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authorhpa <hpa>2004-12-15 10:14:39 +0000
committerhpa <hpa>2004-12-15 10:14:39 +0000
commit7be70022dd3ae138998fc7185351b9b49ad9a9b2 (patch)
tree2599a8ede407eec131228fb607a52e22145ba1f9 /unix
parent4912df96419eff85394da1160bcb19a4dd2c1c59 (diff)
downloadsyslinux-elf-7be70022dd3ae138998fc7185351b9b49ad9a9b2.tar.gz
syslinux-elf-7be70022dd3ae138998fc7185351b9b49ad9a9b2.tar.xz
syslinux-elf-7be70022dd3ae138998fc7185351b9b49ad9a9b2.zip
Prepping for new 2.20 version: rewrite main syslinux program to support
FAT32 and EDD, and a new cleaner installer infrastructure.
Diffstat (limited to 'unix')
-rw-r--r--unix/Makefile39
-rw-r--r--unix/syslinux.c487
2 files changed, 526 insertions, 0 deletions
diff --git a/unix/Makefile b/unix/Makefile
new file mode 100644
index 00000000..9ba5e554
--- /dev/null
+++ b/unix/Makefile
@@ -0,0 +1,39 @@
+CC = gcc
+OPTFLAGS = -g -O
+INCLUDES = -I. -I.. -I../libfat
+CFLAGS = -W -Wall -D_FILE_OFFSET_BITS=64 $(OPTFLAGS) $(INCLUDES)
+LDFLAGS =
+
+SRCS = syslinux.c ../syslxmod.c ../bootsect_bin.c ../ldlinux_bin.c $(wildcard ../libfat/*.c)
+OBJS = $(patsubst %.c,%.o,$(notdir $(SRCS)))
+
+.SUFFIXES: .c .o .i .s .S
+
+VPATH = .:..:../libfat
+
+all: installer
+
+tidy:
+ -rm -f *.o *.i *.s *.a .*.d
+
+clean: tidy
+ -rm -f syslinux
+
+spotless: clean
+
+installer: syslinux
+
+syslinux: $(OBJS)
+ $(CC) $(LDFLAGS) -o $@ $^
+
+%.o: %.c
+ $(CC) -Wp,-MT,$@,-MMD,.$@.d $(CFLAGS) -c -o $@ $<
+%.i: %.c
+ $(CC) $(CFLAGS) -E -o $@ $<
+%.s: %.c
+ $(CC) $(CFLAGS) -S -o $@ $<
+
+-include .*.d
+
+
+
diff --git a/unix/syslinux.c b/unix/syslinux.c
new file mode 100644
index 00000000..182e1bf9
--- /dev/null
+++ b/unix/syslinux.c
@@ -0,0 +1,487 @@
+#ident "$Id$"
+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright 1998-2004 H. Peter Anvin - All Rights Reserved
+ *
+ * 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 ought to be portable. I hope so, at least.
+ *
+ * This is an alternate version of the installer which doesn't require
+ * mtools, but requires root privilege.
+ */
+
+#ifdef __KLIBC__
+# define DO_DIRECT_MOUNT 1 /* Call mount(2) directly */
+#else
+# define DO_DIRECT_MOUNT 0 /* Call /bin/mount instead */
+#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 "syslinux.h"
+#include "libfat.h"
+
+#if DO_DIRECT_MOUNT
+
+# include <linux/loop.h>
+
+#else
+
+# include <paths.h>
+# ifndef _PATH_MOUNT
+# define _PATH_MOUNT "/bin/mount"
+# endif
+# ifndef _PATH_UMOUNT
+# define _PATH_UMOUNT "/bin/umount"
+# endif
+
+#endif
+
+const char *program; /* Name of program */
+const char *device; /* Device to install to */
+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)) usage(void)
+{
+ fprintf(stderr, "Usage: %s [-sf] [-o offset] device\n", program);
+ exit(1);
+}
+
+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);
+}
+
+/*
+ * read/write wrapper functions
+ */
+ssize_t xpread(int fd, void *buf, size_t count, off_t offset)
+{
+ ssize_t rv;
+ ssize_t done = 0;
+
+ while ( count ) {
+ rv = pread(fd, buf, count, offset);
+ if ( rv == 0 ) {
+ die("short read");
+ } else if ( rv == -1 ) {
