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-rwxr-xr-xcontrib/syslinux-4.02/linux/syslinux.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/linux/syslinux.c b/contrib/syslinux-4.02/linux/syslinux.c
new file mode 100755
index 0000000..97b6a30
--- /dev/null
+++ b/contrib/syslinux-4.02/linux/syslinux.c
@@ -0,0 +1,484 @@
+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright 1998-2008 H. Peter Anvin - All Rights Reserved
+ * Copyright 2009-2010 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 is Linux-specific by now.
+ *
+ * This is an alternate version of the installer which doesn't require
+ * mtools, but requires root privilege.
+ */
+
+/*
+ * If DO_DIRECT_MOUNT is 0, call mount(8)
+ * If DO_DIRECT_MOUNT is 1, call mount(2)
+ */
+#ifdef __KLIBC__
+# define DO_DIRECT_MOUNT 1
+#else
+# define DO_DIRECT_MOUNT 0 /* glibc has broken losetup ioctls */
+#endif
+
+#define _GNU_SOURCE
+#define _XOPEN_SOURCE 500 /* For pread() pwrite() */
+#define _FILE_OFFSET_BITS 64
+#include <alloca.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <paths.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/mount.h>
+
+#include "linuxioctl.h"
+
+#include <paths.h>
+#ifndef _PATH_MOUNT
+# define _PATH_MOUNT "/bin/mount"
+#endif
+#ifndef _PATH_UMOUNT
+# define _PATH_UMOUNT "/bin/umount"
+#endif
+#ifndef _PATH_TMP
+# define _PATH_TMP "/tmp/"
+#endif
+
+#include "syslinux.h"
+
+#if DO_DIRECT_MOUNT
+# include <linux/loop.h>
+#endif
+
+#include <getopt.h>
+#include <sysexits.h>
+#include "syslxcom.h"
+#include "setadv.h"
+#include "syslxopt.h" /* unified options */
+
+extern const char *program; /* Name of program */
+
+pid_t mypid;
+char *mntpath = NULL; /* Path on which to mount */
+
+#if DO_DIRECT_MOUNT
+int loop_fd = -1; /* Loop device */
+#endif
+
+void __attribute__ ((noreturn)) die(const char *msg)
+{
+ fprintf(stderr, "%s: %s\n", program, msg);
+
+#if DO_DIRECT_MOUNT
+ if (loop_fd != -1) {
+ ioctl(loop_fd, LOOP_CLR_FD, 0); /* Free loop device */
+ close(loop_fd);
+ loop_fd = -1;
+ }
+#endif
+
+ if (mntpath)
+ unlink(mntpath);
+
+ exit(1);
+}
+
+/*
+ * Mount routine
+ */
+int do_mount(int dev_fd, int *cookie, const char *mntpath, const char *fstype)
+{
+ struct stat st;
+
+ (void)cookie;
+
+ if (fstat(dev_fd, &st) < 0)
+ return errno;
+
+#if DO_DIRECT_MOUNT
+ {
+ if (!S_ISBLK(st.st_mode)) {
+ /* It's file, need to mount it loopback */
+ unsigned int n = 0;
+ struct loop_info64 loopinfo;
+ int loop_fd;
+
+ for (n = 0; loop_fd < 0; n++) {
+ snprintf(devfdname, sizeof devfdname, "/dev/loop%u", n);
+ loop_fd = open(devfdname, O_RDWR);
+ if (loop_fd < 0 && errno == ENOENT) {
+ die("no available loopback device!");
+ }
+ if (ioctl(loop_fd, LOOP_SET_FD, (void *)dev_fd)) {
+ close(loop_fd);
+ loop_fd = -1;
+ if (errno != EBUSY)
+ die("cannot set up loopback device");
+ else
+ continue;
+ }
+
+ if (ioctl(loop_fd, LOOP_GET_STATUS64, &loopinfo) ||
+ (loopinfo.lo_offset = opt.offset,
+ ioctl(loop_fd, LOOP_SET_STATUS64, &loopinfo)))
+ die("cannot set up loopback device");
+ }
+
+ *cookie = loop_fd;
+ } else {
+ snprintf(devfdname, sizeof devfdname, "/proc/%lu/fd/%d",
+ (unsigned long)mypid, dev_fd);
+ *cookie = -1;
+ }
+
+ return mount(devfdname, mntpath, fstype,
+ MS_NOEXEC | MS_NOSUID, "umask=077,quiet");
+ }
+#else
+ {
+ char devfdname[128], mnt_opts[128];
