xref: /netbsd-src/sys/kern/subr_kobj_vfs.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
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 
77 static void
78 kobj_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  */
90 static int
91 kobj_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  */
133 int
134 kobj_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 
168 int
169 kobj_load_vfs(kobj_t *kop, const char *path, const bool nochroot)
170 {
171 
172 	return ENOSYS;
173 }
174 
175 #endif
176