---
name: "SSL_CTX_config"
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_config"
---

# SSL\_CTX\_config(3ssl)

configure SSL\_CTX or SSL structure

## NAME

SSL\_CTX\_config, SSL\_config - configure SSL\_CTX or SSL structure

## SYNOPSIS

```
 #include <openssl/ssl.h>
 int SSL_CTX_config(SSL_CTX *ctx, const char *name);
 int SSL_config(SSL *s, const char *name);
```

## DESCRIPTION

The functions **SSL\_CTX\_config()** and **SSL\_config()** configure an **SSL\_CTX** or **SSL** structure using the configuration **name**.

By calling **SSL\_CTX\_config()** or **SSL\_config()** an application can perform many complex tasks based on the contents of the configuration file: greatly simplifying application configuration code. A degree of future proofing can also be achieved: an application can support configuration features in newer versions of OpenSSL automatically.

A configuration file must have been previously loaded, for example using **CONF\_modules\_load\_file()**. See [**config**(5)](/config/5.md) for details of the configuration file syntax.

## RETURN VALUES

**SSL\_CTX\_config()** and **SSL\_config()** return 1 for success or 0 if an error occurred.

## EXAMPLES

If the file "config.cnf" contains the following:

```
 testapp = test_sect
 [test_sect]
 # list of configuration modules
 ssl_conf = ssl_sect
 [ssl_sect]
 server = server_section
 [server_section]
 RSA.Certificate = server-rsa.pem
 ECDSA.Certificate = server-ecdsa.pem
 Ciphers = ALL:!RC4
```

An application could call:

```
 if (CONF_modules_load_file("config.cnf", "testapp", 0) <= 0) {
     fprintf(stderr, "Error processing config file\n");
     goto err;
 }
 ctx = SSL_CTX_new(TLS_server_method());
 if (SSL_CTX_config(ctx, "server") == 0) {
     fprintf(stderr, "Error configuring server.\n");
     goto err;
 }
```

In this example two certificates and the cipher list are configured without the need for any additional application code.

## SEE ALSO

[**ssl**(7)](/ssl/7.md), [**config**(5)](/config/5.md), **SSL\_CONF\_cmd**(3), **CONF\_modules\_load\_file**(3)

## HISTORY

The **SSL\_CTX\_config()** and **SSL\_config()** functions were added in OpenSSL 1.1.0.

## COPYRIGHT

Copyright 2015-2020 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\>.