mirror of https://gitee.com/openkylin/linux.git
3484 lines
89 KiB
C
3484 lines
89 KiB
C
/*
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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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* Implementation of the Transmission Control Protocol(TCP).
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*
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* Authors: Ross Biro
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* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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* Mark Evans, <evansmp@uhura.aston.ac.uk>
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* Corey Minyard <wf-rch!minyard@relay.EU.net>
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* Florian La Roche, <flla@stud.uni-sb.de>
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* Charles Hedrick, <hedrick@klinzhai.rutgers.edu>
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* Linus Torvalds, <torvalds@cs.helsinki.fi>
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* Alan Cox, <gw4pts@gw4pts.ampr.org>
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* Matthew Dillon, <dillon@apollo.west.oic.com>
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* Arnt Gulbrandsen, <agulbra@nvg.unit.no>
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* Jorge Cwik, <jorge@laser.satlink.net>
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*
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* Fixes:
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* Alan Cox : Numerous verify_area() calls
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* Alan Cox : Set the ACK bit on a reset
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* Alan Cox : Stopped it crashing if it closed while
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* sk->inuse=1 and was trying to connect
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* (tcp_err()).
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* Alan Cox : All icmp error handling was broken
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* pointers passed where wrong and the
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* socket was looked up backwards. Nobody
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* tested any icmp error code obviously.
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* Alan Cox : tcp_err() now handled properly. It
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* wakes people on errors. poll
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* behaves and the icmp error race
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* has gone by moving it into sock.c
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* Alan Cox : tcp_send_reset() fixed to work for
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* everything not just packets for
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* unknown sockets.
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* Alan Cox : tcp option processing.
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* Alan Cox : Reset tweaked (still not 100%) [Had
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* syn rule wrong]
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* Herp Rosmanith : More reset fixes
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* Alan Cox : No longer acks invalid rst frames.
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* Acking any kind of RST is right out.
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* Alan Cox : Sets an ignore me flag on an rst
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* receive otherwise odd bits of prattle
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* escape still
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* Alan Cox : Fixed another acking RST frame bug.
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* Should stop LAN workplace lockups.
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* Alan Cox : Some tidyups using the new skb list
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* facilities
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* Alan Cox : sk->keepopen now seems to work
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* Alan Cox : Pulls options out correctly on accepts
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* Alan Cox : Fixed assorted sk->rqueue->next errors
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* Alan Cox : PSH doesn't end a TCP read. Switched a
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* bit to skb ops.
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* Alan Cox : Tidied tcp_data to avoid a potential
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* nasty.
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* Alan Cox : Added some better commenting, as the
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* tcp is hard to follow
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* Alan Cox : Removed incorrect check for 20 * psh
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* Michael O'Reilly : ack < copied bug fix.
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* Johannes Stille : Misc tcp fixes (not all in yet).
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* Alan Cox : FIN with no memory -> CRASH
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* Alan Cox : Added socket option proto entries.
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* Also added awareness of them to accept.
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* Alan Cox : Added TCP options (SOL_TCP)
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* Alan Cox : Switched wakeup calls to callbacks,
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* so the kernel can layer network
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* sockets.
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* Alan Cox : Use ip_tos/ip_ttl settings.
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* Alan Cox : Handle FIN (more) properly (we hope).
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* Alan Cox : RST frames sent on unsynchronised
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* state ack error.
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* Alan Cox : Put in missing check for SYN bit.
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* Alan Cox : Added tcp_select_window() aka NET2E
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* window non shrink trick.
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* Alan Cox : Added a couple of small NET2E timer
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* fixes
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* Charles Hedrick : TCP fixes
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* Toomas Tamm : TCP window fixes
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* Alan Cox : Small URG fix to rlogin ^C ack fight
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* Charles Hedrick : Rewrote most of it to actually work
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* Linus : Rewrote tcp_read() and URG handling
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* completely
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* Gerhard Koerting: Fixed some missing timer handling
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* Matthew Dillon : Reworked TCP machine states as per RFC
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* Gerhard Koerting: PC/TCP workarounds
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* Adam Caldwell : Assorted timer/timing errors
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* Matthew Dillon : Fixed another RST bug
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* Alan Cox : Move to kernel side addressing changes.
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* Alan Cox : Beginning work on TCP fastpathing
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* (not yet usable)
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* Arnt Gulbrandsen: Turbocharged tcp_check() routine.
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* Alan Cox : TCP fast path debugging
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* Alan Cox : Window clamping
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* Michael Riepe : Bug in tcp_check()
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* Matt Dillon : More TCP improvements and RST bug fixes
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* Matt Dillon : Yet more small nasties remove from the
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* TCP code (Be very nice to this man if
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* tcp finally works 100%) 8)
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* Alan Cox : BSD accept semantics.
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* Alan Cox : Reset on closedown bug.
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* Peter De Schrijver : ENOTCONN check missing in tcp_sendto().
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* Michael Pall : Handle poll() after URG properly in
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* all cases.
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* Michael Pall : Undo the last fix in tcp_read_urg()
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* (multi URG PUSH broke rlogin).
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* Michael Pall : Fix the multi URG PUSH problem in
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* tcp_readable(), poll() after URG
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* works now.
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* Michael Pall : recv(...,MSG_OOB) never blocks in the
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* BSD api.
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* Alan Cox : Changed the semantics of sk->socket to
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* fix a race and a signal problem with
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* accept() and async I/O.
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* Alan Cox : Relaxed the rules on tcp_sendto().
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* Yury Shevchuk : Really fixed accept() blocking problem.
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* Craig I. Hagan : Allow for BSD compatible TIME_WAIT for
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* clients/servers which listen in on
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* fixed ports.
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* Alan Cox : Cleaned the above up and shrank it to
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* a sensible code size.
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* Alan Cox : Self connect lockup fix.
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* Alan Cox : No connect to multicast.
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* Ross Biro : Close unaccepted children on master
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* socket close.
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* Alan Cox : Reset tracing code.
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* Alan Cox : Spurious resets on shutdown.
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* Alan Cox : Giant 15 minute/60 second timer error
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* Alan Cox : Small whoops in polling before an
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* accept.
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* Alan Cox : Kept the state trace facility since
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* it's handy for debugging.
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* Alan Cox : More reset handler fixes.
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* Alan Cox : Started rewriting the code based on
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* the RFC's for other useful protocol
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* references see: Comer, KA9Q NOS, and
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* for a reference on the difference
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* between specifications and how BSD
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* works see the 4.4lite source.
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* A.N.Kuznetsov : Don't time wait on completion of tidy
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* close.
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* Linus Torvalds : Fin/Shutdown & copied_seq changes.
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* Linus Torvalds : Fixed BSD port reuse to work first syn
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* Alan Cox : Reimplemented timers as per the RFC
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* and using multiple timers for sanity.
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* Alan Cox : Small bug fixes, and a lot of new
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* comments.
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* Alan Cox : Fixed dual reader crash by locking
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* the buffers (much like datagram.c)
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* Alan Cox : Fixed stuck sockets in probe. A probe
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* now gets fed up of retrying without
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* (even a no space) answer.
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* Alan Cox : Extracted closing code better
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* Alan Cox : Fixed the closing state machine to
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* resemble the RFC.
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* Alan Cox : More 'per spec' fixes.
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* Jorge Cwik : Even faster checksumming.
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* Alan Cox : tcp_data() doesn't ack illegal PSH
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* only frames. At least one pc tcp stack
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* generates them.
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* Alan Cox : Cache last socket.
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* Alan Cox : Per route irtt.
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* Matt Day : poll()->select() match BSD precisely on error
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* Alan Cox : New buffers
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* Marc Tamsky : Various sk->prot->retransmits and
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* sk->retransmits misupdating fixed.
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* Fixed tcp_write_timeout: stuck close,
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* and TCP syn retries gets used now.
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* Mark Yarvis : In tcp_read_wakeup(), don't send an
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* ack if state is TCP_CLOSED.
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* Alan Cox : Look up device on a retransmit - routes may
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* change. Doesn't yet cope with MSS shrink right
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* but it's a start!
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* Marc Tamsky : Closing in closing fixes.
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* Mike Shaver : RFC1122 verifications.
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* Alan Cox : rcv_saddr errors.
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* Alan Cox : Block double connect().
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* Alan Cox : Small hooks for enSKIP.
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* Alexey Kuznetsov: Path MTU discovery.
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* Alan Cox : Support soft errors.
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* Alan Cox : Fix MTU discovery pathological case
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* when the remote claims no mtu!
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* Marc Tamsky : TCP_CLOSE fix.
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* Colin (G3TNE) : Send a reset on syn ack replies in
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* window but wrong (fixes NT lpd problems)
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* Pedro Roque : Better TCP window handling, delayed ack.
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* Joerg Reuter : No modification of locked buffers in
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* tcp_do_retransmit()
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* Eric Schenk : Changed receiver side silly window
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* avoidance algorithm to BSD style
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* algorithm. This doubles throughput
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* against machines running Solaris,
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* and seems to result in general
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* improvement.
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* Stefan Magdalinski : adjusted tcp_readable() to fix FIONREAD
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* Willy Konynenberg : Transparent proxying support.
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* Mike McLagan : Routing by source
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* Keith Owens : Do proper merging with partial SKB's in
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* tcp_do_sendmsg to avoid burstiness.
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* Eric Schenk : Fix fast close down bug with
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* shutdown() followed by close().
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* Andi Kleen : Make poll agree with SIGIO
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* Salvatore Sanfilippo : Support SO_LINGER with linger == 1 and
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* lingertime == 0 (RFC 793 ABORT Call)
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* Hirokazu Takahashi : Use copy_from_user() instead of
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* csum_and_copy_from_user() if possible.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or(at your option) any later version.
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*
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* Description of States:
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*
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* TCP_SYN_SENT sent a connection request, waiting for ack
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*
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* TCP_SYN_RECV received a connection request, sent ack,
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* waiting for final ack in three-way handshake.
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*
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* TCP_ESTABLISHED connection established
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*
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* TCP_FIN_WAIT1 our side has shutdown, waiting to complete
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* transmission of remaining buffered data
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*
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* TCP_FIN_WAIT2 all buffered data sent, waiting for remote
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* to shutdown
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*
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* TCP_CLOSING both sides have shutdown but we still have
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* data we have to finish sending
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*
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* TCP_TIME_WAIT timeout to catch resent junk before entering
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* closed, can only be entered from FIN_WAIT2
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* or CLOSING. Required because the other end
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* may not have gotten our last ACK causing it
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* to retransmit the data packet (which we ignore)
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*
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* TCP_CLOSE_WAIT remote side has shutdown and is waiting for
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* us to finish writing our data and to shutdown
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* (we have to close() to move on to LAST_ACK)
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*
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* TCP_LAST_ACK out side has shutdown after remote has
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* shutdown. There may still be data in our
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* buffer that we have to finish sending
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*
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* TCP_CLOSE socket is finished
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*/
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#define pr_fmt(fmt) "TCP: " fmt
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#include <crypto/hash.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/fcntl.h>
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#include <linux/poll.h>
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#include <linux/inet_diag.h>
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#include <linux/init.h>
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#include <linux/fs.h>
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#include <linux/skbuff.h>
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#include <linux/scatterlist.h>
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#include <linux/splice.h>
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#include <linux/net.h>
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#include <linux/socket.h>
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#include <linux/random.h>
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#include <linux/bootmem.h>
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#include <linux/highmem.h>
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#include <linux/swap.h>
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#include <linux/cache.h>
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#include <linux/err.h>
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#include <linux/time.h>
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#include <linux/slab.h>
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#include <net/icmp.h>
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#include <net/inet_common.h>
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#include <net/tcp.h>
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#include <net/xfrm.h>
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#include <net/ip.h>
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#include <net/sock.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <net/busy_poll.h>
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int sysctl_tcp_min_tso_segs __read_mostly = 2;
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int sysctl_tcp_autocorking __read_mostly = 1;
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struct percpu_counter tcp_orphan_count;
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EXPORT_SYMBOL_GPL(tcp_orphan_count);
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long sysctl_tcp_mem[3] __read_mostly;
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int sysctl_tcp_wmem[3] __read_mostly;
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int sysctl_tcp_rmem[3] __read_mostly;
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EXPORT_SYMBOL(sysctl_tcp_mem);
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EXPORT_SYMBOL(sysctl_tcp_rmem);
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EXPORT_SYMBOL(sysctl_tcp_wmem);
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atomic_long_t tcp_memory_allocated; /* Current allocated memory. */
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EXPORT_SYMBOL(tcp_memory_allocated);
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/*
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* Current number of TCP sockets.
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*/
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struct percpu_counter tcp_sockets_allocated;
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EXPORT_SYMBOL(tcp_sockets_allocated);
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/*
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* TCP splice context
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*/
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struct tcp_splice_state {
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struct pipe_inode_info *pipe;
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size_t len;
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unsigned int flags;
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};
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/*
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* Pressure flag: try to collapse.
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* Technical note: it is used by multiple contexts non atomically.
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* All the __sk_mem_schedule() is of this nature: accounting
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* is strict, actions are advisory and have some latency.
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*/
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unsigned long tcp_memory_pressure __read_mostly;
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EXPORT_SYMBOL_GPL(tcp_memory_pressure);
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void tcp_enter_memory_pressure(struct sock *sk)
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{
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unsigned long val;
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if (tcp_memory_pressure)
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return;
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val = jiffies;
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if (!val)
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val--;
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if (!cmpxchg(&tcp_memory_pressure, 0, val))
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NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURES);
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}
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EXPORT_SYMBOL_GPL(tcp_enter_memory_pressure);
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void tcp_leave_memory_pressure(struct sock *sk)
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{
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unsigned long val;
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if (!tcp_memory_pressure)
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return;
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val = xchg(&tcp_memory_pressure, 0);
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if (val)
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NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURESCHRONO,
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jiffies_to_msecs(jiffies - val));
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}
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EXPORT_SYMBOL_GPL(tcp_leave_memory_pressure);
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/* Convert seconds to retransmits based on initial and max timeout */
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static u8 secs_to_retrans(int seconds, int timeout, int rto_max)
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{
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u8 res = 0;
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if (seconds > 0) {
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int period = timeout;
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res = 1;
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while (seconds > period && res < 255) {
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res++;
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timeout <<= 1;
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if (timeout > rto_max)
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timeout = rto_max;
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period += timeout;
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}
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}
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return res;
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}
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/* Convert retransmits to seconds based on initial and max timeout */
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static int retrans_to_secs(u8 retrans, int timeout, int rto_max)
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{
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int period = 0;
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if (retrans > 0) {
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period = timeout;
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while (--retrans) {
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timeout <<= 1;
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if (timeout > rto_max)
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timeout = rto_max;
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period += timeout;
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}
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}
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return period;
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}
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static u64 tcp_compute_delivery_rate(const struct tcp_sock *tp)
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{
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u32 rate = READ_ONCE(tp->rate_delivered);
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u32 intv = READ_ONCE(tp->rate_interval_us);
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u64 rate64 = 0;
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if (rate && intv) {
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rate64 = (u64)rate * tp->mss_cache * USEC_PER_SEC;
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do_div(rate64, intv);
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}
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return rate64;
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}
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/* Address-family independent initialization for a tcp_sock.
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*
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* NOTE: A lot of things set to zero explicitly by call to
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* sk_alloc() so need not be done here.
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*/
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void tcp_init_sock(struct sock *sk)
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{
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struct inet_connection_sock *icsk = inet_csk(sk);
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struct tcp_sock *tp = tcp_sk(sk);
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tp->out_of_order_queue = RB_ROOT;
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tcp_init_xmit_timers(sk);
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INIT_LIST_HEAD(&tp->tsq_node);
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icsk->icsk_rto = TCP_TIMEOUT_INIT;
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tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT);
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minmax_reset(&tp->rtt_min, tcp_jiffies32, ~0U);
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/* So many TCP implementations out there (incorrectly) count the
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* initial SYN frame in their delayed-ACK and congestion control
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* algorithms that we must have the following bandaid to talk
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* efficiently to them. -DaveM
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*/
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tp->snd_cwnd = TCP_INIT_CWND;
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/* There's a bubble in the pipe until at least the first ACK. */
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tp->app_limited = ~0U;
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/* See draft-stevens-tcpca-spec-01 for discussion of the
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* initialization of these values.
