[PATCH net-next v6 19/21] pfcp: always set pfcp metadata

From: Alexander Lobakin
Date: Wed Mar 27 2024 - 11:37:19 EST


From: Michal Swiatkowski <michal.swiatkowski@xxxxxxxxxxxxxxx>

In PFCP receive path set metadata needed by flower code to do correct
classification based on this metadata.

Signed-off-by: Michal Swiatkowski <michal.swiatkowski@xxxxxxxxxxxxxxx>
Signed-off-by: Marcin Szycik <marcin.szycik@xxxxxxxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx>
---
include/net/ip_tunnels.h | 3 +
include/net/pfcp.h | 73 ++++++++++++++++++++++
include/uapi/linux/if_tunnel.h | 3 +
include/uapi/linux/pkt_cls.h | 14 +++++
drivers/net/pfcp.c | 81 ++++++++++++++++++++++++-
net/core/net_test.c | 7 +--
net/sched/cls_flower.c | 107 +++++++++++++++++++++++++++++++++
7 files changed, 282 insertions(+), 6 deletions(-)

diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index ed8e48cc9054..d8f574fbb11e 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -216,6 +216,7 @@ static inline void ip_tunnel_set_options_present(unsigned long *flags)
__set_bit(IP_TUNNEL_VXLAN_OPT_BIT, present);
__set_bit(IP_TUNNEL_ERSPAN_OPT_BIT, present);
__set_bit(IP_TUNNEL_GTP_OPT_BIT, present);
+ __set_bit(IP_TUNNEL_PFCP_OPT_BIT, present);

ip_tunnel_flags_or(flags, flags, present);
}
@@ -228,6 +229,7 @@ static inline void ip_tunnel_clear_options_present(unsigned long *flags)
__set_bit(IP_TUNNEL_VXLAN_OPT_BIT, present);
__set_bit(IP_TUNNEL_ERSPAN_OPT_BIT, present);
__set_bit(IP_TUNNEL_GTP_OPT_BIT, present);
+ __set_bit(IP_TUNNEL_PFCP_OPT_BIT, present);

__ipt_flag_op(bitmap_andnot, flags, flags, present);
}
@@ -240,6 +242,7 @@ static inline bool ip_tunnel_is_options_present(const unsigned long *flags)
__set_bit(IP_TUNNEL_VXLAN_OPT_BIT, present);
__set_bit(IP_TUNNEL_ERSPAN_OPT_BIT, present);
__set_bit(IP_TUNNEL_GTP_OPT_BIT, present);
+ __set_bit(IP_TUNNEL_PFCP_OPT_BIT, present);

return ip_tunnel_flags_intersect(flags, present);
}
diff --git a/include/net/pfcp.h b/include/net/pfcp.h
index 3f9ebf27a8ff..af14f970b80e 100644
--- a/include/net/pfcp.h
+++ b/include/net/pfcp.h
@@ -2,12 +2,85 @@
#ifndef _PFCP_H_
#define _PFCP_H_

+#include <uapi/linux/if_ether.h>
+#include <net/dst_metadata.h>
#include <linux/netdevice.h>
+#include <uapi/linux/ipv6.h>
+#include <net/udp_tunnel.h>
+#include <uapi/linux/udp.h>
+#include <uapi/linux/ip.h>
#include <linux/string.h>
#include <linux/types.h>
+#include <linux/bits.h>

