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  1. OPENSSL INSTALLATION
  2. --------------------
  3. This document describes installation on all supported operating
  4. systems (the Unix/Linux family (which includes Mac OS/X), OpenVMS,
  5. and Windows).
  6. To install OpenSSL, you will need:
  7. * A make implementation
  8. * Perl 5 with core modules (please read NOTES.PERL)
  9. * The perl module Text::Template (please read NOTES.PERL)
  10. * an ANSI C compiler
  11. * a development environment in the form of development libraries and C
  12. header files
  13. * a supported operating system
  14. For additional platform specific requirements, solutions to specific
  15. issues and other details, please read one of these:
  16. * NOTES.UNIX (any supported Unix like system)
  17. * NOTES.VMS (OpenVMS)
  18. * NOTES.WIN (any supported Windows)
  19. * NOTES.DJGPP (DOS platform with DJGPP)
  20. * NOTES.ANDROID (obviously Android [NDK])
  21. * NOTES.VALGRIND (testing with Valgrind)
  22. Notational conventions in this document
  23. ---------------------------------------
  24. Throughout this document, we use the following conventions in command
  25. examples:
  26. $ command Any line starting with a dollar sign
  27. ($) is a command line.
  28. { word1 | word2 | word3 } This denotes a mandatory choice, to be
  29. replaced with one of the given words.
  30. A simple example would be this:
  31. $ echo { FOO | BAR | COOKIE }
  32. which is to be understood as one of
  33. these:
  34. $ echo FOO
  35. - or -
  36. $ echo BAR
  37. - or -
  38. $ echo COOKIE
  39. [ word1 | word2 | word3 ] Similar to { word1 | word2 | word3 }
  40. except it's optional to give any of
  41. those. In addition to the examples
  42. above, this would also be valid:
  43. $ echo
  44. {{ target }} This denotes a mandatory word or
  45. sequence of words of some sort. A
  46. simple example would be this:
  47. $ type {{ filename }}
  48. which is to be understood to use the
  49. command 'type' on some file name
  50. determined by the user.
  51. [[ options ]] Similar to {{ target }}, but is
  52. optional.
  53. Note that the notation assumes spaces around {, }, [, ], {{, }} and
  54. [[, ]]. This is to differentiate from OpenVMS directory
  55. specifications, which also use [ and ], but without spaces.
  56. Quick Start
  57. -----------
  58. If you want to just get on with it, do:
  59. on Unix (again, this includes Mac OS/X):
  60. $ ./config
  61. $ make
  62. $ make test
  63. $ make install
  64. on OpenVMS:
  65. $ @config
  66. $ mms
  67. $ mms test
  68. $ mms install
  69. on Windows (only pick one of the targets for configuration):
  70. $ perl Configure { VC-WIN32 | VC-WIN64A | VC-WIN64I | VC-CE }
  71. $ nmake
  72. $ nmake test
  73. $ nmake install
  74. If any of these steps fails, see section Installation in Detail below.
  75. This will build and install OpenSSL in the default location, which is:
  76. Unix: normal installation directories under /usr/local
  77. OpenVMS: SYS$COMMON:[OPENSSL-'version'...], where 'version' is the
  78. OpenSSL version number with underscores instead of periods.
  79. Windows: C:\Program Files\OpenSSL or C:\Program Files (x86)\OpenSSL
  80. If you want to install it anywhere else, run config like this:
  81. On Unix:
  82. $ ./config --prefix=/opt/openssl --openssldir=/usr/local/ssl
  83. On OpenVMS:
  84. $ @config --prefix=PROGRAM:[INSTALLS] --openssldir=SYS$MANAGER:[OPENSSL]
  85. (Note: if you do add options to the configuration command, please make sure
  86. you've read more than just this Quick Start, such as relevant NOTES.* files,
  87. the options outline below, as configuration options may change the outcome
  88. in otherwise unexpected ways)
  89. Configuration Options
  90. ---------------------
  91. There are several options to ./config (or ./Configure) to customize
  92. the build (note that for Windows, the defaults for --prefix and
  93. --openssldir depend in what configuration is used and what Windows
  94. implementation OpenSSL is built on. More notes on this in NOTES.WIN):
  95. --api=x.y.z
  96. Don't build with support for deprecated APIs below the
  97. specified version number. For example "--api=1.1.0" will
  98. remove support for all APIS that were deprecated in OpenSSL
  99. version 1.1.0 or below.
  100. --cross-compile-prefix=PREFIX
  101. The PREFIX to include in front of commands for your
  102. toolchain. It's likely to have to end with dash, e.g.
  103. a-b-c- would invoke GNU compiler as a-b-c-gcc, etc.
  104. Unfortunately cross-compiling is too case-specific to
  105. put together one-size-fits-all instructions. You might
  106. have to pass more flags or set up environment variables
  107. to actually make it work. Android and iOS cases are
  108. discussed in corresponding Configurations/15-*.conf
  109. files. But there are cases when this option alone is
  110. sufficient. For example to build the mingw64 target on
  111. Linux "--cross-compile-prefix=x86_64-w64-mingw32-"
  112. works. Naturally provided that mingw packages are
  113. installed. Today Debian and Ubuntu users have option to
  114. install a number of prepackaged cross-compilers along
  115. with corresponding run-time and development packages for
  116. "alien" hardware. To give another example
  117. "--cross-compile-prefix=mipsel-linux-gnu-" suffices
  118. in such case. Needless to mention that you have to
  119. invoke ./Configure, not ./config, and pass your target
  120. name explicitly. Also, note that --openssldir refers
  121. to target's file system, not one you are building on.
  122. --debug
  123. Build OpenSSL with debugging symbols and zero optimization
  124. level.
  125. --libdir=DIR
  126. The name of the directory under the top of the installation
  127. directory tree (see the --prefix option) where libraries will
  128. be installed. By default this is "lib". Note that on Windows
  129. only ".lib" files will be stored in this location. dll files
  130. will always be installed to the "bin" directory.
