/*
* Process a shared object's DYNAMIC section, and save the important
* information in its Obj_Entry structure.
*/
void
_rtld_digest_dynamic(const char *execname, Obj_Entry *obj)
{
Elf_Dyn *dynp;
Needed_Entry **needed_tail = &obj->needed;
const Elf_Dyn *dyn_rpath = NULL;
bool use_pltrel = false;
bool use_pltrela = false;
Elf_Addr relsz = 0, relasz = 0;
Elf_Addr pltrel = 0, pltrelsz = 0;
Elf_Addr init = 0, fini = 0;
for (dynp = obj->dynamic; dynp->d_tag != DT_NULL; ++dynp) {
switch (dynp->d_tag) {
case DT_REL:
obj->rel = (const Elf_Rel *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_RELSZ:
relsz = dynp->d_un.d_val;
break;
case DT_RELENT:
assert(dynp->d_un.d_val == sizeof(Elf_Rel));
break;
case DT_JMPREL:
pltrel = dynp->d_un.d_ptr;
break;
case DT_PLTRELSZ:
pltrelsz = dynp->d_un.d_val;
break;
case DT_RELA:
obj->rela = (const Elf_Rela *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_RELASZ:
relasz = dynp->d_un.d_val;
break;
case DT_RELAENT:
assert(dynp->d_un.d_val == sizeof(Elf_Rela));
break;
case DT_PLTREL:
use_pltrel = dynp->d_un.d_val == DT_REL;
use_pltrela = dynp->d_un.d_val == DT_RELA;
assert(use_pltrel || use_pltrela);
break;
case DT_SYMTAB:
obj->symtab = (const Elf_Sym *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_SYMENT:
assert(dynp->d_un.d_val == sizeof(Elf_Sym));
break;
case DT_STRTAB:
obj->strtab = (const char *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_STRSZ:
obj->strsize = dynp->d_un.d_val;
break;
case DT_HASH:
{
const Elf_Symindx *hashtab = (const Elf_Symindx *)
(obj->relocbase + dynp->d_un.d_ptr);
if (hashtab[0] > UINT32_MAX)
obj->nbuckets = UINT32_MAX;
else
obj->nbuckets = hashtab[0];
obj->nchains = hashtab[1];
obj->buckets = hashtab + 2;
obj->chains = obj->buckets + obj->nbuckets;
/*
* Should really be in _rtld_relocate_objects,
* but _rtld_symlook_obj might be used before.
*/
if (obj->nbuckets) {
fast_divide32_prepare(obj->nbuckets,
&obj->nbuckets_m,
&obj->nbuckets_s1,
&obj->nbuckets_s2);
}
}
break;
case DT_NEEDED:
{
Needed_Entry *nep = NEW(Needed_Entry);
nep->name = dynp->d_un.d_val;
nep->obj = NULL;
nep->next = NULL;
*needed_tail = nep;
needed_tail = &nep->next;
}
break;
case DT_PLTGOT:
obj->pltgot = (Elf_Addr *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_TEXTREL:
obj->textrel = true;
break;
case DT_SYMBOLIC:
obj->symbolic = true;
break;
case DT_RPATH:
/*
* We have to wait until later to process this, because
* we might not have gotten the address of the string
* table yet.
*/
dyn_rpath = dynp;
break;
case DT_SONAME:
/* Not used by the dynamic linker. */
break;
case DT_INIT:
init = dynp->d_un.d_ptr;
break;
case DT_FINI:
fini = dynp->d_un.d_ptr;
break;
/*
* Don't process DT_DEBUG on MIPS as the dynamic section
* is mapped read-only. DT_MIPS_RLD_MAP is used instead.
* XXX: n32/n64 may use DT_DEBUG, not sure yet.
