Only sign modules if --unprivileged is specified.

Don't generate an error message for unsigned modules.
Make sure module signature exists before attempting to copy to the cache.
Allow timer p[robes for unprivileged users.

10 files changed, 132 insertions, 99 deletions

diff --git a/buildrun.cxx b/buildrun.cxx
index 54aa5d4f..effc6cd8 100644
--- a/buildrun.cxx
+++ b/buildrun.cxx
@@ -223,11 +223,12 @@ compile_pass (systemtap_session& s)
   rc = run_make_cmd(s, make_cmd);
 
 #if HAVE_NSS
-  // If a certificate database was specified, then try to sign the module.
+  // If a certificate database was specified, and we're in unprivileged
+  // mode, then try to sign the module.
   // Failure to do so is not a fatal error. If the signature is actually needed,
   // staprun will complain at that time.
   assert (! s.cert_db_path.empty());
-  if (!rc)
+  if (s.unprivileged && ! rc)
     sign_module (s);
 #endif
 
diff --git a/cache.cxx b/cache.cxx
index bfe2b527..200e51e9 100644
--- a/cache.cxx
+++ b/cache.cxx
@@ -79,16 +79,19 @@ add_to_cache(systemtap_session& s)
   string module_signature_src_path = module_src_path;
   module_signature_src_path += ".sgn";
 
-  if (s.verbose > 1)
-    clog << "Copying " << module_signature_src_path << " to " << module_signature_dest_path << endl;
-  if (copy_file(module_signature_src_path.c_str(), module_signature_dest_path.c_str()) != 0)
+  if (file_exists (module_signature_src_path))
     {
-      cerr << "Copy failed (\"" << module_signature_src_path << "\" to \""
-	   << module_signature_dest_path << "\"): " << strerror(errno) << endl;
-      // NB: this is not so severe as to prevent reuse of the .ko
-      // already copied.
-      //
-      // s.use_cache = false;
+      if (s.verbose > 1)
+	clog << "Copying " << module_signature_src_path << " to " << module_signature_dest_path << endl;
+      if (copy_file(module_signature_src_path.c_str(), module_signature_dest_path.c_str()) != 0)
+	{
+	  cerr << "Copy failed (\"" << module_signature_src_path << "\" to \""
+	       << module_signature_dest_path << "\"): " << strerror(errno) << endl;
+	  // NB: this is not so severe as to prevent reuse of the .ko
+	  // already copied.
+	  //
+	  // s.use_cache = false;
+	}
     }
 #endif /* HAVE_NSS */
 
@@ -364,18 +367,6 @@ clean_cache(systemtap_session& s)
     }
 }
 
-// Get the size of a file in bytes
-static size_t
-get_file_size(const string &path)
-{
-  struct stat file_info;
-
-  if (stat(path.c_str(), &file_info) == 0)
-    return file_info.st_size;
-  else
-    return 0;
-}
-
 //Assign a weight for a particular file. A lower weight
 // will be removed before a higher weight.
 //TODO: for now use system mtime... later base a
diff --git a/runtime/staprun/modverify.c b/runtime/staprun/modverify.c
index b50a69f4..f4b15ac3 100644
--- a/runtime/staprun/modverify.c
+++ b/runtime/staprun/modverify.c
@@ -203,11 +203,7 @@ verify_it (const char *inputName, const char *signatureName, SECKEYPublicKey *pu
   /* Get the size of the signature file.  */
   prStatus = PR_GetFileInfo (signatureName, &info);
   if (prStatus != PR_SUCCESS || info.type != PR_FILE_FILE || info.size < 0)
-    {
-      fprintf (stderr, "Unable to obtain information on the signature file %s.\n", signatureName);
-      nssError ();
-      return MODULE_UNTRUSTED; /* Not signed */
-    }
+    return MODULE_UNTRUSTED; /* Not signed */
 
