4 This directory contains a few sets of files that are used for
5 configuration in diverse ways:
7 *.conf Target platform configurations, please read
8 'Configurations of OpenSSL target platforms' for more
10 *.tmpl Build file templates, please read 'Build-file
11 programming with the "unified" build system' as well
12 as 'Build info files' for more information.
13 *.pm Helper scripts / modules for the main `Configure`
14 script. See 'Configure helper scripts for more
18 Configurations of OpenSSL target platforms
19 ==========================================
21 Configuration targets are a collection of facts that we know about
22 different platforms and their capabilities. We organise them in a
23 hash table, where each entry represent a specific target.
25 Note that configuration target names must be unique across all config
26 files. The Configure script does check that a config file doesn't
27 have config targets that shadow config targets from other files.
29 In each table entry, the following keys are significant:
31 inherit_from => Other targets to inherit values from.
32 Explained further below. [1]
33 template => Set to 1 if this isn't really a platform
34 target. Instead, this target is a template
35 upon which other targets can be built.
36 Explained further below. [1]
38 sys_id => System identity for systems where that
39 is difficult to determine automatically.
41 enable => Enable specific configuration features.
42 This MUST be an array of words.
43 disable => Disable specific configuration features.
44 This MUST be an array of words.
45 Note: if the same feature is both enabled
46 and disabled, disable wins.
48 as => The assembler command. This is not always
49 used (for example on Unix, where the C
50 compiler is used instead).
51 asflags => Default assembler command flags [4].
52 cpp => The C preprocessor command, normally not
53 given, as the build file defaults are
55 cppflags => Default C preprocessor flags [4].
56 defines => As an alternative, macro definitions may be
57 given here instead of in `cppflags' [4].
58 If given here, they MUST be as an array of
59 the string such as "MACRO=value", or just
60 "MACRO" for definitions without value.
61 includes => As an alternative, inclusion directories
62 may be given here instead of in `cppflags'
63 [4]. If given here, the MUST be an array
64 of strings, one directory specification
66 cc => The C compiler command, usually one of "cc",
67 "gcc" or "clang". This command is normally
68 also used to link object files and
69 libraries into the final program.
70 cxx => The C++ compiler command, usually one of
71 "c++", "g++" or "clang++". This command is
72 also used when linking a program where at
73 least one of the object file is made from
75 cflags => Defaults C compiler flags [4].
76 cxxflags => Default C++ compiler flags [4]. If unset,
77 it gets the same value as cflags.
79 (linking is a complex thing, see [3] below)
80 ld => Linker command, usually not defined
81 (meaning the compiler command is used
83 (NOTE: this is here for future use, it's
85 lflags => Default flags used when linking apps,
86 shared libraries or DSOs [4].
87 ex_libs => Extra libraries that are needed when
88 linking shared libraries, DSOs or programs.
89 The value is also assigned to Libs.private
90 in $(libdir)/pkgconfig/libcrypto.pc.
92 shared_cppflags => Extra C preprocessor flags used when
93 processing C files for shared libraries.
94 shared_cflag => Extra C compiler flags used when compiling
95 for shared libraries, typically something
97 shared_ldflag => Extra linking flags used when linking
101 module_ldflags => Has the same function as the corresponding
102 `shared_' attributes, but for building DSOs.
103 When unset, they get the same values as the
104 corresponding `shared_' attributes.
106 ar => The library archive command, the default is
108 (NOTE: this is here for future use, it's
110 arflags => Flags to be used with the library archive
111 command. On Unix, this includes the
112 command letter, 'r' by default.
114 ranlib => The library archive indexing command, the
115 default is 'ranlib' it it exists.
117 unistd => An alternative header to the typical
118 '<unistd.h>'. This is very rarely needed.
120 shared_extension => File name extension used for shared
122 obj_extension => File name extension used for object files.
