freebsd-dev/usr.sbin/kvm_mkdb/nlist.c
Peter Wemm 046e06a57c Initial support for dealing with an elf /kernel. This is a loose hybrid
of OpenBSD's elf nlist code for this, and our a.out version.  The OpenBSD
version was mainly a seek/read system with a mmap of the string table,
this one simply mmap's the lot (like the a.out version).

Obtained from:  a fair chunk from OpenBSD
1997-08-30 23:35:00 +00:00

338 lines
8.3 KiB
C

/*-
* Copyright (c) 1990, 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "from: @(#)nlist.c 8.1 (Berkeley) 6/6/93";
#else
static char *rcsid = "$Id$";
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <a.out.h>
#include <db.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "extern.h"
#ifdef DO_ELF
#include <elf.h>
#endif
typedef struct nlist NLIST;
#define _strx n_un.n_strx
#define _name n_un.n_name
#define badfmt(str) errx(1, "%s: %s: %s", kfile, str, strerror(EFTYPE))
static char *kfile;
#if defined(DO_AOUT)
int
__aout_knlist(name, db)
char *name;
DB *db;
{
register int nsyms;
struct exec *ebuf;
NLIST *nbuf;
DBT data, key;
int fd;
char *strtab;
u_char *filep;
char *vp;
struct stat sst;
long cur_off, voff;
kfile = name;
if ((fd = open(name, O_RDONLY, 0)) < 0)
err(1, "%s", name);
fstat(fd,&sst);
filep = (u_char*)mmap(0, sst.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (filep == (u_char*)MAP_FAILED)
err(1, "mmap failed");
/* Read in exec structure. */
ebuf = (struct exec *) filep;
/* Check magic number and symbol count. */
if (N_BADMAG(*ebuf))
badfmt("bad magic number");
if (!ebuf->a_syms)
badfmt("stripped");
strtab = filep + N_STROFF(*ebuf) + sizeof (int);
/* Seek to symbol table. */
cur_off = N_SYMOFF(*ebuf);
/* Read each symbol and enter it into the database. */
nsyms = ebuf->a_syms / sizeof(struct nlist);
while (nsyms--) {
nbuf = (NLIST *)(filep + cur_off);
cur_off += sizeof(NLIST);
if (!nbuf->_strx || nbuf->n_type&N_STAB)
continue;
key.data = (u_char *)strtab + nbuf->_strx - sizeof(long);
key.size = strlen((char *)key.data);
data.data = (u_char *)nbuf;
data.size = sizeof(NLIST);
if (db->put(db, &key, &data, 0))
err(1, "record enter");
if (1 && strcmp((char *)key.data, VRS_SYM) == 0) {
#ifndef KERNTEXTOFF
/*
* XXX
* The FreeBSD bootloader loads the kernel at the a_entry address, meaning
* that this is where the kernel starts. (not at KERNBASE)
*
* This may be introducing an i386 dependency.
*/
#if defined(__FreeBSD__)
#define KERNTEXTOFF ebuf->a_entry
#else
#define KERNTEXTOFF KERNBASE
#endif
#endif
/*
* Calculate offset relative to a normal (non-kernel)
* a.out. KERNTEXTOFF is where the kernel is really
* loaded; N_TXTADDR is where a normal file is loaded.
* From there, locate file offset in text or data.
*/
voff = nbuf->n_value - KERNTEXTOFF + N_TXTADDR(*ebuf);
if ((nbuf->n_type & N_TYPE) == N_TEXT)
voff += N_TXTOFF(*ebuf) - N_TXTADDR(*ebuf);
else
voff += N_DATOFF(*ebuf) - N_DATADDR(*ebuf);
vp = filep + voff;
key.data = (u_char *)VRS_KEY;
key.size = sizeof(VRS_KEY) - 1;
data.data = vp;
data.size = strchr(vp, '\n') - vp + 1;
if (db->put(db, &key, &data, 0))
err(1, "record enter");
/* Restore to original values. */
data.size = sizeof(NLIST);
}
}
}
#endif /* DO_AOUT */
#ifdef DO_ELF
int
__elf_knlist(name, db)
char *name;
DB *db;
{
