linux_exec_elf32.c revision 1.39
1 /* $NetBSD: linux_exec_elf32.c,v 1.39 1998/10/23 10:54:58 veego 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 #include <vm/vm_param.h> 63 #include <vm/vm_map.h> 64 65 #include <machine/cpu.h> 66 #include <machine/reg.h> 67 68 #include <compat/linux/common/linux_types.h> 69 #include <compat/linux/common/linux_signal.h> 70 #include <compat/linux/common/linux_util.h> 71 #include <compat/linux/common/linux_exec.h> 72 #include <compat/linux/common/linux_machdep.h> 73 #include <compat/linux/common/linux_errno.h> 74 75 #include <compat/linux/linux_syscallargs.h> 76 #include <compat/linux/linux_syscall.h> 77 78 static int ELFNAME2(linux,signature) __P((struct proc *, struct exec_package *, 79 Elf_Ehdr *)); 80 #ifdef LINUX_GCC_SIGNATURE 81 static int ELFNAME2(linux,gcc_signature) __P((struct proc *p, 82 struct exec_package *, Elf_Ehdr *)); 83 #endif 84 85 #define LINUX_ELF_AUX_ARGSIZ (sizeof(AuxInfo) * 8 / sizeof(char *)) 86 87 88 extern char linux_sigcode[], linux_esigcode[]; 89 extern struct sysent linux_sysent[]; 90 extern char *linux_syscallnames[]; 91 92 struct emul ELFNAMEEND(emul_linux) = { 93 "linux", 94 native_to_linux_errno, 95 linux_sendsig, 96 LINUX_SYS_syscall, 97 LINUX_SYS_MAXSYSCALL, 98 linux_sysent, 99 linux_syscallnames, 100 LINUX_ELF_AUX_ARGSIZ, 101 ELFNAME(copyargs), 102 linux_setregs, 103 linux_sigcode, 104 linux_esigcode, 105 }; 106 107 108 #ifdef LINUX_GCC_SIGNATURE 109 /* 110 * Take advantage of the fact that all the linux binaries are compiled 111 * with gcc, and gcc sticks in the comment field a signature. Note that 112 * on SVR4 binaries, the gcc signature will follow the OS name signature, 113 * that will not be a problem. We don't bother to read in the string table, 114 * but we check all the progbits headers. 115 * 116 * XXX This only works in the i386. On the alpha (at least) 117 * XXX we have the same gcc signature which incorrectly identifies 118 * XXX NetBSD binaries as Linux. 119 */ 120 static int 121 ELFNAME2(linux,gcc_signature)(p, epp, eh) 122 struct proc *p; 123 struct exec_package *epp; 124 Elf_Ehdr *eh; 125 { 126 size_t shsize = sizeof(Elf_Shdr) * eh->e_shnum; 127 size_t i; 128 static const char signature[] = "\0GCC: (GNU) "; 129 char buf[sizeof(signature) - 1]; 130 Elf_Shdr *sh; 131 int error; 132 133 error = ENOEXEC; 134 sh = (Elf_Shdr *) malloc(shsize, M_TEMP, M_WAITOK); 135 136 if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_shoff, 137 (caddr_t) sh, shsize)) != 0) 138 goto out; 139 140 for (i = 0; i < eh->e_shnum; i++) { 141 Elf_Shdr *s = &sh[i]; 142 143 /* 144 * Identify candidates for the comment header; 145 * Header cannot have a load address, or flags and 146 * it must be large enough. 147 */ 148 if (s->sh_type != Elf_sht_progbits || 149 s->sh_addr != 0 || 150 s->sh_flags != 0 || 151 s->sh_size < sizeof(signature) - 1) 152 continue; 153 154 if ((error = ELFNAME(read_from)(p, epp->ep_vp, s->sh_offset, 155 (caddr_t) buf, sizeof(signature) - 1)) != 0) 156 goto out; 157 158 /* 159 * error is 0, if the signatures match we are done. 160 */ 161 #ifdef DEBUG_LINUX 162 printf("linux_gcc_sig: sig=%s\n", buf); 163 #endif 164 if (memcmp(buf, signature, sizeof(signature) - 1) == 0) 165 goto out; 166 } 167 168 out: 169 