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/*
* Copyright 2003-2012 Gentoo Foundation
* Distributed under the terms of the GNU General Public License v2
*
* Copyright 2003-2012 Ned Ludd - <solar@gentoo.org>
* Copyright 2004-2012 Mike Frysinger - <vapier@gentoo.org>
*/
const char argv0[] = "scanelf";
#include "paxinc.h"
#define IS_MODIFIER(c) (c == '%' || c == '#' || c == '+')
/* prototypes */
static int file_matches_list(const char *filename, char **matchlist);
/* variables to control behavior */
static array_t _match_etypes = array_init_decl, *match_etypes = &_match_etypes;
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_perms = 0;
static char show_size = 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 show_endian = 0;
static char show_osabi = 0;
static char show_eabi = 0;
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;
static array_t _find_sym_arr = array_init_decl, *find_sym_arr = &_find_sym_arr;
static array_t _find_sym_regex_arr = array_init_decl, *find_sym_regex_arr = &_find_sym_regex_arr;
static char *find_lib = NULL;
static array_t _find_lib_arr = array_init_decl, *find_lib_arr = &_find_lib_arr;
static char *find_section = NULL;
static array_t _find_section_arr = array_init_decl, *find_section_arr = &_find_section_arr;
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 use_ldpath = 0;
static char **qa_textrels = NULL;
static char **qa_execstack = NULL;
static char **qa_wx_load = NULL;
static int match_bits = 0;
static unsigned int match_perms = 0;
static unsigned long setpax = 0UL;
static const char *objdump;
/* Boiler plate wrapper for expanding ELF macros for specific ELF sizes. */
#define _SCANELF_IF_ELF_SIZE(B, x) \
do { \
if (elf->elf_class == ELFCLASS ## B) { \
x(B); \
} \
} while (0)
#define SCANELF_ELF_SIZED(x) \
do { \
_SCANELF_IF_ELF_SIZE(32, x); \
_SCANELF_IF_ELF_SIZE(64, x); \
} while (0)
/* Find the path to a file by name. Note: we do not currently handle the
* empty path element correctly (should behave by searching $PWD). */
static const char *which(const char *fname, const char *envvar)
{
size_t path_len, fname_len;
const char *env_path;
char *path, *p, *ep;
p = getenv(envvar);
if (p)
return p;
env_path = getenv("PATH");
if (!env_path)
return NULL;
/* Create a copy of the $PATH that we can safely modify.
* Make it a little bigger so we can append "/fname".
* We do this twice -- once for a perm copy, and once for
* room at the end of the last element. */
path_len = strlen(env_path);
fname_len = strlen(fname);
path = xmalloc(path_len + (fname_len * 2) + 2 + 2);
memcpy(path, env_path, path_len + 1);
p = path + path_len + 1 + fname_len + 1;
*p = '/';
memcpy(p + 1, fname, fname_len + 1);
/* Repoint fname to the copy in the env string as it has
* the leading slash which we can include in a single memcpy.
* Increase the fname len to include the '/' and '\0'. */
fname = p;
fname_len += 2;
p = path;
while (p) {
ep = strchr(p, ':');
/* Append the /foo path to the current element. */
if (ep)
memcpy(ep, fname, fname_len);
else
memcpy(path + path_len, fname, fname_len);
if (access(p, R_OK) != -1)
return p;
p = ep;
if (ep) {
/* If not the last element, restore the chunk we clobbered. */
size_t offset = ep - path;
size_t restore = min(path_len - offset, fname_len);
memcpy(ep, env_path + offset, restore);
++p;
}
}
free(path);
return NULL;
}
/*
* Return the index into the program header table for the |p_type| segment.
* Useful only when there is one instance of a particular type.
*/
static ssize_t scanelf_file_find_phdr(elfobj *elf, uint32_t p_type)
{
ssize_t ret = -1;
#define FIND_PT_TYPE(B) \
size_t i; \
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) != p_type) \
continue; \
\
if (ret == -1) \
ret = i; \
else \
warnf("ELF has more than one %s segment !?", get_elfptype(p_type)); \
}
if (elf->phdr)
SCANELF_ELF_SIZED(FIND_PT_TYPE);
return ret;
}
static void *scanelf_file_get_pt_dynamic(elfobj *elf)
{
ssize_t i = scanelf_file_find_phdr(elf, PT_DYNAMIC);
if (i == -1)
return NULL;
#define CHECK_PT_DYNAMIC(B) \
Elf##B##_Phdr *phdr = &PHDR##B(elf->phdr)[i]; \
Elf##B##_Off offset; \
\
if (EGET(phdr->p_filesz) == 0) \
break; \
offset = EGET(phdr->p_offset); \
if (!VALID_RANGE(elf, offset, sizeof(Elf##B##_Dyn))) \
break; \
return phdr;
SCANELF_ELF_SIZED(CHECK_PT_DYNAMIC);
return NULL;
}
#define scanelf_dt_for_each(B, elf, dyn) \
{ \
Elf##B##_Phdr *_phdr = scanelf_file_get_pt_dynamic(elf); \
dyn = (_phdr == NULL) ? elf->data_end : DYN##B(elf->vdata + EGET(_phdr->p_offset)); \
} \
--dyn; \
while ((void *)++dyn < elf->data_end - sizeof(*dyn) && EGET(dyn->d_tag) != DT_NULL)
/* sub-funcs for scanelf_fileat() */
static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **str)
{
/* find the best SHT_DYNSYM and SHT_STRTAB sections */
/* debug sections */
void *symtab = elf_findsecbyname(elf, ".symtab");
void *strtab = elf_findsecbyname(elf, ".strtab");
/* runtime sections */
void *dynsym = elf_findsecbyname(elf, ".dynsym");
void *dynstr = elf_findsecbyname(elf, ".dynstr");
/*
* If the sections are marked NOBITS, then they don't exist, so we just
* skip them. This let's us work sanely with splitdebug ELFs (rather
* than spewing a lot of "corrupt ELF" messages later on). In malformed
* ELFs, the section might be wrongly set to NOBITS, but screw em.
*
* We need to make sure the debug/runtime sym/str sets are used together
* as they are generated in sync. Trying to mix them won't work.
