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
inet_rsk(const struct request_sock * sk)103 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
104 {
105 return (struct inet_request_sock *)sk;
106 }
107
inet_request_mark(const struct sock * sk,struct sk_buff * skb)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
inet_request_bound_dev_if(const struct sock * sk,struct sk_buff * skb)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
inet_sk_bound_l3mdev(const struct sock * sk)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
inet_bound_dev_eq(bool l3mdev_accept,int bound_dev_if,int dif,int sdif)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
inet_sk_bound_dev_eq(const struct net * net,int bound_dev_if,int dif,int sdif)153 static inline bool inet_sk_bound_dev_eq(const struct net *net,
154 int bound_dev_if,
155 int dif, int sdif)
156 {
157 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
158 return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept),
159 bound_dev_if, dif, sdif);
160 #else
161 return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
162 #endif
163 }
164
165 struct inet_cork {
166 unsigned int flags;
167 __be32 addr;
168 struct ip_options *opt;
169 unsigned int fragsize;
170 int length; /* Total length of all frames */
171 struct dst_entry *dst;
172 u8 tx_flags;
173 __u8 ttl;
174 __s16 tos;
175 char priority;
176 __u16 gso_size;
177 u32 ts_opt_id;
178 u64 transmit_time;
179 u32 mark;
180 };
181
182 struct inet_cork_full {
183 struct inet_cork base;
184 struct flowi fl;
185 };
186
187 struct ip_mc_socklist;
188 struct ipv6_pinfo;
189 struct rtable;
190
191 /** struct inet_sock - representation of INET sockets
192 *
193 * @sk - ancestor class
194 * @pinet6 - pointer to IPv6 control block
195 * @inet_daddr - Foreign IPv4 addr
196 * @inet_rcv_saddr - Bound local IPv4 addr
197 * @inet_dport - Destination port
198 * @inet_num - Local port
199 * @inet_flags - various atomic flags
200 * @inet_saddr - Sending source
201 * @uc_ttl - Unicast TTL
202 * @inet_sport - Source port
203 * @inet_id - ID counter for DF pkts
204 * @tos - TOS
205 * @mc_ttl - Multicasting TTL
206 * @uc_index - Unicast outgoing device index
207 * @mc_index - Multicast device index
208 * @mc_list - Group array
209 * @cork - info to build ip hdr on each ip frag while socket is corked
210 */
211 struct inet_sock {
212 /* sk and pinet6 has to be the first two members of inet_sock */
213 struct sock sk;
214 #if IS_ENABLED(CONFIG_IPV6)
215 struct ipv6_pinfo *pinet6;
216 #endif
217 /* Socket demultiplex comparisons on incoming packets. */
218 #define inet_daddr sk.__sk_common.skc_daddr
219 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr
220 #define inet_dport sk.__sk_common.skc_dport
221 #define inet_num sk.__sk_common.skc_num
222
223 unsigned long inet_flags;
224 __be32 inet_saddr;
225 __s16 uc_ttl;
226 __be16 inet_sport;
227 struct ip_options_rcu __rcu *inet_opt;
228 atomic_t inet_id;
229
230 __u8 tos;
