ssh->kex and factor out the banner exchange. This eliminates some common code
from the client and server.
Also be more strict about handling \r characters - these should only
be accepted immediately before \n (pointed out by Jann Horn).
Inspired by a patch from Markus Schmidt.
(lots of) feedback and ok markus@
OpenBSD-Commit-ID: 1cc7885487a6754f63641d7d3279b0941890275b
Don't call OpenSSL_add_all_algorithms() unless OpenSSL actually
supports it.
Move all libcrypto initialisation to a single function, and call that
from seed_rng() that is called early in each tool's main().
Prompted by patch from Rosen Penev
loading the default hostkeys. Hostkeys explicitly specified in the
configuration or on the command-line are still reported as errors, and
failure to load at least one host key remains a fatal error.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Based on patch from Dag-Erling Smørgrav via
https://github.com/openssh/openssh-portable/pull/103
ok markus@
OpenBSD-Commit-ID: ffc2e35a75d1008effaf05a5e27425041c27b684
OIDs by calling ssh_gssapi_prepare_supported_oids() regardless of whether
GSSAPI authentication is enabled in the main config.
This avoids sandbox violations for configurations that enable GSSAPI
auth later, e.g.
Match user djm
GSSAPIAuthentication yes
bz#2107; ok dtucker@
OpenBSD-Commit-ID: a5dd42d87c74e27cfb712b15b0f97ab20e0afd1d
causes double-free under some circumstances.
--
date: 2018/07/31 03:07:24; author: djm; state: Exp; lines: +33 -18; commitid: f7g4UI8eeOXReTPh;
fix some memory leaks spotted by Coverity via Jakub Jelen in bz#2366
feedback and ok dtucker@
OpenBSD-Commit-ID: 1e77547f60fdb5e2ffe23e2e4733c54d8d2d1137
In ssh, when an agent fails to return a RSA-SHA2 signature when
requested and falls back to RSA-SHA1 instead, retry the signature to
ensure that the public key algorithm sent in the SSH_MSG_USERAUTH
matches the one in the signature itself.
In sshd, strictly enforce that the public key algorithm sent in the
SSH_MSG_USERAUTH message matches what appears in the signature.
Make the sshd_config PubkeyAcceptedKeyTypes and
HostbasedAcceptedKeyTypes options control accepted signature algorithms
(previously they selected supported key types). This allows these
options to ban RSA-SHA1 in favour of RSA-SHA2.
Add new signature algorithms "rsa-sha2-256-cert-v01@openssh.com" and
"rsa-sha2-512-cert-v01@openssh.com" to force use of RSA-SHA2 signatures
with certificate keys.
feedback and ok markus@
OpenBSD-Commit-ID: c6e9f6d45eed8962ad502d315d7eaef32c419dde
establishes a minimum time for each failed authentication attempt (5ms) and
adds a per-user constant derived from a host secret (0-4ms). Based on work
by joona.kannisto at tut.fi, ok markus@ djm@.
OpenBSD-Commit-ID: b7845b355bb7381703339c8fb0e57e81a20ae5ca
remove the legacy one.
Includes a fairly big refactor of auth2-pubkey.c to retain less state
between key file lines.
feedback and ok markus@
OpenBSD-Commit-ID: dece6cae0f47751b9892080eb13d6625599573df
The code required to support it is quite invasive to the mainline
code that is synced with upstream and is an ongoing maintenance burden.
Both the hardware and software are literal museum pieces these days and
we could not find anyone still running OpenSSH on one.
The signal handlers from the original ssh1 code on which OpenSSH
is based assume unreliable signals and reinstall their handlers.
Since OpenBSD (and pretty much every current system) has reliable
signals this is not needed. In the unlikely even that -portable
is still being used on such systems we will deal with it in the
compat layer. ok deraadt@
OpenBSD-Commit-ID: f53a1015cb6908431b92116130d285d71589612c
Fix a logic bug in sshd_exchange_identification which
prevented clients using major protocol version 2 from connecting to the
server. ok millert@
OpenBSD-Commit-ID: 8668dec04586e27f1c0eb039ef1feb93d80a5ee9
Drop compatibility hacks for some ancient SSH
implementations, including ssh.com <=2.* and OpenSSH <= 3.*.
