exactly the flags that ssh started with and don't just clobber them with
zero, as this could also remove the append flag from the set;
bz3523; ok dtucker@
OpenBSD-Commit-ID: 1336b03e881db7564a4b66014eb24c5230e9a0c0
This adds a sshd_config ChannelTimeouts directive that allows channels that
have not seen traffic in a configurable interval to be automatically closed.
Different timeouts may be applied to session, X11, agent and TCP forwarding
channels.
Note: this only affects channels over an opened SSH connection and not
the connection itself. Most clients close the connection when their channels
go away, with a notable exception being ssh(1) in multiplexing mode.
ok markus dtucker
OpenBSD-Commit-ID: ae8bba3ed9d9f95ff2e2dc8dcadfa36b48e6c0b8
This sets an "extended" channel type after channel creation (e.g.
"session:subsystem:sftp") that will be used for setting channel inactivity
timeouts.
ok markus dtucker
OpenBSD-Commit-ID: 42564aa92345045b4a74300528f960416a15d4ca
This will forcibly close an open channel by simulating read/write errors,
draining the IO buffers and calling the detach function.
Previously the detach function was only ever called during channel garbage
collection, but there was no way to signal the user of a channel (e.g.
session.c) that its channel was being closed deliberately (vs. by the
usual state-machine logic). So this adds an extra "force" argument to the
channel cleanup callback to indicate this condition.
ok markus dtucker
OpenBSD-Commit-ID: 23052707a42bdc62fda2508636e624afd466324b
comment accordingly. As remote_name is not modified, it can be const as
well. From Martin Vahlensieck
OpenBSD-Commit-ID: e4e10dc8dc9f40c166ea5a8e991942bedc75a76a
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
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
select() to poll() by moving FD_SET construction out of channel handlers into
separate functions. ok markus
OpenBSD-Commit-ID: 937fbf2a4de12b19fb9d5168424e206124807027
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
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
disposition of channel's extended (stderr) fd; makes debugging some things a
bit easier. No behaviour change.
OpenBSD-Commit-ID: 483eb6467dc7d5dbca8eb109c453e7a43075f7ce
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
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
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
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
Return true reason for port forwarding failures where
feasible rather than always "administratively prohibited". bz#2674, ok djm@
Upstream-ID: d901d9887951774e604ca970e1827afaaef9e419
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
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
[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@
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.
[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@.
[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@
[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.
[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@
[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@
[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@
[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@
[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@
[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@
[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@
