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.
OpenBSD-Commit-ID: 2a66ac962f0a630d7945fee54004ed9e9c439f14
Approved by: so (implicit)
Obtained from: https://anongit.mindrot.org/openssh.git/patch/?id=1edb00c58f8a6875fad6a497aa2bacf37f9e6cd5
Security: CVE-2023-48795
Excerpts from the release notes:
Potentially incompatible changes
--------------------------------
* ssh-keygen(1): generate Ed25519 keys by default.
[NOTE: This change was already merged into FreeBSD.]
* sshd(8): the Subsystem directive now accurately preserves quoting of
subsystem commands and arguments.
New features
------------
* ssh(1): add keystroke timing obfuscation to the client.
* ssh(1), sshd(8): Introduce a transport-level ping facility.
* sshd(8): allow override of Sybsystem directives in sshd Match blocks.
Full release notes at https://www.openssh.com/txt/release-9.5
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Excerpts from the release notes:
* ssh-agent(1): PKCS#11 modules must now be specified by their full
paths. Previously dlopen(3) could search for them in system
library directories.
* ssh(1): allow forwarding Unix Domain sockets via ssh -W.
* ssh(1): add support for configuration tags to ssh(1).
This adds a ssh_config(5) "Tag" directive and corresponding
"Match tag" predicate that may be used to select blocks of
configuration similar to the pf.conf(5) keywords of the same
name.
* ssh(1): add a "match localnetwork" predicate. This allows matching
on the addresses of available network interfaces and may be used to
vary the effective client configuration based on network location.
* ssh-agent(1): improve isolation between loaded PKCS#11 modules
by running separate ssh-pkcs11-helpers for each loaded provider.
* ssh-agent(1), ssh(1): improve defences against invalid PKCS#11
modules being loaded by checking that the requested module
contains the required symbol before loading it.
* ssh(1): don't incorrectly disable hostname canonicalization when
CanonicalizeHostname=yes and ProxyJump was expicitly set to
"none". bz3567
Full release notes at https://www.openssh.com/txt/release-9.4
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
This release fixes a number of security bugs and has minor new
features and bug fixes. Security fixes, from the release notes
(https://www.openssh.com/txt/release-9.3):
This release contains fixes for a security problem and a memory
safety problem. The memory safety problem is not believed to be
exploitable, but we report most network-reachable memory faults as
security bugs.
* ssh-add(1): when adding smartcard keys to ssh-agent(1) with the
per-hop destination constraints (ssh-add -h ...) added in OpenSSH
8.9, a logic error prevented the constraints from being
communicated to the agent. This resulted in the keys being added
without constraints. The common cases of non-smartcard keys and
keys without destination constraints are unaffected. This problem
was reported by Luci Stanescu.
* ssh(1): Portable OpenSSH provides an implementation of the
getrrsetbyname(3) function if the standard library does not
provide it, for use by the VerifyHostKeyDNS feature. A
specifically crafted DNS response could cause this function to
perform an out-of-bounds read of adjacent stack data, but this
condition does not appear to be exploitable beyond denial-of-
service to the ssh(1) client.
The getrrsetbyname(3) replacement is only included if the system's
standard library lacks this function and portable OpenSSH was not
compiled with the ldns library (--with-ldns). getrrsetbyname(3) is
only invoked if using VerifyHostKeyDNS to fetch SSHFP records. This
problem was found by the Coverity static analyzer.
Sponsored by: The FreeBSD Foundation
Release notes are available at https://www.openssh.com/txt/release-9.1
9.1 contains fixes for three minor memory safety problems; these have
lready been merged to the copy of OpenSSH 9.0 that is in the FreeBSD base
system.
Some highlights copied from the release notes:
Potentially-incompatible changes
--------------------------------
* ssh(1), sshd(8): SetEnv directives in ssh_config and sshd_config
are now first-match-wins to match other directives. Previously
if an environment variable was multiply specified the last set
value would have been used. bz3438
* ssh-keygen(8): ssh-keygen -A (generate all default host key types)
will no longer generate DSA keys, as these are insecure and have
not been used by default for some years.
New features
------------
* ssh(1), sshd(8): add a RequiredRSASize directive to set a minimum
RSA key length. Keys below this length will be ignored for user
authentication and for host authentication in sshd(8).
* sftp-server(8): add a "users-groups-by-id@openssh.com" extension
request that allows the client to obtain user/group names that
correspond to a set of uids/gids.
* sftp(1): use "users-groups-by-id@openssh.com" sftp-server
extension (when available) to fill in user/group names for
directory listings.
* sftp-server(8): support the "home-directory" extension request
defined in draft-ietf-secsh-filexfer-extensions-00. This overlaps
a bit with the existing "expand-path@openssh.com", but some other
clients support it.
* ssh-keygen(1), sshd(8): allow certificate validity intervals,
sshsig verification times and authorized_keys expiry-time options
to accept dates in the UTC time zone in addition to the default
of interpreting them in the system time zone. YYYYMMDD and
YYMMDDHHMM[SS] dates/times will be interpreted as UTC if suffixed
with a 'Z' character.
Also allow certificate validity intervals to be specified in raw
seconds-since-epoch as hex value, e.g. -V 0x1234:0x4567890. This
is intended for use by regress tests and other tools that call
ssh-keygen as part of a CA workflow. bz3468
* sftp(1): allow arguments to the sftp -D option, e.g. sftp -D
"/usr/libexec/sftp-server -el debug3"
* ssh-keygen(1): allow the existing -U (use agent) flag to work
with "-Y sign" operations, where it will be interpreted to require
that the private keys is hosted in an agent; bz3429
MFC after: 2 weeks
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
After we moved to git $FreeBSD$ is no longer expanded and serves no
purpose. Remove them from OpenSSH to reduce diffs against upstream.
