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 < 1.1.0)
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. Note that because of API changes,
18 OpenSSL 1.1.x is not currently supported.
20 The remaining items are optional.
22 NB. If you operating system supports /dev/random, you should configure
23 libcrypto (LibreSSL/OpenSSL) to use it. OpenSSH relies on libcrypto's
24 direct support of /dev/random, or failing that, either prngd or egd
28 If your system lacks kernel-based random collection, the use of Lutz
29 Jaenicke's PRNGd is recommended.
31 http://prngd.sourceforge.net/
35 If the kernel lacks /dev/random the Entropy Gathering Daemon (EGD) is
36 supported only if libcrypto supports it.
38 http://egd.sourceforge.net/
42 OpenSSH can utilise Pluggable Authentication Modules (PAM) if your
43 system supports it. PAM is standard most Linux distributions, Solaris,
44 HP-UX 11, AIX >= 5.2, FreeBSD and NetBSD.
46 Information about the various PAM implementations are available:
48 Solaris PAM: http://www.sun.com/software/solaris/pam/
49 Linux PAM: http://www.kernel.org/pub/linux/libs/pam/
50 OpenPAM: http://www.openpam.org/
52 If you wish to build the GNOME passphrase requester, you will need the GNOME
53 libraries and headers.
58 Alternatively, Jim Knoble <jmknoble@pobox.com> has written an excellent X11
59 passphrase requester. This is maintained separately at:
61 http://www.jmknoble.net/software/x11-ssh-askpass/
65 If you wish to use the TCP wrappers functionality you will need at least
66 tcpd.h and libwrap.a, either in the standard include and library paths,
67 or in the directory specified by --with-tcp-wrappers. Version 7.6 is
70 http://ftp.porcupine.org/pub/security/index.html
74 If you wish to use --with-skey then you will need the library below
75 installed. No other S/Key library is currently known to be supported.
77 http://www.sparc.spb.su/solaris/skey/
81 sftp supports command-line editing via NetBSD's libedit. If your platform
82 has it available natively you can use that, alternatively you might try
83 these multi-platform ports:
85 http://www.thrysoee.dk/editline/
86 http://sourceforge.net/projects/libedit/
90 LDNS is a DNS BSD-licensed resolver library which supports DNSSEC.
92 http://nlnetlabs.nl/projects/ldns/
96 If you modify configure.ac or configure doesn't exist (eg if you checked
97 the code out of CVS yourself) then you will need autoconf-2.68 to rebuild
98 the automatically generated files by running "autoreconf". Earlier
99 versions may also work but this is not guaranteed.
101 http://www.gnu.org/software/autoconf/
103 Basic Security Module (BSM):
105 Native BSM support is know to exist in Solaris from at least 2.5.1,
106 FreeBSD 6.1 and OS X. Alternatively, you may use the OpenBSM
107 implementation (http://www.openbsm.org).
110 2. Building / Installation
111 --------------------------
113 To install OpenSSH with default options:
119 This will install the OpenSSH binaries in /usr/local/bin, configuration files
120 in /usr/local/etc, the server in /usr/local/sbin, etc. To specify a different
121 installation prefix, use the --prefix option to configure:
123 ./configure --prefix=/opt
127 Will install OpenSSH in /opt/{bin,etc,lib,sbin}. You can also override
128 specific paths, for example:
130 ./configure --prefix=/opt --sysconfdir=/etc/ssh
134 This will install the binaries in /opt/{bin,lib,sbin}, but will place the
135 configuration files in /etc/ssh.
137 If you are using Privilege Separation (which is enabled by default)
138 then you will also need to create the user, group and directory used by
139 sshd for privilege separation. See README.privsep for details.
141 If you are using PAM, you may need to manually install a PAM control
142 file as "/etc/pam.d/sshd" (or wherever your system prefers to keep
143 them). Note that the service name used to start PAM is __progname,
144 which is the basename of the path of your sshd (e.g., the service name
145 for /usr/sbin/osshd will be osshd). If you have renamed your sshd
146 executable, your PAM configuration may need to be modified.
148 A generic PAM configuration is included as "contrib/sshd.pam.generic",
149 you may need to edit it before using it on your system. If you are
150 using a recent version of Red Hat Linux, the config file in
151 contrib/redhat/sshd.pam should be more useful. Failure to install a
152 valid PAM file may result in an inability to use password
153 authentication. On HP-UX 11 and Solaris, the standard /etc/pam.conf
154 configuration will work with sshd (sshd will match the other service
157 There are a few other options to the configure script:
159 --with-audit=[module] enable additional auditing via the specified module.
