Signed-off-by: Jonas Bonn <jo...@norrbonn.se>
---
drivers/net/gtp.c | 160 +++++++++++++++++++++++++----
include/uapi/linux/gtp.h | 12 +++
include/uapi/linux/if_tunnel.h | 1 +
tools/include/uapi/linux/if_link.h | 1 +
4 files changed, 156 insertions(+), 18 deletions(-)
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 8aab46ec8a94..668ed8a4836e 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -21,6 +21,7 @@
#include <linux/file.h>
#include <linux/gtp.h>
+#include <net/dst_metadata.h>
#include <net/net_namespace.h>
#include <net/protocol.h>
#include <net/ip.h>
@@ -74,6 +75,9 @@ struct gtp_dev {
unsigned int hash_size;
struct hlist_head *tid_hash;
struct hlist_head *addr_hash;
+ /* Used by LWT tunnel. */
+ bool collect_md;
+ struct socket *collect_md_sock;
};
static unsigned int gtp_net_id __read_mostly;
@@ -224,6 +228,51 @@ static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff
*skb,
return -1;
}
+static int gtp_set_tun_dst(struct pdp_ctx *pctx, struct sk_buff *skb,
+ unsigned int hdrlen)
+{
+ struct metadata_dst *tun_dst;
+ struct gtp1_header *gtp1;
+ int opts_len = 0;
+ __be64 tid;
+
+ gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
+
+ tid = key32_to_tunnel_id(gtp1->tid);
+
+ if (unlikely(gtp1->flags & GTP1_F_MASK))
+ opts_len = sizeof(struct gtpu_metadata);
+
+ tun_dst = udp_tun_rx_dst(skb,
+ pctx->sk->sk_family, TUNNEL_KEY, tid, opts_len);
+ if (!tun_dst) {
+ netdev_dbg(pctx->dev, "Failed to allocate tun_dst");
+ goto err;
+ }
+
+ netdev_dbg(pctx->dev, "attaching metadata_dst to skb, gtp ver %d hdrlen
%d\n",
+ pctx->gtp_version, hdrlen);
+ if (unlikely(opts_len)) {
+ struct gtpu_metadata *opts;
+
+ opts = ip_tunnel_info_opts(&tun_dst->u.tun_info);
+ opts->ver = GTP_METADATA_V1;
+ opts->flags = gtp1->flags;
+ opts->type = gtp1->type;
+ netdev_dbg(pctx->dev, "recved control pkt: flag %x type: %d\n",
+ opts->flags, opts->type);
+ tun_dst->u.tun_info.key.tun_flags |= TUNNEL_GTPU_OPT;
+ tun_dst->u.tun_info.options_len = opts_len;
+ skb->protocol = htons(0xffff); /* Unknown */
+ }
+
+ skb_dst_set(skb, &tun_dst->dst);
+ return 0;
+err:
+ return -1;
+}
+
+
/* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
{
@@ -262,6 +311,7 @@ static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct
sk_buff *skb)
unsigned int hdrlen = sizeof(struct udphdr) +
sizeof(struct gtp1_header);
struct gtp1_header *gtp1;
+ struct pdp_ctx md_pctx;
struct pdp_ctx *pctx;
if (!pskb_may_pull(skb, hdrlen))
@@ -272,6 +322,24 @@ static int gtp1u_udp_encap_recv(struct gtp_dev *gtp,
struct sk_buff *skb)
if ((gtp1->flags >> 5) != GTP_V1)
return 1;
+ if (ip_tunnel_collect_metadata() || gtp->collect_md) {
+ int err;
+
+ pctx = &md_pctx;
+
+ pctx->gtp_version = GTP_V1;
+ pctx->sk = gtp->sk1u;
+ pctx->dev = gtp->dev;
+
+ err = gtp_set_tun_dst(pctx, skb, hdrlen);
+ if (err) {
+ gtp->dev->stats.rx_dropped++;
+ return -1;
+ }
+
+ return gtp_rx(pctx, skb, hdrlen);
+ }
+
if (gtp1->type != GTP_TPDU)
return 1;
@@ -353,7 +421,8 @@ static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
if (!gtp)
return 1;
- netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
+ netdev_dbg(gtp->dev, "encap_recv sk=%p type %d\n",
+ sk, udp_sk(sk)->encap_type);
switch (udp_sk(sk)->encap_type) {
case UDP_ENCAP_GTP0:
@@ -539,7 +608,7 @@ static struct rtable *gtp_get_v4_rt(struct sk_buff *skb,
memset(&fl4, 0, sizeof(fl4));
fl4.flowi4_oif = sk->sk_bound_dev_if;
fl4.daddr = pctx->peer_addr_ip4.s_addr;
- fl4.saddr = inet_sk(sk)->inet_saddr;
+ fl4.saddr = *saddr;
fl4.flowi4_tos = RT_CONN_FLAGS(sk);
fl4.flowi4_proto = sk->sk_protocol;
@@ -617,29 +686,84 @@ static void gtp_push_header(struct sk_buff *skb, struct pdp_ctx *pctx,
static int gtp_xmit_ip4(struct sk_buff *skb, struct net_device *dev)
{
struct gtp_dev *gtp = netdev_priv(dev);
+ struct gtpu_metadata *opts = NULL;
+ struct pdp_ctx md_pctx;
struct pdp_ctx *pctx;
+ __be16 port;
struct rtable *rt;
- __be32 saddr;
struct iphdr *iph;
+ __be32 saddr;
int headroom;
- __be16 port;
+ __u8 tos;
int r;
- /* Read the IP destination address and resolve the PDP context.
- * Prepend PDP header with TEI/TID from PDP ctx.