*/
#define GET_SYMTABS(B) \
Elf ## B ## _Shdr *esymtab = symtab; \
Elf ## B ## _Shdr *estrtab = strtab; \
Elf ## B ## _Shdr *edynsym = dynsym; \
Elf ## B ## _Shdr *edynstr = dynstr; \
\
if (!VALID_SHDR(elf, esymtab)) \
symtab = NULL; \
if (!VALID_SHDR(elf, edynsym)) \
dynsym = NULL; \
if (!VALID_SHDR(elf, estrtab)) \
strtab = NULL; \
if (!VALID_SHDR(elf, edynstr)) \
dynstr = NULL; \
\
/* Use the set with more symbols if both exist. */ \
if (symtab && dynsym && strtab && dynstr) { \
if (EGET(esymtab->sh_size) > EGET(edynsym->sh_size)) \
goto debug##B; \
else \
goto runtime##B; \
} else if (symtab && strtab) { \
debug##B: \
*sym = symtab; \
*str = strtab; \
return; \
} else if (dynsym && dynstr) { \
runtime##B: \
*sym = dynsym; \
*str = dynstr; \
return; \
} else { \
*sym = *str = NULL; \
}
SCANELF_ELF_SIZED(GET_SYMTABS);
if (*sym && *str)
return;
/*
* damn, they're really going to make us work for it huh?
* reconstruct the section header info out of the dynamic
* tags so we can see what symbols this guy uses at runtime.
*/
#define GET_SYMTABS_DT(B) \
size_t i; \
static Elf ## B ## _Shdr sym_shdr, str_shdr; \
Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
Elf ## B ## _Phdr *phdr = PHDR ## B (elf->phdr); \
Elf ## B ## _Addr vsym, vstr, vhash, vgnu_hash; \
Elf ## B ## _Dyn *dyn; \
\
/* lookup symbols used at runtime with DT_SYMTAB / DT_STRTAB */ \
vsym = vstr = vhash = vgnu_hash = 0; \
memset(&sym_shdr, 0, sizeof(sym_shdr)); \
memset(&str_shdr, 0, sizeof(str_shdr)); \
\
/* Find the dynamic headers */ \
scanelf_dt_for_each(B, elf, dyn) { \
switch (EGET(dyn->d_tag)) { \
case DT_SYMTAB: vsym = EGET(dyn->d_un.d_val); break; \
case DT_SYMENT: sym_shdr.sh_entsize = dyn->d_un.d_val; break; \
case DT_STRTAB: vstr = EGET(dyn->d_un.d_val); break; \
case DT_STRSZ: str_shdr.sh_size = dyn->d_un.d_val; break; \
case DT_HASH: vhash = EGET(dyn->d_un.d_val); break; \
/*case DT_GNU_HASH: vgnu_hash = EGET(dyn->d_un.d_val); break;*/ \
} \
} \
if (!vsym || !vstr || !(vhash || vgnu_hash)) \
return; \
\
/* calc offset into the ELF by finding the load addr of the syms */ \
for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
Elf ## B ## _Addr vaddr = EGET(phdr[i].p_vaddr); \
Elf ## B ## _Addr filesz = EGET(phdr[i].p_filesz); \
Elf ## B ## _Off offset = EGET(phdr[i].p_offset); \
Elf ## B ## _Off hash_offset = offset + (vhash - vaddr); \
\
if (EGET(phdr[i].p_type) != PT_LOAD) \
continue; \
\
if (!VALID_RANGE(elf, offset, filesz)) \
goto corrupt_hash; \
if (!VALID_RANGE(elf, hash_offset, sizeof(Elf32_Word) * 4)) \
goto corrupt_hash; \
\
if (vhash >= vaddr && vhash < vaddr + filesz) { \
/* Scan the hash table to see how many entries we have */ \
Elf32_Word max_sym_idx = 0; \
Elf32_Word *hashtbl = elf->vdata + hash_offset; \
Elf32_Word b, nbuckets = EGET(hashtbl[0]); \
Elf32_Word nchains = EGET(hashtbl[1]); \
Elf32_Word *buckets = &hashtbl[2]; \
Elf32_Word *chains = &buckets[nbuckets]; \
Elf32_Word sym_idx; \
Elf32_Word chained; \
\
if (!VALID_RANGE(elf, offset, nbuckets * 4)) \
goto corrupt_hash; \
if (!VALID_RANGE(elf, offset, nchains * 4)) \
goto corrupt_hash; \
\
for (b = 0; b < nbuckets; ++b) { \
if (!buckets[b]) \
continue; \
for (sym_idx = buckets[b], chained = 0; \
(sym_idx < nchains && sym_idx && chained <= nchains && \
(void *)&chains[sym_idx] + sizeof(*chains) < elf->data_end); \
sym_idx = chains[sym_idx], ++chained) { \
if (max_sym_idx < sym_idx) \
max_sym_idx = sym_idx; \
} \
if (chained > nchains) \
goto corrupt_hash; \
} \
ESET(sym_shdr.sh_size, sym_shdr.sh_entsize * max_sym_idx); \
} \
\
if (vsym >= vaddr && vsym < vaddr + filesz) { \
Elf##B##_Shdr *shdr = &sym_shdr; \
ESET(sym_shdr.sh_offset, offset + (vsym - vaddr)); \
if (VALID_SHDR(elf, shdr)) \
*sym = shdr; \
} \
\
if (vstr >= vaddr && vstr < vaddr + filesz) { \
Elf##B##_Shdr *shdr = &str_shdr; \
ESET(str_shdr.sh_offset, offset + (vstr - vaddr)); \
if (VALID_SHDR(elf, shdr)) \
*str = shdr; \
} \
}
if (elf->phdr)
SCANELF_ELF_SIZED(GET_SYMTABS_DT);
return;
corrupt_hash:
warn("%s: ELF hash table is corrupt", elf->filename);
}
static const 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));
#define SHOW_PAX(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; \
}
if (elf->phdr)
SCANELF_ELF_SIZED(SHOW_PAX);
/* Note: We do not support setting EI_PAX if not PT_PAX_FLAGS
* was found. This is known to break ELFs on glibc systems,
* and mainline PaX has deprecated use of this for a long time.
