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_clean_acked Clean acked data hook 81 * @icsk_listen_portaddr_node hash to the portaddr listener hashtable 82 * @icsk_ca_state: Congestion control state 83 * @icsk_retransmits: Number of unrecovered [RTO] timeouts 84 * @icsk_pending: Scheduled timer event 85 * @icsk_backoff: Backoff 86 * @icsk_syn_retries: Number of allowed SYN (or equivalent) retries 87 * @icsk_probes_out: unanswered 0 window probes 88 * @icsk_ext_hdr_len: Network protocol overhead (IP/IPv6 options) 89 * @icsk_ack: Delayed ACK control data 90 * @icsk_mtup; MTU probing control data 91 */ 92 struct inet_connection_sock { 93 /* inet_sock has to be the first member! */ 94 struct inet_sock icsk_inet; 95 struct request_sock_queue icsk_accept_queue; 96 struct inet_bind_bucket *icsk_bind_hash; 97 unsigned long icsk_timeout; 98 struct timer_list icsk_retransmit_timer; 99 struct timer_list icsk_delack_timer; 100 __u32 icsk_rto; 101 __u32 icsk_pmtu_cookie; 102 const struct tcp_congestion_ops *icsk_ca_ops; 103 const struct inet_connection_sock_af_ops *icsk_af_ops; 104 const struct tcp_ulp_ops *icsk_ulp_ops; 105 void *icsk_ulp_data; 106 void (*icsk_clean_acked)(struct sock *sk, u32 acked_seq); 107 struct hlist_node icsk_listen_portaddr_node; 108 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 109 __u8 icsk_ca_state:6, 110 icsk_ca_setsockopt:1, 111 icsk_ca_dst_locked:1; 112 __u8 icsk_retransmits; 113 __u8 icsk_pending; 114 __u8 icsk_backoff; 115 __u8 icsk_syn_retries; 116 __u8 icsk_probes_out; 117 __u16 icsk_ext_hdr_len; 118 struct { 119 __u8 pending; /* ACK is pending */ 120 __u8 quick; /* Scheduled number of quick acks */ 121 __u8 pingpong; /* The session is interactive */ 122 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 123 __u32 ato; /* Predicted tick of soft clock */ 124 unsigned long timeout; /* Currently scheduled timeout */ 125 __u32 lrcvtime; /* timestamp of last received data packet */ 126 __u16 last_seg_size; /* Size of last incoming segment */ 127 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 128 } icsk_ack; 129 struct { 130 int enabled; 131 132 /* Range of MTUs to search */ 133 int search_high; 134 int search_low; 135 136 /* Information on the current probe. */ 137 int probe_size; 138 139 u32 probe_timestamp; 140 } icsk_mtup; 141 u32 icsk_user_timeout; 142 143 u64 icsk_ca_priv[88 / sizeof(u64)]; 144 #define ICSK_CA_PRIV_SIZE (11 * sizeof(u64)) 145 }; 146 147 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 148 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 149 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 150 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */ 151 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */ 152 #define ICSK_TIME_REO_TIMEOUT 6 /* Reordering timer */ 153 154 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 155 { 156 return (struct inet_connection_sock *)sk; 157 } 158 159 static inline void *inet_csk_ca(const struct sock *sk) 160 { 161 return (void *)inet_csk(sk)->icsk_ca_priv; 162 } 163 164 struct sock *inet_csk_clone_lock(const struct sock *sk, 165 const struct request_sock *req, 166 const gfp_t priority); 167 168 enum inet_csk_ack_state_t { 169 ICSK_ACK_SCHED = 1, 170 ICSK_ACK_TIMER = 2, 171 ICSK_ACK_PUSHED = 4, 172 ICSK_ACK_PUSHED2 = 8 173 }; 174 175 void inet_csk_init_xmit_timers(struct sock *sk, 176 void (*retransmit_handler)(struct timer_list *), 177 void (*delack_handler)(struct timer_list *), 178 void (*keepalive_handler)(struct timer_list *)); 179 void inet_csk_clear_xmit_timers(struct sock *sk); 180 181 static inline void inet_csk_schedule_ack(struct sock *sk) 182 { 183 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 184 } 185 186 static inline int inet_csk_ack_scheduled(const struct sock *sk) 187 { 188 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 189 } 190 191 static