+ pid_t f, w;
+ int status;
+
+ snprintf(devfdname, sizeof devfdname, "/proc/%lu/fd/%d",
+ (unsigned long)mypid, dev_fd);
+
+ f = fork();
+ if (f < 0) {
+ return -1;
+ } else if (f == 0) {
+ if (!S_ISBLK(st.st_mode)) {
+ snprintf(mnt_opts, sizeof mnt_opts,
+ "rw,nodev,noexec,loop,offset=%llu,umask=077,quiet",
+ (unsigned long long)opt.offset);
+ } else {
+ snprintf(mnt_opts, sizeof mnt_opts,
+ "rw,nodev,noexec,umask=077,quiet");
+ }
+ execl(_PATH_MOUNT, _PATH_MOUNT, "-t", fstype, "-o", mnt_opts,
+ devfdname, mntpath, NULL);
+ _exit(255); /* execl failed */
+ }
+
+ w = waitpid(f, &status, 0);
+ return (w != f || status) ? -1 : 0;
+ }
+#endif
+}
+
+/*
+ * umount routine
+ */
+void do_umount(const char *mntpath, int cookie)
+{
+#if DO_DIRECT_MOUNT
+ int loop_fd = cookie;
+
+ if (umount2(mntpath, 0))
+ die("could not umount path");
+
+ if (loop_fd != -1) {
+ ioctl(loop_fd, LOOP_CLR_FD, 0); /* Free loop device */
+ close(loop_fd);
+ loop_fd = -1;
+ }
+#else
+ pid_t f = fork();
+ pid_t w;
+ int status;
+ (void)cookie;
+
+ if (f < 0) {
+ perror("fork");
+ exit(1);
+ } else if (f == 0) {
+ execl(_PATH_UMOUNT, _PATH_UMOUNT, mntpath, NULL);
+ }
+
+ w = waitpid(f, &status, 0);
+ if (w != f || status) {
+ exit(1);
+ }
+#endif
+}
+
+/*
+ * Modify the ADV of an existing installation
+ */
+int modify_existing_adv(const char *path)
+{
+ if (opt.reset_adv)
+ syslinux_reset_adv(syslinux_adv);
+ else if (read_adv(path, "ldlinux.sys") < 0)
+ return 1;
+
+ if (modify_adv() < 0)
+ return 1;
+
+ if (write_adv(path, "ldlinux.sys") < 0)
+ return 1;
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ static unsigned char sectbuf[SECTOR_SIZE];
+ int dev_fd, fd;
+ struct stat st;
+ int err = 0;
+ char mntname[128];
+ char *ldlinux_name;
+ char *ldlinux_path;
+ char *subdir;
+ sector_t *sectors = NULL;
+ int ldlinux_sectors = (boot_image_len + SECTOR_SIZE - 1) >> SECTOR_SHIFT;
+ const char *errmsg;
+ int mnt_cookie;
+ int patch_sectors;
+ int i;
+
+ mypid = getpid();
+ umask(077);
+ parse_options(argc, argv, MODE_SYSLINUX);
+
+ /* Note: subdir is guaranteed to start and end in / */
+ if (opt.directory && opt.directory[0]) {
+ int len = strlen(opt.directory);
+ int rv = asprintf(&subdir, "%s%s%s",
+ opt.directory[0] == '/' ? "" : "/",
+ opt.directory,
+ opt.directory[len-1] == '/' ? "" : "/");
+ if (rv < 0 || !subdir) {
+ perror(program);
+ exit(1);
+ }
+ } else {
+ subdir = "/";
+ }
+
+ if (!opt.device || opt.install_mbr || opt.activate_partition)
+ usage(EX_USAGE, MODE_SYSLINUX);
+
+ /*
+ * 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) {
+ perror(opt.device);
+ exit(1);
+ }
+
+ if (!S_ISBLK(st.st_mode) && !S_ISREG(st.st_mode) && !S_ISCHR(st.st_mode)) {
+ die("not a device or regular file");
+ }
+
+ if (opt.offset && S_ISBLK(st.st_mode)) {
+ die("can't combine an offset with a block device");
+ }
+
+ fs_type = VFAT;
+ xpread(dev_fd, sectbuf, SECTOR_SIZE, opt.offset);
+ fsync(dev_fd);
+
+ /*
+ * Check to see that what we got was indeed an MS-DOS boot sector/superblock
+ */
+ if ((errmsg = syslinux_check_bootsect(sectbuf))) {
+ fprintf(stderr, "%s: %s\n", opt.device, errmsg);
+ exit(1);
+ }
+
+ /*
+ * Now mount the device.
+ */
+ if (geteuid()) {
+ die("This program needs root privilege");
+ } else {
+ int i = 0;
+ struct stat dst;
+ int rv;
+
+ /* We're root or at least setuid.