#define PFCP_PORT 8805

+/* PFCP protocol header */
+struct pfcphdr {
+ u8 flags;
+ u8 message_type;
+ __be16 message_length;
+};
+
+/* PFCP header flags */
+#define PFCP_SEID_FLAG BIT(0)
+#define PFCP_MP_FLAG BIT(1)
+
+#define PFCP_VERSION_MASK GENMASK(4, 0)
+
+#define PFCP_HLEN (sizeof(struct udphdr) + sizeof(struct pfcphdr))
+
+/* PFCP node related messages */
+struct pfcphdr_node {
+ u8 seq_number[3];
+ u8 reserved;
+};
+
+/* PFCP session related messages */
+struct pfcphdr_session {
+ __be64 seid;
+ u8 seq_number[3];
+#ifdef __LITTLE_ENDIAN_BITFIELD
+ u8 message_priority:4,
+ reserved:4;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+ u8 reserved:4,
+ message_priprity:4;
+#else
+#error "Please fix <asm/byteorder>"
+#endif
+};
+
+struct pfcp_metadata {
+ u8 type;
+ __be64 seid;
+} __packed;
+
+enum {
+ PFCP_TYPE_NODE = 0,
+ PFCP_TYPE_SESSION = 1,
+};
+
+#define PFCP_HEADROOM (sizeof(struct iphdr) + sizeof(struct udphdr) + \
+ sizeof(struct pfcphdr) + sizeof(struct ethhdr))
+#define PFCP6_HEADROOM (sizeof(struct ipv6hdr) + sizeof(struct udphdr) + \
+ sizeof(struct pfcphdr) + sizeof(struct ethhdr))
+
+static inline struct pfcphdr *pfcp_hdr(struct sk_buff *skb)
+{
+ return (struct pfcphdr *)(udp_hdr(skb) + 1);
+}
+
+static inline struct pfcphdr_node *pfcp_hdr_node(struct sk_buff *skb)
+{
+ return (struct pfcphdr_node *)(pfcp_hdr(skb) + 1);
+}
+
+static inline struct pfcphdr_session *pfcp_hdr_session(struct sk_buff *skb)
+{
+ return (struct pfcphdr_session *)(pfcp_hdr(skb) + 1);
+}
+
static inline bool netif_is_pfcp(const struct net_device *dev)
{
return dev->rtnl_link_ops &&
diff --git a/include/uapi/linux/if_tunnel.h b/include/uapi/linux/if_tunnel.h
index 838927dd73a4..e1a246dd8c62 100644
--- a/include/uapi/linux/if_tunnel.h
+++ b/include/uapi/linux/if_tunnel.h
@@ -212,6 +212,9 @@ enum {
IP_TUNNEL_VTI_BIT,
IP_TUNNEL_SIT_ISATAP_BIT = IP_TUNNEL_VTI_BIT,

+ /* Flags starting from here are not available via the old UAPI */
+ IP_TUNNEL_PFCP_OPT_BIT, /* OPTIONS_PRESENT */
+
__IP_TUNNEL_FLAG_NUM,
};

diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index ea277039f89d..229fc925ec3a 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -587,6 +587,10 @@ enum {
* TCA_FLOWER_KEY_ENC_OPT_GTP_
* attributes
*/
+ TCA_FLOWER_KEY_ENC_OPTS_PFCP, /* Nested
+ * TCA_FLOWER_KEY_ENC_IPT_PFCP
+ * attributes
+ */
__TCA_FLOWER_KEY_ENC_OPTS_MAX,
};

@@ -636,6 +640,16 @@ enum {
#define TCA_FLOWER_KEY_ENC_OPT_GTP_MAX \
(__TCA_FLOWER_KEY_ENC_OPT_GTP_MAX - 1)

+enum {
+ TCA_FLOWER_KEY_ENC_OPT_PFCP_UNSPEC,
+ TCA_FLOWER_KEY_ENC_OPT_PFCP_TYPE, /* u8 */
+ TCA_FLOWER_KEY_ENC_OPT_PFCP_SEID, /* be64 */
+ __TCA_FLOWER_KEY_ENC_OPT_PFCP_MAX,
+};
+
+#define TCA_FLOWER_KEY_ENC_OPT_PFCP_MAX \
+ (__TCA_FLOWER_KEY_ENC_OPT_PFCP_MAX - 1)
+
enum {
TCA_FLOWER_KEY_MPLS_OPTS_UNSPEC,
TCA_FLOWER_KEY_MPLS_OPTS_LSE,
diff --git a/drivers/net/pfcp.c b/drivers/net/pfcp.c
index 3f1ee0ae7111..cc5b28c5f99f 100644
--- a/drivers/net/pfcp.c
+++ b/drivers/net/pfcp.c
@@ -21,6 +21,8 @@ struct pfcp_dev {
struct socket *sock;
struct net_device *dev;
struct net *net;
+
+ struct gro_cells gro_cells;
};

static unsigned int pfcp_net_id __read_mostly;
@@ -29,6 +31,78 @@ struct pfcp_net {
struct list_head pfcp_dev_list;
};

