2 INSTALLATION ON THE UNIX PLATFORM
3 ---------------------------------
5 [Installation on DOS (with djgpp), Windows, OpenVMS, MacOS (before MacOS X)
6 and NetWare is described in INSTALL.DJGPP, INSTALL.W32, INSTALL.VMS,
7 INSTALL.MacOS and INSTALL.NW.
9 This document describes installation on operating systems in the Unix
12 To install OpenSSL, you will need:
17 * a development environment in form of development libraries and C
19 * a supported Unix operating system
24 If you want to just get on with it, do:
31 [If any of these steps fails, see section Installation in Detail below.]
33 This will build and install OpenSSL in the default location, which is (for
34 historical reasons) /usr/local/ssl. If you want to install it anywhere else,
37 $ ./config --prefix=/usr/local --openssldir=/usr/local/openssl
43 There are several options to ./config (or ./Configure) to customize
46 --prefix=DIR Install in DIR/bin, DIR/lib, DIR/include/openssl.
47 Configuration files used by OpenSSL will be in DIR/ssl
48 or the directory specified by --openssldir.
50 --openssldir=DIR Directory for OpenSSL files. If no prefix is specified,
51 the library files and binaries are also installed there.
53 no-threads Don't try to build with support for multi-threaded
56 threads Build with support for multi-threaded applications.
57 This will usually require additional system-dependent options!
58 See "Note on multi-threading" below.
60 no-zlib Don't try to build with support for zlib compression and
63 zlib Build with support for zlib compression/decompression.
65 zlib-dynamic Like "zlib", but has OpenSSL load the zlib library dynamically
66 when needed. This is only supported on systems where loading
67 of shared libraries is supported. This is the default choice.
69 no-shared Don't try to create shared libraries.
71 shared In addition to the usual static libraries, create shared
72 libraries on platforms where it's supported. See "Note on
73 shared libraries" below.
75 no-asm Do not use assembler code.
77 386 In 32-bit x86 builds, when generating assembly modules,
78 use the 80386 instruction set only (the default x86 code
79 is more efficient, but requires at least a 486). Note:
80 This doesn't affect code generated by compiler, you're
81 likely to complement configuration command line with
82 suitable compiler-specific option.
84 no-sse2 Exclude SSE2 code paths from 32-bit x86 assembly modules.
85 Normally SSE2 extension is detected at run-time, but the
86 decision whether or not the machine code will be executed
87 is taken solely on CPU capability vector. This means that
88 if you happen to run OS kernel which does not support SSE2
89 extension on Intel P4 processor, then your application
90 might be exposed to "illegal instruction" exception.
91 There might be a way to enable support in kernel, e.g.
92 FreeBSD kernel can be compiled with CPU_ENABLE_SSE, and
93 there is a way to disengage SSE2 code paths upon application
94 start-up, but if you aim for wider "audience" running
95 such kernel, consider no-sse2. Both the 386 and
96 no-asm options imply no-sse2.
98 no-<cipher> Build without the specified cipher (bf, cast, des, dh, dsa,
99 hmac, md2, md5, mdc2, rc2, rc4, rc5, rsa, sha).
100 The crypto/<cipher> directory can be removed after running
103 -Dxxx, -lxxx, -Lxxx, -fxxx, -mXXX, -Kxxx These system specific options will
104 be passed through to the compiler to allow you to
105 define preprocessor symbols, specify additional libraries,
106 library directories or other compiler options. It might be
107 worth noting that some compilers generate code specifically
108 for processor the compiler currently executes on. This is
109 not necessarily what you might have in mind, since it might
110 be unsuitable for execution on other, typically older,
111 processor. Consult your compiler documentation.
113 -DHAVE_CRYPTODEV Enable the BSD cryptodev engine even if we are not using
114 BSD. Useful if you are running ocf-linux or something
115 similar. Once enabled you can also enable the use of
116 cryptodev digests, which is usually slower unless you have
117 large amounts data. Use -DUSE_CRYPTODEV_DIGESTS to force
120 Installation in Detail
121 ----------------------
123 1a. Configure OpenSSL for your operation system automatically:
127 This guesses at your operating system (and compiler, if necessary) and
128 configures OpenSSL based on this guess. Run ./config -t to see
129 if it guessed correctly. If you want to use a different compiler, you
130 are cross-compiling for another platform, or the ./config guess was
131 wrong for other reasons, go to step 1b. Otherwise go to step 2.
