        *pinfo = ameth->info;

    if (ppem_str)

        *ppem_str = ameth->pem_str;

    return 1;

}

const EVP_PKEY_ASN1_METHOD *evp_pkey_get0_asn1(const EVP_PKEY *pkey)

{

    return pkey->ameth;

}