/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following functions.
- usage
- print_node
- romfs_read
- cramfs_iget
- iget
- iput
- read_super
- uncompress_block
- change_file_status
- do_symlink
- do_special_inode
- do_uncompress
- expand_fs
- main
/*
* cramfsck - check a cramfs file system
*
* Copyright (C) 2000-2001 Transmeta Corporation
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* 1999/12/03: Linus Torvalds (cramfs tester and unarchive program)
* 2000/06/03: Daniel Quinlan (CRC and length checking program)
* 2000/06/04: Daniel Quinlan (merged programs, added options, support
* for special files, preserve permissions and
* ownership, cramfs superblock v2, bogus mode
* test, pathname length test, etc.)
* 2000/06/06: Daniel Quinlan (support for holes, pretty-printing,
* symlink size test)
* 2000/07/11: Daniel Quinlan (file length tests, start at offset 0 or 512,
* fsck-compatible exit codes)
* 2000/07/15: Daniel Quinlan (initial support for block devices)
*/
/* compile-time options */
#define INCLUDE_FS_TESTS /* include cramfs checking and extraction */
#include <sys/types.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/fcntl.h>
#include <dirent.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <assert.h>
#include <getopt.h>
#include <sys/sysmacros.h>
#include <utime.h>
#include <sys/ioctl.h>
#define _LINUX_STRING_H_
#include <linux/fs.h>
#include <linux/cramfs_fs.h>
#include <zlib.h>
static const char *progname = "cramfsck";
static int fd; /* ROM image file descriptor */
static char *filename; /* ROM image filename */
struct cramfs_super *super; /* just find the cramfs superblock once */
static int opt_verbose = 0; /* 1 = verbose (-v), 2+ = very verbose (-vv) */
#ifdef INCLUDE_FS_TESTS
static int opt_extract = 0; /* extract cramfs (-x) */
char *extract_dir = NULL; /* extraction directory (-x) */
unsigned long start_inode = 1 << 28; /* start of first non-root inode */
unsigned long end_inode = 0; /* end of the directory structure */
unsigned long start_data = 1 << 28; /* start of the data (256 MB = max) */
unsigned long end_data = 0; /* end of the data */
/* true? cramfs_super < start_inode < end_inode <= start_data <= end_data */
static uid_t euid; /* effective UID */
#define PAD_SIZE 512
#define PAGE_CACHE_SIZE (4096)
/* Guarantee access to at least 8kB at a time */
#define ROMBUFFER_BITS 13
#define ROMBUFFERSIZE (1 << ROMBUFFER_BITS)
#define ROMBUFFERMASK (ROMBUFFERSIZE-1)
static char read_buffer[ROMBUFFERSIZE * 2];
static unsigned long read_buffer_block = ~0UL;
/* Uncompressing data structures... */
static char outbuffer[PAGE_CACHE_SIZE*2];
z_stream stream;
#endif /* INCLUDE_FS_TESTS */
/* Input status of 0 to print help and exit without an error. */
static void usage(int status)
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{
FILE *stream = status ? stderr : stdout;
fprintf(stream, "usage: %s [-hv] [-x dir] file\n"
" -h print this help\n"
" -x dir extract into dir\n"
" -v be more verbose\n"
" file file to test\n", progname);
exit(status);
}
#ifdef INCLUDE_FS_TESTS
void print_node(char type, struct cramfs_inode *i, char *name)
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{
char info[10];
if (S_ISCHR(i->mode) || (S_ISBLK(i->mode))) {
/* major/minor numbers can be as high as 2^12 or 4096 */
snprintf(info, 10, "%4d,%4d", major(i->size), minor(i->size));
}
else {
/* size be as high as 2^24 or 16777216 */
snprintf(info, 10, "%9d", i->size);
}
printf("%c %04o %s %5d:%-3d %s\n",
type, i->mode & ~S_IFMT, info, i->uid, i->gid, name);
}
/*
* Create a fake "blocked" access
*/
static void *romfs_read(unsigned long offset)
/* [<][>][^][v][top][bottom][index][help] */
{
unsigned int block = offset >> ROMBUFFER_BITS;
if (block != read_buffer_block) {
read_buffer_block = block;
lseek(fd, block << ROMBUFFER_BITS, SEEK_SET);
read(fd, read_buffer, ROMBUFFERSIZE * 2);
}
return read_buffer + (offset & ROMBUFFERMASK);
}
static struct cramfs_inode *cramfs_iget(struct cramfs_inode * i)
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{
struct cramfs_inode *inode = malloc(sizeof(struct cramfs_inode));
*inode = *i;
return inode;
}
static struct cramfs_inode *iget(unsigned int ino)
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{
return cramfs_iget(romfs_read(ino));
}
void iput(struct cramfs_inode *inode)
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{
free(inode);
}
/*
* Return the offset of the root directory,
* or 0 if none.
