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/*
* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. Please obtain a copy of the License at
* file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. 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 by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
/*
* This file was copied from libc/gen/nlist.c from Darwin's source code
* The version of nlist used as a base is from 10.5.2, libc-498
*
* The full tarball is at:
*
* I've modified it to be compatible with 64-bit images.
*/
#include "breakpad_nlist_64.h"
#include <CoreFoundation/CoreFoundation.h>
#include <fcntl.h>
#include <mach-o/nlist.h>
#include <mach-o/loader.h>
#include <mach-o/fat.h>
#include <mach/mach.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <TargetConditionals.h>
#include <unistd.h>
/* Stuff lifted from <a.out.h> and <sys/exec.h> since they are gone */
/*
* Header prepended to each a.out file.
*/
struct exec {
unsigned short a_machtype; /* machine type */
unsigned short a_magic; /* magic number */
unsigned long a_text; /* size of text segment */
unsigned long a_data; /* size of initialized data */
unsigned long a_bss; /* size of uninitialized data */
unsigned long a_syms; /* size of symbol table */
unsigned long a_entry; /* entry point */
unsigned long a_trsize; /* size of text relocation */
unsigned long a_drsize; /* size of data relocation */
};
#define OMAGIC 0407 /* old impure format */
#define NMAGIC 0410 /* read-only text */
#define ZMAGIC 0413 /* demand load format */
#define N_BADMAG(x) \
(((x).a_magic)!=OMAGIC && ((x).a_magic)!=NMAGIC && ((x).a_magic)!=ZMAGIC)
#define N_TXTOFF(x) \
((x).a_magic==ZMAGIC ? 0 : sizeof (struct exec))
#define N_SYMOFF(x) \
(N_TXTOFF(x) + (x).a_text+(x).a_data + (x).a_trsize+(x).a_drsize)
// Traits structs for specializing function templates to handle
// 32-bit/64-bit Mach-O files.
template<typename T>
struct MachBits {};
typedef struct nlist nlist32;
typedef struct nlist_64 nlist64;
template<>
struct MachBits<nlist32> {
typedef mach_header mach_header_type;
typedef uint32_t word_type;
static const uint32_t magic = MH_MAGIC;
};
template<>
struct MachBits<nlist64> {
typedef mach_header_64 mach_header_type;
typedef uint64_t word_type;
static const uint32_t magic = MH_MAGIC_64;
};
template<typename nlist_type>
int
__breakpad_fdnlist(int fd, nlist_type *list, const char **symbolNames,
cpu_type_t cpu_type);
/*
* nlist - retreive attributes from name list (string table version)
*/
template <typename nlist_type>
int breakpad_nlist_common(const char *name,
nlist_type *list,
const char **symbolNames,
cpu_type_t cpu_type) {
int fd = open(name, O_RDONLY, 0);
if (fd < 0)
return -1;
int n = __breakpad_fdnlist(fd, list, symbolNames, cpu_type);
close(fd);
return n;
}
int breakpad_nlist(const char *name,
struct nlist *list,
const char **symbolNames,
cpu_type_t cpu_type) {
return breakpad_nlist_common(name, list, symbolNames, cpu_type);
}
int breakpad_nlist(const char *name,
struct nlist_64 *list,
const char **symbolNames,
cpu_type_t cpu_type) {
return breakpad_nlist_common(name, list, symbolNames, cpu_type);
}
/* Note: __fdnlist() is called from kvm_nlist in libkvm's kvm.c */
template<typename nlist_type>
int __breakpad_fdnlist(int fd, nlist_type *list, const char **symbolNames,
cpu_type_t cpu_type) {
typedef typename MachBits<nlist_type>::mach_header_type mach_header_type;
typedef typename MachBits<nlist_type>::word_type word_type;
const uint32_t magic = MachBits<nlist_type>::magic;
int maxlen = 500;
int nreq = 0;
for (nlist_type* q = list;
symbolNames[q-list] && symbolNames[q-list][0];
q++, nreq++) {
q->n_type = 0;
q->n_value = 0;
q->n_desc = 0;
q->n_sect = 0;
q->n_un.n_strx = 0;
}
struct exec buf;
if (read(fd, (char *)&buf, sizeof(buf)) != sizeof(buf) ||
(N_BADMAG(buf) && *((uint32_t *)&buf) != magic &&
CFSwapInt32BigToHost(*((uint32_t *)&buf)) != FAT_MAGIC &&
/* The following is the big-endian ppc64 check */
(*((uint32_t*)&buf)) != FAT_MAGIC)) {
return -1;
}
/* Deal with fat file if necessary */
unsigned arch_offset = 0;
if (CFSwapInt32BigToHost(*((uint32_t *)&buf)) == FAT_MAGIC ||
/* The following is the big-endian ppc64 check */
*((unsigned int *)&buf) == FAT_MAGIC) {
/* Read in the fat header */
struct fat_header fh;
if (lseek(fd, 0, SEEK_SET) == -1) {
return -1;
}
if (read(fd, (char *)&fh, sizeof(fh)) != sizeof(fh)) {
