This adds another transport protocol extension to allow a sshd to send
SSH2_MSG_EXT_INFO during user authentication, after the server has
learned the username that is being logged in to.
This lets sshd to update the acceptable signature algoritms for public
key authentication, and allows these to be varied via sshd_config(5)
"Match" directives, which are evaluated after the server learns the
username being authenticated.
Full details in the PROTOCOL file
OpenBSD-Commit-ID: 1de7da7f2b6c32a46043d75fcd49b0cbb7db7779
This adds kex_proposal_populate_entries (and corresponding free) which
populates the KEX proposal array with dynamically allocated strings.
This replaces the previous mix of static and dynamic that has been the
source of previous leaks and bugs. Remove unused compat functions.
With & ok djm@.
OpenBSD-Commit-ID: f2f99da4aae2233cb18bf9c749320c5e040a9c7b
effective configuration without attempting to load private keys and perform
other checks. This allows usage of the option before keys have been
generated.
bz3460 feedback/ok dtucker@
OpenBSD-Commit-ID: 774504f629023fc25a559ab1d95401adb3a7fb29
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
started with one or more signals masked (sigprocmask(2) is not cleared
on fork/exec) and this could interfere with various things, e.g. the
login grace timer.
Execution environments that fail to clear the signal mask before running
sshd are clearly broken, but apparently they do exist.
Reported by Sreedhar Balasubramanian; ok dtucker@
OpenBSD-Commit-ID: 77078c0b1c53c780269fc0c416f121d05e3010ae
userspace: remove vestigial '?' cases from top-level getopt(3) loops
getopt(3) returns '?' when it encounters a flag not present in the in
the optstring or if a flag is missing its option argument. We can
handle this case with the "default" failure case with no loss of
legibility. Hence, remove all the redundant "case '?':" lines.
Prompted by dlg@. With help from dlg@ and millert@.
Link: https://marc.info/?l=openbsd-tech&m=167011979726449&w=2
ok naddy@ millert@ dlg@
OpenBSD-Commit-ID: b2f89346538ce4f5b33ab8011a23e0626a67e66e
This was added for the benefit of platforms using ssh-rand-helper to
prevent a delay on each connection as sshd reseeded itself.
ssh-random-helper is long gone, and since the re-exec happens before the
chroot the re-execed sshd can reseed itself normally. ok djm@
seed_rng will initialize OpenSSL, and some engine providers (eg Intel's
QAT) will open descriptors for their own use. bz#3483, patch from
joel.d.schuetze at intel.com, ok djm@
beneath this limit will be ignored for user and host-based authentication.
Feedback deraadt@ ok markus@
OpenBSD-Commit-ID: 187931dfc19d51873df5930a04f2d972adf1f7f1
and list_hostkey_types() that are passed to compat_pkalg_proposal(). Part of
github PR#324 from ZoltanFridrich, ok djm@
This is a roll-forward of the previous rollback now that the required
changes in compat.c have been done.
OpenBSD-Commit-ID: c7cd93730b3b9f53cdad3ae32462922834ef73eb
compat_pkalg_proposal and friends always allocate their returned strings.
Reported by Qualys.
OpenBSD-Commit-ID: 1c7a88a0d5033f42f88ab9bec58ef1cf72c81ad0
and list_hostkey_types() that are passed to compat_pkalg_proposal(). Part of
github PR#324 from ZoltanFridrich, ok djm@
OpenBSD-Commit-ID: b2f6e5f60f2bba293b831654328a8a0035ef4a1b
re-exec path - we're never going to use the result and if the operation fails
then it can prevent connections from being accepted. Reported by Aaron
Poffenberger; with / ok dtucker@
OpenBSD-Commit-ID: 44c53a43909a328e2f5ab26070fdef3594eded60
call, and terminate sshd if ppoll() returns errno==EINVAL
avoids spin in ppoll when MaxStartups > RLIMIT_NOFILE, reported by
Daniel Micay
feedback/ok deraadt
OpenBSD-Commit-ID: dbab1c24993ac977ec24d83283b8b7528f7c2c15
On some (most? all?) SysV based systems with STREAMS based ptys,
sshd could acquire a controlling terminal during pty setup when
it pushed the "ptem" module, due to what is probably a bug in
the STREAMS driver that's old enough to vote. Because it was the
privileged sshd's controlling terminal, it was not available for
the user's session, which ended up without one. This is known to
affect at least Solaris <=10, derivatives such as OpenIndiana and
several other SysV systems. See bz#245 for the backstory.
In the we past worked around that by not calling setsid in the
privileged sshd child, which meant it was not a session or process
group leader. This solved controlling terminal problem because sshd
was not eligble to acquire one, but had other side effects such as
not cleaning up helper subprocesses in the SIGALRM handler since it
was not PG leader. Recent cleanups in the signal handler uncovered
this, resulting in the LoginGraceTime timer not cleaning up privsep
unprivileged processes.
This change moves the workaround into the STREAMS pty allocation code,
by allocating a sacrificial pty to act as sshd's controlling terminal
before allocating user ptys, so those are still available for users'
sessions.
