Commit Graph

136 Commits

Author SHA1 Message Date
djm@openbsd.org d6556de1db upstream: fix poll() spin when a channel's output fd closes without
data in the channel buffer. Introduce more exact packing of channel fds into
the pollfd array. fixes bz3405 and bz3411; ok deraadt@ markus@

OpenBSD-Commit-ID: 06740737849c9047785622ad5d472cb6a3907d10
2022-03-31 08:16:38 +11:00
djm@openbsd.org b30d32159d upstream: add a ssh_packet_process_read() function that reads from
a fd directly into the transport input buffer.

Use this in the client and server mainloops to avoid unnecessary
copying. It also lets us use a more greedy read size without penalty.

Yields a 2-3% performance gain on cipher-speed.sh (in a fairly
unscientific test tbf)

feedback dtucker@ ok markus@

OpenBSD-Commit-ID: df4112125bf79d8e38e79a77113e1b373078e632
2022-01-25 12:18:35 +11:00
djm@openbsd.org 17877bc81d upstream: convert ssh, sshd mainloops from select() to poll();
feedback & ok deraadt@ and markus@ has been in snaps for a few months

OpenBSD-Commit-ID: a77e16a667d5b194dcdb3b76308b8bba7fa7239c
2022-01-07 09:21:38 +11:00
djm@openbsd.org 5c79952dfe upstream: prepare for conversion of ssh, sshd mainloop from
select() to poll() by moving FD_SET construction out of channel handlers into
separate functions. ok markus

OpenBSD-Commit-ID: 937fbf2a4de12b19fb9d5168424e206124807027
2022-01-07 09:11:58 +11:00
djm@openbsd.org 7be4ac8136 upstream: restore blocking status on stdio fds before close
ssh(1) needs to set file descriptors to non-blocking mode to operate
but it was not restoring the original state on exit. This could cause
problems with fds shared with other programs via the shell, e.g.

> $ cat > test.sh << _EOF
> #!/bin/sh
> {
>         ssh -Fnone -oLogLevel=verbose ::1 hostname
>         cat /usr/share/dict/words
> } | sleep 10
> _EOF
> $ ./test.sh
> Authenticated to ::1 ([::1]:22).
> Transferred: sent 2352, received 2928 bytes, in 0.1 seconds
> Bytes per second: sent 44338.9, received 55197.4
> cat: stdout: Resource temporarily unavailable

This restores the blocking status for fds 0,1,2 (stdio) before ssh(1)
abandons/closes them.

This was reported as bz3280 and GHPR246; ok dtucker@

OpenBSD-Commit-ID: 8cc67346f05aa85a598bddf2383fcfcc3aae61ce
2021-05-19 11:52:14 +10:00
djm@openbsd.org 31d8d231eb upstream: highly polished whitespace, mostly fixing spaces-for-tab
and bad indentation on continuation lines. Prompted by GHPR#185

OpenBSD-Commit-ID: e5c81f0cbdcc6144df1ce468ec1bac366d8ad6e9
2021-04-03 17:23:02 +11:00
djm@openbsd.org 34afde5c73 upstream: whitespace (tab after space)
OpenBSD-Commit-ID: 0e2b3f7674e985d3f7c27ff5028e690ba1c2efd4
2021-04-03 17:20:00 +11:00
djm@openbsd.org 107eb3eeaf upstream: cap channel input buffer size at 16MB; avoids high memory use
when peer advertises a large window but is slow to consume the data we send
(e.g. because of a slow network)

reported by Pierre-Yves David

fix with & ok markus@

OpenBSD-Commit-ID: 1452771f5e5e768876d3bfe2544e3866d6ade216
2020-09-20 16:16:46 +10:00
djm@openbsd.org 6d755706a0 upstream: some language improvements; ok markus
OpenBSD-Commit-ID: 939d787d571b4d5da50b3b721fd0b2ac236acaa8
2020-07-15 15:07:42 +10:00
djm@openbsd.org 065064fcf4 upstream: add a comment describing the ranges of channel IDs that
we use; requested by markus@

OpenBSD-Commit-ID: 83a1f09810ffa3a96a55fbe32675b34ba739e56b
2020-01-26 10:15:13 +11:00
djm@openbsd.org f1dd179e12 upstream: include a little more information about the status and
disposition of channel's extended (stderr) fd; makes debugging some things a
bit easier. No behaviour change.

