1 /* Copyright © 2013, Intel Corporation 2 * 3 * Permission is hereby granted, free of charge, to any person obtaining a copy 4 * of this software and associated documentation files (the "Software"), to deal 5 * in the Software without restriction, including without limitation the rights 6 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 7 * copies of the Software, and to permit persons to whom the Software is 8 * furnished to do so, subject to the following conditions: 9 * 10 * The above copyright notice and this permission notice shall be included in 11 * all copies or substantial portions of the Software. 12 * 13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 16 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 17 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 18 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 19 * THE SOFTWARE. 20 */ 21 22 #ifndef DLWRAP_H 23 #define DLWRAP_H 24 25 #define _GNU_SOURCE 26 #include <dlfcn.h> 27 28 /* Call the *real* dlopen. We have our own wrapper for dlopen that, of 29 * necessity must use claim the symbol 'dlopen'. So whenever anything 30 * internal needs to call the real, underlying dlopen function, the 31 * thing to call is dlwrap_real_dlopen. 32 */ 33 void * 34 dlwrap_real_dlopen(const char *filename, int flag); 35 36 /* Perform a dlopen on the libfips library itself. 37 * 38 * Many places in fips need to lookup symbols within the libfips 39 * library itself, (and not in any other library). This function 40 * provides a reliable way to get a handle for performing such 41 * lookups. 42 * 43 * The returned handle can be passed to dlwrap_real_dlsym for the 44 * lookups. */ 45 void * 46 dlwrap_dlopen_libfips(void); 47 48 /* Call the *real* dlsym. We have our own wrapper for dlsym that, of 49 * necessity must use claim the symbol 'dlsym'. So whenever anything 50 * internal needs to call the real, underlying dlysm function, the 51 * thing to call is dlwrap_real_dlsym. 52 */ 53 void * 54 dlwrap_real_dlsym(void *handle, const char *symbol); 55 56 #define DEFER_TO_GL(library, func, name, args) \ 57 ({ \ 58 void *lib = dlwrap_real_dlopen(library, RTLD_LAZY | RTLD_LOCAL); \ 59 typeof(&func) real_func = dlwrap_real_dlsym(lib, name); \ 60 /* gcc extension -- func's return value is the return value of \ 61 * the statement. \ 62 */ \ 63 real_func args; \ 64 }) 65 66 #endif 67 68