231 __u8 min_ttl;
232 __u8 mc_ttl;
233 __u8 pmtudisc;
234 __u8 rcv_tos;
235 __u8 convert_csum;
236 int uc_index;
237 int mc_index;
238 __be32 mc_addr;
239 u32 local_port_range; /* high << 16 | low */
240
241 struct ip_mc_socklist __rcu *mc_list;
242 struct inet_cork_full cork;
243 };
244
245 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */
246 #define IPCORK_TS_OPT_ID 2 /* ts_opt_id field is valid, overriding sk_tskey */
247
248 enum {
249 INET_FLAGS_PKTINFO = 0,
250 INET_FLAGS_TTL = 1,
251 INET_FLAGS_TOS = 2,
252 INET_FLAGS_RECVOPTS = 3,
253 INET_FLAGS_RETOPTS = 4,
254 INET_FLAGS_PASSSEC = 5,
255 INET_FLAGS_ORIGDSTADDR = 6,
256 INET_FLAGS_CHECKSUM = 7,
257 INET_FLAGS_RECVFRAGSIZE = 8,
258
259 INET_FLAGS_RECVERR = 9,
260 INET_FLAGS_RECVERR_RFC4884 = 10,
261 INET_FLAGS_FREEBIND = 11,
262 INET_FLAGS_HDRINCL = 12,
263 INET_FLAGS_MC_LOOP = 13,
264 INET_FLAGS_MC_ALL = 14,
265 INET_FLAGS_TRANSPARENT = 15,
266 INET_FLAGS_IS_ICSK = 16,
267 INET_FLAGS_NODEFRAG = 17,
268 INET_FLAGS_BIND_ADDRESS_NO_PORT = 18,
269 INET_FLAGS_DEFER_CONNECT = 19,
270 INET_FLAGS_MC6_LOOP = 20,
271 INET_FLAGS_RECVERR6_RFC4884 = 21,
272 INET_FLAGS_MC6_ALL = 22,
273 INET_FLAGS_AUTOFLOWLABEL_SET = 23,
274 INET_FLAGS_AUTOFLOWLABEL = 24,
275 INET_FLAGS_DONTFRAG = 25,
276 INET_FLAGS_RECVERR6 = 26,
277 INET_FLAGS_REPFLOW = 27,
278 INET_FLAGS_RTALERT_ISOLATE = 28,
279 INET_FLAGS_SNDFLOW = 29,
280 INET_FLAGS_RTALERT = 30,
281 };
282
283 /* cmsg flags for inet */
284 #define IP_CMSG_PKTINFO BIT(INET_FLAGS_PKTINFO)
285 #define IP_CMSG_TTL BIT(INET_FLAGS_TTL)
286 #define IP_CMSG_TOS BIT(INET_FLAGS_TOS)
287 #define IP_CMSG_RECVOPTS BIT(INET_FLAGS_RECVOPTS)
288 #define IP_CMSG_RETOPTS BIT(INET_FLAGS_RETOPTS)
289 #define IP_CMSG_PASSSEC BIT(INET_FLAGS_PASSSEC)
290 #define IP_CMSG_ORIGDSTADDR BIT(INET_FLAGS_ORIGDSTADDR)
291 #define IP_CMSG_CHECKSUM BIT(INET_FLAGS_CHECKSUM)
292 #define IP_CMSG_RECVFRAGSIZE BIT(INET_FLAGS_RECVFRAGSIZE)
293
294 #define IP_CMSG_ALL (IP_CMSG_PKTINFO | IP_CMSG_TTL | \
295 IP_CMSG_TOS | IP_CMSG_RECVOPTS | \
296 IP_CMSG_RETOPTS | IP_CMSG_PASSSEC | \
297 IP_CMSG_ORIGDSTADDR | IP_CMSG_CHECKSUM | \
298 IP_CMSG_RECVFRAGSIZE)
299
inet_cmsg_flags(const struct inet_sock * inet)300 static inline unsigned long inet_cmsg_flags(const struct inet_sock *inet)
301 {
302 return READ_ONCE(inet->inet_flags) & IP_CMSG_ALL;
303 }
304
305 #define inet_test_bit(nr, sk) \
306 test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
307 #define inet_set_bit(nr, sk) \
308 set_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
309 #define inet_clear_bit(nr, sk) \
310 clear_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
311 #define inet_assign_bit(nr, sk, val) \
312 assign_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags, val)
313
314 /**
315 * sk_to_full_sk - Access to a full socket
316 * @sk: pointer to a socket
317 *
318 * SYNACK messages might be attached to request sockets.
319 * Some places want to reach the listener in this case.