* We could support changing PT_GNU_STACK, but that doesn't
* seem like it's worth the effort. #411919
*/
/* fall back to EI_PAX if no PT_PAX was found */
if (!*ret) {
const char *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);
}
strcpy(ret, paxflags);
}
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;
if (!show_phdr) return NULL;
memcpy(ret, "--- --- ---\0", 12);
shown = 0;
multi_stack = multi_relro = multi_load = 0;
#define NOTE_GNU_STACK ".note.GNU-stack"
#define SHOW_PHDR(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 (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); \
uint16_t shstrndx = EGET(ehdr->e_shstrndx); \
Elf ## B ## _Shdr *strtbl = shdr + shstrndx; \
uint16_t shnum = EGET(ehdr->e_shnum); \
if (shstrndx >= shnum || !VALID_SHDR(elf, strtbl)) \
goto corrupt_shdr; \
/* let's flag -w/+x object files since the final ELF will most likely \
* need write access to the stack (who doesn't !?). so the combined \
* output will bring in +w automatically and that's bad. \
*/ \
check_flags = /*SHF_WRITE|*/SHF_EXECINSTR; \
for (i = 0; i < shnum; ++i) { \
if (EGET(shdr[i].sh_type) != SHT_PROGBITS) continue; \
offset = EGET(strtbl->sh_offset) + EGET(shdr[i].sh_name); \
if (!VALID_RANGE(elf, offset, sizeof(NOTE_GNU_STACK))) \
continue; \
if (!strcmp(elf->data + offset, NOTE_GNU_STACK)) { \
if (multi_stack++) warnf("%s: multiple .note.GNU-stack's !?", elf->filename); \
if (file_matches_list(elf->filename, qa_execstack)) \
continue; \
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; \
} \
} \
if (!multi_stack) { \
if (file_matches_list(elf->filename, qa_execstack)) \
return NULL; \
*found_phdr = 1; \
shown = 1; \
memcpy(ret, "!WX", 3); \
} \
}
SCANELF_ELF_SIZED(SHOW_PHDR);
if (be_wewy_wewy_quiet || (be_quiet && !shown))
return NULL;
else
return ret;
corrupt_shdr:
warnf("%s: section table is corrupt", elf->filename);
return NULL;
}
/*
* See if this ELF contains a DT_TEXTREL tag in any of its
* PT_DYNAMIC sections.
*/
static const char *scanelf_file_textrel(elfobj *elf, char *found_textrel)
{
static const char *ret = "TEXTREL";
if (!show_textrel && !show_textrels) return NULL;
if (file_matches_list(elf->filename, qa_textrels)) return NULL;
#define SHOW_TEXTREL(B) \
Elf ## B ## _Dyn *dyn; \
\
scanelf_dt_for_each(B, elf, dyn) { \
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); \
} \
}
if (elf->phdr)
SCANELF_ELF_SIZED(SHOW_TEXTREL);
if (be_quiet || be_wewy_wewy_quiet)
return NULL;
else
return " - ";
}
/*
* Scan the .text section to see if there are any relocations in it.
* Should rewrite this to check PT_LOAD sections that are marked
* Executable rather than the section named '.text'.
*/
static char *scanelf_file_textrels(elfobj *elf, char *found_textrels, char *found_textrel)
{
unsigned long r, rmax;
void *symtab_void, *strtab_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);
#define SHOW_TEXTRELS(B) \
size_t i; \
Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
Elf ## B ## _Phdr *phdr; \
Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
Elf ## B ## _Rel *rel; \
Elf ## B ## _Rela *rela; \
Elf ## B ## _Dyn *dyn, *drel, *drelsz, *drelent, *dpltrel; \
uint32_t pltrel; \
\
/* Walk all the dynamic tags to find relocation info */ \
drel = drelsz = drelent = dpltrel = NULL; \
scanelf_dt_for_each(B, elf, dyn) { \
switch (EGET(dyn->d_tag)) { \
case DT_REL: \
case DT_RELA: \
drel = dyn; \
break; \
case DT_RELSZ: \
case DT_RELASZ: \
drelsz = dyn; \
break; \
case DT_RELENT: \
case DT_RELAENT: \
drelent = dyn; \
break; \
case DT_PLTREL: \
dpltrel = dyn; \
break; \
} \
} \
if (!drel || !drelsz || !drelent || !dpltrel) { \
warnf("ELF is missing relocation information"); \
break; \
} \
switch (EGET(dpltrel->d_un.d_val)) { \
case DT_REL: \
rel = REL##B(elf->vdata + EGET(drel->d_un.d_val)); \
rela = NULL; \
pltrel = DT_REL; \
break; \
case DT_RELA: \
rel = NULL; \
rela = RELA##B(elf->vdata + EGET(drel->d_un.d_val)); \
pltrel = DT_RELA; \
break; \
default: \
warn("Unknown relocation type"); \
rel = NULL; \
rela = NULL; \
break; \
} \
if (!rel && !rela) \
break; \
rmax = EGET(drelsz->d_un.d_val) / EGET(drelent->d_un.d_val); \
\
/* search the program segments for relocations */ \
phdr = PHDR ## B(elf->phdr); \
for (i = 0; i < EGET(ehdr->e_phnum); ++i) { \
Elf ## B ## _Addr vaddr = EGET(phdr[i].p_vaddr); \
uint ## B ## _t memsz = EGET(phdr[i].p_memsz); \
\
/* Only care about loadable segments. */ \
if (EGET(phdr[i].p_type) != PT_LOAD) \
continue; \
/* Only care about executable segments. */ \
if ((EGET(phdr[i].p_flags) & PF_X) != PF_X) \
continue; \
\
/* now see if any of the relocs touch this segment */ \
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 (pltrel == DT_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->vdata + EGET(symtab->sh_offset)); \
if ((void*)sym > 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 (!strtab) \
printf("(missing symbols)"); \
else if (sym && sym->st_name) \
printf("%s", 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->vdata + 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) { \
if (strtab) { \
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("(missing symbols)"); \
} else \
printf("(optimized out)"); \
printf(" [0x%lX]\n", (unsigned long)offset_tmp); \
if (be_verbose && objdump) { \
Elf ## B ## _Addr end_addr = offset_tmp + EGET(func->st_size); \
char *sysbuf; \
size_t syslen; \
const char sysfmt[] = "%s -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(objdump) + strlen(elf->filename) + 3 * sizeof(unsigned long) + 1; \
sysbuf = xmalloc(syslen); \
if (end_addr < r_offset) \
/* not uncommon when things are optimized out */ \
end_addr = r_offset + 0x100; \
snprintf(sysbuf, syslen, sysfmt, \
objdump, \
(unsigned long)offset_tmp, \
(unsigned long)end_addr, \
elf->filename, \
(unsigned long)r_offset); \
fflush(stdout); \
if (system(sysbuf)) {/* don't care */} \
fflush(stdout); \
free(sysbuf); \
} \
} \
}
if (symtab_void && elf->phdr)
SCANELF_ELF_SIZED(SHOW_TEXTRELS);
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 *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;
}
if (fix_elf)
warnf("Note: RPATH has been automatically fixed, but this should be fixed in the package itself");
}
static void scanelf_file_rpath(elfobj *elf, char *found_rpath, char **ret, size_t *ret_len)
{
char *rpath, *runpath, **r;
void *strtab_void;
if (!show_rpath) return;
/*
* TODO: Switch to the string table found via dynamic tags.
* Note: We can't use scanelf_file_get_symtabs as these strings are
* *only* found in dynstr and not in .strtab.
