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 sock *sk, struct sk_buff *skb, struct flowi *fl); 40 void (*send_check)(struct sock *sk, struct sk_buff *skb); 41 int (*rebuild_header)(struct sock *sk); 42 void (*sk_rx_dst_set)(struct sock *sk, const struct sk_buff *skb); 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 u16 net_header_len; 48 u16 net_frag_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, bool relax); 65 void (*mtu_reduced)(struct sock *sk); 66 }; 67 68 /** inet_connection_sock - INET connection oriented sock 69 * 70 * @icsk_accept_queue: FIFO of established children 71 * @icsk_bind_hash: Bind node 72 * @icsk_timeout: Timeout 73 * @icsk_retransmit_timer: Resend (no ack) 74 * @icsk_rto: Retransmit timeout 75 * @icsk_pmtu_cookie Last pmtu seen by socket 76 * @icsk_ca_ops Pluggable congestion control hook 77 * @icsk_af_ops Operations which are AF_INET{4,6} specific 78 * @icsk_ca_state: Congestion control state 79 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 80 * @icsk_pending: Scheduled timer event 81 * @icsk_backoff: Backoff 82 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 83 * @icsk_probes_out: unanswered 0 window probes 84 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 85 * @icsk_ack: Delayed ACK control data 86 * @icsk_mtup; MTU probing control data 87 */ 88 struct inet_connection_sock { 89 /* inet_sock has to be the first member! */ 90 struct inet_sock icsk_inet; 91 struct request_sock_queue icsk_accept_queue; 92 struct inet_bind_bucket *icsk_bind_hash; 93 unsigned long icsk_timeout; 94 struct timer_list icsk_retransmit_timer; 95 struct timer_list icsk_delack_timer; 96 __u32 icsk_rto; 97 __u32 icsk_pmtu_cookie; 98 const struct tcp_congestion_ops *icsk_ca_ops; 99 const struct inet_connection_sock_af_ops *icsk_af_ops; 100 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 101 __u8 icsk_ca_state:7, 102 icsk_ca_dst_locked:1; 103 __u8 icsk_retransmits; 104 __u8 icsk_pending; 105 __u8 icsk_backoff; 106 __u8 icsk_syn_retries; 107 __u8 icsk_probes_out; 108 __u16 icsk_ext_hdr_len; 109 struct { 110 __u8 pending; /* ACK is pending */ 111 __u8 quick; /* Scheduled number of quick acks */ 112 __u8 pingpong; /* The session is interactive */ 113 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 114 __u32 ato; /* Predicted tick of soft clock */ 115 unsigned long timeout; /* Currently scheduled timeout */ 116 __u32 lrcvtime; /* timestamp of last received data packet */ 117 __u16 last_seg_size; /* Size of last incoming segment */ 118 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 119 } icsk_ack; 120 struct { 121 int enabled; 122 123 /* Range of MTUs to search */ 124 int search_high; 125 int search_low; 126 127 /* Information on the current probe. */ 128 int probe_size; 129 130 u32 probe_timestamp; 131 } icsk_mtup; 132 u32 icsk_user_timeout; 133 134 u64 icsk_ca_priv[64 / sizeof(u64)]; 135 #define ICSK_CA_PRIV_SIZE (8 * sizeof(u64)) 136 }; 137 138 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 139 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 140 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 141 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */ 142 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */ 143 144 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 145 { 146 return (struct inet_connection_sock *)sk; 147 } 148 149 static inline void *inet_csk_ca(const struct sock *sk) 150 { 151 return (void *)inet_csk(sk)->icsk_ca_priv; 152 } 153 154 struct sock *inet_csk_clone_lock(const struct sock *sk, 155 const struct request_sock *req, 156 const gfp_t priority); 157 158 enum inet_csk_ack_state_t { 159 ICSK_ACK_SCHED = 1, 160 ICSK_ACK_TIMER = 2, 161 ICSK_ACK_PUSHED = 4, 162 ICSK_ACK_PUSHED2 = 8 163 }; 164 165 void inet_csk_init_xmit_timers(struct sock *sk, 166 void (*retransmit_handler)(unsigned long), 167 void (*delack_handler)(unsigned long), 168 void (*keepalive_handler)(unsigned long)); 169 void inet_csk_clear_xmit_timers(struct sock *sk); 170 171 static inline void inet_csk_schedule_ack(struct sock *sk) 172 { 173 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 174 } 175 176 static inline int inet_csk_ack_scheduled(const struct sock *sk) 177 { 178 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 179 } 180 181 static inline void inet_csk_delack_init(struct sock *sk) 182 { 183 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 184 } 185 186 void inet_csk_delete_keepalive_timer(struct sock *sk); 187 