+ if ( errno == EINTR ) {
+ continue;
+ } else {
+ perror(program);
+ exit(1);
+ }
+ } else {
+ offset += rv;
+ done += rv;
+ count -= rv;
+ }
+ }
+
+ return done;
+}
+
+ssize_t xpwrite(int fd, void *buf, size_t count, off_t offset)
+{
+ ssize_t rv;
+ ssize_t done = 0;
+
+ while ( count ) {
+ rv = pwrite(fd, buf, count, offset);
+ if ( rv == 0 ) {
+ die("short write");
+ } else if ( rv == -1 ) {
+ if ( errno == EINTR ) {
+ continue;
+ } else {
+ perror(program);
+ exit(1);
+ }
+ } else {
+ offset += rv;
+ done += rv;
+ count -= rv;
+ }
+ }
+
+ return done;
+}
+
+/*
+ * Version of the read function suitable for libfat
+ */
+int libfat_xpread(void *pp, void *buf, size_t secsize, libfat_sector_t sector)
+{
+ off_t offset = (off_t)sector * secsize;
+ return xpread((int)pp, buf, secsize, offset);
+}
+
+int main(int argc, char *argv[])
+{
+ static unsigned char sectbuf[512];
+ unsigned char *dp;
+ const unsigned char *cdp;
+ int dev_fd, fd;
+ struct stat st;
+ int nb, left;
+ int err = 0;
+ pid_t f, w;
+ int status;
+ char mntname[64], devfdname[64];
+ char *ldlinux_name, **argp, *opt;
+ int force = 0; /* -f (force) option */
+ off_t offset = 0; /* -o (offset) option */
+ struct libfat_filesystem *fs;
+ libfat_sector_t s, *secp, sectors[65]; /* 65 is maximum possible */
+ int32_t ldlinux_cluster;
+ int nsectors;
+
+ (void)argc; /* Unused */
+
+ program = argv[0];
+ mypid = getpid();
+
+ device = NULL;
+
+ umask(077);
+
+ for ( argp = argv+1 ; *argp ; argp++ ) {
+ if ( **argp == '-' ) {
+ opt = *argp + 1;
+ if ( !*opt )
+ usage();
+
+ while ( *opt ) {
+ if ( *opt == 's' ) {
+ syslinux_make_stupid(); /* Use "safe, slow and stupid" code */
+ } else if ( *opt == 'f' ) {
+ force = 1; /* Force install */
+ } else if ( *opt == 'o' && argp[1] ) {
+ offset = (off_t)strtoull(*++argp, NULL, 0); /* Byte offset */
+ } else {
+ usage();
+ }
+ opt++;
+ }
+ } else {
+ if ( device )
+ usage();
+ device = *argp;
+ }
+ }
+
+ if ( !device )
+ usage();
+
+ /*
+ * First make sure we can open the device at all, and that we have
+ * read/write permission.
+ */
+ dev_fd = open(device, O_RDWR);
+ if ( dev_fd < 0 || fstat(dev_fd, &st) < 0 ) {
+ perror(device);
+ exit(1);
+ }
+
+ if ( !force && !S_ISBLK(st.st_mode) && !S_ISREG(st.st_mode) ) {
+ die("not a block device or regular file (use -f to override)");
+ }
+
+ if ( !force && offset != 0 && !S_ISREG(st.st_mode) ) {
+ die("not a regular file and an offset specified (use -f to override)");
+ }
+
+ xpread(dev_fd, sectbuf, 512, offset);
+ fsync(dev_fd);
+
+ /*
+ * Check to see that what we got was indeed an MS-DOS boot sector/superblock
+ */
+ if(!syslinux_check_bootsect(sectbuf,device)) {
+ 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("/tmp") ) {
+ perror(program);
+ 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 /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_DIRECT_MOUNT
+ if ( S_ISREG(st.st_mode) ) {
+ /* It's file, need to mount it loopback */
+ unsigned int n = 0;
+ struct loop_info64 loopinfo;
+
+ 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 = offset,
+ ioctl(loop_fd, LOOP_SET_STATUS64, &loopinfo)) )
