/*

 * Copyright 1999-2025 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 <stdio.h>

#include <stdlib.h>

#include "internal/cryptlib.h"

#include <openssl/x509.h>

#include <openssl/evp.h>

#include <openssl/kdf.h>

#include <openssl/hmac.h>

#include <openssl/trace.h>

#include <openssl/core_names.h>

#include "crypto/evp.h"

#include "evp_local.h"

int ossl_pkcs5_pbkdf2_hmac_ex(const char *pass, int passlen,

    const unsigned char *salt, int saltlen, int iter,

    const EVP_MD *digest, int keylen, unsigned char *out,

    OSSL_LIB_CTX *libctx, const char *propq)

{

    const char *empty = "";

    int rv = 1, mode = 1;

    EVP_KDF *kdf;

    EVP_KDF_CTX *kctx;

    const char *mdname = EVP_MD_get0_name(digest);

    OSSL_PARAM params[6], *p = params;

    /* Keep documented behaviour. */

    if (pass == NULL) {

        pass = empty;

        passlen = 0;

    } else if (passlen == -1) {

        passlen = (int)strlen(pass);

    }

    if (salt == NULL && saltlen == 0)

        salt = (unsigned char *)empty;

    kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_PBKDF2, propq);

    if (kdf == NULL)

        return 0;

    kctx = EVP_KDF_CTX_new(kdf);

    EVP_KDF_free(kdf);

    if (kctx == NULL)

        return 0;

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PASSWORD,

        (char *)pass, (size_t)passlen);

    *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_PKCS5, &mode);

    *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT,

        (unsigned char *)salt, saltlen);

    *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_ITER, &iter);

    *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,

        (char *)mdname, 0);

    *p = OSSL_PARAM_construct_end();

    if (EVP_KDF_derive(kctx, out, keylen, params) != 1)

        rv = 0;

    EVP_KDF_CTX_free(kctx);

    OSSL_TRACE_BEGIN(PKCS5V2)

    {

        BIO_printf(trc_out, "Password:\n");

        BIO_hex_string(trc_out,

            0, passlen, pass, passlen);

        BIO_printf(trc_out, "\n");

        BIO_printf(trc_out, "Salt:\n");

        BIO_hex_string(trc_out,

            0, saltlen, salt, saltlen);

        BIO_printf(trc_out, "\n");

        BIO_printf(trc_out, "Iteration count %d\n", iter);

        BIO_printf(trc_out, "Key:\n");

        BIO_hex_string(trc_out,

            0, keylen, out, keylen);

        BIO_printf(trc_out, "\n");

    }

    OSSL_TRACE_END(PKCS5V2);

    return rv;

}

int PKCS5_PBKDF2_HMAC(const char *pass, int passlen, const unsigned char *salt,

    int saltlen, int iter, const EVP_MD *digest, int keylen,

    unsigned char *out)

{

    return ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, iter, digest,

        keylen, out, NULL, NULL);

}

int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,

    const unsigned char *salt, int saltlen, int iter,

    int keylen, unsigned char *out)

{

    EVP_MD *digest;

    int r = 0;

    if ((digest = EVP_MD_fetch(NULL, SN_sha1, NULL)) != NULL)

        r = ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, iter,

            digest, keylen, out, NULL, NULL);

    EVP_MD_free(digest);

    return r;

}

/*

 * Now the key derivation function itself. This is a bit evil because it has

 * to check the ASN1 parameters are valid: and there are quite a few of

 * them...

 */

int PKCS5_v2_PBE_keyivgen_ex(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,

    ASN1_TYPE *param, const EVP_CIPHER *c,

    const EVP_MD *md, int en_de,

    OSSL_LIB_CTX *libctx, const char *propq)

{

    PBE2PARAM *pbe2 = NULL;

    char ciph_name[80];

    EVP_CIPHER *cipher = NULL;

    EVP_PBE_KEYGEN_EX *kdf;

    int rv = 0;

    pbe2 = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBE2PARAM), param);

    if (pbe2 == NULL) {

        ERR_raise(ERR_LIB_EVP, EVP_R_DECODE_ERROR);

        goto err;

    }

    /* See if we recognise the key derivation function */

    if (!EVP_PBE_find_ex(EVP_PBE_TYPE_KDF, OBJ_obj2nid(pbe2->keyfunc->algorithm),

            NULL, NULL, NULL, &kdf)) {

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);

        goto err;

    }

    /*

     * lets see if we recognise the encryption algorithm.

