[sftp.c]
Deal correctly with failures in remote stat() operation in sftp,
correcting fail-on-error behaviour in batchmode. bz#1541 report and
fix from anedvedicky AT gmail.com; ok markus@
[clientloop.c]
The ~C escape handler does not work correctly for multiplexed sessions -
it opens a commandline on the master session, instead of on the slave
that requested it. Disable it on slave sessions until such time as it
is fixed; bz#1543 report from Adrian Bridgett via Colin Watson
ok markus@
[clientloop.c]
we have to use the recipient's channel number (RFC 4254) for
SSH2_MSG_CHANNEL_SUCCESS/SSH2_MSG_CHANNEL_FAILURE messages,
otherwise we trigger 'Non-public channel' error messages on sshd
systems with clientkeepalive enabled; noticed by sturm; ok djm;
[packet.c]
packet_disconnect() on padding error, too. should reduce the success
probability for the CPNI-957037 Plaintext Recovery Attack to 2^-18
ok djm@
[servconf.c]
USE_AFS not referenced so remove #ifdef. fixes sshd -T not printing
kerberosgetafstoken. ok dtucker@
(Id sync only, we still want the ifdef in portable)
[readconf.c]
because parse_forward() is now used to parse all forward types (DLR),
and it malloc's space for host variables, we don't need to malloc
here. fixes small memory leaks.
previously dynamic forwards were not parsed in parse_forward() and
space was not malloc'd in that case.
ok djm@
[auth.h auth2.c monitor.c monitor.h monitor_wrap.c monitor_wrap.h]
[readconf.c readconf.h servconf.c servconf.h ssh2.h ssh_config.5]
[sshconnect2.c sshd_config.5 jpake.c jpake.h schnorr.c auth2-jpake.c]
[Makefile.in]
Add support for an experimental zero-knowledge password authentication
method using the J-PAKE protocol described in F. Hao, P. Ryan,
"Password Authenticated Key Exchange by Juggling", 16th Workshop on
Security Protocols, Cambridge, April 2008.
This method allows password-based authentication without exposing
the password to the server. Instead, the client and server exchange
cryptographic proofs to demonstrate of knowledge of the password while
revealing nothing useful to an attacker or compromised endpoint.
This is experimental, work-in-progress code and is presently
compiled-time disabled (turn on -DJPAKE in Makefile.inc).
"just commit it. It isn't too intrusive." deraadt@
[ssh.1 ssh.c]
Add -y option to force logging via syslog rather than stderr.
Useful for daemonised ssh connection (ssh -f). Patch originally from
and ok'd by markus@
[sshconnect2.c]
Repair strnvis() buffersize of 4*n+1, with termination gauranteed by the
function.
spotted by des@freebsd, who commited an incorrect fix to the freebsd tree
and (as is fairly typical) did not report the problem to us. But this fix
is correct.
ok djm
[sshd.8]
do not give an example of how to chmod files: we can presume the user
knows that. removes an ambiguity in the permission of authorized_keys;
ok deraadt
[compat.c compat.h nchan.c ssh.c]
only send eow and no-more-sessions requests to openssh 5 and newer;
fixes interop problems with broken ssh v2 implementations; ok djm@
[servconf.c]
do not try to print options that have been compile-time disabled
in config test mode (sshd -T); report from nix-corp AT esperi.org.uk
ok dtucker@
[auth2-hostbased.c]
strip trailing '.' from hostname when HostbasedUsesNameFromPacketOnly=yes
report and patch from res AT qoxp.net (bz#1200); ok markus@
[sftp.c]
increase number of piplelined requests so they properly fill the
(recently increased) channel window. prompted by rapier AT psc.edu;
ok markus@
[ssh-keygen.c]
Change "ssh-keygen -F [host] -l" to not display random art unless
-v is also specified, making it consistent with the manual and other
uses of -l.
ok grunk@
[auth1.c auth2.c]
Make protocol 1 MaxAuthTries logic match protocol 2's.
Do not treat the first protocol 2 authentication attempt as
a failure IFF it is for method "none".
Makes MaxAuthTries' user-visible behaviour identical for
protocol 1 vs 2.
ok dtucker@
[packet.c scp.c serverloop.c sftp-client.c ssh-agent.c ssh-keyscan.c]
[sshd.c] Explicitly handle EWOULDBLOCK wherever we handle EAGAIN, on
some platforms (HP nonstop) it is a distinct errno;
bz#1467 reported by sconeu AT yahoo.com; ok dtucker@
[ssh.1 ssh.c]
When forking after authentication ("ssh -f") with ExitOnForwardFailure
enabled, delay the fork until after replies for any -R forwards have
been seen. Allows for robust detection of -R forward failure when
using -f (similar to bz#92); ok dtucker@
[auth2-none.c auth2.c]
Make protocol 2 MaxAuthTries behaviour a little more sensible:
Check whether client has exceeded MaxAuthTries before running
an authentication method and skip it if they have, previously it
would always allow one try (for "none" auth).
