Configurations/README

   1 Configurations of OpenSSL target platforms
   2 ==========================================
   3
   4 Target configurations are a collection of facts that we know about
   5 different platforms and their capabilities.  We organise them in a
   6 hash table, where each entry represent a specific target.
   7
   8 In each table entry, the following keys are significant:
   9
  10         inherit_from    => Other targets to inherit values from.
  11                            Explained further below. [1]
  12         template        => Set to 1 if this isn't really a platform
  13                            target.  Instead, this target is a template
  14                            upon which other targets can be built.
  15                            Explained further below.  [1]
  16
  17         sys_id          => System identity for systems where that
  18                            is difficult to determine automatically.
  19
  20         cc              => The compiler command, usually one of "cc",
  21                            "gcc" or "clang".  This command is normally
  22                            also used to link object files and
  23                            libraries into the final program.
  24         cflags          => Flags that are used at all times when
  25                            compiling.
  26         defines         => As an alternative, macro definitions may be
  27                            present here instead of in `cflags'.  If
  28                            given here, they MUST be as an array of the
  29                            string such as "MACRO=value", or just
  30                            "MACRO" for definitions without value.
  31         shared_cflag    => Extra compilation flags used when
  32                            compiling for shared libraries, typically
  33                            something like "-fPIC".
  34
  35         (linking is a complex thing, see [3] below)
  36         ld              => Linker command, usually not defined
  37                            (meaning the compiler command is used
  38                            instead).
  39                            (NOTE: this is here for future use, it's
  40                            not implemented yet)
  41         lflags          => Flags that are used when linking apps.
  42         shared_ldflag   => Flags that are used when linking shared
  43                            or dynamic libraries.
  44         plib_lflags     => Extra linking flags to appear just before
  45                            the libraries on the command line.
  46         ex_libs         => Extra libraries that are needed when
  47                            linking.
  48
  49         ar              => The library archive command, the default is
  50                            "ar".
  51                            (NOTE: this is here for future use, it's
  52                            not implemented yet)
  53         arflags         => Flags to be used with the library archive
  54                            command.
  55
  56         ranlib          => The library archive indexing command, the
  57                            default is 'ranlib' it it exists.
  58
  59         unistd          => An alternative header to the typical
  60                            '<unistd.h>'.  This is very rarely needed.
  61
  62         shared_extension => File name extension used for shared
  63                             libraries.
  64         obj_extension   => File name extension used for object files.
  65                            On unix, this defaults to ".o" (NOTE: this
  66                            is here for future use, it's not
  67                            implemented yet)
  68         exe_extension   => File name extension used for executable
  69                            files.  On unix, this defaults to "" (NOTE:
  70                            this is here for future use, it's not
  71                            implemented yet)
  72
  73         thread_scheme   => The type of threads is used on the
  74                            configured platform.  Currently known
  75                            values are "(unknown)", "pthreads",
  76                            "uithreads" (a.k.a solaris threads) and
  77                            "winthreads".  Except for "(unknown)", the
  78                            actual value is currently ignored but may
  79                            be used in the future.  See further notes
  80                            below [2].
  81         dso_scheme      => The type of dynamic shared objects to build
  82                            for.  This mostly comes into play with
  83                            engines, but can be used for other purposes
  84                            as well.  Valid values are "DLFCN"
  85                            (dlopen() et al), "DLFCN_NO_H" (for systems
  86                            that use dlopen() et al but do not have
  87                            fcntl.h), "DL" (shl_load() et al), "WIN32"
  88                            and "VMS".
  89         perlasm_scheme  => The perlasm method used to created the
  90                            assembler files used when compiling with
  91                            assembler implementations.
  92         shared_target   => The shared library building method used.
  93                            This is a target found in Makefile.shared.
  94         build_scheme    => The scheme used to build up a Makefile.
  95                            In its simplest form, the value is a string
  96                            with the name of the build scheme.
  97                            The value may also take the form of a list
  98                            of strings, if the build_scheme is to have
  99                            some options.  In this case, the first
 100                            string in the list is the name of the build
 101                            scheme.
 102                            Currently recognised build schemes are
 103                            "mk1mf" and "unixmake" and "unified".
