/* * Copyright 2003-2006 Gentoo Foundation * Distributed under the terms of the GNU General Public License v2 * $Header: /var/cvsroot/gentoo-projects/pax-utils/scanelf.c,v 1.176 2007/04/08 19:14:31 solar Exp $ * * Copyright 2003-2006 Ned Ludd - * Copyright 2004-2006 Mike Frysinger - */ #include "paxinc.h" static const char *rcsid = "$Id: scanelf.c,v 1.176 2007/04/08 19:14:31 solar Exp $"; #define argv0 "scanelf" #define IS_MODIFIER(c) (c == '%' || c == '#' || c == '+') /* prototypes */ static int file_matches_list(const char *filename, char **matchlist); static int scanelf_elfobj(elfobj *elf); static int scanelf_elf(const char *filename, int fd, size_t len); static int scanelf_archive(const char *filename, int fd, size_t len); static int scanelf_file(const char *filename, const struct stat *st_cache); static int scanelf_dir(const char *path); static void scanelf_ldpath(void); static void scanelf_envpath(void); static void usage(int status); static char **get_split_env(const char *envvar); static void parseenv(void); static int parseargs(int argc, char *argv[]); static char *xstrdup(const char *s); static void *xmalloc(size_t size); static void *xrealloc(void *ptr, size_t size); static void xstrncat(char **dst, const char *src, size_t *curr_len, size_t n); #define xstrcat(dst,src,curr_len) xstrncat(dst,src,curr_len,0) static inline void xchrcat(char **dst, const char append, size_t *curr_len); static int rematch(const char *regex, const char *match, int cflags); /* variables to control behavior */ static char match_etypes[126] = ""; static char *ldpaths[256]; static char scan_ldpath = 0; static char scan_envpath = 0; static char scan_symlink = 1; static char scan_archives = 0; static char dir_recurse = 0; static char dir_crossmount = 1; static char show_pax = 0; static char show_phdr = 0; static char show_textrel = 0; static char show_rpath = 0; static char show_needed = 0; static char show_interp = 0; static char show_bind = 0; static char show_soname = 0; static char show_textrels = 0; static char show_banner = 1; static char be_quiet = 0; static char be_verbose = 0; static char be_wewy_wewy_quiet = 0; static char be_semi_verbose = 0; static char *find_sym = NULL, *versioned_symname = NULL; static char *find_lib = NULL; static char *find_section = NULL; static char *out_format = NULL; static char *search_path = NULL; static char fix_elf = 0; static char g_match = 0; static char use_ldcache = 0; static char **qa_textrels = NULL; static char **qa_execstack = NULL; static char **qa_wx_load = NULL; int match_bits = 0; caddr_t ldcache = 0; size_t ldcache_size = 0; unsigned long setpax = 0UL; int has_objdump = 0; /* find the path to a file by name */ static char *which(const char *fname) { static char fullpath[BUFSIZ]; char *path, *p; path = getenv("PATH"); if (!path) return NULL; path = xstrdup(path); while ((p = strrchr(path, ':')) != NULL) { snprintf(fullpath, sizeof(fullpath), "%s/%s", p + 1, fname); *p = 0; if (access(fullpath, R_OK) != (-1)) { free(path); return (char *) fullpath; } } free(path); return NULL; } /* 1 on failure. 0 otherwise */ static int rematch(const char *regex, const char *match, int cflags) { regex_t preg; int ret; if ((match == NULL) || (regex == NULL)) return EXIT_FAILURE; if ((ret = regcomp(&preg, regex, cflags))) { char err[256]; if (regerror(ret, &preg, err, sizeof(err))) fprintf(stderr, "regcomp failed: %s", err); else fprintf(stderr, "regcomp failed"); return EXIT_FAILURE; } ret = regexec(&preg, match, 0, NULL, 0); regfree(&preg); return ret; } /* sub-funcs for scanelf_file() */ static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **tab) { /* find the best SHT_DYNSYM and SHT_STRTAB sections */ #define GET_SYMTABS(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Shdr *symtab, *strtab, *dynsym, *dynstr; \ /* debug sections */ \ symtab = SHDR ## B (elf_findsecbyname(elf, ".symtab")); \ strtab = SHDR ## B (elf_findsecbyname(elf, ".strtab")); \ /* runtime sections */ \ dynsym = SHDR ## B (elf_findsecbyname(elf, ".dynsym")); \ dynstr = SHDR ## B (elf_findsecbyname(elf, ".dynstr")); \ if (symtab && dynsym) { \ *sym = (void*)((EGET(symtab->sh_size) > EGET(dynsym->sh_size)) ? symtab : dynsym); \ } else { \ *sym = (void*)(symtab ? symtab : dynsym); \ } \ if (strtab && dynstr) { \ *tab = (void*)((EGET(strtab->sh_size) > EGET(dynstr->sh_size)) ? strtab : dynstr); \ } else { \ *tab = (void*)(strtab ? strtab : dynstr); \ } \ } GET_SYMTABS(32) GET_SYMTABS(64) } static char *scanelf_file_pax(elfobj *elf, char *found_pax) { static char ret[7]; unsigned long i, shown; if (!show_pax) return NULL; shown = 0; memset(&ret, 0, sizeof(ret)); if (elf->phdr) { #define SHOW_PAX(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ for (i = 0; i < EGET(ehdr->e_phnum); i++) { \ if (EGET(phdr[i].p_type) != PT_PAX_FLAGS) \ continue; \ if (fix_elf && setpax) { \ /* set the paxctl flags */ \ ESET(phdr[i].p_flags, setpax); \ } \ if (be_quiet && (EGET(phdr[i].p_flags) == (PF_NOEMUTRAMP | PF_NORANDEXEC))) \ continue; \ memcpy(ret, pax_short_pf_flags(EGET(phdr[i].p_flags)), 6); \ *found_pax = 1; \ ++shown; \ break; \ } \ } SHOW_PAX(32) SHOW_PAX(64) } if (fix_elf && setpax) { /* set the chpax settings */ if (elf->elf_class == ELFCLASS32) { if (EHDR32(elf->ehdr)->e_type == ET_DYN || EHDR32(elf->ehdr)->e_type == ET_EXEC) ESET(EHDR32(elf->ehdr)->e_ident[EI_PAX], pax_pf2hf_flags(setpax)); } else { if (EHDR64(elf->ehdr)->e_type == ET_DYN || EHDR64(elf->ehdr)->e_type == ET_EXEC) ESET(EHDR64(elf->ehdr)->e_ident[EI_PAX], pax_pf2hf_flags(setpax)); } } /* fall back to EI_PAX if no PT_PAX was found */ if (!*ret) { static char *paxflags; paxflags = pax_short_hf_flags(EI_PAX_FLAGS(elf)); if (!be_quiet || (be_quiet && EI_PAX_FLAGS(elf))) { *found_pax = 1; return (be_wewy_wewy_quiet ? NULL : paxflags); } strncpy(ret, paxflags, sizeof(ret)); } if (be_wewy_wewy_quiet || (be_quiet && !shown)) return NULL; else return ret; } static char *scanelf_file_phdr(elfobj *elf, char *found_phdr, char *found_relro, char *found_load) { static char ret[12]; char *found; unsigned long i, shown, multi_stack, multi_relro, multi_load; int max_pt_load; if (!show_phdr) return NULL; memcpy(ret, "--- --- ---\0", 12); shown = 0; multi_stack = multi_relro = multi_load = 0; max_pt_load = elf_max_pt_load(elf); #define NOTE_GNU_STACK ".note.GNU-stack" #define SHOW_PHDR(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Off offset; \ uint32_t flags, check_flags; \ if (elf->phdr != NULL) { \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ for (i = 0; i < EGET(ehdr->e_phnum); ++i) { \ if (EGET(phdr[i].p_type) == PT_GNU_STACK) { \ if (multi_stack++) \ warnf("%s: multiple PT_GNU_STACK's !?", elf->filename); \ if (file_matches_list(elf->filename, qa_execstack)) \ continue; \ found = found_phdr; \ offset = 0; \ check_flags = PF_X; \ } else if (EGET(phdr[i].p_type) == PT_GNU_RELRO) { \ if (multi_relro++) \ warnf("%s: multiple PT_GNU_RELRO's !?", elf->filename); \ found = found_relro; \ offset = 4; \ check_flags = PF_X; \ } else if (EGET(phdr[i].p_type) == PT_LOAD) { \ if (ehdr->e_type == ET_DYN || ehdr->e_type == ET_EXEC) \ if (multi_load++ > max_pt_load) \ warnf("%s: more than %i PT_LOAD's !?", elf->filename, max_pt_load); \ if (file_matches_list(elf->filename, qa_wx_load)) \ continue; \ found = found_load; \ offset = 8; \ check_flags = PF_W|PF_X; \ } else \ continue; \ flags = EGET(phdr[i].p_flags); \ if (be_quiet && ((flags & check_flags) != check_flags)) \ continue; \ if ((EGET(phdr[i].p_type) != PT_LOAD) && (fix_elf && ((flags & PF_X) != flags))) { \ ESET(phdr[i].p_flags, flags & (PF_X ^ (size_t)-1)); \ ret[3] = ret[7] = '!'; \ flags = EGET(phdr[i].p_flags); \ } \ memcpy(ret+offset, gnu_short_stack_flags(flags), 3); \ *found = 1; \ ++shown; \ } \ } else if (elf->shdr != NULL) { \ /* no program headers which means this is prob an object file */ \ Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \ Elf ## B ## _Shdr *strtbl = shdr + EGET(ehdr->e_shstrndx); \ char *str; \ if ((void*)strtbl > (void*)elf->data_end) \ goto skip_this_shdr##B; \ check_flags = SHF_WRITE|SHF_EXECINSTR; \ for (i = 0; i < EGET(ehdr->e_shnum); ++i) { \ if (EGET(shdr[i].sh_type) != SHT_PROGBITS) continue; \ offset = EGET(strtbl->sh_offset) + EGET(shdr[i].sh_name); \ str = elf->data + offset; \ if (str > elf->data + offset + sizeof(NOTE_GNU_STACK)) continue; \ if (!strcmp(str, NOTE_GNU_STACK)) { \ if (multi_stack++) warnf("%s: multiple .note.GNU-stack's !?", elf->filename); \ flags = EGET(shdr[i].sh_flags); \ if (be_quiet && ((flags & check_flags) != check_flags)) \ continue; \ ++*found_phdr; \ shown = 1; \ if (flags & SHF_WRITE) ret[0] = 'W'; \ if (flags & SHF_ALLOC) ret[1] = 'A'; \ if (flags & SHF_EXECINSTR) ret[2] = 'X'; \ if (flags & 0xFFFFFFF8) warn("Invalid section flags for GNU-stack"); \ break; \ } \ } \ skip_this_shdr##B: \ if (!multi_stack) { \ if (file_matches_list(elf->filename, qa_execstack)) \ return NULL; \ *found_phdr = 1; \ shown = 1; \ memcpy(ret, "!WX", 3); \ } \ } \ } SHOW_PHDR(32) SHOW_PHDR(64) if (be_wewy_wewy_quiet || (be_quiet && !shown)) return NULL; else return ret; } static const char *scanelf_file_textrel(elfobj *elf, char *found_textrel) { static const char *ret = "TEXTREL"; unsigned long i; if (!show_textrel && !show_textrels) return NULL; if (file_matches_list(elf->filename, qa_textrels)) return NULL; if (elf->phdr) { #define SHOW_TEXTREL(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Dyn *dyn; \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ Elf ## B ## _Off offset; \ for (i = 0; i < EGET(ehdr->e_phnum); i++) { \ if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \ offset = EGET(phdr[i].p_offset); \ if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \ dyn = DYN ## B (elf->data + offset); \ while (EGET(dyn->d_tag) != DT_NULL) { \ if (EGET(dyn->d_tag) == DT_TEXTREL) { /*dyn->d_tag != DT_FLAGS)*/ \ *found_textrel = 1; \ /*if (dyn->d_un.d_val & DF_TEXTREL)*/ \ return (be_wewy_wewy_quiet ? NULL : ret); \ } \ ++dyn; \ } \ } } SHOW_TEXTREL(32) SHOW_TEXTREL(64) } if (be_quiet || be_wewy_wewy_quiet) return NULL; else return " - "; } static char *scanelf_file_textrels(elfobj *elf, char *found_textrels, char *found_textrel) { unsigned long s, r, rmax; void *symtab_void, *strtab_void, *text_void; if (!show_textrels) return NULL; /* don't search for TEXTREL's if the ELF doesn't have any */ if (!*found_textrel) scanelf_file_textrel(elf, found_textrel); if (!*found_textrel) return NULL; scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void); text_void = elf_findsecbyname(elf, ".text"); if (symtab_void && strtab_void && text_void && elf->shdr) { #define SHOW_TEXTRELS(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Shdr *shdr = SHDR ## B (elf->shdr); \ Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \ Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \ Elf ## B ## _Shdr *text = SHDR ## B (text_void); \ Elf ## B ## _Addr vaddr = EGET(text->sh_addr); \ uint ## B ## _t memsz = EGET(text->sh_size); \ Elf ## B ## _Rel *rel; \ Elf ## B ## _Rela *rela; \ /* search the section headers for relocations */ \ for (s = 0; s < EGET(ehdr->e_shnum); ++s) { \ uint32_t sh_type = EGET(shdr[s].sh_type); \ if (sh_type == SHT_REL) { \ rel = REL ## B (elf->data + EGET(shdr[s].sh_offset)); \ rela = NULL; \ rmax = EGET(shdr[s].sh_size) / sizeof(*rel); \ } else if (sh_type == SHT_RELA) { \ rel = NULL; \ rela = RELA ## B (elf->data + EGET(shdr[s].sh_offset)); \ rmax = EGET(shdr[s].sh_size) / sizeof(*rela); \ } else \ continue; \ /* now see if any of the relocs are in the .text */ \ for (r = 0; r < rmax; ++r) { \ unsigned long sym_max; \ Elf ## B ## _Addr offset_tmp; \ Elf ## B ## _Sym *func; \ Elf ## B ## _Sym *sym; \ Elf ## B ## _Addr r_offset; \ uint ## B ## _t r_info; \ if (sh_type == SHT_REL) { \ r_offset = EGET(rel[r].r_offset); \ r_info = EGET(rel[r].r_info); \ } else { \ r_offset = EGET(rela[r].r_offset); \ r_info = EGET(rela[r].r_info); \ } \ /* make sure this relocation is inside of the .text */ \ if (r_offset < vaddr || r_offset >= vaddr + memsz) { \ if (be_verbose <= 2) continue; \ } else \ *found_textrels = 1; \ /* locate this relocation symbol name */ \ sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \ if ((void*)sym > (void*)elf->data_end) { \ warn("%s: corrupt ELF symbol", elf->filename); \ continue; \ } \ sym_max = ELF ## B ## _R_SYM(r_info); \ if (sym_max * EGET(symtab->sh_entsize) < symtab->sh_size) \ sym += sym_max; \ else \ sym = NULL; \ sym_max = EGET(symtab->sh_size) / EGET(symtab->sh_entsize); \ /* show the raw details about this reloc */ \ printf(" %s: ", elf->base_filename); \ if (sym && sym->st_name) \ printf("%s", (char*)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name))); \ else \ printf("(memory/data?)"); \ printf(" [0x%lX]", (unsigned long)r_offset); \ /* now try to find the closest symbol that this rel is probably in */ \ sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \ func = NULL; \ offset_tmp = 0; \ while (sym_max--) { \ if (EGET(sym->st_value) < r_offset && EGET(sym->st_value) > offset_tmp) { \ func = sym; \ offset_tmp = EGET(sym->st_value); \ } \ ++sym; \ } \ printf(" in "); \ if (func && func->st_name) { \ const char *func_name = elf->data + EGET(strtab->sh_offset) + EGET(func->st_name); \ if (r_offset > EGET(func->st_size)) \ printf("(optimized out: previous %s)", func_name); \ else \ printf("%s", func_name); \ } else \ printf("(optimized out)"); \ printf(" [0x%lX]\n", (unsigned long)offset_tmp); \ if (be_verbose && has_objdump) { \ char *sysbuf; \ size_t syslen; \ const char sysfmt[] = "objdump -r -R -d -w -l --start-address=0x%lX --stop-address=0x%lX %s | grep --color -i -C 3 '.