changes: fix a use-after-free bug which could be used to potentially
execute arbitrary code with root privileges, provided that the user
has been authenticated using a public key and also that a command
restriction is enforced (the "command" option must be used in
the authorized_keys file)
doesn't conflict with openssh.
Changes since 0.50:
0.52 - Wed 12 November 2008
- Add "netcat-alike" option (-B) to dbclient, allowing Dropbear to
tunnel standard input/output to a TCP port-forwarded remote host.
- Add "proxy command" support to dbclient, to allow using a spawned
process for IO rather than a direct TCP connection. eg
dbclient remotehost
is equivalent to
dbclient -J 'nc remotehost 22' remotehost
(the hostname is still provided purely for looking up saved host keys)
- Combine netcat-alike and proxy support to allow "multihop"
connections, with comma-separated host syntax. Allows running
dbclient user1@host1,user2@host2,user3@host3
to end up at host3 via the other two, using SSH TCP forwarding. It's
a bit like onion-routing. All connections are established from the
local machine. The comma-separated syntax can also be used for
scp/rsync, eg
rsync -a -e dbclient m@gateway,m2@host,martello:/home/matt/ ~/backup/
to bounce through a few hosts.
- Add -I "idle timeout" option (contributed by Farrell Aultman)
- Allow restrictions on authorized_keys logins such as restricting
commands to be run etc. This is a subset of those allowed by OpenSSH,
doesn't yet allow restricting source host.
- Use vfork() for scp on uClinux
- Default to PATH=/usr/bin:/bin for shells.
- Report errors if -R forwarding fails
- Add counter mode cipher support, which avoids some security problems
with the standard CBC mode.
- Support zlib@openssh.com delayed compression for client/server. It
can be required for the Dropbear server with the '-Z' option. This
is useful for security as it avoids exposing the server to attacks
on zlib by unauthenticated remote users, though requires client side
support.
- options.h has been split into options.h (user-changable) and
sysoptions.h (less commonly changed)
- Support "dbclient -s sftp" to specify a subsystem
- Fix a bug in replies to channel requests that could be triggered by
recent versions of PuTTY
0.51 - Thu 27 March 2008
- Make a copy of password fields rather erroneously relying on getwpnam()
to be safe to call multiple times
- If $SSH_ASKPASS_ALWAYS environment variable is set (and $SSH_ASKPASS is
as well) always use that program, ignoring isatty() and $DISPLAY
- Wait until a process exits before the server closes a connection, so
that an exit code can be sent. This fixes problems with exit codes not
being returned, which could cause scp to fail.
changes:
- Add DROPBEAR_PASSWORD environment variable to specify a dbclient password
- Use /dev/urandom by default, since that's what everyone does anyway
- Exit with an exit code of 1 if dropbear can't bind to any ports
- Improve network performance and add a -W <receive_window> argument for
adjusting the tradeoff between network performance and memory consumption
- Fix a problem where reply packets could be sent during key exchange,
in violation of the SSH spec. This could manifest itself with connections
being terminated after 8 hours with new TCP-forward connections being
established
- Add -K <keepalive_time> argument, ensuring that data is transmitted
over the connection at least every N seconds
- dropbearkey will no longer generate DSS keys of sizes other than 1024
bits, as required by the DSS specification. (Other sizes are still
accepted for use to provide backwards compatibility)
changes:
-a security fix which was already in pkgsrc (0.46nb1)
-bugfixes
-zlib compression for dbclient
-Set "low delay" TOS bit
-client keyboard-interactive mode support
-logging improvements
-Added aes-256 cipher and sha1-96 hmac
-allow connections to listening forwarded ports from remote machines
developer is officially maintaining the package.
The rationale for changing this from "tech-pkg" to "pkgsrc-users" is
that it implies that any user can try to maintain the package (by
submitting patches to the mailing list). Since the folks most likely
to care about the package are the folks that want to use it or are
already using it, this would leverage the energy of users who aren't
developers.
http://lists.ucc.gu.uwa.edu.au/pipermail/dropbear/2005q4/000312.html
Noted by waldeck of hk2.uwaterloo.ca via pkgsrc-bugs.
