[compat.c compat.h sshconnect2.c sshd.c version.h]
OpenSSH 6.5 and 6.6 have a bug that causes ~0.2% of connections
using the curve25519-sha256@libssh.org KEX exchange method to fail
when connecting with something that implements the spec properly.
Disable this KEX method when speaking to one of the affected
versions.
reported by Aris Adamantiadis; ok markus@
repeatedly):
- markus@cvs.openbsd.org 2014/03/25 09:40:03
[myproposal.h]
trimm default proposals.
This commit removes the weaker pre-SHA2 hashes, the broken ciphers
(arcfour), and the broken modes (CBC) from the default configuration
(the patch only changes the default, all the modes are still available
for the config files).
ok djm@, reminded by tedu@ & naddy@ and discussed with many
- deraadt@cvs.openbsd.org 2014/03/26 17:16:26
[myproposal.h]
The current sharing of myproposal[] between both client and server code
makes the previous diff highly unpallatable. We want to go in that
direction for the server, but not for the client. Sigh.
Brought up by naddy.
- markus@cvs.openbsd.org 2014/03/27 23:01:27
[myproposal.h ssh-keyscan.c sshconnect2.c sshd.c]
disable weak proposals in sshd, but keep them in ssh; ok djm@
[auth2-gss.c gss-serv.c ssh-gss.h sshd.c]
bz#2107 - cache OIDs of supported GSSAPI mechanisms before privsep
sandboxing, as running this code in the sandbox can cause violations;
ok markus@
[sshd.c]
use kill(0, ...) instead of killpg(0, ...); on most operating systems
they are equivalent, but SUSv2 describes the latter as having undefined
behaviour; from portable; ok dtucker
(Id sync only; change is already in portable)
[sandbox-null.c sandbox-rlimit.c sandbox-seccomp-filter.c]
[sandbox-systrace.c ssh-sandbox.h sshd.c] Support preauth sandboxing
using the Capsicum API introduced in FreeBSD 10. Patch by Dag-Erling
Smorgrav, updated by Loganaden Velvindron @ AfriNIC; ok dtucker@
[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@
[sshd.c]
delay closure of in/out fds until after "Bad protocol version
identification..." message, as get_remote_ipaddr/get_remote_port
require them open.
[kex.c kex.h myproposal.h ssh-keyscan.c sshconnect2.c sshd.c]
use curve25519 for default key exchange (curve25519-sha256@libssh.org);
initial patch from Aris Adamantiadis; ok djm@
unnecessary arc4random_stir() calls. The only ones left are to ensure
that the PRNG gets a different state after fork() for platforms that
have broken the API.
[ssh-keygen.c sshconnect1.c sshd.c]
All the instances of arc4random_stir() are bogus, since arc4random()
does this itself, inside itself, and has for a very long time.. Actually,
this was probably reducing the entropy available.
ok djm
ID SYNC ONLY for portable; we don't trust other arc4random implementations
to do this right.
[sshd.c]
Stir PRNG after post-accept fork. The child gets a different PRNG state
anyway via rexec and explicit privsep reseeds, but it's good to be sure.
ok markus@
[auth.h kex.h kexdhs.c kexecdhs.c kexgexs.c monitor.c servconf.c]
[servconf.h session.c sshd.c sshd_config.5]
add ssh-agent(1) support to sshd(8); allows encrypted hostkeys,
or hostkeys on smartcards; most of the work by Zev Weiss; bz #1974
ok djm@
[sshd.c]
When running sshd -D, close stderr unless we have explicitly requesting
logging to stderr. From james.hunt at ubuntu.com via bz#1976, djm's patch
so, err, ok dtucker.
[sshd_config.5 servconf.c servconf.h packet.c serverloop.c monitor.c sshd_config
sshd.c] Add RekeyLimit to sshd with the same syntax as the client allowing
rekeying based on traffic volume or time. ok djm@, help & ok jmc@ for the man
page.
[log.c log.h ssh.1 ssh.c sshd.8 sshd.c]
Add -E option to ssh and sshd to append debugging logs to a specified file
instead of stderr or syslog. ok markus@, man page help jmc@
[auth.h auth1.c auth2.c monitor.c servconf.c servconf.h sshd.c]
[sshd_config.5]
Support multiple required authentication via an AuthenticationMethods
option. This option lists one or more comma-separated lists of
authentication method names. Successful completion of all the methods in
any list is required for authentication to complete;
feedback and ok markus@
[auth2-pubkey.c sshd.c sshd_config.5]
Remove default of AuthorizedCommandUser. Administrators are now expected
to explicitly specify a user. feedback and ok markus@
[auth-rsa.c auth.c auth.h auth2-pubkey.c servconf.c servconf.h]
[sshd.c sshd_config sshd_config.5]
new sshd_config option AuthorizedKeysCommand to support fetching
authorized_keys from a command in addition to (or instead of) from
the filesystem. The command is run as the target server user unless
another specified via a new AuthorizedKeysCommandUser option.
patch originally by jchadima AT redhat.com, reworked by me; feedback
and ok markus@
[servconf.c servconf.h sshd.c sshd_config]
Turn on systrace sandboxing of pre-auth sshd by default for new installs
by shipping a config that overrides the current UsePrivilegeSeparation=yes
default. Make it easier to flip the default in the future by adding too.
[sandbox-systrace.c sshd.c]
fix a during the load of the sandbox policies (child can still make
the read-syscall and wait forever for systrace-answers) by replacing
the read/write synchronisation with SIGSTOP/SIGCONT;
report and help hshoexer@; ok djm@, dtucker@
- dtucker@cvs.openbsd.org 2012/05/13 01:42:32
[servconf.h servconf.c sshd.8 sshd.c auth.c sshd_config.5]
Add "Match LocalAddress" and "Match LocalPort" to sshd and adjust tests
to match. Feedback and ok djm@ markus@.
[servconf.c servconf.h sshd.c sshd_config sshd_config.5]
VersionAddendum option to allow server operators to append some arbitrary
text to the SSH-... banner; ok deraadt@ "don't care" markus@
[sshd.c ssh-sandbox.h sandbox.h sandbox-rlimit.c sandbox-systrace.c]
[sandbox-null.c]
rename sandbox.h => ssh-sandbox.h to make things easier for portable
[servconf.c servconf.h sshd.c sshd_config.5 sandbox-rlimit.c]
[sandbox-systrace.c sandbox.h configure.ac Makefile.in]
introduce sandboxing of the pre-auth privsep child using systrace(4).
This introduces a new "UsePrivilegeSeparation=sandbox" option for
sshd_config that applies mandatory restrictions on the syscalls the
privsep child can perform. This prevents a compromised privsep child
from being used to attack other hosts (by opening sockets and proxying)
or probing local kernel attack surface.
The sandbox is implemented using systrace(4) in unsupervised "fast-path"
mode, where a list of permitted syscalls is supplied. Any syscall not
on the list results in SIGKILL being sent to the privsep child. Note
that this requires a kernel with the new SYSTR_POLICY_KILL option.
UsePrivilegeSeparation=sandbox will become the default in the future
so please start testing it now.
feedback dtucker@; ok markus@
[log.c log.h monitor.c monitor.h monitor_wrap.c monitor_wrap.h sshd.c]
make the pre-auth privsep slave log via a socketpair shared with the
monitor rather than /var/empty/dev/log; ok dtucker@ deraadt@ markus@
