Use modern ciphers & prefer server order

Set ciphers to prefer ChaCha20, ephemeral elliptic curve Diffie-Hellman, and AES with GCM mode, in that order.  Also add the flag to the SSL context to prefer the server's cipher ordering.

diff --git a/src/ssli_openssl.c b/src/ssli_openssl.c
index 0f631d20276a2c1dc0cca6ae5a085c95cdc53e87..009119d6280dddda18d0b46d754e029e3970f8f7 100644 (file)
--- a/src/ssli_openssl.c
+++ b/src/ssli_openssl.c
@@ -49,7 +49,7 @@ static RSA *rsa;
 static SSL_CTX *context;
 static EVP_PKEY *pkey;
 
-static char const * ciphers = "EECDH+AESGCM:AES256-SHA:AES128-SHA";
+static char const * ciphers = "EECDH+CHACHA20:EECDH+AESGCM:EECDH+AES+TLSv1.2:EECDH+AES:AESGCM:AES:!aNULL:!DHE:!kECDH";
 
 static int verify_callback(int preverify_ok, X509_STORE_CTX *ctx);
 
@@ -225,6 +225,7 @@ void SSLi_init(void)
        context = SSL_CTX_new(SSLv23_server_method());
        SSL_CTX_set_options(context, SSL_OP_NO_SSLv2);
        SSL_CTX_set_options(context, SSL_OP_NO_SSLv3);
+       SSL_CTX_set_options(context, SSL_OP_CIPHER_SERVER_PREFERENCE);
        if (context == NULL)
        {
                ERR_print_errors_fp(stderr);