*/
strtab_void = elf_findsecbyname(elf, ".dynstr");
rpath = runpath = NULL;
#define SHOW_RPATH(B) \
Elf ## B ## _Dyn *dyn; \
Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
Elf ## B ## _Off offset; \
Elf ## B ## _Xword word; \
\
/* Just scan dynamic RPATH/RUNPATH headers */ \
scanelf_dt_for_each(B, elf, dyn) { \
word = EGET(dyn->d_tag); \
if (word == DT_RPATH) { \
r = &rpath; \
} else if (word == DT_RUNPATH) { \
r = &runpath; \
} else { \
continue; \
} \
/* Verify the memory is somewhat sane */ \
offset = EGET(strtab->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 = 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 ? (size_t)(end - start) : strlen(start)); \
if (use_ldcache) { \
size_t n; \
const char *ldpath; \
array_for_each(ldpaths, n, ldpath) \
if (!strncmp(ldpath, start, len) && !ldpath[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; \
} \
} \
}
if (elf->phdr && strtab_void)
SCANELF_ELF_SIZED(SHOW_RPATH);
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);
}
static char *lookup_config_lib(const char *fname)
{
static char buf[__PAX_UTILS_PATH_MAX] = "";
const char *ldpath;
size_t n;
array_for_each(ldpaths, n, ldpath) {
snprintf(buf, sizeof(buf), "%s/%s", root_rel_path(ldpath), fname);
if (faccessat(root_fd, buf, F_OK, AT_SYMLINK_NOFOLLOW) == 0)
return buf;
}
return NULL;
}
static const char *scanelf_file_needed_lib(elfobj *elf, char *found_needed, char *found_lib, int op, char **ret, size_t *ret_len)
{
char *needed;
void *strtab_void;
char *p;
/*
* -n -> op==0 -> print all
* -N -> op==1 -> print requested
*/
if ((op == 0 && !show_needed) || (op == 1 && !find_lib))
return NULL;
/*
* TODO: Switch to the string table found via dynamic tags.
* Note: We can't use scanelf_file_get_symtabs as these strings are
* *only* found in dynstr and not in .strtab.
*/
strtab_void = elf_findsecbyname(elf, ".dynstr");
#define SHOW_NEEDED(B) \
Elf ## B ## _Dyn *dyn; \
Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
size_t matched = 0; \
\
/* Walk all the dynamic tags to find NEEDED entries */ \
scanelf_dt_for_each(B, elf, dyn) { \
if (EGET(dyn->d_tag) == DT_NEEDED) { \
Elf ## B ## _Off offset = EGET(strtab->sh_offset) + EGET(dyn->d_un.d_ptr); \
if (offset >= (Elf ## B ## _Off)elf->len) \
continue; \
needed = elf->data + offset; \
if (op == 0) { \
/* -n -> print all entries */ \
if (!be_wewy_wewy_quiet) { \
if (*found_needed) xchrcat(ret, ',', ret_len); \
if (use_ldpath) { \
if ((p = lookup_config_lib(needed)) != NULL) \
needed = p; \
} else if (use_ldcache) { \
if ((p = ldso_cache_lookup_lib(elf, needed)) != NULL) \
needed = p; \
} \
xstrcat(ret, needed, ret_len); \
} \
*found_needed = 1; \
} else { \
/* -N -> print matching entries */ \
size_t n; \
const char *find_lib_name; \
\
array_for_each(find_lib_arr, n, find_lib_name) { \
int invert = 1; \
if (find_lib_name[0] == '!') \
invert = 0, ++find_lib_name; \
if ((!strcmp(find_lib_name, needed)) == invert) \
++matched; \
} \
\
if (matched == array_cnt(find_lib_arr)) { \
*found_lib = 1; \
return (be_wewy_wewy_quiet ? NULL : find_lib); \
} \
} \
} \
}
if (elf->phdr && strtab_void) {
SCANELF_ELF_SIZED(SHOW_NEEDED);
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)
{
uint64_t offset = 0;
if (!show_interp) return NULL;
if (elf->phdr) {
/* Walk all the program headers to find the PT_INTERP */
#define GET_PT_INTERP(B) \
size_t i; \
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_INTERP) { \
offset = EGET(phdr[i].p_offset); \
break; \
} \
}
SCANELF_ELF_SIZED(GET_PT_INTERP);
} else if (elf->shdr) {
/* Use the section headers to find it */
void *section = elf_findsecbyname(elf, ".interp");
#define GET_INTERP(B) \
Elf ## B ## _Shdr *shdr = SHDR ## B (section); \
offset = EGET(shdr->sh_offset);
if (section)
SCANELF_ELF_SIZED(GET_INTERP);
}
/* Validate the pointer even if we don't use it in output */
if (offset && offset <= (uint64_t)elf->len) {
char *interp = elf->data + offset;
/* If it isn't a C pointer, it's garbage */
if (memchr(interp, 0, elf->len - offset)) {
*found_interp = 1;
if (!be_wewy_wewy_quiet)
return interp;
}
}
return NULL;
}
static const char *scanelf_file_bind(elfobj *elf, char *found_bind)
{
struct stat s;
bool dynamic = false;
if (!show_bind) return NULL;
if (!elf->phdr) return NULL;
#define SHOW_BIND(B) \
Elf ## B ## _Dyn *dyn; \
\
scanelf_dt_for_each(B, elf, dyn) { \
dynamic = true; \
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"); \
} \
}
SCANELF_ELF_SIZED(SHOW_BIND);
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 dynamic ? "LAZY" : "STATIC";
}
}
static char *scanelf_file_soname(elfobj *elf, char *found_soname)
{
char *soname;
void *strtab_void;
if (!show_soname) return NULL;
/*
* TODO: Switch to the string table found via dynamic tags.
* Note: We can't use scanelf_file_get_symtabs as these strings are
* *only* found in dynstr and not in .strtab.
*/
strtab_void = elf_findsecbyname(elf, ".dynstr");
#define SHOW_SONAME(B) \
Elf ## B ## _Dyn *dyn; \
Elf ## B ## _Ehdr *ehdr = EHDR ## B (elf->ehdr); \
Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
\
/* only look for soname in shared objects */ \
if (EGET(ehdr->e_type) != ET_DYN) \
return NULL; \
\
scanelf_dt_for_each(B, elf, dyn) { \
if (EGET(dyn->d_tag) == DT_SONAME) { \
Elf ## B ## _Off offset = EGET(strtab->sh_offset) + EGET(dyn->d_un.d_ptr); \
if (offset >= (Elf ## B ## _Off)elf->len) \
continue; \
soname = elf->data + offset; \
*found_soname = 1; \
return (be_wewy_wewy_quiet ? NULL : soname); \
} \
}
if (elf->phdr && strtab_void)
SCANELF_ELF_SIZED(SHOW_SONAME);
return NULL;
}
/*
* We support the symbol form:
* [%[modifiers]%][[+-]<symbol name>][,[.....]]
