/* $NetBSD: rtld.h,v 1.3 1997/02/14 22:30:25 cgd Exp $ */ /* * Copyright 1996 John D. Polstra. * Copyright 1996 Matt Thomas * All rights reserved. * * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by John Polstra. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * 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 RTLD_H /* { */ #define RTLD_H 1 #include #include #include #include #include "rtldenv.h" #include "link.h" #define RTLD_DEFAULT_LIBRARY_PATH "/usr/lib:/usr/local/lib" #if 0 #define SVR4_LIBDIR "/usr/lib" #endif #define LIBDIRLEN (sizeof LIBDIR - 1) #define SVR4_LIBDIRLEN (sizeof SVR4_LIBDIR - 1) #define PAGESIZE CLBYTES #define round_down(x) ((x) & ~(PAGESIZE-1)) #define round_up(x) round_down((x) + PAGESIZE - 1) #define NEW(type) ((type *) xmalloc(sizeof(type))) #define CNEW(type) ((type *) xcalloc(sizeof(type))) /* * C++ has mandated the use of the following keywords for its new boolean * type. We might as well follow their lead. */ typedef unsigned char bool; #define false 0 #define true 1 struct Struct_Obj_Entry; typedef struct Struct_Needed_Entry { struct Struct_Needed_Entry *next; struct Struct_Obj_Entry *obj; unsigned long name; /* Offset of name in string table */ } Needed_Entry; typedef struct _rtld_search_path_t { struct _rtld_search_path_t *sp_next; const char *sp_path; size_t sp_pathlen; } Search_Path; /* * Shared object descriptor. * * Items marked with "(%)" are dynamically allocated, and must be freed * when the structure is destroyed. */ #define RTLD_MAGIC 0xd550b87a #define RTLD_VERSION 1 typedef struct Struct_Obj_Entry { Elf32_Word magic; /* Magic number (sanity check) */ Elf32_Word version; /* Version number of struct format */ struct Struct_Obj_Entry *next; char *path; /* Pathname of underlying file (%) */ int refcount; int dl_refcount; /* Number of times loaded by dlopen */ /* These items are computed by map_object() or by digest_phdr(). */ caddr_t mapbase; /* Base address of mapped region */ size_t mapsize; /* Size of mapped region in bytes */ size_t textsize; /* Size of text segment in bytes */ Elf_Addr vaddrbase; /* Base address in shared object file */ caddr_t relocbase; /* Relocation constant = mapbase - vaddrbase */ Elf_Dyn *dynamic; /* Dynamic section */ caddr_t entry; /* Entry point */ const Elf_Phdr *phdr; /* Program header if it is mapped, else NULL */ size_t phsize; /* Size of program header in bytes */ /* Items from the dynamic section. */ Elf_Addr *pltgot; /* PLTGOT table */ const Elf_Rel *rel; /* Relocation entries */ const Elf_Rel *rellim; /* Limit of Relocation entries */ const Elf_RelA *rela; /* Relocation entries */ const Elf_RelA *relalim; /* Limit of Relocation entries */ const Elf_Rel *pltrel; /* PLT relocation entries */ const Elf_Rel *pltrellim; /* Limit of PLT relocation entries */ const Elf_RelA *pltrela; /* PLT relocation entries */ const Elf_RelA *pltrelalim; /* Limit of PLT relocation entries */ const Elf_Sym *symtab; /* Symbol table */ const char *strtab; /* String table */ unsigned long strsize; /* Size in bytes of string table */ const Elf_Word *buckets; /* Hash table buckets array */ unsigned long nbuckets; /* Number of buckets */ const Elf_Word *chains; /* Hash table chain array */ unsigned long nchains; /* Number of chains */ Search_Path *rpaths; /* Search path specified in object */ Needed_Entry *needed; /* Shared objects needed by this one (%) */ void (*init)(void); /* Initialization function to call */ void (*fini)(void); /* Termination function to call */ /* Entry points for dlopen() and friends. */ void *(*dlopen)(const char *, int); void *(*dlsym)(void *, const char *); char *(*dlerror)(void); int (*dlclose)(void *); int mainprog : 1; /* True if this is the main program */ int rtld : 1; /* True if this is the dynamic linker */ int textrel : 1; /* True if there are relocations to text seg */ int symbolic : 1; /* True if generated with "-Bsymbolic" */ int printed : 1; /* True if ldd has printed it */ struct link_map linkmap; /* for GDB */ } Obj_Entry; extern struct r_debug _rtld_debug; extern Obj_Entry *_rtld_objlist; extern Obj_Entry **_rtld_objtail; extern Obj_Entry _rtld_objself; extern Search_Path *_rtld_paths; extern bool _rtld_trust; extern const char *_rtld_error_message; /* rtld_start.S */ extern void _rtld_bind_start(void); /* rtld.c */ extern void _rtld_error(const char *, ...); extern void _rtld_die(void); extern char *_rtld_dlerror(void); extern void *_rtld_dlopen(const char *, int); extern void *_rtld_dlsym(void *, const char *); extern int _rtld_dlclose(void *); extern void _rtld_debug_state(void); extern void _rtld_linkmap_add(Obj_Entry *); extern void _rtld_linkmap_delete(Obj_Entry *); /* headers.c */ extern void _rtld_digest_dynamic(Obj_Entry *); extern Obj_Entry *_rtld_digest_phdr(const Elf_Phdr *, int, caddr_t); /* load.c */ extern Obj_Entry *_rtld_load_object(char *path); extern int _rtld_load_needed_objects(Obj_Entry *); /* path.c */ extern void _rtld_add_paths(Search_Path **, const char *); /* reloc.c */ extern int _rtld_do_copy_relocations(const Obj_Entry *); extern caddr_t _rtld_bind(const Obj_Entry *, Elf_Word); extern int _rtld_relocate_objects(Obj_Entry *, bool); /* search.c */ extern char *_rtld_find_library(const char *, const Obj_Entry *); /* symbol.c */ extern unsigned long _rtld_elf_hash(const char *); extern const Elf_Sym *_rtld_symlook_obj(const char *, unsigned long, const Obj_Entry *, bool); extern const Elf_Sym *_rtld_find_symdef(const Obj_Entry *, Elf_Word, const char *, const Obj_Entry *, const Obj_Entry **, bool); /* map_object.c */ extern Obj_Entry *_rtld_map_object(const char *, int); #endif /* } */