   /* Open the signature file.  */
   local_file_fd = PR_Open (signatureName, PR_RDONLY, 0);
diff --git a/runtime/staprun/staprun_funcs.c b/runtime/staprun/staprun_funcs.c
index 1ebd124e..669dc996 100644
--- a/runtime/staprun/staprun_funcs.c
+++ b/runtime/staprun/staprun_funcs.c
@@ -500,7 +500,7 @@ int check_permissions(void)
 		check_groups_rc = -1;
 	}
 #if HAVE_NSS
-	err("Alternatively, your module must be signed by a trusted signer.\n"
+	err("Alternatively, your module must be compiled using the --unprivileged option and signed by a trusted signer.\n"
 	    "For more information, please consult the \"SAFETY AND SECURITY\" section of the \"stap(1)\" manpage\n");
 #endif
 
diff --git a/tapset-been.cxx b/tapset-been.cxx
index 3f693837..99b59574 100644
--- a/tapset-been.cxx
+++ b/tapset-been.cxx
@@ -215,14 +215,30 @@ register_tapset_been(systemtap_session& s)
 {
   match_node* root = s.pattern_root;
 
-  root->bind(TOK_BEGIN)->allow_unprivileged()->bind(new be_builder(BEGIN));
-  root->bind_num(TOK_BEGIN)->allow_unprivileged()->bind(new be_builder(BEGIN));
-  root->bind(TOK_END)->allow_unprivileged()->bind(new be_builder(END));
-  root->bind_num(TOK_END)->allow_unprivileged()->bind(new be_builder(END));
-  root->bind(TOK_ERROR)->allow_unprivileged()->bind(new be_builder(ERROR));
-  root->bind_num(TOK_ERROR)->allow_unprivileged()->bind(new be_builder(ERROR));
-
-  root->bind(TOK_NEVER)->allow_unprivileged()->bind(new never_builder());
+  root->bind(TOK_BEGIN)
+    ->allow_unprivileged()
+    ->bind(new be_builder(BEGIN));
+  root->bind_num(TOK_BEGIN)
+    ->allow_unprivileged()
+    ->bind(new be_builder(BEGIN));
+
+  root->bind(TOK_END)
+    ->allow_unprivileged()
+    ->bind(new be_builder(END));
+  root->bind_num(TOK_END)
+    ->allow_unprivileged()
+    ->bind(new be_builder(END));
+
+  root->bind(TOK_ERROR)
+    ->allow_unprivileged()
+    ->bind(new be_builder(ERROR));
+  root->bind_num(TOK_ERROR)
+    ->allow_unprivileged()
+    ->bind(new be_builder(ERROR));
+
+  root->bind(TOK_NEVER)
+    ->allow_unprivileged()
+    ->bind(new never_builder());
 }
 
 /* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */
diff --git a/tapset-timers.cxx b/tapset-timers.cxx
index 1dc0acac..565a54e8 100644
--- a/tapset-timers.cxx
+++ b/tapset-timers.cxx
@@ -593,32 +593,71 @@ register_tapset_timers(systemtap_session& s)
 
   root = root->bind(TOK_TIMER);
 
-  root->bind_num("s")->bind(builder);
-  root->bind_num("s")->bind_num("randomize")->bind(builder);
-  root->bind_num("sec")->bind(builder);
-  root->bind_num("sec")->bind_num("randomize")->bind(builder);
-
-  root->bind_num("ms")->bind(builder);
-  root->bind_num("ms")->bind_num("randomize")->bind(builder);
-  root->bind_num("msec")->bind(builder);
-  root->bind_num("msec")->bind_num("randomize")->bind(builder);
-
-  root->bind_num("us")->bind(builder);
-  root->bind_num("us")->bind_num("randomize")->bind(builder);
-  root->bind_num("usec")->bind(builder);
-  root->bind_num("usec")->bind_num("randomize")->bind(builder);
-
-  root->bind_num("ns")->bind(builder);
-  root->bind_num("ns")->bind_num("randomize")->bind(builder);
-  root->bind_num("nsec")->bind(builder);
-  root->bind_num("nsec")->bind_num("randomize")->bind(builder);
-
-  root->bind_num("jiffies")->bind(builder);
-  root->bind_num("jiffies")->bind_num("randomize")->bind(builder);
-
-  root->bind_num("hz")->bind(builder);
-
-  root->bind("profile")->bind(builder);
+  root->bind_num("s")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("s")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("sec")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("sec")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+
+  root->bind_num("ms")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("ms")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("msec")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("msec")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+
+  root->bind_num("us")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("us")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("usec")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("usec")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+
+  root->bind_num("ns")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("ns")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("nsec")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("nsec")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+
+  root->bind_num("jiffies")
+    ->allow_unprivileged()
+    ->bind(builder);
+  root->bind_num("jiffies")->bind_num("randomize")
+    ->allow_unprivileged()
+    ->bind(builder);
+
+  root->bind_num("hz")
+    ->allow_unprivileged()
+    ->bind(builder);
+
+  root->bind("profile")
+    ->bind(builder);
 }
 