*/
#ifndef __mips__
case DT_DEBUG:
#ifdef RTLD_LOADER
dynp->d_un.d_ptr = (Elf_Addr)&_rtld_debug;
#endif
break;
#endif
#ifdef __mips__
case DT_MIPS_LOCAL_GOTNO:
obj->local_gotno = dynp->d_un.d_val;
break;
case DT_MIPS_SYMTABNO:
obj->symtabno = dynp->d_un.d_val;
break;
case DT_MIPS_GOTSYM:
obj->gotsym = dynp->d_un.d_val;
break;
case DT_MIPS_RLD_MAP:
#ifdef RTLD_LOADER
*((Elf_Addr *)(dynp->d_un.d_ptr)) = (Elf_Addr)
&_rtld_debug;
#endif
break;
#endif
#ifdef __powerpc__
case DT_PPC_GOT:
obj->gotptr = (Elf_Addr *)(obj->relocbase + dynp->d_un.d_ptr);
break;
#endif
case DT_FLAGS_1:
obj->z_now =
((dynp->d_un.d_val & DF_1_BIND_NOW) != 0);
obj->z_nodelete =
((dynp->d_un.d_val & DF_1_NODELETE) != 0);
obj->z_initfirst =
((dynp->d_un.d_val & DF_1_INITFIRST) != 0);
obj->z_noopen =
((dynp->d_un.d_val & DF_1_NOOPEN) != 0);
break;
}
}
obj->rellim = (const Elf_Rel *)((const uint8_t *)obj->rel + relsz);
obj->relalim = (const Elf_Rela *)((const uint8_t *)obj->rela + relasz);
if (use_pltrel) {
obj->pltrel = (const Elf_Rel *)(obj->relocbase + pltrel);
obj->pltrellim = (const Elf_Rel *)(obj->relocbase + pltrel + pltrelsz);
obj->pltrelalim = 0;
/* On PPC and SPARC, at least, REL(A)SZ may include JMPREL.
Trim rel(a)lim to save time later. */
if (obj->rellim && obj->pltrel &&
obj->rellim > obj->pltrel &&
obj->rellim <= obj->pltrellim)
obj->rellim = obj->pltrel;
} else if (use_pltrela) {
obj->pltrela = (const Elf_Rela *)(obj->relocbase + pltrel);
obj->pltrellim = 0;
obj->pltrelalim = (const Elf_Rela *)(obj->relocbase + pltrel + pltrelsz);
/* On PPC and SPARC, at least, REL(A)SZ may include JMPREL.
Trim rel(a)lim to save time later. */
if (obj->relalim && obj->pltrela &&
obj->relalim > obj->pltrela &&
obj->relalim <= obj->pltrelalim)
obj->relalim = obj->pltrela;
}
#if defined(RTLD_LOADER) && defined(__HAVE_FUNCTION_DESCRIPTORS)
if (init != 0)
obj->init = (void (*)(void))
_rtld_function_descriptor_alloc(obj, NULL, init);
if (fini != 0)
obj->fini = (void (*)(void))
_rtld_function_descriptor_alloc(obj, NULL, fini);
#else
if (init != 0)
obj->init = (void (*)(void))
(obj->relocbase + init);
if (fini != 0)
obj->fini = (void (*)(void))
(obj->relocbase + fini);
#endif
if (dyn_rpath != NULL) {
_rtld_add_paths(execname, &obj->rpaths, obj->strtab +
dyn_rpath->d_un.d_val);
}
}
/*
* Process a shared object's DYNAMIC section, and save the important
* information in its Obj_Entry structure.
*/
void
_rtld_digest_dynamic(const char *execname, Obj_Entry *obj)
{
Elf_Dyn *dynp;
Needed_Entry **needed_tail = &obj->needed;
const Elf_Dyn *dyn_soname = NULL;
const Elf_Dyn *dyn_rpath = NULL;
bool use_pltrel = false;
bool use_pltrela = false;
Elf_Addr relsz = 0, relasz = 0;
Elf_Addr pltrel = 0, pltrelsz = 0;
#ifdef RTLD_LOADER
Elf_Addr init = 0, fini = 0;
#endif
dbg(("headers: digesting PT_DYNAMIC at %p", obj->dynamic));
for (dynp = obj->dynamic; dynp->d_tag != DT_NULL; ++dynp) {
dbg((" d_tag %ld at %p", (long)dynp->d_tag, dynp));
switch (dynp->d_tag) {
case DT_REL:
obj->rel = (const Elf_Rel *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_RELSZ:
relsz = dynp->d_un.d_val;
break;
case DT_RELENT:
assert(dynp->d_un.d_val == sizeof(Elf_Rel));
break;
case DT_JMPREL:
