---
name: "X509_ACERT_get0_holder_baseCertId"
section: "3ssl"
platform: "linux"
package: "openssl"
version: "3.6.5-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/X509_ACERT_get0_holder_baseCertId"
---

# X509\_ACERT\_get0\_holder\_baseCertId(3ssl)

get and set Attribute Certificate holder fields

## NAME

X509\_ACERT\_get0\_holder\_baseCertId, X509\_ACERT\_get0\_holder\_digest, X509\_ACERT\_get0\_holder\_entityName, X509\_ACERT\_set0\_holder\_baseCertId, X509\_ACERT\_set0\_holder\_digest, X509\_ACERT\_set0\_holder\_entityName, OSSL\_ISSUER\_SERIAL\_get0\_issuer, OSSL\_ISSUER\_SERIAL\_get0\_issuerUID, OSSL\_ISSUER\_SERIAL\_get0\_serial, OSSL\_ISSUER\_SERIAL\_set1\_issuer, OSSL\_ISSUER\_SERIAL\_set1\_issuerUID, OSSL\_ISSUER\_SERIAL\_set1\_serial, OSSL\_OBJECT\_DIGEST\_INFO\_get0\_digest, OSSL\_OBJECT\_DIGEST\_INFO\_set1\_digest - get and set Attribute Certificate holder fields

## SYNOPSIS

```
 #include <openssl/x509_acert.h>
 const GENERAL_NAMES *X509_ACERT_get0_holder_entityName(const X509_ACERT *x);
 OSSL_ISSUER_SERIAL *X509_ACERT_get0_holder_baseCertId(const X509_ACERT *x);
 OSSL_OBJECT_DIGEST_INFO * X509_ACERT_get0_holder_digest(const X509_ACERT *x);
 void X509_ACERT_set0_holder_entityName(X509_ACERT *x, GENERAL_NAMES *name);
 void X509_ACERT_set0_holder_baseCertId(X509_ACERT *x, OSSL_ISSUER_SERIAL *isss);
 void X509_ACERT_set0_holder_digest(X509_ACERT *x,
                                    OSSL_OBJECT_DIGEST_INFO *dinfo);
 X509_NAME *OSSL_ISSUER_SERIAL_get0_issuer(OSSL_ISSUER_SERIAL *isss);
 ASN1_INTEGER *OSSL_ISSUER_SERIAL_get0_serial(OSSL_ISSUER_SERIAL *isss);
 ASN1_BIT_STRING *OSSL_ISSUER_SERIAL_get0_issuerUID(OSSL_ISSUER_SERIAL *isss);
 int OSSL_ISSUER_SERIAL_set1_issuer(OSSL_ISSUER_SERIAL *isss, X509_NAME *issuer);
 int OSSL_ISSUER_SERIAL_set1_serial(OSSL_ISSUER_SERIAL *isss, ASN1_INTEGER *serial);
 int OSSL_ISSUER_SERIAL_set1_issuerUID(OSSL_ISSUER_SERIAL *isss, ASN1_BIT_STRING *uid);
 void OSSL_OBJECT_DIGEST_INFO_get0_digest(OSSL_OBJECT_DIGEST_INFO *o,
                                          ASN1_ENUMERATED **digestedObjectType,
                                          X509_ALGOR **digestAlgorithm,
                                          ASN1_BIT_STRING **digest);
 void OSSL_OBJECT_DIGEST_INFO_set1_digest(OSSL_OBJECT_DIGEST_INFO *o,
                                          ASN1_ENUMERATED *digestedObjectType,
                                          X509_ALGOR *digestAlgorithm,
                                          ASN1_BIT_STRING *digest);
```

## DESCRIPTION

These routines set and get the holder identity of an X509 attribute certificate.

**X509\_ACERT\_set0\_holder\_entityName()** sets the identity as a **GENERAL\_NAME** *name*, **X509\_ACERT\_set0\_holder\_baseCertId()** sets the identity based on the issuer and serial number of a certificate detailed in *isss* and **X509\_ACERT\_set0\_holder\_digest()** sets the holder entity based on digest information *dinfo*. Although RFC 5755 section 4.2.2 recommends that only one of the above methods be used to set the holder identity for a given attribute certificate *x*, setting multiple methods at the same time is possible.  It is up to the application to handle cases when conflicting identity information is specified using different methods.

Pointers to the internal structures describing the holder identity of attribute certificate *x* can be retrieved with **X509\_ACERT\_get0\_holder\_entityName()**, **X509\_ACERT\_get0\_holder\_baseCertId()**, and **X509\_ACERT\_get0\_holder\_digest()**.

A **OSSL\_ISSUER\_SERIAL** object holds the subject name and UID of a certificate issuer and a certificate's serial number.  **OSSL\_ISSUER\_SERIAL\_set1\_issuer()**, **OSSL\_ISSUER\_SERIAL\_set1\_issuerUID()**, and **OSSL\_ISSUER\_SERIAL\_set1\_serial()** respectively copy these values into the **OSSL\_ISSUER\_SERIAL** structure. The application is responsible for freeing its own copy of these values after use.  **OSSL\_ISSUER\_SERIAL\_get0\_issuer()**, **OSSL\_ISSUER\_SERIAL\_get0\_issuerUID()**, and **OSSL\_ISSUER\_SERIAL\_get0\_serial()** return pointers to these values in the object.

An **OSSL\_OBJECT\_DIGEST\_INFO** object holds a digest of data to identify the attribute certificate holder.  **OSSL\_OBJECT\_DIGEST\_INFO\_set1\_digest()** sets the digest information of the object.  The type of *digest* information is given by *digestedObjectType* and can be one of:

- OSSL\_OBJECT\_DIGEST\_INFO\_PUBLIC\_KEY

  Hash of a public key

- OSSL\_OBJECT\_DIGEST\_INFO\_PUBLIC\_KEY\_CERT

  Hash of a public key certificate

- OSSL\_OBJECT\_DIGEST\_INFO\_OTHER

  Hash of another object. See NOTES below.

*digestAlgorithm* indicates the algorithm used to compute *digest*.

## RETURN VALUES

All *set0*/*set1* routines return 1 for success and 0 for failure. All *get0* functions return a pointer to the object's inner structure. These pointers must not be freed after use.

## NOTES

Although the value of **OSSL\_OBJECT\_DIGEST\_INFO\_OTHER** is defined in RFC 5755, its use is prohibited for conformant attribute certificates.

## HISTORY

These functions were added in OpenSSL 3.4.

## COPYRIGHT

Copyright 2023-2024 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\>.