OpenBSD-Commit-ID: 483eb6467dc7d5dbca8eb109c453e7a43075f7ce
2018-10-04 10:44:49 +10:00
djm@openbsd.org 115063a664 upstream: Add a PermitListen directive to control which server-side
addresses may be listened on when the client requests remote forwarding (ssh
-R).

This is the converse of the existing PermitOpen directive and this
includes some refactoring to share much of its implementation.

feedback and ok markus@

OpenBSD-Commit-ID: 15a931238c61a3f2ac74ea18a98c933e358e277f
2018-06-07 04:27:20 +10:00
markus@openbsd.org 609d7a66ce upstream commit
Add 'reverse' dynamic forwarding which combines dynamic
forwarding (-D) with remote forwarding (-R) where the remote-forwarded port
expects SOCKS-requests.

The SSH server code is unchanged and the parsing happens at the SSH
clients side. Thus the full SOCKS-request is sent over the forwarded
channel and the client parses c->output. Parsing happens in
channel_before_prepare_select(), _before_ the select bitmask is
computed in the pre[] handlers, but after network input processing
in the post[] handlers.

help and ok djm@

Upstream-ID: aa25a6a3851064f34fe719e0bf15656ad5a64b89
2017-09-22 09:14:53 +10:00
djm@openbsd.org 9f53229c2a upstream commit
Make remote channel ID a u_int

Previously we tracked the remote channel IDs in an int, but this is
strictly incorrect: the wire protocol uses uint32 and there is nothing
in-principle stopping a SSH implementation from sending, say, 0xffff0000.

In practice everyone numbers their channels sequentially, so this has
never been a problem.

ok markus@

Upstream-ID: b9f4cd3dc53155b4a5c995c0adba7da760d03e73
2017-09-12 17:37:03 +10:00
djm@openbsd.org dbee4119b5 upstream commit
refactor channels.c

Move static state to a "struct ssh_channels" that is allocated at
runtime and tracked as a member of struct ssh.

Explicitly pass "struct ssh" to all channels functions.

Replace use of the legacy packet APIs in channels.c.

Rework sshd_config PermitOpen handling: previously the configuration
parser would call directly into the channels layer. After the refactor
this is not possible, as the channels structures are allocated at
connection time and aren't available when the configuration is parsed.
The server config parser now tracks PermitOpen itself and explicitly
configures the channels code later.

ok markus@

Upstream-ID: 11828f161656b965cc306576422613614bea2d8f
2017-09-12 17:37:02 +10:00
djm@openbsd.org 71e5a536ec upstream commit
pass packet state down to some of the channels function
(more to come...); ok markus@

Upstream-ID: d8ce7a94f4059d7ac1e01fb0eb01de0c4b36c81b
2017-09-04 09:38:57 +10:00
markus@openbsd.org 2ae666a8fc upstream commit
protocol handlers all get struct ssh passed; ok djm@

Upstream-ID: 0ca9ea2a5d01a6d2ded94c5024456a930c5bfb5d
2017-05-31 10:50:05 +10:00
markus@openbsd.org 6cf711752c upstream commit
remove SSH_CHANNEL_XXX_DRAINING (ssh1 only); ok djm@

Upstream-ID: e2e225b6ac67b84dd024f38819afff2554fafe42
2017-05-27 15:35:52 +10:00
markus@openbsd.org 364f0d5ede upstream commit
remove channel_input_close_confirmation (ssh1 only); ok
djm@

Upstream-ID: 8e7c8c38f322d255bb0294a5c0ebef53fdf576f1
2017-05-27 15:35:52 +10:00
djm@openbsd.org 930e8d2827 upstream commit
obliterate ssh1.h and some dead code that used it

ok markus@

Upstream-ID: 1ca9159a9fb95618f9d51e069ac8e1131a087343
2017-05-01 10:05:06 +10:00
djm@openbsd.org 97f4d3083b upstream commit
remove compat20/compat13/compat15 variables

ok markus@

Upstream-ID: 43802c035ceb3fef6c50c400e4ecabf12354691c
2017-05-01 09:42:37 +10:00
dtucker@openbsd.org 858252fb1d upstream commit
Return true reason for port forwarding failures where
feasible rather than always "administratively prohibited".  bz#2674, ok djm@

