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 cmll_asm_src => Assembler implementation of core CAMELLIA
245 Defaults to 'camellia.c cmll_misc.c cmll_cbc.c'
246 modes_asm_src => Assembler implementation of cipher modes,
247 currently the functions gcm_gmult_4bit and
249 padlock_asm_src => Assembler implementation of core parts of
250 the padlock engine. This is mandatory on
251 any platform where the padlock engine might
255 [1] as part of the target configuration, one can have a key called
256 'inherit_from' that indicate what other configurations to inherit
257 data from. These are resolved recursively.
259 Inheritance works as a set of default values that can be overridden
260 by corresponding key values in the inheriting configuration.
262 Note 1: any configuration table can be used as a template.
263 Note 2: pure templates have the attribute 'template => 1' and
264 cannot be used as build targets.
266 If several configurations are given in the 'inherit_from' array,
267 the values of same attribute are concatenated with space
268 separation. With this, it's possible to have several smaller
269 templates for different configuration aspects that can be combined
270 into a complete configuration.
272 instead of a scalar value or an array, a value can be a code block
273 of the form 'sub { /* your code here */ }'. This code block will
274 be called with the list of inherited values for that key as
275 arguments. In fact, the concatenation of strings is really done
276 by using 'sub { join(" ",@_) }' on the list of inherited values.
284 ignored => "This should not appear in the end result",
293 inherit_from => [ "foo", "bar" ],
294 hehe => sub { join(" ",(@_,"!!!")) },
298 The entry for "laughter" will become as follows after processing:
307 [2] OpenSSL is built with threading capabilities unless the user
308 specifies 'no-threads'. The value of the key 'thread_scheme' may
309 be "(unknown)", in which case the user MUST give some compilation
312 [3] OpenSSL has three types of things to link from object files or
315 - shared libraries; that would be libcrypto and libssl.
316 - shared objects (sometimes called dynamic libraries); that would
318 - applications; those are apps/openssl and all the test apps.
320 Very roughly speaking, linking is done like this (words in braces
321 represent the configuration settings documented at the beginning
325 {ld} $(CFLAGS) {lflags} {shared_ldflag} -o libfoo.so \
326 foo/something.o foo/somethingelse.o {ex_libs}
329 {ld} $(CFLAGS) {lflags} {module_ldflags} -o libeng.so \
330 blah1.o blah2.o -lcrypto {ex_libs}
333 {ld} $(CFLAGS) {lflags} -o app \
334 app1.o utils.o -lssl -lcrypto {ex_libs}
336 [4] There are variants of these attribute, prefixed with `lib_',
337 `dso_' or `bin_'. Those variants replace the unprefixed attribute
338 when building library, DSO or program modules specifically.
340 Historically, the target configurations came in form of a string with
341 values separated by colons. This use is deprecated. The string form
344 "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}"
350 The build.info files that are spread over the source tree contain the
351 minimum information needed to build and distribute OpenSSL. It uses a
352 simple and yet fairly powerful language to determine what needs to be
353 built, from what sources, and other relationships between files.
355 For every build.info file, all file references are relative to the
356 directory of the build.info file for source files, and the
357 corresponding build directory for built files if the build tree
358 differs from the source tree.
360 When processed, every line is processed with the perl module
361 Text::Template, using the delimiters "{-" and "-}". The hashes
362 %config and %target are passed to the perl fragments, along with
363 $sourcedir and $builddir, which are the locations of the source
364 directory for the current build.info file and the corresponding build
365 directory, all relative to the top of the build tree.
367 'Configure' only knows inherently about the top build.info file. For
368 any other directory that has one, further directories to look into
369 must be indicated like this:
371 SUBDIRS=something someelse
373 On to things to be built; they are declared by setting specific
381 Note that the files mentioned for PROGRAMS, LIBS and MODULES *must* be
382 without extensions. The build file templates will figure them out.
