/*

 * Copyright 1995-2026 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 <time.h>

#include <sys/types.h>

#include "internal/cryptlib.h"

#include <openssl/bn.h>

#include <openssl/evp.h>

#include <openssl/x509.h>

#include <openssl/objects.h>

#include <openssl/buffer.h>

#include <openssl/core_names.h>

#include "crypto/asn1.h"

#include "crypto/evp.h"

#include "asn1_local.h"

#ifndef OPENSSL_NO_DEPRECATED_3_0

int ASN1_sign(i2d_of_void *i2d, X509_ALGOR *algor1, X509_ALGOR *algor2,

    ASN1_BIT_STRING *signature, char *data, EVP_PKEY *pkey,

    const EVP_MD *type)

{

    EVP_MD_CTX *ctx = EVP_MD_CTX_new();

    unsigned char *p, *buf_in = NULL, *buf_out = NULL;

    int i, inl = 0, outl = 0;

    size_t inll = 0, outll = 0;

    X509_ALGOR *a;

    if (ctx == NULL) {

        ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);

        goto err;

    }

    for (i = 0; i < 2; i++) {

        if (i == 0)

            a = algor1;

        else

            a = algor2;

        if (a == NULL)

            continue;

        if (type->pkey_type == NID_dsaWithSHA1) {

            /*

             * special case: RFC 3370 tells us to omit 'parameters' with

             * id-dsa-with-sha1

             */

            ASN1_TYPE_free(a->parameter);

            a->parameter = NULL;

        } else if ((a->parameter == NULL) || (a->parameter->type != V_ASN1_NULL)) {

            ASN1_TYPE_free(a->parameter);

            if ((a->parameter = ASN1_TYPE_new()) == NULL)

                goto err;

            a->parameter->type = V_ASN1_NULL;

        }

        ASN1_OBJECT_free(a->algorithm);

        a->algorithm = OBJ_nid2obj(type->pkey_type);

        if (a->algorithm == NULL) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_OBJECT_TYPE);

            goto err;

        }

        if (a->algorithm->length == 0) {

            ERR_raise(ERR_LIB_ASN1,

                ASN1_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);

            goto err;

        }

    }

    inl = i2d(data, NULL);

    if (inl <= 0) {

        ERR_raise(ERR_LIB_ASN1, ERR_R_INTERNAL_ERROR);

        goto err;

    }

    inll = (size_t)inl;

    buf_in = OPENSSL_malloc(inll);

    outll = outl = EVP_PKEY_get_size(pkey);

    buf_out = OPENSSL_malloc(outll);

    if (buf_in == NULL || buf_out == NULL) {

        outl = 0;

        goto err;

    }

    p = buf_in;

    i2d(data, &p);

    if (!EVP_SignInit_ex(ctx, type, NULL)

        || !EVP_SignUpdate(ctx, (unsigned char *)buf_in, inl)

        || !EVP_SignFinal(ctx, (unsigned char *)buf_out,

            (unsigned int *)&outl, pkey)) {

        outl = 0;

        ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);

        goto err;

    }

    ASN1_STRING_set0(signature, buf_out, outl);

    buf_out = NULL;

    /*

     * In the interests of compatibility, I'll make sure that the bit string

     * has a 'not-used bits' value of 0

     */

    ossl_asn1_bit_string_set_unused_bits(signature, 0);

err:

    EVP_MD_CTX_free(ctx);

    OPENSSL_clear_free((char *)buf_in, inll);

    OPENSSL_clear_free((char *)buf_out, outll);

    return outl;

}

#endif

int ASN1_item_sign(const ASN1_ITEM *it, X509_ALGOR *algor1, X509_ALGOR *algor2,

    ASN1_BIT_STRING *signature, const void *data,

    EVP_PKEY *pkey, const EVP_MD *md)

{

    return ASN1_item_sign_ex(it, algor1, algor2, signature, data, NULL, pkey,

        md, NULL, NULL);

}

int ASN1_item_sign_ex(const ASN1_ITEM *it, X509_ALGOR *algor1,

    X509_ALGOR *algor2, ASN1_BIT_STRING *signature,

    const void *data, const ASN1_OCTET_STRING *id,

    EVP_PKEY *pkey, const EVP_MD *md, OSSL_LIB_CTX *libctx,

    const char *propq)

{

    int rv = 0;

    EVP_MD_CTX *ctx = evp_md_ctx_new_ex(pkey, id, libctx, propq);

    if (ctx == NULL) {

        ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);

        return 0;

    }

    /* We can use the non _ex variant here since the pkey is already setup */

    if (!EVP_DigestSignInit(ctx, NULL, md, NULL, pkey))

        goto err;

    rv = ASN1_item_sign_ctx(it, algor1, algor2, signature, data, ctx);

err:

    EVP_PKEY_CTX_free(EVP_MD_CTX_get_pkey_ctx(ctx));

    EVP_MD_CTX_free(ctx);

    return rv;

}

static int replace_algor_contents_from_DER(X509_ALGOR *algor, const unsigned char *aid, size_t len)

{

    /* as a workaround for d2i_*() freeing its first argument, using NULL instead: */

    X509_ALGOR *alg = d2i_X509_ALGOR(NULL, &aid, (long)len);

    int ret;

    if (alg == NULL) {

        ERR_raise(ERR_LIB_ASN1, ASN1_R_DECODE_ERROR);

        return 0;

