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/inet_dscp.h> 23 #include <net/sock.h> 24 #include <net/request_sock.h> 25 #include <net/netns/hash.h> 26 #include <net/tcp_states.h> 27 #include <net/l3mdev.h> 28 29 #define IP_OPTIONS_DATA_FIXED_SIZE 40 30 31 /** struct ip_options - IP Options 32 * 33 * @faddr - Saved first hop address 34 * @nexthop - Saved nexthop address in LSRR and SSRR 35 * @is_strictroute - Strict source route 36 * @srr_is_hit - Packet destination addr was our one 37 * @is_changed - IP checksum more not valid 38 * @rr_needaddr - Need to record addr of outgoing dev 39 * @ts_needtime - Need to record timestamp 40 * @ts_needaddr - Need to record addr of outgoing dev 41 */ 42 struct ip_options { 43 __be32 faddr; 44 __be32 nexthop; 45 unsigned char optlen; 46 unsigned char srr; 47 unsigned char rr; 48 unsigned char ts; 49 unsigned char is_strictroute:1, 50 srr_is_hit:1, 51 is_changed:1, 52 rr_needaddr:1, 53 ts_needtime:1, 54 ts_needaddr:1; 55 unsigned char router_alert; 56 unsigned char cipso; 57 unsigned char __pad2; 58 unsigned char __data[]; 59 }; 60 61 struct ip_options_rcu { 62 struct rcu_head rcu; 63 64 /* Must be last as it ends in a flexible-array member. */ 65 struct ip_options opt; 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 #define inet_rsk(ptr) container_of_const(ptr, struct inet_request_sock, req) 104 105 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb) 106 { 107 u32 mark = READ_ONCE(sk->sk_mark); 108 109 if (!mark && READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)) 110 return skb->mark; 111 112 return mark; 113 } 114 115 static inline int inet_request_bound_dev_if(const struct sock *sk, 116 struct sk_buff *skb) 117 { 118 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 119 #ifdef CONFIG_NET_L3_MASTER_DEV 120 struct net *net = sock_net(sk); 121 122 if (!bound_dev_if && READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept)) 123 return l3mdev_master_ifindex_by_index(net, skb->skb_iif); 124 #endif 125 126 return bound_dev_if; 127 } 128 129 static inline int inet_sk_bound_l3mdev(const struct sock *sk) 130 { 131 #ifdef CONFIG_NET_L3_MASTER_DEV 132 struct net *net = sock_net(sk); 133 134 if (!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept)) 135 return l3mdev_master_ifindex_by_index(net, 136 sk->sk_bound_dev_if); 137 #endif 138 139 return 0; 140 } 141 142 static inline bool inet_bound_dev_eq(bool l3mdev_accept, int bound_dev_if, 143 int dif, int sdif) 144 { 145 if (!bound_dev_if) 146 return !sdif || l3mdev_accept; 147 return bound_dev_if == dif || bound_dev_if == sdif; 148 } 149 150 static inline bool inet_sk_bound_dev_eq(const struct net *net, 151 int bound_dev_if, 152 int dif, int sdif) 153 { 154 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 155 return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept), 156 bound_dev_if, dif, sdif); 157 #else 158 return inet_bound_dev_eq(true, bound_dev_if, dif, sdif); 159 #endif 160 } 161 162 struct inet6_cork { 163 struct ipv6_txoptions *opt; 164 u8 hop_limit; 165 u8 tclass; 166 u8 dontfrag:1; 167 }; 168 169 struct inet_cork { 170 unsigned int flags; 171 __be32 addr; 172 struct ip_options *opt; 173 unsigned int fragsize; 174 int length; /* Total length of all frames */ 175 struct dst_entry *dst; 176 u8 tx_flags; 177 __u8 ttl; 178 __s16 tos; 179 u32 priority; 180 __u16 gso_size; 181 u32 ts_opt_id; 182 u64 transmit_time; 183 u32 mark; 184 }; 185 186 struct inet_cork_full { 187 struct inet_cork base; 188 struct flowi fl; 189 #if IS_ENABLED(CONFIG_IPV6) 190 struct inet6_cork base6; 191 #endif 192 }; 193 194 struct ip_mc_socklist; 195 struct ipv6_pinfo; 196 struct rtable; 197 198 /** struct inet_sock - representation of INET sockets 199 * 200 * @sk - ancestor class 201 * @pinet6 - pointer to IPv6 control block 202 * @inet_daddr - Foreign IPv4 addr 