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 /** struct ip_options - IP Options 30 * 31 * @faddr - Saved first hop address 32 * @nexthop - Saved nexthop address in LSRR and SSRR 33 * @is_strictroute - Strict source route 34 * @srr_is_hit - Packet destination addr was our one 35 * @is_changed - IP checksum more not valid 36 * @rr_needaddr - Need to record addr of outgoing dev 37 * @ts_needtime - Need to record timestamp 38 * @ts_needaddr - Need to record addr of outgoing dev 39 */ 40 struct ip_options { 41 __be32 faddr; 42 __be32 nexthop; 43 unsigned char optlen; 44 unsigned char srr; 45 unsigned char rr; 46 unsigned char ts; 47 unsigned char is_strictroute:1, 48 srr_is_hit:1, 49 is_changed:1, 50 rr_needaddr:1, 51 ts_needtime:1, 52 ts_needaddr:1; 53 unsigned char router_alert; 54 unsigned char cipso; 55 unsigned char __pad2; 56 unsigned char __data[]; 57 }; 58 59 struct ip_options_rcu { 60 struct rcu_head rcu; 61 struct ip_options opt; 62 }; 63 64 struct ip_options_data { 65 struct ip_options_rcu opt; 66 char data[40]; 67 }; 68 69 struct inet_request_sock { 70 struct request_sock req; 71 #define ir_loc_addr req.__req_common.skc_rcv_saddr 72 #define ir_rmt_addr req.__req_common.skc_daddr 73 #define ir_num req.__req_common.skc_num 74 #define ir_rmt_port req.__req_common.skc_dport 75 #define ir_v6_rmt_addr req.__req_common.skc_v6_daddr 76 #define ir_v6_loc_addr req.__req_common.skc_v6_rcv_saddr 77 #define ir_iif req.__req_common.skc_bound_dev_if 78 #define ir_cookie req.__req_common.skc_cookie 79 #define ireq_net req.__req_common.skc_net 80 #define ireq_state req.__req_common.skc_state 81 #define ireq_family req.__req_common.skc_family 82 83 u16 snd_wscale : 4, 84 rcv_wscale : 4, 85 tstamp_ok : 1, 86 sack_ok : 1, 87 wscale_ok : 1, 88 ecn_ok : 1, 89 acked : 1, 90 no_srccheck: 1, 91 smc_ok : 1; 92 u32 ir_mark; 93 union { 94 struct ip_options_rcu __rcu *ireq_opt; 95 #if IS_ENABLED(CONFIG_IPV6) 96 struct { 97 struct ipv6_txoptions *ipv6_opt; 98 struct sk_buff *pktopts; 99 }; 100 #endif 101 }; 102 }; 103 104 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk) 105 { 106 return (struct inet_request_sock *)sk; 107 } 108 109 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb) 110 { 111 u32 mark = READ_ONCE(sk->sk_mark); 112 113 if (!mark && READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)) 114 return skb->mark; 115 116 return mark; 117 } 118 119 static inline int inet_request_bound_dev_if(const struct sock *sk, 120 struct sk_buff *skb) 121 { 122 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 123 #ifdef CONFIG_NET_L3_MASTER_DEV 124 struct net *net = sock_net(sk); 125 126 if (!bound_dev_if && READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept)) 127 return l3mdev_master_ifindex_by_index(net, skb->skb_iif); 128 #endif 129 130 return bound_dev_if; 131 } 132 133 static inline int inet_sk_bound_l3mdev(const struct sock *sk) 134 { 135 #ifdef CONFIG_NET_L3_MASTER_DEV 136 struct net *net = sock_net(sk); 137 138 if (!