 104                            For the "unified" build scheme, this item
 105                            *must* be an array with the first being the
 106                            word "unified" and the second being a word
 107                            to identify the platform family.
 108
 109         multilib        => On systems that support having multiple
 110                            implementations of a library (typically a
 111                            32-bit and a 64-bit variant), this is used
 112                            to have the different variants in different
 113                            directories.
 114
 115         bn_ops          => Building options (was just bignum options
 116                            in the earlier history of this option,
 117                            hence the name).  This a string of words
 118                            that describe properties on the designated
 119                            target platform, such as the type of
 120                            integers used to build up the bitnum,
 121                            different ways to implement certain ciphers
 122                            and so on.  To fully comprehend the
 123                            meaning, the best is to read the affected
 124                            source.
 125                            The valid words are:
 126
 127                            BN_LLONG     use 'unsigned long long' in
 128                                         some bignum calculations.
 129                                         This has no value when
 130                                         SIXTY_FOUR_BIT or
 131                                         SIXTY_FOUR_BIT_LONG is given.
 132                            RC4_CHAR     makes the basic RC4 unit of
 133                                         calculation an unsigned char.
 134                            SIXTY_FOUR_BIT       processor registers
 135                                                 are 64 bits, long is
 136                                                 32 bits, long long is
 137                                                 64 bits.
 138                            SIXTY_FOUR_BIT_LONG  processor registers
 139                                                 are 64 bits, long is
 140                                                 64 bits.
 141                            THIRTY_TWO_BIT       processor registers
 142                                                 are 32 bits.
 143                            EXPORT_VAR_AS_FN     for shared libraries,
 144                                                 export vars as
 145                                                 accessor functions.
 146
 147         apps_extra_src  => Extra source to build apps/openssl, as
 148                            needed by the target.
 149         cpuid_asm_src   => assembler implementation of cpuid code as
 150                            well as OPENSSL_cleanse().
 151                            Default to mem_clr.c
 152         bn_asm_src      => Assembler implementation of core bignum
 153                            functions.
 154                            Defaults to bn_asm.c
 155         ec_asm_src      => Assembler implementation of core EC
 156                            functions.
 157         des_asm_src     => Assembler implementation of core DES
 158                            encryption functions.
 159                            Defaults to 'des_enc.c fcrypt_b.c'
 160         aes_asm_src     => Assembler implementation of core AES
 161                            functions.
 162                            Defaults to 'aes_core.c aes_cbc.c'
 163         bf_asm_src      => Assembler implementation of core BlowFish
 164                            functions.
 165                            Defaults to 'bf_enc.c'
 166         md5_asm_src     => Assembler implementation of core MD5
 167                            functions.
 168         sha1_asm_src    => Assembler implementation of core SHA1,
 169                            functions, and also possibly SHA256 and
 170                            SHA512 ones.
 171         cast_asm_src    => Assembler implementation of core CAST
 172                            functions.
 173                            Defaults to 'c_enc.c'
 174         rc4_asm_src     => Assembler implementation of core RC4
 175                            functions.
 176                            Defaults to 'rc4_enc.c rc4_skey.c'
 177         rmd160_asm_src  => Assembler implementation of core RMD160
 178                            functions.
 179         rc5_asm_src     => Assembler implementation of core RC5
 180                            functions.
 181                            Defaults to 'rc5_enc.c'
 182         wp_asm_src      => Assembler implementation of core WHIRLPOOL
 183                            functions.
 184         cmll_asm_src    => Assembler implementation of core CAMELLIA
 185                            functions.
 186                            Defaults to 'camellia.c cmll_misc.c cmll_cbc.c'
 187         modes_asm_src   => Assembler implementation of cipher modes,
 188                            currently the functions gcm_gmult_4bit and
 189                            gcm_ghash_4bit.
 190         padlock_asm_src => Assembler implementation of core parts of
 191                            the padlock engine.  This is mandatory on
 192                            any platform where the padlock engine might
 193                            actually be built.
 194
 195
 196 [1] as part of the target configuration, one can have a key called
 197     'inherit_from' that indicate what other configurations to inherit
 198     data from.  These are resolved recursively.
