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2390 lines
72 KiB
2390 lines
72 KiB
/* SPDX-License-Identifier: GPL-2.0-or-later */ |
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/* |
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* INET An implementation of the TCP/IP protocol suite for the LINUX |
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* operating system. INET is implemented using the BSD Socket |
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* interface as the means of communication with the user level. |
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* |
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* Definitions for the TCP module. |
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* |
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* Version: @(#)tcp.h 1.0.5 05/23/93 |
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* |
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* Authors: Ross Biro |
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* Fred N. van Kempen, <[email protected]> |
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*/ |
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#ifndef _TCP_H |
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#define _TCP_H |
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#define FASTRETRANS_DEBUG 1 |
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#include <linux/list.h> |
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#include <linux/tcp.h> |
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#include <linux/bug.h> |
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#include <linux/slab.h> |
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#include <linux/cache.h> |
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#include <linux/percpu.h> |
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#include <linux/skbuff.h> |
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#include <linux/kref.h> |
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#include <linux/ktime.h> |
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#include <linux/indirect_call_wrapper.h> |
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#include <net/inet_connection_sock.h> |
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#include <net/inet_timewait_sock.h> |
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#include <net/inet_hashtables.h> |
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#include <net/checksum.h> |
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#include <net/request_sock.h> |
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#include <net/sock_reuseport.h> |
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#include <net/sock.h> |
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#include <net/snmp.h> |
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#include <net/ip.h> |
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#include <net/tcp_states.h> |
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#include <net/inet_ecn.h> |
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#include <net/dst.h> |
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#include <net/mptcp.h> |
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#include <linux/seq_file.h> |
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#include <linux/memcontrol.h> |
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#include <linux/bpf-cgroup.h> |
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#include <linux/siphash.h> |
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extern struct inet_hashinfo tcp_hashinfo; |
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extern struct percpu_counter tcp_orphan_count; |
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void tcp_time_wait(struct sock *sk, int state, int timeo); |
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#define MAX_TCP_HEADER L1_CACHE_ALIGN(128 + MAX_HEADER) |
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#define MAX_TCP_OPTION_SPACE 40 |
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#define TCP_MIN_SND_MSS 48 |
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#define TCP_MIN_GSO_SIZE (TCP_MIN_SND_MSS - MAX_TCP_OPTION_SPACE) |
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/* |
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* Never offer a window over 32767 without using window scaling. Some |
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* poor stacks do signed 16bit maths! |
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*/ |
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#define MAX_TCP_WINDOW 32767U |
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/* Minimal accepted MSS. It is (60+60+8) - (20+20). */ |
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#define TCP_MIN_MSS 88U |
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/* The initial MTU to use for probing */ |
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#define TCP_BASE_MSS 1024 |
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/* probing interval, default to 10 minutes as per RFC4821 */ |
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#define TCP_PROBE_INTERVAL 600 |
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/* Specify interval when tcp mtu probing will stop */ |
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#define TCP_PROBE_THRESHOLD 8 |
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/* After receiving this amount of duplicate ACKs fast retransmit starts. */ |
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#define TCP_FASTRETRANS_THRESH 3 |
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/* Maximal number of ACKs sent quickly to accelerate slow-start. */ |
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#define TCP_MAX_QUICKACKS 16U |
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/* Maximal number of window scale according to RFC1323 */ |
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#define TCP_MAX_WSCALE 14U |
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/* urg_data states */ |
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#define TCP_URG_VALID 0x0100 |
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#define TCP_URG_NOTYET 0x0200 |
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#define TCP_URG_READ 0x0400 |
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#define TCP_RETR1 3 /* |
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* This is how many retries it does before it |
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* tries to figure out if the gateway is |
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* down. Minimal RFC value is 3; it corresponds |
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* to ~3sec-8min depending on RTO. |
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*/ |
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#define TCP_RETR2 15 /* |
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* This should take at least |
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* 90 minutes to time out. |
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* RFC1122 says that the limit is 100 sec. |
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* 15 is ~13-30min depending on RTO. |
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*/ |
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#define TCP_SYN_RETRIES 6 /* This is how many retries are done |
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* when active opening a connection. |
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* RFC1122 says the minimum retry MUST |
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* be at least 180secs. Nevertheless |
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* this value is corresponding to |
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* 63secs of retransmission with the |
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* current initial RTO. |
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*/ |
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#define TCP_SYNACK_RETRIES 5 /* This is how may retries are done |
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* when passive opening a connection. |
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* This is corresponding to 31secs of |
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* retransmission with the current |
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* initial RTO. |
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*/ |
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#define TCP_TIMEWAIT_LEN (60*HZ) /* how long to wait to destroy TIME-WAIT |
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* state, about 60 seconds */ |
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#define TCP_FIN_TIMEOUT TCP_TIMEWAIT_LEN |
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/* BSD style FIN_WAIT2 deadlock breaker. |
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* It used to be 3min, new value is 60sec, |
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* to combine FIN-WAIT-2 timeout with |
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* TIME-WAIT timer. |
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*/ |
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#define TCP_FIN_TIMEOUT_MAX (120 * HZ) /* max TCP_LINGER2 value (two minutes) */ |
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#define TCP_DELACK_MAX ((unsigned)(HZ/5)) /* maximal time to delay before sending an ACK */ |
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#if HZ >= 100 |
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#define TCP_DELACK_MIN ((unsigned)(HZ/25)) /* minimal time to delay before sending an ACK */ |
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#define TCP_ATO_MIN ((unsigned)(HZ/25)) |
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#else |
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#define TCP_DELACK_MIN 4U |
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#define TCP_ATO_MIN 4U |
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#endif |
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#define TCP_RTO_MAX ((unsigned)(120*HZ)) |
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#define TCP_RTO_MIN ((unsigned)(HZ/5)) |
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#define TCP_TIMEOUT_MIN (2U) /* Min timeout for TCP timers in jiffies */ |
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#define TCP_TIMEOUT_INIT ((unsigned)(1*HZ)) /* RFC6298 2.1 initial RTO value */ |
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#define TCP_TIMEOUT_FALLBACK ((unsigned)(3*HZ)) /* RFC 1122 initial RTO value, now |
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* used as a fallback RTO for the |
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* initial data transmission if no |
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* valid RTT sample has been acquired, |
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* most likely due to retrans in 3WHS. |
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*/ |
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#define TCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ/2U)) /* Maximal interval between probes |
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* for local resources. |
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*/ |
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#define TCP_KEEPALIVE_TIME (120*60*HZ) /* two hours */ |
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#define TCP_KEEPALIVE_PROBES 9 /* Max of 9 keepalive probes */ |
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#define TCP_KEEPALIVE_INTVL (75*HZ) |
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#define MAX_TCP_KEEPIDLE 32767 |
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#define MAX_TCP_KEEPINTVL 32767 |
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#define MAX_TCP_KEEPCNT 127 |
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#define MAX_TCP_SYNCNT 127 |
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#define TCP_SYNQ_INTERVAL (HZ/5) /* Period of SYNACK timer */ |
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#define TCP_PAWS_24DAYS (60 * 60 * 24 * 24) |
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#define TCP_PAWS_MSL 60 /* Per-host timestamps are invalidated |
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* after this time. It should be equal |
