4 This document describes installation on all supported operating
5 systems (the Unix/Linux family, including macOS), OpenVMS,
11 - [Prerequisites](#prerequisites)
12 - [Notational Conventions](#notational-conventions)
13 - [Quick Installation Guide](#quick-installation-guide)
14 - [Building OpenSSL](#building-openssl)
15 - [Installing OpenSSL](#installing-openssl)
16 - [Configuration Options](#configuration-options)
17 - [API Level](#api-level)
18 - [Cross Compile Prefix](#cross-compile-prefix)
19 - [Build Type](#build-type)
20 - [Directories](#directories)
21 - [Compiler Warnings](#compiler-warnings)
22 - [ZLib Flags](#zlib-flags)
23 - [Seeding the Random Generator](#seeding-the-random-generator)
24 - [Enable and Disable Features](#enable-and-disable-features)
25 - [Displaying configuration data](#displaying-configuration-data)
26 - [Installation Steps in Detail](#installation-steps-in-detail)
27 - [Configure](#configure-openssl)
28 - [Build](#build-openssl)
29 - [Test](#test-openssl)
30 - [Install](#install-openssl)
31 - [Advanced Build Options](#advanced-build-options)
32 - [Environment Variables](#environment-variables)
33 - [Makefile Targets](#makefile-targets)
34 - [Running Selected Tests](#running-selected-tests)
35 - [Troubleshooting](#troubleshooting)
36 - [Configuration Problems](#configuration-problems)
37 - [Build Failures](#build-failures)
38 - [Test Failures](#test-failures)
40 - [Notes on multi-threading](#notes-on-multi-threading)
41 - [Notes on shared libraries](#notes-on-shared-libraries)
42 - [Notes on random number generation](#notes-on-random-number-generation)
47 To install OpenSSL, you will need:
49 * A make implementation
50 * Perl 5 with core modules (please read [NOTES.PERL](NOTES.PERL))
51 * The Perl module Text::Template (please read [NOTES.PERL](NOTES.PERL))
53 * a development environment in the form of development libraries and C
55 * a supported operating system
57 For additional platform specific requirements, solutions to specific
58 issues and other details, please read one of these:
60 * [NOTES.UNIX](NOTES.UNIX) - notes for Unix like systems
61 * [NOTES.VMS](NOTES.VMS) - notes related to OpenVMS
62 * [NOTES.WIN](NOTES.WIN) - notes related to the Windows platform
63 * [NOTES.DJGPP](NOTES.DJGPP) - building for DOS with DJGPP
64 * [NOTES.ANDROID](NOTES.ANDROID) - building for Android platforms (using NDK)
65 * [NOTES.VALGRIND](NOTES.VALGRIND) - testing with Valgrind
66 * [NOTES.PERL](NOTES.PERL) - some notes on Perl
68 Notational conventions
69 ======================
71 Throughout this document, we use the following conventions.
76 Any line starting with a dollar sign is a command line.
80 The dollar sign indicates the shell prompt and is not to be entered as
86 Several words in curly braces separated by pipe characters indicate a
87 **mandatory choice**, to be replaced with one of the given words.
90 $ echo { WORD1 | WORD2 | WORD3 }
92 represents one of the following three commands
100 One or several words in square brackets separated by pipe characters
101 denote an **optional choice**. It is similar to the mandatory choice,
102 but it can also be omitted entirely.
106 $ echo [ WORD1 | WORD2 | WORD3 ]
108 represents one of the four commands
121 **Mandatory arguments** are enclosed in double curly braces.
122 A simple example would be
124 $ type {{ filename }}
126 which is to be understood to use the command `type` on some file name
127 determined by the user.
129 **Optional Arguments** are enclosed in double square brackets.
133 Note that the notation assumes spaces around {, }, [, ], {{, }} and
134 [[, ]]. This is to differentiate from OpenVMS directory
135 specifications, which also use [ and ], but without spaces.
137 Quick Installation Guide
138 ========================
140 If you just want to get OpenSSL installed without bothering too much
141 about the details, here is the short version of how to build and install
142 OpenSSL. If any of the following steps fails, please consult the
143 [Installation in Detail](#installation-in-detail) section below.
148 Use the following commands to configure, build and test OpenSSL.
149 The testing is optional, but recommended if you intend to install
150 OpenSSL for production use.
152 ### Unix / Linux / macOS
160 Use the following commands to build OpenSSL:
168 If you are using Visual Studio, open a Developer Command Prompt and
169 and issue the following commands to build OpenSSL.
171 $ perl Configure { VC-WIN32 | VC-WIN64A | VC-WIN64I | VC-CE }
175 As mentioned in the [Choices](#choices) section, you need to pick one
176 of the four Configure targets in the first command.
178 Most likely you will be using the VC-WIN64A target for 64bit Windows
179 binaries (AMD64) or VC-WIN32 for 32bit Windows binaries (X86).
180 The other two options are VC_WIN64I (Intel IA64, Itanium) and
181 VC-CE (Windows CE) are rather uncommon nowadays.
186 The following commands will install OpenSSL to a default system location.
188 **Danger Zone:** even if you are impatient, please read the following two
189 paragraphs carefully before you install OpenSSL.
191 For security reasons the default system location is by default not writable
192 for unprivileged users. So for the final installation step administrative
193 privileges are required. The default system location and the procedure to
194 obtain administrative privileges depends on the operating sytem.
195 It is recommended to compile and test OpenSSL with normal user privileges
196 and use administrative privileges only for the final installation step.
198 On some platforms OpenSSL is preinstalled as part of the Operating System.
199 In this case it is highly recommended not to overwrite the system versions,
200 because other applications or libraries might depend on it.
201 To avoid breaking other applications, install your copy of OpenSSL to a
202 [different location](#installing-to-a-different-location) which is not in
203 the global search path for system libraries.
205 Finally, if you plan on using the FIPS module, you need to read the
206 [Post-installation Notes](#post-installation-notes) further down.
208 ### Unix / Linux / macOS
210 Depending on your distribution, you need to run the following command as
211 root user or prepend `sudo` to the command:
215 By default, OpenSSL will be installed to
219 More precisely, the files will be installed into the subdirectories
226 depending on the file type, as it is custom on Unix-like operating systems.
230 Use the following command to install OpenSSL.
234 By default, OpenSSL will be installed to
236 SYS$COMMON:[OPENSSL-'version'...]
238 where 'version' is the OpenSSL version number with underscores instead
243 If you are using Visual Studio, open the Developer Command Prompt _elevated_
244 and issue the following command.
