nlist_elf32.c revision 1.2
1 /* $NetBSD: nlist_elf32.c,v 1.2 1996/09/30 23:51:05 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1996 Christopher G. Demetriou. All rights reserved. 5 * Copyright (c) 1989, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)nlist.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 static char rcsid[] = "$NetBSD: nlist_elf32.c,v 1.2 1996/09/30 23:51:05 cgd Exp $"; 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 /* If not included by nlist_elf64.c, ELFSIZE won't be defined. */ 46 #ifndef ELFSIZE 47 #define ELFSIZE 32 48 #endif 49 50 #include <sys/param.h> 51 #include <sys/mman.h> 52 #include <sys/stat.h> 53 #include <sys/file.h> 54 55 #include <errno.h> 56 #include <stdio.h> 57 #include <string.h> 58 #include <unistd.h> 59 #include <a.out.h> /* for 'struct nlist' declaration */ 60 61 #include "nlist_private.h" 62 #if defined(NLIST_ELF32) || defined(NLIST_ELF64) 63 #include <sys/exec_elf.h> 64 #endif 65 66 #if (defined(NLIST_ELF32) && (ELFSIZE == 32)) || \ 67 (defined(NLIST_ELF64) && (ELFSIZE == 64)) 68 69 #define CONCAT(x,y) __CONCAT(x,y) 70 #define ELFNAME(x) CONCAT(elf,CONCAT(ELFSIZE,CONCAT(_,x))) 71 #define ELFNAME2(x,y) CONCAT(x,CONCAT(_elf,CONCAT(ELFSIZE,CONCAT(_,y)))) 72 #define ELFNAMEEND(x) CONCAT(x,CONCAT(_elf,ELFSIZE)) 73 #define ELFDEFNNAME(x) CONCAT(ELF,CONCAT(ELFSIZE,CONCAT(_,x))) 74 75 int 76 ELFNAMEEND(__fdnlist)(fd, list) 77 register int fd; 78 register struct nlist *list; 79 { 80 register struct nlist *p; 81 register caddr_t strtab; 82 register Elf32_Word symsize, symstrsize; 83 register Elf32_Off symoff = 0, symstroff; 84 register long nent, cc, i; 85 Elf_Sym sbuf[1024]; 86 Elf_Sym *s; 87 Elf_Ehdr ehdr; 88 Elf_Shdr *shdr = NULL; 89 Elf_Word shdr_size; 90 struct stat st; 91 92 /* Make sure obj is OK */ 93 if (lseek(fd, (off_t)0, SEEK_SET) == -1 || 94 read(fd, &ehdr, sizeof(Elf_Ehdr)) != sizeof(Elf_Ehdr) || 95 fstat(fd, &st) < 0) 96 return (-1); 97 98 if (bcmp(ehdr.e_ident, Elf_e_ident, Elf_e_siz)) 99 return (-1); 100 101 switch (ehdr.e_machine) { 102 ELFDEFNNAME(MACHDEP_ID_CASES) 103 104 default: 105 return (-1); 106 } 107 108 /* calculate section header table size */ 109 shdr_size = ehdr.e_shentsize * ehdr.e_shnum; 110 111 /* Make sure it's not too big to mmap */ 112 if (shdr_size > SIZE_T_MAX) { 113 errno = EFBIG; 114 return (-1); 115 } 116 117 /* mmap section header table */ 118 shdr = (Elf_Shdr *)mmap(NULL, (size_t)shdr_size, 119 PROT_READ, 0, fd, ehdr.e_shoff); 120 if (shdr == (Elf_Shdr *)-1) 121 return (-1); 122 123 /* 124 * Find the symbol table entry and it's corresponding 125 * string table entry. Version 1.1 of the ABI states 126 * that there is only one symbol table but that this 127 * could change in the future. 128 */ 129 for (i = 0; i < ehdr.e_shnum; i++) { 130 if (shdr[i].sh_type == Elf_sht_symtab) { 131 symoff = shdr[i].sh_offset; 132 symsize = shdr[i].sh_size; 133 symstroff = shdr[shdr[i].sh_link].sh_offset; 134 symstrsize = shdr[shdr[i].sh_link].sh_size; 135 break; 136 } 137 } 138 139 /* Flush the section header table */ 140 munmap((caddr_t)shdr, shdr_size); 141 142 /* Check for files too large to mmap. */ 143 /* XXX is this really possible? */ 144 if (symstrsize > SIZE_T_MAX) { 145 errno = EFBIG; 146 return (-1); 147 } 148 /* 149 * Map string table into our address space. This gives us 150 * an easy way to randomly access all the strings, without 151 * making the memory allocation permanent as with malloc/free 152 * (i.e., munmap will return it to the system). 153 */ 154 strtab = mmap(NULL, (size_t)symstrsize, PROT_READ, 0, fd, symstroff); 155 if (strtab == (char *)-1) 156 return (-1); 157 /* 158 * clean out any left-over information for all valid entries. 159 * Type and value defined to be 0 if not found; historical 160 * versions cleared other and desc as well. Also figure out 161 * the largest string length so don't read any more of the 162 * string table than we have to. 163 * 164 * XXX clearing anything other than n_type and n_value violates 165 * the semantics given in the man page. 166 */ 167 nent = 0; 168 for (p = list; !ISLAST(p); ++p) { 169 p->n_type = 0; 170 p->n_other = 0; 171 p->n_desc = 0; 172 p->n_value = 0; 173 ++nent; 174 } 175 176 /* Don't process any further if object is stripped. */ 177 /* ELFism - dunno if stripped by looking at header */ 178 if (symoff == 0) 179 goto done; 180 181 if (lseek(fd, symoff, SEEK_SET) == -1) { 182 nent = -1; 183 goto done; 184 } 185 186 while (symsize > 0) { 187 cc = MIN(symsize, sizeof(sbuf)); 188 if (read(fd, sbuf, cc) != cc) 189 break; 190 symsize -= cc; 191 for (s = sbuf; cc > 0; ++s, cc -= sizeof(*s)) { 192 register int soff = s->st_name; 193 194 if (soff == 0) 195 continue; 196 197 for (p = list; !ISLAST(p); p++) { 198 char *nlistname; 199 200 nlistname = p->n_un.n_name; 201 if (*nlistname == '_') 202 nlistname++; 203 204 if (!strcmp(&strtab[soff], nlistname)) { 205 p->n_value = s->st_value; 206 207 switch(ELF_SYM_TYPE(s->st_info)) { 208 case Elf_estt_notype: 209 p->n_type = N_UNDF; 210 break; 211 case Elf_estt_object: 212 p->n_type = N_DATA; 213 break; 214 case Elf_estt_func: 215 p->n_type = N_TEXT; 216 break; 217 case Elf_estt_file: 218 p->n_type = N_FN; 219 break; 220 } 221 if (ELF_SYM_BIND(s->st_info) != 222 Elf_estb_local) 223 p->n_type |= N_EXT; 224 p->n_desc = 0; 225 p->n_other = 0; 226 if (--nent <= 0) 227 break; 228 } 229 } 230 } 231 } 232 done: 233 munmap(strtab, symstrsize); 234 235 return (nent); 236 } 237 238 #endif 239
Indexes created Sat Sep 27 22:09:54 GMT 2025