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/* ----------------------------------------------------------------------- *
*
* Copyright 1998-2008 H. Peter Anvin - All Rights Reserved
* Copyright 2010 Intel Corporation; author: H. Peter Anvin
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* syslinux.c - Linux installer program for SYSLINUX
*
* This program now requires mtools. It turned out to be a lot
* easier to deal with than dealing with needing mount privileges.
* We need device write permission anyway.
*/
#define _GNU_SOURCE
#include <alloca.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <inttypes.h>
#include <mntent.h>
#include <paths.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sysexits.h>
#include <syslog.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include "syslinux.h"
#include "libfat.h"
#include "setadv.h"
#include "syslxopt.h"
#include "syslxfs.h"
char *program; /* Name of program */
pid_t mypid;
void __attribute__ ((noreturn)) die(const char *msg)
{
fprintf(stderr, "%s: %s\n", program, msg);
exit(1);
}
void __attribute__ ((noreturn)) die_err(const char *msg)
{
fprintf(stderr, "%s: %s: %s\n", program, msg, strerror(errno));
exit(1);
}
/*
* read/write wrapper functions
*/
ssize_t xpread(int fd, void *buf, size_t count, off_t offset)
{
char *bufp = (char *)buf;
ssize_t rv;
ssize_t done = 0;
while (count) {
rv = pread(fd, bufp, count, offset);
if (rv == 0) {
die("short read");
} else if (rv == -1) {
if (errno == EINTR) {
continue;
} else {
die(strerror(errno));
}
} else {
bufp += rv;
offset += rv;
done += rv;
count -= rv;
}
}
return done;
}
ssize_t xpwrite(int fd, const void *buf, size_t count, off_t offset)
{
const char *bufp = (const char *)buf;
ssize_t rv;
ssize_t done = 0;
while (count) {
rv = pwrite(fd, bufp, count, offset);
if (rv == 0) {
die("short write");
} else if (rv == -1) {
if (errno == EINTR) {
continue;
} else {
die(strerror(errno));
}
} else {
bufp += rv;
offset += rv;
done += rv;
count -= rv;
}
}
return done;
}
/*
* Version of the read function suitable for libfat
*/
int libfat_xpread(intptr_t pp, void *buf, size_t secsize,
libfat_sector_t sector)
{
off_t offset = (off_t) sector * secsize + opt.offset;
return xpread(pp, buf, secsize, offset);
}
int main(int argc, char *argv[])
{
static unsigned char sectbuf[SECTOR_SIZE];
int dev_fd;
struct stat st;
int status;
const char *tmpdir;
char *mtools_conf;
int mtc_fd;
FILE *mtc, *mtp;
struct libfat_filesystem *fs;
libfat_sector_t s, *secp;
libfat_sector_t *sectors;
int32_t ldlinux_cluster;
int nsectors;
const char *errmsg;
int ldlinux_sectors, patch_sectors;
int i;
(void)argc; /* Unused */
mypid = getpid();
program = argv[0];
parse_options(argc, argv, MODE_SYSLINUX);
if (!opt.device)
usage(EX_USAGE, MODE_SYSLINUX);
if (opt.sectors || opt.heads || opt.reset_adv || opt.set_once
|| (opt.update_only > 0) || opt.menu_save) {
fprintf(stderr,
"At least one specified option not yet implemented"
" for this installer.\n");
exit(1);
}
/*
* Temp directory of choice...
*/
tmpdir = getenv("TMPDIR");
if (!tmpdir) {
#ifdef P_tmpdir
tmpdir = P_tmpdir;
#elif defined(_PATH_TMP)
tmpdir = _PATH_TMP;
#else
tmpdir = "/tmp";
#endif
}
/*
* First make sure we can open the device at all, and that we have
* read/write permission.
*/
dev_fd = open(opt.device, O_RDWR);
if (dev_fd < 0 || fstat(dev_fd, &st) < 0) {
die_err(opt.device);
exit(1);
}
if (!opt.force && !S_ISBLK(st.st_mode) && !S_ISREG(st.st_mode)) {
fprintf(stderr,
"%s: not a block device or regular file (use -f to override)\n",
opt.device);
exit(1);
}
xpread(dev_fd, sectbuf, SECTOR_SIZE, opt.offset);
/*
* Check to see that what we got was indeed an MS-DOS boot sector/superblock
*/
if ((errmsg = syslinux_check_bootsect(sectbuf, NULL))) {
die(errmsg);
}
/*
* Create an mtools configuration file
*/
if (asprintf(&mtools_conf, "%s//syslinux-mtools-XXXXXX", tmpdir) < 0 ||
!mtools_conf)
die_err(tmpdir);
mtc_fd = mkstemp(mtools_conf);
if (mtc_fd < 0 || !(mtc = fdopen(mtc_fd, "w")))
die_err(mtools_conf);
fprintf(mtc,
/* These are needed for some flash memories */
"MTOOLS_SKIP_CHECK=1\n"
"MTOOLS_FAT_COMPATIBILITY=1\n"
"drive s:\n"
" file=\"/proc/%lu/fd/%d\"\n"
" offset=%llu\n",
(unsigned long)mypid,
dev_fd, (unsigned long long)opt.offset);
if (ferror(mtc) || fclose(mtc))
die_err(mtools_conf);
/*
* Run mtools to create the LDLINUX.SYS file
*/
if (setenv("MTOOLSRC", mtools_conf, 1)) {
perror(program);
exit(1);
}
/*
* Create a vacuous ADV in memory. This should be smarter.
