[PATCH v2 net-next 3/3] tls: Use correct sk->sk_prot for IPV6

[Ilya Lesokhin <ilyal@mellanox.com>]

The tls ulp overrides sk->prot with a new tls specific proto structs.
The tls specific structs were previously based on the ipv4 specific
tcp_prot sturct.
As a result, attaching the tls ulp to an ipv6 tcp socket replaced
some ipv6 callback with the ipv4 equivalents.

This patch adds ipv6 tls proto structs and uses them when
attached to ipv6 sockets.

Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
---
 net/tls/Kconfig    |  1 +
 net/tls/tls_main.c | 50 ++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/net/tls/Kconfig b/net/tls/Kconfig
index eb58303..7e9cf8b 100644
--- a/net/tls/Kconfig
+++ b/net/tls/Kconfig
@@ -7,6 +7,7 @@ config TLS
 	select CRYPTO
 	select CRYPTO_AES
 	select CRYPTO_GCM
+	select IPV6
 	default n
 	---help---
 	Enable kernel support for TLS protocol. This allows symmetric
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index 60aff60..9caad11 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -40,13 +40,25 @@
 #include <linux/sched/signal.h>
 
 #include <net/tls.h>
+#include <net/transp_v6.h>
 
 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 {
+	TLSV4,
+	TLSV6,
+	TLS_NUM_PROTS,
+};
+
+enum {
+	TLS_BASE_TX,
+	TLS_SW_TX,
+	TLS_NUM_CONFIG,
+};
+
+static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG];
 
 int wait_on_pending_writer(struct sock *sk, long *timeo)
 {
@@ -342,6 +354,7 @@ static int do_tls_setsockopt_tx(struct sock *sk, char __user *optval,
 	struct tls_context *ctx = tls_get_ctx(sk);
 	struct proto *prot = NULL;
 	int rc = 0;
+	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
 
 	if (!optval || (optlen < sizeof(*crypto_info))) {
 		rc = -EINVAL;
@@ -396,7 +409,7 @@ 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;
+	prot = &tls_prots[ip_ver][TLS_SW_TX];
 	if (rc)
 		goto err_crypto_info;
 
@@ -443,6 +456,12 @@ static int tls_init(struct sock *sk)
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tls_context *ctx;
 	int rc = 0;
+	int ip_ver = TLSV4;
+
+	if (sk->sk_prot == &tcpv6_prot)
+		ip_ver = TLSV6;
+	else if (sk->sk_prot != &tcp_prot)
+		return -EINVAL;
 
 	/* allocate tls context */
 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
@@ -453,7 +472,8 @@ 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;
+
+	sk->sk_prot = &tls_prots[ip_ver][TLS_BASE_TX];
 out:
 	return rc;
 }
@@ -464,16 +484,22 @@ static int tls_init(struct sock *sk)
 	.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[TLSV4], &tcp_prot);
+	build_protos(tls_prots[TLSV6], &tcpv6_prot);
 
 	tcp_register_ulp(&tcp_tls_ulp_ops);
 
-- 
1.8.3.1