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* (or greater than) TCP_TIMEWAIT_LEN |
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* to provide reliability equal to one |
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* provided by timewait state. |
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*/ |
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#define TCP_PAWS_WINDOW 1 /* Replay window for per-host |
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* timestamps. It must be less than |
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* minimal timewait lifetime. |
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*/ |
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/* |
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* TCP option |
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*/ |
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#define TCPOPT_NOP 1 /* Padding */ |
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#define TCPOPT_EOL 0 /* End of options */ |
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#define TCPOPT_MSS 2 /* Segment size negotiating */ |
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#define TCPOPT_WINDOW 3 /* Window scaling */ |
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#define TCPOPT_SACK_PERM 4 /* SACK Permitted */ |
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#define TCPOPT_SACK 5 /* SACK Block */ |
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#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */ |
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#define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */ |
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#define TCPOPT_MPTCP 30 /* Multipath TCP (RFC6824) */ |
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#define TCPOPT_FASTOPEN 34 /* Fast open (RFC7413) */ |
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#define TCPOPT_EXP 254 /* Experimental */ |
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/* Magic number to be after the option value for sharing TCP |
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* experimental options. See draft-ietf-tcpm-experimental-options-00.txt |
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*/ |
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#define TCPOPT_FASTOPEN_MAGIC 0xF989 |
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#define TCPOPT_SMC_MAGIC 0xE2D4C3D9 |
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/* |
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* TCP option lengths |
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*/ |
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#define TCPOLEN_MSS 4 |
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#define TCPOLEN_WINDOW 3 |
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#define TCPOLEN_SACK_PERM 2 |
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#define TCPOLEN_TIMESTAMP 10 |
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#define TCPOLEN_MD5SIG 18 |
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#define TCPOLEN_FASTOPEN_BASE 2 |
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#define TCPOLEN_EXP_FASTOPEN_BASE 4 |
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#define TCPOLEN_EXP_SMC_BASE 6 |
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/* But this is what stacks really send out. */ |
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#define TCPOLEN_TSTAMP_ALIGNED 12 |
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#define TCPOLEN_WSCALE_ALIGNED 4 |
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#define TCPOLEN_SACKPERM_ALIGNED 4 |
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#define TCPOLEN_SACK_BASE 2 |
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#define TCPOLEN_SACK_BASE_ALIGNED 4 |
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#define TCPOLEN_SACK_PERBLOCK 8 |
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#define TCPOLEN_MD5SIG_ALIGNED 20 |
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#define TCPOLEN_MSS_ALIGNED 4 |
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#define TCPOLEN_EXP_SMC_BASE_ALIGNED 8 |
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/* Flags in tp->nonagle */ |
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#define TCP_NAGLE_OFF 1 /* Nagle's algo is disabled */ |
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#define TCP_NAGLE_CORK 2 /* Socket is corked */ |
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#define TCP_NAGLE_PUSH 4 /* Cork is overridden for already queued data */ |
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/* TCP thin-stream limits */ |
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#define TCP_THIN_LINEAR_RETRIES 6 /* After 6 linear retries, do exp. backoff */ |
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/* TCP initial congestion window as per rfc6928 */ |
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#define TCP_INIT_CWND 10 |
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/* Bit Flags for sysctl_tcp_fastopen */ |
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#define TFO_CLIENT_ENABLE 1 |
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#define TFO_SERVER_ENABLE 2 |
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#define TFO_CLIENT_NO_COOKIE 4 /* Data in SYN w/o cookie option */ |
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/* Accept SYN data w/o any cookie option */ |
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#define TFO_SERVER_COOKIE_NOT_REQD 0x200 |
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/* Force enable TFO on all listeners, i.e., not requiring the |
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* TCP_FASTOPEN socket option. |
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*/ |
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#define TFO_SERVER_WO_SOCKOPT1 0x400 |
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/* sysctl variables for tcp */ |
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extern int sysctl_tcp_max_orphans; |
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extern long sysctl_tcp_mem[3]; |
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#define TCP_RACK_LOSS_DETECTION 0x1 /* Use RACK to detect losses */ |
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#define TCP_RACK_STATIC_REO_WND 0x2 /* Use static RACK reo wnd */ |
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#define TCP_RACK_NO_DUPTHRESH 0x4 /* Do not use DUPACK threshold in RACK */ |
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extern atomic_long_t tcp_memory_allocated; |
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extern struct percpu_counter tcp_sockets_allocated; |
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extern unsigned long tcp_memory_pressure; |
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/* optimized version of sk_under_memory_pressure() for TCP sockets */ |
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static inline bool tcp_under_memory_pressure(const struct sock *sk) |
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{ |
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if (mem_cgroup_sockets_enabled && sk->sk_memcg && |
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mem_cgroup_under_socket_pressure(sk->sk_memcg)) |
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return true; |
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return READ_ONCE(tcp_memory_pressure); |
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} |
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/* |
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* The next routines deal with comparing 32 bit unsigned ints |
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* and worry about wraparound (automatic with unsigned arithmetic). |
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*/ |
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static inline bool before(__u32 seq1, __u32 seq2) |
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{ |
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return (__s32)(seq1-seq2) < 0; |
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} |
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#define after(seq2, seq1) before(seq1, seq2) |
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/* is s2<=s1<=s3 ? */ |
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static inline bool between(__u32 seq1, __u32 seq2, __u32 seq3) |
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{ |
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return seq3 - seq2 >= seq1 - seq2; |
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} |
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static inline bool tcp_out_of_memory(struct sock *sk) |
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{ |
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if (sk->sk_wmem_queued > SOCK_MIN_SNDBUF && |
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sk_memory_allocated(sk) > sk_prot_mem_limits(sk, 2)) |
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return true; |
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return false; |
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} |
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void sk_forced_mem_schedule(struct sock *sk, int size); |
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static inline bool tcp_too_many_orphans(struct sock *sk, int shift) |
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{ |
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struct percpu_counter *ocp = sk->sk_prot->orphan_count; |
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int orphans = percpu_counter_read_positive(ocp); |
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if (orphans << shift > sysctl_tcp_max_orphans) { |
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orphans = percpu_counter_sum_positive(ocp); |
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if (orphans << shift > sysctl_tcp_max_orphans) |
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return true; |
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} |
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return false; |
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} |
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bool tcp_check_oom(struct sock *sk, int shift); |
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extern struct proto tcp_prot; |
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#define TCP_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.tcp_statistics, field) |
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#define __TCP_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.tcp_statistics, field) |
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#define TCP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->mib.tcp_statistics, field) |
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#define TCP_ADD_STATS(net, field, val) SNMP_ADD_STATS((net)->mib.tcp_statistics, field, val) |
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void tcp_tasklet_init(void); |
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int tcp_v4_err(struct sk_buff *skb, u32); |
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void tcp_shutdown(struct sock *sk, int how); |
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int tcp_v4_early_demux(struct sk_buff *skb); |
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int tcp_v4_rcv(struct sk_buff *skb); |
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void tcp_remove_empty_skb(struct sock *sk, struct sk_buff *skb); |
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int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw); |
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int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); |
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int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size); |
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int tcp_sendpage(struct sock *sk, struct page *page, int offset, size_t size, |
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int flags); |
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int tcp_sendpage_locked(struct sock *sk, struct page *page, int offset, |
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size_t size, int flags); |
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struct sk_buff *tcp_build_frag(struct sock *sk, int size_goal, int flags, |
