elf32.c revision 1.6
1 /* $NetBSD: elf32.c,v 1.6 2007/07/14 13:30:43 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 2006 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Andrew Doran. 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 * Copyright (c) 1996 Christopher G. Demetriou 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed for the 54 * NetBSD Project. See http://www.NetBSD.org/ for 55 * information about NetBSD. 56 * 4. The name of the author may not be used to endorse or promote products 57 * derived from this software without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 60 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 61 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 62 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 63 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 64 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 65 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 66 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 67 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 68 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 69 * 70 * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>> 71 */ 72 73 #include <sys/cdefs.h> 74 #if !defined(lint) 75 __RCSID("$NetBSD: elf32.c,v 1.6 2007/07/14 13:30:43 ad Exp $"); 76 #endif 77 78 #ifndef ELFSIZE 79 #define ELFSIZE 32 80 #endif 81 82 #include <sys/param.h> 83 #include <sys/exec_elf.h> 84 #include <sys/queue.h> 85 86 #include <dev/lockstat.h> 87 88 #include <stdio.h> 89 #include <stdlib.h> 90 #include <string.h> 91 #include <unistd.h> 92 #include <err.h> 93 94 #include "extern.h" 95 96 #if (ELFSIZE == 32) 97 #define NAME(x) x##32 98 #elif (ELFSIZE == 64) 99 #define NAME(x) x##64 100 #endif 101 102 static int nsyms; 103 static Elf_Sym *symp; 104 static char *strp; 105 106 int 107 NAME(loadsym)(int fd) 108 { 109 Elf_Shdr symhdr, strhdr; 110 Elf_Ehdr ehdr; 111 size_t sz; 112 off_t off; 113 int i; 114 115 /* 116 * Read the ELF header and make sure it's OK. 117 */ 118 if (pread(fd, &ehdr, sizeof(ehdr), 0) != sizeof(ehdr)) 119 return -1; 120 121 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || 122 ehdr.e_ident[EI_CLASS] != ELFCLASS) 123 return -1; 124 125 switch (ehdr.e_machine) { 126 ELFDEFNNAME(MACHDEP_ID_CASES) 127 default: 128 return -1; 129 } 130 131 /* 132 * Find the symbol table header, and make sure the binary isn't 133 * stripped. 134 */ 135 off = ehdr.e_shoff; 136 for (i = 0; i < ehdr.e_shnum; i++, off += sizeof(symhdr)) { 137 sz = pread(fd, &symhdr, sizeof(symhdr), off); 138 if (sz != sizeof(symhdr)) 139 err(EXIT_FAILURE, "pread (section headers)"); 140 if (symhdr.sh_type == SHT_SYMTAB) 141 break; 142 } 143 if (i == ehdr.e_shnum || symhdr.sh_offset == 0) 144 err(EXIT_FAILURE, "namelist is stripped"); 145 146 /* 147 * Pull in the string table header, and then read in both the symbol 148 * table and string table proper. 149 * 150 * XXX We can't use mmap(), as /dev/ksyms doesn't support mmap yet. 151 */ 152 off = ehdr.e_shoff + symhdr.sh_link * sizeof(symhdr); 153 if (pread(fd, &strhdr, sizeof(strhdr), off) != sizeof(strhdr)) 154 err(EXIT_FAILURE, "pread"); 155 156 if ((symp = malloc(symhdr.sh_size)) == NULL) 157 err(EXIT_FAILURE, "malloc (symbol table)"); 158 sz = pread(fd, symp, symhdr.sh_size, symhdr.sh_offset ); 159 if (sz != symhdr.sh_size) 160 err(EXIT_FAILURE, "pread (symbol table)"); 161 162 if ((strp = malloc(strhdr.sh_size)) == NULL) 163 err(EXIT_FAILURE, "malloc (string table)"); 164 sz = pread(fd, strp, strhdr.sh_size, strhdr.sh_offset); 165 if (sz != strhdr.sh_size) 166 err(EXIT_FAILURE, "pread (string table)"); 167 168 nsyms = (int)(symhdr.sh_size / sizeof(Elf_Sym)); 169 170 return 0; 171 } 172 173 int 174 NAME(findsym)(findsym_t find, char *name, uintptr_t *start, uintptr_t *end) 175 { 176 static int lastptr[FIND_MAX]; 177 uintptr_t sa, ea; 178 int i, rv, st, off; 179 180 switch (find) { 181 case LOCK_BYNAME: 182 case LOCK_BYADDR: 183 st = STT_OBJECT; 184 break; 185 case FUNC_BYNAME: 186 case FUNC_BYADDR: 187 st = STT_FUNC; 188 break; 189 default: 190 return -1; 191 } 192 193 rv = -1; 194 195 #ifdef dump_core 196 for (i = lastptr[find];;) { 197 #else 198 for (i = 0; i < nsyms; i++) { 199 #endif 200 switch (find) { 201 case LOCK_BYNAME: 202 case FUNC_BYNAME: 203 if (ELF_ST_TYPE(symp[i].st_info) != st) 204 break; 205 if (strcmp(&strp[symp[i].st_name], name) != 0) 206 break; 207 *start = (uintptr_t)symp[i].st_value; 208 *end = *start + (uintptr_t)symp[i].st_size; 209 goto found; 210 211 case LOCK_BYADDR: 212 case FUNC_BYADDR: 213 if (ELF_ST_TYPE(symp[i].st_info) != st) 214 break; 215 sa = (uintptr_t)symp[i].st_value; 216 ea = sa + (uintptr_t)symp[i].st_size - 1; 217 if (*start < sa || *start > ea) 218 break; 219 off = (int)(*start - sa); 220 *start = sa; 221 if (end != NULL) 222 *end = ea; 223 if (name == NULL) 224 goto found; 225 if (off == 0) 226 strlcpy(name, &strp[symp[i].st_name], 227 NAME_SIZE); 228 else 229 snprintf(name, NAME_SIZE, "%s+%x", 230 &strp[symp[i].st_name], off); 231 goto found; 232 233 default: 234 break; 235 } 236 237 #ifdef dump_core 238 if (++i >= nsyms) 239 i = 0; 240 if (i == lastptr[find]) 241 return -1; 242 #endif 243 } 244 245 return -1; 246 247 found: 248 lastptr[find] = i; 249 return 0; 250 } 251
Indexes created Tue Sep 30 11:09:46 GMT 2025