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 (at) 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 56 void VG_NOTIFY_ON_LOAD(freeres)( void ); 57 void VG_NOTIFY_ON_LOAD(freeres)( void ) 58 { 59 # if !defined(__UCLIBC__) \ 60 && !defined(__ANDROID__) 61 extern void __libc_freeres(void); 62 __libc_freeres(); 63 # endif 64 VALGRIND_DO_CLIENT_REQUEST_STMT(VG_USERREQ__LIBC_FREERES_DONE, 65 0, 0, 0, 0, 0); 66 /*NOTREACHED*/ 67 *(volatile int *)0 = 'x'; 68 } 69 70 /* --------------------------------------------------------------------- 71 Wrapper for indirect functions which need to be redirected. 72 ------------------------------------------------------------------ */ 73 74 void * VG_NOTIFY_ON_LOAD(ifunc_wrapper) (void); 75 void * VG_NOTIFY_ON_LOAD(ifunc_wrapper) (void) 76 { 77 OrigFn fn; 78 Addr result = 0; 79 Addr fnentry; 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 #if defined(VGP_ppc64be_linux) 86 /* ppc64be uses function descriptors, so get the actual function entry 87 address for the client request, but return the function descriptor 88 from this function. 89 result points to the function descriptor, which starts with the 90 function entry. */ 91 fnentry = *(Addr*)result; 92 #else 93 fnentry = result; 94 #endif 95 96 /* Ask the valgrind core running on the real CPU (as opposed to this 97 code which runs on the emulated CPU) to update the redirection that 98 led to this function. This client request eventually gives control to 99 the function VG_(redir_add_ifunc_target) in m_redir.c */ 100 VALGRIND_DO_CLIENT_REQUEST_STMT(VG_USERREQ__ADD_IFUNC_TARGET, 101 fn.nraddr, fnentry, 0, 0, 0); 102 return (void*)result; 103 } 104 105 #elif defined(VGO_darwin) 106 107 #include "config.h" /* VERSION */ 108 109 /* --------------------------------------------------------------------- 110 Darwin crash log hints 111 ------------------------------------------------------------------ */ 112 113 /* This string will be inserted into crash logs, so crashes while 114 running under Valgrind can be distinguished from other crashes. */ 115 __private_extern__ const char *__crashreporter_info__ = "Instrumented by Valgrind " VERSION; 116 117 /* --------------------------------------------------------------------- 118 Darwin environment cleanup 119 ------------------------------------------------------------------ */ 120 121 /* Scrubbing DYLD_INSERT_LIBRARIES from envp during exec is insufficient, 122 as there are other ways to launch a process with environment that 123 valgrind can't catch easily (i.e. launchd). 124 Instead, scrub DYLD_INSERT_LIBRARIES from the parent process once 125 dyld is done loading vg_preload.so. 126 */ 127 #include <string.h> 128 #include <crt_externs.h> 129 130 // GrP fixme copied from m_libcproc 131 static void env_unsetenv ( HChar **env, const HChar *varname ) 132 { 133 HChar **from; 134 HChar **to = NULL; 135 Int len = strlen(varname); 136 137 for (from = to = env; from && *from; from++) { 138 if (!(strncmp(varname, *from, len) == 0 && (*from)[len] == '=')) { 139 *to = *from; 140 to++; 141 } 142 } 143 *(to++) = *(from++); 144 /* fix the 4th "char* apple" pointer (aka. executable path pointer) */ 145 *(to++) = *(from++); 146 *to = NULL; 147 } 148 149 static void vg_cleanup_env(void) __attribute__((constructor)); 150 static void vg_cleanup_env(void) 151 { 152 HChar **envp = (HChar**)*_NSGetEnviron(); 153 env_unsetenv(envp, "VALGRIND_LAUNCHER"); 154 env_unsetenv(envp, "DYLD_SHARED_REGION"); 155 // GrP fixme should be more like mash_colon_env() 156 env_unsetenv(envp, "DYLD_INSERT_LIBRARIES"); 157 } 158 159 /* --------------------------------------------------------------------- 160 Darwin arc4random (rdar://6166275) 161 ------------------------------------------------------------------ */ 162 163 #include <fcntl.h> 164 #include <unistd.h> 165 166 int VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random)(void); 167 int VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random)(void) 168 { 169 static int rnd = -1; 170 int result; 171 172 if (rnd < 0) rnd = open("/dev/random", O_RDONLY); 173 174 read(rnd, &result, sizeof(result)); 175 return result; 176 } 177 178 void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_stir)(void); 179 void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_stir)(void) 180 { 181 // do nothing 182 } 183 184 void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_addrandom)(unsigned char *dat, int datlen); 185 void VG_REPLACE_FUNCTION_ZU(libSystemZdZaZddylib, arc4random_addrandom)(unsigned char *dat, int datlen) 186 { 187 // do nothing 188 // GrP fixme ought to check [dat..dat+datlen) is defined 189 // but don't care if it's initialized 190 } 191 192 #else 193 194 # error Unknown OS 195 #endif 196 197 /*--------------------------------------------------------------------*/ 198 /*--- end ---*/ 199 /*--------------------------------------------------------------------*/ 200