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struct page *page, int offset, size_t *size); |
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ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, |
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size_t size, int flags); |
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int tcp_send_mss(struct sock *sk, int *size_goal, int flags); |
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void tcp_push(struct sock *sk, int flags, int mss_now, int nonagle, |
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int size_goal); |
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void tcp_release_cb(struct sock *sk); |
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void tcp_wfree(struct sk_buff *skb); |
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void tcp_write_timer_handler(struct sock *sk); |
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void tcp_delack_timer_handler(struct sock *sk); |
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int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg); |
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int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb); |
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void tcp_rcv_established(struct sock *sk, struct sk_buff *skb); |
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void tcp_rcv_space_adjust(struct sock *sk); |
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int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp); |
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void tcp_twsk_destructor(struct sock *sk); |
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ssize_t tcp_splice_read(struct socket *sk, loff_t *ppos, |
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struct pipe_inode_info *pipe, size_t len, |
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unsigned int flags); |
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void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks); |
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static inline void tcp_dec_quickack_mode(struct sock *sk, |
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const unsigned int pkts) |
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{ |
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struct inet_connection_sock *icsk = inet_csk(sk); |
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if (icsk->icsk_ack.quick) { |
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if (pkts >= icsk->icsk_ack.quick) { |
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icsk->icsk_ack.quick = 0; |
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/* Leaving quickack mode we deflate ATO. */ |
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icsk->icsk_ack.ato = TCP_ATO_MIN; |
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} else |
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icsk->icsk_ack.quick -= pkts; |
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} |
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} |
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#define TCP_ECN_OK 1 |
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#define TCP_ECN_QUEUE_CWR 2 |
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#define TCP_ECN_DEMAND_CWR 4 |
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#define TCP_ECN_SEEN 8 |
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enum tcp_tw_status { |
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TCP_TW_SUCCESS = 0, |
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TCP_TW_RST = 1, |
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TCP_TW_ACK = 2, |
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TCP_TW_SYN = 3 |
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}; |
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enum tcp_tw_status tcp_timewait_state_process(struct inet_timewait_sock *tw, |
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struct sk_buff *skb, |
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const struct tcphdr *th); |
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struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, |
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struct request_sock *req, bool fastopen, |
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bool *lost_race); |
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int tcp_child_process(struct sock *parent, struct sock *child, |
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struct sk_buff *skb); |
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void tcp_enter_loss(struct sock *sk); |
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void tcp_cwnd_reduction(struct sock *sk, int newly_acked_sacked, int newly_lost, int flag); |
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void tcp_clear_retrans(struct tcp_sock *tp); |
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void tcp_update_metrics(struct sock *sk); |
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void tcp_init_metrics(struct sock *sk); |
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void tcp_metrics_init(void); |
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bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst); |
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void __tcp_close(struct sock *sk, long timeout); |
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void tcp_close(struct sock *sk, long timeout); |
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void tcp_init_sock(struct sock *sk); |
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void tcp_init_transfer(struct sock *sk, int bpf_op, struct sk_buff *skb); |
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__poll_t tcp_poll(struct file *file, struct socket *sock, |
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struct poll_table_struct *wait); |
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int tcp_getsockopt(struct sock *sk, int level, int optname, |
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char __user *optval, int __user *optlen); |
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bool tcp_bpf_bypass_getsockopt(int level, int optname); |
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int tcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, |
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unsigned int optlen); |
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void tcp_set_keepalive(struct sock *sk, int val); |
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void tcp_syn_ack_timeout(const struct request_sock *req); |
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int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, |
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int flags, int *addr_len); |
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int tcp_set_rcvlowat(struct sock *sk, int val); |
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int tcp_set_window_clamp(struct sock *sk, int val); |
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void tcp_data_ready(struct sock *sk); |
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#ifdef CONFIG_MMU |
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int tcp_mmap(struct file *file, struct socket *sock, |
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struct vm_area_struct *vma); |
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#endif |
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void tcp_parse_options(const struct net *net, const struct sk_buff *skb, |
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struct tcp_options_received *opt_rx, |
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int estab, struct tcp_fastopen_cookie *foc); |
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const u8 *tcp_parse_md5sig_option(const struct tcphdr *th); |
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|
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/* |
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* BPF SKB-less helpers |
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*/ |
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u16 tcp_v4_get_syncookie(struct sock *sk, struct iphdr *iph, |
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struct tcphdr *th, u32 *cookie); |
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u16 tcp_v6_get_syncookie(struct sock *sk, struct ipv6hdr *iph, |
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struct tcphdr *th, u32 *cookie); |
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u16 tcp_get_syncookie_mss(struct request_sock_ops *rsk_ops, |
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const struct tcp_request_sock_ops *af_ops, |
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struct sock *sk, struct tcphdr *th); |
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/* |
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* TCP v4 functions exported for the inet6 API |
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*/ |
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void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb); |
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void tcp_v4_mtu_reduced(struct sock *sk); |
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void tcp_req_err(struct sock *sk, u32 seq, bool abort); |
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void tcp_ld_RTO_revert(struct sock *sk, u32 seq); |
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int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb); |
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struct sock *tcp_create_openreq_child(const struct sock *sk, |
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struct request_sock *req, |
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struct sk_buff *skb); |
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void tcp_ca_openreq_child(struct sock *sk, const struct dst_entry *dst); |
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struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, |
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struct request_sock *req, |
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struct dst_entry *dst, |
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struct request_sock *req_unhash, |
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bool *own_req); |
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int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); |
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int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); |
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int tcp_connect(struct sock *sk); |
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enum tcp_synack_type { |
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TCP_SYNACK_NORMAL, |
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TCP_SYNACK_FASTOPEN, |
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TCP_SYNACK_COOKIE, |
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}; |
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struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, |
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struct request_sock *req, |
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struct tcp_fastopen_cookie *foc, |
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enum tcp_synack_type synack_type, |
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struct sk_buff *syn_skb); |
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int tcp_disconnect(struct sock *sk, int flags); |
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void tcp_finish_connect(struct sock *sk, struct sk_buff *skb); |
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int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size); |
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void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb); |
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|
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/* From syncookies.c */ |
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struct sock *tcp_get_cookie_sock(struct sock *sk, struct sk_buff *skb, |
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struct request_sock *req, |
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struct dst_entry *dst, u32 tsoff); |
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int __cookie_v4_check(const struct iphdr *iph, const struct tcphdr *th, |
