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, int ipfragok); 40 void (*send_check)(struct sock *sk, int len, 41 struct sk_buff *skb); 42 int (*rebuild_header)(struct sock *sk); 43 int (*conn_request)(struct sock *sk, struct sk_buff *skb); 44 struct sock *(*syn_recv_sock)(struct sock *sk, struct sk_buff *skb, 45 struct request_sock *req, 46 struct dst_entry *dst); 47 int (*remember_stamp)(struct sock *sk); 48 u16 net_header_len; 49 u16 sockaddr_len; 50 int (*setsockopt)(struct sock *sk, int level, int optname, 51 char __user *optval, unsigned int optlen); 52 int (*getsockopt)(struct sock *sk, int level, int optname, 53 char __user *optval, int __user *optlen); 54 #ifdef CONFIG_COMPAT 55 int (*compat_setsockopt)(struct sock *sk, 56 int level, int optname, 57 char __user *optval, unsigned int optlen); 58 int (*compat_getsockopt)(struct sock *sk, 59 int level, int optname, 60 char __user *optval, int __user *optlen); 61 #endif 62 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); 63 int (*bind_conflict)(const struct sock *sk, 64 const struct inet_bind_bucket *tb); 65 }; 66 67 /** inet_connection_sock - INET connection oriented sock 68 * 69 * @icsk_accept_queue: FIFO of established children 70 * @icsk_bind_hash: Bind node 71 * @icsk_timeout: Timeout 72 * @icsk_retransmit_timer: Resend (no ack) 73 * @icsk_rto: Retransmit timeout 74 * @icsk_pmtu_cookie Last pmtu seen by socket 75 * @icsk_ca_ops Pluggable congestion control hook 76 * @icsk_af_ops Operations which are AF_INET{4,6} specific 77 * @icsk_ca_state: Congestion control state 78 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 79 * @icsk_pending: Scheduled timer event 80 * @icsk_backoff: Backoff 81 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 82 * @icsk_probes_out: unanswered 0 window probes 83 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 84 * @icsk_ack: Delayed ACK control data 85 * @icsk_mtup; MTU probing control data 86 */ 87 struct inet_connection_sock { 88 /* inet_sock has to be the first member! */ 89 struct inet_sock icsk_inet; 90 struct request_sock_queue icsk_accept_queue; 91 struct inet_bind_bucket *icsk_bind_hash; 92 unsigned long icsk_timeout; 93 struct timer_list icsk_retransmit_timer; 94 struct timer_list icsk_delack_timer; 95 __u32 icsk_rto; 96 __u32 icsk_pmtu_cookie; 97 const struct tcp_congestion_ops *icsk_ca_ops; 98 const struct inet_connection_sock_af_ops *icsk_af_ops; 99 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 100 __u8 icsk_ca_state; 101 __u8 icsk_retransmits; 102 __u8 icsk_pending; 103 __u8 icsk_backoff; 104 __u8 icsk_syn_retries; 105 __u8 icsk_probes_out; 106 __u16 icsk_ext_hdr_len; 107 struct { 108 __u8 pending; /* ACK is pending */ 109 __u8 quick; /* Scheduled number of quick acks */ 110 __u8 pingpong; /* The session is interactive */ 111 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 112 __u32 ato; /* Predicted tick of soft clock */ 113 unsigned long timeout; /* Currently scheduled timeout */ 114 __u32 lrcvtime; /* timestamp of last received data packet */ 115 __u16 last_seg_size; /* Size of last incoming segment */ 116 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 117 } icsk_ack; 118 struct { 119 int enabled; 120 121 /* Range of MTUs to search */ 122 int search_high; 123 int search_low; 124 125 /* Information on the current probe. */ 126 int probe_size; 127 } icsk_mtup; 128 u32 icsk_ca_priv[16]; 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 #define ICSK_TIME_KEEPOPEN 4 /* Keepalive timer */ 136 137 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 138 { 139 return (struct inet_connection_sock *)sk; 140 } 141 142 static inline void *inet_csk_ca(const struct sock *sk) 143 { 144 return (void *)inet_csk(sk)->icsk_ca_priv; 145 } 146 147 extern struct sock *inet_csk_clone(struct sock *sk, 148 const struct request_sock *req, 149 const gfp_t priority); 150 151 enum inet_csk_ack_state_t { 152 ICSK_ACK_SCHED = 1, 153 ICSK_ACK_TIMER = 2, 154 ICSK_ACK_PUSHED = 4, 155 ICSK_ACK_PUSHED2 = 8 156 }; 157 158 extern void inet_csk_init_xmit_timers(struct sock *sk, 159 void (*retransmit_handler)(unsigned long), 160 void (*delack_handler)(unsigned long), 161 void (*keepalive_handler)(unsigned long)); 162 extern void inet_csk_clear_xmit_timers(struct sock *sk); 163 164 static inline void inet_csk_schedule_ack(struct sock *sk) 165 { 166 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 167 } 168 169 static inline int inet_csk_ack_scheduled(const struct sock *sk) 170 { 171 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 172 } 173 174 static inline void inet_csk_delack_init(struct sock *sk) 175 { 176 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 177 } 178 179 extern void inet_csk_delete_keepalive_timer(struct sock *sk); 180 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 181 182 #ifdef INET_CSK_DEBUG 183 extern const char inet_csk_timer_bug_msg[]; 184 #endif 185 186 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 187 { 188 struct inet_connection_sock *icsk = inet_csk(sk); 189 190 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 191 icsk->icsk_pending = 0; 192 #ifdef INET_CSK_CLEAR_TIMERS 193 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 194 #endif 195 } else if (what == ICSK_TIME_DACK) { 196 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 197 #ifdef INET_CSK_CLEAR_TIMERS 198 sk_stop_timer(sk, &icsk->icsk_delack_timer); 199 #endif 200 } 201 #ifdef INET_CSK_DEBUG 202 else { 203 pr_debug("%s", inet_csk_timer_bug_msg); 204 } 205 #endif 206 } 207 208 /* 209 * Reset the retransmission timer 210 */ 211 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 212 unsigned long when, 213 const unsigned long max_when) 214 { 215 struct inet_connection_sock *icsk = inet_csk(sk); 216 217 if (when > max_when) { 218 #ifdef INET_CSK_DEBUG 219 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 220 sk, what, when, current_text_addr()); 221 #endif 222 when = max_when; 223 } 224 225 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 226 icsk->icsk_pending = what; 227 icsk->icsk_timeout = jiffies + when; 228 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 229 } else if (what == ICSK_TIME_DACK) { 230 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 231 icsk->icsk_ack.timeout = jiffies + when; 232 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 233 } 234 #ifdef INET_CSK_DEBUG 235 else { 236 pr_debug("%s", inet_csk_timer_bug_msg); 237 } 238 #endif 239 } 240 241 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err); 242 243 extern struct request_sock *inet_csk_search_req(const struct sock *sk, 244 struct request_sock ***prevp, 245 const __be16 rport, 246 const __be32 raddr, 247 const __be32 laddr); 248 extern int inet_csk_bind_conflict(const struct sock *sk, 249 const struct inet_bind_bucket *tb); 250 extern int inet_csk_get_port(struct sock *sk, unsigned short snum); 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_compat_getsockopt(struct sock *sk, int level, int optname, 333 char __user *optval, int __user *optlen); 334 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 335 char __user *optval, unsigned int optlen); 336 #endif /* _INET_CONNECTION_SOCK_H */ 337