203 * @inet_rcv_saddr - Bound local IPv4 addr 204 * @inet_dport - Destination port 205 * @inet_num - Local port 206 * @inet_flags - various atomic flags 207 * @inet_saddr - Sending source 208 * @uc_ttl - Unicast TTL 209 * @inet_sport - Source port 210 * @inet_id - ID counter for DF pkts 211 * @tos - TOS 212 * @mc_ttl - Multicasting TTL 213 * @uc_index - Unicast outgoing device index 214 * @mc_index - Multicast device index 215 * @mc_list - Group array 216 * @cork - info to build ip hdr on each ip frag while socket is corked 217 */ 218 struct inet_sock { 219 /* sk and pinet6 has to be the first two members of inet_sock */ 220 struct sock sk; 221 #if IS_ENABLED(CONFIG_IPV6) 222 struct ipv6_pinfo *pinet6; 223 struct ipv6_fl_socklist __rcu *ipv6_fl_list; 224 #endif 225 /* Socket demultiplex comparisons on incoming packets. */ 226 #define inet_daddr sk.__sk_common.skc_daddr 227 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr 228 #define inet_dport sk.__sk_common.skc_dport 229 #define inet_num sk.__sk_common.skc_num 230 231 unsigned long inet_flags; 232 __be32 inet_saddr; 233 __s16 uc_ttl; 234 __be16 inet_sport; 235 struct ip_options_rcu __rcu *inet_opt; 236 atomic_t inet_id; 237 238 __u8 tos; 239 __u8 min_ttl; 240 __u8 mc_ttl; 241 __u8 pmtudisc; 242 __u8 rcv_tos; 243 __u8 convert_csum; 244 int uc_index; 245 int mc_index; 246 __be32 mc_addr; 247 u32 local_port_range; /* high << 16 | low */ 248 249 struct ip_mc_socklist __rcu *mc_list; 250 struct inet_cork_full cork; 251 }; 252 253 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */ 254 #define IPCORK_TS_OPT_ID 2 /* ts_opt_id field is valid, overriding sk_tskey */ 255 256 enum { 257 INET_FLAGS_PKTINFO = 0, 258 INET_FLAGS_TTL = 1, 259 INET_FLAGS_TOS = 2, 260 INET_FLAGS_RECVOPTS = 3, 261 INET_FLAGS_RETOPTS = 4, 262 INET_FLAGS_PASSSEC = 5, 263 INET_FLAGS_ORIGDSTADDR = 6, 264 INET_FLAGS_CHECKSUM = 7, 265 INET_FLAGS_RECVFRAGSIZE = 8, 266 267 INET_FLAGS_RECVERR = 9, 268 INET_FLAGS_RECVERR_RFC4884 = 10, 269 INET_FLAGS_FREEBIND = 11, 270 INET_FLAGS_HDRINCL = 12, 271 INET_FLAGS_MC_LOOP = 13, 272 INET_FLAGS_MC_ALL = 14, 273 INET_FLAGS_TRANSPARENT = 15, 274 INET_FLAGS_IS_ICSK = 16, 275 INET_FLAGS_NODEFRAG = 17, 276 INET_FLAGS_BIND_ADDRESS_NO_PORT = 18, 277 INET_FLAGS_DEFER_CONNECT = 19, 278 INET_FLAGS_MC6_LOOP = 20, 279 INET_FLAGS_RECVERR6_RFC4884 = 21, 280 INET_FLAGS_MC6_ALL = 22, 281 INET_FLAGS_AUTOFLOWLABEL_SET = 23, 282 INET_FLAGS_AUTOFLOWLABEL = 24, 283 INET_FLAGS_DONTFRAG = 25, 284 INET_FLAGS_RECVERR6 = 26, 285 INET_FLAGS_REPFLOW = 27, 286 INET_FLAGS_RTALERT_ISOLATE = 28, 287 INET_FLAGS_SNDFLOW = 29, 288 INET_FLAGS_RTALERT = 30, 289 }; 290 291 /* cmsg flags for inet */ 292 #define IP_CMSG_PKTINFO BIT(INET_FLAGS_PKTINFO) 293 #define IP_CMSG_TTL BIT(INET_FLAGS_TTL) 294 #define IP_CMSG_TOS BIT(INET_FLAGS_TOS) 295 #define IP_CMSG_RECVOPTS BIT(INET_FLAGS_RECVOPTS) 296 #define IP_CMSG_RETOPTS BIT(INET_FLAGS_RETOPTS) 297 #define IP_CMSG_PASSSEC BIT(INET_FLAGS_PASSSEC) 298 #define IP_CMSG_ORIGDSTADDR BIT(INET_FLAGS_ORIGDSTADDR) 299 #define IP_CMSG_CHECKSUM BIT(INET_FLAGS_CHECKSUM) 300 #define IP_CMSG_RECVFRAGSIZE BIT(INET_FLAGS_RECVFRAGSIZE) 301 302 #define IP_CMSG_ALL (IP_CMSG_PKTINFO | IP_CMSG_TTL | \ 303 IP_CMSG_TOS | IP_CMSG_RECVOPTS | \ 304 IP_CMSG_RETOPTS | IP_CMSG_PASSSEC | \ 305 IP_CMSG_ORIGDSTADDR | IP_CMSG_CHECKSUM | \ 306 IP_CMSG_RECVFRAGSIZE) 307 308 static inline unsigned long inet_cmsg_flags(const struct inet_sock *inet) 309 { 310 return READ_ONCE(inet->inet_flags) & IP_CMSG_ALL; 311 } 312 313 static inline dscp_t inet_sk_dscp(const struct inet_sock *inet) 314 { 315 return inet_dsfield_to_dscp(READ_ONCE(inet->tos)); 316 } 317 318 #define inet_test_bit(nr, sk) \ 319 test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 320 #define inet_set_bit(nr, sk) \ 321 set_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 322 #define inet_clear_bit(nr, sk) \ 323 clear_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 324 #define inet_assign_bit(nr, sk, val) \ 325 assign_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags, val) 326 327 /** 328 * sk_to_full_sk - Access to a full socket 329 * @sk: pointer to a socket 330 * 331 * SYNACK messages might be attached to request sockets. 