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 22 #include <net/inet_sock.h> 23 #include <net/request_sock.h> 24 25 #define INET_CSK_DEBUG 1 26 27 /* Cancel timers, when they are not required. */ 28 #undef INET_CSK_CLEAR_TIMERS 29 30 struct inet_bind_bucket; 31 struct inet_hashinfo; 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 int (*setsockopt)(struct sock *sk, int level, int optname, 50 char __user *optval, int optlen); 51 int (*getsockopt)(struct sock *sk, int level, int optname, 52 char __user *optval, int __user *optlen); 53 int (*compat_setsockopt)(struct sock *sk, 54 int level, int optname, 55 char __user *optval, int optlen); 56 int (*compat_getsockopt)(struct sock *sk, 57 int level, int optname, 58 char __user *optval, int __user *optlen); 59 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); 60 int sockaddr_len; 61 }; 62 63 /** inet_connection_sock - INET connection oriented sock 64 * 65 * @icsk_accept_queue: FIFO of established children 66 * @icsk_bind_hash: Bind node 67 * @icsk_timeout: Timeout 68 * @icsk_retransmit_timer: Resend (no ack) 69 * @icsk_rto: Retransmit timeout 70 * @icsk_pmtu_cookie Last pmtu seen by socket 71 * @icsk_ca_ops Pluggable congestion control hook 72 * @icsk_af_ops Operations which are AF_INET{4,6} specific 73 * @icsk_ca_state: Congestion control state 74 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 75 * @icsk_pending: Scheduled timer event 76 * @icsk_backoff: Backoff 77 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 78 * @icsk_probes_out: unanswered 0 window probes 79 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 80 * @icsk_ack: Delayed ACK control data 81 * @icsk_mtup; MTU probing control data 82 */ 83 struct inet_connection_sock { 84 /* inet_sock has to be the first member! */ 85 struct inet_sock icsk_inet; 86 struct request_sock_queue icsk_accept_queue; 87 struct inet_bind_bucket *icsk_bind_hash; 88 unsigned long icsk_timeout; 89 struct timer_list icsk_retransmit_timer; 90 struct timer_list icsk_delack_timer; 91 __u32 icsk_rto; 92 __u32 icsk_pmtu_cookie; 93 const struct tcp_congestion_ops *icsk_ca_ops; 94 const struct inet_connection_sock_af_ops *icsk_af_ops; 95 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 96 __u8 icsk_ca_state; 97 __u8 icsk_retransmits; 98 __u8 icsk_pending; 99 __u8 icsk_backoff; 100 __u8 icsk_syn_retries; 101 __u8 icsk_probes_out; 102 __u16 icsk_ext_hdr_len; 103 struct { 104 __u8 pending; /* ACK is pending */ 105 __u8 quick; /* Scheduled number of quick acks */ 106 __u8 pingpong; /* The session is interactive */ 107 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 108 __u32 ato; /* Predicted tick of soft clock */ 109 unsigned long timeout; /* Currently scheduled timeout */ 110 __u32 lrcvtime; /* timestamp of last received data packet */ 111 __u16 last_seg_size; /* Size of last incoming segment */ 112 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 113 } icsk_ack; 114 struct { 115 int enabled; 116 117 /* Range of MTUs to search */ 118 int search_high; 119 int search_low; 120 121 /* Information on the current probe. */ 122 int probe_size; 123 } icsk_mtup; 124 u32 icsk_ca_priv[16]; 125 #define ICSK_CA_PRIV_SIZE (16 * sizeof(u32)) 126 }; 127 128 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 129 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 130 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 131 #define ICSK_TIME_KEEPOPEN 4 /* Keepalive timer */ 132 133 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 134 { 135 return (struct inet_connection_sock *)sk; 136 } 137 138 static inline void *inet_csk_ca(const struct sock *sk) 139 { 140 return (void *)inet_csk(sk)->icsk_ca_priv; 141 } 142 143 extern struct sock *inet_csk_clone(struct sock *sk, 144 const struct request_sock *req, 145 const gfp_t priority); 146 147 enum inet_csk_ack_state_t { 148 ICSK_ACK_SCHED = 1, 149 ICSK_ACK_TIMER = 2, 150 ICSK_ACK_PUSHED = 4 151 }; 152 153 extern void inet_csk_init_xmit_timers(struct sock *sk, 154 void (*retransmit_handler)(unsigned long), 155 void (*delack_handler)(unsigned long), 156 void (*keepalive_handler)(unsigned long)); 157 extern void inet_csk_clear_xmit_timers(struct sock *sk); 158 159 static inline void inet_csk_schedule_ack(struct sock *sk) 160 { 161 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 162 } 163 164 static inline int inet_csk_ack_scheduled(const struct sock *sk) 165 { 166 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 167 } 168 169 static inline void inet_csk_delack_init(struct sock *sk) 170 { 171 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 172 } 173 174 extern void inet_csk_delete_keepalive_timer(struct sock *sk); 175 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 176 177 #ifdef INET_CSK_DEBUG 178 extern const char inet_csk_timer_bug_msg[]; 179 #endif 180 181 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 182 { 183 struct inet_connection_sock *icsk = inet_csk(sk); 184 185 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 186 icsk->icsk_pending = 0; 187 #ifdef INET_CSK_CLEAR_TIMERS 188 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 189 #endif 190 } else if (what == ICSK_TIME_DACK) { 191 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 192 #ifdef INET_CSK_CLEAR_TIMERS 193 sk_stop_timer(sk, &icsk->icsk_delack_timer); 194 #endif 195 } 196 #ifdef INET_CSK_DEBUG 197 else { 198 pr_debug("%s", inet_csk_timer_bug_msg); 199 } 200 #endif 201 } 202 203 /* 204 * Reset the retransmission timer 205 */ 206 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 207 unsigned long when, 208 const unsigned long max_when) 209 { 210 struct inet_connection_sock *icsk = inet_csk(sk); 211 212 if (when > max_when) { 213 #ifdef INET_CSK_DEBUG 214 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 215 sk, what, when, current_text_addr()); 216 #endif 217 when = max_when; 218 } 219 220 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 221 icsk->icsk_pending = what; 222 icsk->icsk_timeout = jiffies + when; 223 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 224 } else if (what == ICSK_TIME_DACK) { 225 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 226 icsk->icsk_ack.timeout = jiffies + when; 227 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 228 } 229 #ifdef INET_CSK_DEBUG 230 else { 231 pr_debug("%s", inet_csk_timer_bug_msg); 232 } 233 #endif 234 } 235 236 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err); 237 238 extern struct request_sock *inet_csk_search_req(const struct sock *sk, 239 struct request_sock ***prevp, 240 const __u16 rport, 241 const __u32 raddr, 242 const __u32 laddr); 243 extern int inet_csk_bind_conflict(const struct sock *sk, 244 const struct inet_bind_bucket *tb); 245 extern int inet_csk_get_port(struct inet_hashinfo *hashinfo, 246 struct sock *sk, unsigned short snum, 247 int (*bind_conflict)(const struct sock *sk, 248 const struct inet_bind_bucket *tb)); 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_ctl_sock_create(struct socket **sock, 331 unsigned short family, 332 unsigned short type, 333 unsigned char protocol); 334 335 extern int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 336 char __user *optval, int __user *optlen); 337 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 338 char __user *optval, int optlen); 339 #endif /* _INET_CONNECTION_SOCK_H */ 340