1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for inet_sock
8 *
9 * Authors: Many, reorganised here by
10 * Arnaldo Carvalho de Melo <acme@mandriva.com>
11 */
12 #ifndef _INET_SOCK_H
13 #define _INET_SOCK_H
14
15 #include <linux/bitops.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/jhash.h>
19 #include <linux/netdevice.h>
20
21 #include <net/flow.h>
22 #include <net/sock.h>
23 #include <net/request_sock.h>
24 #include <net/netns/hash.h>
25 #include <net/tcp_states.h>
26 #include <net/l3mdev.h>
27
28 /** struct ip_options - IP Options
29 *
30 * @faddr - Saved first hop address
31 * @nexthop - Saved nexthop address in LSRR and SSRR
32 * @is_strictroute - Strict source route
33 * @srr_is_hit - Packet destination addr was our one
34 * @is_changed - IP checksum more not valid
35 * @rr_needaddr - Need to record addr of outgoing dev
36 * @ts_needtime - Need to record timestamp
37 * @ts_needaddr - Need to record addr of outgoing dev
38 */
39 struct ip_options {
40 __be32 faddr;
41 __be32 nexthop;
42 unsigned char optlen;
43 unsigned char srr;
44 unsigned char rr;
45 unsigned char ts;
46 unsigned char is_strictroute:1,
47 srr_is_hit:1,
48 is_changed:1,
49 rr_needaddr:1,
50 ts_needtime:1,
51 ts_needaddr:1;
52 unsigned char router_alert;
53 unsigned char cipso;
54 unsigned char __pad2;
55 unsigned char __data[];
56 };
57
58 struct ip_options_rcu {
59 struct rcu_head rcu;
60 struct ip_options opt;
61 };
62
63 struct ip_options_data {
64 struct ip_options_rcu opt;
65 char data[40];
66 };
67
68 struct inet_request_sock {
69 struct request_sock req;
70 #define ir_loc_addr req.__req_common.skc_rcv_saddr
71 #define ir_rmt_addr req.__req_common.skc_daddr
72 #define ir_num req.__req_common.skc_num
73 #define ir_rmt_port req.__req_common.skc_dport
74 #define ir_v6_rmt_addr req.__req_common.skc_v6_daddr
75 #define ir_v6_loc_addr req.__req_common.skc_v6_rcv_saddr
76 #define ir_iif req.__req_common.skc_bound_dev_if
77 #define ir_cookie req.__req_common.skc_cookie
78 #define ireq_net req.__req_common.skc_net
79 #define ireq_state req.__req_common.skc_state
80 #define ireq_family req.__req_common.skc_family
81
82 u16 snd_wscale : 4,
83 rcv_wscale : 4,
84 tstamp_ok : 1,
85 sack_ok : 1,
86 wscale_ok : 1,
87 ecn_ok : 1,
88 acked : 1,
89 no_srccheck: 1,
90 smc_ok : 1;
91 u32 ir_mark;
92 union {
93 struct ip_options_rcu __rcu *ireq_opt;
94 #if IS_ENABLED(CONFIG_IPV6)
95 struct {
96 struct ipv6_txoptions *ipv6_opt;
97 struct sk_buff *pktopts;
98 };
99 #endif
100 };
101 };
102
103 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
104 {
105 return (struct inet_request_sock *)sk;
106 }
107
108 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
109 {
110 u32 mark = READ_ONCE(sk->sk_mark);
111
112 if (!mark && READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept))
113 return skb->mark;
114
115 return mark;
116 }
117
118 static inline int inet_request_bound_dev_if(const struct sock *sk,
119 struct sk_buff *skb)
120 {
121 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
122 #ifdef CONFIG_NET_L3_MASTER_DEV
123 struct net *net = sock_net(sk);
124
125 if (!bound_dev_if && READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept))
126 return l3mdev_master_ifindex_by_index(net, skb->skb_iif);
127 #endif
128
129 return bound_dev_if;
130 }
131
132 static inline int inet_sk_bound_l3mdev(const struct sock *sk)
133 {
134 #ifdef CONFIG_NET_L3_MASTER_DEV
135 struct net *net = sock_net(sk);
136
137 if (!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept))
138 return l3mdev_master_ifindex_by_index(net,
139 sk->sk_bound_dev_if);
140 #endif
141
142 return 0;
143 }
144
145 static inline bool inet_bound_dev_eq(bool l3mdev_accept, int bound_dev_if,
146 int dif, int sdif)
147 {
148 if (!bound_dev_if)
149 return !sdif || l3mdev_accept;
150 return bound_dev_if == dif || bound_dev_if == sdif;
151 }
152
153 static inline bool inet_sk_bound_dev_eq(struct net *net, int bound_dev_if,
154 int dif, int sdif)
155 {
156 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
157 return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept),
158 bound_dev_if, dif, sdif);
159 #else
160 return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
161 #endif
162 }
163
164 struct inet_cork {
165 unsigned int flags;
166 __be32 addr;
167 struct ip_options *opt;
168 unsigned int fragsize;
169 int length; /* Total length of all frames */
170 struct dst_entry *dst;
