diff mbox series

[RFC,net-next,v4,1/6] gtp: Allow to create GTP device without FDs

Message ID 20220204165045.10518-1-marcin.szycik@linux.intel.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series ice: GTP support in switchdev | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit fail Errors and warnings before: 0 this patch: 4
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn fail Errors and warnings before: 0 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 115 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Marcin Szycik Feb. 4, 2022, 4:50 p.m. UTC 
From: Wojciech Drewek <wojciech.drewek@intel.com>

Currently, when the user wants to create GTP device, he has to
provide file handles to the sockets created in userspace (IFLA_GTP_FD0,
IFLA_GTP_FD1). This behaviour is not ideal, considering the option of
adding support for GTP device creation through ip link. Ip link
application is not a good place to create such sockets.

This patch allows to create GTP device without providing
IFLA_GTP_FD0 and IFLA_GTP_FD1 arguments. If the user does not
provide file handles to the sockets, then GTP module takes care
of creating UDP sockets by itself. Sockets are created with the
commonly known UDP ports used for GTP protocol (GTP0_PORT and
GTP1U_PORT). In this case we don't have to provide encap_destroy
because no extra deinitialization is needed, everything is covered
by udp_tunnel_sock_release.

Signed-off-by: Wojciech Drewek <wojciech.drewek@intel.com>
---
v4: use ntohs when creating UDP socket
---
 drivers/net/gtp.c | 74 ++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 67 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 24e5c54d06c1..6fa1cfe023ef 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -66,8 +66,10 @@  struct gtp_dev {
 
 	struct sock		*sk0;
 	struct sock		*sk1u;
+	u8			sk_created;
 
 	struct net_device	*dev;
+	struct net		*net;
 
 	unsigned int		role;
 	unsigned int		hash_size;
@@ -320,8 +322,16 @@  static void gtp_encap_disable_sock(struct sock *sk)
 
 static void gtp_encap_disable(struct gtp_dev *gtp)
 {
-	gtp_encap_disable_sock(gtp->sk0);
-	gtp_encap_disable_sock(gtp->sk1u);
+	if (gtp->sk_created) {
+		udp_tunnel_sock_release(gtp->sk0->sk_socket);
+		udp_tunnel_sock_release(gtp->sk1u->sk_socket);
+		gtp->sk_created = false;
+		gtp->sk0 = NULL;
+		gtp->sk1u = NULL;
+	} else {
+		gtp_encap_disable_sock(gtp->sk0);
+		gtp_encap_disable_sock(gtp->sk1u);
+	}
 }
 
 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
@@ -664,9 +674,6 @@  static int gtp_newlink(struct net *src_net, struct net_device *dev,
 	struct gtp_net *gn;
 	int hashsize, err;
 
-	if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
-		return -EINVAL;
-
 	gtp = netdev_priv(dev);
 
 	if (!data[IFLA_GTP_PDP_HASHSIZE]) {
@@ -677,6 +684,8 @@  static int gtp_newlink(struct net *src_net, struct net_device *dev,
 			hashsize = 1024;
 	}
 
+	gtp->net = src_net;
+
 	err = gtp_hashtable_new(gtp, hashsize);
 	if (err < 0)
 		return err;
@@ -844,6 +853,38 @@  static struct sock *gtp_encap_enable_socket(int fd, int type,
 	return sk;
 }
 
+static struct sock *gtp_encap_create_sock(int type, struct gtp_dev *gtp)
+{
+	struct udp_tunnel_sock_cfg tuncfg = {};
+	struct udp_port_cfg udp_conf = {
+		.local_ip.s_addr	= htonl(INADDR_ANY),
+		.family			= AF_INET,
+	};
+	struct net *net = gtp->net;
+	struct socket *sock;
+	int err;
+
+	if (type == UDP_ENCAP_GTP0)
+		udp_conf.local_udp_port = ntohs(GTP0_PORT);
+	else if (type == UDP_ENCAP_GTP1U)
+		udp_conf.local_udp_port = ntohs(GTP1U_PORT);
+	else
+		return ERR_PTR(-EINVAL);
+
+	err = udp_sock_create(net, &udp_conf, &sock);
+	if (err)
+		return ERR_PTR(err);
+
+	tuncfg.sk_user_data = gtp;
+	tuncfg.encap_type = type;
+	tuncfg.encap_rcv = gtp_encap_recv;
+	tuncfg.encap_destroy = NULL;
+
+	setup_udp_tunnel_sock(net, sock, &tuncfg);
+
+	return sock->sk;
+}
+
 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
 {
 	struct sock *sk1u = NULL;
@@ -868,11 +909,30 @@  static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
 		}
 	}
 
+	if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1]) {
+		sk0 = gtp_encap_create_sock(UDP_ENCAP_GTP0, gtp);
+		if (IS_ERR(sk0))
+			return PTR_ERR(sk0);
+
+		sk1u = gtp_encap_create_sock(UDP_ENCAP_GTP1U, gtp);
+		if (IS_ERR(sk1u)) {
+			udp_tunnel_sock_release(sk0->sk_socket);
+			return PTR_ERR(sk1u);
+		}
+		gtp->sk_created = true;
+	}
+
 	if (data[IFLA_GTP_ROLE]) {
 		role = nla_get_u32(data[IFLA_GTP_ROLE]);
 		if (role > GTP_ROLE_SGSN) {
-			gtp_encap_disable_sock(sk0);
-			gtp_encap_disable_sock(sk1u);
+			if (gtp->sk_created) {
+				udp_tunnel_sock_release(sk0->sk_socket);
+				udp_tunnel_sock_release(sk1u->sk_socket);
+				gtp->sk_created = false;
+			} else {
+				gtp_encap_disable_sock(sk0);
+				gtp_encap_disable_sock(sk1u);
+			}
 			return -EINVAL;
 		}
 	}