* If the symbol name is empty, then all symbols are matched.
* If the symbol name is a glob ("*"), then all symbols are dumped (debug).
* Do not rely on this output format at all.
* Otherwise the symbol name is used to search (either regex or string compare).
* If the first char of the symbol name is a plus ("+"), then only match
* defined symbols. If it's a minus ("-"), only match undefined symbols.
* Putting modifiers in between the percent signs allows for more in depth
* filters. There are groups of modifiers. If you don't specify a member
* of a group, then all types in that group are matched. The current
* groups and their types are:
* STT group: STT_NOTYPE:n STT_OBJECT:o STT_FUNC:f STT_FILE:F
* STB group: STB_LOCAL:l STB_GLOBAL:g STB_WEAK:w
* STV group: STV_DEFAULT:p STV_INTERNAL:i STV_HIDDEN:h STV_PROTECTED:P
* SHN group: SHN_UNDEF:u SHN_ABS:a SHN_COMMON:c {defined}:d
* The "defined" value in the SHN group does not correspond to a SHN_xxx define.
* You can search for multiple symbols at once by seperating with a comma (",").
*
* Some examples:
* ELFs with a weak function "foo":
* scanelf -s %wf%foo <ELFs>
* ELFs that define the symbol "main":
* scanelf -s +main <ELFs>
* scanelf -s %d%main <ELFs>
* ELFs that refer to the undefined symbol "brk":
* scanelf -s -brk <ELFs>
* scanelf -s %u%brk <ELFs>
* All global defined objects in an ELF:
* scanelf -s %ogd% <ELF>
*/
static void
scanelf_match_symname(elfobj *elf, char *found_sym, char **ret, size_t *ret_len, const char *symname,
unsigned int stt, unsigned int stb, unsigned int stv, unsigned int shn, unsigned long size)
{
const char *this_sym;
size_t n;
array_for_each(find_sym_arr, n, this_sym) {
bool inc_notype, inc_object, inc_func, inc_file,
inc_local, inc_global, inc_weak,
inc_visdef, inc_intern, inc_hidden, inc_prot,
inc_def, inc_undef, inc_abs, inc_common;
/* symbol selection! */
inc_notype = inc_object = inc_func = inc_file =
inc_local = inc_global = inc_weak =
inc_visdef = inc_intern = inc_hidden = inc_prot =
inc_def = inc_undef = inc_abs = inc_common =
(*this_sym != '%');
/* parse the contents of %...% */
if (!inc_notype) {
while (*(this_sym++)) {
if (*this_sym == '%') {
++this_sym;
break;
}
switch (*this_sym) {
case 'n': inc_notype = true; break;
case 'o': inc_object = true; break;
case 'f': inc_func = true; break;
case 'F': inc_file = true; break;
case 'l': inc_local = true; break;
case 'g': inc_global = true; break;
case 'w': inc_weak = true; break;
case 'p': inc_visdef = true; break;
case 'i': inc_intern = true; break;
case 'h': inc_hidden = true; break;
case 'P': inc_prot = true; break;
case 'd': inc_def = true; break;
case 'u': inc_undef = true; break;
case 'a': inc_abs = true; break;
case 'c': inc_common = true; break;
default: err("invalid symbol selector '%c'", *this_sym);
}
}
/* If no types are matched, not match all */
if (!inc_notype && !inc_object && !inc_func && !inc_file)
inc_notype = inc_object = inc_func = inc_file = true;
if (!inc_local && !inc_global && !inc_weak)
inc_local = inc_global = inc_weak = true;
if (!inc_visdef && !inc_intern && !inc_hidden && !inc_prot)
inc_visdef = inc_intern = inc_hidden = inc_prot = true;
if (!inc_def && !inc_undef && !inc_abs && !inc_common)
inc_def = inc_undef = inc_abs = inc_common = true;
/* backwards compat for defined/undefined short hand */
} else if (*this_sym == '+') {
inc_undef = false;
++this_sym;
} else if (*this_sym == '-') {
inc_def = inc_abs = inc_common = false;
++this_sym;
}
/* filter symbols */
if ((!inc_notype && stt == STT_NOTYPE ) || \
(!inc_object && stt == STT_OBJECT ) || \
(!inc_func && stt == STT_FUNC ) || \
(!inc_file && stt == STT_FILE ) || \
(!inc_local && stb == STB_LOCAL ) || \
(!inc_global && stb == STB_GLOBAL ) || \
(!inc_weak && stb == STB_WEAK ) || \
(!inc_visdef && stv == STV_DEFAULT ) || \
(!inc_intern && stv == STV_INTERNAL ) || \
(!inc_hidden && stv == STV_HIDDEN ) || \
(!inc_prot && stv == STV_PROTECTED) || \
(!inc_def && shn && shn < SHN_LORESERVE) || \
(!inc_undef && shn == SHN_UNDEF ) || \
(!inc_abs && shn == SHN_ABS ) || \
(!inc_common && shn == SHN_COMMON ))
continue;
if (*this_sym == '*') {
/* a "*" symbol gets you debug output */
printf("%s(%s) %5lX %-15s %-15s %-15s %-15s %s\n",
((*found_sym == 0) ? "\n\t" : "\t"),
elf->base_filename,
size,
get_elfstttype(stt),
get_elfstbtype(stb),
get_elfstvtype(stv),
get_elfshntype(shn),
symname);
goto matched;
} else {
if (g_match) {
/* regex match the symbol */
if (regexec(find_sym_regex_arr->eles[n], symname, 0, NULL, 0) == REG_NOMATCH)
continue;
} else if (*this_sym) {
/* give empty symbols a "pass", else do a normal compare */
const size_t len = strlen(this_sym);
if (!(strncmp(this_sym, symname, len) == 0 &&
/* Accept unversioned symbol names */
(symname[len] == '\0' || symname[len] == '@')))
continue;
}
if (be_semi_verbose) {
char buf[1024];
snprintf(buf, sizeof(buf), "%lX %s %s",
size,
get_elfstttype(stt),
this_sym);
*ret = xstrdup(buf);
} else {
if (*ret) xchrcat(ret, ',', ret_len);
xstrcat(ret, symname, ret_len);
}
goto matched;
}
}
return;
matched:
*found_sym = 1;
}
static char *scanelf_file_sym(elfobj *elf, char *found_sym)
{
char *ret;
void *symtab_void, *strtab_void;
if (!find_sym) return NULL;
ret = NULL;
scanelf_file_get_symtabs(elf, &symtab_void, &strtab_void);
#define FIND_SYM(B) \
Elf ## B ## _Shdr *symtab = SHDR ## B (symtab_void); \
Elf ## B ## _Shdr *strtab = SHDR ## B (strtab_void); \
Elf ## B ## _Sym *sym = SYM ## B (elf->vdata + EGET(symtab->sh_offset)); \
Elf ## B ## _Word i, cnt = EGET(symtab->sh_entsize); \
char *symname; \
size_t ret_len = 0; \
if (cnt) \
cnt = EGET(symtab->sh_size) / cnt; \
for (i = 0; i < cnt; ++i) { \
if ((void *)sym >= elf->data_end - sizeof(*sym)) \
goto break_out; \
if (sym->st_name) { \
/* make sure the symbol name is in acceptable memory range */ \
symname = elf->data + EGET(strtab->sh_offset) + EGET(sym->st_name); \
if (EGET(sym->st_name) >= (uint64_t)elf->len || \
EGET(strtab->sh_offset) + EGET(sym->st_name) >= (uint64_t)elf->len || \