248 The easiest way to elevate the Command Prompt is to press and hold down
249 the both the `<CTRL>` and `<SHIFT>` key while clicking the menu item in the
252 The default installation location is
254 C:\Program Files\OpenSSL
256 for native binaries, or
258 C:\Program Files (x86)\OpenSSL
260 for 32bit binaries on 64bit Windows (WOW64).
262 #### Installing to a different location
264 To install OpenSSL to a different location (for example into your home
265 directory for testing purposes) run config as shown in the following
270 $ ./config --prefix=/opt/openssl --openssldir=/usr/local/ssl
274 $ @config --prefix=PROGRAM:[INSTALLS] --openssldir=SYS$MANAGER:[OPENSSL]
276 Note: if you do add options to the configuration command, please make sure
277 you've read more than just this Quick Start, such as relevant `NOTES.*` files,
278 the options outline below, as configuration options may change the outcome
279 in otherwise unexpected ways.
281 Configuration Options
282 =====================
284 There are several options to ./config (or ./Configure) to customize
285 the build (note that for Windows, the defaults for `--prefix` and
286 `--openssldir` depend in what configuration is used and what Windows
287 implementation OpenSSL is built on. More notes on this in NOTES.WIN):
294 Build the OpenSSL libraries to support the API for the specified version.
295 If [no-deprecated](#no-deprecated) is also given, don't build with support
296 for deprecated APIs in or below the specified version number. For example,
299 --api=1.1.0 no-deprecated
301 will remove support for all APIs that were deprecated in OpenSSL version
302 1.1.0 or below. This is a rather specialized option for developers.
303 If you just intend to remove all deprecated APIs up to the current version
304 entirely, just specify [no-deprecated](#no-deprecated).
305 If `--api` isn't given, it defaults to the current (minor) OpenSSL version.
310 --cross-compile-prefix=PREFIX
312 The PREFIX to include in front of commands for your toolchain.
314 It is likely to have to end with dash, e.g. a-b-c- would invoke GNU compiler as
315 a-b-c-gcc, etc. Unfortunately cross-compiling is too case-specific to put
316 together one-size-fits-all instructions. You might have to pass more flags or
317 set up environment variables to actually make it work. Android and iOS cases are
318 discussed in corresponding `Configurations/15-*.conf` files. But there are cases
319 when this option alone is sufficient. For example to build the mingw64 target on
320 Linux `--cross-compile-prefix=x86_64-w64-mingw32-` works. Naturally provided
321 that mingw packages are installed. Today Debian and Ubuntu users have option to
322 install a number of prepackaged cross-compilers along with corresponding
323 run-time and development packages for "alien" hardware. To give another example
324 `--cross-compile-prefix=mipsel-linux-gnu-` suffices in such case. Needless to
325 mention that you have to invoke `./Configure`, not `./config`, and pass your target
326 name explicitly. Also, note that `--openssldir` refers to target's file system,
327 not one you are building on.
334 Build OpenSSL with debugging symbols and zero optimization level.
338 Build OpenSSL without debugging symbols. This is the default.
347 The name of the directory under the top of the installation directory tree
348 (see the `--prefix` option) where libraries will be installed. By default
349 this is "lib". Note that on Windows only static libraries (`*.lib`) will
350 be stored in this location. Shared libraries (`*.dll`) will always be
351 installed to the "bin" directory.
357 Directory for OpenSSL configuration files, and also the default certificate
358 and key store. Defaults are:
361 Windows: C:\Program Files\Common Files\SSL
362 OpenVMS: SYS$COMMON:[OPENSSL-COMMON]
364 For 32bit Windows applications on Windows 64bit (WOW64), always replace
365 `C:\Program Files` by `C:\Program Files (x86)`.
371 The top of the installation directory tree. Defaults are:
374 Windows: C:\Program Files\OpenSSL
375 OpenVMS: SYS$COMMON:[OPENSSL-'version']
382 This is a developer flag that switches on various compiler options recommended
383 for OpenSSL development. It only works when using gcc or clang as the compiler.
384 If you are developing a patch for OpenSSL then it is recommended that you use
385 this option where possible.
390 ### with-zlib-include
392 --with-zlib-include=DIR
394 The directory for the location of the zlib include file. This option is only
395 necessary if [enable-zlib](#enable-zlib) is used and the include file is not
396 already on the system include path.
402 **On Unix**: this is the directory containing the zlib library.
403 If not provided the system library path will be used.
405 **On Windows:** this is the filename of the zlib library (with or
406 without a path). This flag must be provided if the
407 [zlib-dynamic](#zlib-dynamic) option is not also used. If zlib-dynamic is used
408 then this flag is optional and defaults to "ZLIB1" if not provided.
410 **On VMS:** this is the filename of the zlib library (with or without a path).
411 This flag is optional and if not provided then "GNV$LIBZSHR", "GNV$LIBZSHR32"
412 or "GNV$LIBZSHR64" is used by default depending on the pointer size chosen.
414 Seeding the Random Generator
415 ----------------------------
417 --with-rand-seed=seed1[,seed2,...]
419 A comma separated list of seeding methods which will be tried by OpenSSL
420 in order to obtain random input (a.k.a "entropy") for seeding its
421 cryptographically secure random number generator (CSPRNG).
422 The current seeding methods are:
426 Use a trusted operating system entropy source.
427 This is the default method if such an entropy source exists.
431 Use the [getrandom(2)][man-getrandom] or equivalent system call.
433 [man-getrandom]: http://man7.org/linux/man-pages/man2/getrandom.2.html
437 Use the first device from the DEVRANDOM list which can be opened to read
438 random bytes. The DEVRANDOM preprocessor constant expands to
440 "/dev/urandom","/dev/random","/dev/srandom"
442 on most unix-ish operating systems.
446 Check for an entropy generating daemon.
450 Use the RDSEED or RDRAND command if provided by the CPU.
454 Use librandom (not implemented yet).
458 Disable automatic seeding. This is the default on some operating systems where
459 no suitable entropy source exists, or no support for it is implemented yet.
461 For more information, see the section [Notes on random number generation][rng]
462 at the end of this document.
464 [rng]: #notes-on-random-number-generation
466 Enable and Disable Features
467 ---------------------------
469 Feature options always come in pairs, an option to enable feature xxxx, and
470 and option to disable it:
472 [ enable-xxxx | no-xxxx ]
474 Whether a feature is enabled or disabled by default, depends on the feature.
475 In the following list, always the non-default variant is documented: if
476 feature xxxx is disabled by default then enable-xxxx is documented and
477 if feature xxxx is enabled by default then no-xxxx is documented.
