#include "file.h"
#ifdef BUILTIN_ELF
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "readelf.h"
#ifndef lint
FILE_RCSID("@(#)$Id: readelf.c,v 1.1 2003/07/02 18:01:22 eseidel Exp $")
#endif
#ifdef ELFCORE
private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t);
#endif
private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t);
private int doshn(struct magic_set *, int, int, int, off_t, int, size_t);
private size_t donote(struct magic_set *, unsigned char *, size_t, size_t, int,
int, int);
#define ELF_ALIGN(a) ((((a) + align - 1) / align) * align)
private uint16_t getu16(int, uint16_t);
private uint32_t getu32(int, uint32_t);
private uint64_t getu64(int, uint64_t);
private uint16_t
getu16(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;
}
private uint32_t
getu32(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;
}
private uint64_t
getu64(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 sh_size (class == ELFCLASS32 \
? sizeof sh32 \
: sizeof 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_size (class == ELFCLASS32 \
? sizeof ph32 \
: sizeof 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 ph_align (int)((class == ELFCLASS32 \
? (off_t) (ph32.p_align ? \
getu32(swap, ph32.p_align) : 4) \
: (off_t) (ph64.p_align ? \
getu64(swap, ph64.p_align) : 4)))
#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])
#ifdef ELFCORE
size_t prpsoffsets32[] = {
8,
28,
32,
84,
};
size_t prpsoffsets64[] = {
120,
};
#define NOFFSETS32 (sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
#define NOFFSETS64 (sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
#define NOFFSETS (class == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
#define OS_STYLE_SVR4 0
#define OS_STYLE_FREEBSD 1
#define OS_STYLE_NETBSD 2
private const char *os_style_names[] = {
"SVR4",
"FreeBSD",
"NetBSD",
};
private int
dophn_core(struct magic_set *ms, int class, int swap, int fd, off_t off,
int num, size_t size)
{
Elf32_Phdr ph32;
Elf64_Phdr ph64;
size_t offset;
unsigned char nbuf[BUFSIZ];
int bufsize;
if (size != ph_size) {
file_error(ms, "Corrupted program header size");
return -1;
}
for ( ; num; num--) {
if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
file_badseek(ms);
return -1;
}
if (read(fd, ph_addr, ph_size) == -1) {
file_badread(ms);
return -1;
}
off += size;
if (ph_type != PT_NOTE)
continue;
if (lseek(fd, (off_t) ph_offset, SEEK_SET) == (off_t)-1) {
file_badseek(ms);
return -1;
}
bufsize = read(fd, nbuf, BUFSIZ);
if (bufsize == -1) {
file_badread(ms);
return -1;
}
offset = 0;
for (;;) {
if (offset >= bufsize)
break;
offset = donote(ms, nbuf, offset, (size_t)bufsize,
class, swap, 4);
}
}
return 0;
}
#endif
private size_t
donote(struct magic_set *ms, unsigned char *nbuf, size_t offset, size_t size,
int class, int swap, int align)
{
Elf32_Nhdr nh32;
Elf64_Nhdr nh64;
size_t noff, doff;
#ifdef ELFCORE
int os_style = -1;
#endif
if (class == ELFCLASS32)
memcpy(&nh32, &nbuf[offset], sizeof(nh32));
else
memcpy(&nh64, &nbuf[offset], sizeof(nh64));
offset += nh_size;
if ((nh_namesz == 0) && (nh_descsz == 0)) {
return offset;
}
noff = offset;
doff = ELF_ALIGN(offset + nh_namesz);
if (offset + nh_namesz >= size) {
return doff;
}
offset = ELF_ALIGN(doff + nh_descsz);
if (offset + nh_descsz >= size)
return offset;
if (nh_namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
nh_type == NT_GNU_VERSION && nh_descsz == 16) {
uint32_t desc[4];
(void)memcpy(desc, &nbuf[doff], sizeof(desc));
if (file_printf(ms, ", for GNU/") == -1)
return size;
switch (getu32(swap, desc[0])) {
case GNU_OS_LINUX:
if (file_printf(ms, "Linux") == -1)
return size;
break;
case GNU_OS_HURD:
if (file_printf(ms, "Hurd") == -1)
return size;
break;
case GNU_OS_SOLARIS:
if (file_printf(ms, "Solaris") == -1)
