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 #include <stdio.h> 28 #include <fcntl.h> 29 #include <ctype.h> 30 #include <string.h> 31 #include <signal.h> 32 #include <errno.h> 33 #include <stdlib.h> 34 #include <stdarg.h> 35 #include <unistd.h> 36 #include <limits.h> 37 #include <sys/types.h> 38 #include <sys/stat.h> 39 40 #include <libelf.h> 41 #include <link.h> 42 #include <elf.h> 43 #include <sys/machelf.h> 44 45 #include <kstat.h> 46 #include <sys/cpuvar.h> 47 48 typedef struct syment { 49 uintptr_t addr; 50 char *name; 51 size_t size; 52 } syment_t; 53 54 static syment_t *symbol_table; 55 static int nsyms, maxsyms; 56 static char maxsymname[64]; 57 58 #ifdef _ELF64 59 #define elf_getshdr elf64_getshdr 60 #else 61 #define elf_getshdr elf32_getshdr 62 #endif 63 64 static void 65 add_symbol(char *name, uintptr_t addr, size_t size) 66 { 67 syment_t *sep; 68 69 if (nsyms >= maxsyms) { 70 maxsyms += 10000; 71 symbol_table = realloc(symbol_table, maxsyms * sizeof (*sep)); 72 if (symbol_table == NULL) { 73 (void) fprintf(stderr, "can't allocate symbol table\n"); 74 exit(3); 75 } 76 } 77 sep = &symbol_table[nsyms++]; 78 79 sep->name = name; 80 sep->addr = addr; 81 sep->size = size; 82 } 83 84 static void 85 remove_symbol(uintptr_t addr) 86 { 87 int i; 88 syment_t *sep = symbol_table; 89 90 for (i = 0; i < nsyms; i++, sep++) 91 if (sep->addr == addr) 92 sep->addr = 0; 93 } 94 95 static void 96 fake_up_certain_popular_kernel_symbols(void) 97 { 98 kstat_ctl_t *kc; 99 kstat_t *ksp; 100 char *name; 101 102 if ((kc = kstat_open()) == NULL) 103 return; 104 105 for (ksp = kc->kc_chain; ksp; ksp = ksp->ks_next) { 106 if (strcmp(ksp->ks_module, "cpu_info") == 0) { 107 if ((name = malloc(20)) == NULL) 108 break; 109 /* 110 * For consistency, keep cpu[0] and toss cpu0 111 * or any other such symbols. 112 */ 113 if (ksp->ks_instance == 0) 114 remove_symbol((uintptr_t)ksp->ks_private); 115 (void) sprintf(name, "cpu[%d]", ksp->ks_instance); 116 add_symbol(name, (uintptr_t)ksp->ks_private, 117 sizeof (struct cpu)); 118 } 119 } 120 (void) kstat_close(kc); 121 } 122 123 static int 124 symcmp(const void *p1, const void *p2) 125 { 126 uintptr_t a1 = ((syment_t *)p1)->addr; 127 uintptr_t a2 = ((syment_t *)p2)->addr; 128 129 if (a1 < a2) 130 return (-1); 131 if (a1 > a2) 132 return (1); 133 return (0); 134 } 135 136 int 137 symtab_init(void) 138 { 139 Elf *elf; 140 Elf_Scn *scn = NULL; 141 Sym *symtab, *symp, *lastsym; 142 char *strtab; 143 uint_t cnt; 144 int fd; 145 int i; 146 int strindex = -1; 147 148 if ((fd = open("/dev/ksyms", O_RDONLY)) == -1) 149 return (-1); 150 151 (void) elf_version(EV_CURRENT); 152 153 elf = elf_begin(fd, ELF_C_READ, NULL); 154 155 for (cnt = 1; (scn = elf_nextscn(elf, scn)) != NULL; cnt++) { 156 Shdr *shdr = elf_getshdr(scn); 157 if (shdr->sh_type == SHT_SYMTAB) { 158 symtab = (Sym *)elf_getdata(scn, NULL)->d_buf; 159 nsyms = shdr->sh_size / shdr->sh_entsize; 160 strindex = shdr->sh_link; 161 } 162 } 163 164 for (cnt = 1; (scn = elf_nextscn(elf, scn)) != NULL; cnt++) { 165 if (cnt == strindex) 166 strtab = (char *)elf_getdata(scn, NULL)->d_buf; 167 } 168 169 lastsym = symtab + nsyms; 170 nsyms = 0; 171 for (symp = symtab; symp < lastsym; symp++) 172 if ((uint_t)ELF32_ST_TYPE(symp->st_info) <= STT_FUNC && 173 symp->st_size != 0) 174 add_symbol(symp->st_name + strtab, 175 (uintptr_t)symp->st_value, (size_t)symp->st_size); 176 177 fake_up_certain_popular_kernel_symbols(); 178 (void) sprintf(maxsymname, "0x%lx", ULONG_MAX); 179 add_symbol(maxsymname, ULONG_MAX, 1); 180 181 qsort(symbol_table, nsyms, sizeof (syment_t), symcmp); 182 183 /* 184 * Destroy all duplicate symbols, then sort it again. 185 */ 186 for (i = 0; i < nsyms - 1; i++) 187 if (symbol_table[i].addr == symbol_table[i + 1].addr) 188 symbol_table[i].addr = 0; 189 190 qsort(symbol_table, nsyms, sizeof (syment_t), symcmp); 191 192 while (symbol_table[1].addr == 0) { 193 symbol_table++; 194 nsyms--; 195 } 196 symbol_table[0].name = "(usermode)"; 197 symbol_table[0].addr = 0; 198 symbol_table[0].size = 1; 199 200 return (0); 201 } 202 203 char * 204 addr_to_sym(uintptr_t addr, uintptr_t *offset, size_t *sizep) 205 { 206 int lo = 0; 207 int hi = nsyms - 1; 208 int mid; 209 syment_t *sep; 210 211 while (hi - lo > 1) { 212 mid = (lo + hi) / 2; 213 if (addr >= symbol_table[mid].addr) { 214 lo = mid; 215 } else { 216 hi = mid; 217 } 218 } 219 sep = &symbol_table[lo]; 220 *offset = addr - sep->addr; 221 *sizep = sep->size; 222 return (sep->name); 223 } 224 225 uintptr_t 226 sym_to_addr(char *name) 227 { 228 int i; 229 syment_t *sep = symbol_table; 230 231 for (i = 0; i < nsyms; i++) { 232 if (strcmp(name, sep->name) == 0) 233 return (sep->addr); 234 sep++; 235 } 236 return ((uintptr_t)NULL); 237 } 238 239 size_t 240 sym_size(char *name) 241 { 242 int i; 243 syment_t *sep = symbol_table; 244 245 for (i = 0; i < nsyms; i++) { 246 if (strcmp(name, sep->name) == 0) 247 return (sep->size); 248 sep++; 249 } 250 return (0); 251 } 252