Upstream-ID: d901d9887951774e604ca970e1827afaaef9e419
2017-02-03 14:23:24 +11:00
dtucker@openbsd.org 246aa842a4 upstream commit
Remove channel_input_port_forward_request(); the only caller
was the recently-removed SSH1 server code so it's now dead code.  ok markus@

Upstream-ID: 05453983230a1f439562535fec2818f63f297af9
2016-10-19 07:16:01 +11:00
markus@openbsd.org 8d05784785 upstream commit
ssh proxy mux mode (-O proxy; idea from Simon Tatham): - mux
client speaks the ssh-packet protocol directly over unix-domain socket. - mux
server acts as a proxy, translates channel IDs and relays to the server. - no
filedescriptor passing necessary. - combined with unix-domain forwarding it's
even possible to run mux client   and server on different machines. feedback
& ok djm@

Upstream-ID: 666a2fb79f58e5c50e246265fb2b9251e505c25b
2016-10-01 02:45:10 +10:00
djm@openbsd.org 1bf477d3cd upstream commit
better refuse ForwardX11Trusted=no connections attempted
 after ForwardX11Timeout expires; reported by Jann Horn

Upstream-ID: bf0fddadc1b46a0334e26c080038313b4b6dea21
2015-07-01 12:29:43 +10:00
djm@openbsd.org c28a3436fa upstream commit
moar whitespace at eol

Upstream-ID: 64eaf872a3ba52ed41e494287e80d40aaba4b515
2015-05-08 16:46:01 +10:00
markus@openbsd.org 3fdc88a0de upstream commit
move dispatch to struct ssh; ok djm@
2015-01-20 09:14:16 +11:00
Damien Miller 7acefbbcbe - millert@cvs.openbsd.org 2014/07/15 15:54:14
[PROTOCOL auth-options.c auth-passwd.c auth-rh-rsa.c auth-rhosts.c]
     [auth-rsa.c auth.c auth1.c auth2-hostbased.c auth2-kbdint.c auth2-none.c]
     [auth2-passwd.c auth2-pubkey.c auth2.c canohost.c channels.c channels.h]
     [clientloop.c misc.c misc.h monitor.c mux.c packet.c readconf.c]
     [readconf.h servconf.c servconf.h serverloop.c session.c ssh-agent.c]
     [ssh.c ssh_config.5 sshconnect.c sshconnect1.c sshconnect2.c sshd.c]
     [sshd_config.5 sshlogin.c]
     Add support for Unix domain socket forwarding.  A remote TCP port
     may be forwarded to a local Unix domain socket and vice versa or
     both ends may be a Unix domain socket.  This is a reimplementation
     of the streamlocal patches by William Ahern from:
         http://www.25thandclement.com/~william/projects/streamlocal.html
     OK djm@ markus@
2014-07-18 14:11:24 +10:00
Damien Miller 4b3ed647d5 - markus@cvs.openbsd.org 2014/06/27 16:41:56
[channels.c channels.h clientloop.c ssh.c]
     fix remote fwding with same listen port but different listen address
     with gerhard@, ok djm@
2014-07-02 15:29:40 +10:00
Damien Miller c192a4c4f6 - (djm) [channels.c channels.h] bz#2135: On Solaris, isatty() on a non-
blocking connecting socket will clear any stored errno that might
   otherwise have been retrievable via getsockopt(). A hack to limit writes
   to TTYs on AIX was triggering this. Since only AIX needs the hack, wrap
   it in an #ifdef. Diagnosis and patch from Ivo Raisr.
2013-08-01 14:29:20 +10:00
Damien Miller 36187093ea - dtucker@cvs.openbsd.org 2013/06/07 15:37:52
[channels.c channels.h clientloop.c]
     Add an "ABANDONED" channel state and use for mux sessions that are