123 On unix, this defaults to ".o" (NOTE: this
124 is here for future use, it's not
126 exe_extension => File name extension used for executable
127 files. On unix, this defaults to "" (NOTE:
128 this is here for future use, it's not
130 shlib_variant => A "variant" identifier inserted between the base
131 shared library name and the extension. On "unixy"
132 platforms (BSD, Linux, Solaris, MacOS/X, ...) this
133 supports installation of custom OpenSSL libraries
134 that don't conflict with other builds of OpenSSL
135 installed on the system. The variant identifier
136 becomes part of the SONAME of the library and also
137 any symbol versions (symbol versions are not used or
138 needed with MacOS/X). For example, on a system
139 where a default build would normally create the SSL
140 shared library as 'libssl.so -> libssl.so.1.1' with
141 the value of the symlink as the SONAME, a target
142 definition that sets 'shlib_variant => "-abc"' will
143 create 'libssl.so -> libssl-abc.so.1.1', again with
144 an SONAME equal to the value of the symlink. The
145 symbol versions associated with the variant library
146 would then be 'OPENSSL_ABC_<version>' rather than
147 the default 'OPENSSL_<version>'. The string inserted
148 into symbol versions is obtained by mapping all
149 letters in the "variant" identifier to upper case
150 and all non-alphanumeric characters to '_'.
152 thread_scheme => The type of threads is used on the
153 configured platform. Currently known
154 values are "(unknown)", "pthreads",
155 "uithreads" (a.k.a solaris threads) and
156 "winthreads". Except for "(unknown)", the
157 actual value is currently ignored but may
158 be used in the future. See further notes
160 dso_scheme => The type of dynamic shared objects to build
161 for. This mostly comes into play with
162 modules, but can be used for other purposes
163 as well. Valid values are "DLFCN"
164 (dlopen() et al), "DLFCN_NO_H" (for systems
165 that use dlopen() et al but do not have
166 fcntl.h), "DL" (shl_load() et al), "WIN32"
168 asm_arch => The architecture to be used for compiling assembly
169 source. This acts as a selector in build.info files.
170 uplink_arch => The architecture to be used for compiling uplink
171 source. This acts as a selector in build.info files.
172 This is separate from asm_arch because it's compiled
173 even when 'no-asm' is given, even though it contains
175 perlasm_scheme => The perlasm method used to create the
176 assembler files used when compiling with
177 assembler implementations.
178 shared_target => The shared library building method used.
179 This serves multiple purposes:
180 - as index for targets found in shared_info.pl.
181 - as linker script generation selector.
182 To serve both purposes, the index for shared_info.pl
183 should end with '-shared', and this suffix will be
184 removed for use as a linker script generation
185 selector. Note that the latter is only used if
186 'shared_defflag' is defined.
187 build_scheme => The scheme used to build up a Makefile.
188 In its simplest form, the value is a string
189 with the name of the build scheme.
190 The value may also take the form of a list
191 of strings, if the build_scheme is to have
192 some options. In this case, the first
193 string in the list is the name of the build
195 Currently recognised build scheme is "unified".
196 For the "unified" build scheme, this item
197 *must* be an array with the first being the
198 word "unified" and the second being a word
199 to identify the platform family.
201 multilib => On systems that support having multiple
202 implementations of a library (typically a
203 32-bit and a 64-bit variant), this is used
204 to have the different variants in different
207 bn_ops => Building options (was just bignum options in
208 the earlier history of this option, hence the
209 name). This is a string of words that describe
210 algorithms' implementation parameters that
211 are optimal for the designated target platform,
212 such as the type of integers used to build up
213 the bignum, different ways to implement certain
214 ciphers and so on. To fully comprehend the
215 meaning, the best is to read the affected
219 THIRTY_TWO_BIT bignum limbs are 32 bits,
220 this is default if no
221 option is specified, it
222 works on any supported
223 system [unless "wider"
224 limb size is implied in
226 BN_LLONG bignum limbs are 32 bits,
227 but 64-bit 'unsigned long
228 long' is used internally
230 SIXTY_FOUR_BIT_LONG bignum limbs are 64 bits
231 and sizeof(long) is 8;
232 SIXTY_FOUR_BIT bignums limbs are 64 bits,
233 but execution environment
235 RC4_CHAR RC4 key schedule is made
236 up of 'unsigned char's;
237 RC4_INT RC4 key schedule is made
238 up of 'unsigned int's;
239 EXPORT_VAR_AS_FN for shared libraries,
243 modes_asm_src => Assembler implementation of cipher modes,
244 currently the functions gcm_gmult_4bit and
246 padlock_asm_src => Assembler implementation of core parts of
247 the padlock engine. This is mandatory on
248 any platform where the padlock engine might
252 [1] as part of the target configuration, one can have a key called
253 'inherit_from' that indicate what other configurations to inherit
254 data from. These are resolved recursively.
256 Inheritance works as a set of default values that can be overridden
257 by corresponding key values in the inheriting configuration.
