dso.h revision 656d9c7f52f88b3a3daccafa7655dec086c4756e
1/* dso.h -*- mode:C; c-file-style: "eay" -*- */ 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 65extern "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/* 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 106typedef void (*DSO_FUNC_TYPE)(void); 107 108typedef 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 OPENSSL_free() when done. */ 116typedef 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 OPENSSL_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. */ 132typedef char* (*DSO_MERGER_FUNC)(DSO *, const char *, const char *); 133 134typedef struct dso_meth_st 135 { 136 const char *name; 137 /* Loads a shared library, NB: new DSO_METHODs must ensure that a 138 * successful load populates the loaded_filename field, and likewise a 139 * successful unload OPENSSL_frees and NULLs it out. */ 140 int (*dso_load)(DSO *dso); 141 /* Unloads a shared library */ 142 int (*dso_unload)(DSO *dso); 143 /* Binds a variable */ 144 void *(*dso_bind_var)(DSO *dso, const char *symname); 145 /* Binds a function - assumes a return type of DSO_FUNC_TYPE. 146 * This should be cast to the real function prototype by the 147 * caller. Platforms that don't have compatible representations 148 * for different prototypes (this is possible within ANSI C) 149 * are highly unlikely to have shared libraries at all, let 150 * alone a DSO_METHOD implemented for them. */ 151 DSO_FUNC_TYPE (*dso_bind_func)(DSO *dso, const char *symname); 152 153/* I don't think this would actually be used in any circumstances. */ 154#if 0 155 /* Unbinds a variable */ 156 int (*dso_unbind_var)(DSO *dso, char *symname, void *symptr); 157 /* Unbinds a function */ 158 int (*dso_unbind_func)(DSO *dso, char *symname, DSO_FUNC_TYPE symptr); 159#endif 160 /* The generic (yuck) "ctrl()" function. NB: Negative return 161 * values (rather than zero) indicate errors. */ 162 long (*dso_ctrl)(DSO *dso, int cmd, long larg, void *parg); 163 /* The default DSO_METHOD-specific function for converting filenames to 164 * a canonical native form. */ 165 DSO_NAME_CONVERTER_FUNC dso_name_converter; 166 /* The default DSO_METHOD-specific function for converting filenames to 167 * a canonical native form. */ 168 DSO_MERGER_FUNC dso_merger; 169 170 /* [De]Initialisation handlers. */ 171 int (*init)(DSO *dso); 172 int (*finish)(DSO *dso); 173 } DSO_METHOD; 174 175/**********************************************************************/ 176/* The low-level handle type used to refer to a loaded shared library */ 177 178struct dso_st 179 { 180 DSO_METHOD *meth; 181 /* Standard dlopen uses a (void *). Win32 uses a HANDLE. VMS 182 * doesn't use anything but will need to cache the filename 183 * for use in the dso_bind handler. All in all, let each 184 * method control its own destiny. "Handles" and such go in 185 * a STACK. */ 186 STACK *meth_data; 187 int references; 188 int flags; 189 /* For use by applications etc ... use this for your bits'n'pieces, 190 * don't touch meth_data! */ 191 CRYPTO_EX_DATA ex_data; 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_name_converter. NB: This 194 * should normally set using DSO_set_name_converter(). */ 195 DSO_NAME_CONVERTER_FUNC name_converter; 196 /* If this callback function pointer is set to non-NULL, then it will 197 * be used in DSO_load() in place of meth->dso_merger. NB: This 198 * should normally set using DSO_set_merger(). */ 199 DSO_MERGER_FUNC merger; 200 /* This is populated with (a copy of) the platform-independant 201 * filename used for this DSO. */ 202 char *filename; 203 /* This is populated with (a copy of) the