+static void
+pfcp_session_recv(struct pfcp_dev *pfcp, struct sk_buff *skb,
+ struct pfcp_metadata *md)
+{
+ struct pfcphdr_session *unparsed = pfcp_hdr_session(skb);
+
+ md->seid = unparsed->seid;
+ md->type = PFCP_TYPE_SESSION;
+}
+
+static void
+pfcp_node_recv(struct pfcp_dev *pfcp, struct sk_buff *skb,
+ struct pfcp_metadata *md)
+{
+ md->type = PFCP_TYPE_NODE;
+}
+
+static int pfcp_encap_recv(struct sock *sk, struct sk_buff *skb)
+{
+ IP_TUNNEL_DECLARE_FLAGS(flags) = { };
+ struct metadata_dst *tun_dst;
+ struct pfcp_metadata *md;
+ struct pfcphdr *unparsed;
+ struct pfcp_dev *pfcp;
+
+ if (unlikely(!pskb_may_pull(skb, PFCP_HLEN)))
+ goto drop;
+
+ pfcp = rcu_dereference_sk_user_data(sk);
+ if (unlikely(!pfcp))
+ goto drop;
+
+ unparsed = pfcp_hdr(skb);
+
+ ip_tunnel_flags_zero(flags);
+ tun_dst = udp_tun_rx_dst(skb, sk->sk_family, flags, 0,
+ sizeof(*md));
+ if (unlikely(!tun_dst))
+ goto drop;
+
+ md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
+ if (unlikely(!md))
+ goto drop;
+
+ if (unparsed->flags & PFCP_SEID_FLAG)
+ pfcp_session_recv(pfcp, skb, md);
+ else
+ pfcp_node_recv(pfcp, skb, md);
+
+ __set_bit(IP_TUNNEL_PFCP_OPT_BIT, flags);
+ ip_tunnel_info_opts_set(&tun_dst->u.tun_info, md, sizeof(*md),
+ flags);
+
+ if (unlikely(iptunnel_pull_header(skb, PFCP_HLEN, skb->protocol,
+ !net_eq(sock_net(sk),
+ dev_net(pfcp->dev)))))
+ goto drop;
+
+ skb_dst_set(skb, (struct dst_entry *)tun_dst);
+
+ skb_reset_network_header(skb);
+ skb_reset_mac_header(skb);
+ skb->dev = pfcp->dev;
+
+ gro_cells_receive(&pfcp->gro_cells, skb);
+
+ return 0;
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+
static void pfcp_del_sock(struct pfcp_dev *pfcp)
{
udp_tunnel_sock_release(pfcp->sock);
@@ -39,6 +113,7 @@ static void pfcp_dev_uninit(struct net_device *dev)
{
struct pfcp_dev *pfcp = netdev_priv(dev);

+ gro_cells_destroy(&pfcp->gro_cells);
pfcp_del_sock(pfcp);
}

@@ -48,7 +123,7 @@ static int pfcp_dev_init(struct net_device *dev)

pfcp->dev = dev;

- return 0;
+ return gro_cells_init(&pfcp->gro_cells, dev);
}

static const struct net_device_ops pfcp_netdev_ops = {
@@ -94,6 +169,10 @@ static struct socket *pfcp_create_sock(struct pfcp_dev *pfcp)
if (err)
return ERR_PTR(err);