259 Note 1: any configuration table can be used as a template.
260 Note 2: pure templates have the attribute 'template => 1' and
261 cannot be used as build targets.
263 If several configurations are given in the 'inherit_from' array,
264 the values of same attribute are concatenated with space
265 separation. With this, it's possible to have several smaller
266 templates for different configuration aspects that can be combined
267 into a complete configuration.
269 instead of a scalar value or an array, a value can be a code block
270 of the form 'sub { /* your code here */ }'. This code block will
271 be called with the list of inherited values for that key as
272 arguments. In fact, the concatenation of strings is really done
273 by using 'sub { join(" ",@_) }' on the list of inherited values.
281 ignored => "This should not appear in the end result",
290 inherit_from => [ "foo", "bar" ],
291 hehe => sub { join(" ",(@_,"!!!")) },
295 The entry for "laughter" will become as follows after processing:
304 [2] OpenSSL is built with threading capabilities unless the user
305 specifies 'no-threads'. The value of the key 'thread_scheme' may
306 be "(unknown)", in which case the user MUST give some compilation
309 [3] OpenSSL has three types of things to link from object files or
312 - shared libraries; that would be libcrypto and libssl.
313 - shared objects (sometimes called dynamic libraries); that would
315 - applications; those are apps/openssl and all the test apps.
317 Very roughly speaking, linking is done like this (words in braces
318 represent the configuration settings documented at the beginning
322 {ld} $(CFLAGS) {lflags} {shared_ldflag} -o libfoo.so \
323 foo/something.o foo/somethingelse.o {ex_libs}
326 {ld} $(CFLAGS) {lflags} {module_ldflags} -o libeng.so \
327 blah1.o blah2.o -lcrypto {ex_libs}
330 {ld} $(CFLAGS) {lflags} -o app \
331 app1.o utils.o -lssl -lcrypto {ex_libs}
333 [4] There are variants of these attribute, prefixed with `lib_',
334 `dso_' or `bin_'. Those variants replace the unprefixed attribute
335 when building library, DSO or program modules specifically.
337 Historically, the target configurations came in form of a string with
338 values separated by colons. This use is deprecated. The string form
341 "target" => "{cc}:{cflags}:{unistd}:{thread_cflag}:{sys_id}:{lflags}:{bn_ops}:{cpuid_obj}:{bn_obj}:{ec_obj}:{des_obj}:{aes_obj}:{bf_obj}:{md5_obj}:{sha1_obj}:{cast_obj}:{rc4_obj}:{rmd160_obj}:{rc5_obj}:{wp_obj}:{cmll_obj}:{modes_obj}:{padlock_obj}:{perlasm_scheme}:{dso_scheme}:{shared_target}:{shared_cflag}:{shared_ldflag}:{shared_extension}:{ranlib}:{arflags}:{multilib}"
347 The build.info files that are spread over the source tree contain the
348 minimum information needed to build and distribute OpenSSL. It uses a
349 simple and yet fairly powerful language to determine what needs to be
350 built, from what sources, and other relationships between files.
352 For every build.info file, all file references are relative to the
353 directory of the build.info file for source files, and the
354 corresponding build directory for built files if the build tree
355 differs from the source tree.
357 When processed, every line is processed with the perl module
358 Text::Template, using the delimiters "{-" and "-}". The hashes
359 %config and %target are passed to the perl fragments, along with
360 $sourcedir and $builddir, which are the locations of the source
361 directory for the current build.info file and the corresponding build
362 directory, all relative to the top of the build tree.
364 'Configure' only knows inherently about the top build.info file. For
365 any other directory that has one, further directories to look into
366 must be indicated like this:
368 SUBDIRS=something someelse
370 On to things to be built; they are declared by setting specific
378 Note that the files mentioned for PROGRAMS, LIBS and MODULES *must* be
379 without extensions. The build file templates will figure them out.
