Extends ifaddrs for cases where the client cannot send RTM_GETLINK requests.

The previous implementation of getifaddrs() depended on RTM_GETLINK requests being allowed, returning an error otherwise. This change makes getifaddrs() attempt to get all necessary information from RTM_NEWADDR messages when RTM_NEWLINK messages are not available.

The code is functionally the same when RTM_GETLINK requests are allowed. When RTM_GETLINK requests are denied, only interfaces that have a network address are returned, and physical addresses for these interfaces remain unset.

In addition, this change updates the copyright notice because repohooks asked nicely.

Bug: 141455849
Test: atest bionic-unit-tests-static
Test: atest NetworkInterfaceTest
Test: Connect to Wi-Fi network
Test: Set up hotspot
Test: Cast from device
Test: Pair Bluetooth device
Test: Call getifaddrs() directly from within an app.
Test: Call NetworkInterface#getNetworkInterfaces() from within an app.

Change-Id: Ia47e037d181ca5df6d9fdae19b405cabfafc6b0f
diff --git a/libc/NOTICE b/libc/NOTICE
index e2afdbf..51b00ad 100644
--- a/libc/NOTICE
+++ b/libc/NOTICE
@@ -1096,6 +1096,34 @@
 
 -------------------------------------------------------------------
 
+Copyright (C) 2020 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in
+   the documentation and/or other materials provided with the
+   distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
+
+-------------------------------------------------------------------
+
 Copyright (c) 1980, 1983, 1988, 1993
    The Regents of the University of California.  All rights reserved.