speculation and memory sidechannel attacks like Spectre, Meltdown, Rowhammer
and Rambleed. This change encrypts private keys when they are not in use with
a symmetic key that is derived from a relatively large "prekey" consisting of
random data (currently 16KB).
Attackers must recover the entire prekey with high accuracy before
they can attempt to decrypt the shielded private key, but the current
generation of attacks have bit error rates that, when applied
cumulatively to the entire prekey, make this unlikely.
Implementation-wise, keys are encrypted "shielded" when loaded and then
automatically and transparently unshielded when used for signatures or
when being saved/serialised.
Hopefully we can remove this in a few years time when computer
architecture has become less unsafe.
been in snaps for a bit already; thanks deraadt@
ok dtucker@ deraadt@
OpenBSD-Commit-ID: 19767213c312e46f94b303a512ef8e9218a39bd4
when accepting an unknown host key. This allows you to paste a fingerprint
obtained out of band into the yes/no prompt and have the client do the
comparison for you. ok markus@ djm@
OpenBSD-Commit-ID: 3c47d10b9f43d3d345e044fd9ec09709583a2767
API, started almost exactly six years ago.
This change stops including the old packet_* API by default and makes
each file that requires the old API include it explicitly. We will
commit file-by-file refactoring to remove the old API in consistent
steps.
with & ok markus@
OpenBSD-Commit-ID: 93c98a6b38f6911fd1ae025a1ec57807fb4d4ef4
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
/dev/null. Fixes mosh in proxycommand mode that was broken by the previous
ProxyCommand change that was reported by matthieu@. ok djm@ danj@
OpenBSD-Commit-ID: c6fc9641bc250221a0a81c6beb2e72d603f8add6
it to specify which signature algorithms may be used by CAs when signing
certificates. Useful if you want to ban RSA/SHA1; ok markus@
OpenBSD-Commit-ID: 9159e5e9f67504829bf53ff222057307a6e3230f
original_real_uid and original_effective_uid globals and replace with calls
to plain getuid(). ok djm@
OpenBSD-Commit-ID: 92561c0cd418d34e6841e20ba09160583e27b68c
ssh(1) setuid has been removed, remove supporting code and clean up
references to it in the man pages
We have not shipped ssh(1) the setuid bit since 2002. If ayone
really needs to make connections from a low port number this can
be implemented via a small setuid ProxyCommand.
ok markus@ jmc@ djm@
OpenBSD-Commit-ID: d03364610b7123ae4c6792f5274bd147b6de717e
attempted. Do not link uidwap.c into ssh any more. Neuters
UsePrivilegedPort, which will be marked as deprecated shortly. ok markus@
djm@
OpenBSD-Commit-ID: c4ba5bf9c096f57a6ed15b713a1d7e9e2e373c42
BindInterface required getifaddr and friends so disable if not available
(eg Solaris 10). We should be able to add support for some systems with
a bit more work but this gets the building again.
command-line argument to ssh(1) that directs it to bind its outgoing
connection to the address of the specified network interface.
BindInterface prefers to use addresses that aren't loopback or link-
local, but will fall back to those if no other addresses of the
required family are available on that interface.
Based on patch by Mike Manning in bz#2820, ok dtucker@
OpenBSD-Commit-ID: c5064d285c2851f773dd736a2c342aa384fbf713
ssh_free checks for and handles NULL args, remove NULL
checks from remaining callers. ok djm@
OpenBSD-Commit-ID: bb926825c53724c069df68a93a2597f9192f7e7b
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
try harder to preserve errno during
ssh_connect_direct() to make the final error message possibly accurate;
bz#2814, ok dtucker@
OpenBSD-Commit-ID: 57de882cb47381c319b04499fef845dd0c2b46ca
don't accept junk after "yes" or "no" responses to
hostkey prompts. bz#2803 reported by Maksim Derbasov; ok dtucker@
OpenBSD-Commit-ID: e1b159fb2253be973ce25eb7a7be26e6f967717c
Add monotime_ts and monotime_tv that return monotonic
timespec and timeval respectively. Replace calls to gettimeofday() in packet
timing with monotime_tv so that the callers will work over a clock step.
Should prevent integer overflow during clock steps reported by wangle6 at
huawei.com. "I like" markus@
OpenBSD-Commit-ID: 74d684264814ff806f197948b87aa732cb1b0b8a
Revert commitid: gJtIN6rRTS3CHy9b.