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u32 cookie); |
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struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb); |
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struct request_sock *cookie_tcp_reqsk_alloc(const struct request_sock_ops *ops, |
|
struct sock *sk, struct sk_buff *skb); |
|
#ifdef CONFIG_SYN_COOKIES |
|
|
|
/* Syncookies use a monotonic timer which increments every 60 seconds. |
|
* This counter is used both as a hash input and partially encoded into |
|
* the cookie value. A cookie is only validated further if the delta |
|
* between the current counter value and the encoded one is less than this, |
|
* i.e. a sent cookie is valid only at most for 2*60 seconds (or less if |
|
* the counter advances immediately after a cookie is generated). |
|
*/ |
|
#define MAX_SYNCOOKIE_AGE 2 |
|
#define TCP_SYNCOOKIE_PERIOD (60 * HZ) |
|
#define TCP_SYNCOOKIE_VALID (MAX_SYNCOOKIE_AGE * TCP_SYNCOOKIE_PERIOD) |
|
|
|
/* syncookies: remember time of last synqueue overflow |
|
* But do not dirty this field too often (once per second is enough) |
|
* It is racy as we do not hold a lock, but race is very minor. |
|
*/ |
|
static inline void tcp_synq_overflow(const struct sock *sk) |
|
{ |
|
unsigned int last_overflow; |
|
unsigned int now = jiffies; |
|
|
|
if (sk->sk_reuseport) { |
|
struct sock_reuseport *reuse; |
|
|
|
reuse = rcu_dereference(sk->sk_reuseport_cb); |
|
if (likely(reuse)) { |
|
last_overflow = READ_ONCE(reuse->synq_overflow_ts); |
|
if (!time_between32(now, last_overflow, |
|
last_overflow + HZ)) |
|
WRITE_ONCE(reuse->synq_overflow_ts, now); |
|
return; |
|
} |
|
} |
|
|
|
last_overflow = READ_ONCE(tcp_sk(sk)->rx_opt.ts_recent_stamp); |
|
if (!time_between32(now, last_overflow, last_overflow + HZ)) |
|
WRITE_ONCE(tcp_sk(sk)->rx_opt.ts_recent_stamp, now); |
|
} |
|
|
|
/* syncookies: no recent synqueue overflow on this listening socket? */ |
|
static inline bool tcp_synq_no_recent_overflow(const struct sock *sk) |
|
{ |
|
unsigned int last_overflow; |
|
unsigned int now = jiffies; |
|
|
|
if (sk->sk_reuseport) { |
|
struct sock_reuseport *reuse; |
|
|
|
reuse = rcu_dereference(sk->sk_reuseport_cb); |
|
if (likely(reuse)) { |
|
last_overflow = READ_ONCE(reuse->synq_overflow_ts); |
|
return !time_between32(now, last_overflow - HZ, |
|
last_overflow + |
|
TCP_SYNCOOKIE_VALID); |
|
} |
|
} |
|
|
|
last_overflow = READ_ONCE(tcp_sk(sk)->rx_opt.ts_recent_stamp); |
|
|
|
/* If last_overflow <= jiffies <= last_overflow + TCP_SYNCOOKIE_VALID, |
|
* then we're under synflood. However, we have to use |
|
* 'last_overflow - HZ' as lower bound. That's because a concurrent |
|
* tcp_synq_overflow() could update .ts_recent_stamp after we read |
|
* jiffies but before we store .ts_recent_stamp into last_overflow, |
|
* which could lead to rejecting a valid syncookie. |
|
*/ |
|
return !time_between32(now, last_overflow - HZ, |
|
last_overflow + TCP_SYNCOOKIE_VALID); |
|
} |
|
|
|
static inline u32 tcp_cookie_time(void) |
|
{ |
|
u64 val = get_jiffies_64(); |
|
|
|
do_div(val, TCP_SYNCOOKIE_PERIOD); |
|
return val; |
|
} |
|
|
|
u32 __cookie_v4_init_sequence(const struct iphdr *iph, const struct tcphdr *th, |
|
u16 *mssp); |
|
__u32 cookie_v4_init_sequence(const struct sk_buff *skb, __u16 *mss); |
|
u64 cookie_init_timestamp(struct request_sock *req, u64 now); |
|
bool cookie_timestamp_decode(const struct net *net, |
|
struct tcp_options_received *opt); |
|
bool cookie_ecn_ok(const struct tcp_options_received *opt, |
|
const struct net *net, const struct dst_entry *dst); |
|
|
|
/* From net/ipv6/syncookies.c */ |
|
int __cookie_v6_check(const struct ipv6hdr *iph, const struct tcphdr *th, |
|
u32 cookie); |
|
struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb); |
|
|
|
u32 __cookie_v6_init_sequence(const struct ipv6hdr *iph, |
|
const struct tcphdr *th, u16 *mssp); |
|
__u32 cookie_v6_init_sequence(const struct sk_buff *skb, __u16 *mss); |
|
#endif |
|
/* tcp_output.c */ |
|
|
|
void __tcp_push_pending_frames(struct sock *sk, unsigned int cur_mss, |
|
int nonagle); |
|
int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs); |
|
int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs); |
|
void tcp_retransmit_timer(struct sock *sk); |
|
void tcp_xmit_retransmit_queue(struct sock *); |
|
void tcp_simple_retransmit(struct sock *); |
|
void tcp_enter_recovery(struct sock *sk, bool ece_ack); |
|
int tcp_trim_head(struct sock *, struct sk_buff *, u32); |
|
enum tcp_queue { |
|
TCP_FRAG_IN_WRITE_QUEUE, |
|
TCP_FRAG_IN_RTX_QUEUE, |
|
}; |
|
int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue, |
|
struct sk_buff *skb, u32 len, |
|
unsigned int mss_now, gfp_t gfp); |
|
|
|
void tcp_send_probe0(struct sock *); |
|
void tcp_send_partial(struct sock *); |
|
int tcp_write_wakeup(struct sock *, int mib); |
|
void tcp_send_fin(struct sock *sk); |
|
void tcp_send_active_reset(struct sock *sk, gfp_t priority); |
|
int tcp_send_synack(struct sock *); |
|
void tcp_push_one(struct sock *, unsigned int mss_now); |
|
void __tcp_send_ack(struct sock *sk, u32 rcv_nxt); |
|
void tcp_send_ack(struct sock *sk); |
|
void tcp_send_delayed_ack(struct sock *sk); |
|
void tcp_send_loss_probe(struct sock *sk); |
|
bool tcp_schedule_loss_probe(struct sock *sk, bool advancing_rto); |
|
void tcp_skb_collapse_tstamp(struct sk_buff *skb, |
|
const struct sk_buff *next_skb); |
|
|
|
/* tcp_input.c */ |
|
void tcp_rearm_rto(struct sock *sk); |
|
void tcp_synack_rtt_meas(struct sock *sk, struct request_sock *req); |
|
void tcp_reset(struct sock *sk, struct sk_buff *skb); |
|
void tcp_skb_mark_lost_uncond_verify(struct tcp_sock *tp, struct sk_buff *skb); |
|
void tcp_fin(struct sock *sk); |
|
|
|
/* tcp_timer.c */ |
|
void tcp_init_xmit_timers(struct sock *); |
|
static inline void tcp_clear_xmit_timers(struct sock *sk) |
|
{ |
|
if (hrtimer_try_to_cancel(&tcp_sk(sk)->pacing_timer) == 1) |
|
__sock_put(sk); |
|
|
|
if (hrtimer_try_to_cancel(&tcp_sk(sk)->compressed_ack_timer) == 1) |
|
__sock_put(sk); |
|
|
|
inet_csk_clear_xmit_timers(sk); |
|
} |
|
|
|
unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu); |
|
unsigned int tcp_current_mss(struct sock *sk); |
|
u32 tcp_clamp_probe0_to_user_timeout(const struct sock *sk, u32 when); |
|
|
|
/* Bound MSS / TSO packet size with the half of the window */ |
|
static inline int tcp_bound_to_half_wnd(struct tcp_sock *tp, int pktsize) |
|
{ |
|
int cutoff; |
|
|
|
/* When peer uses tiny windows, there is no use in packetizing |
|
* to sub-MSS pieces for the sake of SWS or making sure there |
|
* are enough packets in the pipe for fast recovery. |
|
* |
|
* On the other hand, for extremely large MSS devices, handling |
|
* smaller than MSS windows in this way does make sense. |
|
*/ |
|
if (tp->max_window > TCP_MSS_DEFAULT) |
|
cutoff = (tp->max_window >> 1); |
|
else |
|
cutoff = tp->max_window; |
|
|
|
if (cutoff && pktsize > cutoff) |
|
return max_t(int, cutoff, 68U - tp->tcp_header_len); |
|
else |
|
return pktsize; |
|
} |
|
|
|
/* tcp.c */ |
|
void tcp_get_info(struct sock *, struct tcp_info *); |
|
|
|
/* Read 'sendfile()'-style from a TCP socket */ |
|
int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, |
|
sk_read_actor_t recv_actor); |
|
|
|
void tcp_initialize_rcv_mss(struct sock *sk); |
|
|
|
int tcp_mtu_to_mss(struct sock *sk, int pmtu); |
|
int tcp_mss_to_mtu(struct sock *sk, int mss); |
|
void tcp_mtup_init(struct sock *sk); |
|
|
|
static inline void tcp_bound_rto(const struct sock *sk) |
|
{ |
|
if (inet_csk(sk)->icsk_rto > TCP_RTO_MAX) |
|
inet_csk(sk)->icsk_rto = TCP_RTO_MAX; |
|
} |
|
|
|
static inline u32 __tcp_set_rto(const struct tcp_sock *tp) |
|
{ |
|
return usecs_to_jiffies((tp->srtt_us >> 3) + tp->rttvar_us); |
|
} |
|
|
|
static inline void __tcp_fast_path_on(struct tcp_sock *tp, u32 snd_wnd) |
|
{ |
|
tp->pred_flags = htonl((tp->tcp_header_len << 26) | |
|
ntohl(TCP_FLAG_ACK) | |
|
snd_wnd); |
|
} |
|
|
|
static inline void tcp_fast_path_on(struct tcp_sock *tp) |
|
{ |
|
__tcp_fast_path_on(tp, tp->snd_wnd >> tp->rx_opt.snd_wscale); |
|
} |
|
|
|
static inline void tcp_fast_path_check(struct sock *sk) |
|
{ |
|
struct tcp_sock *tp = tcp_sk(sk); |
|
|
|
if (RB_EMPTY_ROOT(&tp->out_of_order_queue) && |
|
tp->rcv_wnd && |
|
atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf && |
|
!tp->urg_data) |
|
tcp_fast_path_on(tp); |
|
} |
|
|
|
/* Compute the actual rto_min value */ |
|
static inline u32 tcp_rto_min(struct sock *sk) |
|
{ |
|
const struct dst_entry *dst = __sk_dst_get(sk); |
|
u32 rto_min = inet_csk(sk)->icsk_rto_min; |
|
|
|
if (dst && dst_metric_locked(dst, RTAX_RTO_MIN)) |
|
rto_min = dst_metric_rtt(dst, RTAX_RTO_MIN); |
|
return rto_min; |
|
} |
|
|
|
static inline u32 tcp_rto_min_us(struct sock *sk) |
|
{ |
|
return jiffies_to_usecs(tcp_rto_min(sk)); |
|
} |
|
|
|
static inline bool tcp_ca_dst_locked(const struct dst_entry *dst) |
|
{ |
|
return dst_metric_locked(dst, RTAX_CC_ALGO); |
|
} |
|
|
|
/* Minimum RTT in usec. ~0 means not available. */ |
|
static inline u32 tcp_min_rtt(const struct tcp_sock *tp) |
|
{ |
|
return minmax_get(&tp->rtt_min); |
|
} |
|
|
|
/* Compute the actual receive window we are currently advertising. |
|
* Rcv_nxt can be after the window if our peer push more data |
|
* than the offered window. |
|
*/ |
|
static inline u32 tcp_receive_window(const struct tcp_sock *tp) |
|
{ |
|
s32 win = tp->rcv_wup + tp->rcv_wnd - tp->rcv_nxt; |
|
|
|
if (win < 0) |
|
win = 0; |
|
return (u32) win; |
|
} |
|
|
|
/* Choose a new window, without checks for shrinking, and without |
|
* scaling applied to the result. The caller does these things |
|
* if necessary. This is a "raw" window selection. |
|
*/ |
|
u32 __tcp_select_window(struct sock *sk); |
|
|
|
void tcp_send_window_probe(struct sock *sk); |
|
|
|
/* TCP uses 32bit jiffies to save some space. |
|
* Note that this is different from tcp_time_stamp, which |
|
* historically has been the same until linux-4.13. |
|
*/ |
|
#define tcp_jiffies32 ((u32)jiffies) |
|
|
|
/* |
|
* Deliver a 32bit value for TCP timestamp option (RFC 7323) |
|
* It is no longer tied to jiffies, but to 1 ms clock. |
|
* Note: double check if you want to use tcp_jiffies32 instead of this. |
|
*/ |
|
#define TCP_TS_HZ 1000 |
|
|
|
static inline u64 tcp_clock_ns(void) |
|
{ |
|
return ktime_get_ns(); |
|
} |
|
|
|
static inline u64 tcp_clock_us(void) |
|
{ |
|
return div_u64(tcp_clock_ns(), NSEC_PER_USEC); |
|
} |
|
|
|
/* This should only be used in contexts where tp->tcp_mstamp is up to date */ |
|
static inline u32 tcp_time_stamp(const struct tcp_sock *tp) |
|
{ |
|
return div_u64(tp->tcp_mstamp, USEC_PER_SEC / TCP_TS_HZ); |
|
} |
|
|
|
/* Convert a nsec timestamp into TCP TSval timestamp (ms based currently) */ |
|
static inline u32 tcp_ns_to_ts(u64 ns) |
|
{ |
|
return div_u64(ns, NSEC_PER_SEC / TCP_TS_HZ); |
|
} |
|
|
|
/* Could use tcp_clock_us() / 1000, but this version uses a single divide */ |
|
static inline u32 tcp_time_stamp_raw(void) |
|
{ |
|
return tcp_ns_to_ts(tcp_clock_ns()); |
|
} |
|
|
|
void tcp_mstamp_refresh(struct tcp_sock *tp); |
|
|
|
static inline u32 tcp_stamp_us_delta(u64 t1, u64 t0) |
|
{ |
|
return max_t(s64, t1 - t0, 0); |
|
} |
|
|
|
static inline u32 tcp_skb_timestamp(const struct sk_buff *skb) |
|
{ |
|
return tcp_ns_to_ts(skb->skb_mstamp_ns); |
|
} |
|
|
|
/* provide the departure time in us unit */ |
|
static inline u64 tcp_skb_timestamp_us(const struct sk_buff *skb) |
|
{ |
|
return div_u64(skb->skb_mstamp_ns, NSEC_PER_USEC); |
|
} |
|
|
|
|
|
#define tcp_flag_byte(th) (((u_int8_t *)th)[13]) |
|
|
|
#define TCPHDR_FIN 0x01 |
|
#define TCPHDR_SYN 0x02 |
|
#define TCPHDR_RST 0x04 |
|
#define TCPHDR_PSH 0x08 |
|
#define TCPHDR_ACK 0x10 |
|
#define TCPHDR_URG 0x20 |
|
#define TCPHDR_ECE 0x40 |
|
#define TCPHDR_CWR 0x80 |
|
|
|
#define TCPHDR_SYN_ECN (TCPHDR_SYN | TCPHDR_ECE | TCPHDR_CWR) |
|
|
|
/* This is what the send packet queuing engine uses to pass |
|
* TCP per-packet control information to the transmission code. |
|
* We also store the host-order sequence numbers in here too. |
|
* This is 44 bytes if IPV6 is enabled. |
|
* If this grows please adjust skbuff.h:skbuff->cb[xxx] size appropriately. |
|
*/ |
|
struct tcp_skb_cb { |
|
__u32 seq; /* Starting sequence number */ |
|
__u32 end_seq; /* SEQ + FIN + SYN + datalen */ |
|
union { |
|
/* Note : tcp_tw_isn is used in input path only |
|
* (isn chosen by tcp_timewait_state_process()) |
|
* |
|
* tcp_gso_segs/size are used in write queue only, |
|
* cf tcp_skb_pcount()/tcp_skb_mss() |
|
*/ |
|
__u32 tcp_tw_isn; |
|
struct { |
|
u16 tcp_gso_segs; |