translated filename by which 204 * the DSO was actually loaded. It is NULL iff the DSO is not currently 205 * loaded. NB: This is here because the filename translation process 206 * may involve a callback being invoked more than once not only to 207 * convert to a platform-specific form, but also to try different 208 * filenames in the process of trying to perform a load. As such, this 209 * variable can be used to indicate (a) whether this DSO structure 210 * corresponds to a loaded library or not, and (b) the filename with 211 * which it was actually loaded. */ 212 char *loaded_filename; 213 }; 214 215 216DSO * DSO_new(void); 217DSO * DSO_new_method(DSO_METHOD *method); 218int DSO_free(DSO *dso); 219int DSO_flags(DSO *dso); 220int DSO_up_ref(DSO *dso); 221long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg); 222 223/* This function sets the DSO's name_converter callback. If it is non-NULL, 224 * then it will be used instead of the associated DSO_METHOD's function. If 225 * oldcb is non-NULL then it is set to the function pointer value being 226 * replaced. Return value is non-zero for success. */ 227int DSO_set_name_converter(DSO *dso, DSO_NAME_CONVERTER_FUNC cb, 228 DSO_NAME_CONVERTER_FUNC *oldcb); 229/* These functions can be used to get/set the platform-independant filename 230 * used for a DSO. NB: set will fail if the DSO is already loaded. */ 231const char *DSO_get_filename(DSO *dso); 232int DSO_set_filename(DSO *dso, const char *filename); 233/* This function will invoke the DSO's name_converter callback to translate a 234 * filename, or if the callback isn't set it will instead use the DSO_METHOD's 235 * converter. If "filename" is NULL, the "filename" in the DSO itself will be 236 * used. If the DSO_FLAG_NO_NAME_TRANSLATION flag is set, then the filename is 237 * simply duplicated. NB: This function is usually called from within a 238 * DSO_METHOD during the processing of a DSO_load() call, and is exposed so that 239 * caller-created DSO_METHODs can do the same thing. A non-NULL return value 240 * will need to be OPENSSL_free()'d. */ 241char *DSO_convert_filename(DSO *dso, const char *filename); 242/* This function will invoke the DSO's merger callback to merge two file 243 * specifications, or if the callback isn't set it will instead use the 244 * DSO_METHOD's merger. A non-NULL return value will need to be 245 * OPENSSL_free()'d. */ 246char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2); 247/* If the DSO is currently loaded, this returns the filename that it was loaded 248 * under, otherwise it returns NULL. So it is also useful as a test as to 249 * whether the DSO is currently loaded. NB: This will not necessarily return 250 * the same value as DSO_convert_filename(dso, dso->filename), because the 251 * DSO_METHOD's load function may have tried a variety of filenames (with 252 * and/or without the aid of the converters) before settling on the one it 253 * actually loaded. */ 254const char *DSO_get_loaded_filename(DSO *dso); 255 256void DSO_set_default_method(DSO_METHOD *meth); 257DSO_METHOD *DSO_get_default_method(void); 258DSO_METHOD *DSO_get_method(DSO *dso); 259DSO_METHOD *DSO_set_method(DSO *dso, DSO_METHOD *meth); 260 261/* The all-singing all-dancing load function, you normally pass NULL 262 * for the first and third parameters. Use DSO_up and DSO_free for 263 * subsequent reference count handling. Any flags passed in will be set 264 * in the constructed DSO after its init() function but before the 265 * load operation. If 'dso' is non-NULL, 'flags' is ignored. */ 266DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags); 267 268/* This