-------------
identify the case where SSHFP records are missing but other DNS RR
types are present and display a more useful error message for this
case; patch by Thordur Bjornsson; bz#2501; ok dtucker@
-------------
This caused unexpected failures when VerifyHostKeyDNS=yes, SSHFP results
are missing but the user already has the key in known_hosts
Spotted by dtucker@
Upstream-ID: 97e31742fddaf72046f6ffef091ec0d823299920
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
Expand ssh_config's StrictModes option with two new
settings:
StrictModes=accept-new will automatically accept hitherto-unseen keys
but will refuse connections for changed or invalid hostkeys.
StrictModes=off is the same as StrictModes=no
Motivation:
StrictModes=no combines two behaviours for host key processing:
automatically learning new hostkeys and continuing to connect to hosts
with invalid/changed hostkeys. The latter behaviour is quite dangerous
since it removes most of the protections the SSH protocol is supposed to
provide.
Quite a few users want to automatically learn hostkeys however, so
this makes that feature available with less danger.
At some point in the future, StrictModes=no will change to be a synonym
for accept-new, with its current behaviour remaining available via
StrictModes=off.
bz#2400, suggested by Michael Samuel; ok markus
Upstream-ID: 0f55502bf75fc93a74fb9853264a8276b9680b64
identify the case where SSHFP records are missing but
other DNS RR types are present and display a more useful error message for
this case; patch by Thordur Bjornsson; bz#2501; ok dtucker@
Upstream-ID: 8f7a5a8344f684823d8317a9708b63e75be2c244
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
use HostKeyAlias if specified instead of hostname for
matching host certificate principal names; bz#2728; ok dtucker@
Upstream-ID: dc2e11c83ae9201bbe74872a0c895ae9725536dd
Add MAXIMUM(), MINIMUM(), and ROUNDUP() to misc.h, then
use those definitions rather than pulling <sys/param.h> and unknown namespace
pollution. ok djm markus dtucker
Upstream-ID: 712cafa816c9f012a61628b66b9fbd5687223fb8
ban ConnectionAttempts=0, it makes no sense and would cause
ssh_connect_direct() to print an uninitialised stack variable; bz#2500
reported by dvw AT phas.ubc.ca
Upstream-ID: 32b5134c608270583a90b93a07b3feb3cbd5f7d5
Add an AddKeysToAgent client option which can be set to
'yes', 'no', 'ask', or 'confirm', and defaults to 'no'. When enabled, a
private key that is used during authentication will be added to ssh-agent if
it is running (with confirmation enabled if set to 'confirm').
Initial version from Joachim Schipper many years ago.
ok markus@
Upstream-ID: a680db2248e8064ec55f8be72d539458c987d5f4
Increase the allowed length of the known host file name
in the log message to be consistent with other cases. Part of bz#1993, ok
deraadt.
Upstream-ID: a9e97567be49f25daf286721450968251ff78397
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@
Add FingerprintHash option to control algorithm used for
key fingerprints. Default changes from MD5 to SHA256 and format from hex to
base64.
Feedback and ok naddy@ markus@
[PROTOCOL auth-options.c auth-passwd.c auth-rh-rsa.c auth-rhosts.c]
[auth-rsa.c auth.c auth1.c auth2-hostbased.c auth2-kbdint.c auth2-none.c]
[auth2-passwd.c auth2-pubkey.c auth2.c canohost.c channels.c channels.h]
[clientloop.c misc.c misc.h monitor.c mux.c packet.c readconf.c]
[readconf.h servconf.c servconf.h serverloop.c session.c ssh-agent.c]
[ssh.c ssh_config.5 sshconnect.c sshconnect1.c sshconnect2.c sshd.c]
[sshd_config.5 sshlogin.c]
Add support for Unix domain socket forwarding. A remote TCP port
may be forwarded to a local Unix domain socket and vice versa or
both ends may be a Unix domain socket. This is a reimplementation
of the streamlocal patches by William Ahern from:
http://www.25thandclement.com/~william/projects/streamlocal.html
OK djm@ markus@
[sshconnect.c]
when rekeying, skip file/DNS lookup if it is the same as the key sent
during initial key exchange. bz#2154 patch from Iain Morgan; ok markus@
[Makefile.in auth-bsdauth.c auth-chall.c auth-options.c auth-rsa.c
[auth2-none.c auth2-pubkey.c authfile.c authfile.h cipher-3des1.c
[cipher-chachapoly.c cipher-chachapoly.h cipher.c cipher.h
[digest-libc.c digest-openssl.c digest.h dns.c entropy.c hmac.h
[hostfile.c key.c key.h krl.c monitor.c packet.c rsa.c rsa.h
[ssh-add.c ssh-agent.c ssh-dss.c ssh-ecdsa.c ssh-ed25519.c
[ssh-keygen.c ssh-pkcs11-client.c ssh-pkcs11-helper.c ssh-pkcs11.c
[ssh-rsa.c sshbuf-misc.c sshbuf.h sshconnect.c sshconnect1.c
[sshconnect2.c sshd.c sshkey.c sshkey.h
[openbsd-compat/openssl-compat.c openbsd-compat/openssl-compat.h]
New key API: refactor key-related functions to be more library-like,
existing API is offered as a set of wrappers.