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept)) 139 return l3mdev_master_ifindex_by_index(net, 140 sk->sk_bound_dev_if); 141 #endif 142 143 return 0; 144 } 145 146 static inline bool inet_bound_dev_eq(bool l3mdev_accept, int bound_dev_if, 147 int dif, int sdif) 148 { 149 if (!bound_dev_if) 150 return !sdif || l3mdev_accept; 151 return bound_dev_if == dif || bound_dev_if == sdif; 152 } 153 154 static inline bool inet_sk_bound_dev_eq(const struct net *net, 155 int bound_dev_if, 156 int dif, int sdif) 157 { 158 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 159 return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept), 160 bound_dev_if, dif, sdif); 161 #else 162 return inet_bound_dev_eq(true, bound_dev_if, dif, sdif); 163 #endif 164 } 165 166 struct inet_cork { 167 unsigned int flags; 168 __be32 addr; 169 struct ip_options *opt; 170 unsigned int fragsize; 171 int length; /* Total length of all frames */ 172 struct dst_entry *dst; 173 u8 tx_flags; 174 __u8 ttl; 175 __s16 tos; 176 u32 priority; 177 __u16 gso_size; 178 u32 ts_opt_id; 179 u64 transmit_time; 180 u32 mark; 181 }; 182 183 struct inet_cork_full { 184 struct inet_cork base; 185 struct flowi fl; 186 }; 187 188 struct ip_mc_socklist; 189 struct ipv6_pinfo; 190 struct rtable; 191 192 /** struct inet_sock - representation of INET sockets 193 * 194 * @sk - ancestor class 195 * @pinet6 - pointer to IPv6 control block 196 * @inet_daddr - Foreign IPv4 addr 197 * @inet_rcv_saddr - Bound local IPv4 addr 198 * @inet_dport - Destination port 199 * @inet_num - Local port 200 * @inet_flags - various atomic flags 201 * @inet_saddr - Sending source 202 * @uc_ttl - Unicast TTL 203 * @inet_sport - Source port 204 * @inet_id - ID counter for DF pkts 205 * @tos - TOS 206 * @mc_ttl - Multicasting TTL 207 * @uc_index - Unicast outgoing device index 208 * @mc_index - Multicast device index 209 * @mc_list - Group array 210 * @cork - info to build ip hdr on each ip frag while socket is corked 211 */ 212 struct inet_sock { 213 /* sk and pinet6 has to be the first two members of inet_sock */ 214 struct sock sk; 215 #if IS_ENABLED(CONFIG_IPV6) 216 struct ipv6_pinfo *pinet6; 217 struct ipv6_fl_socklist __rcu *ipv6_fl_list; 218 #endif 219 /* Socket demultiplex comparisons on incoming packets. */ 220 #define inet_daddr sk.__sk_common.skc_daddr 221 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr 222 #define inet_dport sk.__sk_common.skc_dport 223 #define inet_num sk.__sk_common.skc_num 224 225 unsigned long inet_flags; 226 __be32 inet_saddr; 227 __s16 uc_ttl; 228 __be16 inet_sport; 229 struct ip_options_rcu __rcu *inet_opt; 230 atomic_t inet_id; 231 232 __u8 tos; 233 __u8 min_ttl; 234 __u8 mc_ttl; 235 __u8 pmtudisc; 236 __u8 rcv_tos; 237 __u8 convert_csum; 238 int uc_index; 239 int mc_index; 240 __be32 mc_addr; 241 u32 local_port_range; /* high << 16 | low */ 242 243 struct ip_mc_socklist __rcu *mc_list; 244 struct inet_cork_full cork; 245 }; 246 247 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */ 248 #define IPCORK_TS_OPT_ID 2 /* ts_opt_id field