4 You will need working installations of Zlib and OpenSSL.
7 http://www.gzip.org/zlib/
9 OpenSSL 0.9.6 or greater:
10 http://www.openssl.org/
12 (OpenSSL 0.9.5a is partially supported, but some ciphers (SSH protocol 1
13 Blowfish) do not work correctly.)
15 OpenSSH can utilise Pluggable Authentication Modules (PAM) if your system
16 supports it. PAM is standard on Redhat and Debian Linux, Solaris and
19 NB. If you operating system supports /dev/random, you should configure
20 OpenSSL to use it. OpenSSH relies on OpenSSL's direct support of
21 /dev/random. If you don't you will have to rely on ssh-rand-helper, which
22 is inferior to a good kernel-based solution.
25 http://www.kernel.org/pub/linux/libs/pam/
27 If you wish to build the GNOME passphrase requester, you will need the GNOME
28 libraries and headers.
33 Alternatively, Jim Knoble <jmknoble@pobox.com> has written an excellent X11
34 passphrase requester. This is maintained separately at:
36 http://www.jmknoble.net/software/x11-ssh-askpass/
40 If your system lacks Kernel based random collection, the use of Lutz
41 Jaenicke's PRNGd is recommended.
43 http://www.aet.tu-cottbus.de/personen/jaenicke/postfix_tls/prngd.html
47 The Entropy Gathering Daemon (EGD) is supported if you have a system which
48 lacks /dev/random and don't want to use OpenSSH's internal entropy collection.
50 http://www.lothar.com/tech/crypto/
54 If you wish to use --with-skey then you will need the above library
55 installed. No other current S/Key library is currently known to be
58 http://www.sparc.spb.su/solaris/skey/
61 sftp now supports command-line editing via NetBSD's libedit. If your
62 platform has it available natively you can use that, alternatively
63 you might try these multi-platform ports:
65 http://www.thrysoee.dk/editline/
66 http://sourceforge.net/projects/libedit/
68 2. Building / Installation
69 --------------------------
71 To install OpenSSH with default options:
77 This will install the OpenSSH binaries in /usr/local/bin, configuration files
78 in /usr/local/etc, the server in /usr/local/sbin, etc. To specify a different
79 installation prefix, use the --prefix option to configure:
81 ./configure --prefix=/opt
85 Will install OpenSSH in /opt/{bin,etc,lib,sbin}. You can also override
86 specific paths, for example:
88 ./configure --prefix=/opt --sysconfdir=/etc/ssh
92 This will install the binaries in /opt/{bin,lib,sbin}, but will place the
93 configuration files in /etc/ssh.
95 If you are using Privilege Separation (which is enabled by default)
96 then you will also need to create the user, group and directory used by
97 sshd for privilege separation. See README.privsep for details.
99 If you are using PAM, you may need to manually install a PAM control
100 file as "/etc/pam.d/sshd" (or wherever your system prefers to keep
101 them). Note that the service name used to start PAM is __progname,
102 which is the basename of the path of your sshd (e.g., the service name
103 for /usr/sbin/osshd will be osshd). If you have renamed your sshd
104 executable, your PAM configuration may need to be modified.
106 A generic PAM configuration is included as "contrib/sshd.pam.generic",
107 you may need to edit it before using it on your system. If you are
108 using a recent version of Red Hat Linux, the config file in
109 contrib/redhat/sshd.pam should be more useful. Failure to install a
110 valid PAM file may result in an inability to use password
111 authentication. On HP-UX 11 and Solaris, the standard /etc/pam.conf
112 configuration will work with sshd (sshd will match the other service
115 There are a few other options to the configure script:
117 --with-pam enables PAM support. If PAM support is compiled in, it must
118 also be enabled in sshd_config (refer to the UsePAM directive).
120 --with-prngd-socket=/some/file allows you to enable EGD or PRNGD
121 support and to specify a PRNGd socket. Use this if your Unix lacks
122 /dev/random and you don't want to use OpenSSH's builtin entropy
125 --with-prngd-port=portnum allows you to enable EGD or PRNGD support
126 and to specify a EGD localhost TCP port. Use this if your Unix lacks
127 /dev/random and you don't want to use OpenSSH's builtin entropy
130 --with-lastlog=FILE will specify the location of the lastlog file.
131 ./configure searches a few locations for lastlog, but may not find
132 it if lastlog is installed in a different place.
134 --without-lastlog will disable lastlog support entirely.
136 --with-osfsia, --without-osfsia will enable or disable OSF1's Security
137 Integration Architecture. The default for OSF1 machines is enable.
139 --with-skey=PATH will enable S/Key one time password support. You will
140 need the S/Key libraries and header files installed for this to work.
142 --with-tcp-wrappers will enable TCP Wrappers (/etc/hosts.allow|deny)
143 support. You will need libwrap.a and tcpd.h installed.
145 --with-md5-passwords will enable the use of MD5 passwords. Enable this
146 if your operating system uses MD5 passwords and the system crypt() does
147 not support them directly (see the crypt(3/3c) man page). If enabled, the
148 resulting binary will support both MD5 and traditional crypt passwords.
150 --with-utmpx enables utmpx support. utmpx support is automatic for
153 --without-shadow disables shadow password support.
155 --with-ipaddr-display forces the use of a numeric IP address in the
156 $DISPLAY environment variable. Some broken systems need this.
158 --with-default-path=PATH allows you to specify a default $PATH for sessions
159 started by sshd. This replaces the standard path entirely.
161 --with-pid-dir=PATH specifies the directory in which the ssh.pid file is
164 --with-xauth=PATH specifies the location of the xauth binary
166 --with-ssl-dir=DIR allows you to specify where your OpenSSL libraries
169 --with-4in6 Check for IPv4 in IPv6 mapped addresses and convert them to
170 real (AF_INET) IPv4 addresses. Works around some quirks on Linux.
173 --with-sectok=DIR allows for OpenSC or sectok smartcard libraries to
174 be used with OpenSSH. See 'README.smartcard' for more details.
176 If you need to pass special options to the compiler or linker, you
177 can specify these as environment variables before running ./configure.
180 CFLAGS="-O -m486" LDFLAGS="-s" LIBS="-lrubbish" LD="/usr/foo/ld" ./configure
185 The runtime configuration files are installed by in ${prefix}/etc or
186 whatever you specified as your --sysconfdir (/usr/local/etc by default).
188 The default configuration should be instantly usable, though you should
189 review it to ensure that it matches your security requirements.
191 To generate a host key, run "make host-key". Alternately you can do so
192 manually using the following commands:
194 ssh-keygen -t rsa1 -f /etc/ssh/ssh_host_key -N ""
195 ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N ""
196 ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key -N ""
198 Replacing /etc/ssh with the correct path to the configuration directory.
199 (${prefix}/etc or whatever you specified with --sysconfdir during
202 If you have configured OpenSSH with EGD support, ensure that EGD is
203 running and has collected some Entropy.
205 For more information on configuration, please refer to the manual pages
206 for sshd, ssh and ssh-agent.
208 4. (Optional) Send survey
209 -------------------------
212 [check the contents and make sure there's no sensitive information]
215 This will send configuration information for the currently configured
216 host to a survey address. This will help determine which configurations
217 are actually in use, and what valid combinations of configure options
218 exist. The raw data is available only to the OpenSSH developers, however
219 summary data may be published.
224 If you experience problems compiling, installing or running OpenSSH.
225 Please refer to the "reporting bugs" section of the webpage at
226 http://www.openssh.com/