with and ok markus@
Thanks also to Ben Hawkes, David Tomaschik, Ivan Fratric, Matthew
Dempsky and Ron Bowes for a detailed review a few months ago.
NB. This commit also removes portable OpenSSH support for OpenSSL
<0.9.8e.
[sshconnect.c]
When using VerifyHostKeyDNS with a DNSSEC resolver, down-convert any
certificate keys to plain keys and attempt SSHFP resolution.
Prevents a server from skipping SSHFP lookup and forcing a new-hostkey
dialog by offering only certificate keys.
Reported by mcv21 AT cam.ac.uk
[sshconnect.c]
in ssh_create_socket(), only do the getaddrinfo for BindAddress when
BindAddress is actually specified. Fixes regression in 6.5 for
UsePrivilegedPort=yes; patch from Corinna Vinschen
[sshconnect.c sshd.c]
ban clients/servers that suffer from SSH_BUG_DERIVEKEY, they are ancient,
deranged and might make some attacks on KEX easier; ok markus@
[auth2-hostbased.c auth2-pubkey.c compat.c compat.h ssh-rsa.c]
[sshconnect.c sshconnect2.c sshd.c]
refuse RSA keys from old proprietary clients/servers that use the
obsolete RSA+MD5 signature scheme. it will still be possible to connect
with these clients/servers but only DSA keys will be accepted, and we'll
deprecate them entirely in a future release. ok markus@
[readconf.c readconf.h roaming_client.c ssh.1 ssh.c ssh_config.5]
[sshconnect.c sshconnect.h]
Implement client-side hostname canonicalisation to allow an explicit
search path of domain suffixes to use to convert unqualified host names
to fully-qualified ones for host key matching.
This is particularly useful for host certificates, which would otherwise
need to list unqualified names alongside fully-qualified ones (and this
causes a number of problems).
"looks fine" markus@
[readconf.c readconf.h ssh_config.5 sshconnect.c]
Add a ssh_config ProxyUseFDPass option that supports the use of
ProxyCommands that establish a connection and then pass a connected
file descriptor back to ssh(1). This allows the ProxyCommand to exit
rather than have to shuffle data back and forth and enables ssh to use
getpeername, etc. to obtain address information just like it does with
regular directly-connected sockets. ok markus@
[compat.c sshconnect.c]
Send client banner immediately, rather than waiting for the server to
move first for SSH protocol 2 connections (the default). Patch based on
one in bz#1999 by tls AT panix.com, feedback dtucker@ ok markus@
[readconf.c readconf.h ssh.c ssh_config.5 sshconnect.c sshconnect2.c]
Remove undocumented legacy options UserKnownHostsFile2 and
GlobalKnownHostsFile2 by making UserKnownHostsFile/GlobalKnownHostsFile
accept multiple paths per line and making their defaults include
known_hosts2; ok markus
[auth.c hostfile.c hostfile.h ssh.c ssh_config.5 sshconnect.c]
[sshconnect.h sshconnect2.c]
automatically order the hostkeys requested by the client based on
which hostkeys are already recorded in known_hosts. This avoids
hostkey warnings when connecting to servers with new ECDSA keys
that are preferred by default; with markus@
[PROTOCOL PROTOCOL.agent PROTOCOL.certkeys auth2-jpake.c authfd.c]
[authfile.c buffer.h dns.c kex.c kex.h key.c key.h monitor.c]
[monitor_wrap.c myproposal.h packet.c packet.h pathnames.h readconf.c]
[ssh-add.1 ssh-add.c ssh-agent.1 ssh-agent.c ssh-keygen.1 ssh-keygen.c]
[ssh-keyscan.1 ssh-keyscan.c ssh-keysign.8 ssh.1 ssh.c ssh2.h]
[ssh_config.5 sshconnect.c sshconnect2.c sshd.8 sshd.c sshd_config.5]
[uuencode.c uuencode.h bufec.c kexecdh.c kexecdhc.c kexecdhs.c ssh-ecdsa.c]
Implement Elliptic Curve Cryptography modes for key exchange (ECDH) and
host/user keys (ECDSA) as specified by RFC5656. ECDH and ECDSA offer
better performance than plain DH and DSA at the same equivalent symmetric
key length, as well as much shorter keys.