return size;
break;
default:
if (file_printf(ms, "<unknown>") == -1)
return size;
}
if (file_printf(ms, " %d.%d.%d", getu32(swap, desc[1]),
getu32(swap, desc[2]), getu32(swap, desc[3])) == -1)
return size;
return size;
}
if (nh_namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0 &&
nh_type == NT_NETBSD_VERSION && nh_descsz == 4) {
uint32_t desc;
(void)memcpy(&desc, &nbuf[doff], sizeof(desc));
desc = getu32(swap, desc);
if (file_printf(ms, ", for NetBSD") == -1)
return size;
if (desc > 100000000U) {
u_int ver_patch = (desc / 100) % 100;
u_int ver_rel = (desc / 10000) % 100;
u_int ver_min = (desc / 1000000) % 100;
u_int ver_maj = desc / 100000000;
if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
return size;
if (ver_rel == 0 && ver_patch != 0) {
if (file_printf(ms, ".%u", ver_patch) == -1)
return size;
} else if (ver_rel != 0 && ver_rel <= 26) {
if (file_printf(ms, "%c", 'A' + ver_rel - 1)
== -1)
return size;
} else if (ver_rel != 0 && ver_rel <= 52) {
if (file_printf(ms, "Z%c", 'A' + ver_rel - 1)
== -1)
return size;
} else if (ver_rel != 0) {
if (file_printf(ms, "<unknown>") == -1)
return size;
}
}
return size;
}
if (nh_namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0 &&
nh_type == NT_FREEBSD_VERSION && nh_descsz == 4) {
uint32_t desc;
(void)memcpy(&desc, &nbuf[doff], sizeof(desc));
desc = getu32(swap, desc);
if (file_printf(ms, ", for FreeBSD") == -1)
return size;
if (file_printf(ms, " %d.%d", desc / 100000, desc / 10000 % 10)
== -1)
return size;
if (desc / 1000 % 10 > 0)
if (file_printf(ms, ".%d", desc / 1000 % 10) == -1)
return size;
return size;
}
if (nh_namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
nh_type == NT_OPENBSD_VERSION && nh_descsz == 4) {
if (file_printf(ms, ", for OpenBSD") == -1)
return size;
return size;
}
if ((nh_namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
(nh_namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
os_style = OS_STYLE_SVR4;
}
if ((nh_namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
os_style = OS_STYLE_FREEBSD;
}
if ((nh_namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
== 0)) {
os_style = OS_STYLE_NETBSD;
}
#ifdef ELFCORE
if (os_style != -1)
if (file_printf(ms, ", %s-style", os_style_names[os_style]) == -1)
return size;
if (os_style == OS_STYLE_NETBSD && nh_type == NT_NETBSD_CORE_PROCINFO) {
uint32_t signo;
if (file_printf(ms, ", from '%.31s'", &nbuf[doff + 0x7c]) == -1)
return size;
memcpy(&signo, &nbuf[doff + 0x08],
sizeof(signo));
if (file_printf(ms, " (signal %u)", getu32(swap, signo)) == -1)
return size;
return size;
} else if (os_style != OS_STYLE_NETBSD && nh_type == NT_PRPSINFO) {
int i, j;
unsigned char c;
for (i = 0; i < NOFFSETS; i++) {
size_t reloffset = prpsoffsets(i);
size_t noffset = doff + reloffset;
for (j = 0; j < 16; j++, noffset++, reloffset++) {
if (noffset >= size)
goto tryanother;
if (reloffset >= nh_descsz)
goto tryanother;
c = nbuf[noffset];
if (c == '\0') {
if (j == 0)
goto tryanother;
else
break;
} else {
#define isquote(c) (strchr("'\"`", (c)) != NULL)
if (!isprint(c) || isquote(c))
goto tryanother;
}
}
if (file_printf(ms, ", from '%.16s'",
&nbuf[doff + prpsoffsets(i)]) == -1)
return size;
return size;
tryanother:
;
}
return offset;
}
#endif
return offset;
}
private int
doshn(struct magic_set *ms, int class, int swap, int fd, off_t off, int num,
size_t size)
{
Elf32_Shdr sh32;
Elf64_Shdr sh64;
if (size != sh_size) {
file_error(ms, "Corrupted section header size");
return -1;
}
if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
file_badseek(ms);
return -1;
}
for ( ; num; num--) {
if (read(fd, sh_addr, sh_size) == -1) {
file_badread(ms);
return -1;
}
if (shs_type == SHT_SYMTAB ) {
if (file_printf(ms, ", not stripped") == -1)
return -1;
return 0;
}
}
