resolve.h revision 1.22
1/* $OpenBSD: resolve.h,v 1.22 2003/02/15 22:39:13 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 Elf_Addr got_start; 66 size_t got_size; 67 Elf_Addr plt_start; 68 size_t plt_size; 69 70 union { 71 u_long info[DT_NUM + DT_PROCNUM]; 72 struct { 73 Elf_Addr null; /* Not used */ 74 Elf_Addr needed; /* Not used */ 75 Elf_Addr pltrelsz; 76 Elf_Addr *pltgot; 77 Elf_Addr *hash; 78 const char *strtab; 79 const Elf_Sym *symtab; 80 Elf_RelA *rela; 81 Elf_Addr relasz; 82 Elf_Addr relaent; 83 Elf_Addr strsz; 84 Elf_Addr syment; 85 void (*init)(void); 86 void (*fini)(void); 87 const char *soname; 88 const char *rpath; 89 Elf_Addr symbolic; 90 Elf_Rel *rel; 91 Elf_Addr relsz; 92 Elf_Addr relent; 93 Elf_Addr pltrel; 94 Elf_Addr debug; 95 Elf_Addr textrel; 96 Elf_Addr jmprel; 97 Elf_Addr bind_now; 98 } u; 99 } Dyn; 100#define dyn Dyn.u 101 102 struct elf_object *dep_next; /* Shadow objects for resolve search */ 103 104 int status; 105#define STAT_RELOC_DONE 1 106#define STAT_GOT_DONE 2 107#define STAT_INIT_DONE 4 108 109 Elf_Phdr *phdrp; 110 int phdrc; 111 112 int refcount; 113 int obj_type; 114#define OBJTYPE_LDR 1 115#define OBJTYPE_EXE 2 116#define OBJTYPE_LIB 3 117#define OBJTYPE_DLO 4 118 119 Elf_Word *buckets; 120 u_int32_t nbuckets; 121 Elf_Word *chains; 122 u_int32_t nchains; 123 Elf_Dyn *dynamic; 124 125 struct dep_node *first_child; 126 struct dep_node *last_child; 127} elf_object_t; 128 129struct dep_node { 130 struct dep_node *next_sibling; 131 elf_object_t *data; 132}; 133 134extern void _dl_rt_resolve(void); 135 136extern elf_object_t *_dl_add_object(const char *objname, Elf_Dyn *dynp, 137 const u_long *, const int objtype, 138 const long laddr, const long loff); 139extern void _dl_remove_object(elf_object_t *object); 140 141extern elf_object_t *_dl_lookup_object(const char *objname); 142extern elf_object_t *_dl_load_shlib(const char *, elf_object_t *, int); 143extern void _dl_unload_shlib(elf_object_t *object); 144 145extern int _dl_md_reloc(elf_object_t *object, int rel, int relsz); 146extern void _dl_md_reloc_got(elf_object_t *object, int lazy); 147 148Elf_Addr _dl_find_symbol(const char *name, elf_object_t *startlook, 149 const Elf_Sym **ref, int flags, int sym_size, const char *module_name); 150/* 151 * defines for _dl_find_symbol() flag field, three bits of meaning 152 * myself - clear: search all objects, set: search only this object 153 * warnnotfound - clear: no warning, set: warn if not found 154 * inplt - clear: possible plt ref set: real matching function. 155 * 156 * inplt - due to how ELF handles function addresses in shared libraries 157 * &func may actually refer to the plt entry in the main program 158 * rather than the actual function address in the .so file. 159 * This rather bizarre behavior is documented in the SVR4 ABI. 160 * when getting the function address to relocate a PLT entry 161 * the 'real' function address is necessary, not the possible PLT address. 162 */ 163/* myself */ 164#define SYM_SEARCH_ALL 0 165#define SYM_SEARCH_SELF 1 166/* warnnotfound */ 167#define SYM_NOWARNNOTFOUND 0 168#define SYM_WARNNOTFOUND 2 169/* inplt */ 170#define SYM_NOTPLT 0 171#define SYM_PLT 4 172 173void _dl_rtld(elf_object_t *object); 174void _dl_call_init(elf_object_t *object); 175 176extern elf_object_t *_dl_objects; 177extern elf_object_t *_dl_last_object; 178 179extern const char *_dl_progname; 180extern struct r_debug *_dl_debug_map; 181 182extern int _dl_pagesz; 183extern int _dl_errno; 184 185extern char *_dl_libpath; 186extern char *_dl_preload; 187extern char *_dl_bindnow; 188extern char *_dl_traceld; 189extern char *_dl_debug; 190 191#define DL_DEB(P) do { if (_dl_debug) _dl_printf P ; } while (0) 192 193#define DL_NOT_FOUND 1 194#define DL_CANT_OPEN 2 195#define DL_NOT_ELF 3 196#define DL_CANT_OPEN_REF 4 197#define DL_CANT_MMAP 5 198#define DL_NO_SYMBOL 6 199#define DL_INVALID_HANDLE 7 200#define DL_INVALID_CTL 8 201 202#define ELF_ROUND(x,malign) (((x) + (malign)-1) & ~((malign)-1)) 203#define ELF_TRUNC(x,malign) ((x) & ~((malign)-1)) 204 205#endif /* _RESOLVE_H_ */ 206