+ die("cannot set up loopback device");
+ }
+ } else {
+ snprintf(devfdname, sizeof devfdname, "/proc/%lu/fd/%d",
+ (unsigned long)mypid, dev_fd);
+ }
+
+ if ( mount(devfdname, mntpath, "msdos",
+ MS_NOEXEC|MS_NOSUID, "umask=077,quiet") )
+ die("could not mount filesystem");
+
+#else
+
+ snprintf(devfdname, sizeof devfdname, "/proc/%lu/fd/%d",
+ (unsigned long)mypid, dev_fd);
+
+ f = fork();
+ if ( f < 0 ) {
+ perror(program);
+ rmdir(mntpath);
+ exit(1);
+ } else if ( f == 0 ) {
+ char mnt_opts[128];
+ if ( S_ISREG(st.st_mode) ) {
+ snprintf(mnt_opts, sizeof mnt_opts, "rw,nodev,noexec,loop,offset=%llu,umask=077,quiet",
+ (unsigned long long)offset);
+ } else {
+ snprintf(mnt_opts, sizeof mnt_opts, "rw,nodev,noexec,umask=077,quiet");
+ }
+ execl(_PATH_MOUNT, _PATH_MOUNT, "-t", "msdos", "-o", mnt_opts,\
+ devfdname, mntpath, NULL);
+ _exit(255); /* execl failed */
+ }
+
+ w = waitpid(f, &status, 0);
+ if ( w != f || status ) {
+ rmdir(mntpath);
+ exit(1); /* Mount failed */
+ }
+
+#endif
+ }
+
+ ldlinux_name = alloca(strlen(mntpath)+13);
+ if ( !ldlinux_name ) {
+ perror(program);
+ err = 1;
+ goto umount;
+ }
+ sprintf(ldlinux_name, "%s/ldlinux.sys", mntpath);
+
+ unlink(ldlinux_name);
+ fd = open(ldlinux_name, O_WRONLY|O_CREAT|O_TRUNC, 0444);
+ if ( fd < 0 ) {
+ perror(device);
+ err = 1;
+ goto umount;
+ }
+
+ cdp = syslinux_ldlinux;
+ left = syslinux_ldlinux_len;
+ while ( left ) {
+ nb = write(fd, cdp, left);
+ if ( nb == -1 && errno == EINTR )
+ continue;
+ else if ( nb <= 0 ) {
+ perror(device);
+ err = 1;
+ goto umount;
+ }
+
+ dp += nb;
+ left -= nb;
+ }
+
+ /*
+ * I don't understand why I need this. Does the DOS filesystems
+ * not honour the mode passed to open()?
+ */
+ fchmod(fd, 0400);
+
+ close(fd);
+
+ sync();
+
+umount:
+#if DO_DIRECT_MOUNT
+
+ 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
+
+ f = fork();
+ 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
+
+ sync();
+ rmdir(mntpath);
+
+ if ( err )
+ exit(err);
+
+ /*
+ * Now, use libfat to create a block map. This probably
+ * should be changed to use ioctl(...,FIBMAP,...) since
+ * this is supposed to be a simple, privileged version
+ * of the installer.
+ */
+ fs = libfat_open(libfat_xpread, (void *)dev_fd);
+ ldlinux_cluster = libfat_searchdir(fs, 0, "LDLINUX SYS", NULL);
+ secp = sectors;
+ nsectors = 0;
+ s = libfat_clustertosector(fs, ldlinux_cluster);
+ while ( s && nsectors < 65 ) {
+ *secp++ = s;
+ nsectors++;
+ s = libfat_nextsector(fs, s);
+ }
+ libfat_close(fs);
+
+ /*
+ * Patch ldlinux.sys and the boot sector
+ */
+ syslinux_patch(sectors, nsectors);
+
+ /*
+ * Write the now-patched first sector of ldlinux.sys
+ */
+ xpwrite(dev_fd, syslinux_ldlinux, 512, offset + ((off_t)sectors[0] << 9));
+
+ /*
+ * To finish up, write the boot sector
+ */
+
+ /* Read the superblock again since it might have changed while mounted */
+ xpread(dev_fd, sectbuf, 512, offset);
+
+ /* Copy the syslinux code into the boot sector */
+ syslinux_make_bootsect(sectbuf);
+
+ /* Write new boot sector */
+ xpwrite(dev_fd, sectbuf, 512, offset);
+
+ close(dev_fd);
+ sync();
+
+ /* Done! */
+
+ return 0;
+}
+