is valid, overriding sk_tskey */ 249 250 enum { 251 INET_FLAGS_PKTINFO = 0, 252 INET_FLAGS_TTL = 1, 253 INET_FLAGS_TOS = 2, 254 INET_FLAGS_RECVOPTS = 3, 255 INET_FLAGS_RETOPTS = 4, 256 INET_FLAGS_PASSSEC = 5, 257 INET_FLAGS_ORIGDSTADDR = 6, 258 INET_FLAGS_CHECKSUM = 7, 259 INET_FLAGS_RECVFRAGSIZE = 8, 260 261 INET_FLAGS_RECVERR = 9, 262 INET_FLAGS_RECVERR_RFC4884 = 10, 263 INET_FLAGS_FREEBIND = 11, 264 INET_FLAGS_HDRINCL = 12, 265 INET_FLAGS_MC_LOOP = 13, 266 INET_FLAGS_MC_ALL = 14, 267 INET_FLAGS_TRANSPARENT = 15, 268 INET_FLAGS_IS_ICSK = 16, 269 INET_FLAGS_NODEFRAG = 17, 270 INET_FLAGS_BIND_ADDRESS_NO_PORT = 18, 271 INET_FLAGS_DEFER_CONNECT = 19, 272 INET_FLAGS_MC6_LOOP = 20, 273 INET_FLAGS_RECVERR6_RFC4884 = 21, 274 INET_FLAGS_MC6_ALL = 22, 275 INET_FLAGS_AUTOFLOWLABEL_SET = 23, 276 INET_FLAGS_AUTOFLOWLABEL = 24, 277 INET_FLAGS_DONTFRAG = 25, 278 INET_FLAGS_RECVERR6 = 26, 279 INET_FLAGS_REPFLOW = 27, 280 INET_FLAGS_RTALERT_ISOLATE = 28, 281 INET_FLAGS_SNDFLOW = 29, 282 INET_FLAGS_RTALERT = 30, 283 }; 284 285 /* cmsg flags for inet */ 286 #define IP_CMSG_PKTINFO BIT(INET_FLAGS_PKTINFO) 287 #define IP_CMSG_TTL BIT(INET_FLAGS_TTL) 288 #define IP_CMSG_TOS BIT(INET_FLAGS_TOS) 289 #define IP_CMSG_RECVOPTS BIT(INET_FLAGS_RECVOPTS) 290 #define IP_CMSG_RETOPTS BIT(INET_FLAGS_RETOPTS) 291 #define IP_CMSG_PASSSEC BIT(INET_FLAGS_PASSSEC) 292 #define IP_CMSG_ORIGDSTADDR BIT(INET_FLAGS_ORIGDSTADDR) 293 #define IP_CMSG_CHECKSUM BIT(INET_FLAGS_CHECKSUM) 294 #define IP_CMSG_RECVFRAGSIZE BIT(INET_FLAGS_RECVFRAGSIZE) 295 296 #define IP_CMSG_ALL (IP_CMSG_PKTINFO | IP_CMSG_TTL | \ 297 IP_CMSG_TOS | IP_CMSG_RECVOPTS | \ 298 IP_CMSG_RETOPTS | IP_CMSG_PASSSEC | \ 299 IP_CMSG_ORIGDSTADDR | IP_CMSG_CHECKSUM | \ 300 IP_CMSG_RECVFRAGSIZE) 301 302 static inline unsigned long inet_cmsg_flags(const struct inet_sock *inet) 303 { 304 return READ_ONCE(inet->inet_flags) & IP_CMSG_ALL; 305 } 306 307 static inline dscp_t inet_sk_dscp(const struct inet_sock *inet) 308 { 309 return inet_dsfield_to_dscp(READ_ONCE(inet->tos)); 310 } 311 312 #define inet_test_bit(nr, sk) \ 313 test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 314 #define inet_set_bit(nr, sk) \ 315 set_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 316 #define inet_clear_bit(nr, sk) \ 317 clear_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags) 318 #define inet_assign_bit(nr, sk, val) \ 319 assign_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags, val) 320 321 /** 322 * sk_to_full_sk - Access to a full socket 323 * @sk: pointer to a socket 324 * 325 * SYNACK messages might be attached to request sockets. 