!memchr(symname, 0, elf->len - EGET(strtab->sh_offset) + EGET(sym->st_name))) \
goto break_out; \
scanelf_match_symname(elf, found_sym, \
&ret, &ret_len, symname, \
ELF##B##_ST_TYPE(EGET(sym->st_info)), \
ELF##B##_ST_BIND(EGET(sym->st_info)), \
ELF##B##_ST_VISIBILITY(EGET(sym->st_other)), \
EGET(sym->st_shndx), \
/* st_size can be 64bit, but no one is really that big, so screw em */ \
EGET(sym->st_size)); \
} \
++sym; \
}
if (symtab_void && strtab_void)
SCANELF_ELF_SIZED(FIND_SYM);
if (be_wewy_wewy_quiet) {
free(ret);
return NULL;
}
if (*find_sym != '*' && *found_sym)
return ret;
else
free(ret);
if (be_quiet)
return NULL;
else
return xstrdup(" - ");
break_out:
warnf("%s: corrupt ELF symbols", elf->filename);
free(ret);
return NULL;
}
static const char *scanelf_file_sections(elfobj *elf, char *found_section)
{
if (!find_section)
return NULL;
#define FIND_SECTION(B) \
size_t matched, n; \
int invert; \
const char *section_name; \
Elf ## B ## _Shdr *section; \
\
matched = 0; \
array_for_each(find_section_arr, n, section_name) { \
invert = (*section_name == '!' ? 1 : 0); \
section = SHDR ## B (elf_findsecbyname(elf, section_name + invert)); \
if ((section == NULL && invert) || (section != NULL && !invert)) \
++matched; \
} \
\
if (matched == array_cnt(find_section_arr)) \
*found_section = 1;
SCANELF_ELF_SIZED(FIND_SECTION);
if (be_wewy_wewy_quiet)
return NULL;
if (*found_section)
return find_section;
if (be_quiet)
return NULL;
else
return " - ";
}
/* scan an elf file and show all the fun stuff */
#define prints(str) ({ ssize_t ret = write(fileno(stdout), str, strlen(str)); ret; })
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 = 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 'l':
case 'n': prints("NEEDED "); break;
case 'i': prints("INTERP "); break;
case 'b': prints("BIND "); break;
case 'Z': prints("SIZE "); 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;
case 'I': prints("OSABI "); break;
case 'Y': prints("EABI "); break;
case 'O': prints("PERM "); break;
case 'D': prints("ENDIAN "); 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) {
char *allocated;
const char *out;
const char *tmp;
static char ubuf[sizeof(unsigned long)*2];
if (!IS_MODIFIER(out_format[i])) {
xchrcat(&out_buffer, out_format[i], &out_len);
continue;
}
out = allocated = 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 'D': out = get_endian(elf); break;
case 'O': out = strfileperms(elf->filename); 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 = allocated = scanelf_file_sym(elf, &found_sym); break;
case 'k': out = scanelf_file_sections(elf, &found_section); break;
case 'a': out = get_elfemtype(elf); break;
case 'I': out = get_elfosabi(elf); break;
case 'Y': out = get_elf_eabi(elf); break;
case 'Z': snprintf(ubuf, sizeof(ubuf), "%"PRIu64, (uint64_t)elf->len); out = ubuf; break;;
default: warnf("'%c' has no scan code?", out_format[i]);
}
if (out) {
xstrcat(&out_buffer, out, &out_len);
free(allocated);
}
}
#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;
size_t n;
const char *match_etype;
elfobj *elf;
/* Verify this is a real ELF */
if ((elf = _readelf_fd(filename, fd, len, !fix_elf)) == NULL) {
if (be_verbose > 2) printf("%s: not an ELF\n", filename);
return 2;
}
/* Possibly filter based on ELF bitness */
switch (match_bits) {
case 32:
if (elf->elf_class != ELFCLASS32)
goto done;
break;
case 64:
if (elf->elf_class != ELFCLASS64)
goto done;
break;
}
/* Possibly filter based on the ELF's e_type field */
array_for_each(match_etypes, n, match_etype)
if (etype_lookup(match_etype) == get_etype(elf))
goto scanit;
if (array_cnt(match_etypes))
goto done;
scanit:
ret = scanelf_elfobj(elf);
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, be_verbose);
if (ar == NULL)
return 1;
ar_buffer = mmap(0, len, PROT_READ | (fix_elf ? PROT_WRITE : 0), (fix_elf ? MAP_SHARED : MAP_PRIVATE), fd, 0);
while ((m = ar_next(ar)) != NULL) {
off_t cur_pos = lseek(fd, 0, SEEK_CUR);
if (cur_pos == -1)
errp("lseek() failed");
elf = readelf_buffer(m->name, ar_buffer + cur_pos, 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_fileat(int dir_fd, 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;
fstatat(dir_fd, filename, &symlink_st, 0);
st = &symlink_st;
}
if (!S_ISREG(st->st_mode)) {
if (be_verbose > 2) printf("%s: skipping non-file\n", filename);
return 1;
}
if (match_perms) {
if ((st->st_mode | match_perms) != st->st_mode)
return 1;
}
fd = openat(dir_fd, filename, (fix_elf ? O_RDWR : O_RDONLY) | O_CLOEXEC);
if (fd == -1) {
if (fix_elf && errno == ETXTBSY)
warnp("%s: could not fix", filename);
else if (be_verbose > 2)
printf("%s: skipping file: %s\n", filename, strerror(errno));
return 1;
}
if (scanelf_elf(filename, fd, st->st_size) == 2) {
/* if it isn't an ELF, maybe it's an .a archive */
if (scan_archives)
scanelf_archive(filename, fd, st->st_size);
/*
* unreadelf() implicitly closes its fd, so only close it
* when we are returning it in the non-ELF case
*/
close(fd);
}
return 0;
}
/* scan a directory for ET_EXEC files and print when we find one */
static int scanelf_dirat(int dir_fd, const char *path)
{
register DIR *dir;
register struct dirent *dentry;
struct stat st_top, st;
char buf[__PAX_UTILS_PATH_MAX], *subpath;
size_t pathlen = 0, len = 0;
int ret = 0;
int subdir_fd;
/* make sure path exists */
if (fstatat(dir_fd, path, &st_top, AT_SYMLINK_NOFOLLOW) == -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_fileat(dir_fd, path, &st_top);
/* now scan the dir looking for fun stuff */
subdir_fd = openat(dir_fd, path, O_RDONLY|O_CLOEXEC);
if (subdir_fd == -1)
dir = NULL;
else
dir = fdopendir(subdir_fd);
if (dir == NULL) {
if (subdir_fd != -1)
close(subdir_fd);
else if (be_verbose > 2)
printf("%s: skipping dir: %s\n", path, strerror(errno));
return 1;
}
if (be_verbose > 1) printf("%s: scanning dir\n", path);
subpath = stpcpy(buf, path);
if (subpath[-1] != '/')
*subpath++ = '/';
pathlen = subpath - buf;
while ((dentry = readdir(dir))) {
if (!strcmp(dentry->d_name, ".") || !strcmp(dentry->d_name, ".."))
