1 2/*--------------------------------------------------------------------*/ 3/*--- Client-space code for the core. vg_preloaded.c ---*/ 4/*--------------------------------------------------------------------*/ 5 6/* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2000-2013 Julian Seward 11 jseward@acm.org 12 13 This program is free software; you can redistribute it and/or 14 modify it under the terms of the GNU General Public License as 15 published by the Free Software Foundation; either version 2 of the 16 License, or (at your option) any later version. 17 18 This program is distributed in the hope that it will be useful, but 19 WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with this program; if not, write to the Free Software 25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 26 02111-1307, USA. 27 28 The GNU General Public License is contained in the file COPYING. 29*/ 30 31 32/* --------------------------------------------------------------------- 33 ALL THE CODE IN THIS FILE RUNS ON THE SIMULATED CPU. 34 35 These functions are not called directly - they're the targets of code 36 redirection or load notifications (see pub_core_redir.h for info). 37 They're named weirdly so that the intercept code can find them when the 38 shared object is initially loaded. 39 40 Note that this filename has the "vg_" prefix because it can appear 41 in stack traces, and the "vg_" makes it a little clearer that it 42 originates from Valgrind. 43 ------------------------------------------------------------------ */ 44 45#include "pub_core_basics.h" 46#include "pub_core_clreq.h" 47#include "pub_core_debuginfo.h" // Needed for pub_core_redir.h 48#include "pub_core_redir.h" // For VG_NOTIFY_ON_LOAD 49 50#if defined(VGO_linux) 51 52/* --------------------------------------------------------------------- 53 Hook for running __libc_freeres once the program exits. 54 ------------------------------------------------------------------ */ 55 56void VG_NOTIFY_ON_LOAD(freeres)( void ); 57void VG_NOTIFY_ON_LOAD(freeres)( void ) 58{ 59# if !defined(__UCLIBC__) \ 60 && !defined(VGPV_arm_linux_android) && !defined(VGPV_x86_linux_android) \ 61 && !defined(VGPV_mips32_linux_android) && !defined(VGPV_arm64_linux_android) 62 extern void __libc_freeres(void); 63 __libc_freeres(); 64# endif 65 VALGRIND_DO_CLIENT_REQUEST_STMT(VG_USERREQ__LIBC_FREERES_DONE, 66 0, 0, 0, 0, 0); 67 /*NOTREACHED*/ 68 *(volatile int *)0 = 'x'; 69} 70 71/* --------------------------------------------------------------------- 72 Wrapper for indirect functions which need to be redirected. 73 ------------------------------------------------------------------ */ 74 75void * VG_NOTIFY_ON_LOAD(ifunc_wrapper) (void); 76void * VG_NOTIFY_ON_LOAD(ifunc_wrapper) (void) 77{ 78 OrigFn fn; 79 Addr result = 0; 80 81 /* Call the original indirect function and get it's result */ 82 VALGRIND_GET_ORIG_FN(fn); 83 CALL_FN_W_v(result, fn); 84 85 /* Ask the valgrind core running on the real CPU (as opposed to this 86 code which runs on the emulated CPU) to update the redirection that 87 led to this function. This client request eventually gives control to 88 the function VG_(redir_add_ifunc_target) in m_redir.c */ 89 VALGRIND_DO_CLIENT_REQUEST_STMT(VG_USERREQ__ADD_IFUNC_TARGET, 90 fn.nraddr, result, 0, 0, 0); 91 return (void*)result; 92} 93 94#elif defined(VGO_darwin) 95 96#include "config.h" /* VERSION */ 97 98/* --------------------------------------------------------------------- 99 Darwin crash log hints 100 ------------------------------------------------------------------ */ 101 102/* This string will be inserted into crash logs, so crashes while 103 running under Valgrind can be distinguished from other crashes. */ 104__private_extern__ const char *__crashreporter_info__ = "Instrumented by Valgrind " VERSION; 105 106/* --------------------------------------------------------------------- 107 Darwin environment cleanup 108 ------------------------------------------------------------------ */ 109 110/* Scrubbing DYLD_INSERT_LIBRARIES from envp during exec is insufficient, 111 as there are other ways to launch a process with environment that 112 valgrind can't catch easily (i.e. launchd). 113 Instead, scrub DYLD_INSERT_LIBRARIES from the parent process once 114 dyld is done loading vg_preload.so. 115*/ 116#include <string.h> 117#include <crt_externs.h> 118 119// GrP fixme copied from m_libcproc 120static void env_unsetenv ( HChar **env, const HChar *varname ) 121{ 122 HChar **from; 123 HChar **to = NULL; 124 Int len = strlen(varname); 125 126 for (from = to = env; from && *from; from++) { 127 if (!(strncmp(varname, *from, len) == 0 && (*from)[len] == '=')) { 128 *to = *from; 129 to++; 130 } 131 } 132 *(to++) = *(from++); 133 /* fix the 4th "char* apple" pointer (aka. executable path pointer) */ 134 *(to++) = *(from++); 135 *to = NULL; 136} 137 138static void vg_cleanup_env(void) __attribute__((constructor)); 139static void vg_cleanup_env(void) 140{ 141 HChar **envp = (HChar**)*_NSGetEnviron(); 142 env_unsetenv(envp, "VALGRIND_LAUNCHER"); 143 env_unsetenv(envp, "DYLD_SHARED_REGION"); 144 // GrP fixme should be more like mash_colon_env() 145 env_unsetenv(envp, "DYLD_INSERT_LIBRARIES"); 146} 147 148/* --------------------------------------------------------------------- 149 Darwin arc4random (rdar://6166275) 150 ------------------------------------------------------------------ */ 151 152#include <fcntl.h> 153#include <unistd.h> 154 155int VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random)(void); 156int VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random)(void) 157{ 158 static int rnd = -1; 159 int result; 160 161 if (rnd < 0) rnd = open("/dev/random", O_RDONLY); 162 163 read(rnd, &result, sizeof(result)); 164 return result; 165} 166 167void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_stir)(void); 168void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_stir)(void) 169{ 170 // do nothing 171} 172 173void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_addrandom)(unsigned char *dat, int datlen); 174void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_addrandom)(unsigned char *dat, int datlen) 175{ 176 // do nothing 177 // GrP fixme ought to check [dat..dat+datlen) is defined 178 // but don't care if it's initialized 179} 180 181#else 182 183# error Unknown OS 184#endif 185 186/*--------------------------------------------------------------------*/ 187/*--- end ---*/ 188/*--------------------------------------------------------------------*/ 189