asn_pack.c

/*
 * Copyright 1999-2023 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 "internal/cryptlib.h"
#include <openssl/asn1.h>

/* ASN1 packing and unpacking functions */

ASN1_STRING *ASN1_item_pack(void *obj, const ASN1_ITEM *it, ASN1_STRING **oct)
{
    ASN1_STRING *octmp;

    if (oct == NULL || *oct == NULL) {
        if ((octmp = ASN1_STRING_new()) == NULL) {
            ERR_raise(ERR_LIB_ASN1, ERR_R_ASN1_LIB);
            return NULL;
        }
    } else {
        octmp = *oct;
    }

    ASN1_STRING_set0(octmp, NULL, 0);

    if ((octmp->length = ASN1_item_i2d(obj, &octmp->data, it)) <= 0) {
        ERR_raise(ERR_LIB_ASN1, ASN1_R_ENCODE_ERROR);
        goto err;
    }
    if (octmp->data == NULL) {
        ERR_raise(ERR_LIB_ASN1, ERR_R_ASN1_LIB);
        goto err;
    }

    if (oct != NULL && *oct == NULL)
        *oct = octmp;

    return octmp;
 err:
    if (oct == NULL || *oct == NULL)
        ASN1_STRING_free(octmp);
    return NULL;
}

/* Extract an ASN1 object from an ASN1_STRING */

void *ASN1_item_unpack(const ASN1_STRING *oct, const ASN1_ITEM *it)
{
    const unsigned char *p;
    void *ret;

    p = oct->data;
    if ((ret = ASN1_item_d2i(NULL, &p, oct->length, it)) == NULL)
        ERR_raise(ERR_LIB_ASN1, ASN1_R_DECODE_ERROR);
    return ret;
}

void *ASN1_item_unpack_ex(const ASN1_STRING *oct, const ASN1_ITEM *it,
                          OSSL_LIB_CTX *libctx, const char *propq)
{
    const unsigned char *p;
    void *ret;

    p = oct->data;
    if ((ret = ASN1_item_d2i_ex(NULL, &p, oct->length, it,\
                                libctx, propq)) == NULL)
        ERR_raise(ERR_LIB_ASN1, ASN1_R_DECODE_ERROR);
    return ret;
}