/* $NetBSD: elf32.c,v 1.12 2025/12/20 16:13:21 jkoshy Exp $ */ /*- * Copyright (c) 2006 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Andrew Doran. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1996 Christopher G. Demetriou * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the * NetBSD Project. See http://www.NetBSD.org/ for * information about NetBSD. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>> */ #include <sys/cdefs.h> #if !defined(lint) __RCSID("$NetBSD: elf32.c,v 1.12 2025/12/20 16:13:21 jkoshy Exp $"); #endif #ifndef ELFSIZE #define ELFSIZE 32 #endif #include <sys/param.h> #include <sys/exec_elf.h> #include <sys/queue.h> #include <dev/lockstat.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <err.h> #include "extern.h" #if (ELFSIZE == 32) #define NAME(x) x##32 #elif (ELFSIZE == 64) #define NAME(x) x##64 #endif static int nsyms; static Elf_Sym *symp; static char *strp; int NAME(loadsym)(int fd) { Elf_Shdr symhdr, strhdr; Elf_Ehdr ehdr; size_t sz; off_t off; int i; /* * Read the ELF header and make sure it's OK. */ if (pread(fd, &ehdr, sizeof(ehdr), 0) != sizeof(ehdr)) return -1; if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || ehdr.e_ident[EI_CLASS] != ELFCLASS) return -1; switch (ehdr.e_machine) { ELFDEFNNAME(MACHDEP_ID_CASES) default: return -1; } /* * Find the symbol table header, and make sure the binary isn't * stripped. */ off = ehdr.e_shoff; for (i = 0; i < ehdr.e_shnum; i++, off += sizeof(symhdr)) { sz = pread(fd, &symhdr, sizeof(symhdr), off); if (sz != sizeof(symhdr)) err(EXIT_FAILURE, "pread (section headers)"); if (symhdr.sh_type == SHT_SYMTAB) break; } if (i == ehdr.e_shnum || symhdr.sh_offset == 0) err(EXIT_FAILURE, "namelist is stripped"); /* * Pull in the string table header, and then read in both the symbol * table and string table proper. * * XXX We can't use mmap(), as /dev/ksyms doesn't support mmap yet. */ off = ehdr.e_shoff + symhdr.sh_link * sizeof(symhdr); if (pread(fd, &strhdr, sizeof(strhdr), off) != sizeof(strhdr)) err(EXIT_FAILURE, "pread"); if ((symp = malloc(symhdr.sh_size)) == NULL) err(EXIT_FAILURE, "malloc (symbol table)"); sz = pread(fd, symp, symhdr.sh_size, symhdr.sh_offset); if (sz != symhdr.sh_size) err(EXIT_FAILURE, "pread (symbol table)"); if ((strp = malloc(strhdr.sh_size)) == NULL) err(EXIT_FAILURE, "malloc (string table)"); sz = pread(fd, strp, strhdr.sh_size, strhdr.sh_offset); if (sz != strhdr.sh_size) err(EXIT_FAILURE, "pread (string table)"); nsyms = (int)(symhdr.sh_size / sizeof(Elf_Sym)); return 0; } int NAME(findsym)(findsym_t find, char *name, uintptr_t *start, uintptr_t *end) { uintptr_t sa, ea; int i, off; Elf_Byte st; switch (find) { case LOCK_BYNAME: case LOCK_BYADDR: st = STT_OBJECT; break; case FUNC_BYNAME: case FUNC_BYADDR: st = STT_FUNC; break; default: return -1; } #ifdef dump_core static int lastptr[FIND_MAX]; for (i = lastptr[find];;) { #else for (i = 0; i < nsyms; i++) { #endif switch (find) { case LOCK_BYNAME: case FUNC_BYNAME: if (ELF_ST_TYPE(symp[i].st_info) != st) break; if (strcmp(&strp[symp[i].st_name], name) != 0) break; *start = (uintptr_t)symp[i].st_value; *end = *start + (uintptr_t)symp[i].st_size; goto found; case LOCK_BYADDR: case FUNC_BYADDR: if (ELF_ST_TYPE(symp[i].st_info) != st) break; sa = (uintptr_t)symp[i].st_value; ea = sa + (uintptr_t)symp[i].st_size - 1; if (*start < sa || *start > ea) break; off = (int)(*start - sa); *start = sa; if (end != NULL) *end = ea; if (name == NULL) goto found; if (off == 0) strlcpy(name, &strp[symp[i].st_name], NAME_SIZE); else snprintf(name, NAME_SIZE, "%s+%x", &strp[symp[i].st_name], off); goto found; default: break; } #ifdef dump_core if (++i >= nsyms) i = 0; if (i == lastptr[find]) return -1; #endif } return -1; found: #ifdef dump_core lastptr[find] = i; #endif return 0; }