+ Make a temp dir and pass all the gunky options to mount. */
+
+ if (chdir(_PATH_TMP)) {
+ fprintf(stderr, "%s: Cannot access the %s directory.\n",
+ program, _PATH_TMP);
+ exit(1);
+ }
+#define TMP_MODE (S_IXUSR|S_IWUSR|S_IXGRP|S_IWGRP|S_IWOTH|S_IXOTH|S_ISVTX)
+
+ if (stat(".", &dst) || !S_ISDIR(dst.st_mode) ||
+ (dst.st_mode & TMP_MODE) != TMP_MODE) {
+ die("possibly unsafe " _PATH_TMP " permissions");
+ }
+
+ for (i = 0;; i++) {
+ snprintf(mntname, sizeof mntname, "syslinux.mnt.%lu.%d",
+ (unsigned long)mypid, i);
+
+ if (lstat(mntname, &dst) != -1 || errno != ENOENT)
+ continue;
+
+ rv = mkdir(mntname, 0000);
+
+ if (rv == -1) {
+ if (errno == EEXIST || errno == EINTR)
+ continue;
+ perror(program);
+ exit(1);
+ }
+
+ if (lstat(mntname, &dst) || dst.st_mode != (S_IFDIR | 0000) ||
+ dst.st_uid != 0) {
+ die("someone is trying to symlink race us!");
+ }
+ break; /* OK, got something... */
+ }
+
+ mntpath = mntname;
+ }
+
+ if (do_mount(dev_fd, &mnt_cookie, mntpath, "vfat") &&
+ do_mount(dev_fd, &mnt_cookie, mntpath, "msdos")) {
+ rmdir(mntpath);
+ die("mount failed");
+ }
+
+ ldlinux_path = alloca(strlen(mntpath) + strlen(subdir) + 1);
+ sprintf(ldlinux_path, "%s%s", mntpath, subdir);
+
+ ldlinux_name = alloca(strlen(ldlinux_path) + 14);
+ if (!ldlinux_name) {
+ perror(program);
+ err = 1;
+ goto umount;
+ }
+ sprintf(ldlinux_name, "%sldlinux.sys", ldlinux_path);
+
+ /* update ADV only ? */
+ if (opt.update_only == -1) {
+ if (opt.reset_adv || opt.set_once) {
+ modify_existing_adv(ldlinux_path);
+ do_umount(mntpath, mnt_cookie);
+ sync();
+ rmdir(mntpath);
+ exit(0);
+ } else {
+ fprintf(stderr, "%s: please specify --install or --update for the future\n", argv[0]);
+ opt.update_only = 0;
+ }
+ }
+
+ /* Read a pre-existing ADV, if already installed */
+ if (opt.reset_adv)
+ syslinux_reset_adv(syslinux_adv);
+ else if (read_adv(ldlinux_path, "ldlinux.sys") < 0)
+ syslinux_reset_adv(syslinux_adv);
+ if (modify_adv() < 0)
+ exit(1);
+
+ if ((fd = open(ldlinux_name, O_RDONLY)) >= 0) {
+ uint32_t zero_attr = 0;
+ ioctl(fd, FAT_IOCTL_SET_ATTRIBUTES, &zero_attr);
+ close(fd);
+ }
+
+ unlink(ldlinux_name);
+ fd = open(ldlinux_name, O_WRONLY | O_CREAT | O_TRUNC, 0444);
+ if (fd < 0) {
+ perror(opt.device);
+ err = 1;
+ goto umount;
+ }
+
+ /* Write it the first time */
+ if (xpwrite(fd, boot_image, boot_image_len, 0) != (int)boot_image_len ||
+ xpwrite(fd, syslinux_adv, 2 * ADV_SIZE,
+ boot_image_len) != 2 * ADV_SIZE) {
+ fprintf(stderr, "%s: write failure on %s\n", program, ldlinux_name);
+ exit(1);
+ }
+
+ fsync(fd);
+ /*
+ * Set the attributes
+ */
+ {
+ uint32_t attr = 0x07; /* Hidden+System+Readonly */
+ ioctl(fd, FAT_IOCTL_SET_ATTRIBUTES, &attr);
+ }
+
+ /*
+ * Create a block map.
+ */
+ ldlinux_sectors += 2; /* 2 ADV sectors */
+ sectors = calloc(ldlinux_sectors, sizeof *sectors);
+ if (sectmap(fd, sectors, ldlinux_sectors)) {
+ perror("bmap");
+ exit(1);
+ }
+ close(fd);
+ sync();
+
+umount:
+ do_umount(mntpath, mnt_cookie);
+ sync();
+ rmdir(mntpath);
+
+ if (err)
+ exit(err);
+
+ /*
+ * Patch ldlinux.sys and the boot sector
+ */
+ i = syslinux_patch(sectors, ldlinux_sectors, opt.stupid_mode,
+ opt.raid_mode, subdir, 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, boot_image + i * SECTOR_SIZE, SECTOR_SIZE,
+ opt.offset + ((off_t) sectors[i] << SECTOR_SHIFT));
+ }
+
+ /*
+ * 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);
+
+ /* Write new boot sector */
+ xpwrite(dev_fd, sectbuf, SECTOR_SIZE, opt.offset);
+
+ close(dev_fd);
+ sync();
+
+ /* Done! */
+
+ return 0;
+}
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