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sshd.openssh (1m)

名前

sshd.openssh - OpenSSH SSH daemon

形式

sshd  [-46DdeiqTt]  [-b  bits]  [-C  connection_spec] [-c host_certifi-
cate_file] [-E log_file] [-f  config_file]  [-g  login_grace_time]  [-h
host_key_file] [-k key_gen_time] [-o option] [-p port] [-u len]

説明

SSHD(1M)                                                              SSHD(1M)



NAME
       sshd - OpenSSH SSH daemon

SYNOPSIS
       sshd  [-46DdeiqTt]  [-b  bits]  [-C  connection_spec] [-c host_certifi-
       cate_file] [-E log_file] [-f  config_file]  [-g  login_grace_time]  [-h
       host_key_file] [-k key_gen_time] [-o option] [-p port] [-u len]

DESCRIPTION
       sshd (OpenSSH Daemon) is the daemon program for ssh(1).  Together these
       programs replace rlogin(1) and rsh(1),  and  provide  secure  encrypted
       communications between two untrusted hosts over an insecure network.

       sshd  listens  for connections from clients.  It is normally started at
       boot from /etc/rc.  It forks a new daemon for each incoming connection.
       The  forked  daemons  handle  key exchange, encryption, authentication,
       command execution, and data exchange.

       sshd can be configured using command-line options  or  a  configuration
       file (by default sshd_config(4)) ; command-line options override values
       specified in the configuration file.  sshd  rereads  its  configuration
       file when it receives a hangup signal, SIGHUP, by executing itself with
       the name and options it was started with, e.g. /usr/sbin/sshd.

       The options are as follows:

       -4     Forces sshd to use IPv4 addresses only.

       -6     Forces sshd to use IPv6 addresses only.

       -b bits
              Specifies the number of bits in the ephemeral protocol version 1
              server key (default 1024).

       -C connection_spec
              Specify  the  connection  parameters  to use for the -T extended
              test mode.  If provided, any Match directives in the  configura-
              tion  file  that  would  apply  to the specified user, host, and
              address will be set before the configuration is written to stan-
              dard  output.   The  connection  parameters are supplied as key-
              word=value  pairs.   The  keywords   are   ``user'',   ``host'',
              ``laddr'', ``lport'', and ``addr''.  All are required and may be
              supplied in any order, either with multiple -C options or  as  a
              comma-separated list.

       -c host_certificate_file
              Specifies  a  path to a certificate file to identify sshd during
              key exchange.  The certificate file must match a host  key  file
              specified  using  the  -h  option  or  the HostKey configuration
              directive.

       -D     When this option is specified, sshd will not detach and does not
              become a daemon.  This allows easy monitoring of sshd.

       -d     Debug  mode.   The server sends verbose debug output to standard
              error, 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
              -d options increase the debugging level.  Maximum is 3.

       -E log_file
              Append debug logs to log_file instead of the system log.

       -e     Write debug logs to standard error instead of the system log.

       -f config_file
              Specifies  the  name  of the configuration file.  The default is
              /etc/ssh/sshd_config.  sshd refuses to start if there is no con-
              figuration file.

       -g 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.

       -h host_key_file
              Specifies a file from which a host key  is  read.   This  option
              must be given if sshd is not run as root (as the normal host key
              files are normally  not  readable  by  anyone  but  root).   The
              default  is  /etc/ssh/ssh_host_key  for  protocol version 1, and
              /etc/ssh/ssh_host_dsa_key,  and  /etc/ssh/ssh_host_rsa_key   for
              protocol  version  2.   It is possible to have multiple host key
              files for the different protocol versions  and  host  key  algo-
              rithms.

       -i     Specifies  that  sshd  is being run from inetd(8).  sshd is nor-
              mally 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 sshd from inetd may be feasible.