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*/
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tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
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tp->snd_cwnd_clamp = ~0;
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tp->mss_cache = TCP_MSS_DEFAULT;
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tp->reordering = sock_net(sk)->ipv4.sysctl_tcp_reordering;
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tcp_assign_congestion_control(sk);
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tp->tsoffset = 0;
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sk->sk_state = TCP_CLOSE;
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sk->sk_write_space = sk_stream_write_space;
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sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
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icsk->icsk_sync_mss = tcp_sync_mss;
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sk->sk_sndbuf = sysctl_tcp_wmem[1];
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sk->sk_rcvbuf = sysctl_tcp_rmem[1];
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sk_sockets_allocated_inc(sk);
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}
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EXPORT_SYMBOL(tcp_init_sock);
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static void tcp_tx_timestamp(struct sock *sk, u16 tsflags, struct sk_buff *skb)
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{
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if (tsflags && skb) {
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struct skb_shared_info *shinfo = skb_shinfo(skb);
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struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
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sock_tx_timestamp(sk, tsflags, &shinfo->tx_flags);
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if (tsflags & SOF_TIMESTAMPING_TX_ACK)
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tcb->txstamp_ack = 1;
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if (tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
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shinfo->tskey = TCP_SKB_CB(skb)->seq + skb->len - 1;
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}
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}
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/*
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* Wait for a TCP event.
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*
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* Note that we don't need to lock the socket, as the upper poll layers
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* take care of normal races (between the test and the event) and we don't
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* go look at any of the socket buffers directly.
|
|
*/
|
|
unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
|
|
{
|
|
unsigned int mask;
|
|
struct sock *sk = sock->sk;
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
int state;
|
|
|
|
sock_rps_record_flow(sk);
|
|
|
|
sock_poll_wait(file, sk_sleep(sk), wait);
|
|
|
|
state = sk_state_load(sk);
|
|
if (state == TCP_LISTEN)
|
|
return inet_csk_listen_poll(sk);
|
|
|
|
/* Socket is not locked. We are protected from async events
|
|
* by poll logic and correct handling of state changes
|
|
* made by other threads is impossible in any case.
|
|
*/
|
|
|
|
mask = 0;
|
|
|
|
/*
|
|
* POLLHUP is certainly not done right. But poll() doesn't
|
|
* have a notion of HUP in just one direction, and for a
|
|
* socket the read side is more interesting.
|
|
*
|
|
* Some poll() documentation says that POLLHUP is incompatible
|
|
* with the POLLOUT/POLLWR flags, so somebody should check this
|
|
* all. But careful, it tends to be safer to return too many
|
|
* bits than too few, and you can easily break real applications
|
|
* if you don't tell them that something has hung up!
|
|
*
|
|
* Check-me.
|
|
*
|
|
* Check number 1. POLLHUP is _UNMASKABLE_ event (see UNIX98 and
|
|
* our fs/select.c). It means that after we received EOF,
|
|
* poll always returns immediately, making impossible poll() on write()
|
|
* in state CLOSE_WAIT. One solution is evident --- to set POLLHUP
|
|
* if and only if shutdown has been made in both directions.
|
|
* Actually, it is interesting to look how Solaris and DUX
|
|
* solve this dilemma. I would prefer, if POLLHUP were maskable,
|
|
* then we could set it on SND_SHUTDOWN. BTW examples given
|
|
* in Stevens' books assume exactly this behaviour, it explains
|
|
* why POLLHUP is incompatible with POLLOUT. --ANK
|
|
*
|
|
* NOTE. Check for TCP_CLOSE is added. The goal is to prevent
|
|
* blocking on fresh not-connected or disconnected socket. --ANK
|
|
*/
|
|
if (sk->sk_shutdown == SHUTDOWN_MASK || state == TCP_CLOSE)
|
|
mask |= POLLHUP;
|
|
if (sk->sk_shutdown & RCV_SHUTDOWN)
|
|
mask |= POLLIN | POLLRDNORM | POLLRDHUP;
|
|
|
|
/* Connected or passive Fast Open socket? */
|
|
if (state != TCP_SYN_SENT &&
|
|
(state != TCP_SYN_RECV || tp->fastopen_rsk)) {
|
|
int target = sock_rcvlowat(sk, 0, INT_MAX);
|
|
|
|
if (tp->urg_seq == tp->copied_seq &&
|
|
!sock_flag(sk, SOCK_URGINLINE) &&
|
|
tp->urg_data)
|
|
target++;
|
|
|
|
if (tp->rcv_nxt - tp->copied_seq >= target)
|
|
mask |= POLLIN | POLLRDNORM;
|
|
|
|
if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
|
|
if (sk_stream_is_writeable(sk)) {
|
|
mask |= POLLOUT | POLLWRNORM;
|
|
} else { /* send SIGIO later */
|
|
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
|
|
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
|
|
|
|
/* Race breaker. If space is freed after
|
|
* wspace test but before the flags are set,
|
|
* IO signal will be lost. Memory barrier
|
|
* pairs with the input side.
|
|
*/
|
|
smp_mb__after_atomic();
|
|
if (sk_stream_is_writeable(sk))
|
|
mask |= POLLOUT | POLLWRNORM;
|
|
}
|
|
} else
|
|
mask |= POLLOUT | POLLWRNORM;
|
|
|
|
if (tp->urg_data & TCP_URG_VALID)
|
|
mask |= POLLPRI;
|
|
} else if (state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) {
|
|
/* Active TCP fastopen socket with defer_connect
|
|
* Return POLLOUT so application can call write()
|
|
* in order for kernel to generate SYN+data
|
|
*/
|
|
mask |= POLLOUT | POLLWRNORM;
|
|
}
|
|
/* This barrier is coupled with smp_wmb() in tcp_reset() */
|
|
smp_rmb();
|
|
if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
|
|
mask |= POLLERR;
|
|
|
|
return mask;
|
|
}
|
|
EXPORT_SYMBOL(tcp_poll);
|
|
|
|
int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
int answ;
|
|
bool slow;
|
|
|
|
switch (cmd) {
|
|
case SIOCINQ:
|
|
if (sk->sk_state == TCP_LISTEN)
|
|
return -EINVAL;
|
|
|
|
slow = lock_sock_fast(sk);
|
|
answ = tcp_inq(sk);
|
|
unlock_sock_fast(sk, slow);
|
|
break;
|
|
case SIOCATMARK:
|
|
answ = tp->urg_data && tp->urg_seq == tp->copied_seq;
|
|
break;
|
|
case SIOCOUTQ:
|
|
if (sk->sk_state == TCP_LISTEN)
|
|
return -EINVAL;
|
|
|
|
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
|
|
answ = 0;
|
|
else
|
|
answ = tp->write_seq - tp->snd_una;
|
|
break;
|
|
case SIOCOUTQNSD:
|
|
if (sk->sk_state == TCP_LISTEN)
|
|
return -EINVAL;
|
|
|
|
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
|
|
answ = 0;
|
|
else
|
|
answ = tp->write_seq - tp->snd_nxt;
|
|
break;
|
|
default:
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
return put_user(answ, (int __user *)arg);
|
|
}
|
|
EXPORT_SYMBOL(tcp_ioctl);
|
|
|
|
static inline void tcp_mark_push(struct tcp_sock *tp, struct sk_buff *skb)
|
|
{
|
|
TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH;
|
|
tp->pushed_seq = tp->write_seq;
|
|
}
|
|
|
|
static inline bool forced_push(const struct tcp_sock *tp)
|
|
{
|
|
return after(tp->write_seq, tp->pushed_seq + (tp->max_window >> 1));
|
|
}
|
|
|
|
static void skb_entail(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
|
|
|
|
skb->csum = 0;
|
|
tcb->seq = tcb->end_seq = tp->write_seq;
|
|
tcb->tcp_flags = TCPHDR_ACK;
|
|
tcb->sacked = 0;
|
|
__skb_header_release(skb);
|
|
tcp_add_write_queue_tail(sk, skb);
|
|
sk->sk_wmem_queued += skb->truesize;
|
|
sk_mem_charge(sk, skb->truesize);
|
|
if (tp->nonagle & TCP_NAGLE_PUSH)
|
|
tp->nonagle &= ~TCP_NAGLE_PUSH;
|
|
|
|
tcp_slow_start_after_idle_check(sk);
|
|
}
|
|
|
|
static inline void tcp_mark_urg(struct tcp_sock *tp, int flags)
|
|
{
|
|
if (flags & MSG_OOB)
|
|
tp->snd_up = tp->write_seq;
|
|
}
|
|
|
|
/* If a not yet filled skb is pushed, do not send it if
|
|
* we have data packets in Qdisc or NIC queues :
|
|
* Because TX completion will happen shortly, it gives a chance
|
|
* to coalesce future sendmsg() payload into this skb, without
|
|
* need for a timer, and with no latency trade off.
|
|
* As packets containing data payload have a bigger truesize
|
|
* than pure acks (dataless) packets, the last checks prevent
|
|
* autocorking if we only have an ACK in Qdisc/NIC queues,
|
|
* or if TX completion was delayed after we processed ACK packet.
|
|
*/
|
|
static bool tcp_should_autocork(struct sock *sk, struct sk_buff *skb,
|
|
int size_goal)
|
|
{
|
|
return skb->len < size_goal &&
|
|
sysctl_tcp_autocorking &&
|
|
skb != tcp_write_queue_head(sk) &&
|
|
refcount_read(&sk->sk_wmem_alloc) > skb->truesize;
|
|
}
|
|
|
|
static void tcp_push(struct sock *sk, int flags, int mss_now,
|
|
int nonagle, int size_goal)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct sk_buff *skb;
|
|
|
|
if (!tcp_send_head(sk))
|
|
return;
|
|
|
|
skb = tcp_write_queue_tail(sk);
|
|
if (!(flags & MSG_MORE) || forced_push(tp))
|
|
tcp_mark_push(tp, skb);
|
|
|
|
tcp_mark_urg(tp, flags);
|
|
|
|
if (tcp_should_autocork(sk, skb, size_goal)) {
|
|
|
|
/* avoid atomic op if TSQ_THROTTLED bit is already set */
|
|
if (!test_bit(TSQ_THROTTLED, &sk->sk_tsq_flags)) {
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAUTOCORKING);
|
|
set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags);
|
|
}
|
|
/* It is possible TX completion already happened
|
|
* before we set TSQ_THROTTLED.
|
|
*/
|
|
if (refcount_read(&sk->sk_wmem_alloc) > skb->truesize)
|
|
return;
|
|
}
|
|
|
|
if (flags & MSG_MORE)
|
|
nonagle = TCP_NAGLE_CORK;
|
|
|
|
__tcp_push_pending_frames(sk, mss_now, nonagle);
|
|
}
|
|
|
|
static int tcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
|
|
unsigned int offset, size_t len)
|
|
{
|
|
struct tcp_splice_state *tss = rd_desc->arg.data;
|
|
int ret;
|
|
|
|
ret = skb_splice_bits(skb, skb->sk, offset, tss->pipe,
|
|
min(rd_desc->count, len), tss->flags);
|
|
if (ret > 0)
|
|
rd_desc->count -= ret;
|
|
return ret;
|
|
}
|
|
|
|
static int __tcp_splice_read(struct sock *sk, struct tcp_splice_state *tss)
|
|
{
|
|
/* Store TCP splice context information in read_descriptor_t. */
|
|
read_descriptor_t rd_desc = {
|
|
.arg.data = tss,
|
|
.count = tss->len,
|
|
};
|
|
|
|
return tcp_read_sock(sk, &rd_desc, tcp_splice_data_recv);
|
|
}
|
|
|
|
/**
|
|
* tcp_splice_read - splice data from TCP socket to a pipe
|
|
* @sock: socket to splice from
|
|
* @ppos: position (not valid)
|
|
* @pipe: pipe to splice to
|
|
* @len: number of bytes to splice
|
|
* @flags: splice modifier flags
|
|
*
|
|
* Description:
|
|
* Will read pages from given socket and fill them into a pipe.
|
|
*
|
|
**/
|
|
ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos,
|
|
struct pipe_inode_info *pipe, size_t len,
|
|
unsigned int flags)
|
|
{
|
|
struct sock *sk = sock->sk;
|
|
struct tcp_splice_state tss = {
|
|
.pipe = pipe,
|
|
.len = len,
|
|
.flags = flags,
|
|
};
|
|
long timeo;
|
|
ssize_t spliced;
|
|
int ret;
|
|
|
|
sock_rps_record_flow(sk);
|
|
/*
|
|
* We can't seek on a socket input
|
|
*/
|
|
if (unlikely(*ppos))
|
|
return -ESPIPE;
|
|
|
|
ret = spliced = 0;
|
|
|
|
lock_sock(sk);
|
|
|
|
timeo = sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK);
|
|
while (tss.len) {
|
|
ret = __tcp_splice_read(sk, &tss);
|
|
if (ret < 0)
|
|
break;
|
|
else if (!ret) {
|
|
if (spliced)
|
|
break;
|
|
if (sock_flag(sk, SOCK_DONE))
|
|
break;
|
|
if (sk->sk_err) {
|
|
ret = sock_error(sk);
|
|
break;
|
|
}
|
|
if (sk->sk_shutdown & RCV_SHUTDOWN)
|
|
break;
|
|
if (sk->sk_state == TCP_CLOSE) {
|
|
/*
|
|
* This occurs when user tries to read
|
|
* from never connected socket.
|
|
*/
|
|
if (!sock_flag(sk, SOCK_DONE))
|
|
ret = -ENOTCONN;
|
|
break;
|
|
}
|
|
if (!timeo) {
|
|
ret = -EAGAIN;
|
|
break;
|
|
}
|
|
/* if __tcp_splice_read() got nothing while we have
|
|
* an skb in receive queue, we do not want to loop.
|
|
* This might happen with URG data.
|
|
*/
|
|
if (!skb_queue_empty(&sk->sk_receive_queue))
|
|
break;
|
|
sk_wait_data(sk, &timeo, NULL);
|
|
if (signal_pending(current)) {
|
|
ret = sock_intr_errno(timeo);
|
|
break;
|
|
}
|
|
continue;
|
|
}
|
|
tss.len -= ret;
|
|
spliced += ret;
|
|
|
|
if (!timeo)
|
|
break;
|
|
release_sock(sk);
|
|
lock_sock(sk);
|
|
|
|
if (sk->sk_err || sk->sk_state == TCP_CLOSE ||
|
|
(sk->sk_shutdown & RCV_SHUTDOWN) ||
|
|
signal_pending(current))
|
|
break;
|
|
}
|
|
|
|
release_sock(sk);
|
|
|
|
if (spliced)
|
|
return spliced;
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(tcp_splice_read);
|
|
|
|
struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
|
|
bool force_schedule)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
/* The TCP header must be at least 32-bit aligned. */
|
|
size = ALIGN(size, 4);
|
|
|
|
if (unlikely(tcp_under_memory_pressure(sk)))
|
|
sk_mem_reclaim_partial(sk);
|
|
|
|
skb = alloc_skb_fclone(size + sk->sk_prot->max_header, gfp);
|
|
if (likely(skb)) {
|
|
bool mem_scheduled;
|
|
|
|
if (force_schedule) {
|
|
mem_scheduled = true;
|
|
sk_forced_mem_schedule(sk, skb->truesize);
|
|
} else {
|
|
mem_scheduled = sk_wmem_schedule(sk, skb->truesize);
|
|
}
|
|
if (likely(mem_scheduled)) {
|
|
skb_reserve(skb, sk->sk_prot->max_header);
|
|
/*
|
|
* Make sure that we have exactly size bytes
|
|
* available to the caller, no more, no less.