  131. --openssldir=DIR
  132. Directory for OpenSSL configuration files, and also the
  133. default certificate and key store. Defaults are:
  134. Unix: /usr/local/ssl
  135. Windows: C:\Program Files\Common Files\SSL
  136. or C:\Program Files (x86)\Common Files\SSL
  137. OpenVMS: SYS$COMMON:[OPENSSL-COMMON]
  138. --prefix=DIR
  139. The top of the installation directory tree. Defaults are:
  140. Unix: /usr/local
  141. Windows: C:\Program Files\OpenSSL
  142. or C:\Program Files (x86)\OpenSSL
  143. OpenVMS: SYS$COMMON:[OPENSSL-'version']
  144. --release
  145. Build OpenSSL without debugging symbols. This is the default.
  146. --strict-warnings
  147. This is a developer flag that switches on various compiler
  148. options recommended for OpenSSL development. It only works
  149. when using gcc or clang as the compiler. If you are
  150. developing a patch for OpenSSL then it is recommended that
  151. you use this option where possible.
  152. --with-zlib-include=DIR
  153. The directory for the location of the zlib include file. This
  154. option is only necessary if enable-zlib (see below) is used
  155. and the include file is not already on the system include
  156. path.
  157. --with-zlib-lib=LIB
  158. On Unix: this is the directory containing the zlib library.
  159. If not provided the system library path will be used.
  160. On Windows: this is the filename of the zlib library (with or
  161. without a path). This flag must be provided if the
  162. zlib-dynamic option is not also used. If zlib-dynamic is used
  163. then this flag is optional and a default value ("ZLIB1") is
  164. used if not provided.
  165. On VMS: this is the filename of the zlib library (with or
  166. without a path). This flag is optional and if not provided
  167. then "GNV$LIBZSHR", "GNV$LIBZSHR32" or "GNV$LIBZSHR64" is
  168. used by default depending on the pointer size chosen.
  169. --with-rand-seed=seed1[,seed2,...]
  170. A comma separated list of seeding methods which will be tried
  171. by OpenSSL in order to obtain random input (a.k.a "entropy")
  172. for seeding its cryptographically secure random number
  173. generator (CSPRNG). The current seeding methods are:
  174. os: Use a trusted operating system entropy source.
  175. This is the default method if such an entropy
  176. source exists.
  177. getrandom: Use the L<getrandom(2)> or equivalent system
  178. call.
  179. devrandom: Use the the first device from the DEVRANDOM list
  180. which can be opened to read random bytes. The
  181. DEVRANDOM preprocessor constant expands to
  182. "/dev/urandom","/dev/random","/dev/srandom" on
  183. most unix-ish operating systems.
  184. egd: Check for an entropy generating daemon.
  185. rdcpu: Use the RDSEED or RDRAND command if provided by
  186. the CPU.
  187. librandom: Use librandom (not implemented yet).
  188. none: Disable automatic seeding. This is the default
  189. on some operating systems where no suitable
  190. entropy source exists, or no support for it is
  191. implemented yet.
  192. For more information, see the section 'Note on random number
  193. generation' at the end of this document.
  194. no-afalgeng
  195. Don't build the AFALG engine. This option will be forced if
  196. on a platform that does not support AFALG.
  197. enable-ktls
  198. Build with Kernel TLS support. This option will enable the
  199. use of the Kernel TLS data-path, which can improve
  200. performance and allow for the use of sendfile and splice
  201. system calls on TLS sockets. The Kernel may use TLS
  202. accelerators if any are available on the system.
  203. This option will be forced off on systems that do not support
  204. the Kernel TLS data-path.
  205. enable-asan
  206. Build with the Address sanitiser. This is a developer option
  207. only. It may not work on all platforms and should never be
  208. used in production environments. It will only work when used
  209. with gcc or clang and should be used in conjunction with the
  210. no-shared option.
  211. no-asm
  212. Do not use assembler code. This should be viewed as
  213. debugging/trouble-shooting option rather than production.
  214. On some platforms a small amount of assembler code may
  215. still be used even with this option.
  216. no-async
  217. Do not build support for async operations.
  218. no-autoalginit
  219. Don't automatically load all supported ciphers and digests.
  220. Typically OpenSSL will make available all of its supported
  221. ciphers and digests. For a statically linked application this
  222. may be undesirable if small executable size is an objective.
  223. This only affects libcrypto. Ciphers and digests will have to
  224. be loaded manually using EVP_add_cipher() and
  225. EVP_add_digest() if this option is used. This option will
  226. force a non-shared build.
  227. no-autoerrinit
  228. Don't automatically load all libcrypto/libssl error strings.
  229. Typically OpenSSL will automatically load human readable
  230. error strings. For a statically linked application this may
  231. be undesirable if small executable size is an objective.
  232. no-autoload-config
  233. Don't automatically load the default openssl.cnf file.
  234. Typically OpenSSL will automatically load a system config
  235. file which configures default ssl options.
  236. enable-buildtest-c++
  237. While testing, generate C++ buildtest files that
  238. simply check that the public OpenSSL header files
  239. are usable standalone with C++.
  240. Enabling this option demands extra care. For any
  241. compiler flag given directly as configuration
  242. option, you must ensure that it's valid for both
  243. the C and the C++ compiler. If not, the C++ build
  244. test will most likely break. As an alternative,
  245. you can use the language specific variables, CFLAGS
  246. and CXXFLAGS.
  247. no-capieng
  248. Don't build the CAPI engine. This option will be forced if
  249. on a platform that does not support CAPI.
  250. no-cmp
  251. Don't build support for CMP features
  252. no-cms
  253. Don't build support for CMS features
  254. no-comp
  255. Don't build support for SSL/TLS compression. If this option
  256. is left enabled (the default), then compression will only
  257. work if the zlib or zlib-dynamic options are also chosen.
  258. enable-crypto-mdebug
  259. Build support for debugging memory allocated via
  260. OPENSSL_malloc() or OPENSSL_zalloc().
  261. enable-crypto-mdebug-backtrace
  262. As for crypto-mdebug, but additionally provide backtrace
  263. information for allocated memory.
