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2008-07-22* New upstream release (closes: #474301). Important changes not previouslyColin Watson
backported to 4.7p1: - 4.9/4.9p1 (http://www.openssh.com/txt/release-4.9): + Added chroot(2) support for sshd(8), controlled by a new option "ChrootDirectory" (closes: #139047, LP: #24777). + Linked sftp-server(8) into sshd(8). The internal sftp server is used when the command "internal-sftp" is specified in a Subsystem or ForceCommand declaration. When used with ChrootDirectory, the internal sftp server requires no special configuration of files inside the chroot environment. + Added a protocol extension method "posix-rename@openssh.com" for sftp-server(8) to perform POSIX atomic rename() operations; sftp(1) prefers this if available (closes: #308561). + Removed the fixed limit of 100 file handles in sftp-server(8). + ssh(8) will now skip generation of SSH protocol 1 ephemeral server keys when in inetd mode and protocol 2 connections are negotiated. This speeds up protocol 2 connections to inetd-mode servers that also allow Protocol 1. + Accept the PermitRootLogin directive in a sshd_config(5) Match block. Allows for, e.g. permitting root only from the local network. + Reworked sftp(1) argument splitting and escaping to be more internally consistent (i.e. between sftp commands) and more consistent with sh(1). Please note that this will change the interpretation of some quoted strings, especially those with embedded backslash escape sequences. + Support "Banner=none" in sshd_config(5) to disable sending of a pre-login banner (e.g. in a Match block). + ssh(1) ProxyCommands are now executed with $SHELL rather than /bin/sh. + ssh(1)'s ConnectTimeout option is now applied to both the TCP connection and the SSH banner exchange (previously it just covered the TCP connection). This allows callers of ssh(1) to better detect and deal with stuck servers that accept a TCP connection but don't progress the protocol, and also makes ConnectTimeout useful for connections via a ProxyCommand. + scp(1) incorrectly reported "stalled" on slow copies (closes: #140828). + scp(1) date underflow for timestamps before epoch. + ssh(1) used the obsolete SIG DNS RRtype for host keys in DNS, instead of the current standard RRSIG. + Correctly drain ACKs when a sftp(1) upload write fails midway, avoids a fatal() exit from what should be a recoverable condition. + Fixed ssh-keygen(1) selective host key hashing (i.e. "ssh-keygen -HF hostname") to not include any IP address in the data to be hashed. + Make ssh(1) skip listening on the IPv6 wildcard address when a binding address of 0.0.0.0 is used against an old SSH server that does not support the RFC4254 syntax for wildcard bind addresses. + Enable IPV6_V6ONLY socket option on sshd(8) listen socket, as is already done for X11/TCP forwarding sockets (closes: #439661). + Fix FD leak that could hang a ssh(1) connection multiplexing master. + Make ssh(1) -q option documentation consistent with reality. + Fixed sshd(8) PAM support not calling pam_session_close(), or failing to call it with root privileges (closes: #372680). + Fix activation of OpenSSL engine support when requested in configure (LP: #119295). - 5.1/5.1p1 (http://www.openssh.com/txt/release-5.1): + Introduce experimental SSH Fingerprint ASCII Visualisation to ssh(1) and ssh-keygen(1). Visual fingerprint display is controlled by a new ssh_config(5) option "VisualHostKey". The intent is to render SSH host keys in a visual form that is amenable to easy recall and rejection of changed host keys. + sshd_config(5) now supports CIDR address/masklen matching in "Match address" blocks, with a fallback to classic wildcard matching. + sshd(8) now supports CIDR matching in ~/.ssh/authorized_keys from="..." restrictions, also with a fallback to classic wildcard matching. + Added an extended test mode (-T) to sshd(8) to request that it write its effective configuration to stdout and exit. Extended test mode also supports the specification of connection parameters (username, source address and hostname) to test the application of sshd_config(5) Match rules. + ssh(1) now prints the number of bytes transferred and the overall connection throughput for SSH protocol 2 sessions when in verbose mode (previously these statistics were displayed for protocol 1 connections only). + sftp-server(8) now