|
|
*/
|
|
skb->reserved_tailroom = skb->end - skb->tail - size;
|
|
return skb;
|
|
}
|
|
__kfree_skb(skb);
|
|
} else {
|
|
sk->sk_prot->enter_memory_pressure(sk);
|
|
sk_stream_moderate_sndbuf(sk);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now,
|
|
int large_allowed)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
u32 new_size_goal, size_goal;
|
|
|
|
if (!large_allowed || !sk_can_gso(sk))
|
|
return mss_now;
|
|
|
|
/* Note : tcp_tso_autosize() will eventually split this later */
|
|
new_size_goal = sk->sk_gso_max_size - 1 - MAX_TCP_HEADER;
|
|
new_size_goal = tcp_bound_to_half_wnd(tp, new_size_goal);
|
|
|
|
/* We try hard to avoid divides here */
|
|
size_goal = tp->gso_segs * mss_now;
|
|
if (unlikely(new_size_goal < size_goal ||
|
|
new_size_goal >= size_goal + mss_now)) {
|
|
tp->gso_segs = min_t(u16, new_size_goal / mss_now,
|
|
sk->sk_gso_max_segs);
|
|
size_goal = tp->gso_segs * mss_now;
|
|
}
|
|
|
|
return max(size_goal, mss_now);
|
|
}
|
|
|
|
static int tcp_send_mss(struct sock *sk, int *size_goal, int flags)
|
|
{
|
|
int mss_now;
|
|
|
|
mss_now = tcp_current_mss(sk);
|
|
*size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB));
|
|
|
|
return mss_now;
|
|
}
|
|
|
|
ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset,
|
|
size_t size, int flags)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
int mss_now, size_goal;
|
|
int err;
|
|
ssize_t copied;
|
|
long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
|
|
|
|
/* Wait for a connection to finish. One exception is TCP Fast Open
|
|
* (passive side) where data is allowed to be sent before a connection
|
|
* is fully established.
|
|
*/
|
|
if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) &&
|
|
!tcp_passive_fastopen(sk)) {
|
|
err = sk_stream_wait_connect(sk, &timeo);
|
|
if (err != 0)
|
|
goto out_err;
|
|
}
|
|
|
|
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
|
|
|
|
mss_now = tcp_send_mss(sk, &size_goal, flags);
|
|
copied = 0;
|
|
|
|
err = -EPIPE;
|
|
if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
|
|
goto out_err;
|
|
|
|
while (size > 0) {
|
|
struct sk_buff *skb = tcp_write_queue_tail(sk);
|
|
int copy, i;
|
|
bool can_coalesce;
|
|
|
|
if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0 ||
|
|
!tcp_skb_can_collapse_to(skb)) {
|
|
new_segment:
|
|
if (!sk_stream_memory_free(sk))
|
|
goto wait_for_sndbuf;
|
|
|
|
skb = sk_stream_alloc_skb(sk, 0, sk->sk_allocation,
|
|
skb_queue_empty(&sk->sk_write_queue));
|
|
if (!skb)
|
|
goto wait_for_memory;
|
|
|
|
skb_entail(sk, skb);
|
|
copy = size_goal;
|
|
}
|
|
|
|
if (copy > size)
|
|
copy = size;
|
|
|
|
i = skb_shinfo(skb)->nr_frags;
|
|
can_coalesce = skb_can_coalesce(skb, i, page, offset);
|
|
if (!can_coalesce && i >= sysctl_max_skb_frags) {
|
|
tcp_mark_push(tp, skb);
|
|
goto new_segment;
|
|
}
|
|
if (!sk_wmem_schedule(sk, copy))
|
|
goto wait_for_memory;
|
|
|
|
if (can_coalesce) {
|
|
skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
|
|
} else {
|
|
get_page(page);
|
|
skb_fill_page_desc(skb, i, page, offset, copy);
|
|
}
|
|
skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
|
|
|
|
skb->len += copy;
|
|
skb->data_len += copy;
|
|
skb->truesize += copy;
|
|
sk->sk_wmem_queued += copy;
|
|
sk_mem_charge(sk, copy);
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
tp->write_seq += copy;
|
|
TCP_SKB_CB(skb)->end_seq += copy;
|
|
tcp_skb_pcount_set(skb, 0);
|
|
|
|
if (!copied)
|
|
TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
|
|
|
|
copied += copy;
|
|
offset += copy;
|
|
size -= copy;
|
|
if (!size)
|
|
goto out;
|
|
|
|
if (skb->len < size_goal || (flags & MSG_OOB))
|
|
continue;
|
|
|
|
if (forced_push(tp)) {
|
|
tcp_mark_push(tp, skb);
|
|
__tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH);
|
|
} else if (skb == tcp_send_head(sk))
|
|
tcp_push_one(sk, mss_now);
|
|
continue;
|
|
|
|
wait_for_sndbuf:
|
|
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
|
|
wait_for_memory:
|
|
tcp_push(sk, flags & ~MSG_MORE, mss_now,
|
|
TCP_NAGLE_PUSH, size_goal);
|
|
|
|
err = sk_stream_wait_memory(sk, &timeo);
|
|
if (err != 0)
|
|
goto do_error;
|
|
|
|
mss_now = tcp_send_mss(sk, &size_goal, flags);
|
|
}
|
|
|
|
out:
|
|
if (copied) {
|
|
tcp_tx_timestamp(sk, sk->sk_tsflags, tcp_write_queue_tail(sk));
|
|
if (!(flags & MSG_SENDPAGE_NOTLAST))
|
|
tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
|
|
}
|
|
return copied;
|
|
|
|
do_error:
|
|
if (copied)
|
|
goto out;
|
|
out_err:
|
|
/* make sure we wake any epoll edge trigger waiter */
|
|
if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 &&
|
|
err == -EAGAIN)) {
|
|
sk->sk_write_space(sk);
|
|
tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED);
|
|
}
|
|
return sk_stream_error(sk, flags, err);
|
|
}
|
|
EXPORT_SYMBOL_GPL(do_tcp_sendpages);
|
|
|
|
int tcp_sendpage_locked(struct sock *sk, struct page *page, int offset,
|
|
size_t size, int flags)
|
|
{
|
|
if (!(sk->sk_route_caps & NETIF_F_SG) ||
|
|
!sk_check_csum_caps(sk))
|
|
return sock_no_sendpage(sk->sk_socket, page, offset, size,
|
|
flags);
|
|
|
|
tcp_rate_check_app_limited(sk); /* is sending application-limited? */
|
|
|
|
return do_tcp_sendpages(sk, page, offset, size, flags);
|
|
}
|
|
|
|
int tcp_sendpage(struct sock *sk, struct page *page, int offset,
|
|
size_t size, int flags)
|
|
{
|
|
int ret;
|
|
|
|
lock_sock(sk);
|
|
ret = tcp_sendpage_locked(sk, page, offset, size, flags);
|
|
release_sock(sk);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(tcp_sendpage);
|
|
|
|
/* Do not bother using a page frag for very small frames.
|
|
* But use this heuristic only for the first skb in write queue.
|
|
*
|
|
* Having no payload in skb->head allows better SACK shifting
|
|
* in tcp_shift_skb_data(), reducing sack/rack overhead, because
|
|
* write queue has less skbs.
|
|
* Each skb can hold up to MAX_SKB_FRAGS * 32Kbytes, or ~0.5 MB.
|
|
* This also speeds up tso_fragment(), since it wont fallback
|
|
* to tcp_fragment().
|
|
*/
|
|
static int linear_payload_sz(bool first_skb)
|
|
{
|
|
if (first_skb)
|
|
return SKB_WITH_OVERHEAD(2048 - MAX_TCP_HEADER);
|
|
return 0;
|
|
}
|
|
|
|
static int select_size(const struct sock *sk, bool sg, bool first_skb)
|
|
{
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
int tmp = tp->mss_cache;
|
|
|
|
if (sg) {
|
|
if (sk_can_gso(sk)) {
|
|
tmp = linear_payload_sz(first_skb);
|
|
} else {
|
|
int pgbreak = SKB_MAX_HEAD(MAX_TCP_HEADER);
|
|
|
|
if (tmp >= pgbreak &&
|
|
tmp <= pgbreak + (MAX_SKB_FRAGS - 1) * PAGE_SIZE)
|
|
tmp = pgbreak;
|
|
}
|
|
}
|
|
|
|
return tmp;
|
|
}
|
|
|
|
void tcp_free_fastopen_req(struct tcp_sock *tp)
|
|
{
|
|
if (tp->fastopen_req) {
|
|
kfree(tp->fastopen_req);
|
|
tp->fastopen_req = NULL;
|
|
}
|
|
}
|
|
|
|
static int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg,
|
|
int *copied, size_t size)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct sockaddr *uaddr = msg->msg_name;
|
|
int err, flags;
|
|
|
|
if (!(sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) ||
|
|
(uaddr && msg->msg_namelen >= sizeof(uaddr->sa_family) &&
|
|
uaddr->sa_family == AF_UNSPEC))
|
|
return -EOPNOTSUPP;
|
|
if (tp->fastopen_req)
|
|
return -EALREADY; /* Another Fast Open is in progress */
|
|
|
|
tp->fastopen_req = kzalloc(sizeof(struct tcp_fastopen_request),
|
|
sk->sk_allocation);
|
|
if (unlikely(!tp->fastopen_req))
|
|
return -ENOBUFS;
|
|
tp->fastopen_req->data = msg;
|
|
tp->fastopen_req->size = size;
|
|
|
|
if (inet->defer_connect) {
|
|
err = tcp_connect(sk);
|
|
/* Same failure procedure as in tcp_v4/6_connect */
|
|
if (err) {
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
inet->inet_dport = 0;
|
|
sk->sk_route_caps = 0;
|
|
}
|
|
}
|
|
flags = (msg->msg_flags & MSG_DONTWAIT) ? O_NONBLOCK : 0;
|
|
err = __inet_stream_connect(sk->sk_socket, uaddr,
|
|
msg->msg_namelen, flags, 1);
|
|
/* fastopen_req could already be freed in __inet_stream_connect
|
|
* if the connection times out or gets rst
|
|
*/
|
|
if (tp->fastopen_req) {
|
|
*copied = tp->fastopen_req->copied;
|
|
tcp_free_fastopen_req(tp);
|
|
inet->defer_connect = 0;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct ubuf_info *uarg = NULL;
|
|
struct sk_buff *skb;
|
|
struct sockcm_cookie sockc;
|
|
int flags, err, copied = 0;
|
|
int mss_now = 0, size_goal, copied_syn = 0;
|
|
bool process_backlog = false;
|
|
bool sg;
|
|
long timeo;
|
|
|
|
flags = msg->msg_flags;
|
|
|
|
if (flags & MSG_ZEROCOPY && size) {
|
|
if (sk->sk_state != TCP_ESTABLISHED) {
|
|
err = -EINVAL;
|
|
goto out_err;
|
|
}
|
|
|
|
skb = tcp_send_head(sk) ? tcp_write_queue_tail(sk) : NULL;
|
|
uarg = sock_zerocopy_realloc(sk, size, skb_zcopy(skb));
|
|
if (!uarg) {
|
|
err = -ENOBUFS;
|
|
goto out_err;
|
|
}
|
|
|
|
/* skb may be freed in main loop, keep extra ref on uarg */
|
|
sock_zerocopy_get(uarg);
|
|
if (!(sk_check_csum_caps(sk) && sk->sk_route_caps & NETIF_F_SG))
|
|
uarg->zerocopy = 0;
|
|
}
|
|
|
|
if (unlikely(flags & MSG_FASTOPEN || inet_sk(sk)->defer_connect)) {
|
|
err = tcp_sendmsg_fastopen(sk, msg, &copied_syn, size);
|
|
if (err == -EINPROGRESS && copied_syn > 0)
|
|
goto out;
|
|
else if (err)
|
|
goto out_err;
|
|
}
|
|
|
|
timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
|
|
|
|
tcp_rate_check_app_limited(sk); /* is sending application-limited? */
|
|
|
|
/* Wait for a connection to finish. One exception is TCP Fast Open
|
|
* (passive side) where data is allowed to be sent before a connection
|
|
* is fully established.
|
|
*/
|
|
if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) &&
|
|
!tcp_passive_fastopen(sk)) {
|
|
err = sk_stream_wait_connect(sk, &timeo);
|
|
if (err != 0)
|
|
goto do_error;
|
|
}
|
|
|
|
if (unlikely(tp->repair)) {
|
|
if (tp->repair_queue == TCP_RECV_QUEUE) {
|
|
copied = tcp_send_rcvq(sk, msg, size);
|
|
goto out_nopush;
|
|
}
|
|
|
|
err = -EINVAL;
|
|
if (tp->repair_queue == TCP_NO_QUEUE)
|
|
goto out_err;
|
|
|
|
/* 'common' sending to sendq */
|
|
}
|
|
|
|
sockc.tsflags = sk->sk_tsflags;
|
|
if (msg->msg_controllen) {
|
|
err = sock_cmsg_send(sk, msg, &sockc);
|
|
if (unlikely(err)) {
|
|
err = -EINVAL;
|
|
goto out_err;
|
|
}
|
|
}
|
|
|
|
/* This should be in poll */
|
|
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
|
|
|
|
/* Ok commence sending. */
|
|
copied = 0;
|
|
|
|
restart:
|
|
mss_now = tcp_send_mss(sk, &size_goal, flags);
|
|
|
|
err = -EPIPE;
|
|
if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
|
|
goto do_error;
|
|
|
|
sg = !!(sk->sk_route_caps & NETIF_F_SG);
|
|
|
|
while (msg_data_left(msg)) {
|
|
int copy = 0;
|
|
int max = size_goal;
|
|
|
|
skb = tcp_write_queue_tail(sk);
|
|
if (tcp_send_head(sk)) {
|
|
if (skb->ip_summed == CHECKSUM_NONE)
|
|
max = mss_now;
|
|
copy = max - skb->len;
|
|
}
|
|
|
|
if (copy <= 0 || !tcp_skb_can_collapse_to(skb)) {
|
|
bool first_skb;
|
|
|
|
new_segment:
|
|
/* Allocate new segment. If the interface is SG,
|
|
* allocate skb fitting to single page.
|
|
*/
|
|
if (!sk_stream_memory_free(sk))
|
|
goto wait_for_sndbuf;
|
|
|
|
if (process_backlog && sk_flush_backlog(sk)) {
|
|
process_backlog = false;
|
|
goto restart;
|
|
}
|
|
first_skb = skb_queue_empty(&sk->sk_write_queue);
|
|
skb = sk_stream_alloc_skb(sk,
|
|
select_size(sk, sg, first_skb),
|
|
sk->sk_allocation,
|
|
first_skb);
|
|
if (!skb)
|
|
goto wait_for_memory;
|
|
|
|
process_backlog = true;
|
|
/*
|
|
* Check whether we can use HW checksum.
|
|
*/
|
|
if (sk_check_csum_caps(sk))
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
|
|
skb_entail(sk, skb);
|
|
copy = size_goal;
|
|
max = size_goal;
|
|
|
|
/* All packets are restored as if they have
|
|
* already been sent. skb_mstamp isn't set to
|
|
* avoid wrong rtt estimation.