 199
 200     Inheritance works as a set of default values that can be overridden
 201     by corresponding key values in the inheriting configuration.
 202
 203     Note 1: any configuration table can be used as a template.
 204     Note 2: pure templates have the attribute 'template => 1' and
 205             cannot be used as build targets.
 206
 207     If several configurations are given in the 'inherit_from' array,
 208     the values of same attribute are concatenated with space
 209     separation.  With this, it's possible to have several smaller
 210     templates for different configuration aspects that can be combined
 211     into a complete configuration.
 212
 213     instead of a scalar value or an array, a value can be a code block
 214     of the form 'sub { /* your code here */ }'.  This code block will
 215     be called with the list of inherited values for that key as
 216     arguments.  In fact, the concatenation of strings is really done
 217     by using 'sub { join(" ",@_) }' on the list of inherited values.
 218
 219     An example:
 220
 221         "foo" => {
 222                 template => 1,
 223                 haha => "ha ha",
 224                 hoho => "ho",
 225                 ignored => "This should not appear in the end result",
 226         },
 227         "bar" => {
 228                 template => 1,
 229                 haha => "ah",
 230                 hoho => "haho",
 231                 hehe => "hehe"
 232         },
 233         "laughter" => {
 234                 inherit_from => [ "foo", "bar" ],
 235                 hehe => sub { join(" ",(@_,"!!!")) },
 236                 ignored => "",
 237         }
 238
 239         The entry for "laughter" will become as follows after processing:
 240
 241         "laughter" => {
 242                 haha => "ha ha ah",
 243                 hoho => "ho haho",
 244                 hehe => "hehe !!!",
 245                 ignored => ""
 246         }
 247
 248 [2] OpenSSL is built with threading capabilities unless the user
 249     specifies 'no-threads'.  The value of the key 'thread_scheme' may
 250     be "(unknown)", in which case the user MUST give some compilation
 251     flags to Configure.
 252
 253 [3] OpenSSL has three types of things to link from object files or
 254     static libraries:
 255
 256     - shared libraries; that would be libcrypto and libssl.
 257     - shared objects (sometimes called dynamic libraries);  that would
 258       be the engines.
 259     - applications; those are apps/openssl and all the test apps.
 260
 261     Very roughly speaking, linking is done like this (words in braces
 262     represent the configuration settings documented at the beginning
 263     of this file):
 264
 265     shared libraries:
 266         {ld} $(CFLAGS) {shared_ldflag} -shared -o libfoo.so \
 267             -Wl,--whole-archive libfoo.a -Wl,--no-whole-archive \
 268             {plib_lflags} -lcrypto {ex_libs}
 269
 270     shared objects:
 271         {ld} $(CFLAGS) {shared_ldflag} -shared -o libeng.so \
 272             blah1.o blah2.o {plib_lflags} -lcrypto {ex_libs}
 273
 274     applications:
 275         {ld} $(CFLAGS) {lflags} -o app \
 276             app1.o utils.o {plib_lflags} -lssl -lcrypto {ex_libs}
 277
 278
 279 Historically, the target configurations came in form of a string with
 280 values separated by colons.  This use is deprecated.  The string form
 281 looked like this:
 282
 283    "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}"
 284
 285
 286 Build info files
 287 ================
 288
 289 The build.info files that are spread over the source tree contain the
 290 minimum information needed to build and distribute OpenSSL.  It uses a
 291 simple and yet fairly powerful language to determine what needs to be
 292 built, from what sources, and other relationships between files.
 293
 294 For every build.info file, all file references are relative to the
 295 directory of the build.info file for source files, and the
 296 corresponding build directory for built files if the build tree
 297 differs from the source tree.
 298
 299 When processed, every line is processed with the perl module
 300 Text::Template, using the delimiters "{-" and "-}".  The hashes
 301 %config and %target are passed to the perl fragments, along with
 302 $sourcedir and $builddir, which are the locations of the source
 303 directory for the current build.info file and the corresponding build
 304 directory, all relative to the top of the build tree.
