object.c revision 9aa23310b13612fb7817c242be9055ca53e8fe9b
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Object file dependent suport for ELF objects.
*/
#include "_synonyms.h"
#include <sys/mman.h>
#include <stdio.h>
#include <unistd.h>
#include <libelf.h>
#include <string.h>
#include <dlfcn.h>
#include <debug.h>
#include <libld.h>
#include "_rtld.h"
#include "_audit.h"
#include "_elf.h"
static Rt_map *olmp = 0;
static Ehdr dehdr = { { ELFMAG0, ELFMAG1, ELFMAG2, ELFMAG3,
M_CLASS, M_DATA }, 0, M_MACH, EV_CURRENT };
/*
* Process a relocatable object. The static object link map pointer is used as
* a flag to determine whether a concatenation is already in progress (ie. an
* LD_PRELOAD may specify a list of objects). The link map returned simply
* specifies an `object' flag which the caller can interpret and thus call
* elf_obj_fini() to complete the concatenation.
*/
static Rt_map *
elf_obj_init(Lm_list *lml, Aliste lmco, const char *name)
{
Ofl_desc * ofl;
/*
* Initialize an output file descriptor and the entrance criteria.
*/
if ((ofl = (Ofl_desc *)calloc(sizeof (Ofl_desc), 1)) == 0)
return (0);
ofl->ofl_dehdr = &dehdr;
ofl->ofl_flags = (FLG_OF_DYNAMIC | FLG_OF_SHAROBJ | FLG_OF_STRIP);
ofl->ofl_flags1 = (FLG_OF1_RELDYN | FLG_OF1_TEXTOFF | FLG_OF1_MEMORY);
ofl->ofl_lml = lml;
/*
* As ent_setup() will effectively lazy load the necessary support
* libraries, make sure ld.so.1 is initialized for plt relocations.
*/
if (elf_rtld_load() == 0)
return (0);
/*
* Configure libld.so to process objects of the desired target
* type (this is the first call to libld.so, which will effectively
* lazyload it).
*/
if (ld_init_target(lml, M_MACH) != 0)
return (0);
/*
* Obtain a generic set of entrance criteria
*/
if (ld_ent_setup(ofl, syspagsz) == S_ERROR)
return (0);
/*
* Generate a link map place holder and use the `rt_priv' element to
* maintain the output file descriptor.
*/
if ((olmp = (Rt_map *)calloc(sizeof (Rt_map), 1)) == 0)
return (0);
DBG_CALL(Dbg_file_elf(lml, name, 0, 0, 0, 0, lml->lm_lmidstr, lmco));
FLAGS(olmp) |= FLG_RT_OBJECT;
olmp->rt_priv = (void *)ofl;
/*
* Initialize string tables.
*/
if (ld_init_strings(ofl) == S_ERROR)
return (0);
/*
* Assign the output file name to be the initial object that got us
* here. This name is being used for diagnostic purposes only as we
* don't actually generate an output file unless debugging is enabled.
*/
ofl->ofl_name = name;
ORIGNAME(olmp) = PATHNAME(olmp) = NAME(olmp) = (char *)name;
LIST(olmp) = lml;
lm_append(lml, lmco, olmp);
return (olmp);
}
/*
* Initial processing of a relocatable object. If this is the first object
* encountered we need to initialize some structures, then simply call the
* link-edit functionality to provide the initial processing of the file (ie.
* reads in sections and symbols, performs symbol resolution if more that one
* object file have been specified, and assigns input sections to output
* sections).
*/
Rt_map *
elf_obj_file(Lm_list *lml, Aliste lmco, const char *name, int fd)
{
Rej_desc rej;
/*
* If this is the first relocatable object (LD_PRELOAD could provide a
* list of objects), initialize an input file descriptor and a link map.
*/
if (!olmp) {
/*
* Load the link-editor library.
*/
if ((olmp = elf_obj_init(lml, lmco, name)) == 0)
return (0);
}
/*
* Proceed to process the input file.
*/
DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD));
if (ld_process_open(name, name, &fd, (Ofl_desc *)olmp->rt_priv,
NULL, &rej) == (Ifl_desc *)S_ERROR)
return (0);
return (olmp);
}
/*
* Finish relocatable object processing. Having already initially processed one
* or more objects, complete the generation of a shared object image by calling
* the appropriate link-edit functionality (refer to sgs/ld/common/main.c).
