Add sandbox support for associating peer processes

TEST=HandlePolicyTest.DuplicatePeerHandle

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=131940
Review URL: https://chromiumcodereview.appspot.com/9960045

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@132112 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 138 insertions, 13 deletions

diff --git a/sandbox/src/broker_services.cc b/sandbox/src/broker_services.cc
index d361c2e..5ee5620 100644
--- a/sandbox/src/broker_services.cc
+++ b/sandbox/src/broker_services.cc
@@ -41,11 +41,33 @@ sandbox::ResultCode SpawnCleanup(sandbox::TargetProcess* target, DWORD error) {
 // executes TargetEventsThread().
 enum {
   THREAD_CTRL_NONE,
+  THREAD_CTRL_REMOVE_PEER,
   THREAD_CTRL_QUIT,
-  THREAD_CTRL_LAST
+  THREAD_CTRL_LAST,
 };
 
-}
+// Helper structure that allows the Broker to associate a job notification
+// with a job object and with a policy.
+struct JobTracker {
+  HANDLE job;
+  sandbox::PolicyBase* policy;
+  JobTracker(HANDLE cjob, sandbox::PolicyBase* cpolicy)
+      : job(cjob), policy(cpolicy) {
+  }
+};
+
+// Helper structure that allows the broker to track peer processes
+struct PeerTracker {
+  HANDLE wait_object;
+  base::win::ScopedHandle process;
+  DWORD id;
+  HANDLE job_port;
+  PeerTracker(DWORD process_id, HANDLE broker_job_port)
+      : wait_object(NULL), id(process_id), job_port(broker_job_port) {
+  }
+};
+
+}  // namespace
 
 namespace sandbox {
 
@@ -85,6 +107,7 @@ BrokerServicesBase::~BrokerServicesBase() {
   // If there is no port Init() was never called successfully.
   if (!job_port_)
     return;
+
   // Closing the port causes, that no more Job notifications are delivered to
   // the worker thread and also causes the thread to exit. This is what we
   // want to do since we are going to close all outstanding Jobs and notifying
@@ -107,6 +130,18 @@ BrokerServicesBase::~BrokerServicesBase() {
   ::CloseHandle(job_thread_);
   delete thread_pool_;
   ::CloseHandle(no_targets_);
+
+  // Cancel the wait events and delete remaining peer trackers.
+  for (PeerTrackerMap::iterator it = peer_map_.begin();
+       it != peer_map_.end(); ++it) {
+    // Deregistration shouldn't fail, but we leak rather than crash if it does.
+    if (::UnregisterWaitEx(it->second->wait_object, INVALID_HANDLE_VALUE)) {
+      delete it->second;
+    } else {
+      NOTREACHED();
+    }
+  }
+
   // If job_port_ isn't NULL, assumes that the lock has been initialized.
   if (job_port_)
     ::DeleteCriticalSection(&lock_);
@@ -209,9 +244,23 @@ DWORD WINAPI BrokerServicesBase::TargetEventsThread(PVOID param) {
         }
       }
 
+    } else if (THREAD_CTRL_REMOVE_PEER == key) {
+      // Remove a process from our list of peers.
+      AutoLock lock(&broker->lock_);
+      PeerTrackerMap::iterator it =
+          broker->peer_map_.find(reinterpret_cast<DWORD>(ovl));
+      // This shouldn't fail, but if it does leak the memory rather than crash.
+      if (::UnregisterWaitEx(it->second->wait_object, INVALID_HANDLE_VALUE)) {
+        delete it->second;
+        broker->peer_map_.erase(it);
+      } else {
+        NOTREACHED();
+      }
+
     } else if (THREAD_CTRL_QUIT == key) {
       // The broker object is being destroyed so the thread needs to exit.
       return 0;
+
     } else {
       // We have not implemented more commands.
       NOTREACHED();
@@ -312,7 +361,44 @@ ResultCode BrokerServicesBase::WaitForAllTargets() {
 
 bool BrokerServicesBase::IsActiveTarget(DWORD process_id) {
   AutoLock lock(&lock_);
-  return child_process_ids_.find(process_id) != child_process_ids_.end();
+  return child_process_ids_.find(process_id) != child_process_ids_.end() ||
+         peer_map_.find(process_id) != peer_map_.end();
+}
+
+VOID CALLBACK BrokerServicesBase::RemovePeer(PVOID parameter, BOOLEAN) {
+  PeerTracker* peer = reinterpret_cast<PeerTracker*>(parameter);
+  // Don't check the return code because we this may fail (safely) at shutdown.
+  ::PostQueuedCompletionStatus(peer->job_port, 0, THREAD_CTRL_REMOVE_PEER,
+                               reinterpret_cast<LPOVERLAPPED>(peer->id));
+}
+
+ResultCode BrokerServicesBase::AddTargetPeer(HANDLE peer_process) {
+  scoped_ptr<PeerTracker> peer(new PeerTracker(::GetProcessId(peer_process),
+                                               job_port_));
+  if (!peer->id)
+    return SBOX_ERROR_GENERIC;
+
+  if (!::DuplicateHandle(::GetCurrentProcess(), peer_process,
+                         ::GetCurrentProcess(), peer->process.Receive(),
+                         SYNCHRONIZE, FALSE, 0)) {
+    return SBOX_ERROR_GENERIC;
+  }
+
+  AutoLock lock(&lock_);
+  if (!peer_map_.insert(std::make_pair(peer->id, peer.get())).second)
+    return SBOX_ERROR_BAD_PARAMS;
+
+  if (!::RegisterWaitForSingleObject(&peer->wait_object,
+                                     peer->process, RemovePeer,
+                                     peer.get(), INFINITE, WT_EXECUTEONLYONCE |
+                                     WT_EXECUTEINWAITTHREAD)) {
+    peer_map_.erase(peer->id);
+    return SBOX_ERROR_GENERIC;
+  }
+
+  // Leak the pointer since it will be cleaned up by the callback.
+  peer.release();
+  return SBOX_ALL_OK;
 }
 
