SSL_CIPHER_get_name, SSL_CIPHER_get_bits, SSL_CIPHER_get_version, SSL_CIPHER_description - get SSL_CIPHER properties
#include <openssl/ssl.h> const char *SSL_CIPHER_get_name(const SSL_CIPHER *cipher); int SSL_CIPHER_get_bits(const SSL_CIPHER *cipher, int *alg_bits); char *SSL_CIPHER_get_version(const SSL_CIPHER *cipher); char *SSL_CIPHER_description(const SSL_CIPHER *cipher, char *buf, int size); int SSL_CIPHER_get_cipher_nid(const SSL_CIPHER *c); int SSL_CIPHER_get_digest_nid(const SSL_CIPHER *c);
SSL_CIPHER_get_name() returns a pointer to the name of cipher. If the cipher is NULL, it returns "(NONE)".
SSL_CIPHER_get_bits() returns the number of secret bits used for cipher. If cipher is NULL, 0 is returned.
SSL_CIPHER_get_version() returns string which indicates the SSL/TLS protocol version that first defined the cipher. It returns "(NONE)" if cipher is NULL.
SSL_CIPHER_get_cipher_nid() returns the cipher NID corresponding to c. If there is no cipher (e.g. for ciphersuites with no encryption) then NID_undef is returned.
SSL_CIPHER_get_digest_nid() returns the digest NID corresponding to the MAC used by c. If there is no digest (e.g. for AEAD ciphersuites) then NID_undef is returned.
SSL_CIPHER_description() returns a textual description of the cipher used into the buffer buf of length len provided. If buf is provided, it must be at least 128 bytes, otherwise a buffer will be allocated using OPENSSL_malloc(). If the provided buffer is too small, or the allocation fails, NULL is returned.
The string returned by SSL_CIPHER_description() consists of several fields separated by whitespace:
Textual representation of the cipher name.
- <protocol version>
Protocol version, such as TLSv1.2, when the cipher was first defined.
- Kx=<key exchange>
Key exchange method such as RSA, ECDHE, etc.
Authentication method such as RSA, None, etc.. None is the representation of anonymous ciphers.
- Enc=<symmetric encryption method>
Encryption method, with number of secret bits, such as AESGCM(128).
- Mac=<message authentication code>
Message digest, such as SHA256.
Some examples for the output of SSL_CIPHER_description():
ECDHE-RSA-AES256-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(256) Mac=AEAD RSA-PSK-AES256-CBC-SHA384 TLSv1.0 Kx=RSAPSK Au=RSA Enc=AES(256) Mac=SHA384
SSL_CIPHER_get_version() was updated to always return the correct protocol string in OpenSSL 1.1.
SSL_CIPHER_description() was changed to return NULL on error, rather than a fixed string, in OpenSSL 1.1