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 if (!sk->sk_mark && 111 READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)) 112 return skb->mark; 113 114 return sk->sk_mark; 115 } 116 117 static inline int inet_request_bound_dev_if(const struct sock *sk, 118 struct sk_buff *skb) 119 { 120 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 121 #ifdef CONFIG_NET_L3_MASTER_DEV 122 struct net *net = sock_net(sk); 123 124 if (!bound_dev_if && READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept)) 125 return l3mdev_master_ifindex_by_index(net, skb->skb_iif); 126 #endif 127 128 return bound_dev_if; 129 } 130 131 static inline int inet_sk_bound_l3mdev(const struct sock *sk) 132 { 133 #ifdef CONFIG_NET_L3_MASTER_DEV 134 struct net *net = sock_net(sk); 135 136 if (!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept)) 137 return l3mdev_master_ifindex_by_index(net, 138 sk->sk_bound_dev_if); 139 #endif 140 141 return 0; 142 } 143 144 static inline bool inet_bound_dev_eq(bool l3mdev_accept, int bound_dev_if, 145 int dif, int sdif) 146 { 147 if (!bound_dev_if) 148 return !sdif || l3mdev_accept; 149 return bound_dev_if == dif || bound_dev_if == sdif; 150 } 151 152 static inline bool inet_sk_bound_dev_eq(struct net *net, int bound_dev_if, 153 int dif, int sdif) 154 { 155 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 156 return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept), 157 bound_dev_if, dif, sdif); 158 #else 159 return inet_bound_dev_eq(true, bound_dev_if, dif, sdif); 160 #endif 161 } 162 163 struct inet_cork { 164 unsigned int flags; 165 __be32 addr; 166 struct ip_options *opt; 167 unsigned int fragsize; 168 int length; /* Total length of all frames */ 169 struct dst_entry *dst; 170 u8 tx_flags; 171 __u8 ttl; 172 __s16 tos; 173 char priority; 174 __u16 gso_size; 175 u64 transmit_time; 176 u32 mark; 177 }; 178 179 struct inet_cork_full { 180 struct inet_cork base; 181 struct flowi fl; 182 }; 183 184 struct ip_mc_socklist; 185 struct ipv6_pinfo; 186 struct rtable; 187 188 /** struct inet_sock - representation of INET sockets 189 * 190 * @sk - ancestor class 191 * @pinet6 - pointer to IPv6 control block 192 * @inet_daddr - Foreign IPv4 addr 193 * @inet_rcv_saddr - Bound local IPv4 addr 194 * @inet_dport - Destination port 195 * @inet_num - Local port 196 * @inet_saddr - Sending source 197 * @uc_ttl - Unicast TTL 198 * @inet_sport - Source port 199 * @inet_id - ID counter for DF pkts 200 * @tos - TOS 201 * @mc_ttl - Multicasting TTL 202 * @is_icsk - is this an inet_connection_sock? 203 * @uc_index - Unicast outgoing device index 204 * @mc_index - Multicast device index 205 * @mc_list - Group array 206 * @cork - info to build ip hdr on each ip frag while socket is corked 207 */ 208 struct inet_sock { 209 /* sk and pinet6 has to be the first two members of inet_sock */ 210 struct sock sk; 211 #if IS_ENABLED(CONFIG_IPV6) 212 struct ipv6_pinfo *pinet6; 213 #endif 214 /* Socket demultiplex comparisons on incoming packets. */ 215 #define inet_daddr sk.__sk_common.skc_daddr 216 #define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr 217 #define inet_dport sk.__sk_common.skc_dport 218 #define inet_num sk.__sk_common.skc_num 219 220 __be32 inet_saddr; 221 __s16 uc_ttl; 222 __u16 cmsg_flags; 223 struct ip_options_rcu __rcu *inet_opt; 224 __be16 inet_sport; 225 __u16 inet_id; 226 227 __u8 tos; 228 __u8 min_ttl; 229 __u8 mc_ttl; 230 __u8 pmtudisc; 231 __u8 recverr:1, 232 is_icsk:1, 233 freebind:1, 234 hdrincl:1, 235 mc_loop:1, 236 transparent:1, 237 mc_all:1, 238 nodefrag:1; 239 __u8 bind_address_no_port:1, 240 recverr_rfc4884:1, 241 defer_connect:1; /* Indicates that fastopen_connect is set 242 * and cookie exists so we defer connect 243 * until first data frame is written 244 */ 245 __u8 rcv_tos; 246 __u8 convert_csum; 247 int uc_index; 248 int mc_index; 249 __be32 mc_addr; 250 struct ip_mc_socklist __rcu *mc_list; 251 struct inet_cork_full cork; 252 }; 253 254 #define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */ 255 #define IPCORK_ALLFRAG 2 /* always fragment (for ipv6 for now) */ 256 257 /* cmsg flags for inet */ 258 #define IP_CMSG_PKTINFO BIT(0) 259 #define IP_CMSG_TTL BIT(1) 260 #define IP_CMSG_TOS BIT(2) 261 #define IP_CMSG_RECVOPTS BIT(3) 262 #define IP_CMSG_RETOPTS BIT(4) 263 #define IP_CMSG_PASSSEC BIT(5) 264 #define IP_CMSG_ORIGDSTADDR BIT(6) 265 #define IP_CMSG_CHECKSUM BIT(7) 266 #define IP_CMSG_RECVFRAGSIZE BIT(8) 267 268 static inline bool sk_is_inet(struct sock *sk) 269 { 270 return sk->sk_family == AF_INET || sk->sk_family == AF_INET6; 271 } 272 273 /** 274 * sk_to_full_sk - Access to a full socket 275 * @sk: pointer to a socket 276 * 277 * SYNACK messages might be attached to request sockets. 