/* $NetBSD: nlist_elf32.c,v 1.4.2.1 1997/10/23 20:11:35 mellon Exp $ */ /* * 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 by Christopher G. Demetriou * for the NetBSD Project. * 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. */ #include #ifndef lint __RCSID("$NetBSD: nlist_elf32.c,v 1.4.2.1 1997/10/23 20:11:35 mellon Exp $"); #endif /* not lint */ /* If not included by nlist_elf64.c, ELFSIZE won't be defined. */ #ifndef ELFSIZE #define ELFSIZE 32 #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "extern.h" #if defined(NLIST_ELF32) || defined(NLIST_ELF64) #include #endif #if (defined(NLIST_ELF32) && (ELFSIZE == 32)) || \ (defined(NLIST_ELF64) && (ELFSIZE == 64)) #define CONCAT(x,y) __CONCAT(x,y) #define ELFNAME(x) CONCAT(elf,CONCAT(ELFSIZE,CONCAT(_,x))) #define ELFNAME2(x,y) CONCAT(x,CONCAT(_elf,CONCAT(ELFSIZE,CONCAT(_,y)))) #define ELFNAMEEND(x) CONCAT(x,CONCAT(_elf,ELFSIZE)) #define ELFDEFNNAME(x) CONCAT(ELF,CONCAT(ELFSIZE,CONCAT(_,x))) typedef struct nlist NLIST; #define _strx n_un.n_strx #define _name n_un.n_name #define badfmt(str) \ do { \ warnx("%s: %s: %s", kfile, str, strerror(EFTYPE)); \ punt(); \ } while (0) #define check(off, size) ((off < 0) || (off + size > mappedsize)) #define BAD do { rv = -1; goto out; } while (0) #define BADUNMAP do { rv = -1; goto unmap; } while (0) static const char *kfile; int ELFNAMEEND(create_knlist)(name, db) const char *name; DB *db; { struct stat st; struct nlist nbuf; DBT key, data; char *mappedfile, *symname, *fsymname, *tmpcp, *strtab; size_t mappedsize, symnamesize, fsymnamesize; Elf_Ehdr *ehdrp; Elf_Shdr *shdrp, *symshdrp, *symstrshdrp; Elf_Sym *symp; Elf_Off shdr_off; Elf_Word shdr_size; #if (ELFSIZE == 32) Elf32_Half nshdr; #elif (ELFSIZE == 64) Elf64_Half nshdr; #endif unsigned long i, nsyms; int fd, rv; rv = -1; #ifdef __GNUC__ /* fix compiler warnings */ symshdrp = NULL; symstrshdrp = NULL; #endif /* * Open and map the whole file. If we can't open/stat it, * something bad is going on so we punt. */ kfile = name; if ((fd = open(name, O_RDONLY, 0)) < 0) { warn("%s", kfile); punt(); } if (fstat(fd, &st) < 0) { warn("%s", kfile); punt(); } if (st.st_size > SIZE_T_MAX) BAD; /* * Map the file in its entirety. */ mappedsize = st.st_size; mappedfile = mmap(NULL, mappedsize, PROT_READ, 0, fd, 0); if (mappedfile == (char *)-1) BAD; /* * Make sure we can access the executable's header * directly, and make sure the recognize the executable * as an ELF binary. */ if (check(0, sizeof *ehdrp)) BADUNMAP; ehdrp = (Elf_Ehdr *)&mappedfile[0]; if (memcmp(ehdrp->e_ident, Elf_e_ident, Elf_e_siz)) BADUNMAP; switch (ehdrp->e_machine) { ELFDEFNNAME(MACHDEP_ID_CASES) default: BADUNMAP; } /* * We've recognized it as an ELF binary. From here * on out, all errors are fatal. */ /* * Find the symbol list and string table. */ nshdr = ehdrp->e_shnum; shdr_off = ehdrp->e_shoff; shdr_size = ehdrp->e_shentsize * nshdr; if (check(shdr_off, shdr_size) || (sizeof *shdrp != ehdrp->e_shentsize)) badfmt("bogus section header table"); shdrp = (Elf_Shdr *)&mappedfile[shdr_off]; for (i = 0; i < nshdr; i++) { if (shdrp[i].sh_type == Elf_sht_symtab) { symshdrp = &shdrp[i]; symstrshdrp = &shdrp[shdrp[i].sh_link]; } } if (symshdrp->sh_offset == 0) badfmt("stripped"); if (check(symshdrp->sh_offset, symshdrp->sh_size)) badfmt("bogus symbol section header"); if (check(symstrshdrp->sh_offset, symstrshdrp->sh_size)) badfmt("bogus symbol string section header"); symp = (Elf_Sym *)&mappedfile[symshdrp->sh_offset]; nsyms = symshdrp->sh_size / sizeof(*symp); strtab = &mappedfile[symstrshdrp->sh_offset]; /* * Set up the data item, pointing to a nlist structure. * which we fill in for each symbol. */ data.data = (u_char *)&nbuf; data.size = sizeof(nbuf); /* * Create a buffer (to be expanded later, if necessary) * to hold symbol names after we've added underscores * to them. */ symnamesize = 1024; if ((symname = malloc(symnamesize)) == NULL) { warn("malloc"); punt(); } /* * Read each symbol and enter it into the database. */ for (i = 0; i < nsyms; i++) { /* * No symbol name; ignore this symbol. */ if (symp[i].st_name == 0) continue; /* * Find symbol name, copy it (with added underscore) to * temporary buffer, and prepare the database key for * insertion. */ fsymname = &strtab[symp[i].st_name]; fsymnamesize = strlen(fsymname) + 1; while (symnamesize < fsymnamesize + 1) { symnamesize *= 2; if ((symname = realloc(symname, symnamesize)) == NULL) { warn("malloc"); punt(); } } strcpy(symname, "_"); strcat(symname, fsymname); key.data = symname; key.size = strlen((char *)key.data); /* * Convert the symbol information into an nlist structure, * as best we can. */ nbuf.n_value = symp[i].st_value; switch (ELF_SYM_TYPE(symp[i].st_info)) { default: case Elf_estt_notype: nbuf.n_type = N_UNDF; break; case Elf_estt_object: nbuf.n_type = N_DATA; break; case Elf_estt_func: nbuf.n_type = N_TEXT; break; case Elf_estt_file: nbuf.n_type = N_FN; break; } if (ELF_SYM_BIND(symp[i].st_info) != Elf_estb_local) nbuf.n_type |= N_EXT; nbuf.n_desc = 0; /* XXX */ nbuf.n_other = 0; /* XXX */ /* * Enter the symbol into the database. */ if (db->put(db, &key, &data, 0)) { warn("record enter"); punt(); } /* * If it's the kernel version string, we've gotta keep * some extra data around. Under a seperate key, * we enter the first line (i.e. up to the first newline, * with the newline replaced by a NUL to terminate the * entered string) of the version string. */ if (strcmp((char *)key.data, VRS_SYM) == 0) { key.data = (u_char *)VRS_KEY; key.size = sizeof(VRS_KEY) - 1; /* Find the version string, relative to its section */ data.data = strdup(&mappedfile[nbuf.n_value - shdrp[symp[i].st_shndx].sh_addr + shdrp[symp[i].st_shndx].sh_offset]); /* assumes newline terminates version. */ if ((tmpcp = strchr(data.data, '\n')) != NULL) *tmpcp = '\0'; data.size = strlen((char *)data.data); if (db->put(db, &key, &data, 0)) { warn("record enter"); punt(); } /* free pointer created by strdup(). */ free(data.data); /* Restore to original values */ data.data = (u_char *)&nbuf; data.size = sizeof(nbuf); } } rv = 0; unmap: munmap(mappedfile, mappedsize); out: return (rv); } #endif