dart:io | Enable multithreaded secure networking encryption.

runtime/bin/secure_socket.cc

Index: runtime/bin/secure_socket.cc
diff --git a/runtime/bin/secure_socket.cc b/runtime/bin/secure_socket.cc
index 4310aec44fc46eae40591b3963836fb30206703f..0d2a76330c47acef983a80ceb9b5bfd0db259836 100644
--- a/runtime/bin/secure_socket.cc
+++ b/runtime/bin/secure_socket.cc
@@ -40,6 +40,13 @@ dart::Mutex SSLFilter::mutex_;  // To protect library initialization.
 // be null if only secure client sockets are used.
 const char* SSLFilter::password_ = NULL;
 
+// Forward declaration.
+static void ProcessFilter(Dart_Port dest_port_id,
+                          Dart_Port reply_port_id,
+                          Dart_CObject* message);
+
+NativeService SSLFilter::filter_service_("FilterService", ProcessFilter, 16);
+
 static const int kSSLFilterNativeFieldIndex = 0;
 
 static SSLFilter* GetFilter(Dart_NativeArguments args) {
@@ -161,22 +168,6 @@ void FUNCTION_NAME(SecureSocket_RegisterBadCertificateCallback)(
 }
 
 
-void FUNCTION_NAME(SecureSocket_ProcessBuffer)(Dart_NativeArguments args) {
-  Dart_EnterScope();
-  Dart_Handle buffer_id_object = ThrowIfError(Dart_GetNativeArgument(args, 1));
-  int64_t buffer_id = DartUtils::GetIntegerValue(buffer_id_object);
-  if (buffer_id < 0 || buffer_id >= SSLFilter::kNumBuffers) {
-    Dart_ThrowException(DartUtils::NewDartArgumentError(
-        "Illegal argument to ProcessBuffer"));
-  }
-
-  intptr_t bytes_read =
-      GetFilter(args)->ProcessBuffer(static_cast<int>(buffer_id));
-  Dart_SetReturnValue(args, Dart_NewInteger(bytes_read));
-  Dart_ExitScope();
-}
-
-
 void FUNCTION_NAME(SecureSocket_InitializeLibrary)
     (Dart_NativeArguments args) {
   Dart_EnterScope();
@@ -231,6 +222,110 @@ void FUNCTION_NAME(SecureSocket_PeerCertificate)
 }
 
 
+void FUNCTION_NAME(SecureSocket_FilterPointer)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  intptr_t filter_pointer = reinterpret_cast<intptr_t>(GetFilter(args));
+  Dart_SetReturnValue(args, Dart_NewInteger(filter_pointer));
+  Dart_ExitScope();
+}
+
+
+/**

[Søren Gjesse, 2013/06/17 07:31:07]

Nice comment

[Bill Hesse, 2013/06/20 14:56:26]

Thanks a lot

+ * Pushes data through the SSL filter, reading and writing from circular
+ * buffers shared with Dart.
+ *
+ * The Dart _SecureFilterImpl class contains 4 ExternalByteArrays used to
+ * pass encrypted and plaintext data to and from the C++ SSLFilter object.
+ *
+ * ProcessFilter is called with a CObject array containing the pointer to
+ * the SSLFilter, encoded as an int, and the start and end positions of the
+ * valid data in the four circular buffers.  The function only reads from
+ * the valid data area of the input buffers, and only writes to the free
+ * area of the output buffers.  The function returns the new start and end
+ * positions in the buffers, but it only updates start for input buffers, and
+ * end for output buffers.  Therefore, the Dart thread can simultaneously
+ * write to the free space and end pointer of input buffers, and read from
+ * the data space of output buffers, and modify the start pointer.
+ *
+ * When ProcessFilter returns, the Dart thread is responsible for combining
+ * the updated pointers from Dart and C++, to make the new valid state of
+ * the circular buffer.
+ */
+static void ProcessFilter(Dart_Port dest_port_id,
+                          Dart_Port reply_port_id,
+                          Dart_CObject* message) {
+  CObjectArray args(message);
+  CObjectIntptr filter_object(args[0]);
+  SSLFilter* filter = reinterpret_cast<SSLFilter*>(filter_object.Value());
+  bool in_handshake = CObjectBool(args[1]).Value();
+  int starts[SSLFilter::kNumBuffers];
+  int ends[SSLFilter::kNumBuffers];
+  for (int i = 0; i < SSLFilter::kNumBuffers; ++i) {
+    starts[i] = CObjectInt32(args[2*i + 2]).Value();

[Søren Gjesse, 2013/06/17 07:31:07]

We normally have space around all binary operators.

