/* $NetBSD: rtld.h,v 1.22 1999/12/15 05:22:37 christos 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 #include #include #include #include #include #include #include "rtldenv.h" #include "link.h" #if defined(_RTLD_SOURCE) #define RTLD_DEFAULT_LIBRARY_PATH "/usr/lib" #define _PATH_LD_HINTS "/etc/ld.so.conf" #if 0 #define SVR4_LIBDIR "/usr/lib" #endif #define LIBDIRLEN (sizeof LIBDIR - 1) #define SVR4_LIBDIRLEN (sizeof SVR4_LIBDIR - 1) #ifndef PAGESIZE # ifdef VARPSZ extern int _rtld_pagesz; # ifdef RTLD_DEBUG # define PAGESIZE (assert(_rtld_pagesz), _rtld_pagesz) # else # define PAGESIZE _rtld_pagesz # endif # else # ifndef __sparc__ # define PAGESIZE NBPG # else #error "Sparc has a variable page size" # endif # endif #endif #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))) #endif /* _RTLD_SOURCE */ /* * C++ has mandated the use of the following keywords for its new boolean * type. We might as well follow their lead. */ typedef enum { false = 0, true = 1 } bool; struct Struct_Obj_Entry; typedef struct Struct_Objlist_Entry { SIMPLEQ_ENTRY(Struct_Objlist_Entry) link; struct Struct_Obj_Entry *obj; } Objlist_Entry; typedef SIMPLEQ_HEAD(Struct_Objlist, Struct_Objlist_Entry) Objlist; 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; #define RTLD_MAX_ENTRY 10 #define RTLD_MAX_LIBRARY 4 #define RTLD_MAX_CTL 2 typedef struct _rtld_library_xform_t { struct _rtld_library_xform_t *next; char *name; int ctl[RTLD_MAX_CTL]; int ctltype[RTLD_MAX_CTL]; int ctlmax; struct { char *value; char *library[RTLD_MAX_LIBRARY]; } entry[RTLD_MAX_ENTRY]; } Library_Xform; /* * 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; /* Reloc const = mapbase - *vaddrbase */ Elf_Dyn *dynamic; /* Dynamic section */ caddr_t entry; /* Entry point */ const Elf_Phdr *phdr; /* Program header if mapped, ow 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 */ #if defined(__mips__) Elf_Word local_gotno; /* Number of local GOT entries */ Elf_Word symtabno; /* Number of dynamic symbols */ Elf_Word gotsym; /* First dynamic symbol in GOT */ #endif 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 (%) */ void (*init) /* Initialization function to call */ __P((void)); void (*fini) /* Termination function to call */ __P((void)); /* Entry points for dlopen() and friends. */ void *(*dlopen) __P((const char *, int)); void *(*dlsym) __P((void *, const char *)); char *(*dlerror) __P((void)); int (*dlclose) __P((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 */ /* These items are computed by map_object() or by digest_phdr(). */ const char *interp; /* Pathname of the interpreter, if any */ Objlist dldags; /* Object belongs to these dlopened DAGs (%) */ Objlist dagmembers; /* DAG has these members (%) */ dev_t dev; /* Object's filesystem's device */ ino_t ino; /* Object's inode number */ unsigned long mark; /* Set to "_rtld_curmark" to avoid repeat visits */ } Obj_Entry; #if defined(_RTLD_SOURCE) extern struct r_debug _rtld_debug; extern Search_Path *_rtld_default_paths; extern Obj_Entry *_rtld_objlist; extern Obj_Entry **_rtld_objtail; extern Obj_Entry *_rtld_objmain; extern Obj_Entry _rtld_objself; extern Search_Path *_rtld_paths; extern Library_Xform *_rtld_xforms; extern bool _rtld_trust; extern const char *_rtld_error_message; extern unsigned long _rtld_curmark; extern Objlist _rtld_list_global; extern Objlist _rtld_list_main; extern Elf_Sym _rtld_sym_zero; /* rtld_start.S */ void _rtld_bind_start __P((void)); /* rtld.c */ void _rtld_error __P((const char *, ...)); void _rtld_die __P((void)); char *_rtld_dlerror __P((void)); void *_rtld_dlopen __P((const char *, int)); void *_rtld_dlsym __P((void *, const char *)); int _rtld_dlclose __P((void *)); int _rtld_dladdr __P((const void *, Dl_info *)); void _rtld_debug_state __P((void)); void _rtld_linkmap_add __P((Obj_Entry *)); void _rtld_linkmap_delete __P((Obj_Entry *)); /* headers.c */ void _rtld_digest_dynamic __P((Obj_Entry *)); Obj_Entry *_rtld_digest_phdr __P((const Elf_Phdr *, int, caddr_t)); /* load.c */ Obj_Entry *_rtld_load_object __P((char *, bool)); int _rtld_load_needed_objects __P((Obj_Entry *, bool)); int _rtld_preload __P((const char *, bool)); /* path.c */ void _rtld_add_paths __P((Search_Path **, const char *, bool)); void _rtld_process_hints __P((Search_Path **, Library_Xform **, const char *, bool)); /* reloc.c */ int _rtld_do_copy_relocations __P((const Obj_Entry *, bool)); caddr_t _rtld_bind __P((Obj_Entry *, Elf_Word)); int _rtld_relocate_objects __P((Obj_Entry *, bool, bool)); int _rtld_relocate_nonplt_object __P((Obj_Entry *, const Elf_RelA *, bool)); int _rtld_relocate_plt_object __P((Obj_Entry *, const Elf_RelA *, caddr_t *, bool, bool)); /* search.c */ char *_rtld_find_library __P((const char *, const Obj_Entry *)); /* symbol.c */ unsigned long _rtld_elf_hash __P((const char *)); const Elf_Sym *_rtld_symlook_obj __P((const char *, unsigned long, const Obj_Entry *, bool)); const Elf_Sym *_rtld_find_symdef __P((const Obj_Entry *, Elf_Word, const char *, Obj_Entry *, const Obj_Entry **, bool)); const Elf_Sym *_rtld_symlook_list(const char *, unsigned long, Objlist *, const Obj_Entry **, bool in_plt); /* map_object.c */ Obj_Entry *_rtld_map_object __P((const char *, int, const struct stat *)); void _rtld_obj_free(Obj_Entry *); Obj_Entry *_rtld_obj_new(void); #if defined(__mips__) /* mips_reloc.c */ void _rtld_relocate_mips_got __P((Obj_Entry *)); caddr_t _rtld_bind_mips __P((Elf_Word, Elf_Addr, Elf_Addr, Elf_Addr)); #endif #if defined(__powerpc__) /* ppc_reloc.c */ caddr_t _rtld_bind_powerpc __P((Obj_Entry *, Elf_Word)); int _rtld_reloc_powerpc_plt __P((Obj_Entry *, const Elf_RelA *, bool)); void _rtld_setup_powerpc_plt __P((const Obj_Entry *)); #endif #endif /* _RTLD_SOURCE */ #endif /* RTLD_H */