OpenSolaris_b135/lib/libtnfctl/traverse.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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 (c) 1994, by Sun Microsytems, Inc.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Generic functions that know how to traverse elf sections in an object.
* Also functions that know how to traverse records in a section.
*
*/
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/procfs.h>
#include <sys/stat.h>
#include "tnfctl_int.h"
#include "dbg.h"
/*
* _tnfctl_traverse_object() - traverses all of the elf sections in an object,
* calling the supplied function on each.
*/
tnfctl_errcode_t
_tnfctl_traverse_object(int objfd, uintptr_t addr,
tnfctl_elf_search_t *search_info_p)
{
Elf *elf;
GElf_Ehdr *ehdr, ehdr_obj;
char *strs;
GElf_Shdr *shdr, shdr_obj;
Elf_Data *data;
u_int idx;
tnfctl_errcode_t prexstat = TNFCTL_ERR_NONE;
DBG_TNF_PROBE_1(_tnfctl_traverse_object_1, "libtnfctl",
"sunw%verbosity 3",
tnf_opaque, obj_addr, addr);
if (elf_version(EV_CURRENT) == EV_NONE)
return (TNFCTL_ERR_INTERNAL);
/* open elf descriptor on the fd */
elf = elf_begin(objfd, ELF_C_READ, NULL);
if (elf == NULL || elf_kind(elf) != ELF_K_ELF) {
DBG_TNF_PROBE_0(_tnfctl_traverse_object_2, "libtnfctl",
"sunw%verbosity 3; sunw%debug 'not elf object'");
return (TNFCTL_ERR_INTERNAL);
}
/* get the elf header */
if ((ehdr = gelf_getehdr(elf, &ehdr_obj)) == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_object: gelf_getehdr failed\n"));
(void) elf_end(elf);
return (TNFCTL_ERR_INTERNAL);
}
if ((ehdr->e_type != ET_EXEC) && (ehdr->e_type != ET_DYN)) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_object: not an "
"executable or a shared object\n"));
(void) elf_end(elf);
return (TNFCTL_ERR_INTERNAL);
}
/* if an executable file, the base address is 0 */
if (ehdr->e_type == ET_EXEC)
addr = 0;
/* get a pointer to the elf header string table */
strs = elf_strptr(elf, ehdr->e_shstrndx, NULL);
DBG_TNF_PROBE_1(_tnfctl_traverse_object_3, "libtnfctl",
"sunw%verbosity 3",
tnf_long, num_sections_found, ehdr->e_shnum);
for (idx = 1; idx < ehdr->e_shnum; idx++) {
Elf_Scn *scn;
if ((scn = elf_getscn(elf, idx)) == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_object: elf_getscn failed\n"));
prexstat = TNFCTL_ERR_INTERNAL;
break;
}
if ((shdr = gelf_getshdr(scn, &shdr_obj)) == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_obj:gelf_getshdr failed\n"));
prexstat = TNFCTL_ERR_INTERNAL;
break;
}
if ((data = elf_getdata(scn, NULL)) == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_obj:gelf_getdata failed\n"));
prexstat = TNFCTL_ERR_INTERNAL;
break;
}
/* call the supplied function */
prexstat = search_info_p->section_func(elf,
strs, scn, shdr, data, addr, search_info_p);
if (prexstat)
break;
}
(void) elf_end(elf);
return (prexstat);
} /* end _tnfctl_traverse_object */
/*
* _tnfctl_traverse_rela() - this function traverses a .rela section calling the
* supplied function on each relocation record.