function binds to a variable inside a shared library. */ 269void *DSO_bind_var(DSO *dso, const char *symname); 270 271/* This function binds to a function inside a shared library. */ 272DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname); 273 274/* This method is the default, but will beg, borrow, or steal whatever 275 * method should be the default on any particular platform (including 276 * DSO_METH_null() if necessary). */ 277DSO_METHOD *DSO_METHOD_openssl(void); 278 279/* This method is defined for all platforms - if a platform has no 280 * DSO support then this will be the only method! */ 281DSO_METHOD *DSO_METHOD_null(void); 282 283/* If DSO_DLFCN is defined, the standard dlfcn.h-style functions 284 * (dlopen, dlclose, dlsym, etc) will be used and incorporated into 285 * this method. If not, this method will return NULL. */ 286DSO_METHOD *DSO_METHOD_dlfcn(void); 287 288/* If DSO_DL is defined, the standard dl.h-style functions (shl_load, 289 * shl_unload, shl_findsym, etc) will be used and incorporated into 290 * this method. If not, this method will return NULL. */ 291DSO_METHOD *DSO_METHOD_dl(void); 292 293/* If WIN32 is defined, use DLLs. If not, return NULL. */ 294DSO_METHOD *DSO_METHOD_win32(void); 295 296/* If VMS is defined, use shared images. If not, return NULL. */ 297DSO_METHOD *DSO_METHOD_vms(void); 298 299/* BEGIN ERROR CODES */ 300/* The following lines are auto generated by the script mkerr.pl. Any changes 301 * made after this point may be overwritten when the script is next run. 302 */ 303void ERR_load_DSO_strings(void); 304 305/* Error codes for the DSO functions. */ 306 307/* Function codes. */ 308#define DSO_F_DLFCN_BIND_FUNC 100 309#define DSO_F_DLFCN_BIND_VAR 101 310#define DSO_F_DLFCN_LOAD 102 311#define DSO_F_DLFCN_MERGER 130 312#define DSO_F_DLFCN_NAME_CONVERTER 123 313#define DSO_F_DLFCN_UNLOAD 103 314#define DSO_F_DL_BIND_FUNC 104 315#define DSO_F_DL_BIND_VAR 105 316#define DSO_F_DL_LOAD 106 317#define DSO_F_DL_MERGER 131 318#define DSO_F_DL_NAME_CONVERTER 124 319#define DSO_F_DL_UNLOAD 107 320#define DSO_F_DSO_BIND_FUNC 108 321#define DSO_F_DSO_BIND_VAR 109 322#define DSO_F_DSO_CONVERT_FILENAME 126 323#define DSO_F_DSO_CTRL 110 324#define DSO_F_DSO_FREE 111 325#define DSO_F_DSO_GET_FILENAME 127 326#define DSO_F_DSO_GET_LOADED_FILENAME 128 327#define DSO_F_DSO_LOAD 112 328#define DSO_F_DSO_MERGE 132 329#define DSO_F_DSO_NEW_METHOD 113 330#define DSO_F_DSO_SET_FILENAME 129 331#define DSO_F_DSO_SET_NAME_CONVERTER 122 332#define DSO_F_DSO_UP_REF 114 333#define DSO_F_VMS_BIND_SYM 115 334#define DSO_F_VMS_LOAD 116 335#define DSO_F_VMS_MERGER 133 336#define DSO_F_VMS_UNLOAD 117 337#define DSO_F_WIN32_BIND_FUNC 118 338#define DSO_F_WIN32_BIND_VAR 119 339#define DSO_F_WIN32_JOINER 135 340#define DSO_F_WIN32_LOAD 120 341#define DSO_F_WIN32_MERGER 134 342#define DSO_F_WIN32_NAME_CONVERTER 125 343#define DSO_F_WIN32_SPLITTER 136 344#define DSO_F_WIN32_UNLOAD 121 345 346/* Reason codes. */ 347#define DSO_R_CTRL_FAILED 100 348#define DSO_R_DSO_ALREADY_LOADED 110 349#define DSO_R_EMPTY_FILE_STRUCTURE 113 350#define DSO_R_FAILURE 114 351#define DSO_R_FILENAME_TOO_BIG 101 352#define DSO_R_FINISH_FAILED 102 353#define DSO_R_INCORRECT_FILE_SYNTAX 115 354#define DSO_R_LOAD_FAILED 103 355#define DSO_R_NAME_TRANSLATION_FAILED 109 356#define DSO_R_NO_FILENAME 111 357#define DSO_R_NO_FILE_SPECIFICATION 116 358#define DSO_R_NULL_HANDLE 104 359#define DSO_R_SET_FILENAME_FAILED 112 360#define DSO_R_STACK_ERROR 105 361#define DSO_R_SYM_FAILURE 106 362#define DSO_R_UNLOAD_FAILED 107 363#define DSO_R_UNSUPPORTED 108 364 365#ifdef __cplusplus 366} 367#endif 368#endif 369