 
diff --git a/translate.cxx b/translate.cxx
index 0ef790db..060013bb 100644
--- a/translate.cxx
+++ b/translate.cxx
@@ -66,7 +66,6 @@ struct c_unparser: public unparser, public visitor
   void emit_global_init (vardecl* v);
   void emit_global_param (vardecl* v);
   void emit_functionsig (functiondecl* v);
-  void emit_unprivileged_user_check ();
   void emit_module_init ();
   void emit_module_exit ();
   void emit_function (functiondecl* v);
@@ -1089,30 +1088,6 @@ c_unparser::emit_functionsig (functiondecl* v)
 
 
 void
-c_unparser::emit_unprivileged_user_check ()
-{
-  // If the --unprivileged option was specified then the module
-  // will be safe for unprivileged users, if it is successfully generated,
-  // so no check need be emitted.
-  if (session->unprivileged)
-    return;
-
-  // Otherwise, generate code to check whether the user is unprivileged.
-  // If so, then generate an error and indicate that the check has failed.
-  o->newline();
-  o->newline() << "static int systemtap_unprivileged_user_check (void) {";
-  o->newline(1) << "if (! _stp_unprivileged_user)";
-  o->newline(1) << "return 0;";
-
-  o->newline(-1) << "_stp_error (\"You are attempting to run stap as an ordinary user.\");";
-  o->newline() << "_stp_error (\"Your module must be compiled using the --unprivileged option.\");";
-  o->newline() << "return 1;";
-
-  o->newline(-1) << "}\n";
-}
-
-
-void
 c_unparser::emit_module_init ()
 {
   vector<derived_probe_group*> g = all_session_groups (*session);
@@ -1156,11 +1131,6 @@ c_unparser::emit_module_init ()
 
   o->newline(-1) << "}";
 
-  if (! session->unprivileged) {
-    // Check whether the user is unprivileged.
-    o->newline() << "if (systemtap_unprivileged_user_check ()) rc = -EINVAL;";
-  }
-
   o->newline() << "if (rc) goto out;";
 
   // initialize gettimeofday (if needed)
@@ -5217,9 +5187,6 @@ translate_pass (systemtap_session& s)
       s.op->assert_0_indent();
 
       s.op->newline();
-      s.up->emit_unprivileged_user_check ();
-      s.op->assert_0_indent();
-      s.op->newline();
       s.up->emit_module_init ();
       s.op->assert_0_indent();
       s.op->newline();
diff --git a/translate.h b/translate.h
index 2c59a495..d1bff678 100644
--- a/translate.h
+++ b/translate.h
@@ -79,9 +79,6 @@ struct unparser
   virtual void emit_functionsig (functiondecl* v) = 0;
   // static void function_NAME (context* c);
 
-  virtual void emit_unprivileged_user_check () = 0;
-  // static void systemtap_check_unprivileged_user
-
   virtual void emit_module_init () = 0;
   virtual void emit_module_exit () = 0;
   // XXX
diff --git a/util.cxx b/util.cxx
index 5c05a1dd..a258bf72 100644
--- a/util.cxx
+++ b/util.cxx
@@ -51,6 +51,30 @@ get_home_directory(void)
 }
 
 
+// Get the size of a file in bytes
+size_t
+get_file_size(const string &path)
+{
+  struct stat file_info;
+
+  if (stat(path.c_str(), &file_info) == 0)
+    return file_info.st_size;
+  else
+    return 0;
+}
+
+// Get the size of a file in bytes
+bool
+file_exists (const string &path)
+{
+  struct stat file_info;
+
+  if (stat(path.c_str(), &file_info) == 0)
+    return true;
+
+  return false;
+}
+
 // Copy a file.  The copy is done via a temporary file and atomic
 // rename.
 int
diff --git a/util.h b/util.h
index 175f1f40..d249a71b 100644
--- a/util.h
+++ b/util.h
@@ -6,6 +6,8 @@
 #include <cctype>
 
 const char *get_home_directory(void);
+size_t get_file_size(const std::string &path);
+bool file_exists (const std::string &path);
 int copy_file(const char *src, const char *dest);
 int create_dir(const char *dir);
 int remove_file_or_dir(const char *dir);