1. Create a new sandbox type which allows access to Unix sockets in the Mac

renderer sandbox to support running Native Client.
2. Put the Native Client sel_ldr (which contains the user's untrusted code)
into a new Mac sandbox type.
3. Open /dev/random in SandboxWarmup().
4. Remove the "--nosandbox" flag when running Mac tests.

See http://codereview.chromium.org/1234003/show and
http://codereview.chromium.org/1525005/show which were both reverted because
of problems on Mac 10.6. This change is identical except for the ";NACL"
lines in renderer.sb files and the corresponding lines in nacl-loader.sb.
Unix socket support for the sandbox changed considerably from 10.5 to 10.6.

BUG=http://code.google.com/p/nativeclient/issues/detail?id=327
TEST=nacl_ui_tests still pass while running in the sandbox.

Review URL: http://codereview.chromium.org/1559012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@43473 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 62 insertions, 5 deletions

diff --git a/chrome/common/sandbox_init_wrapper_mac.cc b/chrome/common/sandbox_init_wrapper_mac.cc
index 898faed..3ed61ed 100644
--- a/chrome/common/sandbox_init_wrapper_mac.cc
+++ b/chrome/common/sandbox_init_wrapper_mac.cc
@@ -20,8 +20,17 @@ bool SandboxInitWrapper::InitializeSandbox(const CommandLine& command_line,
     // Browser process isn't sandboxed.
     return true;
   } else if (process_type == switches::kRendererProcess) {
-    // Renderer process sandbox.
-    sandbox_process_type = sandbox::SANDBOX_TYPE_RENDERER;
+    // Renderer process sandbox. If --internal_nacl is present then use the
+    // version of the renderer sandbox which allows Native Client to use Unix
+    // sockets.
+    // TODO(msneck): Remove the use of Unix sockets from Native Client and
+    // then get rid of the SANDBOX_TYPE_NACL_PLUGIN enum.
+    // See http://code.google.com/p/nativeclient/issues/detail?id=344
+    if (command_line.HasSwitch(switches::kInternalNaCl)) {
+      sandbox_process_type = sandbox::SANDBOX_TYPE_NACL_PLUGIN;
+    } else {
+      sandbox_process_type = sandbox::SANDBOX_TYPE_RENDERER;
+    }
   } else if (process_type == switches::kExtensionProcess) {
     // Extension processes are just renderers [they use RenderMain()] with a
     // different set of command line flags.
@@ -39,8 +48,10 @@ bool SandboxInitWrapper::InitializeSandbox(const CommandLine& command_line,
   } else if (process_type == switches::kWorkerProcess) {
     // Worker process sandbox.
     sandbox_process_type = sandbox::SANDBOX_TYPE_WORKER;
-  } else if ((process_type == switches::kNaClLoaderProcess) ||
-             (process_type == switches::kPluginProcess) ||
+  } else if (process_type == switches::kNaClLoaderProcess) {
+    // Native Client sel_ldr (user untrusted code) sandbox.
+    sandbox_process_type = sandbox::SANDBOX_TYPE_NACL_LOADER;
+  } else if ((process_type == switches::kPluginProcess) ||
              (process_type == switches::kProfileImportProcess) ||
              (process_type == switches::kGpuProcess)) {
     return true;
diff --git a/chrome/common/sandbox_mac.h b/chrome/common/sandbox_mac.h
index a8a55b0..c8ef4c3 100644
--- a/chrome/common/sandbox_mac.h
+++ b/chrome/common/sandbox_mac.h
@@ -12,12 +12,20 @@ namespace sandbox {
 enum SandboxProcessType {
   SANDBOX_TYPE_RENDERER,
 
-  // Worker process has *everything* not needed for Cocoa locked down.
+  // The worker processes uses the most restrictive sandbox which has almost
+  // *everything* locked down. Only a couple of /System/Library/ paths and
+  // some other very basic operations (e.g., reading metadata to allow
+  // following symlinks) are permitted.
   SANDBOX_TYPE_WORKER,
 
