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 }; 278 279 /* cmsg flags for inet */ 280 #define IP_CMSG_PKTINFO BIT(INET_FLAGS_PKTINFO) 281 #define IP_CMSG_TTL BIT(INET_FLAGS_TTL) 282 #define IP_CMSG_TOS BIT(INET_FLAGS_TOS) 283 #define IP_CMSG_RECVOPTS BIT(INET_FLAGS_RECVOPTS) 284 #define IP_CMSG_RETOPTS BIT(INET_FLAGS_RETOPTS) 285 #define IP_CMSG_PASSSEC BIT(INET_FLAGS_PASSSEC) 286 #define IP_CMSG_ORIGDSTADDR BIT(INET_FLAGS_ORIGDSTADDR) 287 #define IP_CMSG_CHECKSUM BIT(INET_FLAGS_CHECKSUM) 288 #define IP_CMSG_RECVFRAGSIZE BIT(INET_FLAGS_RECVFRAGSIZE) 289 290 #define IP_CMSG_ALL (IP_CMSG_PKTINFO | IP_CMSG_TTL | \ 291 IP_CMSG_TOS | IP_CMSG_RECVOPTS | \ 292 IP_CMSG_RETOPTS | IP_CMSG_PASSSEC | \ 293 IP_CMSG_ORIGDSTADDR | IP_CMSG_CHECKSUM | \ 294 IP_CMSG_RECVFRAGSIZE) 295 296 static inline unsigned long inet_cmsg_flags(const struct inet_sock *inet) 297 { 298 return READ_ONCE(inet->inet_flags) & IP_CMSG_ALL; 299 } 300 301 #define inet_test_bit(nr, sk) \ 302 test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 303 #define inet_set_bit(nr, sk) \ 304 set_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 305 #define inet_clear_bit(nr, sk) \ 306 clear_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 307 #define inet_assign_bit(nr, sk, val) \ 308 assign_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags, val) 309 310 /** 311 * sk_to_full_sk - Access to a full socket 312 * @sk: pointer to a socket 313 * 314 * SYNACK messages might be attached to request sockets. 315 * Some places want to reach the listener in this case. 316 */ 317 static inline struct sock *sk_to_full_sk(struct sock *sk) 318 { 319 #ifdef CONFIG_INET 320 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 321 sk = inet_reqsk(sk)->rsk_listener; 322 #endif 323 return sk; 324 } 325 326 /* sk_to_full_sk() variant with a const argument */ 327 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk) 328 { 329 #ifdef CONFIG_INET 330 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 331 sk = ((const struct request_sock *)sk)->rsk_listener; 332 #endif 333 return sk; 334 } 335 336 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb) 337 { 338 return sk_to_full_sk(skb->sk); 339 } 340 341 #define inet_sk(ptr) container_of_const(ptr, struct inet_sock, sk) 342 343 static inline void __inet_sk_copy_descendant(struct sock *sk_to, 344 const struct sock *sk_from, 345 const int ancestor_size) 346 { 347 memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1, 348 sk_from->sk_prot->obj_size - ancestor_size); 349 } 350 351 int inet_sk_rebuild_header(struct sock *sk); 352 353 /** 354 * inet_sk_state_load - read sk->sk_state for lockless contexts 355 * @sk: socket pointer 356 * 357 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock: 358 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... 359 */ 360 static inline int inet_sk_state_load(const struct sock *sk) 361 { 362 /* state change might impact lockless readers. */ 363 return smp_load_acquire(&sk->sk_state); 364 } 365 366 /** 367 * inet_sk_state_store - update sk->sk_state 368 * @sk: socket pointer 369 * @newstate: new state 370 * 371 * Paired with inet_sk_state_load(). Should be used in contexts where 372 * state change might impact lockless readers. 373 */ 374 void inet_sk_state_store(struct sock *sk, int newstate); 375 376 void inet_sk_set_state(struct sock *sk, int state); 377 378 static inline unsigned int __inet_ehashfn(const __be32 laddr, 379 const __u16 lport, 380 const __be32 faddr, 381 const __be16 fport, 382 u32 initval) 383 { 384 return jhash_3words((__force __u32) laddr, 385 (__force __u32) faddr, 386 ((__u32) lport) << 16 | (__force __u32)fport, 387 initval); 388 } 389 390 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, 391 struct sock *sk_listener, 392 bool attach_listener); 393 394 static inline __u8 inet_sk_flowi_flags(const struct sock *sk) 395 { 396 __u8 flags = 0; 397 398 if (inet_test_bit(TRANSPARENT, sk) || inet_test_bit(HDRINCL, sk)) 399 flags |= FLOWI_FLAG_ANYSRC; 400 return flags; 401 } 402 403 static inline void inet_inc_convert_csum(struct sock *sk) 404 { 405 inet_sk(sk)->convert_csum++; 406 } 407 408 static inline void inet_dec_convert_csum(struct sock *sk) 409 { 410 if (inet_sk(sk)->convert_csum > 0) 411 inet_sk(sk)->convert_csum--; 412 } 413 414 static inline bool inet_get_convert_csum(struct sock *sk) 415 { 416 return !!inet_sk(sk)->convert_csum; 417 } 418 419 420 static inline bool inet_can_nonlocal_bind(struct net *net, 421 struct inet_sock *inet) 422 { 423 return READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind) || 424 test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) || 425 test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags); 426 } 427 428 static inline bool inet_addr_valid_or_nonlocal(struct net *net, 429 struct inet_sock *inet, 430 __be32 addr, 431 int addr_type) 432 { 433 return inet_can_nonlocal_bind(net, inet) || 434 addr == htonl(INADDR_ANY) || 435 addr_type == RTN_LOCAL || 436 addr_type == RTN_MULTICAST || 437 addr_type == RTN_BROADCAST; 438 } 439 440 #endif /* _INET_SOCK_H */ 441