1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Definitions for inet_sock 7 * 8 * Authors: Many, reorganised here by 9 * Arnaldo Carvalho de Melo <acme@mandriva.com> 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License 13 * as published by the Free Software Foundation; either version 14 * 2 of the License, or (at your option) any later version. 15 */ 16 #ifndef _INET_SOCK_H 17 #define _INET_SOCK_H 18 19 #include <linux/bitops.h> 20 #include <linux/string.h> 21 #include <linux/types.h> 22 #include <linux/jhash.h> 23 #include <linux/netdevice.h> 24 25 #include <net/flow.h> 26 #include <net/sock.h> 27 #include <net/request_sock.h> 28 #include <net/netns/hash.h> 29 #include <net/tcp_states.h> 30 #include <net/l3mdev.h> 31 32 /** struct ip_options - IP Options 33 * 34 * @faddr - Saved first hop address 35 * @nexthop - Saved nexthop address in LSRR and SSRR 36 * @is_strictroute - Strict source route 37 * @srr_is_hit - Packet destination addr was our one 38 * @is_changed - IP checksum more not valid 39 * @rr_needaddr - Need to record addr of outgoing dev 40 * @ts_needtime - Need to record timestamp 41 * @ts_needaddr - Need to record addr of outgoing dev 42 */ 43 struct ip_options { 44 __be32 faddr; 45 __be32 nexthop; 46 unsigned char optlen; 47 unsigned char srr; 48 unsigned char rr; 49 unsigned char ts; 50 unsigned char is_strictroute:1, 51 srr_is_hit:1, 52 is_changed:1, 53 rr_needaddr:1, 54 ts_needtime:1, 55 ts_needaddr:1; 56 unsigned char router_alert; 57 unsigned char cipso; 58 unsigned char __pad2; 59 unsigned char __data[0]; 60 }; 61 62 struct ip_options_rcu { 63 struct rcu_head rcu; 64 struct ip_options opt; 65 }; 66 67 struct ip_options_data { 68 struct ip_options_rcu opt; 69 char data[40]; 70 }; 71 72 struct inet_request_sock { 73 struct request_sock req; 74 #define ir_loc_addr req.__req_common.skc_rcv_saddr 75 #define ir_rmt_addr req.__req_common.skc_daddr 76 #define ir_num req.__req_common.skc_num 77 #define ir_rmt_port req.__req_common.skc_dport 78 #define ir_v6_rmt_addr req.__req_common.skc_v6_daddr 79 #define ir_v6_loc_addr req.__req_common.skc_v6_rcv_saddr 80 #define ir_iif req.__req_common.skc_bound_dev_if 81 #define ir_cookie req.__req_common.skc_cookie 82 #define ireq_net req.__req_common.skc_net 83 #define ireq_state req.__req_common.skc_state 84 #define ireq_family req.__req_common.skc_family 85 86 u16 snd_wscale : 4, 87 rcv_wscale : 4, 88 tstamp_ok : 1, 89 sack_ok : 1, 90 wscale_ok : 1, 91 ecn_ok : 1, 92 acked : 1, 93 no_srccheck: 1, 94 smc_ok : 1; 95 u32 ir_mark; 96 union { 97 struct ip_options_rcu __rcu *ireq_opt; 98 #if IS_ENABLED(CONFIG_IPV6) 99 struct { 100 struct ipv6_txoptions *ipv6_opt; 101 struct sk_buff *pktopts; 102 }; 103 #endif 104 }; 105 }; 106 107 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk) 108 { 109 return (struct inet_request_sock *)sk; 110 } 111 112 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb) 113 { 114 if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept) 115 return skb->mark; 116 117 return sk->sk_mark; 118 } 119 120 static inline int inet_request_bound_dev_if(const struct sock *sk, 121 struct sk_buff *skb) 122 { 123 #ifdef CONFIG_NET_L3_MASTER_DEV 124 struct net *net = sock_net(sk); 125 126 if (!sk->sk_bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept) 127 return l3mdev_master_ifindex_by_index(net, skb->skb_iif); 128 #endif 129 130 return sk->sk_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 (!