160 Currently, drivers for "debug" (additional info via syslog) and "bsm"
161 (Sun's Basic Security Module) are supported.
163 --with-pam enables PAM support. If PAM support is compiled in, it must
164 also be enabled in sshd_config (refer to the UsePAM directive).
166 --with-prngd-socket=/some/file allows you to enable EGD or PRNGD
167 support and to specify a PRNGd socket. Use this if your Unix lacks
168 /dev/random and you don't want to use OpenSSH's builtin entropy
171 --with-prngd-port=portnum allows you to enable EGD or PRNGD support
172 and to specify a EGD localhost TCP port. Use this if your Unix lacks
173 /dev/random and you don't want to use OpenSSH's builtin entropy
176 --with-lastlog=FILE will specify the location of the lastlog file.
177 ./configure searches a few locations for lastlog, but may not find
178 it if lastlog is installed in a different place.
180 --without-lastlog will disable lastlog support entirely.
182 --with-osfsia, --without-osfsia will enable or disable OSF1's Security
183 Integration Architecture. The default for OSF1 machines is enable.
185 --with-skey=PATH will enable S/Key one time password support. You will
186 need the S/Key libraries and header files installed for this to work.
188 --with-tcp-wrappers will enable TCP Wrappers (/etc/hosts.allow|deny)
191 --with-md5-passwords will enable the use of MD5 passwords. Enable this
192 if your operating system uses MD5 passwords and the system crypt() does
193 not support them directly (see the crypt(3/3c) man page). If enabled, the
194 resulting binary will support both MD5 and traditional crypt passwords.
196 --with-utmpx enables utmpx support. utmpx support is automatic for
199 --without-shadow disables shadow password support.
201 --with-ipaddr-display forces the use of a numeric IP address in the
202 $DISPLAY environment variable. Some broken systems need this.
204 --with-default-path=PATH allows you to specify a default $PATH for sessions
205 started by sshd. This replaces the standard path entirely.
207 --with-pid-dir=PATH specifies the directory in which the sshd.pid file is
210 --with-xauth=PATH specifies the location of the xauth binary
212 --with-ssl-dir=DIR allows you to specify where your Libre/OpenSSL
216 --with-ssl-engine enables Libre/OpenSSL's (hardware) ENGINE support
218 --with-4in6 Check for IPv4 in IPv6 mapped addresses and convert them to
219 real (AF_INET) IPv4 addresses. Works around some quirks on Linux.
221 If you need to pass special options to the compiler or linker, you
222 can specify these as environment variables before running ./configure.
225 CFLAGS="-O -m486" LDFLAGS="-s" LIBS="-lrubbish" LD="/usr/foo/ld" ./configure
230 The runtime configuration files are installed by in ${prefix}/etc or
231 whatever you specified as your --sysconfdir (/usr/local/etc by default).
233 The default configuration should be instantly usable, though you should
234 review it to ensure that it matches your security requirements.
236 To generate a host key, run "make host-key". Alternately you can do so
237 manually using the following commands:
239 ssh-keygen -t rsa1 -f /etc/ssh/ssh_host_key -N ""
240 ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N ""
241 ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key -N ""
243 Replacing /etc/ssh with the correct path to the configuration directory.
244 (${prefix}/etc or whatever you specified with --sysconfdir during
247 If you have configured OpenSSH with EGD support, ensure that EGD is
248 running and has collected some Entropy.
250 For more information on configuration, please refer to the manual pages
251 for sshd, ssh and ssh-agent.
253 4. (Optional) Send survey
254 -------------------------
257 [check the contents of the file "survey" to ensure there's no information
258 that you consider sensitive]
261 This will send configuration information for the currently configured
262 host to a survey address. This will help determine which configurations
263 are actually in use, and what valid combinations of configure options
264 exist. The raw data is available only to the OpenSSH developers, however
265 summary data may be published.
270 If you experience problems compiling, installing or running OpenSSH.
271 Please refer to the "reporting bugs" section of the webpage at
272 http://www.openssh.com/
275 $Id: INSTALL,v 1.91 2014/09/09 02:23:11 dtucker Exp $