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2010-01-04Remove/adjust manual page references to BSD-specific /etc/rc (closes:Colin Watson
#513417).
2010-01-04Remove manual page references to login.conf, which aren't applicable onColin Watson
non-BSD systems (closes: #154434).
2010-01-01* New upstream release (closes: #536182). Yes, I know 5.3p1 has been outColin Watson
for a while, but there's no GSSAPI patch available for it yet. - Change the default cipher order to prefer the AES CTR modes and the revised "arcfour256" mode to CBC mode ciphers that are susceptible to CPNI-957037 "Plaintext Recovery Attack Against SSH". - Add countermeasures to mitigate CPNI-957037-style attacks against the SSH protocol's use of CBC-mode ciphers. Upon detection of an invalid packet length or Message Authentication Code, ssh/sshd will continue reading up to the maximum supported packet length rather than immediately terminating the connection. This eliminates most of the known differences in behaviour that leaked information about the plaintext of injected data which formed the basis of this attack (closes: #506115, LP: #379329). - ForceCommand directive now accepts commandline arguments for the internal-sftp server (closes: #524423, LP: #362511). - Add AllowAgentForwarding to available Match keywords list (closes: #540623). - Make ssh(1) send the correct channel number for SSH2_MSG_CHANNEL_SUCCESS and SSH2_MSG_CHANNEL_FAILURE messages to avoid triggering 'Non-public channel' error messages on sshd(8) in openssh-5.1. - Avoid printing 'Non-public channel' warnings in sshd(8), since the ssh(1) has sent incorrect channel numbers since ~2004 (this reverts a behaviour introduced in openssh-5.1; closes: #496017). * Update to GSSAPI patch from http://www.sxw.org.uk/computing/patches/openssh-5.2p1-gsskex-all-20090726.patch, including cascading credentials support (LP: #416958).
2008-11-03 - jmc@cvs.openbsd.org 2008/10/03 13:08:12Damien Miller
[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
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.
2008-07-02 - djm@cvs.openbsd.org 2008/07/02 02:24:18Darren Tucker
[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@
2008-06-13 - jmc@cvs.openbsd.org 2008/06/11 07:30:37Darren Tucker
[sshd.8] kill trailing whitespace;
2008-06-11 - djm@cvs.openbsd.org 2008/06/10 23:06:19Darren Tucker
[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@
2008-06-10 - jmc@cvs.openbsd.org 2008/06/10 08:17:40Darren Tucker
[sshd.8 sshd.c] - update usage() - fix SYNOPSIS, and sort options - some minor additional fixes
2008-06-10 - dtucker@cvs.openbsd.org 2008/06/10 04:50:25Darren Tucker
[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
2008-06-08Add cross-references to ssh-vulnkey(1) to ssh(1), ssh-add(1),Colin Watson
ssh-keygen(1), and sshd(8) (closes: #484451).
2008-04-06Backport from 4.9p1:Colin Watson
- Ignore ~/.ssh/rc if a sshd_config ForcedCommand is specified (see http://www.securityfocus.com/bid/28531/info). - Add no-user-rc authorized_keys option to disable execution of ~/.ssh/rc.
2008-04-03 - jmc@cvs.openbsd.org 2008/03/27 22:37:57Damien Miller
[sshd.8] remove trailing whitespace;
2008-03-27 - djm@cvs.openbsd.org 2008/03/26 21:28:14Damien Miller
[auth-options.c auth-options.h session.c sshd.8] add no-user-rc authorized_keys option to disable execution of ~/.ssh/rc
2008-03-27 - jmc@cvs.openbsd.org 2008/02/11 07:58:28Damien Miller
[ssh.1 sshd.8 sshd_config.5] bump Mdocdate for pages committed in "febuary", necessary because of a typo in rcs.c;
2008-02-10 - mcbride@cvs.openbsd.org 2008/02/09 12:15:43Damien Miller
[ssh.1 sshd.8] Document the correct permissions for the ~/.ssh/ directory. ok jmc
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).
2007-12-23Import OpenSSH 4.7p1.Colin Watson
2007-08-17 - (dtucker) [sshd.8] Many Linux variants use a single "!" to denote lockedDarren Tucker
accounts and that's what the code looks for, so make man page and code agree. Pointed out by Roumen Petrov.
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 - 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.)