Only the mandatory sections of RFC5656 are implemented, specifically the
three REQUIRED curves nistp256, nistp384 and nistp521 and only ECDH and
ECDSA. Point compression (optional in RFC5656 is NOT implemented).
Certificate host and user keys using the new ECDSA key types are supported.
Note that this code has not been tested for interoperability and may be
subject to change.
feedback and ok markus@
[PROTOCOL.certkeys auth-options.c auth-options.h auth-rsa.c]
[auth2-pubkey.c authfd.c key.c key.h myproposal.h ssh-add.c]
[ssh-agent.c ssh-dss.c ssh-keygen.1 ssh-keygen.c ssh-rsa.c]
[sshconnect.c sshconnect2.c sshd.c]
revised certificate format ssh-{dss,rsa}-cert-v01@openssh.com with the
following changes:
move the nonce field to the beginning of the certificate where it can
better protect against chosen-prefix attacks on the signature hash
Rename "constraints" field to "critical options"
Add a new non-critical "extensions" field
Add a serial number
The older format is still support for authentication and cert generation
(use "ssh-keygen -t v00 -s ca_key ..." to generate a v00 certificate)
ok markus@
[auth-rh-rsa.c auth-rsa.c auth.c auth.h auth2-hostbased.c auth2-pubkey.c]
[authfile.c authfile.h hostfile.c hostfile.h servconf.c servconf.h]
[ssh-keygen.c ssh.1 sshconnect.c sshd_config.5]
Add a TrustedUserCAKeys option to sshd_config to specify CA keys that
are trusted to authenticate users (in addition than doing it per-user
in authorized_keys).
Add a RevokedKeys option to sshd_config and a @revoked marker to
known_hosts to allow keys to me revoked and banned for user or host
authentication.
feedback and ok markus@
- djm@cvs.openbsd.org 2010/02/26 20:29:54
[PROTOCOL PROTOCOL.agent PROTOCOL.certkeys addrmatch.c auth-options.c]
[auth-options.h auth.h auth2-pubkey.c authfd.c dns.c dns.h hostfile.c]
[hostfile.h kex.h kexdhs.c kexgexs.c key.c key.h match.h monitor.c]
[myproposal.h servconf.c servconf.h ssh-add.c ssh-agent.c ssh-dss.c]
[ssh-keygen.1 ssh-keygen.c ssh-rsa.c ssh.1 ssh.c ssh2.h sshconnect.c]
[sshconnect2.c sshd.8 sshd.c sshd_config.5]
Add support for certificate key types for users and hosts.
OpenSSH certificate key types are not X.509 certificates, but a much
simpler format that encodes a public key, identity information and
some validity constraints and signs it with a CA key. CA keys are
regular SSH keys. This certificate style avoids the attack surface
of X.509 certificates and is very easy to deploy.
Certified host keys allow automatic acceptance of new host keys
when a CA certificate is marked as sh/known_hosts.
see VERIFYING HOST KEYS in ssh(1) for details.
Certified user keys allow authentication of users when the signing
CA key is marked as trusted in authorized_keys. See "AUTHORIZED_KEYS
FILE FORMAT" in sshd(8) for details.
Certificates are minted using ssh-keygen(1), documentation is in
the "CERTIFICATES" section of that manpage.
Documentation on the format of certificates is in the file
PROTOCOL.certkeys
feedback and ok markus@
djm@openbsd.org
dtucker@openbsd.org
markus@openbsd.org
florian@openbsd.org
Darren Tucker
stsp@openbsd.org
dtucker@openbsd.org@openbsd.org
deraadt@openbsd.org
jcs@openbsd.org
Damien Miller
Darren Tucker