  264. TO BE USED WITH CARE: this uses GNU C functionality, and
  265. is therefore not usable for non-GNU config targets. If
  266. your build complains about the use of '-rdynamic' or the
  267. lack of header file execinfo.h, this option is not for you.
  268. ALSO NOTE that even though execinfo.h is available on your
  269. system (through Gnulib), the functions might just be stubs
  270. that do nothing.
  271. no-ct
  272. Don't build support for Certificate Transparency.
  273. no-deprecated
  274. Don't build with support for any deprecated APIs. This is the
  275. same as using "--api" and supplying the latest version
  276. number.
  277. no-dgram
  278. Don't build support for datagram based BIOs. Selecting this
  279. option will also force the disabling of DTLS.
  280. enable-devcryptoeng
  281. Build the /dev/crypto engine. It is automatically selected
  282. on BSD implementations, in which case it can be disabled with
  283. no-devcryptoeng.
  284. no-dynamic-engine
  285. Don't build the dynamically loaded engines. This only has an
  286. effect in a "shared" build
  287. no-ec
  288. Don't build support for Elliptic Curves.
  289. no-ec2m
  290. Don't build support for binary Elliptic Curves
  291. enable-ec_nistp_64_gcc_128
  292. Enable support for optimised implementations of some commonly
  293. used NIST elliptic curves.
  294. This is only supported on platforms:
  295. - with little-endian storage of non-byte types
  296. - that tolerate misaligned memory references
  297. - where the compiler:
  298. - supports the non-standard type __uint128_t
  299. - defines the built-in macro __SIZEOF_INT128__
  300. enable-egd
  301. Build support for gathering entropy from EGD (Entropy
  302. Gathering Daemon).
  303. no-engine
  304. Don't build support for loading engines.
  305. no-err
  306. Don't compile in any error strings.
  307. enable-external-tests
  308. Enable building of integration with external test suites.
  309. This is a developer option and may not work on all platforms.
  310. The only supported external test suite at the current time is
  311. the BoringSSL test suite. See the file test/README.external
  312. for further details.
  313. no-filenames
  314. Don't compile in filename and line number information (e.g.
  315. for errors and memory allocation).
  316. no-fips
  317. Don't compile the FIPS module
  318. enable-fuzz-libfuzzer, enable-fuzz-afl
  319. Build with support for fuzzing using either libfuzzer or AFL.
  320. These are developer options only. They may not work on all
  321. platforms and should never be used in production environments.
  322. See the file fuzz/README.md for further details.
  323. no-gost
  324. Don't build support for GOST based ciphersuites. Note that
  325. if this feature is enabled then GOST ciphersuites are only
  326. available if the GOST algorithms are also available through
  327. loading an externally supplied engine.
  328. no-legacy
  329. Don't build the legacy provider. Disabling this also disables
  330. the legacy algorithms: MD2 (already disabled by default).
  331. no-makedepend
  332. Don't generate dependencies.
  333. no-module
  334. Don't build any dynamically loadable engines. This also
  335. implies 'no-dynamic-engine'.
  336. no-multiblock
  337. Don't build support for writing multiple records in one
  338. go in libssl (Note: this is a different capability to the
  339. pipelining functionality).
  340. no-nextprotoneg
  341. Don't build support for the NPN TLS extension.
  342. no-ocsp
  343. Don't build support for OCSP.
  344. no-padlockeng
  345. no-hw-padlock
  346. Don't build the padlock engine.
  347. ('no-hw-padlock' is deprecated and should not be used)
  348. no-pic
  349. Don't build with support for Position Independent Code.
  350. no-pinshared By default OpenSSL will attempt to stay in memory until the
  351. process exits. This is so that libcrypto and libssl can be
  352. properly cleaned up automatically via an "atexit()" handler.
  353. The handler is registered by libcrypto and cleans up both
  354. libraries. On some platforms the atexit() handler will run on
  355. unload of libcrypto (if it has been dynamically loaded)
  356. rather than at process exit. This option can be used to stop
  357. OpenSSL from attempting to stay in memory until the process
  358. exits. This could lead to crashes if either libcrypto or
  359. libssl have already been unloaded at the point
  360. that the atexit handler is invoked, e.g. on a platform which
  361. calls atexit() on unload of the library, and libssl is
  362. unloaded before libcrypto then a crash is likely to happen.
  363. Applications can suppress running of the atexit() handler at
  364. run time by using the OPENSSL_INIT_NO_ATEXIT option to
  365. OPENSSL_init_crypto(). See the man page for it for further
  366. details.
  367. no-posix-io
  368. Don't use POSIX IO capabilities.
  369. no-psk
  370. Don't build support for Pre-Shared Key based ciphersuites.
  371. no-rdrand
  372. Don't use hardware RDRAND capabilities.
  373. no-rfc3779
  374. Don't build support for RFC3779 ("X.509 Extensions for IP
  375. Addresses and AS Identifiers")
  376. sctp
  377. Build support for SCTP
  378. no-shared
  379. Do not create shared libraries, only static ones. See "Note
  380. on shared libraries" below.
  381. no-sock
  382. Don't build support for socket BIOs
  383. no-srp
  384. Don't build support for SRP or SRP based ciphersuites.
  385. no-srtp
  386. Don't build SRTP support
  387. no-sse2
  388. Exclude SSE2 code paths from 32-bit x86 assembly modules.
  389. Normally SSE2 extension is detected at run-time, but the
  390. decision whether or not the machine code will be executed
  391. is taken solely on CPU capability vector. This means that
  392. if you happen to run OS kernel which does not support SSE2
  393. extension on Intel P4 processor, then your application
  394. might be exposed to "illegal instruction" exception.
  395. There might be a way to enable support in kernel, e.g.
  396. FreeBSD kernel can be compiled with CPU_ENABLE_SSE, and
  397. there is a way to disengage SSE2 code paths upon application
  398. start-up, but if you aim for wider "audience" running
  399. such kernel, consider no-sse2. Both the 386 and
  400. no-asm options imply no-sse2.