278 * Some places want to reach the listener in this case. 279 */ 280 static inline struct sock *sk_to_full_sk(struct sock *sk) 281 { 282 #ifdef CONFIG_INET 283 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 284 sk = inet_reqsk(sk)->rsk_listener; 285 #endif 286 return sk; 287 } 288 289 /* sk_to_full_sk() variant with a const argument */ 290 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk) 291 { 292 #ifdef CONFIG_INET 293 if (sk && sk->sk_state == TCP_NEW_SYN_RECV) 294 sk = ((const struct request_sock *)sk)->rsk_listener; 295 #endif 296 return sk; 297 } 298 299 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb) 300 { 301 return sk_to_full_sk(skb->sk); 302 } 303 304 static inline struct inet_sock *inet_sk(const struct sock *sk) 305 { 306 return (struct inet_sock *)sk; 307 } 308 309 static inline void __inet_sk_copy_descendant(struct sock *sk_to, 310 const struct sock *sk_from, 311 const int ancestor_size) 312 { 313 memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1, 314 sk_from->sk_prot->obj_size - ancestor_size); 315 } 316 317 int inet_sk_rebuild_header(struct sock *sk); 318 319 /** 320 * inet_sk_state_load - read sk->sk_state for lockless contexts 321 * @sk: socket pointer 322 * 323 * Paired with inet_sk_state_store(). Used in places we don't hold socket lock: 324 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ... 325 */ 326 static inline int inet_sk_state_load(const struct sock *sk) 327 { 328 /* state change might impact lockless readers. */ 329 return smp_load_acquire(&sk->sk_state); 330 } 331 332 /** 333 * inet_sk_state_store - update sk->sk_state 334 * @sk: socket pointer 335 * @newstate: new state 336 * 337 * Paired with inet_sk_state_load(). Should be used in contexts where 338 * state change might impact lockless readers. 339 */ 340 void inet_sk_state_store(struct sock *sk, int newstate); 341 342 void inet_sk_set_state(struct sock *sk, int state); 343 344 static inline unsigned int __inet_ehashfn(const __be32 laddr, 345 const __u16 lport, 346 const __be32 faddr, 347 const __be16 fport, 348 u32 initval) 349 { 350 return jhash_3words((__force __u32) laddr, 351 (__force __u32) faddr, 352 ((__u32) lport) << 16 | (__force __u32)fport, 353 initval); 354 } 355 356 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops, 357 struct sock *sk_listener, 358 bool attach_listener); 359 360 static inline __u8 inet_sk_flowi_flags(const struct sock *sk) 361 { 362 __u8 flags = 0; 363 364 if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl) 365 flags |= FLOWI_FLAG_ANYSRC; 366 return flags; 367 } 368 369 static inline void inet_inc_convert_csum(struct sock *sk) 370 { 371 inet_sk(sk)->convert_csum++; 372 } 373 374 static inline void inet_dec_convert_csum(struct sock *sk) 375 { 376 if (inet_sk(sk)->convert_csum > 0) 377 inet_sk(sk)->convert_csum--; 378 } 379 380 static inline bool inet_get_convert_csum(struct sock *sk) 381 { 382 return !!inet_sk(sk)->convert_csum; 383 } 384 385 386 static inline bool inet_can_nonlocal_bind(struct net *net, 387 struct inet_sock *inet) 388 { 389 return READ_ONCE(net->ipv4.sysctl_ip_nonlocal_bind) || 390 inet->freebind || inet->transparent; 391 } 392 393 static inline bool inet_addr_valid_or_nonlocal(struct net *net, 394 struct inet_sock *inet, 395 __be32 addr, 396 int addr_type) 397 { 398 return inet_can_nonlocal_bind(net, inet) || 399 addr == htonl(INADDR_ANY) || 400 addr_type == RTN_LOCAL || 401 addr_type == RTN_MULTICAST || 402 addr_type == RTN_BROADCAST; 403 } 404 405 #endif /* _INET_SOCK_H */ 406