1 /* dso.h */ 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 overriden 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 99 typedef void (*DSO_FUNC_TYPE)(void); 100 101 typedef struct dso_st DSO; 102 103 /* The function prototype used for method functions (or caller-provided 104 * callbacks) that transform filenames. They are passed a DSO structure pointer 105 * (or NULL if they are to be used independantly of a DSO object) and a 106 * filename to transform. They should either return NULL (if there is an error 107 * condition) or a newly allocated string containing the transformed form that 108 * the caller will need to free with OPENSSL_free() when done. */ 109 typedef char* (*DSO_NAME_CONVERTER_FUNC)(DSO *, const char *); 110 111 typedef struct dso_meth_st 112 { 113 const char *name; 114 /* Loads a shared library, NB: new DSO_METHODs must ensure that a 115 * successful load populates the loaded_filename field, and likewise a 116 * successful unload OPENSSL_frees and NULLs it out. */ 117 int (*dso_load)(DSO *dso); 118 /* Unloads a shared library */ 119 int (*dso_unload)(DSO *dso); 120 /* Binds a variable */ 121 void *(*dso_bind_var)(DSO *dso, const char *symname); 122 /* Binds a function - assumes a return type of DSO_FUNC_TYPE. 123 * This should be cast to the real function prototype by the 124 * caller. Platforms that don't have compatible representations 125 * for different prototypes (this is possible within ANSI C) 126 * are highly unlikely to have shared libraries at all, let 127 * alone a DSO_METHOD implemented for them. */ 128 DSO_FUNC_TYPE (*dso_bind_func)(DSO *dso, const char *symname); 129 130 /* I don't think this would actually be used in any circumstances. */ 131 #if 0 132 /* Unbinds a variable */ 133 int (*dso_unbind_var)(DSO *dso, char *symname, void *symptr); 134 /* Unbinds a function */ 135 int (*dso_unbind_func)(DSO *dso, char *symname, DSO_FUNC_TYPE symptr); 136 #endif 137 /* The generic (yuck) "ctrl()" function. NB: Negative return 138 * values (rather than zero) indicate errors. */ 139 long (*dso_ctrl)(DSO *dso, int cmd, long larg, void *parg); 140 /* The default DSO_METHOD-specific function for converting filenames to 141 * a canonical native form. */ 142 DSO_NAME_CONVERTER_FUNC dso_name_converter; 143 144 /* [De]Initialisation handlers. */ 145 int (*init)(DSO *dso); 146 int (*finish)(DSO *dso); 147 } DSO_METHOD; 148 149 /**********************************************************************/ 150 /* The low-level handle type used to refer to a loaded shared library */ 151 152 struct dso_st 153 { 154 DSO_METHOD *meth; 155 /* Standard dlopen uses a (void *). Win32 uses a HANDLE. VMS 156 * doesn't use anything but will need to cache the filename 157 * for use in the dso_bind handler. All in all, let each 158 * method control its own destiny. "Handles" and such go in 159 * a STACK. */ 160 STACK *meth_data; 161 int references; 162 int flags; 163 /* For use by applications etc ... use this for your bits'n'pieces, 164 * don't touch meth_data! */ 165 CRYPTO_EX_DATA ex_data; 166 /* If this callback function pointer is set to non-NULL, then it will 167 * be used on DSO_load() in place of meth->dso_name_converter. NB: This 168 * should normally set using DSO_set_name_converter(). */ 169 DSO_NAME_CONVERTER_FUNC name_converter; 170 /* This is populated with (a copy of) the platform-independant 171 * filename used for this DSO. */ 172 char *filename; 173 /* This is populated with (a copy of) the translated filename by which 174 * the DSO was actually loaded. It is NULL iff the DSO is not currently 175 * loaded. NB: This is here because the filename translation process 176 * may involve a callback being invoked more than once not only to 177 * convert to a platform-specific form, but also to try different 178 * filenames in the process of trying to perform a load. As such, this 179 * variable can be used to indicate (a) whether this DSO structure 180 * corresponds to a loaded library or not, and (b) the filename with 181 * which it was actually loaded. */ 182 char *loaded_filename; 183 }; 184 185 186 DSO * DSO_new(void); 187 DSO * DSO_new_method(DSO_METHOD *method); 188 int DSO_free(DSO *dso); 189 int DSO_flags(DSO *dso); 190 int DSO_up_ref(DSO *dso); 191 long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg); 192 193 /* This function sets the DSO's name_converter callback. If it is non-NULL, 194 * then it will be used instead of the associated DSO_METHOD's function. If 195 * oldcb is non-NULL then it is set to the function pointer value being 196 * replaced. Return value is non-zero for success. */ 197 int DSO_set_name_converter(DSO *dso, DSO_NAME_CONVERTER_FUNC cb, 198 DSO_NAME_CONVERTER_FUNC *oldcb); 199 /* These functions can be used to get/set the platform-independant filename 200 * used for a DSO. NB: set will fail if the DSO is already loaded. */ 201 const char *DSO_get_filename(DSO *dso); 202 int DSO_set_filename(DSO *dso, const char *filename); 203 /* This function will invoke the DSO's name_converter callback to translate a 204 * filename, or if the