bool sb_mkdirat_pre_check(const char *func, const char *pathname, int dirfd)
{
char canonic[SB_PATH_MAX];
save_errno();
/* XXX: need to check pathname with dirfd */
if (-1 == canonicalize(pathname, canonic))
/* see comments in check_syscall() */
if (ENAMETOOLONG != errno) {
if (is_env_on(ENV_SANDBOX_DEBUG))
SB_EINFO("EARLY FAIL", " %s(%s) @ canonicalize: %s\n",
func, pathname, strerror(errno));
return false;
}
/* XXX: Hack to prevent errors if the directory exist, and are
* not writable - we rather return EEXIST than fail. This can
* occur if doing something like `mkdir -p /`. We certainly do
* not want to pass this attempt up to the higher levels as those
* will trigger a sandbox violation.
*/
struct stat st;
if (0 == lstat(canonic, &st)) {
if (is_env_on(ENV_SANDBOX_DEBUG))
SB_EINFO("EARLY FAIL", " %s(%s[%s]) @ lstat: %s\n",
func, pathname, canonic, strerror(errno));
errno = EEXIST;
return false;
}
restore_errno();
return true;
}
static inline bool PRE_CHECK_FUNC(WRAPPER_NAME)(_WRAPPER_ARGS_PROTO)
{
if (!(flags & O_CREAT)) {
/* If we're not trying to create, fail normally if
* file does not stat
*/
#if USE_AT
if (dirfd == AT_FDCWD || pathname[0] == '/')
#endif
#undef USE_AT
{
struct stat st;
save_errno();
if (-1 == stat(pathname, &st)) {
if (is_env_on(ENV_SANDBOX_DEBUG))
SB_EINFO("EARLY FAIL", " %s(%s): %s\n",
STRING_NAME, pathname, strerror(errno));
return false;
}
restore_errno();
}
}
return true;
}
static inline bool sb_unlinkat_pre_check(WRAPPER_ARGS_PROTO)
{
char canonic[SB_PATH_MAX];
save_errno();
if (-1 == canonicalize(pathname, canonic))
/* see comments in check_syscall() */
if (ENAMETOOLONG != errno)
goto error;
/* XXX: Hack to make sure sandboxed process cannot remove
* a device node, bug #79836. */
if (0 == strcmp(canonic, "/dev/null") ||
0 == strcmp(canonic, "/dev/zero"))
{
errno = EACCES;
goto error;
}
restore_errno();
return true;
error:
if (is_env_on(ENV_SANDBOX_DEBUG))
SB_EINFO("EARLY FAIL", " %s(%s): %s\n",
STRING_NAME, pathname, strerror(errno));
return false;
}
bool sb_unlinkat_pre_check(const char *func, const char *pathname, int dirfd)
{
char canonic[SB_PATH_MAX];
save_errno();
/* XXX: need to check pathname with dirfd */
if (-1 == canonicalize(pathname, canonic))
/* see comments in check_syscall() */
if (ENAMETOOLONG != errno)
goto error;
/* XXX: Hack to make sure sandboxed process cannot remove
* a device node, bug #79836. */
if (0 == strcmp(canonic, "/dev/null") ||
0 == strcmp(canonic, "/dev/zero"))
{
errno = EACCES;
goto error;
}
restore_errno();
return true;
error:
if (is_env_on(ENV_SANDBOX_DEBUG))
SB_EINFO("EARLY FAIL", " %s(%s): %s\n",
func, pathname, strerror(errno));
return false;
}
bool sb_fopen_pre_check(const char *func, const char *pathname, const char *mode)
{
if ((NULL != mode) && (mode[0] == 'r')) {
save_errno();
/* If we're trying to read, fail normally if file does not stat */
struct stat st;
if (-1 == stat(pathname, &st)) {
if (is_env_on(ENV_SANDBOX_DEBUG))
SB_EINFO("EARLY FAIL", " %s(%s): %s\n",
func, pathname, strerror(errno));
return false;
}
restore_errno();
}
return true;
}