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 struct ip_options_rcu *ireq_opt_deref(const struct inet_request_sock *ireq) 134 { 135 return rcu_dereference_check(ireq->ireq_opt, 136 refcount_read(&ireq->req.rsk_refcnt) > 0); 137 } 138 139 struct inet_cork { 140 unsigned int flags; 141 __be32 addr; 142 struct ip_options *opt; 143 unsigned int fragsize; 144 int length; /* Total length of all frames */ 145 struct dst_entry *dst; 146 u8 tx_flags; 147 __u8 ttl; 148 __s16 tos; 149 char priority; 150 __u16 gso_size; 151 u64 transmit_time; 152 }; 153 154 struct inet_cork_full { 155 struct inet_cork base; 156 struct flowi fl; 157 }; 158 159 struct ip_mc_socklist; 160 struct ipv6_pinfo; 161 struct rtable; 162 163 /** struct inet_sock - representation of INET sockets 164 * 165 * @sk - ancestor class 166 * @pinet6 - pointer to IPv6 control block 167 * @inet_daddr - Foreign IPv4 addr 168 * @inet_rcv_saddr - Bound local IPv4 addr 169 * @inet_dport - Destination port 170 * @inet_num - Local port 171 * @inet_saddr - Sending source 172 * @uc_ttl - Unicast TTL 173 * @inet_sport - Source port 174 * @inet_id - ID counter for DF pkts 175 * @tos - TOS 176 * @mc_ttl - Multicasting TTL 177 * @is_icsk - is this an inet_connection_sock? 178 * @uc_index - Unicast outgoing device index 179 * @mc_index - Multicast device index 180 * @mc_list - Group array 181 * @cork - info to build ip hdr on each ip frag while socket is corked 182 */ 183 struct inet_sock { 184 /* sk and pinet6 has to be the first two members of inet_sock */ 185 struct sock sk; 186 #if IS_ENABLED(CONFIG_IPV6) 187 struct ipv6_pinfo *pinet6; 188 #endif 189 /* Socket demultiplex comparisons on incoming packets. */ 190 #define inet_daddr sk.__sk_common.skc_daddr 191 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr 192 #define inet_dport sk.__sk_common.skc_dport 193 #define inet_num sk.__sk_common.skc_num 194 195 __be32 inet_saddr; 196 __s16 uc_ttl; 197 __u16 cmsg_flags; 198 __be16 inet_sport; 199 __u16 inet_id; 200 201 struct ip_options_rcu __rcu *inet_opt; 202 int rx_dst_ifindex; 203 __u8 tos; 204 __u8 min_ttl; 205 __u8 mc_ttl; 206 __u8 pmtudisc; 207 __u8 recverr:1, 208 is_icsk:1, 209 freebind:1, 210 hdrincl:1, 211 mc_loop:1, 212 transparent:1, 213 mc_all:1, 214 nodefrag:1; 215 __u8 bind_address_no_port:1, 216 defer_connect:1; /* Indicates that fastopen_connect is set 217 * and cookie exists so we defer connect 218 * until first data frame is written 219 */ 220 __u8 rcv_tos; 221 __u8 convert_csum; 222 int uc_index; 223 int mc_index; 224 __be32 mc_addr; 225 struct ip_mc_socklist __rcu *mc_list; 226 struct inet_cork_full cork; 227 }; 228 229 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */ 230 #define IPCORK_ALLFRAG 2 /* always fragment (for ipv6 for now) */ 231 232 /* cmsg flags for inet */ 233 #define IP_CMSG_PKTINFO BIT(0) 234 #define IP_CMSG_TTL BIT(1) 235 #define IP_CMSG_TOS BIT(2) 236 #define IP_CMSG_RECVOPTS BIT(3) 237 #define IP_CMSG_RETOPTS BIT(4) 238 #define IP_CMSG_PASSSEC BIT(5) 239 #define IP_CMSG_ORIGDSTADDR BIT(6) 240 #define IP_CMSG_CHECKSUM BIT(7) 241 #define IP_CMSG_RECVFRAGSIZE BIT(8) 242 243 /** 244 * sk_to_full_sk - Access to a full socket 245 * @sk: pointer to a socket 246 * 247 * SYNACK messages might be attached to request sockets. 