setup

static VALUE
ossl_sslctx_setup(VALUE self)
{
    SSL_CTX *ctx;
    X509 *cert = NULL, *client_ca = NULL;
    EVP_PKEY *key = NULL;
    char *ca_path = NULL, *ca_file = NULL;
    int verify_mode;
    long i;
    VALUE val;

    if(OBJ_FROZEN(self)) return Qnil;
    GetSSLCTX(self, ctx);

#if !defined(OPENSSL_NO_DH)
    SSL_CTX_set_tmp_dh_callback(ctx, ossl_tmp_dh_callback);
#endif

#if !defined(OPENSSL_NO_EC)
    /* We added SSLContext#tmp_ecdh_callback= in Ruby 2.3.0,
     * but SSL_CTX_set_tmp_ecdh_callback() was removed in OpenSSL 1.1.0. */
    if (RTEST(rb_attr_get(self, id_i_tmp_ecdh_callback))) {
# if defined(HAVE_SSL_CTX_SET_TMP_ECDH_CALLBACK)
        rb_warn("#tmp_ecdh_callback= is deprecated; use #ecdh_curves= instead");
        SSL_CTX_set_tmp_ecdh_callback(ctx, ossl_tmp_ecdh_callback);
#  if defined(HAVE_SSL_CTX_SET_ECDH_AUTO)
        /* tmp_ecdh_callback and ecdh_auto conflict; OpenSSL ignores
         * tmp_ecdh_callback. So disable ecdh_auto. */
        if (!SSL_CTX_set_ecdh_auto(ctx, 0))
            ossl_raise(eSSLError, "SSL_CTX_set_ecdh_auto");
#  endif
# else
        ossl_raise(eSSLError, "OpenSSL does not support tmp_ecdh_callback; "
                   "use #ecdh_curves= instead");
# endif
    }
#endif /* OPENSSL_NO_EC */

    val = rb_attr_get(self, id_i_cert_store);
    if (!NIL_P(val)) {
        X509_STORE *store = GetX509StorePtr(val); /* NO NEED TO DUP */
        SSL_CTX_set_cert_store(ctx, store);
#if !defined(HAVE_X509_STORE_UP_REF)
        /*
         * WORKAROUND:
         *   X509_STORE can count references, but
         *   X509_STORE_free() doesn't care it.
         *   So we won't increment it but mark it by ex_data.
         */
        SSL_CTX_set_ex_data(ctx, ossl_sslctx_ex_store_p, ctx);
#else /* Fixed in OpenSSL 1.0.2; bff9ce4db38b (master), 5b4b9ce976fc (1.0.2) */
        X509_STORE_up_ref(store);
#endif
    }

    val = rb_attr_get(self, id_i_extra_chain_cert);
    if(!NIL_P(val)){
        rb_block_call(val, rb_intern("each"), 0, 0, ossl_sslctx_add_extra_chain_cert_i, self);
    }

    /* private key may be bundled in certificate file. */
    val = rb_attr_get(self, id_i_cert);
    cert = NIL_P(val) ? NULL : GetX509CertPtr(val); /* NO DUP NEEDED */
    val = rb_attr_get(self, id_i_key);
    key = NIL_P(val) ? NULL : GetPrivPKeyPtr(val); /* NO DUP NEEDED */
    if (cert && key) {
        if (!SSL_CTX_use_certificate(ctx, cert)) {
            /* Adds a ref => Safe to FREE */
            ossl_raise(eSSLError, "SSL_CTX_use_certificate");
        }
        if (!SSL_CTX_use_PrivateKey(ctx, key)) {
            /* Adds a ref => Safe to FREE */
            ossl_raise(eSSLError, "SSL_CTX_use_PrivateKey");
        }
        if (!SSL_CTX_check_private_key(ctx)) {
            ossl_raise(eSSLError, "SSL_CTX_check_private_key");
        }
    }

    val = rb_attr_get(self, id_i_client_ca);
    if(!NIL_P(val)){
        if (RB_TYPE_P(val, T_ARRAY)) {
            for(i = 0; i < RARRAY_LEN(val); i++){
                client_ca = GetX509CertPtr(RARRAY_AREF(val, i));
                if (!SSL_CTX_add_client_CA(ctx, client_ca)){
                    /* Copies X509_NAME => FREE it. */
                    ossl_raise(eSSLError, "SSL_CTX_add_client_CA");
                }
            }
        }
        else{
            client_ca = GetX509CertPtr(val); /* NO DUP NEEDED. */
            if (!SSL_CTX_add_client_CA(ctx, client_ca)){
                /* Copies X509_NAME => FREE it. */
                ossl_raise(eSSLError, "SSL_CTX_add_client_CA");
            }
        }
    }