*/
static struct cramfs_inode *read_super(void)
/* [<][>][^][v][top][bottom][index][help] */
{
unsigned long offset;
offset = super->root.offset << 2;
if (super->magic != CRAMFS_MAGIC)
return NULL;
if (memcmp(super->signature, CRAMFS_SIGNATURE, sizeof(super->signature)) != 0)
return NULL;
if (offset < sizeof(super))
return NULL;
return cramfs_iget(&super->root);
}
static int uncompress_block(void *src, int len)
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{
int err;
stream.next_in = src;
stream.avail_in = len;
stream.next_out = (unsigned char *) outbuffer;
stream.avail_out = PAGE_CACHE_SIZE*2;
inflateReset(&stream);
err = inflate(&stream, Z_FINISH);
if (err != Z_STREAM_END) {
fprintf(stderr, "%s: error %d while decompressing! %p(%d)\n",
filename, err, src, len);
exit(4);
}
return stream.total_out;
}
static void change_file_status(char *path, struct cramfs_inode *i)
/* [<][>][^][v][top][bottom][index][help] */
{
struct utimbuf epoch = { 0, 0 };
if (euid == 0) {
if (lchown(path, i->uid, i->gid) < 0) {
perror(path);
exit(8);
}
if (S_ISLNK(i->mode))
return;
if ((S_ISUID | S_ISGID) & i->mode) {
if (chmod(path, i->mode) < 0) {
perror(path);
exit(8);
}
}
}
if (S_ISLNK(i->mode))
return;
if (utime(path, &epoch) < 0) {
perror(path);
exit(8);
}
}
static void do_symlink(char *path, struct cramfs_inode *i)
/* [<][>][^][v][top][bottom][index][help] */
{
unsigned long offset = i->offset << 2;
unsigned long curr = offset + 4;
unsigned long next = *(u32 *) romfs_read(offset);
unsigned long size;
if (next > end_data) {
end_data = next;
}
size = uncompress_block(romfs_read(curr), next - curr);
if (size != i->size) {
fprintf(stderr, "%s: size error in symlink `%s'\n",
filename, path);
exit(4);
}
outbuffer[size] = 0;
if (opt_verbose) {
char *str;
str = malloc(strlen(outbuffer) + strlen(path) + 5);
strcpy(str, path);
strncat(str, " -> ", 4);
strncat(str, outbuffer, size);
print_node('l', i, str);
if (opt_verbose > 1) {
printf(" uncompressing block at %ld to %ld (%ld)\n", curr, next, next - curr);
}
}
if (opt_extract) {
symlink(outbuffer, path);
change_file_status(path, i);
}
}
static void do_special_inode(char *path, struct cramfs_inode *i)
/* [<][>][^][v][top][bottom][index][help] */
{
dev_t devtype = 0;
char type;
if (S_ISCHR(i->mode)) {
devtype = i->size;
type = 'c';
}
else if (S_ISBLK(i->mode)) {
devtype = i->size;
type = 'b';
}
else if (S_ISFIFO(i->mode))
type = 'p';
else if (S_ISSOCK(i->mode))
type = 's';
else {
fprintf(stderr, "%s: bogus mode on `%s' (%o)\n", filename, path, i->mode);
exit(4);
}
if (opt_verbose) {
print_node(type, i, path);
}
if (opt_extract) {
if (mknod(path, i->mode, devtype) < 0) {
perror(path);
exit(8);
}
change_file_status(path, i);
}
}
static void do_uncompress(int fd, unsigned long offset, unsigned long size)
/* [<][>][^][v][top][bottom][index][help] */
{
unsigned long curr = offset + 4 * ((size + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE);
do {
unsigned long out = PAGE_CACHE_SIZE;
unsigned long next = *(u32 *) romfs_read(offset);
if (next > end_data) {
end_data = next;
}
offset += 4;
if (curr == next) {
if (opt_verbose > 1) {
printf(" hole at %ld (%d)\n", curr, PAGE_CACHE_SIZE);
}