pltrel = dynp->d_un.d_ptr;
break;
case DT_PLTRELSZ:
pltrelsz = dynp->d_un.d_val;
break;
case DT_RELA:
obj->rela = (const Elf_Rela *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_RELASZ:
relasz = dynp->d_un.d_val;
break;
case DT_RELAENT:
assert(dynp->d_un.d_val == sizeof(Elf_Rela));
break;
case DT_PLTREL:
use_pltrel = dynp->d_un.d_val == DT_REL;
use_pltrela = dynp->d_un.d_val == DT_RELA;
assert(use_pltrel || use_pltrela);
break;
case DT_SYMTAB:
obj->symtab = (const Elf_Sym *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_SYMENT:
assert(dynp->d_un.d_val == sizeof(Elf_Sym));
break;
case DT_STRTAB:
obj->strtab = (const char *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_STRSZ:
obj->strsize = dynp->d_un.d_val;
break;
case DT_VERNEED:
obj->verneed = (const Elf_Verneed *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_VERNEEDNUM:
obj->verneednum = dynp->d_un.d_val;
break;
case DT_VERDEF:
obj->verdef = (const Elf_Verdef *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_VERDEFNUM:
obj->verdefnum = dynp->d_un.d_val;
break;
case DT_VERSYM:
obj->versyms = (const Elf_Versym *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_HASH:
{
const Elf_Symindx *hashtab = (const Elf_Symindx *)
(obj->relocbase + dynp->d_un.d_ptr);
if (hashtab[0] > UINT32_MAX)
obj->nbuckets = UINT32_MAX;
else
obj->nbuckets = hashtab[0];
obj->nchains = hashtab[1];
obj->buckets = hashtab + 2;
obj->chains = obj->buckets + obj->nbuckets;
/*
* Should really be in _rtld_relocate_objects,
* but _rtld_symlook_obj might be used before.
*/
if (obj->nbuckets) {
fast_divide32_prepare(obj->nbuckets,
&obj->nbuckets_m,
&obj->nbuckets_s1,
&obj->nbuckets_s2);
}
}
break;
case DT_NEEDED:
{
Needed_Entry *nep = NEW(Needed_Entry);
nep->name = dynp->d_un.d_val;
nep->obj = NULL;
nep->next = NULL;
*needed_tail = nep;
needed_tail = &nep->next;
}
break;
case DT_PLTGOT:
obj->pltgot = (Elf_Addr *)
(obj->relocbase + dynp->d_un.d_ptr);
break;
case DT_TEXTREL:
obj->textrel = true;
break;
case DT_SYMBOLIC:
obj->symbolic = true;
break;
case DT_RPATH:
/*
* We have to wait until later to process this, because
* we might not have gotten the address of the string
* table yet.
*/
dyn_rpath = dynp;
break;
case DT_SONAME:
dyn_soname = dynp;
break;
case DT_INIT:
#ifdef RTLD_LOADER
init = dynp->d_un.d_ptr;
#endif
break;
#ifdef HAVE_INITFINI_ARRAY
case DT_INIT_ARRAY:
obj->init_array =
(Elf_Addr *)(obj->relocbase + dynp->d_un.d_ptr);
dbg(("headers: DT_INIT_ARRAY at %p",
obj->init_array));
break;
case DT_INIT_ARRAYSZ:
obj->init_arraysz = dynp->d_un.d_val / sizeof(fptr_t);
dbg(("headers: DT_INIT_ARRAYZ %zu",
obj->init_arraysz));
break;
#endif
case DT_FINI:
#ifdef RTLD_LOADER
fini = dynp->d_un.d_ptr;
#endif
break;
#ifdef HAVE_INITFINI_ARRAY
case DT_FINI_ARRAY:
obj->fini_array =
(Elf_Addr *)(obj->relocbase + dynp->d_un.d_ptr);
dbg(("headers: DT_FINI_ARRAY at %p",
obj->fini_array));
break;
case DT_FINI_ARRAYSZ:
obj->fini_arraysz = dynp->d_un.d_val / sizeof(fptr_t);
dbg(("headers: DT_FINI_ARRAYZ %zu",
obj->fini_arraysz));
break;
#endif
/*
* Don't process DT_DEBUG on MIPS as the dynamic section
* is mapped read-only. DT_MIPS_RLD_MAP is used instead.
* XXX: n32/n64 may use DT_DEBUG, not sure yet.
