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/* $OpenBSD: a.out.c,v 1.5 2006/04/02 00:48:35 deraadt Exp $ */
/* $NetBSD: a.out.c,v 1.1 1999/06/13 12:54:40 mrg Exp $ */
/*
* Copyright (c) 1993 Terrence R. Lambert.
* 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 Terrence R. Lambert.
* 4. The name Terrence R. Lambert may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``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 TERRENCE R. LAMBERT 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.
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/lkm.h>
#include <a.out.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include "modload.h"
/*
* Expected linker options:
*
* -A executable to link against
* -e entry point
* -o output file
* -T address to link to in hex (assumes it's a page boundry)
* <target> object file
*/
#define LINKCMD "ld -A %s -e _%s -o %s -T %p %s"
static struct exec sinfo_buf; /* buffer for loading */
extern int devfd, modfd;
extern struct lmc_resrv resrv;
extern int symtab;
void
a_out_linkcmd(char *buf, size_t len, const char *kernel,
const char *entry, const char *outfile, const void *address,
const char *object)
{
ssize_t n;
n = snprintf(buf, len, LINKCMD, kernel, entry,
outfile, address, object);
if (n < 0 || n >= len)
errx(1, "link command longer than %lu bytes", (u_long)len);
}
static int
a_out_read_header(int fd, struct exec *info_buf)
{
ssize_t n;
n = read(fd, info_buf, sizeof(*info_buf));
if (n < 0)
err(1, "failed reading %lu bytes", (u_long)sizeof(*info_buf));
if (n != sizeof(*info_buf)) {
if (debug)
fprintf(stderr, "failed to read %lu bytes",
(u_long)sizeof(*info_buf));
return -1;
}
/*
* Magic number...
*/
if (N_BADMAG(*info_buf))
errx(4, "not an a.out format file");
return 0;
}
int
a_out_mod_sizes(int fd, size_t *modsize, int *strtablen,
struct lmc_resrv *resrvp, struct stat *sp)
{
struct exec info_buf;
if (a_out_read_header(fd, &info_buf) < 0)
return -1;
/*
* Calculate the size of the module
*/
*modsize = info_buf.a_text + info_buf.a_data + info_buf.a_bss;
*strtablen = sp->st_size - N_STROFF(info_buf);
if (symtab) {
/*
* XXX TODO: grovel through symbol table looking for
* just the symbol table stuff from the new module,
* and skip the stuff from the kernel.
*/
resrvp->sym_size = info_buf.a_syms + *strtablen;
resrvp->sym_symsize = info_buf.a_syms;
} else
resrvp->sym_size = resrvp->sym_symsize = 0;
return (0);
}
void *
a_out_mod_load(int fd)
{
size_t b;
ssize_t n;
char buf[MODIOBUF];
/*
* Get the load module post load size... do this by reading the
* header and doing page counts.
*/
if (a_out_read_header(fd, &sinfo_buf) < 0)
return NULL;
/*
* Seek to the text offset to start loading...
*/
if (lseek(fd, N_TXTOFF(sinfo_buf), SEEK_SET) == -1)
err(12, "lseek");
/*
* Transfer the relinked module to kernel memory in chunks of
* MODIOBUF size at a time.
*/
b = sinfo_buf.a_text + sinfo_buf.a_data;
while (b) {
n = read(fd, buf, MIN(b, sizeof(buf)));
if (n < 0)
err(1, "while reading from prelinked module");
if (n == 0)
errx(1, "EOF while reading from prelinked module");
loadbuf(buf, n);
b -= n;
}
return (void*)sinfo_buf.a_entry;
}
void
a_out_mod_symload(int strtablen)
{
struct lmc_loadbuf ldbuf;
char buf[MODIOBUF];
int bytesleft, sz;
/*
* Seek to the symbol table to start loading it...
*/
if (lseek(modfd, N_SYMOFF(sinfo_buf), SEEK_SET) == -1)
err(12, "lseek");
/*
* we've fixed the symbol table entries, now load them
*/
for (bytesleft = sinfo_buf.a_syms; bytesleft > 0; bytesleft -= sz) {
sz = MIN(bytesleft, MODIOBUF);
if (read(modfd, buf, sz) != sz)
err(14, "read");
ldbuf.cnt = sz;
ldbuf.data = buf;
if (ioctl(devfd, LMLOADSYMS, &ldbuf) == -1)
err(11, "error transferring sym buffer");
}
/* and now read the string table and load it. */
for (bytesleft = strtablen; bytesleft > 0; bytesleft -= sz) {
sz = MIN(bytesleft, MODIOBUF);
if (read(modfd, buf, sz) != sz)
err(14, "read");
ldbuf.cnt = sz;
ldbuf.data = buf;
if (ioctl(devfd, LMLOADSYMS, &ldbuf) == -1)
err(11, "error transferring stringtable buffer");
}
}
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