- */
- iph = ip_hdr(skb);
- if (gtp->role == GTP_ROLE_SGSN)
- pctx = ipv4_pdp_find(gtp, iph->saddr);
- else
- pctx = ipv4_pdp_find(gtp, iph->daddr);
+ if (gtp->collect_md) {
+ /* LWT GTP1U encap */
+ struct ip_tunnel_info *info = NULL;
- if (!pctx) {
- netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
- &iph->daddr);
- return -ENOENT;
+ info = skb_tunnel_info(skb);
+ if (!info) {
+ netdev_dbg(dev, "missing tunnel info");
+ return -ENOENT;
+ }
+ if (info->key.tp_dst && ntohs(info->key.tp_dst) != GTP1U_PORT) {
+ netdev_dbg(dev, "unexpected GTP dst port: %d",
ntohs(info->key.tp_dst));
+ return -EOPNOTSUPP;
+ }
+
+ if (!gtp->sk1u) {
+ netdev_dbg(dev, "missing tunnel sock");
+ return -EOPNOTSUPP;
+ }
+
+ pctx = &md_pctx;
+ memset(pctx, 0, sizeof(*pctx));
+ pctx->sk = gtp->sk1u;
+ pctx->gtp_version = GTP_V1;
+ pctx->u.v1.o_tei = ntohl(tunnel_id_to_key32(info->key.tun_id));
+ pctx->peer_addr_ip4.s_addr = info->key.u.ipv4.dst;
+
+ saddr = info->key.u.ipv4.src;
+ tos = info->key.tos;
+
+ if (info->options_len != 0) {
+ if (info->key.tun_flags & TUNNEL_GTPU_OPT) {
+ opts = ip_tunnel_info_opts(info);
+ } else {
+ netdev_dbg(dev, "missing tunnel metadata for control
pkt");
+ return -EOPNOTSUPP;
+ }
+ }
+ netdev_dbg(dev, "flow-based GTP1U encap: tunnel id %d\n",
+ pctx->u.v1.o_tei);
+ } else {
+ struct iphdr *iph;
+
+ if (ntohs(skb->protocol) != ETH_P_IP)
+ return -EOPNOTSUPP;
+
+ iph = ip_hdr(skb);
+
+ /* Read the IP destination address and resolve the PDP context.
+ * Prepend PDP header with TEI/TID from PDP ctx.
+ */
+ if (gtp->role == GTP_ROLE_SGSN)
+ pctx = ipv4_pdp_find(gtp, iph->saddr);
+ else
+ pctx = ipv4_pdp_find(gtp, iph->daddr);
+
+ if (!pctx) {
+ netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
+ &iph->daddr);
+ return -ENOENT;
+ }
+ netdev_dbg(dev, "found PDP context %p\n", pctx);
+
+ saddr = inet_sk(pctx->sk)->inet_saddr;
+ tos = iph->tos;
+ netdev_dbg(dev, "gtp -> IP src: %pI4 dst: %pI4\n",
+ &iph->saddr, &iph->daddr);
}
- netdev_dbg(dev, "found PDP context %p\n", pctx);
rt = gtp_get_v4_rt(skb, dev, pctx, &saddr);
if (IS_ERR(rt)) {
@@ -691,7 +815,7 @@ static int gtp_xmit_ip4(struct sk_buff *skb, struct
net_device *dev)
udp_tunnel_xmit_skb(rt, pctx->sk, skb,
saddr, pctx->peer_addr_ip4.s_addr,
- iph->tos,
+ tos,
ip4_dst_hoplimit(&rt->dst),
0,
port, port,
diff --git a/include/uapi/linux/gtp.h b/include/uapi/linux/gtp.h
index 79f9191bbb24..62aff78b7c56 100644
--- a/include/uapi/linux/gtp.h
+++ b/include/uapi/linux/gtp.h
@@ -2,6 +2,8 @@
#ifndef _UAPI_LINUX_GTP_H_
#define _UAPI_LINUX_GTP_H_
+#include <linux/types.h>
+
#define GTP_GENL_MCGRP_NAME "gtp"
enum gtp_genl_cmds {
@@ -34,4 +36,14 @@ enum gtp_attrs {
};
#define GTPA_MAX (__GTPA_MAX + 1)
+enum {
+ GTP_METADATA_V1
+};
+
+struct gtpu_metadata {
+ __u8 ver;
+ __u8 flags;
+ __u8 type;
+};
+
#endif /* _UAPI_LINUX_GTP_H_ */
diff --git a/include/uapi/linux/if_tunnel.h b/include/uapi/linux/if_tunnel.h
index 7d9105533c7b..802da679fab1 100644
--- a/include/uapi/linux/if_tunnel.h
+++ b/include/uapi/linux/if_tunnel.h
@@ -176,6 +176,7 @@ enum {
#define TUNNEL_VXLAN_OPT __cpu_to_be16(0x1000)
#define TUNNEL_NOCACHE __cpu_to_be16(0x2000)
#define TUNNEL_ERSPAN_OPT __cpu_to_be16(0x4000)
+#define TUNNEL_GTPU_OPT __cpu_to_be16(0x8000)
#define TUNNEL_OPTIONS_PRESENT \
(TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT | TUNNEL_ERSPAN_OPT)
diff --git a/tools/include/uapi/linux/if_link.h
b/tools/include/uapi/linux/if_link.h
index d208b2af697f..28d649bda686 100644
--- a/tools/include/uapi/linux/if_link.h
+++ b/tools/include/uapi/linux/if_link.h
@@ -617,6 +617,7 @@ enum {
IFLA_GTP_FD1,
IFLA_GTP_PDP_HASHSIZE,
IFLA_GTP_ROLE,
+ IFLA_GTP_COLLECT_METADATA,
__IFLA_GTP_MAX,
};
#define IFLA_GTP_MAX (__IFLA_GTP_MAX - 1)