       -k key_gen_time
              Specifies how often the ephemeral protocol version 1 server  key
              is regenerated (default 3600 seconds, or one hour).  The motiva-
              tion for regenerating the key fairly often is that  the  key  is
              not stored anywhere, and after about an hour it becomes impossi-
              ble 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.

       -o option
              Can be used to give options in the format used in the configura-
              tion  file.   This  is  useful  for specifying options for which
              there is no separate command-line flag.  For full details of the
              options, and their values, see sshd_config(4).

       -p port
              Specifies  the  port on which the server listens for connections
              (default 22).  Multiple port options are permitted.  Ports spec-
              ified in the configuration file with the Port option are ignored
              when a command-line port is specified.   Ports  specified  using
              the ListenAddress option override command-line ports.

       -q     Quiet  mode.   Nothing  is sent to the system log.  Normally the
              beginning, authentication, and termination of each connection is
              logged.

       -T     Extended  test  mode.   Check  the validity of the configuration
              file, output the effective  configuration  to  stdout  and  then
              exit.   Optionally, Match rules may be applied by specifying the
              connection parameters using one or more -C options.

       -t     Test mode.  Only check the validity of  the  configuration  file
              and  sanity of the keys.  This is useful for updating sshd reli-
              ably as configuration options may change.

       -u len This option is used to specify the size of the field in the utmp
              structure that holds the remote host name.  If the resolved host
              name is longer than len, the dotted decimal value will  be  used
              instead.  This allows hosts with very long host names that over-
              flow this field to still be uniquely identified.  Specifying -u0
              indicates  that only dotted decimal addresses should be put into
              the utmp file.  -u0 may also be used to prevent sshd from making
              DNS  requests  unless the authentication mechanism or configura-
              tion requires it.  Authentication mechanisms  that  may  require
              DNS  include  RhostsRSAAuthentication,  HostbasedAuthentication,
              and using a from="pattern-list" option in a key file.   Configu-
              ration  options  that require DNS include using a USER@HOST pat-
              tern in AllowUsers or DenyUsers.

AUTHENTICATION
       The OpenSSH SSH daemon supports SSH protocols 1 and 2.  The default  is
       to  use  protocol  2  only, though this can be changed via the Protocol
       option in sshd_config(4).  Protocol 2 supports DSA and RSA keys; proto-
       col  1  only  supports  RSA  keys.  For both protocols, each host has a
       host-specific key, normally 2048 bits, used to identify the host.

       Forward security for protocol  1  is  provided  through  an  additional
       server  key, normally 768 bits, generated when the server starts.  This
       key is normally regenerated every hour if it  has  been  used,  and  is
       never  stored on disk.  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.

       For  protocol  2, forward security is provided through a Diffie-Hellman
       key agreement.  This key agreement results in  a  shared  session  key.
       The  rest  of  the  session is encrypted using a symmetric cipher, cur-
       rently 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  pro-
       vided  through  a  cryptographic message authentication code (hmac-md5,
       hmac-sha1, umac-64, umac-128, hmac-ripemd160,  hmac-sha2-256  or  hmac-
       sha2-512).

       Finally, the server and the client enter an authentication dialog.  The
       client tries to authenticate itself  using  host-based  authentication,
       public  key authentication, challenge-response authentication, or pass-
       word authentication.

       Regardless of the authentication type, the account is checked to ensure
       that  it  is accessible.  An account is not accessible if it is locked,
       listed in DenyUsers or its group is listed in DenyGroups .  The defini-
       tion of a locked account is system dependant. Some platforms have their
       own account database (eg AIX) and some modify the passwd field ( `*LK*'
       on Solaris and UnixWare, `*' on HP-UX, containing `Nologin' on Tru64, a
       leading `*LOCKED*' on FreeBSD and a leading `!'  on most Linuxes).   If
       there  is  a  requirement  to  disable  password authentication for the
       account while allowing still public-key, then the passwd  field  should
       be set to something other than these values (eg `NP' or `*NP*' ).