continue;
if (fstatat(subdir_fd, dentry->d_name, &st, AT_SYMLINK_NOFOLLOW) == -1)
continue;
len = strlen(dentry->d_name);
if (len + pathlen + 1 >= sizeof(buf)) {
warnf("Skipping '%s%s': len > sizeof(buf); %zu > %zu",
path, dentry->d_name, len + pathlen + 1, sizeof(buf));
continue;
}
memcpy(subpath, dentry->d_name, len);
subpath[len] = '\0';
if (S_ISREG(st.st_mode))
ret = scanelf_fileat(dir_fd, buf, &st);
else if (dir_recurse && S_ISDIR(st.st_mode)) {
if (dir_crossmount || (st_top.st_dev == st.st_dev))
ret = scanelf_dirat(dir_fd, buf);
}
}
closedir(dir);
return ret;
}
static int scanelf_dir(const char *path)
{
return scanelf_dirat(root_fd, root_rel_path(path));
}
static int scanelf_from_file(const char *filename)
{
FILE *fp;
char *p, *path;
size_t len;
int ret;
if (strcmp(filename, "-") == 0)
fp = stdin;
else if ((fp = fopen(filename, "r")) == NULL)
return 1;
path = NULL;
len = 0;
ret = 0;
while (getline(&path, &len, fp) != -1) {
if ((p = strchr(path, '\n')) != NULL)
*p = 0;
search_path = path;
ret = scanelf_dir(path);
}
free(path);
if (fp != stdin)
fclose(fp);
return ret;
}
static void load_ld_cache_config(const char *fname)
{
bool scan_l, scan_ul, scan_ull;
size_t n;
const char *ldpath;
ldso_config_load(fname);
scan_l = scan_ul = scan_ull = false;
array_for_each(ldpaths, n, ldpath) {
if (!scan_l && !strcmp(ldpath, "/lib")) scan_l = true;
if (!scan_ul && !strcmp(ldpath, "/usr/lib")) scan_ul = true;
if (!scan_ull && !strcmp(ldpath, "/usr/local/lib")) scan_ull = true;
}
if (!scan_l) xarraypush_str(ldpaths, "/lib");
if (!scan_ul) xarraypush_str(ldpaths, "/usr/lib");
if (!scan_ull) xarraypush_str(ldpaths, "/usr/local/lib");
}
/* scan /etc/ld.so.conf for paths */
static void scanelf_ldpath(void)
{
size_t n;
const char *ldpath;
array_for_each(ldpaths, n, ldpath)
scanelf_dir(ldpath);
}
/* scan env PATH for paths */
static void scanelf_envpath(void)
{
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 */ /* Free Flags: c d j u w G H J K P Q U W */
#define PARSE_FLAGS "plRmyAXz:xetrnLibSs:k:gN:TaqvF:f:o:E:M:DIYO:ZCBhV"
#define a_argument required_argument
static struct option const long_opts[] = {
{"path", no_argument, NULL, 'p'},
{"ldpath", no_argument, NULL, 'l'},
{"use-ldpath",no_argument, NULL, 129},
{"root", a_argument, NULL, 128},
{"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'},
{"endian", no_argument, NULL, 'D'},
{"osabi", no_argument, NULL, 'I'},
{"eabi", no_argument, NULL, 'Y'},
{"perms", a_argument, NULL, 'O'},
{"size", no_argument, NULL, 'Z'},
{"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'},
{"nocolor", no_argument, NULL, 'C'},
{"nobanner", no_argument, NULL, 'B'},
{"help", no_argument, NULL, 'h'},
{"version", no_argument, NULL, 'V'},
{NULL, no_argument, NULL, 0x0}
};
static const char * const opts_help[] = {
"Scan all directories in PATH environment",
"Scan all directories in /etc/ld.so.conf",
"Use ld.so.conf to show full path (use with -r/-n)",
"Root directory (use with -l or -p)",
"Scan directories recursively",
"Don't recursively cross mount points",
"Don't scan symlinks",
"Scan archives (.a files)",
"Utilize ld.so.cache to show full path (use with -r/-n)",
"Try and 'fix' bad things (use with -r/-e)",
"Sets EI_PAX/PT_PAX_FLAGS to <arg> (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 regex rather than string compare (with -s); specify twice for case insensitive",
"Locate cause of TEXTREL",
"Print only ELF files matching etype ET_DYN,ET_EXEC ...",
"Print only ELF files matching numeric bits",
"Print Endianness",
"Print OSABI",
"Print EABI (EM_ARM Only)",
"Print only ELF files matching octal permissions",
"Print ELF file size",
"Print all useful/simple info\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 emit color in output",
"Don't display the header",
"Print this help and exit",
"Print version and exit",
NULL
};
/* display usage and exit */
static void usage(int status)
{
const char a_arg[] = "<arg>";
size_t a_arg_len = strlen(a_arg) + 2;
size_t i;
int optlen;
printf("* Scan ELF binaries for stuff\n\n"
"Usage: %s [options] <dir1/file1> [dir2 dirN file2 fileN ...]\n\n", argv0);
printf("Options: -[%s]\n", PARSE_FLAGS);
/* prescan the --long opt length to auto-align */
optlen = 0;
for (i = 0; long_opts[i].name; ++i) {
int l = strlen(long_opts[i].name);
if (long_opts[i].has_arg == a_argument)
l += a_arg_len;
optlen = max(l, optlen);
}
for (i = 0; long_opts[i].name; ++i) {
/* first output the short flag if it has one */
if (long_opts[i].val > '~')
printf(" ");
else
printf(" -%c, ", long_opts[i].val);
/* then the long flag */
if (long_opts[i].has_arg == no_argument)
printf("--%-*s", optlen, long_opts[i].name);
else
printf("--%s %s %*s", long_opts[i].name, a_arg,
(int)(optlen - strlen(long_opts[i].name) - a_arg_len), "");
/* finally the help text */
printf("* %s\n", 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 void parse_delimited(array_t *arr, char *arg, const char *delim)
{
char *ele = strtok(arg, delim);
if (!ele) /* edge case: -s '' */
xarraypush_str(arr, "");
while (ele) {
xarraypush_str(arr, ele);
ele = strtok(NULL, delim);
}
}
