freebsd-dev/usr.bin/brandelf/brandelf.c
1999-08-28 01:08:13 +00:00

146 lines
3.8 KiB
C

/*-
* Copyright (c) 1996 Søren Schmidt
* 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
* in this position and unchanged.
* 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. The name of the author may not be used to endorse or promote products
* derived from this software withough 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.
*
* $FreeBSD$
*/
#include <elf.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
static int iselftype(const char *);
static void usage __P((void));
int
main(int argc, char **argv)
{
const char *type = "FreeBSD";
int retval = 0;
int ch, change = 0, verbose = 0, force = 0;
while ((ch = getopt(argc, argv, "ft:v")) != -1)
switch (ch) {
case 'f':
force = 1;
break;
case 'v':
verbose = 1;
break;
case 't':
change = 1;
type = optarg;
break;
default:
usage();
}
argc -= optind;
argv += optind;
if (!argc)
errx(1, "no file(s) specified");
if (!force && !iselftype(type))
errx(1, "invalid ELF type '%s'", type);
while (argc) {
int fd;
char buffer[EI_NIDENT];
char string[(EI_NIDENT-EI_BRAND)+1];
if ((fd = open(argv[0], change? O_RDWR: O_RDONLY, 0)) < 0) {
warn("error opening file %s", argv[0]);
retval = 1;
goto fail;
}
if (read(fd, buffer, EI_NIDENT) < EI_NIDENT) {
warnx("file '%s' too short", argv[0]);
retval = 1;
goto fail;
}
if (buffer[0] != ELFMAG0 || buffer[1] != ELFMAG1 ||
buffer[2] != ELFMAG2 || buffer[3] != ELFMAG3) {
warnx("file '%s' is not ELF format", argv[0]);
retval = 1;
goto fail;
}
if (!change) {
bzero(string, sizeof(string));
strncpy(string, &buffer[EI_BRAND], EI_NIDENT-EI_BRAND);
if (strlen(string)) {
fprintf(stdout,
"File '%s' is of brand '%s'.\n",
argv[0], string);
if (!force && !iselftype(string))
warnx("Brand '%s' is unknown",
string);
}
else
fprintf(stdout, "File '%s' has no branding.\n",
argv[0]);
}
else {
strncpy(&buffer[EI_BRAND], type, EI_NIDENT-EI_BRAND);
lseek(fd, 0, SEEK_SET);
if (write(fd, buffer, EI_NIDENT) != EI_NIDENT) {
warnx("error writing %s", argv[0]);
retval = 1;
goto fail;
}
}
fail:
argc--;
argv++;
}
return retval;
}
static void
usage()
{
fprintf(stderr, "usage: brandelf [-f] [-v] [-t string] file ...\n");
exit(1);
}
static int
iselftype(const char *elftype) {
/* XXX - any more types? */
const char *elftypes[] = { "FreeBSD", "Linux", "SVR4" };
int elfwalk;
for (elfwalk = 0;
elfwalk < sizeof(elftypes)/sizeof(elftypes[0]);
elfwalk++)
if (strcmp(elftype, elftypes[elfwalk]) == 0)
return 1;
return 0;
}