if (file_printf(ms, ", stripped") == -1)
return -1;
return 0;
}
private int
dophn_exec(struct magic_set *ms, int class, int swap, int fd, off_t off,
int num, size_t size)
{
Elf32_Phdr ph32;
Elf64_Phdr ph64;
const char *linking_style = "statically";
const char *shared_libraries = "";
unsigned char nbuf[BUFSIZ];
int bufsize;
size_t offset;
off_t savedoffset;
if (size != ph_size) {
file_error(ms, "Corrupted program header size");
return -1;
}
if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
file_badseek(ms);
return -1;
}
for ( ; num; num--) {
if (read(fd, ph_addr, ph_size) == -1) {
file_badread(ms);
return -1;
}
if ((savedoffset = lseek(fd, (off_t)0, SEEK_CUR)) == (off_t)-1) {
file_badseek(ms);
return -1;
}
switch (ph_type) {
case PT_DYNAMIC:
linking_style = "dynamically";
break;
case PT_INTERP:
shared_libraries = " (uses shared libs)";
break;
case PT_NOTE:
if (lseek(fd, (off_t) ph_offset, SEEK_SET)
== (off_t)-1) {
file_badseek(ms);
return -1;
}
bufsize = read(fd, nbuf, sizeof(nbuf));
if (bufsize == -1) {
file_badread(ms);
return -1;
}
offset = 0;
for (;;) {
if (offset >= bufsize)
break;
offset = donote(ms, nbuf, offset,
(size_t)bufsize, class, swap, ph_align);
}
if (lseek(fd, savedoffset + offset, SEEK_SET)
== (off_t)-1) {
file_badseek(ms);
return -1;
}
break;
}
}
if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
== -1)
return -1;
return 0;
}
protected int
file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
size_t nbytes)
{
union {
int32_t l;
char c[sizeof (int32_t)];
} u;
int class;
int swap;
if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
fd = file_pipe2file(ms, fd, buf, nbytes);
if (buf[EI_MAG0] != ELFMAG0
|| (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
|| buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
return 0;
class = buf[4];
if (class == ELFCLASS32) {
Elf32_Ehdr elfhdr;
if (nbytes <= sizeof (Elf32_Ehdr))
return 0;
u.l = 1;
(void) memcpy(&elfhdr, buf, sizeof elfhdr);
swap = (u.c[sizeof(int32_t) - 1] + 1) != elfhdr.e_ident[5];
if (getu16(swap, elfhdr.e_type) == ET_CORE) {
#ifdef ELFCORE
if (dophn_core(ms, class, swap, fd,
(off_t)getu32(swap, elfhdr.e_phoff),
getu16(swap, elfhdr.e_phnum),
(size_t)getu16(swap, elfhdr.e_phentsize)) == -1)
return -1;
#else
;
#endif
} else {
if (getu16(swap, elfhdr.e_type) == ET_EXEC) {
if (dophn_exec(ms, class, swap,
fd, (off_t)getu32(swap, elfhdr.e_phoff),
getu16(swap, elfhdr.e_phnum),
(size_t)getu16(swap, elfhdr.e_phentsize))
== -1)
return -1;
}
if (doshn(ms, class, swap, fd,
(off_t)getu32(swap, elfhdr.e_shoff),
getu16(swap, elfhdr.e_shnum),
(size_t)getu16(swap, elfhdr.e_shentsize)) == -1)
return -1;
}
return 1;
}
if (class == ELFCLASS64) {
Elf64_Ehdr elfhdr;
if (nbytes <= sizeof (Elf64_Ehdr))
return 0;
u.l = 1;
(void) memcpy(&elfhdr, buf, sizeof elfhdr);
swap = (u.c[sizeof(int32_t) - 1] + 1) != elfhdr.e_ident[5];
if (getu16(swap, elfhdr.e_type) == ET_CORE) {
#ifdef ELFCORE
if (dophn_core(ms, class, swap, fd,
#ifdef USE_ARRAY_FOR_64BIT_TYPES
(off_t)getu32(swap, elfhdr.e_phoff[1]),
#else
(off_t)getu64(swap, elfhdr.e_phoff),
#endif
getu16(swap, elfhdr.e_phnum),
(size_t)getu16(swap, elfhdr.e_phentsize)) == -1)
return -1;
#else
;
#endif
} else {
if (getu16(swap, elfhdr.e_type) == ET_EXEC) {
if (dophn_exec(ms, class, swap, fd,
#ifdef USE_ARRAY_FOR_64BIT_TYPES
(off_t)getu32(swap, elfhdr.e_phoff[1]),
#else
(off_t)getu64(swap, elfhdr.e_phoff),
#endif
getu16(swap, elfhdr.e_phnum),
(size_t)getu16(swap, elfhdr.e_phentsize))
== -1)
return -1;
}
if (doshn(ms, class, swap, fd,
#ifdef USE_ARRAY_FOR_64BIT_TYPES
(off_t)getu32(swap, elfhdr.e_shoff[1]),
#else
(off_t)getu64(swap, elfhdr.e_shoff),
#endif
getu16(swap, elfhdr.e_shnum),
(size_t)getu16(swap, elfhdr.e_shentsize)) == -1)
return -1;
}
return 1;
}
return 0;
}
#endif