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)(const struct sock *sk, struct sk_buff *skb, 45 struct request_sock *req, 46 struct dst_entry *dst, 47 struct request_sock *req_unhash, 48 bool *own_req); 49 u16 net_header_len; 50 u16 net_frag_header_len; 51 u16 sockaddr_len; 52 int (*setsockopt)(struct sock *sk, int level, int optname, 53 char __user *optval, unsigned int optlen); 54 int (*getsockopt)(struct sock *sk, int level, int optname, 55 char __user *optval, int __user *optlen); 56 #ifdef CONFIG_COMPAT 57 int (*compat_setsockopt)(struct sock *sk, 58 int level, int optname, 59 char __user *optval, unsigned int optlen); 60 int (*compat_getsockopt)(struct sock *sk, 61 int level, int optname, 62 char __user *optval, int __user *optlen); 63 #endif 64 void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); 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_ulp_ops Pluggable ULP control hook 79 * @icsk_ulp_data ULP private data 80 * @icsk_ca_state: Congestion control state 81 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 82 * @icsk_pending: Scheduled timer event 83 * @icsk_backoff: Backoff 84 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 85 * @icsk_probes_out: unanswered 0 window probes 86 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 87 * @icsk_ack: Delayed ACK control data 88 * @icsk_mtup; MTU probing control data 89 */ 90 struct inet_connection_sock { 91 /* inet_sock has to be the first member! */ 92 struct inet_sock icsk_inet; 93 struct request_sock_queue icsk_accept_queue; 94 struct inet_bind_bucket *icsk_bind_hash; 95 unsigned long icsk_timeout; 96 struct timer_list icsk_retransmit_timer; 97 struct timer_list icsk_delack_timer; 98 __u32 icsk_rto; 99 __u32 icsk_pmtu_cookie; 100 const struct tcp_congestion_ops *icsk_ca_ops; 101 const struct inet_connection_sock_af_ops *icsk_af_ops; 102 const struct tcp_ulp_ops *icsk_ulp_ops; 103 void *icsk_ulp_data; 104 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 105 __u8 icsk_ca_state:6, 106 icsk_ca_setsockopt:1, 107 icsk_ca_dst_locked:1; 108 __u8 icsk_retransmits; 109 __u8 icsk_pending; 110 __u8 icsk_backoff; 111 __u8 icsk_syn_retries; 112 __u8 icsk_probes_out; 113 __u16 icsk_ext_hdr_len; 114 struct { 115 __u8 pending; /* ACK is pending */ 116 __u8 quick; /* Scheduled number of quick acks */ 117 __u8 pingpong; /* The session is interactive */ 118 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 119 __u32 ato; /* Predicted tick of soft clock */ 120 unsigned long timeout; /* Currently scheduled timeout */ 121 __u32 lrcvtime; /* timestamp of last received data packet */ 122 __u16 last_seg_size; /* Size of last incoming segment */ 123 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 124 } icsk_ack; 125 struct { 126 int enabled; 127 128 /* Range of MTUs to search */ 129 int search_high; 130 int search_low; 131 132 /* Information on the current probe. */ 133 int probe_size; 134 135 u32 probe_timestamp; 136 } icsk_mtup; 137 u32 icsk_user_timeout; 138 139 u64 icsk_ca_priv[88 / sizeof(u64)]; 140 #define ICSK_CA_PRIV_SIZE (11 * sizeof(u64)) 141 }; 142 143 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 144 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 145 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 146 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */ 147 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */ 148 #define ICSK_TIME_REO_TIMEOUT 6 /* Reordering timer */ 149 150 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 151 { 152 return (struct inet_connection_sock *)sk; 153 } 154 155 static inline void *inet_csk_ca(const struct sock *sk) 156 { 157 return (void *)inet_csk(sk)->icsk_ca_priv; 158 } 159 160 struct sock *inet_csk_clone_lock(const struct sock *sk, 161 const struct request_sock *req, 162 const gfp_t priority); 163 164 enum inet_csk_ack_state_t { 165 ICSK_ACK_SCHED = 1, 166 ICSK_ACK_TIMER = 2, 167 ICSK_ACK_PUSHED = 4, 168 ICSK_ACK_PUSHED2 = 8 169 }; 170 171 void inet_csk_init_xmit_timers(struct sock *sk, 172 void (*retransmit_handler)(unsigned long), 173 void (*delack_handler)(unsigned long), 174 void (*keepalive_handler)(unsigned long)); 175 void inet_csk_clear_xmit_timers(struct sock *sk); 176 177 static inline void inet_csk_schedule_ack(struct sock *sk) 178 { 179 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 180 } 181 182 static inline