     disconnected via the ~. escape sequence.  Channels in this state will
     be able to close if the server responds, but do not count as active channels.
     This means that if you ~. all of the mux clients when using ControlPersist
     on a broken network, the backgrounded mux master will exit when the
     Control Persist time expires rather than hanging around indefinitely.
     bz#1917, also reported and tested by tedu@.  ok djm@ markus@.
2013-06-10 13:07:11 +10:00
Darren Tucker 5d12b8f05d - dtucker@cvs.openbsd.org 2013/06/02 21:01:51
[channels.h]
     typo in comment
2013-06-06 08:09:10 +10:00
Damien Miller a6508753db - djm@cvs.openbsd.org 2012/04/11 13:16:19
[channels.c channels.h clientloop.c serverloop.c]
     don't spin in accept() when out of fds (ENFILE/ENFILE) - back off for a
     while; ok deraadt@ markus@
2012-04-22 11:21:10 +10:00
Damien Miller c6081482b2 - dtucker@cvs.openbsd.org 2012/03/29 23:54:36
[channels.c channels.h servconf.c]
     Add PermitOpen none option based on patch from Loganaden Velvindron
     (bz #1949).  ok djm@
2012-04-22 11:18:53 +10:00
Darren Tucker 68afb8c5f2 - markus@cvs.openbsd.org 2011/09/23 07:45:05
[mux.c readconf.h channels.h compat.h compat.c ssh.c readconf.c channels.c     version.h]
     unbreak remote portforwarding with dynamic allocated listen ports:
     1) send the actual listen port in the open message (instead of 0).
        this allows multiple forwardings with a dynamic listen port
     2) update the matching permit-open entry, so we can identify where
        to connect to
     report: den at skbkontur.ru and P. Szczygielski
     feedback and ok djm@
2011-10-02 18:59:03 +11:00
Darren Tucker 1338b9e067 - dtucker@cvs.openbsd.org 2011/09/23 00:22:04
[channels.c auth-options.c servconf.c channels.h sshd.8]
     Add wildcard support to PermitOpen, allowing things like "PermitOpen
     localhost:*".  bz #1857, ok djm markus.
2011-10-02 18:57:35 +11:00
Damien Miller ff773644e6 - markus@cvs.openbsd.org 2011/09/10 22:26:34
[channels.c channels.h clientloop.c ssh.1]
     support cancellation of local/dynamic forwardings from ~C commandline;
     ok & feedback djm@
2011-09-22 21:39:48 +10:00
Damien Miller f6dff7cd2f - djm@cvs.openbsd.org 2011/09/09 22:46:44
[channels.c channels.h clientloop.h mux.c ssh.c]
     support for cancelling local and remote port forwards via the multiplex
     socket. Use ssh -O cancel -L xx:xx:xx -R yy:yy:yy user@host" to request
     the cancellation of the specified forwardings; ok markus@
2011-09-22 21:38:52 +10:00
Damien Miller 6d7b4377dd - djm@cvs.openbsd.org 2011/06/22 22:08:42
[channels.c channels.h clientloop.c clientloop.h mux.c ssh.c]
     hook up a channel confirm callback to warn the user then requested X11
     forwarding was refused by the server; ok markus@
2011-06-23 08:31:57 +10:00
Damien Miller d530f5f471 - djm@cvs.openbsd.org 2010/05/14 23:29:23
[channels.c channels.h mux.c ssh.c]
     Pause the mux channel while waiting for reply from aynch callbacks.
     Prevents misordering of replies if new requests arrive while waiting.