       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 connections, or forwarding the authentication agent connection over
       the secure channel.

       After  this,  the client either requests a shell or execution of a com-
       mand.  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.

       When  the  user program terminates and all forwarded X11 and other con-
       nections have been closed, the server sends command exit status to  the
       client, and both sides exit.

LOGIN PROCESS
       When a user successfully logs in, sshd does the following:

       1.     If  the  login  is  on a tty, and no command has been specified,
              prints last login time and /etc/motd (unless  prevented  in  the
              configuration file or by ~/.hushlogin; see the FILES section).

       2.     If the login is on a tty, records login time.

       3.     Checks  /etc/nologin;  if  it  exists, prints contents and quits
              (unless root).

       4.     Changes to run with normal user privileges.

       5.     Sets up basic environment.

       6.     Reads the file ~/.ssh/environment, if it exists, and  users  are
              allowed to change their environment.  See the PermitUserEnviron-
              ment option in sshd_config(4).

       7.     Changes to user's home directory.

       8.     If ~/.ssh/rc exists, runs it;  else  if  /etc/ssh/sshrc  exists,
              runs  it;  otherwise runs xauth.  The ``rc'' files are given the
              X11 authentication protocol and cookie in standard  input.   See
              SSHRC , below.

       9.     Runs user's shell or command.

SSHRC
       If  the file ~/.ssh/rc exists, sh(1) runs it after reading the environ-
       ment 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 DISPLAY in its environment).  The script must call
       xauth(1) because sshd will not run xauth automatically to add X11 cook-
       ies.

       The  primary purpose of this file is to run any initialization routines
       which may be needed before the user's home directory  becomes  accessi-
       ble; AFS is a particular example of such an environment.

       This  file  will  probably contain some initialization code followed by
       something similar to:

       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

       If this file does not exist, /etc/ssh/sshrc is run, and  if  that  does
       not exist either, xauth is used to add the cookie.

AUTHORIZED_KEYS FILE FORMAT
       AuthorizedKeysFile  specifies the files containing public keys for pub-
       lic  key  authentication;  if  none  is  specified,  the   default   is
       ~/.ssh/authorized_keys  and  ~/.ssh/authorized_keys2.  Each line of the
       file contains one key (empty lines and lines starting with  a  `#'  are
       ignored  as comments).  Protocol 1 public keys consist of the following
       space-separated fields:  options,  bits,  exponent,  modulus,  comment.
       Protocol 2 public key consist 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 ``ssh-dss'' or ``ssh-rsa''.

       Note  that  lines  in  this file are usually several hundred bytes long
       (because of the size of the public key encoding) up to  a  limit  of  8
       kilobytes,  which  permits DSA keys up to 8 kilobits and RSA keys up to
       16 kilobits.  You don't want to type them in; instead, copy  the  iden-
       tity.pub, id_dsa.pub, or the id_rsa.pub file and edit it.

       sshd  enforces a minimum RSA key modulus size for protocol 1 and proto-
       col 2 keys of 768 bits.

       The options (if present) consist of comma-separated  option  specifica-
       tions.  No spaces are permitted, except within double quotes.  The fol-
       lowing option specifications are supported (note that  option  keywords
       are case-insensitive):

       cert-authority
              Specifies  that the listed key is a certification authority (CA)
              that is trusted to validate signed certificates for user authen-
              tication.

              Certificates may encode access restrictions similar to these key
              options.  If both certificate restrictions and key  options  are
              present, the most restrictive union of the two is applied.

       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 spec-
              ify 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 and/or X11  forward-
              ing  unless  they are explicitly prohibited.  The command origi-
              nally supplied by the client  is  available  in  the  SSH_ORIGI-
              NAL_COMMAND environment variable.  Note that this option applies
              to shell, command or subsystem execution.  Also note  that  this
              command  may  be superseded by either a sshd_config(4) ForceCom-
              mand directive or a command embedded in a certificate.