+ tuncfg.sk_user_data = pfcp;
+ tuncfg.encap_rcv = pfcp_encap_recv;
+ tuncfg.encap_type = 1;
+
setup_udp_tunnel_sock(net, sock, &tuncfg);

return sock;
diff --git a/net/core/net_test.c b/net/core/net_test.c
index 30062b9621e4..9c3a590865d2 100644
--- a/net/core/net_test.c
+++ b/net/core/net_test.c
@@ -335,11 +335,8 @@ static const struct ip_tunnel_flags_test ip_tunnel_flags_test[] = {
ip_tunnel_flags_1),
IP_TUNNEL_FLAGS_TEST("conflict", ip_tunnel_flags_2_src, true,
VTI_ISVTI, ip_tunnel_flags_2_exp),
- IP_TUNNEL_FLAGS_TEST("new", ip_tunnel_flags_3_src,
- /* This must be set to ``false`` once
- * ``__IP_TUNNEL_FLAG_NUM`` goes above 17.
- */
- true, cpu_to_be16(BIT(IP_TUNNEL_VXLAN_OPT_BIT)),
+ IP_TUNNEL_FLAGS_TEST("new", ip_tunnel_flags_3_src, false,
+ cpu_to_be16(BIT(IP_TUNNEL_VXLAN_OPT_BIT)),
ip_tunnel_flags_3_exp),
};

diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index ae14d649140f..fd9a6f20b60b 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -28,6 +28,7 @@
#include <net/vxlan.h>
#include <net/erspan.h>
#include <net/gtp.h>
+#include <net/pfcp.h>
#include <net/tc_wrapper.h>

#include <net/dst.h>
@@ -741,6 +742,7 @@ enc_opts_policy[TCA_FLOWER_KEY_ENC_OPTS_MAX + 1] = {
[TCA_FLOWER_KEY_ENC_OPTS_VXLAN] = { .type = NLA_NESTED },
[TCA_FLOWER_KEY_ENC_OPTS_ERSPAN] = { .type = NLA_NESTED },
[TCA_FLOWER_KEY_ENC_OPTS_GTP] = { .type = NLA_NESTED },
+ [TCA_FLOWER_KEY_ENC_OPTS_PFCP] = { .type = NLA_NESTED },
};

static const struct nla_policy
@@ -770,6 +772,12 @@ gtp_opt_policy[TCA_FLOWER_KEY_ENC_OPT_GTP_MAX + 1] = {
[TCA_FLOWER_KEY_ENC_OPT_GTP_QFI] = { .type = NLA_U8 },
};

+static const struct nla_policy
+pfcp_opt_policy[TCA_FLOWER_KEY_ENC_OPT_PFCP_MAX + 1] = {
+ [TCA_FLOWER_KEY_ENC_OPT_PFCP_TYPE] = { .type = NLA_U8 },
+ [TCA_FLOWER_KEY_ENC_OPT_PFCP_SEID] = { .type = NLA_U64 },
+};
+
static const struct nla_policy
mpls_stack_entry_policy[TCA_FLOWER_KEY_MPLS_OPT_LSE_MAX + 1] = {
[TCA_FLOWER_KEY_MPLS_OPT_LSE_DEPTH] = { .type = NLA_U8 },
@@ -1419,6 +1427,44 @@ static int fl_set_gtp_opt(const struct nlattr *nla, struct fl_flow_key *key,
return sizeof(*sinfo);
}

