freebsd-dev/lib/libstand/cd9660.c
Nathan Whitehorn 149ae064ad Fix loader's ability to read the 10.1 release PowerPC ISOs. There appears to
be some kind of problem with the version of makefs used for these disks.
There may be a better way to handle this problem, so I've set the MFC
timer for a fairly long time period.

MFC after:	2 weeks
2014-12-30 16:55:53 +00:00

594 lines
15 KiB
C

/* $NetBSD: cd9660.c,v 1.5 1997/06/26 19:11:33 drochner Exp $ */
/*
* Copyright (C) 1996 Wolfgang Solfrank.
* Copyright (C) 1996 TooLs GmbH.
* 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.
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Stand-alone ISO9660 file reading package.
*
* Note: This doesn't support Rock Ridge extensions, extended attributes,
* blocksizes other than 2048 bytes, multi-extent files, etc.
*/
#include <sys/param.h>
#include <string.h>
#include <sys/dirent.h>
#include <isofs/cd9660/iso.h>
#include <isofs/cd9660/cd9660_rrip.h>
#include "stand.h"
#define SUSP_CONTINUATION "CE"
#define SUSP_PRESENT "SP"
#define SUSP_STOP "ST"
#define SUSP_EXTREF "ER"
#define RRIP_NAME "NM"
typedef struct {
ISO_SUSP_HEADER h;
u_char signature [ISODCL ( 5, 6)];
u_char len_skp [ISODCL ( 7, 7)]; /* 711 */
} ISO_SUSP_PRESENT;
static int buf_read_file(struct open_file *f, char **buf_p,
size_t *size_p);
static int cd9660_open(const char *path, struct open_file *f);
static int cd9660_close(struct open_file *f);
static int cd9660_read(struct open_file *f, void *buf, size_t size,
size_t *resid);
static int cd9660_write(struct open_file *f, void *buf, size_t size,
size_t *resid);
static off_t cd9660_seek(struct open_file *f, off_t offset, int where);
static int cd9660_stat(struct open_file *f, struct stat *sb);
static int cd9660_readdir(struct open_file *f, struct dirent *d);
static int dirmatch(struct open_file *f, const char *path,
struct iso_directory_record *dp, int use_rrip, int lenskip);
static int rrip_check(struct open_file *f, struct iso_directory_record *dp,
int *lenskip);
static char *rrip_lookup_name(struct open_file *f,
struct iso_directory_record *dp, int lenskip, size_t *len);
static ISO_SUSP_HEADER *susp_lookup_record(struct open_file *f,
const char *identifier, struct iso_directory_record *dp,
int lenskip);
struct fs_ops cd9660_fsops = {
"cd9660",
cd9660_open,
cd9660_close,
cd9660_read,
cd9660_write,
cd9660_seek,
cd9660_stat,
cd9660_readdir
};
#define F_ISDIR 0x0001 /* Directory */
#define F_ROOTDIR 0x0002 /* Root directory */
#define F_RR 0x0004 /* Rock Ridge on this volume */
struct file {
int f_flags; /* file flags */
off_t f_off; /* Current offset within file */
daddr_t f_bno; /* Starting block number */
off_t f_size; /* Size of file */
daddr_t f_buf_blkno; /* block number of data block */
char *f_buf; /* buffer for data block */
int f_susp_skip; /* len_skip for SUSP records */
};
struct ptable_ent {
char namlen [ISODCL( 1, 1)]; /* 711 */
char extlen [ISODCL( 2, 2)]; /* 711 */
char block [ISODCL( 3, 6)]; /* 732 */
char parent [ISODCL( 7, 8)]; /* 722 */
char name [1];
};
#define PTFIXSZ 8
#define PTSIZE(pp) roundup(PTFIXSZ + isonum_711((pp)->namlen), 2)
#define cdb2devb(bno) ((bno) * ISO_DEFAULT_BLOCK_SIZE / DEV_BSIZE)
static ISO_SUSP_HEADER *
susp_lookup_record(struct open_file *f, const char *identifier,
