1 /* $NetBSD: compat_util.c,v 1.43 2009/12/14 04:09:38 mrg 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 1.43 2009/12/14 04:09:38 mrg 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/malloc.h> 74 #include <sys/vnode.h> 75 #include <sys/syslog.h> 76 #include <sys/mount.h> 77 78 #include <compat/common/compat_util.h> 79 80 void 81 emul_find_root(struct lwp *l, struct exec_package *epp) 82 { 83 struct vnode *vp; 84 const char *emul_path; 85 86 if (epp->ep_emul_root != NULL) 87 /* We've already found it */ 88 return; 89 90 emul_path = epp->ep_esch->es_emul->e_path; 91 if (emul_path == NULL) 92 /* Emulation doesn't have a root */ 93 return; 94 95 if (namei_simple_kernel(emul_path, NSM_FOLLOW_NOEMULROOT, &vp) != 0) 96 /* emulation root doesn't exist */ 97 return; 98 99 epp->ep_emul_root = vp; 100 } 101 102 /* 103 * Search the alternate path for dynamic binary interpreter. If not found 104 * there, check if the interpreter exists in within 'proper' tree. 105 */ 106 int 107 emul_find_interp(struct lwp *l, struct exec_package *epp, const char *itp) 108 { 109 int error; 110 struct nameidata nd; 111 unsigned int flags; 112 113 /* If we haven't found the emulation root already, do so now */ 114 /* Maybe we should remember failures somehow ? */ 115 if (epp->ep_esch->es_emul->e_path != 0 && epp->ep_emul_root == NULL) 116 emul_find_root(l, epp); 117 118 if (epp->ep_interp != NULL) 119 vrele(epp->ep_interp); 120 121 /* We need to use the emulation root for the new program, 122 * not the one for the current process. */ 123 if (epp->ep_emul_root == NULL) 124 flags = FOLLOW; 125 else { 126 nd.ni_erootdir = epp->ep_emul_root; 127 /* hack: Pass in the emulation path for ktrace calls */ 128 nd.ni_next = epp->ep_esch->es_emul->e_path; 129 flags = FOLLOW | TRYEMULROOT | EMULROOTSET; 130 } 131 132 NDINIT(&nd, LOOKUP, flags, UIO_SYSSPACE, itp); 133 error = namei(&nd); 134 if (error != 0) { 135 epp->ep_interp = NULL; 136 return error; 137 } 138 139 /* Save interpreter in case we actually need to load it */ 140 epp->ep_interp = nd.ni_vp; 141 142 return 0; 143 } 144 145 /* 146 * Translate one set of flags to another, based on the entries in 147 * the given table. If 'leftover' is specified, it is filled in 148 * with any flags which could not be translated. 149 */ 150 unsigned long 151 emul_flags_translate(const struct emul_flags_xtab *tab, 152 unsigned long in, unsigned long *leftover) 153 { 154 unsigned long out; 155 156 for (out = 0; tab->omask != 0; tab++) { 157 if ((in & tab->omask) == tab->oval) { 158 in &= ~tab->omask; 159 out |= tab->nval; 160 } 161 } 162 if (leftover != NULL) 163 *leftover = in; 164 return (out); 165 } 166 167 void 168 compat_offseterr(struct vnode *vp, const char *msg) 169 { 170 struct mount *mp; 171 172 mp = vp->v_mount; 173 174 log(LOG_ERR, "%s: dir offset too large on fs %s (mounted from %s)\n", 175 msg, mp->mnt_stat.f_mntonname, mp->mnt_stat.f_mntfromname); 176 uprintf("%s: dir offset too large for emulated program\n", msg); 177 } 178 179 /* 180 * Look for native NetBSD compatibility libraries, usually interp-ABI. 181 * It returns 0 if it changed the interpreter, otherwise it returns 182 * the error from namei(). Callers should not try any more processing 183 * if this returns 0, and probably should just ignore the return value. 184 */ 185 int 186 compat_elf_check_interp(struct exec_package *epp, 187 char *interp, 188 const char *interp_suffix) 189 { 190 int error = 0; 191 192 /* 193 * Don't look for something else, if someone has already found and 194 * setup the ep_interp already. 195 */ 196 if (interp && epp->ep_interp == NULL) { 197 /* 198 * If the path is exactly "/usr/libexec/ld.elf_so", first 199 * try to see if "/usr/libexec/ld.elf_so-<abi>" exists 200 * and if so, use that instead. 201 */ 202 if (strcmp(interp, "/usr/libexec/ld.elf_so") == 0 || 203 strcmp(interp, "/libexec/ld.elf_so") == 0) { 204 struct vnode *vp; 205 char *path; 206 207 path = PNBUF_GET(); 208 snprintf(path, MAXPATHLEN, "%s-%s", interp, interp_suffix); 209 error = namei_simple_kernel(path, 210 NSM_FOLLOW_NOEMULROOT, &vp); 211 /* 212 * If that worked, replace interpreter in case we 213 * actually need to load it. 214 */ 215 if (error == 0) { 216 epp->ep_interp = vp; 217 snprintf(interp, MAXPATHLEN, "%s", path); 218 } 219 PNBUF_PUT(path); 220 } 221 } 222 return error; 223 } 224