*/
/*ARGSUSED*/
tnfctl_errcode_t
_tnfctl_traverse_rela(Elf * elf, char *strs, Elf_Scn * rel_scn,
GElf_Shdr * rel_shdr, Elf_Data * rel_data, uintptr_t baseaddr,
tnfctl_elf_search_t * search_info_p)
{
Elf_Scn *sym_scn;
GElf_Shdr *sym_shdr, sym_shdr_obj;
Elf_Data *sym_data;
Elf3264_Sym *sym_table;
Elf_Scn *str_scn;
GElf_Shdr *str_shdr, str_shdr_obj;
Elf_Data *str_data;
char *str_table;
ulong_t nrels;
uint_t i;
boolean_t isrela;
size_t rela_sz;
char *ptr;
DBG_TNF_PROBE_0(_tnfctl_traverse_rela_1, "libtnfctl",
"sunw%verbosity 4");
/* bail if this isn't a rela (or rel) section */
if (rel_shdr->sh_type == SHT_RELA) {
isrela = B_TRUE;
} else if (rel_shdr->sh_type == SHT_REL) {
isrela = B_FALSE;
} else
return (TNFCTL_ERR_NONE);
/* find the symbol table section associated with this rela section */
sym_scn = elf_getscn(elf, rel_shdr->sh_link);
if (sym_scn == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_rela:elf_getscn (sym) failed\n"));
return (TNFCTL_ERR_INTERNAL);
}
sym_shdr = gelf_getshdr(sym_scn, &sym_shdr_obj);
if (sym_shdr == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_rela:gelf_getshdr (sym) failed\n"));
return (TNFCTL_ERR_INTERNAL);
}
sym_data = elf_getdata(sym_scn, NULL);
if (sym_data == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_rela:elf_getdata (sym) failed\n"));
return (TNFCTL_ERR_INTERNAL);
}
sym_table = (Elf3264_Sym *) sym_data->d_buf;
/* find the string table associated with the symbol table */
str_scn = elf_getscn(elf, sym_shdr->sh_link);
if (str_scn == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_rela:elf_getscn (str) failed\n"));
return (TNFCTL_ERR_INTERNAL);
}
str_shdr = gelf_getshdr(str_scn, &str_shdr_obj);
if (str_shdr == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_rela:gelf_getshdr (str) failed\n"));
return (TNFCTL_ERR_INTERNAL);
}
str_data = elf_getdata(str_scn, NULL);
if (str_data == NULL) {
DBG((void) fprintf(stderr,
"_tnfctl_traverse_rela: elf_getdata (str) failed\n"));
return (TNFCTL_ERR_INTERNAL);
}
str_table = (char *) str_data->d_buf;
/* loop over each relocation record */
nrels = rel_shdr->sh_size / rel_shdr->sh_entsize;
DBG_TNF_PROBE_1(_tnfctl_traverse_rela_2, "libtnfctl",
"sunw%verbosity 3",
tnf_long, relocations_found, nrels);
ptr = rel_data->d_buf;
rela_sz = (isrela) ? sizeof (Elf3264_Rela) : sizeof (Elf3264_Rel);
for (i = 0; i < nrels; i++, ptr += rela_sz) {
Elf3264_Word syminfo;
Elf3264_Sym *sym;
Elf3264_Addr offset;
char *name;
uintptr_t addr;
tnfctl_errcode_t prexstat;
/* decode the r_info field of the relocation record */
if (isrela) {
Elf3264_Rela *rela_p;
/*LINTED pointer cast may result in improper alignment*/
rela_p = (Elf3264_Rela *) ptr;
syminfo = ELF3264_R_SYM(rela_p->r_info);
offset = rela_p->r_offset;
} else {
Elf3264_Rel *rel_p;
/*LINTED pointer cast may result in improper alignment*/
rel_p = (Elf3264_Rel *) ptr;
syminfo = ELF3264_R_SYM(rel_p->r_info);
offset = rel_p->r_offset;
}
/* find the associated symbol table entry */
if (!syminfo)
continue;
sym = sym_table + syminfo;
/* find the associated string table entry */
if (!sym->st_name)
continue;
name = str_table + sym->st_name;
addr = offset + baseaddr;
prexstat = search_info_p->record_func(name, addr, ptr,
search_info_p);
if (prexstat)
break;
}
return (TNFCTL_ERR_NONE);
} /* end _tnfctl_traverse_rela */
/*
* _tnfctl_traverse_dynsym() - this function traverses a dynsym section calling
* the supplied function on each symbol.
*/
/*ARGSUSED*/
tnfctl_errcode_t
_tnfctl_traverse_dynsym(Elf * elf,
char *elfstrs,
Elf_Scn * scn,
GElf_Shdr * shdr,
Elf_Data * data,
uintptr_t baseaddr,
tnfctl_elf_search_t * search_info_p)
{
ulong_t nsyms;
int i;
char *strs;
tnfctl_errcode_t prexstat;
Elf3264_Sym *syms;
/* bail if this isn't a dynsym section */
if (shdr->sh_type != SHT_DYNSYM)
return (TNFCTL_ERR_NONE);
#if 0
printf("### entering _tnfctl_traverse_dynsym...\n");
#endif
syms = data->d_buf;
nsyms = shdr->sh_size / shdr->sh_entsize;
strs = elf_strptr(elf, shdr->sh_link, 0);
DBG_TNF_PROBE_1(_tnfctl_traverse_dynsym_1, "libtnfctl",
"sunw%verbosity 3",
tnf_long, symbols_found, nsyms);
for (i = 0; i < nsyms; i++) {
Elf3264_Sym *sym = &syms[i];
char *name;
uintptr_t addr;
name = strs + sym->st_name;
addr = baseaddr + sym->st_value;
#if 0
if (name != 0)
printf("_tnfctl_traverse_dynsym: name = %s\n", name);
else
printf("_tnfctl_traverse_dynsym: name is 0\n");
#endif
prexstat = search_info_p->record_func(name,
addr, sym, search_info_p);
if (prexstat)
break;
}
#if 0
printf("### leaving _tnfctl_traverse_dynsym...\n");
#endif
return (prexstat);
} /* end _tnfctl_traverse_dynsym */