int inet_csk_ack_scheduled(const struct sock *sk) 183 { 184 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 185 } 186 187 static inline void inet_csk_delack_init(struct sock *sk) 188 { 189 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 190 } 191 192 void inet_csk_delete_keepalive_timer(struct sock *sk); 193 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 194 195 #ifdef INET_CSK_DEBUG 196 extern const char inet_csk_timer_bug_msg[]; 197 #endif 198 199 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 200 { 201 struct inet_connection_sock *icsk = inet_csk(sk); 202 203 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 204 icsk->icsk_pending = 0; 205 #ifdef INET_CSK_CLEAR_TIMERS 206 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 207 #endif 208 } else if (what == ICSK_TIME_DACK) { 209 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 210 #ifdef INET_CSK_CLEAR_TIMERS 211 sk_stop_timer(sk, &icsk->icsk_delack_timer); 212 #endif 213 } 214 #ifdef INET_CSK_DEBUG 215 else { 216 pr_debug("%s", inet_csk_timer_bug_msg); 217 } 218 #endif 219 } 220 221 /* 222 * Reset the retransmission timer 223 */ 224 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 225 unsigned long when, 226 const unsigned long max_when) 227 { 228 struct inet_connection_sock *icsk = inet_csk(sk); 229 230 if (when > max_when) { 231 #ifdef INET_CSK_DEBUG 232 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 233 sk, what, when, current_text_addr()); 234 #endif 235 when = max_when; 236 } 237 238 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 || 239 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE || 240 what == ICSK_TIME_REO_TIMEOUT) { 241 icsk->icsk_pending = what; 242 icsk->icsk_timeout = jiffies + when; 243 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 244 } else if (what == ICSK_TIME_DACK) { 245 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 246 icsk->icsk_ack.timeout = jiffies + when; 247 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 248 } 249 #ifdef INET_CSK_DEBUG 250 else { 251 pr_debug("%s", inet_csk_timer_bug_msg); 252 } 253 #endif 254 } 255 256 static inline unsigned long 257 inet_csk_rto_backoff(const struct inet_connection_sock *icsk, 258 unsigned long max_when) 259 { 260 u64 when = (u64)icsk->icsk_rto << icsk->icsk_backoff; 261 262 return (unsigned long)min_t(u64, when, max_when); 263 } 264 265 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err, bool kern); 266 267 int inet_csk_get_port(struct sock *sk, unsigned short snum); 268 269 struct dst_entry *inet_csk_route_req(const struct sock *sk, struct flowi4 *fl4, 270 const struct request_sock *req); 271 struct dst_entry *inet_csk_route_child_sock(const struct sock *sk, 272 struct sock *newsk, 273 const struct request_sock *req); 274 275 struct sock *inet_csk_reqsk_queue_add(struct sock *sk, 276 struct request_sock *req, 277 struct sock *child); 278 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, 279 unsigned long timeout); 280 struct sock *inet_csk_complete_hashdance(struct sock *sk, struct sock *child, 281 struct request_sock *req, 282 bool own_req); 283 284 static inline void inet_csk_reqsk_queue_added(struct sock *sk) 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_is_full(const struct sock *sk) 295 { 296 return inet_csk_reqsk_queue_len(sk) >= sk->sk_max_ack_backlog; 297 } 298 299 void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req); 300 void inet_csk_reqsk_queue_drop_and_put(struct sock *sk, struct request_sock *req); 301 302 void inet_csk_destroy_sock(struct sock *sk); 303 void inet_csk_prepare_forced_close(struct sock *sk); 304 305 /* 306 * LISTEN is a special case for poll.. 307 */ 308 static inline unsigned int inet_csk_listen_poll(const struct sock *sk) 309 { 310 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? 311 (POLLIN | POLLRDNORM) : 0; 312 } 313 314 int inet_csk_listen_start(struct sock *sk, int backlog); 315 void inet_csk_listen_stop(struct sock *sk); 316 317 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr); 318 319 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 320 char __user *optval, int __user *optlen); 321 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 322 char __user *optval, unsigned int optlen); 323 324 struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu); 325 #endif /* _INET_CONNECTION_SOCK_H */ 326