 305
 306 To begin with, things to be built are declared by setting specific
 307 variables:
 308
 309     PROGRAMS=foo bar
 310     LIBS=libsomething
 311     ENGINES=libeng
 312     SCRIPTS=myhack
 313     EXTRA=file1 file2
 314
 315 Note that the files mentioned for PROGRAMS, LIBS and ENGINES *must* be
 316 without extensions.  The build file templates will figure them out.
 317
 318 For each thing to be built, it is then possible to say what sources
 319 they are built from:
 320
 321     PROGRAMS=foo bar
 322     SOURCE[foo]=foo.c common.c
 323     SOURCE[bar]=bar.c extra.c common.c
 324
 325 It's also possible to tell some other dependencies:
 326
 327     DEPEND[foo]=libsomething
 328     DEPEND[libbar]=libsomethingelse
 329
 330 (it could be argued that 'libsomething' and 'libsomethingelse' are
 331 source as well.  However, the files given through SOURCE are expected
 332 to be located in the source tree while files given through DEPEND are
 333 expected to be located in the build tree)
 334
 335 For some libraries, we maintain files with public symbols and their
 336 slot in a transfer vector (important on some platforms).  It can be
 337 declared like this:
 338
 339     ORDINALS[libcrypto]=crypto
 340
 341 The value is not the name of the file in question, but rather the
 342 argument to util/mkdef.pl that indicates which file to use.
 343
 344 One some platforms, shared libraries come with a name that's different
 345 from their static counterpart.  That's declared as follows:
 346
 347     SHARED_NAME[libfoo]=cygfoo-{- $config{shlibver} -}
 348
 349 The example is from Cygwin, which has a required naming convention.
 350
 351 Sometimes, it makes sense to rename an output file, for example a
 352 library:
 353
 354     RENAME[libfoo]=libbar
 355
 356 That lines has "libfoo" get renamed to "libbar".  While it makes no
 357 sense at all to just have a rename like that (why not just use
 358 "libbar" everywhere?), it does make sense when it can be used
 359 conditionally.  See a little further below for an example.
 360
 361 For any file to be built, it's also possible to tell what extra
 362 include paths the build of their source files should use:
 363
 364     INCLUDE[foo]=include
 365
 366 In some cases, one might want to generate some source files from
 367 others, that's done as follows:
 368
 369     GENERATE[foo.s]=asm/something.pl $(CFLAGS)
 370     GENERATE[bar.s]=asm/bar.S
 371
 372 The value of each GENERATE line is a command line or part of it.
 373 Configure places no rules on the command line, except the the first
 374 item muct be the generator file.  It is, however, entirely up to the
 375 build file template to define exactly how those command lines should
 376 be handled, how the output is captured and so on.
 377
 378 NOTE: GENERATE lines are limited to one command only per GENERATE.
 379
 380 As a last resort, it's possible to have raw build file lines, between
 381 BEGINRAW and ENDRAW lines as follows:
 382
 383     BEGINRAW[Makefile(unix)]
 384     haha.h: {- $builddir -}/Makefile
 385         echo "/* haha */" > haha.h
 386     ENDRAW[Makefile(unix)]
 387
 388 The word withing square brackets is the build_file configuration item
 389 or the build_file configuration item followed by the second word in the
 390 build_scheme configuration item for the configured target within
 391 parenthesis as shown above.  For example, with the following relevant
 392 configuration items:
 393
 394    build_file   => "build.ninja"
 395    build_scheme => [ "unified", "unix" ]
 396
 397 ... these lines will be considered:
 398
 399    BEGINRAW[build.ninja]
 400    build haha.h: echo "/* haha */" > haha.h
 401    ENDRAW[build.ninja]
 402
 403    BEGINRAW[build.ninja(unix)]
 404    build hoho.h: echo "/* hoho */" > hoho.h
 405    ENDRAW[build.ninja(unix)]
 406
 407 Should it be needed because the recipes within a RAW section might
 408 clash with those generated by Configure, it's possible to tell it
 409 not to generate them with the use of OVERRIDES, for example:
 410
 411     SOURCE[libfoo]=foo.c bar.c
 412
 413     OVERRIDES=bar.o
 414     BEGINRAW[Makefile(unix)]
 415     bar.o: bar.c
 416         $(CC) $(CFLAGS) -DSPECIAL -c -o $@ $<
 417     ENDRAW[Makefile(unix)]
 418
 419 See the documentation further up for more information on configuration
 420 items.