supports extension methods statvfs@openssh.com and fstatvfs@openssh.com that implement statvfs(2)-like operations. + sftp(1) now has 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 (requires statvfs@openssh.com support on the server). + Added a MaxSessions option to sshd_config(5) to allow control of the number of multiplexed sessions supported over a single TCP connection. This allows increasing the number of allowed sessions above the previous default of 10, disabling connection multiplexing (MaxSessions=1) or disallowing login/shell/subsystem sessions entirely (MaxSessions=0). + Added a no-more-sessions@openssh.com global request extension that is sent from ssh(1) to sshd(8) when the client 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 in cases where the client has been hijacked. + ssh-keygen(1) now supports the use of the -l option in combination with -F to search for a host in ~/.ssh/known_hosts and display its fingerprint. + ssh-keyscan(1) now defaults to "rsa" (protocol 2) keys, instead of "rsa1". + Added an AllowAgentForwarding option to sshd_config(8) to control whether authentication agent forwarding is permitted. Note that this is a loose control, as a client may install their own unofficial forwarder. + ssh(1) and sshd(8): avoid unnecessary malloc/copy/free when receiving network data, resulting in a ~10% speedup. + ssh(1) and sshd(8) will now 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 only first address and give up if that failed. + ssh(1) and sshd(8) now support signalling that channels are half-closed for writing, through a channel protocol extension notification "eow@openssh.com". This allows propagation of closed file descriptors, so that commands such as "ssh -2 localhost od /bin/ls | true" do not send unnecessary data over the wire. + sshd(8): increased the default size of ssh protocol 1 ephemeral keys from 768 to 1024 bits. + When ssh(1) has been requested to fork 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. + "Match group" blocks in sshd_config(5) now support negation of groups. E.g. "Match group staff,!guests". + sftp(1) and sftp-server(8) now allow chmod-like operations to set set[ug]id/sticky bits. + The MaxAuthTries option is now permitted in sshd_config(5) match blocks. + Multiplexed ssh(1) sessions now support a subset of the ~ escapes that are available to a primary connection. + ssh(1) connection multiplexing will now fall back to creating a new connection in most error cases (closes: #352830). + Make ssh(1) deal more gracefully with channel requests that fail. Previously it would optimistically assume that requests would always succeed, which could cause hangs if they did not (e.g. when the server runs out of file descriptors). + ssh(1) now reports multiplexing errors via the multiplex slave's stderr where possible (subject to LogLevel in the mux master). + Prevent sshd(8) from erroneously applying public key restrictions leaned from ~/.ssh/authorized_keys to other authentication methods when public key authentication subsequently fails (LP: #161047). + Fixed an UMAC alignment problem that manifested on Itanium platforms.
2008-06-30 - grunk@cvs.openbsd.org 2008/06/26 11:46:31Damien Miller
[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@
2008-06-13 - jmc@cvs.openbsd.org 2008/06/12 19:10:09Darren Tucker
[ssh_config.5 ssh-keygen.1] tweak the ascii art text; ok grunk
2008-06-13 - dtucker@cvs.openbsd.org 2008/06/12 16:35:31Darren Tucker
[ssh_config.5 ssh.c] keyword expansion for localcommand. ok djm@
2008-06-13 - grunk@cvs.openbsd.org 2008/06/11 23:03:56Darren Tucker
[ssh_config.5] CheckHostIP set to ``fingerprint'' will display both hex and random art spotted by naddy@
2008-06-13 - grunk@cvs.openbsd.org 2008/06/11 21:01:35Darren Tucker
[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@
2008-06-11 - dtucker@cvs.openbsd.org 2008/06/10 18:21:24Darren Tucker
[ssh_config.5] clarify that Host patterns are space-separated. ok deraadt
2008-06-02Check compromised key blacklist in ssh or ssh-add, as well as in theColin Watson
server (LP: #232391). To override the blacklist check in ssh temporarily, use 'ssh -o UseBlacklistedKeys=yes'; there is no override for the blacklist check in ssh-add.
2007-12-24* Document the non-default options we set as standard in ssh_config(5) andColin Watson
sshd_config(5) (closes: #327886, #345628).
