467 lines
10 KiB
C
467 lines
10 KiB
C
/* $NetBSD: readelf.c,v 1.7 2000/07/26 15:19:35 mycroft Exp $ */
|
|
|
|
#include "file.h"
|
|
|
|
#ifdef BUILTIN_ELF
|
|
#include <sys/types.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
#include <ctype.h>
|
|
#include <stdlib.h>
|
|
#ifdef HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
#include <errno.h>
|
|
|
|
#include "readelf.h"
|
|
|
|
#include <sys/cdefs.h>
|
|
#ifndef lint
|
|
#if 0
|
|
FILE_RCSID("@(#)Id: readelf.c,v 1.12 2000/04/11 02:32:35 christos Exp ")
|
|
#else
|
|
__RCSID("$NetBSD: readelf.c,v 1.7 2000/07/26 15:19:35 mycroft Exp $");
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef ELFCORE
|
|
static void dophn_core __P((int, int, int, off_t, int, size_t));
|
|
#endif
|
|
static void dophn_exec __P((int, int, int, off_t, int, size_t));
|
|
static void doshn __P((int, int, int, off_t, int, size_t));
|
|
|
|
static uint16_t getu16 __P((int, int));
|
|
static uint32_t getu32 __P((int, uint32_t));
|
|
static uint64_t getu64 __P((int, uint64_t));
|
|
|
|
static uint16_t
|
|
getu16(swap, value)
|
|
int swap;
|
|
uint16_t value;
|
|
{
|
|
union {
|
|
uint16_t ui;
|
|
char c[2];
|
|
} retval, tmpval;
|
|
|
|
if (swap) {
|
|
tmpval.ui = value;
|
|
|
|
retval.c[0] = tmpval.c[1];
|
|
retval.c[1] = tmpval.c[0];
|
|
|
|
return retval.ui;
|
|
} else
|
|
return value;
|
|
}
|
|
|
|
static uint32_t
|
|
getu32(swap, value)
|
|
int swap;
|
|
uint32_t value;
|
|
{
|
|
union {
|
|
uint32_t ui;
|
|
char c[4];
|
|
} retval, tmpval;
|
|
|
|
if (swap) {
|
|
tmpval.ui = value;
|
|
|
|
retval.c[0] = tmpval.c[3];
|
|
retval.c[1] = tmpval.c[2];
|
|
retval.c[2] = tmpval.c[1];
|
|
retval.c[3] = tmpval.c[0];
|
|
|
|
return retval.ui;
|
|
} else
|
|
return value;
|
|
}
|
|
|
|
static uint64_t
|
|
getu64(swap, value)
|
|
int swap;
|
|
uint64_t value;
|
|
{
|
|
union {
|
|
uint64_t ui;
|
|
char c[8];
|
|
} retval, tmpval;
|
|
|
|
if (swap) {
|
|
tmpval.ui = value;
|
|
|
|
retval.c[0] = tmpval.c[7];
|
|
retval.c[1] = tmpval.c[6];
|
|
retval.c[2] = tmpval.c[5];
|
|
retval.c[3] = tmpval.c[4];
|
|
retval.c[4] = tmpval.c[3];
|
|
retval.c[5] = tmpval.c[2];
|
|
retval.c[6] = tmpval.c[1];
|
|
retval.c[7] = tmpval.c[0];
|
|
|
|
return retval.ui;
|
|
} else
|
|
return value;
|
|
}
|
|
|
|
#define sh_addr (class == ELFCLASS32 \
|
|
? (void *) &sh32 \
|
|
: (void *) &sh64)
|
|
#define shs_type (class == ELFCLASS32 \
|
|
? getu32(swap, sh32.sh_type) \
|
|
: getu32(swap, sh64.sh_type))
|
|
#define ph_addr (class == ELFCLASS32 \
|
|
? (void *) &ph32 \
|
|
: (void *) &ph64)
|
|
#define ph_type (class == ELFCLASS32 \
|
|
? getu32(swap, ph32.p_type) \
|
|
: getu32(swap, ph64.p_type))
|
|
#define ph_offset (class == ELFCLASS32 \
|
|
? getu32(swap, ph32.p_offset) \
|
|
: getu64(swap, ph64.p_offset))
|
|
#define nh_size (class == ELFCLASS32 \
|
|
? sizeof *nh32 \
|
|
: sizeof *nh64)
|
|
#define nh_type (class == ELFCLASS32 \
|
|
? getu32(swap, nh32->n_type) \
|
|
: getu32(swap, nh64->n_type))
