[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]
remove a debug() that pollutes stderr on client connecting to a server
in debug mode (channel_close_fds is called transitively from the session
code post-fork); bz#1719, ok dtucker
[channels.c]
Fix a trio of bugs in the local/remote window calculation for datagram
data channels (i.e. TunnelForward):
Calculate local_consumed correctly in channel_handle_wfd() by measuring
the delta to buffer_len(c->output) from when we start to when we finish.
The proximal problem here is that the output_filter we use in portable
modified the length of the dequeued datagram (to futz with the headers
for !OpenBSD).
In channel_output_poll(), don't enqueue datagrams that won't fit in the
peer's advertised packet size (highly unlikely to ever occur) or which
won't fit in the peer's remaining window (more likely).
In channel_input_data(), account for the 4-byte string header in
datagram packets that we accept from the peer and enqueue in c->output.
report, analysis and testing 2/3 cases from wierbows AT us.ibm.com;
"looks good" markus@
[auth-rsa.c channels.c jpake.c key.c misc.c misc.h monitor.c]
[packet.c ssh-rsa.c]
implement a timing_safe_cmp() function to compare memory without leaking
timing information by short-circuiting like memcmp() and use it for
some of the more sensitive comparisons (though nothing high-value was
readily attackable anyway); "looks ok" markus@
[channels.c session.c]
bz#1750: fix requirement for /dev/null inside ChrootDirectory for
internal-sftp accidentally introduced in r1.253 by removing the code
that opens and dup /dev/null to stderr and modifying the channels code
to read stderr but discard it instead; ok markus@
[channels.c mux.c readconf.c readconf.h ssh.h]
bz#1327: remove hardcoded limit of 100 permitopen clauses and port
forwards per direction; ok markus@ stevesk@
[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]
fake local addr:port when stdio fowarding as some servers (Tectia at
least) validate that they are well-formed;
reported by imorgan AT nas.nasa.gov
ok dtucker
[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@
[sshconnect2.c channels.c sshconnect.c]
Set close-on-exec on various descriptors so they don't get leaked to
child processes. bz #1643, patch from jchadima at redhat, ok deraadt.
[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@
set IPV6_V6ONLY for local forwarding with GatwayPorts=yes. Unify
setting IPV6_V6ONLY behind a new function misc.c:sock_set_v6only()
report and fix from jan.kratochvil AT redhat.com
the pty master on Solaris, since it never succeeds and can hang if large
amounts of data is sent to the slave (eg a copy-paste). Based on a patch
originally from Doke Scott, ok djm@
[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@
[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@
[channels.c]
call channel destroy callbacks on receipt of open failure messages.
fixes client hangs when connecting to a server that has MaxSessions=0
set spotted by imorgan AT nas.nasa.gov; ok markus@
[channels.c servconf.c]
channel_print_adm_permitted_opens() should deal with all the printing
for that config option. suggested by markus@; ok markus@ djm@
dtucker@
[packet.c scp.c serverloop.c sftp-client.c ssh-agent.c ssh-keyscan.c]
[sshd.c] Explicitly handle EWOULDBLOCK wherever we handle EAGAIN, on
some platforms (HP nonstop) it is a distinct errno;
bz#1467 reported by sconeu AT yahoo.com; ok dtucker@
[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
[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.
[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@
[sshd.c channels.h channels.c log.c servconf.c log.h servconf.h sshd.8]
Add extended test mode (-T) and connection parameters for test mode (-C).
-T causes sshd to write its effective configuration to stdout and exit.
-C causes any relevant Match rules to be applied before output. The
combination allows tesing of the parser and config files. ok deraadt djm
[channels.c]
error-fd race: don't enable the error fd in the select bitmask
for channels with both in- and output closed, since the channel
will go away before we call select();
report, lots of debugging help and ok djm@
[channels.c channels.h clientloop.c serverloop.c]
Try additional addresses when connecting to a port forward destination
whose DNS name resolves to more than one address. The previous behaviour
was to try the first address and give up.