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+    ends[i] = CObjectInt32(args[2*i + 3]).Value();
+  }
+
+  filter->ProcessAllBuffers(starts, ends, in_handshake);
+
+  for (int i = 0; i < SSLFilter::kNumBuffers; ++i) {

[Søren Gjesse, 2013/06/17 07:31:07]

You could "cheat" here and just update the int value of the existing
Dart_CObjects instead of allocating new ones. You are already re-using the
request array.

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+    args.SetAt(2*i + 2, new CObjectInt32(CObject::NewInt32(starts[i])));
+    args.SetAt(2*i + 3, new CObjectInt32(CObject::NewInt32(ends[i])));
+  }
+  Dart_PostCObject(reply_port_id, args.AsApiCObject());
+}
+
+
+void SSLFilter::ProcessAllBuffers(int starts[kNumBuffers],
+                                  int ends[kNumBuffers],
+                                  bool in_handshake) {
+  for (int i = 0; i < kNumBuffers; ++i) {
+    if (in_handshake && (i == kReadPlaintext || i == kWritePlaintext)) continue;
+    int start = starts[i];
+    int end = ends[i];
+    int size = isBufferEncrypted(i) ? encrypted_buffer_size_ : buffer_size_;
+    switch (i) {
+      case kReadPlaintext:
+      case kWriteEncrypted:

[Søren Gjesse, 2013/06/17 07:31:07]

Maybe add an overall comment here: "Write data to buffer free space".

Also document that if the buffer is already full nothing will happen. Maybe add
an initial for full buffer and just continue in that case.

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+        if (start <= end) {

[Søren Gjesse, 2013/06/17 07:31:07]

If start == 0 this is not two segments after all.

[Bill Hesse, 2013/06/20 14:56:26]

 Or if it equals 1.  I think the comments are enough now.

+          // Free space is split into two segments.

[Søren Gjesse, 2013/06/17 07:31:07]

Please explain the "or" (when is the last element not incuded).

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+          // The first is [end, size - 1) or [end, size).
+          int buffer_end = (start == 0) ? size - 1 : size;
+          int bytes = ProcessBuffer(i, end, buffer_end);
+          end += bytes;
+          ASSERT(end <= size);
+          if (end == size) end = 0;
+        }
+        if (start > end + 1) {
+          int bytes = ProcessBuffer(i, end, start - 1);
+          end += bytes;
+          ASSERT(end < start);
+        }
+        ends[i] = end;
+        break;
+      case kReadEncrypted:
+      case kWritePlaintext:

[Søren Gjesse, 2013/06/17 07:31:07]

Overall comment here: "Read data from buffer"

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+        if (end < start) {
+          // Data is split into two segments.
+          // The first is [start, size).
+          int bytes = ProcessBuffer(i, start, size);
+          start += bytes;
+          ASSERT(start <= size);
+          if (start == size) start = 0;
+        }
+        if (start < end) {
+          int bytes = ProcessBuffer(i, start, end);
+          start += bytes;
+          ASSERT(start <= end);
+        }
+        starts[i] = start;
+        break;
+      default:
+        UNREACHABLE();
+    }
+  }
+}
+
+
 static Dart_Handle X509FromCertificate(CERTCertificate* certificate) {
   PRTime start_validity;
   PRTime end_validity;
@@ -291,15 +386,13 @@ void SSLFilter::InitializeBuffers(Dart_Handle dart_this) {
   // Create SSLFilter buffers as ExternalUint8Array objects.
   Dart_Handle dart_buffers_object = ThrowIfError(
       Dart_GetField(dart_this, DartUtils::NewString("buffers")));
-  Dart_Handle dart_buffer_object =
-      Dart_ListGetAt(dart_buffers_object, kReadPlaintext);
-  Dart_Handle external_buffer_class =
-      Dart_InstanceGetClass(dart_buffer_object);
+  Dart_Handle secure_filter_impl_class =
+      Dart_InstanceGetClass(dart_this);
   Dart_Handle dart_buffer_size = ThrowIfError(
-      Dart_GetField(external_buffer_class, DartUtils::NewString("SIZE")));
+      Dart_GetField(secure_filter_impl_class, DartUtils::NewString("SIZE")));
   int64_t buffer_size = DartUtils::GetIntegerValue(dart_buffer_size);
   Dart_Handle dart_encrypted_buffer_size = ThrowIfError(
-      Dart_GetField(external_buffer_class,
+      Dart_GetField(secure_filter_impl_class,
                     DartUtils::NewString("ENCRYPTED_SIZE")));
   int64_t encrypted_buffer_size =
       DartUtils::GetIntegerValue(dart_encrypted_buffer_size);
@@ -317,7 +410,7 @@ void SSLFilter::InitializeBuffers(Dart_Handle dart_this) {
 