|
|
*/
|
|
if (tp->repair)
|
|
TCP_SKB_CB(skb)->sacked |= TCPCB_REPAIRED;
|
|
}
|
|
|
|
/* Try to append data to the end of skb. */
|
|
if (copy > msg_data_left(msg))
|
|
copy = msg_data_left(msg);
|
|
|
|
/* Where to copy to? */
|
|
if (skb_availroom(skb) > 0) {
|
|
/* We have some space in skb head. Superb! */
|
|
copy = min_t(int, copy, skb_availroom(skb));
|
|
err = skb_add_data_nocache(sk, skb, &msg->msg_iter, copy);
|
|
if (err)
|
|
goto do_fault;
|
|
} else if (!uarg || !uarg->zerocopy) {
|
|
bool merge = true;
|
|
int i = skb_shinfo(skb)->nr_frags;
|
|
struct page_frag *pfrag = sk_page_frag(sk);
|
|
|
|
if (!sk_page_frag_refill(sk, pfrag))
|
|
goto wait_for_memory;
|
|
|
|
if (!skb_can_coalesce(skb, i, pfrag->page,
|
|
pfrag->offset)) {
|
|
if (i >= sysctl_max_skb_frags || !sg) {
|
|
tcp_mark_push(tp, skb);
|
|
goto new_segment;
|
|
}
|
|
merge = false;
|
|
}
|
|
|
|
copy = min_t(int, copy, pfrag->size - pfrag->offset);
|
|
|
|
if (!sk_wmem_schedule(sk, copy))
|
|
goto wait_for_memory;
|
|
|
|
err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb,
|
|
pfrag->page,
|
|
pfrag->offset,
|
|
copy);
|
|
if (err)
|
|
goto do_error;
|
|
|
|
/* Update the skb. */
|
|
if (merge) {
|
|
skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
|
|
} else {
|
|
skb_fill_page_desc(skb, i, pfrag->page,
|
|
pfrag->offset, copy);
|
|
page_ref_inc(pfrag->page);
|
|
}
|
|
pfrag->offset += copy;
|
|
} else {
|
|
err = skb_zerocopy_iter_stream(sk, skb, msg, copy, uarg);
|
|
if (err == -EMSGSIZE || err == -EEXIST)
|
|
goto new_segment;
|
|
if (err < 0)
|
|
goto do_error;
|
|
copy = err;
|
|
}
|
|
|
|
if (!copied)
|
|
TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
|
|
|
|
tp->write_seq += copy;
|
|
TCP_SKB_CB(skb)->end_seq += copy;
|
|
tcp_skb_pcount_set(skb, 0);
|
|
|
|
copied += copy;
|
|
if (!msg_data_left(msg)) {
|
|
if (unlikely(flags & MSG_EOR))
|
|
TCP_SKB_CB(skb)->eor = 1;
|
|
goto out;
|
|
}
|
|
|
|
if (skb->len < max || (flags & MSG_OOB) || unlikely(tp->repair))
|
|
continue;
|
|
|
|
if (forced_push(tp)) {
|
|
tcp_mark_push(tp, skb);
|
|
__tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH);
|
|
} else if (skb == tcp_send_head(sk))
|
|
tcp_push_one(sk, mss_now);
|
|
continue;
|
|
|
|
wait_for_sndbuf:
|
|
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
|
|
wait_for_memory:
|
|
if (copied)
|
|
tcp_push(sk, flags & ~MSG_MORE, mss_now,
|
|
TCP_NAGLE_PUSH, size_goal);
|
|
|
|
err = sk_stream_wait_memory(sk, &timeo);
|
|
if (err != 0)
|
|
goto do_error;
|
|
|
|
mss_now = tcp_send_mss(sk, &size_goal, flags);
|
|
}
|
|
|
|
out:
|
|
if (copied) {
|
|
tcp_tx_timestamp(sk, sockc.tsflags, tcp_write_queue_tail(sk));
|
|
tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
|
|
}
|
|
out_nopush:
|
|
sock_zerocopy_put(uarg);
|
|
return copied + copied_syn;
|
|
|
|
do_fault:
|
|
if (!skb->len) {
|
|
tcp_unlink_write_queue(skb, sk);
|
|
/* It is the one place in all of TCP, except connection
|
|
* reset, where we can be unlinking the send_head.
|
|
*/
|
|
tcp_check_send_head(sk, skb);
|
|
sk_wmem_free_skb(sk, skb);
|
|
}
|
|
|
|
do_error:
|
|
if (copied + copied_syn)
|
|
goto out;
|
|
out_err:
|
|
sock_zerocopy_put_abort(uarg);
|
|
err = sk_stream_error(sk, flags, err);
|
|
/* make sure we wake any epoll edge trigger waiter */
|
|
if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 &&
|
|
err == -EAGAIN)) {
|
|
sk->sk_write_space(sk);
|
|
tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
|
|
{
|
|
int ret;
|
|
|
|
lock_sock(sk);
|
|
ret = tcp_sendmsg_locked(sk, msg, size);
|
|
release_sock(sk);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(tcp_sendmsg);
|
|
|
|
/*
|
|
* Handle reading urgent data. BSD has very simple semantics for
|
|
* this, no blocking and very strange errors 8)
|
|
*/
|
|
|
|
static int tcp_recv_urg(struct sock *sk, struct msghdr *msg, int len, int flags)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
/* No URG data to read. */
|
|
if (sock_flag(sk, SOCK_URGINLINE) || !tp->urg_data ||
|
|
tp->urg_data == TCP_URG_READ)
|
|
return -EINVAL; /* Yes this is right ! */
|
|
|
|
if (sk->sk_state == TCP_CLOSE && !sock_flag(sk, SOCK_DONE))
|
|
return -ENOTCONN;
|
|
|
|
if (tp->urg_data & TCP_URG_VALID) {
|
|
int err = 0;
|
|
char c = tp->urg_data;
|
|
|
|
if (!(flags & MSG_PEEK))
|
|
tp->urg_data = TCP_URG_READ;
|
|
|
|
/* Read urgent data. */
|
|
msg->msg_flags |= MSG_OOB;
|
|
|
|
if (len > 0) {
|
|
if (!(flags & MSG_TRUNC))
|
|
err = memcpy_to_msg(msg, &c, 1);
|
|
len = 1;
|
|
} else
|
|
msg->msg_flags |= MSG_TRUNC;
|
|
|
|
return err ? -EFAULT : len;
|
|
}
|
|
|
|
if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN))
|
|
return 0;
|
|
|
|
/* Fixed the recv(..., MSG_OOB) behaviour. BSD docs and
|
|
* the available implementations agree in this case:
|
|
* this call should never block, independent of the
|
|
* blocking state of the socket.
|
|
* Mike <pall@rz.uni-karlsruhe.de>
|
|
*/
|
|
return -EAGAIN;
|
|
}
|
|
|
|
static int tcp_peek_sndq(struct sock *sk, struct msghdr *msg, int len)
|
|
{
|
|
struct sk_buff *skb;
|
|
int copied = 0, err = 0;
|
|
|
|
/* XXX -- need to support SO_PEEK_OFF */
|
|
|
|
skb_queue_walk(&sk->sk_write_queue, skb) {
|
|
err = skb_copy_datagram_msg(skb, 0, msg, skb->len);
|
|
if (err)
|
|
break;
|
|
|
|
copied += skb->len;
|
|
}
|
|
|
|
return err ?: copied;
|
|
}
|
|
|
|
/* Clean up the receive buffer for full frames taken by the user,
|
|
* then send an ACK if necessary. COPIED is the number of bytes
|
|
* tcp_recvmsg has given to the user so far, it speeds up the
|
|
* calculation of whether or not we must ACK for the sake of
|
|
* a window update.
|
|
*/
|
|
static void tcp_cleanup_rbuf(struct sock *sk, int copied)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
bool time_to_ack = false;
|
|
|
|
struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
|
|
|
|
WARN(skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq),
|
|
"cleanup rbuf bug: copied %X seq %X rcvnxt %X\n",
|
|
tp->copied_seq, TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt);
|
|
|
|
if (inet_csk_ack_scheduled(sk)) {
|
|
const struct inet_connection_sock *icsk = inet_csk(sk);
|
|
/* Delayed ACKs frequently hit locked sockets during bulk
|
|
* receive. */
|
|
if (icsk->icsk_ack.blocked ||
|
|
/* Once-per-two-segments ACK was not sent by tcp_input.c */
|
|
tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss ||
|
|
/*
|
|
* If this read emptied read buffer, we send ACK, if
|
|
* connection is not bidirectional, user drained
|
|
* receive buffer and there was a small segment
|
|
* in queue.
|
|
*/
|
|
(copied > 0 &&
|
|
((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) ||
|
|
((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) &&
|
|
!icsk->icsk_ack.pingpong)) &&
|
|
!atomic_read(&sk->sk_rmem_alloc)))
|
|
time_to_ack = true;
|
|
}
|
|
|
|
/* We send an ACK if we can now advertise a non-zero window
|
|
* which has been raised "significantly".
|
|
*
|
|
* Even if window raised up to infinity, do not send window open ACK
|
|
* in states, where we will not receive more. It is useless.
|
|
*/
|
|
if (copied > 0 && !time_to_ack && !(sk->sk_shutdown & RCV_SHUTDOWN)) {
|
|
__u32 rcv_window_now = tcp_receive_window(tp);
|
|
|
|
/* Optimize, __tcp_select_window() is not cheap. */
|
|
if (2*rcv_window_now <= tp->window_clamp) {
|
|
__u32 new_window = __tcp_select_window(sk);
|
|
|
|
/* Send ACK now, if this read freed lots of space
|
|
* in our buffer. Certainly, new_window is new window.
|
|
* We can advertise it now, if it is not less than current one.
|
|
* "Lots" means "at least twice" here.
|
|
*/
|
|
if (new_window && new_window >= 2 * rcv_window_now)
|
|
time_to_ack = true;
|
|
}
|
|
}
|
|
if (time_to_ack)
|
|
tcp_send_ack(sk);
|
|
}
|
|
|
|
static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
|
|
{
|
|
struct sk_buff *skb;
|
|
u32 offset;
|
|
|
|
while ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) {
|
|
offset = seq - TCP_SKB_CB(skb)->seq;
|
|
if (unlikely(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
|
|
pr_err_once("%s: found a SYN, please report !\n", __func__);
|
|
offset--;
|
|
}
|
|
if (offset < skb->len || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) {
|
|
*off = offset;
|
|
return skb;
|
|
}
|
|
/* This looks weird, but this can happen if TCP collapsing
|
|
* splitted a fat GRO packet, while we released socket lock
|
|
* in skb_splice_bits()
|
|
*/
|
|
sk_eat_skb(sk, skb);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* This routine provides an alternative to tcp_recvmsg() for routines
|
|
* that would like to handle copying from skbuffs directly in 'sendfile'
|
|
* fashion.
|
|
* Note:
|
|
* - It is assumed that the socket was locked by the caller.
|
|
* - The routine does not block.
|
|
* - At present, there is no support for reading OOB data
|
|
* or for 'peeking' the socket using this routine
|
|
* (although both would be easy to implement).
|
|
*/
|
|
int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
|
|
sk_read_actor_t recv_actor)
|
|
{
|
|
struct sk_buff *skb;
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
u32 seq = tp->copied_seq;
|
|
u32 offset;
|
|
int copied = 0;
|
|
|
|
if (sk->sk_state == TCP_LISTEN)
|
|
return -ENOTCONN;
|
|
while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) {
|
|
if (offset < skb->len) {
|
|
int used;
|
|
size_t len;
|
|
|
|
len = skb->len - offset;
|
|
/* Stop reading if we hit a patch of urgent data */
|
|
if (tp->urg_data) {
|
|
u32 urg_offset = tp->urg_seq - seq;
|
|
if (urg_offset < len)
|
|
len = urg_offset;
|
|
if (!len)
|
|
break;
|
|
}
|
|
used = recv_actor(desc, skb, offset, len);
|
|
if (used <= 0) {
|
|
if (!copied)
|
|
copied = used;
|
|
break;
|
|
} else if (used <= len) {
|
|
seq += used;
|
|
copied += used;
|
|
offset += used;
|
|
}
|
|
/* If recv_actor drops the lock (e.g. TCP splice
|
|
* receive) the skb pointer might be invalid when
|
|
* getting here: tcp_collapse might have deleted it
|
|
* while aggregating skbs from the socket queue.
|
|
*/
|
|
skb = tcp_recv_skb(sk, seq - 1, &offset);
|
|
if (!skb)
|
|
break;
|
|
/* TCP coalescing might have appended data to the skb.
|
|
* Try to splice more frags
|
|
*/
|
|
if (offset + 1 != skb->len)
|
|
continue;
|
|
}
|
|
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) {
|
|
sk_eat_skb(sk, skb);
|
|
++seq;
|
|
break;
|
|
}
|
|
sk_eat_skb(sk, skb);
|
|
if (!desc->count)
|
|
break;
|
|
tp->copied_seq = seq;
|
|
}
|
|
tp->copied_seq = seq;
|
|
|
|
tcp_rcv_space_adjust(sk);
|
|
|
|
/* Clean up data we have read: This will do ACK frames. */
|
|
if (copied > 0) {
|
|
tcp_recv_skb(sk, seq, &offset);
|
|
tcp_cleanup_rbuf(sk, copied);
|
|
}
|
|
return copied;
|
|
}
|
|
EXPORT_SYMBOL(tcp_read_sock);
|
|
|
|
int tcp_peek_len(struct socket *sock)
|
|
{
|
|
return tcp_inq(sock->sk);
|
|
}
|
|
EXPORT_SYMBOL(tcp_peek_len);
|
|
|
|
/*
|
|
* This routine copies from a sock struct into the user buffer.
|
|
*
|
|
* Technical note: in 2.3 we work on _locked_ socket, so that
|
|
* tricks with *seq access order and skb->users are not required.
|
|
* Probably, code can be easily improved even more.
|
|
*/
|
|
|
|
int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
|
|
int flags, int *addr_len)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
int copied = 0;
|
|
u32 peek_seq;
|
|
u32 *seq;
|
|
unsigned long used;
|
|
int err;
|
|
int target; /* Read at least this many bytes */
|
|
long timeo;
|
|
struct sk_buff *skb, *last;
|
|
u32 urg_hole = 0;
|
|
|
|
if (unlikely(flags & MSG_ERRQUEUE))
|
|
return inet_recv_error(sk, msg, len, addr_len);
|
|
|
|
if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue) &&
|
|
(sk->sk_state == TCP_ESTABLISHED))
|
|
sk_busy_loop(sk, nonblock);
|
|
|
|
lock_sock(sk);
|
|
|
|
err = -ENOTCONN;
|
|
if (sk->sk_state == TCP_LISTEN)
|
|
goto out;
|
|
|
|
timeo = sock_rcvtimeo(sk, nonblock);
|
|
|
|
/* Urgent data needs to be handled specially. */
|
|
if (flags & MSG_OOB)
|
|
goto recv_urg;
|
|
|
|
if (unlikely(tp->repair)) {
|
|
err = -EPERM;
|
|
if (!(flags & MSG_PEEK))
|
|
goto out;
|
|
|
|
if (tp->repair_queue == TCP_SEND_QUEUE)
|
|
goto recv_sndq;
|
|
|
|
err = -EINVAL;
|
|
if (tp->repair_queue == TCP_NO_QUEUE)
|
|
goto out;
|
|
|
|
/* 'common' recv queue MSG_PEEK-ing */
|
|
}
|
|
|
|
seq = &tp->copied_seq;
|
|
if (flags & MSG_PEEK) {
|
|
peek_seq = tp->copied_seq;
|
|
seq = &peek_seq;
|
|
}
|
|
|
|
target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
|
|
|
|
do {
|
|
u32 offset;
|
|
|
|
/* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */
|
|
if (tp->urg_data && tp->urg_seq == *seq) {
|
|
if (copied)
|
|
break;
|
|
if (signal_pending(current)) {
|
|
copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Next get a buffer. */
|
|
|
|
last = skb_peek_tail(&sk->sk_receive_queue);
|
|
skb_queue_walk(&sk->sk_receive_queue, skb) {
|
|
last = skb;
|
|
/* Now that we have two receive queues this
|
|
* shouldn't happen.