     Extend channel open confirm callback to allow signalling failure
     conditions as well as success. Use this to 1) fix a memory leak, 2)
     start using the above pause mechanism and 3) delay sending a success/
     failure message on mux slave session open until we receive a reply from
     the server.

     motivated by and with feedback from markus@
2010-05-21 14:57:10 +10:00
Damien Miller e1537f951f - djm@cvs.openbsd.org 2010/01/26 01:28:35
[channels.c channels.h clientloop.c clientloop.h mux.c nchan.c ssh.c]
     rewrite ssh(1) multiplexing code to a more sensible protocol.

     The new multiplexing code uses channels for the listener and
     accepted control sockets to make the mux master non-blocking, so
     no stalls when processing messages from a slave.

     avoid use of fatal() in mux master protocol parsing so an errant slave
     process cannot take down a running master.

     implement requesting of port-forwards over multiplexed sessions. Any
     port forwards requested by the slave are added to those the master has
     established.

     add support for stdio forwarding ("ssh -W host:port ...") in mux slaves.

     document master/slave mux protocol so that other tools can use it to
     control a running ssh(1). Note: there are no guarantees that this
     protocol won't be incompatibly changed (though it is versioned).

     feedback Salvador Fandino, dtucker@
     channel changes ok markus@
2010-01-26 13:26:22 +11:00
Darren Tucker 7ad8dd21da - dtucker@cvs.openbsd.org 2010/01/11 01:39:46
[ssh_config channels.c ssh.1 channels.h ssh.c]
     Add a 'netcat mode' (ssh -W).  This connects stdio on the client to a
     single port forward on the server.  This allows, for example, using ssh as
     a ProxyCommand to route connections via intermediate servers.
     bz #1618, man page help from jmc@, ok markus@
2010-01-12 19:40:27 +11:00
Darren Tucker 7bd98e7f74 - dtucker@cvs.openbsd.org 2010/01/09 23:04:13
[channels.c ssh.1 servconf.c sshd_config.5 sshd.c channels.h servconf.h
     ssh-keyscan.1 ssh-keyscan.c readconf.c sshconnect.c misc.c ssh.c
     readconf.h scp.1 sftp.1 ssh_config.5 misc.h]
     Remove RoutingDomain from ssh since it's now not needed.  It can be
     replaced with "route exec" or "nc -V" as a proxycommand.  "route exec"
     also ensures that trafic such as DNS lookups stays withing the specified
     routingdomain.  For example (from reyk):
     # route -T 2 exec /usr/sbin/sshd
     or inherited from the parent process
     $ route -T 2 exec sh
     $ ssh 10.1.2.3
     ok deraadt@ markus@ stevesk@ reyk@
2010-01-10 10:31:12 +11:00
Darren Tucker 876045b0fb - markus@cvs.openbsd.org 2009/11/11 21:37:03
[channels.c channels.h]
     fix race condition in x11/agent channel allocation: don't read after
     the end of the select read/write fdset and make sure a reused FD
     is not touched before the pre-handlers are called.
     with and ok djm@
2010-01-08 17:08:00 +11:00
Darren Tucker 34e314da1b - reyk@cvs.openbsd.org 2009/10/28 16:38:18
[ssh_config.5 sshd.c misc.h ssh-keyscan.1 readconf.h sshconnect.c
     channels.c channels.h servconf.h servconf.c ssh.1 ssh-keyscan.c scp.1
     sftp.1 sshd_config.5 readconf.c ssh.c misc.c]
     Allow to set the rdomain in ssh/sftp/scp/sshd and ssh-keyscan.
     ok markus@
2010-01-08 17:03:46 +11:00
Damien Miller 4bf648f776 - djm@cvs.openbsd.org 2009/02/12 03:00:56
[canohost.c canohost.h channels.c channels.h clientloop.c readconf.c]
     [readconf.h serverloop.c ssh.c]
     support remote port forwarding with a zero listen port (-R0:...) to
     dyamically allocate a listen port at runtime (this is actually
     specified in rfc4254); bz#1003 ok markus@
2009-02-14 16:28:21 +11:00
Damien Miller a1c1b6c86d - djm@cvs.openbsd.org 2009/01/22 09:46:01
[channels.c channels.h session.c]
     make Channel->path an allocated string, saving a few bytes here and
     there and fixing bz#1380 in the process; ok markus@
2009-01-28 16:29:49 +11:00
Damien Miller d310d51bad - djm@cvs.openbsd.org 2008/06/15 20:06:26
[channels.c channels.h session.c]
     don't call isatty() on a pty master, instead pass a flag down to
     channel_set_fds() indicating that te fds refer to a tty. Fixes a
     hang on exit on Solaris (bz#1463) in portable but is actually
     a generic bug; ok dtucker deraadt markus
2008-06-16 07:59:23 +10:00
Darren Tucker 84c56f536c - djm@cvs.openbsd.org 2008/06/12 15:19:17
[clientloop.h channels.h clientloop.c channels.c mux.c]
     The multiplexing escape char handler commit last night introduced a
     small memory leak per session; plug it.
2008-06-13 04:55:46 +10:00
Darren Tucker 2fb66caca2 - djm@cvs.openbsd.org 2008/06/12 03:40:52
[clientloop.h mux.c channels.c clientloop.c channels.h]
     Enable ~ escapes for multiplex slave sessions; give each channel
     its own escape state and hook the escape filters up to muxed
     channels. bz #1331
     Mux slaves do not currently support the ~^Z and ~& escapes.
     NB. this change cranks the mux protocol version, so a new ssh
     mux client will not be able to connect to a running old ssh
     mux master.
     ok dtucker@
2008-06-13 04:49:33 +10:00