       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 PermitUserEnvironment  option.
              This option is automatically disabled if UseLogin is enabled.

       from="pattern-list"
              Specifies  that in addition to public key authentication, either
              the canonical name of the remote host or its IP address must  be
              present  in  the comma-separated list of patterns.  See PATTERNS
              in ssh_config(4) for more information on patterns.

              In addition to the wildcard matching  that  may  be  applied  to
              hostnames  or  addresses,  a  from stanza may match IP addresses
              using CIDR address/masklen notation.

              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).

       no-agent-forwarding
              Forbids authentication agent forwarding when this  key  is  used
              for authentication.

       no-port-forwarding
              Forbids TCP 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 command option.

       no-pty Prevents tty allocation (a request to allocate a pty will fail).

       no-user-rc
              Disables execution of ~/.ssh/rc.

       no-X11-forwarding
              Forbids X11 forwarding when this key is used for authentication.
              Any X11 forward requests by the client will return an error.

       permitopen="host:port"
              Limit local ``ssh -L'' port forwarding such  that  it  may  only
              connect  to  the specified host and port.  IPv6 addresses can be
              specified by enclosing the address in square brackets.  Multiple
              permitopen  options may be applied separated by commas.  No pat-
              tern matching is performed on the specified hostnames, they must
              be  literal  domains  or  addresses.   A port specification of *
              matches any port.

       principals="principals"
              On a cert-authority line, specifies allowed principals for  cer-
              tificate authentication as a comma-separated list.  At least one
              name from the list must appear  in  the  certificate's  list  of
              principals  for  the certificate to be accepted.  This option is
              ignored for keys that are  not  marked  as  trusted  certificate
              signers using the cert-authority option.

       tunnel="n"
              Force  a  tun(4) device on the server.  Without this option, the
              next available device will be used if the client requests a tun-
              nel.

              An example authorized_keys file:

              # Comments allowed at start of line
              ssh-rsa AAAAB3Nza...LiPk== user@example.net
              from="*.sales.example.net,!pc.sales.example.net" ssh-rsa
              AAAAB2...19Q== john@example.net
              command="dump /home",no-pty,no-port-forwarding ssh-dss
              AAAAC3...51R== example.net
              permitopen="192.0.2.1:80",permitopen="192.0.2.2:25" ssh-dss
              AAAAB5...21S==
              tunnel="0",command="sh /etc/netstart tun0" ssh-rsa AAAA...==
              jane@example.net

SSH_KNOWN_HOSTS FILE FORMAT
       The  /etc/ssh/ssh_known_hosts and ~/.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 auto-
       matically: whenever the user connects from an unknown host, its key  is
       added to the per-user file.

       Each  line  in  these  files  contains  the  following  fields: markers
       (optional), hostnames, bits, exponent, modulus,  comment.   The  fields
       are separated by spaces.

       The  marker  is  optional,  but if it is present then it must be one of
       ``@cert-authority'', to indicate that the line contains a certification
       authority (CA) key, or ``@revoked'', to indicate that the key contained
       on the line is revoked and must not ever be accepted.  Only one  marker
       should be used on a key line.

       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  `!'
       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.   A hostname or address may optionally be enclosed within `[' and
       `]' brackets then followed by `:' and a non-standard port number.

       Alternately, hostnames may be stored in a hashed form which hides  host
       names  and  addresses  should the file's contents be disclosed.  Hashed
       hostnames start with a `|' character.  Only  one  hashed  hostname  may
       appear  on  a  single  line  and none of the above negation or wildcard
       operators may be applied.

       Bits, exponent, and modulus are taken directly from the RSA  host  key;
       they can be obtained, for example, from /etc/ssh/ssh_host_key.pub.  The
       optional comment field continues to the end of the  line,  and  is  not
       used.

       Lines starting with `#' and empty lines are ignored as comments.