|
|
*/
|
|
if (WARN(before(*seq, TCP_SKB_CB(skb)->seq),
|
|
"recvmsg bug: copied %X seq %X rcvnxt %X fl %X\n",
|
|
*seq, TCP_SKB_CB(skb)->seq, tp->rcv_nxt,
|
|
flags))
|
|
break;
|
|
|
|
offset = *seq - TCP_SKB_CB(skb)->seq;
|
|
if (unlikely(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
|
|
pr_err_once("%s: found a SYN, please report !\n", __func__);
|
|
offset--;
|
|
}
|
|
if (offset < skb->len)
|
|
goto found_ok_skb;
|
|
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
|
|
goto found_fin_ok;
|
|
WARN(!(flags & MSG_PEEK),
|
|
"recvmsg bug 2: copied %X seq %X rcvnxt %X fl %X\n",
|
|
*seq, TCP_SKB_CB(skb)->seq, tp->rcv_nxt, flags);
|
|
}
|
|
|
|
/* Well, if we have backlog, try to process it now yet. */
|
|
|
|
if (copied >= target && !sk->sk_backlog.tail)
|
|
break;
|
|
|
|
if (copied) {
|
|
if (sk->sk_err ||
|
|
sk->sk_state == TCP_CLOSE ||
|
|
(sk->sk_shutdown & RCV_SHUTDOWN) ||
|
|
!timeo ||
|
|
signal_pending(current))
|
|
break;
|
|
} else {
|
|
if (sock_flag(sk, SOCK_DONE))
|
|
break;
|
|
|
|
if (sk->sk_err) {
|
|
copied = sock_error(sk);
|
|
break;
|
|
}
|
|
|
|
if (sk->sk_shutdown & RCV_SHUTDOWN)
|
|
break;
|
|
|
|
if (sk->sk_state == TCP_CLOSE) {
|
|
if (!sock_flag(sk, SOCK_DONE)) {
|
|
/* This occurs when user tries to read
|
|
* from never connected socket.
|
|
*/
|
|
copied = -ENOTCONN;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (!timeo) {
|
|
copied = -EAGAIN;
|
|
break;
|
|
}
|
|
|
|
if (signal_pending(current)) {
|
|
copied = sock_intr_errno(timeo);
|
|
break;
|
|
}
|
|
}
|
|
|
|
tcp_cleanup_rbuf(sk, copied);
|
|
|
|
if (copied >= target) {
|
|
/* Do not sleep, just process backlog. */
|
|
release_sock(sk);
|
|
lock_sock(sk);
|
|
} else {
|
|
sk_wait_data(sk, &timeo, last);
|
|
}
|
|
|
|
if ((flags & MSG_PEEK) &&
|
|
(peek_seq - copied - urg_hole != tp->copied_seq)) {
|
|
net_dbg_ratelimited("TCP(%s:%d): Application bug, race in MSG_PEEK\n",
|
|
current->comm,
|
|
task_pid_nr(current));
|
|
peek_seq = tp->copied_seq;
|
|
}
|
|
continue;
|
|
|
|
found_ok_skb:
|
|
/* Ok so how much can we use? */
|
|
used = skb->len - offset;
|
|
if (len < used)
|
|
used = len;
|
|
|
|
/* Do we have urgent data here? */
|
|
if (tp->urg_data) {
|
|
u32 urg_offset = tp->urg_seq - *seq;
|
|
if (urg_offset < used) {
|
|
if (!urg_offset) {
|
|
if (!sock_flag(sk, SOCK_URGINLINE)) {
|
|
++*seq;
|
|
urg_hole++;
|
|
offset++;
|
|
used--;
|
|
if (!used)
|
|
goto skip_copy;
|
|
}
|
|
} else
|
|
used = urg_offset;
|
|
}
|
|
}
|
|
|
|
if (!(flags & MSG_TRUNC)) {
|
|
err = skb_copy_datagram_msg(skb, offset, msg, used);
|
|
if (err) {
|
|
/* Exception. Bailout! */
|
|
if (!copied)
|
|
copied = -EFAULT;
|
|
break;
|
|
}
|
|
}
|
|
|
|
*seq += used;
|
|
copied += used;
|
|
len -= used;
|
|
|
|
tcp_rcv_space_adjust(sk);
|
|
|
|
skip_copy:
|
|
if (tp->urg_data && after(tp->copied_seq, tp->urg_seq))
|
|
tp->urg_data = 0;
|
|
if (used + offset < skb->len)
|
|
continue;
|
|
|
|
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
|
|
goto found_fin_ok;
|
|
if (!(flags & MSG_PEEK))
|
|
sk_eat_skb(sk, skb);
|
|
continue;
|
|
|
|
found_fin_ok:
|
|
/* Process the FIN. */
|
|
++*seq;
|
|
if (!(flags & MSG_PEEK))
|
|
sk_eat_skb(sk, skb);
|
|
break;
|
|
} while (len > 0);
|
|
|
|
/* According to UNIX98, msg_name/msg_namelen are ignored
|
|
* on connected socket. I was just happy when found this 8) --ANK
|
|
*/
|
|
|
|
/* Clean up data we have read: This will do ACK frames. */
|
|
tcp_cleanup_rbuf(sk, copied);
|
|
|
|
release_sock(sk);
|
|
return copied;
|
|
|
|
out:
|
|
release_sock(sk);
|
|
return err;
|
|
|
|
recv_urg:
|
|
err = tcp_recv_urg(sk, msg, len, flags);
|
|
goto out;
|
|
|
|
recv_sndq:
|
|
err = tcp_peek_sndq(sk, msg, len);
|
|
goto out;
|
|
}
|
|
EXPORT_SYMBOL(tcp_recvmsg);
|
|
|
|
void tcp_set_state(struct sock *sk, int state)
|
|
{
|
|
int oldstate = sk->sk_state;
|
|
|
|
switch (state) {
|
|
case TCP_ESTABLISHED:
|
|
if (oldstate != TCP_ESTABLISHED)
|
|
TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB);
|
|
break;
|
|
|
|
case TCP_CLOSE:
|
|
if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED)
|
|
TCP_INC_STATS(sock_net(sk), TCP_MIB_ESTABRESETS);
|
|
|
|
sk->sk_prot->unhash(sk);
|
|
if (inet_csk(sk)->icsk_bind_hash &&
|
|
!(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
|
|
inet_put_port(sk);
|
|
/* fall through */
|
|
default:
|
|
if (oldstate == TCP_ESTABLISHED)
|
|
TCP_DEC_STATS(sock_net(sk), TCP_MIB_CURRESTAB);
|
|
}
|
|
|
|
/* Change state AFTER socket is unhashed to avoid closed
|
|
* socket sitting in hash tables.
|
|
*/
|
|
sk_state_store(sk, state);
|
|
|
|
#ifdef STATE_TRACE
|
|
SOCK_DEBUG(sk, "TCP sk=%p, State %s -> %s\n", sk, statename[oldstate], statename[state]);
|
|
#endif
|
|
}
|
|
EXPORT_SYMBOL_GPL(tcp_set_state);
|
|
|
|
/*
|
|
* State processing on a close. This implements the state shift for
|
|
* sending our FIN frame. Note that we only send a FIN for some
|
|
* states. A shutdown() may have already sent the FIN, or we may be
|
|
* closed.
|
|
*/
|
|
|
|
static const unsigned char new_state[16] = {
|
|
/* current state: new state: action: */
|
|
[0 /* (Invalid) */] = TCP_CLOSE,
|
|
[TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
|
|
[TCP_SYN_SENT] = TCP_CLOSE,
|
|
[TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
|
|
[TCP_FIN_WAIT1] = TCP_FIN_WAIT1,
|
|
[TCP_FIN_WAIT2] = TCP_FIN_WAIT2,
|
|
[TCP_TIME_WAIT] = TCP_CLOSE,
|
|
[TCP_CLOSE] = TCP_CLOSE,
|
|
[TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN,
|
|
[TCP_LAST_ACK] = TCP_LAST_ACK,
|
|
[TCP_LISTEN] = TCP_CLOSE,
|
|
[TCP_CLOSING] = TCP_CLOSING,
|
|
[TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */
|
|
};
|
|
|
|
static int tcp_close_state(struct sock *sk)
|
|
{
|
|
int next = (int)new_state[sk->sk_state];
|
|
int ns = next & TCP_STATE_MASK;
|
|
|
|
tcp_set_state(sk, ns);
|
|
|
|
return next & TCP_ACTION_FIN;
|
|
}
|
|
|
|
/*
|
|
* Shutdown the sending side of a connection. Much like close except
|
|
* that we don't receive shut down or sock_set_flag(sk, SOCK_DEAD).
|
|
*/
|
|
|
|
void tcp_shutdown(struct sock *sk, int how)
|
|
{
|
|
/* We need to grab some memory, and put together a FIN,
|
|
* and then put it into the queue to be sent.
|
|
* Tim MacKenzie(tym@dibbler.cs.monash.edu.au) 4 Dec '92.
|
|
*/
|
|
if (!(how & SEND_SHUTDOWN))
|
|
return;
|
|
|
|
/* If we've already sent a FIN, or it's a closed state, skip this. */
|
|
if ((1 << sk->sk_state) &
|
|
(TCPF_ESTABLISHED | TCPF_SYN_SENT |
|
|
TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) {
|
|
/* Clear out any half completed packets. FIN if needed. */
|
|
if (tcp_close_state(sk))
|
|
tcp_send_fin(sk);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(tcp_shutdown);
|
|
|
|
bool tcp_check_oom(struct sock *sk, int shift)
|
|
{
|
|
bool too_many_orphans, out_of_socket_memory;
|
|
|
|
too_many_orphans = tcp_too_many_orphans(sk, shift);
|
|
out_of_socket_memory = tcp_out_of_memory(sk);
|
|
|
|
if (too_many_orphans)
|
|
net_info_ratelimited("too many orphaned sockets\n");
|
|
if (out_of_socket_memory)
|
|
net_info_ratelimited("out of memory -- consider tuning tcp_mem\n");
|
|
return too_many_orphans || out_of_socket_memory;
|
|
}
|
|
|
|
void tcp_close(struct sock *sk, long timeout)
|
|
{
|
|
struct sk_buff *skb;
|
|
int data_was_unread = 0;
|
|
int state;
|
|
|
|
lock_sock(sk);
|
|
sk->sk_shutdown = SHUTDOWN_MASK;
|
|
|
|
if (sk->sk_state == TCP_LISTEN) {
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
|
|
/* Special case. */
|
|
inet_csk_listen_stop(sk);
|
|
|
|
goto adjudge_to_death;
|
|
}
|
|
|
|
/* We need to flush the recv. buffs. We do this only on the
|
|
* descriptor close, not protocol-sourced closes, because the
|
|
* reader process may not have drained the data yet!
|
|
*/
|
|
while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
|
|
u32 len = TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq;
|
|
|
|
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
|
|
len--;
|
|
data_was_unread += len;
|
|
__kfree_skb(skb);
|
|
}
|
|
|
|
sk_mem_reclaim(sk);
|
|
|
|
/* If socket has been already reset (e.g. in tcp_reset()) - kill it. */
|
|
if (sk->sk_state == TCP_CLOSE)
|
|
goto adjudge_to_death;
|
|
|
|
/* As outlined in RFC 2525, section 2.17, we send a RST here because
|
|
* data was lost. To witness the awful effects of the old behavior of
|
|
* always doing a FIN, run an older 2.1.x kernel or 2.0.x, start a bulk
|
|
* GET in an FTP client, suspend the process, wait for the client to
|
|
* advertise a zero window, then kill -9 the FTP client, wheee...
|
|
* Note: timeout is always zero in such a case.
|
|
*/
|
|
if (unlikely(tcp_sk(sk)->repair)) {
|
|
sk->sk_prot->disconnect(sk, 0);
|
|
} else if (data_was_unread) {
|
|
/* Unread data was tossed, zap the connection. */
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE);
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
tcp_send_active_reset(sk, sk->sk_allocation);
|
|
} else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
|
|
/* Check zero linger _after_ checking for unread data. */
|
|
sk->sk_prot->disconnect(sk, 0);
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
|
|
} else if (tcp_close_state(sk)) {
|
|
/* We FIN if the application ate all the data before
|
|
* zapping the connection.
|
|
*/
|
|
|
|
/* RED-PEN. Formally speaking, we have broken TCP state
|
|
* machine. State transitions:
|
|
*
|
|
* TCP_ESTABLISHED -> TCP_FIN_WAIT1
|
|
* TCP_SYN_RECV -> TCP_FIN_WAIT1 (forget it, it's impossible)
|
|
* TCP_CLOSE_WAIT -> TCP_LAST_ACK
|
|
*
|
|
* are legal only when FIN has been sent (i.e. in window),
|
|
* rather than queued out of window. Purists blame.
|
|
*
|
|
* F.e. "RFC state" is ESTABLISHED,
|
|
* if Linux state is FIN-WAIT-1, but FIN is still not sent.
|
|
*
|
|
* The visible declinations are that sometimes
|
|
* we enter time-wait state, when it is not required really
|
|
* (harmless), do not send active resets, when they are
|
|
* required by specs (TCP_ESTABLISHED, TCP_CLOSE_WAIT, when
|
|
* they look as CLOSING or LAST_ACK for Linux)
|
|
* Probably, I missed some more holelets.
|
|
* --ANK
|
|
* XXX (TFO) - To start off we don't support SYN+ACK+FIN
|
|
* in a single packet! (May consider it later but will
|
|
* probably need API support or TCP_CORK SYN-ACK until
|
|
* data is written and socket is closed.)
|
|
*/
|
|
tcp_send_fin(sk);
|
|
}
|
|
|
|
sk_stream_wait_close(sk, timeout);
|
|
|
|
adjudge_to_death:
|
|
state = sk->sk_state;
|
|
sock_hold(sk);
|
|
sock_orphan(sk);
|
|
|
|
/* It is the last release_sock in its life. It will remove backlog. */
|
|
release_sock(sk);
|
|
|
|
|
|
/* Now socket is owned by kernel and we acquire BH lock
|
|
* to finish close. No need to check for user refs.
|
|
*/
|
|
local_bh_disable();
|
|
bh_lock_sock(sk);
|
|
WARN_ON(sock_owned_by_user(sk));
|
|
|
|
percpu_counter_inc(sk->sk_prot->orphan_count);
|
|
|
|
/* Have we already been destroyed by a softirq or backlog? */
|
|
if (state != TCP_CLOSE && sk->sk_state == TCP_CLOSE)
|
|
goto out;
|
|
|
|
/* This is a (useful) BSD violating of the RFC. There is a
|
|
* problem with TCP as specified in that the other end could
|
|
* keep a socket open forever with no application left this end.
|
|
* We use a 1 minute timeout (about the same as BSD) then kill
|
|
* our end. If they send after that then tough - BUT: long enough
|
|
* that we won't make the old 4*rto = almost no time - whoops
|
|
* reset mistake.
|
|
*
|
|
* Nope, it was not mistake. It is really desired behaviour
|
|
* f.e. on http servers, when such sockets are useless, but
|
|
* consume significant resources. Let's do it with special
|
|
* linger2 option. --ANK
|
|
*/
|
|
|
|
if (sk->sk_state == TCP_FIN_WAIT2) {
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
if (tp->linger2 < 0) {
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
tcp_send_active_reset(sk, GFP_ATOMIC);
|
|
__NET_INC_STATS(sock_net(sk),
|
|
LINUX_MIB_TCPABORTONLINGER);
|
|
} else {
|
|
const int tmo = tcp_fin_time(sk);
|
|
|
|
if (tmo > TCP_TIMEWAIT_LEN) {
|
|
inet_csk_reset_keepalive_timer(sk,
|
|
tmo - TCP_TIMEWAIT_LEN);
|
|
} else {
|
|
tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
if (sk->sk_state != TCP_CLOSE) {
|
|
sk_mem_reclaim(sk);
|
|
if (tcp_check_oom(sk, 0)) {
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
tcp_send_active_reset(sk, GFP_ATOMIC);
|
|
__NET_INC_STATS(sock_net(sk),
|
|
LINUX_MIB_TCPABORTONMEMORY);
|
|
}
|
|
}
|
|
|
|
if (sk->sk_state == TCP_CLOSE) {
|
|
struct request_sock *req = tcp_sk(sk)->fastopen_rsk;
|
|
/* We could get here with a non-NULL req if the socket is
|
|
* aborted (e.g., closed with unread data) before 3WHS
|
|
* finishes.