481 Don't build the AFALG engine.
483 This option will be forced on a platform that does not support AFALG.
487 Build with Kernel TLS support.
489 This option will enable the use of the Kernel TLS data-path, which can improve
490 performance and allow for the use of sendfile and splice system calls on
491 TLS sockets. The Kernel may use TLS accelerators if any are available on the
492 system. This option will be forced off on systems that do not support the
493 Kernel TLS data-path.
497 Build with the Address sanitiser.
499 This is a developer option only. It may not work on all platforms and should
500 never be used in production environments. It will only work when used with
501 gcc or clang and should be used in conjunction with the [no-shared](#no-shared)
506 Do not build support for Automated Cryptographic Validation Protocol (ACVP)
509 This is required for FIPS validation purposes. Certain ACVP tests require
510 access to algorithm internals that are not normally accessible.
511 Additional information related to ACVP can be found at
512 <https://github.com/usnistgov/ACVP>.
516 Do not use assembler code.
518 This should be viewed as debugging/troubleshooting option rather than for
519 production use. On some platforms a small amount of assembler code may still
520 be used even with this option.
524 Do not build support for async operations.
528 Don't automatically load all supported ciphers and digests.
530 Typically OpenSSL will make available all of its supported ciphers and digests.
531 For a statically linked application this may be undesirable if small executable
532 size is an objective. This only affects libcrypto. Ciphers and digests will
533 have to be loaded manually using EVP_add_cipher() and EVP_add_digest() if this
534 option is used. This option will force a non-shared build.
538 Don't automatically load all libcrypto/libssl error strings.
540 Typically OpenSSL will automatically load human readable error strings. For a
541 statically linked application this may be undesirable if small executable size
544 ### no-autoload-config
546 Don't automatically load the default openssl.cnf file.
548 Typically OpenSSL will automatically load a system config file which configures
551 ### enable-buildtest-c++
553 While testing, generate C++ buildtest files that simply check that the public
554 OpenSSL header files are usable standalone with C++.
556 Enabling this option demands extra care. For any compiler flag given directly
557 as configuration option, you must ensure that it's valid for both the C and
558 the C++ compiler. If not, the C++ build test will most likely break. As an
559 alternative, you can use the language specific variables, CFLAGS and CXXFLAGS.
563 Don't build the CAPI engine.
565 This option will be forced if on a platform that does not support CAPI.
569 Don't build support for Certificate Management Protocol (CMP).
573 Don't build support for Cryptographic Message Syntax (CMS).
577 Don't build support for SSL/TLS compression.
579 If this option is enabled (the default), then compression will only work if
580 the zlib or zlib-dynamic options are also chosen.
582 ### enable-crypto-mdebug
584 This now only enables the failed-malloc feature.
586 ### enable-crypto-mdebug-backtrace
588 This is a no-op; the project uses the compiler's address/leak sanitizer instead.
592 Don't build support for Certificate Transparency (CT).
596 Don't build with support for deprecated APIs up until and including the version
597 given with `--api` (or the current version, if `--api` wasn't specified).
601 Don't build support for datagram based BIOs.
603 Selecting this option will also force the disabling of DTLS.
607 Don't build support for loading Dynamic Shared Objects (DSO)
609 ### enable-devcryptoeng
611 Build the `/dev/crypto` engine.
613 This option is automatically selected on the BSD platform, in which case it can
614 be disabled with no-devcryptoeng.
616 ### no-dynamic-engine
618 Don't build the dynamically loaded engines.
620 This only has an effect in a shared build.
624 Don't build support for Elliptic Curves.
628 Don't build support for binary Elliptic Curves
630 ### enable-ec_nistp_64_gcc_128
632 Enable support for optimised implementations of some commonly used NIST
635 This option is only supported on platforms:
637 - with little-endian storage of non-byte types
638 - that tolerate misaligned memory references
639 - where the compiler:
640 - supports the non-standard type `__uint128_t`
641 - defines the built-in macro `__SIZEOF_INT128__`
645 Build support for gathering entropy from the Entropy Gathering Daemon (EGD).
649 Don't build support for loading engines.
653 Don't compile in any error strings.
655 ### enable-external-tests
657 Enable building of integration with external test suites.
659 This is a developer option and may not work on all platforms. The following
660 external test suites are currently supported:
662 - BoringSSL test suite
663 - Python PYCA/Cryptography test suite
666 See the file [test/README.external]/(test/README.external) for further details.
670 Don't compile in filename and line number information (e.g. for errors and
675 Don't compile the FIPS provider
677 ### enable-fuzz-libfuzzer, enable-fuzz-afl
679 Build with support for fuzzing using either libfuzzer or AFL.
681 These are developer options only. They may not work on all platforms and
682 should never be used in production environments.
684 See the file [fuzz/README.md](fuzz/README.md) for further details.
688 Don't build support for GOST based ciphersuites.
690 Note that if this feature is enabled then GOST ciphersuites are only available
691 if the GOST algorithms are also available through loading an externally supplied
696 Don't build the legacy provider.
698 Disabling this also disables the legacy algorithms: MD2 (already disabled by default).
702 Don't generate dependencies.
706 Don't build any dynamically loadable engines.
708 This also implies 'no-dynamic-engine'.
712 Don't build support for writing multiple records in one go in libssl
714 Note: this is a different capability to the pipelining functionality.
718 Don't build support for the Next Protocol Negotiation (NPN) TLS extension.
722 Don't build support for Online Certificate Status Protocol (OCSP).
726 Don't build the padlock engine.
730 As synonyme for no-padlockeng. Deprecated and should not be used.
734 Don't build with support for Position Independent Code.
738 Don't pin the shared libraries.
740 By default OpenSSL will attempt to stay in memory until the process exits.
741 This is so that libcrypto and libssl can be properly cleaned up automatically
742 via an atexit() handler. The handler is registered by libcrypto and cleans
743 up both libraries. On some platforms the atexit() handler will run on unload of
744 libcrypto (if it has been dynamically loaded) rather than at process exit. This
745 option can be used to stop OpenSSL from attempting to stay in memory until the
746 process exits. This could lead to crashes if either libcrypto or libssl have
747 already been unloaded at the point that the atexit handler is invoked, e.g. on a
748 platform which calls atexit() on unload of the library, and libssl is unloaded
749 before libcrypto then a crash is likely to happen. Applications can suppress
750 running of the atexit() handler at run time by using the OPENSSL_INIT_NO_ATEXIT
751 option to OPENSSL_init_crypto(). See the man page for it for further details.