*/
#ifndef __mips__
case DT_DEBUG:
#ifdef RTLD_LOADER
dynp->d_un.d_ptr = (Elf_Addr)&_rtld_debug;
#endif
break;
#endif
#ifdef __mips__
case DT_MIPS_LOCAL_GOTNO:
obj->local_gotno = dynp->d_un.d_val;
break;
case DT_MIPS_SYMTABNO:
obj->symtabno = dynp->d_un.d_val;
break;
case DT_MIPS_GOTSYM:
obj->gotsym = dynp->d_un.d_val;
break;
case DT_MIPS_RLD_MAP:
#ifdef RTLD_LOADER
*((Elf_Addr *)(dynp->d_un.d_ptr)) = (Elf_Addr)
&_rtld_debug;
#endif
break;
#endif
#ifdef __powerpc__
#ifdef _LP64
case DT_PPC64_GLINK:
obj->glink = (Elf_Addr)(uintptr_t)obj->relocbase + dynp->d_un.d_ptr;
break;
#else
case DT_PPC_GOT:
obj->gotptr = (Elf_Addr *)(obj->relocbase + dynp->d_un.d_ptr);
break;
#endif
#endif
case DT_FLAGS_1:
obj->z_now =
((dynp->d_un.d_val & DF_1_BIND_NOW) != 0);
obj->z_nodelete =
((dynp->d_un.d_val & DF_1_NODELETE) != 0);
obj->z_initfirst =
((dynp->d_un.d_val & DF_1_INITFIRST) != 0);
obj->z_noopen =
((dynp->d_un.d_val & DF_1_NOOPEN) != 0);
break;
}
}
obj->rellim = (const Elf_Rel *)((const uint8_t *)obj->rel + relsz);
obj->relalim = (const Elf_Rela *)((const uint8_t *)obj->rela + relasz);
if (use_pltrel) {
obj->pltrel = (const Elf_Rel *)(obj->relocbase + pltrel);
obj->pltrellim = (const Elf_Rel *)(obj->relocbase + pltrel + pltrelsz);
obj->pltrelalim = 0;
/* On PPC and SPARC, at least, REL(A)SZ may include JMPREL.
Trim rel(a)lim to save time later. */
if (obj->rellim && obj->pltrel &&
obj->rellim > obj->pltrel &&
obj->rellim <= obj->pltrellim)
obj->rellim = obj->pltrel;
} else if (use_pltrela) {
obj->pltrela = (const Elf_Rela *)(obj->relocbase + pltrel);
obj->pltrellim = 0;
obj->pltrelalim = (const Elf_Rela *)(obj->relocbase + pltrel + pltrelsz);
/* On PPC and SPARC, at least, REL(A)SZ may include JMPREL.
Trim rel(a)lim to save time later. */
if (obj->relalim && obj->pltrela &&
obj->relalim > obj->pltrela &&
obj->relalim <= obj->pltrelalim)
obj->relalim = obj->pltrela;
}
#ifdef RTLD_LOADER
if (init != 0)
obj->init = (Elf_Addr) obj->relocbase + init;
if (fini != 0)
obj->fini = (Elf_Addr) obj->relocbase + fini;
#endif
if (dyn_rpath != NULL) {
_rtld_add_paths(execname, &obj->rpaths, obj->strtab +
dyn_rpath->d_un.d_val);
}
if (dyn_soname != NULL) {
_rtld_object_add_name(obj, obj->strtab +
dyn_soname->d_un.d_val);
}
}
/* ARGSUSED */
struct cdbr *
cdbr_open(const char *path, int flags)
{
uint8_t buf[40];
int fd;
struct cdbr *cdbr;
struct stat sb;
if ((fd = open(path, O_RDONLY)) == -1)
return NULL;
errno = EINVAL;
if (fstat(fd, &sb) == -1 ||
read(fd, buf, sizeof(buf)) != sizeof(buf) ||
memcmp(buf, "NBCDB\n\0\001", 8) ||
(cdbr = malloc(sizeof(*cdbr))) == NULL) {
close(fd);
return NULL;
}
cdbr->data_size = le32dec(buf + 24);
cdbr->entries = le32dec(buf + 28);
cdbr->entries_index = le32dec(buf + 32);
cdbr->seed = le32dec(buf + 36);
if (cdbr->data_size < 0x100)
cdbr->offset_size = 1;
else if (cdbr->data_size < 0x10000)
cdbr->offset_size = 2;
else
cdbr->offset_size = 4;
if (cdbr->entries_index < 0x100)
cdbr->index_size = 1;
else if (cdbr->entries_index < 0x10000)
cdbr->index_size = 2;
else
cdbr->index_size = 4;
cdbr->mmap_size = (size_t)sb.st_size;
