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 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 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 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 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 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