  401. enable-ssl-trace
  402. Build with the SSL Trace capabilities (adds the "-trace"
  403. option to s_client and s_server).
  404. no-static-engine
  405. Don't build the statically linked engines. This only
  406. has an impact when not built "shared".
  407. no-stdio
  408. Don't use anything from the C header file "stdio.h" that
  409. makes use of the "FILE" type. Only libcrypto and libssl can
  410. be built in this way. Using this option will suppress
  411. building the command line applications. Additionally since
  412. the OpenSSL tests also use the command line applications the
  413. tests will also be skipped.
  414. no-tests
  415. Don't build test programs or run any test.
  416. no-threads
  417. Don't try to build with support for multi-threaded
  418. applications.
  419. threads
  420. Build with support for multi-threaded applications. Most
  421. platforms will enable this by default. However if on a
  422. platform where this is not the case then this will usually
  423. require additional system-dependent options! See "Note on
  424. multi-threading" below.
  425. enable-trace
  426. Build with support for the integrated tracing api. See manual pages
  427. OSSL_trace_set_channel(3) and OSSL_trace_enabled(3) for details.
  428. no-ts
  429. Don't build Time Stamping Authority support.
  430. enable-ubsan
  431. Build with the Undefined Behaviour sanitiser. This is a
  432. developer option only. It may not work on all platforms and
  433. should never be used in production environments. It will only
  434. work when used with gcc or clang and should be used in
  435. conjunction with the "-DPEDANTIC" option (or the
  436. --strict-warnings option).
  437. no-ui
  438. Don't build with the "UI" capability (i.e. the set of
  439. features enabling text based prompts).
  440. enable-unit-test
  441. Enable additional unit test APIs. This should not typically
  442. be used in production deployments.
  443. no-uplink
  444. Don't build support for UPLINK interface.
  445. enable-weak-ssl-ciphers
  446. Build support for SSL/TLS ciphers that are considered "weak"
  447. (e.g. RC4 based ciphersuites).
  448. zlib
  449. Build with support for zlib compression/decompression.
  450. zlib-dynamic
  451. Like "zlib", but has OpenSSL load the zlib library
  452. dynamically when needed. This is only supported on systems
  453. where loading of shared libraries is supported.
  454. 386
  455. In 32-bit x86 builds, when generating assembly modules,
  456. use the 80386 instruction set only (the default x86 code
  457. is more efficient, but requires at least a 486). Note:
  458. This doesn't affect code generated by compiler, you're
  459. likely to complement configuration command line with
  460. suitable compiler-specific option.
  461. no-<prot>
  462. Don't build support for negotiating the specified SSL/TLS
  463. protocol (one of ssl, ssl3, tls, tls1, tls1_1, tls1_2,
  464. tls1_3, dtls, dtls1 or dtls1_2). If "no-tls" is selected then
  465. all of tls1, tls1_1, tls1_2 and tls1_3 are disabled.
  466. Similarly "no-dtls" will disable dtls1 and dtls1_2. The
  467. "no-ssl" option is synonymous with "no-ssl3". Note this only
  468. affects version negotiation. OpenSSL will still provide the
  469. methods for applications to explicitly select the individual
  470. protocol versions.
  471. no-<prot>-method
  472. As for no-<prot> but in addition do not build the methods for
  473. applications to explicitly select individual protocol
  474. versions. Note that there is no "no-tls1_3-method" option
  475. because there is no application method for TLSv1.3. Using
  476. individual protocol methods directly is deprecated.
  477. Applications should use TLS_method() instead.
  478. enable-<alg>
  479. Build with support for the specified algorithm, where <alg>
  480. is one of: md2 or rc5.
  481. no-<alg>
  482. Build without support for the specified algorithm, where
  483. <alg> is one of: aria, bf, blake2, camellia, cast, chacha,
  484. cmac, des, dh, dsa, ecdh, ecdsa, idea, md4, mdc2, ocb,
  485. poly1305, rc2, rc4, rmd160, scrypt, seed, siphash, siv, sm2,
  486. sm3, sm4 or whirlpool. The "ripemd" algorithm is deprecated
  487. and if used is synonymous with rmd160.
  488. -Dxxx, -Ixxx, -Wp, -lxxx, -Lxxx, -Wl, -rpath, -R, -framework, -static
  489. These system specific options will be recognised and
  490. passed through to the compiler to allow you to define
  491. preprocessor symbols, specify additional libraries, library
  492. directories or other compiler options. It might be worth
  493. noting that some compilers generate code specifically for
  494. processor the compiler currently executes on. This is not
  495. necessarily what you might have in mind, since it might be
  496. unsuitable for execution on other, typically older,
  497. processor. Consult your compiler documentation.
  498. Take note of the VAR=value documentation below and how
  499. these flags interact with those variables.
  500. -xxx, +xxx
  501. Additional options that are not otherwise recognised are
  502. passed through as they are to the compiler as well. Again,
  503. consult your compiler documentation.
  504. Take note of the VAR=value documentation below and how
  505. these flags interact with those variables.
  506. VAR=value
  507. Assignment of environment variable for Configure. These
  508. work just like normal environment variable assignments,
  509. but are supported on all platforms and are confined to
  510. the configuration scripts only. These assignments override
  511. the corresponding value in the inherited environment, if
  512. there is one.
  513. The following variables are used as "make variables" and
  514. can be used as an alternative to giving preprocessor,
  515. compiler and linker options directly as configuration.
