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diff --git a/crypto/openssh/sshd.8 b/crypto/openssh/sshd.8 deleted file mode 100644 index a99c4f16273b4..0000000000000 --- a/crypto/openssh/sshd.8 +++ /dev/null @@ -1,811 +0,0 @@ -.\" -*- nroff -*- -.\" -.\" Author: Tatu Ylonen <ylo@cs.hut.fi> -.\" Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland -.\" All rights reserved -.\" -.\" As far as I am concerned, the code I have written for this software -.\" can be used freely for any purpose. Any derived versions of this -.\" software must be clearly marked as such, and if the derived work is -.\" incompatible with the protocol description in the RFC file, it must be -.\" called by a name other than "ssh" or "Secure Shell". -.\" -.\" Copyright (c) 1999,2000 Markus Friedl. All rights reserved. -.\" Copyright (c) 1999 Aaron Campbell. All rights reserved. -.\" Copyright (c) 1999 Theo de Raadt. All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR -.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES -.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. -.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, -.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT -.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF -.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -.\" -.\" $OpenBSD: sshd.8,v 1.194 2003/01/31 21:54:40 jmc Exp $ -.Dd September 25, 1999 -.Dt SSHD 8 -.Os -.Sh NAME -.Nm sshd -.Nd OpenSSH SSH daemon -.Sh SYNOPSIS -.Nm sshd -.Bk -words -.Op Fl deiqtD46 -.Op Fl b Ar bits -.Op Fl f Ar config_file -.Op Fl g Ar login_grace_time -.Op Fl h Ar host_key_file -.Op Fl k Ar key_gen_time -.Op Fl o Ar option -.Op Fl p Ar port -.Op Fl u Ar len -.Ek -.Sh DESCRIPTION -.Nm -(SSH Daemon) is the daemon program for -.Xr ssh 1 . -Together these programs replace rlogin and rsh, and -provide secure encrypted communications between two untrusted hosts -over an insecure network. -The programs are intended to be as easy to -install and use as possible. -.Pp -.Nm -is the daemon that listens for connections from clients. -It is normally started at boot from -.Pa /etc/rc . -It forks a new -daemon for each incoming connection. -The forked daemons handle -key exchange, encryption, authentication, command execution, -and data exchange. -This implementation of -.Nm -supports both SSH protocol version 1 and 2 simultaneously. -.Nm -works as follows: -.Pp -.Ss SSH protocol version 1 -.Pp -Each host has a host-specific RSA key -(normally 1024 bits) used to identify the host. -Additionally, when -the daemon starts, it generates a server RSA key (normally 768 bits). -This key is normally regenerated every hour if it has been used, and -is never stored on disk. -.Pp -Whenever a client connects, the daemon responds with its public -host and server keys. -The client compares the -RSA host key against its own database to verify that it has not changed. -The client then generates a 256 bit random number. -It encrypts this -random number using both the host key and the server key, and sends -the encrypted number to the server. -Both sides then use this -random number as a session key which is used to encrypt all further -communications in the session. -The rest of the session is encrypted -using a conventional cipher, currently Blowfish or 3DES, with 3DES -being used by default. -The client selects the encryption algorithm -to use from those offered by the server. -.Pp -Next, the server and the client enter an authentication dialog. -The client tries to authenticate itself using -.Pa .rhosts -authentication, -.Pa .rhosts -authentication combined with RSA host -authentication, RSA challenge-response authentication, or password -based authentication. -.Pp -Rhosts authentication is normally disabled -because it is fundamentally insecure, but can be enabled in the server -configuration file if desired. -System security is not improved unless -.Nm rshd , -.Nm rlogind , -and -.Nm rexecd -are disabled (thus completely disabling -.Xr rlogin -and -.Xr rsh -into the machine). -.Pp -.Ss SSH protocol version 2 -.Pp -Version 2 works similarly: -Each host has a host-specific key (RSA or DSA) used to identify the host. -However, when the daemon starts, it does not generate a server key. -Forward security is provided through a Diffie-Hellman key agreement. -This key agreement results in a shared session key. -.Pp -The rest of the session is encrypted using a symmetric cipher, currently -128 bit AES, Blowfish, 3DES, CAST128, Arcfour, 192 bit AES, or 256 bit