133 On some systems, you can include debugging information as follows:
135 $ ./config -d [options]
137 1b. Configure OpenSSL for your operating system manually
139 OpenSSL knows about a range of different operating system, hardware and
140 compiler combinations. To see the ones it knows about, run
144 Pick a suitable name from the list that matches your system. For most
145 operating systems there is a choice between using "cc" or "gcc". When
146 you have identified your system (and if necessary compiler) use this name
147 as the argument to ./Configure. For example, a "linux-elf" user would
150 $ ./Configure linux-elf [options]
152 If your system is not available, you will have to edit the Configure
153 program and add the correct configuration for your system. The
154 generic configurations "cc" or "gcc" should usually work on 32 bit
157 Configure creates the file Makefile.ssl from Makefile.org and
158 defines various macros in crypto/opensslconf.h (generated from
159 crypto/opensslconf.h.in).
161 2. Build OpenSSL by running:
165 This will build the OpenSSL libraries (libcrypto.a and libssl.a) and the
166 OpenSSL binary ("openssl"). The libraries will be built in the top-level
167 directory, and the binary will be in the "apps" directory.
169 If the build fails, look at the output. There may be reasons
170 for the failure that aren't problems in OpenSSL itself (like
171 missing standard headers). If you are having problems you can
172 get help by sending an email to the openssl-users email list (see
173 https://www.openssl.org/community/mailinglists.html for details). If
174 it is a bug with OpenSSL itself, please open an issue on GitHub, at
175 https://github.com/openssl/openssl/issues. Please review the existing
176 ones first; maybe the bug was already reported or has already been
179 (If you encounter assembler error messages, try the "no-asm"
180 configuration option as an immediate fix.)
182 Compiling parts of OpenSSL with gcc and others with the system
183 compiler will result in unresolved symbols on some systems.
185 3. After a successful build, the libraries should be tested. Run:
189 If a test fails, look at the output. There may be reasons for
190 the failure that isn't a problem in OpenSSL itself (like a missing
191 or malfunctioning bc). If it is a problem with OpenSSL itself,
192 try removing any compiler optimization flags from the CFLAG line
193 in Makefile.ssl and run "make clean; make". To report a bug please open an
194 issue on GitHub, at https://github.com/openssl/openssl/issues.
196 4. If everything tests ok, install OpenSSL with
200 This will create the installation directory (if it does not exist) and
201 then the following subdirectories:
203 certs Initially empty, this is the default location
204 for certificate files.
205 man/man1 Manual pages for the 'openssl' command line tool
206 man/man3 Manual pages for the libraries (very incomplete)
207 misc Various scripts.
208 private Initially empty, this is the default location
209 for private key files.
211 If you didn't choose a different installation prefix, the
212 following additional subdirectories will be created:
214 bin Contains the openssl binary and a few other
216 include/openssl Contains the header files needed if you want to
217 compile programs with libcrypto or libssl.
218 lib Contains the OpenSSL library files themselves.
220 Use "make install_sw" to install the software without documentation,
221 and "install_docs_html" to install HTML renditions of the manual
224 Package builders who want to configure the library for standard
225 locations, but have the package installed somewhere else so that
226 it can easily be packaged, can use
228 $ make INSTALL_PREFIX=/tmp/package-root install
230 (or specify "--install_prefix=/tmp/package-root" as a configure
231 option). The specified prefix will be prepended to all
232 installation target filenames.
235 NOTE: The header files used to reside directly in the include
236 directory, but have now been moved to include/openssl so that
237 OpenSSL can co-exist with other libraries which use some of the
238 same filenames. This means that applications that use OpenSSL
239 should now use C preprocessor directives of the form
241 #include <openssl/ssl.h>
243 instead of "#include <ssl.h>", which was used with library versions
244 up to OpenSSL 0.9.2b.
246 If you install a new version of OpenSSL over an old library version,
247 you should delete the old header files in the include directory.