Preincrement failure count before post-auth test - previously this
checked and postincremented, also to allow one "none" try.
Together, these two changes always count the "none" auth method
which could be skipped by a malicious client (e.g. an SSH worm)
to get an extra attempt at a real auth method. They also make
MaxAuthTries=0 a useful way to block users entirely (esp. in a
sshd_config Match block).
Also, move sending of any preauth banner from "none" auth method
to the first call to input_userauth_request(), so worms that skip
the "none" method get to see it too.
[auth-rsa.c auth.c auth2-pubkey.c auth.h]
Merge duplicate host key file checks, based in part on a patch from Rob
Holland via bz #1348 . Also checks for non-regular files during protocol
1 RSA auth. ok djm@
[sshd_config sshd_config.5 sshd.8 servconf.c]
increase default size of ssh protocol 1 ephemeral key from 768 to 1024
bits; prodded by & ok dtucker@ ok deraadt@
[regress/Makefile regress/test-exec.sh regress/conch-ciphers.sh]
very basic regress test against Twisted Conch in "make interop"
target (conch is available in ports/devel/py-twisted/conch);
ok markus@
[readconf.c readconf.h ssh.1 ssh_config.5 sshconnect.c]
Move SSH Fingerprint Visualization away from sharing the config option
CheckHostIP to an own config option named VisualHostKey.
While there, fix the behaviour that ssh would draw a random art picture
on every newly seen host even when the option was not enabled.
prodded by deraadt@, discussions,
help and ok markus@ djm@ dtucker@
[dh.c dh.h moduli.c]
when loading moduli from /etc/moduli in sshd(8), check that they
are of the expected "safe prime" structure and have had
appropriate primality tests performed;
feedback and ok dtucker@
[sftp-client.c sftp-server.c]
allow the sftp chmod(2)-equivalent operation to set set[ug]id/sticky
bits. Note that this only affects explicit setting of modes (e.g. via
sftp(1)'s chmod command) and not file transfers. (bz#1310)
ok deraadt@ at c2k8
- martynas@cvs.openbsd.org 2008/06/21 07:46:46
[sftp.c]
use optopt to get invalid flag, instead of return value of getopt,
which is always '?'; ok djm@
[channels.c channels.h session.c]
don't call isatty() on a pty master, instead pass a flag down to
channel_set_fds() indicating that te fds refer to a tty. Fixes a
hang on exit on Solaris (bz#1463) in portable but is actually
a generic bug; ok dtucker deraadt markus
[ssh.1]
Explain the use of SSH fpr visualization using random art, and cite the
original scientific paper inspiring that technique.
Much help with English and nroff by jmc@, thanks.
[monitor.c]
Clear key options in the monitor on failed authentication, prevents
applying additional restrictions to non-pubkey authentications in
the case where pubkey fails but another method subsequently succeeds.
bz #1472, found by Colin Watson, ok markus@ djm
[auth2-pubkey.c auth-rhosts.c]
refuse to read ~/.shosts or ~/.ssh/authorized_keys that are not
regular files; report from Solar Designer via Colin Watson in bz#1471
ok dtucker@ deraadt@
[mux.c]
fall back to creating a new TCP connection on most multiplexing errors
(socket connect fail, invalid version, refused permittion, corrupted
messages, etc.); bz #1329 ok dtucker@
[sshd.c sshconnect.c packet.h misc.c misc.h packet.c]
Make keepalive timeouts apply while waiting for a packet, particularly
during key renegotiation (bz #1363). With djm and Matt Day, ok djm@
[clientloop.h channels.h clientloop.c channels.c mux.c]
The multiplexing escape char handler commit last night introduced a
small memory leak per session; plug it.
[clientloop.h ssh.c clientloop.c]
maintain an ordered queue of outstanding global requests that we
expect replies to, similar to the per-channel confirmation queue.
Use this queue to verify success or failure for remote forward
establishment in a race free way.
ok dtucker@
[clientloop.h mux.c channels.c clientloop.c channels.h]
Enable ~ escapes for multiplex slave sessions; give each channel
its own escape state and hook the escape filters up to muxed
channels. bz #1331
Mux slaves do not currently support the ~^Z and ~& escapes.
