1 /* 2 * Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #ifndef HEADER_DSO_H 11 # define HEADER_DSO_H 12 13 # include <openssl/crypto.h> 14 15 #ifdef __cplusplus 16 extern "C" { 17 #endif 18 19 /* These values are used as commands to DSO_ctrl() */ 20 # define DSO_CTRL_GET_FLAGS 1 21 # define DSO_CTRL_SET_FLAGS 2 22 # define DSO_CTRL_OR_FLAGS 3 23 24 /* 25 * By default, DSO_load() will translate the provided filename into a form 26 * typical for the platform using the dso_name_converter function of the 27 * method. Eg. win32 will transform "blah" into "blah.dll", and dlfcn will 28 * transform it into "libblah.so". This callback could even utilise the 29 * DSO_METHOD's converter too if it only wants to override behaviour for 30 * one or two possible DSO methods. However, the following flag can be 31 * set in a DSO to prevent *any* native name-translation at all - eg. if 32 * the caller has prompted the user for a path to a driver library so the 33 * filename should be interpreted as-is. 34 */ 35 # define DSO_FLAG_NO_NAME_TRANSLATION 0x01 36 /* 37 * An extra flag to give if only the extension should be added as 38 * translation. This is obviously only of importance on Unix and other 39 * operating systems where the translation also may prefix the name with 40 * something, like 'lib', and ignored everywhere else. This flag is also 41 * ignored if DSO_FLAG_NO_NAME_TRANSLATION is used at the same time. 42 */ 43 # define DSO_FLAG_NAME_TRANSLATION_EXT_ONLY 0x02 44 45 /* 46 * Don't unload the DSO when we call DSO_free() 47 */ 48 # define DSO_FLAG_NO_UNLOAD_ON_FREE 0x04 49 /* 50 * The following flag controls the translation of symbol names to upper case. 51 * This is currently only being implemented for OpenVMS. 52 */ 53 # define DSO_FLAG_UPCASE_SYMBOL 0x10 54 55 /* 56 * This flag loads the library with public symbols. Meaning: The exported 57 * symbols of this library are public to all libraries loaded after this 58 * library. At the moment only implemented in unix. 59 */ 60 # define DSO_FLAG_GLOBAL_SYMBOLS 0x20 61 62 typedef void (*DSO_FUNC_TYPE) (void); 63 64 typedef struct dso_st DSO; 65 typedef struct dso_meth_st DSO_METHOD; 66 67 /* 68 * The function prototype used for method functions (or caller-provided 69 * callbacks) that transform filenames. They are passed a DSO structure 70 * pointer (or NULL if they are to be used independently of a DSO object) and 71 * a filename to transform. They should either return NULL (if there is an 72 * error condition) or a newly allocated string containing the transformed 73 * form that the caller will need to free with OPENSSL_free() when done. 74 */ 75 typedef char *(*DSO_NAME_CONVERTER_FUNC)(DSO *, const char *); 76 /* 77 * The function prototype used for method functions (or caller-provided 78 * callbacks) that merge two file specifications. They are passed a DSO 79 * structure pointer (or NULL if they are to be used independently of a DSO 80 * object) and two file specifications to merge. They should either return 81 * NULL (if there is an error condition) or a newly allocated string 82 * containing the result of merging that the caller will need to free with 83 * OPENSSL_free() when done. Here, merging means that bits and pieces are 84 * taken from each of the file specifications and added together in whatever 85 * fashion that is sensible for the DSO method in question. The only rule 86 * that really applies is that if the two specification contain pieces of the 87 * same type, the copy from the first string takes priority. One could see 88 * it as the first specification is the one given by the user and the second 89 * being a bunch of defaults to add on if they're missing in the first. 90 */ 91 typedef char *(*DSO_MERGER_FUNC)(DSO *, const char *, const char *); 92 93 DSO *DSO_new(void); 94 int DSO_free(DSO *dso); 95 int DSO_flags(DSO *dso); 96 int DSO_up_ref(DSO *dso); 97 long DSO_ctrl(DSO *dso, int cmd, long larg, void *parg); 98 99 /* 100 * These functions can be used to get/set the platform-independent filename 101 * used for a DSO. NB: set will fail if the DSO is already loaded. 102 */ 103 const char *DSO_get_filename(DSO *dso); 104 int DSO_set_filename(DSO *dso, const char *filename); 105 /* 106 * This function will invoke the DSO's name_converter callback to translate a 107 * filename, or if the callback isn't set it will instead use the DSO_METHOD's 108 * converter. If "filename" is NULL, the "filename" in the DSO itself will be 109 * used. If the DSO_FLAG_NO_NAME_TRANSLATION flag is set, then the filename is 110 * simply duplicated. NB: This function is usually called from within a 111 * DSO_METHOD during the processing of a DSO_load() call, and is exposed so 112 * that caller-created DSO_METHODs can do the same thing. A non-NULL return 113 * value will need to be OPENSSL_free()'d. 114 */ 115 char *DSO_convert_filename(DSO *dso, const char *filename); 116 /* 117 * This function will invoke the DSO's merger callback to merge two file 118 * specifications, or if the callback isn't set it will instead use the 119 * DSO_METHOD's merger. A non-NULL return value will need to be 120 * OPENSSL_free()'d. 121 */ 122 char *DSO_merge(DSO *dso, const char *filespec1, const char *filespec2); 123 124 /* 125 * The all-singing all-dancing load function, you normally pass NULL for the 126 * first and third parameters. Use DSO_up_ref and DSO_free for subsequent 127 * reference count handling. Any flags passed in will be set in the 128 * constructed DSO after its init() function but before the load operation. 