static int parseargs(int argc, char *argv[])
{
int i;
const char *from_file = NULL;
int ret = 0;
char load_cache_config = 0;
opterr = 0;
while ((i=getopt_long(argc, argv, PARSE_FLAGS, long_opts, NULL)) != -1) {
switch (i) {
case 'V':
printf("pax-utils-%s: %s\n"
"%s written for Gentoo by <solar and vapier @ gentoo.org>\n",
VERSION, VCSID, 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':
/* historically, this was comma delimited */
parse_delimited(match_etypes, optarg, ",");
break;
case 'M':
match_bits = atoi(optarg);
if (match_bits == 0) {
if (strcmp(optarg, "ELFCLASS32") == 0)
match_bits = 32;
if (strcmp(optarg, "ELFCLASS64") == 0)
match_bits = 64;
}
break;
case 'O':
if (sscanf(optarg, "%o", &match_perms) == -1)
match_bits = 0;
break;
case 'o': {
if (freopen(optarg, "w", stdout) == NULL)
errp("Could not freopen(%s)", optarg);
break;
}
case 'k':
xarraypush_str(find_section_arr, optarg);
break;
case 's':
/* historically, this was comma delimited */
parse_delimited(find_sym_arr, optarg, ",");
break;
case 'N':
xarraypush_str(find_lib_arr, optarg);
break;
case 'F': {
if (PAX_UTILS_CLEANUP) {
free(out_format);
out_format = xstrdup(optarg);
} else
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 'Z': show_size = 1; break;
case 'g': ++g_match; break;
case 'L': load_cache_config = use_ldcache = 1; break;
case 'y': scan_symlink = 0; break;
case 'A': scan_archives = 1; break;
case 'C': color_init(true); break;
case 'B': show_banner = 0; break;
case 'l': load_cache_config = 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 = min(be_quiet, 20) + 1; break;
case 'v': be_verbose = min(be_verbose, 20) + 1; break;
case 'a': show_perms = show_pax = show_phdr = show_textrel = show_rpath = show_bind = show_endian = 1; break;
case 'D': show_endian = 1; break;
case 'I': show_osabi = 1; break;
case 'Y': show_eabi = 1; break;
case 128:
if (root_fd != AT_FDCWD)
close(root_fd);
root_fd = open(optarg, O_RDONLY|O_CLOEXEC);
if (root_fd == -1)
err("Could not open root: %s", optarg);
break;
case 129: load_cache_config = use_ldpath = 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)
objdump = which("objdump", "OBJDUMP");
/* precompile all the regexes */
if (g_match) {
regex_t preg;
const char *this_sym;
size_t n;
int flags = REG_EXTENDED | REG_NOSUB | (g_match > 1 ? REG_ICASE : 0);
array_for_each(find_sym_arr, n, this_sym) {
/* see scanelf_match_symname for logic info */
switch (this_sym[0]) {
case '%':
while (*(this_sym++))
if (*this_sym == '%') {
++this_sym;
break;
}
break;
case '+':
case '-':
++this_sym;
break;
}
if (*this_sym == '*')
++this_sym;
ret = regcomp(&preg, this_sym, flags);
if (ret) {
char err[256];
regerror(ret, &preg, err, sizeof(err));
err("regcomp of %s failed: %s", this_sym, err);
}
xarraypush(find_sym_regex_arr, &preg, sizeof(preg));
}
}
/* flatten arrays for display */
find_sym = array_flatten_str(find_sym_arr);
find_lib = array_flatten_str(find_lib_arr);
find_section = array_flatten_str(find_section_arr);
/* 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 = show_perms = show_endian = show_size = \
show_osabi = show_eabi = 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 'Z': show_size = 1; break;
case 'D': show_endian = 1; break;
case 'I': show_osabi = 1; break;
case 'Y': show_eabi = 1; break;
case 'O': show_perms = 1; 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 = xmalloc(sizeof(char) * fmt_len);
*out_format = '\0';
if (!be_quiet) xstrcat(&out_format, "%o ", &fmt_len);
if (show_pax) xstrcat(&out_format, "%x ", &fmt_len);
if (show_perms) xstrcat(&out_format, "%O ", &fmt_len);
if (show_size) xstrcat(&out_format, "%Z ", &fmt_len);
if (show_endian) xstrcat(&out_format, "%D ", &fmt_len);
if (show_osabi) xstrcat(&out_format, "%I ", &fmt_len);
if (show_eabi) xstrcat(&out_format, "%Y ", &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 lock down the pidns since we know whether we'll be forking. */
if (!show_textrels || !be_verbose)
security_init_pid();
/* now lets actually do the scanning */
if (load_cache_config)
load_ld_cache_config(__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);
}
if (PAX_UTILS_CLEANUP) {
/* clean up */
xarrayfree(find_sym_arr);
xarrayfree(find_lib_arr);
xarrayfree(find_section_arr);
free(find_sym);
free(find_lib);
free(find_section);
{
size_t n;
regex_t *preg;
array_for_each(find_sym_regex_arr, n, preg)
regfree(preg);
xarrayfree(find_sym_regex_arr);
}
paxldso_cleanup();
}
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(void)
{
color_init(false);
qa_textrels = get_split_env("QA_TEXTRELS");
qa_execstack = get_split_env("QA_EXECSTACK");
qa_wx_load = get_split_env("QA_WX_LOAD");
}
static void cleanup(void)
{
if (!PAX_UTILS_CLEANUP)
return;
free(out_format);
free(qa_textrels);
free(qa_execstack);
free(qa_wx_load);
if (root_fd != AT_FDCWD)
close(root_fd);
}
int main(int argc, char *argv[])
{
int ret;
security_init(true);
if (argc < 2)
usage(EXIT_FAILURE);
parseenv();
ret = parseargs(argc, argv);
fclose(stdout);
cleanup();
return ret;
}
/* 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;
}
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