/*
* Read POSIX.1e ACL from an EA. Return error if its not found
* or if any other error has occurred.
*/
static int
ufs_get_oldacl(acl_type_t type, struct oldacl *old, struct vnode *vp,
struct thread *td)
{
int error, len;
struct inode *ip = VTOI(vp);
len = sizeof(*old);
switch (type) {
case ACL_TYPE_ACCESS:
error = vn_extattr_get(vp, IO_NODELOCKED,
POSIX1E_ACL_ACCESS_EXTATTR_NAMESPACE,
POSIX1E_ACL_ACCESS_EXTATTR_NAME, &len, (char *) old,
td);
break;
case ACL_TYPE_DEFAULT:
if (vp->v_type != VDIR)
return (EINVAL);
error = vn_extattr_get(vp, IO_NODELOCKED,
POSIX1E_ACL_DEFAULT_EXTATTR_NAMESPACE,
POSIX1E_ACL_DEFAULT_EXTATTR_NAME, &len, (char *) old,
td);
break;
default:
return (EINVAL);
}
if (error != 0)
return (error);
if (len != sizeof(*old)) {
/*
* A short (or long) read, meaning that for some reason
* the ACL is corrupted. Return EPERM since the object
* DAC protections are unsafe.
*/
printf("ufs_get_oldacl(): Loaded invalid ACL "
"(len = %d), inumber %ju on %s\n", len,
(uintmax_t)ip->i_number, ip->i_fs->fs_fsmnt);
return (EPERM);
}
return (0);
}
/*
* Retrieve NFSv4 ACL, skipping access checks. Must be used in UFS code
* instead of VOP_GETACL() when we don't want to be restricted by the user
* not having ACL_READ_ACL permission, e.g. when calculating inherited ACL
* or in ufs_vnops.c:ufs_accessx().
*/
int
ufs_getacl_nfs4_internal(struct vnode *vp, struct acl *aclp, struct thread *td)
{
int error, len;
struct inode *ip = VTOI(vp);
len = sizeof(*aclp);
bzero(aclp, len);
error = vn_extattr_get(vp, IO_NODELOCKED,
NFS4_ACL_EXTATTR_NAMESPACE, NFS4_ACL_EXTATTR_NAME,
&len, (char *) aclp, td);
aclp->acl_maxcnt = ACL_MAX_ENTRIES;
if (error == ENOATTR) {
/*
* Legitimately no ACL set on object, purely
* emulate it through the inode.
*/
acl_nfs4_sync_acl_from_mode(aclp, ip->i_mode, ip->i_uid);
return (0);
}
if (error)
return (error);
if (len != sizeof(*aclp)) {
/*
* A short (or long) read, meaning that for
* some reason the ACL is corrupted. Return
* EPERM since the object DAC protections
* are unsafe.
*/
printf("ufs_getacl_nfs4(): Loaded invalid ACL ("
"%d bytes), inumber %ju on %s\n", len,
(uintmax_t)ip->i_number, ip->i_fs->fs_fsmnt);
return (EPERM);
}
error = acl_nfs4_check(aclp, vp->v_type == VDIR);
if (error) {
printf("ufs_getacl_nfs4(): Loaded invalid ACL "
"(failed acl_nfs4_check), inumber %ju on %s\n",
(uintmax_t)ip->i_number, ip->i_fs->fs_fsmnt);
return (EPERM);
}
return (0);
}
static int
verify_file(struct ucred *cred, struct vnode *vp)
{
char buffer[256];
char hash[SHA256_DIGEST_LENGTH > uECC_BYTES ? SHA256_DIGEST_LENGTH : uECC_BYTES];
char signature[2*uECC_BYTES];
int error, len;
ssize_t resid;
off_t i, size;
SHA256_CTX ctx;
struct stat stat;
i = 0;
error = vn_stat(vp, &stat, cred, NOCRED, curthread);
size = stat.st_size;
if (error)
return (EPERM);
len = sizeof(signature);
error = vn_extattr_get(vp, IO_NODELOCKED, EXTATTR_NAMESPACE_SYSTEM,
"signature", &len, signature, curthread);
if (error)
return (EPERM);
#ifdef DEBUG
printf("Signature: ");
print_hex(signature, sizeof(signature));
#endif
SHA256_Init(&ctx);
while(i < size && !error) {
len = size - i > sizeof(buffer) ? sizeof(buffer) : size - i;
error = vn_rdwr(UIO_READ, vp, buffer, len, i,
UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED,
&resid, curthread);
SHA256_Update(&ctx, buffer, len);
i += len;
}
if (error)
return (EPERM);
SHA256_Final(hash, &ctx);
#ifdef DEBUG
printf("Hash: ");
print_hex(hash, sizeof(hash));
#endif
if (!uECC_verify(pubkey, hash, signature))
return (EPERM);
return (0);
}
