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 /* Cancel timers, when they are not required. */ 27 #undef INET_CSK_CLEAR_TIMERS 28 29 struct inet_bind_bucket; 30 struct tcp_congestion_ops; 31 32 /* 33 * Pointers to address related TCP functions 34 * (i.e. things that depend on the address family) 35 */ 36 struct inet_connection_sock_af_ops { 37 int (*queue_xmit)(struct sock *sk, struct sk_buff *skb, struct flowi *fl); 38 void (*send_check)(struct sock *sk, struct sk_buff *skb); 39 int (*rebuild_header)(struct sock *sk); 40 void (*sk_rx_dst_set)(struct sock *sk, const struct sk_buff *skb); 41 int (*conn_request)(struct sock *sk, struct sk_buff *skb); 42 struct sock *(*syn_recv_sock)(const struct sock *sk, struct sk_buff *skb, 43 struct request_sock *req, 44 struct dst_entry *dst, 45 struct request_sock *req_unhash, 46 bool *own_req); 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 void (*mtu_reduced)(struct sock *sk); 64 }; 65 66 /** inet_connection_sock - INET connection oriented sock 67 * 68 * @icsk_accept_queue: FIFO of established children 69 * @icsk_bind_hash: Bind node 70 * @icsk_timeout: Timeout 71 * @icsk_retransmit_timer: Resend (no ack) 72 * @icsk_rto: Retransmit timeout 73 * @icsk_pmtu_cookie Last pmtu seen by socket 74 * @icsk_ca_ops Pluggable congestion control hook 75 * @icsk_af_ops Operations which are AF_INET{4,6} specific 76 * @icsk_ulp_ops Pluggable ULP control hook 77 * @icsk_ulp_data ULP private data 78 * @icsk_clean_acked Clean acked data hook 79 * @icsk_listen_portaddr_node hash to the portaddr listener hashtable 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 void (*icsk_clean_acked)(struct sock *sk, u32 acked_seq); 105 struct hlist_node icsk_listen_portaddr_node; 106 unsigned int (*icsk_sync_mss)(struct sock *sk, u32 pmtu); 107 __u8 icsk_ca_state:6, 108 icsk_ca_setsockopt:1, 109 icsk_ca_dst_locked:1; 110 __u8 icsk_retransmits; 111 __u8 icsk_pending; 112 __u8 icsk_backoff; 113 __u8 icsk_syn_retries; 114 __u8 icsk_probes_out; 115 __u16 icsk_ext_hdr_len; 116 struct { 117 __u8 pending; /* ACK is pending */ 118 __u8 quick; /* Scheduled number of quick acks */ 119 __u8 pingpong; /* The session is interactive */ 120 __u8 blocked; /* Delayed ACK was blocked by socket lock */ 121 __u32 ato; /* Predicted tick of soft clock */ 122 unsigned long timeout; /* Currently scheduled timeout */ 123 __u32 lrcvtime; /* timestamp of last received data packet */ 124 __u16 last_seg_size; /* Size of last incoming segment */ 125 __u16 rcv_mss; /* MSS used for delayed ACK decisions */ 126 } icsk_ack; 127 struct { 128 int enabled; 129 130 /* Range of MTUs to search */ 131 int search_high; 132 int search_low; 133 134 /* Information on the current probe. */ 135 int probe_size; 136 137 u32 probe_timestamp; 138 } icsk_mtup; 139 u32 icsk_user_timeout; 140 141 u64 icsk_ca_priv[88 / sizeof(u64)]; 142 #define ICSK_CA_PRIV_SIZE (11 * sizeof(u64)) 143 }; 144 145 #define ICSK_TIME_RETRANS 1 /* Retransmit timer */ 146 #define ICSK_TIME_DACK 2 /* Delayed ack timer */ 147 #define ICSK_TIME_PROBE0 3 /* Zero window probe timer */ 148 #define ICSK_TIME_EARLY_RETRANS 4 /* Early retransmit timer */ 149 #define ICSK_TIME_LOSS_PROBE 5 /* Tail loss probe timer */ 150 #define ICSK_TIME_REO_TIMEOUT 6 /* Reordering timer */ 151 152 static inline struct inet_connection_sock *inet_csk(const struct sock *sk) 153 { 154 return (struct inet_connection_sock *)sk; 155 } 156 157 static inline void *inet_csk_ca(const struct sock *sk) 158 { 159 return (void *)inet_csk(sk)->icsk_ca_priv; 160 } 161 162 struct sock *inet_csk_clone_lock(const struct sock *sk, 163 const struct request_sock *req, 164 const gfp_t priority); 165 166 enum inet_csk_ack_state_t { 167 ICSK_ACK_SCHED = 1, 168 ICSK_ACK_TIMER = 2, 169 ICSK_ACK_PUSHED = 4, 170 ICSK_ACK_PUSHED2 = 8 171 }; 172 173 void inet_csk_init_xmit_timers(struct sock *sk, 174 void (*retransmit_handler)(struct timer_list *), 175 void (*delack_handler)(struct timer_list *), 176 void (*keepalive_handler)(struct timer_list *)); 177 void inet_csk_clear_xmit_timers(struct sock *sk); 178 179 static inline void inet_csk_schedule_ack(struct sock *sk) 180 { 181 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED; 