Move createTunInterface to its own test file for use elsewhere.
Bug: 28362720
Test: test-only change. netd_{unit,integration}_test pass.
Change-Id: I89f7c922ae8f8a550db58938dacff92390cc1d0f
diff --git a/tests/tun_interface.cpp b/tests/tun_interface.cpp
new file mode 100644
index 0000000..ddbf0c7
--- /dev/null
+++ b/tests/tun_interface.cpp
@@ -0,0 +1,95 @@
+/*
+ * Copyright 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * 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.
+ *
+ * tun_interface.cpp - creates tun interfaces for testing purposes
+ */
+
+#include <fcntl.h>
+#include <netdb.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+#include <netutils/ifc.h>
+
+#include "tun_interface.h"
+
+#define TUN_DEV "/dev/tun"
+
+using android::base::StringPrintf;
+
+namespace android {
+namespace net {
+
+int TunInterface::init() {
+ // Generate a random ULA address pair.
+ arc4random_buf(&mSrcAddr, sizeof(mSrcAddr));
+ mSrcAddr.s6_addr[0] = 0xfd;
+ memcpy(&mDstAddr, &mSrcAddr, sizeof(mDstAddr));
+ mDstAddr.s6_addr[15] ^= 1;
+
+ // Convert the addresses to strings because that's what ifc_add_address takes.
+ char srcStr[INET6_ADDRSTRLEN], dstStr[INET6_ADDRSTRLEN];
+ sockaddr_in6 src6 = { .sin6_family = AF_INET6, .sin6_addr = mSrcAddr, };
+ sockaddr_in6 dst6 = { .sin6_family = AF_INET6, .sin6_addr = mDstAddr, };
+ int flags = NI_NUMERICHOST;
+ if (getnameinfo((sockaddr *) &src6, sizeof(src6), srcStr, sizeof(srcStr), NULL, 0, flags) ||
+ getnameinfo((sockaddr *) &dst6, sizeof(dst6), dstStr, sizeof(dstStr), NULL, 0, flags)) {
+ return -EINVAL;
+ }
+
+ // Create a tun interface with a name based on our PID.
+ mIfName = StringPrintf("netdtest%u", getpid());
+ struct ifreq ifr = {
+ .ifr_ifru = { .ifru_flags = IFF_TUN },
+ };
+ snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", mIfName.c_str());
+
+ mFd = open(TUN_DEV, O_RDWR | O_NONBLOCK | O_CLOEXEC);
+ if (mFd == -1) return -errno;
+
+ int ret = ioctl(mFd, TUNSETIFF, &ifr, sizeof(ifr));
+ if (ret == -1) {
+ ret = -errno;
+ close(mFd);
+ return ret;
+ }
+
+ if (ifc_add_address(ifr.ifr_name, srcStr, 64) ||
+ ifc_add_address(ifr.ifr_name, dstStr, 64)) {
+ ret = -errno;
+ close(mFd);
+ return ret;
+ }
+
+ return 0;
+}
+
+void TunInterface::destroy() {
+ if (mFd != -1) {
+ close(mFd);
+ mFd = -1;
+ }
+}
+
+} // namespace net
+} // namespace android