SSL_get_version

SSL_GET_VERSION(3)        BSD Library Functions Manual        SSL_GET_VERSION(3)

NAME
     SSL_get_version, SSL_version — get the protocol version of a connection

SYNOPSIS
     #include <openssl/ssl.h>

     const char *
     SSL_get_version(const SSL *ssl);

     int
     SSL_version(const SSL *ssl);

DESCRIPTION
     SSL_get_version() returns the name of the protocol used for the connection
     ssl.

     SSL_version() returns an integer constant representing that protocol.

     These functions only return reliable results after the initial handshake
     has been completed.

RETURN VALUES
     The following strings or integers can be returned:

     "TLSv1" or TLS1_VERSION
             The connection uses the TLSv1.0 protocol.

     "TLSv1.1" or TLS1_1_VERSION
             The connection uses the TLSv1.1 protocol.

     "TLSv1.2" or TLS1_2_VERSION
             The connection uses the TLSv1.2 protocol.

     "TLSv1.3" or TLS1_3_VERSION
             The connection uses the TLSv1.3 protocol.

     "DTLSv1" or DTLS1_VERSION
             The connection uses the Datagram Transport Layer Security 1.0
             protocol.

     "unknown"
             This indicates an unknown protocol version; it cannot currently
             happen with LibreSSL.

SEE ALSO
     ssl(3)

HISTORY
     SSL_get_version() and SSL_version() first appeared in SSLeay 0.8.0 and have
     been available since OpenBSD 2.4.

BSD                              March 18, 2019                              BSD