2007-12-24* New upstream release (closes: #453367).Colin Watson
- CVE-2007-4752: Prevent ssh(1) from using a trusted X11 cookie if creation of an untrusted cookie fails; found and fixed by Jan Pechanec (closes: #444738). - sshd(8) in new installations defaults to SSH Protocol 2 only. Existing installations are unchanged. - The SSH channel window size has been increased, and both ssh(1) sshd(8) now send window updates more aggressively. These improves performance on high-BDP (Bandwidth Delay Product) networks. - ssh(1) and sshd(8) now preserve MAC contexts between packets, which saves 2 hash calls per packet and results in 12-16% speedup for arcfour256/hmac-md5. - A new MAC algorithm has been added, UMAC-64 (RFC4418) as "umac-64@openssh.com". UMAC-64 has been measured to be approximately 20% faster than HMAC-MD5. - Failure to establish a ssh(1) TunnelForward is now treated as a fatal error when the ExitOnForwardFailure option is set. - ssh(1) returns a sensible exit status if the control master goes away without passing the full exit status. - When using a ProxyCommand in ssh(1), set the outgoing hostname with gethostname(2), allowing hostbased authentication to work. - Make scp(1) skip FIFOs rather than hanging (closes: #246774). - Encode non-printing characters in scp(1) filenames. These could cause copies to be aborted with a "protocol error". - Handle SIGINT in sshd(8) privilege separation child process to ensure that wtmp and lastlog records are correctly updated. - Report GSSAPI mechanism in errors, for libraries that support multiple mechanisms. - Improve documentation for ssh-add(1)'s -d option. - Rearrange and tidy GSSAPI code, removing server-only code being linked into the client. - Delay execution of ssh(1)'s LocalCommand until after all forwardings have been established. - In scp(1), do not truncate non-regular files. - Improve exit message from ControlMaster clients. - Prevent sftp-server(8) from reading until it runs out of buffer space, whereupon it would exit with a fatal error (closes: #365541). - pam_end() was not being called if authentication failed (closes: #405041). - Manual page datestamps updated (closes: #433181).
2007-12-02 - jmc@cvs.openbsd.org 2007/10/29 07:48:19Darren Tucker
[ssh_config.5] clean up after previous macro removal;
2007-12-02 - dtucker@cvs.openbsd.org 2007/10/29 06:51:59Darren Tucker
[ssh_config.5] ProxyCommand and LocalCommand use the user's shell, not /bin/sh; ok djm@
2007-10-26 - djm@cvs.openbsd.org 2007/09/21 03:05:23Damien Miller
[ssh_config.5] document KbdInteractiveAuthentication in ssh_config.5; patch from dkg AT fifthhorseman.net
2007-08-15 - stevesk@cvs.openbsd.org 2007/08/15 12:13:41Darren Tucker
[ssh_config.5] tun device forwarding now honours ExitOnForwardFailure; ok markus@
2007-06-29* Document that HashKnownHosts may break tab-completion (closes: #430154).Colin Watson
2007-06-13* Document the SILENT loglevel in sftp-server(8), ssh_config(5), andColin Watson
sshd_config(5).
2007-06-12* New upstream release (closes: #395507, #397961, #420035). ImportantColin Watson
changes not previously backported to 4.3p2: - 4.4/4.4p1 (http://www.openssh.org/txt/release-4.4): + On portable OpenSSH, fix a GSSAPI authentication abort that could be used to determine the validity of usernames on some platforms. + Implemented conditional configuration in sshd_config(5) using the "Match" directive. This allows some configuration options to be selectively overridden if specific criteria (based on user, group, hostname and/or address) are met. So far a useful subset of post-authentication options are supported and more are expected to be added in future releases. + Add support for Diffie-Hellman group exchange key agreement with a final hash of SHA256. + Added a "ForceCommand" directive to sshd_config(5). Similar to the command="..." option accepted in ~/.ssh/authorized_keys, this forces the execution of the specified command regardless of what the user requested. This is very useful in conjunction with the new "Match" option. + Add a "PermitOpen" directive to sshd_config(5). This mirrors the permitopen="..." authorized_keys option, allowing fine-grained control over the port-forwardings that a user is