     */

    if (OBJ_obj2txt(ciph_name, sizeof(ciph_name), pbe2->encryption->algorithm, 0) <= 0) {

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_CIPHER);

        goto err;

    }

    cipher = EVP_CIPHER_fetch(libctx, ciph_name, propq);

    if (cipher == NULL) {

        (void)ERR_clear_last_mark();

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_CIPHER);

        goto err;

    }

    (void)ERR_pop_to_mark();

    /* Fixup cipher based on AlgorithmIdentifier */

    if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de))

        goto err;

    if (EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) <= 0) {

        ERR_raise(ERR_LIB_EVP, EVP_R_CIPHER_PARAMETER_ERROR);

        goto err;

    }

    rv = kdf(ctx, pass, passlen, pbe2->keyfunc->parameter, NULL, NULL, en_de, libctx, propq);

err:

    EVP_CIPHER_free(cipher);

    PBE2PARAM_free(pbe2);

    return rv;

}

int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,

    ASN1_TYPE *param, const EVP_CIPHER *c,

    const EVP_MD *md, int en_de)

{

    return PKCS5_v2_PBE_keyivgen_ex(ctx, pass, passlen, param, c, md, en_de, NULL, NULL);

}

int PKCS5_v2_PBKDF2_keyivgen_ex(EVP_CIPHER_CTX *ctx, const char *pass,

    int passlen, ASN1_TYPE *param,

    const EVP_CIPHER *c, const EVP_MD *md, int en_de,

    OSSL_LIB_CTX *libctx, const char *propq)

{

    unsigned char *salt, key[EVP_MAX_KEY_LENGTH];

    int saltlen, iter, t;

    int rv = 0;

    unsigned int keylen = 0;

    int prf_nid, hmac_md_nid;

    PBKDF2PARAM *kdf = NULL;

    EVP_MD *prfmd = NULL;

    if (EVP_CIPHER_CTX_get0_cipher(ctx) == NULL) {

        ERR_raise(ERR_LIB_EVP, EVP_R_NO_CIPHER_SET);

        goto err;

    }

    keylen = EVP_CIPHER_CTX_get_key_length(ctx);

    OPENSSL_assert(keylen <= sizeof(key));

    /* Decode parameter */

    kdf = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBKDF2PARAM), param);

    if (kdf == NULL) {

        ERR_raise(ERR_LIB_EVP, EVP_R_DECODE_ERROR);

        goto err;

    }

    t = EVP_CIPHER_CTX_get_key_length(ctx);

    if (t < 0) {

        ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_KEY_LENGTH);

        goto err;

    }

    keylen = t;

    /* Now check the parameters of the kdf */

    if (kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != (int)keylen)) {

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_KEYLENGTH);

        goto err;

    }

    if (kdf->prf)

        prf_nid = OBJ_obj2nid(kdf->prf->algorithm);

    else

        prf_nid = NID_hmacWithSHA1;

    if (!EVP_PBE_find(EVP_PBE_TYPE_PRF, prf_nid, NULL, &hmac_md_nid, 0)) {

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_PRF);

        goto err;

    }

    prfmd = EVP_MD_fetch(libctx, OBJ_nid2sn(hmac_md_nid), propq);

    if (prfmd == NULL) {

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_PRF);

        goto err;

    }

    if (kdf->salt->type != V_ASN1_OCTET_STRING) {

        ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_SALT_TYPE);

        goto err;

    }

    /* it seems that its all OK */

    salt = kdf->salt->value.octet_string->data;

    saltlen = kdf->salt->value.octet_string->length;

    iter = ASN1_INTEGER_get(kdf->iter);

    if (!ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, iter, prfmd,

            keylen, key, libctx, propq))

        goto err;

    rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);

err:

    OPENSSL_cleanse(key, keylen);

    PBKDF2PARAM_free(kdf);

    EVP_MD_free(prfmd);

    return rv;

}

int PKCS5_v2_PBKDF2_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass,

    int passlen, ASN1_TYPE *param,

    const EVP_CIPHER *c, const EVP_MD *md, int en_de)

{

    return PKCS5_v2_PBKDF2_keyivgen_ex(ctx, pass, passlen, param, c, md, en_de,

        NULL, NULL);

}