These versions were all released in or before 2001 and predate the
final SSH RFCs. The hacks in question aren't necessary for RFC-
compliant SSH implementations.
ok markus@
OpenBSD-Commit-ID: 4be81c67db57647f907f4e881fb9341448606138
unbreak support for clients that advertise a protocol
version of "1.99" (indicating both v2 and v1 support). Busted by me during
SSHv1 purge in r1.358; bz2810, ok dtucker
OpenBSD-Commit-ID: e8f9c2bee11afc16c872bb79d6abe9c555bd0e4b
avoid modifying pw->pw_passwd; let endpwent() clean up
for us, but keep a scrubbed copy; bz2777, ok dtucker@
OpenBSD-Commit-ID: 715afc0f59c6b82c4929a73279199ed241ce0752
fix problem in configuration parsing when in config dump mode
(sshd -T) without providing a full connection specification (sshd -T -C ...)
spotted by bluhm@
OpenBSD-Commit-ID: 7125faf5740eaa9d3a2f25400a0bc85e94e28b8f
When doing a config test with sshd -T, only require the
attributes that are actually used in Match criteria rather than (an
incomplete list of) all criteria. ok djm@, man page help jmc@
OpenBSD-Commit-ID: b4e773c4212d3dea486d0259ae977551aab2c1fc
add a "rdomain" criteria for the sshd_config Match
keyword to allow conditional configuration that depends on which rdomain(4) a
connection was recevied on. ok markus@
Upstream-ID: 27d8fd5a3f1bae18c9c6e533afdf99bff887a4fb
add sshd_config RDomain keyword to place sshd and the
subsequent user session (including the shell and any TCP/IP forwardings) into
the specified rdomain(4)
ok markus@
Upstream-ID: be2358e86346b5cacf20d90f59f980b87d1af0f5
Add optional rdomain qualifier to sshd_config's
ListenAddress option to allow listening on a different rdomain(4), e.g.
ListenAddress 0.0.0.0 rdomain 4
Upstream-ID: 24b6622c376feeed9e9be8b9605e593695ac9091
replace statically-sized arrays in ServerOptions with
dynamic ones managed by xrecallocarray, removing some arbitrary (though
large) limits and saving a bit of memory; "much nicer" markus@
Upstream-ID: 1732720b2f478fe929d6687ac7b0a97ff2efe9d2
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
remove post-SSHv1 removal dead code from rsa.c and merge
the remaining bit that it still used into ssh-rsa.c; ok markus
Upstream-ID: ac8a048d24dcd89594b0052ea5e3404b473bfa2f
If running with privsep (mandatory now) as a non-privileged user, we
don't chroot or change to an unprivileged user however we still checked
the existence of the user and directory. Don't do those checks if we're
not going to use them. Based in part on a patch from Lionel Fourquaux
via Corinna Vinschen, ok djm@
Fix segfault when sshd attempts to load RSA1 keys (can
only happen when protocol v.1 support is enabled for the client). Reported by
Jakub Jelen in bz#2686; ok dtucker
Upstream-ID: 8fdaec2ba4b5f65db1d094f6714ce64b25d871d7
Restore \r\n newline sequence for server ident string. The CR
got lost in the flensing of SSHv1. Pointed out by Stef Bon
Upstream-ID: 5333fd43ce5396bf5999496096fac5536e678fac
Make ssh_packet_set_rekey_limits take u32 for the number of
seconds until rekeying (negative values are rejected at config parse time).
This allows the removal of some casts and a signed vs unsigned comparison
warning.
rekey_time is cast to int64 for the comparison which is a no-op
on OpenBSD, but should also do the right thing in -portable on
anything still using 32bit time_t (until the system time actually
wraps, anyway).
some early guidance deraadt@, ok djm@
Upstream-ID: c9f18613afb994a07e7622eb326f49de3d123b6c
log connections dropped in excess of MaxStartups at
verbose LogLevel; bz#2613 based on diff from Tomas Kuthan; ok dtucker@
Upstream-ID: 703ae690dbf9b56620a6018f8a3b2389ce76d92b
Unlink PidFile on SIGHUP and always recreate it when the
new sshd starts. Regression tests (and possibly other things) depend on the
pidfile being recreated after SIGHUP, and unlinking it means it won't contain
a stale pid if sshd fails to restart. ok djm@ markus@
Upstream-ID: 132dd6dda0c77dd49d2f15b2573b5794f6160870
On startup, check to see if sshd is already daemonized
and if so, skip the call to daemon() and do not rewrite the PidFile. This
means that when sshd re-execs itself on SIGHUP the process ID will no longer
change. Should address bz#2641. ok djm@ markus@.