AES. -The client selects the encryption algorithm -to use from those offered by the server. -Additionally, session integrity is provided -through a cryptographic message authentication code -(hmac-sha1 or hmac-md5). -.Pp -Protocol version 2 provides a public key based -user (PubkeyAuthentication) or -client host (HostbasedAuthentication) authentication method, -conventional password authentication and challenge response based methods. -.Pp -.Ss Command execution and data forwarding -.Pp -If the client successfully authenticates itself, a dialog for -preparing the session is entered. -At this time the client may request -things like allocating a pseudo-tty, forwarding X11 connections, -forwarding TCP/IP connections, or forwarding the authentication agent -connection over the secure channel. -.Pp -Finally, the client either requests a shell or execution of a command. -The sides then enter session mode. -In this mode, either side may send -data at any time, and such data is forwarded to/from the shell or -command on the server side, and the user terminal in the client side. -.Pp -When the user program terminates and all forwarded X11 and other -connections have been closed, the server sends command exit status to -the client, and both sides exit. -.Pp -.Nm -can be configured using command-line options or a configuration -file. -Command-line options override values specified in the -configuration file. -.Pp -.Nm -rereads its configuration file when it receives a hangup signal, -.Dv SIGHUP , -by executing itself with the name it was started as, i.e., -.Pa /usr/sbin/sshd . -.Pp -The options are as follows: -.Bl -tag -width Ds -.It Fl b Ar bits -Specifies the number of bits in the ephemeral protocol version 1 -server key (default 768). -.It Fl d -Debug mode. -The server sends verbose debug output to the system -log, and does not put itself in the background. -The server also will not fork and will only process one connection. -This option is only intended for debugging for the server. -Multiple -.Fl d -options increase the debugging level. -Maximum is 3. -.It Fl e -When this option is specified, -.Nm -will send the output to the standard error instead of the system log. -.It Fl f Ar configuration_file -Specifies the name of the configuration file. -The default is -.Pa /etc/ssh/sshd_config . -.Nm -refuses to start if there is no configuration file. -.It Fl g Ar login_grace_time -Gives the grace time for clients to authenticate themselves (default -120 seconds). -If the client fails to authenticate the user within -this many seconds, the server disconnects and exits. -A value of zero indicates no limit. -.It Fl h Ar host_key_file -Specifies a file from which a host key is read. -This option must be given if -.Nm -is not run as root (as the normal -host key files are normally not readable by anyone but root). -The default is -.Pa /etc/ssh/ssh_host_key -for protocol version 1, and -.Pa /etc/ssh/ssh_host_rsa_key -and -.Pa /etc/ssh/ssh_host_dsa_key -for protocol version 2. -It is possible to have multiple host key files for -the different protocol versions and host key algorithms. -.It Fl i -Specifies that -.Nm -is being run from -.Xr inetd 8 . -.Nm -is normally not run -from inetd because it needs to generate the server key before it can -respond to the client, and this may take tens of seconds. -Clients would have to wait too long if the key was regenerated every time. -However, with small key sizes (e.g., 512) using -.Nm -from inetd may -be feasible. -.It Fl k Ar key_gen_time -Specifies how often the ephemeral protocol version 1 server key is -regenerated (default 3600 seconds, or one hour). -The motivation for regenerating the key fairly -often is that the key is not stored anywhere, and after about an hour, -it becomes impossible to recover the key for decrypting intercepted -communications even if the machine is cracked into or physically -seized. -A value of zero indicates that the key will never be regenerated. -.It Fl o Ar option -Can be used to give options in the format used in the configuration file. -This is useful for specifying options for which there is no separate -command-line flag. -.It Fl p Ar port -Specifies the port on which the server listens for connections -(default 22). -Multiple port options are permitted. -Ports specified in the configuration file are ignored when a -command-line port is specified. -.It Fl q -Quiet mode. -Nothing is sent to the system log. -Normally the beginning, -authentication, and termination