diff --git a/src/netaddress.h b/src/netaddress.h
index b8b46fe4d..f5d442801 100644
--- a/src/netaddress.h
+++ b/src/netaddress.h
@@ -1,202 +1,198 @@
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_NETADDRESS_H
 #define BITCOIN_NETADDRESS_H
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <compat.h>
 #include <serialize.h>
 #include <span.h>
 
 #include <cstdint>
 #include <string>
 #include <vector>
 
 enum Network {
     NET_UNROUTABLE = 0,
     NET_IPV4,
     NET_IPV6,
     NET_ONION,
     NET_INTERNAL,
 
     NET_MAX,
 };
 
 /** IP address (IPv6, or IPv4 using mapped IPv6 range (::FFFF:0:0/96)) */
 class CNetAddr {
 protected:
     // in network byte order
     uint8_t ip[16];
     // for scoped/link-local ipv6 addresses
     uint32_t scopeId{0};
 
 public:
     CNetAddr();
     explicit CNetAddr(const struct in_addr &ipv4Addr);
     void SetIP(const CNetAddr &ip);
 
 private:
     /**
      * Set raw IPv4 or IPv6 address (in network byte order)
      * @note Only NET_IPV4 and NET_IPV6 are allowed for network.
      */
     void SetRaw(Network network, const uint8_t *data);
 
 public:
     /**
      * Transform an arbitrary string into a non-routable ipv6 address.
      * Useful for mapping resolved addresses back to their source.
      */
     bool SetInternal(const std::string &name);
 
     // for Tor addresses
     bool SetSpecial(const std::string &strName);
     // IPv4 mapped address (::FFFF:0:0/96, 0.0.0.0/0)
     bool IsIPv4() const;
     // IPv6 address (not mapped IPv4, not Tor)
     bool IsIPv6() const;
     // IPv4 private networks (10.0.0.0/8, 192.168.0.0/16, 172.16.0.0/12)
     bool IsRFC1918() const;
     // IPv4 inter-network communications (192.18.0.0/15)
     bool IsRFC2544() const;
     // IPv4 ISP-level NAT (100.64.0.0/10)
     bool IsRFC6598() const;
     // IPv4 documentation addresses (192.0.2.0/24, 198.51.100.0/24,
     // 203.0.113.0/24)
     bool IsRFC5737() const;
     // IPv6 documentation address (2001:0DB8::/32)
     bool IsRFC3849() const;
     // IPv4 autoconfig (169.254.0.0/16)
     bool IsRFC3927() const;
     // IPv6 6to4 tunnelling (2002::/16)
     bool IsRFC3964() const;
     // IPv6 unique local (FC00::/7)
     bool IsRFC4193() const;
     // IPv6 Teredo tunnelling (2001::/32)
     bool IsRFC4380() const;
     // IPv6 ORCHID (2001:10::/28)
     bool IsRFC4843() const;
     // IPv6 autoconfig (FE80::/64)
     bool IsRFC4862() const;
     // IPv6 well-known prefix (64:FF9B::/96)
     bool IsRFC6052() const;
     // IPv6 IPv4-translated address (::FFFF:0:0:0/96)
     bool IsRFC6145() const;
     bool IsTor() const;
     bool IsLocal() const;
     bool IsRoutable() const;
     bool IsInternal() const;
     bool IsValid() const;
     enum Network GetNetwork() const;
     std::string ToString() const;
     std::string ToStringIP() const;
     unsigned int GetByte(int n) const;
     uint64_t GetHash() const;
     bool GetInAddr(struct in_addr *pipv4Addr) const;
     std::vector<uint8_t> GetGroup() const;
     int GetReachabilityFrom(const CNetAddr *paddrPartner = nullptr) const;
 
     explicit CNetAddr(const struct in6_addr &pipv6Addr,
                       const uint32_t scope = 0);
     bool GetIn6Addr(struct in6_addr *pipv6Addr) const;
 
     friend bool operator==(const CNetAddr &a, const CNetAddr &b);
     friend bool operator!=(const CNetAddr &a, const CNetAddr &b) {
         return !(a == b);
     }
     friend bool operator<(const CNetAddr &a, const CNetAddr &b);
 
