linux_exec_elf32.c revision 1.44
1 /* $NetBSD: linux_exec_elf32.c,v 1.44 2000/06/26 14:38:57 mrg Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 1998 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, Frank van der Linden and Eric Haszlakiewicz. 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * based on exec_aout.c, sunos_exec.c and svr4_exec.c 41 */ 42 43 #ifndef ELFSIZE 44 #define ELFSIZE 32 /* XXX should die */ 45 #endif 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/proc.h> 51 #include <sys/malloc.h> 52 #include <sys/namei.h> 53 #include <sys/vnode.h> 54 #include <sys/mount.h> 55 #include <sys/exec.h> 56 #include <sys/exec_elf.h> 57 58 #include <sys/mman.h> 59 #include <sys/syscallargs.h> 60 61 #include <vm/vm.h> 62 63 #include <machine/cpu.h> 64 #include <machine/reg.h> 65 66 #include <compat/linux/common/linux_types.h> 67 #include <compat/linux/common/linux_signal.h> 68 #include <compat/linux/common/linux_util.h> 69 #include <compat/linux/common/linux_exec.h> 70 #include <compat/linux/common/linux_machdep.h> 71 #include <compat/linux/common/linux_errno.h> 72 73 #include <compat/linux/linux_syscallargs.h> 74 #include <compat/linux/linux_syscall.h> 75 76 static int ELFNAME2(linux,signature) __P((struct proc *, struct exec_package *, 77 Elf_Ehdr *)); 78 #ifdef LINUX_GCC_SIGNATURE 79 static int ELFNAME2(linux,gcc_signature) __P((struct proc *p, 80 struct exec_package *, Elf_Ehdr *)); 81 #endif 82 83 #define LINUX_ELF_AUX_ARGSIZ howmany(sizeof(AuxInfo) * 8, sizeof(char *)) 84 85 86 extern char linux_sigcode[], linux_esigcode[]; 87 extern struct sysent linux_sysent[]; 88 extern char *linux_syscallnames[]; 89 90 struct emul ELFNAMEEND(emul_linux) = { 91 "linux", 92 native_to_linux_errno, 93 linux_sendsig, 94 LINUX_SYS_syscall, 95 LINUX_SYS_MAXSYSCALL, 96 linux_sysent, 97 linux_syscallnames, 98 LINUX_ELF_AUX_ARGSIZ, 99 ELFNAME(copyargs), 100 linux_setregs, 101 linux_sigcode, 102 linux_esigcode, 103 }; 104 105 106 #ifdef LINUX_GCC_SIGNATURE 107 /* 108 * Take advantage of the fact that all the linux binaries are compiled 109 * with gcc, and gcc sticks in the comment field a signature. Note that 110 * on SVR4 binaries, the gcc signature will follow the OS name signature, 111 * that will not be a problem. We don't bother to read in the string table, 112 * but we check all the progbits headers. 113 * 114 * XXX This only works in the i386. On the alpha (at least) 115 * XXX we have the same gcc signature which incorrectly identifies 116 * XXX NetBSD binaries as Linux. 117 */ 118 static int 119 ELFNAME2(linux,gcc_signature)(p, epp, eh) 120 struct proc *p; 121 struct exec_package *epp; 122 Elf_Ehdr *eh; 123 { 124 size_t shsize = sizeof(Elf_Shdr) * eh->e_shnum; 125 size_t i; 126 static const char signature[] = "\0GCC: (GNU) "; 127 char buf[sizeof(signature) - 1]; 128 Elf_Shdr *sh; 129 int error; 130 131 error = ENOEXEC; 132 sh = (Elf_Shdr *) malloc(shsize, M_TEMP, M_WAITOK); 133 134 if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_shoff, 135 (caddr_t) sh, shsize)) != 0) 136 goto out; 137 138 for (i = 0; i < eh->e_shnum; i++) { 139 Elf_Shdr *s = &sh[i]; 140 141 /* 142 * Identify candidates for the comment header; 143 * Header cannot have a load address, or flags and 144 * it must be large enough. 