1 2 /*--------------------------------------------------------------------*/ 3 /*--- Function replacement and wrapping. pub_core_redir.h ---*/ 4 /*--------------------------------------------------------------------*/ 5 6 /* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2000-2017 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 #ifndef __PUB_CORE_REDIR_H 32 #define __PUB_CORE_REDIR_H 33 34 //-------------------------------------------------------------------- 35 // PURPOSE: This module deals with: 36 // 37 // - code replacement: intercepting calls to client functions, and 38 // pointing them to a different piece of code. 39 // 40 // - loading notification: telling the core where certain client-space 41 // functions are when they get loaded. 42 // 43 // - function wrapping: add calls to code before and after client 44 // functions execute, for inspection and/or modification. 45 // 46 // - checking of --require-text-symbol= specifications: when a new 47 // object is loaded, its symbol table is examined, and if a symbol 48 // (as required by the specifications) is not found then the run 49 // is aborted. See comment by VG_(clo_n_req_tsyms) in 50 // pub_core_options.h for background. This doesn't have anything 51 // to do with function intercepting or wrapping, but it does have 52 // to do with examining all symbols at object load time, so this 53 // module seems like a logical place to put it. 54 // 55 //-------------------------------------------------------------------- 56 57 #include "pub_tool_redir.h" 58 #include "pub_core_basics.h" // Addr 59 #include "pub_core_debuginfo.h" // DebugInfo 60 61 //-------------------------------------------------------------------- 62 // Notifications - by which we are told of state changes 63 //-------------------------------------------------------------------- 64 65 /* Notify the module of a new DebugInfo (called from m_debuginfo). */ 66 extern void VG_(redir_notify_new_DebugInfo)( const DebugInfo* ); 67 68 /* Notify the module of the disappearance of a DebugInfo (also called 69 from m_debuginfo). */ 70 extern void VG_(redir_notify_delete_DebugInfo)( const DebugInfo* ); 71 72 /* Initialise the module, and load initial "hardwired" redirects. */ 73 extern void VG_(redir_initialise)( void ); 74 75 /* Notify the module of a new target for an indirect function. */ 76 extern void VG_(redir_add_ifunc_target)( Addr old_from, Addr new_from ); 77 78 //-------------------------------------------------------------------- 79 // Queries 80 //-------------------------------------------------------------------- 81 82 /* This is the crucial redirection function. It answers the question: 83 should this code address be redirected somewhere else? It's used 84 just before translating a basic block. If a redir is found, 85 *isWrap allows to distinguish wrap- from replace- style 86 redirections. */ 87 extern Addr VG_(redir_do_lookup) ( Addr orig, Bool* isWrap ); 88 89 90 //-------------------------------------------------------------------- 91 // Loading notification 92 //-------------------------------------------------------------------- 93 94 /* Functions named with this macro have the property that the core will 95 be told what their address is when they are loaded. This can be useful 96 if the core wants to call them at some point, and so needs to know their 97 address. This is a weaker but more general mechanism than code 98 replacement. 99 100 Functions named with this macro should be in client space, ie. in 101 vgpreload_<tool>.h or vgpreload_core.h. */ 102 103 #define VG_NOTIFY_ON_LOAD(name) _vgnU_##name 104 #define VG_NOTIFY_ON_LOAD_PREFIX "_vgnU_" 105 #define VG_NOTIFY_ON_LOAD_PREFIX_LEN 6 106 107 108 //-------------------------------------------------------------------- 109 // Function wrapping 110 //-------------------------------------------------------------------- 111 112 // This is currently not working(?) --njn 113 114 /* Wrapping machinery */ 115 //enum return_type { 116 // RT_RETURN, 117 // RT_LONGJMP, 118 // RT_EXIT, 119 //}; 120 // 121 //typedef struct _FuncWrapper FuncWrapper; 122 //struct _FuncWrapper { 123 // void *(*before)(va_list args); 124 // void (*after) (void *nonce, enum return_type, Word retval); 125 //}; 126 // 127 //extern void VG_(wrap_function)(Addr eip, const FuncWrapper *wrapper); 128 //extern const FuncWrapper *VG_(is_wrapped)(Addr eip); 129 //extern Bool VG_(is_wrapper_return)(Addr eip); 130 131 /* Primary interface for adding wrappers for client-side functions. */ 132 //extern CodeRedirect *VG_(add_wrapper)(const HChar *from_lib, const HChar *from_sym, 133 // const FuncWrapper *wrapper); 134 // 135 //extern Bool VG_(is_resolved)(const CodeRedirect *redir); 136 137 #endif // __PUB_CORE_REDIR_H 138 139 /*--------------------------------------------------------------------*/ 140 /*--- end ---*/ 141 /*--------------------------------------------------------------------*/ 142