On the down side:
- this will waste a pty per ssh connection on affected platforms.
On the up side:
- it makes the process group behaviour consistent between platforms.
- it puts the workaround nearest the code that actually causes the
problem and competely out of the mainline code.
- the workaround is only activated if you use the STREAMS code. If,
say, Solaris 11 has the bug but also a working openpty() it doesn't
matter that we defined SSHD_ACQUIRES_CTTY.
- the workaround is only activated when the fist pty is allocated,
ie in the post-auth privsep monitor. This means there's no risk
of fd leaks to the unprivileged processes, and there's no effect on
sessions that do not allocate a pty.
Based on analysis and work by djm@, ok djm@
SIGALRM handler. It's no longer needed since the child will get terminated by
the SIGTERM to the process group that cleans up any auth helpers, it
simplifies the signal handler and removes the risk of a race when updating
the PID. Based on analysis by HerrSpace in github PR#289, ok djm@
OpenBSD-Commit-ID: 2be1ffa28b4051ad9e33bb4371e2ec8a31d6d663
which interferes with the new poll()-based listen loop; spotted and debugged
by anton@+deraadt@
OpenBSD-Commit-ID: f7ab8ab124f615a2e0c45fee14c38d2f2abbabbd
returns -1, eg if it was interrupted by a signal. This should prevent
the hang discovered by sthen@ wherein sshd receives a SIGHUP while it has
an unauthenticated child and goes on to a blocking read on a notify_pipe.
feedback deraadt@, ok djm@
OpenBSD-Commit-ID: 0243c1c5544fca0974dae92cd4079543a3fceaa0
keys. Allows use of certificates with private keys held in a ssh-agent.
Reported by Miles Zhou in bz3524; ok dtucker@
OpenBSD-Commit-ID: 25f5bf70003126d19162862d9eb380bf34bac22a
pselect() and mask signals while checking signal flags, umasking for pselect
and restoring afterwards. Also restore signals before sighup_restart so they
don't remain blocked after restart.
This prevents a race where a SIGTERM or SIGHUP can arrive between
checking the flag and calling select (eg if sshd is processing a
new connection) resulting in sshd not shutting down until the next
time it receives a new connection. bz#2158, with & ok djm@
OpenBSD-Commit-ID: bf85bf880fd78e00d7478657644fcda97b9a936f
location of the "moduli" file containing the groups for DH-GEX. This will
allow us to run tests against arbitrary moduli files without having to
install them. ok djm@
OpenBSD-Commit-ID: 8df99d60b14ecaaa28f3469d01fc7f56bff49f66
works on OpenBSD it can cause problems on other platforms. From kircherlike
at outlook.com via bz#3259, ok djm@
OpenBSD-Commit-ID: 3e241d7ac1ee77e3de3651780b5dc47b283a7668
options which provide more fine grained MaxStartups limits. Man page help
jmc@, feedback & ok djm@
OpenBSD-Commit-ID: e2f68664e3d02c0895b35aa751c48a2af622047b
exchange method based on Streamlined NTRU Prime (coupled with X25519).
The previous sntrup4591761x25519-sha512@tinyssh.org method is
replaced with sntrup761x25519-sha512@openssh.com. Per the authors,
sntrup4591761 was replaced almost two years ago by sntrup761.
The sntrup761 implementaion, like sntrup4591761 before it, is public
domain code extracted from the SUPERCOP cryptography benchmark
suite (https://bench.cr.yp.to/supercop.html).
Thanks for Daniel J Bernstein for guidance on algorithm selection.
Patch from Tobias Heider; feedback & ok markus@ and myself
(note this both the updated method and the one that it replaced are
disabled by default)
OpenBSD-Commit-ID: 2bf582b772d81ee24e911bb6f4b2aecfd39338ae
The log calls are themselves now macros, and preprocessor directives inside
macro arguments are undefined behaviour which some compilers (eg old GCCs)
choke on. It also makes the code tidier. ok deraadt@
OpenBSD-Commit-ID: cc12a9029833d222043aecd252d654965c351a69
stdout and/or stderr to /dev/null. Factor all these out to a single
stdfd_devnull() function that allows selection of which of these to redirect.
ok markus@
OpenBSD-Commit-ID: 3033ba5a4c47cacfd5def020d42cabc52fad3099
FIDO2 supports a notion of "user verification" where the user is
required to demonstrate their identity to the token before particular
operations (e.g. signing). Typically this is done by authenticating
themselves using a PIN that has been set on the token.
This adds support for generating and using user verified keys where
the verification happens via PIN (other options might be added in the
future, but none are in common use now). Practically, this adds
another key generation option "verify-required" that yields a key that
requires a PIN before each authentication.
feedback markus@ and Pedro Martelletto; ok markus@
OpenBSD-Commit-ID: 57fd461e4366f87c47502c5614ec08573e6d6a15
djm@openbsd.org
Darren Tucker
guenther@openbsd.org
dtucker@openbsd.org
millert@openbsd.org
cheloha@openbsd.org
deraadt@openbsd.org
markus@openbsd.org