 421
 422 Finally, you can have some simple conditional use of the build.info
 423 information, looking like this:
 424
 425     IF[1]
 426      something
 427     ELSIF[2]
 428      something other
 429     ELSE
 430      something else
 431     ENDIF
 432
 433 The expression in square brackets is interpreted as a string in perl,
 434 and will be seen as true if perl thinks it is, otherwise false.  For
 435 example, the above would have "something" used, since 1 is true.
 436
 437 Together with the use of Text::Template, this can be used as
 438 conditions based on something in the passed variables, for example:
 439
 440     IF[{- $disabled{shared} -}]
 441       LIBS=libcrypto
 442       SOURCE[libcrypto]=...
 443     ELSE
 444       LIBS=libfoo
 445       SOURCE[libfoo]=...
 446     ENDIF
 447
 448 or:
 449
 450     # VMS has a cultural standard where all libraries are prefixed.
 451     # For OpenSSL, the choice is 'ossl_'
 452     IF[{- $config{target} =~ /^vms/ -}]
 453      RENAME[libcrypto]=ossl_libcrypto
 454      RENAME[libssl]=ossl_libssl
 455     ENDIF
 456
 457
 458 Build-file programming with the "unified" build system
 459 ======================================================
 460
 461 "Build files" are called "Makefile" on Unix-like operating systems,
 462 "descrip.mms" for MMS on VMS, "makefile" for nmake on Windows, etc.
 463
 464 To use the "unified" build system, the target configuration needs to
 465 set the three items 'build_scheme', 'build_file' and 'build_command'.
 466 In the rest of this section, we will assume that 'build_scheme' is set
 467 to "unified" (see the configurations documentation above for the
 468 details).
 469
 470 For any name given by 'build_file', the "unified" system expects a
 471 template file in Configurations/ named like the build file, with
 472 ".tmpl" appended, or in case of possible ambiguity, a combination of
 473 the second 'build_scheme' list item and the 'build_file' name.  For
 474 example, if 'build_file' is set to "Makefile", the template could be
 475 Configurations/Makefile.tmpl or Configurations/unix-Makefile.tmpl.
 476 In case both Configurations/unix-Makefile.tmpl and
 477 Configurations/Makefile.tmpl are present, the former takes
 478 precedence.
 479
 480 The build-file template is processed with the perl module
 481 Text::Template, using "{-" and "-}" as delimiters that enclose the
 482 perl code fragments that generate configuration-dependent content.
 483 Those perl fragments have access to all the hash variables from
 484 configdata.pem.
 485
 486 The build-file template is expected to define at least the following
 487 perl functions in a perl code fragment enclosed with "{-" and "-}".
 488 They are all expected to return a string with the lines they produce.
 489
 490     generatesrc - function that produces build file lines to generate
 491                   a source file from some input.
 492
 493                   It's called like this:
 494
 495                         generatesrc(src => "PATH/TO/tobegenerated",
 496                                     generator => [ "generatingfile", ... ]
 497                                     deps => [ "dep1", ... ],
 498                                     intent => one of "libs", "dso", "bin" );
 499
 500                   'src' has the name of the file to be generated.
 501                   'generator' is the command or part of command to
 502                   generate the file, of which the first item is
 503                   expected to be the file to generate from.
 504                   generatesrc() is expected to analyse and figure out
 505                   exactly how to apply that file and how to capture
 506                   the result.  'deps' is a list of explicit
 507                   dependencies.  'intent' indicates what the generated
 508                   file is going to be used for.
 509
 510     src2obj     - function that produces build file lines to build an
 511                   object file from source files and associated data.
 512
 513                   It's called like this:
 514
 515                         src2obj(obj => "PATH/TO/objectfile",
 516                                 srcs => [ "PATH/TO/sourcefile", ... ],
 517                                 deps => [ "dep1", ... ],
 518                                 incs => [ "INCL/PATH", ... ]
 519                                 intent => one of "lib", "dso", "bin" );
 520
 521                   'obj' has the intended object file *without*
 522                   extension, src2obj() is expected to add that.
