linux_dsm_epyc7002/include/net/flow_dissector.h
Guillaume Nault 58cff782cc flow_dissector: Parse multiple MPLS Label Stack Entries
The current MPLS dissector only parses the first MPLS Label Stack
Entry (second LSE can be parsed too, but only to set a key_id).

This patch adds the possibility to parse several LSEs by making
__skb_flow_dissect_mpls() return FLOW_DISSECT_RET_PROTO_AGAIN as long
as the Bottom Of Stack bit hasn't been seen, up to a maximum of
FLOW_DIS_MPLS_MAX entries.

FLOW_DIS_MPLS_MAX is arbitrarily set to 7. This should be enough for
many practical purposes, without wasting too much space.

To record the parsed values, flow_dissector_key_mpls is modified to
store an array of stack entries, instead of just the values of the
first one. A bit field, "used_lses", is also added to keep track of
the LSEs that have been set. The objective is to avoid defining a
new FLOW_DISSECTOR_KEY_MPLS_XX for each level of the MPLS stack.

TC flower is adapted for the new struct flow_dissector_key_mpls layout.
Matching on several MPLS Label Stack Entries will be added in the next
patch.

The NFP and MLX5 drivers are also adapted: nfp_flower_compile_mac() and
mlx5's parse_tunnel() now verify that the rule only uses the first LSE
and fail if it doesn't.

Finally, the behaviour of the FLOW_DISSECTOR_KEY_MPLS_ENTROPY key is
slightly modified. Instead of recording the first Entropy Label, it
now records the last one. This shouldn't have any consequences since
there doesn't seem to have any user of FLOW_DISSECTOR_KEY_MPLS_ENTROPY
in the tree. We'd probably better do a hash of all parsed MPLS labels
instead (excluding reserved labels) anyway. That'd give better entropy
and would probably also simplify the code. But that's not the purpose
of this patch, so I'm keeping that as a future possible improvement.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-26 15:22:58 -07:00