of each connection is logged. -.It Fl t -Test mode. -Only check the validity of the configuration file and sanity of the keys. -This is useful for updating -.Nm -reliably as configuration options may change. -.It Fl u Ar len -This option is used to specify the size of the field -in the -.Li utmp -structure that holds the remote host name. -If the resolved host name is longer than -.Ar len , -the dotted decimal value will be used instead. -This allows hosts with very long host names that -overflow this field to still be uniquely identified. -Specifying -.Fl u0 -indicates that only dotted decimal addresses -should be put into the -.Pa utmp -file. -.Fl u0 -may also be used to prevent -.Nm -from making DNS requests unless the authentication -mechanism or configuration requires it. -Authentication mechanisms that may require DNS include -.Cm RhostsAuthentication , -.Cm RhostsRSAAuthentication , -.Cm HostbasedAuthentication -and using a -.Cm from="pattern-list" -option in a key file. -Configuration options that require DNS include using a -USER@HOST pattern in -.Cm AllowUsers -or -.Cm DenyUsers . -.It Fl D -When this option is specified -.Nm -will not detach and does not become a daemon. -This allows easy monitoring of -.Nm sshd . -.It Fl 4 -Forces -.Nm -to use IPv4 addresses only. -.It Fl 6 -Forces -.Nm -to use IPv6 addresses only. -.El -.Sh CONFIGURATION FILE -.Nm -reads configuration data from -.Pa /etc/ssh/sshd_config -(or the file specified with -.Fl f -on the command line). -The file format and configuration options are described in -.Xr sshd_config 5 . -.Sh LOGIN PROCESS -When a user successfully logs in, -.Nm -does the following: -.Bl -enum -offset indent -.It -If the login is on a tty, and no command has been specified, -prints last login time and -.Pa /etc/motd -(unless prevented in the configuration file or by -.Pa $HOME/.hushlogin ; -see the -.Sx FILES -section). -.It -If the login is on a tty, records login time. -.It -Checks -.Pa /etc/nologin ; -if it exists, prints contents and quits -(unless root). -.It -Changes to run with normal user privileges. -.It -Sets up basic environment. -.It -Reads -.Pa $HOME/.ssh/environment -if it exists and users are allowed to change their environment. -See the -.Cm PermitUserEnvironment -option in -.Xr sshd_config 5 . -.It -Changes to user's home directory. -.It -If -.Pa $HOME/.ssh/rc -exists, runs it; else if -.Pa /etc/ssh/sshrc -exists, runs -it; otherwise runs xauth. -The -.Dq rc -files are given the X11 -authentication protocol and cookie in standard input. -.It -Runs user's shell or command. -.El -.Sh AUTHORIZED_KEYS FILE FORMAT -.Pa $HOME/.ssh/authorized_keys -is the default file that lists the public keys that are -permitted for RSA authentication in protocol version 1 -and for public key authentication (PubkeyAuthentication) -in protocol version 2. -.Cm AuthorizedKeysFile -may be used to specify an alternative file. -.Pp -Each line of the file contains one -key (empty lines and lines starting with a -.Ql # -are ignored as -comments). -Each RSA public key consists of the following fields, separated by -spaces: options, bits, exponent, modulus, comment. -Each protocol version 2 public key consists of: -options, keytype, base64 encoded key, comment. -The options field -is optional; its presence is determined by whether the line starts -with a number or not (the options field never starts with a number). -The bits, exponent, modulus and comment fields give the RSA key for -protocol version 1; the -comment field is not used for anything (but may be convenient for the -user to identify the key). -For protocol version 2 the keytype is -.Dq ssh-dss -or -.Dq ssh-rsa . -.Pp -Note that lines in this file are usually several hundred bytes long -(because of the size of the public key encoding). -You don't want to type them in; instead, copy the -.Pa identity.pub , -.Pa id_dsa.pub -or the -.Pa id_rsa.pub -file and edit it. -.Pp -.Nm -enforces a minimum RSA key modulus size for protocol 1 -and protocol 2 keys of 768 bits. -.Pp -The options (if present) consist of comma-separated option -specifications. -No spaces are permitted, except within double quotes. -The following option specifications are supported (note -that option keywords are case-insensitive): -.Bl -tag -width Ds -.It Cm from="pattern-list" -Specifies that in addition to public key authentication, the canonical name -of the remote host must be present in the comma-separated list of -patterns -.Pf ( Ql * -and -.Ql ? -serve as