332 * Some places want to reach the listener in this case. 333 */ 334 static inline struct sock *sk_to_full_sk(struct sock *sk) 335 { 336 #ifdef CONFIG_INET 337 if (sk && READ_ONCE(sk->sk_state) == TCP_NEW_SYN_RECV) 338 sk = inet_reqsk(sk)->rsk_listener; 339 if (sk && READ_ONCE(sk->sk_state) == TCP_TIME_WAIT) 340 sk = NULL; 341 #endif 342 return sk; 343 } 344 345 /* sk_to_full_sk() variant with a const argument */ 346 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk) 347 { 348 #ifdef CONFIG_INET 349 if (sk && READ_ONCE(sk->sk_state) == TCP_NEW_SYN_RECV) 350 sk = ((const struct request_sock *)sk)->rsk_listener; 351 if (sk && READ_ONCE(sk->sk_state) == TCP_TIME_WAIT) 352 sk = NULL; 353 #endif 354 return sk; 355 } 356 357 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb) 358 { 359 return sk_to_full_sk(skb->sk); 360 } 361 362 #define inet_sk(ptr) container_of_const(ptr, struct inet_sock, sk) 363 364 int inet_sk_rebuild_header(struct sock *sk); 365 366 /** 367 * inet_sk_state_load - read sk->sk_state for lockless contexts 368 * @sk: socket pointer 369 * 370 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock: 371 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... 372 */ 373 static inline int inet_sk_state_load(const struct sock *sk) 374 { 375 /* state change might impact lockless readers. */ 376 return smp_load_acquire(&sk->sk_state); 377 } 378 379 /** 380 * inet_sk_state_store - update sk->sk_state 381 * @sk: socket pointer 382 * @newstate: new state 383 * 384 * Paired with inet_sk_state_load(). Should be used in contexts where 385 * state change might impact lockless readers. 386 */ 387 void inet_sk_state_store(struct sock *sk, int newstate); 388 389 void inet_sk_set_state(struct sock *sk, int state); 390 391 static inline unsigned int __inet_ehashfn(const __be32 laddr, 392 const __u16 lport, 393 const __be32 faddr, 394 const __be16 fport, 395 u32 initval) 396 { 397 return jhash_3words((__force __u32) laddr, 398 (__force __u32) faddr, 399 ((__u32) lport) << 16 | (__force __u32)fport, 400 initval); 401 } 402 403 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, 404 struct sock *sk_listener, 405 bool attach_listener); 406 407 static inline __u8 inet_sk_flowi_flags(const struct sock *sk) 408 { 409 __u8 flags = 0; 410 411 if (inet_test_bit(TRANSPARENT, sk) || inet_test_bit(HDRINCL, sk)) 412 flags |= FLOWI_FLAG_ANYSRC; 413 return flags; 414 } 415 416 static inline void inet_inc_convert_csum(struct sock *sk) 417 { 418 inet_sk(sk)->convert_csum++; 419 } 420 421 static inline void inet_dec_convert_csum(struct sock *sk) 422 { 423 if (inet_sk(sk)->convert_csum > 0) 424 inet_sk(sk)->convert_csum--; 425 } 426 427 static inline bool inet_get_convert_csum(struct sock *sk) 428 { 429 return !!inet_sk(sk)->convert_csum; 430 } 431 432 433 static inline bool inet_can_nonlocal_bind(struct net *net, 434 struct inet_sock *inet) 435 { 436 return READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind) || 437 test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) || 438 test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags); 439 } 440 441 static inline bool inet_addr_valid_or_nonlocal(struct net *net, 442 struct inet_sock *inet, 443 __be32 addr, 444 int addr_type) 445 { 446 return inet_can_nonlocal_bind(net, inet) || 447 addr == htonl(INADDR_ANY) || 448 addr_type == RTN_LOCAL || 449 addr_type == RTN_MULTICAST || 450 addr_type == RTN_BROADCAST; 451 } 452 453 #endif /* _INET_SOCK_H */ 454