callback isn't set it will instead use the DSO_METHOD's 205 * converter. If "filename" is NULL, the "filename" in the DSO itself will be 206 * used. If the DSO_FLAG_NO_NAME_TRANSLATION flag is set, then the filename is 207 * simply duplicated. NB: This function is usually called from within a 208 * DSO_METHOD during the processing of a DSO_load() call, and is exposed so that 209 * caller-created DSO_METHODs can do the same thing. A non-NULL return value 210 * will need to be OPENSSL_free()'d. */ 211 char *DSO_convert_filename(DSO *dso, const char *filename); 212 /* If the DSO is currently loaded, this returns the filename that it was loaded 213 * under, otherwise it returns NULL. So it is also useful as a test as to 214 * whether the DSO is currently loaded. NB: This will not necessarily return 215 * the same value as DSO_convert_filename(dso, dso->filename), because the 216 * DSO_METHOD's load function may have tried a variety of filenames (with 217 * and/or without the aid of the converters) before settling on the one it 218 * actually loaded. */ 219 const char *DSO_get_loaded_filename(DSO *dso); 220 221 void DSO_set_default_method(DSO_METHOD *meth); 222 DSO_METHOD *DSO_get_default_method(void); 223 DSO_METHOD *DSO_get_method(DSO *dso); 224 DSO_METHOD *DSO_set_method(DSO *dso, DSO_METHOD *meth); 225 226 /* The all-singing all-dancing load function, you normally pass NULL 227 * for the first and third parameters. Use DSO_up and DSO_free for 228 * subsequent reference count handling. Any flags passed in will be set 229 * in the constructed DSO after its init() function but before the 230 * load operation. If 'dso' is non-NULL, 'flags' is ignored. */ 231 DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags); 232 233 /* This function binds to a variable inside a shared library. */ 234 void *DSO_bind_var(DSO *dso, const char *symname); 235 236 /* This function binds to a function inside a shared library. */ 237 DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname); 238 239 /* This method is the default, but will beg, borrow, or steal whatever 240 * method should be the default on any particular platform (including 241 * DSO_METH_null() if necessary). */ 242 DSO_METHOD *DSO_METHOD_openssl(void); 243 244 /* This method is defined for all platforms - if a platform has no 245 * DSO support then this will be the only method! */ 246 DSO_METHOD *DSO_METHOD_null(void); 247 248 /* If DSO_DLFCN is defined, the standard dlfcn.h-style functions 249 * (dlopen, dlclose, dlsym, etc) will be used and incorporated into 250 * this method. If not, this method will return NULL. */ 251 DSO_METHOD *DSO_METHOD_dlfcn(void); 252 253 /* If DSO_DL is defined, the standard dl.h-style functions (shl_load, 254 * shl_unload, shl_findsym, etc) will be used and incorporated into 255 * this method. If not, this method will return NULL. */ 256 DSO_METHOD *DSO_METHOD_dl(void); 257 258 /* If WIN32 is defined, use DLLs. If not, return NULL. */ 259 DSO_METHOD *DSO_METHOD_win32(void); 260 261 /* If VMS is defined, use shared images. If not, return NULL. */ 262 DSO_METHOD *DSO_METHOD_vms(void); 263 264 /* BEGIN ERROR CODES */ 265 /* The following lines are auto generated by the script mkerr.pl. Any changes 266 * made after this point may be overwritten when the script is next run. 267 */ 268 void ERR_load_DSO_strings(void); 269 270 /* Error codes for the DSO functions. */ 271 272 /* Function codes. */ 273 #define DSO_F_DLFCN_BIND_FUNC 100 274 #define DSO_F_DLFCN_BIND_VAR 101 275 #define DSO_F_DLFCN_LOAD 102 276 #define DSO_F_DLFCN_NAME_CONVERTER 123 277 #define DSO_F_DLFCN_UNLOAD 103 278 #define DSO_F_DL_BIND_FUNC 104 279 #define DSO_F_DL_BIND_VAR 105 280 #define DSO_F_DL_LOAD 106 281 #define DSO_F_DL_NAME_CONVERTER 124 282 #define DSO_F_DL_UNLOAD 107 283 #define DSO_F_DSO_BIND_FUNC 108 284 #define DSO_F_DSO_BIND_VAR 109 285 #define DSO_F_DSO_CONVERT_FILENAME 126 286 #define DSO_F_DSO_CTRL 110 287 #define DSO_F_DSO_FREE 111 288 #define DSO_F_DSO_GET_FILENAME 127 289 #define DSO_F_DSO_GET_LOADED_FILENAME 128 290 #define DSO_F_DSO_LOAD 112 291 #define DSO_F_DSO_NEW_METHOD 113 292 #define DSO_F_DSO_SET_FILENAME 129 293 #define DSO_F_DSO_SET_NAME_CONVERTER 122 294 #define DSO_F_DSO_UP_REF 114 295 #define DSO_F_VMS_BIND_VAR 115 296 #define DSO_F_VMS_LOAD 116 297 #define DSO_F_VMS_UNLOAD 117 298 #define DSO_F_WIN32_BIND_FUNC 118 299 #define DSO_F_WIN32_BIND_VAR 119 300 #define DSO_F_WIN32_LOAD 120 301 #define DSO_F_WIN32_NAME_CONVERTER 125 302 #define DSO_F_WIN32_UNLOAD 121 303 304 /* Reason codes. */ 305 #define DSO_R_CTRL_FAILED 100 306 #define DSO_R_DSO_ALREADY_LOADED 110 307 #define DSO_R_FILENAME_TOO_BIG 101 308 #define DSO_R_FINISH_FAILED 102 309 #define DSO_R_LOAD_FAILED 103 310 #define DSO_R_NAME_TRANSLATION_FAILED 109 311 #define DSO_R_NO_FILENAME 111 312 #define DSO_R_NULL_HANDLE 104 313 #define DSO_R_SET_FILENAME_FAILED 112 314 #define DSO_R_STACK_ERROR 105 315 #define DSO_R_SYM_FAILURE 106 316 #define DSO_R_UNLOAD_FAILED 107 317 #define DSO_R_UNSUPPORTED 108 318 319 #ifdef __cplusplus 320 } 321 #endif 322 #endif 323