tls: Add function to update the TLS socket configuration

The tx configuration is now stored in ctx->tx_conf.
And sk->sk_prot is updated trough a function
This will simplify things when we add rx
and support for different possible
tx and rx cross configurations.
Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/tls.h

@@ -83,6 +83,8 @@ struct tls_context {
 
 	void *priv_ctx;
 
+	u8 tx_conf:2;
+
 	u16 prepend_size;
 	u16 tag_size;
 	u16 overhead_size;

net/tls/tls_main.c

@@ -45,8 +45,18 @@ MODULE_AUTHOR("Mellanox Technologies");
 MODULE_DESCRIPTION("Transport Layer Security Support");
 MODULE_LICENSE("Dual BSD/GPL");
 
-static struct proto tls_base_prot;
-static struct proto tls_sw_prot;
+enum {
+	TLS_BASE_TX,
+	TLS_SW_TX,
+	TLS_NUM_CONFIG,
+};
+
+static struct proto tls_prots[TLS_NUM_CONFIG];
+
+static inline void update_sk_prot(struct sock *sk, struct tls_context *ctx)
+{
+	sk->sk_prot = &tls_prots[ctx->tx_conf];
+}
 
 int wait_on_pending_writer(struct sock *sk, long *timeo)
 {
@@ -340,8 +350,8 @@ static int do_tls_setsockopt_tx(struct sock *sk, char __user *optval,
 {
 	struct tls_crypto_info *crypto_info, tmp_crypto_info;
 	struct tls_context *ctx = tls_get_ctx(sk);
-	struct proto *prot = NULL;
 	int rc = 0;
+	int tx_conf;
 
 	if (!optval || (optlen < sizeof(*crypto_info))) {
 		rc = -EINVAL;
@@ -396,11 +406,12 @@ static int do_tls_setsockopt_tx(struct sock *sk, char __user *optval,
 
 	/* currently SW is default, we will have ethtool in future */
 	rc = tls_set_sw_offload(sk, ctx);
-	prot = &tls_sw_prot;
+	tx_conf = TLS_SW_TX;
 	if (rc)
 		goto err_crypto_info;
 
-	sk->sk_prot = prot;
+	ctx->tx_conf = tx_conf;
+	update_sk_prot(sk, ctx);
 	goto out;
 
 err_crypto_info:
@@ -453,7 +464,9 @@ static int tls_init(struct sock *sk)
 	icsk->icsk_ulp_data = ctx;
 	ctx->setsockopt = sk->sk_prot->setsockopt;
 	ctx->getsockopt = sk->sk_prot->getsockopt;
-	sk->sk_prot = &tls_base_prot;
+
+	ctx->tx_conf = TLS_BASE_TX;
+	update_sk_prot(sk, ctx);
 out:
 	return rc;
 }
@@ -464,16 +477,21 @@ static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 	.init			= tls_init,
 };
 
+static void build_protos(struct proto *prot, struct proto *base)
+{
+	prot[TLS_BASE_TX] = *base;
+	prot[TLS_BASE_TX].setsockopt = tls_setsockopt;
+	prot[TLS_BASE_TX].getsockopt = tls_getsockopt;
+
+	prot[TLS_SW_TX] = prot[TLS_BASE_TX];
+	prot[TLS_SW_TX].close		= tls_sk_proto_close;
+	prot[TLS_SW_TX].sendmsg		= tls_sw_sendmsg;
+	prot[TLS_SW_TX].sendpage	= tls_sw_sendpage;
+}
+
 static int __init tls_register(void)
 {
-	tls_base_prot			= tcp_prot;
-	tls_base_prot.setsockopt	= tls_setsockopt;
-	tls_base_prot.getsockopt	= tls_getsockopt;
-
-	tls_sw_prot			= tls_base_prot;
-	tls_sw_prot.sendmsg		= tls_sw_sendmsg;
-	tls_sw_prot.sendpage            = tls_sw_sendpage;
-	tls_sw_prot.close               = tls_sk_proto_close;
+	build_protos(tls_prots, &tcp_prot);
 
 	tcp_register_ulp(&tcp_tls_ulp_ops);