    }

    ret = X509_ALGOR_copy(algor, alg);

    X509_ALGOR_free(alg);

    return ret;

}

int ASN1_item_sign_ctx(const ASN1_ITEM *it, X509_ALGOR *algor1,

    X509_ALGOR *algor2, ASN1_BIT_STRING *signature,

    const void *data, EVP_MD_CTX *ctx)

{

    const EVP_MD *md;

    EVP_PKEY_CTX *pctx;

    EVP_PKEY *pkey;

    unsigned char *buf_in = NULL, *buf_out = NULL;

    size_t inl = 0, outl = 0, outll = 0;

    int signid, paramtype, buf_len = 0;

    int rv, pkey_id;

    md = EVP_MD_CTX_get0_md(ctx);

    pctx = EVP_MD_CTX_get_pkey_ctx(ctx);

    if (pctx == NULL) {

        ERR_raise(ERR_LIB_ASN1, ASN1_R_CONTEXT_NOT_INITIALISED);

        goto err;

    }

    pkey = EVP_PKEY_CTX_get0_pkey(pctx);

    if (pkey == NULL) {

        ERR_raise(ERR_LIB_ASN1, ASN1_R_CONTEXT_NOT_INITIALISED);

        goto err;

    }

    if (pkey->ameth == NULL) {

        OSSL_PARAM params[2];

        unsigned char aid[128];

        size_t aid_len = 0;

        if (!EVP_PKEY_CTX_IS_SIGNATURE_OP(pctx)) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_CONTEXT_NOT_INITIALISED);

            goto err;

        }

        params[0] = OSSL_PARAM_construct_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID,

            aid, sizeof(aid));

        params[1] = OSSL_PARAM_construct_end();

        if (EVP_PKEY_CTX_get_params(pctx, params) <= 0)

            goto err;

        if ((aid_len = params[0].return_size) == 0) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED);

            goto err;

        }

        if (algor1 != NULL && !replace_algor_contents_from_DER(algor1, aid, aid_len))

            goto err;

        if (algor2 != NULL && !replace_algor_contents_from_DER(algor2, aid, aid_len))

            goto err;

        rv = 3;

    } else if (pkey->ameth->item_sign) {

        rv = pkey->ameth->item_sign(ctx, it, data, algor1, algor2, signature);

        if (rv == 1)

            outl = signature->length;

        /*-

         * Return value meanings:

         * <=0: error.

         *   1: method does everything.

         *   2: carry on as normal.

         *   3: ASN1 method sets algorithm identifiers: just sign.

         */

        if (rv <= 0)

            ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);

        if (rv <= 1)

            goto err;

    } else {

        rv = 2;

    }

    if (rv == 2) {

        if (md == NULL) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_CONTEXT_NOT_INITIALISED);

            goto err;

        }

        pkey_id =

#ifndef OPENSSL_NO_SM2

            EVP_PKEY_get_id(pkey) == NID_sm2 ? NID_sm2 :

#endif

                                             pkey->ameth->pkey_id;

        if (!OBJ_find_sigid_by_algs(&signid, EVP_MD_nid(md), pkey_id)) {

            ERR_raise(ERR_LIB_ASN1, ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED);

            goto err;

        }

        paramtype = pkey->ameth->pkey_flags & ASN1_PKEY_SIGPARAM_NULL ? V_ASN1_NULL : V_ASN1_UNDEF;

        if (algor1 != NULL

            && !X509_ALGOR_set0(algor1, OBJ_nid2obj(signid), paramtype, NULL))

            goto err;

        if (algor2 != NULL

            && !X509_ALGOR_set0(algor2, OBJ_nid2obj(signid), paramtype, NULL))

            goto err;

    }

    buf_len = ASN1_item_i2d(data, &buf_in, it);

    if (buf_len <= 0) {

        outl = 0;

        ERR_raise(ERR_LIB_ASN1, ERR_R_INTERNAL_ERROR);

        goto err;

    }

    inl = buf_len;

    if (!EVP_DigestSign(ctx, NULL, &outll, buf_in, inl)) {

        outl = 0;

        ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);

        goto err;

    }

    outl = outll;

    buf_out = OPENSSL_malloc(outll);

    if (buf_in == NULL || buf_out == NULL) {

        outl = 0;

        goto err;

    }

    if (!EVP_DigestSign(ctx, buf_out, &outl, buf_in, inl)) {

        outl = 0;

        ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);

        goto err;

    }

    /* Only a sequence item carries a cached encoding */

    if ((it->itype == ASN1_ITYPE_SEQUENCE

            || it->itype == ASN1_ITYPE_NDEF_SEQUENCE)

        && !ossl_asn1_enc_save((ASN1_VALUE **)&data, buf_in, buf_len, it)) {

        outl = 0;

        ERR_raise(ERR_LIB_ASN1, ERR_R_ASN1_LIB);

        goto err;

    }

    ASN1_STRING_set0(signature, buf_out, (int)outl);

    buf_out = NULL;

    /*

     * In the interests of compatibility, I'll make sure that the bit string

     * has a 'not-used bits' value of 0

     */

    ossl_asn1_bit_string_set_unused_bits(signature, 0);

err:

    OPENSSL_clear_free((char *)buf_in, inl);

    OPENSSL_clear_free((char *)buf_out, outll);

    return (int)outl;

}