*[[:space:]]%lX:[[:space:]]*R_.*'\n"; \ syslen = sizeof(sysfmt) + strlen(elf->filename) + 3 * sizeof(unsigned long) + 1; \ sysbuf = xmalloc(syslen); \ if (sysbuf) { \ Elf ## B ## _Addr end_addr = offset_tmp + EGET(func->st_size); \ if (end_addr < r_offset) \ /* not uncommon when things are optimized out */ \ end_addr = r_offset + 0x100; \ snprintf(sysbuf, syslen, sysfmt, \ (unsigned long)offset_tmp, \ (unsigned long)end_addr, \ elf->filename, \ (unsigned long)r_offset); \ fflush(stdout); \ system(sysbuf); \ fflush(stdout); \ free(sysbuf); \ } \ } \ } \ } } SHOW_TEXTRELS(32) SHOW_TEXTRELS(64) } if (!*found_textrels) warnf("ELF %s has TEXTREL markings but doesnt appear to have any real TEXTREL's !?", elf->filename); return NULL; } static void rpath_security_checks(elfobj *, char *, const char *); static void rpath_security_checks(elfobj *elf, char *item, const char *dt_type) { struct stat st; switch (*item) { case '/': break; case '.': warnf("Security problem with relative %s '%s' in %s", dt_type, item, elf->filename); break; case ':': case '\0': warnf("Security problem NULL %s in %s", dt_type, elf->filename); break; case '$': if (fstat(elf->fd, &st) != -1) if ((st.st_mode & S_ISUID) || (st.st_mode & S_ISGID)) warnf("Security problem with %s='%s' in %s with mode set of %o", dt_type, item, elf->filename, (unsigned int) st.st_mode & 07777); break; default: warnf("Maybe? sec problem with %s='%s' in %s", dt_type, item, elf->filename); break; } } static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len) { unsigned long i, s; char *rpath, *runpath, **r; void *strtbl_void; if (!show_rpath) return; strtbl_void = elf_findsecbyname(elf, ".dynstr"); rpath = runpath = NULL; if (elf->phdr && strtbl_void) { #define SHOW_RPATH(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Dyn *dyn; \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \ Elf ## B ## _Off offset; \ Elf ## B ## _Xword word; \ /* Scan all the program headers */ \ for (i = 0; i < EGET(ehdr->e_phnum); i++) { \ /* Just scan dynamic headers */ \ if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \ offset = EGET(phdr[i].p_offset); \ if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \ /* Just scan dynamic RPATH/RUNPATH headers */ \ dyn = DYN ## B (elf->data + offset); \ while ((word=EGET(dyn->d_tag)) != DT_NULL) { \ if (word == DT_RPATH) { \ r = &rpath; \ } else if (word == DT_RUNPATH) { \ r = &runpath; \ } else { \ ++dyn; \ continue; \ } \ /* Verify the memory is somewhat sane */ \ offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \ if (offset < (Elf ## B ## _Off)elf->len) { \ if (*r) warn("ELF has multiple %s's !?", get_elfdtype(word)); \ *r = (char*)(elf->data + offset); \ /* cache the length in case we need to nuke this section later on */ \ if (fix_elf) \ offset = strlen(*r); \ /* If quiet, don't output paths in ld.so.conf */ \ if (be_quiet) { \ size_t len; \ char *start, *end; \ /* note that we only 'chop' off leading known paths. */ \ /* since *r is read-only memory, we can only move the ptr forward. */ \ start = *r; \ /* scan each path in : delimited list */ \ while (start) { \ rpath_security_checks(elf, start, get_elfdtype(word)); \ end = strchr(start, ':'); \ len = (end ? abs(end - start) : strlen(start)); \ if (use_ldcache) \ for (s = 0; ldpaths[s]; ++s) \ if (!strncmp(ldpaths[s], start, len) && !ldpaths[s][len]) { \ *r = end; \ /* corner case ... if RPATH reads "/usr/lib:", we want \ * to show ':' rather than '' */ \ if (end && end[1] != '\0') \ (*r)++; \ break; \ } \ if (!*r || !end) \ break; \ else \ start = start + len + 1; \ } \ } \ if (*r) { \ if (fix_elf > 2 || (fix_elf && **r == '\0')) { \ /* just nuke it */ \ nuke_it##B: \ memset(*r, 0x00, offset); \ *r = NULL; \ ESET(dyn->d_tag, DT_DEBUG); \ ESET(dyn->d_un.d_ptr, 0); \ } else if (fix_elf) { \ /* try to clean "bad" paths */ \ size_t len, tmpdir_len; \ char *start, *end; \ const char *tmpdir; \ start = *r; \ tmpdir = (getenv("TMPDIR") ? : "."); \ tmpdir_len = strlen(tmpdir); \ while (1) { \ end = strchr(start, ':'); \ if (start == end) { \ eat_this_path##B: \ len = strlen(end); \ memmove(start, end+1, len); \ start[len-1] = '\0'; \ end = start - 1; \ } else if (tmpdir && !strncmp(start, tmpdir, tmpdir_len)) { \ if (!end) { \ if (start == *r) \ goto nuke_it##B; \ *--start = '\0'; \ } else \ goto eat_this_path##B; \ } \ if (!end) \ break; \ start = end + 1; \ } \ if (**r == '\0') \ goto nuke_it##B; \ } \ if (*r) \ *found_rpath = 1; \ } \ } \ ++dyn; \ } \ } } SHOW_RPATH(32) SHOW_RPATH(64) } if (be_wewy_wewy_quiet) return; if (rpath && runpath) { if (!strcmp(rpath, runpath)) { xstrcat(ret, runpath, ret_len); } else { fprintf(stderr, "RPATH [%s] != RUNPATH [%s]\n", rpath, runpath); xchrcat(ret, '{', ret_len); xstrcat(ret, rpath, ret_len); xchrcat(ret, ',', ret_len); xstrcat(ret, runpath, ret_len); xchrcat(ret, '}', ret_len); } } else if (rpath || runpath) xstrcat(ret, (runpath ? runpath : rpath), ret_len); else if (!be_quiet) xstrcat(ret, " - ", ret_len); } #define LDSO_CACHE_MAGIC "ld.so-" #define LDSO_CACHE_MAGIC_LEN (sizeof LDSO_CACHE_MAGIC -1) #define LDSO_CACHE_VER "1.7.0" #define LDSO_CACHE_VER_LEN (sizeof LDSO_CACHE_VER -1) #define FLAG_ANY -1 #define FLAG_TYPE_MASK 0x00ff #define FLAG_LIBC4 0x0000 #define FLAG_ELF 0x0001 #define FLAG_ELF_LIBC5 0x0002 #define FLAG_ELF_LIBC6 0x0003 #define FLAG_REQUIRED_MASK 0xff00 #define FLAG_SPARC_LIB64 0x0100 #define FLAG_IA64_LIB64 0x0200 #define FLAG_X8664_LIB64 0x0300 #define FLAG_S390_LIB64 0x0400 #define FLAG_POWERPC_LIB64 0x0500 #define FLAG_MIPS64_LIBN32 0x0600 #define FLAG_MIPS64_LIBN64 0x0700 static char *lookup_cache_lib(elfobj *, char *); #if defined(__GLIBC__) || defined(__UCLIBC__) static char *lookup_cache_lib(elfobj *elf, char *fname) { int fd = 0; char *strs; static char buf[__PAX_UTILS_PATH_MAX] = ""; const char *cachefile = "/etc/ld.so.cache"; struct stat st; typedef struct { char magic[LDSO_CACHE_MAGIC_LEN]; char version[LDSO_CACHE_VER_LEN]; int nlibs; } header_t; header_t *header; typedef struct { int flags; int sooffset; int liboffset; } libentry_t; libentry_t *libent; if (fname == NULL) return NULL; if (ldcache == 0) { if (stat(cachefile, &st) || (fd = open(cachefile, O_RDONLY)) == -1) return NULL; /* cache these values so we only map/unmap the cache file once */ ldcache_size = st.st_size; ldcache = mmap(0, ldcache_size, PROT_READ, MAP_SHARED, fd, 0); close(fd); if (ldcache == (caddr_t)-1) { ldcache = 0; return NULL; } if (memcmp(((header_t *) ldcache)->magic, LDSO_CACHE_MAGIC, LDSO_CACHE_MAGIC_LEN)) return NULL; if (memcmp (((header_t *) ldcache)->version, LDSO_CACHE_VER, LDSO_CACHE_VER_LEN)) return NULL; } header = (header_t *) ldcache; libent = (libentry_t *) (ldcache + sizeof(header_t)); strs = (char *) &libent[header->nlibs]; for (fd = 0; fd < header->nlibs; fd++) { /* this should be more fine grained, but for now we assume that * diff arches will not be cached together. and we ignore the * the different multilib mips cases. */ if (elf->elf_class == ELFCLASS64 && !