|
|
#define nh_namesz (class == ELFCLASS32 \
|
|
? getu32(swap, nh32->n_namesz) \
|
|
: getu32(swap, nh64->n_namesz))
|
|
#define nh_descsz (class == ELFCLASS32 \
|
|
? getu32(swap, nh32->n_descsz) \
|
|
: getu32(swap, nh64->n_descsz))
|
|
#define prpsoffsets(i) (class == ELFCLASS32 \
|
|
? prpsoffsets32[i] \
|
|
: prpsoffsets64[i])
|
|
|
|
static void
|
|
doshn(class, swap, fd, off, num, size)
|
|
int class;
|
|
int swap;
|
|
int fd;
|
|
off_t off;
|
|
int num;
|
|
size_t size;
|
|
{
|
|
Elf32_Shdr sh32;
|
|
Elf64_Shdr sh64;
|
|
|
|
if (lseek(fd, off, SEEK_SET) == -1)
|
|
error("lseek failed (%s).\n", strerror(errno));
|
|
|
|
for ( ; num; num--) {
|
|
if (read(fd, sh_addr, size) == -1)
|
|
error("read failed (%s).\n", strerror(errno));
|
|
if (shs_type == SHT_SYMTAB /* || shs_type == SHT_DYNSYM */) {
|
|
(void) printf (", not stripped");
|
|
return;
|
|
}
|
|
}
|
|
(void) printf (", stripped");
|
|
}
|
|
|
|
/*
|
|
* Look through the program headers of an executable image, searching
|
|
* for a PT_INTERP section; if one is found, it's dynamically linked,
|
|
* otherwise it's statically linked.
|
|
*/
|
|
static void
|
|
dophn_exec(class, swap, fd, off, num, size)
|
|
int class;
|
|
int swap;
|
|
int fd;
|
|
off_t off;
|
|
int num;
|
|
size_t size;
|
|
{
|
|
Elf32_Phdr ph32;
|
|
Elf64_Phdr ph64;
|
|
char *linking_style = "statically";
|
|
char *shared_libraries = "";
|
|
|
|
if (lseek(fd, off, SEEK_SET) == -1)
|
|
error("lseek failed (%s).\n", strerror(errno));
|
|
|
|
for ( ; num; num--) {
|
|
if (read(fd, ph_addr, size) == -1)
|
|
error("read failed (%s).\n", strerror(errno));
|
|
|
|
switch (ph_type) {
|
|
case PT_DYNAMIC:
|
|
linking_style = "dynamically";
|
|
break;
|
|
case PT_INTERP:
|
|
shared_libraries = " (uses shared libs)";
|
|
break;
|
|
}
|
|
}
|
|
printf(", %s linked%s", linking_style, shared_libraries);
|
|
}
|
|
|
|
#ifdef ELFCORE
|
|
size_t prpsoffsets32[] = {
|
|
84, /* SunOS 5.x */
|
|
32, /* Linux */
|
|
};
|
|
|
|
size_t prpsoffsets64[] = {
|
|
120, /* SunOS 5.x, 64-bit */
|
|
};
|
|
|
|
#define NOFFSETS32 (sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
|
|
#define NOFFSETS64 (sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
|
|
|
|
#define NOFFSETS (class == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
|
|
|
|
/*
|
|
* Look through the program headers of an executable image, searching
|
|
* for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE"; if one
|
|
* is found, try looking in various places in its contents for a 16-character
|
|
* string containing only printable characters - if found, that string
|
|
* should be the name of the program that dropped core.
|
|
* Note: right after that 16-character string is, at least in SunOS 5.x
|
|
* (and possibly other SVR4-flavored systems) and Linux, a longer string
|
|
* (80 characters, in 5.x, probably other SVR4-flavored systems, and Linux)
|
|
* containing the start of the command line for that program.