|
|
*/
|
|
if (req)
|
|
reqsk_fastopen_remove(sk, req, false);
|
|
inet_csk_destroy_sock(sk);
|
|
}
|
|
/* Otherwise, socket is reprieved until protocol close. */
|
|
|
|
out:
|
|
bh_unlock_sock(sk);
|
|
local_bh_enable();
|
|
sock_put(sk);
|
|
}
|
|
EXPORT_SYMBOL(tcp_close);
|
|
|
|
/* These states need RST on ABORT according to RFC793 */
|
|
|
|
static inline bool tcp_need_reset(int state)
|
|
{
|
|
return (1 << state) &
|
|
(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 |
|
|
TCPF_FIN_WAIT2 | TCPF_SYN_RECV);
|
|
}
|
|
|
|
int tcp_disconnect(struct sock *sk, int flags)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct inet_connection_sock *icsk = inet_csk(sk);
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
int err = 0;
|
|
int old_state = sk->sk_state;
|
|
|
|
if (old_state != TCP_CLOSE)
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
|
|
/* ABORT function of RFC793 */
|
|
if (old_state == TCP_LISTEN) {
|
|
inet_csk_listen_stop(sk);
|
|
} else if (unlikely(tp->repair)) {
|
|
sk->sk_err = ECONNABORTED;
|
|
} else if (tcp_need_reset(old_state) ||
|
|
(tp->snd_nxt != tp->write_seq &&
|
|
(1 << old_state) & (TCPF_CLOSING | TCPF_LAST_ACK))) {
|
|
/* The last check adjusts for discrepancy of Linux wrt. RFC
|
|
* states
|
|
*/
|
|
tcp_send_active_reset(sk, gfp_any());
|
|
sk->sk_err = ECONNRESET;
|
|
} else if (old_state == TCP_SYN_SENT)
|
|
sk->sk_err = ECONNRESET;
|
|
|
|
tcp_clear_xmit_timers(sk);
|
|
__skb_queue_purge(&sk->sk_receive_queue);
|
|
tcp_write_queue_purge(sk);
|
|
tcp_fastopen_active_disable_ofo_check(sk);
|
|
skb_rbtree_purge(&tp->out_of_order_queue);
|
|
|
|
inet->inet_dport = 0;
|
|
|
|
if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
|
|
inet_reset_saddr(sk);
|
|
|
|
sk->sk_shutdown = 0;
|
|
sock_reset_flag(sk, SOCK_DONE);
|
|
tp->srtt_us = 0;
|
|
tp->write_seq += tp->max_window + 2;
|
|
if (tp->write_seq == 0)
|
|
tp->write_seq = 1;
|
|
icsk->icsk_backoff = 0;
|
|
tp->snd_cwnd = 2;
|
|
icsk->icsk_probes_out = 0;
|
|
tp->packets_out = 0;
|
|
tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
|
|
tp->snd_cwnd_cnt = 0;
|
|
tp->window_clamp = 0;
|
|
tcp_set_ca_state(sk, TCP_CA_Open);
|
|
tcp_clear_retrans(tp);
|
|
inet_csk_delack_init(sk);
|
|
/* Initialize rcv_mss to TCP_MIN_MSS to avoid division by 0
|
|
* issue in __tcp_select_window()
|
|
*/
|
|
icsk->icsk_ack.rcv_mss = TCP_MIN_MSS;
|
|
tcp_init_send_head(sk);
|
|
memset(&tp->rx_opt, 0, sizeof(tp->rx_opt));
|
|
__sk_dst_reset(sk);
|
|
dst_release(sk->sk_rx_dst);
|
|
sk->sk_rx_dst = NULL;
|
|
tcp_saved_syn_free(tp);
|
|
|
|
/* Clean up fastopen related fields */
|
|
tcp_free_fastopen_req(tp);
|
|
inet->defer_connect = 0;
|
|
|
|
WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
|
|
|
|
sk->sk_error_report(sk);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(tcp_disconnect);
|
|
|
|
static inline bool tcp_can_repair_sock(const struct sock *sk)
|
|
{
|
|
return ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) &&
|
|
(sk->sk_state != TCP_LISTEN);
|
|
}
|
|
|
|
static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int len)
|
|
{
|
|
struct tcp_repair_window opt;
|
|
|
|
if (!tp->repair)
|
|
return -EPERM;
|
|
|
|
if (len != sizeof(opt))
|
|
return -EINVAL;
|
|
|
|
if (copy_from_user(&opt, optbuf, sizeof(opt)))
|
|
return -EFAULT;
|
|
|
|
if (opt.max_window < opt.snd_wnd)
|
|
return -EINVAL;
|
|
|
|
if (after(opt.snd_wl1, tp->rcv_nxt + opt.rcv_wnd))
|
|
return -EINVAL;
|
|
|
|
if (after(opt.rcv_wup, tp->rcv_nxt))
|
|
return -EINVAL;
|
|
|
|
tp->snd_wl1 = opt.snd_wl1;
|
|
tp->snd_wnd = opt.snd_wnd;
|
|
tp->max_window = opt.max_window;
|
|
|
|
tp->rcv_wnd = opt.rcv_wnd;
|
|
tp->rcv_wup = opt.rcv_wup;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int tcp_repair_options_est(struct sock *sk,
|
|
struct tcp_repair_opt __user *optbuf, unsigned int len)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct tcp_repair_opt opt;
|
|
|
|
while (len >= sizeof(opt)) {
|
|
if (copy_from_user(&opt, optbuf, sizeof(opt)))
|
|
return -EFAULT;
|
|
|
|
optbuf++;
|
|
len -= sizeof(opt);
|
|
|
|
switch (opt.opt_code) {
|
|
case TCPOPT_MSS:
|
|
tp->rx_opt.mss_clamp = opt.opt_val;
|
|
tcp_mtup_init(sk);
|
|
break;
|
|
case TCPOPT_WINDOW:
|
|
{
|
|
u16 snd_wscale = opt.opt_val & 0xFFFF;
|
|
u16 rcv_wscale = opt.opt_val >> 16;
|
|
|
|
if (snd_wscale > TCP_MAX_WSCALE || rcv_wscale > TCP_MAX_WSCALE)
|
|
return -EFBIG;
|
|
|
|
tp->rx_opt.snd_wscale = snd_wscale;
|
|
tp->rx_opt.rcv_wscale = rcv_wscale;
|
|
tp->rx_opt.wscale_ok = 1;
|
|
}
|
|
break;
|
|
case TCPOPT_SACK_PERM:
|
|
if (opt.opt_val != 0)
|
|
return -EINVAL;
|
|
|
|
tp->rx_opt.sack_ok |= TCP_SACK_SEEN;
|
|
if (sysctl_tcp_fack)
|
|
tcp_enable_fack(tp);
|
|
break;
|
|
case TCPOPT_TIMESTAMP:
|
|
if (opt.opt_val != 0)
|
|
return -EINVAL;
|
|
|
|
tp->rx_opt.tstamp_ok = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Socket option code for TCP.
|
|
*/
|
|
static int do_tcp_setsockopt(struct sock *sk, int level,
|
|
int optname, char __user *optval, unsigned int optlen)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct inet_connection_sock *icsk = inet_csk(sk);
|
|
struct net *net = sock_net(sk);
|
|
int val;
|
|
int err = 0;
|
|
|
|
/* These are data/string values, all the others are ints */
|
|
switch (optname) {
|
|
case TCP_CONGESTION: {
|
|
char name[TCP_CA_NAME_MAX];
|
|
|
|
if (optlen < 1)
|
|
return -EINVAL;
|
|
|
|
val = strncpy_from_user(name, optval,
|
|
min_t(long, TCP_CA_NAME_MAX-1, optlen));
|
|
if (val < 0)
|
|
return -EFAULT;
|
|
name[val] = 0;
|
|
|
|
lock_sock(sk);
|
|
err = tcp_set_congestion_control(sk, name, true);
|
|
release_sock(sk);
|
|
return err;
|
|
}
|
|
case TCP_ULP: {
|
|
char name[TCP_ULP_NAME_MAX];
|
|
|
|
if (optlen < 1)
|
|
return -EINVAL;
|
|
|
|
val = strncpy_from_user(name, optval,
|
|
min_t(long, TCP_ULP_NAME_MAX - 1,
|
|
optlen));
|
|
if (val < 0)
|
|
return -EFAULT;
|
|
name[val] = 0;
|
|
|
|
lock_sock(sk);
|
|
err = tcp_set_ulp(sk, name);
|
|
release_sock(sk);
|
|
return err;
|
|
}
|
|
default:
|
|
/* fallthru */
|
|
break;
|
|
}
|
|
|
|
if (optlen < sizeof(int))
|
|
return -EINVAL;
|
|
|
|
if (get_user(val, (int __user *)optval))
|
|
return -EFAULT;
|
|
|
|
lock_sock(sk);
|
|
|
|
switch (optname) {
|
|
case TCP_MAXSEG:
|
|
/* Values greater than interface MTU won't take effect. However
|
|
* at the point when this call is done we typically don't yet
|
|
* know which interface is going to be used
|
|
*/
|
|
if (val && (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW)) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
tp->rx_opt.user_mss = val;
|
|
break;
|
|
|
|
case TCP_NODELAY:
|
|
if (val) {
|
|
/* TCP_NODELAY is weaker than TCP_CORK, so that
|
|
* this option on corked socket is remembered, but
|
|
* it is not activated until cork is cleared.
|
|
*
|
|
* However, when TCP_NODELAY is set we make
|
|
* an explicit push, which overrides even TCP_CORK
|
|
* for currently queued segments.
|
|
*/
|
|
tp->nonagle |= TCP_NAGLE_OFF|TCP_NAGLE_PUSH;
|
|
tcp_push_pending_frames(sk);
|
|
} else {
|
|
tp->nonagle &= ~TCP_NAGLE_OFF;
|
|
}
|
|
break;
|
|
|
|
case TCP_THIN_LINEAR_TIMEOUTS:
|
|
if (val < 0 || val > 1)
|
|
err = -EINVAL;
|
|
else
|
|
tp->thin_lto = val;
|
|
break;
|
|
|
|
case TCP_THIN_DUPACK:
|
|
if (val < 0 || val > 1)
|
|
err = -EINVAL;
|
|
break;
|
|
|
|
case TCP_REPAIR:
|
|
if (!tcp_can_repair_sock(sk))
|
|
err = -EPERM;
|
|
else if (val == 1) {
|
|
tp->repair = 1;
|
|
sk->sk_reuse = SK_FORCE_REUSE;
|
|
tp->repair_queue = TCP_NO_QUEUE;
|
|
} else if (val == 0) {
|
|
tp->repair = 0;
|
|
sk->sk_reuse = SK_NO_REUSE;
|
|
tcp_send_window_probe(sk);
|
|
} else
|
|
err = -EINVAL;
|
|
|
|
break;
|
|
|
|
case TCP_REPAIR_QUEUE:
|
|
if (!tp->repair)
|
|
err = -EPERM;
|
|
else if (val < TCP_QUEUES_NR)
|
|
tp->repair_queue = val;
|
|
else
|
|
err = -EINVAL;
|
|
break;
|
|
|
|
case TCP_QUEUE_SEQ:
|
|
if (sk->sk_state != TCP_CLOSE)
|
|
err = -EPERM;
|
|
else if (tp->repair_queue == TCP_SEND_QUEUE)
|
|
tp->write_seq = val;
|
|
else if (tp->repair_queue == TCP_RECV_QUEUE)
|
|
tp->rcv_nxt = val;
|
|
else
|
|
err = -EINVAL;
|
|
break;
|
|
|
|
case TCP_REPAIR_OPTIONS:
|
|
if (!tp->repair)
|
|
err = -EINVAL;
|
|
else if (sk->sk_state == TCP_ESTABLISHED)
|
|
err = tcp_repair_options_est(sk,
|
|
(struct tcp_repair_opt __user *)optval,
|
|
optlen);
|
|
else
|
|
err = -EPERM;
|
|
break;
|
|
|
|
case TCP_CORK:
|
|
/* When set indicates to always queue non-full frames.
|
|
* Later the user clears this option and we transmit
|
|
* any pending partial frames in the queue. This is
|
|
* meant to be used alongside sendfile() to get properly
|
|
* filled frames when the user (for example) must write
|
|
* out headers with a write() call first and then use
|
|
* sendfile to send out the data parts.
|
|
*
|
|
* TCP_CORK can be set together with TCP_NODELAY and it is
|
|
* stronger than TCP_NODELAY.
|
|
*/
|
|
if (val) {
|
|
tp->nonagle |= TCP_NAGLE_CORK;
|
|
} else {
|
|
tp->nonagle &= ~TCP_NAGLE_CORK;
|
|
if (tp->nonagle&TCP_NAGLE_OFF)
|
|
tp->nonagle |= TCP_NAGLE_PUSH;
|
|
tcp_push_pending_frames(sk);
|
|
}
|
|
break;
|
|
|
|
case TCP_KEEPIDLE:
|
|
if (val < 1 || val > MAX_TCP_KEEPIDLE)
|
|
err = -EINVAL;
|
|
else {
|
|
tp->keepalive_time = val * HZ;
|
|
if (sock_flag(sk, SOCK_KEEPOPEN) &&
|
|
!((1 << sk->sk_state) &
|
|
(TCPF_CLOSE | TCPF_LISTEN))) {
|
|
u32 elapsed = keepalive_time_elapsed(tp);
|
|
if (tp->keepalive_time > elapsed)
|
|
elapsed = tp->keepalive_time - elapsed;
|
|
else
|
|
elapsed = 0;
|
|
inet_csk_reset_keepalive_timer(sk, elapsed);
|
|
}
|
|
}
|
|
break;
|
|
case TCP_KEEPINTVL:
|
|
if (val < 1 || val > MAX_TCP_KEEPINTVL)
|
|
err = -EINVAL;
|
|
else
|
|
tp->keepalive_intvl = val * HZ;
|
|
break;
|
|
case TCP_KEEPCNT:
|
|
if (val < 1 || val > MAX_TCP_KEEPCNT)
|
|
err = -EINVAL;
|
|
else
|
|
tp->keepalive_probes = val;
|
|
break;
|
|
case TCP_SYNCNT:
|
|
if (val < 1 || val > MAX_TCP_SYNCNT)
|
|
err = -EINVAL;
|
|
else
|
|
icsk->icsk_syn_retries = val;
|
|
break;
|
|
|
|
case TCP_SAVE_SYN:
|
|
if (val < 0 || val > 1)
|
|
err = -EINVAL;
|
|
else
|
|
tp->save_syn = val;
|
|
break;
|
|
|
|
case TCP_LINGER2:
|
|
if (val < 0)
|
|
tp->linger2 = -1;
|
|
else if (val > net->ipv4.sysctl_tcp_fin_timeout / HZ)
|
|
tp->linger2 = 0;
|
|
else
|
|
tp->linger2 = val * HZ;
|
|
break;
|
|
|
|
case TCP_DEFER_ACCEPT:
|
|
/* Translate value in seconds to number of retransmits */
|
|
icsk->icsk_accept_queue.rskq_defer_accept =
|
|
secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ,
|
|
TCP_RTO_MAX / HZ);
|
|
break;
|
|
|
|
case TCP_WINDOW_CLAMP:
|
|
if (!val) {
|
|
if (sk->sk_state != TCP_CLOSE) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
tp->window_clamp = 0;
|
|
} else
|
|
tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ?