755 Don't use POSIX IO capabilities.
759 Don't build support for Pre-Shared Key based ciphersuites.
763 Don't use hardware RDRAND capabilities.
767 Don't build support for RFC3779, "X.509 Extensions for IP Addresses and
772 Build support for Stream Control Transmission Protocol (SCTP).
776 Do not create shared libraries, only static ones.
778 See [Notes on shared libraries](#notes-on-shared-libraries) below.
782 Don't build support for socket BIOs.
786 Don't build support for Secure Remote Password (SRP) protocol or
787 SRP based ciphersuites.
791 Don't build Secure Real-Time Transport Protocol (SRTP) support.
795 Exclude SSE2 code paths from 32-bit x86 assembly modules.
797 Normally SSE2 extension is detected at run-time, but the decision whether or not
798 the machine code will be executed is taken solely on CPU capability vector. This
799 means that if you happen to run OS kernel which does not support SSE2 extension
800 on Intel P4 processor, then your application might be exposed to "illegal
801 instruction" exception. There might be a way to enable support in kernel, e.g.
802 FreeBSD kernel can be compiled with CPU_ENABLE_SSE, and there is a way to
803 disengage SSE2 code paths upon application start-up, but if you aim for wider
804 "audience" running such kernel, consider no-sse2. Both the 386 and no-asm
805 options imply no-sse2.
809 Build with the SSL Trace capabilities.
811 This adds the "-trace" option to s_client and s_server.
815 Don't build the statically linked engines.
817 This only has an impact when not built "shared".
821 Don't use anything from the C header file "stdio.h" that makes use of the "FILE"
822 type. Only libcrypto and libssl can be built in this way. Using this option will
823 suppress building the command line applications. Additionally, since the OpenSSL
824 tests also use the command line applications, the tests will also be skipped.
828 Don't build test programs or run any tests.
832 Don't build with support for multi-threaded applications.
836 Build with support for multi-threaded applications. Most platforms will enable
837 this by default. However if on a platform where this is not the case then this
838 will usually require additional system-dependent options!
840 See [Notes on multi-threading](#notes-on-multi-threading) below.
844 Build with support for the integrated tracing api.
846 See manual pages OSSL_trace_set_channel(3) and OSSL_trace_enabled(3) for details.
850 Don't build Time Stamping (TS) Authority support.
854 Build with the Undefined Behaviour sanitiser (UBSAN).
856 This is a developer option only. It may not work on all platforms and should
857 never be used in production environments. It will only work when used with gcc
858 or clang and should be used in conjunction with the `-DPEDANTIC` option
859 (or the `--strict-warnings` option).
863 Don't build with the User Interface (UI) console method
865 The User Interface console method enables text based console prompts.
869 Enable additional unit test APIs.
871 This should not typically be used in production deployments.
875 Don't build support for UPLINK interface.
877 ### enable-weak-ssl-ciphers
879 Build support for SSL/TLS ciphers that are considered "weak"
881 Enabling this includes for example the RC4 based ciphersuites.
885 Build with support for zlib compression/decompression.
889 Like the zlib option, but has OpenSSL load the zlib library dynamically
892 This is only supported on systems where loading of shared libraries is supported.
896 In 32-bit x86 builds, use the 80386 instruction set only in assembly modules
898 The default x86 code is more efficient, but requires at least an 486 processor.
899 Note: This doesn't affect compiler generated code, so this option needs to be
900 accompanied by a corresponding compiler-specific option.
904 no-{ssl|ssl3|tls|tls1|tls1_1|tls1_2|tls1_3|dtls|dtls1|dtls1_2}
906 Don't build support for negotiating the specified SSL/TLS protocol.
908 If "no-tls" is selected then all of tls1, tls1_1, tls1_2 and tls1_3 are disabled.
909 Similarly "no-dtls" will disable dtls1 and dtls1_2. The "no-ssl" option is
910 synonymous with "no-ssl3". Note this only affects version negotiation.
911 OpenSSL will still provide the methods for applications to explicitly select
912 the individual protocol versions.
914 ### no-{protocol}-method
916 no-{ssl|ssl3|tls|tls1|tls1_1|tls1_2|tls1_3|dtls|dtls1|dtls1_2}-method
918 Analogous to no-{protocol} but in addition do not build the methods for
919 applications to explicitly select individual protocol versions. Note that there
920 is no "no-tls1_3-method" option because there is no application method for
923 Using individual protocol methods directly is deprecated. Applications should
924 use TLS_method() instead.
926 ### enable-{algorithm}
930 Build with support for the specified algorithm.
934 no-{aria|bf|blake2|camellia|cast|chacha|cmac|
935 des|dh|dsa|ecdh|ecdsa|idea|md4|mdc2|ocb|
936 poly1305|rc2|rc4|rmd160|scrypt|seed|
937 siphash|siv|sm2|sm3|sm4|whirlpool}
939 Build without support for the specified algorithm.
941 The "ripemd" algorithm is deprecated and if used is synonymous with rmd160.
943 ### Compiler-specific options
945 -Dxxx, -Ixxx, -Wp, -lxxx, -Lxxx, -Wl, -rpath, -R, -framework, -static
947 These system specific options will be recognised and passed through to the
948 compiler to allow you to define preprocessor symbols, specify additional
949 libraries, library directories or other compiler options. It might be worth
950 noting that some compilers generate code specifically for processor the
951 compiler currently executes on. This is not necessarily what you might have
952 in mind, since it might be unsuitable for execution on other, typically older,
953 processor. Consult your compiler documentation.
955 Take note of the [Environment Variables](#environment-variables) documentation
956 below and how these flags interact with those variables.
960 Additional options that are not otherwise recognised are passed through as
961 they are to the compiler as well. Unix-style options beginning with a
962 '-' or '+' and Windows-style options beginning with a '/' are recognized.
963 Again, consult your compiler documentation.
965 If the option contains arguments separated by spaces, then the URL-style
966 notation %20 can be used for the space character in order to avoid having
967 to quote the option. For example, -opt%20arg gets expanded to -opt arg.
968 In fact, any ASCII character can be encoded as %xx using its hexadecimal
971 Take note of the [Environment Variables](#environment-variables) documentation
972 below and how these flags interact with those variables.
974 ### Environment Variables
978 Assign the given value to the environment variable VAR for Configure.
980 These work just like normal environment variable assignments, but are supported
981 on all platforms and are confined to the configuration scripts only.