     ADD_SERIALIZE_METHODS;
 
     template <typename Stream, typename Operation>
     inline void SerializationOp(Stream &s, Operation ser_action) {
         READWRITE(ip);
     }
 
     friend class CSubNet;
 };
 
 class CSubNet {
 protected:
     /// Network (base) address
     CNetAddr network;
     /// Netmask, in network byte order
     uint8_t netmask[16];
     /// Is this value valid? (only used to signal parse errors)
     bool valid;
 
 public:
     CSubNet();
     CSubNet(const CNetAddr &addr, int32_t mask);
     CSubNet(const CNetAddr &addr, const CNetAddr &mask);
 
     // constructor for single ip subnet (<ipv4>/32 or <ipv6>/128)
     explicit CSubNet(const CNetAddr &addr);
 
     bool Match(const CNetAddr &addr) const;
 
     std::string ToString() const;
     bool IsValid() const;
 
     friend bool operator==(const CSubNet &a, const CSubNet &b);
     friend bool operator!=(const CSubNet &a, const CSubNet &b) {
         return !(a == b);
     }
     friend bool operator<(const CSubNet &a, const CSubNet &b);
 
     ADD_SERIALIZE_METHODS;
 
     template <typename Stream, typename Operation>
     inline void SerializationOp(Stream &s, Operation ser_action) {
         READWRITE(network);
         READWRITE(netmask);
         READWRITE(valid);
     }
 };
 
 /** A combination of a network address (CNetAddr) and a (TCP) port */
 class CService : public CNetAddr {
 protected:
     // host order
-    unsigned short port;
+    uint16_t port;
 
 public:
     CService();
     CService(const CNetAddr &ip, unsigned short port);
     CService(const struct in_addr &ipv4Addr, unsigned short port);
     explicit CService(const struct sockaddr_in &addr);
     unsigned short GetPort() const;
     bool GetSockAddr(struct sockaddr *paddr, socklen_t *addrlen) const;
     bool SetSockAddr(const struct sockaddr *paddr);
     friend bool operator==(const CService &a, const CService &b);
     friend bool operator!=(const CService &a, const CService &b) {
         return !(a == b);
     }
     friend bool operator<(const CService &a, const CService &b);
     std::vector<uint8_t> GetKey() const;
     std::string ToString() const;
     std::string ToStringPort() const;
     std::string ToStringIPPort() const;
 
     CService(const struct in6_addr &ipv6Addr, unsigned short port);
     explicit CService(const struct sockaddr_in6 &addr);
 
     ADD_SERIALIZE_METHODS;
 
     template <typename Stream, typename Operation>
     inline void SerializationOp(Stream &s, Operation ser_action) {
         READWRITE(ip);
-        unsigned short portN = htons(port);
-        READWRITE(Span<uint8_t>((uint8_t *)&portN, 2));
-        if (ser_action.ForRead()) {
-            port = ntohs(portN);
-        }
+        READWRITE(WrapBigEndian(port));
     }
 };
 
 #endif // BITCOIN_NETADDRESS_H
diff --git a/src/serialize.h b/src/serialize.h
index b3a08ea4c..abe229396 100644
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -1,998 +1,1044 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_SERIALIZE_H
 #define BITCOIN_SERIALIZE_H
 
 #include <compat/endian.h>
 #include <prevector.h>
 #include <span.h>
 
 #include <algorithm>
 #include <array>
 #include <cassert>
 #include <cstdint>
 #include <cstring>
 #include <ios>
 #include <limits>
 #include <map>
 #include <memory>
 #include <set>
 #include <string>
 #include <utility>
 #include <vector>
 
 static const uint64_t MAX_SIZE = 0x02000000;
 
 /**
  * Dummy data type to identify deserializing constructors.
  *
  * By convention, a constructor of a type T with signature
  *
  *   template <typename Stream> T::T(deserialize_type, Stream& s)
  *
  * is a deserializing constructor, which builds the type by deserializing it
  * from s. If T contains const fields, this is likely the only way to do so.
  */
 struct deserialize_type {};
 constexpr deserialize_type deserialize{};
 