381 For each thing to be built, it is then possible to say what sources
385 SOURCE[foo]=foo.c common.c
386 SOURCE[bar]=bar.c extra.c common.c
388 It's also possible to tell some other dependencies:
390 DEPEND[foo]=libsomething
391 DEPEND[libbar]=libsomethingelse
393 (it could be argued that 'libsomething' and 'libsomethingelse' are
394 source as well. However, the files given through SOURCE are expected
395 to be located in the source tree while files given through DEPEND are
396 expected to be located in the build tree)
398 It's also possible to depend on static libraries explicitly:
400 DEPEND[foo]=libsomething.a
401 DEPEND[libbar]=libsomethingelse.a
403 This should be rarely used, and care should be taken to make sure it's
404 only used when supported. For example, native Windows build doesn't
405 support building static libraries and DLLs at the same time, so using
406 static libraries on Windows can only be done when configured
409 In some cases, it's desirable to include some source files in the
410 shared form of a library only:
412 SHARED_SOURCE[libfoo]=dllmain.c
414 For any file to be built, it's also possible to tell what extra
415 include paths the build of their source files should use:
419 It's also possible to specify C macros that should be defined:
421 DEFINE[foo]=FOO BAR=1
423 In some cases, one might want to generate some source files from
424 others, that's done as follows:
426 GENERATE[foo.s]=asm/something.pl $(CFLAGS)
427 GENERATE[bar.s]=asm/bar.S
429 The value of each GENERATE line is a command line or part of it.
430 Configure places no rules on the command line, except that the first
431 item must be the generator file. It is, however, entirely up to the
432 build file template to define exactly how those command lines should
433 be handled, how the output is captured and so on.
435 Sometimes, the generator file itself depends on other files, for
436 example if it is a perl script that depends on other perl modules.
437 This can be expressed using DEPEND like this:
439 DEPEND[asm/something.pl]=../perlasm/Foo.pm
441 There may also be cases where the exact file isn't easily specified,
442 but an inclusion directory still needs to be specified. INCLUDE can
443 be used in that case:
445 INCLUDE[asm/something.pl]=../perlasm
447 NOTE: GENERATE lines are limited to one command only per GENERATE.
449 Finally, you can have some simple conditional use of the build.info
450 information, looking like this:
460 The expression in square brackets is interpreted as a string in perl,
461 and will be seen as true if perl thinks it is, otherwise false. For
462 example, the above would have "something" used, since 1 is true.
464 Together with the use of Text::Template, this can be used as
465 conditions based on something in the passed variables, for example:
467 IF[{- $disabled{shared} -}]
469 SOURCE[libcrypto]=...
476 Build-file programming with the "unified" build system
477 ======================================================
479 "Build files" are called "Makefile" on Unix-like operating systems,
480 "descrip.mms" for MMS on VMS, "makefile" for nmake on Windows, etc.
482 To use the "unified" build system, the target configuration needs to
483 set the three items 'build_scheme', 'build_file' and 'build_command'.
484 In the rest of this section, we will assume that 'build_scheme' is set
485 to "unified" (see the configurations documentation above for the
488 For any name given by 'build_file', the "unified" system expects a
489 template file in Configurations/ named like the build file, with
490 ".tmpl" appended, or in case of possible ambiguity, a combination of
491 the second 'build_scheme' list item and the 'build_file' name. For
492 example, if 'build_file' is set to "Makefile", the template could be
493 Configurations/Makefile.tmpl or Configurations/unix-Makefile.tmpl.
494 In case both Configurations/unix-Makefile.tmpl and
495 Configurations/Makefile.tmpl are present, the former takes
498 The build-file template is processed with the perl module
499 Text::Template, using "{-" and "-}" as delimiters that enclose the
500 perl code fragments that generate configuration-dependent content.
501 Those perl fragments have access to all the hash variables from
504 The build-file template is expected to define at least the following
505 perl functions in a perl code fragment enclosed with "{-" and "-}".
506 They are all expected to return a string with the lines they produce.
508 generatesrc - function that produces build file lines to generate
509 a source file from some input.
511 It's called like this:
513 generatesrc(src => "PATH/TO/tobegenerated",
514 generator => [ "generatingfile", ... ]
515 generator_incs => [ "INCL/PATH", ... ]
516 generator_deps => [ "dep1", ... ]
517 generator => [ "generatingfile", ... ]
518 incs => [ "INCL/PATH", ... ],
519 deps => [ "dep1", ... ],
520 intent => one of "libs", "dso", "bin" );
522 'src' has the name of the file to be generated.
523 'generator' is the command or part of command to
524 generate the file, of which the first item is
525 expected to be the file to generate from.