Upstream-ID: 5ea0355580056fb3b25c1fd6364307d9638a37b9
Add a call to RAND_poll() to ensure than more than pid+time gets
stirred into child processes states. Prompted by analysis from Jann
Horn at Project Zero. ok dtucker@
Remove support for pre-authentication compression. Doing
compression early in the protocol probably seemed reasonable in the 1990s,
but today it's clearly a bad idea in terms of both cryptography (cf. multiple
compression oracle attacks in TLS) and attack surface.
Moreover, to support it across privilege-separation zlib needed
the assistance of a complex shared-memory manager that made the
required attack surface considerably larger.
Prompted by Guido Vranken pointing out a compiler-elided security
check in the shared memory manager found by Stack
(http://css.csail.mit.edu/stack/); ok deraadt@ markus@
NB. pre-auth authentication has been disabled by default in sshd
for >10 years.
Upstream-ID: 32af9771788d45a0779693b41d06ec199d849caf
fix uninitialised optlen in getsockopt() call; harmless
on Unix/BSD but potentially crashy on Cygwin. Reported by James Slepicka ok
deraadt@
Upstream-ID: 1987ccee508ba5b18f016c85100d7ac3f70ff965
remove UseLogin option and support for having /bin/login
manage login sessions; ok deraadt markus dtucker
Upstream-ID: bea7213fbf158efab7e602d9d844fba4837d2712
Remove more SSH1 server code: * Drop sshd's -k option. *
Retire configuration keywords that only apply to protocol 1, as well as the
"protocol" keyword. * Remove some related vestiges of protocol 1 support.
ok markus@
Upstream-ID: 9402f82886de917779db12f8ee3f03d4decc244d
Fix bug introduced in rev 1.467 which causes
"buffer_get_bignum_ret: incomplete message" errors when built with WITH_SSH1
and run such that no Protocol 1 ephemeral host key is generated (eg "Protocol
2", no SSH1 host key supplied). Reported by rainer.laatsch at t-online.de,
ok deraadt@
Upstream-ID: aa6b132da5c325523aed7989cc5a320497c919dc
add support for additional fixed DH groups from
draft-ietf-curdle-ssh-kex-sha2-03
diffie-hellman-group14-sha256 (2K group)
diffie-hellman-group16-sha512 (4K group)
diffie-hellman-group18-sha512 (8K group)
based on patch from Mark D. Baushke and Darren Tucker
ok markus@
Upstream-ID: ac00406ada4f0dfec41585ca0839f039545bc46f
fix signed/unsigned errors reported by clang-3.7; add
sshbuf_dup_string() to replace a common idiom of strdup(sshbuf_ptr()) with
better safety checking; feedback and ok markus@
Upstream-ID: 71f926d9bb3f1efed51319a6daf37e93d57c8820
refactor canohost.c: move functions that cache results closer
to the places that use them (authn and session code). After this, no state is
cached in canohost.c
feedback and ok markus@
Upstream-ID: 5f2e4df88d4803fc8ec59ec53629105e23ce625e
Add a function to enable security-related malloc_options.
With and ok deraadt@, something similar has been in the snaps for a while.
Upstream-ID: 43a95523b832b7f3b943d2908662191110c380ed
Allow RekeyLimits in excess of 4G up to 2**63 bits
(limited by the return type of scan_scaled). Part of bz#2521, ok djm.