|
u16 tcp_gso_size; |
|
}; |
|
}; |
|
__u8 tcp_flags; /* TCP header flags. (tcp[13]) */ |
|
|
|
__u8 sacked; /* State flags for SACK. */ |
|
#define TCPCB_SACKED_ACKED 0x01 /* SKB ACK'd by a SACK block */ |
|
#define TCPCB_SACKED_RETRANS 0x02 /* SKB retransmitted */ |
|
#define TCPCB_LOST 0x04 /* SKB is lost */ |
|
#define TCPCB_TAGBITS 0x07 /* All tag bits */ |
|
#define TCPCB_REPAIRED 0x10 /* SKB repaired (no skb_mstamp_ns) */ |
|
#define TCPCB_EVER_RETRANS 0x80 /* Ever retransmitted frame */ |
|
#define TCPCB_RETRANS (TCPCB_SACKED_RETRANS|TCPCB_EVER_RETRANS| \ |
|
TCPCB_REPAIRED) |
|
|
|
__u8 ip_dsfield; /* IPv4 tos or IPv6 dsfield */ |
|
__u8 txstamp_ack:1, /* Record TX timestamp for ack? */ |
|
eor:1, /* Is skb MSG_EOR marked? */ |
|
has_rxtstamp:1, /* SKB has a RX timestamp */ |
|
unused:5; |
|
__u32 ack_seq; /* Sequence number ACK'd */ |
|
union { |
|
struct { |
|
/* There is space for up to 24 bytes */ |
|
__u32 in_flight:30,/* Bytes in flight at transmit */ |
|
is_app_limited:1, /* cwnd not fully used? */ |
|
unused:1; |
|
/* pkts S/ACKed so far upon tx of skb, incl retrans: */ |
|
__u32 delivered; |
|
/* start of send pipeline phase */ |
|
u64 first_tx_mstamp; |
|
/* when we reached the "delivered" count */ |
|
u64 delivered_mstamp; |
|
} tx; /* only used for outgoing skbs */ |
|
union { |
|
struct inet_skb_parm h4; |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
struct inet6_skb_parm h6; |
|
#endif |
|
} header; /* For incoming skbs */ |
|
struct { |
|
__u32 flags; |
|
struct sock *sk_redir; |
|
void *data_end; |
|
} bpf; |
|
}; |
|
}; |
|
|
|
#define TCP_SKB_CB(__skb) ((struct tcp_skb_cb *)&((__skb)->cb[0])) |
|
|
|
static inline void bpf_compute_data_end_sk_skb(struct sk_buff *skb) |
|
{ |
|
TCP_SKB_CB(skb)->bpf.data_end = skb->data + skb_headlen(skb); |
|
} |
|
|
|
static inline bool tcp_skb_bpf_ingress(const struct sk_buff *skb) |
|
{ |
|
return TCP_SKB_CB(skb)->bpf.flags & BPF_F_INGRESS; |
|
} |
|
|
|
static inline struct sock *tcp_skb_bpf_redirect_fetch(struct sk_buff *skb) |
|
{ |
|
return TCP_SKB_CB(skb)->bpf.sk_redir; |
|
} |
|
|
|
static inline void tcp_skb_bpf_redirect_clear(struct sk_buff *skb) |
|
{ |
|
TCP_SKB_CB(skb)->bpf.sk_redir = NULL; |
|
} |
|
|
|
extern const struct inet_connection_sock_af_ops ipv4_specific; |
|
|
|
#if IS_ENABLED(CONFIG_IPV6) |
|
/* This is the variant of inet6_iif() that must be used by TCP, |
|
* as TCP moves IP6CB into a different location in skb->cb[] |
|
*/ |
|
static inline int tcp_v6_iif(const struct sk_buff *skb) |
|
{ |
|
return TCP_SKB_CB(skb)->header.h6.iif; |
|
} |
|
|
|
static inline int tcp_v6_iif_l3_slave(const struct sk_buff *skb) |
|
{ |
|
bool l3_slave = ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags); |
|
|
|
return l3_slave ? skb->skb_iif : TCP_SKB_CB(skb)->header.h6.iif; |
|
} |
|
|
|
/* TCP_SKB_CB reference means this can not be used from early demux */ |
|
static inline int tcp_v6_sdif(const struct sk_buff *skb) |
|
{ |
|
#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) |
|
if (skb && ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags)) |
|
return TCP_SKB_CB(skb)->header.h6.iif; |
|
#endif |
|
return 0; |
|
} |
|
|
|
extern const struct inet_connection_sock_af_ops ipv6_specific; |
|
|
|
INDIRECT_CALLABLE_DECLARE(void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)); |
|
INDIRECT_CALLABLE_DECLARE(int tcp_v6_rcv(struct sk_buff *skb)); |
|
INDIRECT_CALLABLE_DECLARE(void tcp_v6_early_demux(struct sk_buff *skb)); |
|
|
|
#endif |
|
|
|
/* TCP_SKB_CB reference means this can not be used from early demux */ |
|
static inline int tcp_v4_sdif(struct sk_buff *skb) |
|
{ |
|
#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) |
|
if (skb && ipv4_l3mdev_skb(TCP_SKB_CB(skb)->header.h4.flags)) |
|
return TCP_SKB_CB(skb)->header.h4.iif; |
|
#endif |
|
return 0; |
|
} |
|
|
|
/* Due to TSO, an SKB can be composed of multiple actual |
|
* packets. To keep these tracked properly, we use this. |
|
*/ |
|
static inline int tcp_skb_pcount(const struct sk_buff *skb) |
|
{ |
|
return TCP_SKB_CB(skb)->tcp_gso_segs; |
|
} |
|
|
|
static inline void tcp_skb_pcount_set(struct sk_buff *skb, int segs) |
|
{ |
|
TCP_SKB_CB(skb)->tcp_gso_segs = segs; |
|
} |
|
|
|
static inline void tcp_skb_pcount_add(struct sk_buff *skb, int segs) |
|
{ |
|
TCP_SKB_CB(skb)->tcp_gso_segs += segs; |
|
} |
|
|
|
/* This is valid iff skb is in write queue and tcp_skb_pcount() > 1. */ |
|
static inline int tcp_skb_mss(const struct sk_buff *skb) |
|
{ |
|
return TCP_SKB_CB(skb)->tcp_gso_size; |
|
} |
|
|
|
static inline bool tcp_skb_can_collapse_to(const struct sk_buff *skb) |
|
{ |
|
return likely(!TCP_SKB_CB(skb)->eor); |
|
} |
|
|
|
static inline bool tcp_skb_can_collapse(const struct sk_buff *to, |
|
const struct sk_buff *from) |
|
{ |
|
return likely(tcp_skb_can_collapse_to(to) && |
|
mptcp_skb_can_collapse(to, from)); |
|
} |
|
|
|
/* Events passed to congestion control interface */ |
|
enum tcp_ca_event { |
|
CA_EVENT_TX_START, /* first transmit when no packets in flight */ |
|
CA_EVENT_CWND_RESTART, /* congestion window restart */ |
|
CA_EVENT_COMPLETE_CWR, /* end of congestion recovery */ |
|
CA_EVENT_LOSS, /* loss timeout */ |
|
CA_EVENT_ECN_NO_CE, /* ECT set, but not CE marked */ |
|
CA_EVENT_ECN_IS_CE, /* received CE marked IP packet */ |
|
}; |
|
|
|
/* Information about inbound ACK, passed to cong_ops->in_ack_event() */ |
|
enum tcp_ca_ack_event_flags { |
|
CA_ACK_SLOWPATH = (1 << 0), /* In slow path processing */ |
|
CA_ACK_WIN_UPDATE = (1 << 1), /* ACK updated window */ |
|
CA_ACK_ECE = (1 << 2), /* ECE bit is set on ack */ |
|
}; |
|
|
|
/* |
|
* Interface for adding new TCP congestion control handlers |
|
*/ |
|
#define TCP_CA_NAME_MAX 16 |
|
#define TCP_CA_MAX 128 |
|
#define TCP_CA_BUF_MAX (TCP_CA_NAME_MAX*TCP_CA_MAX) |
|
|
|
#define TCP_CA_UNSPEC 0 |
|
|
|
/* Algorithm can be set on socket without CAP_NET_ADMIN privileges */ |
|
#define TCP_CONG_NON_RESTRICTED 0x1 |
|
/* Requires ECN/ECT set on all packets */ |
|
#define TCP_CONG_NEEDS_ECN 0x2 |
|
#define TCP_CONG_MASK (TCP_CONG_NON_RESTRICTED | TCP_CONG_NEEDS_ECN) |
|
|
|
union tcp_cc_info; |
|
|
|
struct ack_sample { |
|
u32 pkts_acked; |
|
s32 rtt_us; |
|
u32 in_flight; |
|
}; |
|
|
|
/* A rate sample measures the number of (original/retransmitted) data |
|
* packets delivered "delivered" over an interval of time "interval_us". |
|
* The tcp_rate.c code fills in the rate sample, and congestion |
|
* control modules that define a cong_control function to run at the end |
|
* of ACK processing can optionally chose to consult this sample when |
|
* setting cwnd and pacing rate. |
|
* A sample is invalid if "delivered" or "interval_us" is negative. |
|
*/ |
|
struct rate_sample { |
|
u64 prior_mstamp; /* starting timestamp for interval */ |
|
u32 prior_delivered; /* tp->delivered at "prior_mstamp" */ |
|
s32 delivered; /* number of packets delivered over interval */ |
|
long interval_us; /* time for tp->delivered to incr "delivered" */ |
|
u32 snd_interval_us; /* snd interval for delivered packets */ |
|
u32 rcv_interval_us; /* rcv interval for delivered packets */ |
|
long rtt_us; /* RTT of last (S)ACKed packet (or -1) */ |
|
int losses; /* number of packets marked lost upon ACK */ |
|
u32 acked_sacked; /* number of packets newly (S)ACKed upon ACK */ |
|
u32 prior_in_flight; /* in flight before this ACK */ |
|
bool is_app_limited; /* is sample from packet with bubble in pipe? */ |
|
bool is_retrans; /* is sample from retransmission? */ |
|
bool is_ack_delayed; /* is this (likely) a delayed ACK? */ |
|
}; |
|
|
|
struct tcp_congestion_ops { |
|
struct list_head list; |
|
u32 key; |
|
u32 flags; |
|
|
|
/* initialize private data (optional) */ |
|
void (*init)(struct sock *sk); |
|
/* cleanup private data (optional) */ |
|
void (*release)(struct sock *sk); |
|
|
|
/* return slow start threshold (required) */ |
|
u32 (*ssthresh)(struct sock *sk); |
|
/* do new cwnd calculation (required) */ |
|
void (*cong_avoid)(struct sock *sk, u32 ack, u32 acked); |
|
/* call before changing ca_state (optional) */ |
|
void (*set_state)(struct sock *sk, u8 new_state); |
|
/* call when cwnd event occurs (optional) */ |
|
void (*cwnd_event)(struct sock *sk, enum tcp_ca_event ev); |
|
/* call when ack arrives (optional) */ |
|
void (*in_ack_event)(struct sock *sk, u32 flags); |
|
/* new value of cwnd after loss (required) */ |
|
u32 (*undo_cwnd)(struct sock *sk); |
|
/* hook for packet ack accounting (optional) */ |
|
void (*pkts_acked)(struct sock *sk, const struct ack_sample *sample); |
|
/* override sysctl_tcp_min_tso_segs */ |
|
u32 (*min_tso_segs)(struct sock *sk); |
|
/* returns the multiplier used in tcp_sndbuf_expand (optional) */ |
|
u32 (*sndbuf_expand)(struct sock *sk); |
|
/* call when packets are delivered to update cwnd and pacing rate, |
|
* after all the ca_state processing. (optional) |
|
*/ |
|
void (*cong_control)(struct sock *sk, const struct rate_sample *rs); |
|
/* get info for inet_diag (optional) */ |
|
size_t (*get_info)(struct sock *sk, u32 ext, int *attr, |
|
union tcp_cc_info *info); |
|
|
|
char name[TCP_CA_NAME_MAX]; |
|
struct module *owner; |
|
}; |
|
|
|
int tcp_register_congestion_control(struct tcp_congestion_ops *type); |
|
void tcp_unregister_congestion_control(struct tcp_congestion_ops *type); |
|
|
|
void tcp_assign_congestion_control(struct sock *sk); |
|
void tcp_init_congestion_control(struct sock *sk); |
|
void tcp_cleanup_congestion_control(struct sock *sk); |
|
int tcp_set_default_congestion_control(struct net *net, const char *name); |
|
void tcp_get_default_congestion_control(struct net *net, char *name); |
|
void tcp_get_available_congestion_control(char *buf, size_t len); |
|
void tcp_get_allowed_congestion_control(char *buf, size_t len); |
|
int tcp_set_allowed_congestion_control(char *allowed); |
|
int tcp_set_congestion_control(struct sock *sk, const char *name, bool load, |
|
bool cap_net_admin); |
|
u32 tcp_slow_start(struct tcp_sock *tp, u32 acked); |
|
void tcp_cong_avoid_ai(struct tcp_sock *tp, u32 w, u32 acked); |
|
|
|
u32 tcp_reno_ssthresh(struct sock *sk); |
|
u32 tcp_reno_undo_cwnd(struct sock *sk); |
|
void tcp_reno_cong_avoid(struct sock *sk, u32 ack, u32 acked); |
|
extern struct tcp_congestion_ops tcp_reno; |
|
|
|
struct tcp_congestion_ops *tcp_ca_find(const char *name); |
|
struct tcp_congestion_ops *tcp_ca_find_key(u32 key); |
|
u32 tcp_ca_get_key_by_name(struct net *net, const char *name, bool *ecn_ca); |
|
#ifdef CONFIG_INET |
|
char *tcp_ca_get_name_by_key(u32 key, char *buffer); |
|
#else |
|
static inline char *tcp_ca_get_name_by_key(u32 key, char *buffer) |
|
{ |
|
return NULL; |
|
} |
|
#endif |
|
|
|
static inline bool tcp_ca_needs_ecn(const struct sock *sk) |
|
{ |
|
const struct inet_connection_sock *icsk = inet_csk(sk); |
|
|
|
return icsk->icsk_ca_ops->flags & TCP_CONG_NEEDS_ECN; |
|
} |
|
|
|
static inline void tcp_set_ca_state(struct sock *sk, const u8 ca_state) |
|
{ |
|
struct inet_connection_sock *icsk = inet_csk(sk); |
|
|
|
if (icsk->icsk_ca_ops->set_state) |
|
icsk->icsk_ca_ops->set_state(sk, ca_state); |
|
icsk->icsk_ca_state = ca_state; |
|
} |
|
|
|
static inline void tcp_ca_event(struct sock *sk, const enum tcp_ca_event event) |
|
{ |
|
const struct inet_connection_sock *icsk = inet_csk(sk); |
|
|
|
if (icsk->icsk_ca_ops->cwnd_event) |
|
icsk->icsk_ca_ops->cwnd_event(sk, event); |
|
} |
|
|
|
/* From tcp_rate.c */ |
|
void tcp_rate_skb_sent(struct sock *sk, struct sk_buff *skb); |
|
void tcp_rate_skb_delivered(struct sock *sk, struct sk_buff *skb, |
|
struct rate_sample *rs); |
|
void tcp_rate_gen(struct sock *sk, u32 delivered, u32 lost, |
|
bool is_sack_reneg, struct rate_sample *rs); |
|
void tcp_rate_check_app_limited(struct sock *sk); |
|
|
|
/* These functions determine how the current flow behaves in respect of SACK |
|
* handling. SACK is negotiated with the peer, and therefore it can vary |
|
* between different flows. |
|
* |
|
* tcp_is_sack - SACK enabled |
|
* tcp_is_reno - No SACK |
|
*/ |
|
static inline int tcp_is_sack(const struct tcp_sock *tp) |
|
{ |
|
return likely(tp->rx_opt.sack_ok); |
|
} |
|
|
|
static inline bool tcp_is_reno(const struct tcp_sock *tp) |
|
{ |
|
return !tcp_is_sack(tp); |
|
} |
|
|
|
static inline unsigned int tcp_left_out(const struct tcp_sock *tp) |
|
{ |
|
return tp->sacked_out + tp->lost_out; |
|
} |
|
|
|
/* This determines how many packets are "in the network" to the best |
|
* of our knowledge. In many cases it is conservative, but where |
|
* detailed information is available from the receiver (via SACK |
|
* blocks etc.) we can make more aggressive calculations. |
|
* |
|