Bump PKGREVISION.
Tested build on NetBSD and Linux. Tested dropbear server on NetBSD.
(This is during a freeze. Other stuff to be done later:
update to latest version. Install man pages. Mention "client" in
COMMENT and DESCR. Use CONF_FILES and sysconfdir. And maybe install the
"scp" tool also.)
changes:
- Makefile no longer appends 'static' to statically linked binaries
- Add optional SSH_ASKPASS support to the client
- Respect HOST_LOOKUP option
- Fix accidentally removed "return;" statement which was removed in 0.44
(causing clients which sent an empty terminal-modes string to fail to
connect - including pssh, ssh.com, danger hiptop). (patches
independently from Paul Fox, David Horwitt and Sven-Ola Tuecke)
- Read "y/n" response for fingerprints from /dev/tty directly so that dbclient
will work with scp.
changes:
-IPv6 support
-client added
-bugfixes
XXX dropbear wants to use /dev/random per default now which makes it
unusable on systems w/o entropy source. I've patched it back to
/dev/urandom. There might be security concerns.
in the process. (More information on tech-pkg.)
Bump PKGREVISION and BUILDLINK_DEPENDS of all packages using libtool and
installing .la files.
Bump PKGREVISION (only) of all packages depending directly on the above
via a buildlink3 include.
- SECURITY: Don't try to free() uninitialised variables in DSS verification
code. Thanks to Arne Bernin for pointing out this bug. This is possibly
exploitable, all users with DSS and pubkey-auth compiled in are advised to
upgrade.
- Clean up agent forwarding socket files correctly, patch from Gerrit Pape.
- Don't go into an infinite loop when portforwarding to servers which don't
send any initial data/banner. Patch from Nikola Vladov
- Fix for network vs. host byte order in logging remote TCP ports, also
from Gerrit Pape.
- Initialise many pointers to NULL, for general safety. Also checked cleanup
code for mp_ints (related to security issues above).
Changes:
0.38 - Sat Oct 11 2003 16:28:13 +0800
o Default hostkey path changed to /etc/dropbear/dropbear_{rsa,dss}_host_key
rather than /etc/dropbear_{rsa,dss}_host_key
o Added SMALL and MULTI text files which have info on compiling for multiple
binaries or small binaries
o Allow for commandline definition of some options.h settings
(without warnings)
o Be more careful handling EINTR
o More fixes for channel closing
o Added multi-binary support
o Improved logging of IPs, now get logged in all cases
o Don't chew cpu when waiting for version identification string, also
make sure that we kick off people if they don't auth within 5 minutes.
o Various small fixes, warnings etc
o sftp support works (relies on OpenSSH sftp binary or similar)
o Added --disable-shadow option (requested by the floppyfw guys)
0.37 - Wed Sept 24 2003 19:42:12 +0800
o Various portability fixes, fixes for Solaris 9, Tru64 5.1, Mac OS X 10.2,
AIX, BSDs
o Updated LibTomMath to 0.27 and LibTomCrypt to 0.90
o Renamed util.{c,h} to dbutil.{c,h} to avoid conflicts with system util.h
o Added some small changes so it'll work with AIX (plus Linux Affinity).
Thanks to Shig for them.
More bugfixes, etc.
The search for a small Secure Shell server to fit on a laptop with 4
megs ram and no hard disk was fruitless, so Matt Johnston decided to
write his own, and Dropbear is the result. It implements various
features of the SSH 2 protocol, including X11 and Authentication Agent
forwarding. Dropbear is Open Source software, distributed under a
MIT-style license.
Features
* A small memory footprint - Dropbear can compile to a 110kB
statically linked binary with uClibc (and only minimal options
selected).
* Implements X11 forwarding, and authentication-agent forwarding
for OpenSSH clients
* Compatible with OpenSSH ~/.ssh/authorized_keys public key
authentication
* Features can easily be disabled when compiling to save space.
* Preliminary TCP forwarding support (-L style only)
