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 inet_hashinfo; 33 struct tcp_congestion_ops; 34 35 /* 36 * Pointers to address related TCP functions 37 * (i.e. things that depend on the address family) 38 */ 39 struct inet_connection_sock_af_ops { 40 int (*queue_xmit)(struct sk_buff *skb, int ipfragok); 41 void (*send_check)(struct sock *sk, int len, 42 struct sk_buff *skb); 43 int (*rebuild_header)(struct sock *sk); 44 int (*conn_request)(struct sock *sk, struct sk_buff *skb); 45 struct sock *(*syn_recv_sock)(struct sock *sk, struct sk_buff *skb, 46 struct request_sock *req, 47 struct dst_entry *dst); 48 int (*remember_stamp)(struct sock *sk); 49 u16 net_header_len; 50 u16 sockaddr_len; 51 int (*setsockopt)(struct sock *sk, int level, int optname, 52 char __user *optval, int optlen); 53 int (*getsockopt)(struct sock *sk, int level, int optname, 54 char __user *optval, int __user *optlen); 55 int (*compat_setsockopt)(struct sock *sk, 56 int level, int optname, 57 char __user *optval, int optlen); 58 int (*compat_getsockopt)(struct sock *sk, 59 int level, int optname, 60 char __user *optval, int __user *optlen); 61 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); 62 }; 63 64 /** inet_connection_sock - INET connection oriented sock 65 * 66 * @icsk_accept_queue: FIFO of established children 67 * @icsk_bind_hash: Bind node 68 * @icsk_timeout: Timeout 69 * @icsk_retransmit_timer: Resend (no ack) 70 * @icsk_rto: Retransmit timeout 71 * @icsk_pmtu_cookie Last pmtu seen by socket 72 * @icsk_ca_ops Pluggable congestion control hook 73 * @icsk_af_ops Operations which are AF_INET{4,6} specific 74 * @icsk_ca_state: Congestion control state 75 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 76 * @icsk_pending: Scheduled timer event 77 * @icsk_backoff: Backoff 78 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 79 * @icsk_probes_out: unanswered 0 window probes 80 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 81 * @icsk_ack: Delayed ACK control data 82 * @icsk_mtup; MTU probing control data 83 */ 84 struct inet_connection_sock { 85 /* inet_sock has to be the first member! */ 86 struct inet_sock icsk_inet; 87 struct request_sock_queue icsk_accept_queue; 88 struct inet_bind_bucket *icsk_bind_hash; 89 unsigned long icsk_timeout; 90 struct timer_list icsk_retransmit_timer; 91 struct timer_list icsk_delack_timer; 92 __u32 icsk_rto; 93 __u32 icsk_pmtu_cookie; 94 const struct tcp_congestion_ops *icsk_ca_ops; 95 const struct inet_connection_sock_af_ops *icsk_af_ops; 96 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 97 __u8 icsk_ca_state; 98 __u8 icsk_retransmits; 99 __u8 icsk_pending; 100 __u8 icsk_backoff; 101 __u8 icsk_syn_retries; 102 __u8 icsk_probes_out; 103 __u16 icsk_ext_hdr_len; 104 struct { 105 __u8 pending; /* ACK is pending */ 106 __u8 quick; /* Scheduled number of quick acks */ 107 __u8 pingpong; /* The session is interactive */ 108 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 109 __u32 ato; /* Predicted tick of soft clock */ 110 unsigned long timeout; /* Currently scheduled timeout */ 111 __u32 lrcvtime; /* timestamp of last received data packet */ 112 __u16 last_seg_size; /* Size of last incoming segment */ 113 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 114 } icsk_ack; 115 struct { 116 int enabled; 117 118 /* Range of MTUs to search */ 119 int search_high; 120 int search_low; 121 122 /* Information on the current probe. */ 123 int probe_size; 124 } icsk_mtup; 125 u32 icsk_ca_priv[16]; 126 #define ICSK_CA_PRIV_SIZE (16 * sizeof(u32)) 127 }; 128 129 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 130 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 131 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 132 #define ICSK_TIME_KEEPOPEN 4 /* Keepalive timer */ 133 134 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 135 { 136 return (struct inet_connection_sock *)sk; 137 } 138 139 static inline void *inet_csk_ca(const struct sock *sk) 140 { 141 return (void *)inet_csk(sk)->icsk_ca_priv; 142 } 143 144 extern struct sock *inet_csk_clone(struct sock *sk, 145 const struct request_sock *req, 146 const gfp_t priority); 147 148 enum inet_csk_ack_state_t { 149 ICSK_ACK_SCHED = 1, 150 ICSK_ACK_TIMER = 2, 151 ICSK_ACK_PUSHED = 4, 152 ICSK_ACK_PUSHED2 = 8 153 }; 154 155 extern void inet_csk_init_xmit_timers(struct sock *sk, 156 void (*retransmit_handler)(unsigned long), 157 void (*delack_handler)(unsigned long), 158 void (*keepalive_handler)(unsigned long)); 159 extern void inet_csk_clear_xmit_timers(struct sock *sk); 160 161 static inline void inet_csk_schedule_ack(struct sock *sk) 162 { 163 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 164 } 165 166 static inline int inet_csk_ack_scheduled(const struct sock *sk) 167 { 168 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 169 } 170 171 static inline void inet_csk_delack_init(struct sock *sk) 172 { 173 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 174 } 175 176 extern void inet_csk_delete_keepalive_timer(struct sock *sk); 177 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 