2007-03-21 - jmc@cvs.openbsd.org 2007/03/20 15:57:15Darren Tucker
[sshd.8] - let synopsis and description agree for -f - sort FILES - +.Xr ssh-keyscan 1 , from Igor Sobrado
2006-08-30 - dtucker@cvs.openbsd.org 2006/08/21 08:15:57Damien Miller
[sshd.8] Add more detail about what permissions are and aren't accepted for authorized_keys files. Corrections jmc@, ok djm@, "looks good" jmc@
2006-07-24 - dtucker@cvs.openbsd.org 2006/07/19 13:07:10Damien Miller
[servconf.c servconf.h session.c sshd.8 sshd_config sshd_config.5] Add ForceCommand keyword to sshd_config, equivalent to the "command=" key option, man page entry and example in sshd_config. Feedback & ok djm@, man page corrections & ok jmc@
2006-07-12 - jmc@cvs.openbsd.org 2006/07/10 16:04:21Darren Tucker
[sshd.8] s/and and/and/
2006-07-10 - dtucker@cvs.openbsd.org 2006/07/10 12:46:51Darren Tucker
[misc.c misc.h sshd.8 sshconnect.c] Add port identifier to known_hosts for non-default ports, based originally on a patch from Devin Nate in bz#910. For any connection using the default port or using a HostKeyAlias the format is unchanged, otherwise the host name or address is enclosed within square brackets in the same format as sshd's ListenAddress. Tested by many, ok markus@.
2006-05-12Merge 4.3p2 to the trunk.Colin Watson
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 10:39:52Damien Miller
[sshd.8] signpost to PATTERNS section;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/19 20:05:00Damien Miller
[sshd.8] grammar;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/19 20:02:17Damien Miller
[sshd.8] sync the (s)hosts.equiv FILES entries w/ those from ssh.1;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/19 19:52:10Damien Miller
[sshd.8] move the sshrc stuff out of FILES, and into its own section: FILES is not a good place to document how stuff works;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/16 09:05:34Damien Miller
[sshd.8] sync some of the FILES entries w/ ssh.1;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/15 16:55:33Damien Miller
[sshd.8] remove ietf draft references; RFC list now maintained in ssh.1;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/13 11:27:25Damien Miller
[sshd.8] sort FILES and use a -compact list;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/13 11:08:43Damien Miller
[sshd.8] - avoid nasty line split - `*' does not need to be escaped
2006-03-15 - jmc@cvs.openbsd.org 2006/02/13 11:02:26Damien Miller
[sshd.8] turn this into an example ssh_known_hosts file; ok djm
2006-03-15 - jmc@cvs.openbsd.org 2006/02/13 10:21:25Damien Miller
[sshd.8] small tweaks for the ssh_known_hosts section;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/13 10:16:39Damien Miller
[sshd.8] no need to subsection the authorized_keys examples - instead, convert this to look like an actual file. also use proto 2 keys, and use IETF example addresses;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/12 17:57:19Damien Miller
[sshd.8] sort the list of options permissable w/ authorized_keys; ok djm dtucker
2006-03-15 - jmc@cvs.openbsd.org 2006/02/12 10:52:41Damien Miller
[sshd.8] rework the description of authorized_keys a little;
2006-03-15 - jmc@cvs.openbsd.org 2006/02/09 10:10:47Damien Miller
[sshd.8] - move some text into a CAVEATS section - merge the COMMAND EXECUTION... section into AUTHENTICATION
2006-02-01 - jmc@cvs.openbsd.org 2006/02/01 09:11:41Damien Miller
[sshd.8] small tweak;
2006-02-01 - (djm) OpenBSD CVS SyncDamien Miller
- jmc@cvs.openbsd.org 2006/02/01 09:06:50 [sshd.8] - merge sections on protocols 1 and 2 into a single section - remove configuration file section ok markus
2006-01-31 - jmc@cvs.openbsd.org 2006/01/25 09:07:22Damien Miller
[sshd.8] move subsections to full sections;
2006-01-31 - jmc@cvs.openbsd.org 2006/01/25 09:04:34Damien Miller
[sshd.8] move the options description up the page, and a few additional tweaks whilst in here; ok markus
2006-01-14 - jmc@cvs.openbsd.org 2006/01/12 22:20:00Damien Miller
[sshd.8] refer to TCP forwarding, rather than TCP/IP forwarding;
2005-12-24 - stevesk@cvs.openbsd.org 2005/12/21 22:44:26Damien Miller
[sshd.8] clarify precedence of -p, Port, ListenAddress; ok and help jmc@
2005-12-13 - reyk@cvs.openbsd.org 2005/12/06 22:38:28Damien Miller
[auth-options.c auth-options.h channels.c channels.h clientloop.c] [misc.c misc.h readconf.c readconf.h scp.c servconf.c servconf.h] [serverloop.c sftp.c ssh.1 ssh.c ssh_config ssh_config.5 sshconnect.c] [sshconnect.h sshd.8 sshd_config sshd_config.5] Add support for tun(4) forwarding over OpenSSH, based on an idea and initial channel code bits by markus@. This is a simple and easy way to use OpenSSH for ad hoc virtual private network connections, e.g. administrative tunnels or secure wireless access. It's based on a new ssh channel and works similar to the existing TCP forwarding support, except that it depends on the tun(4) network interface on both ends of the connection for layer 2 or layer 3 tunneling. This diff also adds support for LocalCommand in the ssh(1) client. ok djm@, markus@, jmc@ (manpages), tested and discussed with others