resolve.h revision 1.19
1/* $OpenBSD: resolve.h,v 1.19 2002/12/18 19:20:01 drahn Exp $ */ 2 3/* 4 * Copyright (c) 1998 Per Fogelstrom, Opsycon AB 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 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed under OpenBSD by 17 * Per Fogelstrom, Opsycon AB, Sweden. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 22 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 25 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 */ 34 35#ifndef _RESOLVE_H_ 36#define _RESOLVE_H_ 37 38#include <link.h> 39 40struct load_list { 41 struct load_list *next; 42 char *start; 43 size_t size; 44 int prot; 45}; 46 47/* 48 * Structure describing a loaded object. 49 * The head of this struct must be compatible 50 * with struct link_map in sys/link.h 51 */ 52typedef struct elf_object { 53 Elf_Addr load_addr; /* Real load address */ 54 char *load_name; /* Pointer to object name */ 55 Elf_Dyn *load_dyn; /* Pointer to object dynamic data */ 56 struct elf_object *next; 57 struct elf_object *prev; 58/* End struct link_map compatible */ 59 Elf_Addr load_offs; /* Load offset from link address */ 60 61 struct load_list *load_list; 62 63 u_int32_t load_size; 64 Elf_Addr got_addr; 65 size_t got_size; 66 Elf_Addr plt_addr; 67 size_t plt_size; 68 69 union { 70 u_long info[DT_NUM + DT_PROCNUM]; 71 struct { 72 Elf_Addr null; /* Not used */ 73 Elf_Addr needed; /* Not used */ 74 Elf_Addr pltrelsz; 75 Elf_Addr *pltgot; 76 Elf_Addr *hash; 77 const char *strtab; 78 const Elf_Sym *symtab; 79 Elf_RelA *rela; 80 Elf_Addr relasz; 81 Elf_Addr relaent; 82 Elf_Addr strsz; 83 Elf_Addr syment; 84 void (*init)(void); 85 void (*fini)(void); 86 const char *soname; 87 const char *rpath; 88 Elf_Addr symbolic; 89 Elf_Rel *rel; 90 Elf_Addr relsz; 91 Elf_Addr relent; 92 Elf_Addr pltrel; 93 Elf_Addr debug; 94 Elf_Addr textrel; 95 Elf_Addr jmprel; 96 Elf_Addr bind_now; 97 } u; 98 } Dyn; 99#define dyn Dyn.u 100 101 struct elf_object *dep_next; /* Shadow objects for resolve search */ 102 103 int status; 104#define STAT_RELOC_DONE 1 105#define STAT_GOT_DONE 2 106#define STAT_INIT_DONE 4 107 108 Elf_Phdr *phdrp; 109 int phdrc; 110 111 int refcount; 112 int obj_type; 113#define OBJTYPE_LDR 1 114#define OBJTYPE_EXE 2 115#define OBJTYPE_LIB 3 116#define OBJTYPE_DLO 4 117 118 Elf_Word *buckets; 119 u_int32_t nbuckets; 120 Elf_Word *chains; 121 u_int32_t nchains; 122 Elf_Dyn *dynamic; 123 124} elf_object_t; 125 126extern void _dl_rt_resolve(void); 127 128extern elf_object_t *_dl_add_object(const char *objname, Elf_Dyn *dynp, 129 const u_long *, const int objtype, 130 const long laddr, const long loff); 131extern void _dl_remove_object(elf_object_t *object); 132 133extern elf_object_t *_dl_lookup_object(const char *objname); 134extern elf_object_t *_dl_load_shlib(const char *, elf_object_t *, int); 135extern void _dl_unload_shlib(elf_object_t *object); 136 137extern int _dl_md_reloc(elf_object_t *object, int rel, int relsz); 138extern void _dl_md_reloc_got(elf_object_t *object, int lazy); 139 140Elf_Addr _dl_find_symbol(const char *name, elf_object_t *startlook, 141 const Elf_Sym **ref, int flags, int sym_size, const char *module_name); 142/* 143 * defines for _dl_find_symbol() flag field, three bits of meaning 144 * myself - clear: search all objects, set: search only this object 145 * warnnotfound - clear: no warning, set: warn if not found 146 * inplt - clear: possible plt ref set: real matching function. 147 * 148 * inplt - due to how ELF handles function addresses in shared libraries 149 * &func may actually refer to the plt entry in the main program 150 * rather than the actual function address in the .so file. 151 * This rather bizarre behavior is documented in the SVR4 ABI. 152 * when getting the function address to relocate a PLT entry 153 * the 'real' function address is necessary, not the possible PLT address. 154 */ 155/* myself */ 156#define SYM_SEARCH_ALL 0 157#define SYM_SEARCH_SELF 1 158/* warnnotfound */ 159#define SYM_NOWARNNOTFOUND 0 160#define SYM_WARNNOTFOUND 2 161/* inplt */ 162#define SYM_NOTPLT 0 163#define SYM_PLT 4 164 165void _dl_rtld(elf_object_t *object); 166void _dl_call_init(elf_object_t *object); 167 168extern elf_object_t *_dl_objects; 169extern elf_object_t *_dl_last_object; 170 171extern const char *_dl_progname; 172extern struct r_debug *_dl_debug_map; 173 174extern int _dl_pagesz; 175extern int _dl_errno; 176 177extern char *_dl_libpath; 178extern char *_dl_preload; 179extern char *_dl_bindnow; 180extern char *_dl_traceld; 181extern char *_dl_debug; 182 183#define DL_DEB(P) do { if (_dl_debug) _dl_printf P ; } while (0) 184 185#define DL_NOT_FOUND 1 186#define DL_CANT_OPEN 2 187#define DL_NOT_ELF 3 188#define DL_CANT_OPEN_REF 4 189#define DL_CANT_MMAP 5 190#define DL_NO_SYMBOL 6 191#define DL_INVALID_HANDLE 7 192#define DL_INVALID_CTL 8 193 194#endif /* _RESOLVE_H_ */ 195