129 * If 'dso' is non-NULL, 'flags' is ignored. 130 */ 131 DSO *DSO_load(DSO *dso, const char *filename, DSO_METHOD *meth, int flags); 132 133 /* This function binds to a function inside a shared library. */ 134 DSO_FUNC_TYPE DSO_bind_func(DSO *dso, const char *symname); 135 136 /* 137 * This method is the default, but will beg, borrow, or steal whatever method 138 * should be the default on any particular platform (including 139 * DSO_METH_null() if necessary). 140 */ 141 DSO_METHOD *DSO_METHOD_openssl(void); 142 143 /* 144 * This function writes null-terminated pathname of DSO module containing 145 * 'addr' into 'sz' large caller-provided 'path' and returns the number of 146 * characters [including trailing zero] written to it. If 'sz' is 0 or 147 * negative, 'path' is ignored and required amount of characters [including 148 * trailing zero] to accommodate pathname is returned. If 'addr' is NULL, then 149 * pathname of cryptolib itself is returned. Negative or zero return value 150 * denotes error. 151 */ 152 int DSO_pathbyaddr(void *addr, char *path, int sz); 153 154 /* 155 * Like DSO_pathbyaddr() but instead returns a handle to the DSO for the symbol 156 * or NULL on error. 157 */ 158 DSO *DSO_dsobyaddr(void *addr, int flags); 159 160 /* 161 * This function should be used with caution! It looks up symbols in *all* 162 * loaded modules and if module gets unloaded by somebody else attempt to 163 * dereference the pointer is doomed to have fatal consequences. Primary 164 * usage for this function is to probe *core* system functionality, e.g. 165 * check if getnameinfo(3) is available at run-time without bothering about 166 * OS-specific details such as libc.so.versioning or where does it actually 167 * reside: in libc itself or libsocket. 168 */ 169 void *DSO_global_lookup(const char *name); 170 171 /* BEGIN ERROR CODES */ 172 /* 173 * The following lines are auto generated by the script mkerr.pl. Any changes 174 * made after this point may be overwritten when the script is next run. 175 */ 176 177 int ERR_load_DSO_strings(void); 178 179 /* Error codes for the DSO functions. */ 180 181 /* Function codes. */ 182 # define DSO_F_DLFCN_BIND_FUNC 100 183 # define DSO_F_DLFCN_LOAD 102 184 # define DSO_F_DLFCN_MERGER 130 185 # define DSO_F_DLFCN_NAME_CONVERTER 123 186 # define DSO_F_DLFCN_UNLOAD 103 187 # define DSO_F_DL_BIND_FUNC 104 188 # define DSO_F_DL_LOAD 106 189 # define DSO_F_DL_MERGER 131 190 # define DSO_F_DL_NAME_CONVERTER 124 191 # define DSO_F_DL_UNLOAD 107 192 # define DSO_F_DSO_BIND_FUNC 108 193 # define DSO_F_DSO_CONVERT_FILENAME 126 194 # define DSO_F_DSO_CTRL 110 195 # define DSO_F_DSO_FREE 111 196 # define DSO_F_DSO_GET_FILENAME 127 197 # define DSO_F_DSO_GLOBAL_LOOKUP 139 198 # define DSO_F_DSO_LOAD 112 199 # define DSO_F_DSO_MERGE 132 200 # define DSO_F_DSO_NEW_METHOD 113 201 # define DSO_F_DSO_PATHBYADDR 105 202 # define DSO_F_DSO_SET_FILENAME 129 203 # define DSO_F_DSO_UP_REF 114 204 # define DSO_F_VMS_BIND_SYM 115 205 # define DSO_F_VMS_LOAD 116 206 # define DSO_F_VMS_MERGER 133 207 # define DSO_F_VMS_UNLOAD 117 208 # define DSO_F_WIN32_BIND_FUNC 101 209 # define DSO_F_WIN32_GLOBALLOOKUP 142 210 # define DSO_F_WIN32_JOINER 135 211 # define DSO_F_WIN32_LOAD 120 212 # define DSO_F_WIN32_MERGER 134 213 # define DSO_F_WIN32_NAME_CONVERTER 125 214 # define DSO_F_WIN32_PATHBYADDR 109 215 # define DSO_F_WIN32_SPLITTER 136 216 # define DSO_F_WIN32_UNLOAD 121 217 218 /* Reason codes. */ 219 # define DSO_R_CTRL_FAILED 100 220 # define DSO_R_DSO_ALREADY_LOADED 110 221 # define DSO_R_EMPTY_FILE_STRUCTURE 113 222 # define DSO_R_FAILURE 114 223 # define DSO_R_FILENAME_TOO_BIG 101 224 # define DSO_R_FINISH_FAILED 102 225 # define DSO_R_INCORRECT_FILE_SYNTAX 115 226 # define DSO_R_LOAD_FAILED 103 227 # define DSO_R_NAME_TRANSLATION_FAILED 109 228 # define DSO_R_NO_FILENAME 111 229 # define DSO_R_NULL_HANDLE 104 230 # define DSO_R_SET_FILENAME_FAILED 112 231 # define DSO_R_STACK_ERROR 105 232 # define DSO_R_SYM_FAILURE 106 233 # define DSO_R_UNLOAD_FAILED 107 234 # define DSO_R_UNSUPPORTED 108 235 236 # ifdef __cplusplus 237 } 238 # endif 239 #endif 240