4 You will need working installations of Zlib and libcrypto (LibreSSL /
7 Zlib 1.1.4 or 1.2.1.2 or greater (ealier 1.2.x versions have problems):
8 http://www.gzip.org/zlib/
10 libcrypto (LibreSSL or OpenSSL >= 0.9.8f)
11 LibreSSL http://www.libressl.org/ ; or
12 OpenSSL http://www.openssl.org/
14 LibreSSL/OpenSSL should be compiled as a position-independent library
15 (i.e. with -fPIC) otherwise OpenSSH will not be able to link with it.
16 If you must use a non-position-independent libcrypto, then you may need
17 to configure OpenSSH --without-pie.
19 The remaining items are optional.
21 NB. If you operating system supports /dev/random, you should configure
22 libcrypto (LibreSSL/OpenSSL) to use it. OpenSSH relies on libcrypto's
23 direct support of /dev/random, or failing that, either prngd or egd
27 If your system lacks kernel-based random collection, the use of Lutz
28 Jaenicke's PRNGd is recommended.
30 http://prngd.sourceforge.net/
34 If the kernel lacks /dev/random the Entropy Gathering Daemon (EGD) is
35 supported only if libcrypto supports it.
37 http://egd.sourceforge.net/
41 OpenSSH can utilise Pluggable Authentication Modules (PAM) if your
42 system supports it. PAM is standard most Linux distributions, Solaris,
43 HP-UX 11, AIX >= 5.2, FreeBSD and NetBSD.
45 Information about the various PAM implementations are available:
47 Solaris PAM: http://www.sun.com/software/solaris/pam/
48 Linux PAM: http://www.kernel.org/pub/linux/libs/pam/
49 OpenPAM: http://www.openpam.org/
51 If you wish to build the GNOME passphrase requester, you will need the GNOME
52 libraries and headers.
57 Alternatively, Jim Knoble <jmknoble@pobox.com> has written an excellent X11
58 passphrase requester. This is maintained separately at:
60 http://www.jmknoble.net/software/x11-ssh-askpass/
64 If you wish to use the TCP wrappers functionality you will need at least
65 tcpd.h and libwrap.a, either in the standard include and library paths,
66 or in the directory specified by --with-tcp-wrappers. Version 7.6 is
69 http://ftp.porcupine.org/pub/security/index.html
73 If you wish to use --with-skey then you will need the library below
74 installed. No other S/Key library is currently known to be supported.
76 http://www.sparc.spb.su/solaris/skey/
80 sftp supports command-line editing via NetBSD's libedit. If your platform
81 has it available natively you can use that, alternatively you might try
82 these multi-platform ports:
84 http://www.thrysoee.dk/editline/
85 http://sourceforge.net/projects/libedit/
89 LDNS is a DNS BSD-licensed resolver library which supports DNSSEC.
91 http://nlnetlabs.nl/projects/ldns/
95 If you modify configure.ac or configure doesn't exist (eg if you checked
96 the code out of CVS yourself) then you will need autoconf-2.68 to rebuild
97 the automatically generated files by running "autoreconf". Earlier
98 versions may also work but this is not guaranteed.
100 http://www.gnu.org/software/autoconf/
102 Basic Security Module (BSM):
104 Native BSM support is know to exist in Solaris from at least 2.5.1,
105 FreeBSD 6.1 and OS X. Alternatively, you may use the OpenBSM
106 implementation (http://www.openbsm.org).
109 2. Building / Installation
110 --------------------------
112 To install OpenSSH with default options:
118 This will install the OpenSSH binaries in /usr/local/bin, configuration files
119 in /usr/local/etc, the server in /usr/local/sbin, etc. To specify a different
120 installation prefix, use the --prefix option to configure:
122 ./configure --prefix=/opt
126 Will install OpenSSH in /opt/{bin,etc,lib,sbin}. You can also override
127 specific paths, for example:
129 ./configure --prefix=/opt --sysconfdir=/etc/ssh
133 This will install the binaries in /opt/{bin,lib,sbin}, but will place the
134 configuration files in /etc/ssh.
136 If you are using Privilege Separation (which is enabled by default)
137 then you will also need to create the user, group and directory used by
138 sshd for privilege separation. See README.privsep for details.
140 If you are using PAM, you may need to manually install a PAM control
141 file as "/etc/pam.d/sshd" (or wherever your system prefers to keep
142 them). Note that the service name used to start PAM is __progname,
143 which is the basename of the path of your sshd (e.g., the service name
144 for /usr/sbin/osshd will be osshd). If you have renamed your sshd
145 executable, your PAM configuration may need to be modified.