982 These assignments override the corresponding value in the inherited environment,
985 The following variables are used as "make variables" and can be used as an
986 alternative to giving preprocessor, compiler and linker options directly as
987 configuration. The following variables are supported:
989 AR The static library archiver.
990 ARFLAGS Flags for the static library archiver.
991 AS The assembler compiler.
992 ASFLAGS Flags for the assembler compiler.
994 CFLAGS Flags for the C compiler.
995 CXX The C++ compiler.
996 CXXFLAGS Flags for the C++ compiler.
997 CPP The C/C++ preprocessor.
998 CPPFLAGS Flags for the C/C++ preprocessor.
999 CPPDEFINES List of CPP macro definitions, separated
1000 by a platform specific character (':' or
1001 space for Unix, ';' for Windows, ',' for
1002 VMS). This can be used instead of using
1003 -D (or what corresponds to that on your
1004 compiler) in CPPFLAGS.
1005 CPPINCLUDES List of CPP inclusion directories, separated
1006 the same way as for CPPDEFINES. This can
1007 be used instead of -I (or what corresponds
1008 to that on your compiler) in CPPFLAGS.
1009 HASHBANGPERL Perl invocation to be inserted after '#!'
1010 in public perl scripts (only relevant on
1012 LD The program linker (not used on Unix, $(CC)
1014 LDFLAGS Flags for the shared library, DSO and
1016 LDLIBS Extra libraries to use when linking.
1017 Takes the form of a space separated list
1018 of library specifications on Unix and
1019 Windows, and as a comma separated list of
1021 RANLIB The library archive indexer.
1022 RC The Windows resource compiler.
1023 RCFLAGS Flags for the Windows resource compiler.
1024 RM The command to remove files and directories.
1026 These cannot be mixed with compiling/linking flags given on the command line.
1027 In other words, something like this isn't permitted.
1029 ./config -DFOO CPPFLAGS=-DBAR -DCOOKIE
1031 Backward compatibility note:
1033 To be compatible with older configuration scripts, the environment variables
1034 are ignored if compiling/linking flags are given on the command line, except
1037 AR, CC, CXX, CROSS_COMPILE, HASHBANGPERL, PERL, RANLIB, RC, and WINDRES
1039 For example, the following command will not see -DBAR:
1041 CPPFLAGS=-DBAR ./config -DCOOKIE
1043 However, the following will see both set variables:
1045 CC=gcc CROSS_COMPILE=x86_64-w64-mingw32- ./config -DCOOKIE
1047 If CC is set, it is advisable to also set CXX to ensure both the C and C++
1048 compiler are in the same "family". This becomes relevant with
1049 'enable-external-tests' and 'enable-buildtest-c++'.
1056 Reconfigure from earlier data.
1058 This fetches the previous command line options and environment from data saved
1059 in "configdata.pm" and runs the configuration process again, using these
1060 options and environment. Note: NO other option is permitted together with
1061 "reconf". This means that you also MUST use "./Configure" (or what corresponds
1062 to that on non-Unix platforms) directly to invoke this option. Note: The
1063 original configuration saves away values for ALL environment variables that were
1064 used, and if they weren't defined, they are still saved away with information
1065 that they weren't originally defined. This information takes precedence over
1066 environment variables that are defined when reconfiguring.
1068 Displaying configuration data
1069 -----------------------------
1071 The configuration script itself will say very little, and finishes by
1072 creating "configdata.pm". This perl module can be loaded by other scripts
1073 to find all the configuration data, and it can also be used as a script to
1074 display all sorts of configuration data in a human readable form.
1076 For more information, please do:
1078 $ ./configdata.pm --help # Unix
1082 $ perl configdata.pm --help # Windows and VMS
1084 Installation Steps in Detail
1085 ============================
1090 ### Automatic Configuration
1092 On some platform a `config` script is available which attempts to guess
1093 your operating system (and compiler, if necessary) and calls the `Configure`
1094 Perl script with appropriate target based on its guess. Further options can
1095 be supplied to the `config` script, which will be passed on to the `Configure`
1098 #### Unix / Linux / macOS
1100 $ ./config [[ options ]]
1104 $ @config [[ options ]]
1108 Automatic configuration is not available on Windows.
1110 For the remainder of this text, the Unix form will be used in all examples,
1111 please use the appropriate form for your platform.
1117 to see whether your target is guessed correctly. If you want to use a different
1118 compiler, you are cross-compiling for another platform, or the ./config guess
1119 was wrong for other reasons, see the [Manual Configuration](#manual-configuration)
1120 section. Oherwise continue with the [Build OpenSSL](#build-openssl) section below.
1122 On some systems, you can include debugging information as follows:
1124 $ ./config -d [[ options ]]
1126 ### Manual Configuration
1128 OpenSSL knows about a range of different operating system, hardware and
1129 compiler combinations. To see the ones it knows about, run
1131 $ ./Configure # Unix
1135 $ perl Configure # All other platforms
1137 For the remainder of this text, the Unix form will be used in all examples.
1138 Please use the appropriate form for your platform.
1140 Pick a suitable name from the list that matches your system. For most
1141 operating systems there is a choice between using "cc" or "gcc".
1142 When you have identified your system (and if necessary compiler) use this
1143 name as the argument to Configure. For example, a "linux-elf" user would
1146 $ ./Configure linux-elf [[ options ]]
1148 ### Creating your own Configuration
1150 If your system isn't listed, you will have to create a configuration
1151 file named Configurations/{{ something }}.conf and add the correct
1152 configuration for your system. See the available configs as examples
1153 and read Configurations/README and Configurations/README.design for
1156 The generic configurations "cc" or "gcc" should usually work on 32 bit
1159 Configure creates a build file ("Makefile" on Unix, "makefile" on Windows
1160 and "descrip.mms" on OpenVMS) from a suitable template in Configurations,
1161 and defines various macros in include/openssl/configuration.h (generated
1162 from include/openssl/configuration.h.in).
1164 ### Out of Tree Builds
1166 OpenSSL can be configured to build in a build directory separate from the
1167 source code directory. It's done by placing yourself in some other
1168 directory and invoking the configuration commands from there.
1172 $ mkdir /var/tmp/openssl-build
1173 $ cd /var/tmp/openssl-build
1174 $ /PATH/TO/OPENSSL/SOURCE/config [[ options ]]
1178 $ /PATH/TO/OPENSSL/SOURCE/Configure {{ target }} [[ options ]]
1180 #### OpenVMS example
1182 $ set default sys$login:
1183 $ create/dir [.tmp.openssl-build]
1184 $ set default [.tmp.openssl-build]
1185 $ @[PATH.TO.OPENSSL.SOURCE]config [[ options ]]
1189 $ @[PATH.TO.OPENSSL.SOURCE]Configure {{ target }} [[ options ]]
1191 #### Windows example
1194 $ mkdir \temp-openssl
1196 $ perl d:\PATH\TO\OPENSSL\SOURCE\Configure {{ target }} [[ options ]]
1198 Paths can be relative just as well as absolute. Configure will do its best
1199 to translate them to relative paths whenever possible.