* Use this for decisions involving congestion control, use just |
|
* tp->packets_out to determine if the send queue is empty or not. |
|
* |
|
* Read this equation as: |
|
* |
|
* "Packets sent once on transmission queue" MINUS |
|
* "Packets left network, but not honestly ACKed yet" PLUS |
|
* "Packets fast retransmitted" |
|
*/ |
|
static inline unsigned int tcp_packets_in_flight(const struct tcp_sock *tp) |
|
{ |
|
return tp->packets_out - tcp_left_out(tp) + tp->retrans_out; |
|
} |
|
|
|
#define TCP_INFINITE_SSTHRESH 0x7fffffff |
|
|
|
static inline bool tcp_in_slow_start(const struct tcp_sock *tp) |
|
{ |
|
return tp->snd_cwnd < tp->snd_ssthresh; |
|
} |
|
|
|
static inline bool tcp_in_initial_slowstart(const struct tcp_sock *tp) |
|
{ |
|
return tp->snd_ssthresh >= TCP_INFINITE_SSTHRESH; |
|
} |
|
|
|
static inline bool tcp_in_cwnd_reduction(const struct sock *sk) |
|
{ |
|
return (TCPF_CA_CWR | TCPF_CA_Recovery) & |
|
(1 << inet_csk(sk)->icsk_ca_state); |
|
} |
|
|
|
/* If cwnd > ssthresh, we may raise ssthresh to be half-way to cwnd. |
|
* The exception is cwnd reduction phase, when cwnd is decreasing towards |
|
* ssthresh. |
|
*/ |
|
static inline __u32 tcp_current_ssthresh(const struct sock *sk) |
|
{ |
|
const struct tcp_sock *tp = tcp_sk(sk); |
|
|
|
if (tcp_in_cwnd_reduction(sk)) |
|
return tp->snd_ssthresh; |
|
else |
|
return max(tp->snd_ssthresh, |
|
((tp->snd_cwnd >> 1) + |
|
(tp->snd_cwnd >> 2))); |
|
} |
|
|
|
/* Use define here intentionally to get WARN_ON location shown at the caller */ |
|
#define tcp_verify_left_out(tp) WARN_ON(tcp_left_out(tp) > tp->packets_out) |
|
|
|
void tcp_enter_cwr(struct sock *sk); |
|
__u32 tcp_init_cwnd(const struct tcp_sock *tp, const struct dst_entry *dst); |
|
|
|
/* The maximum number of MSS of available cwnd for which TSO defers |
|
* sending if not using sysctl_tcp_tso_win_divisor. |
|
*/ |
|
static inline __u32 tcp_max_tso_deferred_mss(const struct tcp_sock *tp) |
|
{ |
|
return 3; |
|
} |
|
|
|
/* Returns end sequence number of the receiver's advertised window */ |
|
static inline u32 tcp_wnd_end(const struct tcp_sock *tp) |
|
{ |
|
return tp->snd_una + tp->snd_wnd; |
|
} |
|
|
|
/* We follow the spirit of RFC2861 to validate cwnd but implement a more |
|
* flexible approach. The RFC suggests cwnd should not be raised unless |
|
* it was fully used previously. And that's exactly what we do in |
|
* congestion avoidance mode. But in slow start we allow cwnd to grow |
|
* as long as the application has used half the cwnd. |
|
* Example : |
|
* cwnd is 10 (IW10), but application sends 9 frames. |
|
* We allow cwnd to reach 18 when all frames are ACKed. |
|
* This check is safe because it's as aggressive as slow start which already |
|
* risks 100% overshoot. The advantage is that we discourage application to |
|
* either send more filler packets or data to artificially blow up the cwnd |
|
* usage, and allow application-limited process to probe bw more aggressively. |
|
*/ |
|
static inline bool tcp_is_cwnd_limited(const struct sock *sk) |
|
{ |
|
const struct tcp_sock *tp = tcp_sk(sk); |
|
|
|
/* If in slow start, ensure cwnd grows to twice what was ACKed. */ |
|
if (tcp_in_slow_start(tp)) |
|
return tp->snd_cwnd < 2 * tp->max_packets_out; |
|
|
|
return tp->is_cwnd_limited; |
|
} |
|
|
|
/* BBR congestion control needs pacing. |
|
* Same remark for SO_MAX_PACING_RATE. |
|
* sch_fq packet scheduler is efficiently handling pacing, |
|
* but is not always installed/used. |
|
* Return true if TCP stack should pace packets itself. |
|
*/ |
|
static inline bool tcp_needs_internal_pacing(const struct sock *sk) |
|
{ |
|
return smp_load_acquire(&sk->sk_pacing_status) == SK_PACING_NEEDED; |
|
} |
|
|
|
/* Estimates in how many jiffies next packet for this flow can be sent. |
|
* Scheduling a retransmit timer too early would be silly. |
|
*/ |
|
static inline unsigned long tcp_pacing_delay(const struct sock *sk) |
|
{ |
|
s64 delay = tcp_sk(sk)->tcp_wstamp_ns - tcp_sk(sk)->tcp_clock_cache; |
|
|
|
return delay > 0 ? nsecs_to_jiffies(delay) : 0; |
|
} |
|
|
|
static inline void tcp_reset_xmit_timer(struct sock *sk, |
|
const int what, |
|
unsigned long when, |
|
const unsigned long max_when) |
|
{ |
|
inet_csk_reset_xmit_timer(sk, what, when + tcp_pacing_delay(sk), |
|
max_when); |
|
} |
|
|
|
/* Something is really bad, we could not queue an additional packet, |
|
* because qdisc is full or receiver sent a 0 window, or we are paced. |
|
* We do not want to add fuel to the fire, or abort too early, |
|
* so make sure the timer we arm now is at least 200ms in the future, |
|
* regardless of current icsk_rto value (as it could be ~2ms) |
|
*/ |
|
static inline unsigned long tcp_probe0_base(const struct sock *sk) |
|
{ |
|
return max_t(unsigned long, inet_csk(sk)->icsk_rto, TCP_RTO_MIN); |
|
} |
|
|
|
/* Variant of inet_csk_rto_backoff() used for zero window probes */ |
|
static inline unsigned long tcp_probe0_when(const struct sock *sk, |
|
unsigned long max_when) |
|
{ |
|
u8 backoff = min_t(u8, ilog2(TCP_RTO_MAX / TCP_RTO_MIN) + 1, |
|
inet_csk(sk)->icsk_backoff); |
|
u64 when = (u64)tcp_probe0_base(sk) << backoff; |
|
|
|
return (unsigned long)min_t(u64, when, max_when); |
|
} |
|
|
|
static inline void tcp_check_probe_timer(struct sock *sk) |
|
{ |
|
if (!tcp_sk(sk)->packets_out && !inet_csk(sk)->icsk_pending) |
|
tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0, |
|
tcp_probe0_base(sk), TCP_RTO_MAX); |
|
} |
|
|
|
static inline void tcp_init_wl(struct tcp_sock *tp, u32 seq) |
|
{ |
|
tp->snd_wl1 = seq; |
|
} |
|
|
|
static inline void tcp_update_wl(struct tcp_sock *tp, u32 seq) |
|
{ |
|
tp->snd_wl1 = seq; |
|
} |
|
|
|
/* |
|
* Calculate(/check) TCP checksum |
|
*/ |
|
static inline __sum16 tcp_v4_check(int len, __be32 saddr, |
|
__be32 daddr, __wsum base) |
|
{ |
|
return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_TCP, base); |
|
} |
|
|
|
static inline bool tcp_checksum_complete(struct sk_buff *skb) |
|
{ |
|
return !skb_csum_unnecessary(skb) && |
|
__skb_checksum_complete(skb); |
|
} |
|
|
|
bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb); |
|
int tcp_filter(struct sock *sk, struct sk_buff *skb); |
|
void tcp_set_state(struct sock *sk, int state); |
|
void tcp_done(struct sock *sk); |
|
int tcp_abort(struct sock *sk, int err); |
|
|
|
static inline void tcp_sack_reset(struct tcp_options_received *rx_opt) |
|
{ |
|
rx_opt->dsack = 0; |
|
rx_opt->num_sacks = 0; |
|
} |
|
|
|
void tcp_cwnd_restart(struct sock *sk, s32 delta); |
|
|
|
static inline void tcp_slow_start_after_idle_check(struct sock *sk) |
|
{ |
|
const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops; |
|
struct tcp_sock *tp = tcp_sk(sk); |
|
s32 delta; |
|
|
|
if (!sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle || tp->packets_out || |
|
ca_ops->cong_control) |
|
return; |
|
delta = tcp_jiffies32 - tp->lsndtime; |
|
if (delta > inet_csk(sk)->icsk_rto) |
|
tcp_cwnd_restart(sk, delta); |
|
} |
|
|
|
/* Determine a window scaling and initial window to offer. */ |
|
void tcp_select_initial_window(const struct sock *sk, int __space, |
|
__u32 mss, __u32 *rcv_wnd, |
|
__u32 *window_clamp, int wscale_ok, |
|
__u8 *rcv_wscale, __u32 init_rcv_wnd); |
|
|
|
static inline int tcp_win_from_space(const struct sock *sk, int space) |
|
{ |
|
int tcp_adv_win_scale = sock_net(sk)->ipv4.sysctl_tcp_adv_win_scale; |
|
|
|
return tcp_adv_win_scale <= 0 ? |
|
(space>>(-tcp_adv_win_scale)) : |
|
space - (space>>tcp_adv_win_scale); |
|
} |
|
|
|
/* Note: caller must be prepared to deal with negative returns */ |
|
static inline int tcp_space(const struct sock *sk) |
|
{ |
|
return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - |
|
READ_ONCE(sk->sk_backlog.len) - |
|
atomic_read(&sk->sk_rmem_alloc)); |
|
} |
|
|
|
static inline int tcp_full_space(const struct sock *sk) |
|
{ |
|
return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf)); |
|
} |
|
|
|
void tcp_cleanup_rbuf(struct sock *sk, int copied); |
|
|
|
/* We provision sk_rcvbuf around 200% of sk_rcvlowat. |
|
* If 87.5 % (7/8) of the space has been consumed, we want to override |
|
* SO_RCVLOWAT constraint, since we are receiving skbs with too small |
|
* len/truesize ratio. |
|
*/ |
|
static inline bool tcp_rmem_pressure(const struct sock *sk) |
|
{ |
|
int rcvbuf, threshold; |
|
|
|
if (tcp_under_memory_pressure(sk)) |
|
return true; |
|
|
|
rcvbuf = READ_ONCE(sk->sk_rcvbuf); |
|
threshold = rcvbuf - (rcvbuf >> 3); |
|
|
|
return atomic_read(&sk->sk_rmem_alloc) > threshold; |
|
} |
|
|
|
static inline bool tcp_epollin_ready(const struct sock *sk, int target) |
|
{ |
|
const struct tcp_sock *tp = tcp_sk(sk); |
|
int avail = READ_ONCE(tp->rcv_nxt) - READ_ONCE(tp->copied_seq); |
|
|
|
if (avail <= 0) |
|
return false; |
|
|
|
return (avail >= target) || tcp_rmem_pressure(sk) || |
|
(tcp_receive_window(tp) <= inet_csk(sk)->icsk_ack.rcv_mss); |
|
} |
|
|
|
extern void tcp_openreq_init_rwin(struct request_sock *req, |
|
const struct sock *sk_listener, |
|
const struct dst_entry *dst); |
|
|
|
void tcp_enter_memory_pressure(struct sock *sk); |
|
void tcp_leave_memory_pressure(struct sock *sk); |
|
|
|
static inline int keepalive_intvl_when(const struct tcp_sock *tp) |
|
{ |
|
struct net *net = sock_net((struct sock *)tp); |
|
|
|
return tp->keepalive_intvl ? : net->ipv4.sysctl_tcp_keepalive_intvl; |
|
} |
|
|
|
static inline int keepalive_time_when(const struct tcp_sock *tp) |
|
{ |
|
struct net *net = sock_net((struct sock *)tp); |
|
|
|
return tp->keepalive_time ? : net->ipv4.sysctl_tcp_keepalive_time; |
|
} |
|
|
|
static inline int keepalive_probes(const struct tcp_sock *tp) |
|
{ |
|
struct net *net = sock_net((struct sock *)tp); |
|
|
|
return tp->keepalive_probes ? : net->ipv4.sysctl_tcp_keepalive_probes; |
|
} |
|
|
|
static inline u32 keepalive_time_elapsed(const struct tcp_sock *tp) |
|
{ |
|
const struct inet_connection_sock *icsk = &tp->inet_conn; |
|
|
|
return min_t(u32, tcp_jiffies32 - icsk->icsk_ack.lrcvtime, |
|
tcp_jiffies32 - tp->rcv_tstamp); |
|
} |
|
|
|
static inline int tcp_fin_time(const struct sock *sk) |
|
{ |
|
int fin_timeout = tcp_sk(sk)->linger2 ? : sock_net(sk)->ipv4.sysctl_tcp_fin_timeout; |
|
const int rto = inet_csk(sk)->icsk_rto; |
|
|
|
if (fin_timeout < (rto << 2) - (rto >> 1)) |
|
fin_timeout = (rto << 2) - (rto >> 1); |
|
|
|
return fin_timeout; |
|
} |
|
|
|
static inline bool tcp_paws_check(const struct tcp_options_received *rx_opt, |
|
int paws_win) |
|
{ |
|
if ((s32)(rx_opt->ts_recent - rx_opt->rcv_tsval) <= paws_win) |
|
return true; |
|
if (unlikely(!time_before32(ktime_get_seconds(), |
|
rx_opt->ts_recent_stamp + TCP_PAWS_24DAYS))) |
|
return true; |
|
/* |
|
* Some OSes send SYN and SYNACK messages with tsval=0 tsecr=0, |
|
* then following tcp messages have valid values. Ignore 0 value, |
|
* or else 'negative' tsval might forbid us to accept their packets. |
|
*/ |
|
if (!rx_opt->ts_recent) |
|
return true; |
|
return false; |
|
} |
|
|
|
static inline bool tcp_paws_reject(const struct tcp_options_received *rx_opt, |
|
int rst) |
|
{ |
|
if (tcp_paws_check(rx_opt, 0)) |
|
return false; |
|
|
|
/* RST segments are not recommended to carry timestamp, |
|
and, if they do, it is recommended to ignore PAWS because |
|
"their cleanup function should take precedence over timestamps." |
|
Certainly, it is mistake. It is necessary to understand the reasons |
|
of this constraint to relax it: if peer reboots, clock may go |
|
out-of-sync and half-open connections will not be reset. |
|
Actually, the problem would be not existing if all |
|
the implementations followed draft about maintaining clock |
|
via reboots. Linux-2.2 DOES NOT! |
|
|
|
However, we can relax time bounds for RST segments to MSL. |
|
*/ |
|
if (rst && !time_before32(ktime_get_seconds(), |
|
rx_opt->ts_recent_stamp + TCP_PAWS_MSL)) |
|
return false; |
|
return true; |
|
} |
|
|
|
bool tcp_oow_rate_limited(struct net *net, const struct sk_buff *skb, |
|
int mib_idx, u32 *last_oow_ack_time); |
|
|
|
static inline void tcp_mib_init(struct net *net) |
|
{ |
|
/* See RFC 2012 */ |
|
TCP_ADD_STATS(net, TCP_MIB_RTOALGORITHM, 1); |
|
TCP_ADD_STATS(net, TCP_MIB_RTOMIN, TCP_RTO_MIN*1000/HZ); |
|
TCP_ADD_STATS(net, TCP_MIB_RTOMAX, TCP_RTO_MAX*1000/HZ); |
|
TCP_ADD_STATS(net, TCP_MIB_MAXCONN, -1); |
|
} |
|
|
|
/* from STCP */ |
|
static inline void tcp_clear_retrans_hints_partial(struct tcp_sock *tp) |
|
{ |
|
tp->lost_skb_hint = NULL; |
|
} |
|
|
|
static inline void tcp_clear_all_retrans_hints(struct tcp_sock *tp) |
|
{ |
|
tcp_clear_retrans_hints_partial(tp); |
|
tp->retransmit_skb_hint = NULL; |
|
} |
|
|
|
union tcp_md5_addr { |
|
