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/*
* Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <unistd.h>
#include "orc.h"
#include "warn.h"
static const char *reg_name(unsigned int reg)
{
switch (reg) {
case ORC_REG_PREV_SP:
return "prevsp";
case ORC_REG_DX:
return "dx";
case ORC_REG_DI:
return "di";
case ORC_REG_BP:
return "bp";
case ORC_REG_SP:
return "sp";
case ORC_REG_R10:
return "r10";
case ORC_REG_R13:
return "r13";
case ORC_REG_BP_INDIRECT:
return "bp(ind)";
case ORC_REG_SP_INDIRECT:
return "sp(ind)";
default:
return "?";
}
}
static const char *orc_type_name(unsigned int type)
{
switch (type) {
case ORC_TYPE_CALL:
return "call";
case ORC_TYPE_REGS:
return "regs";
case ORC_TYPE_REGS_IRET:
return "iret";
default:
return "?";
}
}
static void print_reg(unsigned int reg, int offset)
{
if (reg == ORC_REG_BP_INDIRECT)
printf("(bp%+d)", offset);
else if (reg == ORC_REG_SP_INDIRECT)
printf("(sp%+d)", offset);
else if (reg == ORC_REG_UNDEFINED)
printf("(und)");
else
printf("%s%+d", reg_name(reg), offset);
}
int orc_dump(const char *_objname)
{
int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0;
struct orc_entry *orc = NULL;
char *name;
size_t nr_sections;
Elf64_Addr orc_ip_addr = 0;
size_t shstrtab_idx, strtab_idx = 0;
Elf *elf;
Elf_Scn *scn;
GElf_Shdr sh;
GElf_Rela rela;
GElf_Sym sym;
Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
objname = _objname;
elf_version(EV_CURRENT);
fd = open(objname, O_RDONLY);
if (fd == -1) {
perror("open");
return -1;
}
elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
if (!elf) {
WARN_ELF("elf_begin");
return -1;
}
if (elf_getshdrnum(elf, &nr_sections)) {
WARN_ELF("elf_getshdrnum");
return -1;
}
if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
WARN_ELF("elf_getshdrstrndx");
return -1;
}
for (i = 0; i < nr_sections; i++) {
scn = elf_getscn(elf, i);
if (!scn) {
WARN_ELF("elf_getscn");
return -1;
}
if (!gelf_getshdr(scn, &sh)) {
WARN_ELF("gelf_getshdr");
return -1;
}
name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
if (!name) {
WARN_ELF("elf_strptr");
return -1;
}
data = elf_getdata(scn, NULL);
if (!data) {
WARN_ELF("elf_getdata");
return -1;
}
if (!strcmp(name, ".symtab")) {
symtab = data;
} else if (!strcmp(name, ".strtab")) {
strtab_idx = i;
} else if (!strcmp(name, ".orc_unwind")) {
orc = data->d_buf;
orc_size = sh.sh_size;
} else if (!strcmp(name, ".orc_unwind_ip")) {
orc_ip = data->d_buf;
orc_ip_addr = sh.sh_addr;
} else if (!strcmp(name, ".rela.orc_unwind_ip")) {
rela_orc_ip = data;
}
}
if (!symtab || !strtab_idx || !orc || !orc_ip)
return 0;
if (orc_size % sizeof(*orc) != 0) {
WARN("bad .orc_unwind section size");
return -1;
}
nr_entries = orc_size / sizeof(*orc);
for (i = 0; i < nr_entries; i++) {
if (rela_orc_ip) {
if (!gelf_getrela(rela_orc_ip, i, &rela)) {
WARN_ELF("gelf_getrela");
return -1;
}
if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
WARN_ELF("gelf_getsym");
return -1;
}
if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
scn = elf_getscn(elf, sym.st_shndx);
if (!scn) {
WARN_ELF("elf_getscn");
return -1;
}
if (!gelf_getshdr(scn, &sh)) {
WARN_ELF("gelf_getshdr");
return -1;
}
name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
if (!name) {
WARN_ELF("elf_strptr");
return -1;
}
} else {
name = elf_strptr(elf, strtab_idx, sym.st_name);
if (!name) {
WARN_ELF("elf_strptr");
return -1;
}
}
printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
} else {
printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
}
printf(" sp:");
print_reg(orc[i].sp_reg, orc[i].sp_offset);
printf(" bp:");
print_reg(orc[i].bp_reg, orc[i].bp_offset);
printf(" type:%s end:%d\n",
orc_type_name(orc[i].type), orc[i].end);
}
elf_end(elf);
close(fd);
return 0;
}
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