|
|
SOCK_MIN_RCVBUF / 2 : val;
|
|
break;
|
|
|
|
case TCP_QUICKACK:
|
|
if (!val) {
|
|
icsk->icsk_ack.pingpong = 1;
|
|
} else {
|
|
icsk->icsk_ack.pingpong = 0;
|
|
if ((1 << sk->sk_state) &
|
|
(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) &&
|
|
inet_csk_ack_scheduled(sk)) {
|
|
icsk->icsk_ack.pending |= ICSK_ACK_PUSHED;
|
|
tcp_cleanup_rbuf(sk, 1);
|
|
if (!(val & 1))
|
|
icsk->icsk_ack.pingpong = 1;
|
|
}
|
|
}
|
|
break;
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
case TCP_MD5SIG:
|
|
case TCP_MD5SIG_EXT:
|
|
/* Read the IP->Key mappings from userspace */
|
|
err = tp->af_specific->md5_parse(sk, optname, optval, optlen);
|
|
break;
|
|
#endif
|
|
case TCP_USER_TIMEOUT:
|
|
/* Cap the max time in ms TCP will retry or probe the window
|
|
* before giving up and aborting (ETIMEDOUT) a connection.
|
|
*/
|
|
if (val < 0)
|
|
err = -EINVAL;
|
|
else
|
|
icsk->icsk_user_timeout = msecs_to_jiffies(val);
|
|
break;
|
|
|
|
case TCP_FASTOPEN:
|
|
if (val >= 0 && ((1 << sk->sk_state) & (TCPF_CLOSE |
|
|
TCPF_LISTEN))) {
|
|
tcp_fastopen_init_key_once(true);
|
|
|
|
fastopen_queue_tune(sk, val);
|
|
} else {
|
|
err = -EINVAL;
|
|
}
|
|
break;
|
|
case TCP_FASTOPEN_CONNECT:
|
|
if (val > 1 || val < 0) {
|
|
err = -EINVAL;
|
|
} else if (sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) {
|
|
if (sk->sk_state == TCP_CLOSE)
|
|
tp->fastopen_connect = val;
|
|
else
|
|
err = -EINVAL;
|
|
} else {
|
|
err = -EOPNOTSUPP;
|
|
}
|
|
break;
|
|
case TCP_TIMESTAMP:
|
|
if (!tp->repair)
|
|
err = -EPERM;
|
|
else
|
|
tp->tsoffset = val - tcp_time_stamp_raw();
|
|
break;
|
|
case TCP_REPAIR_WINDOW:
|
|
err = tcp_repair_set_window(tp, optval, optlen);
|
|
break;
|
|
case TCP_NOTSENT_LOWAT:
|
|
tp->notsent_lowat = val;
|
|
sk->sk_write_space(sk);
|
|
break;
|
|
default:
|
|
err = -ENOPROTOOPT;
|
|
break;
|
|
}
|
|
|
|
release_sock(sk);
|
|
return err;
|
|
}
|
|
|
|
int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
|
|
unsigned int optlen)
|
|
{
|
|
const struct inet_connection_sock *icsk = inet_csk(sk);
|
|
|
|
if (level != SOL_TCP)
|
|
return icsk->icsk_af_ops->setsockopt(sk, level, optname,
|
|
optval, optlen);
|
|
return do_tcp_setsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
EXPORT_SYMBOL(tcp_setsockopt);
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
int compat_tcp_setsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, unsigned int optlen)
|
|
{
|
|
if (level != SOL_TCP)
|
|
return inet_csk_compat_setsockopt(sk, level, optname,
|
|
optval, optlen);
|
|
return do_tcp_setsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
EXPORT_SYMBOL(compat_tcp_setsockopt);
|
|
#endif
|
|
|
|
static void tcp_get_info_chrono_stats(const struct tcp_sock *tp,
|
|
struct tcp_info *info)
|
|
{
|
|
u64 stats[__TCP_CHRONO_MAX], total = 0;
|
|
enum tcp_chrono i;
|
|
|
|
for (i = TCP_CHRONO_BUSY; i < __TCP_CHRONO_MAX; ++i) {
|
|
stats[i] = tp->chrono_stat[i - 1];
|
|
if (i == tp->chrono_type)
|
|
stats[i] += tcp_jiffies32 - tp->chrono_start;
|
|
stats[i] *= USEC_PER_SEC / HZ;
|
|
total += stats[i];
|
|
}
|
|
|
|
info->tcpi_busy_time = total;
|
|
info->tcpi_rwnd_limited = stats[TCP_CHRONO_RWND_LIMITED];
|
|
info->tcpi_sndbuf_limited = stats[TCP_CHRONO_SNDBUF_LIMITED];
|
|
}
|
|
|
|
/* Return information about state of tcp endpoint in API format. */
|
|
void tcp_get_info(struct sock *sk, struct tcp_info *info)
|
|
{
|
|
const struct tcp_sock *tp = tcp_sk(sk); /* iff sk_type == SOCK_STREAM */
|
|
const struct inet_connection_sock *icsk = inet_csk(sk);
|
|
u32 now;
|
|
u64 rate64;
|
|
bool slow;
|
|
u32 rate;
|
|
|
|
memset(info, 0, sizeof(*info));
|
|
if (sk->sk_type != SOCK_STREAM)
|
|
return;
|
|
|
|
info->tcpi_state = sk_state_load(sk);
|
|
|
|
/* Report meaningful fields for all TCP states, including listeners */
|
|
rate = READ_ONCE(sk->sk_pacing_rate);
|
|
rate64 = rate != ~0U ? rate : ~0ULL;
|
|
info->tcpi_pacing_rate = rate64;
|
|
|
|
rate = READ_ONCE(sk->sk_max_pacing_rate);
|
|
rate64 = rate != ~0U ? rate : ~0ULL;
|
|
info->tcpi_max_pacing_rate = rate64;
|
|
|
|
info->tcpi_reordering = tp->reordering;
|
|
info->tcpi_snd_cwnd = tp->snd_cwnd;
|
|
|
|
if (info->tcpi_state == TCP_LISTEN) {
|
|
/* listeners aliased fields :
|
|
* tcpi_unacked -> Number of children ready for accept()
|
|
* tcpi_sacked -> max backlog
|
|
*/
|
|
info->tcpi_unacked = sk->sk_ack_backlog;
|
|
info->tcpi_sacked = sk->sk_max_ack_backlog;
|
|
return;
|
|
}
|
|
|
|
slow = lock_sock_fast(sk);
|
|
|
|
info->tcpi_ca_state = icsk->icsk_ca_state;
|
|
info->tcpi_retransmits = icsk->icsk_retransmits;
|
|
info->tcpi_probes = icsk->icsk_probes_out;
|
|
info->tcpi_backoff = icsk->icsk_backoff;
|
|
|
|
if (tp->rx_opt.tstamp_ok)
|
|
info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
|
|
if (tcp_is_sack(tp))
|
|
info->tcpi_options |= TCPI_OPT_SACK;
|
|
if (tp->rx_opt.wscale_ok) {
|
|
info->tcpi_options |= TCPI_OPT_WSCALE;
|
|
info->tcpi_snd_wscale = tp->rx_opt.snd_wscale;
|
|
info->tcpi_rcv_wscale = tp->rx_opt.rcv_wscale;
|
|
}
|
|
|
|
if (tp->ecn_flags & TCP_ECN_OK)
|
|
info->tcpi_options |= TCPI_OPT_ECN;
|
|
if (tp->ecn_flags & TCP_ECN_SEEN)
|
|
info->tcpi_options |= TCPI_OPT_ECN_SEEN;
|
|
if (tp->syn_data_acked)
|
|
info->tcpi_options |= TCPI_OPT_SYN_DATA;
|
|
|
|
info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto);
|
|
info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato);
|
|
info->tcpi_snd_mss = tp->mss_cache;
|
|
info->tcpi_rcv_mss = icsk->icsk_ack.rcv_mss;
|
|
|
|
info->tcpi_unacked = tp->packets_out;
|
|
info->tcpi_sacked = tp->sacked_out;
|
|
|
|
info->tcpi_lost = tp->lost_out;
|
|
info->tcpi_retrans = tp->retrans_out;
|
|
info->tcpi_fackets = tp->fackets_out;
|
|
|
|
now = tcp_jiffies32;
|
|
info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime);
|
|
info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime);
|
|
info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp);
|
|
|
|
info->tcpi_pmtu = icsk->icsk_pmtu_cookie;
|
|
info->tcpi_rcv_ssthresh = tp->rcv_ssthresh;
|
|
info->tcpi_rtt = tp->srtt_us >> 3;
|
|
info->tcpi_rttvar = tp->mdev_us >> 2;
|
|
info->tcpi_snd_ssthresh = tp->snd_ssthresh;
|
|
info->tcpi_advmss = tp->advmss;
|
|
|
|
info->tcpi_rcv_rtt = tp->rcv_rtt_est.rtt_us >> 3;
|
|
info->tcpi_rcv_space = tp->rcvq_space.space;
|
|
|
|
info->tcpi_total_retrans = tp->total_retrans;
|
|
|
|
info->tcpi_bytes_acked = tp->bytes_acked;
|
|
info->tcpi_bytes_received = tp->bytes_received;
|
|
info->tcpi_notsent_bytes = max_t(int, 0, tp->write_seq - tp->snd_nxt);
|
|
tcp_get_info_chrono_stats(tp, info);
|
|
|
|
info->tcpi_segs_out = tp->segs_out;
|
|
info->tcpi_segs_in = tp->segs_in;
|
|
|
|
info->tcpi_min_rtt = tcp_min_rtt(tp);
|
|
info->tcpi_data_segs_in = tp->data_segs_in;
|
|
info->tcpi_data_segs_out = tp->data_segs_out;
|
|
|
|
info->tcpi_delivery_rate_app_limited = tp->rate_app_limited ? 1 : 0;
|
|
rate64 = tcp_compute_delivery_rate(tp);
|
|
if (rate64)
|
|
info->tcpi_delivery_rate = rate64;
|
|
unlock_sock_fast(sk, slow);
|
|
}
|
|
EXPORT_SYMBOL_GPL(tcp_get_info);
|
|
|
|
struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk)
|
|
{
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
struct sk_buff *stats;
|
|
struct tcp_info info;
|
|
u64 rate64;
|
|
u32 rate;
|
|
|
|
stats = alloc_skb(7 * nla_total_size_64bit(sizeof(u64)) +
|
|
3 * nla_total_size(sizeof(u32)) +
|
|
2 * nla_total_size(sizeof(u8)), GFP_ATOMIC);
|
|
if (!stats)
|
|
return NULL;
|
|
|
|
tcp_get_info_chrono_stats(tp, &info);
|
|
nla_put_u64_64bit(stats, TCP_NLA_BUSY,
|
|
info.tcpi_busy_time, TCP_NLA_PAD);
|
|
nla_put_u64_64bit(stats, TCP_NLA_RWND_LIMITED,
|
|
info.tcpi_rwnd_limited, TCP_NLA_PAD);
|
|
nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED,
|
|
info.tcpi_sndbuf_limited, TCP_NLA_PAD);
|
|
nla_put_u64_64bit(stats, TCP_NLA_DATA_SEGS_OUT,
|
|
tp->data_segs_out, TCP_NLA_PAD);
|
|
nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS,
|
|
tp->total_retrans, TCP_NLA_PAD);
|
|
|
|
rate = READ_ONCE(sk->sk_pacing_rate);
|
|
rate64 = rate != ~0U ? rate : ~0ULL;
|
|
nla_put_u64_64bit(stats, TCP_NLA_PACING_RATE, rate64, TCP_NLA_PAD);
|
|
|
|
rate64 = tcp_compute_delivery_rate(tp);
|
|
nla_put_u64_64bit(stats, TCP_NLA_DELIVERY_RATE, rate64, TCP_NLA_PAD);
|
|
|
|
nla_put_u32(stats, TCP_NLA_SND_CWND, tp->snd_cwnd);
|
|
nla_put_u32(stats, TCP_NLA_REORDERING, tp->reordering);
|
|
nla_put_u32(stats, TCP_NLA_MIN_RTT, tcp_min_rtt(tp));
|
|
|
|
nla_put_u8(stats, TCP_NLA_RECUR_RETRANS, inet_csk(sk)->icsk_retransmits);
|
|
nla_put_u8(stats, TCP_NLA_DELIVERY_RATE_APP_LMT, !!tp->rate_app_limited);
|
|
return stats;
|
|
}
|
|
|
|
static int do_tcp_getsockopt(struct sock *sk, int level,
|
|
int optname, char __user *optval, int __user *optlen)
|
|
{
|
|
struct inet_connection_sock *icsk = inet_csk(sk);
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct net *net = sock_net(sk);
|
|
int val, len;
|
|
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
|
|
len = min_t(unsigned int, len, sizeof(int));
|
|
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
|
|
switch (optname) {
|
|
case TCP_MAXSEG:
|
|
val = tp->mss_cache;
|
|
if (!val && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)))
|
|
val = tp->rx_opt.user_mss;
|
|
if (tp->repair)
|
|
val = tp->rx_opt.mss_clamp;
|
|
break;
|
|
case TCP_NODELAY:
|
|
val = !!(tp->nonagle&TCP_NAGLE_OFF);
|
|
break;
|
|
case TCP_CORK:
|
|
val = !!(tp->nonagle&TCP_NAGLE_CORK);
|
|
break;
|
|
case TCP_KEEPIDLE:
|
|
val = keepalive_time_when(tp) / HZ;
|
|
break;
|
|
case TCP_KEEPINTVL:
|
|
val = keepalive_intvl_when(tp) / HZ;
|
|
break;
|
|
case TCP_KEEPCNT:
|
|
val = keepalive_probes(tp);
|
|
break;
|
|
case TCP_SYNCNT:
|
|
val = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_syn_retries;
|
|
break;
|
|
case TCP_LINGER2:
|
|
val = tp->linger2;
|
|
if (val >= 0)
|
|
val = (val ? : net->ipv4.sysctl_tcp_fin_timeout) / HZ;
|
|
break;
|
|
case TCP_DEFER_ACCEPT:
|
|
val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept,
|
|
TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ);
|
|
break;
|
|
case TCP_WINDOW_CLAMP:
|
|
val = tp->window_clamp;
|
|
break;
|
|
case TCP_INFO: {
|
|
struct tcp_info info;
|
|
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
|
|
tcp_get_info(sk, &info);
|
|
|
|
len = min_t(unsigned int, len, sizeof(info));
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
if (copy_to_user(optval, &info, len))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case TCP_CC_INFO: {
|
|
const struct tcp_congestion_ops *ca_ops;
|
|
union tcp_cc_info info;
|
|
size_t sz = 0;
|
|
int attr;
|
|
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
|
|
ca_ops = icsk->icsk_ca_ops;
|
|
if (ca_ops && ca_ops->get_info)
|
|
sz = ca_ops->get_info(sk, ~0U, &attr, &info);
|
|
|
|
len = min_t(unsigned int, len, sz);
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
if (copy_to_user(optval, &info, len))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case TCP_QUICKACK:
|
|
val = !icsk->icsk_ack.pingpong;
|
|
break;
|
|
|
|
case TCP_CONGESTION:
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
len = min_t(unsigned int, len, TCP_CA_NAME_MAX);
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
if (copy_to_user(optval, icsk->icsk_ca_ops->name, len))
|
|
return -EFAULT;
|
|
return 0;
|
|
|
|
case TCP_ULP:
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
len = min_t(unsigned int, len, TCP_ULP_NAME_MAX);
|
|
if (!icsk->icsk_ulp_ops) {
|
|
if (put_user(0, optlen))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
if (copy_to_user(optval, icsk->icsk_ulp_ops->name, len))
|
|
return -EFAULT;
|
|
return 0;
|
|
|
|
case TCP_THIN_LINEAR_TIMEOUTS:
|
|
val = tp->thin_lto;
