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