(libent[fd].flags & FLAG_REQUIRED_MASK)) continue; if (elf->elf_class == ELFCLASS32 && (libent[fd].flags & FLAG_REQUIRED_MASK)) continue; if (strcmp(fname, strs + libent[fd].sooffset) != 0) continue; strncpy(buf, strs + libent[fd].liboffset, sizeof(buf)); } return buf; } #elif defined(__NetBSD__) static char *lookup_cache_lib(elfobj *elf, char *fname) { static char buf[__PAX_UTILS_PATH_MAX] = ""; static struct stat st; char **ldpath; for (ldpath = ldpaths; *ldpath != NULL; ldpath++) { if ((unsigned) snprintf(buf, sizeof(buf), "%s/%s", *ldpath, fname) >= sizeof(buf)) continue; /* if the pathname is too long, or something went wrong, ignore */ if (stat(buf, &st) != 0) continue; /* if the lib doesn't exist in *ldpath, look further */ /* NetBSD doesn't actually do sanity checks, it just loads the file * and if that doesn't work, continues looking in other directories. * This cannot easily be safely emulated, unfortunately. For now, * just assume that if it exists, it's a valid library. */ return buf; } /* not found in any path */ return NULL; } #else #warning Cache support not implemented for your target static char *lookup_cache_lib(elfobj *elf, char *fname) { return NULL; } #endif static const char *scanelf_file_needed_lib(elfobj *elf, char *found_needed, char *found_lib, int op, char **ret, size_t *ret_len) { unsigned long i; char *needed; void *strtbl_void; char *p; if ((op==0 && !show_needed) || (op==1 && !find_lib)) return NULL; strtbl_void = elf_findsecbyname(elf, ".dynstr"); if (elf->phdr && strtbl_void) { #define SHOW_NEEDED(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Dyn *dyn; \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \ Elf ## B ## _Off offset; \ for (i = 0; i < EGET(ehdr->e_phnum); i++) { \ if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \ offset = EGET(phdr[i].p_offset); \ if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \ dyn = DYN ## B (elf->data + offset); \ while (EGET(dyn->d_tag) != DT_NULL) { \ if (EGET(dyn->d_tag) == DT_NEEDED) { \ offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \ if (offset >= (Elf ## B ## _Off)elf->len) { \ ++dyn; \ continue; \ } \ needed = (char*)(elf->data + offset); \ if (op == 0) { \ if (!be_wewy_wewy_quiet) { \ if (*found_needed) xchrcat(ret, ',', ret_len); \ if (use_ldcache) \ if ((p = lookup_cache_lib(elf, needed)) != NULL) \ needed = p; \ xstrcat(ret, needed, ret_len); \ } \ *found_needed = 1; \ } else { \ if (!strncmp(find_lib, needed, strlen( !g_match ? needed : find_lib))) { \ *found_lib = 1; \ return (be_wewy_wewy_quiet ? NULL : needed); \ } \ } \ } \ ++dyn; \ } \ } } SHOW_NEEDED(32) SHOW_NEEDED(64) if (op == 0 && !*found_needed && be_verbose) warn("ELF lacks DT_NEEDED sections: %s", elf->filename); } return NULL; } static char *scanelf_file_interp(elfobj *elf, char *found_interp) { void *strtbl_void; if (!show_interp) return NULL; strtbl_void = elf_findsecbyname(elf, ".interp"); if (strtbl_void) { #define SHOW_INTERP(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \ *found_interp = 1; \ return (be_wewy_wewy_quiet ? NULL : elf->data + EGET(strtbl->sh_offset)); \ } SHOW_INTERP(32) SHOW_INTERP(64) } return NULL; } static char *scanelf_file_bind(elfobj *elf, char *found_bind) { unsigned long i; struct stat s; char dynamic = 0; if (!show_bind) return NULL; if (!elf->phdr) return NULL; #define SHOW_BIND(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Dyn *dyn; \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ Elf ## B ## _Off offset; \ for (i = 0; i < EGET(ehdr->e_phnum); i++) { \ if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \ dynamic = 1; \ offset = EGET(phdr[i].p_offset); \ if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \ dyn = DYN ## B (elf->data + offset); \ while (EGET(dyn->d_tag) != DT_NULL) { \ if (EGET(dyn->d_tag) == DT_BIND_NOW || \ (EGET(dyn->d_tag) == DT_FLAGS && EGET(dyn->d_un.d_val) & DF_BIND_NOW)) \ { \ if (be_quiet) return NULL; \ *found_bind = 1; \ return (char *)(be_wewy_wewy_quiet ? NULL : "NOW"); \ } \ ++dyn; \ } \ } \ } SHOW_BIND(32) SHOW_BIND(64) if (be_wewy_wewy_quiet) return NULL; /* don't output anything if quiet mode and the ELF is static or not setuid */ if (be_quiet && (!dynamic || (!fstat(elf->fd, &s) && !(s.st_mode & (S_ISUID|S_ISGID))))) { return NULL; } else { *found_bind = 1; return (char *) (dynamic ? "LAZY" : "STATIC"); } } static char *scanelf_file_soname(elfobj *elf, char *found_soname) { unsigned long i; char *soname; void *strtbl_void; if (!show_soname) return NULL; strtbl_void = elf_findsecbyname(elf, ".dynstr"); if (elf->phdr && strtbl_void) { #define SHOW_SONAME(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Dyn *dyn; \ Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \ Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \ Elf ## B ## _Shdr *strtbl = SHDR ## B (strtbl_void); \ Elf ## B ## _Off offset; \ /* only look for soname in shared objects */ \ if (ehdr->e_type != ET_DYN) \ return NULL; \ for (i = 0; i < EGET(ehdr->e_phnum); i++) { \ if (EGET(phdr[i].p_type) != PT_DYNAMIC) continue; \ offset = EGET(phdr[i].p_offset); \ if (offset >= elf->len - sizeof(Elf ## B ## _Dyn)) continue; \ dyn = DYN ## B (elf->data + offset); \ while (EGET(dyn->d_tag) != DT_NULL) { \ if (EGET(dyn->d_tag) == DT_SONAME) { \ offset = EGET(strtbl->sh_offset) + EGET(dyn->d_un.d_ptr); \ if (offset >= (Elf ## B ## _Off)elf->len) { \ ++dyn; \ continue; \ } \ soname = (char*)(elf->data + offset); \ *found_soname = 1; \ return (be_wewy_wewy_quiet ? NULL : soname); \ } \ ++dyn; \ } \ } } SHOW_SONAME(32) SHOW_SONAME(64) } return NULL; } static char *scanelf_file_sym(elfobj *elf, char *found_sym) { unsigned long i; char *ret; void *symtab_void, *strtab_void; if (!find_sym) return NULL; ret = find_sym; scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void); if (symtab_void && strtab_void) { #define FIND_SYM(B) \ if (elf->elf_class == ELFCLASS ## B) { \ Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \ Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \ Elf ## B ## _Sym *sym = SYM ## B (elf->data + EGET(symtab->sh_offset)); \ unsigned long cnt = EGET(symtab->sh_entsize); \ char *symname; \ if (cnt) \ cnt = EGET(symtab->sh_size) / cnt; \ for (i = 0; i < cnt; ++i) { \ if (sym->st_name) { \ /* make sure the symbol name is in acceptable memory range */ \ symname = (char *)(elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name)); \ if ((void*)symname > (void*)elf->data_end) { \ warnf("%s: corrupt ELF symbols", elf->filename); \ ++sym; \ continue; \ } \ /* debug display ... show all symbols and some extra info */ \ if (g_match ? rematch(ret, symname, REG_EXTENDED) == 0 : *ret == '*') { \ printf("%s(%s) %5lX %15s %s\n", \ ((*found_sym == 0) ? "\n\t" : "\t"), \ elf->base_filename, \ (unsigned long)sym->st_size, \ get_elfstttype(sym->st_info), \ symname); \ *found_sym = 1; \ } else { \ /* allow the user to specify a comma delimited list of symbols to search for */ \ char *this_sym, *this_sym_ver, *next_sym; \ this_sym = ret; \ this_sym_ver = versioned_symname; \ do { \ next_sym = strchr(this_sym, ','); \ if (next_sym == NULL) \ next_sym = this_sym + strlen(this_sym); \ /* do we want a defined symbol ? */ \ if (*this_sym == '+') { \ if (sym->st_shndx == SHN_UNDEF) \ goto skip_this_sym##B; \ ++this_sym; \ ++this_sym_ver; \ /* do we want an undefined symbol ? */ \ } else if (*this_sym == '-') { \ if (sym->st_shndx != SHN_UNDEF) \ goto skip_this_sym##B; \ ++this_sym; \ ++this_sym_ver; \ } \ /* ok, lets compare the name now */ \ if ((strncmp(this_sym, symname, (next_sym-this_sym)) == 0 && symname[next_sym-this_sym] == '\0') || \ (strncmp(this_sym_ver, symname, strlen(this_sym_ver)) == 0)) { \ if (be_semi_verbose) { \ char buf[126]; \ snprintf(buf, sizeof(buf), "%lX %s %s", \ (unsigned long)sym->st_size, get_elfstttype(sym->st_info), this_sym); \ ret = buf; \ } else \ ret = this_sym; \ (*found_sym)++; \ goto break_out; \ } \ skip_this_sym##B: this_sym = next_sym + 1; \ } while (*next_sym != '\0'); \ } \ } \ ++sym; \ } } FIND_SYM(32) FIND_SYM(64) } break_out: if (be_wewy_wewy_quiet) return NULL; if (*find_sym != '*' && *found_sym) return ret; if (be_quiet) return NULL; else return (char *)" - "; } static char *scanelf_file_sections(elfobj *elf, char *found_section) { if (!find_section) return NULL; #define FIND_SECTION(B) \ if (elf->elf_class == ELFCLASS ## B) { \ int invert; \ Elf ## B ## _Shdr *section; \ invert = (*find_section == '!' ? 1 : 0); \ section = SHDR ## B (elf_findsecbyname(elf, find_section+invert)); \ if ((section == NULL && invert) || (section != NULL && !invert)) \ *found_section = 1; \ } FIND_SECTION(32) FIND_SECTION(64) if (be_wewy_wewy_quiet) return NULL; if (*found_section) return find_section; if (be_quiet) return NULL; else return (char *)" - "; } /* scan an elf file and show all the fun stuff */ #define prints(str) write(fileno(stdout), str, strlen(str)) static int scanelf_elfobj(elfobj *elf) { unsigned long i; char found_pax, found_phdr, found_relro, found_load, found_textrel, found_rpath, found_needed, found_interp, found_bind, found_soname, found_sym, found_lib, found_file, found_textrels, found_section; static char *out_buffer = NULL; static size_t out_len; found_pax = found_phdr = found_relro = found_load = found_textrel = \ found_rpath = found_needed = found_interp = found_bind = found_soname = \ found_sym = found_lib = found_file = found_textrels = found_section = 0; if (be_verbose > 2) printf("%s: scanning file {%s,%s}\n", elf->filename, get_elfeitype(EI_CLASS, elf->elf_class), get_elfeitype(EI_DATA, elf->data[EI_DATA])); else if (be_verbose > 1) printf("%s: scanning file\n", elf->filename); /* init output buffer */ if (!out_buffer) { out_len = sizeof(char) * 80; out_buffer = (char*)xmalloc(out_len); } *out_buffer = '\0'; /* show the header */ if (!be_quiet && show_banner) { for (i = 0; out_format[i]; ++i) { if (!IS_MODIFIER(out_format[i])) continue; switch (out_format[++i]) { case '+': break; case '%': break; case '#': break; case 'F': case 'p': case 'f': prints("FILE "); found_file = 1; break; case 'o': prints(" TYPE "); break; case 'x': prints(" PAX "); break; case 'e': prints("STK/REL/PTL "); break; case 't': prints("TEXTREL "); break; case 'r': prints("RPATH "); break; case 'M': prints("CLASS "); break; case 'n': prints("NEEDED "); break; case 'i': prints("INTERP "); break; case 'b': prints("BIND "); break; case 'S': prints("SONAME "); break; case 's': prints("SYM "); break; case 'N': prints("LIB "); break; case 'T': prints("TEXTRELS "); break; case 'k': prints("SECTION "); break; case 'a': prints("ARCH "); break; default: warnf("'%c' has no title ?", out_format[i]); } } if (!found_file) prints("FILE "); prints("\n"); found_file = 0; show_banner = 0; } /* dump all the good stuff */ for (i = 0; out_format[i]; ++i) { const char *out; const char *tmp; if (!IS_MODIFIER(out_format[i])) { xchrcat(&out_buffer, out_format[i], &out_len); continue; } out = NULL; be_wewy_wewy_quiet = (out_format[i] == '#'); be_semi_verbose = (out_format[i] == '+'); switch (out_format[++i]) { case '+': case '%': case '#': xchrcat(&out_buffer, out_format[i], &out_len); break; case 'F': found_file = 1; if (be_wewy_wewy_quiet) break; xstrcat(&out_buffer, elf->filename, &out_len); break; case 'p': found_file = 1; if (be_wewy_wewy_quiet) break; tmp = elf->filename; if (search_path) { ssize_t len_search = strlen(search_path); ssize_t len_file = strlen(elf->filename); if (!strncmp(elf->filename, search_path, len_search) && \ len_file > len_search) tmp += len_search; if (*tmp == '/' && search_path[len_search-1] == '/') tmp++; } xstrcat(&out_buffer, tmp, &out_len); break; case 'f': found_file = 1; if (be_wewy_wewy_quiet) break; tmp = strrchr(elf->filename, '/'); tmp = (tmp == NULL ? elf->filename : tmp+1); xstrcat(&out_buffer, tmp, &out_len); break; case 'o': out = get_elfetype(elf); break; case 'x': out = scanelf_file_pax(elf, &found_pax); break; case 'e': out = scanelf_file_phdr(elf, &found_phdr, &found_relro, &found_load); break; case 't': out = scanelf_file_textrel(elf, &found_textrel); break; case 'T': out = scanelf_file_textrels(elf, &found_textrels, &found_textrel); break; case 'r': scanelf_file_rpath(elf, &found_rpath, &out_buffer, &out_len); break; case 'M': out = get_elfeitype(EI_CLASS, elf->data[EI_CLASS]); break; case 'n': case 'N': out = scanelf_file_needed_lib(elf, &found_needed, &found_lib, (out_format[i]=='N'), &out_buffer, &out_len); break; case 'i': out = scanelf_file_interp(elf, &found_interp); break; case 'b': out = scanelf_file_bind(elf, &found_bind); break; case 'S': out = scanelf_file_soname(elf, &found_soname); break; case 's': out = scanelf_file_sym(elf, &found_sym); break; case 'k': out = scanelf_file_sections(elf, &found_section); break; case 'a': out = get_elfemtype(elf); break; default: warnf("'%c' has no scan code?", out_format[i]); } if (out) { /* hack for comma delimited output like `scanelf -s sym1,sym2,sym3` */ if (out_format[i] == 's' && (tmp=strchr(out,',')) != NULL) xstrncat(&out_buffer, out, &out_len, (tmp-out)); else xstrcat(&out_buffer, out, &out_len); } } #define FOUND_SOMETHING() \ (found_pax || found_phdr || found_relro || found_load || found_textrel || \ found_rpath || found_needed || found_interp || found_bind || \ found_soname || found_sym || found_lib || found_textrels || found_section ) if (!found_file && (!be_quiet || (be_quiet && FOUND_SOMETHING()))) { xchrcat(&out_buffer, ' ', &out_len); xstrcat(&out_buffer, elf->filename, &out_len); } if (!be_quiet || (be_quiet && FOUND_SOMETHING())) { puts(out_buffer); fflush(stdout); } return 0; } /* scan a single elf */ static int scanelf_elf(const char *filename, int fd, size_t len) { int ret = 1; elfobj *elf; /* verify this is real ELF */ if ((elf = _readelf_fd(filename, fd, len, !fix_elf)) == NULL) { if (be_verbose > 2) printf("%s: not an ELF\n", filename); return ret; } switch (match_bits) { case 32: if (elf->elf_class != ELFCLASS32) goto label_done; break; case 64: if (elf->elf_class != ELFCLASS64) goto label_done; break; default: break; } if (strlen(match_etypes)) { char sbuf[126]; strncpy(sbuf, match_etypes, sizeof(sbuf)); if (strchr(match_etypes, ',') != NULL) { char *p; while((p = strrchr(sbuf, ',')) != NULL) { *p = 0; if (etype_lookup(p+1) == get_etype(elf)) goto label_ret; } } if (etype_lookup(sbuf) != get_etype(elf)) goto label_done; } label_ret: ret = scanelf_elfobj(elf); label_done: unreadelf(elf); return ret; } /* scan an archive of elfs */ static int scanelf_archive(const char *filename, int fd, size_t len) { archive_handle *ar; archive_member *m; char *ar_buffer; elfobj *elf; ar = ar_open_fd(filename, fd); if (ar == NULL) return 1; ar_buffer = (char*)mmap(0, len, PROT_READ | (fix_elf ? PROT_WRITE : 0), (fix_elf ? MAP_SHARED : MAP_PRIVATE), fd, 0); while ((m=ar_next(ar)) != NULL) { elf = readelf_buffer(m->name, ar_buffer+lseek(fd,0,SEEK_CUR), m->size); if (elf) { scanelf_elfobj(elf); unreadelf(elf); } } munmap(ar_buffer, len); return 0; } /* scan a file which may be an elf or an archive or some other magical beast */ static int scanelf_file(const char *filename, const struct stat *st_cache) { const struct stat *st = st_cache; struct stat symlink_st; int fd; /* always handle regular files and handle symlinked files if no -y */ if (S_ISLNK(st->st_mode)) { if (!scan_symlink) return 1; stat(filename, &symlink_st); st = &symlink_st; } if (!S_ISREG(st->st_mode)) { if (be_verbose > 2) printf("%s: skipping non-file\n", filename); return 1; } if ((fd=open(filename, (fix_elf ? O_RDWR : O_RDONLY))) == -1) return 1; if (scanelf_elf(filename, fd, st->st_size) == 1 && scan_archives) /* if it isn't an ELF, maybe it's an .a archive */ scanelf_archive(filename, fd, st->st_size); close(fd); return 0; } /* scan a directory for ET_EXEC files and print when we find one */ static int scanelf_dir(const char *path) { register DIR *dir; register struct dirent *dentry; struct stat st_top, st; char buf[__PAX_UTILS_PATH_MAX]; size_t pathlen = 0, len = 0; int ret = 0; /* make sure path exists */ if (lstat(path, &st_top) == -1) { if (be_verbose > 2) printf("%s: does not exist\n", path); return 1; } /* ok, if it isn't a directory, assume we can open it */ if (!S_ISDIR(st_top.st_mode)) { return scanelf_file(path, &st_top); } /* now scan the dir looking for fun stuff */ if ((dir = opendir(path)) == NULL) { warnf("could not opendir %s: %s", path, strerror(errno)); return 1; } if (be_verbose > 1) printf("%s: scanning dir\n", path); pathlen = strlen(path); while ((dentry = readdir(dir))) { if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, "..")) continue; len = (pathlen + 1 + strlen(dentry->d_name) + 1); if (len >= sizeof(buf)) { warnf("Skipping '%s': len > sizeof(buf); %lu > %lu\n", path, (unsigned long)len, (unsigned long)sizeof(buf)); continue; } snprintf(buf, sizeof(buf), "%s%s%s", path, (path[pathlen-1] == '/') ? "" : "/", dentry->d_name); if (lstat(buf, &st) != -1) { if (S_ISREG(st.st_mode)) ret = scanelf_file(buf, &st); else if (dir_recurse && S_ISDIR(st.st_mode)) { if (dir_crossmount || (st_top.st_dev == st.st_dev)) ret = scanelf_dir(buf); } } } closedir(dir); return ret; } static int scanelf_from_file(const char *filename) { FILE *fp = NULL; char *p; char path[__PAX_UTILS_PATH_MAX]; int ret = 0; if (strcmp(filename, "-") == 0) fp = stdin; else if ((fp = fopen(filename, "r")) == NULL) return 1; while ((fgets(path, __PAX_UTILS_PATH_MAX, fp)) != NULL) { if ((p = strchr(path, '\n')) != NULL) *p = 0; search_path = path; ret = scanelf_dir(path); } if (fp != stdin) fclose(fp); return ret; } #if defined(__GLIBC__) || defined(__UCLIBC__) || defined(__NetBSD__) static int load_ld_cache_config(int i, const char *fname) { FILE *fp = NULL; char *p; char path[__PAX_UTILS_PATH_MAX]; if (i + 1 == ARRAY_SIZE(ldpaths)) return i; if ((fp = fopen(fname, "r")) == NULL) return i; while ((fgets(path, __PAX_UTILS_PATH_MAX, fp)) != NULL) { if ((p = strrchr(path, '\r')) != NULL) *p = 0; if ((p = strchr(path, '\n')) != NULL) *p = 0; #ifdef __linux__ // recursive includes of the same file will make this segfault. if ((memcmp(path, "include", 7) == 0) && isblank(path[7])) { glob64_t gl; size_t x; char gpath[__PAX_UTILS_PATH_MAX]; memset(gpath, 0, sizeof(gpath)); if (path[8] != '/') snprintf(gpath, sizeof(gpath), "/etc/%s", &path[8]); else strncpy(gpath, &path[8], sizeof(gpath)); if ((glob64(gpath, 0, NULL, &gl)) == 0) { for (x = 0; x < gl.gl_pathc; ++x) { /* try to avoid direct loops */ if (strcmp(gl.gl_pathv[x], fname) == 0) continue; i = load_ld_cache_config(i, gl.gl_pathv[x]); if (i + 1 >= ARRAY_SIZE(ldpaths)) { globfree64(&gl); return i; } } globfree64 (&gl); continue; } } #endif if (*path != '/') continue; ldpaths[i++] = xstrdup(path); if (i + 1 == ARRAY_SIZE(ldpaths)) break; } ldpaths[i] = NULL; fclose(fp); return i; } #elif defined(__FreeBSD__) || (__DragonFly__) static int load_ld_cache_config(int i, const char *fname) { FILE *fp = NULL; char *b = NULL, *p; struct elfhints_hdr hdr; if (i + 1 == ARRAY_SIZE(ldpaths)) return i; if ((fp = fopen(fname, "r")) == NULL) return i; if (fread(&hdr, 1, sizeof(hdr), fp) != sizeof(hdr) || hdr.magic != ELFHINTS_MAGIC || hdr.version != 1 || fseek(fp, hdr.strtab + hdr.dirlist, SEEK_SET) == -1) { fclose(fp); return i; } b = (char*)malloc(hdr.dirlistlen+1); if (fread(b, 1, hdr.dirlistlen+1, fp) != hdr.dirlistlen+1) { fclose(fp); free(b); return i; } while ((p = strsep(&b, ":"))) { if (*p == '\0') continue; ldpaths[i++] = xstrdup(p); if (i + 1 == ARRAY_SIZE(ldpaths)) break; } ldpaths[i] = NULL; free(b); fclose(fp); return i; } #else #warning Cache config support not implemented for your target static int load_ld_cache_config(int i, const char *fname) { memset(ldpaths, 0x00, sizeof(ldpaths)); } #endif /* scan /etc/ld.so.conf for paths */ static void scanelf_ldpath() { char scan_l, scan_ul, scan_ull; int i = 0; if (!ldpaths[0]) err("Unable to load any paths from ld.so.conf"); scan_l = scan_ul = scan_ull = 0; while (ldpaths[i]) { if (!scan_l && !strcmp(ldpaths[i], "/lib")) scan_l = 1; if (!scan_ul && !strcmp(ldpaths[i], "/usr/lib")) scan_ul = 1; if (!scan_ull && !strcmp(ldpaths[i], "/usr/local/lib")) scan_ull = 1; scanelf_dir(ldpaths[i]); ++i; } if (!scan_l) scanelf_dir("/lib"); if (!scan_ul) scanelf_dir("/usr/lib"); if (!scan_ull) scanelf_dir("/usr/local/lib"); } /* scan env PATH for paths */ static void scanelf_envpath() { char *path, *p; path = getenv("PATH"); if (!path) err("PATH is not set in your env !"); path = xstrdup(path); while ((p = strrchr(path, ':')) != NULL) { scanelf_dir(p + 1); *p = 0; } free(path); } /* usage / invocation handling functions */ #define PARSE_FLAGS "plRmyAXz:xetrnLibSs:k:gN:TaqvF:f:o:E:M:BhV" #define a_argument required_argument static struct option const long_opts[] = { {"path", no_argument, NULL, 'p'}, {"ldpath", no_argument, NULL, 'l'}, {"recursive", no_argument, NULL, 'R'}, {"mount", no_argument, NULL, 'm'}, {"symlink", no_argument, NULL, 'y'}, {"archives", no_argument, NULL, 'A'}, {"ldcache", no_argument, NULL, 'L'}, {"fix", no_argument, NULL, 'X'}, {"setpax", a_argument, NULL, 'z'}, {"pax", no_argument, NULL, 'x'}, {"header", no_argument, NULL, 'e'}, {"textrel", no_argument, NULL, 't'}, {"rpath", no_argument, NULL, 'r'}, {"needed", no_argument, NULL, 'n'}, {"interp", no_argument, NULL, 'i'}, {"bind", no_argument, NULL, 'b'}, {"soname", no_argument, NULL, 'S'}, {"symbol", a_argument, NULL, 's'}, {"section", a_argument, NULL, 'k'}, {"lib", a_argument, NULL, 'N'}, {"gmatch", no_argument, NULL, 'g'}, {"textrels", no_argument, NULL, 'T'}, {"etype", a_argument, NULL, 'E'}, {"bits", a_argument, NULL, 'M'}, {"all", no_argument, NULL, 'a'}, {"quiet", no_argument, NULL, 'q'}, {"verbose", no_argument, NULL, 'v'}, {"format", a_argument, NULL, 'F'}, {"from", a_argument, NULL, 'f'}, {"file", a_argument, NULL, 'o'}, {"nobanner", no_argument, NULL, 'B'}, {"help", no_argument, NULL, 'h'}, {"version", no_argument, NULL, 'V'}, {NULL, no_argument, NULL, 0x0} }; static const char *opts_help[] = { "Scan all directories in PATH environment", "Scan all directories in /etc/ld.so.conf", "Scan directories recursively", "Don't recursively cross mount points", "Don't scan symlinks", "Scan archives (.a files)", "Utilize ld.so.cache information (use with -r/-n)", "Try and 'fix' bad things (use with -r/-e)", "Sets EI_PAX/PT_PAX_FLAGS to (use with -Xx)\n", "Print PaX markings", "Print GNU_STACK/PT_LOAD markings", "Print TEXTREL information", "Print RPATH information", "Print NEEDED information", "Print INTERP information", "Print BIND information", "Print SONAME information", "Find a specified symbol", "Find a specified section", "Find a specified library", "Use strncmp to match libraries. (use with -N)", "Locate cause of TEXTREL", "Print only ELF files matching etype ET_DYN,ET_EXEC ...", "Print only ELF files matching numeric bits", "Print all scanned info (-x -e -t -r -b)\n", "Only output 'bad' things", "Be verbose (can be specified more than once)", "Use specified format for output", "Read input stream from a filename", "Write output stream to a filename", "Don't display the header", "Print this help and exit", "Print version and exit", NULL }; /* display usage and exit */ static void usage(int status) { unsigned long i; printf("* Scan ELF binaries for stuff\n\n" "Usage: %s [options] [dir2 dirN file2 fileN ...]\n\n", argv0); printf("Options: -[%s]\n", PARSE_FLAGS); for (i = 0; long_opts[i].name; ++i) if (long_opts[i].has_arg == no_argument) printf(" -%c, --%-14s* %s\n", long_opts[i].val, long_opts[i].name, opts_help[i]); else printf(" -%c, --%-7s * %s\n", long_opts[i].val, long_opts[i].name, opts_help[i]); puts("\nFor more information, see the scanelf(1) manpage"); exit(status); } /* parse command line arguments and preform needed actions */ #define do_pax_state(option, flag) \ if (islower(option)) { \ flags &= ~PF_##flag; \ flags |= PF_NO##flag; \ } else { \ flags &= ~PF_NO##flag; \ flags |= PF_##flag; \ } static int parseargs(int argc, char *argv[]) { int i; const char *from_file = NULL; int ret = 0; opterr = 0; while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) { switch (i) { case 'V': printf("pax-utils-%s: %s compiled %s\n%s\n" "%s written for Gentoo by \n", VERSION, __FILE__, __DATE__, rcsid, argv0); exit(EXIT_SUCCESS); break; case 'h': usage(EXIT_SUCCESS); break; case 'f': if (from_file) warn("You prob don't want to specify -f twice"); from_file = optarg; break; case 'E': strncpy(match_etypes, optarg, sizeof(match_etypes)); break; case 'M': match_bits = atoi(optarg); break; case 'o': { if (freopen(optarg, "w", stdout) == NULL) err("Could not open output stream '%s': %s", optarg, strerror(errno)); break; } case 'k': if (find_section) warn("You prob don't want to specify -k twice"); find_section = optarg; break; case 's': { if (find_sym) warn("You prob don't want to specify -s twice"); find_sym = optarg; versioned_symname = (char*)xmalloc(sizeof(char) * (strlen(find_sym)+1+1)); sprintf(versioned_symname, "%s@", find_sym); break; } case 'N': { if (find_lib) warn("You prob don't want to specify -N twice"); find_lib = optarg; break; } case 'F': { if (out_format) warn("You prob don't want to specify -F twice"); out_format = optarg; break; } case 'z': { unsigned long flags = (PF_NOEMUTRAMP | PF_NORANDEXEC); size_t x; for (x = 0 ; x < strlen(optarg); x++) { switch(optarg[x]) { case 'p': case 'P': do_pax_state(optarg[x], PAGEEXEC); break; case 's': case 'S': do_pax_state(optarg[x], SEGMEXEC); break; case 'm': case 'M': do_pax_state(optarg[x], MPROTECT); break; case 'e': case 'E': do_pax_state(optarg[x], EMUTRAMP); break; case 'r': case 'R': do_pax_state(optarg[x], RANDMMAP); break; case 'x': case 'X': do_pax_state(optarg[x], RANDEXEC); break; default: break; } } if (!