[NETD-BPF#1] Move libnetdutils to frameworks/libs/net/...

libnetdutils is referenced by netd.c and TrafficController.cpp, which
are going to be mainlined. Therefore, move libnetdutils to a common
place where both mainline module and platform code (Netd) can refer to.

Bug: 202086915
Test: build; flash; cd system/netd; atest
Ignore-AOSP-First: the netd change(same topic) would not automerge from
aosp.
No-Typo-Check: Clean code move with no other changes.
BYPASS_INCLUSIVE_LANGUAGE_REASON=Clean code move with no other changes.
Change-Id: I645bfe35f6543149c9a9f894cd4158d27a481abe
diff --git a/staticlibs/netd/libnetdutils/include/netdutils/InternetAddresses.h b/staticlibs/netd/libnetdutils/include/netdutils/InternetAddresses.h
new file mode 100644
index 0000000..d5cbe2b
--- /dev/null
+++ b/staticlibs/netd/libnetdutils/include/netdutils/InternetAddresses.h
@@ -0,0 +1,325 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#pragma once
+
+#include <netdb.h>
+#include <netinet/in.h>
+#include <stdint.h>
+#include <cstring>
+#include <limits>
+#include <string>
+
+#include "netdutils/NetworkConstants.h"
+
+namespace android {
+namespace netdutils {
+
+namespace internal_ {
+
+// A structure to hold data for dealing with Internet addresses (IPAddress) and
+// related types such as IPSockAddr and IPPrefix.
+struct compact_ipdata {
+    uint8_t family{AF_UNSPEC};
+    uint8_t cidrlen{0U};  // written and read in host-byte order
+    in_port_t port{0U};   // written and read in host-byte order
+    uint32_t scope_id{0U};
+    union {
+        in_addr v4;
+        in6_addr v6;
+    } ip{.v6 = IN6ADDR_ANY_INIT};  // written and read in network-byte order
+
+    // Classes that use compact_ipdata and this method should be sure to clear
+    // (i.e. zero or make uniform) any fields not relevant to the class.
+    friend bool operator==(const compact_ipdata& a, const compact_ipdata& b) {
+        if ((a.family != b.family) || (a.cidrlen != b.cidrlen) || (a.port != b.port) ||
+            (a.scope_id != b.scope_id)) {
+            return false;
+        }
+        switch (a.family) {
+            case AF_UNSPEC:
+                // After the above checks, two AF_UNSPEC objects can be
+                // considered equal, for convenience.
+                return true;
+            case AF_INET: {
+                const in_addr v4a = a.ip.v4;
+                const in_addr v4b = b.ip.v4;
+                return (v4a.s_addr == v4b.s_addr);
+            }
+            case AF_INET6: {
+                const in6_addr v6a = a.ip.v6;
+                const in6_addr v6b = b.ip.v6;
+                return IN6_ARE_ADDR_EQUAL(&v6a, &v6b);
+            }
+        }
+        return false;
+    }
+
+    // Classes that use compact_ipdata and this method should be sure to clear
+    // (i.e. zero or make uniform) any fields not relevant to the class.
+    friend bool operator!=(const compact_ipdata& a, const compact_ipdata& b) { return !(a == b); }
+
+    // Classes that use compact_ipdata and this method should be sure to clear
+    // (i.e. zero or make uniform) any fields not relevant to the class.
+    friend bool operator<(const compact_ipdata& a, const compact_ipdata& b) {
+        if (a.family != b.family) return (a.family < b.family);
+        switch (a.family) {
+            case AF_INET: {
+                const in_addr v4a = a.ip.v4;
+                const in_addr v4b = b.ip.v4;
+                if (v4a.s_addr != v4b.s_addr) return (ntohl(v4a.s_addr) < ntohl(v4b.s_addr));
+                break;
+            }
+            case AF_INET6: {
+                const in6_addr v6a = a.ip.v6;
+                const in6_addr v6b = b.ip.v6;
+                const int cmp = std::memcmp(v6a.s6_addr, v6b.s6_addr, IPV6_ADDR_LEN);
+                if (cmp != 0) return cmp < 0;
+                break;
+            }
+        }
+        if (a.cidrlen != b.cidrlen) return (a.cidrlen < b.cidrlen);
+        if (a.port != b.port) return (a.port < b.port);
+        return (a.scope_id < b.scope_id);
+    }
+};
+
+static_assert(AF_UNSPEC <= std::numeric_limits<uint8_t>::max(), "AF_UNSPEC value too large");
+static_assert(AF_INET <= std::numeric_limits<uint8_t>::max(), "AF_INET value too large");
+static_assert(AF_INET6 <= std::numeric_limits<uint8_t>::max(), "AF_INET6 value too large");
+static_assert(sizeof(compact_ipdata) == 24U, "compact_ipdata unexpectedly large");
+
+}  // namespace internal_
+
+struct AddrinfoDeleter {
+    void operator()(struct addrinfo* p) const {
+        if (p != nullptr) {
+            freeaddrinfo(p);
+        }
+    }
+};
+
+typedef std::unique_ptr<struct addrinfo, struct AddrinfoDeleter> ScopedAddrinfo;
+
+inline bool usesScopedIds(const in6_addr& ipv6) {
+    return (IN6_IS_ADDR_LINKLOCAL(&ipv6) || IN6_IS_ADDR_MC_LINKLOCAL(&ipv6));
+}
+
+class IPPrefix;
+class IPSockAddr;
+
+class IPAddress {
+  public:
+    static bool forString(const std::string& repr, IPAddress* ip);
+    static IPAddress forString(const std::string& repr) {
+        IPAddress ip;
+        if (!forString(repr, &ip)) return IPAddress();
+        return ip;
+    }
+
+    IPAddress() = default;
+    IPAddress(const IPAddress&) = default;
+    IPAddress(IPAddress&&) = default;
+
+    explicit IPAddress(const in_addr& ipv4)
+        : mData({AF_INET, IPV4_ADDR_BITS, 0U, 0U, {.v4 = ipv4}}) {}
+    explicit IPAddress(const in6_addr& ipv6)
+        : mData({AF_INET6, IPV6_ADDR_BITS, 0U, 0U, {.v6 = ipv6}}) {}
+    IPAddress(const in6_addr& ipv6, uint32_t scope_id)
+        : mData({AF_INET6,
+                 IPV6_ADDR_BITS,
+                 0U,
+                 // Sanity check: scoped_ids only for link-local addresses.