allowed to establish. + Add optional logging of transactions to sftp-server(8). + ssh(1) will now record port numbers for hosts stored in ~/.ssh/known_hosts when a non-standard port has been requested (closes: #50612). + Add an "ExitOnForwardFailure" option to cause ssh(1) to exit (with a non-zero exit code) when requested port forwardings could not be established. + Extend sshd_config(5) "SubSystem" declarations to allow the specification of command-line arguments. + Replacement of all integer overflow susceptible invocations of malloc(3) and realloc(3) with overflow-checking equivalents. + Many manpage fixes and improvements. + Add optional support for OpenSSL hardware accelerators (engines), enabled using the --with-ssl-engine configure option. + Tokens in configuration files may be double-quoted in order to contain spaces (closes: #319639). + Move a debug() call out of a SIGCHLD handler, fixing a hang when the session exits very quickly (closes: #307890). + Fix some incorrect buffer allocation calculations (closes: #410599). + ssh-add doesn't ask for a passphrase if key file permissions are too liberal (closes: #103677). + Likewise, ssh doesn't ask either (closes: #99675). - 4.6/4.6p1 (http://www.openssh.org/txt/release-4.6): + sshd now allows the enabling and disabling of authentication methods on a per user, group, host and network basis via the Match directive in sshd_config. + Fixed an inconsistent check for a terminal when displaying scp progress meter (closes: #257524). + Fix "hang on exit" when background processes are running at the time of exit on a ttyful/login session (closes: #88337). * Update to current GSSAPI patch from http://www.sxw.org.uk/computing/patches/openssh-4.6p1-gsskex-20070312.patch; install ChangeLog.gssapi.
2007-06-11 - jmc@cvs.openbsd.org 2007/06/08 07:43:46Damien Miller
[ssh_config.5] put the MAC list into a display, like we do for ciphers, since groff has trouble handling wide lines;
2007-06-11 - pvalchev@cvs.openbsd.org 2007/06/07 19:37:34Damien Miller
[kex.h mac.c mac.h monitor_wrap.c myproposal.h packet.c ssh.1] [ssh_config.5 sshd.8 sshd_config.5] Add a new MAC algorithm for data integrity, UMAC-64 (not default yet, must specify umac-64@openssh.com). Provides about 20% end-to-end speedup compared to hmac-md5. Represents a different approach to message authentication to that of HMAC that may be beneficial if HMAC based on one of its underlying hash algorithms is found to be vulnerable to a new attack. http://www.ietf.org/rfc/rfc4418.txt in conjunction with and OK djm@
2007-06-05 - jmc@cvs.openbsd.org 2007/05/31 19:20:16Darren Tucker
[scp.1 ssh_config.5 sftp-server.8 ssh-agent.1 sshd_config.5 sftp.1 ssh-keygen.1 ssh-keyscan.1 ssh-add.1 sshd.8 ssh.1 ssh-keysign.8] convert to new .Dd format; (We will need to teach mdoc2man.awk to understand this too.)
2007-02-19 - jmc@cvs.openbsd.org 2007/01/10 13:23:22Darren Tucker
[ssh_config.5] do not use a list for SYNOPSIS; this is actually part of a larger report sent by eric s. raymond and forwarded by brad, but i only read half of it. spotted by brad.
2006-08-05 - jmc@cvs.openbsd.org 2006/07/27 08:00:50Damien Miller
[ssh_config.5] avoid confusing wording in HashKnownHosts: originally spotted by alan amesbury; ok deraadt
2006-07-12 - markus@cvs.openbsd.org 2006/07/11 18:50:48Darren Tucker
[clientloop.c ssh.1 ssh.c channels.c ssh_config.5 readconf.h session.c channels.h readconf.c] add ExitOnForwardFailure: terminate the connection if ssh(1) cannot set up all requested dynamic, local, and remote port forwardings. ok djm, dtucker, stevesk, jmc
2006-07-10 - stevesk@cvs.openbsd.org 2006/07/02 17:12:58Damien Miller
[ssh.1 ssh.c ssh_config.5 sshd_config.5] more details and clarity for tun(4) device forwarding; ok and help jmc@
2006-06-13 - jmc@cvs.openbsd.org 2006/05/29 16:10:03Damien Miller
[ssh_config.5] oops - previous was too long; split the list of auths up
2006-06-13 - dtucker@cvs.openbsd.org 2006/05/29 12:54:08Damien Miller
[ssh_config.5] Add gssapi-with-mic to PreferredAuthentications default list; ok jmc
2006-05-12* Update to current GSSAPI patch fromColin Watson
http://www.sxw.org.uk/computing/patches/openssh-4.3p2-gsskex-20060223.patch (closes: #352042).