384 For each thing to be built, it is then possible to say what sources
388 SOURCE[foo]=foo.c common.c
389 SOURCE[bar]=bar.c extra.c common.c
391 It's also possible to tell some other dependencies:
393 DEPEND[foo]=libsomething
394 DEPEND[libbar]=libsomethingelse
396 (it could be argued that 'libsomething' and 'libsomethingelse' are
397 source as well. However, the files given through SOURCE are expected
398 to be located in the source tree while files given through DEPEND are
399 expected to be located in the build tree)
401 It's also possible to depend on static libraries explicitly:
403 DEPEND[foo]=libsomething.a
404 DEPEND[libbar]=libsomethingelse.a
406 This should be rarely used, and care should be taken to make sure it's
407 only used when supported. For example, native Windows build doesn't
408 support building static libraries and DLLs at the same time, so using
409 static libraries on Windows can only be done when configured
412 In some cases, it's desirable to include some source files in the
413 shared form of a library only:
415 SHARED_SOURCE[libfoo]=dllmain.c
417 For any file to be built, it's also possible to tell what extra
418 include paths the build of their source files should use:
422 It's also possible to specify C macros that should be defined:
424 DEFINE[foo]=FOO BAR=1
426 In some cases, one might want to generate some source files from
427 others, that's done as follows:
429 GENERATE[foo.s]=asm/something.pl $(CFLAGS)
430 GENERATE[bar.s]=asm/bar.S
432 The value of each GENERATE line is a command line or part of it.
433 Configure places no rules on the command line, except that the first
434 item must be the generator file. It is, however, entirely up to the
435 build file template to define exactly how those command lines should
436 be handled, how the output is captured and so on.
438 Sometimes, the generator file itself depends on other files, for
439 example if it is a perl script that depends on other perl modules.
440 This can be expressed using DEPEND like this:
442 DEPEND[asm/something.pl]=../perlasm/Foo.pm
444 There may also be cases where the exact file isn't easily specified,
445 but an inclusion directory still needs to be specified. INCLUDE can
446 be used in that case:
448 INCLUDE[asm/something.pl]=../perlasm
450 NOTE: GENERATE lines are limited to one command only per GENERATE.
452 Finally, you can have some simple conditional use of the build.info
453 information, looking like this:
463 The expression in square brackets is interpreted as a string in perl,
464 and will be seen as true if perl thinks it is, otherwise false. For
465 example, the above would have "something" used, since 1 is true.
467 Together with the use of Text::Template, this can be used as
468 conditions based on something in the passed variables, for example:
470 IF[{- $disabled{shared} -}]
472 SOURCE[libcrypto]=...
479 Build-file programming with the "unified" build system
480 ======================================================
482 "Build files" are called "Makefile" on Unix-like operating systems,
483 "descrip.mms" for MMS on VMS, "makefile" for nmake on Windows, etc.
485 To use the "unified" build system, the target configuration needs to
486 set the three items 'build_scheme', 'build_file' and 'build_command'.
487 In the rest of this section, we will assume that 'build_scheme' is set
488 to "unified" (see the configurations documentation above for the
491 For any name given by 'build_file', the "unified" system expects a
492 template file in Configurations/ named like the build file, with
493 ".tmpl" appended, or in case of possible ambiguity, a combination of
494 the second 'build_scheme' list item and the 'build_file' name. For
495 example, if 'build_file' is set to "Makefile", the template could be
496 Configurations/Makefile.tmpl or Configurations/unix-Makefile.tmpl.
497 In case both Configurations/unix-Makefile.tmpl and
498 Configurations/Makefile.tmpl are present, the former takes
501 The build-file template is processed with the perl module
502 Text::Template, using "{-" and "-}" as delimiters that enclose the
503 perl code fragments that generate configuration-dependent content.
504 Those perl fragments have access to all the hash variables from
507 The build-file template is expected to define at least the following
508 perl functions in a perl code fragment enclosed with "{-" and "-}".
509 They are all expected to return a string with the lines they produce.
511 generatesrc - function that produces build file lines to generate
512 a source file from some input.
514 It's called like this:
516 generatesrc(src => "PATH/TO/tobegenerated",
517 generator => [ "generatingfile", ... ]
518 generator_incs => [ "INCL/PATH", ... ]
519 generator_deps => [ "dep1", ... ]
520 generator => [ "generatingfile", ... ]
521 incs => [ "INCL/PATH", ... ],
522 deps => [ "dep1", ... ],
523 intent => one of "libs", "dso", "bin" );
525 'src' has the name of the file to be generated.
526 'generator' is the command or part of command to
527 generate the file, of which the first item is
528 expected to be the file to generate from.
