1 files changed, 70 insertions, 0 deletions
diff --git a/src/msg/async/dpdk/IPChecksum.cc b/src/msg/async/dpdk/IPChecksum.cc
new file mode 100644
index 000000000..7a3253c1e
--- /dev/null
+++ b/src/msg/async/dpdk/IPChecksum.cc
@@ -0,0 +1,70 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+/*
+ * This file is open source software, licensed to you under the terms
+ * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership.  You may not use this file except in compliance with the License.
+ *
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+/*
+ * Copyright (C) 2014 Cloudius Systems, Ltd.
+ */
+
+#include <arpa/inet.h>
+#include "net.h"
+#include "IPChecksum.h"
+
+void checksummer::sum(const char* data, size_t len) {
+  auto orig_len = len;
+  if (odd) {
+    csum += uint8_t(*data++);
+    --len;
+  }
+  auto p64 = reinterpret_cast<const uint64_t*>(data);
+  while (len >= 8) {
+    csum += ntohq(*p64++);
+    len -= 8;
+  }
+  auto p16 = reinterpret_cast<const uint16_t*>(p64);
+  while (len >= 2) {
+    csum += ntohs(*p16++);
+    len -= 2;
+  }
+  auto p8 = reinterpret_cast<const uint8_t*>(p16);
+  if (len) {
+    csum += *p8++ << 8;
+    len -= 1;
+  }
+  odd ^= orig_len & 1;
+}
+
+uint16_t checksummer::get() const {
+  __int128 csum1 = (csum & 0xffffffffffffffff) + (csum >> 64);
+  uint64_t csum = (csum1 & 0xffffffffffffffff) + (csum1 >> 64);
+  csum = (csum & 0xffff) + ((csum >> 16) & 0xffff) + ((csum >> 32) & 0xffff) + (csum >> 48);
+  csum = (csum & 0xffff) + (csum >> 16);
+  csum = (csum & 0xffff) + (csum >> 16);
+  return htons(~csum);
+}
+
+void checksummer::sum(const Packet& p) {
+  for (auto&& f : p.fragments()) {
+    sum(f.base, f.size);
+  }
+}
+
+uint16_t ip_checksum(const void* data, size_t len) {
+  checksummer cksum;
+  cksum.sum(reinterpret_cast<const char*>(data), len);
+  return cksum.get();
+}