wildcards). -The list may also contain -patterns negated by prefixing them with -.Ql ! ; -if the canonical host name matches a negated pattern, the key is not accepted. -The purpose -of this option is to optionally increase security: public key authentication -by itself does not trust the network or name servers or anything (but -the key); however, if somebody somehow steals the key, the key -permits an intruder to log in from anywhere in the world. -This additional option makes using a stolen key more difficult (name -servers and/or routers would have to be compromised in addition to -just the key). -.It Cm command="command" -Specifies that the command is executed whenever this key is used for -authentication. -The command supplied by the user (if any) is ignored. -The command is run on a pty if the client requests a pty; -otherwise it is run without a tty. -If an 8-bit clean channel is required, -one must not request a pty or should specify -.Cm no-pty . -A quote may be included in the command by quoting it with a backslash. -This option might be useful -to restrict certain public keys to perform just a specific operation. -An example might be a key that permits remote backups but nothing else. -Note that the client may specify TCP/IP and/or X11 -forwarding unless they are explicitly prohibited. -Note that this option applies to shell, command or subsystem execution. -.It Cm environment="NAME=value" -Specifies that the string is to be added to the environment when -logging in using this key. -Environment variables set this way -override other default environment values. -Multiple options of this type are permitted. -Environment processing is disabled by default and is -controlled via the -.Cm PermitUserEnvironment -option. -This option is automatically disabled if -.Cm UseLogin -is enabled. -.It Cm no-port-forwarding -Forbids TCP/IP forwarding when this key is used for authentication. -Any port forward requests by the client will return an error. -This might be used, e.g., in connection with the -.Cm command -option. -.It Cm no-X11-forwarding -Forbids X11 forwarding when this key is used for authentication. -Any X11 forward requests by the client will return an error. -.It Cm no-agent-forwarding -Forbids authentication agent forwarding when this key is used for -authentication. -.It Cm no-pty -Prevents tty allocation (a request to allocate a pty will fail). -.It Cm permitopen="host:port" -Limit local -.Li ``ssh -L'' -port forwarding such that it may only connect to the specified host and -port. -IPv6 addresses can be specified with an alternative syntax: -.Ar host/port . -Multiple -.Cm permitopen -options may be applied separated by commas. No pattern matching is -performed on the specified hostnames, they must be literal domains or -addresses. -.El -.Ss Examples -1024 33 12121.\|.\|.\|312314325 ylo@foo.bar -.Pp -from="*.niksula.hut.fi,!pc.niksula.hut.fi" 1024 35 23.\|.\|.\|2334 ylo@niksula -.Pp -command="dump /home",no-pty,no-port-forwarding 1024 33 23.\|.\|.\|2323 backup.hut.fi -.Pp -permitopen="10.2.1.55:80",permitopen="10.2.1.56:25" 1024 33 23.\|.\|.\|2323 -.Sh SSH_KNOWN_HOSTS FILE FORMAT -The -.Pa /etc/ssh/ssh_known_hosts -and -.Pa $HOME/.ssh/known_hosts -files contain host public keys for all known hosts. -The global file should -be prepared by the administrator (optional), and the per-user file is -maintained automatically: whenever the user connects from an unknown host -its key is added to the per-user file. -.Pp -Each line in these files contains the following fields: hostnames, -bits, exponent, modulus, comment. -The fields are separated by spaces. -.Pp -Hostnames is a comma-separated list of patterns ('*' and '?' act as -wildcards); each pattern in turn is matched against the canonical host -name (when authenticating a client) or against the user-supplied -name (when authenticating a server). -A pattern may also be preceded by -.Ql ! -to indicate negation: if the host name matches a negated -pattern, it is not accepted (by that line) even if it matched another -pattern on the line. -.Pp -Bits, exponent, and modulus are taken directly from the RSA host key; they -can be obtained, e.g., from -.Pa /etc/ssh/ssh_host_key.pub . -The optional comment field continues to the end of the line, and is not used. -.Pp -Lines starting with -.Ql # -and empty lines are ignored as comments. -.Pp -When performing host authentication, authentication is accepted if any -matching line has the proper key. -It is thus permissible (but not -recommended) to have several lines or different host keys for the same -names. -This will inevitably happen when short forms of host names -from different domains are put in the file. -It is possible -that the files contain conflicting information; authentication is -accepted if valid information can be found from either file. -.Pp -Note that the lines in these files are typically hundreds of characters -long, and you definitely don't want to type in the host keys by hand. -Rather, generate them by a script -or by taking -.Pa /etc/ssh/ssh_host_key.pub -and adding the host names at the front. -.Ss Examples -.Bd -literal -closenet,.