1 /* $NetBSD: hijackdlsym.c,v 1.5 2013/09/10 16:53:06 pooka Exp $ */ 2 3 /*- 4 * Copyright (c) 2011 Antti Kantee. All Rights Reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <rump/rumpuser_port.h> 29 30 #if !defined(lint) 31 __RCSID("$NetBSD: hijackdlsym.c,v 1.5 2013/09/10 16:53:06 pooka Exp $"); 32 #endif 33 34 #include <dlfcn.h> 35 36 #include "hijack.h" 37 38 /* 39 * This is called from librumpclient in case of LD_PRELOAD. 40 * It ensures correct RTLD_NEXT. 41 * 42 * (note, this module is compiled with -O0 to make sure this 43 * function is not treated as a tailcall or other optimizations 44 * applied) 45 */ 46 47 /* why is this indirection required for powerpc ???? */ 48 static void * __noinline 49 bouncer(void *handle, const char *symbol) 50 { 51 52 return dlsym(handle, symbol); 53 } 54 55 void * 56 rumphijack_dlsym(void *handle, const char *symbol) 57 { 58 59 return bouncer(handle, symbol); 60 } 61