+static int fl_set_pfcp_opt(const struct nlattr *nla, struct fl_flow_key *key,
+ int depth, int option_len,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[TCA_FLOWER_KEY_ENC_OPT_PFCP_MAX + 1];
+ struct pfcp_metadata *md;
+ int err;
+
+ md = (struct pfcp_metadata *)&key->enc_opts.data[key->enc_opts.len];
+ memset(md, 0xff, sizeof(*md));
+
+ if (!depth)
+ return sizeof(*md);
+
+ if (nla_type(nla) != TCA_FLOWER_KEY_ENC_OPTS_PFCP) {
+ NL_SET_ERR_MSG_MOD(extack, "Non-pfcp option type for mask");
+ return -EINVAL;
+ }
+
+ err = nla_parse_nested(tb, TCA_FLOWER_KEY_ENC_OPT_PFCP_MAX, nla,
+ pfcp_opt_policy, extack);
+ if (err < 0)
+ return err;
+
+ if (!option_len && !tb[TCA_FLOWER_KEY_ENC_OPT_PFCP_TYPE]) {
+ NL_SET_ERR_MSG_MOD(extack, "Missing tunnel key pfcp option type");
+ return -EINVAL;
+ }
+
+ if (tb[TCA_FLOWER_KEY_ENC_OPT_PFCP_TYPE])
+ md->type = nla_get_u8(tb[TCA_FLOWER_KEY_ENC_OPT_PFCP_TYPE]);
+
+ if (tb[TCA_FLOWER_KEY_ENC_OPT_PFCP_SEID])
+ md->seid = nla_get_be64(tb[TCA_FLOWER_KEY_ENC_OPT_PFCP_SEID]);
+
+ return sizeof(*md);
+}
+
static int fl_set_enc_opt(struct nlattr **tb, struct fl_flow_key *key,
struct fl_flow_key *mask,
struct netlink_ext_ack *extack)
@@ -1576,6 +1622,36 @@ static int fl_set_enc_opt(struct nlattr **tb, struct fl_flow_key *key,
return -EINVAL;
}
break;
+ case TCA_FLOWER_KEY_ENC_OPTS_PFCP:
+ if (key->enc_opts.dst_opt_type) {
+ NL_SET_ERR_MSG_MOD(extack, "Duplicate type for pfcp options");
+ return -EINVAL;
+ }
+ option_len = 0;
+ key->enc_opts.dst_opt_type = IP_TUNNEL_PFCP_OPT_BIT;
+ option_len = fl_set_pfcp_opt(nla_opt_key, key,
+ key_depth, option_len,
+ extack);
+ if (option_len < 0)
+ return option_len;
+
+ key->enc_opts.len += option_len;
+ /* At the same time we need to parse through the mask
+ * in order to verify exact and mask attribute lengths.
+ */
+ mask->enc_opts.dst_opt_type = IP_TUNNEL_PFCP_OPT_BIT;
+ option_len = fl_set_pfcp_opt(nla_opt_msk, mask,
+ msk_depth, option_len,
+ extack);
+ if (option_len < 0)
+ return option_len;
+
+ mask->enc_opts.len += option_len;
+ if (key->enc_opts.len != mask->enc_opts.len) {
+ NL_SET_ERR_MSG_MOD(extack, "Key and mask miss aligned");
+ return -EINVAL;
+ }
+ break;
default:
NL_SET_ERR_MSG(extack, "Unknown tunnel option type");
return -EINVAL;
@@ -3118,6 +3194,32 @@ static int fl_dump_key_gtp_opt(struct sk_buff *skb,
return -EMSGSIZE;
}

+static int fl_dump_key_pfcp_opt(struct sk_buff *skb,
+ struct flow_dissector_key_enc_opts *enc_opts)
+{
+ struct pfcp_metadata *md;
+ struct nlattr *nest;
+
+ nest = nla_nest_start_noflag(skb, TCA_FLOWER_KEY_ENC_OPTS_PFCP);
+ if (!nest)
+ goto nla_put_failure;
+
+ md = (struct pfcp_metadata *)&enc_opts->data[0];
+ if (nla_put_u8(skb, TCA_FLOWER_KEY_ENC_OPT_PFCP_TYPE, md->type))
+ goto nla_put_failure;
+
+ if (nla_put_be64(skb, TCA_FLOWER_KEY_ENC_OPT_PFCP_SEID,
+ md->seid, 0))
+ goto nla_put_failure;
+
+ nla_nest_end(skb, nest);
+ return 0;
+
+nla_put_failure:
+ nla_nest_cancel(skb, nest);
+ return -EMSGSIZE;
+}
+
static int fl_dump_key_ct(struct sk_buff *skb,
struct flow_dissector_key_ct *key,
struct flow_dissector_key_ct *mask)
@@ -3223,6 +3325,11 @@ static int fl_dump_key_options(struct sk_buff *skb, int enc_opt_type,
if (err)
goto nla_put_failure;
break;
+ case IP_TUNNEL_PFCP_OPT_BIT:
+ err = fl_dump_key_pfcp_opt(skb, enc_opts);
+ if (err)
+ goto nla_put_failure;
+ break;
default:
goto nla_put_failure;
}
--
2.44.0