|
|
*/
|
|
static void
|
|
dophn_core(class, swap, fd, off, num, size)
|
|
int class;
|
|
int swap;
|
|
int fd;
|
|
off_t off;
|
|
int num;
|
|
size_t size;
|
|
{
|
|
Elf32_Phdr ph32;
|
|
Elf32_Nhdr *nh32;
|
|
Elf64_Phdr ph64;
|
|
Elf64_Nhdr *nh64;
|
|
size_t offset, noffset, reloffset;
|
|
unsigned char c;
|
|
int i, j;
|
|
char nbuf[BUFSIZ];
|
|
int bufsize;
|
|
|
|
for ( ; num; num--) {
|
|
if (lseek(fd, off, SEEK_SET) == -1)
|
|
error("lseek failed (%s).\n", strerror(errno));
|
|
if (read(fd, ph_addr, size) == -1)
|
|
error("read failed (%s).\n", strerror(errno));
|
|
off += size;
|
|
if (ph_type != PT_NOTE)
|
|
continue;
|
|
if (lseek(fd, (off_t) ph_offset, SEEK_SET) == -1)
|
|
error("lseek failed (%s).\n", strerror(errno));
|
|
bufsize = read(fd, nbuf, BUFSIZ);
|
|
if (bufsize == -1)
|
|
error(": " "read failed (%s).\n", strerror(errno));
|
|
offset = 0;
|
|
for (;;) {
|
|
if (offset >= bufsize)
|
|
break;
|
|
if (class == ELFCLASS32)
|
|
nh32 = (Elf32_Nhdr *)&nbuf[offset];
|
|
else
|
|
nh64 = (Elf64_Nhdr *)&nbuf[offset];
|
|
offset += nh_size;
|
|
|
|
/*
|
|
* If this note isn't an NT_PRPSINFO note, it's
|
|
* not what we're looking for.
|
|
*/
|
|
if (nh_type != NT_PRPSINFO) {
|
|
offset += nh_namesz;
|
|
offset = ((offset + 3)/4)*4;
|
|
offset += nh_descsz;
|
|
offset = ((offset + 3)/4)*4;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Make sure this note has the name "CORE".
|
|
*/
|
|
if (offset + nh_namesz >= bufsize) {
|
|
/*
|
|
* We're past the end of the buffer.
|
|
*/
|
|
break;
|
|
}
|
|
if (nh_namesz != 5
|
|
|| strcmp(&nbuf[offset], "CORE") != 0)
|
|
continue;
|
|
offset += nh_namesz;
|
|
offset = ((offset + 3)/4)*4;
|
|
|
|
/*
|
|
* Extract the program name. We assume it to be
|
|
* 16 characters (that's what it is in SunOS 5.x
|
|
* and Linux).
|
|
*
|
|
* Unfortunately, it's at a different offset in
|
|
* SunOS 5.x and Linux, so try multiple offsets.
|
|
* If the characters aren't all printable, reject
|
|
* it.
|
|
*/
|
|
for (i = 0; i < NOFFSETS; i++) {
|
|
reloffset = prpsoffsets(i);
|
|
noffset = offset + reloffset;
|
|
for (j = 0; j < 16;
|
|
j++, noffset++, reloffset++) {
|
|
/*
|
|
* Make sure we're not past the end
|
|
* of the buffer; if we are, just
|
|
* give up.
|
|
*/
|
|
if (noffset >= bufsize)
|
|
return;
|
|
|
|
/*
|
|
* Make sure we're not past the
|
|
* end of the contents; if we
|
|
* are, this obviously isn't
|
|
* the right offset.
|
|
*/
|
|
if (reloffset >= nh_descsz)
|
|
goto tryanother;
|
|
|
|
c = nbuf[noffset];
|
|
if (c != '\0' && !isprint(c))
|
|
goto tryanother;
|
|
}
|
|
|
|
/*
|
|
* Well, that worked.
|
|
*/
|
|
printf(", from '%.16s'",
|
|
&nbuf[offset + prpsoffsets(i)]);
|
|
return;
|
|
|
|
tryanother:
|
|
;
|
|
}
|
|
offset += nh_descsz;
|
|
offset = ((offset + 3)/4)*4;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
void
|
|
tryelf(fd, buf, nbytes)
|
|
int fd;
|
|
unsigned char *buf;
|
|
int nbytes;
|
|
{
|
|
union {
|
|
int32 l;
|
|
char c[sizeof (int32)];
|
|
} u;
|
|
int class;
|
|
int swap;
|
|
|
|
/*
|
|
* ELF executables have multiple section headers in arbitrary
|
|
* file locations and thus file(1) cannot determine it from easily.