*/
syslinux_reset_adv(syslinux_adv);
/* This command may fail legitimately */
status = system("mattrib -h -r -s s:/ldlinux.sys 2>/dev/null");
(void)status; /* Keep _FORTIFY_SOURCE happy */
mtp = popen("mcopy -D o -D O -o - s:/ldlinux.sys", "w");
if (!mtp ||
fwrite(syslinux_ldlinux, 1, syslinux_ldlinux_len, mtp)
!= syslinux_ldlinux_len ||
fwrite(syslinux_adv, 1, 2 * ADV_SIZE, mtp)
!= 2 * ADV_SIZE ||
(status = pclose(mtp), !WIFEXITED(status) || WEXITSTATUS(status))) {
die("failed to create ldlinux.sys");
}
/*
* Now, use libfat to create a block map
*/
ldlinux_sectors = (syslinux_ldlinux_len + 2 * ADV_SIZE
+ SECTOR_SIZE - 1) >> SECTOR_SHIFT;
sectors = calloc(ldlinux_sectors, sizeof *sectors);
fs = libfat_open(libfat_xpread, dev_fd);
ldlinux_cluster = libfat_searchdir(fs, 0, "LDLINUX SYS", NULL);
secp = sectors;
nsectors = 0;
s = libfat_clustertosector(fs, ldlinux_cluster);
while (s && nsectors < ldlinux_sectors) {
*secp++ = s;
nsectors++;
s = libfat_nextsector(fs, s);
}
libfat_close(fs);
/* Patch ldlinux.sys and the boot sector */
i = syslinux_patch(sectors, nsectors, opt.stupid_mode, opt.raid_mode,
opt.directory, NULL);
patch_sectors = (i + SECTOR_SIZE - 1) >> SECTOR_SHIFT;
/* Write the now-patched first sectors of ldlinux.sys */
for (i = 0; i < patch_sectors; i++) {
xpwrite(dev_fd, syslinux_ldlinux + i * SECTOR_SIZE, SECTOR_SIZE,
opt.offset + ((off_t) sectors[i] << SECTOR_SHIFT));
}
/* Move ldlinux.sys to the desired location */
if (opt.directory) {
char target_file[4096], command[5120];
char *cp = target_file, *ep = target_file + sizeof target_file - 16;
const char *sd;
int slash = 1;
cp += sprintf(cp, "'s:/");
for (sd = opt.directory; *sd; sd++) {
if (*sd == '/' || *sd == '\\') {
if (slash)
continue; /* Remove duplicated slashes */
slash = 1;
} else if (*sd == '\'' || *sd == '!') {
slash = 0;
if (cp < ep)
*cp++ = '\'';
if (cp < ep)
*cp++ = '\\';
if (cp < ep)
*cp++ = *sd;
if (cp < ep)
*cp++ = '\'';
continue;
} else {
slash = 0;
}
if (cp < ep)
*cp++ = *sd;
}
if (!slash)
*cp++ = '/';
strcpy(cp, "ldlinux.sys'");
/* This command may fail legitimately */
sprintf(command, "mattrib -h -r -s %s 2>/dev/null", target_file);
status = system(command);
(void)status; /* Keep _FORTIFY_SOURCE happy */
sprintf(command, "mmove -D o -D O s:/ldlinux.sys %s", target_file);
status = system(command);
if (!WIFEXITED(status) || WEXITSTATUS(status)) {
fprintf(stderr,
"%s: warning: unable to move ldlinux.sys\n", program);
status = system("mattrib +r +h +s s:/ldlinux.sys");
} else {
sprintf(command, "mattrib +r +h +s %s", target_file);
status = system(command);
}
} else {
status = system("mattrib +r +h +s s:/ldlinux.sys");
}
if (!WIFEXITED(status) || WEXITSTATUS(status)) {
fprintf(stderr,
"%s: warning: failed to set system bit on ldlinux.sys\n",
program);
}
/*
* Cleanup
*/
unlink(mtools_conf);
/*
* To finish up, write the boot sector
*/
/* Read the superblock again since it might have changed while mounted */
xpread(dev_fd, sectbuf, SECTOR_SIZE, opt.offset);
/* Copy the syslinux code into the boot sector */
syslinux_make_bootsect(sectbuf, VFAT);
/* Write new boot sector */
xpwrite(dev_fd, sectbuf, SECTOR_SIZE, opt.offset);
close(dev_fd);
sync();
/* Done! */
return 0;
}