LTKCPP-- LLRP Toolkit C Plus Plus Library
dso.h
00001 /* dso.h -*- mode:C; c-file-style: "eay" -*- */
00002 /*
00003  * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
00004  * 2000.
00005  */
00006 /* ====================================================================
00007  * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
00008  *
00009  * Redistribution and use in source and binary forms, with or without
00010  * modification, are permitted provided that the following conditions
00011  * are met:
00012  *
00013  * 1. Redistributions of source code must retain the above copyright
00014  *    notice, this list of conditions and the following disclaimer.
00015  *
00016  * 2. Redistributions in binary form must reproduce the above copyright
00017  *    notice, this list of conditions and the following disclaimer in
00018  *    the documentation and/or other materials provided with the
00019  *    distribution.
00020  *
00021  * 3. All advertising materials mentioning features or use of this
00022  *    software must display the following acknowledgment:
00023  *    "This product includes software developed by the OpenSSL Project
00024  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
00025  *
00026  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
00027  *    endorse or promote products derived from this software without
00028  *    prior written permission. For written permission, please contact
00029  *    licensing@OpenSSL.org.
00030  *
00031  * 5. Products derived from this software may not be called "OpenSSL"
00032  *    nor may "OpenSSL" appear in their names without prior written
00033  *    permission of the OpenSSL Project.
00034  *
00035  * 6. Redistributions of any form whatsoever must retain the following
00036  *    acknowledgment:
00037  *    "This product includes software developed by the OpenSSL Project
00038  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
00039  *
00040  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
00041  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00042  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
00043  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
00044  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
00045  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
00046  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00047  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
00048  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
00049  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
00050  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
00051  * OF THE POSSIBILITY OF SUCH DAMAGE.
00052  * ====================================================================
00053  *
00054  * This product includes cryptographic software written by Eric Young
00055  * (eay@cryptsoft.com).  This product includes software written by Tim
00056  * Hudson (tjh@cryptsoft.com).
00057  *
00058  */
00059 
00060 #ifndef HEADER_DSO_H
00061 # define HEADER_DSO_H
00062 
00063 # include <openssl/crypto.h>
00064 
00065 #ifdef __cplusplus
00066 extern "C" {
00067 #endif
00068 
00069 /* These values are used as commands to DSO_ctrl() */
00070 # define DSO_CTRL_GET_FLAGS      1
00071 # define DSO_CTRL_SET_FLAGS      2
00072 # define DSO_CTRL_OR_FLAGS       3
00073 
00074 /*
00075  * By default, DSO_load() will translate the provided filename into a form
00076  * typical for the platform (more specifically the DSO_METHOD) using the
00077  * dso_name_converter function of the method. Eg. win32 will transform "blah"
00078  * into "blah.dll", and dlfcn will transform it into "libblah.so". The
00079  * behaviour can be overriden by setting the name_converter callback in the
00080  * DSO object (using DSO_set_name_converter()). This callback could even
00081  * utilise the DSO_METHOD's converter too if it only wants to override
00082  * behaviour for one or two possible DSO methods. However, the following flag
00083  * can be set in a DSO to prevent *any* native name-translation at all - eg.
00084  * if the caller has prompted the user for a path to a driver library so the
00085  * filename should be interpreted as-is.
00086  */
00087 # define DSO_FLAG_NO_NAME_TRANSLATION            0x01
00088 /*
00089  * An extra flag to give if only the extension should be added as
00090  * translation.  This is obviously only of importance on Unix and other
00091  * operating systems where the translation also may prefix the name with
00092  * something, like 'lib', and ignored everywhere else. This flag is also
00093  * ignored if DSO_FLAG_NO_NAME_TRANSLATION is used at the same time.
00094  */
00095 # define DSO_FLAG_NAME_TRANSLATION_EXT_ONLY      0x02
00096 
00097 /*
00098  * The following flag controls the translation of symbol names to upper case.
00099  * This is currently only being implemented for OpenVMS.
00100  */
00101 # define DSO_FLAG_UPCASE_SYMBOL                  0x10
00102 
00103 /*
00104  * This flag loads the library with public symbols. Meaning: The exported
00105  * symbols of this library are public to all libraries loaded after this
00106  * library. At the moment only implemented in unix.