|
|
break;
|
|
|
|
case TCP_THIN_DUPACK:
|
|
val = 0;
|
|
break;
|
|
|
|
case TCP_REPAIR:
|
|
val = tp->repair;
|
|
break;
|
|
|
|
case TCP_REPAIR_QUEUE:
|
|
if (tp->repair)
|
|
val = tp->repair_queue;
|
|
else
|
|
return -EINVAL;
|
|
break;
|
|
|
|
case TCP_REPAIR_WINDOW: {
|
|
struct tcp_repair_window opt;
|
|
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
|
|
if (len != sizeof(opt))
|
|
return -EINVAL;
|
|
|
|
if (!tp->repair)
|
|
return -EPERM;
|
|
|
|
opt.snd_wl1 = tp->snd_wl1;
|
|
opt.snd_wnd = tp->snd_wnd;
|
|
opt.max_window = tp->max_window;
|
|
opt.rcv_wnd = tp->rcv_wnd;
|
|
opt.rcv_wup = tp->rcv_wup;
|
|
|
|
if (copy_to_user(optval, &opt, len))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
case TCP_QUEUE_SEQ:
|
|
if (tp->repair_queue == TCP_SEND_QUEUE)
|
|
val = tp->write_seq;
|
|
else if (tp->repair_queue == TCP_RECV_QUEUE)
|
|
val = tp->rcv_nxt;
|
|
else
|
|
return -EINVAL;
|
|
break;
|
|
|
|
case TCP_USER_TIMEOUT:
|
|
val = jiffies_to_msecs(icsk->icsk_user_timeout);
|
|
break;
|
|
|
|
case TCP_FASTOPEN:
|
|
val = icsk->icsk_accept_queue.fastopenq.max_qlen;
|
|
break;
|
|
|
|
case TCP_FASTOPEN_CONNECT:
|
|
val = tp->fastopen_connect;
|
|
break;
|
|
|
|
case TCP_TIMESTAMP:
|
|
val = tcp_time_stamp_raw() + tp->tsoffset;
|
|
break;
|
|
case TCP_NOTSENT_LOWAT:
|
|
val = tp->notsent_lowat;
|
|
break;
|
|
case TCP_SAVE_SYN:
|
|
val = tp->save_syn;
|
|
break;
|
|
case TCP_SAVED_SYN: {
|
|
if (get_user(len, optlen))
|
|
return -EFAULT;
|
|
|
|
lock_sock(sk);
|
|
if (tp->saved_syn) {
|
|
if (len < tp->saved_syn[0]) {
|
|
if (put_user(tp->saved_syn[0], optlen)) {
|
|
release_sock(sk);
|
|
return -EFAULT;
|
|
}
|
|
release_sock(sk);
|
|
return -EINVAL;
|
|
}
|
|
len = tp->saved_syn[0];
|
|
if (put_user(len, optlen)) {
|
|
release_sock(sk);
|
|
return -EFAULT;
|
|
}
|
|
if (copy_to_user(optval, tp->saved_syn + 1, len)) {
|
|
release_sock(sk);
|
|
return -EFAULT;
|
|
}
|
|
tcp_saved_syn_free(tp);
|
|
release_sock(sk);
|
|
} else {
|
|
release_sock(sk);
|
|
len = 0;
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
}
|
|
return 0;
|
|
}
|
|
default:
|
|
return -ENOPROTOOPT;
|
|
}
|
|
|
|
if (put_user(len, optlen))
|
|
return -EFAULT;
|
|
if (copy_to_user(optval, &val, len))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
|
|
int __user *optlen)
|
|
{
|
|
struct inet_connection_sock *icsk = inet_csk(sk);
|
|
|
|
if (level != SOL_TCP)
|
|
return icsk->icsk_af_ops->getsockopt(sk, level, optname,
|
|
optval, optlen);
|
|
return do_tcp_getsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
EXPORT_SYMBOL(tcp_getsockopt);
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
int compat_tcp_getsockopt(struct sock *sk, int level, int optname,
|
|
char __user *optval, int __user *optlen)
|
|
{
|
|
if (level != SOL_TCP)
|
|
return inet_csk_compat_getsockopt(sk, level, optname,
|
|
optval, optlen);
|
|
return do_tcp_getsockopt(sk, level, optname, optval, optlen);
|
|
}
|
|
EXPORT_SYMBOL(compat_tcp_getsockopt);
|
|
#endif
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
static DEFINE_PER_CPU(struct tcp_md5sig_pool, tcp_md5sig_pool);
|
|
static DEFINE_MUTEX(tcp_md5sig_mutex);
|
|
static bool tcp_md5sig_pool_populated = false;
|
|
|
|
static void __tcp_alloc_md5sig_pool(void)
|
|
{
|
|
struct crypto_ahash *hash;
|
|
int cpu;
|
|
|
|
hash = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC);
|
|
if (IS_ERR(hash))
|
|
return;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
void *scratch = per_cpu(tcp_md5sig_pool, cpu).scratch;
|
|
struct ahash_request *req;
|
|
|
|
if (!scratch) {
|
|
scratch = kmalloc_node(sizeof(union tcp_md5sum_block) +
|
|
sizeof(struct tcphdr),
|
|
GFP_KERNEL,
|
|
cpu_to_node(cpu));
|
|
if (!scratch)
|
|
return;
|
|
per_cpu(tcp_md5sig_pool, cpu).scratch = scratch;
|
|
}
|
|
if (per_cpu(tcp_md5sig_pool, cpu).md5_req)
|
|
continue;
|
|
|
|
req = ahash_request_alloc(hash, GFP_KERNEL);
|
|
if (!req)
|
|
return;
|
|
|
|
ahash_request_set_callback(req, 0, NULL, NULL);
|
|
|
|
per_cpu(tcp_md5sig_pool, cpu).md5_req = req;
|
|
}
|
|
/* before setting tcp_md5sig_pool_populated, we must commit all writes
|
|
* to memory. See smp_rmb() in tcp_get_md5sig_pool()
|
|
*/
|
|
smp_wmb();
|
|
tcp_md5sig_pool_populated = true;
|
|
}
|
|
|
|
bool tcp_alloc_md5sig_pool(void)
|
|
{
|
|
if (unlikely(!tcp_md5sig_pool_populated)) {
|
|
mutex_lock(&tcp_md5sig_mutex);
|
|
|
|
if (!tcp_md5sig_pool_populated)
|
|
__tcp_alloc_md5sig_pool();
|
|
|
|
mutex_unlock(&tcp_md5sig_mutex);
|
|
}
|
|
return tcp_md5sig_pool_populated;
|
|
}
|
|
EXPORT_SYMBOL(tcp_alloc_md5sig_pool);
|
|
|
|
|
|
/**
|
|
* tcp_get_md5sig_pool - get md5sig_pool for this user
|
|
*
|
|
* We use percpu structure, so if we succeed, we exit with preemption
|
|
* and BH disabled, to make sure another thread or softirq handling
|
|
* wont try to get same context.
|
|
*/
|
|
struct tcp_md5sig_pool *tcp_get_md5sig_pool(void)
|
|
{
|
|
local_bh_disable();
|
|
|
|
if (tcp_md5sig_pool_populated) {
|
|
/* coupled with smp_wmb() in __tcp_alloc_md5sig_pool() */
|
|
smp_rmb();
|
|
return this_cpu_ptr(&tcp_md5sig_pool);
|
|
}
|
|
local_bh_enable();
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(tcp_get_md5sig_pool);
|
|
|
|
int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp,
|
|
const struct sk_buff *skb, unsigned int header_len)
|
|
{
|
|
struct scatterlist sg;
|
|
const struct tcphdr *tp = tcp_hdr(skb);
|
|
struct ahash_request *req = hp->md5_req;
|
|
unsigned int i;
|
|
const unsigned int head_data_len = skb_headlen(skb) > header_len ?
|
|
skb_headlen(skb) - header_len : 0;
|
|
const struct skb_shared_info *shi = skb_shinfo(skb);
|
|
struct sk_buff *frag_iter;
|
|
|
|
sg_init_table(&sg, 1);
|
|
|
|
sg_set_buf(&sg, ((u8 *) tp) + header_len, head_data_len);
|
|
ahash_request_set_crypt(req, &sg, NULL, head_data_len);
|
|
if (crypto_ahash_update(req))
|
|
return 1;
|
|
|
|
for (i = 0; i < shi->nr_frags; ++i) {
|
|
const struct skb_frag_struct *f = &shi->frags[i];
|
|
unsigned int offset = f->page_offset;
|
|
struct page *page = skb_frag_page(f) + (offset >> PAGE_SHIFT);
|
|
|
|
sg_set_page(&sg, page, skb_frag_size(f),
|
|
offset_in_page(offset));
|
|
ahash_request_set_crypt(req, &sg, NULL, skb_frag_size(f));
|
|
if (crypto_ahash_update(req))
|
|
return 1;
|
|
}
|
|
|
|
skb_walk_frags(skb, frag_iter)
|
|
if (tcp_md5_hash_skb_data(hp, frag_iter, 0))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(tcp_md5_hash_skb_data);
|
|
|
|
int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *key)
|
|
{
|
|
struct scatterlist sg;
|
|
|
|
sg_init_one(&sg, key->key, key->keylen);
|
|
ahash_request_set_crypt(hp->md5_req, &sg, NULL, key->keylen);
|
|
return crypto_ahash_update(hp->md5_req);
|
|
}
|
|
EXPORT_SYMBOL(tcp_md5_hash_key);
|
|
|
|
#endif
|
|
|
|
void tcp_done(struct sock *sk)
|
|
{
|
|
struct request_sock *req = tcp_sk(sk)->fastopen_rsk;
|
|
|
|
if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV)
|
|
TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS);
|
|
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
tcp_clear_xmit_timers(sk);
|
|
if (req)
|
|
reqsk_fastopen_remove(sk, req, false);
|
|
|
|
sk->sk_shutdown = SHUTDOWN_MASK;
|
|
|
|
if (!sock_flag(sk, SOCK_DEAD))
|
|
sk->sk_state_change(sk);
|
|
else
|
|
inet_csk_destroy_sock(sk);
|
|
}
|
|
EXPORT_SYMBOL_GPL(tcp_done);
|
|
|
|
int tcp_abort(struct sock *sk, int err)
|
|
{
|
|
if (!sk_fullsock(sk)) {
|
|
if (sk->sk_state == TCP_NEW_SYN_RECV) {
|
|
struct request_sock *req = inet_reqsk(sk);
|
|
|
|
local_bh_disable();
|
|
inet_csk_reqsk_queue_drop_and_put(req->rsk_listener,
|
|
req);
|
|
local_bh_enable();
|
|
return 0;
|
|
}
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
/* Don't race with userspace socket closes such as tcp_close. */
|
|
lock_sock(sk);
|
|
|
|
if (sk->sk_state == TCP_LISTEN) {
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
inet_csk_listen_stop(sk);
|
|
}
|
|
|
|
/* Don't race with BH socket closes such as inet_csk_listen_stop. */
|
|
local_bh_disable();
|
|
bh_lock_sock(sk);
|
|
|
|
if (!sock_flag(sk, SOCK_DEAD)) {
|
|
sk->sk_err = err;
|
|
/* This barrier is coupled with smp_rmb() in tcp_poll() */
|
|
smp_wmb();
|
|
sk->sk_error_report(sk);
|
|
if (tcp_need_reset(sk->sk_state))
|
|
tcp_send_active_reset(sk, GFP_ATOMIC);
|
|
tcp_done(sk);
|
|
}
|
|
|
|
bh_unlock_sock(sk);
|
|
local_bh_enable();
|
|
release_sock(sk);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(tcp_abort);
|
|
|
|
extern struct tcp_congestion_ops tcp_reno;
|
|
|
|
static __initdata unsigned long thash_entries;
|
|
static int __init set_thash_entries(char *str)
|
|
{
|
|
ssize_t ret;
|
|
|
|
if (!str)
|
|
return 0;
|
|
|
|
ret = kstrtoul(str, 0, &thash_entries);
|
|
if (ret)
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
__setup("thash_entries=", set_thash_entries);
|
|
|
|
static void __init tcp_init_mem(void)
|
|
{
|
|
unsigned long limit = nr_free_buffer_pages() / 16;
|
|
|
|
limit = max(limit, 128UL);
|
|
sysctl_tcp_mem[0] = limit / 4 * 3; /* 4.68 % */
|
|
sysctl_tcp_mem[1] = limit; /* 6.25 % */
|
|
sysctl_tcp_mem[2] = sysctl_tcp_mem[0] * 2; /* 9.37 % */
|
|
}
|
|
|
|
void __init tcp_init(void)
|
|
{
|
|
int max_rshare, max_wshare, cnt;
|
|
unsigned long limit;
|
|
unsigned int i;
|
|
|
|
BUILD_BUG_ON(sizeof(struct tcp_skb_cb) >
|
|
FIELD_SIZEOF(struct sk_buff, cb));
|
|
|
|
percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL);
|
|
percpu_counter_init(&tcp_orphan_count, 0, GFP_KERNEL);
|
|
inet_hashinfo_init(&tcp_hashinfo);
|
|
tcp_hashinfo.bind_bucket_cachep =
|
|
kmem_cache_create("tcp_bind_bucket",
|
|
sizeof(struct inet_bind_bucket), 0,
|
|
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
|
|
|
|
/* Size and allocate the main established and bind bucket
|
|
* hash tables.
|
|
*
|
|
* The methodology is similar to that of the buffer cache.
|
|
*/
|
|
tcp_hashinfo.ehash =
|
|
alloc_large_system_hash("TCP established",
|
|
sizeof(struct inet_ehash_bucket),
|
|
thash_entries,
|
|
17, /* one slot per 128 KB of memory */
|
|
0,
|
|
NULL,
|
|
&tcp_hashinfo.ehash_mask,
|
|
0,
|
|
thash_entries ? 0 : 512 * 1024);
|
|
for (i = 0; i <= tcp_hashinfo.ehash_mask; i++)
|
|
INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].chain, i);
|
|
|
|
if (inet_ehash_locks_alloc(&tcp_hashinfo))
|
|
panic("TCP: failed to alloc ehash_locks");
|
|
tcp_hashinfo.bhash =
|
|
alloc_large_system_hash("TCP bind",
|
|
sizeof(struct inet_bind_hashbucket),
|
|
tcp_hashinfo.ehash_mask + 1,
|
|
17, /* one slot per 128 KB of memory */
|
|
0,
|
|
&tcp_hashinfo.bhash_size,
|
|
NULL,
|
|
0,
|
|
64 * 1024);
|
|
tcp_hashinfo.bhash_size = 1U << tcp_hashinfo.bhash_size;
|
|
for (i = 0; i < tcp_hashinfo.bhash_size; i++) {
|
|
spin_lock_init(&tcp_hashinfo.bhash[i].lock);
|
|
INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain);
|
|
}
|
|
|
|
|
|
cnt = tcp_hashinfo.ehash_mask + 1;
|
|
sysctl_tcp_max_orphans = cnt / 2;
|
|
|
|
tcp_init_mem();
|
|
/* Set per-socket limits to no more than 1/128 the pressure threshold */
|
|
limit = nr_free_buffer_pages() << (PAGE_SHIFT - 7);
|
|
max_wshare = min(4UL*1024*1024, limit);
|
|
max_rshare = min(6UL*1024*1024, limit);
|
|
|
|
sysctl_tcp_wmem[0] = SK_MEM_QUANTUM;
|
|
sysctl_tcp_wmem[1] = 16*1024;
|
|
sysctl_tcp_wmem[2] = max(64*1024, max_wshare);
|
|
|
|
sysctl_tcp_rmem[0] = SK_MEM_QUANTUM;
|
|
sysctl_tcp_rmem[1] = 87380;
|
|
sysctl_tcp_rmem[2] = max(87380, max_rshare);
|
|
|
|
pr_info("Hash tables configured (established %u bind %u)\n",
|
|
tcp_hashinfo.ehash_mask + 1, tcp_hashinfo.bhash_size);
|
|
|
|
tcp_v4_init();
|
|
tcp_metrics_init();
|
|
BUG_ON(tcp_register_congestion_control(&tcp_reno) != 0);
|
|
tcp_tasklet_init();
|
|
}
|