subr_kobj_vfs.c revision 1.3
1/*	$NetBSD: subr_kobj_vfs.c,v 1.3 2010/06/24 13:03:11 hannken Exp $	*/
2
3/*-
4 * Copyright (c) 2008 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software developed for The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*-
33 * Copyright (c) 1998-2000 Doug Rabson
34 * Copyright (c) 2004 Peter Wemm
35 * All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 *    notice, this list of conditions and the following disclaimer in the
44 *    documentation and/or other materials provided with the distribution.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 * SUCH DAMAGE.
57 */
58
59/*
60 * Kernel loader vfs routines.
61 */
62
63#include <sys/kobj_impl.h>
64#include "opt_modular.h"
65
66#ifdef MODULAR
67
68#include <sys/param.h>
69#include <sys/fcntl.h>
70#include <sys/module.h>
71#include <sys/namei.h>
72#include <sys/vnode.h>
73
74#include <sys/cdefs.h>
75__KERNEL_RCSID(0, "$NetBSD: subr_kobj_vfs.c,v 1.3 2010/06/24 13:03:11 hannken Exp $");
76
77static void
78kobj_close_vfs(kobj_t ko)
79{
80
81	VOP_UNLOCK(ko->ko_source);
82	vn_close(ko->ko_source, FREAD, kauth_cred_get());
83}
84
85/*
86 * kobj_read:
87 *
88 *	Utility function: read from the object.
89 */
90static int
91kobj_read_vfs(kobj_t ko, void **basep, size_t size, off_t off,
92	bool allocate)
93{
94	size_t resid;
95	void *base;
96	int error;
97
98	KASSERT(ko->ko_source != NULL);
99
100	if (allocate) {
101		base = kmem_alloc(size, KM_SLEEP);
102	} else {
103		base = *basep;
104		KASSERT((uintptr_t)base >= (uintptr_t)ko->ko_address);
105		KASSERT((uintptr_t)base + size <=
106		    (uintptr_t)ko->ko_address + ko->ko_size);
107	}
108
109	error = vn_rdwr(UIO_READ, ko->ko_source, base, size, off,
110	    UIO_SYSSPACE, IO_NODELOCKED, curlwp->l_cred, &resid,
111	    curlwp);
112
113	if (error == 0 && resid != 0) {
114		error = EINVAL;
115	}
116
117	if (allocate && error != 0) {
118		kmem_free(base, size);
119		base = NULL;
120	}
121
122	if (allocate)
123		*basep = base;
124
125	return error;
126}
127
128/*
129 * kobj_load_vfs:
130 *
131 *	Load an object located in the file system.
132 */
133int
134kobj_load_vfs(kobj_t *kop, const char *path, const bool nochroot)
135{
136	struct nameidata nd;
137	kauth_cred_t cred;
138	int error;
139	kobj_t ko;
140
141	cred = kauth_cred_get();
142
143	ko = kmem_zalloc(sizeof(*ko), KM_SLEEP);
144	if (ko == NULL) {
145		return ENOMEM;
146	}
147
148	NDINIT(&nd, LOOKUP, FOLLOW | (nochroot ? NOCHROOT : 0),
149	    UIO_SYSSPACE, path);
150	error = vn_open(&nd, FREAD, 0);
151
152 	if (error != 0) {
153	 	kmem_free(ko, sizeof(*ko));
154	 	return error;
155	}
156
157	ko->ko_type = KT_VNODE;
158	ko->ko_source = nd.ni_vp;
159	ko->ko_read = kobj_read_vfs;
160	ko->ko_close = kobj_close_vfs;
161
162	*kop = ko;
163	return kobj_load(ko);
164}
165
166#else /* MODULAR */
167
168int
169kobj_load_vfs(kobj_t *kop, const char *path, const bool nochroot)
170{
171
172	return ENOSYS;
173}
174
175#endif
176