  516. The following variables are supported:
  517. AR The static library archiver.
  518. ARFLAGS Flags for the static library archiver.
  519. AS The assembler compiler.
  520. ASFLAGS Flags for the assembler compiler.
  521. CC The C compiler.
  522. CFLAGS Flags for the C compiler.
  523. CXX The C++ compiler.
  524. CXXFLAGS Flags for the C++ compiler.
  525. CPP The C/C++ preprocessor.
  526. CPPFLAGS Flags for the C/C++ preprocessor.
  527. CPPDEFINES List of CPP macro definitions, separated
  528. by a platform specific character (':' or
  529. space for Unix, ';' for Windows, ',' for
  530. VMS). This can be used instead of using
  531. -D (or what corresponds to that on your
  532. compiler) in CPPFLAGS.
  533. CPPINCLUDES List of CPP inclusion directories, separated
  534. the same way as for CPPDEFINES. This can
  535. be used instead of -I (or what corresponds
  536. to that on your compiler) in CPPFLAGS.
  537. HASHBANGPERL Perl invocation to be inserted after '#!'
  538. in public perl scripts (only relevant on
  539. Unix).
  540. LD The program linker (not used on Unix, $(CC)
  541. is used there).
  542. LDFLAGS Flags for the shared library, DSO and
  543. program linker.
  544. LDLIBS Extra libraries to use when linking.
  545. Takes the form of a space separated list
  546. of library specifications on Unix and
  547. Windows, and as a comma separated list of
  548. libraries on VMS.
  549. RANLIB The library archive indexer.
  550. RC The Windows resource compiler.
  551. RCFLAGS Flags for the Windows resource compiler.
  552. RM The command to remove files and directories.
  553. These cannot be mixed with compiling / linking flags given
  554. on the command line. In other words, something like this
  555. isn't permitted.
  556. ./config -DFOO CPPFLAGS=-DBAR -DCOOKIE
  557. Backward compatibility note:
  558. To be compatible with older configuration scripts, the
  559. environment variables are ignored if compiling / linking
  560. flags are given on the command line, except for these:
  561. AR, CC, CXX, CROSS_COMPILE, HASHBANGPERL, PERL, RANLIB, RC
  562. and WINDRES
  563. For example, the following command will not see -DBAR:
  564. CPPFLAGS=-DBAR ./config -DCOOKIE
  565. However, the following will see both set variables:
  566. CC=gcc CROSS_COMPILE=x86_64-w64-mingw32- \
  567. ./config -DCOOKIE
  568. If CC is set, it is advisable to also set CXX to ensure
  569. both C and C++ compilers are in the same "family". This
  570. becomes relevant with 'enable-external-tests' and
  571. 'enable-buildtest-c++'.
  572. reconf
  573. reconfigure
  574. Reconfigure from earlier data. This fetches the previous
  575. command line options and environment from data saved in
  576. "configdata.pm", and runs the configuration process again,
  577. using these options and environment.
  578. Note: NO other option is permitted together with "reconf".
  579. This means that you also MUST use "./Configure" (or
  580. what corresponds to that on non-Unix platforms) directly
  581. to invoke this option.
  582. Note: The original configuration saves away values for ALL
  583. environment variables that were used, and if they weren't
  584. defined, they are still saved away with information that
  585. they weren't originally defined. This information takes
  586. precedence over environment variables that are defined
  587. when reconfiguring.
  588. Displaying configuration data
  589. -----------------------------
  590. The configuration script itself will say very little, and finishes by
  591. creating "configdata.pm". This perl module can be loaded by other scripts
  592. to find all the configuration data, and it can also be used as a script to
  593. display all sorts of configuration data in a human readable form.
  594. For more information, please do:
  595. $ ./configdata.pm --help # Unix
  596. or
  597. $ perl configdata.pm --help # Windows and VMS
  598. Installation in Detail
  599. ----------------------
  600. 1a. Configure OpenSSL for your operation system automatically:
  601. NOTE: This is not available on Windows.
  602. $ ./config [[ options ]] # Unix
  603. or
  604. $ @config [[ options ]] ! OpenVMS
  605. For the remainder of this text, the Unix form will be used in all
  606. examples, please use the appropriate form for your platform.
  607. This guesses at your operating system (and compiler, if necessary) and
  608. configures OpenSSL based on this guess. Run ./config -t to see
  609. if it guessed correctly. If you want to use a different compiler, you
  610. are cross-compiling for another platform, or the ./config guess was
  611. wrong for other reasons, go to step 1b. Otherwise go to step 2.
  612. On some systems, you can include debugging information as follows:
  613. $ ./config -d [[ options ]]
  614. 1b. Configure OpenSSL for your operating system manually
  615. OpenSSL knows about a range of different operating system, hardware and
  616. compiler combinations. To see the ones it knows about, run
  617. $ ./Configure # Unix
  618. or
  619. $ perl Configure # All other platforms
  620. For the remainder of this text, the Unix form will be used in all
  621. examples, please use the appropriate form for your platform.
  622. Pick a suitable name from the list that matches your system. For most
  623. operating systems there is a choice between using "cc" or "gcc". When
  624. you have identified your system (and if necessary compiler) use this name
  625. as the argument to Configure. For example, a "linux-elf" user would
  626. run:
  627. $ ./Configure linux-elf [[ options ]]
  628. If your system isn't listed, you will have to create a configuration
  629. file named Configurations/{{ something }}.conf and add the correct
  630. configuration for your system. See the available configs as examples
  631. and read Configurations/README and Configurations/README.design for
  632. more information.
  633. The generic configurations "cc" or "gcc" should usually work on 32 bit
  634. Unix-like systems.
  635. Configure creates a build file ("Makefile" on Unix, "makefile" on Windows
  636. and "descrip.mms" on OpenVMS) from a suitable template in Configurations,
  637. and defines various macros in include/openssl/opensslconf.h (generated from
  638. include/openssl/opensslconf.h.in).
  639. 1c. Configure OpenSSL for building outside of the source tree.
  640. OpenSSL can be configured to build in a build directory separate from
  641. the directory with the source code. It's done by placing yourself in
  642. some other directory and invoking the configuration commands from
  643. there.