171 u8 tx_flags;
172 __u8 ttl;
173 __s16 tos;
174 char priority;
175 __u16 gso_size;
176 u64 transmit_time;
177 u32 mark;
178 };
179
180 struct inet_cork_full {
181 struct inet_cork base;
182 struct flowi fl;
183 };
184
185 struct ip_mc_socklist;
186 struct ipv6_pinfo;
187 struct rtable;
188
189 /** struct inet_sock - representation of INET sockets
190 *
191 * @sk - ancestor class
192 * @pinet6 - pointer to IPv6 control block
193 * @inet_daddr - Foreign IPv4 addr
194 * @inet_rcv_saddr - Bound local IPv4 addr
195 * @inet_dport - Destination port
196 * @inet_num - Local port
197 * @inet_flags - various atomic flags
198 * @inet_saddr - Sending source
199 * @uc_ttl - Unicast TTL
200 * @inet_sport - Source port
201 * @inet_id - ID counter for DF pkts
202 * @tos - TOS
203 * @mc_ttl - Multicasting TTL
204 * @uc_index - Unicast outgoing device index
205 * @mc_index - Multicast device index
206 * @mc_list - Group array
207 * @cork - info to build ip hdr on each ip frag while socket is corked
208 */
209 struct inet_sock {
210 /* sk and pinet6 has to be the first two members of inet_sock */
211 struct sock sk;
212 #if IS_ENABLED(CONFIG_IPV6)
213 struct ipv6_pinfo *pinet6;
214 #endif
215 /* Socket demultiplex comparisons on incoming packets. */
216 #define inet_daddr sk.__sk_common.skc_daddr
217 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr
218 #define inet_dport sk.__sk_common.skc_dport
219 #define inet_num sk.__sk_common.skc_num
220
221 unsigned long inet_flags;
222 __be32 inet_saddr;
223 __s16 uc_ttl;
224 __be16 inet_sport;
225 struct ip_options_rcu __rcu *inet_opt;
226 atomic_t inet_id;
227
228 __u8 tos;
229 __u8 min_ttl;
230 __u8 mc_ttl;
231 __u8 pmtudisc;
232 __u8 rcv_tos;
233 __u8 convert_csum;
234 int uc_index;
235 int mc_index;
236 __be32 mc_addr;
237 u32 local_port_range; /* high << 16 | low */
238
239 struct ip_mc_socklist __rcu *mc_list;
240 struct inet_cork_full cork;
241 };
242
243 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */
244
245 enum {
246 INET_FLAGS_PKTINFO = 0,
247 INET_FLAGS_TTL = 1,
248 INET_FLAGS_TOS = 2,
249 INET_FLAGS_RECVOPTS = 3,
250 INET_FLAGS_RETOPTS = 4,
251 INET_FLAGS_PASSSEC = 5,
252 INET_FLAGS_ORIGDSTADDR = 6,
253 INET_FLAGS_CHECKSUM = 7,
254 INET_FLAGS_RECVFRAGSIZE = 8,
255
256 INET_FLAGS_RECVERR = 9,
257 INET_FLAGS_RECVERR_RFC4884 = 10,
258 INET_FLAGS_FREEBIND = 11,
259 INET_FLAGS_HDRINCL = 12,
260 INET_FLAGS_MC_LOOP = 13,
261 INET_FLAGS_MC_ALL = 14,
262 INET_FLAGS_TRANSPARENT = 15,
263 INET_FLAGS_IS_ICSK = 16,
264 INET_FLAGS_NODEFRAG = 17,
265 INET_FLAGS_BIND_ADDRESS_NO_PORT = 18,
266 INET_FLAGS_DEFER_CONNECT = 19,
267 INET_FLAGS_MC6_LOOP = 20,
268 INET_FLAGS_RECVERR6_RFC4884 = 21,
269 INET_FLAGS_MC6_ALL = 22,
270 INET_FLAGS_AUTOFLOWLABEL_SET = 23,
271 INET_FLAGS_AUTOFLOWLABEL = 24,
272 INET_FLAGS_DONTFRAG = 25,
273 INET_FLAGS_RECVERR6 = 26,
274 INET_FLAGS_REPFLOW = 27,
275 INET_FLAGS_RTALERT_ISOLATE = 28,
276 INET_FLAGS_SNDFLOW = 29,
277 INET_FLAGS_RTALERT = 30,
278 };
279
280 /* cmsg flags for inet */
281 #define IP_CMSG_PKTINFO BIT(INET_FLAGS_PKTINFO)
282 #define IP_CMSG_TTL BIT(INET_FLAGS_TTL)
283 #define IP_CMSG_TOS BIT(INET_FLAGS_TOS)
284 #define IP_CMSG_RECVOPTS BIT(INET_FLAGS_RECVOPTS)
285 #define IP_CMSG_RETOPTS BIT(INET_FLAGS_RETOPTS)
286 #define IP_CMSG_PASSSEC BIT(INET_FLAGS_PASSSEC)
287 #define IP_CMSG_ORIGDSTADDR BIT(INET_FLAGS_ORIGDSTADDR)
288 #define IP_CMSG_CHECKSUM BIT(INET_FLAGS_CHECKSUM)
289 #define IP_CMSG_RECVFRAGSIZE BIT(INET_FLAGS_RECVFRAGSIZE)
290
291 #define IP_CMSG_ALL (IP_CMSG_PKTINFO | IP_CMSG_TTL | \
292 IP_CMSG_TOS | IP_CMSG_RECVOPTS | \
293 IP_CMSG_RETOPTS | IP_CMSG_PASSSEC | \
294 IP_CMSG_ORIGDSTADDR | IP_CMSG_CHECKSUM | \
295 IP_CMSG_RECVFRAGSIZE)
296
297 static inline unsigned long inet_cmsg_flags(const struct inet_sock *inet)
298 {
299 return READ_ONCE(inet->inet_flags) & IP_CMSG_ALL;
300 }
301
302 #define inet_test_bit(nr, sk) \
303 test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
304 #define inet_set_bit(nr, sk) \
305 set_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
306 #define inet_clear_bit(nr, sk) \
307 clear_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
308 #define inet_assign_bit(nr, sk, val) \
309 assign_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags, val)
310
311 /**
312 * sk_to_full_sk - Access to a full socket
313 * @sk: pointer to a socket
314 *
315 * SYNACK messages might be attached to request sockets.