373 lines
9.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NET_FLOW_DISSECTOR_H
#define _NET_FLOW_DISSECTOR_H
#include <linux/types.h>
#include <linux/in6.h>
#include <linux/siphash.h>
#include <linux/string.h>
#include <uapi/linux/if_ether.h>
struct sk_buff;
/**
* struct flow_dissector_key_control:
* @thoff: Transport header offset
*/
struct flow_dissector_key_control {
u16 thoff;
u16 addr_type;
u32 flags;
};
#define FLOW_DIS_IS_FRAGMENT BIT(0)
#define FLOW_DIS_FIRST_FRAG BIT(1)
#define FLOW_DIS_ENCAPSULATION BIT(2)
enum flow_dissect_ret {
FLOW_DISSECT_RET_OUT_GOOD,
FLOW_DISSECT_RET_OUT_BAD,
FLOW_DISSECT_RET_PROTO_AGAIN,
FLOW_DISSECT_RET_IPPROTO_AGAIN,
FLOW_DISSECT_RET_CONTINUE,
};
/**
* struct flow_dissector_key_basic:
* @n_proto: Network header protocol (eg. IPv4/IPv6)
* @ip_proto: Transport header protocol (eg. TCP/UDP)
*/
struct flow_dissector_key_basic {
__be16 n_proto;
u8 ip_proto;
u8 padding;
};
struct flow_dissector_key_tags {
u32 flow_label;
};
struct flow_dissector_key_vlan {
union {
struct {
u16 vlan_id:12,
vlan_dei:1,
vlan_priority:3;
};
__be16 vlan_tci;
};
__be16 vlan_tpid;
};
struct flow_dissector_mpls_lse {
u32 mpls_ttl:8,
mpls_bos:1,
mpls_tc:3,
mpls_label:20;
};
#define FLOW_DIS_MPLS_MAX 7
struct flow_dissector_key_mpls {
struct flow_dissector_mpls_lse ls[FLOW_DIS_MPLS_MAX]; /* Label Stack */
u8 used_lses; /* One bit set for each Label Stack Entry in use */
};
static inline void dissector_set_mpls_lse(struct flow_dissector_key_mpls *mpls,
int lse_index)
{
mpls->used_lses |= 1 << lse_index;
}
#define FLOW_DIS_TUN_OPTS_MAX 255
/**
* struct flow_dissector_key_enc_opts:
* @data: tunnel option data
* @len: length of tunnel option data
* @dst_opt_type: tunnel option type
*/
struct flow_dissector_key_enc_opts {
u8 data[FLOW_DIS_TUN_OPTS_MAX]; /* Using IP_TUNNEL_OPTS_MAX is desired
* here but seems difficult to #include
*/
u8 len;
__be16 dst_opt_type;
};
struct flow_dissector_key_keyid {
__be32 keyid;
};
/**
* struct flow_dissector_key_ipv4_addrs:
* @src: source ip address
* @dst: destination ip address
*/
struct flow_dissector_key_ipv4_addrs {
/* (src,dst) must be grouped, in the same way than in IP header */
__be32 src;
__be32 dst;
};
/**
* struct flow_dissector_key_ipv6_addrs:
* @src: source ip address
* @dst: destination ip address
*/
struct flow_dissector_key_ipv6_addrs {
/* (src,dst) must be grouped, in the same way than in IP header */
struct in6_addr src;
struct in6_addr dst;
};
/**
* struct flow_dissector_key_tipc:
* @key: source node address combined with selector
*/
struct flow_dissector_key_tipc {
__be32 key;
};
/**
* struct flow_dissector_key_addrs:
* @v4addrs: IPv4 addresses
* @v6addrs: IPv6 addresses
*/
struct flow_dissector_key_addrs {
union {
struct flow_dissector_key_ipv4_addrs v4addrs;
struct flow_dissector_key_ipv6_addrs v6addrs;
struct flow_dissector_key_tipc tipckey;
};
};
/**
* flow_dissector_key_arp:
* @ports: Operation, source and target addresses for an ARP header
* for Ethernet hardware addresses and IPv4 protocol addresses
* sip: Sender IP address
* tip: Target IP address
* op: Operation
* sha: Sender hardware address
* tpa: Target hardware address
*/
struct flow_dissector_key_arp {
__u32 sip;
__u32 tip;
__u8 op;
unsigned char sha[ETH_ALEN];
unsigned char tha[ETH_ALEN];
};
/**
* flow_dissector_key_tp_ports:
* @ports: port numbers of Transport header
* src: source port number
* dst: destination port number
*/
struct flow_dissector_key_ports {
union {
__be32 ports;
struct {
__be16 src;
__be16 dst;
};
};
};
/**
* flow_dissector_key_icmp:
* type: ICMP type
* code: ICMP code
* id: session identifier
*/
struct flow_dissector_key_icmp {
struct {
u8 type;
u8 code;
};
u16 id;
};
/**
* struct flow_dissector_key_eth_addrs:
* @src: source Ethernet address
* @dst: destination Ethernet address
*/
struct flow_dissector_key_eth_addrs {
/* (dst,src) must be grouped, in the same way than in ETH header */
unsigned char dst[ETH_ALEN];
unsigned char src[ETH_ALEN];
};
/**
* struct flow_dissector_key_tcp:
* @flags: flags
*/
struct flow_dissector_key_tcp {
__be16 flags;
};
/**
* struct flow_dissector_key_ip:
* @tos: tos
* @ttl: ttl
*/
struct flow_dissector_key_ip {
__u8 tos;
__u8 ttl;
};
/**
* struct flow_dissector_key_meta:
* @ingress_ifindex: ingress ifindex
* @ingress_iftype: ingress interface type
*/
struct flow_dissector_key_meta {
int ingress_ifindex;
u16 ingress_iftype;
};
/**
* struct flow_dissector_key_ct:
* @ct_state: conntrack state after converting with map
* @ct_mark: conttrack mark
* @ct_zone: conntrack zone
* @ct_labels: conntrack labels
*/
struct flow_dissector_key_ct {
u16 ct_state;
u16 ct_zone;
u32 ct_mark;
u32 ct_labels[4];
};
enum flow_dissector_key_id {
FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */
FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_vlan */
FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_tags */
FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_vlan */
FLOW_DISSECTOR_KEY_ENC_IP, /* struct flow_dissector_key_ip */
FLOW_DISSECTOR_KEY_ENC_OPTS, /* struct flow_dissector_key_enc_opts */
FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
FLOW_DISSECTOR_KEY_MAX,
};
#define FLOW_DISSECTOR_F_PARSE_1ST_FRAG BIT(0)
#define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL BIT(1)
#define FLOW_DISSECTOR_F_STOP_AT_ENCAP BIT(2)
struct flow_dissector_key {
enum flow_dissector_key_id key_id;
size_t offset; /* offset of struct flow_dissector_key_*
in target the struct */
};
struct flow_dissector {
unsigned int used_keys; /* each bit repesents presence of one key id */
unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
};
struct flow_keys_basic {
struct flow_dissector_key_control control;
struct flow_dissector_key_basic basic;
};
struct flow_keys {
struct flow_dissector_key_control control;
#define FLOW_KEYS_HASH_START_FIELD basic
struct flow_dissector_key_basic basic __aligned(SIPHASH_ALIGNMENT);
struct flow_dissector_key_tags tags;
struct flow_dissector_key_vlan vlan;
struct flow_dissector_key_vlan cvlan;
struct flow_dissector_key_keyid keyid;
struct flow_dissector_key_ports ports;
struct flow_dissector_key_icmp icmp;
/* 'addrs' must be the last member */
struct flow_dissector_key_addrs addrs;
};
#define FLOW_KEYS_HASH_OFFSET \
offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
__be32 flow_get_u32_src(const struct flow_keys *flow);
__be32 flow_get_u32_dst(const struct flow_keys *flow);
extern struct flow_dissector flow_keys_dissector;
extern struct flow_dissector flow_keys_basic_dissector;
/* struct flow_keys_digest:
*
* This structure is used to hold a digest of the full flow keys. This is a
* larger "hash" of a flow to allow definitively matching specific flows where
* the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
* that it can be used in CB of skb (see sch_choke for an example).
*/
#define FLOW_KEYS_DIGEST_LEN 16
struct flow_keys_digest {
u8 data[FLOW_KEYS_DIGEST_LEN];
};
void make_flow_keys_digest(struct flow_keys_digest *digest,
const struct flow_keys *flow);
static inline bool flow_keys_have_l4(const struct flow_keys *keys)
{
return (keys->ports.ports || keys->tags.flow_label);
}
u32 flow_hash_from_keys(struct flow_keys *keys);
void skb_flow_get_icmp_tci(const struct sk_buff *skb,
struct flow_dissector_key_icmp *key_icmp,
void *data, int thoff, int hlen);
static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
enum flow_dissector_key_id key_id)
{
return flow_dissector->used_keys & (1 << key_id);
}
static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
enum flow_dissector_key_id key_id,
void *target_container)
{
return ((char *)target_container) + flow_dissector->offset[key_id];
}
struct bpf_flow_dissector {
struct bpf_flow_keys *flow_keys;
const struct sk_buff *skb;
void *data;
void *data_end;
};
static inline void
flow_dissector_init_keys(struct flow_dissector_key_control *key_control,
struct flow_dissector_key_basic *key_basic)
{
memset(key_control, 0, sizeof(*key_control));
memset(key_basic, 0, sizeof(*key_basic));
}
#endif