   Dart_Handle data_identifier = DartUtils::NewString("data");
   for (int i = 0; i < kNumBuffers; ++i) {
-    int size = isEncrypted(i) ? encrypted_buffer_size_ : buffer_size_;
+    int size = isBufferEncrypted(i) ? encrypted_buffer_size_ : buffer_size_;
     dart_buffer_objects_[i] =
         Dart_NewPersistentHandle(Dart_ListGetAt(dart_buffers_object, i));
     ASSERT(dart_buffer_objects_[i] != NULL);
@@ -626,106 +719,102 @@ void SSLFilter::Destroy() {
 }
 
 
-intptr_t SSLFilter::ProcessBuffer(int buffer_index) {
-  int size = isEncrypted(buffer_index) ? encrypted_buffer_size_ : buffer_size_;
-  Dart_Handle buffer_object =
-      Dart_HandleFromPersistent(dart_buffer_objects_[buffer_index]);
-  Dart_Handle start_object = ThrowIfError(
-      Dart_GetField(buffer_object, Dart_HandleFromPersistent(string_start_)));
-  Dart_Handle length_object = ThrowIfError(
-      Dart_GetField(buffer_object, Dart_HandleFromPersistent(string_length_)));
-  int64_t unsafe_start = DartUtils::GetIntegerValue(start_object);
-  int64_t unsafe_length = DartUtils::GetIntegerValue(length_object);
-  ASSERT(unsafe_start >= 0);
-  ASSERT(unsafe_start < size);
-  ASSERT(unsafe_length >= 0);
-  ASSERT(unsafe_length <= size);
-  int start = static_cast<int>(unsafe_start);
-  int length = static_cast<int>(unsafe_length);
-  uint8_t* buffer = buffers_[buffer_index];
-
+intptr_t SSLFilter::ProcessBuffer(int buffer_index, int start, int end) {

[Søren Gjesse, 2013/06/17 07:31:07]

You don't need for this CL, but how about just splitting this function into for
functions:

  ProcessWritePlaintext
  ProcessReadPlaintext
  ...

And calling each of these from ProcessAllBuffers?

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+  int length = end - start;
   int bytes_processed = 0;
-  switch (buffer_index) {
-    case kReadPlaintext: {
-      int bytes_free = size - start - length;
-      bytes_processed = PR_Read(filter_,
-                                buffer + start + length,
-                                bytes_free);
-      if (bytes_processed < 0) {
-        ASSERT(bytes_processed == -1);
-        // TODO(whesse): Handle unexpected errors here.
-        PRErrorCode pr_error = PR_GetError();
-        if (PR_WOULD_BLOCK_ERROR != pr_error) {
-          ThrowPRException("Error reading plaintext from SSLFilter");
+  // The kWritePlaintext case must be called to push data through the filter.
+  if (length > 0 || buffer_index == kWritePlaintext) {
+    uint8_t* buffer = buffers_[buffer_index];
+    switch (buffer_index) {
+      case kReadPlaintext: {
+        bytes_processed = PR_Read(filter_,
+                                  buffer + start,
+                                  length);
+        if (bytes_processed < 0) {
+          ASSERT(bytes_processed == -1);
+          // TODO(whesse): Handle unexpected errors here.
+          PRErrorCode pr_error = PR_GetError();
+          if (PR_WOULD_BLOCK_ERROR != pr_error) {
+            // TODO(whesse): Handle errors

[Søren Gjesse, 2013/06/17 07:31:07]

Please open an issue on this.

[Bill Hesse, 2013/06/20 14:56:26]

Done.

