Add libconnectivity_native
The library provides an interface to interface with the
ConnectivityNative service, and implement port blocking APIs.
Bug: 179733303
Test: atest connectivity_native_test
Change-Id: Iad1c84b5eeab835aca14a2db72a900e099aa3c1c
diff --git a/service/libconnectivity/include/connectivity_native.h b/service/libconnectivity/include/connectivity_native.h
new file mode 100644
index 0000000..5a2509a
--- /dev/null
+++ b/service/libconnectivity/include/connectivity_native.h
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#ifndef LIBCONNECTIVITY_CONNECTIVITY_NATIVE_H_
+#define LIBCONNECTIVITY_CONNECTIVITY_NATIVE_H_
+
+#include <sys/cdefs.h>
+#include <netinet/in.h>
+
+// For branches that do not yet have __ANDROID_API_U__ defined, like module
+// release branches.
+#ifndef __ANDROID_API_U__
+#define __ANDROID_API_U__ 34
+#endif
+
+__BEGIN_DECLS
+
+/**
+ * Blocks a port from being assigned during bind(). The caller is responsible for updating
+ * /proc/sys/net/ipv4/ip_local_port_range with the port being blocked so that calls to connect()
+ * will not automatically assign one of the blocked ports.
+ * Will return success even if port was already blocked.
+ *
+ * Returns 0 on success, or a POSIX error code (see errno.h) on failure:
+ * - EINVAL for invalid port number
+ * - EPERM if the UID of the client doesn't have network stack permission
+ * - Other errors as per https://man7.org/linux/man-pages/man2/bpf.2.html
+ *
+ * @param port Int corresponding to port number.
+ */
+int AConnectivityNative_blockPortForBind(in_port_t port) __INTRODUCED_IN(__ANDROID_API_U__);
+
+/**
+ * Unblocks a port that has previously been blocked.
+ * Will return success even if port was already unblocked.
+ *
+ * Returns 0 on success, or a POSIX error code (see errno.h) on failure:
+ * - EINVAL for invalid port number
+ * - EPERM if the UID of the client doesn't have network stack permission
+ * - Other errors as per https://man7.org/linux/man-pages/man2/bpf.2.html
+ *
+ * @param port Int corresponding to port number.
+ */
+int AConnectivityNative_unblockPortForBind(in_port_t port) __INTRODUCED_IN(__ANDROID_API_U__);
+
+/**
+ * Unblocks all ports that have previously been blocked.
+ *
+ * Returns 0 on success, or a POSIX error code (see errno.h) on failure:
+ * - EINVAL for invalid port number
+ * - EPERM if the UID of the client doesn't have network stack permission
+ * - Other errors as per https://man7.org/linux/man-pages/man2/bpf.2.html
+ */
+int AConnectivityNative_unblockAllPortsForBind() __INTRODUCED_IN(__ANDROID_API_U__);
+
+/**
+ * Gets the list of ports that have been blocked.
+ *
+ * Returns 0 on success, or a POSIX error code (see errno.h) on failure:
+ * - EINVAL for invalid port number
+ * - EPERM if the UID of the client doesn't have network stack permission
+ * - Other errors as per https://man7.org/linux/man-pages/man2/bpf.2.html
+ *
+ * @param ports Array of ports that will be filled with the port numbers.
+ * @param count Pointer to the size of the ports array; the value will be set to the total number of
+ * blocked ports, which may be larger than the ports array that was filled.
+ */
+int AConnectivityNative_getPortsBlockedForBind(in_port_t *ports, size_t *count)
+ __INTRODUCED_IN(__ANDROID_API_U__);
+
+__END_DECLS
+
+
+#endif