00107  */
00108 # define DSO_FLAG_GLOBAL_SYMBOLS                 0x20
00109 
00110 typedef void (*DSO_FUNC_TYPE) (void);
00111 
00112 typedef struct dso_st DSO;
00113 
00114 /*
00115  * The function prototype used for method functions (or caller-provided
00116  * callbacks) that transform filenames. They are passed a DSO structure
00117  * pointer (or NULL if they are to be used independantly of a DSO object) and
00118  * a filename to transform. They should either return NULL (if there is an
00119  * error condition) or a newly allocated string containing the transformed
00120  * form that the caller will need to free with OPENSSL_free() when done.
00121  */
00122 typedef char *(*DSO_NAME_CONVERTER_FUNC)(DSO *, const char *);
00123 /*
00124  * The function prototype used for method functions (or caller-provided
00125  * callbacks) that merge two file specifications. They are passed a DSO
00126  * structure pointer (or NULL if they are to be used independantly of a DSO
00127  * object) and two file specifications to merge. They should either return
00128  * NULL (if there is an error condition) or a newly allocated string
00129  * containing the result of merging that the caller will need to free with
00130  * OPENSSL_free() when done. Here, merging means that bits and pieces are
00131  * taken from each of the file specifications and added together in whatever
00132  * fashion that is sensible for the DSO method in question.  The only rule
00133  * that really applies is that if the two specification contain pieces of the
00134  * same type, the copy from the first string takes priority.  One could see
00135  * it as the first specification is the one given by the user and the second
00136  * being a bunch of defaults to add on if they're missing in the first.
00137  */
00138 typedef char *(*DSO_MERGER_FUNC)(DSO *, const char *, const char *);
00139 
00140 typedef struct dso_meth_st {
00141     const char *name;
00142     /*
00143      * Loads a shared library, NB: new DSO_METHODs must ensure that a
00144      * successful load populates the loaded_filename field, and likewise a
00145      * successful unload OPENSSL_frees and NULLs it out.
00146      */
00147     int (*dso_load) (DSO *dso);
00148     /* Unloads a shared library */
00149     int (*dso_unload) (DSO *dso);
00150     /* Binds a variable */
00151     void *(*dso_bind_var) (DSO *dso, const char *symname);
00152     /*
00153      * Binds a function - assumes a return type of DSO_FUNC_TYPE. This should
00154      * be cast to the real function prototype by the caller. Platforms that
00155      * don't have compatible representations for different prototypes (this
00156      * is possible within ANSI C) are highly unlikely to have shared
00157      * libraries at all, let alone a DSO_METHOD implemented for them.
00158      */
00159     DSO_FUNC_TYPE (*dso_bind_func) (DSO *dso, const char *symname);
00160 /* I don't think this would actually be used in any circumstances. */
00161 # if 0
00162     /* Unbinds a variable */
00163     int (*dso_unbind_var) (DSO *dso, char *symname, void *symptr);
00164     /* Unbinds a function */
00165     int (*dso_unbind_func) (DSO *dso, char *symname, DSO_FUNC_TYPE symptr);
00166 # endif
00167     /*
00168      * The generic (yuck) "ctrl()" function. NB: Negative return values
00169      * (rather than zero) indicate errors.
00170      */
00171     long (*dso_ctrl) (DSO *dso, int cmd, long larg, void *parg);
00172     /*
00173      * The default DSO_METHOD-specific function for converting filenames to a
00174      * canonical native form.
00175      */
00176     DSO_NAME_CONVERTER_FUNC dso_name_converter;
00177     /*
00178      * The default DSO_METHOD-specific function for converting filenames to a
00179      * canonical native form.
00180      */
00181     DSO_MERGER_FUNC dso_merger;
00182     /* [De]Initialisation handlers. */
00183     int (*init) (DSO *dso);
00184     int (*finish) (DSO *dso);
00185     /* Return pathname of the module containing location */
00186     int (*pathbyaddr) (void *addr, char *path, int sz);
00187     /* Perform global symbol lookup, i.e. among *all* modules */
00188     void *(*globallookup) (const char *symname);
00189 } DSO_METHOD;
00190 
00191 /**********************************************************************/
00192 /* The low-level handle type used to refer to a loaded shared library */
00193 
00194 struct dso_st {
00195     DSO_METHOD *meth;
00196     /*
00197      * Standard dlopen uses a (void *). Win32 uses a HANDLE. VMS doesn't use
00198      * anything but will need to cache the filename for use in the dso_bind
00199      * handler. All in all, let each method control its own destiny.
