INSTALLATION ON THE UNIX PLATFORM --------------------------------- [Installation on DOS (with djgpp), Windows, OpenVMS, MacOS (before MacOS X) and NetWare is described in INSTALL.DJGPP, INSTALL.W32, INSTALL.VMS, INSTALL.MacOS and INSTALL.NW. This document describes installation on operating systems in the Unix family.] To install OpenSSL, you will need: * make * Perl 5 * an ANSI C compiler * a development environment in form of development libraries and C header files * a supported Unix operating system Quick Start ----------- If you want to just get on with it, do: $ ./config $ make $ make test $ make install [If any of these steps fails, see section Installation in Detail below.] This will build and install OpenSSL in the default location, which is (for historical reasons) /usr/local/ssl. If you want to install it anywhere else, run config like this: $ ./config --prefix=/usr/local --openssldir=/usr/local/openssl Configuration Options --------------------- There are several options to ./config (or ./Configure) to customize the build: --prefix=DIR Install in DIR/bin, DIR/lib, DIR/include/openssl. Configuration files used by OpenSSL will be in DIR/ssl or the directory specified by --openssldir. --openssldir=DIR Directory for OpenSSL files. If no prefix is specified, the library files and binaries are also installed there. no-threads Don't try to build with support for multi-threaded applications. threads Build with support for multi-threaded applications. This will usually require additional system-dependent options! See "Note on multi-threading" below. no-zlib Don't try to build with support for zlib compression and decompression. zlib Build with support for zlib compression/decompression. zlib-dynamic Like "zlib", but has OpenSSL load the zlib library dynamically when needed. This is only supported on systems where loading of shared libraries is supported. This is the default choice. no-shared Don't try to create shared libraries. shared In addition to the usual static libraries, create shared libraries on platforms where it's supported. See "Note on shared libraries" below. no-asm Do not use assembler code. 386 Use the 80386 instruction set only (the default x86 code is more efficient, but requires at least a 486). Note: Use compiler flags for any other CPU specific configuration, e.g. "-m32" to build x86 code on an x64 system. no-sse2 Exclude SSE2 code pathes. Normally SSE2 extention is detected at run-time, but the decision whether or not the machine code will be executed is taken solely on CPU capability vector. This means that if you happen to run OS kernel which does not support SSE2 extension on Intel P4 processor, then your application might be exposed to "illegal instruction" exception. There might be a way to enable support in kernel, e.g. FreeBSD kernel can be compiled with CPU_ENABLE_SSE, and there is a way to disengage SSE2 code pathes upon application start-up, but if you aim for wider "audience" running such kernel, consider no-sse2. Both 386 and no-asm options above imply no-sse2. no-<cipher> Build without the specified cipher (bf, cast, des, dh, dsa, hmac, md2, md5, mdc2, rc2, rc4, rc5, rsa, sha). The crypto/<cipher> directory can be removed after running "make depend". -Dxxx, -lxxx, -Lxxx, -fxxx, -mxxx, -Kxxx These system specific options will be passed through to the compiler to allow you to define preprocessor symbols, specify additional libraries, library directories or other compiler options. Installation in Detail ---------------------- 1a. Configure OpenSSL for your operation system automatically: $ ./config [options] This guesses at your operating system (and compiler, if necessary) and configures OpenSSL based on this guess. Run ./config -t to see if it guessed correctly. If you want to use a different compiler, you are cross-compiling for another platform, or the ./config guess was wrong for other reasons, go to step 1b. Otherwise go to step 2. On some systems, you can include debugging information as follows: $ ./config -d [options] 1b. Configure OpenSSL for your operating system manually OpenSSL knows about a range of different operating system, hardware and compiler combinations. To see the ones it knows about, run $ ./Configure Pick a suitable name from the list that matches your system. For most operating systems there is a choice between using "cc" or "gcc". When you have identified your system (and if necessary compiler) use this name as the argument to ./Configure. For example, a "linux-elf" user would run: $ ./Configure linux-elf [options] If your system is not available, you will have to edit the Configure program and add the correct configuration for your system. The generic configurations "cc" or "gcc" should usually work on 32 bit systems. Configure creates the file Makefile.ssl from Makefile.org and defines various macros in crypto/opensslconf.h (generated from crypto/opensslconf.h.in). 2. Build OpenSSL by running: $ make This will build the OpenSSL libraries (libcrypto.a and libssl.a) and the OpenSSL binary ("openssl"). The libraries will be built in the top-level directory, and the binary will be in the "apps" directory. If "make" fails, look at the output. There may be reasons for the failure that aren't problems in OpenSSL itself (like missing standard headers). If it is a problem with OpenSSL itself, please report the problem to <openssl-bugs@openssl.org> (note that your message will be recorded in the request tracker publicly readable via http://www.openssl.org/support/rt.html and will be forwarded to a public mailing list). Include the output of "make report" in your message. Please check out the request tracker. Maybe the bug was already reported or has already been fixed. [If you encounter assembler error messages, try the "no-asm" configuration option as an immediate fix.] Compiling parts of OpenSSL with gcc and others with the system compiler will result in unresolved symbols on some systems. 