\|.\|.\|,130.233.208.41 1024 37 159.\|.\|.93 closenet.hut.fi -cvs.openbsd.org,199.185.137.3 ssh-rsa AAAA1234.....= -.Ed -.Sh FILES -.Bl -tag -width Ds -.It Pa /etc/ssh/sshd_config -Contains configuration data for -.Nm sshd . -The file format and configuration options are described in -.Xr sshd_config 5 . -.It Pa /etc/ssh/ssh_host_key, /etc/ssh/ssh_host_dsa_key, /etc/ssh/ssh_host_rsa_key -These three files contain the private parts of the host keys. -These files should only be owned by root, readable only by root, and not -accessible to others. -Note that -.Nm -does not start if this file is group/world-accessible. -.It Pa /etc/ssh/ssh_host_key.pub, /etc/ssh/ssh_host_dsa_key.pub, /etc/ssh/ssh_host_rsa_key.pub -These three files contain the public parts of the host keys. -These files should be world-readable but writable only by -root. -Their contents should match the respective private parts. -These files are not -really used for anything; they are provided for the convenience of -the user so their contents can be copied to known hosts files. -These files are created using -.Xr ssh-keygen 1 . -.It Pa /etc/moduli -Contains Diffie-Hellman groups used for the "Diffie-Hellman Group Exchange". -The file format is described in -.Xr moduli 5 . -.It Pa /var/empty -.Xr chroot 2 -directory used by -.Nm -during privilege separation in the pre-authentication phase. -The directory should not contain any files and must be owned by root -and not group or world-writable. -.It Pa /var/run/sshd.pid -Contains the process ID of the -.Nm -listening for connections (if there are several daemons running -concurrently for different ports, this contains the process ID of the one -started last). -The content of this file is not sensitive; it can be world-readable. -.It Pa $HOME/.ssh/authorized_keys -Lists the public keys (RSA or DSA) that can be used to log into the user's account. -This file must be readable by root (which may on some machines imply -it being world-readable if the user's home directory resides on an NFS -volume). -It is recommended that it not be accessible by others. -The format of this file is described above. -Users will place the contents of their -.Pa identity.pub , -.Pa id_dsa.pub -and/or -.Pa id_rsa.pub -files into this file, as described in -.Xr ssh-keygen 1 . -.It Pa "/etc/ssh/ssh_known_hosts" and "$HOME/.ssh/known_hosts" -These files are consulted when using rhosts with RSA host -authentication or protocol version 2 hostbased authentication -to check the public key of the host. -The key must be listed in one of these files to be accepted. -The client uses the same files -to verify that it is connecting to the correct remote host. -These files should be writable only by root/the owner. -.Pa /etc/ssh/ssh_known_hosts -should be world-readable, and -.Pa $HOME/.ssh/known_hosts -can, but need not be, world-readable. -.It Pa /etc/nologin -If this file exists, -.Nm -refuses to let anyone except root log in. -The contents of the file -are displayed to anyone trying to log in, and non-root connections are -refused. -The file should be world-readable. -.It Pa /etc/hosts.allow, /etc/hosts.deny -Access controls that should be enforced by tcp-wrappers are defined here. -Further details are described in -.Xr hosts_access 5 . -.It Pa $HOME/.rhosts -This file contains host-username pairs, separated by a space, one per -line. -The given user on the corresponding host is permitted to log in -without a password. -The same file is used by rlogind and rshd. -The file must -be writable only by the user; it is recommended that it not be -accessible by others. -.Pp -If is also possible to use netgroups in the file. -Either host or user -name may be of the form +@groupname to specify all hosts or all users -in the group. -.It Pa $HOME/.shosts -For ssh, -this file is exactly the same as for -.Pa .rhosts . -However, this file is -not used