       When  performing host authentication, authentication is accepted if any
       matching line has the proper key; either one that matches  exactly  or,
       if  the  server has presented a certificate for authentication, the key
       of the certification authority that signed the certificate.  For a  key
       to  be  trusted  as a certification authority, it must use the ``@cert-
       authority'' marker described above.

       The known hosts file also provides a facility to mark keys as  revoked,
       for  example  when it is known that the associated private key has been
       stolen.  Revoked keys  are  specified  by  including  the  ``@revoked''
       marker  at  the  beginning  of the key line, and are never accepted for
       authentication or as certification authorities, but instead  will  pro-
       duce a warning from ssh(1) when they are encountered.

       It  is  permissible (but not recommended) to have several lines or dif-
       ferent 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;  authen-
       tication  is  accepted  if  valid  information can be found from either
       file.

       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,  ssh-keyscan(1)  or  by  taking
       /etc/ssh/ssh_host_key.pub and adding the host names at the front.  ssh-
       keygen(1)   also   offers   some   basic    automated    editing    for
       ~/.ssh/known_hosts  including  removing  hosts matching a host name and
       converting all host names to their hashed representations.

       An example ssh_known_hosts file:

       # Comments allowed at start of line
       closenet,...,192.0.2.53 1024 37 159...93 closenet.example.net
       cvs.example.net,192.0.2.10 ssh-rsa AAAA1234.....=
       # A hashed hostname
       |1|JfKTdBh7rNbXkVAQCRp4OQoPfmI=|USECr3SWf1JUPsms5AqfD5QfxkM= ssh-rsa
       AAAA1234.....=
       # A revoked key
       @revoked * ssh-rsa AAAAB5W...
       # A CA key, accepted for any host in *.mydomain.com or *.mydomain.org
       @cert-authority *.mydomain.org,*.mydomain.com ssh-rsa AAAAB5W...

FILES
       ~/.hushlogin
              This file is used to suppress printing the last login  time  and
              /etc/motd,  if  PrintLastLog  and  PrintMotd,  respectively, are
              enabled.  It does not suppress printing of the banner  specified
              by Banner.


       ~/.rhosts
              This  file is used for host-based authentication (see ssh(1) for
              more information).  On some machines this file may  need  to  be
              world-readable  if the user's home directory is on an NFS parti-
              tion, because sshd reads it as root.   Additionally,  this  file
              must  be  owned by the user, and must not have write permissions
              for anyone else.  The recommended permission for  most  machines
              is read/write for the user, and not accessible by others.


       ~/.shosts
              This file is used in exactly the same way as .rhosts, but allows
              host-based  authentication   without   permitting   login   with
              rlogin/rsh.


       ~/.ssh/
              This  directory  is  the  default location for all user-specific
              configuration and authentication information.  There is no  gen-
              eral  requirement  to keep the entire contents of this directory
              secret, but the recommended permissions  are  read/write/execute
              for the user, and not accessible by others.


       ~/.ssh/authorized_keys
              Lists the public keys (DSA, RSA) that can be used for logging in
              as this user.  The format of this file is described above.   The
              content of the file is not highly sensitive, but the recommended
              permissions are read/write for the user, and not  accessible  by
              others.

              If this file, the ~/.ssh directory, or the user's home directory
              are writable by other users, then the file could be modified  or
              replaced  by  unauthorized  users.   In this case, sshd will not
              allow it to be used unless the StrictModes option has  been  set
              to ``no''.


       ~/.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
              `#'  )  , 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 PermitUserEnvironment option.


       ~/.ssh/known_hosts
              Contains a list of host keys for all hosts the user  has  logged
              into  that  are not already in the systemwide list of known host
              keys.  The format of this file is described  above.   This  file
              should  be writable only by root/the owner and can, but need not
              be, world-readable.


       ~/.ssh/rc
              Contains initialization routines to be  run  before  the  user's
              home directory becomes accessible.  This file should be writable
              only by the user, and need not be readable by anyone else.


