xref: /netbsd-src/sys/kern/kern_module_vfs.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: kern_module_vfs.c,v 1.7 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  * Kernel module file system interaction.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: kern_module_vfs.c,v 1.7 2010/06/24 13:03:11 hannken Exp $");
38 
39 #define _MODULE_INTERNAL
40 #include <sys/param.h>
41 #include <sys/fcntl.h>
42 #include <sys/kmem.h>
43 #include <sys/kobj.h>
44 #include <sys/module.h>
45 #include <sys/namei.h>
46 #include <sys/pool.h>
47 #include <sys/stat.h>
48 #include <sys/vnode.h>
49 
50 #include <prop/proplib.h>
51 
52 static int	module_load_plist_vfs(const char *, const bool,
53 				      prop_dictionary_t *);
54 
55 void
56 module_load_vfs_init(void)
57 {
58 	module_load_vfs_vec = module_load_vfs;
59 }
60 
61 int
62 module_load_vfs(const char *name, int flags, bool autoload,
63 	module_t *mod, prop_dictionary_t *filedictp)
64 {
65 	char *path;
66 	bool nochroot;
67 	int error;
68 
69 	nochroot = false;
70 	error = 0;
71 	path = NULL;
72 	if (filedictp)
73 		*filedictp = NULL;
74 	path = PNBUF_GET();
75 
76 	if (!autoload) {
77 		nochroot = false;
78 		snprintf(path, MAXPATHLEN, "%s", name);
79 		error = kobj_load_vfs(&mod->mod_kobj, path, nochroot);
80 	}
81 	if (autoload || (error == ENOENT)) {
82 		nochroot = true;
83 		snprintf(path, MAXPATHLEN, "%s/%s/%s.kmod",
84 		    module_base, name, name);
85 		error = kobj_load_vfs(&mod->mod_kobj, path, nochroot);
86 	}
87 	if (error != 0) {
88 		PNBUF_PUT(path);
89 		if (autoload) {
90 			module_print("Cannot load kernel object `%s'"
91 			    " error=%d", name, error);
92 		} else {
93 			module_error("Cannot load kernel object `%s'"
94 			    " error=%d", name, error);
95 		}
96 		return error;
97 	}
98 
99 	/*
100 	 * Load and process <module>.prop if it exists.
101 	 */
102 	if ((flags & MODCTL_NO_PROP) == 0 && filedictp) {
103 		error = module_load_plist_vfs(path, nochroot, filedictp);
104 		if (error != 0) {
105 			module_print("plist load returned error %d for `%s'",
106 			    error, path);
107 			if (error != ENOENT)
108 				goto fail;
109 		}
110 	}
111 
112 	PNBUF_PUT(path);
113 	return 0;
114 
115  fail:
116 	kobj_unload(mod->mod_kobj);
117 	PNBUF_PUT(path);
118 	return error;
119 }
120 
121 /*
122  * module_load_plist_vfs:
123  *
124  *	Load a plist located in the file system into memory.
125  */
126 static int
127 module_load_plist_vfs(const char *modpath, const bool nochroot,
128 		       prop_dictionary_t *filedictp)
129 {
130 	struct nameidata nd;
131 	struct stat sb;
132 	void *base;
133 	char *proppath;
134 	const size_t plistsize = 8192;
135 	size_t resid;
136 	int error, pathlen;
137 
138 	KASSERT(filedictp != NULL);
139 	base = NULL;
140 
141 	proppath = PNBUF_GET();
142 	strcpy(proppath, modpath);
143 	pathlen = strlen(proppath);
144 	if ((pathlen >= 5) && (strcmp(&proppath[pathlen - 5], ".kmod") == 0)) {
145 		strcpy(&proppath[pathlen - 5], ".prop");
146 	} else if (pathlen < MAXPATHLEN - 5) {
147 			strcat(proppath, ".prop");
148 	} else {
149 		error = ENOENT;
150 		goto out1;
151 	}
152 
153 	NDINIT(&nd, LOOKUP, FOLLOW | (nochroot ? NOCHROOT : 0),
154 	    UIO_SYSSPACE, proppath);
155 
156 	error = vn_open(&nd, FREAD, 0);
157  	if (error != 0) {
158 	 	goto out1;
159 	}
160 
161 	error = vn_stat(nd.ni_vp, &sb);
162 	if (error != 0) {
163 		goto out;
164 	}
165 	if (sb.st_size >= (plistsize - 1)) {	/* leave space for term \0 */
166 		error = EFBIG;
167 		goto out;
168 	}
169 
170 	base = kmem_alloc(plistsize, KM_SLEEP);
171 	if (base == NULL) {
172 		error = ENOMEM;
173 		goto out;
174 	}
175 
176 	error = vn_rdwr(UIO_READ, nd.ni_vp, base, sb.st_size, 0,
177 	    UIO_SYSSPACE, IO_NODELOCKED, curlwp->l_cred, &resid, curlwp);
178 	*((uint8_t *)base + sb.st_size) = '\0';
179 	if (error == 0 && resid != 0) {
180 		error = EFBIG;
181 	}
182 	if (error != 0) {
183 		kmem_free(base, plistsize);
184 		base = NULL;
185 		goto out;
186 	}
187 
188 	*filedictp = prop_dictionary_internalize(base);
189 	if (*filedictp == NULL) {
190 		error = EINVAL;
191 	}
192 	kmem_free(base, plistsize);
193 	base = NULL;
194 	KASSERT(error == 0);
195 
196 out:
197 	VOP_UNLOCK(nd.ni_vp);
198 	vn_close(nd.ni_vp, FREAD, kauth_cred_get());
199 
200 out1:
201 	PNBUF_PUT(proppath);
202 	return error;
203 }
204