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 struct inet_cork { 155 unsigned int flags; 156 __be32 addr; 157 struct ip_options *opt; 158 unsigned int fragsize; 159 int length; /* Total length of all frames */ 160 struct dst_entry *dst; 161 u8 tx_flags; 162 __u8 ttl; 163 __s16 tos; 164 char priority; 165 __u16 gso_size; 166 u64 transmit_time; 167 }; 168 169 struct inet_cork_full { 170 struct inet_cork base; 171 struct flowi fl; 172 }; 173 174 struct ip_mc_socklist; 175 struct ipv6_pinfo; 176 struct rtable; 177 178 /** struct inet_sock - representation of INET sockets 179 * 180 * @sk - ancestor class 181 * @pinet6 - pointer to IPv6 control block 182 * @inet_daddr - Foreign IPv4 addr 183 * @inet_rcv_saddr - Bound local IPv4 addr 184 * @inet_dport - Destination port 185 * @inet_num - Local port 186 * @inet_saddr - Sending source 187 * @uc_ttl - Unicast TTL 188 * @inet_sport - Source port 189 * @inet_id - ID counter for DF pkts 190 * @tos - TOS 191 * @mc_ttl - Multicasting TTL 192 * @is_icsk - is this an inet_connection_sock? 193 * @uc_index - Unicast outgoing device index 194 * @mc_index - Multicast device index 195 * @mc_list - Group array 196 * @cork - info to build ip hdr on each ip frag while socket is corked 197 */ 198 struct inet_sock { 199 /* sk and pinet6 has to be the first two members of inet_sock */ 200 struct sock sk; 201 #if IS_ENABLED(CONFIG_IPV6) 202 struct ipv6_pinfo *pinet6; 203 #endif 204 /* Socket demultiplex comparisons on incoming packets. */ 205 #define inet_daddr sk.__sk_common.skc_daddr 206 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr 207 #define inet_dport sk.__sk_common.skc_dport 208 #define inet_num sk.__sk_common.skc_num 209 210 __be32 inet_saddr; 211 __s16 uc_ttl; 212 __u16 cmsg_flags; 213 __be16 inet_sport; 214 __u16 inet_id; 215 216 struct ip_options_rcu __rcu *inet_opt; 217 int rx_dst_ifindex; 218 __u8 tos; 219 __u8 min_ttl; 220 __u8 mc_ttl; 221 __u8 pmtudisc; 222 __u8 recverr:1, 223 is_icsk:1, 224 freebind:1, 225 hdrincl:1, 226 mc_loop:1, 227 transparent:1, 228 mc_all:1, 229 nodefrag:1; 230 __u8 bind_address_no_port:1, 231 defer_connect:1; /* Indicates that fastopen_connect is set 232 * and cookie exists so we defer connect 233 * until first data frame is written 234 */ 235 __u8 rcv_tos; 236 __u8 convert_csum; 237 int uc_index; 238 int mc_index; 239 __be32 mc_addr; 240 struct ip_mc_socklist __rcu *mc_list; 241 struct inet_cork_full cork; 242 }; 243 244 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */ 245 #define IPCORK_ALLFRAG 2 /* always fragment (for ipv6 for now) */ 246 247 /* cmsg flags for inet */ 248 #define IP_CMSG_PKTINFO BIT(0) 249 #define IP_CMSG_TTL BIT(1) 250 #define IP_CMSG_TOS BIT(2) 251 #define IP_CMSG_RECVOPTS BIT(3) 252 #define IP_CMSG_RETOPTS BIT(4) 253 #define IP_CMSG_PASSSEC BIT(5) 254 #define IP_CMSG_ORIGDSTADDR BIT(6) 255 #define IP_CMSG_CHECKSUM BIT(7) 256 #define IP_CMSG_RECVFRAGSIZE BIT(8) 257 258 /** 259 * sk_to_full_sk - Access to a full socket 260 * @sk: pointer to a socket 261 * 262 * SYNACK messages might be attached to request sockets. 