if (size < PAGE_CACHE_SIZE)
out = size;
memset(outbuffer, 0x00, out);
}
else {
if (opt_verbose > 1) {
printf(" uncompressing block at %ld to %ld (%ld)\n", curr, next, next - curr);
}
out = uncompress_block(romfs_read(curr), next - curr);
}
if (size >= PAGE_CACHE_SIZE) {
if (out != PAGE_CACHE_SIZE) {
fprintf(stderr, "%s: Non-block (%ld) bytes\n", filename, out);
exit(4);
}
} else {
if (out != size) {
fprintf(stderr, "%s: Non-size (%ld vs %ld) bytes\n", filename, out, size);
exit(4);
}
}
size -= out;
if (opt_extract) {
write(fd, outbuffer, out);
}
curr = next;
} while (size);
}
static void expand_fs(int pathlen, char *path, struct cramfs_inode *inode)
/* [<][>][^][v][top][bottom][index][help] */
{
if (S_ISDIR(inode->mode)) {
int count = inode->size;
unsigned long offset = inode->offset << 2;
char *newpath = malloc(pathlen + 256);
if (count > 0 && offset < start_inode) {
start_inode = offset;
}
/* XXX - need to check end_inode for empty case? */
memcpy(newpath, path, pathlen);
newpath[pathlen] = '/';
pathlen++;
if (opt_verbose) {
print_node('d', inode, path);
}
if (opt_extract) {
mkdir(path, inode->mode);
change_file_status(path, inode);
}
while (count > 0) {
struct cramfs_inode *child = iget(offset);
int size;
int newlen = child->namelen << 2;
size = sizeof(struct cramfs_inode) + newlen;
count -= size;
offset += sizeof(struct cramfs_inode);
memcpy(newpath + pathlen, romfs_read(offset), newlen);
newpath[pathlen + newlen] = 0;
if ((pathlen + newlen) - strlen(newpath) > 3) {
fprintf(stderr, "%s: invalid cramfs--bad path length\n", filename);
exit(4);
}
expand_fs(strlen(newpath), newpath, child);
offset += newlen;
if (offset > end_inode) {
end_inode = offset;
}
}
return;
}
if (S_ISREG(inode->mode)) {
int fd = 0;
unsigned long offset = inode->offset << 2;
if (offset > 0 && offset < start_data) {
start_data = offset;
}
if (opt_verbose) {
print_node('f', inode, path);
}
if (opt_extract) {
fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, inode->mode);
}
if (inode->size) {
do_uncompress(fd, offset, inode->size);
}
if (opt_extract) {
close(fd);
change_file_status(path, inode);
}
return;
}
if (S_ISLNK(inode->mode)) {
unsigned long offset = inode->offset << 2;
if (offset < start_data) {
start_data = offset;
}
do_symlink(path, inode);
return;
}
else {
do_special_inode(path, inode);
return;
}
}
#endif /* INCLUDE_FS_TESTS */
int main(int argc, char **argv)
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{
void *buf;
size_t length;
struct stat st;
u32 crc_old, crc_new;
#ifdef INCLUDE_FS_TESTS
struct cramfs_inode *root;
#endif /* INCLUDE_FS_TESTS */
int c; /* for getopt */
int start = 0;
if (argc)
progname = argv[0];
/* command line options */
while ((c = getopt(argc, argv, "hx:v")) != EOF) {
switch (c) {
case 'h':
usage(0);
case 'x':
#ifdef INCLUDE_FS_TESTS
opt_extract = 1;
extract_dir = malloc(strlen(optarg) + 1);
strcpy(extract_dir, optarg);
break;
#else /* not INCLUDE_FS_TESTS */
fprintf(stderr, "%s: compiled without -x support\n",
progname);
exit(16);
#endif /* not INCLUDE_FS_TESTS */
case 'v':
opt_verbose++;
break;
}
}
if ((argc - optind) != 1)
usage(16);
filename = argv[optind];
/* find the physical size of the file or block device */