Upstream-ID: 13bea82be566b9704821b1ea05bf7804335c7979
implement SHA2-{256,512} for RSASSA-PKCS1-v1_5 signatures
(user and host auth) based on draft-rsa-dsa-sha2-256-03.txt and
draft-ssh-ext-info-04.txt; with & ok djm@
Upstream-ID: cf82ce532b2733e5c4b34bb7b7c94835632db309
always call privsep_preauth_child() regardless of whether
sshd was started by root; it does important priming before sandboxing and
failing to call it could result in sandbox violations later; ok markus@
Upstream-ID: c8a6d0d56c42f3faab38460dc917ca0d1705d383
Plug minor memory leaks when options are used more than
once. bz#2182, patch from Tiago Cunha, ok deraadt djm
Upstream-ID: 5b84d0401e27fe1614c10997010cc55933adb48e
Allow ssh_config and sshd_config kex parameters options be
prefixed by a '+' to indicate that the specified items be appended to the
default rather than replacing it.
approach suggested by dtucker@, feedback dlg@, ok markus@
Upstream-ID: 0f901137298fc17095d5756ff1561a7028e8882a
Turn off DSA by default; add HostKeyAlgorithms to the
server and PubkeyAcceptedKeyTypes to the client side, so it still can be
tested or turned back on; feedback and ok djm@
Upstream-ID: 8450a9e6d83f80c9bfed864ff061dfc9323cec21
turn off 1024 bit diffie-hellman-group1-sha1 key
exchange method (already off in server, this turns it off in the client by
default too) ok dtucker@
Upstream-ID: f59b88f449210ab7acf7d9d88f20f1daee97a4fa
add AuthorizedPrincipalsCommand that allows getting
authorized_principals from a subprocess rather than a file, which is quite
useful in deployments with large userbases
feedback and ok markus@
Upstream-ID: aa1bdac7b16fc6d2fa3524ef08f04c7258d247f6
Don't send hostkey advertisments
(hostkeys-00@openssh.com) to current versions of Tera Term as they can't
handle them. Newer versions should be OK. Patch from Bryan Drewery and
IWAMOTO Kouichi, ok djm@
UpdateHostKeys fixes:
I accidentally changed the format of the hostkeys@openssh.com messages
last week without changing the extension name, and this has been causing
connection failures for people who are running -current. First reported
by sthen@
s/hostkeys@openssh.com/hostkeys-00@openssh.com/
Change the name of the proof message too, and reorder it a little.
Also, UpdateHostKeys=ask is incompatible with ControlPersist (no TTY
available to read the response) so disable UpdateHostKeys if it is in
ask mode and ControlPersist is active (and document this)
partial backout of:
revision 1.441
date: 2015/01/31 20:30:05; author: djm; state: Exp; lines: +17 -10; commitid
: x8klYPZMJSrVlt3O;
Let sshd load public host keys even when private keys are missing.
Allows sshd to advertise additional keys for future key rotation.
Also log fingerprint of hostkeys loaded; ok markus@
hostkey updates now require access to the private key, so we can't
load public keys only. The improved log messages (fingerprints of keys
loaded) are kept.
Revise hostkeys@openssh.com hostkey learning extension.
The client will not ask the server to prove ownership of the private
halves of any hitherto-unseen hostkeys it offers to the client.
Allow UpdateHostKeys option to take an 'ask' argument to let the
user manually review keys offered.
ok markus@
Let sshd load public host keys even when private keys are
missing. Allows sshd to advertise additional keys for future key rotation.
Also log fingerprint of hostkeys loaded; ok markus@
correctly match ECDSA subtype (== curve) for
offered/recevied host keys. Fixes connection-killing host key mismatches when
a server offers multiple ECDSA keys with different curve type (an extremely
unlikely configuration).
ok markus, "looks mechanical" deraadt@
Host key rotation support.
Add a hostkeys@openssh.com protocol extension (global request) for
a server to inform a client of all its available host key after
authentication has completed. The client may record the keys in
known_hosts, allowing it to upgrade to better host key algorithms
and a server to gracefully rotate its keys.
The client side of this is controlled by a UpdateHostkeys config
option (default on).
ok markus@
update packet.c & isolate, introduce struct ssh a) switch
packet.c to buffer api and isolate per-connection info into struct ssh b)
(de)serialization of the state is moved from monitor to packet.c c) the old
packet.c API is implemented in opacket.[ch] d) compress.c/h is removed and
integrated into packet.c with and ok djm@
Disables and removes dependency on OpenSSL. Many features don't
work and the set of crypto options is greatly restricted. This
will only work on system with native arc4random or /dev/urandom.
Considered highly experimental for now.