00200      * "Handles" and such go in a STACK.
00201      */
00202     STACK_OF(void) *meth_data;
00203     int references;
00204     int flags;
00205     /*
00206      * For use by applications etc ... use this for your bits'n'pieces, don't
00207      * touch meth_data!
00208      */
00209     CRYPTO_EX_DATA ex_data;
00210     /*
00211      * If this callback function pointer is set to non-NULL, then it will be
00212      * used in DSO_load() in place of meth->dso_name_converter. NB: This
00213      * should normally set using DSO_set_name_converter().
00214      */
00215     DSO_NAME_CONVERTER_FUNC name_converter;
00216     /*
00217      * If this callback function pointer is set to non-NULL, then it will be
00218      * used in DSO_load() in place of meth->dso_merger. NB: This should
00219      * normally set using DSO_set_merger().
00220      */
00221     DSO_MERGER_FUNC merger;
00222     /*
00223      * This is populated with (a copy of) the platform-independant filename
00224      * used for this DSO.
00225      */
00226     char *filename;
00227     /*
00228      * This is populated with (a copy of) the translated filename by which
00229      * the DSO was actually loaded. It is NULL iff the DSO is not currently
00230      * loaded. NB: This is here because the filename translation process may
00231      * involve a callback being invoked more than once not only to convert to
00232      * a platform-specific form, but also to try different filenames in the
00233      * process of trying to perform a load. As such, this variable can be
00234      * used to indicate (a) whether this DSO structure corresponds to a
00235      * loaded library or not, and (b) the filename with which it was actually
00236      * loaded.
00237      */
00238     char *loaded_filename;
00239 };
00240 
00241 DSO *DSO_new(void);
00242 DSO *DSO_new_method(DSO_METHOD *method);
00243 int DSO_free(DSO *dso);
00244 int DSO_flags(DSO *dso);
00245 int DSO_up_ref(DSO *dso);
00246 long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg);
00247 
00248 /*
00249  * This function sets the DSO's name_converter callback. If it is non-NULL,
00250  * then it will be used instead of the associated DSO_METHOD's function. If
00251  * oldcb is non-NULL then it is set to the function pointer value being
00252  * replaced. Return value is non-zero for success.
00253  */
00254 int DSO_set_name_converter(DSO *dso, DSO_NAME_CONVERTER_FUNC cb,
00255                            DSO_NAME_CONVERTER_FUNC *oldcb);
00256 /*
00257  * These functions can be used to get/set the platform-independant filename
00258  * used for a DSO. NB: set will fail if the DSO is already loaded.
00259  */
00260 const char *DSO_get_filename(DSO *dso);
00261 int DSO_set_filename(DSO *dso, const char *filename);
00262 /*
00263  * This function will invoke the DSO's name_converter callback to translate a
00264  * filename, or if the callback isn't set it will instead use the DSO_METHOD's
00265  * converter. If "filename" is NULL, the "filename" in the DSO itself will be
00266  * used. If the DSO_FLAG_NO_NAME_TRANSLATION flag is set, then the filename is
00267  * simply duplicated. NB: This function is usually called from within a
00268  * DSO_METHOD during the processing of a DSO_load() call, and is exposed so
00269  * that caller-created DSO_METHODs can do the same thing. A non-NULL return
00270  * value will need to be OPENSSL_free()'d.
00271  */
00272 char *DSO_convert_filename(DSO *dso, const char *filename);
00273 /*
00274  * This function will invoke the DSO's merger callback to merge two file
00275  * specifications, or if the callback isn't set it will instead use the
00276  * DSO_METHOD's merger.  A non-NULL return value will need to be
00277  * OPENSSL_free()'d.
00278  */
00279 char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2);
00280 /*
00281  * If the DSO is currently loaded, this returns the filename that it was
00282  * loaded under, otherwise it returns NULL. So it is also useful as a test as
00283  * to whether the DSO is currently loaded. NB: This will not necessarily
00284  * return the same value as DSO_convert_filename(dso, dso->filename), because
00285  * the DSO_METHOD's load function may have tried a variety of filenames (with
00286  * and/or without the aid of the converters) before settling on the one it
00287  * actually loaded.