inline void inet_csk_delack_init(struct sock *sk) 192 { 193 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 194 } 195 196 void inet_csk_delete_keepalive_timer(struct sock *sk); 197 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 198 199 #ifdef INET_CSK_DEBUG 200 extern const char inet_csk_timer_bug_msg[]; 201 #endif 202 203 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 204 { 205 struct inet_connection_sock *icsk = inet_csk(sk); 206 207 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 208 icsk->icsk_pending = 0; 209 #ifdef INET_CSK_CLEAR_TIMERS 210 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 211 #endif 212 } else if (what == ICSK_TIME_DACK) { 213 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 214 #ifdef INET_CSK_CLEAR_TIMERS 215 sk_stop_timer(sk, &icsk->icsk_delack_timer); 216 #endif 217 } 218 #ifdef INET_CSK_DEBUG 219 else { 220 pr_debug("%s", inet_csk_timer_bug_msg); 221 } 222 #endif 223 } 224 225 /* 226 * Reset the retransmission timer 227 */ 228 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 229 unsigned long when, 230 const unsigned long max_when) 231 { 232 struct inet_connection_sock *icsk = inet_csk(sk); 233 234 if (when > max_when) { 235 #ifdef INET_CSK_DEBUG 236 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 237 sk, what, when, current_text_addr()); 238 #endif 239 when = max_when; 240 } 241 242 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 || 243 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE || 244 what == ICSK_TIME_REO_TIMEOUT) { 245 icsk->icsk_pending = what; 246 icsk->icsk_timeout = jiffies + when; 247 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout); 248 } else if (what == ICSK_TIME_DACK) { 249 icsk->icsk_ack.pending |= ICSK_ACK_TIMER; 250 icsk->icsk_ack.timeout = jiffies + when; 251 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout); 252 } 253 #ifdef INET_CSK_DEBUG 254 else { 255 pr_debug("%s", inet_csk_timer_bug_msg); 256 } 257 #endif 258 } 259 260 static inline unsigned long 261 inet_csk_rto_backoff(const struct inet_connection_sock *icsk, 262 unsigned long max_when) 263 { 264 u64 when = (u64)icsk->icsk_rto << icsk->icsk_backoff; 265 266 return (unsigned long)min_t(u64, when, max_when); 267 } 268 269 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err, bool kern); 270 271 int inet_csk_get_port(struct sock *sk, unsigned short snum); 272 273 struct dst_entry *inet_csk_route_req(const struct sock *sk, struct flowi4 *fl4, 274 const struct request_sock *req); 275 struct dst_entry *inet_csk_route_child_sock(const struct sock *sk, 276 struct sock *newsk, 277 const struct request_sock *req); 278 279 struct sock *inet_csk_reqsk_queue_add(struct sock *sk, 280 struct request_sock *req, 281 struct sock *child); 282 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, 283 unsigned long timeout); 284 struct sock *inet_csk_complete_hashdance(struct sock *sk, struct sock *child, 285 struct request_sock *req, 286 bool own_req); 287 288 static inline void inet_csk_reqsk_queue_added(struct sock *sk) 289 { 290 reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue); 291 } 292 293 static inline int inet_csk_reqsk_queue_len(const struct sock *sk) 294 { 295 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue); 296 } 297 298 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk) 299 { 300 return inet_csk_reqsk_queue_len(sk) >= sk->sk_max_ack_backlog; 301 } 302 303 void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req); 304 void inet_csk_reqsk_queue_drop_and_put(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 __poll_t inet_csk_listen_poll(const struct sock *sk) 313 { 314 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? 315 (EPOLLIN | EPOLLRDNORM) : 0; 316 } 317 318 int inet_csk_listen_start(struct sock *sk, int backlog); 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