248 * Some places want to reach the listener in this case. 249 */ 250 static inline struct sock *sk_to_full_sk(struct sock *sk) 251 { 252 #ifdef CONFIG_INET 253 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 254 sk = inet_reqsk(sk)->rsk_listener; 255 #endif 256 return sk; 257 } 258 259 /* sk_to_full_sk() variant with a const argument */ 260 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk) 261 { 262 #ifdef CONFIG_INET 263 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 264 sk = ((const struct request_sock *)sk)->rsk_listener; 265 #endif 266 return sk; 267 } 268 269 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb) 270 { 271 return sk_to_full_sk(skb->sk); 272 } 273 274 static inline struct inet_sock *inet_sk(const struct sock *sk) 275 { 276 return (struct inet_sock *)sk; 277 } 278 279 static inline void __inet_sk_copy_descendant(struct sock *sk_to, 280 const struct sock *sk_from, 281 const int ancestor_size) 282 { 283 memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1, 284 sk_from->sk_prot->obj_size - ancestor_size); 285 } 286 #if !(IS_ENABLED(CONFIG_IPV6)) 287 static inline void inet_sk_copy_descendant(struct sock *sk_to, 288 const struct sock *sk_from) 289 { 290 __inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock)); 291 } 292 #endif 293 294 int inet_sk_rebuild_header(struct sock *sk); 295 296 /** 297 * inet_sk_state_load - read sk->sk_state for lockless contexts 298 * @sk: socket pointer 299 * 300 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock: 301 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... 302 */ 303 static inline int inet_sk_state_load(const struct sock *sk) 304 { 305 /* state change might impact lockless readers. */ 306 return smp_load_acquire(&sk->sk_state); 307 } 308 309 /** 310 * inet_sk_state_store - update sk->sk_state 311 * @sk: socket pointer 312 * @newstate: new state 313 * 314 * Paired with inet_sk_state_load(). Should be used in contexts where 315 * state change might impact lockless readers. 316 */ 317 void inet_sk_state_store(struct sock *sk, int newstate); 318 319 void inet_sk_set_state(struct sock *sk, int state); 320 321 static inline unsigned int __inet_ehashfn(const __be32 laddr, 322 const __u16 lport, 323 const __be32 faddr, 324 const __be16 fport, 325 u32 initval) 326 { 327 return jhash_3words((__force __u32) laddr, 328 (__force __u32) faddr, 329 ((__u32) lport) << 16 | (__force __u32)fport, 330 initval); 331 } 332 333 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, 334 struct sock *sk_listener, 335 bool attach_listener); 336 337 static inline __u8 inet_sk_flowi_flags(const struct sock *sk) 338 { 339 __u8 flags = 0; 340 341 if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl) 342 flags |= FLOWI_FLAG_ANYSRC; 343 return flags; 344 } 345 346 static inline void inet_inc_convert_csum(struct sock *sk) 347 { 348 inet_sk(sk)->convert_csum++; 349 } 350 351 static inline void inet_dec_convert_csum(struct sock *sk) 352 { 353 if (inet_sk(sk)->convert_csum > 0) 354 inet_sk(sk)->convert_csum--; 355 } 356 357 static inline bool inet_get_convert_csum(struct sock *sk) 358 { 359 return !!inet_sk(sk)->convert_csum; 360 } 361 362 363 static inline bool inet_can_nonlocal_bind(struct net *net, 364 struct inet_sock *inet) 365 { 366 return net->ipv4.sysctl_ip_nonlocal_bind || 367 inet->freebind || inet->transparent; 368 } 369 370 #endif /* _INET_SOCK_H */ 371