1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 1997-1999 by Sun Microsystems, Inc. 24 * All rights reserved. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <stdio.h> 30 #include <fcntl.h> 31 #include <ctype.h> 32 #include <string.h> 33 #include <signal.h> 34 #include <errno.h> 35 #include <stdlib.h> 36 #include <stdarg.h> 37 #include <unistd.h> 38 #include <limits.h> 39 #include <sys/types.h> 40 #include <sys/stat.h> 41 42 #include <libelf.h> 43 #include <link.h> 44 #include <elf.h> 45 #if defined(sun) 46 #include <sys/machelf.h> 47 48 #include <kstat.h> 49 #else 50 /* FreeBSD */ 51 #include <sys/elf.h> 52 #include <sys/ksyms.h> 53 #endif 54 #include <sys/cpuvar.h> 55 56 typedef struct syment { 57 uintptr_t addr; 58 char *name; 59 size_t size; 60 } syment_t; 61 62 static syment_t *symbol_table; 63 static int nsyms, maxsyms; 64 static char maxsymname[64]; 65 66 #if defined(sun) 67 #ifdef _ELF64 68 #define elf_getshdr elf64_getshdr 69 #else 70 #define elf_getshdr elf32_getshdr 71 #endif 72 #endif 73 74 static void 75 add_symbol(char *name, uintptr_t addr, size_t size) 76 { 77 syment_t *sep; 78 79 if (nsyms >= maxsyms) { 80 maxsyms += 10000; 81 symbol_table = realloc(symbol_table, maxsyms * sizeof (*sep)); 82 if (symbol_table == NULL) { 83 (void) fprintf(stderr, "can't allocate symbol table\n"); 84 exit(3); 85 } 86 } 87 sep = &symbol_table[nsyms++]; 88 89 sep->name = name; 90 sep->addr = addr; 91 sep->size = size; 92 } 93 94 static void 95 remove_symbol(uintptr_t addr) 96 { 97 int i; 98 syment_t *sep = symbol_table; 99 100 for (i = 0; i < nsyms; i++, sep++) 101 if (sep->addr == addr) 102 sep->addr = 0; 103 } 104 105 #if defined(sun) 106 static void 107 fake_up_certain_popular_kernel_symbols(void) 108 { 109 kstat_ctl_t *kc; 110 kstat_t *ksp; 111 char *name; 112 113 if ((kc = kstat_open()) == NULL) 114 return; 115 116 for (ksp = kc->kc_chain; ksp; ksp = ksp->ks_next) { 117 if (strcmp(ksp->ks_module, "cpu_info") == 0) { 118 if ((name = malloc(20)) == NULL) 119 break; 120 /* 121 * For consistency, keep cpu[0] and toss cpu0 122 * or any other such symbols. 123 */ 124 if (ksp->ks_instance == 0) 125 remove_symbol((uintptr_t)ksp->ks_private); 126 (void) sprintf(name, "cpu[%d]", ksp->ks_instance); 127 add_symbol(name, (uintptr_t)ksp->ks_private, 128 sizeof (struct cpu)); 129 } 130 } 131 (void) kstat_close(kc); 132 } 133 #else 134 /* FreeBSD */ 135 static void 136 fake_up_certain_popular_kernel_symbols(void) 137 { 138 char *name; 139 uintptr_t addr; 140 int i; 141 142 /* Good for up to 256 CPUs */ 143 for(i=0; i < 256; i++) { 144 if ((name = malloc(20)) == NULL) 145 break; 146 (void) sprintf(name, "cpu[%d]", i); 147 addr = 0x01000000 + (i << 16); 148 add_symbol(name, addr, sizeof (uintptr_t)); 149 } 150 } 151 #endif /* !defined(sun) */ 152 153 static int 154 symcmp(const void *p1, const void *p2) 155 { 156 uintptr_t a1 = ((syment_t *)p1)->addr; 157 uintptr_t a2 = ((syment_t *)p2)->addr; 158 159 if (a1 < a2) 160 return (-1); 161 if (a1 > a2) 162 return (1); 163 return (0); 164 } 165 166 int 167 symtab_init(void) 168 { 169 Elf *elf; 170 Elf_Scn *scn = NULL; 171 Sym *symtab, *symp, *lastsym; 172 char *strtab; 173 uint_t cnt; 174 int fd; 175 int i; 176 int strindex = -1; 177 #if !defined(sun) 178 void *ksyms; 179 size_t sz; 180 #endif 181 182 #if defined(__FreeBSD__) 183 if ((fd = open("/dev/ksyms", O_RDONLY)) == -1) { 184 if (errno == ENOENT && modfind("ksyms") == -1) { 185 kldload("ksyms"); 186 fd = open("/dev/ksyms", O_RDONLY); 187 } 188 if (fd == -1) 189 return (-1); 190 } 191 #else 192 if ((fd = open("/dev/ksyms", O_RDONLY)) == -1) 193 return (-1); 194 #endif 195 196 #if defined(sun) 197 (void) elf_version(EV_CURRENT); 198 199 elf = elf_begin(fd, ELF_C_READ, NULL); 200 #else 201 /* FreeBSD */ 202 /* 203 * XXX - libelf needs to be fixed so it will work with 204 * non 'ordinary' files like /dev/ksyms. The following 205 * is a work around for now. 206 */ 207 if (elf_version(EV_CURRENT) == EV_NONE) { 208 close(fd); 209 return (-1); 210 } 211 if (ioctl(fd, KIOCGSIZE, &sz) < 0) { 212 close(fd); 213 return (-1); 214 } 215 if (ioctl(fd, KIOCGADDR, &ksyms) < 0) { 216 close(fd); 217 return (-1); 218 } 219 if ((elf = elf_memory(ksyms, sz)) == NULL) { 220 close(fd); 221 return (-1); 222 } 223 #endif 224 225 for (cnt = 1; (scn = elf_nextscn(elf, scn)) != NULL; cnt++) { 226 Shdr *shdr = elf_getshdr(scn); 227 if (shdr->sh_type == SHT_SYMTAB) { 228 symtab = (Sym *)elf_getdata(scn, NULL)->d_buf; 229 nsyms = shdr->sh_size / shdr->sh_entsize; 230 strindex = shdr->sh_link; 231 } 232 } 233 234 for (cnt = 1; (scn = elf_nextscn(elf, scn)) != NULL; cnt++) { 235 if (cnt == strindex) 236 strtab = (char *)elf_getdata(scn, NULL)->d_buf; 237 } 238 239 lastsym = symtab + nsyms; 240 nsyms = 0; 241 for (symp = symtab; symp < lastsym; symp++) 242 if ((uint_t)ELF32_ST_TYPE(symp->st_info) <= STT_FUNC && 243 symp->st_size != 0) 244 add_symbol(symp->st_name + strtab, 245 (uintptr_t)symp->st_value, (size_t)symp->st_size); 246 247 fake_up_certain_popular_kernel_symbols(); 248 (void) sprintf(maxsymname, "0x%lx", ULONG_MAX); 249 add_symbol(maxsymname, ULONG_MAX, 1); 250 251 qsort(symbol_table, nsyms, sizeof (syment_t), symcmp); 252 253 /* 254 * Destroy all duplicate symbols, then sort it again. 255 */ 256 for (i = 0; i < nsyms - 1; i++) 257 if (symbol_table[i].addr == symbol_table[i + 1].addr) 258 symbol_table[i].addr = 0; 259 260 qsort(symbol_table, nsyms, sizeof (syment_t), symcmp); 261 262 while (symbol_table[1].addr == 0) { 263 symbol_table++; 264 nsyms--; 265 } 266 symbol_table[0].name = "(usermode)"; 267 symbol_table[0].addr = 0; 268 symbol_table[0].size = 1; 269 270 close(fd); 271 return (0); 272 } 273 274 char * 275 addr_to_sym(uintptr_t addr, uintptr_t *offset, size_t *sizep) 276 { 277 int lo = 0; 278 int hi = nsyms - 1; 279 int mid; 280 syment_t *sep; 281 282 while (hi - lo > 1) { 283 mid = (lo + hi) / 2; 284 if (addr >= symbol_table[mid].addr) { 285 lo = mid; 286 } else { 287 hi = mid; 288 } 289 } 290 sep = &symbol_table[lo]; 291 *offset = addr - sep->addr; 292 *sizep = sep->size; 293 return (sep->name); 294 } 295 296 uintptr_t 297 sym_to_addr(char *name) 298 { 299 int i; 300 syment_t *sep = symbol_table; 301 302 for (i = 0; i < nsyms; i++) { 303 if (strcmp(name, sep->name) == 0) 304 return (sep->addr); 305 sep++; 306 } 307 return (0); 308 } 309 310 size_t 311 sym_size(char *name) 312 { 313 int i; 314 syment_t *sep = symbol_table; 315 316 for (i = 0; i < nsyms; i++) { 317 if (strcmp(name, sep->name) == 0) 318 return (sep->size); 319 sep++; 320 } 321 return (0); 322 } 323