|
|
* Instead we traverse thru all section headers until a symbol table
|
|
* one is found or else the binary is stripped.
|
|
*/
|
|
if (buf[EI_MAG0] != ELFMAG0
|
|
|| (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
|
|
|| buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
|
|
return;
|
|
|
|
|
|
class = buf[4];
|
|
|
|
if (class == ELFCLASS32) {
|
|
Elf32_Ehdr elfhdr;
|
|
if (nbytes <= sizeof (Elf32_Ehdr))
|
|
return;
|
|
|
|
|
|
u.l = 1;
|
|
(void) memcpy(&elfhdr, buf, sizeof elfhdr);
|
|
swap = (u.c[sizeof(int32) - 1] + 1) != elfhdr.e_ident[5];
|
|
|
|
if (getu16(swap, elfhdr.e_type) == ET_CORE)
|
|
#ifdef ELFCORE
|
|
dophn_core(class, swap,
|
|
fd,
|
|
getu32(swap, elfhdr.e_phoff),
|
|
getu16(swap, elfhdr.e_phnum),
|
|
getu16(swap, elfhdr.e_phentsize));
|
|
#else
|
|
;
|
|
#endif
|
|
else {
|
|
if (getu16(swap, elfhdr.e_type) == ET_EXEC) {
|
|
dophn_exec(class, swap,
|
|
fd,
|
|
getu32(swap, elfhdr.e_phoff),
|
|
getu16(swap, elfhdr.e_phnum),
|
|
getu16(swap, elfhdr.e_phentsize));
|
|
}
|
|
doshn(class, swap,
|
|
fd,
|
|
getu32(swap, elfhdr.e_shoff),
|
|
getu16(swap, elfhdr.e_shnum),
|
|
getu16(swap, elfhdr.e_shentsize));
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (class == ELFCLASS64) {
|
|
Elf64_Ehdr elfhdr;
|
|
if (nbytes <= sizeof (Elf64_Ehdr))
|
|
return;
|
|
|
|
|
|
u.l = 1;
|
|
(void) memcpy(&elfhdr, buf, sizeof elfhdr);
|
|
swap = (u.c[sizeof(int32) - 1] + 1) != elfhdr.e_ident[5];
|
|
|
|
if (getu16(swap, elfhdr.e_type) == ET_CORE)
|
|
#ifdef ELFCORE
|
|
dophn_core(class, swap,
|
|
fd,
|
|
#ifdef USE_ARRAY_FOR_64BIT_TYPES
|
|
getu32(swap, elfhdr.e_phoff[1]),
|
|
#else
|
|
getu64(swap, elfhdr.e_phoff),
|
|
#endif
|
|
getu16(swap, elfhdr.e_phnum),
|
|
getu16(swap, elfhdr.e_phentsize));
|
|
#else
|
|
;
|
|
#endif
|
|
else
|
|
{
|
|
if (getu16(swap, elfhdr.e_type) == ET_EXEC) {
|
|
dophn_exec(class, swap,
|
|
fd,
|
|
#ifdef USE_ARRAY_FOR_64BIT_TYPES
|
|
getu32(swap, elfhdr.e_phoff[1]),
|
|
#else
|
|
getu64(swap, elfhdr.e_phoff),
|
|
#endif
|
|
getu16(swap, elfhdr.e_phnum),
|
|
getu16(swap, elfhdr.e_phentsize));
|
|
}
|
|
doshn(class, swap,
|
|
fd,
|
|
#ifdef USE_ARRAY_FOR_64BIT_TYPES
|
|
getu32(swap, elfhdr.e_shoff[1]),
|
|
#else
|
|
getu64(swap, elfhdr.e_shoff),
|
|
#endif
|
|
getu16(swap, elfhdr.e_shnum),
|
|
getu16(swap, elfhdr.e_shentsize));
|
|
}
|
|
return;
|
|
}
|
|
}
|
|
#endif
|