316 * Some places want to reach the listener in this case.
317 */
318 static inline struct sock *sk_to_full_sk(struct sock *sk)
319 {
320 #ifdef CONFIG_INET
321 if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
322 sk = inet_reqsk(sk)->rsk_listener;
323 #endif
324 return sk;
325 }
326
327 /* sk_to_full_sk() variant with a const argument */
328 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk)
329 {
330 #ifdef CONFIG_INET
331 if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
332 sk = ((const struct request_sock *)sk)->rsk_listener;
333 #endif
334 return sk;
335 }
336
337 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
338 {
339 return sk_to_full_sk(skb->sk);
340 }
341
342 #define inet_sk(ptr) container_of_const(ptr, struct inet_sock, sk)
343
344 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
345 const struct sock *sk_from,
346 const int ancestor_size)
347 {
348 memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
349 sk_from->sk_prot->obj_size - ancestor_size);
350 }
351
352 int inet_sk_rebuild_header(struct sock *sk);
353
354 /**
355 * inet_sk_state_load - read sk->sk_state for lockless contexts
356 * @sk: socket pointer
357 *
358 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock:
359 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ...
360 */
361 static inline int inet_sk_state_load(const struct sock *sk)
362 {
363 /* state change might impact lockless readers. */
364 return smp_load_acquire(&sk->sk_state);
365 }
366
367 /**
368 * inet_sk_state_store - update sk->sk_state
369 * @sk: socket pointer
370 * @newstate: new state
371 *
372 * Paired with inet_sk_state_load(). Should be used in contexts where
373 * state change might impact lockless readers.
374 */
375 void inet_sk_state_store(struct sock *sk, int newstate);
376
377 void inet_sk_set_state(struct sock *sk, int state);
378
379 static inline unsigned int __inet_ehashfn(const __be32 laddr,
380 const __u16 lport,
381 const __be32 faddr,
382 const __be16 fport,
383 u32 initval)
384 {
385 return jhash_3words((__force __u32) laddr,
386 (__force __u32) faddr,
387 ((__u32) lport) << 16 | (__force __u32)fport,
388 initval);
389 }
390
391 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
392 struct sock *sk_listener,
393 bool attach_listener);
394
395 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
396 {
397 __u8 flags = 0;
398
399 if (inet_test_bit(TRANSPARENT, sk) || inet_test_bit(HDRINCL, sk))
400 flags |= FLOWI_FLAG_ANYSRC;
401 return flags;
402 }
403
404 static inline void inet_inc_convert_csum(struct sock *sk)
405 {
406 inet_sk(sk)->convert_csum++;
407 }
408
409 static inline void inet_dec_convert_csum(struct sock *sk)
410 {
411 if (inet_sk(sk)->convert_csum > 0)
412 inet_sk(sk)->convert_csum--;
413 }
414
415 static inline bool inet_get_convert_csum(struct sock *sk)
416 {
417 return !!inet_sk(sk)->convert_csum;
418 }
419
420
421 static inline bool inet_can_nonlocal_bind(struct net *net,
422 struct inet_sock *inet)
423 {
424 return READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind) ||
425 test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) ||
426 test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags);
427 }
428
429 static inline bool inet_addr_valid_or_nonlocal(struct net *net,
430 struct inet_sock *inet,
431 __be32 addr,
432 int addr_type)
433 {
434 return inet_can_nonlocal_bind(net, inet) ||
435 addr == htonl(INADDR_ANY) ||
436 addr_type == RTN_LOCAL ||
437 addr_type == RTN_MULTICAST ||
438 addr_type == RTN_BROADCAST;
439 }
440
441 #endif /* _INET_SOCK_H */
442
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