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/* $OpenBSD: resolve.h,v 1.29 2003/09/04 19:33:48 drahn Exp $ */
/*
* Copyright (c) 1998 Per Fogelstrom, Opsycon AB
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#ifndef _RESOLVE_H_
#define _RESOLVE_H_
#include <link.h>
#include <dlfcn.h>
struct load_list {
struct load_list *next;
void *start;
size_t size;
int prot;
Elf_Addr moff;
long foff;
};
/*
* Structure describing a loaded object.
* The head of this struct must be compatible
* with struct link_map in sys/link.h
*/
typedef struct elf_object {
Elf_Addr load_addr; /* Real load address */
char *load_name; /* Pointer to object name */
Elf_Dyn *load_dyn; /* Pointer to object dynamic data */
struct elf_object *next;
struct elf_object *prev;
/* End struct link_map compatible */
Elf_Addr load_offs; /* Load offset from link address */
struct load_list *load_list;
u_int32_t load_size;
Elf_Addr got_addr;
Elf_Addr got_start;
size_t got_size;
Elf_Addr plt_start;
size_t plt_size;
union {
u_long info[DT_NUM + DT_PROCNUM];
struct {
Elf_Addr null; /* Not used */
Elf_Addr needed; /* Not used */
Elf_Addr pltrelsz;
Elf_Addr *pltgot;
Elf_Addr *hash;
const char *strtab;
const Elf_Sym *symtab;
Elf_RelA *rela;
Elf_Addr relasz;
Elf_Addr relaent;
Elf_Addr strsz;
Elf_Addr syment;
void (*init)(void);
void (*fini)(void);
const char *soname;
const char *rpath;
Elf_Addr symbolic;
Elf_Rel *rel;
Elf_Addr relsz;
Elf_Addr relent;
Elf_Addr pltrel;
Elf_Addr debug;
Elf_Addr textrel;
Elf_Addr jmprel;
Elf_Addr bind_now;
} u;
} Dyn;
#define dyn Dyn.u
struct elf_object *dep_next; /* Shadow objects for resolve search */
int status;
#define STAT_RELOC_DONE 1
#define STAT_GOT_DONE 2
#define STAT_INIT_DONE 4
Elf_Phdr *phdrp;
int phdrc;
int refcount;
int obj_type;
#define OBJTYPE_LDR 1
#define OBJTYPE_EXE 2
#define OBJTYPE_LIB 3
#define OBJTYPE_DLO 4
int obj_flags;
Elf_Word *buckets;
u_int32_t nbuckets;
Elf_Word *chains;
u_int32_t nchains;
Elf_Dyn *dynamic;
struct dep_node *first_child;
struct dep_node *last_child;
} elf_object_t;
struct dep_node {
struct dep_node *next_sibling;
elf_object_t *data;
};
extern void _dl_rt_resolve(void);
void _dl_add_object(elf_object_t *object);
extern elf_object_t *_dl_finalize_object(const char *objname, Elf_Dyn *dynp,
const u_long *, const int objtype, const long laddr, const long loff);
extern void _dl_remove_object(elf_object_t *object);
extern elf_object_t *_dl_lookup_object(const char *objname);
extern elf_object_t *_dl_load_shlib(const char *, elf_object_t *, int, int);
extern void _dl_unload_shlib(elf_object_t *object);
extern int _dl_md_reloc(elf_object_t *object, int rel, int relsz);
extern void _dl_md_reloc_got(elf_object_t *object, int lazy);
Elf_Addr _dl_find_symbol(const char *name, elf_object_t *startlook,
const Elf_Sym **ref, int flags, int sym_size, elf_object_t *object);
Elf_Addr _dl_find_symbol_bysym(elf_object_t *req_obj, unsigned int symidx,
elf_object_t *startlook, const Elf_Sym **ref, int flags, int req_size);
/*
* defines for _dl_find_symbol() flag field, three bits of meaning
* myself - clear: search all objects, set: search only this object
* warnnotfound - clear: no warning, set: warn if not found
* inplt - clear: possible plt ref set: real matching function.
*
* inplt - due to how ELF handles function addresses in shared libraries
* &func may actually refer to the plt entry in the main program
* rather than the actual function address in the .so file.
* This rather bizarre behavior is documented in the SVR4 ABI.
* when getting the function address to relocate a PLT entry
* the 'real' function address is necessary, not the possible PLT address.
*/
/* myself */
#define SYM_SEARCH_ALL 0
#define SYM_SEARCH_SELF 1
/* warnnotfound */
#define SYM_NOWARNNOTFOUND 0
#define SYM_WARNNOTFOUND 2
/* inplt */
#define SYM_NOTPLT 0
#define SYM_PLT 4
void _dl_rtld(elf_object_t *object);
void _dl_call_init(elf_object_t *object);
void _dl_link_sub(elf_object_t *dep, elf_object_t *p);
void _dl_run_dtors(elf_object_t *object);
Elf_Addr _dl_bind(elf_object_t *object, int index);
int _dl_match_file(struct sod *sodp, char *name, int namelen);
char *_dl_find_shlib(struct sod *sodp, const char *searchpath, int nohints);
void _dl_load_list_free(struct load_list *load_list);
extern elf_object_t *_dl_objects;
extern elf_object_t *_dl_last_object;
extern const char *_dl_progname;
extern struct r_debug *_dl_debug_map;
extern int _dl_pagesz;
extern int _dl_errno;
extern char *_dl_libpath;
extern char *_dl_preload;
extern char *_dl_bindnow;
extern char *_dl_traceld;
extern char *_dl_debug;
#define DL_DEB(P) do { if (_dl_debug) _dl_printf P ; } while (0)
#define DL_NOT_FOUND 1
#define DL_CANT_OPEN 2
#define DL_NOT_ELF 3
#define DL_CANT_OPEN_REF 4
#define DL_CANT_MMAP 5
#define DL_NO_SYMBOL 6
#define DL_INVALID_HANDLE 7
#define DL_INVALID_CTL 8
#define ELF_ROUND(x,malign) (((x) + (malign)-1) & ~((malign)-1))
#define ELF_TRUNC(x,malign) ((x) & ~((malign)-1))
/* symbol lookup cache */
typedef struct sym_cache {
const Elf_Sym *sym;
Elf_Addr offset;
int flags;
} sym_cache;
extern sym_cache *_dl_symcache;
#endif /* _RESOLVE_H_ */
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