1 /* 2 * NET Generic infrastructure for INET connection oriented protocols. 3 * 4 * Definitions for inet_connection_sock 5 * 6 * Authors: Many people, see the TCP sources 7 * 8 * From code originally in TCP 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 */ 15 #ifndef _INET_CONNECTION_SOCK_H 16 #define _INET_CONNECTION_SOCK_H 17 18 #include <linux/compiler.h> 19 #include <linux/string.h> 20 #include <linux/timer.h> 21 #include <linux/poll.h> 22 23 #include <net/inet_sock.h> 24 #include <net/request_sock.h> 25 26 #define INET_CSK_DEBUG 1 27 28 /* Cancel timers, when they are not required. */ 29 #undef INET_CSK_CLEAR_TIMERS 30 31 struct inet_bind_bucket; 32 struct tcp_congestion_ops; 33 34 /* 35 * Pointers to address related TCP functions 36 * (i.e. things that depend on the address family) 37 */ 38 struct inet_connection_sock_af_ops { 39 int (*queue_xmit)(struct sk_buff *skb); 40 void (*send_check)(struct sock *sk, struct sk_buff *skb); 41 int (*rebuild_header)(struct sock *sk); 42 int (*conn_request)(struct sock *sk, struct sk_buff *skb); 43 struct sock *(*syn_recv_sock)(struct sock *sk, struct sk_buff *skb, 44 struct request_sock *req, 45 struct dst_entry *dst); 46 struct inet_peer *(*get_peer)(struct sock *sk, bool *release_it); 47 u16 net_header_len; 48 u16 sockaddr_len; 49 int (*setsockopt)(struct sock *sk, int level, int optname, 50 char __user *optval, unsigned int optlen); 51 int (*getsockopt)(struct sock *sk, int level, int optname, 52 char __user *optval, int __user *optlen); 53 #ifdef CONFIG_COMPAT 54 int (*compat_setsockopt)(struct sock *sk, 55 int level, int optname, 56 char __user *optval, unsigned int optlen); 57 int (*compat_getsockopt)(struct sock *sk, 58 int level, int optname, 59 char __user *optval, int __user *optlen); 60 #endif 61 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); 62 int (*bind_conflict)(const struct sock *sk, 63 const struct inet_bind_bucket *tb); 64 }; 65 66 /** inet_connection_sock - INET connection oriented sock 67 * 68 * @icsk_accept_queue: FIFO of established children 69 * @icsk_bind_hash: Bind node 70 * @icsk_timeout: Timeout 71 * @icsk_retransmit_timer: Resend (no ack) 72 * @icsk_rto: Retransmit timeout 73 * @icsk_pmtu_cookie Last pmtu seen by socket 74 * @icsk_ca_ops Pluggable congestion control hook 75 * @icsk_af_ops Operations which are AF_INET{4,6} specific 76 * @icsk_ca_state: Congestion control state 77 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 78 * @icsk_pending: Scheduled timer event 79 * @icsk_backoff: Backoff 80 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 81 * @icsk_probes_out: unanswered 0 window probes 82 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 83 * @icsk_ack: Delayed ACK control data 84 * @icsk_mtup; MTU probing control data 85 */ 86 struct inet_connection_sock { 87 /* inet_sock has to be the first member! */ 88 struct inet_sock icsk_inet; 89 struct request_sock_queue icsk_accept_queue; 90 struct inet_bind_bucket *icsk_bind_hash; 91 unsigned long icsk_timeout; 92 struct timer_list icsk_retransmit_timer; 93 struct timer_list icsk_delack_timer; 94 __u32 icsk_rto; 95 __u32 icsk_pmtu_cookie; 96 const struct tcp_congestion_ops *icsk_ca_ops; 97 const struct inet_connection_sock_af_ops *icsk_af_ops; 98 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 99 __u8 icsk_ca_state; 100 __u8 icsk_retransmits; 101 __u8 icsk_pending; 102 __u8 icsk_backoff; 103 __u8 icsk_syn_retries; 104 __u8 icsk_probes_out; 105 __u16 icsk_ext_hdr_len; 106 struct { 107 __u8 pending; /* ACK is pending */ 108 __u8 quick; /* Scheduled number of quick acks */ 109 __u8 pingpong; /* The session is interactive */ 110 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 111 __u32 ato; /* Predicted tick of soft clock */ 112 unsigned long timeout; /* Currently scheduled timeout */ 113 __u32 lrcvtime; /* timestamp of last received data packet */ 114 __u16 last_seg_size; /* Size of last incoming segment */ 115 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 116 } icsk_ack; 117 struct { 118 int enabled; 119 120 /* Range of MTUs to search */ 121 int search_high; 122 int search_low; 123 124 /* Information on the current probe. */ 125 int probe_size; 126 } icsk_mtup; 127 u32 icsk_ca_priv[16]; 128 u32 icsk_user_timeout; 129 #define ICSK_CA_PRIV_SIZE (16 * sizeof(u32)) 130 }; 131 132 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 133 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 134 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 135 136 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 137 { 138 return (struct inet_connection_sock *)sk; 139 } 140 141 static inline void *inet_csk_ca(const struct sock *sk) 142 { 143 return (void *)inet_csk(sk)->icsk_ca_priv; 144 } 145 146 extern struct sock *inet_csk_clone(struct sock *sk, 147 const struct request_sock *req, 148 const gfp_t priority); 149 150 enum inet_csk_ack_state_t { 151 ICSK_ACK_SCHED = 1, 152 ICSK_ACK_TIMER = 2, 153 ICSK_ACK_PUSHED = 4, 154 ICSK_ACK_PUSHED2 = 8 155 }; 156 157 extern void inet_csk_init_xmit_timers(struct sock *sk, 158 void (*retransmit_handler)(unsigned long), 159 void (*delack_handler)(unsigned long), 160 void (*keepalive_handler)(unsigned long)); 161 extern void inet_csk_clear_xmit_timers(struct sock *sk); 162 163 static inline void