1 /* $OpenBSD: dso.h,v 1.13 2022/07/12 14:42:49 kn Exp $ */ 2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL 3 * project 2000. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2000 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing@OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@cryptsoft.com). 56 * 57 */ 58 59 #ifndef HEADER_DSO_H 60 #define HEADER_DSO_H 61 62 #include <openssl/crypto.h> 63 64 #ifdef __cplusplus 65 extern "C" { 66 #endif 67 68 /* These values are used as commands to DSO_ctrl() */ 69 #define DSO_CTRL_GET_FLAGS 1 70 #define DSO_CTRL_SET_FLAGS 2 71 #define DSO_CTRL_OR_FLAGS 3 72 73 /* By default, DSO_load() will translate the provided filename into a form 74 * typical for the platform (more specifically the DSO_METHOD) using the 75 * dso_name_converter function of the method. Eg. win32 will transform "blah" 76 * into "blah.dll", and dlfcn will transform it into "libblah.so". The 77 * behaviour can be overridden by setting the name_converter callback in the DSO 78 * object (using DSO_set_name_converter()). This callback could even utilise 79 * the DSO_METHOD's converter too if it only wants to override behaviour for 80 * one or two possible DSO methods. However, the following flag can be set in a 81 * DSO to prevent *any* native name-translation at all - eg. if the caller has 82 * prompted the user for a path to a driver library so the filename should be 83 * interpreted as-is. */ 84 #define DSO_FLAG_NO_NAME_TRANSLATION 0x01 85 /* An extra flag to give if only the extension should be added as 86 * translation. This is obviously only of importance on Unix and 87 * other operating systems where the translation also may prefix 88 * the name with something, like 'lib', and ignored everywhere else. 89 * This flag is also ignored if DSO_FLAG_NO_NAME_TRANSLATION is used 90 * at the same time. */ 91 #define DSO_FLAG_NAME_TRANSLATION_EXT_ONLY 0x02 92 93 /* The following flag controls the translation of symbol names to upper 94 * case. This is currently only being implemented for OpenVMS. 95 */ 96 #define DSO_FLAG_UPCASE_SYMBOL 0x10 97 98 /* This flag loads the library with public symbols. 99 * Meaning: The exported symbols of this library are public 100 * to all libraries loaded after this library. 101 * At the moment only implemented in unix. 102 */ 103 #define DSO_FLAG_GLOBAL_SYMBOLS 0x20 104 105 106 typedef void (*DSO_FUNC_TYPE)(void); 107 108 typedef struct dso_st DSO; 109 110 /* The function prototype used for method functions (or caller-provided 111 * callbacks) that transform filenames. They are passed a DSO structure pointer 112 * (or NULL if they are to be used independantly of a DSO object) and a 113 * filename to transform. They should either return NULL (if there is an error 114 * condition) or a newly allocated string containing the transformed form that 115 * the caller will need to free with free() when done. */ 116 typedef char* (*DSO_NAME_CONVERTER_FUNC)(DSO *, const char *); 117 /* The function prototype used for method functions (or caller-provided 118 * callbacks) that merge two file specifications. They are passed a 119 * DSO structure pointer (or NULL if they are to be used independantly of 120 * a DSO object) and two file specifications to merge. They should 121 * either return NULL (if there is an error condition) or a newly allocated 122 * string containing the result of merging that the caller will need 123 * to free with free() when done. 124 * Here, merging means that bits and pieces are taken from each of the 125 * file specifications and added together in whatever fashion that is 126 * sensible for the DSO method in question. The only rule that really 127 * applies is that if the two specification contain pieces of the same 128 * type, the copy from the first string takes priority. One could see 129 * it as the first