/* Various symbol table handling functions, including symbol lookup */
-
-/*
- * This is the start of the linked list that describes all of the files present
- * in the system with pointers to all of the symbol, string, and hash tables,
- * as well as all of the other good stuff in the binary.
- */
-struct elf_resolve *_dl_loaded_modules = NULL;
-
/*
* This is the list of modules that are loaded when the image is first
* started. As we add more via dlopen, they get added into other
/* This is the new hash function that is used by the ELF linker to generate the
* GNU hash table that each executable and library will have if --hash-style=[gnu,both]
* is passed to the linker. We need it to decode the GNU hash table. */
-static inline Elf_Symndx _dl_gnu_hash (const unsigned char *name)
+static __inline__ Elf_Symndx _dl_gnu_hash (const unsigned char *name)
{
unsigned long h = 5381;
unsigned char c;
/* This is the hash function that is used by the ELF linker to generate the
* hash table that each executable and library is required to have. We need
* it to decode the hash table. */
-static inline Elf_Symndx _dl_elf_hash(const unsigned char *name)
+static __inline__ Elf_Symndx _dl_elf_hash(const unsigned char *name)
{
unsigned long hash=0;
unsigned long tmp;
struct elf_resolve *tpnt;
int i;
- if (!_dl_loaded_modules) {
- tpnt = _dl_loaded_modules = (struct elf_resolve *) _dl_malloc(sizeof(struct elf_resolve));
- _dl_memset(tpnt, 0, sizeof(struct elf_resolve));
- } else {
- tpnt = _dl_loaded_modules;
- while (tpnt->next)
- tpnt = tpnt->next;
- tpnt->next = (struct elf_resolve *) _dl_malloc(sizeof(struct elf_resolve));
- _dl_memset(tpnt->next, 0, sizeof(struct elf_resolve));
- tpnt->next->prev = tpnt;
- tpnt = tpnt->next;
- };
+ tpnt = _dl_malloc(sizeof(struct elf_resolve));
+ _dl_memset(tpnt, 0, sizeof(struct elf_resolve));
+
+ if (!_dl_loaded_modules)
+ _dl_loaded_modules = tpnt;
+ else {
+ struct elf_resolve *t = _dl_loaded_modules;
+ while (t->next)
+ t = t->next;
+ t->next = tpnt;
+ t->next->prev = t;
+ tpnt = t->next;
+ }
tpnt->next = NULL;
tpnt->init_flag = 0;
tpnt->libname = _dl_strdup(libname);
tpnt->dynamic_addr = (ElfW(Dyn) *)dynamic_addr;
tpnt->libtype = loaded_file;
-
+
#ifdef __LDSO_GNU_HASH_SUPPORT__
if (dynamic_info[DT_GNU_HASH_IDX] != 0) {
-
- Elf32_Word *hash32 = (Elf_Symndx*)dynamic_info[DT_GNU_HASH_IDX];
-
- tpnt->nbucket = *hash32++;
- Elf32_Word symbias = *hash32++;
- Elf32_Word bitmask_nwords = *hash32++;
- /* Must be a power of two. */
- _dl_assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0);
- tpnt->l_gnu_bitmask_idxbits = bitmask_nwords - 1;
- tpnt->l_gnu_shift = *hash32++;
-
- tpnt->l_gnu_bitmask = (ElfW(Addr) *) hash32;
- hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords;
-
- tpnt->l_gnu_buckets = hash32;
- hash32 += tpnt->nbucket;
- tpnt->l_gnu_chain_zero = hash32 - symbias;
+ Elf32_Word *hash32 = (Elf_Symndx*)dynamic_info[DT_GNU_HASH_IDX];
+
+ tpnt->nbucket = *hash32++;
+ Elf32_Word symbias = *hash32++;
+ Elf32_Word bitmask_nwords = *hash32++;
+ /* Must be a power of two. */