  644. Unix example:
  645. $ mkdir /var/tmp/openssl-build
  646. $ cd /var/tmp/openssl-build
  647. $ /PATH/TO/OPENSSL/SOURCE/config [[ options ]]
  648. or
  649. $ /PATH/TO/OPENSSL/SOURCE/Configure {{ target }} [[ options ]]
  650. OpenVMS example:
  651. $ set default sys$login:
  652. $ create/dir [.tmp.openssl-build]
  653. $ set default [.tmp.openssl-build]
  654. $ @[PATH.TO.OPENSSL.SOURCE]config [[ options ]]
  655. or
  656. $ @[PATH.TO.OPENSSL.SOURCE]Configure {{ target }} [[ options ]]
  657. Windows example:
  658. $ C:
  659. $ mkdir \temp-openssl
  660. $ cd \temp-openssl
  661. $ perl d:\PATH\TO\OPENSSL\SOURCE\Configure {{ target }} [[ options ]]
  662. Paths can be relative just as well as absolute. Configure will
  663. do its best to translate them to relative paths whenever possible.
  664. 2. Build OpenSSL by running:
  665. $ make # Unix
  666. $ mms ! (or mmk) OpenVMS
  667. $ nmake # Windows
  668. This will build the OpenSSL libraries (libcrypto.a and libssl.a on
  669. Unix, corresponding on other platforms) and the OpenSSL binary
  670. ("openssl"). The libraries will be built in the top-level directory,
  671. and the binary will be in the "apps" subdirectory.
  672. Troubleshooting:
  673. If the build fails, look at the output. There may be reasons
  674. for the failure that aren't problems in OpenSSL itself (like
  675. missing standard headers).
  676. If the build succeeded previously, but fails after a source or
  677. configuration change, it might be helpful to clean the build tree
  678. before attempting another build. Use this command:
  679. $ make clean # Unix
  680. $ mms clean ! (or mmk) OpenVMS
  681. $ nmake clean # Windows
  682. Assembler error messages can sometimes be sidestepped by using the
  683. "no-asm" configuration option.
  684. Compiling parts of OpenSSL with gcc and others with the system
  685. compiler will result in unresolved symbols on some systems.
  686. If you are still having problems you can get help by sending an email
  687. to the openssl-users email list (see
  688. https://www.openssl.org/community/mailinglists.html for details). If
  689. it is a bug with OpenSSL itself, please open an issue on GitHub, at
  690. https://github.com/openssl/openssl/issues. Please review the existing
  691. ones first; maybe the bug was already reported or has already been
  692. fixed.
  693. 3. After a successful build, the libraries should be tested. Run:
  694. $ make test # Unix
  695. $ mms test ! OpenVMS
  696. $ nmake test # Windows
  697. NOTE: you MUST run the tests from an unprivileged account (or
  698. disable your privileges temporarily if your platform allows it).
  699. If some tests fail, look at the output. There may be reasons for
  700. the failure that isn't a problem in OpenSSL itself (like a
  701. malfunction with Perl). You may want increased verbosity, that
  702. can be accomplished like this:
  703. $ make VERBOSE=1 test # Unix
  704. $ mms /macro=(VERBOSE=1) test ! OpenVMS
  705. $ nmake VERBOSE=1 test # Windows
  706. If you want to run just one or a few specific tests, you can use
  707. the make variable TESTS to specify them, like this:
  708. $ make TESTS='test_rsa test_dsa' test # Unix
  709. $ mms/macro="TESTS=test_rsa test_dsa" test ! OpenVMS
  710. $ nmake TESTS='test_rsa test_dsa' test # Windows
  711. And of course, you can combine (Unix example shown):
  712. $ make VERBOSE=1 TESTS='test_rsa test_dsa' test
  713. You can find the list of available tests like this:
  714. $ make list-tests # Unix
  715. $ mms list-tests ! OpenVMS
  716. $ nmake list-tests # Windows
  717. Have a look at the manual for the perl module Test::Harness to
  718. see what other HARNESS_* variables there are.
  719. If you find a problem with OpenSSL itself, try removing any
  720. compiler optimization flags from the CFLAGS line in Makefile and
  721. run "make clean; make" or corresponding.
  722. To report a bug please open an issue on GitHub, at
  723. https://github.com/openssl/openssl/issues.
  724. For more details on how the make variables TESTS can be used,
  725. see section TESTS in Detail below.
  726. 4. If everything tests ok, install OpenSSL with
  727. $ make install # Unix
  728. $ mms install ! OpenVMS
  729. $ nmake install # Windows
  730. This will install all the software components in this directory
  731. tree under PREFIX (the directory given with --prefix or its
  732. default):
  733. Unix:
  734. bin/ Contains the openssl binary and a few other
  735. utility scripts.
  736. include/openssl
  737. Contains the header files needed if you want
  738. to build your own programs that use libcrypto
  739. or libssl.
  740. lib Contains the OpenSSL library files.
  741. lib/engines Contains the OpenSSL dynamically loadable engines.
  742. share/man/man1 Contains the OpenSSL command line man-pages.
  743. share/man/man3 Contains the OpenSSL library calls man-pages.
  744. share/man/man5 Contains the OpenSSL configuration format man-pages.
  745. share/man/man7 Contains the OpenSSL other misc man-pages.
  746. share/doc/openssl/html/man1
  747. share/doc/openssl/html/man3
  748. share/doc/openssl/html/man5
  749. share/doc/openssl/html/man7
  750. Contains the HTML rendition of the man-pages.
  751. OpenVMS ('arch' is replaced with the architecture name, "Alpha"
  752. or "ia64", 'sover' is replaced with the shared library version
  753. (0101 for 1.1), and 'pz' is replaced with the pointer size
  754. OpenSSL was built with):
  755. [.EXE.'arch'] Contains the openssl binary.
  756. [.EXE] Contains a few utility scripts.
  757. [.include.openssl]
  758. Contains the header files needed if you want
  759. to build your own programs that use libcrypto
  760. or libssl.
  761. [.LIB.'arch'] Contains the OpenSSL library files.
