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

# SSL\_CTX\_set\_cert\_store(3ssl)

manipulate X509 certificate verification storage

## NAME

SSL\_CTX\_set\_cert\_store, SSL\_CTX\_set1\_cert\_store, SSL\_CTX\_get\_cert\_store - manipulate X509 certificate verification storage

## SYNOPSIS

```
 #include <openssl/ssl.h>
 void SSL_CTX_set_cert_store(SSL_CTX *ctx, X509_STORE *store);
 void SSL_CTX_set1_cert_store(SSL_CTX *ctx, X509_STORE *store);
 X509_STORE *SSL_CTX_get_cert_store(const SSL_CTX *ctx);
```

## DESCRIPTION

**SSL\_CTX\_set\_cert\_store()** sets/replaces the certificate verification storage of **ctx** to/with **store**. If another X509\_STORE object is currently set in **ctx**, it will be **X509\_STORE\_free()**ed. **SSL\_CTX\_set\_cert\_store()** will take ownership of the **store**, i.e., the call `X509_STORE_free(store)` is no longer needed.

**SSL\_CTX\_set1\_cert\_store()** sets/replaces the certificate verification storage of **ctx** to/with **store**. The **store**'s reference count is incremented. If another X509\_STORE object is currently set in **ctx**, it will be **X509\_STORE\_free()**ed.

**SSL\_CTX\_get\_cert\_store()** returns a pointer to the current certificate verification storage. **ctx** **MUST NOT** be NULL.

## NOTES

In order to verify the certificates presented by the peer, trusted CA certificates must be accessed. These CA certificates are made available via lookup methods, handled inside the X509\_STORE. From the X509\_STORE the X509\_STORE\_CTX used when verifying certificates is created.

Typically the trusted certificate store is handled indirectly via using **SSL\_CTX\_load\_verify\_locations**(3). Using the **SSL\_CTX\_set\_cert\_store()** and **SSL\_CTX\_get\_cert\_store()** functions it is possible to manipulate the X509\_STORE object beyond the **SSL\_CTX\_load\_verify\_locations**(3) call.

Currently no detailed documentation on how to use the X509\_STORE object is available. Not all members of the X509\_STORE are used when the verification takes place. So will e.g. the **verify\_callback()** be overridden with the **verify\_callback()** set via the **SSL\_CTX\_set\_verify**(3) family of functions. This document must therefore be updated when documentation about the X509\_STORE object and its handling becomes available.

**SSL\_CTX\_set\_cert\_store()** does not increment the **store**'s reference count, so it should not be used to assign an X509\_STORE that is owned by another SSL\_CTX.

To share X509\_STOREs between two SSL\_CTXs, use **SSL\_CTX\_get\_cert\_store()** to get the X509\_STORE from the first SSL\_CTX, and then use **SSL\_CTX\_set1\_cert\_store()** to assign to the second SSL\_CTX and increment the reference count of the X509\_STORE.

## RESTRICTIONS

The X509\_STORE structure used by an SSL\_CTX is used for verifying peer certificates and building certificate chains, it is also shared by every child SSL structure. Applications wanting finer control can use functions such as **SSL\_CTX\_set1\_verify\_cert\_store()** instead.

## RETURN VALUES

**SSL\_CTX\_set\_cert\_store()** does not return diagnostic output.

**SSL\_CTX\_set1\_cert\_store()** does not return diagnostic output.

**SSL\_CTX\_get\_cert\_store()** returns the current setting.

## SEE ALSO

[**ssl**(7)](/ssl/7.md), **SSL\_CTX\_load\_verify\_locations**(3), **SSL\_CTX\_set\_verify**(3)

## COPYRIGHT

Copyright 2001-2024 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\>.