by rlogin and rshd, so using this permits access using SSH only. -.It Pa /etc/hosts.equiv -This file is used during -.Pa .rhosts -authentication. -In the simplest form, this file contains host names, one per line. -Users on -those hosts are permitted to log in without a password, provided they -have the same user name on both machines. -The host name may also be -followed by a user name; such users are permitted to log in as -.Em any -user on this machine (except root). -Additionally, the syntax -.Dq +@group -can be used to specify netgroups. -Negated entries start with -.Ql \&- . -.Pp -If the client host/user is successfully matched in this file, login is -automatically permitted provided the client and server user names are the -same. -Additionally, successful RSA host authentication is normally required. -This file must be writable only by root; it is recommended -that it be world-readable. -.Pp -.Sy "Warning: It is almost never a good idea to use user names in" -.Pa hosts.equiv . -Beware that it really means that the named user(s) can log in as -.Em anybody , -which includes bin, daemon, adm, and other accounts that own critical -binaries and directories. -Using a user name practically grants the user root access. -The only valid use for user names that I can think -of is in negative entries. -.Pp -Note that this warning also applies to rsh/rlogin. -.It Pa /etc/shosts.equiv -This is processed exactly as -.Pa /etc/hosts.equiv . -However, this file may be useful in environments that want to run both -rsh/rlogin and ssh. -.It Pa $HOME/.ssh/environment -This file is read into the environment at login (if it exists). -It can only contain empty lines, comment lines (that start with -.Ql # ) , -and assignment lines of the form name=value. -The file should be writable -only by the user; it need not be readable by anyone else. -Environment processing is disabled by default and is -controlled via the -.Cm PermitUserEnvironment -option. -.It Pa $HOME/.ssh/rc -If this file exists, it is run with -.Pa /bin/sh -after reading the -environment files but before starting the user's shell or command. -It must not produce any output on stdout; stderr must be used -instead. -If X11 forwarding is in use, it will receive the "proto cookie" pair in -its standard input (and -.Ev DISPLAY -in its environment). -The script must call -.Xr xauth 1 -because -.Nm -will not run xauth automatically to add X11 cookies. -.Pp -The primary purpose of this file is to run any initialization routines -which may be needed before the user's home directory becomes -accessible; AFS is a particular example of such an environment. -.Pp -This file will probably contain some initialization code followed by -something similar to: -.Bd -literal -if read proto cookie && [ -n "$DISPLAY" ]; then - if [ `echo $DISPLAY | cut -c1-10` = 'localhost:' ]; then - # X11UseLocalhost=yes - echo add unix:`echo $DISPLAY | - cut -c11-` $proto $cookie - else - # X11UseLocalhost=no - echo add $DISPLAY $proto $cookie - fi | xauth -q - -fi -.Ed -.Pp -If this file does not exist, -.Pa /etc/ssh/sshrc -is run, and if that -does not exist either, xauth is used to add the cookie. -.Pp -This file should be writable only by the user, and need not be -readable by anyone else. -.It Pa /etc/ssh/sshrc -Like -.Pa $HOME/.ssh/rc . -This can be used to specify -machine-specific login-time initializations globally. -This file should be writable only by root, and should be world-readable. -.El -.Sh AUTHORS -OpenSSH is a derivative of the original and free -ssh 1.2.12 release by Tatu Ylonen. -Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos, -Theo de Raadt and Dug Song -removed many bugs, re-added newer features and -created OpenSSH. -Markus Friedl contributed the support for SSH -protocol versions 1.5 and 2.0. -Niels Provos and Markus Friedl contributed support -for privilege separation. -.Sh SEE ALSO -.Xr scp 1 , -.Xr sftp 1 , -.Xr ssh 1 , -.Xr ssh-add 1 , -.Xr ssh-agent 1 , -.Xr ssh-keygen 1 , -.Xr login.conf 5 , -.Xr moduli 5 , -.Xr sshd_config 5 , -.Xr sftp-server 8 -.Rs -.%A T. Ylonen -.%A T. Kivinen -.%A M. Saarinen -.%A T. Rinne -.%A S. Lehtinen -.%T "SSH Protocol Architecture" -.%N draft-ietf-secsh-architecture-12.txt -.%D January 2002 -.%O work in progress material -.Re -.Rs -.%A M. Friedl -.%A N. Provos -.%A W. A. Simpson -.%T "Diffie-Hellman Group Exchange for the SSH Transport Layer Protocol" -.%N draft-ietf-secsh-dh-group-exchange-02.txt -.%D January 2002 -.%O work in progress material -.Re |