  762. [.ENGINES'sover''pz'.'arch']
  763. Contains the OpenSSL dynamically loadable engines.
  764. [.SYS$STARTUP] Contains startup, login and shutdown scripts.
  765. These define appropriate logical names and
  766. command symbols.
  767. [.SYSTEST] Contains the installation verification procedure.
  768. [.HTML] Contains the HTML rendition of the manual pages.
  769. Additionally, install will add the following directories under
  770. OPENSSLDIR (the directory given with --openssldir or its default)
  771. for you convenience:
  772. certs Initially empty, this is the default location
  773. for certificate files.
  774. private Initially empty, this is the default location
  775. for private key files.
  776. misc Various scripts.
  777. Package builders who want to configure the library for standard
  778. locations, but have the package installed somewhere else so that
  779. it can easily be packaged, can use
  780. $ make DESTDIR=/tmp/package-root install # Unix
  781. $ mms/macro="DESTDIR=TMP:[PACKAGE-ROOT]" install ! OpenVMS
  782. The specified destination directory will be prepended to all
  783. installation target paths.
  784. Compatibility issues with previous OpenSSL versions:
  785. * COMPILING existing applications
  786. Starting with version 1.1.0, OpenSSL hides a number of structures
  787. that were previously open. This includes all internal libssl
  788. structures and a number of EVP types. Accessor functions have
  789. been added to allow controlled access to the structures' data.
  790. This means that some software needs to be rewritten to adapt to
  791. the new ways of doing things. This often amounts to allocating
  792. an instance of a structure explicitly where you could previously
  793. allocate them on the stack as automatic variables, and using the
  794. provided accessor functions where you would previously access a
  795. structure's field directly.
  796. Some APIs have changed as well. However, older APIs have been
  797. preserved when possible.
  798. Environment Variables
  799. ---------------------
  800. A number of environment variables can be used to provide additional control
  801. over the build process. Typically these should be defined prior to running
  802. config or Configure. Not all environment variables are relevant to all
  803. platforms.
  804. AR
  805. The name of the ar executable to use.
  806. BUILDFILE
  807. Use a different build file name than the platform default
  808. ("Makefile" on Unix-like platforms, "makefile" on native Windows,
  809. "descrip.mms" on OpenVMS). This requires that there is a
  810. corresponding build file template. See Configurations/README
  811. for further information.
  812. CC
  813. The compiler to use. Configure will attempt to pick a default
  814. compiler for your platform but this choice can be overridden
  815. using this variable. Set it to the compiler executable you wish
  816. to use, e.g. "gcc" or "clang".
  817. CROSS_COMPILE
  818. This environment variable has the same meaning as for the
  819. "--cross-compile-prefix" Configure flag described above. If both
  820. are set then the Configure flag takes precedence.
  821. NM
  822. The name of the nm executable to use.
  823. OPENSSL_LOCAL_CONFIG_DIR
  824. OpenSSL comes with a database of information about how it
  825. should be built on different platforms as well as build file
  826. templates for those platforms. The database is comprised of
  827. ".conf" files in the Configurations directory. The build
  828. file templates reside there as well as ".tmpl" files. See the
  829. file Configurations/README for further information about the
  830. format of ".conf" files as well as information on the ".tmpl"
  831. files.
  832. In addition to the standard ".conf" and ".tmpl" files, it is
  833. possible to create your own ".conf" and ".tmpl" files and store
  834. them locally, outside the OpenSSL source tree. This environment
  835. variable can be set to the directory where these files are held
  836. and will be considered by Configure before it looks in the
  837. standard directories.
  838. PERL
  839. The name of the Perl executable to use when building OpenSSL.
  840. This variable is used in config script only. Configure on the
  841. other hand imposes the interpreter by which it itself was
  842. executed on the whole build procedure.
  843. HASHBANGPERL
  844. The command string for the Perl executable to insert in the
  845. #! line of perl scripts that will be publically installed.
  846. Default: /usr/bin/env perl
  847. Note: the value of this variable is added to the same scripts
  848. on all platforms, but it's only relevant on Unix-like platforms.
  849. RC
  850. The name of the rc executable to use. The default will be as
  851. defined for the target platform in the ".conf" file. If not
  852. defined then "windres" will be used. The WINDRES environment
  853. variable is synonymous to this. If both are defined then RC
  854. takes precedence.
  855. RANLIB
  856. The name of the ranlib executable to use.
  857. WINDRES
  858. See RC.
  859. Makefile targets
  860. ----------------
  861. The Configure script generates a Makefile in a format relevant to the specific
  862. platform. The Makefiles provide a number of targets that can be used. Not all
  863. targets may be available on all platforms. Only the most common targets are
  864. described here. Examine the Makefiles themselves for the full list.
  865. all
  866. The default target to build all the software components.
  867. clean
  868. Remove all build artefacts and return the directory to a "clean"
  869. state.
  870. depend
  871. Rebuild the dependencies in the Makefiles. This is a legacy
  872. option that no longer needs to be used since OpenSSL 1.1.0.
  873. install
  874. Install all OpenSSL components.
  875. install_sw
  876. Only install the OpenSSL software components.
  877. install_docs
  878. Only install the OpenSSL documentation components.
  879. install_man_docs
  880. Only install the OpenSSL man pages (Unix only).
  881. install_html_docs
  882. Only install the OpenSSL html documentation.
  883. list-tests
  884. Prints a list of all the self test names.
  885. test
  886. Build and run the OpenSSL self tests.
  887. uninstall
  888. Uninstall all OpenSSL components.
  889. reconfigure
  890. reconf
  891. Re-run the configuration process, as exactly as the last time
  892. as possible.
  893. update
  894. This is a developer option. If you are developing a patch for
  895. OpenSSL you may need to use this if you want to update
  896. automatically generated files; add new error codes or add new
  897. (or change the visibility of) public API functions. (Unix only).
  898. TESTS in Detail
  899. ---------------
  900. The make variable TESTS supports a versatile set of space separated tokens
  901. with which you can specify a set of tests to be performed. With a "current
  902. set of tests" in mind, initially being empty, here are the possible tokens:
  903. alltests The current set of tests becomes the whole set of available
  904. tests (as listed when you do 'make list-tests' or similar).