+ _dl_assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0);
+ tpnt->l_gnu_bitmask_idxbits = bitmask_nwords - 1;
+ tpnt->l_gnu_shift = *hash32++;
+
+ tpnt->l_gnu_bitmask = (ElfW(Addr) *) hash32;
+ hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords;
+
+ tpnt->l_gnu_buckets = hash32;
+ hash32 += tpnt->nbucket;
+ tpnt->l_gnu_chain_zero = hash32 - symbias;
} else
/* Fall using old SysV hash table if GNU hash is not present */
#endif
/* Routine to check whether the symbol matches. */
static __attribute_noinline__ const ElfW(Sym) *
-check_match (const ElfW(Sym) *sym, char *strtab, const char* undef_name, int type_class) {
-
- if (type_class & (sym->st_shndx == SHN_UNDEF))
- /* undefined symbol itself */
- return NULL;
-
- if (sym->st_value == 0)
- /* No value */
- return NULL;
-
- if (ELF_ST_TYPE(sym->st_info) > STT_FUNC
- && ELF_ST_TYPE(sym->st_info) != STT_COMMON)
- /* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC
- * and STT_COMMON entries since these are no
- * code/data definitions
- */
- return NULL;
-
- if (_dl_strcmp(strtab + sym->st_name, undef_name) != 0)
- return NULL;
-
- /* This is the matching symbol */
- return sym;
+check_match (const ElfW(Sym) *sym, char *strtab, const char* undef_name, int type_class)
+{
+
+#if defined(USE_TLS) && USE_TLS
+ if ((sym->st_value == 0 && (ELF_ST_TYPE(sym->st_info) != STT_TLS))
+ || (type_class & (sym->st_shndx == SHN_UNDEF)))
+ /* No value or undefined symbol itself */
+ return NULL;
+
+ if (ELF_ST_TYPE(sym->st_info) > STT_FUNC
+ && ELF_ST_TYPE(sym->st_info) != STT_COMMON
+ && ELF_ST_TYPE(sym->st_info) != STT_TLS)
+ /* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC and STT_COMMON
+ * entries (and STT_TLS if TLS is supported) since these
+ * are no code/data definitions.
+ */
+ return NULL;
+#else
+ if (type_class & (sym->st_shndx == SHN_UNDEF))
+ /* undefined symbol itself */
+ return NULL;
+
+ if (sym->st_value == 0)
+ /* No value */
+ return NULL;
+
+ if (ELF_ST_TYPE(sym->st_info) > STT_FUNC
+ && ELF_ST_TYPE(sym->st_info) != STT_COMMON)
+ /* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC
+ * and STT_COMMON entries since these are no
+ * code/data definitions
+ */
+ return NULL;
+#endif
+#ifdef ARCH_SKIP_RELOC
+ if (ARCH_SKIP_RELOC(type_class, sym))
+ return NULL;
+#endif
+ if (_dl_strcmp(strtab + sym->st_name, undef_name) != 0)
+ return NULL;
+
+ /* This is the matching symbol */
+ return sym;
}
#ifdef __LDSO_GNU_HASH_SUPPORT__
-static __always_inline const ElfW(Sym) *
-_dl_lookup_gnu_hash(struct elf_resolve *tpnt, ElfW(Sym) *symtab, unsigned long hash,
- const char* undef_name, int type_class) {
-
+static __always_inline const ElfW(Sym) *
+_dl_lookup_gnu_hash(struct elf_resolve *tpnt, ElfW(Sym) *symtab, unsigned long hash,
+ const char* undef_name, int type_class)
+{
Elf_Symndx symidx;
const ElfW(Sym) *sym;
char *strtab;
-
+
const ElfW(Addr) *bitmask = tpnt->l_gnu_bitmask;
- ElfW(Addr) bitmask_word = bitmask[(hash / __ELF_NATIVE_CLASS) & tpnt->l_gnu_bitmask_idxbits];
+ ElfW(Addr) bitmask_word = bitmask[(hash / __ELF_NATIVE_CLASS) & tpnt->l_gnu_bitmask_idxbits];