526 generatesrc() is expected to analyse and figure out
527 exactly how to apply that file and how to capture
528 the result. 'generator_incs' and 'generator_deps'
529 are include directories and files that the generator
530 file itself depends on. 'incs' and 'deps' are
531 include directories and files that are used if $(CC)
532 is used as an intermediary step when generating the
533 end product (the file indicated by 'src'). 'intent'
534 indicates what the generated file is going to be
537 src2obj - function that produces build file lines to build an
538 object file from source files and associated data.
540 It's called like this:
542 src2obj(obj => "PATH/TO/objectfile",
543 srcs => [ "PATH/TO/sourcefile", ... ],
544 deps => [ "dep1", ... ],
545 incs => [ "INCL/PATH", ... ]
546 intent => one of "lib", "dso", "bin" );
548 'obj' has the intended object file with '.o'
549 extension, src2obj() is expected to change it to
550 something more suitable for the platform.
551 'srcs' has the list of source files to build the
552 object file, with the first item being the source
553 file that directly corresponds to the object file.
554 'deps' is a list of explicit dependencies. 'incs'
555 is a list of include file directories. Finally,
556 'intent' indicates what this object file is going
559 obj2lib - function that produces build file lines to build a
560 static library file ("libfoo.a" in Unix terms) from
565 obj2lib(lib => "PATH/TO/libfile",
566 objs => [ "PATH/TO/objectfile", ... ]);
568 'lib' has the intended library file name *without*
569 extension, obj2lib is expected to add that. 'objs'
570 has the list of object files to build this library.
572 libobj2shlib - backward compatibility function that's used the
573 same way as obj2shlib (described next), and was
574 expected to build the shared library from the
575 corresponding static library when that was suitable.
576 NOTE: building a shared library from a static
577 library is now DEPRECATED, as they no longer share
578 object files. Attempting to do this will fail.
580 obj2shlib - function that produces build file lines to build a
581 shareable object library file ("libfoo.so" in Unix
582 terms) from the corresponding object files.
586 obj2shlib(shlib => "PATH/TO/shlibfile",
587 lib => "PATH/TO/libfile",
588 objs => [ "PATH/TO/objectfile", ... ],
589 deps => [ "PATH/TO/otherlibfile", ... ]);
591 'lib' has the base (static) library ffile name
592 *without* extension. This is useful in case
593 supporting files are needed (such as import
594 libraries on Windows).
595 'shlib' has the corresponding shared library name
596 *without* extension. 'deps' has the list of other
597 libraries (also *without* extension) this library
598 needs to be linked with. 'objs' has the list of
599 object files to build this library.
601 obj2dso - function that produces build file lines to build a
602 dynamic shared object file from object files.
606 obj2dso(lib => "PATH/TO/libfile",
607 objs => [ "PATH/TO/objectfile", ... ],
608 deps => [ "PATH/TO/otherlibfile",
611 This is almost the same as obj2shlib, but the
612 intent is to build a shareable library that can be
613 loaded in runtime (a "plugin"...).
615 obj2bin - function that produces build file lines to build an
616 executable file from object files.
620 obj2bin(bin => "PATH/TO/binfile",
621 objs => [ "PATH/TO/objectfile", ... ],
622 deps => [ "PATH/TO/libfile", ... ]);
624 'bin' has the intended executable file name
625 *without* extension, obj2bin is expected to add
626 that. 'objs' has the list of object files to build
627 this library. 'deps' has the list of library files
628 (also *without* extension) that the programs needs
631 in2script - function that produces build file lines to build a
632 script file from some input.
636 in2script(script => "PATH/TO/scriptfile",
637 sources => [ "PATH/TO/infile", ... ]);
639 'script' has the intended script file name.
640 'sources' has the list of source files to build the
641 resulting script from.
643 In all cases, file file paths are relative to the build tree top, and
644 the build file actions run with the build tree top as current working
647 Make sure to end the section with these functions with a string that
648 you thing is appropriate for the resulting build file. If nothing
649 else, end it like this:
651 ""; # Make sure no lingering values end up in the Makefile
655 Configure helper scripts
656 ========================
658 Configure uses helper scripts in this directory:
663 These scripts are per platform family, to check the integrity of the
664 tools used for configuration and building. The checker script used is
665 either {build_platform}-{build_file}-checker.pm or
666 {build_platform}-checker.pm, where {build_platform} is the second
667 'build_scheme' list element from the configuration target data, and
668 {build_file} is 'build_file' from the same target data.
670 If the check succeeds, the script is expected to end with a non-zero
671 expression. If the check fails, the script can end with a zero, or