178 179 #ifdef INET_CSK_DEBUG 180 extern const char inet_csk_timer_bug_msg[]; 181 #endif 182 183 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 184 { 185 struct inet_connection_sock *icsk = inet_csk(sk); 186 187 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 188 icsk->icsk_pending = 0; 189 #ifdef INET_CSK_CLEAR_TIMERS 190 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 191 #endif 192 } else if (what == ICSK_TIME_DACK) { 193 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 194 #ifdef INET_CSK_CLEAR_TIMERS 195 sk_stop_timer(sk, &icsk->icsk_delack_timer); 196 #endif 197 } 198 #ifdef INET_CSK_DEBUG 199 else { 200 pr_debug("%s", inet_csk_timer_bug_msg); 201 } 202 #endif 203 } 204 205 /* 206 * Reset the retransmission timer 207 */ 208 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 209 unsigned long when, 210 const unsigned long max_when) 211 { 212 struct inet_connection_sock *icsk = inet_csk(sk); 213 214 if (when > max_when) { 215 #ifdef INET_CSK_DEBUG 216 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 217 sk, what, when, current_text_addr()); 218 #endif 219 when = max_when; 220 } 221 222 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 223 icsk->icsk_pending = what; 224 icsk->icsk_timeout = jiffies + when; 225 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 226 } else if (what == ICSK_TIME_DACK) { 227 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 228 icsk->icsk_ack.timeout = jiffies + when; 229 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 230 } 231 #ifdef INET_CSK_DEBUG 232 else { 233 pr_debug("%s", inet_csk_timer_bug_msg); 234 } 235 #endif 236 } 237 238 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err); 239 240 extern struct request_sock *inet_csk_search_req(const struct sock *sk, 241 struct request_sock ***prevp, 242 const __be16 rport, 243 const __be32 raddr, 244 const __be32 laddr); 245 extern int inet_csk_bind_conflict(const struct sock *sk, 246 const struct inet_bind_bucket *tb); 247 extern int inet_csk_get_port(struct inet_hashinfo *hashinfo, 248 struct sock *sk, unsigned short snum, 249 int (*bind_conflict)(const struct sock *sk, 250 const struct inet_bind_bucket *tb)); 251 252 extern struct dst_entry* inet_csk_route_req(struct sock *sk, 253 const struct request_sock *req); 254 255 static inline void inet_csk_reqsk_queue_add(struct sock *sk, 256 struct request_sock *req, 257 struct sock *child) 258 { 259 reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child); 260 } 261 262 extern void inet_csk_reqsk_queue_hash_add(struct sock *sk, 263 struct request_sock *req, 264 unsigned long timeout); 265 266 static inline void inet_csk_reqsk_queue_removed(struct sock *sk, 267 struct request_sock *req) 268 { 269 if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0) 270 inet_csk_delete_keepalive_timer(sk); 271 } 272 273 static inline void inet_csk_reqsk_queue_added(struct sock *sk, 274 const unsigned long timeout) 275 { 276 if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0) 277 inet_csk_reset_keepalive_timer(sk, timeout); 278 } 279 280 static inline int inet_csk_reqsk_queue_len(const struct sock *sk) 281 { 282 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue); 283 } 284 285 static inline int inet_csk_reqsk_queue_young(const struct sock *sk) 286 { 287 return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue); 288 } 289 290 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk) 291 { 292 return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue); 293 } 294 295 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk, 296 struct request_sock *req, 297 struct request_sock **prev) 298 { 299 reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev); 300 } 301 302 static inline void inet_csk_reqsk_queue_drop(struct sock *sk, 303 struct request_sock *req, 304 struct request_sock **prev) 305 { 306 inet_csk_reqsk_queue_unlink(sk, req, prev); 307 inet_csk_reqsk_queue_removed(sk, req); 308 reqsk_free(req); 309 } 310 311 extern void inet_csk_reqsk_queue_prune(struct sock *parent, 312 const unsigned long interval, 313 const unsigned long timeout, 314 const unsigned long max_rto); 315 316 extern void inet_csk_destroy_sock(struct sock *sk); 317 318 /* 319 * LISTEN is a special case for poll.. 320 */ 321 static inline unsigned int inet_csk_listen_poll(const struct sock *sk) 322 { 323 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? 324 (POLLIN | POLLRDNORM) : 0; 325 } 326 327 extern int inet_csk_listen_start(struct sock *sk, const int nr_table_entries); 328 extern void inet_csk_listen_stop(struct sock *sk); 329 330 extern void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr); 331 332 extern int inet_csk_ctl_sock_create(struct socket **sock, 333 unsigned short family, 334 unsigned short type, 335 unsigned char protocol); 336 337 extern int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 338 char __user *optval, int __user *optlen); 339 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 340 char __user *optval, int optlen); 341 #endif /* _INET_CONNECTION_SOCK_H */ 342