unsigned int hashbit1 = hash & (__ELF_NATIVE_CLASS - 1);
unsigned int hashbit2 = ((hash >> tpnt->l_gnu_shift) & (__ELF_NATIVE_CLASS - 1));
-
_dl_assert (bitmask != NULL);
if (unlikely((bitmask_word >> hashbit1) & (bitmask_word >> hashbit2) & 1)) {
-
- Elf32_Word bucket = tpnt->l_gnu_buckets[hash % tpnt->nbucket];
-
+ unsigned long rem;
+ Elf32_Word bucket;
+
+ do_rem (rem, hash, tpnt->nbucket);
+ bucket = tpnt->l_gnu_buckets[rem];
+
if (bucket != 0) {
const Elf32_Word *hasharr = &tpnt->l_gnu_chain_zero[bucket];
do {
}
#endif
-static __always_inline const ElfW(Sym) *
-_dl_lookup_sysv_hash(struct elf_resolve *tpnt, ElfW(Sym) *symtab, unsigned long hash, const char* undef_name, int type_class) {
-
+static __always_inline const ElfW(Sym) *
+_dl_lookup_sysv_hash(struct elf_resolve *tpnt, ElfW(Sym) *symtab, unsigned long hash, const char* undef_name, int type_class)
+{
unsigned long hn;
char *strtab;
const ElfW(Sym) *sym;
Elf_Symndx symidx;
-
+
/* Avoid calling .urem here. */
do_rem(hn, hash, tpnt->nbucket);
strtab = (char *) (tpnt->dynamic_info[DT_STRTAB]);
-
+
_dl_assert(tpnt->elf_buckets != NULL);
-
+
for (symidx = tpnt->elf_buckets[hn]; symidx != STN_UNDEF; symidx = tpnt->chains[symidx]) {
sym = check_match (&symtab[symidx], strtab, undef_name, type_class);
if (sym != NULL)
}
/* No symbol found into the current module*/
return NULL;
-}
+}
/*
* This function resolves externals, and this is either called when we process
* relocations or when we call an entry in the PLT table for the first time.
*/
-char *_dl_find_hash(const char *name, struct dyn_elf *rpnt, struct elf_resolve *mytpnt, int type_class)
+char *_dl_find_hash(const char *name, struct r_scope_elem *scope, struct elf_resolve *mytpnt,
+ int type_class, struct symbol_ref *sym_ref)
{
struct elf_resolve *tpnt = NULL;
ElfW(Sym) *symtab;
+ int i = 0;
unsigned long elf_hash_number = 0xffffffff;
const ElfW(Sym) *sym = NULL;
char *weak_result = NULL;
+ struct r_scope_elem *loop_scope;
#ifdef __LDSO_GNU_HASH_SUPPORT__
unsigned long gnu_hash_number = _dl_gnu_hash((const unsigned char *)name);
#endif
-
- for (; rpnt; rpnt = rpnt->next) {
- tpnt = rpnt->dyn;
-
- if (!(tpnt->rtld_flags & RTLD_GLOBAL) && mytpnt) {
- if (mytpnt == tpnt)
- ;
- else {
- struct init_fini_list *tmp;
-
- for (tmp = mytpnt->rtld_local; tmp; tmp = tmp->next) {
- if (tmp->tpnt == tpnt)
- break;
+
+ if ((sym_ref) && (sym_ref->sym) && (ELF32_ST_VISIBILITY(sym_ref->sym->st_other) == STV_PROTECTED)) {
+ sym = sym_ref->sym;
+ if (mytpnt)
+ tpnt = mytpnt;
+ } else
+ for (loop_scope = scope; loop_scope && !sym; loop_scope = loop_scope->next) {
+ for (i = 0; i < loop_scope->r_nlist; i++) {
+ tpnt = loop_scope->r_list[i];
+
+ if (!(tpnt->rtld_flags & RTLD_GLOBAL) && mytpnt) {
+ if (mytpnt == tpnt)
+ ;
+ else {
+ struct init_fini_list *tmp;
+
+ for (tmp = mytpnt->rtld_local; tmp; tmp = tmp->next) {
+ if (tmp->tpnt == tpnt)
+ break;
+ }
+ if (!tmp)
+ continue;
}
- if (!tmp)
- continue;
}
- }
- /* Don't search the executable when resolving a copy reloc. */