struct in_addr a4; |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
struct in6_addr a6; |
|
#endif |
|
}; |
|
|
|
/* - key database */ |
|
struct tcp_md5sig_key { |
|
struct hlist_node node; |
|
u8 keylen; |
|
u8 family; /* AF_INET or AF_INET6 */ |
|
u8 prefixlen; |
|
union tcp_md5_addr addr; |
|
int l3index; /* set if key added with L3 scope */ |
|
u8 key[TCP_MD5SIG_MAXKEYLEN]; |
|
struct rcu_head rcu; |
|
}; |
|
|
|
/* - sock block */ |
|
struct tcp_md5sig_info { |
|
struct hlist_head head; |
|
struct rcu_head rcu; |
|
}; |
|
|
|
/* - pseudo header */ |
|
struct tcp4_pseudohdr { |
|
__be32 saddr; |
|
__be32 daddr; |
|
__u8 pad; |
|
__u8 protocol; |
|
__be16 len; |
|
}; |
|
|
|
struct tcp6_pseudohdr { |
|
struct in6_addr saddr; |
|
struct in6_addr daddr; |
|
__be32 len; |
|
__be32 protocol; /* including padding */ |
|
}; |
|
|
|
union tcp_md5sum_block { |
|
struct tcp4_pseudohdr ip4; |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
struct tcp6_pseudohdr ip6; |
|
#endif |
|
}; |
|
|
|
/* - pool: digest algorithm, hash description and scratch buffer */ |
|
struct tcp_md5sig_pool { |
|
struct ahash_request *md5_req; |
|
void *scratch; |
|
}; |
|
|
|
/* - functions */ |
|
int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, |
|
const struct sock *sk, const struct sk_buff *skb); |
|
int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, |
|
int family, u8 prefixlen, int l3index, |
|
const u8 *newkey, u8 newkeylen, gfp_t gfp); |
|
int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, |
|
int family, u8 prefixlen, int l3index); |
|
struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, |
|
const struct sock *addr_sk); |
|
|
|
#ifdef CONFIG_TCP_MD5SIG |
|
#include <linux/jump_label.h> |
|
extern struct static_key_false tcp_md5_needed; |
|
struct tcp_md5sig_key *__tcp_md5_do_lookup(const struct sock *sk, int l3index, |
|
const union tcp_md5_addr *addr, |
|
int family); |
|
static inline struct tcp_md5sig_key * |
|
tcp_md5_do_lookup(const struct sock *sk, int l3index, |
|
const union tcp_md5_addr *addr, int family) |
|
{ |
|
if (!static_branch_unlikely(&tcp_md5_needed)) |
|
return NULL; |
|
return __tcp_md5_do_lookup(sk, l3index, addr, family); |
|
} |
|
|
|
#define tcp_twsk_md5_key(twsk) ((twsk)->tw_md5_key) |
|
#else |
|
static inline struct tcp_md5sig_key * |
|
tcp_md5_do_lookup(const struct sock *sk, int l3index, |
|
const union tcp_md5_addr *addr, int family) |
|
{ |
|
return NULL; |
|
} |
|
#define tcp_twsk_md5_key(twsk) NULL |
|
#endif |
|
|
|
bool tcp_alloc_md5sig_pool(void); |
|
|
|
struct tcp_md5sig_pool *tcp_get_md5sig_pool(void); |
|
static inline void tcp_put_md5sig_pool(void) |
|
{ |
|
local_bh_enable(); |
|
} |
|
|
|
int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *, const struct sk_buff *, |
|
unsigned int header_len); |
|
int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, |
|
const struct tcp_md5sig_key *key); |
|
|
|
/* From tcp_fastopen.c */ |
|
void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, |
|
struct tcp_fastopen_cookie *cookie); |
|
void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
|
struct tcp_fastopen_cookie *cookie, bool syn_lost, |
|
u16 try_exp); |
|
struct tcp_fastopen_request { |
|
/* Fast Open cookie. Size 0 means a cookie request */ |
|
struct tcp_fastopen_cookie cookie; |
|
struct msghdr *data; /* data in MSG_FASTOPEN */ |
|
size_t size; |
|
int copied; /* queued in tcp_connect() */ |
|
struct ubuf_info *uarg; |
|
}; |
|
void tcp_free_fastopen_req(struct tcp_sock *tp); |
|
void tcp_fastopen_destroy_cipher(struct sock *sk); |
|
void tcp_fastopen_ctx_destroy(struct net *net); |
|
int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk, |
|
void *primary_key, void *backup_key); |
|
int tcp_fastopen_get_cipher(struct net *net, struct inet_connection_sock *icsk, |
|
u64 *key); |
|
void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb); |
|
struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb, |
|
struct request_sock *req, |
|
struct tcp_fastopen_cookie *foc, |
|
const struct dst_entry *dst); |
|
void tcp_fastopen_init_key_once(struct net *net); |
|
bool tcp_fastopen_cookie_check(struct sock *sk, u16 *mss, |
|
struct tcp_fastopen_cookie *cookie); |
|
bool tcp_fastopen_defer_connect(struct sock *sk, int *err); |
|
#define TCP_FASTOPEN_KEY_LENGTH sizeof(siphash_key_t) |
|
#define TCP_FASTOPEN_KEY_MAX 2 |
|
#define TCP_FASTOPEN_KEY_BUF_LENGTH \ |
|
(TCP_FASTOPEN_KEY_LENGTH * TCP_FASTOPEN_KEY_MAX) |
|
|
|
/* Fastopen key context */ |
|
struct tcp_fastopen_context { |
|
siphash_key_t key[TCP_FASTOPEN_KEY_MAX]; |
|
int num; |
|
struct rcu_head rcu; |
|
}; |
|
|
|
extern unsigned int sysctl_tcp_fastopen_blackhole_timeout; |
|
void tcp_fastopen_active_disable(struct sock *sk); |
|
bool tcp_fastopen_active_should_disable(struct sock *sk); |
|
void tcp_fastopen_active_disable_ofo_check(struct sock *sk); |
|
void tcp_fastopen_active_detect_blackhole(struct sock *sk, bool expired); |
|
|
|
/* Caller needs to wrap with rcu_read_(un)lock() */ |
|
static inline |
|
struct tcp_fastopen_context *tcp_fastopen_get_ctx(const struct sock *sk) |
|
{ |
|
struct tcp_fastopen_context *ctx; |
|
|
|
ctx = rcu_dereference(inet_csk(sk)->icsk_accept_queue.fastopenq.ctx); |
|
if (!ctx) |
|
ctx = rcu_dereference(sock_net(sk)->ipv4.tcp_fastopen_ctx); |
|
return ctx; |
|
} |
|
|
|
static inline |
|
bool tcp_fastopen_cookie_match(const struct tcp_fastopen_cookie *foc, |
|
const struct tcp_fastopen_cookie *orig) |
|
{ |
|
if (orig->len == TCP_FASTOPEN_COOKIE_SIZE && |
|
orig->len == foc->len && |
|
!memcmp(orig->val, foc->val, foc->len)) |
|
return true; |
|
return false; |
|
} |
|
|
|
static inline |
|
int tcp_fastopen_context_len(const struct tcp_fastopen_context *ctx) |
|
{ |
|
return ctx->num; |
|
} |
|
|
|
/* Latencies incurred by various limits for a sender. They are |
|
* chronograph-like stats that are mutually exclusive. |
|
*/ |
|
enum tcp_chrono { |
|
TCP_CHRONO_UNSPEC, |
|
TCP_CHRONO_BUSY, /* Actively sending data (non-empty write queue) */ |
|
TCP_CHRONO_RWND_LIMITED, /* Stalled by insufficient receive window */ |
|
TCP_CHRONO_SNDBUF_LIMITED, /* Stalled by insufficient send buffer */ |
|
__TCP_CHRONO_MAX, |
|
}; |
|
|
|
void tcp_chrono_start(struct sock *sk, const enum tcp_chrono type); |
|
void tcp_chrono_stop(struct sock *sk, const enum tcp_chrono type); |
|
|
|
/* This helper is needed, because skb->tcp_tsorted_anchor uses |
|
* the same memory storage than skb->destructor/_skb_refdst |
|
*/ |
|
static inline void tcp_skb_tsorted_anchor_cleanup(struct sk_buff *skb) |
|
{ |
|
skb->destructor = NULL; |
|
skb->_skb_refdst = 0UL; |
|
} |
|
|
|
#define tcp_skb_tsorted_save(skb) { \ |
|
unsigned long _save = skb->_skb_refdst; \ |
|
skb->_skb_refdst = 0UL; |
|
|
|
#define tcp_skb_tsorted_restore(skb) \ |
|
skb->_skb_refdst = _save; \ |
|
} |
|
|
|
void tcp_write_queue_purge(struct sock *sk); |
|
|
|
static inline struct sk_buff *tcp_rtx_queue_head(const struct sock *sk) |
|
{ |
|
return skb_rb_first(&sk->tcp_rtx_queue); |
|
} |
|
|
|
static inline struct sk_buff *tcp_rtx_queue_tail(const struct sock *sk) |
|
{ |
|
return skb_rb_last(&sk->tcp_rtx_queue); |
|
} |
|
|
|
static inline struct sk_buff *tcp_write_queue_head(const struct sock *sk) |
|
{ |
|
return skb_peek(&sk->sk_write_queue); |
|
} |
|
|
|
static inline struct sk_buff *tcp_write_queue_tail(const struct sock *sk) |
|
{ |
|
return skb_peek_tail(&sk->sk_write_queue); |
|
} |
|
|
|
#define tcp_for_write_queue_from_safe(skb, tmp, sk) \ |
|
skb_queue_walk_from_safe(&(sk)->sk_write_queue, skb, tmp) |
|
|
|
static inline struct sk_buff *tcp_send_head(const struct sock *sk) |
|
{ |
|
return skb_peek(&sk->sk_write_queue); |
|
} |
|
|
|
static inline bool tcp_skb_is_last(const struct sock *sk, |
|
const struct sk_buff *skb) |
|
{ |
|
return skb_queue_is_last(&sk->sk_write_queue, skb); |
|
} |
|
|
|
/** |
|
* tcp_write_queue_empty - test if any payload (or FIN) is available in write queue |
|
* @sk: socket |
|
* |
|
* Since the write queue can have a temporary empty skb in it, |
|
* we must not use "return skb_queue_empty(&sk->sk_write_queue)" |
|
*/ |
|
static inline bool tcp_write_queue_empty(const struct sock *sk) |
|
{ |
|
const struct tcp_sock *tp = tcp_sk(sk); |
|
|
|
return tp->write_seq == tp->snd_nxt; |
|
} |
|
|
|
static inline bool tcp_rtx_queue_empty(const struct sock *sk) |
|
{ |
|
return RB_EMPTY_ROOT(&sk->tcp_rtx_queue); |
|
} |
|
|
|
static inline bool tcp_rtx_and_write_queues_empty(const struct sock *sk) |
|
{ |
|
return tcp_rtx_queue_empty(sk) && tcp_write_queue_empty(sk); |
|
} |
|
|
|
static inline void tcp_add_write_queue_tail(struct sock *sk, struct sk_buff *skb) |
|
{ |
|
__skb_queue_tail(&sk->sk_write_queue, skb); |
|
|
|
/* Queue it, remembering where we must start sending. */ |
|
if (sk->sk_write_queue.next == skb) |
|
tcp_chrono_start(sk, TCP_CHRONO_BUSY); |
|
} |
|
|
|
/* Insert new before skb on the write queue of sk. */ |
|
static inline void tcp_insert_write_queue_before(struct sk_buff *new, |
|
struct sk_buff *skb, |
|
struct sock *sk) |
|
{ |
|
__skb_queue_before(&sk->sk_write_queue, skb, new); |
|
} |
|
|
|
static inline void tcp_unlink_write_queue(struct sk_buff *skb, struct sock *sk) |
|
{ |
|
tcp_skb_tsorted_anchor_cleanup(skb); |
|
__skb_unlink(skb, &sk->sk_write_queue); |
|
} |
|
|
|
void tcp_rbtree_insert(struct rb_root *root, struct sk_buff *skb); |
|
|
|
static inline void tcp_rtx_queue_unlink(struct sk_buff *skb, struct sock *sk) |
|
{ |
|
tcp_skb_tsorted_anchor_cleanup(skb); |
|
rb_erase(&skb->rbnode, &sk->tcp_rtx_queue); |
|
} |
|
|
|
static inline void tcp_rtx_queue_unlink_and_free(struct sk_buff *skb, struct sock *sk) |
|
{ |
|
list_del(&skb->tcp_tsorted_anchor); |
|
tcp_rtx_queue_unlink(skb, sk); |
|
sk_wmem_free_skb(sk, skb); |
|
} |
|
|
|
static inline void tcp_push_pending_frames(struct sock *sk) |
|
{ |
|
if (tcp_send_head(sk)) { |
|
struct tcp_sock *tp = tcp_sk(sk); |
|
|
|
__tcp_push_pending_frames(sk, tcp_current_mss(sk), tp->nonagle); |
|
} |
|
} |
|
|
|
/* Start sequence of the skb just after the highest skb with SACKed |
|
* bit, valid only if sacked_out > 0 or when the caller has ensured |
|
* validity by itself. |
|
*/ |
|
static inline u32 tcp_highest_sack_seq(struct tcp_sock *tp) |
|
{ |
|
if (!tp->sacked_out) |
|
return tp->snd_una; |
|
|
|
if (tp->highest_sack == NULL) |
|
return tp->snd_nxt; |
|
|
|
return TCP_SKB_CB(tp->highest_sack)->seq; |
|
} |
|
|
|
static inline void tcp_advance_highest_sack(struct sock *sk, struct sk_buff *skb) |
|
{ |
|
tcp_sk(sk)->highest_sack = skb_rb_next(skb); |
|
} |
|
|
|
static inline struct sk_buff *tcp_highest_sack(struct sock *sk) |
|
{ |
|
return tcp_sk(sk)->highest_sack; |
|
} |
|
|
|
static inline void tcp_highest_sack_reset(struct sock *sk) |
|
{ |
|
tcp_sk(sk)->highest_sack = tcp_rtx_queue_head(sk); |
|
} |
|
|
|
/* Called when old skb is about to be deleted and replaced by new skb */ |
|
static inline void tcp_highest_sack_replace(struct sock *sk, |
|
struct sk_buff *old, |
|
struct sk_buff *new) |
|
{ |
|
if (old == tcp_highest_sack(sk)) |
|
tcp_sk(sk)->highest_sack = new; |
|
} |
|
|
|
/* This helper checks if socket has IP_TRANSPARENT set */ |
|
static inline bool inet_sk_transparent(const struct sock *sk) |
|
{ |
|
switch (sk->sk_state) { |
|
case TCP_TIME_WAIT: |
|
return inet_twsk(sk)->tw_transparent; |
|
case TCP_NEW_SYN_RECV: |
|
return inet_rsk(inet_reqsk(sk))->no_srccheck; |
|
} |
|
return inet_sk(sk)->transparent; |
|
} |
|
|
|
/* Determines whether this is a thin stream (which may suffer from |
|
* increased latency). Used to trigger latency-reducing mechanisms. |
|
*/ |
|
static inline bool tcp_stream_is_thin(struct tcp_sock *tp) |
|
{ |
|
return tp->packets_out < 4 && !tcp_in_initial_slowstart(tp); |
|
} |
|
|
|
/* /proc */ |
|
enum tcp_seq_states { |
|
TCP_SEQ_STATE_LISTENING, |
|
TCP_SEQ_STATE_ESTABLISHED, |
|
}; |
|
|
|
void *tcp_seq_start(struct seq_file *seq, loff_t *pos); |
|
void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos); |
|
void tcp_seq_stop(struct seq_file *seq, void *v); |
|
|
|
struct tcp_seq_afinfo { |
|
sa_family_t family; |
|
}; |
|
|
|
struct tcp_iter_state { |
|
struct seq_net_private p; |
|
enum tcp_seq_states state; |
|
struct sock *syn_wait_sk; |
|
struct tcp_seq_afinfo *bpf_seq_afinfo; |
|
int bucket, offset, sbucket, num; |
|
loff_t last_pos; |
|
}; |
|
|
|
extern struct request_sock_ops tcp_request_sock_ops; |
|
extern struct request_sock_ops tcp6_request_sock_ops; |
|
|
|
void tcp_v4_destroy_sock(struct sock *sk); |
|
|
|
struct sk_buff *tcp_gso_segment(struct sk_buff *skb, |
|
netdev_features_t features); |
|
struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb); |