Reported by stig AT venaas.com in bz#343
great feedback and ok markus@
[auth-options.c auth1.c channels.c channels.h clientloop.c gss-serv.c]
[monitor.c monitor_wrap.c nchan.c servconf.c serverloop.c session.c]
[ssh.c sshd.c]
Implement a channel success/failure status confirmation callback
mechanism. Each channel maintains a queue of callbacks, which will
be drained in order (RFC4253 guarantees confirm messages are not
reordered within an channel).
Also includes a abandonment callback to clean up if a channel is
closed without sending confirmation messages. This probably
shouldn't happen in compliant implementations, but it could be
abused to leak memory.
ok markus@ (as part of a larger diff)
[bufaux.c buffer.h channels.c packet.c packet.h]
avoid extra malloc/copy/free when receiving data over the net;
~10% speedup for localhost-scp; ok djm@
[channels.c]
When we added support for specified bind addresses for port forwards, we
added a quirk SSH_OLD_FORWARD_ADDR. There is a bug in our handling of
this for -L port forwards that causes the client to listen on both v4
and v6 addresses when connected to a server with this quirk, despite
having set 0.0.0.0 as a bind_address.
report and patch from Jan.Pechanec AT Sun.COM; ok dtucker@
[servconf.c canohost.c misc.c channels.c sshconnect.c misc.h ssh-keyscan.c
sshd.c]
Add a small helper function to consistently handle the EAI_SYSTEM error
code of getaddrinfo. Prompted by vgiffin at apple com via bz #1417.
ok markus@ stevesk@
when closing a tty session when a background process still holds tty
fds open. Great detective work and patch by Marc Aurele La France,
slightly tweaked by me; ok dtucker@
[channels.c compat.c compat.h]
bz #1019: some ssh.com versions apparently can't cope with the
remote port forwarding bind_address being a hostname, so send
them an address for cases where they are not explicitly
specified (wildcard or localhost bind). reported by daveroth AT
acm.org; ok dtucker@ deraadt@
[channels.c session.c]
normalise some inconsistent (but harmless) NULL pointer checks
spotted by the Stanford SATURN tool, via Isil Dillig;
ok markus@ deraadt@
[canohost.c channels.c cipher-acss.c defines.h dns.c gss-genr.c]
[gss-serv-krb5.c gss-serv.c log.h loginrec.c logintest.c readconf.c]
[servconf.c ssh-keygen.c ssh-keyscan.c ssh-keysign.c ssh-rand-helper.c]
[ssh.c sshconnect.c sshd.c openbsd-compat/bindresvport.c]
[openbsd-compat/bsd-arc4random.c openbsd-compat/bsd-misc.c]
[openbsd-compat/getrrsetbyname.c openbsd-compat/glob.c]
[openbsd-compat/mktemp.c openbsd-compat/port-linux.c]
[openbsd-compat/port-tun.c openbsd-compat/readpassphrase.c]
[openbsd-compat/setproctitle.c openbsd-compat/xmmap.c]
make the portable tree compile again - sprinkle unistd.h and string.h
back in. Don't redefine __unused, as it turned out to be used in
headers on Linux, and replace its use in auth-pam.c with ARGSUSED
[channels.c channels.h servconf.c servconf.h sshd_config.5]
Make PermitOpen take a list of permitted ports and act more like most
other keywords (ie the first match is the effective setting). This
also makes it easier to override a previously set PermitOpen. ok djm@
[channels.c channels.h servconf.c sshd_config.5]
Add PermitOpen directive to sshd_config which is equivalent to the
"permitopen" key option. Allows server admin to allow TCP port
forwarding only two specific host/port pairs. Useful when combined
with Match.
If permitopen is used in both sshd_config and a key option, both
must allow a given connection before it will be permitted.