 523                   'srcs' has the list of source files to build the
 524                   object file, with the first item being the source
 525                   file that directly corresponds to the object file.
 526                   'deps' is a list of explicit dependencies.  'incs'
 527                   is a list of include file directories.  Finally,
 528                   'intent' indicates what this object file is going
 529                   to be used for.
 530
 531     obj2lib     - function that produces build file lines to build a
 532                   static library file ("libfoo.a" in Unix terms) from
 533                   object files.
 534
 535                   called like this:
 536
 537                         obj2lib(lib => "PATH/TO/libfile",
 538                                 objs => [ "PATH/TO/objectfile", ... ]);
 539
 540                   'lib' has the intended library file name *without*
 541                   extension, obj2lib is expected to add that.  'objs'
 542                   has the list of object files (also *without*
 543                   extension) to build this library.
 544
 545     libobj2shlib - function that produces build file lines to build a
 546                   shareable object library file ("libfoo.so" in Unix
 547                   terms) from the corresponding static library file
 548                   or object files.
 549
 550                   called like this:
 551
 552                         libobj2shlib(shlib => "PATH/TO/shlibfile",
 553                                      lib => "PATH/TO/libfile",
 554                                      objs => [ "PATH/TO/objectfile", ... ],
 555                                      deps => [ "PATH/TO/otherlibfile", ... ],
 556                                      ordinals => [ "word", "/PATH/TO/ordfile" ]);
 557
 558                   'lib' has the intended library file name *without*
 559                   extension, libobj2shlib is expected to add that.
 560                   'shlib' has the corresponding shared library name
 561                   *without* extension.  'deps' has the list of other
 562                   libraries (also *without* extension) this library
 563                   needs to be linked with.  'objs' has the list of
 564                   object files (also *without* extension) to build
 565                   this library.  'ordinals' MAY be present, and when
 566                   it is, its value is an array where the word is
 567                   "crypto" or "ssl" and the file is one of the ordinal
 568                   files util/libeay.num or util/ssleay.num in the
 569                   source directory.
 570
 571                   This function has a choice; it can use the
 572                   corresponding static library as input to make the
 573                   shared library, or the list of object files.
 574
 575     obj2dso     - function that produces build file lines to build a
 576                   dynamic shared object file from object files.
 577
 578                   called like this:
 579
 580                         obj2dso(lib => "PATH/TO/libfile",
 581                                 objs => [ "PATH/TO/objectfile", ... ],
 582                                 deps => [ "PATH/TO/otherlibfile",
 583                                 ... ]);
 584
 585                   This is almost the same as libobj2shlib, but the
 586                   intent is to build a shareable library that can be
 587                   loaded in runtime (a "plugin"...).  The differences
 588                   are subtle, one of the most visible ones is that the
 589                   resulting shareable library is produced from object
 590                   files only.
 591
 592     obj2bin     - function that produces build file lines to build an
 593                   executable file from object files.
 594
 595                   called like this:
 596
 597                         obj2bin(bin => "PATH/TO/binfile",
 598                                 objs => [ "PATH/TO/objectfile", ... ],
 599                                 deps => [ "PATH/TO/libfile", ... ]);
 600
 601                   'bin' has the intended executable file name
 602                   *without* extension, obj2bin is expected to add
 603                   that.  'objs' has the list of object files (also
 604                   *without* extension) to build this library.  'deps'
 605                   has the list of library files (also *without*
 606                   extension) that the programs needs to be linked
 607                   with.
 608
 609     in2script   - function that produces build file lines to build a
 610                   script file from some input.
 611
 612                   called like this:
 613
 614                         in2script(script => "PATH/TO/scriptfile",
 615                                   sources => [ "PATH/TO/infile", ... ]);
 616
 617                   'script' has the intended script file name.
 618                   'sources' has the list of source files to build the
 619                   resulting script from.
 620
 621 In all cases, file file paths are relative to the build tree top, and
 622 the build file actions run with the build tree top as current working
 623 directory.
 624
 625 Make sure to end the section with these functions with a string that
 626 you thing is appropriate for the resulting build file.  If nothing
 627 else, end it like this:
 628
 629       "";       # Make sure no lingering values end up in the Makefile
 630     -}