inet_csk_schedule_ack(struct sock *sk) 164 { 165 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 166 } 167 168 static inline int inet_csk_ack_scheduled(const struct sock *sk) 169 { 170 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 171 } 172 173 static inline void inet_csk_delack_init(struct sock *sk) 174 { 175 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 176 } 177 178 extern void inet_csk_delete_keepalive_timer(struct sock *sk); 179 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 180 181 #ifdef INET_CSK_DEBUG 182 extern const char inet_csk_timer_bug_msg[]; 183 #endif 184 185 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 186 { 187 struct inet_connection_sock *icsk = inet_csk(sk); 188 189 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 190 icsk->icsk_pending = 0; 191 #ifdef INET_CSK_CLEAR_TIMERS 192 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 193 #endif 194 } else if (what == ICSK_TIME_DACK) { 195 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 196 #ifdef INET_CSK_CLEAR_TIMERS 197 sk_stop_timer(sk, &icsk->icsk_delack_timer); 198 #endif 199 } 200 #ifdef INET_CSK_DEBUG 201 else { 202 pr_debug("%s", inet_csk_timer_bug_msg); 203 } 204 #endif 205 } 206 207 /* 208 * Reset the retransmission timer 209 */ 210 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 211 unsigned long when, 212 const unsigned long max_when) 213 { 214 struct inet_connection_sock *icsk = inet_csk(sk); 215 216 if (when > max_when) { 217 #ifdef INET_CSK_DEBUG 218 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 219 sk, what, when, current_text_addr()); 220 #endif 221 when = max_when; 222 } 223 224 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 225 icsk->icsk_pending = what; 226 icsk->icsk_timeout = jiffies + when; 227 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 228 } else if (what == ICSK_TIME_DACK) { 229 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 230 icsk->icsk_ack.timeout = jiffies + when; 231 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 232 } 233 #ifdef INET_CSK_DEBUG 234 else { 235 pr_debug("%s", inet_csk_timer_bug_msg); 236 } 237 #endif 238 } 239 240 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err); 241 242 extern struct request_sock *inet_csk_search_req(const struct sock *sk, 243 struct request_sock ***prevp, 244 const __be16 rport, 245 const __be32 raddr, 246 const __be32 laddr); 247 extern int inet_csk_bind_conflict(const struct sock *sk, 248 const struct inet_bind_bucket *tb); 249 extern int inet_csk_get_port(struct sock *sk, unsigned short snum); 250 251 extern struct dst_entry* inet_csk_route_req(struct sock *sk, 252 const struct request_sock *req); 253 254 static inline void inet_csk_reqsk_queue_add(struct sock *sk, 255 struct request_sock *req, 256 struct sock *child) 257 { 258 reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child); 259 } 260 261 extern void inet_csk_reqsk_queue_hash_add(struct sock *sk, 262 struct request_sock *req, 263 unsigned long timeout); 264 265 static inline void inet_csk_reqsk_queue_removed(struct sock *sk, 266 struct request_sock *req) 267 { 268 if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0) 269 inet_csk_delete_keepalive_timer(sk); 270 } 271 272 static inline void inet_csk_reqsk_queue_added(struct sock *sk, 273 const unsigned long timeout) 274 { 275 if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0) 276 inet_csk_reset_keepalive_timer(sk, timeout); 277 } 278 279 static inline int inet_csk_reqsk_queue_len(const struct sock *sk) 280 { 281 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue); 282 } 283 284 static inline int inet_csk_reqsk_queue_young(const struct sock *sk) 285 { 286 return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue); 287 } 288 289 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk) 290 { 291 return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue); 292 } 293 294 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk, 295 struct request_sock *req, 296 struct request_sock **prev) 297 { 298 reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev); 299 } 300 301 static inline void inet_csk_reqsk_queue_drop(struct sock *sk, 302 struct request_sock *req, 303 struct request_sock **prev) 304 { 305 inet_csk_reqsk_queue_unlink(sk, req, prev); 306 inet_csk_reqsk_queue_removed(sk, req); 307 reqsk_free(req); 308 } 309 310 extern void inet_csk_reqsk_queue_prune(struct sock *parent, 311 const unsigned long interval, 312 const unsigned long timeout, 313 const unsigned long max_rto); 314 315 extern void inet_csk_destroy_sock(struct sock *sk); 316 317 /* 318 * LISTEN is a special case for poll.. 319 */ 320 static inline unsigned int inet_csk_listen_poll(const struct sock *sk) 321 { 322 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? 323 (POLLIN | POLLRDNORM) : 0; 324 } 325 326 extern int inet_csk_listen_start(struct sock *sk, const int nr_table_entries); 327 extern void inet_csk_listen_stop(struct sock *sk); 328 329 extern void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr); 330 331 extern int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 332 char __user *optval, int __user *optlen); 333 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 334 char __user *optval, unsigned int optlen); 335 #endif /* _INET_CONNECTION_SOCK_H */ 336