struct iso_directory_record *dp, int lenskip)
{
static char susp_buffer[ISO_DEFAULT_BLOCK_SIZE];
ISO_SUSP_HEADER *sh;
ISO_RRIP_CONT *shc;
char *p, *end;
int error;
size_t read;
p = dp->name + isonum_711(dp->name_len) + lenskip;
/* Names of even length have a padding byte after the name. */
if ((isonum_711(dp->name_len) & 1) == 0)
p++;
end = (char *)dp + isonum_711(dp->length);
while (p + 3 < end) {
sh = (ISO_SUSP_HEADER *)p;
if (bcmp(sh->type, identifier, 2) == 0)
return (sh);
if (bcmp(sh->type, SUSP_STOP, 2) == 0)
return (NULL);
if (bcmp(sh->type, SUSP_CONTINUATION, 2) == 0) {
shc = (ISO_RRIP_CONT *)sh;
error = f->f_dev->dv_strategy(f->f_devdata, F_READ,
cdb2devb(isonum_733(shc->location)),
ISO_DEFAULT_BLOCK_SIZE, susp_buffer, &read);
/* Bail if it fails. */
if (error != 0 || read != ISO_DEFAULT_BLOCK_SIZE)
return (NULL);
p = susp_buffer + isonum_733(shc->offset);
end = p + isonum_733(shc->length);
} else {
/* Ignore this record and skip to the next. */
p += isonum_711(sh->length);
/* Avoid infinite loops with corrupted file systems */
if (isonum_711(sh->length) == 0)
return (NULL);
}
}
return (NULL);
}
static char *
rrip_lookup_name(struct open_file *f, struct iso_directory_record *dp,
int lenskip, size_t *len)
{
ISO_RRIP_ALTNAME *p;
if (len == NULL)
return (NULL);
p = (ISO_RRIP_ALTNAME *)susp_lookup_record(f, RRIP_NAME, dp, lenskip);
if (p == NULL)
return (NULL);
switch (*p->flags) {
case ISO_SUSP_CFLAG_CURRENT:
*len = 1;
return (".");
case ISO_SUSP_CFLAG_PARENT:
*len = 2;
return ("..");
case 0:
*len = isonum_711(p->h.length) - 5;
return ((char *)p + 5);
default:
/*
* We don't handle hostnames or continued names as they are
* too hard, so just bail and use the default name.
*/
return (NULL);
}
}
static int
rrip_check(struct open_file *f, struct iso_directory_record *dp, int *lenskip)
{
ISO_SUSP_PRESENT *sp;
ISO_RRIP_EXTREF *er;
char *p;
/* First, see if we can find a SP field. */
p = dp->name + isonum_711(dp->name_len);
if (p > (char *)dp + isonum_711(dp->length))
return (0);
sp = (ISO_SUSP_PRESENT *)p;
if (bcmp(sp->h.type, SUSP_PRESENT, 2) != 0)
return (0);
if (isonum_711(sp->h.length) != sizeof(ISO_SUSP_PRESENT))
return (0);
if (sp->signature[0] != 0xbe || sp->signature[1] != 0xef)
return (0);
*lenskip = isonum_711(sp->len_skp);
/*
* Now look for an ER field. If RRIP is present, then there must
* be at least one of these. It would be more pedantic to walk
* through the list of fields looking for a Rock Ridge ER field.
*/
er = (ISO_RRIP_EXTREF *)susp_lookup_record(f, SUSP_EXTREF, dp, 0);
if (er == NULL)
return (0);
return (1);
}
static int
dirmatch(struct open_file *f, const char *path, struct iso_directory_record *dp,
int use_rrip, int lenskip)
{
size_t len;
char *cp;
int i, icase;
if (use_rrip)
cp = rrip_lookup_name(f, dp, lenskip, &len);
else
cp = NULL;
if (cp == NULL) {
len = isonum_711(dp->name_len);
cp = dp->name;
icase = 1;
} else
icase = 0;
for (i = len; --i >= 0; path++, cp++) {
if (!*path || *path == '/')
break;
if (*path == *cp)
continue;
if (!icase && toupper(*path) == *cp)
continue;
return 0;
}
if (*path && *path != '/')
return 0;
/*
* Allow stripping of trailing dots and the version number.
* Note that this will find the first instead of the last version
* of a file.