|
INDIRECT_CALLABLE_DECLARE(int tcp4_gro_complete(struct sk_buff *skb, int thoff)); |
|
INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp4_gro_receive(struct list_head *head, struct sk_buff *skb)); |
|
INDIRECT_CALLABLE_DECLARE(int tcp6_gro_complete(struct sk_buff *skb, int thoff)); |
|
INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp6_gro_receive(struct list_head *head, struct sk_buff *skb)); |
|
int tcp_gro_complete(struct sk_buff *skb); |
|
|
|
void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr); |
|
|
|
static inline u32 tcp_notsent_lowat(const struct tcp_sock *tp) |
|
{ |
|
struct net *net = sock_net((struct sock *)tp); |
|
return tp->notsent_lowat ?: net->ipv4.sysctl_tcp_notsent_lowat; |
|
} |
|
|
|
bool tcp_stream_memory_free(const struct sock *sk, int wake); |
|
|
|
#ifdef CONFIG_PROC_FS |
|
int tcp4_proc_init(void); |
|
void tcp4_proc_exit(void); |
|
#endif |
|
|
|
int tcp_rtx_synack(const struct sock *sk, struct request_sock *req); |
|
int tcp_conn_request(struct request_sock_ops *rsk_ops, |
|
const struct tcp_request_sock_ops *af_ops, |
|
struct sock *sk, struct sk_buff *skb); |
|
|
|
/* TCP af-specific functions */ |
|
struct tcp_sock_af_ops { |
|
#ifdef CONFIG_TCP_MD5SIG |
|
struct tcp_md5sig_key *(*md5_lookup) (const struct sock *sk, |
|
const struct sock *addr_sk); |
|
int (*calc_md5_hash)(char *location, |
|
const struct tcp_md5sig_key *md5, |
|
const struct sock *sk, |
|
const struct sk_buff *skb); |
|
int (*md5_parse)(struct sock *sk, |
|
int optname, |
|
sockptr_t optval, |
|
int optlen); |
|
#endif |
|
}; |
|
|
|
struct tcp_request_sock_ops { |
|
u16 mss_clamp; |
|
#ifdef CONFIG_TCP_MD5SIG |
|
struct tcp_md5sig_key *(*req_md5_lookup)(const struct sock *sk, |
|
const struct sock *addr_sk); |
|
int (*calc_md5_hash) (char *location, |
|
const struct tcp_md5sig_key *md5, |
|
const struct sock *sk, |
|
const struct sk_buff *skb); |
|
#endif |
|
#ifdef CONFIG_SYN_COOKIES |
|
__u32 (*cookie_init_seq)(const struct sk_buff *skb, |
|
__u16 *mss); |
|
#endif |
|
struct dst_entry *(*route_req)(const struct sock *sk, |
|
struct sk_buff *skb, |
|
struct flowi *fl, |
|
struct request_sock *req); |
|
u32 (*init_seq)(const struct sk_buff *skb); |
|
u32 (*init_ts_off)(const struct net *net, const struct sk_buff *skb); |
|
int (*send_synack)(const struct sock *sk, struct dst_entry *dst, |
|
struct flowi *fl, struct request_sock *req, |
|
struct tcp_fastopen_cookie *foc, |
|
enum tcp_synack_type synack_type, |
|
struct sk_buff *syn_skb); |
|
}; |
|
|
|
extern const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops; |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
extern const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops; |
|
#endif |
|
|
|
#ifdef CONFIG_SYN_COOKIES |
|
static inline __u32 cookie_init_sequence(const struct tcp_request_sock_ops *ops, |
|
const struct sock *sk, struct sk_buff *skb, |
|
__u16 *mss) |
|
{ |
|
tcp_synq_overflow(sk); |
|
__NET_INC_STATS(sock_net(sk), LINUX_MIB_SYNCOOKIESSENT); |
|
return ops->cookie_init_seq(skb, mss); |
|
} |
|
#else |
|
static inline __u32 cookie_init_sequence(const struct tcp_request_sock_ops *ops, |
|
const struct sock *sk, struct sk_buff *skb, |
|
__u16 *mss) |
|
{ |
|
return 0; |
|
} |
|
#endif |
|
|
|
int tcpv4_offload_init(void); |
|
|
|
void tcp_v4_init(void); |
|
void tcp_init(void); |
|
|
|
/* tcp_recovery.c */ |
|
void tcp_mark_skb_lost(struct sock *sk, struct sk_buff *skb); |
|
void tcp_newreno_mark_lost(struct sock *sk, bool snd_una_advanced); |
|
extern s32 tcp_rack_skb_timeout(struct tcp_sock *tp, struct sk_buff *skb, |
|
u32 reo_wnd); |
|
extern bool tcp_rack_mark_lost(struct sock *sk); |
|
extern void tcp_rack_advance(struct tcp_sock *tp, u8 sacked, u32 end_seq, |
|
u64 xmit_time); |
|
extern void tcp_rack_reo_timeout(struct sock *sk); |
|
extern void tcp_rack_update_reo_wnd(struct sock *sk, struct rate_sample *rs); |
|
|
|
/* At how many usecs into the future should the RTO fire? */ |
|
static inline s64 tcp_rto_delta_us(const struct sock *sk) |
|
{ |
|
const struct sk_buff *skb = tcp_rtx_queue_head(sk); |
|
u32 rto = inet_csk(sk)->icsk_rto; |
|
u64 rto_time_stamp_us = tcp_skb_timestamp_us(skb) + jiffies_to_usecs(rto); |
|
|
|
return rto_time_stamp_us - tcp_sk(sk)->tcp_mstamp; |
|
} |
|
|
|
/* |
|
* Save and compile IPv4 options, return a pointer to it |
|
*/ |
|
static inline struct ip_options_rcu *tcp_v4_save_options(struct net *net, |
|
struct sk_buff *skb) |
|
{ |
|
const struct ip_options *opt = &TCP_SKB_CB(skb)->header.h4.opt; |
|
struct ip_options_rcu *dopt = NULL; |
|
|
|
if (opt->optlen) { |
|
int opt_size = sizeof(*dopt) + opt->optlen; |
|
|
|
dopt = kmalloc(opt_size, GFP_ATOMIC); |
|
if (dopt && __ip_options_echo(net, &dopt->opt, skb, opt)) { |
|
kfree(dopt); |
|
dopt = NULL; |
|
} |
|
} |
|
return dopt; |
|
} |
|
|
|
/* locally generated TCP pure ACKs have skb->truesize == 2 |
|
* (check tcp_send_ack() in net/ipv4/tcp_output.c ) |
|
* This is much faster than dissecting the packet to find out. |
|
* (Think of GRE encapsulations, IPv4, IPv6, ...) |
|
*/ |
|
static inline bool skb_is_tcp_pure_ack(const struct sk_buff *skb) |
|
{ |
|
return skb->truesize == 2; |
|
} |
|
|
|
static inline void skb_set_tcp_pure_ack(struct sk_buff *skb) |
|
{ |
|
skb->truesize = 2; |
|
} |
|
|
|
static inline int tcp_inq(struct sock *sk) |
|
{ |
|
struct tcp_sock *tp = tcp_sk(sk); |
|
int answ; |
|
|
|
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) { |
|
answ = 0; |
|
} else if (sock_flag(sk, SOCK_URGINLINE) || |
|
!tp->urg_data || |
|
before(tp->urg_seq, tp->copied_seq) || |
|
!before(tp->urg_seq, tp->rcv_nxt)) { |
|
|
|
answ = tp->rcv_nxt - tp->copied_seq; |
|
|
|
/* Subtract 1, if FIN was received */ |
|
if (answ && sock_flag(sk, SOCK_DONE)) |
|
answ--; |
|
} else { |
|
answ = tp->urg_seq - tp->copied_seq; |
|
} |
|
|
|
return answ; |
|
} |
|
|
|
int tcp_peek_len(struct socket *sock); |
|
|
|
static inline void tcp_segs_in(struct tcp_sock *tp, const struct sk_buff *skb) |
|
{ |
|
u16 segs_in; |
|
|
|
segs_in = max_t(u16, 1, skb_shinfo(skb)->gso_segs); |
|
tp->segs_in += segs_in; |
|
if (skb->len > tcp_hdrlen(skb)) |
|
tp->data_segs_in += segs_in; |
|
} |
|
|
|
/* |
|
* TCP listen path runs lockless. |
|
* We forced "struct sock" to be const qualified to make sure |
|
* we don't modify one of its field by mistake. |
|
* Here, we increment sk_drops which is an atomic_t, so we can safely |
|
* make sock writable again. |
|
*/ |
|
static inline void tcp_listendrop(const struct sock *sk) |
|
{ |
|
atomic_inc(&((struct sock *)sk)->sk_drops); |
|
__NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS); |
|
} |
|
|
|
enum hrtimer_restart tcp_pace_kick(struct hrtimer *timer); |
|
|
|
/* |
|
* Interface for adding Upper Level Protocols over TCP |
|
*/ |
|
|
|
#define TCP_ULP_NAME_MAX 16 |
|
#define TCP_ULP_MAX 128 |
|
#define TCP_ULP_BUF_MAX (TCP_ULP_NAME_MAX*TCP_ULP_MAX) |
|
|
|
struct tcp_ulp_ops { |
|
struct list_head list; |
|
|
|
/* initialize ulp */ |
|
int (*init)(struct sock *sk); |
|
/* update ulp */ |
|
void (*update)(struct sock *sk, struct proto *p, |
|
void (*write_space)(struct sock *sk)); |
|
/* cleanup ulp */ |
|
void (*release)(struct sock *sk); |
|
/* diagnostic */ |
|
int (*get_info)(const struct sock *sk, struct sk_buff *skb); |
|
size_t (*get_info_size)(const struct sock *sk); |
|
/* clone ulp */ |
|
void (*clone)(const struct request_sock *req, struct sock *newsk, |
|
const gfp_t priority); |
|
|
|
char name[TCP_ULP_NAME_MAX]; |
|
struct module *owner; |
|
}; |
|
int tcp_register_ulp(struct tcp_ulp_ops *type); |
|
void tcp_unregister_ulp(struct tcp_ulp_ops *type); |
|
int tcp_set_ulp(struct sock *sk, const char *name); |
|
void tcp_get_available_ulp(char *buf, size_t len); |
|
void tcp_cleanup_ulp(struct sock *sk); |
|
void tcp_update_ulp(struct sock *sk, struct proto *p, |
|
void (*write_space)(struct sock *sk)); |
|
|
|
#define MODULE_ALIAS_TCP_ULP(name) \ |
|
__MODULE_INFO(alias, alias_userspace, name); \ |
|
__MODULE_INFO(alias, alias_tcp_ulp, "tcp-ulp-" name) |
|
|
|
struct sk_msg; |
|
struct sk_psock; |
|
|
|
#ifdef CONFIG_BPF_STREAM_PARSER |
|
struct proto *tcp_bpf_get_proto(struct sock *sk, struct sk_psock *psock); |
|
void tcp_bpf_clone(const struct sock *sk, struct sock *newsk); |
|
#else |
|
static inline void tcp_bpf_clone(const struct sock *sk, struct sock *newsk) |
|
{ |
|
} |
|
#endif /* CONFIG_BPF_STREAM_PARSER */ |
|
|
|
#ifdef CONFIG_NET_SOCK_MSG |
|
int tcp_bpf_sendmsg_redir(struct sock *sk, struct sk_msg *msg, u32 bytes, |
|
int flags); |
|
int __tcp_bpf_recvmsg(struct sock *sk, struct sk_psock *psock, |
|
struct msghdr *msg, int len, int flags); |
|
#endif /* CONFIG_NET_SOCK_MSG */ |
|
|
|
#ifdef CONFIG_CGROUP_BPF |
|
static inline void bpf_skops_init_skb(struct bpf_sock_ops_kern *skops, |
|
struct sk_buff *skb, |
|
unsigned int end_offset) |
|
{ |
|
skops->skb = skb; |
|
skops->skb_data_end = skb->data + end_offset; |
|
} |
|
#else |
|
static inline void bpf_skops_init_skb(struct bpf_sock_ops_kern *skops, |
|
struct sk_buff *skb, |
|
unsigned int end_offset) |
|
{ |
|
} |
|
#endif |
|
|
|
/* Call BPF_SOCK_OPS program that returns an int. If the return value |
|
* is < 0, then the BPF op failed (for example if the loaded BPF |
|
* program does not support the chosen operation or there is no BPF |
|
* program loaded). |
|
*/ |
|
#ifdef CONFIG_BPF |
|
static inline int tcp_call_bpf(struct sock *sk, int op, u32 nargs, u32 *args) |
|
{ |
|
struct bpf_sock_ops_kern sock_ops; |
|
int ret; |
|
|
|
memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp)); |
|
if (sk_fullsock(sk)) { |
|
sock_ops.is_fullsock = 1; |
|
sock_owned_by_me(sk); |
|
} |
|
|
|
sock_ops.sk = sk; |
|
sock_ops.op = op; |
|
if (nargs > 0) |
|
memcpy(sock_ops.args, args, nargs * sizeof(*args)); |
|
|
|
ret = BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops); |
|
if (ret == 0) |
|
ret = sock_ops.reply; |
|
else |
|
ret = -1; |
|
return ret; |
|
} |
|
|
|
static inline int tcp_call_bpf_2arg(struct sock *sk, int op, u32 arg1, u32 arg2) |
|
{ |
|
u32 args[2] = {arg1, arg2}; |
|
|
|
return tcp_call_bpf(sk, op, 2, args); |
|
} |
|
|
|
static inline int tcp_call_bpf_3arg(struct sock *sk, int op, u32 arg1, u32 arg2, |
|
u32 arg3) |
|
{ |
|
u32 args[3] = {arg1, arg2, arg3}; |
|
|
|
return tcp_call_bpf(sk, op, 3, args); |
|
} |
|
|
|
#else |
|
static inline int tcp_call_bpf(struct sock *sk, int op, u32 nargs, u32 *args) |
|
{ |
|
return -EPERM; |
|
} |
|
|
|
static inline int tcp_call_bpf_2arg(struct sock *sk, int op, u32 arg1, u32 arg2) |
|
{ |
|
return -EPERM; |
|
} |
|
|
|
static inline int tcp_call_bpf_3arg(struct sock *sk, int op, u32 arg1, u32 arg2, |
|
u32 arg3) |
|
{ |
|
return -EPERM; |
|
} |
|
|
|
#endif |
|
|
|
static inline u32 tcp_timeout_init(struct sock *sk) |
|
{ |
|
int timeout; |
|
|
|
timeout = tcp_call_bpf(sk, BPF_SOCK_OPS_TIMEOUT_INIT, 0, NULL); |
|
|
|
if (timeout <= 0) |
|
timeout = TCP_TIMEOUT_INIT; |
|
return timeout; |
|
} |
|
|
|
static inline u32 tcp_rwnd_init_bpf(struct sock *sk) |
|
{ |
|
int rwnd; |
|
|
|
rwnd = tcp_call_bpf(sk, BPF_SOCK_OPS_RWND_INIT, 0, NULL); |
|
|
|
if (rwnd < 0) |
|
rwnd = 0; |
|
return rwnd; |
|
} |
|
|
|
static inline bool tcp_bpf_ca_needs_ecn(struct sock *sk) |
|
{ |
|
return (tcp_call_bpf(sk, BPF_SOCK_OPS_NEEDS_ECN, 0, NULL) == 1); |
|
} |
|
|
|
static inline void tcp_bpf_rtt(struct sock *sk) |
|
{ |
|
if (BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_RTT_CB_FLAG)) |
|
tcp_call_bpf(sk, BPF_SOCK_OPS_RTT_CB, 0, NULL); |
|
} |
|
|
|
#if IS_ENABLED(CONFIG_SMC) |
|
extern struct static_key_false tcp_have_smc; |
|
#endif |
|
|
|
#if IS_ENABLED(CONFIG_TLS_DEVICE) |
|
void clean_acked_data_enable(struct inet_connection_sock *icsk, |
|
void (*cad)(struct sock *sk, u32 ack_seq)); |
|
void clean_acked_data_disable(struct inet_connection_sock *icsk); |
|
void clean_acked_data_flush(void); |
|
#endif |
|
|
|
DECLARE_STATIC_KEY_FALSE(tcp_tx_delay_enabled); |
|
static inline void tcp_add_tx_delay(struct sk_buff *skb, |
|
const struct tcp_sock *tp) |
|
{ |
|
if (static_branch_unlikely(&tcp_tx_delay_enabled)) |
|
skb->skb_mstamp_ns += (u64)tp->tcp_tx_delay * NSEC_PER_USEC; |
|
} |
|
|
|
/* Compute Earliest Departure Time for some control packets |
|
* like ACK or RST for TIME_WAIT or non ESTABLISHED sockets. |
|
*/ |
|
static inline u64 tcp_transmit_time(const struct sock *sk) |
|
{ |
|
if (static_branch_unlikely(&tcp_tx_delay_enabled)) { |
|
u32 delay = (sk->sk_state == TCP_TIME_WAIT) ? |
|
tcp_twsk(sk)->tw_tx_delay : tcp_sk(sk)->tcp_tx_delay; |
|
|
|
return tcp_clock_ns() + (u64)delay * NSEC_PER_USEC; |
|
} |
|
return 0; |
|
} |
|
|
|
#endif /* _TCP_H */
|
|
|