147 A generic PAM configuration is included as "contrib/sshd.pam.generic",
148 you may need to edit it before using it on your system. If you are
149 using a recent version of Red Hat Linux, the config file in
150 contrib/redhat/sshd.pam should be more useful. Failure to install a
151 valid PAM file may result in an inability to use password
152 authentication. On HP-UX 11 and Solaris, the standard /etc/pam.conf
153 configuration will work with sshd (sshd will match the other service
156 There are a few other options to the configure script:
158 --with-audit=[module] enable additional auditing via the specified module.
159 Currently, drivers for "debug" (additional info via syslog) and "bsm"
160 (Sun's Basic Security Module) are supported.
162 --with-pam enables PAM support. If PAM support is compiled in, it must
163 also be enabled in sshd_config (refer to the UsePAM directive).
165 --with-prngd-socket=/some/file allows you to enable EGD or PRNGD
166 support and to specify a PRNGd socket. Use this if your Unix lacks
167 /dev/random and you don't want to use OpenSSH's builtin entropy
170 --with-prngd-port=portnum allows you to enable EGD or PRNGD support
171 and to specify a EGD localhost TCP port. Use this if your Unix lacks
172 /dev/random and you don't want to use OpenSSH's builtin entropy
175 --with-lastlog=FILE will specify the location of the lastlog file.
176 ./configure searches a few locations for lastlog, but may not find
177 it if lastlog is installed in a different place.
179 --without-lastlog will disable lastlog support entirely.
181 --with-osfsia, --without-osfsia will enable or disable OSF1's Security
182 Integration Architecture. The default for OSF1 machines is enable.
184 --with-skey=PATH will enable S/Key one time password support. You will
185 need the S/Key libraries and header files installed for this to work.
187 --with-tcp-wrappers will enable TCP Wrappers (/etc/hosts.allow|deny)
190 --with-md5-passwords will enable the use of MD5 passwords. Enable this
191 if your operating system uses MD5 passwords and the system crypt() does
192 not support them directly (see the crypt(3/3c) man page). If enabled, the
193 resulting binary will support both MD5 and traditional crypt passwords.
195 --with-utmpx enables utmpx support. utmpx support is automatic for
198 --without-shadow disables shadow password support.
200 --with-ipaddr-display forces the use of a numeric IP address in the
201 $DISPLAY environment variable. Some broken systems need this.
203 --with-default-path=PATH allows you to specify a default $PATH for sessions
204 started by sshd. This replaces the standard path entirely.
206 --with-pid-dir=PATH specifies the directory in which the sshd.pid file is
209 --with-xauth=PATH specifies the location of the xauth binary
211 --with-ssl-dir=DIR allows you to specify where your Libre/OpenSSL
215 --with-ssl-engine enables Libre/OpenSSL's (hardware) ENGINE support
217 --with-4in6 Check for IPv4 in IPv6 mapped addresses and convert them to
218 real (AF_INET) IPv4 addresses. Works around some quirks on Linux.
220 If you need to pass special options to the compiler or linker, you
221 can specify these as environment variables before running ./configure.
224 CFLAGS="-O -m486" LDFLAGS="-s" LIBS="-lrubbish" LD="/usr/foo/ld" ./configure
229 The runtime configuration files are installed by in ${prefix}/etc or
230 whatever you specified as your --sysconfdir (/usr/local/etc by default).
232 The default configuration should be instantly usable, though you should
233 review it to ensure that it matches your security requirements.
235 To generate a host key, run "make host-key". Alternately you can do so
236 manually using the following commands:
238 ssh-keygen -t rsa1 -f /etc/ssh/ssh_host_key -N ""
239 ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N ""
240 ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key -N ""
242 Replacing /etc/ssh with the correct path to the configuration directory.
243 (${prefix}/etc or whatever you specified with --sysconfdir during
246 If you have configured OpenSSH with EGD support, ensure that EGD is
247 running and has collected some Entropy.
249 For more information on configuration, please refer to the manual pages
250 for sshd, ssh and ssh-agent.
252 4. (Optional) Send survey
253 -------------------------
256 [check the contents of the file "survey" to ensure there's no information
257 that you consider sensitive]
260 This will send configuration information for the currently configured
261 host to a survey address. This will help determine which configurations
262 are actually in use, and what valid combinations of configure options
263 exist. The raw data is available only to the OpenSSH developers, however
264 summary data may be published.
269 If you experience problems compiling, installing or running OpenSSH.
270 Please refer to the "reporting bugs" section of the webpage at
271 http://www.openssh.com/
274 $Id: INSTALL,v 1.91 2014/09/09 02:23:11 dtucker Exp $