+                 usesScopedIds(ipv6) ? scope_id : 0U,
+                 {.v6 = ipv6}}) {}
+    IPAddress(const IPAddress& ip, uint32_t scope_id) : IPAddress(ip) {
+        mData.scope_id = (family() == AF_INET6 && usesScopedIds(mData.ip.v6)) ? scope_id : 0U;
+    }
+
+    IPAddress& operator=(const IPAddress&) = default;
+    IPAddress& operator=(IPAddress&&) = default;
+
+    constexpr sa_family_t family() const noexcept { return mData.family; }
+    constexpr uint32_t scope_id() const noexcept { return mData.scope_id; }
+
+    std::string toString() const noexcept;
+
+    friend std::ostream& operator<<(std::ostream& os, const IPAddress& ip) {
+        os << ip.toString();
+        return os;
+    }
+    friend bool operator==(const IPAddress& a, const IPAddress& b) { return (a.mData == b.mData); }
+    friend bool operator!=(const IPAddress& a, const IPAddress& b) { return (a.mData != b.mData); }
+    friend bool operator<(const IPAddress& a, const IPAddress& b) { return (a.mData < b.mData); }
+    friend bool operator>(const IPAddress& a, const IPAddress& b) { return (b.mData < a.mData); }
+    friend bool operator<=(const IPAddress& a, const IPAddress& b) { return (a < b) || (a == b); }
+    friend bool operator>=(const IPAddress& a, const IPAddress& b) { return (b < a) || (a == b); }
+
+  private:
+    friend class IPPrefix;
+    friend class IPSockAddr;
+
+    explicit IPAddress(const internal_::compact_ipdata& ipdata) : mData(ipdata) {
+        mData.port = 0U;
+        switch (mData.family) {
+            case AF_INET:
+                mData.cidrlen = IPV4_ADDR_BITS;
+                mData.scope_id = 0U;
+                break;
+            case AF_INET6:
+                mData.cidrlen = IPV6_ADDR_BITS;
+                if (usesScopedIds(ipdata.ip.v6)) mData.scope_id = ipdata.scope_id;
+                break;
+            default:
+                mData.cidrlen = 0U;
+                mData.scope_id = 0U;
+                break;
+        }
+    }
+
+    internal_::compact_ipdata mData{};
+};
+
+class IPPrefix {
+  public:
+    static bool forString(const std::string& repr, IPPrefix* prefix);
+    static IPPrefix forString(const std::string& repr) {
+        IPPrefix prefix;
+        if (!forString(repr, &prefix)) return IPPrefix();
+        return prefix;
+    }
+
+    IPPrefix() = default;
+    IPPrefix(const IPPrefix&) = default;
+    IPPrefix(IPPrefix&&) = default;
+
+    explicit IPPrefix(const IPAddress& ip) : mData(ip.mData) {}
+
+    // Truncate the IP address |ip| at length |length|. Lengths greater than
+    // the address-family-relevant maximum, along with negative values, are
+    // interpreted as if the address-family-relevant maximum had been given.
