/* $NetBSD: elf32.c,v 1.10 2013/10/19 17:10:17 christos Exp $ */
/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1996 Christopher G. Demetriou
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the
* NetBSD Project. See
http://www.NetBSD.org/ for
* information about NetBSD.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
*/
#include <sys/cdefs.h>
#if !defined(lint)
__RCSID("$NetBSD: elf32.c,v 1.10 2013/10/19 17:10:17 christos Exp $");
#endif
#ifndef ELFSIZE
#define ELFSIZE 32
#endif
#include <sys/param.h>
#include <sys/exec_elf.h>
#include <sys/queue.h>
#include <dev/lockstat.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
#include "extern.h"
#if (ELFSIZE == 32)
#define NAME(x) x##32
#elif (ELFSIZE == 64)
#define NAME(x) x##64
#endif
static int nsyms;
static Elf_Sym *symp;
static char *strp;
int
NAME(loadsym)(int fd)
{
Elf_Shdr symhdr, strhdr;
Elf_Ehdr ehdr;
size_t sz;
off_t off;
int i;
/*
* Read the ELF header and make sure it's OK.
*/
if (pread(fd, &ehdr, sizeof(ehdr), 0) != sizeof(ehdr))
return -1;
if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
ehdr.e_ident[EI_CLASS] != ELFCLASS)
return -1;
switch (ehdr.e_machine) {
ELFDEFNNAME(MACHDEP_ID_CASES)
default:
return -1;
}
/*
* Find the symbol table header, and make sure the binary isn't
* stripped.
*/
off = ehdr.e_shoff;
for (i = 0; i < ehdr.e_shnum; i++, off += sizeof(symhdr)) {
sz = pread(fd, &symhdr, sizeof(symhdr), off);
if (sz != sizeof(symhdr))
err(EXIT_FAILURE, "pread (section headers)");
if (symhdr.sh_type == SHT_SYMTAB)
break;
}
if (i == ehdr.e_shnum || symhdr.sh_offset == 0)
err(EXIT_FAILURE, "namelist is stripped");
/*
* Pull in the string table header, and then read in both the symbol
* table and string table proper.
*
* XXX We can't use mmap(), as /dev/ksyms doesn't support mmap yet.
*/
off = ehdr.e_shoff + symhdr.sh_link * sizeof(symhdr);
if (pread(fd, &strhdr, sizeof(strhdr), off) != sizeof(strhdr))
err(EXIT_FAILURE, "pread");
if ((symp = malloc(symhdr.sh_size)) == NULL)
err(EXIT_FAILURE, "malloc (symbol table)");
sz = pread(fd, symp, symhdr.sh_size, symhdr.sh_offset);
if (sz != symhdr.sh_size)
err(EXIT_FAILURE, "pread (symbol table)");
if ((strp = malloc(strhdr.sh_size)) == NULL)
err(EXIT_FAILURE, "malloc (string table)");
sz = pread(fd, strp, strhdr.sh_size, strhdr.sh_offset);
if (sz != strhdr.sh_size)
err(EXIT_FAILURE, "pread (string table)");
nsyms = (int)(symhdr.sh_size / sizeof(Elf_Sym));
return 0;
}
int
NAME(findsym)(findsym_t find, char *name, uintptr_t *start, uintptr_t *end)
{
uintptr_t sa, ea;
int i, off;
Elf_Byte st;
switch (find) {
case LOCK_BYNAME:
case LOCK_BYADDR:
st = STT_OBJECT;
break;
case FUNC_BYNAME:
case FUNC_BYADDR:
st = STT_FUNC;
break;
default:
return -1;
}
#ifdef dump_core
static int lastptr[FIND_MAX];
for (i = lastptr[find];;) {
#else
for (i = 0; i < nsyms; i++) {
#endif
switch (find) {
case LOCK_BYNAME:
case FUNC_BYNAME:
if (ELF_ST_TYPE(symp[i].st_info) != st)
break;
if (strcmp(&strp[symp[i].st_name], name) != 0)
break;
*start = (uintptr_t)symp[i].st_value;
*end = *start + (uintptr_t)symp[i].st_size;
goto found;
case LOCK_BYADDR:
case FUNC_BYADDR:
if (ELF_ST_TYPE(symp[i].st_info) != st)
break;
sa = (uintptr_t)symp[i].st_value;
ea = sa + (uintptr_t)symp[i].st_size - 1;
if (*start < sa || *start > ea)
break;
off = (int)(*start - sa);
*start = sa;
if (end != NULL)
*end = ea;
if (name == NULL)
goto found;
if (off == 0)
strlcpy(name, &strp[symp[i].st_name],
NAME_SIZE);
else
snprintf(name, NAME_SIZE, "%s+%x",
&strp[symp[i].st_name], off);
goto found;
default:
break;
}
#ifdef dump_core
if (++i >= nsyms)
i = 0;
if (i == lastptr[find])
return -1;
#endif
}
return -1;
found:
#ifdef dump_core
lastptr[find] = i;
#endif
return 0;
}