NB. this change cranks the mux protocol version, so a new ssh
mux client will not be able to connect to a running old ssh
mux master.
ok dtucker@
[key.c]
#define statements that are not atoms need braces around them, else they
will cause trouble in some cases.
Also do a computation of -1 once, and not in a loop several times.
spotted by otto@
[ssh-keygen.c ssh-keygen.1]
ssh-keygen would write fingerprints to STDOUT, and random art to STDERR,
that is not how it was envisioned.
Also correct manpage saying that -v is needed along with -l for it to work.
spotted by naddy@
[ssh_config.5 key.h readconf.c readconf.h ssh-keygen.1 ssh-keygen.c key.c
sshconnect.c]
Introduce SSH Fingerprint ASCII Visualization, a technique inspired by the
graphical hash visualization schemes known as "random art", and by
Dan Kaminsky's musings on the subject during a BlackOp talk at the
23C3 in Berlin.
Scientific publication (original paper):
"Hash Visualization: a New Technique to improve Real-World Security",
Perrig A. and Song D., 1999, International Workshop on Cryptographic
Techniques and E-Commerce (CrypTEC '99)
http://sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
The algorithm used here is a worm crawling over a discrete plane,
leaving a trace (augmenting the field) everywhere it goes.
Movement is taken from dgst_raw 2bit-wise. Bumping into walls
makes the respective movement vector be ignored for this turn,
thus switching to the other color of the chessboard.
Graphs are not unambiguous for now, because circles in graphs can be
walked in either direction.
discussions with several people,
help, corrections and ok markus@ djm@
[auth-options.c match.c servconf.c addrmatch.c sshd.8]
support CIDR address matching in .ssh/authorized_keys from="..." stanzas
ok and extensive testing dtucker@
[PROTOCOL ssh.c serverloop.c]
Add a no-more-sessions@openssh.com global request extension that the
client sends when it knows that it will never request another session
(i.e. when session multiplexing is disabled). This allows a server to
disallow further session requests and terminate the session.
Why would a non-multiplexing client ever issue additional session
requests? It could have been attacked with something like SSH'jack:
http://www.storm.net.nz/projects/7
feedback & ok markus
[sshd.c channels.h channels.c log.c servconf.c log.h servconf.h sshd.8]
Add extended test mode (-T) and connection parameters for test mode (-C).
-T causes sshd to write its effective configuration to stdout and exit.
-C causes any relevant Match rules to be applied before output. The
combination allows tesing of the parser and config files. ok deraadt djm
- djm@cvs.openbsd.org 2008/06/10 03:57:27
[servconf.c match.h sshd_config.5]
support CIDR address matching in sshd_config "Match address" blocks, with
full support for negation and fall-back to classic wildcard matching.
For example:
Match address 192.0.2.0/24,3ffe:ffff::/32,!10.*
PasswordAuthentication yes
addrmatch.c code mostly lifted from flowd's addr.c
feedback and ok dtucker@
[sftp.c sftp-client.c sftp-client.h]
Have the sftp client store the statvfs replies in wire format,
which prevents problems when the server's native sizes exceed the
client's.
Also extends the sizes of the remaining 32bit wire format to 64bit,
they're specified as unsigned long in the standard.
openbsd-compat/Makefile.in openbsd-compat/openbsd-compat.h
openbsd-compat/bsd-statvfs.{c,h}] Add a null implementation of statvfs and
fstatvfs and remove #defines around statvfs code. ok djm@
[clientloop.c]
unbreak tree by committing this bit that I missed from:
Fix sending tty modes when stdin is not a tty (bz#1199). Previously
we would send the modes corresponding to a zeroed struct termios,
whereas we should have been sending an empty list of modes.
Based on patch from daniel.ritz AT alcatel.ch; ok dtucker@ markus@
[ssh-keygen.c]
support -l (print fingerprint) in combination with -F (find host) to
search for a host in ~/.ssh/known_hosts and display its fingerprint;
ok markus@
[sshtty.c ttymodes.c sshpty.h]
Fix sending tty modes when stdin is not a tty (bz#1199). Previously
we would send the modes corresponding to a zeroed struct termios,
whereas we should have been sending an empty list of modes.
Based on patch from daniel.ritz AT alcatel.ch; ok dtucker@ markus@
[openbsd-compat/fmt_scaled.c openbsd-compat/openbsd-compat.h]
Fix compilation on Linux, including pulling in fmt_scaled(3)
implementation from OpenBSD's libutil.