specification is the one given by the user and the 130 * second being a bunch of defaults to add on if they're missing in the 131 * first. */ 132 typedef char* (*DSO_MERGER_FUNC)(DSO *, const char *, const char *); 133 134 typedef struct dso_meth_st { 135 const char *name; 136 /* Loads a shared library, NB: new DSO_METHODs must ensure that a 137 * successful load populates the loaded_filename field, and likewise a 138 * successful unload frees and NULLs it out. */ 139 int (*dso_load)(DSO *dso); 140 /* Unloads a shared library */ 141 int (*dso_unload)(DSO *dso); 142 /* Binds a variable */ 143 void *(*dso_bind_var)(DSO *dso, const char *symname); 144 /* Binds a function - assumes a return type of DSO_FUNC_TYPE. 145 * This should be cast to the real function prototype by the 146 * caller. Platforms that don't have compatible representations 147 * for different prototypes (this is possible within ANSI C) 148 * are highly unlikely to have shared libraries at all, let 149 * alone a DSO_METHOD implemented for them. */ 150 DSO_FUNC_TYPE (*dso_bind_func)(DSO *dso, const char *symname); 151 152 /* The generic (yuck) "ctrl()" function. NB: Negative return 153 * values (rather than zero) indicate errors. */ 154 long (*dso_ctrl)(DSO *dso, int cmd, long larg, void *parg); 155 /* The default DSO_METHOD-specific function for converting filenames to 156 * a canonical native form. */ 157 DSO_NAME_CONVERTER_FUNC dso_name_converter; 158 /* The default DSO_METHOD-specific function for converting filenames to 159 * a canonical native form. */ 160 DSO_MERGER_FUNC dso_merger; 161 162 /* [De]Initialisation handlers. */ 163 int (*init)(DSO *dso); 164 int (*finish)(DSO *dso); 165 166 /* Return pathname of the module containing location */ 167 int (*pathbyaddr)(void *addr, char *path, int sz); 168 /* Perform global symbol lookup, i.e. among *all* modules */ 169 void *(*globallookup)(const char *symname); 170 } DSO_METHOD; 171 172 /**********************************************************************/ 173 /* The low-level handle type used to refer to a loaded shared library */ 174 175 struct dso_st { 176 DSO_METHOD *meth; 177 /* Standard dlopen uses a (void *). Win32 uses a HANDLE. VMS 178 * doesn't use anything but will need to cache the filename 179 * for use in the dso_bind handler. All in all, let each 180 * method control its own destiny. "Handles" and such go in 181 * a STACK. */ 182 STACK_OF(void) *meth_data; 183 int references; 184 int flags; 185 /* For use by applications etc ... use this for your bits'n'pieces, 186 * don't touch meth_data! */ 187 CRYPTO_EX_DATA ex_data; 188 /* If this callback function pointer is set to non-NULL, then it will 189 * be used in DSO_load() in place of meth->dso_name_converter. NB: This 190 * should normally set using DSO_set_name_converter(). */ 191 DSO_NAME_CONVERTER_FUNC name_converter; 192 /* If this callback function pointer is set to non-NULL, then it will 193 * be used in DSO_load() in place of meth->dso_merger. NB: This 194 * should normally set using DSO_set_merger(). */ 195 DSO_MERGER_FUNC merger; 196 /* This is populated with (a copy of) the platform-independant 197 * filename used for this DSO. */ 198 char *filename; 199 /* This is populated with (a copy of) the translated filename by which 200 * the DSO was actually loaded. It is NULL iff the DSO is not currently 201 * loaded. NB: This is here because the filename translation process 202 * may involve a callback being invoked more than once not only to 203 * convert to a platform-specific form, but also to try different 204 * filenames in the process of trying to perform a load. As such, this 205 * variable can be used to indicate (a) whether this DSO structure 206 * corresponds to a loaded library or not, and (b) the filename with 207 * which it was actually loaded. */ 208 char *loaded_filename; 209 }; 210 211 