326 * Some places want to reach the listener in this case. 327 */ 328 static inline struct sock *sk_to_full_sk(struct sock *sk) 329 { 330 #ifdef CONFIG_INET 331 if (sk && READ_ONCE(sk->sk_state) == TCP_NEW_SYN_RECV) 332 sk = inet_reqsk(sk)->rsk_listener; 333 if (sk && READ_ONCE(sk->sk_state) == TCP_TIME_WAIT) 334 sk = NULL; 335 #endif 336 return sk; 337 } 338 339 /* sk_to_full_sk() variant with a const argument */ 340 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk) 341 { 342 #ifdef CONFIG_INET 343 if (sk && READ_ONCE(sk->sk_state) == TCP_NEW_SYN_RECV) 344 sk = ((const struct request_sock *)sk)->rsk_listener; 345 if (sk && READ_ONCE(sk->sk_state) == TCP_TIME_WAIT) 346 sk = NULL; 347 #endif 348 return sk; 349 } 350 351 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb) 352 { 353 return sk_to_full_sk(skb->sk); 354 } 355 356 #define inet_sk(ptr) container_of_const(ptr, struct inet_sock, sk) 357 358 int inet_sk_rebuild_header(struct sock *sk); 359 360 /** 361 * inet_sk_state_load - read sk->sk_state for lockless contexts 362 * @sk: socket pointer 363 * 364 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock: 365 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... 366 */ 367 static inline int inet_sk_state_load(const struct sock *sk) 368 { 369 /* state change might impact lockless readers. */ 370 return smp_load_acquire(&sk->sk_state); 371 } 372 373 /** 374 * inet_sk_state_store - update sk->sk_state 375 * @sk: socket pointer 376 * @newstate: new state 377 * 378 * Paired with inet_sk_state_load(). Should be used in contexts where 379 * state change might impact lockless readers. 380 */ 381 void inet_sk_state_store(struct sock *sk, int newstate); 382 383 void inet_sk_set_state(struct sock *sk, int state); 384 385 static inline unsigned int __inet_ehashfn(const __be32 laddr, 386 const __u16 lport, 387 const __be32 faddr, 388 const __be16 fport, 389 u32 initval) 390 { 391 return jhash_3words((__force __u32) laddr, 392 (__force __u32) faddr, 393 ((__u32) lport) << 16 | (__force __u32)fport, 394 initval); 395 } 396 397 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, 398 struct sock *sk_listener, 399 bool attach_listener); 400 401 static inline __u8 inet_sk_flowi_flags(const struct sock *sk) 402 { 403 __u8 flags = 0; 404 405 if (inet_test_bit(TRANSPARENT, sk) || inet_test_bit(HDRINCL, sk)) 406 flags |= FLOWI_FLAG_ANYSRC; 407 return flags; 408 } 409 410 static inline void inet_inc_convert_csum(struct sock *sk) 411 { 412 inet_sk(sk)->convert_csum++; 413 } 414 415 static inline void inet_dec_convert_csum(struct sock *sk) 416 { 417 if (inet_sk(sk)->convert_csum > 0) 418 inet_sk(sk)->convert_csum--; 419 } 420 421 static inline bool inet_get_convert_csum(struct sock *sk) 422 { 423 return !!inet_sk(sk)->convert_csum; 424 } 425 426 427 static inline bool inet_can_nonlocal_bind(struct net *net, 428 struct inet_sock *inet) 429 { 430 return READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind) || 431 test_bit(INET_FLAGS_FREEBIND, &inet->inet_flags) || 432 test_bit(INET_FLAGS_TRANSPARENT, &inet->inet_flags); 433 } 434 435 static inline bool inet_addr_valid_or_nonlocal(struct net *net, 436 struct inet_sock *inet, 437 __be32 addr, 438 int addr_type) 439 { 440 return inet_can_nonlocal_bind(net, inet) || 441 addr == htonl(INADDR_ANY) || 442 addr_type == RTN_LOCAL || 443 addr_type == RTN_MULTICAST || 444 addr_type == RTN_BROADCAST; 445 } 446 447 #endif /* _INET_SOCK_H */ 448