*/
if (i >= 0 && (*cp == ';' || *cp == '.')) {
/* This is to prevent matching of numeric extensions */
if (*cp == '.' && cp[1] != ';')
return 0;
while (--i >= 0)
if (*++cp != ';' && (*cp < '0' || *cp > '9'))
return 0;
}
return 1;
}
static int
cd9660_open(const char *path, struct open_file *f)
{
struct file *fp = 0;
void *buf;
struct iso_primary_descriptor *vd;
size_t buf_size, read, dsize, off;
daddr_t bno, boff;
struct iso_directory_record rec;
struct iso_directory_record *dp = 0;
int rc, first, use_rrip, lenskip;
/* First find the volume descriptor */
buf = malloc(buf_size = ISO_DEFAULT_BLOCK_SIZE);
vd = buf;
for (bno = 16;; bno++) {
twiddle(1);
rc = f->f_dev->dv_strategy(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, buf, &read);
if (rc)
goto out;
if (read != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
rc = EINVAL;
if (bcmp(vd->id, ISO_STANDARD_ID, sizeof vd->id) != 0)
goto out;
if (isonum_711(vd->type) == ISO_VD_END)
goto out;
if (isonum_711(vd->type) == ISO_VD_PRIMARY)
break;
}
if (isonum_723(vd->logical_block_size) != ISO_DEFAULT_BLOCK_SIZE)
goto out;
rec = *(struct iso_directory_record *) vd->root_directory_record;
if (*path == '/') path++; /* eat leading '/' */
first = 1;
use_rrip = 0;
while (*path) {
bno = isonum_733(rec.extent) + isonum_711(rec.ext_attr_length);
dsize = isonum_733(rec.size);
off = 0;
boff = 0;
while (off < dsize) {
if ((off % ISO_DEFAULT_BLOCK_SIZE) == 0) {
twiddle(1);
rc = f->f_dev->dv_strategy
(f->f_devdata, F_READ,
cdb2devb(bno + boff),
ISO_DEFAULT_BLOCK_SIZE,
buf, &read);
if (rc)
goto out;
if (read != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
boff++;
dp = (struct iso_directory_record *) buf;
}
if (isonum_711(dp->length) == 0) {
/* skip to next block, if any */
off = boff * ISO_DEFAULT_BLOCK_SIZE;
continue;
}
/* See if RRIP is in use. */
if (first)
use_rrip = rrip_check(f, dp, &lenskip);
if (dirmatch(f, path, dp, use_rrip,
first ? 0 : lenskip)) {
first = 0;
break;
} else
first = 0;
dp = (struct iso_directory_record *)
((char *) dp + isonum_711(dp->length));
off += isonum_711(dp->length);
}
if (off >= dsize) {
rc = ENOENT;
goto out;
}
rec = *dp;
while (*path && *path != '/') /* look for next component */
path++;
if (*path) path++; /* skip '/' */
}
/* allocate file system specific data structure */
fp = malloc(sizeof(struct file));
bzero(fp, sizeof(struct file));
f->f_fsdata = (void *)fp;
if ((isonum_711(rec.flags) & 2) != 0) {
fp->f_flags = F_ISDIR;
}
if (first) {
fp->f_flags |= F_ROOTDIR;
/* Check for Rock Ridge since we didn't in the loop above. */
bno = isonum_733(rec.extent) + isonum_711(rec.ext_attr_length);
twiddle(1);
rc = f->f_dev->dv_strategy(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, buf, &read);
if (rc)
goto out;
if (read != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
dp = (struct iso_directory_record *)buf;
use_rrip = rrip_check(f, dp, &lenskip);
}
if (use_rrip) {
fp->f_flags |= F_RR;
fp->f_susp_skip = lenskip;
}
fp->f_off = 0;
fp->f_bno = isonum_733(rec.extent) + isonum_711(rec.ext_attr_length);
fp->f_size = isonum_733(rec.size);
free(buf);
return 0;
out:
if (fp)
free(fp);
free(buf);
return rc;
}
static int
cd9660_close(struct open_file *f)
{
struct file *fp = (struct file *)f->f_fsdata;
f->f_fsdata = 0;
free(fp);
return 0;
}
static int
