diff options
Diffstat (limited to 'elf/dl-libc.c')
| -rw-r--r-- | elf/dl-libc.c | 73 |
1 files changed, 72 insertions, 1 deletions
diff --git a/elf/dl-libc.c b/elf/dl-libc.c index c6818e0313..fc01f5514d 100644 --- a/elf/dl-libc.c +++ b/elf/dl-libc.c @@ -20,6 +20,7 @@ #include <dlfcn.h> #include <stdlib.h> #include <ldsodefs.h> +#include <dl-hash.h> extern int __libc_argc attribute_hidden; extern char **__libc_argv attribute_hidden; @@ -78,6 +79,15 @@ struct do_dlsym_args const ElfW(Sym) *ref; }; +struct do_dlvsym_args +{ + /* dlvsym is like dlsym. */ + struct do_dlsym_args dlsym; + + /* But dlvsym needs a version as well. */ + struct r_found_version version; +}; + static void do_dlopen (void *ptr) { @@ -99,6 +109,18 @@ do_dlsym (void *ptr) } static void +do_dlvsym (void *ptr) +{ + struct do_dlvsym_args *args = ptr; + args->dlsym.ref = NULL; + args->dlsym.loadbase + = GLRO(dl_lookup_symbol_x) (args->dlsym.name, args->dlsym.map, + &args->dlsym.ref, + args->dlsym.map->l_local_scope, + &args->version, 0, 0, NULL); +} + +static void do_dlclose (void *ptr) { GLRO(dl_close) ((struct link_map *) ptr); @@ -112,6 +134,7 @@ struct dl_open_hook void *(*dlopen_mode) (const char *name, int mode); void *(*dlsym) (void *map, const char *name); int (*dlclose) (void *map); + void *(*dlvsym) (void *map, const char *name, const char *version); }; #ifdef SHARED @@ -119,6 +142,15 @@ 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); + +/* The dlvsym member was added retroactively to struct dl_open_hook. + Static applications which have it will set _dl_open_hook2 in + addition to _dl_open_hook. */ +extern struct dl_open_hook *_dl_open_hook2; +libc_hidden_proto (_dl_open_hook2); +struct dl_open_hook *_dl_open_hook2 __attribute__ ((nocommon)); +libc_hidden_data_def (_dl_open_hook2); + #else static void do_dlsym_private (void *ptr) @@ -142,7 +174,8 @@ static struct dl_open_hook _dl_open_hook = { .dlopen_mode = __libc_dlopen_mode, .dlsym = __libc_dlsym, - .dlclose = __libc_dlclose + .dlclose = __libc_dlclose, + .dlvsym = __libc_dlvsym, }; #endif @@ -192,6 +225,11 @@ __libc_register_dl_open_hook (struct link_map *map) hook = (struct dl_open_hook **) __libc_dlsym_private (map, "_dl_open_hook"); if (hook != NULL) *hook = &_dl_open_hook; + + /* For dlvsym support. */ + hook = (struct dl_open_hook **) __libc_dlsym_private (map, "_dl_open_hook2"); + if (hook != NULL) + *hook = &_dl_open_hook; } #endif @@ -211,6 +249,39 @@ __libc_dlsym (void *map, const char *name) } libc_hidden_def (__libc_dlsym) +/* Replacement for dlvsym. MAP must be a real map. This function + returns NULL without setting the dlerror value in case of static + dlopen from an old binary. */ +void * +__libc_dlvsym (void *map, const char *name, const char *version) +{ +#ifdef SHARED + if (!rtld_active ()) + { + /* The static application is too old and does not provide the + dlvsym hook. */ + if (_dl_open_hook2 == NULL) + return NULL; + return _dl_open_hook2->dlvsym (map, name, version); + } +#endif + + struct do_dlvsym_args args; + args.dlsym.map = map; + args.dlsym.name = name; + + /* See _dl_vsym in dl-sym.c. */ + args.version.name = version; + args.version.hidden = 1; + args.version.hash = _dl_elf_hash (version); + args.version.filename = NULL; + + return (dlerror_run (do_dlvsym, &args) ? NULL + : (void *) (DL_SYMBOL_ADDRESS (args.dlsym.loadbase, + args.dlsym.ref))); +} +libc_hidden_def (__libc_dlvsym) + int __libc_dlclose (void *map) { |