00288  */
00289 const char *DSO_get_loaded_filename(DSO *dso);
00290 
00291 void DSO_set_default_method(DSO_METHOD *meth);
00292 DSO_METHOD *DSO_get_default_method(void);
00293 DSO_METHOD *DSO_get_method(DSO *dso);
00294 DSO_METHOD *DSO_set_method(DSO *dso, DSO_METHOD *meth);
00295 
00296 /*
00297  * The all-singing all-dancing load function, you normally pass NULL for the
00298  * first and third parameters. Use DSO_up and DSO_free for subsequent
00299  * reference count handling. Any flags passed in will be set in the
00300  * constructed DSO after its init() function but before the load operation.
00301  * If 'dso' is non-NULL, 'flags' is ignored.
00302  */
00303 DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags);
00304 
00305 /* This function binds to a variable inside a shared library. */
00306 void *DSO_bind_var(DSO *dso, const char *symname);
00307 
00308 /* This function binds to a function inside a shared library. */
00309 DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname);
00310 
00311 /*
00312  * This method is the default, but will beg, borrow, or steal whatever method
00313  * should be the default on any particular platform (including
00314  * DSO_METH_null() if necessary).
00315  */
00316 DSO_METHOD *DSO_METHOD_openssl(void);
00317 
00318 /*
00319  * This method is defined for all platforms - if a platform has no DSO
00320  * support then this will be the only method!
00321  */
00322 DSO_METHOD *DSO_METHOD_null(void);
00323 
00324 /*
00325  * If DSO_DLFCN is defined, the standard dlfcn.h-style functions (dlopen,
00326  * dlclose, dlsym, etc) will be used and incorporated into this method. If
00327  * not, this method will return NULL.
00328  */
00329 DSO_METHOD *DSO_METHOD_dlfcn(void);
00330 
00331 /*
00332  * If DSO_DL is defined, the standard dl.h-style functions (shl_load,
00333  * shl_unload, shl_findsym, etc) will be used and incorporated into this
00334  * method. If not, this method will return NULL.
00335  */
00336 DSO_METHOD *DSO_METHOD_dl(void);
00337 
00338 /* If WIN32 is defined, use DLLs. If not, return NULL. */
00339 DSO_METHOD *DSO_METHOD_win32(void);
00340 
00341 /* If VMS is defined, use shared images. If not, return NULL. */
00342 DSO_METHOD *DSO_METHOD_vms(void);
00343 
00344 /*
00345  * This function writes null-terminated pathname of DSO module containing
00346  * 'addr' into 'sz' large caller-provided 'path' and returns the number of
00347  * characters [including trailing zero] written to it. If 'sz' is 0 or
00348  * negative, 'path' is ignored and required amount of charachers [including
00349  * trailing zero] to accomodate pathname is returned. If 'addr' is NULL, then
00350  * pathname of cryptolib itself is returned. Negative or zero return value
00351  * denotes error.
00352  */
00353 int DSO_pathbyaddr(void *addr, char *path, int sz);
00354 
00355 /*
00356  * This function should be used with caution! It looks up symbols in *all*
00357  * loaded modules and if module gets unloaded by somebody else attempt to
00358  * dereference the pointer is doomed to have fatal consequences. Primary
00359  * usage for this function is to probe *core* system functionality, e.g.
00360  * check if getnameinfo(3) is available at run-time without bothering about
00361  * OS-specific details such as libc.so.versioning or where does it actually
00362  * reside: in libc itself or libsocket.
00363  */
00364 void *DSO_global_lookup(const char *name);
00365 
00366 /* If BeOS is defined, use shared images. If not, return NULL. */
00367 DSO_METHOD *DSO_METHOD_beos(void);
00368 
00369 /* BEGIN ERROR CODES */
00370 /*
00371  * The following lines are auto generated by the script mkerr.pl. Any changes
00372  * made after this point may be overwritten when the script is next run.