if (lstat(filename, &st) < 0) {
perror(filename);
exit(8);
}
fd = open(filename, O_RDONLY);
if (fd < 0) {
perror(filename);
exit(8);
}
if (S_ISBLK(st.st_mode)) {
if (ioctl(fd, BLKGETSIZE, &length) < 0) {
fprintf(stderr, "%s: warning--unable to determine filesystem size \n", filename);
exit(4);
}
length = length * 512;
}
else if (S_ISREG(st.st_mode)) {
length = st.st_size;
}
else {
fprintf(stderr, "%s is not a block device or file\n", filename);
exit(8);
}
if (length < sizeof(struct cramfs_super)) {
fprintf(stderr, "%s: invalid cramfs--file length too short\n", filename);
exit(4);
}
if (S_ISBLK(st.st_mode)) {
/* nasty because mmap of block devices fails */
buf = mmap(NULL, length, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
read(fd, buf, length);
}
else {
/* nice and easy */
buf = mmap(NULL, length, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
}
/* XXX - this could be cleaner... */
if (((struct cramfs_super *) buf)->magic == CRAMFS_MAGIC) {
start = 0;
super = (struct cramfs_super *) buf;
}
else if (length >= (PAD_SIZE + sizeof(struct cramfs_super)) &&
((((struct cramfs_super *) (buf + PAD_SIZE))->magic == CRAMFS_MAGIC)))
{
start = PAD_SIZE;
super = (struct cramfs_super *) (buf + PAD_SIZE);
}
else {
fprintf(stderr, "%s: invalid cramfs--wrong magic\n", filename);
exit(4);
}
if (super->flags & CRAMFS_FLAG_FSID_VERSION_2) {
/* length test */
if (length < super->size) {
fprintf(stderr, "%s: invalid cramfs--file length too short\n", filename);
exit(4);
}
else if (length > super->size) {
fprintf(stderr, "%s: warning--file length too long, padded image?\n", filename);
}
/* CRC test */
crc_old = super->fsid.crc;
super->fsid.crc = crc32(0L, Z_NULL, 0);
crc_new = crc32(0L, Z_NULL, 0);
crc_new = crc32(crc_new, (unsigned char *) buf+start, super->size - start);
if (crc_new != crc_old) {
fprintf(stderr, "%s: invalid cramfs--crc error\n", filename);
exit(4);
}
}
else {
fprintf(stderr, "%s: warning--old cramfs image, no CRC\n",
filename);
}
#ifdef INCLUDE_FS_TESTS
super = (struct cramfs_super *) malloc(sizeof(struct cramfs_super));
if (((struct cramfs_super *) buf)->magic == CRAMFS_MAGIC) {
memcpy(super, buf, sizeof(struct cramfs_super));
}
else if (length >= (PAD_SIZE + sizeof(struct cramfs_super)) &&
((((struct cramfs_super *) (buf + PAD_SIZE))->magic == CRAMFS_MAGIC)))
{
memcpy(super, (buf + PAD_SIZE), sizeof(struct cramfs_super));
}
munmap(buf, length);
/* file format test, uses fake "blocked" accesses */
root = read_super();
umask(0);
euid = geteuid();
if (!root) {
fprintf(stderr, "%s: invalid cramfs--bad superblock\n",
filename);
exit(4);
}
stream.next_in = NULL;
stream.avail_in = 0;
inflateInit(&stream);
if (!extract_dir) {
extract_dir = "root";
}
expand_fs(strlen(extract_dir), extract_dir, root);
inflateEnd(&stream);
if (start_data != 1 << 28 && end_inode != start_data) {
fprintf(stderr, "%s: invalid cramfs--directory data end (%ld) != file data start (%ld)\n", filename, end_inode, start_data);
exit(4);
}
if (super->flags & CRAMFS_FLAG_FSID_VERSION_2) {
if (end_data > super->size) {
fprintf(stderr, "%s: invalid cramfs--invalid file data offset\n", filename);
exit(4);
}
}
#endif /* INCLUDE_FS_TESTS */
exit(0);
}