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      1 /*	$NetBSD: subr_kobj_vfs.c,v 1.12 2021/06/29 22:40:53 dholland 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 
     65 #ifdef _KERNEL_OPT
     66 #include "opt_modular.h"
     67 #endif
     68 
     69 #ifdef MODULAR
     70 
     71 #include <sys/param.h>
     72 #include <sys/fcntl.h>
     73 #include <sys/module.h>
     74 #include <sys/namei.h>
     75 #include <sys/vnode.h>
     76 
     77 #include <sys/cdefs.h>
     78 __KERNEL_RCSID(0, "$NetBSD: subr_kobj_vfs.c,v 1.12 2021/06/29 22:40:53 dholland Exp $");
     79 
     80 static void
     81 kobj_close_vfs(kobj_t ko)
     82 {
     83 
     84 	VOP_UNLOCK(ko->ko_source);
     85 	vn_close(ko->ko_source, FREAD, kauth_cred_get());
     86 }
     87 
     88 /*
     89  * kobj_read:
     90  *
     91  *	Utility function: read from the object.
     92  */
     93 static int
     94 kobj_read_vfs(kobj_t ko, void **basep, size_t size, off_t off,
     95 	bool allocate)
     96 {
     97 	size_t resid;
     98 	void *base;
     99 	int error;
    100 
    101 	KASSERT(ko->ko_source != NULL);
    102 
    103 	if (allocate) {
    104 		base = kmem_alloc(size, KM_SLEEP);
    105 	} else {
    106 		base = *basep;
    107 #ifdef DIAGNOSTIC
    108 		bool ok = false;
    109 		if ((uintptr_t)base >= (uintptr_t)ko->ko_text_address &&
    110 		    (uintptr_t)base + size <=
    111 		    (uintptr_t)ko->ko_text_address + ko->ko_text_size)
    112 			ok = true;
    113 		if ((uintptr_t)base >= (uintptr_t)ko->ko_data_address &&
    114 		    (uintptr_t)base + size <=
    115 		    (uintptr_t)ko->ko_data_address + ko->ko_data_size)
    116 			ok = true;
    117 		if ((uintptr_t)base >= (uintptr_t)ko->ko_rodata_address &&
    118 		    (uintptr_t)base + size <=
    119 		    (uintptr_t)ko->ko_rodata_address + ko->ko_rodata_size)
    120 			ok = true;
    121 		if (!ok)
    122 			panic("kobj_read_vfs: not in a dedicated segment");
    123 #endif
    124 	}
    125 
    126 	error = vn_rdwr(UIO_READ, ko->ko_source, base, size, off,
    127 	    UIO_SYSSPACE, IO_NODELOCKED, curlwp->l_cred, &resid,
    128 	    curlwp);
    129 
    130 	if (error == 0 && resid != 0) {
    131 		error = EINVAL;
    132 	}
    133 
    134 	if (allocate && error != 0) {
    135 		kmem_free(base, size);
    136 		base = NULL;
    137 	}
    138 
    139 	if (allocate)
    140 		*basep = base;
    141 
    142 	return error;
    143 }
    144 
    145 /*
    146  * kobj_load_vfs:
    147  *
    148  *	Load an object located in the file system.
    149  */
    150 int
    151 kobj_load_vfs(kobj_t *kop, const char *path, const bool nochroot)
    152 {
    153 	struct pathbuf *pb;
    154 	struct vnode *vp;
    155 	int error;
    156 	kobj_t ko;
    157 
    158 	KASSERT(path != NULL);
    159 	if (strchr(path, '/') == NULL)
    160 		return ENOENT;
    161 
    162 	ko = kmem_zalloc(sizeof(*ko), KM_SLEEP);
    163 	pb = pathbuf_create(path);
    164 	if (pb == NULL) {
    165 	 	kmem_free(ko, sizeof(*ko));
    166 		return ENOMEM;
    167 	}
    168 
    169 	error = vn_open(NULL, pb, (nochroot ? NOCHROOT : 0), FREAD, 0,
    170 	    &vp, NULL, NULL);
    171 
    172  	if (error != 0) {
    173 		pathbuf_destroy(pb);
    174 	 	kmem_free(ko, sizeof(*ko));
    175 	 	return error;
    176 	}
    177 
    178 	ko->ko_type = KT_VNODE;
    179 	kobj_setname(ko, path);
    180 	ko->ko_source = vp;
    181 	ko->ko_read = kobj_read_vfs;
    182 	ko->ko_close = kobj_close_vfs;
    183 	pathbuf_destroy(pb);
    184 
    185 	*kop = ko;
    186 	return kobj_load(ko);
    187 }
    188 
    189 #else /* MODULAR */
    190 
    191 int
    192 kobj_load_vfs(kobj_t *kop, const char *path, const bool nochroot)
    193 {
    194 
    195 	return ENOSYS;
    196 }
    197 
    198 #endif
    199