 /**
  * Used to bypass the rule against non-const reference to temporary
  * where it makes sense with wrappers.
  */
 template <typename T> inline T &REF(const T &val) {
     return const_cast<T &>(val);
 }
 
 /**
  * Used to acquire a non-const pointer "this" to generate bodies of const
  * serialization operations from a template
  */
 template <typename T> inline T *NCONST_PTR(const T *val) {
     return const_cast<T *>(val);
 }
 
 //! Safely convert odd char pointer types to standard ones.
 inline char *CharCast(char *c) {
     return c;
 }
 inline char *CharCast(uint8_t *c) {
     return (char *)c;
 }
 inline const char *CharCast(const char *c) {
     return c;
 }
 inline const char *CharCast(const uint8_t *c) {
     return (const char *)c;
 }
 
 /**
  * Lowest-level serialization and conversion.
  * @note Sizes of these types are verified in the tests
  */
 template <typename Stream> inline void ser_writedata8(Stream &s, uint8_t obj) {
     s.write((char *)&obj, 1);
 }
 template <typename Stream>
 inline void ser_writedata16(Stream &s, uint16_t obj) {
     obj = htole16(obj);
     s.write((char *)&obj, 2);
 }
 template <typename Stream>
+inline void ser_writedata16be(Stream &s, uint16_t obj) {
+    obj = htobe16(obj);
+    s.write((char *)&obj, 2);
+}
+template <typename Stream>
 inline void ser_writedata32(Stream &s, uint32_t obj) {
     obj = htole32(obj);
     s.write((char *)&obj, 4);
 }
 template <typename Stream>
 inline void ser_writedata32be(Stream &s, uint32_t obj) {
     obj = htobe32(obj);
     s.write((char *)&obj, 4);
 }
 template <typename Stream>
 inline void ser_writedata64(Stream &s, uint64_t obj) {
     obj = htole64(obj);
     s.write((char *)&obj, 8);
 }
 template <typename Stream> inline uint8_t ser_readdata8(Stream &s) {
     uint8_t obj;
     s.read((char *)&obj, 1);
     return obj;
 }
 template <typename Stream> inline uint16_t ser_readdata16(Stream &s) {
     uint16_t obj;
     s.read((char *)&obj, 2);
     return le16toh(obj);
 }
+template <typename Stream> inline uint16_t ser_readdata16be(Stream &s) {
+    uint16_t obj;
+    s.read((char *)&obj, 2);
+    return be16toh(obj);
+}
 template <typename Stream> inline uint32_t ser_readdata32(Stream &s) {
     uint32_t obj;
     s.read((char *)&obj, 4);
     return le32toh(obj);
 }
 template <typename Stream> inline uint32_t ser_readdata32be(Stream &s) {
     uint32_t obj;
     s.read((char *)&obj, 4);
     return be32toh(obj);
 }
 template <typename Stream> inline uint64_t ser_readdata64(Stream &s) {
     uint64_t obj;
     s.read((char *)&obj, 8);
     return le64toh(obj);
 }
 inline uint64_t ser_double_to_uint64(double x) {
     union {
         double x;
         uint64_t y;
     } tmp;
     tmp.x = x;
     return tmp.y;
 }
 inline uint32_t ser_float_to_uint32(float x) {
     union {
         float x;
         uint32_t y;
     } tmp;
     tmp.x = x;
     return tmp.y;
 }
 inline double ser_uint64_to_double(uint64_t y) {
     union {
         double x;
         uint64_t y;
     } tmp;
     tmp.y = y;
     return tmp.x;
 }
 inline float ser_uint32_to_float(uint32_t y) {
     union {
         float x;
         uint32_t y;
     } tmp;
     tmp.y = y;
     return tmp.x;
 }
 