#ifdef __minix
if(!(cdbr->mmap_base = malloc(cdbr->mmap_size))) {
free(cdbr);
return NULL;
}
if ((size_t)read(fd, cdbr->mmap_base, cdbr->mmap_size) != cdbr->mmap_size)
{
free(cdbr->mmap_base);
free(cdbr);
return NULL;
}
#else /* !__minix */
cdbr->mmap_base = mmap(NULL, cdbr->mmap_size, PROT_READ, MAP_FILE|MAP_SHARED, fd, 0);
#endif /* __minix */
close(fd);
if (cdbr->mmap_base == MAP_FAILED) {
free(cdbr);
return NULL;
}
cdbr->hash_base = cdbr->mmap_base + 40;
cdbr->offset_base = cdbr->hash_base + cdbr->entries_index * cdbr->index_size;
if (cdbr->entries_index * cdbr->index_size % cdbr->offset_size)
cdbr->offset_base += cdbr->offset_size -
cdbr->entries_index * cdbr->index_size % cdbr->offset_size;
cdbr->data_base = cdbr->offset_base + (cdbr->entries + 1) * cdbr->offset_size;
if (cdbr->hash_base < cdbr->mmap_base ||
cdbr->offset_base < cdbr->mmap_base ||
cdbr->data_base < cdbr->mmap_base ||
cdbr->data_base + cdbr->data_size < cdbr->mmap_base ||
cdbr->data_base + cdbr->data_size >
cdbr->mmap_base + cdbr->mmap_size ||
cdbr->entries == 0 || cdbr->entries_index == 0) {
errno = EINVAL;
cdbr_close(cdbr);
return NULL;
}
fast_divide32_prepare(cdbr->entries, &cdbr->entries_m,
&cdbr->entries_s1, &cdbr->entries_s2);
fast_divide32_prepare(cdbr->entries_index, &cdbr->entries_index_m,
&cdbr->entries_index_s1, &cdbr->entries_index_s2);
return cdbr;
}
struct cdbr *
cdbr_open_mem(void *base, size_t size, int flags,
void (*unmap)(void *, void *, size_t), void *cookie)
{
struct cdbr *cdbr;
uint8_t *buf = base;
if (size < 40 || memcmp(buf, "NBCDB\n\0\001", 8)) {
SET_ERRNO(EINVAL);
return NULL;
}
cdbr = malloc(sizeof(*cdbr));
cdbr->unmap = unmap;
cdbr->cookie = cookie;
cdbr->data_size = le32dec(buf + 24);
cdbr->entries = le32dec(buf + 28);
cdbr->entries_index = le32dec(buf + 32);
cdbr->seed = le32dec(buf + 36);
if (cdbr->data_size < 0x100)
cdbr->offset_size = 1;
else if (cdbr->data_size < 0x10000)
cdbr->offset_size = 2;
else
cdbr->offset_size = 4;
if (cdbr->entries_index < 0x100)
cdbr->index_size = 1;
else if (cdbr->entries_index < 0x10000)
cdbr->index_size = 2;
else
cdbr->index_size = 4;
cdbr->mmap_base = base;
cdbr->mmap_size = size;
cdbr->hash_base = cdbr->mmap_base + 40;
cdbr->offset_base = cdbr->hash_base + cdbr->entries_index * cdbr->index_size;
if (cdbr->entries_index * cdbr->index_size % cdbr->offset_size)
cdbr->offset_base += cdbr->offset_size -
cdbr->entries_index * cdbr->index_size % cdbr->offset_size;
cdbr->data_base = cdbr->offset_base + (cdbr->entries + 1) * cdbr->offset_size;
if (cdbr->hash_base < cdbr->mmap_base ||
cdbr->offset_base < cdbr->mmap_base ||
cdbr->data_base < cdbr->mmap_base ||
cdbr->data_base + cdbr->data_size < cdbr->mmap_base ||
cdbr->data_base + cdbr->data_size >
cdbr->mmap_base + cdbr->mmap_size) {
SET_ERRNO(EINVAL);
free(cdbr);
return NULL;
}
if (cdbr->entries) {
fast_divide32_prepare(cdbr->entries, &cdbr->entries_m,
&cdbr->entries_s1, &cdbr->entries_s2);
}
if (cdbr->entries_index) {
fast_divide32_prepare(cdbr->entries_index,
&cdbr->entries_index_m,
&cdbr->entries_index_s1, &cdbr->entries_index_s2);
}
return cdbr;
}