return -1;
}
/* Convert fat_narchs to host byte order */
fh.nfat_arch = CFSwapInt32BigToHost(fh.nfat_arch);
/* Read in the fat archs */
struct fat_arch *fat_archs =
(struct fat_arch *)malloc(fh.nfat_arch * sizeof(struct fat_arch));
if (fat_archs == NULL) {
return -1;
}
if (read(fd, (char *)fat_archs,
sizeof(struct fat_arch) * fh.nfat_arch) !=
(ssize_t)(sizeof(struct fat_arch) * fh.nfat_arch)) {
free(fat_archs);
return -1;
}
/*
* Convert archs to host byte ordering (a constraint of
* cpusubtype_getbestarch()
*/
for (unsigned i = 0; i < fh.nfat_arch; i++) {
fat_archs[i].cputype =
CFSwapInt32BigToHost(fat_archs[i].cputype);
fat_archs[i].cpusubtype =
CFSwapInt32BigToHost(fat_archs[i].cpusubtype);
fat_archs[i].offset =
CFSwapInt32BigToHost(fat_archs[i].offset);
fat_archs[i].size =
CFSwapInt32BigToHost(fat_archs[i].size);
fat_archs[i].align =
CFSwapInt32BigToHost(fat_archs[i].align);
}
struct fat_arch *fap = NULL;
for (unsigned i = 0; i < fh.nfat_arch; i++) {
if (fat_archs[i].cputype == cpu_type) {
fap = &fat_archs[i];
break;
}
}
if (!fap) {
free(fat_archs);
return -1;
}
arch_offset = fap->offset;
free(fat_archs);
/* Read in the beginning of the architecture-specific file */
if (lseek(fd, arch_offset, SEEK_SET) == -1) {
return -1;
}
if (read(fd, (char *)&buf, sizeof(buf)) != sizeof(buf)) {
return -1;
}
}
off_t sa; /* symbol address */
off_t ss; /* start of strings */
register_t n;
if (*((unsigned int *)&buf) == magic) {
if (lseek(fd, arch_offset, SEEK_SET) == -1) {
return -1;
}
mach_header_type mh;
if (read(fd, (char *)&mh, sizeof(mh)) != sizeof(mh)) {
return -1;
}
struct load_command *load_commands =
(struct load_command *)malloc(mh.sizeofcmds);
if (load_commands == NULL) {
return -1;
}
if (read(fd, (char *)load_commands, mh.sizeofcmds) !=
(ssize_t)mh.sizeofcmds) {
free(load_commands);
return -1;
}
struct symtab_command *stp = NULL;
struct load_command *lcp = load_commands;
// iterate through all load commands, looking for
// LC_SYMTAB load command
for (uint32_t i = 0; i < mh.ncmds; i++) {
if (lcp->cmdsize % sizeof(word_type) != 0 ||
lcp->cmdsize <= 0 ||
(char *)lcp + lcp->cmdsize >
(char *)load_commands + mh.sizeofcmds) {
free(load_commands);
return -1;
}
if (lcp->cmd == LC_SYMTAB) {
if (lcp->cmdsize !=
sizeof(struct symtab_command)) {
free(load_commands);
return -1;
}
stp = (struct symtab_command *)lcp;
break;
}
lcp = (struct load_command *)
((char *)lcp + lcp->cmdsize);
}
if (stp == NULL) {
free(load_commands);
return -1;
}
// sa points to the beginning of the symbol table
sa = stp->symoff + arch_offset;
// ss points to the beginning of the string table
ss = stp->stroff + arch_offset;
// n is the number of bytes in the symbol table
// each symbol table entry is an nlist structure
n = stp->nsyms * sizeof(nlist_type);
free(load_commands);
} else {
sa = N_SYMOFF(buf) + arch_offset;
ss = sa + buf.a_syms + arch_offset;
n = buf.a_syms;
}
if (lseek(fd, sa, SEEK_SET) == -1) {
return -1;
}
// the algorithm here is to read the nlist entries in m-sized
// chunks into q. q is then iterated over. for each entry in q,
// use the string table index(q->n_un.n_strx) to read the symbol
// name, then scan the nlist entries passed in by the user(via p),
// and look for a match
while (n) {
nlist_type space[BUFSIZ/sizeof (nlist_type)];
register_t m = sizeof (space);
if (n < m)
m = n;
if (read(fd, (char *)space, m) != m)
break;
n -= m;
off_t savpos = lseek(fd, 0, SEEK_CUR);
if (savpos == -1) {
return -1;
}
for (nlist_type* q = space; (m -= sizeof(nlist_type)) >= 0; q++) {
char nambuf[BUFSIZ];
if (q->n_un.n_strx == 0 || q->n_type & N_STAB)
continue;
// seek to the location in the binary where the symbol
// name is stored & read it into memory
if (lseek(fd, ss+q->n_un.n_strx, SEEK_SET) == -1) {
return -1;
}
if (read(fd, nambuf, maxlen+1) == -1) {
return -1;
}
const char *s2 = nambuf;
for (nlist_type *p = list;
symbolNames[p-list] && symbolNames[p-list][0];
p++) {
// get the symbol name the user has passed in that
// corresponds to the nlist entry that we're looking at
const char *s1 = symbolNames[p - list];
while (*s1) {
if (*s1++ != *s2++)
goto cont;
}
if (*s2)
goto cont;
p->n_value = q->n_value;
p->n_type = q->n_type;
p->n_desc = q->n_desc;
p->n_sect = q->n_sect;
p->n_un.n_strx = q->n_un.n_strx;
if (--nreq == 0)
return nreq;
break;
cont: ;
}
}
if (lseek(fd, savpos, SEEK_SET) == -1) {
return -1;
}
}
return nreq;
}