(((flags & PF_PAGEEXEC) && (flags & PF_NOPAGEEXEC)) || ((flags & PF_SEGMEXEC) && (flags & PF_NOSEGMEXEC)) || ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP)) || ((flags & PF_RANDEXEC) && (flags & PF_NORANDEXEC)) || ((flags & PF_EMUTRAMP) && (flags & PF_NOEMUTRAMP)) || ((flags & PF_RANDMMAP) && (flags & PF_NORANDMMAP)))) setpax = flags; break; } case 'g': g_match = 1; break; case 'L': use_ldcache = 1; break; case 'y': scan_symlink = 0; break; case 'A': scan_archives = 1; break; case 'B': show_banner = 0; break; case 'l': scan_ldpath = 1; break; case 'p': scan_envpath = 1; break; case 'R': dir_recurse = 1; break; case 'm': dir_crossmount = 0; break; case 'X': ++fix_elf; break; case 'x': show_pax = 1; break; case 'e': show_phdr = 1; break; case 't': show_textrel = 1; break; case 'r': show_rpath = 1; break; case 'n': show_needed = 1; break; case 'i': show_interp = 1; break; case 'b': show_bind = 1; break; case 'S': show_soname = 1; break; case 'T': show_textrels = 1; break; case 'q': be_quiet = 1; break; case 'v': be_verbose = (be_verbose % 20) + 1; break; case 'a': show_pax = show_phdr = show_textrel = show_rpath = show_bind = 1; break; case ':': err("Option '%c' is missing parameter", optopt); case '?': err("Unknown option '%c' or argument missing", optopt); default: err("Unhandled option '%c'; please report this", i); } } if (show_textrels && be_verbose) { if (which("objdump") != NULL) has_objdump = 1; } /* let the format option override all other options */ if (out_format) { show_pax = show_phdr = show_textrel = show_rpath = \ show_needed = show_interp = show_bind = show_soname = \ show_textrels = 0; for (i = 0; out_format[i]; ++i) { if (!IS_MODIFIER(out_format[i])) continue; switch (out_format[++i]) { case '+': break; case '%': break; case '#': break; case 'F': break; case 'p': break; case 'f': break; case 'k': break; case 's': break; case 'N': break; case 'o': break; case 'a': break; case 'M': break; case 'x': show_pax = 1; break; case 'e': show_phdr = 1; break; case 't': show_textrel = 1; break; case 'r': show_rpath = 1; break; case 'n': show_needed = 1; break; case 'i': show_interp = 1; break; case 'b': show_bind = 1; break; case 'S': show_soname = 1; break; case 'T': show_textrels = 1; break; default: err("Invalid format specifier '%c' (byte %i)", out_format[i], i+1); } } /* construct our default format */ } else { size_t fmt_len = 30; out_format = (char*)xmalloc(sizeof(char) * fmt_len); if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len); if (show_pax) xstrcat(&out_format, "%x ", &fmt_len); if (show_phdr) xstrcat(&out_format, "%e ", &fmt_len); if (show_textrel) xstrcat(&out_format, "%t ", &fmt_len); if (show_rpath) xstrcat(&out_format, "%r ", &fmt_len); if (show_needed) xstrcat(&out_format, "%n ", &fmt_len); if (show_interp) xstrcat(&out_format, "%i ", &fmt_len); if (show_bind) xstrcat(&out_format, "%b ", &fmt_len); if (show_soname) xstrcat(&out_format, "%S ", &fmt_len); if (show_textrels) xstrcat(&out_format, "%T ", &fmt_len); if (find_sym) xstrcat(&out_format, "%s ", &fmt_len); if (find_section) xstrcat(&out_format, "%k ", &fmt_len); if (find_lib) xstrcat(&out_format, "%N ", &fmt_len); if (!be_quiet) xstrcat(&out_format, "%F ", &fmt_len); } if (be_verbose > 2) printf("Format: %s\n", out_format); /* now lets actually do the scanning */ if (scan_ldpath || use_ldcache) load_ld_cache_config(0, __PAX_UTILS_DEFAULT_LD_CACHE_CONFIG); if (scan_ldpath) scanelf_ldpath(); if (scan_envpath) scanelf_envpath(); if (!from_file && optind == argc && ttyname(0) == NULL && !scan_ldpath && !scan_envpath) from_file = "-"; if (from_file) { scanelf_from_file(from_file); from_file = *argv; } if (optind == argc && !scan_ldpath && !scan_envpath && !from_file) err("Nothing to scan !?"); while (optind < argc) { search_path = argv[optind++]; ret = scanelf_dir(search_path); } /* clean up */ free(versioned_symname); for (i = 0; ldpaths[i]; ++i) free(ldpaths[i]); if (ldcache != 0) munmap(ldcache, ldcache_size); return ret; } static char **get_split_env(const char *envvar) { const char *delims = " \t\n"; char **envvals = NULL; char *env, *s; int nentry; if ((env = getenv(envvar)) == NULL) return NULL; env = xstrdup(env); if (env == NULL) return NULL; s = strtok(env, delims); if (s == NULL) { free(env); return NULL; } nentry = 0; while (s != NULL) { ++nentry; envvals = xrealloc(envvals, sizeof(*envvals) * (nentry+1)); envvals[nentry-1] = s; s = strtok(NULL, delims); } envvals[nentry] = NULL; /* don't want to free(env) as it contains the memory that backs * the envvals array of strings */ return envvals; } static void parseenv() { qa_textrels = get_split_env("QA_TEXTRELS"); qa_execstack = get_split_env("QA_EXECSTACK"); qa_wx_load = get_split_env("QA_WX_LOAD"); } #ifdef __PAX_UTILS_CLEANUP static void cleanup() { free(out_format); free(qa_textrels); free(qa_execstack); free(qa_wx_load); } #endif int main(int argc, char *argv[]) { int ret; if (argc < 2) usage(EXIT_FAILURE); parseenv(); ret = parseargs(argc, argv); fclose(stdout); #ifdef __PAX_UTILS_CLEANUP cleanup(); warn("The calls to add/delete heap should be off:\n" "\t- 1 due to the out_buffer not being freed in scanelf_file()\n" "\t- 1 per QA_TEXTRELS/QA_EXECSTACK/QA_WX_LOAD"); #endif return ret; } /* utility funcs */ static char *xstrdup(const char *s) { char *ret = strdup(s); if (!ret) err("Could not strdup(): %s", strerror(errno)); return ret; } static void *xmalloc(size_t size) { void *ret = malloc(size); if (!ret) err("Could not malloc() %li bytes", (unsigned long)size); return ret; } static void *xrealloc(void *ptr, size_t size) { void *ret = realloc(ptr, size); if (!ret) err("Could not realloc() %li bytes", (unsigned long)size); return ret; } static void xstrncat(char **dst, const char *src, size_t *curr_len, size_t n) { size_t new_len; new_len = strlen(*dst) + strlen(src); if (*curr_len <= new_len) { *curr_len = new_len + (*curr_len / 2); *dst = realloc(*dst, *curr_len); if (!*dst) err("could not realloc() %li bytes", (unsigned long)*curr_len); } if (n) strncat(*dst, src, n); else strcat(*dst, src); } static inline void xchrcat(char **dst, const char append, size_t *curr_len) { static char my_app[2]; my_app[0] = append; my_app[1] = '\0'; xstrcat(dst, my_app, curr_len); } /* Match filename against entries in matchlist, return TRUE * if the file is listed */ static int file_matches_list(const char *filename, char **matchlist) { char **file; char *match; char buf[__PAX_UTILS_PATH_MAX]; if (matchlist == NULL) return 0; for (file = matchlist; *file != NULL; file++) { if (search_path) { snprintf(buf, sizeof(buf), "%s%s", search_path, *file); match = buf; } else { match = *file; } if (fnmatch(match, filename, 0) == 0) return 1; } return 0; }