    val = rb_attr_get(self, id_i_ca_file);
    ca_file = NIL_P(val) ? NULL : StringValueCStr(val);
    val = rb_attr_get(self, id_i_ca_path);
    ca_path = NIL_P(val) ? NULL : StringValueCStr(val);
    if(ca_file || ca_path){
        if (!SSL_CTX_load_verify_locations(ctx, ca_file, ca_path))
            rb_warning("can't set verify locations");
    }

    val = rb_attr_get(self, id_i_verify_mode);
    verify_mode = NIL_P(val) ? SSL_VERIFY_NONE : NUM2INT(val);
    SSL_CTX_set_verify(ctx, verify_mode, ossl_ssl_verify_callback);
    if (RTEST(rb_attr_get(self, id_i_client_cert_cb)))
        SSL_CTX_set_client_cert_cb(ctx, ossl_client_cert_cb);

    val = rb_attr_get(self, id_i_timeout);
    if(!NIL_P(val)) SSL_CTX_set_timeout(ctx, NUM2LONG(val));

    val = rb_attr_get(self, id_i_verify_depth);
    if(!NIL_P(val)) SSL_CTX_set_verify_depth(ctx, NUM2INT(val));

#ifndef OPENSSL_NO_NEXTPROTONEG
    val = rb_attr_get(self, id_i_npn_protocols);
    if (!NIL_P(val)) {
        VALUE encoded = ssl_encode_npn_protocols(val);
        rb_ivar_set(self, id_npn_protocols_encoded, encoded);
        SSL_CTX_set_next_protos_advertised_cb(ctx, ssl_npn_advertise_cb, (void *)encoded);
        OSSL_Debug("SSL NPN advertise callback added");
    }
    if (RTEST(rb_attr_get(self, id_i_npn_select_cb))) {
        SSL_CTX_set_next_proto_select_cb(ctx, ssl_npn_select_cb, (void *) self);
        OSSL_Debug("SSL NPN select callback added");
    }
#endif

#ifdef HAVE_SSL_CTX_SET_ALPN_SELECT_CB
    val = rb_attr_get(self, id_i_alpn_protocols);
    if (!NIL_P(val)) {
        VALUE rprotos = ssl_encode_npn_protocols(val);

        /* returns 0 on success */
        if (SSL_CTX_set_alpn_protos(ctx, (unsigned char *)RSTRING_PTR(rprotos),
                                    RSTRING_LENINT(rprotos)))
            ossl_raise(eSSLError, "SSL_CTX_set_alpn_protos");
        OSSL_Debug("SSL ALPN values added");
    }
    if (RTEST(rb_attr_get(self, id_i_alpn_select_cb))) {
        SSL_CTX_set_alpn_select_cb(ctx, ssl_alpn_select_cb, (void *) self);
        OSSL_Debug("SSL ALPN select callback added");
    }
#endif

    rb_obj_freeze(self);

    val = rb_attr_get(self, id_i_session_id_context);
    if (!NIL_P(val)){
        StringValue(val);
        if (!SSL_CTX_set_session_id_context(ctx, (unsigned char *)RSTRING_PTR(val),
                                            RSTRING_LENINT(val))){
            ossl_raise(eSSLError, "SSL_CTX_set_session_id_context");
        }
    }

    if (RTEST(rb_attr_get(self, id_i_session_get_cb))) {
        SSL_CTX_sess_set_get_cb(ctx, ossl_sslctx_session_get_cb);
        OSSL_Debug("SSL SESSION get callback added");
    }
    if (RTEST(rb_attr_get(self, id_i_session_new_cb))) {
        SSL_CTX_sess_set_new_cb(ctx, ossl_sslctx_session_new_cb);
        OSSL_Debug("SSL SESSION new callback added");
    }
    if (RTEST(rb_attr_get(self, id_i_session_remove_cb))) {
        SSL_CTX_sess_set_remove_cb(ctx, ossl_sslctx_session_remove_cb);
        OSSL_Debug("SSL SESSION remove callback added");
    }

    val = rb_attr_get(self, id_i_servername_cb);
    if (!NIL_P(val)) {
        SSL_CTX_set_tlsext_servername_callback(ctx, ssl_servername_cb);
        OSSL_Debug("SSL TLSEXT servername callback added");
    }

    return Qtrue;
}