  905. xxx Adds the test 'xxx' to the current set of tests.
  906. -xxx Removes 'xxx' from the current set of tests. If this is the
  907. first token in the list, the current set of tests is first
  908. assigned the whole set of available tests, effectively making
  909. this token equivalent to TESTS="alltests -xxx".
  910. nn Adds the test group 'nn' (which is a number) to the current
  911. set of tests.
  912. -nn Removes the test group 'nn' from the current set of tests.
  913. If this is the first token in the list, the current set of
  914. tests is first assigned the whole set of available tests,
  915. effectively making this token equivalent to
  916. TESTS="alltests -xxx".
  917. Also, all tokens except for "alltests" may have wildcards, such as *.
  918. (on Unix and Windows, BSD style wildcards are supported, while on VMS,
  919. it's VMS style wildcards)
  920. Example: All tests except for the fuzz tests:
  921. $ make TESTS=-test_fuzz test
  922. or (if you want to be explicit)
  923. $ make TESTS='alltests -test_fuzz' test
  924. Example: All tests that have a name starting with "test_ssl" but not those
  925. starting with "test_ssl_":
  926. $ make TESTS='test_ssl* -test_ssl_*' test
  927. Example: Only test group 10:
  928. $ make TESTS='10'
  929. Example: All tests except the slow group (group 99):
  930. $ make TESTS='-99'
  931. Example: All tests in test groups 80 to 99 except for tests in group 90:
  932. $ make TESTS='[89]? -90'
  933. To stochastically verify that the algorithm that produces uniformly distributed
  934. random numbers is operating correctly (with a false positive rate of 0.01%):
  935. $ ./util/shlib_wrap.sh test/bntest -stochastic
  936. Note on multi-threading
  937. -----------------------
  938. For some systems, the OpenSSL Configure script knows what compiler options
  939. are needed to generate a library that is suitable for multi-threaded
  940. applications. On these systems, support for multi-threading is enabled
  941. by default; use the "no-threads" option to disable (this should never be
  942. necessary).
  943. On other systems, to enable support for multi-threading, you will have
  944. to specify at least two options: "threads", and a system-dependent option.
  945. (The latter is "-D_REENTRANT" on various systems.) The default in this
  946. case, obviously, is not to include support for multi-threading (but
  947. you can still use "no-threads" to suppress an annoying warning message
  948. from the Configure script.)
  949. OpenSSL provides built-in support for two threading models: pthreads (found on
  950. most UNIX/Linux systems), and Windows threads. No other threading models are
  951. supported. If your platform does not provide pthreads or Windows threads then
  952. you should Configure with the "no-threads" option.
  953. Notes on shared libraries
  954. -------------------------
  955. For most systems the OpenSSL Configure script knows what is needed to
  956. build shared libraries for libcrypto and libssl. On these systems
  957. the shared libraries will be created by default. This can be suppressed and
  958. only static libraries created by using the "no-shared" option. On systems
  959. where OpenSSL does not know how to build shared libraries the "no-shared"
  960. option will be forced and only static libraries will be created.
  961. Shared libraries are named a little differently on different platforms.
  962. One way or another, they all have the major OpenSSL version number as
  963. part of the file name, i.e. for OpenSSL 1.1.x, 1.1 is somehow part of
  964. the name.
  965. On most POSIX platforms, shared libraries are named libcrypto.so.1.1
  966. and libssl.so.1.1.
  967. on Cygwin, shared libraries are named cygcrypto-1.1.dll and cygssl-1.1.dll
  968. with import libraries libcrypto.dll.a and libssl.dll.a.
  969. On Windows build with MSVC or using MingW, shared libraries are named
  970. libcrypto-1_1.dll and libssl-1_1.dll for 32-bit Windows, libcrypto-1_1-x64.dll
  971. and libssl-1_1-x64.dll for 64-bit x86_64 Windows, and libcrypto-1_1-ia64.dll
  972. and libssl-1_1-ia64.dll for IA64 Windows. With MSVC, the import libraries
  973. are named libcrypto.lib and libssl.lib, while with MingW, they are named
  974. libcrypto.dll.a and libssl.dll.a.
  975. On VMS, shareable images (VMS speak for shared libraries) are named
  976. ossl$libcrypto0101_shr.exe and ossl$libssl0101_shr.exe. However, when
  977. OpenSSL is specifically built for 32-bit pointers, the shareable images
  978. are named ossl$libcrypto0101_shr32.exe and ossl$libssl0101_shr32.exe
  979. instead, and when built for 64-bit pointers, they are named
  980. ossl$libcrypto0101_shr64.exe and ossl$libssl0101_shr64.exe.
  981. Note on random number generation
  982. --------------------------------
  983. Availability of cryptographically secure random numbers is required for
  984. secret key generation. OpenSSL provides several options to seed the
  985. internal CSPRNG. If not properly seeded, the internal CSPRNG will refuse
  986. to deliver random bytes and a "PRNG not seeded error" will occur.
  987. The seeding method can be configured using the --with-rand-seed option,
  988. which can be used to specify a comma separated list of seed methods.
  989. However in most cases OpenSSL will choose a suitable default method,
  990. so it is not necessary to explicitly provide this option. Note also
  991. that not all methods are available on all platforms.
  992. I) On operating systems which provide a suitable randomness source (in
  993. form of a system call or system device), OpenSSL will use the optimal
  994. available method to seed the CSPRNG from the operating system's
  995. randomness sources. This corresponds to the option --with-rand-seed=os.
  996. II) On systems without such a suitable randomness source, automatic seeding
  997. and reseeding is disabled (--with-rand-seed=none) and it may be necessary
  998. to install additional support software to obtain a random seed and reseed
  999. the CSPRNG manually. Please check out the manual pages for RAND_add(),
  1000. RAND_bytes(), RAND_egd(), and the FAQ for more information.