529 generatesrc() is expected to analyse and figure out
530 exactly how to apply that file and how to capture
531 the result. 'generator_incs' and 'generator_deps'
532 are include directories and files that the generator
533 file itself depends on. 'incs' and 'deps' are
534 include directories and files that are used if $(CC)
535 is used as an intermediary step when generating the
536 end product (the file indicated by 'src'). 'intent'
537 indicates what the generated file is going to be
540 src2obj - function that produces build file lines to build an
541 object file from source files and associated data.
543 It's called like this:
545 src2obj(obj => "PATH/TO/objectfile",
546 srcs => [ "PATH/TO/sourcefile", ... ],
547 deps => [ "dep1", ... ],
548 incs => [ "INCL/PATH", ... ]
549 intent => one of "lib", "dso", "bin" );
551 'obj' has the intended object file with '.o'
552 extension, src2obj() is expected to change it to
553 something more suitable for the platform.
554 'srcs' has the list of source files to build the
555 object file, with the first item being the source
556 file that directly corresponds to the object file.
557 'deps' is a list of explicit dependencies. 'incs'
558 is a list of include file directories. Finally,
559 'intent' indicates what this object file is going
562 obj2lib - function that produces build file lines to build a
563 static library file ("libfoo.a" in Unix terms) from
568 obj2lib(lib => "PATH/TO/libfile",
569 objs => [ "PATH/TO/objectfile", ... ]);
571 'lib' has the intended library file name *without*
572 extension, obj2lib is expected to add that. 'objs'
573 has the list of object files to build this library.
575 libobj2shlib - backward compatibility function that's used the
576 same way as obj2shlib (described next), and was
577 expected to build the shared library from the
578 corresponding static library when that was suitable.
579 NOTE: building a shared library from a static
580 library is now DEPRECATED, as they no longer share
581 object files. Attempting to do this will fail.
583 obj2shlib - function that produces build file lines to build a
584 shareable object library file ("libfoo.so" in Unix
585 terms) from the corresponding object files.
589 obj2shlib(shlib => "PATH/TO/shlibfile",
590 lib => "PATH/TO/libfile",
591 objs => [ "PATH/TO/objectfile", ... ],
592 deps => [ "PATH/TO/otherlibfile", ... ]);
594 'lib' has the base (static) library ffile name
595 *without* extension. This is useful in case
596 supporting files are needed (such as import
597 libraries on Windows).
598 'shlib' has the corresponding shared library name
599 *without* extension. 'deps' has the list of other
600 libraries (also *without* extension) this library
601 needs to be linked with. 'objs' has the list of
602 object files to build this library.
604 obj2dso - function that produces build file lines to build a
605 dynamic shared object file from object files.
609 obj2dso(lib => "PATH/TO/libfile",
610 objs => [ "PATH/TO/objectfile", ... ],
611 deps => [ "PATH/TO/otherlibfile",
614 This is almost the same as obj2shlib, but the
615 intent is to build a shareable library that can be
616 loaded in runtime (a "plugin"...).
618 obj2bin - function that produces build file lines to build an
619 executable file from object files.
623 obj2bin(bin => "PATH/TO/binfile",
624 objs => [ "PATH/TO/objectfile", ... ],
625 deps => [ "PATH/TO/libfile", ... ]);
627 'bin' has the intended executable file name
628 *without* extension, obj2bin is expected to add
629 that. 'objs' has the list of object files to build
630 this library. 'deps' has the list of library files
631 (also *without* extension) that the programs needs
634 in2script - function that produces build file lines to build a
635 script file from some input.
639 in2script(script => "PATH/TO/scriptfile",
640 sources => [ "PATH/TO/infile", ... ]);
642 'script' has the intended script file name.
643 'sources' has the list of source files to build the
644 resulting script from.
646 In all cases, file file paths are relative to the build tree top, and
647 the build file actions run with the build tree top as current working
650 Make sure to end the section with these functions with a string that
651 you thing is appropriate for the resulting build file. If nothing
652 else, end it like this:
654 ""; # Make sure no lingering values end up in the Makefile
658 Configure helper scripts
659 ========================
661 Configure uses helper scripts in this directory:
666 These scripts are per platform family, to check the integrity of the
667 tools used for configuration and building. The checker script used is
668 either {build_platform}-{build_file}-checker.pm or
669 {build_platform}-checker.pm, where {build_platform} is the second
670 'build_scheme' list element from the configuration target data, and
671 {build_file} is 'build_file' from the same target data.
673 If the check succeeds, the script is expected to end with a non-zero
674 expression. If the check fails, the script can end with a zero, or