buf_read_file(struct open_file *f, char **buf_p, size_t *size_p)
{
struct file *fp = (struct file *)f->f_fsdata;
daddr_t blkno, blkoff;
int rc = 0;
size_t read;
blkno = fp->f_off / ISO_DEFAULT_BLOCK_SIZE + fp->f_bno;
blkoff = fp->f_off % ISO_DEFAULT_BLOCK_SIZE;
if (blkno != fp->f_buf_blkno) {
if (fp->f_buf == (char *)0)
fp->f_buf = malloc(ISO_DEFAULT_BLOCK_SIZE);
twiddle(16);
rc = f->f_dev->dv_strategy(f->f_devdata, F_READ,
cdb2devb(blkno), ISO_DEFAULT_BLOCK_SIZE, fp->f_buf, &read);
if (rc)
return (rc);
if (read != ISO_DEFAULT_BLOCK_SIZE)
return (EIO);
fp->f_buf_blkno = blkno;
}
*buf_p = fp->f_buf + blkoff;
*size_p = ISO_DEFAULT_BLOCK_SIZE - blkoff;
if (*size_p > fp->f_size - fp->f_off)
*size_p = fp->f_size - fp->f_off;
return (rc);
}
static int
cd9660_read(struct open_file *f, void *start, size_t size, size_t *resid)
{
struct file *fp = (struct file *)f->f_fsdata;
char *buf, *addr;
size_t buf_size, csize;
int rc = 0;
addr = start;
while (size) {
if (fp->f_off < 0 || fp->f_off >= fp->f_size)
break;
rc = buf_read_file(f, &buf, &buf_size);
if (rc)
break;
csize = size > buf_size ? buf_size : size;
bcopy(buf, addr, csize);
fp->f_off += csize;
addr += csize;
size -= csize;
}
if (resid)
*resid = size;
return (rc);
}
static int
cd9660_readdir(struct open_file *f, struct dirent *d)
{
struct file *fp = (struct file *)f->f_fsdata;
struct iso_directory_record *ep;
size_t buf_size, reclen, namelen;
int error = 0;
int lenskip;
char *buf, *name;
again:
if (fp->f_off >= fp->f_size)
return (ENOENT);
error = buf_read_file(f, &buf, &buf_size);
if (error)
return (error);
ep = (struct iso_directory_record *)buf;
if (isonum_711(ep->length) == 0) {
daddr_t blkno;
/* skip to next block, if any */
blkno = fp->f_off / ISO_DEFAULT_BLOCK_SIZE;
fp->f_off = (blkno + 1) * ISO_DEFAULT_BLOCK_SIZE;
goto again;
}
if (fp->f_flags & F_RR) {
if (fp->f_flags & F_ROOTDIR && fp->f_off == 0)
lenskip = 0;
else
lenskip = fp->f_susp_skip;
name = rrip_lookup_name(f, ep, lenskip, &namelen);
} else
name = NULL;
if (name == NULL) {
namelen = isonum_711(ep->name_len);
name = ep->name;
if (namelen == 1) {
if (ep->name[0] == 0)
name = ".";
else if (ep->name[0] == 1) {
namelen = 2;
name = "..";
}
}
}
reclen = sizeof(struct dirent) - (MAXNAMLEN+1) + namelen + 1;
reclen = (reclen + 3) & ~3;
d->d_fileno = isonum_733(ep->extent);
d->d_reclen = reclen;
if (isonum_711(ep->flags) & 2)
d->d_type = DT_DIR;
else
d->d_type = DT_REG;
d->d_namlen = namelen;
bcopy(name, d->d_name, d->d_namlen);
d->d_name[d->d_namlen] = 0;
fp->f_off += isonum_711(ep->length);
return (0);
}
static int
cd9660_write(struct open_file *f __unused, void *start __unused, size_t size __unused, size_t *resid __unused)
{
return EROFS;
}
static off_t
cd9660_seek(struct open_file *f, off_t offset, int where)
{
struct file *fp = (struct file *)f->f_fsdata;
switch (where) {
case SEEK_SET:
fp->f_off = offset;
break;
case SEEK_CUR:
fp->f_off += offset;
break;
case SEEK_END:
fp->f_off = fp->f_size - offset;
break;
default:
return -1;
}
return fp->f_off;
}
static int
cd9660_stat(struct open_file *f, struct stat *sb)
{
struct file *fp = (struct file *)f->f_fsdata;
/* only important stuff */
sb->st_mode = S_IRUSR | S_IRGRP | S_IROTH;
if (fp->f_flags & F_ISDIR)
sb->st_mode |= S_IFDIR;
else
sb->st_mode |= S_IFREG;
sb->st_uid = sb->st_gid = 0;
sb->st_size = fp->f_size;
return 0;
}