182 } 183 184 static inline int inet_csk_ack_scheduled(const struct sock *sk) 185 { 186 return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED; 187 } 188 189 static inline void inet_csk_delack_init(struct sock *sk) 190 { 191 memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack)); 192 } 193 194 void inet_csk_delete_keepalive_timer(struct sock *sk); 195 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout); 196 197 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what) 198 { 199 struct inet_connection_sock *icsk = inet_csk(sk); 200 201 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) { 202 icsk->icsk_pending = 0; 203 #ifdef INET_CSK_CLEAR_TIMERS 204 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 205 #endif 206 } else if (what == ICSK_TIME_DACK) { 207 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0; 208 #ifdef INET_CSK_CLEAR_TIMERS 209 sk_stop_timer(sk, &icsk->icsk_delack_timer); 210 #endif 211 } else { 212 pr_debug("inet_csk BUG: unknown timer value\n"); 213 } 214 } 215 216 /* 217 * Reset the retransmission timer 218 */ 219 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what, 220 unsigned long when, 221 const unsigned long max_when) 222 { 223 struct inet_connection_sock *icsk = inet_csk(sk); 224 225 if (when > max_when) { 226 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n", 227 sk, what, when, current_text_addr()); 228 when = max_when; 229 } 230 231 if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 || 232 what == ICSK_TIME_EARLY_RETRANS || what == ICSK_TIME_LOSS_PROBE || 233 what == ICSK_TIME_REO_TIMEOUT) { 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 } else { 242 pr_debug("inet_csk BUG: unknown timer value\n"); 243 } 244 } 245 246 static inline unsigned long 247 inet_csk_rto_backoff(const struct inet_connection_sock *icsk, 248 unsigned long max_when) 249 { 250 u64 when = (u64)icsk->icsk_rto << icsk->icsk_backoff; 251 252 return (unsigned long)min_t(u64, when, max_when); 253 } 254 255 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err, bool kern); 256 257 int inet_csk_get_port(struct sock *sk, unsigned short snum); 258 259 struct dst_entry *inet_csk_route_req(const struct sock *sk, struct flowi4 *fl4, 260 const struct request_sock *req); 261 struct dst_entry *inet_csk_route_child_sock(const struct sock *sk, 262 struct sock *newsk, 263 const struct request_sock *req); 264 265 struct sock *inet_csk_reqsk_queue_add(struct sock *sk, 266 struct request_sock *req, 267 struct sock *child); 268 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, 269 unsigned long timeout); 270 struct sock *inet_csk_complete_hashdance(struct sock *sk, struct sock *child, 271 struct request_sock *req, 272 bool own_req); 273 274 static inline void inet_csk_reqsk_queue_added(struct sock *sk) 275 { 276 reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue); 277 } 278 279 static inline int inet_csk_reqsk_queue_len(const struct sock *sk) 280 { 281 return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue); 282 } 283 284 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk) 285 { 286 return inet_csk_reqsk_queue_len(sk) >= sk->sk_max_ack_backlog; 287 } 288 289 void inet_csk_reqsk_queue_drop(struct sock *sk, struct request_sock *req); 290 void inet_csk_reqsk_queue_drop_and_put(struct sock *sk, struct request_sock *req); 291 292 void inet_csk_destroy_sock(struct sock *sk); 293 void inet_csk_prepare_forced_close(struct sock *sk); 294 295 /* 296 * LISTEN is a special case for poll.. 297 */ 298 static inline __poll_t inet_csk_listen_poll(const struct sock *sk) 299 { 300 return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ? 301 (EPOLLIN | EPOLLRDNORM) : 0; 302 } 303 304 int inet_csk_listen_start(struct sock *sk, int backlog); 305 void inet_csk_listen_stop(struct sock *sk); 306 307 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr); 308 309 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 310 char __user *optval, int __user *optlen); 311 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 312 char __user *optval, unsigned int optlen); 313 314 struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu); 315 #endif /* _INET_CONNECTION_SOCK_H */ 316