register caddr_t strtab;
register off_t symstroff, symoff;
register u_long symsize;
register u_long kernvma, kernoffs;
register int i;
Elf32_Sym *sbuf;
size_t symstrsize;
char *shstr, buf[1024];
Elf32_Ehdr *eh;
Elf32_Shdr *sh = NULL;
DBT data, key;
NLIST nbuf;
int fd;
u_char *filep;
struct stat sst;
kfile = name;
if ((fd = open(name, O_RDONLY, 0)) < 0)
err(1, "%s", name);
fstat(fd, &sst);
/* Check for files too large to mmap. */
/* XXX is this really possible? */
if (sst.st_size > SIZE_T_MAX) {
badfmt("corrupt file");
}
filep = (u_char*)mmap(0, sst.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (filep == (u_char*)MAP_FAILED)
err(1, "mmap failed");
/* Read in exec structure. */
eh = (Elf32_Ehdr *) filep;
if (!IS_ELF(*eh))
return(-1);
sh = (Elf32_Shdr *)&filep[eh->e_shoff];
shstr = (char *)&filep[sh[eh->e_shstrndx].sh_offset];
for (i = 0; i < eh->e_shnum; i++) {
if (strcmp (shstr + sh[i].sh_name, ".strtab") == 0) {
symstroff = sh[i].sh_offset;
symstrsize = sh[i].sh_size;
}
else if (strcmp (shstr + sh[i].sh_name, ".symtab") == 0) {
symoff = sh[i].sh_offset;
symsize = sh[i].sh_size;
}
else if (strcmp (shstr + sh[i].sh_name, ".text") == 0) {
kernvma = sh[i].sh_addr;
kernoffs = sh[i].sh_offset;
}
}
strtab = (char *)&filep[symstroff];
data.data = (u_char *)&nbuf;
data.size = sizeof(NLIST);
/* Read each symbol and enter it into the database. */
for (i = 0; symsize > 0; i++, symsize -= sizeof(Elf32_Sym)) {
sbuf = (Elf32_Sym *)&filep[symoff + i * sizeof(*sbuf)];
if (!sbuf->st_name)
continue;
nbuf.n_value = sbuf->st_value;
/*XXX type conversion is pretty rude... */
switch (ELF32_ST_TYPE(sbuf->st_info)) {
case STT_NOTYPE:
nbuf.n_type = N_UNDF;
break;
case STT_FUNC:
nbuf.n_type = N_TEXT;
break;
case STT_OBJECT:
nbuf.n_type = N_DATA;
break;
}
if (ELF32_ST_BIND(sbuf->st_info) == STB_LOCAL)
nbuf.n_type = N_EXT;
key.data = (u_char *)(strtab + sbuf->st_name);
key.size = strlen((char *)key.data);
if (db->put(db, &key, &data, 0))
err(1, "record enter");
/* also put in name prefixed with _ */
*buf = '_';
strcpy(buf + 1, strtab + sbuf->st_name);
key.data = (u_char *)buf;
key.size = strlen((char *)key.data);
if (db->put(db, &key, &data, 0))
err(1, "record enter");
/* Special processing for "_version" (depends on above) */
if (strcmp((char *)key.data, VRS_SYM) == 0) {
char *vp;
key.data = (u_char *)VRS_KEY;
key.size = sizeof(VRS_KEY) - 1;
/* Find the version string, relative to its section */
data.data = strdup(&filep[nbuf.n_value -
sh[sbuf->st_shndx].sh_addr +
sh[sbuf->st_shndx].sh_offset]);
/* assumes newline terminates version. */
if ((vp = strchr(data.data, '\n')) != NULL)
*vp = '\0';
data.size = strlen((char *)data.data);
if (db->put(db, &key, &data, 0))
err(1, "record enter");
/* Restore to original values. */
data.data = (u_char *)&nbuf;
data.size = sizeof(NLIST);
}
}
munmap(filep, sst.st_size);
(void)close(fd);
return(0);
}
#endif /* DO_ELF */
static struct knlist_handlers {
int (*fn) __P((char *name, DB *db));
} nlist_fn[] = {
#ifdef DO_ELF
{ __elf_knlist },
#endif
#ifdef DO_AOUT
{ __aout_knlist },
#endif
};
void
create_knlist(name, db)
char *name;
DB *db;
{
int n, i;
for (i = 0; i < sizeof(nlist_fn)/sizeof(nlist_fn[0]); i++) {
n = (nlist_fn[i].fn)(name, db);
if (n != -1)
break;
}
}