Sponsored by: The FreeBSD Foundation
Release notes are available at https://www.openssh.com/txt/release-8.9
Some highlights:
* ssh(1), sshd(8), ssh-add(1), ssh-agent(1): add a system for
restricting forwarding and use of keys added to ssh-agent(1)
* ssh(1), sshd(8): add the sntrup761x25519-sha512@openssh.com hybrid
ECDH/x25519 + Streamlined NTRU Prime post-quantum KEX to the
default KEXAlgorithms list (after the ECDH methods but before the
prime-group DH ones). The next release of OpenSSH is likely to
make this key exchange the default method.
* sshd(8), portable OpenSSH only: this release removes in-built
support for MD5-hashed passwords. If you require these on your
system then we recommend linking against libxcrypt or similar.
Future deprecation notice
=========================
A near-future release of OpenSSH will switch scp(1) from using the
legacy scp/rcp protocol to using SFTP by default.
Legacy scp/rcp performs wildcard expansion of remote filenames (e.g.
"scp host:* .") through the remote shell. This has the side effect of
requiring double quoting of shell meta-characters in file names
included on scp(1) command-lines, otherwise they could be interpreted
as shell commands on the remote side.
MFC after: 1 month
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Some notable changes, from upstream's release notes:
- sshd(8): Remove support for obsolete "host/port" syntax.
- ssh(1): When prompting whether to record a new host key, accept the key
fingerprint as a synonym for "yes".
- ssh-keygen(1): when acting as a CA and signing certificates with an RSA
key, default to using the rsa-sha2-512 signature algorithm.
- ssh(1), sshd(8), ssh-keygen(1): this release removes the "ssh-rsa"
(RSA/SHA1) algorithm from those accepted for certificate signatures.
- ssh-sk-helper(8): this is a new binary. It is used by the FIDO/U2F
support to provide address-space isolation for token middleware
libraries (including the internal one).
- ssh(1): this release enables UpdateHostkeys by default subject to some
conservative preconditions.
- scp(1): this release changes the behaviour of remote to remote copies
(e.g. "scp host-a:/path host-b:") to transfer through the local host
by default.
- scp(1): experimental support for transfers using the SFTP protocol as
a replacement for the venerable SCP/RCP protocol that it has
traditionally used.
Additional integration work is needed to support FIDO/U2F in the base
system.
Deprecation Notice
------------------
OpenSSH will disable the ssh-rsa signature scheme by default in the
next release.
Reviewed by: imp
MFC after: 1 month
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D29985
This completely removes client-side support for the SSH 1 protocol,
which was already disabled in 12 but is still enabled in 11. For that
reason, we will not be able to merge 7.6p1 or newer back to 11.
Adjust notification points slightly to catch all auth failures,
rather than just the ones caused by bad usernames.
Modify notification point for bad usernames to send new type of
BLACKLIST_BAD_USER. (Support in libblacklist will be forthcoming soon.)
Add guards to allow library headers to expose the enum of action values.
Reviewed by: des
Approved by: des
Sponsored by: The FreeBSD Foundation
Change the calls to of blacklist_init() and blacklist_notify to be
macros defined in the blacklist_client.h file. This avoids
the need for #ifdef USE_BLACKLIST / #endif except in the
blacklist.c file.
Remove redundent initialization attempts from within
blacklist_notify - everything always goes through
blacklistd_init().
Added UseBlacklist option to sshd, which defaults to off.
To enable the functionality, use '-o UseBlacklist=yes' on
the command line, or uncomment in the sshd_config file.
Reviewed by: des
Approved by: des
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D7051
This change has functional impact, and other concerns raised
by the OpenSSH maintainer.
Requested by: des
PR: 210479 (related)
Approved by: re (marius)
Sponsored by: The FreeBSD Foundation
Reviewed by: rpaulo
Approved by: rpaulo (earlier version of changes)
Relnotes: YES
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5915
$FreeBSD$ tags and man page dates.
Add a post-merge script which reapplies these changes.
Run both scripts to normalize the existing code base. As a result, many
files which should have had $FreeBSD$ tags but didn't now have them.
Partly rewrite the upgrade instructions and remove the now outdated
list of tricks.
the bandwidth of long fat pipes (i.e. 100Mbps+ trans-oceanic or
trans-continental links). Bandwidth-delay products up to 64MB are
supported.
Also add support (not compiled by default) for the None cypher. The
None cypher can only be enabled on non-interactive sessions (those
without a pty where -T was not used) and must be enabled in both
the client and server configuration files and on the client command
line. Additionally, the None cypher will only be activated after
authentication is complete. To enable the None cypher you must add
-DNONE_CIPHER_ENABLED to CFLAGS via the make command line or in
/etc/make.conf.
This code is a style(9) compliant version of these features extracted
from the patches published at:
http://www.psc.edu/networking/projects/hpn-ssh/
Merging this patch has been a collaboration between me and Bjoern.
Reviewed by: bz
Approved by: re (kib), des (maintainer)
I have worked hard to reduce diffs against the vendor branch. One
notable change in that respect is that we no longer prefer DSA over
RSA - the reasons for doing so went away years ago. This may cause
some surprises, as ssh will warn about unknown host keys even for
hosts whose keys haven't changed.
MFC after: 6 weeks