+    IPPrefix(const IPAddress& ip, int length);
+
+    IPPrefix& operator=(const IPPrefix&) = default;
+    IPPrefix& operator=(IPPrefix&&) = default;
+
+    constexpr sa_family_t family() const noexcept { return mData.family; }
+    IPAddress ip() const noexcept { return IPAddress(mData); }
+    in_addr addr4() const noexcept { return mData.ip.v4; }
+    in6_addr addr6() const noexcept { return mData.ip.v6; }
+    constexpr int length() const noexcept { return mData.cidrlen; }
+
+    bool isUninitialized() const noexcept;
+    std::string toString() const noexcept;
+
+    friend std::ostream& operator<<(std::ostream& os, const IPPrefix& prefix) {
+        os << prefix.toString();
+        return os;
+    }
+    friend bool operator==(const IPPrefix& a, const IPPrefix& b) { return (a.mData == b.mData); }
+    friend bool operator!=(const IPPrefix& a, const IPPrefix& b) { return (a.mData != b.mData); }
+    friend bool operator<(const IPPrefix& a, const IPPrefix& b) { return (a.mData < b.mData); }
+    friend bool operator>(const IPPrefix& a, const IPPrefix& b) { return (b.mData < a.mData); }
+    friend bool operator<=(const IPPrefix& a, const IPPrefix& b) { return (a < b) || (a == b); }
+    friend bool operator>=(const IPPrefix& a, const IPPrefix& b) { return (b < a) || (a == b); }
+
+  private:
+    internal_::compact_ipdata mData{};
+};
+
+// An Internet socket address.
+//
+// Cannot represent other types of socket addresses (e.g. UNIX socket address, et cetera).
+class IPSockAddr {
+  public:
+    // TODO: static forString
+
+    static IPSockAddr toIPSockAddr(const std::string& repr, in_port_t port) {
+        return IPSockAddr(IPAddress::forString(repr), port);
+    }
+    static IPSockAddr toIPSockAddr(const sockaddr& sa) {
+        switch (sa.sa_family) {
+            case AF_INET:
+                return IPSockAddr(*reinterpret_cast<const sockaddr_in*>(&sa));
+            case AF_INET6:
+                return IPSockAddr(*reinterpret_cast<const sockaddr_in6*>(&sa));
+            default:
+                return IPSockAddr();
+        }
+    }
+    static IPSockAddr toIPSockAddr(const sockaddr_storage& ss) {
+        return toIPSockAddr(*reinterpret_cast<const sockaddr*>(&ss));
+    }
+
+    IPSockAddr() = default;
+    IPSockAddr(const IPSockAddr&) = default;
+    IPSockAddr(IPSockAddr&&) = default;
+
+    explicit IPSockAddr(const IPAddress& ip) : mData(ip.mData) {}
+    IPSockAddr(const IPAddress& ip, in_port_t port) : mData(ip.mData) { mData.port = port; }
+    explicit IPSockAddr(const sockaddr_in& ipv4sa)
+        : IPSockAddr(IPAddress(ipv4sa.sin_addr), ntohs(ipv4sa.sin_port)) {}
+    explicit IPSockAddr(const sockaddr_in6& ipv6sa)
+        : IPSockAddr(IPAddress(ipv6sa.sin6_addr, ipv6sa.sin6_scope_id), ntohs(ipv6sa.sin6_port)) {}
+
+    IPSockAddr& operator=(const IPSockAddr&) = default;
+    IPSockAddr& operator=(IPSockAddr&&) = default;
+
+    constexpr sa_family_t family() const noexcept { return mData.family; }
+    IPAddress ip() const noexcept { return IPAddress(mData); }
+    constexpr in_port_t port() const noexcept { return mData.port; }
+
+    // Implicit conversion to sockaddr_storage.
+    operator sockaddr_storage() const noexcept {
+        sockaddr_storage ss;
+        ss.ss_family = mData.family;
+        switch (mData.family) {
+            case AF_INET:
+                reinterpret_cast<sockaddr_in*>(&ss)->sin_addr = mData.ip.v4;
+                reinterpret_cast<sockaddr_in*>(&ss)->sin_port = htons(mData.port);
+                break;
+            case AF_INET6:
+                reinterpret_cast<sockaddr_in6*>(&ss)->sin6_addr = mData.ip.v6;
+                reinterpret_cast<sockaddr_in6*>(&ss)->sin6_port = htons(mData.port);
+                reinterpret_cast<sockaddr_in6*>(&ss)->sin6_scope_id = mData.scope_id;
+                break;
+        }
+        return ss;
+    }
+
+    std::string toString() const noexcept;
+
+    friend std::ostream& operator<<(std::ostream& os, const IPSockAddr& prefix) {
+        os << prefix.toString();
+        return os;
+    }
+    friend bool operator==(const IPSockAddr& a, const IPSockAddr& b) {
+        return (a.mData == b.mData);
+    }
+    friend bool operator!=(const IPSockAddr& a, const IPSockAddr& b) {
+        return (a.mData != b.mData);
+    }
+    friend bool operator<(const IPSockAddr& a, const IPSockAddr& b) { return (a.mData < b.mData); }
+    friend bool operator>(const IPSockAddr& a, const IPSockAddr& b) { return (b.mData < a.mData); }
+    friend bool operator<=(const IPSockAddr& a, const IPSockAddr& b) { return (a < b) || (a == b); }
+    friend bool operator>=(const IPSockAddr& a, const IPSockAddr& b) { return (b < a) || (a == b); }
+
+  private:
+    internal_::compact_ipdata mData{};
+};
+
+}  // namespace netdutils
+}  // namespace android