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 188 189 #ifdef INET_CSK_DEBUG 190 extern const char inet_csk_timer_bug_msg[]; 191 #endif 192 193 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 194 { 195 struct inet_connection_sock *icsk = inet_csk(sk); 196 197 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 198 icsk->icsk_pending = 0; 199 #ifdef INET_CSK_CLEAR_TIMERS 200 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 201 #endif 202 } else if (what == ICSK_TIME_DACK) { 203 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 204 #ifdef INET_CSK_CLEAR_TIMERS 205 sk_stop_timer(sk, &icsk->icsk_delack_timer); 206 #endif 207 } 208 #ifdef INET_CSK_DEBUG 209 else { 210 pr_debug("%s", inet_csk_timer_bug_msg); 211 } 212 #endif 213 } 214 215 /* 216 * Reset the retransmission timer 217 */ 218 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 219 unsigned long when, 220 const unsigned long max_when) 221 { 222 struct inet_connection_sock *icsk = inet_csk(sk); 223 224 if (when > max_when) { 225 #ifdef INET_CSK_DEBUG 226 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 227 sk, what, when, current_text_addr()); 228 #endif 229 when = max_when; 230 } 231 232 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 || 233 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE) { 234 icsk->icsk_pending = what; 235 icsk->icsk_timeout = jiffies + when; 236 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 237 } else if (what == ICSK_TIME_DACK) { 238 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 239 icsk->icsk_ack.timeout = jiffies + when; 240 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 241 } 242 #ifdef INET_CSK_DEBUG 243 else { 244 pr_debug("%s", inet_csk_timer_bug_msg); 245 } 246 #endif 247 } 248 249 static inline unsigned long 250 inet_csk_rto_backoff(const struct inet_connection_sock *icsk, 251 unsigned long max_when) 252 { 253 u64 when = (u64)icsk->icsk_rto << icsk->icsk_backoff; 254 255 return (unsigned long)min_t(u64, when, max_when); 256 } 257 258 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err); 259 260 struct request_sock *inet_csk_search_req(struct sock *sk, 261 const __be16 rport, 262 const __be32 raddr, 263 const __be32 laddr); 264 int inet_csk_bind_conflict(const struct sock *sk, 265 const struct inet_bind_bucket *tb, bool relax); 266 int inet_csk_get_port(struct sock *sk, unsigned short snum); 267 268 struct dst_entry *inet_csk_route_req(struct sock *sk, struct flowi4 *fl4, 269 const struct request_sock *req); 270 struct dst_entry *inet_csk_route_child_sock(struct sock *sk, struct sock *newsk, 271 const struct request_sock *req); 272 273 static inline void inet_csk_reqsk_queue_add(struct sock *sk, 274 struct request_sock *req, 275 struct sock *child) 276 { 277 reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child); 278 } 279 280 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, 281 unsigned long timeout); 282 283 static inline void inet_csk_reqsk_queue_added(struct sock *sk, 284 const unsigned long timeout) 285 { 286 reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue); 287 } 288 289 static inline int inet_csk_reqsk_queue_len(const struct sock *sk) 290 { 291 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue); 292 } 293 294 static inline int inet_csk_reqsk_queue_young(const struct sock *sk) 295 { 296 return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue); 297 } 298 299 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk) 300 { 301 return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue); 302 } 303 304 void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req); 305 306 void inet_csk_destroy_sock(struct sock *sk); 307 void inet_csk_prepare_forced_close(struct sock *sk); 308 309 /* 310 * LISTEN is a special case for poll.. 311 */ 312 static inline unsigned int inet_csk_listen_poll(const struct sock *sk) 313 { 314 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? 315 (POLLIN | POLLRDNORM) : 0; 316 } 317 318 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries); 319 void inet_csk_listen_stop(struct sock *sk); 320 321 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr); 322 323 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 324 char __user *optval, int __user *optlen); 325 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 326 char __user *optval, unsigned int optlen); 327 328 struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu); 329 #endif /* _INET_CONNECTION_SOCK_H */ 330