263 * Some places want to reach the listener in this case. 264 */ 265 static inline struct sock *sk_to_full_sk(struct sock *sk) 266 { 267 #ifdef CONFIG_INET 268 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 269 sk = inet_reqsk(sk)->rsk_listener; 270 #endif 271 return sk; 272 } 273 274 /* sk_to_full_sk() variant with a const argument */ 275 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk) 276 { 277 #ifdef CONFIG_INET 278 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 279 sk = ((const struct request_sock *)sk)->rsk_listener; 280 #endif 281 return sk; 282 } 283 284 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb) 285 { 286 return sk_to_full_sk(skb->sk); 287 } 288 289 static inline struct inet_sock *inet_sk(const struct sock *sk) 290 { 291 return (struct inet_sock *)sk; 292 } 293 294 static inline void __inet_sk_copy_descendant(struct sock *sk_to, 295 const struct sock *sk_from, 296 const int ancestor_size) 297 { 298 memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1, 299 sk_from->sk_prot->obj_size - ancestor_size); 300 } 301 #if !(IS_ENABLED(CONFIG_IPV6)) 302 static inline void inet_sk_copy_descendant(struct sock *sk_to, 303 const struct sock *sk_from) 304 { 305 __inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock)); 306 } 307 #endif 308 309 int inet_sk_rebuild_header(struct sock *sk); 310 311 /** 312 * inet_sk_state_load - read sk->sk_state for lockless contexts 313 * @sk: socket pointer 314 * 315 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock: 316 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... 317 */ 318 static inline int inet_sk_state_load(const struct sock *sk) 319 { 320 /* state change might impact lockless readers. */ 321 return smp_load_acquire(&sk->sk_state); 322 } 323 324 /** 325 * inet_sk_state_store - update sk->sk_state 326 * @sk: socket pointer 327 * @newstate: new state 328 * 329 * Paired with inet_sk_state_load(). Should be used in contexts where 330 * state change might impact lockless readers. 331 */ 332 void inet_sk_state_store(struct sock *sk, int newstate); 333 334 void inet_sk_set_state(struct sock *sk, int state); 335 336 static inline unsigned int __inet_ehashfn(const __be32 laddr, 337 const __u16 lport, 338 const __be32 faddr, 339 const __be16 fport, 340 u32 initval) 341 { 342 return jhash_3words((__force __u32) laddr, 343 (__force __u32) faddr, 344 ((__u32) lport) << 16 | (__force __u32)fport, 345 initval); 346 } 347 348 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, 349 struct sock *sk_listener, 350 bool attach_listener); 351 352 static inline __u8 inet_sk_flowi_flags(const struct sock *sk) 353 { 354 __u8 flags = 0; 355 356 if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl) 357 flags |= FLOWI_FLAG_ANYSRC; 358 return flags; 359 } 360 361 static inline void inet_inc_convert_csum(struct sock *sk) 362 { 363 inet_sk(sk)->convert_csum++; 364 } 365 366 static inline void inet_dec_convert_csum(struct sock *sk) 367 { 368 if (inet_sk(sk)->convert_csum > 0) 369 inet_sk(sk)->convert_csum--; 370 } 371 372 static inline bool inet_get_convert_csum(struct sock *sk) 373 { 374 return !!inet_sk(sk)->convert_csum; 375 } 376 377 378 static inline bool inet_can_nonlocal_bind(struct net *net, 379 struct inet_sock *inet) 380 { 381 return net->ipv4.sysctl_ip_nonlocal_bind || 382 inet->freebind || inet->transparent; 383 } 384 385 #endif /* _INET_SOCK_H */ 386