   // Utility process is as restrictive as the worker process except full access
   // is allowed to one configurable directory.
   SANDBOX_TYPE_UTILITY,
+
+  // Native Client sandboxes. The plugin contains trusted code and the
+  // loader contains the user's untrusted code.
+  SANDBOX_TYPE_NACL_PLUGIN,
+  SANDBOX_TYPE_NACL_LOADER,
 };
 
 // Warm up System APIs that empirically need to be accessed before the Sandbox
diff --git a/chrome/common/sandbox_mac.mm b/chrome/common/sandbox_mac.mm
index ca8ac6c..1299481 100644
--- a/chrome/common/sandbox_mac.mm
+++ b/chrome/common/sandbox_mac.mm
@@ -15,6 +15,7 @@ extern "C" {
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/mac_util.h"
+#include "base/rand_util_c.h"
 #include "base/scoped_cftyperef.h"
 #include "base/scoped_nsautorelease_pool.h"
 #include "base/string16.h"
@@ -234,6 +235,10 @@ void SandboxWarmup() {
         NULL));
     CGImageSourceGetStatus(img);
   }
+
+  { // Native Client access to /dev/random.
+    GetUrandomFD();
+  }
 }
 
 // Turns on the OS X sandbox for this process.
@@ -250,6 +255,7 @@ bool EnableSandbox(SandboxProcessType sandbox_type,
   // TODO(jeremy): Look at using include syntax to unify common parts of sandbox
   // definition files.
   NSString* sandbox_config_filename = nil;
+  bool allow_nacl_lines = false;
   switch (sandbox_type) {
     case SANDBOX_TYPE_RENDERER:
       sandbox_config_filename = @"renderer";
@@ -260,6 +266,26 @@ bool EnableSandbox(SandboxProcessType sandbox_type,
     case SANDBOX_TYPE_UTILITY:
       sandbox_config_filename = @"utility";
       break;
+    case SANDBOX_TYPE_NACL_PLUGIN:
+      // The Native Client plugin is a standard renderer sandbox with some
+      // additional lines to support use of Unix sockets.
+      // TODO(msneck): Remove the use of Unix sockets from Native Client and
+      // then remove the associated rules from chrome/renderer/renderer.sb.
+      // See http://code.google.com/p/nativeclient/issues/detail?id=344
+      sandbox_config_filename = @"renderer";
+      allow_nacl_lines = true;
+      break;
+    case SANDBOX_TYPE_NACL_LOADER:
+      // The Native Client loader is used for safeguarding the user's
+      // untrusted code within Native Client.
+      // TODO(msneck): Remove the use of Unix sockets from Native Client and
+      // then decide on an appropriate sandbox type for the untrusted code.
+      // This might simply mean removing the Unix socket rules from
+      // chrome/browser/nacl-loader.sb or it might mean sharing the
+      // sandbox configuration with SANDBOX_TYPE_WORKER.
+      // See http://code.google.com/p/nativeclient/issues/detail?id=344
+      sandbox_config_filename = @"nacl-loader";
+      break;
     default:
       NOTREACHED();
       return false;
@@ -288,6 +314,13 @@ bool EnableSandbox(SandboxProcessType sandbox_type,
                                   withString:@""];
   }
 
+  // Enable Native Client lines if they are allowed.
+  if (allow_nacl_lines) {
+    sandbox_data = [sandbox_data
+        stringByReplacingOccurrencesOfString:@";NACL"
+                                  withString:@""];
+  }
+
   if (!allowed_dir.empty()) {
     // The sandbox only understands "real" paths.  This resolving step is
     // needed so the caller doesn't need to worry about things like /var
@@ -341,6 +374,11 @@ bool EnableSandbox(SandboxProcessType sandbox_type,
     sandbox_data = [sandbox_data
         stringByReplacingOccurrencesOfString:@"USER_HOMEDIR"
                                   withString:home_dir_escaped_ns];
+  } else if (major_version == 10 && minor_version < 6) {
+    // Sandbox rules only for versions before 10.6.
+    sandbox_data = [sandbox_data
+        stringByReplacingOccurrencesOfString:@";BEFORE_10.6"
+                                  withString:@""];
   }
 
   char* error_buff = NULL;