diff options
Diffstat (limited to 'elf/dl-libc.c')
| -rw-r--r-- | elf/dl-libc.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/elf/dl-libc.c b/elf/dl-libc.c index 1810b13074..8fd98f08e7 100644 --- a/elf/dl-libc.c +++ b/elf/dl-libc.c @@ -96,6 +96,50 @@ do_dlclose (void *ptr) _dl_close ((struct link_map *) ptr); } +/* This code is to support __libc_dlopen from __libc_dlopen'ed shared + libraries. We need to ensure the statically linked __libc_dlopen + etc. functions are used instead of the dynamically loaded. */ +struct dl_open_hook +{ + void *(*dlopen_mode) (const char *name, int mode); + void *(*dlsym) (void *map, const char *name); + int (*dlclose) (void *map); +}; + +#ifdef SHARED +extern struct dl_open_hook *_dl_open_hook; +libc_hidden_proto (_dl_open_hook); +struct dl_open_hook *_dl_open_hook __attribute__((nocommon)); +libc_hidden_data_def (_dl_open_hook); +#else +static void +do_dlsym_private (void *ptr) +{ + lookup_t l; + struct r_found_version vers; + vers.name = "GLIBC_PRIVATE"; + vers.hidden = 1; + /* vers.hash = _dl_elf_hash (version); */ + vers.hash = 0x0963cf85; + /* FIXME: Shouldn't we use libc.so.6* here? */ + vers.filename = NULL; + + struct do_dlsym_args *args = (struct do_dlsym_args *) ptr; + args->ref = NULL; + l = _dl_lookup_versioned_symbol (args->name, args->map, + &args->ref, args->map->l_scope, + &vers, 0, 0); + args->loadbase = l; +} + +static struct dl_open_hook _dl_open_hook = + { + .dlopen_mode = __libc_dlopen_mode, + .dlsym = __libc_dlsym, + .dlclose = __libc_dlclose + }; +#endif + /* ... and these functions call dlerror_run. */ void * @@ -105,7 +149,29 @@ __libc_dlopen_mode (const char *name, int mode) args.name = name; args.mode = mode; +#ifdef SHARED + if (__builtin_expect (_dl_open_hook != NULL, 0)) + return _dl_open_hook->dlopen_mode (name, mode); return (dlerror_run (do_dlopen, &args) ? NULL : (void *) args.map); +#else + if (dlerror_run (do_dlopen, &args)) + return NULL; + + struct do_dlsym_args sargs; + sargs.map = args.map; + sargs.name = "_dl_open_hook"; + + if (! dlerror_run (do_dlsym_private, &sargs)) + { + struct dl_open_hook **hook + = (struct dl_open_hook **) + (DL_SYMBOL_ADDRESS (sargs.loadbase, sargs.ref)); + if (hook != NULL) + *hook = &_dl_open_hook; + } + + return (void *) args.map; +#endif } void * @@ -115,6 +181,10 @@ __libc_dlsym (void *map, const char *name) args.map = map; args.name = name; +#ifdef SHARED + if (__builtin_expect (_dl_open_hook != NULL, 0)) + return _dl_open_hook->dlsym (map, name); +#endif return (dlerror_run (do_dlsym, &args) ? NULL : (void *) (DL_SYMBOL_ADDRESS (args.loadbase, args.ref))); } @@ -122,6 +192,10 @@ __libc_dlsym (void *map, const char *name) int __libc_dlclose (void *map) { +#ifdef SHARED + if (__builtin_expect (_dl_open_hook != NULL, 0)) + return _dl_open_hook->dlclose (map); +#endif return dlerror_run (do_dlclose, map); } |