1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _NET_FLOW_DISSECTOR_H
  3#define _NET_FLOW_DISSECTOR_H
  4
  5#include <linux/types.h>
  6#include <linux/in6.h>
  7#include <uapi/linux/if_ether.h>
  8
  9/**
 10 * struct flow_dissector_key_control:
 11 * @thoff: Transport header offset
 12 */
 13struct flow_dissector_key_control {
 14	u16	thoff;
 15	u16	addr_type;
 16	u32	flags;
 17};
 18
 19#define FLOW_DIS_IS_FRAGMENT	BIT(0)
 20#define FLOW_DIS_FIRST_FRAG	BIT(1)
 21#define FLOW_DIS_ENCAPSULATION	BIT(2)
 22
 23enum flow_dissect_ret {
 24	FLOW_DISSECT_RET_OUT_GOOD,
 25	FLOW_DISSECT_RET_OUT_BAD,
 26	FLOW_DISSECT_RET_PROTO_AGAIN,
 27	FLOW_DISSECT_RET_IPPROTO_AGAIN,
 28	FLOW_DISSECT_RET_CONTINUE,
 29};
 30
 31/**
 32 * struct flow_dissector_key_basic:
 33 * @thoff: Transport header offset
 34 * @n_proto: Network header protocol (eg. IPv4/IPv6)
 35 * @ip_proto: Transport header protocol (eg. TCP/UDP)
 36 */
 37struct flow_dissector_key_basic {
 38	__be16	n_proto;
 39	u8	ip_proto;
 40	u8	padding;
 41};
 42
 43struct flow_dissector_key_tags {
 44	u32	flow_label;
 45};
 46
 47struct flow_dissector_key_vlan {
 48	u16	vlan_id:12,
 49		vlan_priority:3;
 50	u16	padding;
 51};
 52
 53struct flow_dissector_key_mpls {
 54	u32	mpls_ttl:8,
 55		mpls_bos:1,
 56		mpls_tc:3,
 57		mpls_label:20;
 58};
 59
 60struct flow_dissector_key_keyid {
 61	__be32	keyid;
 62};
 63
 64/**
 65 * struct flow_dissector_key_ipv4_addrs:
 66 * @src: source ip address
 67 * @dst: destination ip address
 68 */
 69struct flow_dissector_key_ipv4_addrs {
 70	/* (src,dst) must be grouped, in the same way than in IP header */
 71	__be32 src;
 72	__be32 dst;
 73};
 74
 75/**
 76 * struct flow_dissector_key_ipv6_addrs:
 77 * @src: source ip address
 78 * @dst: destination ip address
 79 */
 80struct flow_dissector_key_ipv6_addrs {
 81	/* (src,dst) must be grouped, in the same way than in IP header */
 82	struct in6_addr src;
 83	struct in6_addr dst;
 84};
 85
 86/**
 87 * struct flow_dissector_key_tipc:
 88 * @key: source node address combined with selector
 89 */
 90struct flow_dissector_key_tipc {
 91	__be32 key;
 92};
 93
 94/**
 95 * struct flow_dissector_key_addrs:
 96 * @v4addrs: IPv4 addresses
 97 * @v6addrs: IPv6 addresses
 98 */
 99struct flow_dissector_key_addrs {
100	union {
101		struct flow_dissector_key_ipv4_addrs v4addrs;
102		struct flow_dissector_key_ipv6_addrs v6addrs;
103		struct flow_dissector_key_tipc tipckey;
104	};
105};
106
107/**
108 * flow_dissector_key_arp:
109 *	@ports: Operation, source and target addresses for an ARP header
110 *              for Ethernet hardware addresses and IPv4 protocol addresses
111 *		sip: Sender IP address
112 *		tip: Target IP address
113 *		op:  Operation
114 *		sha: Sender hardware address
115 *		tpa: Target hardware address
116 */
117struct flow_dissector_key_arp {
118	__u32 sip;
119	__u32 tip;
120	__u8 op;
121	unsigned char sha[ETH_ALEN];
122	unsigned char tha[ETH_ALEN];
123};
124
125/**
126 * flow_dissector_key_tp_ports:
127 *	@ports: port numbers of Transport header
128 *		src: source port number
129 *		dst: destination port number
130 */
131struct flow_dissector_key_ports {
132	union {
133		__be32 ports;
134		struct {
135			__be16 src;
136			__be16 dst;
137		};
138	};
139};
140
141/**
142 * flow_dissector_key_icmp:
143 *	@ports: type and code of ICMP header
144 *		icmp: ICMP type (high) and code (low)
145 *		type: ICMP type
146 *		code: ICMP code
147 */
148struct flow_dissector_key_icmp {
149	union {
150		__be16 icmp;
151		struct {
152			u8 type;
153			u8 code;
154		};
155	};
156};
157
158/**
159 * struct flow_dissector_key_eth_addrs:
160 * @src: source Ethernet address
161 * @dst: destination Ethernet address
162 */
163struct flow_dissector_key_eth_addrs {
164	/* (dst,src) must be grouped, in the same way than in ETH header */
165	unsigned char dst[ETH_ALEN];
166	unsigned char src[ETH_ALEN];
167};
168
169/**
170 * struct flow_dissector_key_tcp:
171 * @flags: flags
172 */
173struct flow_dissector_key_tcp {
174	__be16 flags;
175};
176
177/**