249 Compatibility issues:
251 * COMPILING existing applications
253 To compile an application that uses old filenames -- e.g.
254 "#include <ssl.h>" --, it will usually be enough to find
255 the CFLAGS definition in the application's Makefile and
256 add a C option such as
258 -I/usr/local/ssl/include/openssl
262 But don't delete the existing -I option that points to
263 the ..../include directory! Otherwise, OpenSSL header files
264 could not #include each other.
266 * WRITING applications
268 To write an application that is able to handle both the new
269 and the old directory layout, so that it can still be compiled
270 with library versions up to OpenSSL 0.9.2b without bothering
271 the user, you can proceed as follows:
273 - Always use the new filename of OpenSSL header files,
274 e.g. #include <openssl/ssl.h>.
276 - Create a directory "incl" that contains only a symbolic
277 link named "openssl", which points to the "include" directory
279 For example, your application's Makefile might contain the
280 following rule, if OPENSSLDIR is a pathname (absolute or
281 relative) of the directory where OpenSSL resides:
285 cd $(OPENSSLDIR) # Check whether the directory really exists
286 -ln -s `cd $(OPENSSLDIR); pwd`/include incl/openssl
288 You will have to add "incl/openssl" to the dependencies
289 of those C files that include some OpenSSL header file.
291 - Add "-Iincl" to your CFLAGS.
293 With these additions, the OpenSSL header files will be available
294 under both name variants if an old library version is used:
295 Your application can reach them under names like <openssl/foo.h>,
296 while the header files still are able to #include each other
297 with names of the form <foo.h>.
300 Note on multi-threading
301 -----------------------
303 For some systems, the OpenSSL Configure script knows what compiler options
304 are needed to generate a library that is suitable for multi-threaded
305 applications. On these systems, support for multi-threading is enabled
306 by default; use the "no-threads" option to disable (this should never be
309 On other systems, to enable support for multi-threading, you will have
310 to specify at least two options: "threads", and a system-dependent option.
311 (The latter is "-D_REENTRANT" on various systems.) The default in this
312 case, obviously, is not to include support for multi-threading (but
313 you can still use "no-threads" to suppress an annoying warning message
314 from the Configure script.)
317 Note on shared libraries
318 ------------------------
320 Shared libraries have certain caveats. Binary backward compatibility
321 can't be guaranteed before OpenSSL version 1.0. The only reason to
322 use them would be to conserve memory on systems where several programs
325 For some systems, the OpenSSL Configure script knows what is needed to
326 build shared libraries for libcrypto and libssl. On these systems,
327 the shared libraries are currently not created by default, but giving
328 the option "shared" will get them created. This method supports Makefile
329 targets for shared library creation, like linux-shared. Those targets
330 can currently be used on their own just as well, but this is expected
331 to change in future versions of OpenSSL.
333 Note on random number generation
334 --------------------------------
336 Availability of cryptographically secure random numbers is required for
337 secret key generation. OpenSSL provides several options to seed the
338 internal PRNG. If not properly seeded, the internal PRNG will refuse
339 to deliver random bytes and a "PRNG not seeded error" will occur.
340 On systems without /dev/urandom (or similar) device, it may be necessary
341 to install additional support software to obtain random seed.
342 Please check out the manual pages for RAND_add(), RAND_bytes(), RAND_egd(),
343 and the FAQ for more information.
345 Note on support for multiple builds
346 -----------------------------------
348 OpenSSL is usually built in its source tree. Unfortunately, this doesn't
349 support building for multiple platforms from the same source tree very well.
350 It is however possible to build in a separate tree through the use of lots
351 of symbolic links, which should be prepared like this:
353 mkdir -p objtree/"`uname -s`-`uname -r`-`uname -m`"
354 cd objtree/"`uname -s`-`uname -r`-`uname -m`"
355 (cd $OPENSSL_SOURCE; find . -type f) | while read F; do
356 mkdir -p `dirname $F`
357 rm -f $F; ln -s $OPENSSL_SOURCE/$F $F
358 echo $F '->' $OPENSSL_SOURCE/$F
360 make -f Makefile.org clean
362 OPENSSL_SOURCE is an environment variable that contains the absolute (this
363 is important!) path to the OpenSSL source tree.
365 Also, operations like 'make update' should still be made in the source tree.