*/
Rt_map *
elf_obj_fini(Lm_list *lml, Rt_map *lmp, int *in_nfavl)
{
Ofl_desc *ofl = (Ofl_desc *)lmp->rt_priv;
Rt_map *nlmp;
Addr etext;
Ehdr *ehdr;
Phdr *phdr;
Mmap *mmaps;
uint_t phnum, mmapcnt;
Lm_cntl *lmc;
DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD));
if (ld_reloc_init(ofl) == S_ERROR)
return (0);
if (ld_sym_validate(ofl) == S_ERROR)
return (0);
if (ld_make_sections(ofl) == S_ERROR)
return (0);
if (ld_create_outfile(ofl) == S_ERROR)
return (0);
if ((etext = ld_update_outfile(ofl)) == (Addr)S_ERROR)
return (0);
if (ld_reloc_process(ofl) == S_ERROR)
return (0);
/*
* At this point we have a memory image of the shared object. The link
* editor would normally simply write this to the required output file.
* If we're debugging generate a standard temporary output file.
*/
DBG_CALL(Dbg_file_output(ofl));
/*
* Allocate a mapping array to retain mapped segment information.
*/
ehdr = ofl->ofl_nehdr;
phdr = ofl->ofl_phdr;
if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0)
return (0);
for (mmapcnt = 0, phnum = 0; phnum < ehdr->e_phnum; phnum++) {
if (phdr[phnum].p_type != PT_LOAD)
continue;
mmaps[mmapcnt].m_vaddr = (caddr_t)
(phdr[phnum].p_vaddr + (ulong_t)ehdr);
mmaps[mmapcnt].m_msize = phdr[phnum].p_memsz;
mmaps[mmapcnt].m_fsize = phdr[phnum].p_filesz;
mmaps[mmapcnt].m_perm = (PROT_READ | PROT_WRITE | PROT_EXEC);
mmapcnt++;
}
/*
* Generate a new link map representing the memory image created.
*/
if ((nlmp = elf_new_lm(lml, ofl->ofl_name, ofl->ofl_name,
ofl->ofl_osdynamic->os_outdata->d_buf, (ulong_t)ehdr,
(ulong_t)ehdr + etext, CNTL(olmp), (ulong_t)ofl->ofl_size,
0, 0, 0, mmaps, mmapcnt, in_nfavl)) == 0)
return (0);
/*
* Remove this link map from the end of the link map list and copy its
* contents into the link map originally created for this file (we copy
* the contents rather than manipulate the link map pointers as parts
* of the dlopen code have remembered the original link map address).
*/
NEXT((Rt_map *)PREV(nlmp)) = 0;
/* LINTED */
lmc = (Lm_cntl *)alist_item_by_offset(lml->lm_lists, CNTL(nlmp));
lmc->lc_tail = (Rt_map *)PREV(nlmp);
if (CNTL(nlmp) == ALIST_OFF_DATA)
lml->lm_tail = (Rt_map *)PREV(nlmp);
lml->lm_obj--;
PREV(nlmp) = PREV(olmp);
NEXT(nlmp) = NEXT(olmp);
HANDLES(nlmp) = HANDLES(olmp);
GROUPS(nlmp) = GROUPS(olmp);
STDEV(nlmp) = STDEV(olmp);
STINO(nlmp) = STINO(olmp);
FLAGS(nlmp) |= ((FLAGS(olmp) & ~FLG_RT_OBJECT) | FLG_RT_IMGALLOC);
FLAGS1(nlmp) |= FLAGS1(olmp);
MODE(nlmp) |= MODE(olmp);
NAME(nlmp) = NAME(olmp);
PATHNAME(nlmp) = PATHNAME(olmp);
ORIGNAME(nlmp) = ORIGNAME(olmp);
DIRSZ(nlmp) = DIRSZ(olmp);
ld_ofl_cleanup(ofl);
free(olmp->rt_priv);
(void) memcpy(olmp, nlmp, sizeof (Rt_map));
free(nlmp);
nlmp = olmp;
olmp = 0;
/*
* Now that we've allocated our permanent Rt_map structure, expand the
* PATHNAME() and insert it into the FullpathNode AVL tree
*/
if (FLAGS1(nlmp) & FL1_RT_RELATIVE)
(void) fullpath(nlmp, 0);
if (fpavl_insert(lml, nlmp, PATHNAME(nlmp), 0) == 0)
return (0);
/*
* If we're being audited tell the audit library of the file we've just
* opened.
*/
if ((lml->lm_tflags | FLAGS1(nlmp)) & LML_TFLG_AUD_MASK) {
if (audit_objopen(lmp, lmp) == 0)
return (0);
}
return (nlmp);
}