       /etc/hosts.allow

       /etc/hosts.deny
              Access controls that should  be  enforced  by  tcp-wrappers  are
              defined here.  Further details are described in hosts_access(5).


       /etc/hosts.equiv
              This  file  is  for host-based authentication (see ssh(1)) .  It
              should only be writable by root.


       /etc/ssh/moduli
              Contains Diffie-Hellman  groups  used  for  the  "Diffie-Hellman
              Group Exchange".  The file format is described in moduli(4).


       /etc/motd
              See motd(5).


       /etc/nologin
              If  this file exists, sshd 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.


       /etc/ssh/shosts.equiv
              This file is used in exactly the same way  as  hosts.equiv,  but
              allows  host-based  authentication without permitting login with
              rlogin/rsh.


       /etc/ssh/ssh_host_key

       /etc/ssh/ssh_host_dsa_key

       /etc/ssh/ssh_host_rsa_key
              These 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  sshd  does  not  start  if
              these files are group/world-accessible.


       /etc/ssh/ssh_host_key.pub

       /etc/ssh/ssh_host_dsa_key.pub

       /etc/ssh/ssh_host_rsa_key.pub
              These  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 con-
              venience  of  the  user so their contents can be copied to known
              hosts files.  These files are created using ssh-keygen(1).


       /etc/ssh/ssh_known_hosts
              Systemwide list of known host keys.  This file  should  be  pre-
              pared  by  the  system  administrator to contain the public host
              keys of all machines in the organization.  The  format  of  this
              file  is  described above.  This file should be writable only by
              root/the owner and should be world-readable.


       /etc/ssh/sshd_config
              Contains configuration data for sshd.  The file format and  con-
              figuration options are described in sshd_config(4).


       /etc/ssh/sshrc
              Similar to ~/.ssh/rc, it can be used to specify machine-specific
              login-time  initializations  globally.   This  file  should   be
              writable only by root, and should be world-readable.


       /var/empty
              chroot(2)  directory used by sshd 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.


       /var/run/sshd.pid
              Contains the process ID of the sshd  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-read-
              able.

SECURITY
       sshd uses pam(3PAM) for password and  keyboard-interactive  methods  as
       well  as  for  account management, session management, and the password
       management for all authentication methods.

       Each SSHv2 userauth type has its own PAM service name:

       -----------------------------------------------
       | SSHv2 Userauth       | PAM Service Name     |
       -----------------------------------------------
       | none                 | sshd-none            |
       -----------------------------------------------
       | password             | sshd-password        |
       -----------------------------------------------
       | keyboard-interactive | sshd-kbdint          |
       -----------------------------------------------
       | pubkey               | sshd-pubkey          |
       -----------------------------------------------
       | hostbased            | sshd-hostbased       |
       -----------------------------------------------
       | gssapi-with-mic      | sshd-gssapi          |
       -----------------------------------------------


ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | network/openssh  |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+
SEE ALSO
       scp(1), sftp(1), ssh(1), ssh-add(1), ssh-agent(1), ssh-keygen(1),  ssh-
       keyscan(1),   chroot(2),   hosts_access(5),  login.conf(5),  moduli(4),
       sshd_config(4), inetd(1M), sftp-server(1M)

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 contrib-
       uted support for privilege separation.

CAVEATS
       System  security  is  not improved unless rshd, rlogind, and rexecd are
       disabled  (thus  completely  disabling  rlogin()  and  rsh()  into  the
       machine).



NOTES
       This     software     was    built    from    source    available    at
       https://java.net/projects/solaris-userland.   The  original   community
       source   was  downloaded  from   http://mirror.team-cymru.org/pub/Open-
       BSD/OpenSSH/portable/openssh-6.5p1.tar.gz

       Further information about this software can be found on the open source
       community website at http://www.openssh.org/.



                               December 7 2013                        SSHD(1M)