free(sh, M_TEMP); 170 #ifdef DEBUG_LINUX 171 printf("linux_gcc_sig: returning %d\n", error); 172 #endif 173 return error; 174 } 175 #endif 176 177 static int 178 ELFNAME2(linux,signature)(p, epp, eh) 179 struct proc *p; 180 struct exec_package *epp; 181 Elf_Ehdr *eh; 182 { 183 size_t i; 184 Elf_Phdr *ph; 185 Elf_Note *notep; 186 char *testp; 187 size_t phsize; 188 int error = ENOEXEC; 189 190 phsize = eh->e_phnum * sizeof(Elf_Phdr); 191 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 192 if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_phoff, 193 (caddr_t) ph, phsize)) != 0) 194 goto out1; 195 196 for (i = 0; i < eh->e_phnum; i++) { 197 Elf_Phdr *ephp = &ph[i]; 198 u_int32_t ostype; 199 200 if (ephp->p_type != Elf_pt_interp /* XAX pt_note */ 201 #if 0 202 || ephp->p_flags != 0 203 || ephp->p_filesz < sizeof(Elf_Note)) 204 #endif 205 ) 206 continue; 207 208 notep = (Elf_Note *)malloc(ephp->p_filesz, M_TEMP, M_WAITOK); 209 if ((error = ELFNAME(read_from)(p, epp->ep_vp, ephp->p_offset, 210 (caddr_t)notep, ephp->p_filesz)) != 0) 211 goto out3; 212 213 testp = (char *)notep; 214 testp[16] = '\0'; 215 #ifdef DEBUG_LINUX 216 printf("linux_signature: interp=%s\n", testp); 217 #endif 218 if (strncmp(&testp[8], "linux", 5) == 0) { 219 error = 0; 220 goto out3; 221 } 222 223 goto out2; 224 225 /* XXX XAX Should handle NETBSD_TYPE_EMULNAME */ 226 if (notep->type != ELF_NOTE_TYPE_OSVERSION) { 227 free(notep, M_TEMP); 228 continue; 229 } 230 231 /* Check the name and description sizes. */ 232 if (notep->namesz != ELF_NOTE_GNU_NAMESZ || 233 notep->descsz != ELF_NOTE_GNU_DESCSZ) 234 goto out2; 235 236 /* Is the name "GNU\0"? */ 237 if (memcmp((notep + sizeof(Elf_Note)), 238 ELF_NOTE_GNU_NAME, ELF_NOTE_GNU_NAMESZ)) 239 goto out2; 240 241 /* Make sure the OS is Linux */ 242 ostype = (u_int32_t)(*((u_int32_t *)notep + sizeof(Elf_Note) + 243 notep->namesz)) & ELF_NOTE_GNU_OSMASK; 244 if (ostype != ELF_NOTE_GNU_OSLINUX) 245 goto out2; 246 247 /* All checks succeeded. */ 248 error = 0; 249 goto out3; 250 } 251 252 error = ENOEXEC; 253 254 out1: 255 free(ph, M_TEMP); 256 #ifdef DEBUG_LINUX 257 printf("linux_signature: out1=%d\n", error); 258 #endif 259 return error; 260 261 out2: 262 error = ENOEXEC; 263 out3: 264 free(notep, M_TEMP); 265 free(ph, M_TEMP); 266 #ifdef DEBUG_LINUX 267 printf("linux_signature: out2,3=%d\n", error); 268 #endif 269 return error; 270 } 271 272 int 273 ELFNAME2(linux,probe)(p, epp, eh, itp, pos) 274 struct proc *p; 275 struct exec_package *epp; 276 Elf_Ehdr *eh; 277 char *itp; 278 Elf_Addr *pos; 279 { 280 char *bp; 281 int error; 282 size_t len; 283 284 if ((error = ELFNAME2(linux,signature)(p, epp, eh)) != 0) 285 #ifdef LINUX_GCC_SIGNATURE 286 if ((error = ELFNAME2(linux,gcc_signature)(p, epp, eh)) != 0) 287 return error; 288 #else 289 return error; 290 #endif 291 292 if (itp[0]) { 293 if ((error = emul_find(p, NULL, linux_emul_path, itp, &bp, 0))) 294 return error; 295 if ((error = copystr(bp, itp, MAXPATHLEN, &len))) 296 return error; 297 free(bp, M_TEMP); 298 } 299 epp->ep_emul = &ELFNAMEEND(emul_linux); 300 *pos = ELF_NO_ADDR; 301 #ifdef DEBUG_LINUX 302 printf("linux_probe: returning 0\n"); 303 #endif 304 return 0; 305 } 306 307
Indexes created Thu Sep 25 02:09:54 GMT 2025