add restricted filesystem access to sel_ldr

src/trusted/service_runtime/nacl_syscall_common.h

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * NaCl service run-time, non-platform specific system call helper routines.
  */
 
@@ skipping 27 matching lines @@
 int32_t NaClSysExit(struct NaClAppThread  *natp,
                     int                   status);
 
 int32_t NaClSysThreadExit(struct NaClAppThread  *natp,
                           uint32_t              stack_flag_addr);
 
 extern int NaClAclBypassChecks;
 
 void NaClInsecurelyBypassAllAclChecks(void);
 
+/*
+ * NaClRootDir will not be NULL when a root dir has been provided and NULL
+ * otherwise. NaClRootDir also never ends with a trailing slash.
+ * The upshot of the last two properties is that when NaClRootDir is set to
+ * "/" the value will be "" with length 0.
+ */
+extern char *NaClRootDir;
+extern size_t NaClRootDirLen;
+
+/* bool */
+int NaClMountRootDir(char *root);
+
+/* bool */
+int NaClFileAccessEnabled(void);
+
+/* bool */
+int NaClSanitizePathLexically(char *path);
+
 /* bool */
 int NaClSysCommonAddrRangeContainsExecutablePages(struct NaClApp *nap,
                                                   uintptr_t usraddr,
                                                   size_t length);
 
 /* bool */
 int NaClSysCommonAddrRangeInAllowedDynamicCodeSpace(struct NaClApp *nap,
                                                     uintptr_t usraddr,
                                                     size_t length);
 
@@ skipping 82 matching lines @@
                        int32_t              name,
                        uint32_t             result_addr);
 
 int32_t NaClSysTestInfoLeak(struct NaClAppThread *natp);
 
 int32_t NaClSysTestCrash(struct NaClAppThread *natp, int crash_type);
 
 EXTERN_C_END
 
 #endif  /* NATIVE_CLIENT_SERVICE_RUNTIME_NACL_SYSCALL_COMMON_H__ */