178 * struct flow_dissector_key_ip:
179 * @tos: tos
180 * @ttl: ttl
181 */
182struct flow_dissector_key_ip {
183	__u8	tos;
184	__u8	ttl;
185};
186
187enum flow_dissector_key_id {
188	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
189	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
190	FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
191	FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
192	FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */
193	FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */
194	FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */
195	FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */
196	FLOW_DISSECTOR_KEY_ARP, /* struct flow_dissector_key_arp */
197	FLOW_DISSECTOR_KEY_VLAN, /* struct flow_dissector_key_flow_vlan */
198	FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */
199	FLOW_DISSECTOR_KEY_GRE_KEYID, /* struct flow_dissector_key_keyid */
200	FLOW_DISSECTOR_KEY_MPLS_ENTROPY, /* struct flow_dissector_key_keyid */
201	FLOW_DISSECTOR_KEY_ENC_KEYID, /* struct flow_dissector_key_keyid */
202	FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */
203	FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */
204	FLOW_DISSECTOR_KEY_ENC_CONTROL, /* struct flow_dissector_key_control */
205	FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */
206	FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
207	FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
208	FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
209
210	FLOW_DISSECTOR_KEY_MAX,
211};
212
213#define FLOW_DISSECTOR_F_PARSE_1ST_FRAG		BIT(0)
214#define FLOW_DISSECTOR_F_STOP_AT_L3		BIT(1)
215#define FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL	BIT(2)
216#define FLOW_DISSECTOR_F_STOP_AT_ENCAP		BIT(3)
217
218struct flow_dissector_key {
219	enum flow_dissector_key_id key_id;
220	size_t offset; /* offset of struct flow_dissector_key_*
221			  in target the struct */
222};
223
224struct flow_dissector {
225	unsigned int used_keys; /* each bit repesents presence of one key id */
226	unsigned short int offset[FLOW_DISSECTOR_KEY_MAX];
227};
228
229struct flow_keys {
230	struct flow_dissector_key_control control;
231#define FLOW_KEYS_HASH_START_FIELD basic
232	struct flow_dissector_key_basic basic;
233	struct flow_dissector_key_tags tags;
234	struct flow_dissector_key_vlan vlan;
235	struct flow_dissector_key_keyid keyid;
236	struct flow_dissector_key_ports ports;
237	struct flow_dissector_key_addrs addrs;
238};
239
240#define FLOW_KEYS_HASH_OFFSET		\
241	offsetof(struct flow_keys, FLOW_KEYS_HASH_START_FIELD)
242
243__be32 flow_get_u32_src(const struct flow_keys *flow);
244__be32 flow_get_u32_dst(const struct flow_keys *flow);
245
246extern struct flow_dissector flow_keys_dissector;
247extern struct flow_dissector flow_keys_buf_dissector;
248
249/* struct flow_keys_digest:
250 *
251 * This structure is used to hold a digest of the full flow keys. This is a
252 * larger "hash" of a flow to allow definitively matching specific flows where
253 * the 32 bit skb->hash is not large enough. The size is limited to 16 bytes so
254 * that it can be used in CB of skb (see sch_choke for an example).
255 */
256#define FLOW_KEYS_DIGEST_LEN	16
257struct flow_keys_digest {
258	u8	data[FLOW_KEYS_DIGEST_LEN];
259};
260
261void make_flow_keys_digest(struct flow_keys_digest *digest,
262			   const struct flow_keys *flow);
263
264static inline bool flow_keys_have_l4(const struct flow_keys *keys)
265{
266	return (keys->ports.ports || keys->tags.flow_label);
267}
268
269u32 flow_hash_from_keys(struct flow_keys *keys);
270
271static inline bool dissector_uses_key(const struct flow_dissector *flow_dissector,
272				      enum flow_dissector_key_id key_id)
273{
274	return flow_dissector->used_keys & (1 << key_id);
275}
276
277static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
278					      enum flow_dissector_key_id key_id,
279					      void *target_container)
280{
281	return ((char *)target_container) + flow_dissector->offset[key_id];
282}
283
284#endif