/*
* Verify that a directory entry is valid.
* This is a superset of the checks made in the kernel.
*/
int
dircheck(struct inodesc *idesc, LFS_DIRHEADER *dp)
{
int size;
const char *cp;
u_char namlen, type;
int spaceleft;
spaceleft = LFS_DIRBLKSIZ - (idesc->id_loc % LFS_DIRBLKSIZ);
if (lfs_dir_getino(fs, dp) >= maxino ||
lfs_dir_getreclen(fs, dp) == 0 ||
lfs_dir_getreclen(fs, dp) > spaceleft ||
(lfs_dir_getreclen(fs, dp) & 0x3) != 0) {
pwarn("ino too large, reclen=0, reclen>space, or reclen&3!=0\n");
pwarn("dp->d_ino = 0x%jx\tdp->d_reclen = 0x%x\n",
(uintmax_t)lfs_dir_getino(fs, dp),
lfs_dir_getreclen(fs, dp));
pwarn("maxino = %ju\tspaceleft = 0x%x\n",
(uintmax_t)maxino, spaceleft);
return (0);
}
if (lfs_dir_getino(fs, dp) == 0)
return (1);
size = LFS_DIRSIZ(fs, dp);
namlen = lfs_dir_getnamlen(fs, dp);
type = lfs_dir_gettype(fs, dp);
if (lfs_dir_getreclen(fs, dp) < size ||
idesc->id_filesize < size ||
/* namlen > MAXNAMLEN || */
type > 15) {
printf("reclen<size, filesize<size, namlen too large, or type>15\n");
return (0);
}
cp = lfs_dir_nameptr(fs, dp);
for (size = 0; size < namlen; size++)
if (*cp == '\0' || (*cp++ == '/')) {
printf("name contains NUL or /\n");
return (0);
}
if (*cp != '\0') {
printf("name size misstated\n");
return (0);
}
return (1);
}
/*
* Vnode op for reading directories.
*
* This routine handles converting from the on-disk directory format
* "struct lfs_direct" to the in-memory format "struct dirent" as well as
* byte swapping the entries if necessary.
*/
int
ulfs_readdir(void *v)
{
struct vop_readdir_args /* {
struct vnode *a_vp;
struct uio *a_uio;
kauth_cred_t a_cred;
int *a_eofflag;
off_t **a_cookies;
int *ncookies;
} */ *ap = v;
struct vnode *vp = ap->a_vp;
LFS_DIRHEADER *cdp, *ecdp;
struct dirent *ndp;
char *cdbuf, *ndbuf, *endp;
struct uio auio, *uio;
struct iovec aiov;
int error;
size_t count, ccount, rcount, cdbufsz, ndbufsz;
off_t off, *ccp;
off_t startoff;
size_t skipbytes;
struct ulfsmount *ump = VFSTOULFS(vp->v_mount);
struct lfs *fs = ump->um_lfs;
uio = ap->a_uio;
count = uio->uio_resid;
rcount = count - ((uio->uio_offset + count) & (fs->um_dirblksiz - 1));
if (rcount < LFS_DIRECTSIZ(fs, 0) || count < _DIRENT_MINSIZE(ndp))
return EINVAL;
startoff = uio->uio_offset & ~(fs->um_dirblksiz - 1);
skipbytes = uio->uio_offset - startoff;
rcount += skipbytes;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = startoff;
auio.uio_resid = rcount;
UIO_SETUP_SYSSPACE(&auio);
auio.uio_rw = UIO_READ;
cdbufsz = rcount;
cdbuf = kmem_alloc(cdbufsz, KM_SLEEP);
aiov.iov_base = cdbuf;
aiov.iov_len = rcount;
error = VOP_READ(vp, &auio, 0, ap->a_cred);
if (error != 0) {
kmem_free(cdbuf, cdbufsz);
return error;
}
rcount -= auio.uio_resid;
cdp = (LFS_DIRHEADER *)(void *)cdbuf;
ecdp = (LFS_DIRHEADER *)(void *)&cdbuf[rcount];
ndbufsz = count;
ndbuf = kmem_alloc(ndbufsz, KM_SLEEP);
ndp = (struct dirent *)(void *)ndbuf;
endp = &ndbuf[count];
off = uio->uio_offset;
if (ap->a_cookies) {
ccount = rcount / _DIRENT_RECLEN(ndp, 1);
ccp = *(ap->a_cookies) = malloc(ccount * sizeof(*ccp),
M_TEMP, M_WAITOK);
} else {
/* XXX: GCC */
ccount = 0;
ccp = NULL;
}
while (cdp < ecdp) {
if (skipbytes > 0) {
if (lfs_dir_getreclen(fs, cdp) <= skipbytes) {
skipbytes -= lfs_dir_getreclen(fs, cdp);
cdp = LFS_NEXTDIR(fs, cdp);
continue;
}
/*
* invalid cookie.
*/
error = EINVAL;
goto out;
}
if (lfs_dir_getreclen(fs, cdp) == 0) {
struct dirent *ondp = ndp;
ndp->d_reclen = _DIRENT_MINSIZE(ndp);
ndp = _DIRENT_NEXT(ndp);
ondp->d_reclen = 0;
cdp = ecdp;
break;
}
ndp->d_type = lfs_dir_gettype(fs, cdp);
ndp->d_namlen = lfs_dir_getnamlen(fs, cdp);
ndp->d_reclen = _DIRENT_RECLEN(ndp, ndp->d_namlen);
if ((char *)(void *)ndp + ndp->d_reclen +
_DIRENT_MINSIZE(ndp) > endp)
break;
ndp->d_fileno = lfs_dir_getino(fs, cdp);
(void)memcpy(ndp->d_name, lfs_dir_nameptr(fs, cdp),
ndp->d_namlen);
memset(&ndp->d_name[ndp->d_namlen], 0,
ndp->d_reclen - _DIRENT_NAMEOFF(ndp) - ndp->d_namlen);
off += lfs_dir_getreclen(fs, cdp);
if (ap->a_cookies) {
KASSERT(ccp - *(ap->a_cookies) < ccount);
*(ccp++) = off;
}
ndp = _DIRENT_NEXT(ndp);
cdp = LFS_NEXTDIR(fs, cdp);
}
count = ((char *)(void *)ndp - ndbuf);
error = uiomove(ndbuf, count, uio);
out:
if (ap->a_cookies) {
if (error) {
free(*(ap->a_cookies), M_TEMP);
*(ap->a_cookies) = NULL;
*(ap->a_ncookies) = 0;
} else {
*ap->a_ncookies = ccp - *(ap->a_cookies);
}
}
uio->uio_offset = off;
kmem_free(ndbuf, ndbufsz);
kmem_free(cdbuf, cdbufsz);
*ap->a_eofflag = VTOI(vp)->i_size <= uio->uio_offset;
return error;
}