Note that users can still use external forwarders such as netcat,
so to be those must be controlled too for the limits to be effective.
Feedback & ok djm@, man page corrections & ok jmc@.
[clientloop.c ssh.1 ssh.c channels.c ssh_config.5 readconf.h session.c
channels.h readconf.c]
add ExitOnForwardFailure: terminate the connection if ssh(1)
cannot set up all requested dynamic, local, and remote port
forwardings. ok djm, dtucker, stevesk, jmc
4.3.3 ML3 or so, the AIX pty layer starting passing zero-length writes
on the pty slave as zero-length reads on the pty master, which sshd
interprets as the descriptor closing. Since most things don't do zero
length writes this rarely matters, but occasionally it happens, and when
it does the SSH pty session appears to hang, so we add a special case for
this condition. ok djm@
[buffer.c buffer.h channels.c]
Fix condition where we could exit with a fatal error when an input
buffer became too large and the remote end had advertised a big window.
The problem was a mismatch in the backoff math between the channels code
and the buffer code, so make a buffer_check_alloc() function that the
channels code can use to propsectivly check whether an incremental
allocation will succeed. bz #1131, debugged with the assistance of
cove AT wildpackets.com; ok dtucker@ deraadt@
[buffer.c channels.c deattack.c misc.c scp.c session.c sftp-client.c]
[sftp-server.c ssh-agent.c ssh-rsa.c xmalloc.c xmalloc.h auth-pam.c]
[uidswap.c]
change OpenSSH's xrealloc() function from being xrealloc(p, new_size)
to xrealloc(p, new_nmemb, new_itemsize).
realloc is particularly prone to integer overflows because it is
almost always allocating "n * size" bytes, so this is a far safer
API; ok deraadt@
[auth-bsdauth.c auth-skey.c auth.c auth2-chall.c channels.c]
[clientloop.c deattack.c gss-genr.c kex.c key.c misc.c moduli.c]
[monitor.c monitor_wrap.c packet.c scard.c sftp-server.c ssh-agent.c]
[ssh-keyscan.c ssh.c sshconnect.c sshconnect2.c sshd.c uuencode.c]
[xmalloc.c xmalloc.h]
introduce xcalloc() and xasprintf() failure-checked allocations
functions and use them throughout openssh
xcalloc is particularly important because malloc(nmemb * size) is a
dangerous idiom (subject to integer overflow) and it is time for it
to die
feedback and ok deraadt@
[channels.c monitor.c session.c session.h ssh-agent.c ssh-keygen.c]
[ssh-rsa.c ssh.c sshlogin.c]
annoying spacing fixes getting in the way of real diffs
[channels.c channels.h session.c]
make sure protocol messages for internal channels are ignored.
allow adjust messages for non-open channels; with and ok djm@
[auth-options.c auth-options.h channels.c channels.h clientloop.c]
[misc.c misc.h readconf.c readconf.h scp.c servconf.c servconf.h]
[serverloop.c sftp.c ssh.1 ssh.c ssh_config ssh_config.5 sshconnect.c]
[sshconnect.h sshd.8 sshd_config sshd_config.5]
Add support for tun(4) forwarding over OpenSSH, based on an idea and
initial channel code bits by markus@. This is a simple and easy way to
use OpenSSH for ad hoc virtual private network connections, e.g.
administrative tunnels or secure wireless access. It's based on a new
ssh channel and works similar to the existing TCP forwarding support,
except that it depends on the tun(4) network interface on both ends of
the connection for layer 2 or layer 3 tunneling. This diff also adds
support for LocalCommand in the ssh(1) client.
ok djm@, markus@, jmc@ (manpages), tested and discussed with others
[channels.c]
bz #1076 set SO_REUSEADDR on X11 forwarding listner sockets, preventing
bind() failure when a previous connection's listeners are in TIME_WAIT,
reported by plattner AT inf.ethz.ch; ok dtucker@
