support rekeying. AFAIK this is only an ancient Sun SSH version.
If such an implementation tries to interoperate with OpenSSH, it
will eventually fail when the transport needs rekeying.
This is probably long enough to use it to download a modern SSH
implementation that lacks this problem :)
ok markus@ deraadt@
OpenBSD-Commit-ID: 228a502fee808cf8b7caee23169eb6a1ab1c331a
pre-authentication phase
OpenSSH doesn't support rekeying before authentication completes to
minimise pre-auth attack surface.
Given LoginGraceTime, MaxAuthTries and strict KEX, it would be
difficult to send enough data or packets before authentication
completes to reach a point where rekeying is required, but we'd
prefer it to be completely impossible.
So this applies the default volume/packet rekeying limits to the
pre-auth phase. If these limits are exceeded the connection will
simply be closed.
ok dtucker markus
OpenBSD-Commit-ID: 70415098db739058006e4ebd1630b6bae8cc8bf6
that shows connection information, similar to the ~I escapechar.
This is the first use of the mux extension mechanism, so it should be
both forward and backward compatible: a new client talking to an old
server will not allow the "conninfo" request to be sent, but everything
else should work seamlessly. feedback and ok djm@
OpenBSD-Commit-ID: 50f047a85da277360558cabdfed59cb66f754341
only display peer information for TCP connections including source address
and port This provides enough information to uniquely identify a connection
on the host or network.
OpenBSD-Commit-ID: aa18a4af2de41c298d1195d2566808585f8ce964
continually at runtime based on what sessions/channels are open.
Previously, ssh(1) and sshd(8) would pick a QoS value when they
were started and use it for the whole connection. This could
produce suboptimal choices for the QoS value, e.g. for multiplexed
sessions that started interactive but picked up a sftp client,
or sessions that moved large amounts of data via port forwarding.
Now the QoS value will change to the non-interactive IPQoS whenever
a "non-interactive" channel is open; basically any channel that lacks
a tty other than agent forwarding.
This is important now that the default interactive IPQoS is EF
(Expedited Forwarding), as many networks are configured to allow
only relatively small amounts of traffic of this class and they will
aggressively deprioritise the entire connection if this is exceeded.
NB. because ssh(1) and sshd(8) now change IP_TOS/IPV6_TCLASS
continually via setsockopt(), this commit requires a recent pledge(2)
change that landed recently in the OpenBSD kernel. Please ensure
you have updated to a kernel from within the last two weeks before
updating OpenSSH.
with job@ deraadt@
OpenBSD-Commit-ID: 325fc41717eecdf5e4b534bfa8d66817425b840f
struct ssh or struct packet_state; one static int escaped this rule, so move
it to struct packet_state now.
ok millert tb
OpenBSD-Commit-ID: bd6737168bf61a836ffbdc99ee4803468db90a53
compression support (which is requested as the name "zlib"). Compression
starts very early in the session. Relative early in OpenSSH lifetime, privsep
was added to sshd, and this required a shared-memory hack so the two
processes could see what was going on in the dataflow. This shared-memory
hack was soon recognized as a tremendous complexity risk, because it put libz
(which very much trusts it's memory) in a dangerous place, and a new option
("zlib@openssh.com") was added begins compression after authentication (aka
delayed-compression). That change also permitted removal of the
shared-memory hack. Despite removal from the server, the old "zlib" support
remained in the client, to allow negotiation with non-OpenSSH daemons which
lack the delayed-compression option. This commit deletes support for the
older "zlib" option in the client. It reduces our featureset in a small way,
and encourages other servers to move to a better design. The SSH protocol is
different enough that compressed-key-material attacks like BEAST are
unlikely, but who wants to take the chance? We encourage other ssh servers
who care about optional compression support to add delayed-zlib support.
(Some already do "zlib@openssh.com") ok djm markus
OpenBSD-Commit-ID: 6df986f38e4ab389f795a6e39e7c6857a763ba72
DSA remains unconverted as it will be removed within six months.
Based on patches originally from Dmitry Belyavskiy, but significantly
reworked based on feedback from Bob Beck, Joel Sing and especially
Theo Buehler (apologies to anyone I've missed).
ok tb@
OpenBSD-Commit-ID: d098744e89f1dc7e5952a6817bef234eced648b5
binaries. This step splits sshd into a listener and a session binary. More
splits are planned.
After this changes, the listener binary will validate the configuration,
load the hostkeys, listen on port 22 and manage MaxStartups only. All
session handling will be performed by a new sshd-session binary that the
listener fork+execs.
This reduces the listener process to the minimum necessary and sets us
up for future work on the sshd-session binary.
feedback/ok markus@ deraadt@
NB. if you're updating via source, please restart sshd after installing,
otherwise you run the risk of locking yourself out.
OpenBSD-Commit-ID: 43c04a1ab96cdbdeb53d2df0125a6d42c5f19934
This adds a protocol extension to improve the integrity of the SSH
transport protocol, particular in and around the initial key exchange
(KEX) phase.
Full details of the extension are in the PROTOCOL file.
with markus@
OpenBSD-Commit-ID: 2a66ac962f0a630d7945fee54004ed9e9c439f14
This attempts to hide inter-keystroke timings by sending interactive
traffic at fixed intervals (default: every 20ms) when there is only a
small amount of data being sent. It also sends fake "chaff" keystrokes
for a random interval after the last real keystroke. These are
controlled by a new ssh_config ObscureKeystrokeTiming keyword/
feedback/ok markus@
OpenBSD-Commit-ID: 02231ddd4f442212820976068c34a36e3c1b15be
This adds a pair of SSH transport protocol messages SSH2_MSG_PING/PONG
to implement a ping capability. These messages use numbers in the "local
extensions" number space and are advertised using a "ping@openssh.com"
ext-info message with a string version number of "0".
ok markus@
OpenBSD-Commit-ID: b6b3c4cb2084c62f85a8dc67cf74954015eb547f
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
Z_SYNC_FLUSH instead of Z_PARTIAL_FLUSH as the latter is not actually
specified as a valid mode for inflate(). There should be no practical change
in behaviour as the compression side ensures a flush that should make all
data available to the receiver in all cases.
repoted by lamm AT ibm.com via bz3372; ok markus
OpenBSD-Commit-ID: 67cfc1fa8261feae6d2cc0c554711c97867cc81b
client and server mainloops.
Previously the rekey timeout could expire but rekeying would not start
until a packet was sent or received. This could cause us to spin in
select() on the rekey timeout if the connection was quiet.
ok markus@
OpenBSD-Commit-ID: 4356cf50d7900f3df0a8f2117d9e07c91b9ff987
TCP connect. The connection phase of the SSH session is time-sensitive (due
to server side login grace periods) and is frequently interactive (e.g.
entering passwords). The ultimate interactive/bulk TOS/DSCP will be set after
authentication completes.
ok dtucker@
OpenBSD-Commit-ID: f31ab10d9233363a6d2c9996007083ba43a093f1
request
the change introduced a NULL deref in sshpkt_vfatal() (uses of ssh->kex after
calling ssh_packet_clear_keys())
OpenBSD-Commit-ID: 9c9a6721411461b0b1c28dc00930d7251a798484
that allows building without zlib compression and associated options. With
feedback from markus@, ok djm@
OpenBSD-Commit-ID: 44c6e1133a90fd15a3aa865bdedc53bab28b7910
some arbitrary value < 0. errno is only updated in this case. Change all
(most?) callers of syscalls to follow this better, and let's see if this
strictness helps us in the future.
OpenBSD-Commit-ID: 48081f00db7518e3b712a49dca06efc2a5428075