212 DSO * DSO_new(void); 213 DSO * DSO_new_method(DSO_METHOD *method); 214 int DSO_free(DSO *dso); 215 int DSO_flags(DSO *dso); 216 int DSO_up_ref(DSO *dso); 217 long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg); 218 219 /* This function sets the DSO's name_converter callback. If it is non-NULL, 220 * then it will be used instead of the associated DSO_METHOD's function. If 221 * oldcb is non-NULL then it is set to the function pointer value being 222 * replaced. Return value is non-zero for success. */ 223 int DSO_set_name_converter(DSO *dso, DSO_NAME_CONVERTER_FUNC cb, 224 DSO_NAME_CONVERTER_FUNC *oldcb); 225 /* These functions can be used to get/set the platform-independant filename 226 * used for a DSO. NB: set will fail if the DSO is already loaded. */ 227 const char *DSO_get_filename(DSO *dso); 228 int DSO_set_filename(DSO *dso, const char *filename); 229 /* This function will invoke the DSO's name_converter callback to translate a 230 * filename, or if the callback isn't set it will instead use the DSO_METHOD's 231 * converter. If "filename" is NULL, the "filename" in the DSO itself will be 232 * used. If the DSO_FLAG_NO_NAME_TRANSLATION flag is set, then the filename is 233 * simply duplicated. NB: This function is usually called from within a 234 * DSO_METHOD during the processing of a DSO_load() call, and is exposed so that 235 * caller-created DSO_METHODs can do the same thing. A non-NULL return value 236 * will need to be free()'d. */ 237 char *DSO_convert_filename(DSO *dso, const char *filename); 238 /* This function will invoke the DSO's merger callback to merge two file 239 * specifications, or if the callback isn't set it will instead use the 240 * DSO_METHOD's merger. A non-NULL return value will need to be 241 * free()'d. */ 242 char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2); 243 /* If the DSO is currently loaded, this returns the filename that it was loaded 244 * under, otherwise it returns NULL. So it is also useful as a test as to 245 * whether the DSO is currently loaded. NB: This will not necessarily return 246 * the same value as DSO_convert_filename(dso, dso->filename), because the 247 * DSO_METHOD's load function may have tried a variety of filenames (with 248 * and/or without the aid of the converters) before settling on the one it 249 * actually loaded. */ 250 const char *DSO_get_loaded_filename(DSO *dso); 251 252 void DSO_set_default_method(DSO_METHOD *meth); 253 DSO_METHOD *DSO_get_default_method(void); 254 DSO_METHOD *DSO_get_method(DSO *dso); 255 DSO_METHOD *DSO_set_method(DSO *dso, DSO_METHOD *meth); 256 257 /* The all-singing all-dancing load function, you normally pass NULL 258 * for the first and third parameters. Use DSO_up and DSO_free for 259 * subsequent reference count handling. Any flags passed in will be set 260 * in the constructed DSO after its init() function but before the 261 * load operation. If 'dso' is non-NULL, 'flags' is ignored. */ 262 DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags); 263 264 /* This function binds to a variable inside a shared library. */ 265 void *DSO_bind_var(DSO *dso, const char *symname); 266 267 /* This function binds to a function inside a shared library. */ 268 DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname); 269 270 /* This method is the default, but will beg, borrow, or steal whatever 271 * method should be the default on any particular platform (including 272 * DSO_METH_null() if necessary). */ 273 DSO_METHOD *DSO_METHOD_openssl(void); 274 275 /* This method is defined for all platforms - if a platform has no 276 * DSO support then this will be the only method! */ 277 DSO_METHOD *DSO_METHOD_null(void); 278 279 /* If DSO_DLFCN is defined, the standard dlfcn.h-style functions 280 * (dlopen, dlclose, dlsym, etc) will be used and incorporated into 281 * this