1204 Build OpenSSL by running:
1207 $ mms ! (or mmk) OpenVMS
1210 This will build the OpenSSL libraries (libcrypto.a and libssl.a on
1211 Unix, corresponding on other platforms) and the OpenSSL binary
1212 ("openssl"). The libraries will be built in the top-level directory,
1213 and the binary will be in the "apps" subdirectory.
1215 If the build fails, take a look at the [Build Failures](#build-failures)
1216 subsection of the [Troubleshooting](#troubleshooting) section.
1221 After a successful build, and before installing, the libraries should
1225 $ mms test ! OpenVMS
1226 $ nmake test # Windows
1228 **Warning:** you MUST run the tests from an unprivileged account (or disable
1229 your privileges temporarily if your platform allows it).
1231 If some tests fail, take a look at the [Test Failures](#test-failures)
1232 subsection of the [Troubleshooting](#troubleshooting) section.
1237 If everything tests ok, install OpenSSL with
1239 $ make install # Unix
1240 $ mms install ! OpenVMS
1241 $ nmake install # Windows
1243 Note that in order to perform the install step above you need to have
1244 appropriate permissions to write to the installation directory.
1246 The above commands will install all the software components in this
1247 directory tree under PREFIX (the directory given with `--prefix` or
1250 ### Unix / Linux / macOS
1252 bin/ Contains the openssl binary and a few other
1255 Contains the header files needed if you want
1256 to build your own programs that use libcrypto
1258 lib Contains the OpenSSL library files.
1259 lib/engines Contains the OpenSSL dynamically loadable engines.
1261 share/man/man1 Contains the OpenSSL command line man-pages.
1262 share/man/man3 Contains the OpenSSL library calls man-pages.
1263 share/man/man5 Contains the OpenSSL configuration format man-pages.
1264 share/man/man7 Contains the OpenSSL other misc man-pages.
1266 share/doc/openssl/html/man1
1267 share/doc/openssl/html/man3
1268 share/doc/openssl/html/man5
1269 share/doc/openssl/html/man7
1270 Contains the HTML rendition of the man-pages.
1274 'arch' is replaced with the architecture name, "Alpha" or "ia64",
1275 'sover' is replaced with the shared library version (0101 for 1.1), and
1276 'pz' is replaced with the pointer size OpenSSL was built with:
1278 [.EXE.'arch'] Contains the openssl binary.
1279 [.EXE] Contains a few utility scripts.
1281 Contains the header files needed if you want
1282 to build your own programs that use libcrypto
1284 [.LIB.'arch'] Contains the OpenSSL library files.
1285 [.ENGINES'sover''pz'.'arch']
1286 Contains the OpenSSL dynamically loadable engines.
1287 [.SYS$STARTUP] Contains startup, login and shutdown scripts.
1288 These define appropriate logical names and
1290 [.SYSTEST] Contains the installation verification procedure.
1291 [.HTML] Contains the HTML rendition of the manual pages.
1293 ### Additional Directories
1295 Additionally, install will add the following directories under
1296 OPENSSLDIR (the directory given with `--openssldir` or its default)
1297 for you convenience:
1299 certs Initially empty, this is the default location
1300 for certificate files.
1301 private Initially empty, this is the default location
1302 for private key files.
1303 misc Various scripts.
1305 The installation directory should be appropriately protected to ensure
1306 unprivileged users cannot make changes to OpenSSL binaries or files, or
1307 install engines. If you already have a pre-installed version of OpenSSL as
1308 part of your Operating System it is recommended that you do not overwrite
1309 the system version and instead install to somewhere else.
1311 Package builders who want to configure the library for standard locations,
1312 but have the package installed somewhere else so that it can easily be
1315 $ make DESTDIR=/tmp/package-root install # Unix
1316 $ mms/macro="DESTDIR=TMP:[PACKAGE-ROOT]" install ! OpenVMS
1318 The specified destination directory will be prepended to all installation
1321 Compatibility issues with previous OpenSSL versions
1322 ---------------------------------------------------
1324 ### COMPILING existing applications
1326 Starting with version 1.1.0, OpenSSL hides a number of structures that were
1327 previously open. This includes all internal libssl structures and a number
1328 of EVP types. Accessor functions have been added to allow controlled access
1329 to the structures' data.
1331 This means that some software needs to be rewritten to adapt to the new ways
1332 of doing things. This often amounts to allocating an instance of a structure
1333 explicitly where you could previously allocate them on the stack as automatic
1334 variables, and using the provided accessor functions where you would previously
1335 access a structure's field directly.
1337 Some APIs have changed as well. However, older APIs have been preserved when
1340 Post-installation Notes
1341 -----------------------
1343 With the default OpenSSL installation comes a FIPS provider module, which
1344 needs some post-installation attention, without which it will not be usable.
1345 This involves using the following command:
1349 See the openssl-fipsinstall(1) manual for details and examples.
1351 Advanced Build Options
1352 ======================
1354 Environment Variables
1355 ---------------------
1357 A number of environment variables can be used to provide additional control
1358 over the build process. Typically these should be defined prior to running
1359 config or Configure. Not all environment variables are relevant to all
1363 The name of the ar executable to use.
1366 Use a different build file name than the platform default
1367 ("Makefile" on Unix-like platforms, "makefile" on native Windows,
1368 "descrip.mms" on OpenVMS). This requires that there is a
1369 corresponding build file template. See Configurations/README
1370 for further information.
1373 The compiler to use. Configure will attempt to pick a default
1374 compiler for your platform but this choice can be overridden
1375 using this variable. Set it to the compiler executable you wish
1376 to use, e.g. "gcc" or "clang".
1379 This environment variable has the same meaning as for the
1380 "--cross-compile-prefix" Configure flag described above. If both
1381 are set then the Configure flag takes precedence.
1384 The name of the nm executable to use.
1386 OPENSSL_LOCAL_CONFIG_DIR
1387 OpenSSL comes with a database of information about how it
1388 should be built on different platforms as well as build file
1389 templates for those platforms. The database is comprised of
1390 ".conf" files in the Configurations directory. The build
1391 file templates reside there as well as ".tmpl" files. See the
1392 file Configurations/README for further information about the
1393 format of ".conf" files as well as information on the ".tmpl"
1395 In addition to the standard ".conf" and ".tmpl" files, it is
1396 possible to create your own ".conf" and ".tmpl" files and store
1397 them locally, outside the OpenSSL source tree. This environment
1398 variable can be set to the directory where these files are held
1399 and will be considered by Configure before it looks in the
1400 standard directories.