 }  // namespace sandbox
diff --git a/sandbox/src/broker_services.h b/sandbox/src/broker_services.h
index 8e4cb54..98760d9 100644
--- a/sandbox/src/broker_services.h
+++ b/sandbox/src/broker_services.h
@@ -6,8 +6,10 @@
 #define SANDBOX_SRC_BROKER_SERVICES_H__
 
 #include <list>
+#include <map>
 #include <set>
 #include "base/basictypes.h"
+#include "base/win/scoped_handle.h"
 #include "sandbox/src/crosscall_server.h"
 #include "sandbox/src/job.h"
 #include "sandbox/src/sandbox.h"
@@ -15,6 +17,13 @@
 #include "sandbox/src/win2k_threadpool.h"
 #include "sandbox/src/win_utils.h"
 
+namespace {
+
+struct JobTracker;
+struct PeerTracker;
+
+}  // namespace
+
 namespace sandbox {
 
 class PolicyBase;
@@ -45,6 +54,8 @@ class BrokerServicesBase : public BrokerServices,
 
   virtual ResultCode WaitForAllTargets();
 
+  virtual ResultCode AddTargetPeer(HANDLE peer_process);
+
   // Checks if the supplied process ID matches one of the broker's active
   // target processes
   // Returns:
@@ -52,16 +63,6 @@ class BrokerServicesBase : public BrokerServices,
   bool IsActiveTarget(DWORD process_id);
 
  private:
-  // Helper structure that allows the Broker to associate a job notification
-  // with a job object and with a policy.
-  struct JobTracker {
-    HANDLE job;
-    PolicyBase* policy;
-    JobTracker(HANDLE cjob, PolicyBase* cpolicy)
-        : job(cjob), policy(cpolicy) {
-     }
-  };
-
   // Releases the Job and notifies the associated Policy object to its
   // resources as well.
   static void FreeResources(JobTracker* tracker);
@@ -70,6 +71,9 @@ class BrokerServicesBase : public BrokerServices,
   // notifications and cleanup-related tasks.
   static DWORD WINAPI TargetEventsThread(PVOID param);
 
+  // Removes a target peer from the process list if it expires.
+  static VOID CALLBACK RemovePeer(PVOID parameter, BOOLEAN);
+
   // The completion port used by the job objects to communicate events to
   // the worker thread.
   HANDLE job_port_;
@@ -92,6 +96,11 @@ class BrokerServicesBase : public BrokerServices,
   typedef std::list<JobTracker*> JobTrackerList;
   JobTrackerList tracker_list_;
 
+  // Maps peer process IDs to the saved handle and wait event.
+  // Prevents peer callbacks from accessing the broker after destruction.
+  typedef std::map<DWORD, PeerTracker*> PeerTrackerMap;
+  PeerTrackerMap peer_map_;
+
   // Provides a fast lookup to identify sandboxed processes.
   std::set<DWORD> child_process_ids_;
 
diff --git a/sandbox/src/handle_policy_test.cc b/sandbox/src/handle_policy_test.cc
index bccca67..bb08b86 100644
--- a/sandbox/src/handle_policy_test.cc
+++ b/sandbox/src/handle_policy_test.cc
@@ -65,5 +65,27 @@ TEST(HandlePolicyTest, DuplicateHandle) {
   EXPECT_EQ(SBOX_TEST_SUCCEEDED, runner.RunTest(cmd_line.c_str()));
 }
 
+// Tests that duplicating an object works only when the policy allows it.
+TEST(HandlePolicyTest, DuplicatePeerHandle) {
+  TestRunner target;
+  TestRunner runner;
+
+  // Kick off an asynchronous target process for testing.
+  target.SetAsynchronous(true);
+  target.SetUnsandboxed(true);
+  EXPECT_EQ(SBOX_TEST_SUCCEEDED, target.RunTest(L"Handle_WaitProcess 30000"));
+
+  // First test that we fail to open the event.
+  std::wstring cmd_line = base::StringPrintf(L"Handle_DuplicateEvent %d",
+                                             target.process_id());
+  EXPECT_EQ(SBOX_TEST_DENIED, runner.RunTest(cmd_line.c_str()));
+
+  // Now successfully open the event after adding a duplicate handle rule.
+  EXPECT_TRUE(runner.AddRule(TargetPolicy::SUBSYS_HANDLES,
+                             TargetPolicy::HANDLES_DUP_ANY,
+                             L"Event"));
+  EXPECT_EQ(SBOX_TEST_SUCCEEDED, runner.RunTest(cmd_line.c_str()));
+}
+
 }  // namespace sandbox
 
diff --git a/sandbox/src/sandbox.h b/sandbox/src/sandbox.h
index 683bda7..18c05ce 100644
--- a/sandbox/src/sandbox.h
+++ b/sandbox/src/sandbox.h
@@ -84,6 +84,14 @@ class BrokerServices {
   //   If the return is ERROR_GENERIC, you can call ::GetLastError() to get
   //   more information.
   virtual ResultCode WaitForAllTargets() = 0;
+
+  // Adds an unsandboxed process as a peer for policy decisions (e.g.
+  // HANDLES_DUP_ANY policy).
+  // Returns:
+  //   ALL_OK if successful. All other return values imply failure.
+  //   If the return is ERROR_GENERIC, you can call ::GetLastError() to get
+  //   more information.
+  virtual ResultCode AddTargetPeer(HANDLE peer_process) = 0;
 };
 
 // TargetServices models the current process from the perspective