- if ((type_class & ELF_RTYPE_CLASS_COPY) && tpnt->libtype == elf_executable)
- continue;
+ /* Don't search the executable when resolving a copy reloc. */
+ if ((type_class & ELF_RTYPE_CLASS_COPY) && tpnt->libtype == elf_executable)
+ continue;
- /* If the hash table is empty there is nothing to do here. */
- if (tpnt->nbucket == 0)
- continue;
+ /* If the hash table is empty there is nothing to do here. */
+ if (tpnt->nbucket == 0)
+ continue;
+
+ symtab = (ElfW(Sym) *) (intptr_t) (tpnt->dynamic_info[DT_SYMTAB]);
- symtab = (ElfW(Sym) *) (intptr_t) (tpnt->dynamic_info[DT_SYMTAB]);
-
#ifdef __LDSO_GNU_HASH_SUPPORT__
- /* Prefer GNU hash style, if any */
- if(tpnt->l_gnu_bitmask) {
- if((sym = _dl_lookup_gnu_hash(tpnt, symtab, gnu_hash_number, name, type_class)) != NULL)
- /* If sym has been found, do not search further */
- break;
- } else {
-#endif
- /* Use the old SysV-style hash table */
-
- /* Calculate the old sysv hash number only once */
- if(elf_hash_number == 0xffffffff)
- elf_hash_number = _dl_elf_hash((const unsigned char *)name);
-
- if((sym = _dl_lookup_sysv_hash(tpnt, symtab, elf_hash_number, name, type_class)) != NULL )
- break;
-#ifdef __LDSO_GNU_HASH_SUPPORT__
- }
-#endif
- } /* end of for (; rpnt; rpnt = rpnt->next) { */
+ /* Prefer GNU hash style, if any */
+ if (tpnt->l_gnu_bitmask) {
+ sym = _dl_lookup_gnu_hash(tpnt, symtab, gnu_hash_number, name, type_class);
+ if (sym != NULL)
+ /* If sym has been found, do not search further */
+ break;
+ } else {
+#endif
+ /* Use the old SysV-style hash table */
+
+ /* Calculate the old sysv hash number only once */
+ if (elf_hash_number == 0xffffffff)
+ elf_hash_number = _dl_elf_hash((const unsigned char *)name);
+
+ sym = _dl_lookup_sysv_hash(tpnt, symtab, elf_hash_number, name, type_class);
+ if (sym != NULL)
+ /* If sym has been found, do not search further */
+ break;
+#ifdef __LDSO_GNU_HASH_SUPPORT__
+ }
+#endif
+ } /* End of inner for */
+ }
- if(sym) {
+ if (sym) {
+ if (sym_ref) {
+ sym_ref->sym = sym;
+ sym_ref->tpnt = tpnt;
+ }
/* At this point we have found the requested symbol, do binding */
+#if defined(USE_TLS) && USE_TLS
+ if (ELF_ST_TYPE(sym->st_info) == STT_TLS) {
+ _dl_assert(sym_ref != NULL);
+ sym_ref->tpnt = tpnt;
+ return (char *)sym->st_value;
+ }
+#endif
+
switch (ELF_ST_BIND(sym->st_info)) {
case STB_WEAK:
#if 0
-/* Perhaps we should support old style weak symbol handling
- * per what glibc does when you export LD_DYNAMIC_WEAK */
+ /* Perhaps we should support old style weak symbol handling
+ * per what glibc does when you export LD_DYNAMIC_WEAK */
if (!weak_result)
- weak_result = (char *) DL_RELOC_ADDR(tpnt->loadaddr, sym->st_value);
+ weak_result = (char *)DL_FIND_HASH_VALUE(tpnt, type_class, sym);
break;
#endif
case STB_GLOBAL:
- return (char*) DL_RELOC_ADDR(tpnt->loadaddr, sym->st_value);
+#ifdef __FDPIC__
+ if (sym_ref)
+ sym_ref->tpnt = tpnt;
+#endif
+ return (char *)DL_FIND_HASH_VALUE(tpnt, type_class, sym);
default: /* Local symbols not handled here */
break;
}
}
+#ifdef __FDPIC__
+ if (sym_ref)
+ sym_ref->tpnt = tpnt;
+#endif
return weak_result;
}