2006-05-12Merge 4.3p2 to the trunk.Colin Watson
2006-03-31 - djm@cvs.openbsd.org 2006/03/31 09:13:56Damien Miller
[ssh_config.5] remote user escape is %r not %h; spotted by jmc@
2006-03-31 - jmc@cvs.openbsd.org 2006/03/31 09:09:30Damien Miller
[ssh_config.5] kill trailing whitespace;
2006-03-31 - djm@cvs.openbsd.org 2006/03/30 10:41:25Damien Miller
[ssh.c ssh_config.5] add percent escape chars to the IdentityFile option, bz #1159 based on a patch by imaging AT math.ualberta.ca; feedback and ok dtucker@
2006-03-15 - markus@cvs.openbsd.org 2006/03/14 16:32:48Damien Miller
[ssh_config.5 sshd_config.5] *AliveCountMax applies to protcol v2 only; ok dtucker, djm
2006-03-15 - dtucker@cvs.openbsd.org 2006/03/13 10:14:29Damien Miller
[misc.c ssh_config.5 sshd_config.5] Allow config directives to contain whitespace by surrounding them by double quotes. mindrot #482, man page help from jmc@, ok djm@
2006-03-15 - jmc@cvs.openbsd.org 2006/02/26 18:03:10Damien Miller
[ssh_config.5] comma;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/26 17:17:18Damien Miller
[ssh_config.5] move PATTERNS to the end of the main body; requested by dtucker
2006-03-15 - jmc@cvs.openbsd.org 2006/02/25 12:26:17Damien Miller
[ssh_config.5] document the possible values for KbdInteractiveDevices;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/24 23:20:07Damien Miller
[ssh_config.5] some grammar/wording fixes;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/24 20:31:31Damien Miller
[ssh.1 ssh_config.5 sshd.8 sshd_config.5] more consistency fixes;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/24 20:22:16Damien Miller
[ssh-keysign.8 ssh_config.5 sshd_config.5] some consistency fixes;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/24 10:37:07Damien Miller
[ssh_config.5] tidy up the refs to PATTERNS;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/24 10:25:14Damien Miller
[ssh_config.5] add section on patterns; from dtucker + myself
2006-03-15 - jmc@cvs.openbsd.org 2006/02/19 20:12:25Damien Miller
[ssh_config.5] add some vertical space;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/12 10:49:44Damien Miller
[ssh_config.5] slight rewording; ok djm
2006-03-15 - djm@cvs.openbsd.org 2006/02/12 06:45:34Damien Miller
[ssh.c ssh_config.5] add a %l expansion code to the ControlPath, which is filled in with the local hostname at runtime. Requested by henning@ to avoid some problems with /home on NFS; ok dtucker@
2006-01-31 - jmc@cvs.openbsd.org 2006/01/20 11:21:45Damien Miller
[ssh_config.5] - word change, agreed w/ markus - consistency fixes
2006-01-20 - dtucker@cvs.openbsd.org 2006/01/20 00:14:55Darren Tucker
[scp.1 ssh.1 ssh_config.5 sftp.1] Document RekeyLimit. Based on patch from jan.iven at cern.ch from mindrot #1056 with feedback from jmc, djm and markus; ok jmc@ djm@
2006-01-14 - jmc@cvs.openbsd.org 2006/01/12 22:26:02Damien Miller
[ssh_config.5] refer to TCP forwarding, rather than TCP/IP forwarding;
2006-01-03 - (djm) OpenBSD CVS SyncDamien Miller
- jmc@cvs.openbsd.org 2006/01/02 17:09:49 [ssh_config.5 sshd_config.5] some corrections from michael knudsen;
2005-12-24 - jmc@cvs.openbsd.org 2005/12/22 10:31:40Damien Miller
[ssh_config.5] put the description of "UsePrivilegedPort" in the correct place;
2005-12-20 - stevesk@cvs.openbsd.org 2005/12/17 21:36:42Darren Tucker
[ssh_config.5] spelling: intented -> intended