00373  */
00374 void ERR_load_DSO_strings(void);
00375 
00376 /* Error codes for the DSO functions. */
00377 
00378 /* Function codes. */
00379 # define DSO_F_BEOS_BIND_FUNC                             144
00380 # define DSO_F_BEOS_BIND_VAR                              145
00381 # define DSO_F_BEOS_LOAD                                  146
00382 # define DSO_F_BEOS_NAME_CONVERTER                        147
00383 # define DSO_F_BEOS_UNLOAD                                148
00384 # define DSO_F_DLFCN_BIND_FUNC                            100
00385 # define DSO_F_DLFCN_BIND_VAR                             101
00386 # define DSO_F_DLFCN_LOAD                                 102
00387 # define DSO_F_DLFCN_MERGER                               130
00388 # define DSO_F_DLFCN_NAME_CONVERTER                       123
00389 # define DSO_F_DLFCN_UNLOAD                               103
00390 # define DSO_F_DL_BIND_FUNC                               104
00391 # define DSO_F_DL_BIND_VAR                                105
00392 # define DSO_F_DL_LOAD                                    106
00393 # define DSO_F_DL_MERGER                                  131
00394 # define DSO_F_DL_NAME_CONVERTER                          124
00395 # define DSO_F_DL_UNLOAD                                  107
00396 # define DSO_F_DSO_BIND_FUNC                              108
00397 # define DSO_F_DSO_BIND_VAR                               109
00398 # define DSO_F_DSO_CONVERT_FILENAME                       126
00399 # define DSO_F_DSO_CTRL                                   110
00400 # define DSO_F_DSO_FREE                                   111
00401 # define DSO_F_DSO_GET_FILENAME                           127
00402 # define DSO_F_DSO_GET_LOADED_FILENAME                    128
00403 # define DSO_F_DSO_GLOBAL_LOOKUP                          139
00404 # define DSO_F_DSO_LOAD                                   112
00405 # define DSO_F_DSO_MERGE                                  132
00406 # define DSO_F_DSO_NEW_METHOD                             113
00407 # define DSO_F_DSO_PATHBYADDR                             140
00408 # define DSO_F_DSO_SET_FILENAME                           129
00409 # define DSO_F_DSO_SET_NAME_CONVERTER                     122
00410 # define DSO_F_DSO_UP_REF                                 114
00411 # define DSO_F_GLOBAL_LOOKUP_FUNC                         138
00412 # define DSO_F_PATHBYADDR                                 137
00413 # define DSO_F_VMS_BIND_SYM                               115
00414 # define DSO_F_VMS_LOAD                                   116
00415 # define DSO_F_VMS_MERGER                                 133
00416 # define DSO_F_VMS_UNLOAD                                 117
00417 # define DSO_F_WIN32_BIND_FUNC                            118
00418 # define DSO_F_WIN32_BIND_VAR                             119
00419 # define DSO_F_WIN32_GLOBALLOOKUP                         142
00420 # define DSO_F_WIN32_GLOBALLOOKUP_FUNC                    143
00421 # define DSO_F_WIN32_JOINER                               135
00422 # define DSO_F_WIN32_LOAD                                 120
00423 # define DSO_F_WIN32_MERGER                               134
00424 # define DSO_F_WIN32_NAME_CONVERTER                       125
00425 # define DSO_F_WIN32_PATHBYADDR                           141
00426 # define DSO_F_WIN32_SPLITTER                             136
00427 # define DSO_F_WIN32_UNLOAD                               121
00428 
00429 /* Reason codes. */
00430 # define DSO_R_CTRL_FAILED                                100
00431 # define DSO_R_DSO_ALREADY_LOADED                         110
00432 # define DSO_R_EMPTY_FILE_STRUCTURE                       113
00433 # define DSO_R_FAILURE                                    114
00434 # define DSO_R_FILENAME_TOO_BIG                           101
00435 # define DSO_R_FINISH_FAILED                              102
00436 # define DSO_R_INCORRECT_FILE_SYNTAX                      115
00437 # define DSO_R_LOAD_FAILED                                103
00438 # define DSO_R_NAME_TRANSLATION_FAILED                    109
00439 # define DSO_R_NO_FILENAME                                111
00440 # define DSO_R_NO_FILE_SPECIFICATION                      116
00441 # define DSO_R_NULL_HANDLE                                104
00442 # define DSO_R_SET_FILENAME_FAILED                        112
00443 # define DSO_R_STACK_ERROR                                105
00444 # define DSO_R_SYM_FAILURE                                106
00445 # define DSO_R_UNLOAD_FAILED                              107
00446 # define DSO_R_UNSUPPORTED                                108
00447 
00448 #ifdef  __cplusplus
00449 }
00450 #endif
00451 #endif