[PROTOCOL]
document our protocol extensions and deviations; ok markus@
- djm@cvs.openbsd.org 2008/05/17 01:31:56
[PROTOCOL]
grammar and correctness fixes from stevesk@
[channels.h clientloop.c nchan.c serverloop.c]
unbreak
ssh -2 localhost od /bin/ls | true
ignoring SIGPIPE by adding a new channel message (EOW) that signals
the peer that we're not interested in any data it might send.
fixes bz #85; discussion, debugging and ok djm@
[channels.c]
error-fd race: don't enable the error fd in the select bitmask
for channels with both in- and output closed, since the channel
will go away before we call select();
report, lots of debugging help and ok djm@
[session.c]
re-add the USE_PIPES code and enable it.
without pipes shutdown-read from the sshd does not trigger
a SIGPIPE when the forked program does a write.
ok djm@
(Id sync only, USE_PIPES never left portable OpenSSH)
[clientloop.c clientloop.h ssh.c mux.c]
tidy up session multiplexing code, moving it into its own file and
making the function names more consistent - making ssh.c and
clientloop.c a fair bit more readable.
ok markus@
[channels.c channels.h clientloop.c serverloop.c]
Try additional addresses when connecting to a port forward destination
whose DNS name resolves to more than one address. The previous behaviour
was to try the first address and give up.
Reported by stig AT venaas.com in bz#343
great feedback and ok markus@
[clientloop.c clientloop.h ssh.c]
Use new channel status confirmation callback system to properly deal
with "important" channel requests that fail, in particular command exec,
shell and subsystem requests. Previously we would optimistically assume
that the requests would always succeed, which could cause hangs if they
did not (e.g. when the server runs out of fds) or were unimplemented by
the server (bz #1384)
Also, properly report failing multiplex channel requests via the mux
client stderr (subject to LogLevel in the mux master) - better than
silently failing.
most bits ok markus@ (as part of a larger diff)
[monitor.c monitor_wrap.c session.h servconf.c servconf.h session.c]
[sshd_config sshd_config.5]
Make the maximum number of sessions run-time controllable via
a sshd_config MaxSessions knob. This is useful for disabling
login/shell/subsystem access while leaving port-forwarding working
(MaxSessions 0), disabling connection multiplexing (MaxSessions 1) or
simply increasing the number of allows multiplexed sessions.
Because some bozos are sure to configure MaxSessions in excess of the
number of available file descriptors in sshd (which, at peak, might be
as many as 9*MaxSessions), audit sshd to ensure that it doesn't leak fds
on error paths, and make it fail gracefully on out-of-fd conditions -
sending channel errors instead of than exiting with fatal().
bz#1090; MaxSessions config bits and manpage from junyer AT gmail.com
ok markus@
[auth-options.c auth1.c channels.c channels.h clientloop.c gss-serv.c]
[monitor.c monitor_wrap.c nchan.c servconf.c serverloop.c session.c]
[ssh.c sshd.c]
Implement a channel success/failure status confirmation callback
mechanism. Each channel maintains a queue of callbacks, which will
be drained in order (RFC4253 guarantees confirm messages are not
reordered within an channel).
Also includes a abandonment callback to clean up if a channel is
closed without sending confirmation messages. This probably
shouldn't happen in compliant implementations, but it could be
abused to leak memory.
ok markus@ (as part of a larger diff)
[bufaux.c buffer.h channels.c packet.c packet.h]
avoid extra malloc/copy/free when receiving data over the net;
~10% speedup for localhost-scp; ok djm@
[servconf.c servconf.h session.c sshd_config.5]
Enable the AllowAgentForwarding option in sshd_config (global and match
context), to specify if agents should be permitted on the server.
As the man page states:
``Note that disabling Agent forwarding does not improve security
unless users are also denied shell access, as they can always install
their own forwarders.''
ok djm@, ok and a mild frown markus@
[sftp-client.c sftp-client.h sftp-server.c sftp.1 sftp.c sftp.h]
introduce sftp extension methods statvfs@openssh.com and
fstatvfs@openssh.com that implement statvfs(2)-like operations,
based on a patch from miklos AT szeredi.hu (bz#1399)
also add a "df" command to the sftp client that uses the
statvfs@openssh.com to produce a df(1)-like display of filesystem
space and inode utilisation
ok markus@
- djm@cvs.openbsd.org 2008/04/13 00:22:17
[dh.c sshd.c]
Use arc4random_buf() when requesting more than a single word of output
Use arc4random_uniform() when the desired random number upper bound
is not a power of two
ok deraadt@ millert@
- djm@cvs.openbsd.org 2008/04/04 05:14:38
[sshd_config.5]
ChrootDirectory is supported in Match blocks (in fact, it is most useful
there). Spotted by Minstrel AT minstrel.org.uk
Damien Miller
Darren Tucker
Tim Rice