1403 The name of the Perl executable to use when building OpenSSL.
1404 This variable is used in config script only. Configure on the
1405 other hand imposes the interpreter by which it itself was
1406 executed on the whole build procedure.
1409 The command string for the Perl executable to insert in the
1410 #! line of perl scripts that will be publicly installed.
1411 Default: /usr/bin/env perl
1412 Note: the value of this variable is added to the same scripts
1413 on all platforms, but it's only relevant on Unix-like platforms.
1416 The name of the rc executable to use. The default will be as
1417 defined for the target platform in the ".conf" file. If not
1418 defined then "windres" will be used. The WINDRES environment
1419 variable is synonymous to this. If both are defined then RC
1423 The name of the ranlib executable to use.
1431 The Configure script generates a Makefile in a format relevant to the specific
1432 platform. The Makefiles provide a number of targets that can be used. Not all
1433 targets may be available on all platforms. Only the most common targets are
1434 described here. Examine the Makefiles themselves for the full list.
1437 The target to build all the software components and
1441 Build all the software components.
1442 THIS IS THE DEFAULT TARGET.
1445 Build all documentation components.
1448 Remove all build artefacts and return the directory to a "clean"
1452 Rebuild the dependencies in the Makefiles. This is a legacy
1453 option that no longer needs to be used since OpenSSL 1.1.0.
1456 Install all OpenSSL components.
1459 Only install the OpenSSL software components.
1462 Only install the OpenSSL documentation components.
1465 Only install the OpenSSL man pages (Unix only).
1468 Only install the OpenSSL html documentation.
1471 Prints a list of all the self test names.
1474 Build and run the OpenSSL self tests.
1477 Uninstall all OpenSSL components.
1481 Re-run the configuration process, as exactly as the last time
1485 This is a developer option. If you are developing a patch for
1486 OpenSSL you may need to use this if you want to update
1487 automatically generated files; add new error codes or add new
1488 (or change the visibility of) public API functions. (Unix only).
1490 Running Selected Tests
1491 ----------------------
1493 The make variable TESTS supports a versatile set of space separated tokens
1494 with which you can specify a set of tests to be performed. With a "current
1495 set of tests" in mind, initially being empty, here are the possible tokens:
1497 alltests The current set of tests becomes the whole set of available
1498 tests (as listed when you do 'make list-tests' or similar).
1500 xxx Adds the test 'xxx' to the current set of tests.
1502 -xxx Removes 'xxx' from the current set of tests. If this is the
1503 first token in the list, the current set of tests is first
1504 assigned the whole set of available tests, effectively making
1505 this token equivalent to TESTS="alltests -xxx".
1507 nn Adds the test group 'nn' (which is a number) to the current
1510 -nn Removes the test group 'nn' from the current set of tests.
1511 If this is the first token in the list, the current set of
1512 tests is first assigned the whole set of available tests,
1513 effectively making this token equivalent to
1514 TESTS="alltests -xxx".
1516 Also, all tokens except for "alltests" may have wildcards, such as *.
1517 (on Unix and Windows, BSD style wildcards are supported, while on VMS,
1518 it's VMS style wildcards)
1522 Run all tests except for the fuzz tests:
1524 $ make TESTS=-test_fuzz test
1526 or, if you want to be explicit:
1528 $ make TESTS='alltests -test_fuzz' test
1530 Run all tests that have a name starting with "test_ssl" but not those
1531 starting with "test_ssl_":
1533 $ make TESTS='test_ssl* -test_ssl_*' test
1535 Run only test group 10:
1539 Run all tests except the slow group (group 99):
1543 Run all tests in test groups 80 to 99 except for tests in group 90:
1545 $ make TESTS='[89]? -90'
1547 To stochastically verify that the algorithm that produces uniformly distributed
1548 random numbers is operating correctly (with a false positive rate of 0.01%):
1550 $ ./util/wrap.sh test/bntest -stochastic
1555 Configuration Problems
1556 ----------------------
1558 ### Selecting the correct target
1560 The `./config` script tries hard to guess your operating system, but in some
1561 cases it does not succeed. You will see a message like the following:
1564 Operating system: x86-whatever-minix
1565 This system (minix) is not supported. See file INSTALL for details.
1567 Even if the automatic target selection by the `./config` script fails, chances
1568 are that you still might find a suitable target in the Configurations directory,
1569 which you can supply to the `./Configure` command, possibly after some adjustment.
1571 The Configurations directory contains a lot of examples of such targets.
1572 The main configuration file is [10-main.conf][], which contains all targets that
1573 are officially supported by the OpenSSL team. Other configuration files contain
1574 targets contributed by other OpenSSL users. The list of targets can be found in
1575 a Perl list `my %targets = ( ... )`.
1580 inherit_from => [ "base-target" ],
1582 cflags => add("..."),
1584 perlasm_scheme => "...",
1589 If you call `.\Configure` without arguments, it will give you a list of all
1590 known targets. Using `grep`, you can lookup the target definition in the
1591 Configurations directory. For example the "android-x86_64" can be found in
1592 Configurations/15-android.conf.
1594 The directory contains two README files, which explain the general syntax and
1595 design of the configurations files.
1597 - [Configurations/README](Configurations/README)
1598 - [Configurations/README.design](Configurations/README.design)
1600 If you need further help, try to search the [openssl-users][] mailing list
1601 or the [GitHub Issues][] for existing solutions. If you don't find anything,
1602 you can [raise an issue][] to ask a question yourself.
1604 More about our support resources can be found in the [SUPPORT][] file.
1606 ### Configuration Errors
1608 If the `./config` or `./Configure` command fails with an error message,
1609 read the error message carefully and try to figure out whether you made
1610 a mistake (e.g., by providing a wrong option), or whether the script is
1611 working incorrectly. If you think you encountered a bug, please
1612 [raise an issue][] on GitHub to file a bug report.
1614 Along with a short description of the bug, please provide the complete
1615 configure command line and the relevant output including the error message.
1617 Note: To make the output readable, pleace add a 'code fence' (three backquotes
1618 ` ``` ` on a separate line) before and after your output:
1621 $ ./Configure [your arguments...]
1630 If the build fails, look carefully at the output. Try to locate and understand
1631 the error message. It might be that the compiler is already telling you
1632 exactly what you need to do to fix your problem.
1634 There may be reasons for the failure that aren't problems in OpenSSL itself,
1635 for example if the compiler reports missing standard or third party headers.
1637 If the build succeeded previously, but fails after a source or configuration
1638 change, it might be helpful to clean the build tree before attempting another
1639 build. Use this command:
1642 $ mms clean ! (or mmk) OpenVMS
1643 $ nmake clean # Windows
1645 Assembler error messages can sometimes be sidestepped by using the
1646 "no-asm" configuration option.