3. After a successful build, the libraries should be tested. Run: $ make test If a test fails, look at the output. There may be reasons for the failure that isn't a problem in OpenSSL itself (like a missing or malfunctioning bc). If it is a problem with OpenSSL itself, try removing any compiler optimization flags from the CFLAG line in Makefile.ssl and run "make clean; make". Please send a bug report to <openssl-bugs@openssl.org>, including the output of "make report" in order to be added to the request tracker at http://www.openssl.org/support/rt.html. 4. If everything tests ok, install OpenSSL with $ make install This will create the installation directory (if it does not exist) and then the following subdirectories: certs Initially empty, this is the default location for certificate files. man/man1 Manual pages for the 'openssl' command line tool man/man3 Manual pages for the libraries (very incomplete) misc Various scripts. private Initially empty, this is the default location for private key files. If you didn't choose a different installation prefix, the following additional subdirectories will be created: bin Contains the openssl binary and a few other utility programs. include/openssl Contains the header files needed if you want to compile programs with libcrypto or libssl. lib Contains the OpenSSL library files themselves. Package builders who want to configure the library for standard locations, but have the package installed somewhere else so that it can easily be packaged, can use $ make INSTALL_PREFIX=/tmp/package-root install (or specify "--install_prefix=/tmp/package-root" as a configure option). The specified prefix will be prepended to all installation target filenames. NOTE: The header files used to reside directly in the include directory, but have now been moved to include/openssl so that OpenSSL can co-exist with other libraries which use some of the same filenames. This means that applications that use OpenSSL should now use C preprocessor directives of the form #include <openssl/ssl.h> instead of "#include <ssl.h>", which was used with library versions up to OpenSSL 0.9.2b. If you install a new version of OpenSSL over an old library version, you should delete the old header files in the include directory. Compatibility issues: * COMPILING existing applications To compile an application that uses old filenames -- e.g. "#include <ssl.h>" --, it will usually be enough to find the CFLAGS definition in the application's Makefile and add a C option such as -I/usr/local/ssl/include/openssl to it. But don't delete the existing -I option that points to the ..../include directory! Otherwise, OpenSSL header files could not #include each other. * WRITING applications To write an application that is able to handle both the new and the old directory layout, so that it can still be compiled with library versions up to OpenSSL 0.9.2b without bothering the user, you can proceed as follows: - Always use the new filename of OpenSSL header files, e.g. #include <openssl/ssl.h>. - Create a directory "incl" that contains only a symbolic link named "openssl", which points to the "include" directory of OpenSSL. For example, your application's Makefile might contain the following rule, if OPENSSLDIR is a pathname (absolute or relative) of the directory where OpenSSL resides: incl/openssl: -mkdir incl cd $(OPENSSLDIR) # Check whether the directory really exists -ln -s `cd $(OPENSSLDIR); pwd`/include incl/openssl You will have to add "incl/openssl" to the dependencies of those C files that include some OpenSSL header file. - Add "-Iincl" to your CFLAGS. With these additions, the OpenSSL header files will be available under both name variants if an old library version is used: Your application can reach them under names like <openssl/foo.h>, while the header files still are able to #include each other with names of the form <foo.h>. Note on multi-threading ----------------------- For some systems, the OpenSSL Configure script knows what compiler options are needed to generate a library that is suitable for multi-threaded applications. On these systems, support for multi-threading is enabled by default; use the "no-threads" option to disable (this should never be necessary). On other systems, to enable support for multi-threading, you will have to specify at least two options: "threads", and a system-dependent option. (The latter is "-D_REENTRANT" on various systems.) The default in this case, obviously, is not to include support for multi-threading (but you can still use "no-threads" to suppress an annoying warning message from the Configure script.) Note on shared libraries ------------------------ Shared libraries have certain caveats. Binary backward compatibility can't be guaranteed before OpenSSL version 1.0. The only reason to use them would be to conserve memory on systems where several programs are using OpenSSL. For some systems, the OpenSSL Configure script knows what is needed to build shared libraries for libcrypto and libssl. On these systems, the shared libraries are currently not created by default, but giving the option "shared" will get them created. This method supports Makefile targets for shared library creation, like linux-shared. Those targets can currently be used on their own just as well, but this is expected to change in future versions of OpenSSL. Note on random number generation -------------------------------- Availability of cryptographically secure random numbers is required for secret key generation. OpenSSL provides several options to seed the internal PRNG. If not properly seeded, the internal PRNG will refuse to deliver random bytes and a "PRNG not seeded error" will occur. On systems without /dev/urandom (or similar) device, it may be necessary to install additional support software to obtain random seed. Please check out the manual pages for RAND_add(), RAND_bytes(), RAND_egd(), and the FAQ for more information. Note on support for multiple builds ----------------------------------- OpenSSL is usually built in its source tree. Unfortunately, this doesn't support building for multiple platforms from the same source tree very well. It is however possible to build in a separate tree through the use of lots of symbolic links, which should be prepared like this: mkdir -p objtree/"`uname -s`-`uname -r`-`uname -m`" cd objtree/"`uname -s`-`uname -r`-`uname -m`" (cd $OPENSSL_SOURCE; find . -type f) | while read F; do mkdir -p `dirname $F` rm -f $F; ln -s $OPENSSL_SOURCE/$F $F echo $F '->' $OPENSSL_SOURCE/$F done make -f Makefile.org clean OPENSSL_SOURCE is an environment variable that contains the absolute (this is important!) path to the OpenSSL source tree. Also, operations like 'make update' should still be made in the source tree.