1 /* $NetBSD: compat_util.c,v 1.46 2014/11/09 17:48:07 maxv Exp $ */
2
3 /*-
4 * Copyright (c) 1994 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas and Frank van der Linden.
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) 2008, 2009 Matthew R. Green
34 * All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 3. The name of the author may not be used to endorse or promote products
45 * derived from this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
48 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
49 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
50 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
51 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
52 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
53 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
54 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
55 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
56 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
57 * SUCH DAMAGE.
58 */
59
60 #include <sys/cdefs.h>
61 __KERNEL_RCSID(0, "$NetBSD: compat_util.c,v 1.46 2014/11/09 17:48:07 maxv Exp $");
62
63 #include <sys/param.h>
64 #include <sys/systm.h>
65 #include <sys/namei.h>
66 #include <sys/proc.h>
67 #include <sys/file.h>
68 #include <sys/stat.h>
69 #include <sys/filedesc.h>
70 #include <sys/exec.h>
71 #include <sys/ioctl.h>
72 #include <sys/kernel.h>
73 #include <sys/vnode.h>
74 #include <sys/syslog.h>
75 #include <sys/mount.h>
76
77 #include <compat/common/compat_util.h>
78
79 void
emul_find_root(struct lwp * l,struct exec_package * epp)80 emul_find_root(struct lwp *l, struct exec_package *epp)
81 {
82 struct vnode *vp;
83 const char *emul_path;
84
85 if (epp->ep_emul_root != NULL)
86 /* We've already found it */
87 return;
88
89 emul_path = epp->ep_esch->es_emul->e_path;
90 if (emul_path == NULL)
91 /* Emulation doesn't have a root */
92 return;
93
94 if (namei_simple_kernel(emul_path, NSM_FOLLOW_NOEMULROOT, &vp) != 0)
95 /* emulation root doesn't exist */
96 return;
97
98 epp->ep_emul_root = vp;
99 }
100
101 /*
102 * Search the alternate path for dynamic binary interpreter. If not found
103 * there, check if the interpreter exists in within 'proper' tree.
104 */
105 int
emul_find_interp(struct lwp * l,struct exec_package * epp,const char * itp)106 emul_find_interp(struct lwp *l, struct exec_package *epp, const char *itp)
107 {
108 int error;
109 struct pathbuf *pb;
110 struct nameidata nd;
111 unsigned int flags;
112
113 pb = pathbuf_create(itp);
114 if (pb == NULL) {
115 return ENOMEM;
116 }
117
118 /* If we haven't found the emulation root already, do so now */
119 /* Maybe we should remember failures somehow ? */
120 if (epp->ep_esch->es_emul->e_path != 0 && epp->ep_emul_root == NULL)
121 emul_find_root(l, epp);
122
123 if (epp->ep_interp != NULL)
124 vrele(epp->ep_interp);
125
126 /* We need to use the emulation root for the new program,
127 * not the one for the current process. */
128 if (epp->ep_emul_root == NULL)
129 flags = FOLLOW;
130 else {
131 nd.ni_erootdir = epp->ep_emul_root;
132 /* hack: Pass in the emulation path for ktrace calls */
133 nd.ni_next = epp->ep_esch->es_emul->e_path;
134 flags = FOLLOW | TRYEMULROOT | EMULROOTSET;
135 }
136
137 NDINIT(&nd, LOOKUP, flags, pb);
138 error = namei(&nd);
139 if (error != 0) {
140 epp->ep_interp = NULL;
141 pathbuf_destroy(pb);
142 return error;
143 }
144
145 /* Save interpreter in case we actually need to load it */
146 epp->ep_interp = nd.ni_vp;
147
148 pathbuf_destroy(pb);
149
150 return 0;
151 }
152
153 /*
154 * Translate one set of flags to another, based on the entries in
155 * the given table. If 'leftover' is specified, it is filled in
156 * with any flags which could not be translated.
157 */
158 unsigned long
emul_flags_translate(const struct emul_flags_xtab * tab,unsigned long in,unsigned long * leftover)159 emul_flags_translate(const struct emul_flags_xtab *tab,
160 unsigned long in, unsigned long *leftover)
161 {
162 unsigned long out;
163
164 for (out = 0; tab->omask != 0; tab++) {
165 if ((in & tab->omask) == tab->oval) {
166 in &= ~tab->omask;
167 out |= tab->nval;
168 }
169 }
170 if (leftover != NULL)
171 *leftover = in;
172 return (out);
173 }
174
175 void
compat_offseterr(struct vnode * vp,const char * msg)176 compat_offseterr(struct vnode *vp, const char *msg)
177 {
178 struct mount *mp;
179
180 mp = vp->v_mount;
181
182 log(LOG_ERR, "%s: dir offset too large on fs %s (mounted from %s)\n",
183 msg, mp->mnt_stat.f_mntonname, mp->mnt_stat.f_mntfromname);
184 uprintf("%s: dir offset too large for emulated program\n", msg);
185 }
186
187 /*
188 * Look for native NetBSD compatibility libraries, usually interp-ABI.
189 * It returns 0 if it changed the interpreter, otherwise it returns
190 * the error from namei(). Callers should not try any more processing
191 * if this returns 0, and probably should just ignore the return value.
192 */
193 int
compat_elf_check_interp(struct exec_package * epp,char * interp,const char * interp_suffix)194 compat_elf_check_interp(struct exec_package *epp,
195 char *interp,
196 const char *interp_suffix)
197 {
198 int error = 0;
199
200 /*
201 * Don't look for something else, if someone has already found and
202 * setup the ep_interp already.
203 */
204 if (interp && epp->ep_interp == NULL) {
205 /*
206 * If the path is exactly "/usr/libexec/ld.elf_so", first
207 * try to see if "/usr/libexec/ld.elf_so-<abi>" exists
208 * and if so, use that instead.
209 */
210 if (strcmp(interp, "/usr/libexec/ld.elf_so") == 0 ||
211 strcmp(interp, "/libexec/ld.elf_so") == 0) {
212 struct vnode *vp;
213 char *path;
214
215 path = PNBUF_GET();
216 snprintf(path, MAXPATHLEN, "%s-%s", interp, interp_suffix);
217 error = namei_simple_kernel(path,
218 NSM_FOLLOW_NOEMULROOT, &vp);
219 /*
220 * If that worked, replace interpreter in case we
221 * actually need to load it.
222 */
223 if (error == 0) {
224 epp->ep_interp = vp;
225 snprintf(interp, MAXPATHLEN, "%s", path);
226 }
227 PNBUF_PUT(path);
228 }
229 }
230 return error;
231 }
232