1648 Compiling parts of OpenSSL with gcc and others with the system compiler will
1649 result in unresolved symbols on some systems.
1651 If you are still having problems, try to search the [openssl-users][] mailing
1652 list or the [GitHub Issues][] for existing solutions. If you think you
1653 encountered an OpenSSL bug, please [raise an issue][] to file a bug report.
1654 Please take the time to review the existing issues first; maybe the bug was
1655 already reported or has already been fixed.
1660 If some tests fail, look at the output. There may be reasons for the failure
1661 that isn't a problem in OpenSSL itself (like a malfunction with Perl).
1662 You may want increased verbosity, that can be accomplished like this:
1664 Verbosity on failure only (make macro VERBOSE_FAILURE or VF):
1666 $ make VF=1 test # Unix
1667 $ mms /macro=(VF=1) test ! OpenVMS
1668 $ nmake VF=1 test # Windows
1670 Full verbosity (make macro VERBOSE or V):
1672 $ make V=1 test # Unix
1673 $ mms /macro=(V=1) test ! OpenVMS
1674 $ nmake V=1 test # Windows
1676 If you want to run just one or a few specific tests, you can use
1677 the make variable TESTS to specify them, like this:
1679 $ make TESTS='test_rsa test_dsa' test # Unix
1680 $ mms/macro="TESTS=test_rsa test_dsa" test ! OpenVMS
1681 $ nmake TESTS='test_rsa test_dsa' test # Windows
1683 And of course, you can combine (Unix example shown):
1685 $ make VF=1 TESTS='test_rsa test_dsa' test
1687 You can find the list of available tests like this:
1689 $ make list-tests # Unix
1690 $ mms list-tests ! OpenVMS
1691 $ nmake list-tests # Windows
1693 Have a look at the manual for the perl module Test::Harness to
1694 see what other HARNESS_* variables there are.
1696 If you find a problem with OpenSSL itself, try removing any
1697 compiler optimization flags from the CFLAGS line in Makefile and
1698 run "make clean; make" or corresponding.
1700 To report a bug please open an issue on GitHub, at
1701 <https://github.com/openssl/openssl/issues>.
1703 For more details on how the make variables TESTS can be used,
1704 see section [Running Selected Tests](#running-selected-tests) below.
1709 Notes on multi-threading
1710 ------------------------
1712 For some systems, the OpenSSL Configure script knows what compiler options
1713 are needed to generate a library that is suitable for multi-threaded
1714 applications. On these systems, support for multi-threading is enabled
1715 by default; use the "no-threads" option to disable (this should never be
1718 On other systems, to enable support for multi-threading, you will have
1719 to specify at least two options: "threads", and a system-dependent option.
1720 (The latter is "-D_REENTRANT" on various systems.) The default in this
1721 case, obviously, is not to include support for multi-threading (but
1722 you can still use "no-threads" to suppress an annoying warning message
1723 from the Configure script.)
1725 OpenSSL provides built-in support for two threading models: pthreads (found on
1726 most UNIX/Linux systems), and Windows threads. No other threading models are
1727 supported. If your platform does not provide pthreads or Windows threads then
1728 you should Configure with the "no-threads" option.
1730 Notes on shared libraries
1731 -------------------------
1733 For most systems the OpenSSL Configure script knows what is needed to
1734 build shared libraries for libcrypto and libssl. On these systems
1735 the shared libraries will be created by default. This can be suppressed and
1736 only static libraries created by using the "no-shared" option. On systems
1737 where OpenSSL does not know how to build shared libraries the "no-shared"
1738 option will be forced and only static libraries will be created.
1740 Shared libraries are named a little differently on different platforms.
1741 One way or another, they all have the major OpenSSL version number as
1742 part of the file name, i.e. for OpenSSL 1.1.x, 1.1 is somehow part of
1745 On most POSIX platforms, shared libraries are named libcrypto.so.1.1
1748 on Cygwin, shared libraries are named cygcrypto-1.1.dll and cygssl-1.1.dll
1749 with import libraries libcrypto.dll.a and libssl.dll.a.
1751 On Windows build with MSVC or using MingW, shared libraries are named
1752 libcrypto-1_1.dll and libssl-1_1.dll for 32-bit Windows, libcrypto-1_1-x64.dll
1753 and libssl-1_1-x64.dll for 64-bit x86_64 Windows, and libcrypto-1_1-ia64.dll
1754 and libssl-1_1-ia64.dll for IA64 Windows. With MSVC, the import libraries
1755 are named libcrypto.lib and libssl.lib, while with MingW, they are named
1756 libcrypto.dll.a and libssl.dll.a.
1758 On VMS, shareable images (VMS speak for shared libraries) are named
1759 ossl$libcrypto0101_shr.exe and ossl$libssl0101_shr.exe. However, when
1760 OpenSSL is specifically built for 32-bit pointers, the shareable images
1761 are named ossl$libcrypto0101_shr32.exe and ossl$libssl0101_shr32.exe
1762 instead, and when built for 64-bit pointers, they are named
1763 ossl$libcrypto0101_shr64.exe and ossl$libssl0101_shr64.exe.
1765 Notes on random number generation
1766 ---------------------------------
1768 Availability of cryptographically secure random numbers is required for
1769 secret key generation. OpenSSL provides several options to seed the
1770 internal CSPRNG. If not properly seeded, the internal CSPRNG will refuse
1771 to deliver random bytes and a "PRNG not seeded error" will occur.
1773 The seeding method can be configured using the `--with-rand-seed` option,
1774 which can be used to specify a comma separated list of seed methods.
1775 However in most cases OpenSSL will choose a suitable default method,
1776 so it is not necessary to explicitly provide this option. Note also
1777 that not all methods are available on all platforms.
1779 I) On operating systems which provide a suitable randomness source (in
1780 form of a system call or system device), OpenSSL will use the optimal
1781 available method to seed the CSPRNG from the operating system's
1782 randomness sources. This corresponds to the option `--with-rand-seed=os`.
1784 II) On systems without such a suitable randomness source, automatic seeding
1785 and reseeding is disabled (--with-rand-seed=none) and it may be necessary
1786 to install additional support software to obtain a random seed and reseed
1787 the CSPRNG manually. Please check out the manual pages for RAND_add(),
1788 RAND_bytes(), RAND_egd(), and the FAQ for more information.
1793 <https://mta.openssl.org/mailman/listinfo/openssl-users>
1799 <https://github.com/openssl/openssl/issues>
1802 <https://github.com/openssl/openssl/issues/new/choose>
1805 Configurations/10-main.conf