145 */ 146 if (s->sh_type != SHT_PROGBITS || 147 s->sh_addr != 0 || 148 s->sh_flags != 0 || 149 s->sh_size < sizeof(signature) - 1) 150 continue; 151 152 if ((error = ELFNAME(read_from)(p, epp->ep_vp, s->sh_offset, 153 (caddr_t) buf, sizeof(signature) - 1)) != 0) 154 goto out; 155 156 /* 157 * error is 0, if the signatures match we are done. 158 */ 159 #ifdef DEBUG_LINUX 160 printf("linux_gcc_sig: sig=%s\n", buf); 161 #endif 162 if (memcmp(buf, signature, sizeof(signature) - 1) == 0) 163 goto out; 164 } 165 166 out: 167 free(sh, M_TEMP); 168 #ifdef DEBUG_LINUX 169 printf("linux_gcc_sig: returning %d\n", error); 170 #endif 171 return error; 172 } 173 #endif 174 175 static int 176 ELFNAME2(linux,signature)(p, epp, eh) 177 struct proc *p; 178 struct exec_package *epp; 179 Elf_Ehdr *eh; 180 { 181 size_t i; 182 Elf_Phdr *ph; 183 Elf_Nhdr *notep; 184 size_t phsize; 185 int error = ENOEXEC; 186 187 phsize = eh->e_phnum * sizeof(Elf_Phdr); 188 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 189 if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_phoff, 190 (caddr_t) ph, phsize)) != 0) 191 goto out1; 192 193 for (i = 0; i < eh->e_phnum; i++) { 194 Elf_Phdr *ephp = &ph[i]; 195 u_int32_t ostype; 196 197 if (ephp->p_type != PT_INTERP /* XAX PT_NOTE */ 198 #if 0 199 || ephp->p_flags != 0 200 || ephp->p_filesz < sizeof(Elf_Nhdr)) 201 #endif 202 ) 203 continue; 204 205 notep = (Elf_Nhdr *)malloc(ephp->p_filesz+1, M_TEMP, M_WAITOK); 206 if ((error = ELFNAME(read_from)(p, epp->ep_vp, ephp->p_offset, 207 (caddr_t)notep, ephp->p_filesz)) != 0) 208 goto out3; 209 210 /* Check for "linux" in the intepreter name. */ 211 if (ephp->p_filesz < 8 + 5) { 212 error = ENOEXEC; 213 goto out3; 214 } 215 #ifdef DEBUG_LINUX 216 printf("linux_signature: interp=%s\n", notep); 217 #endif 218 if (strncmp(&((char *)notep)[8], "linux", 5) == 0 || 219 strncmp((char *)notep, "/lib/ld.so.", 11) == 0) { 220 error = 0; 221 goto out3; 222 } 223 224 goto out2; 225 226 /* XXX XAX Should handle NETBSD_TYPE_EMULNAME */ 227 if (notep->n_type != ELF_NOTE_TYPE_OSVERSION) { 228 free(notep, M_TEMP); 229 continue; 230 } 231 232 /* Check the name and description sizes. */ 233 if (notep->n_namesz != ELF_NOTE_GNU_NAMESZ || 234 notep->n_descsz != ELF_NOTE_GNU_DESCSZ) 235 goto out2; 236 237 /* Is the name "GNU\0"? */ 238 if (memcmp((notep + sizeof(Elf_Nhdr)), 239 ELF_NOTE_GNU_NAME, ELF_NOTE_GNU_NAMESZ)) 240 goto out2; 241 242 /* Make sure the OS is Linux */ 243 ostype = (u_int32_t)(*((u_int32_t *)notep + sizeof(Elf_Nhdr) + 244 notep->n_namesz)) & ELF_NOTE_GNU_OSMASK; 245 if (ostype != ELF_NOTE_GNU_OSLINUX) 246 goto out2; 247 248 /* All checks succeeded. */ 249 error = 0; 250 goto out3; 251 } 252 253 error = ENOEXEC; 254 255 out1: 256 free(ph, M_TEMP); 257 #ifdef DEBUG_LINUX 258 printf("linux_signature: out1=%d\n", error); 259 #endif 260 return error; 261 262 out2: 263 error = ENOEXEC; 264 out3: 265 free(notep, M_TEMP); 266 free(ph, M_TEMP); 267 #ifdef DEBUG_LINUX 268 printf("linux_signature: out2,3=%d\n", error); 269 #endif 270 return error; 271 } 272 273 int 274 ELFNAME2(linux,probe)(p, epp, eh, itp, pos) 275 struct proc *p; 276 struct exec_package *epp; 277 Elf_Ehdr *eh; 278 char *itp; 279 Elf_Addr *pos; 280 { 281 const char *bp; 282 int error; 283 size_t len; 284 285 if ((error = ELFNAME2(linux,signature)(p, epp, eh)) != 0) 286 #ifdef LINUX_GCC_SIGNATURE 287 if ((error = ELFNAME2(linux,gcc_signature)(p, epp, eh)) != 0) 288 return error; 289 #else 290 return error; 291 #endif 292 293 if (itp[0]) { 294 if ((error = emul_find(p, NULL, linux_emul_path, itp, &bp, 0))) 295 return error; 296 if ((error = copystr(bp, itp, MAXPATHLEN, &len))) 297 return error; 298 free((void *)bp, M_TEMP); 299 } 300 epp->ep_emul = &ELFNAMEEND(emul_linux); 301 *pos = ELF_NO_ADDR; 302 #ifdef DEBUG_LINUX 303 printf("linux_probe: returning 0\n"); 304 #endif 305 return 0; 306 } 307 308
Indexes created Tue Sep 23 14:10:03 GMT 2025