OpenSSL

Cryptography and SSL/TLS Toolkit

SSL_get_ciphers

NAME

SSL_get1_supported_ciphers, SSL_get_client_ciphers, SSL_get_ciphers, SSL_CTX_get_ciphers, SSL_get_cipher_list - get list of available SSL_CIPHERs

SYNOPSIS

 #include <openssl/ssl.h>

 STACK_OF(SSL_CIPHER) *SSL_get_ciphers(const SSL *ssl);
 STACK_OF(SSL_CIPHER) *SSL_CTX_get_ciphers(const SSL_CTX *ctx);
 STACK_OF(SSL_CIPHER) *SSL_get1_supported_ciphers(SSL *s);
 STACK_OF(SSL_CIPHER) *SSL_get_client_ciphers(const SSL *ssl);
 const char *SSL_get_cipher_list(const SSL *ssl, int priority);

DESCRIPTION

SSL_get_ciphers() returns the stack of available SSL_CIPHERs for ssl, sorted by preference. If ssl is NULL or no ciphers are available, NULL is returned.

SSL_CTX_get_ciphers() returns the stack of available SSL_CIPHERs for ctx.

SSL_get1_supported_ciphers() returns the stack of enabled SSL_CIPHERs for ssl, sorted by preference. The list depends on settings like the cipher list, the supported protocol versions, the security level, and the enabled signature algorithms. SRP and PSK ciphers are only enabled if the appropriate callbacks or settings have been applied. This is the list that will be sent by the client to the server. The list supported by the server might include more ciphers in case there is a hole in the list of supported protocols. The server will also not use ciphers from this list depending on the configured certificates and DH parameters. If ssl is NULL or no ciphers are available, NULL is returned.

SSL_get_client_ciphers() returns the stack of available SSL_CIPHERs matching the list received from the client on ssl. If ssl is NULL, no ciphers are available, or ssl is not operating in server mode, NULL is returned.

SSL_get_cipher_list() returns a pointer to the name of the SSL_CIPHER listed for ssl with priority. If ssl is NULL, no ciphers are available, or there are less ciphers than priority available, NULL is returned.

NOTES

The details of the ciphers obtained by SSL_get_ciphers(), SSL_CTX_get_ciphers() SSL_get1_supported_ciphers() and SSL_get_client_ciphers() can be obtained using the SSL_CIPHER_get_name family of functions.

Call SSL_get_cipher_list() with priority starting from 0 to obtain the sorted list of available ciphers, until NULL is returned.

Note: SSL_get_ciphers(), SSL_CTX_get_ciphers() and SSL_get_client_ciphers() return a pointer to an internal cipher stack, which will be freed later on when the SSL or SSL_SESSION object is freed. Therefore, the calling code MUST NOT free the return value itself.

The stack returned by SSL_get1_supported_ciphers() should be freed using sk_SSL_CIPHER_free().

RETURN VALUES

See DESCRIPTION

SEE ALSO

ssl, SSL_CTX_set_cipher_list, SSL_CIPHER_get_name

Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the OpenSSL license (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.