+            FATAL("Error reading plaintext from SSLFilter");
+          }
+          bytes_processed = 0;
         }
-        bytes_processed = 0;
+        break;
       }
-      break;
-    }
 
-    case kWriteEncrypted: {
-      const uint8_t* buf1;
-      const uint8_t* buf2;
-      unsigned int len1;
-      unsigned int len2;
-      int bytes_free = size - start - length;
-      memio_Private* secret = memio_GetSecret(filter_);
-      memio_GetWriteParams(secret, &buf1, &len1, &buf2, &len2);
-      int bytes_to_send =
-          dart::Utils::Minimum(len1, static_cast<unsigned>(bytes_free));
-      if (bytes_to_send > 0) {
-        memmove(buffer + start + length, buf1, bytes_to_send);
-        bytes_processed = bytes_to_send;
-      }
-      bytes_to_send = dart::Utils::Minimum(len2,
-          static_cast<unsigned>(bytes_free - bytes_processed));
-      if (bytes_to_send > 0) {
-        memmove(buffer + start + length + bytes_processed, buf2,
-                bytes_to_send);
-        bytes_processed += bytes_to_send;
-      }
-      if (bytes_processed > 0) {
-        memio_PutWriteResult(secret, bytes_processed);
+      case kWriteEncrypted: {
+        const uint8_t* buf1;
+        const uint8_t* buf2;
+        unsigned int len1;
+        unsigned int len2;
+        memio_Private* secret = memio_GetSecret(filter_);
+        memio_GetWriteParams(secret, &buf1, &len1, &buf2, &len2);
+        int bytes_to_send =
+            dart::Utils::Minimum(len1, static_cast<unsigned>(length));
+        if (bytes_to_send > 0) {
+          memmove(buffer + start, buf1, bytes_to_send);
+          bytes_processed = bytes_to_send;
+        }
+        bytes_to_send = dart::Utils::Minimum(len2,
+            static_cast<unsigned>(length - bytes_processed));
+        if (bytes_to_send > 0) {
+          memmove(buffer + start + bytes_processed, buf2, bytes_to_send);
+          bytes_processed += bytes_to_send;
+        }
+        if (bytes_processed > 0) {
+          memio_PutWriteResult(secret, bytes_processed);
+        }
+        break;
       }
-      break;
-    }
 
-    case kReadEncrypted: {
-      if (length > 0) {
-        bytes_processed = length;
+      case kReadEncrypted: {
         memio_Private* secret = memio_GetSecret(filter_);
         uint8_t* filter_buf;
         int free_bytes = memio_GetReadParams(secret, &filter_buf);
-        if (free_bytes < bytes_processed) bytes_processed = free_bytes;
-        memmove(filter_buf,
-                buffer + start,
-                bytes_processed);
+        bytes_processed = dart::Utils::Minimum(length, free_bytes);
+        memmove(filter_buf, buffer + start, bytes_processed);
         memio_PutReadResult(secret, bytes_processed);
-      }
-      break;
-    }
-
-    case kWritePlaintext: {
-      if (length > 0) {
-        bytes_processed = PR_Write(filter_,
-                                   buffer + start,
-                                   length);
+        break;
       }
 
-      if (bytes_processed < 0) {
-        ASSERT(bytes_processed == -1);
-        // TODO(whesse): Handle unexpected errors here.
-        PRErrorCode pr_error = PR_GetError();
-        if (PR_WOULD_BLOCK_ERROR != pr_error) {
-          ThrowPRException("Error reading plaintext from SSLFilter");
+      case kWritePlaintext: {
+        bytes_processed = PR_Write(filter_, buffer + start, length);
+        if (bytes_processed < 0) {
+          ASSERT(bytes_processed == -1);
+          // TODO(whesse): Handle unexpected errors here.
+          PRErrorCode pr_error = PR_GetError();
+          if (PR_WOULD_BLOCK_ERROR != pr_error) {
+            // TODO(whesse): Handle errors
+            FATAL("Error reading plaintext from SSLFilter");
+          }
+          bytes_processed = 0;
         }
-        bytes_processed = 0;
+        break;
       }
-      break;
     }
   }
   return bytes_processed;
 }
 
+
+Dart_Port SSLFilter::GetServicePort() {
+  return filter_service_.GetServicePort();
+}
+
+
+void FUNCTION_NAME(SecureSocket_NewServicePort)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  Dart_SetReturnValue(args, Dart_Null());
+  Dart_Port service_port = SSLFilter::GetServicePort();
+  if (service_port != ILLEGAL_PORT) {
+    // Return a send port for the service port.
+    Dart_Handle send_port = Dart_NewSendPort(service_port);
+    Dart_SetReturnValue(args, send_port);
+  }
+  Dart_ExitScope();
+}
+
+
 }  // namespace bin
 }  // namespace dart