320 */
sk_to_full_sk(struct sock * sk)321 static inline struct sock *sk_to_full_sk(struct sock *sk)
322 {
323 #ifdef CONFIG_INET
324 if (sk && READ_ONCE(sk->sk_state) == TCP_NEW_SYN_RECV)
325 sk = inet_reqsk(sk)->rsk_listener;
326 if (sk && READ_ONCE(sk->sk_state) == TCP_TIME_WAIT)
327 sk = NULL;
328 #endif
329 return sk;
330 }
331
332 /* sk_to_full_sk() variant with a const argument */
sk_const_to_full_sk(const struct sock * sk)333 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk)
334 {
335 #ifdef CONFIG_INET
336 if (sk && READ_ONCE(sk->sk_state) == TCP_NEW_SYN_RECV)
337 sk = ((const struct request_sock *)sk)->rsk_listener;
338 if (sk && READ_ONCE(sk->sk_state) == TCP_TIME_WAIT)
339 sk = NULL;
340 #endif
341 return sk;
342 }
343
skb_to_full_sk(const struct sk_buff * skb)344 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
345 {
346 return sk_to_full_sk(skb->sk);
347 }
348
349 #define inet_sk(ptr) container_of_const(ptr, struct inet_sock, sk)
350
__inet_sk_copy_descendant(struct sock * sk_to,const struct sock * sk_from,const int ancestor_size)351 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
352 const struct sock *sk_from,
353 const int ancestor_size)
354 {
355 memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
356 sk_from->sk_prot->obj_size - ancestor_size);
357 }
358
359 int inet_sk_rebuild_header(struct sock *sk);
360
361 /**
362 * inet_sk_state_load - read sk->sk_state for lockless contexts
363 * @sk: socket pointer
364 *
365 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock:
366 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ...
367 */
inet_sk_state_load(const struct sock * sk)368 static inline int inet_sk_state_load(const struct sock *sk)
369 {
370 /* state change might impact lockless readers. */
371 return smp_load_acquire(&sk->sk_state);
372 }
373
374 /**
375 * inet_sk_state_store - update sk->sk_state
376 * @sk: socket pointer
377 * @newstate: new state
378 *
379 * Paired with inet_sk_state_load(). Should be used in contexts where
380 * state change might impact lockless readers.
381 */
382 void inet_sk_state_store(struct sock *sk, int newstate);
383
384 void inet_sk_set_state(struct sock *sk, int state);
385
__inet_ehashfn(const __be32 laddr,const __u16 lport,const __be32 faddr,const __be16 fport,u32 initval)386 static inline unsigned int __inet_ehashfn(const __be32 laddr,
387 const __u16 lport,
388 const __be32 faddr,
389 const __be16 fport,
390 u32 initval)
391 {
392 return jhash_3words((__force __u32) laddr,
393 (__force __u32) faddr,
394 ((__u32) lport) << 16 | (__force __u32)fport,
395 initval);
396 }
397
398 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
399 struct sock *sk_listener,
400 bool attach_listener);
401
inet_sk_flowi_flags(const struct sock * sk)402 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
403 {
404 __u8 flags = 0;
405
406 if (inet_test_bit(TRANSPARENT, sk) || inet_test_bit(HDRINCL, sk))
407 flags |= FLOWI_FLAG_ANYSRC;
408 return flags;
409 }
410
inet_inc_convert_csum(struct sock * sk)411 static inline void inet_inc_convert_csum(struct sock *sk)
412 {
413 inet_sk(sk)->convert_csum++;
414 }
415
inet_dec_convert_csum(struct sock * sk)416 static inline void inet_dec_convert_csum(struct sock *sk)
417 {
418 if (inet_sk(sk)->convert_csum > 0)
419 inet_sk(sk)->convert_csum--;
420 }
421
inet_get_convert_csum(struct sock * sk)422 static inline bool inet_get_convert_csum(struct sock *sk)
423 {
424 return !!inet_sk(sk)->convert_csum;
425 }
426
427
inet_can_nonlocal_bind(struct net * net,struct inet_sock * inet)428 static inline bool inet_can_nonlocal_bind(struct net *net,
429 struct inet_sock *inet)
430 {
431 return READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind) ||
432 test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) ||
433 test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags);
434 }
435
inet_addr_valid_or_nonlocal(struct net * net,struct inet_sock * inet,__be32 addr,int addr_type)436 static inline bool inet_addr_valid_or_nonlocal(struct net *net,
437 struct inet_sock *inet,
438 __be32 addr,
439 int addr_type)
440 {
441 return inet_can_nonlocal_bind(net, inet) ||
442 addr == htonl(INADDR_ANY) ||
443 addr_type == RTN_LOCAL ||
444 addr_type == RTN_MULTICAST ||
445 addr_type == RTN_BROADCAST;
446 }
447
448 #endif /* _INET_SOCK_H */
449