method. If not, this method will return NULL. */ 282 DSO_METHOD *DSO_METHOD_dlfcn(void); 283 284 /* This function writes null-terminated pathname of DSO module 285 * containing 'addr' into 'sz' large caller-provided 'path' and 286 * returns the number of characters [including trailing zero] 287 * written to it. If 'sz' is 0 or negative, 'path' is ignored and 288 * required amount of charachers [including trailing zero] to 289 * accommodate pathname is returned. If 'addr' is NULL, then 290 * pathname of cryptolib itself is returned. Negative or zero 291 * return value denotes error. 292 */ 293 int DSO_pathbyaddr(void *addr, char *path, int sz); 294 295 /* This function should be used with caution! It looks up symbols in 296 * *all* loaded modules and if module gets unloaded by somebody else 297 * attempt to dereference the pointer is doomed to have fatal 298 * consequences. Primary usage for this function is to probe *core* 299 * system functionality, e.g. check if getnameinfo(3) is available 300 * at run-time without bothering about OS-specific details such as 301 * libc.so.versioning or where does it actually reside: in libc 302 * itself or libsocket. */ 303 void *DSO_global_lookup(const char *name); 304 305 void ERR_load_DSO_strings(void); 306 307 /* Error codes for the DSO functions. */ 308 309 /* Function codes. */ 310 #define DSO_F_BEOS_BIND_FUNC 144 311 #define DSO_F_BEOS_BIND_VAR 145 312 #define DSO_F_BEOS_LOAD 146 313 #define DSO_F_BEOS_NAME_CONVERTER 147 314 #define DSO_F_BEOS_UNLOAD 148 315 #define DSO_F_DLFCN_BIND_FUNC 100 316 #define DSO_F_DLFCN_BIND_VAR 101 317 #define DSO_F_DLFCN_LOAD 102 318 #define DSO_F_DLFCN_MERGER 130 319 #define DSO_F_DLFCN_NAME_CONVERTER 123 320 #define DSO_F_DLFCN_UNLOAD 103 321 #define DSO_F_DL_BIND_FUNC 104 322 #define DSO_F_DL_BIND_VAR 105 323 #define DSO_F_DL_LOAD 106 324 #define DSO_F_DL_MERGER 131 325 #define DSO_F_DL_NAME_CONVERTER 124 326 #define DSO_F_DL_UNLOAD 107 327 #define DSO_F_DSO_BIND_FUNC 108 328 #define DSO_F_DSO_BIND_VAR 109 329 #define DSO_F_DSO_CONVERT_FILENAME 126 330 #define DSO_F_DSO_CTRL 110 331 #define DSO_F_DSO_FREE 111 332 #define DSO_F_DSO_GET_FILENAME 127 333 #define DSO_F_DSO_GET_LOADED_FILENAME 128 334 #define DSO_F_DSO_GLOBAL_LOOKUP 139 335 #define DSO_F_DSO_LOAD 112 336 #define DSO_F_DSO_MERGE 132 337 #define DSO_F_DSO_NEW_METHOD 113 338 #define DSO_F_DSO_PATHBYADDR 140 339 #define DSO_F_DSO_SET_FILENAME 129 340 #define DSO_F_DSO_SET_NAME_CONVERTER 122 341 #define DSO_F_DSO_UP_REF 114 342 #define DSO_F_GLOBAL_LOOKUP_FUNC 138 343 #define DSO_F_PATHBYADDR 137 344 #define DSO_F_VMS_BIND_SYM 115 345 #define DSO_F_VMS_LOAD 116 346 #define DSO_F_VMS_MERGER 133 347 #define DSO_F_VMS_UNLOAD 117 348 #define DSO_F_WIN32_BIND_FUNC 118 349 #define DSO_F_WIN32_BIND_VAR 119 350 #define DSO_F_WIN32_GLOBALLOOKUP 142 351 #define DSO_F_WIN32_GLOBALLOOKUP_FUNC 143 352 #define DSO_F_WIN32_JOINER 135 353 #define DSO_F_WIN32_LOAD 120 354 #define DSO_F_WIN32_MERGER 134 355 #define DSO_F_WIN32_NAME_CONVERTER 125 356 #define DSO_F_WIN32_PATHBYADDR 141 357 #define DSO_F_WIN32_SPLITTER 136 358 #define DSO_F_WIN32_UNLOAD 121 359 360 /* Reason codes. */ 361 #define DSO_R_CTRL_FAILED 100 362 #define DSO_R_DSO_ALREADY_LOADED 110 363 #define DSO_R_EMPTY_FILE_STRUCTURE 113 364 #define DSO_R_FAILURE 114 365 #define DSO_R_FILENAME_TOO_BIG 101 366 #define DSO_R_FINISH_FAILED 102 367 #define DSO_R_INCORRECT_FILE_SYNTAX 115 368 #define DSO_R_LOAD_FAILED 103 369 #define DSO_R_NAME_TRANSLATION_FAILED 109 370 #define DSO_R_NO_FILENAME 111 371 #define DSO_R_NO_FILE_SPECIFICATION 116 372 #define DSO_R_NULL_HANDLE 104 373 #define DSO_R_SET_FILENAME_FAILED 112 374 #define DSO_R_STACK_ERROR 105 375 #define DSO_R_SYM_FAILURE 106 376 #define DSO_R_UNLOAD_FAILED 107 377 #define DSO_R_UNSUPPORTED 108 378 379 #ifdef __cplusplus 380 } 381 #endif 382 #endif 383