 /////////////////////////////////////////////////////////////////
 //
 // Templates for serializing to anything that looks like a stream,
 // i.e. anything that supports .read(char*, size_t) and .write(char*, size_t)
 //
 class CSizeComputer;
 
 enum {
     // primary actions
     SER_NETWORK = (1 << 0),
     SER_DISK = (1 << 1),
     SER_GETHASH = (1 << 2),
 };
 
 //! Convert the reference base type to X, without changing constness or
 //! reference type.
 template <typename X> X &ReadWriteAsHelper(X &x) {
     return x;
 }
 template <typename X> const X &ReadWriteAsHelper(const X &x) {
     return x;
 }
 
 #define READWRITE(...) (::SerReadWriteMany(s, ser_action, __VA_ARGS__))
 #define READWRITEAS(type, obj)                                                 \
     (::SerReadWriteMany(s, ser_action, ReadWriteAsHelper<type>(obj)))
 
 /**
  * Implement three methods for serializable objects. These are actually wrappers
  * over "SerializationOp" template, which implements the body of each class'
  * serialization code. Adding "ADD_SERIALIZE_METHODS" in the body of the class
  * causes these wrappers to be added as members.
  */
 #define ADD_SERIALIZE_METHODS                                                  \
     template <typename Stream> void Serialize(Stream &s) const {               \
         NCONST_PTR(this)->SerializationOp(s, CSerActionSerialize());           \
     }                                                                          \
     template <typename Stream> void Unserialize(Stream &s) {                   \
         SerializationOp(s, CSerActionUnserialize());                           \
     }
 
 #ifndef CHAR_EQUALS_INT8
 // TODO Get rid of bare char
 template <typename Stream> inline void Serialize(Stream &s, char a) {
     ser_writedata8(s, a);
 }
 #endif
 template <typename Stream> inline void Serialize(Stream &s, int8_t a) {
     ser_writedata8(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, uint8_t a) {
     ser_writedata8(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, int16_t a) {
     ser_writedata16(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, uint16_t a) {
     ser_writedata16(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, int32_t a) {
     ser_writedata32(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, uint32_t a) {
     ser_writedata32(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, int64_t a) {
     ser_writedata64(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, uint64_t a) {
     ser_writedata64(s, a);
 }
 template <typename Stream> inline void Serialize(Stream &s, float a) {
     ser_writedata32(s, ser_float_to_uint32(a));
 }
 template <typename Stream> inline void Serialize(Stream &s, double a) {
     ser_writedata64(s, ser_double_to_uint64(a));
 }
 template <typename Stream, size_t N>
 inline void Serialize(Stream &s, const int8_t (&a)[N]) {
     s.write(a, N);
 }
 template <typename Stream, size_t N>
 inline void Serialize(Stream &s, const uint8_t (&a)[N]) {
     s.write(CharCast(a), N);
 }
 template <typename Stream, size_t N>
 inline void Serialize(Stream &s, const std::array<int8_t, N> &a) {
     s.write(a.data(), N);
 }
 template <typename Stream, size_t N>
 inline void Serialize(Stream &s, const std::array<uint8_t, N> &a) {
     s.write(CharCast(a.data()), N);
 }
 #ifndef CHAR_EQUALS_INT8
 // TODO Get rid of bare char
 template <typename Stream> inline void Unserialize(Stream &s, char &a) {
     a = ser_readdata8(s);
 }
 template <typename Stream, size_t N>
 inline void Serialize(Stream &s, const char (&a)[N]) {
     s.write(a, N);
 }
 template <typename Stream, size_t N>
 inline void Serialize(Stream &s, const std::array<char, N> &a) {
     s.write(a.data(), N);
 }
 #endif
 template <typename Stream>
 inline void Serialize(Stream &s, const Span<const uint8_t> &span) {
     s.write(CharCast(span.data()), span.size());
 }
 template <typename Stream>
 inline void Serialize(Stream &s, const Span<uint8_t> &span) {
     s.write(CharCast(span.data()), span.size());
 }
 template <typename Stream> inline void Unserialize(Stream &s, int8_t &a) {
     a = ser_readdata8(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, uint8_t &a) {
     a = ser_readdata8(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, int16_t &a) {
     a = ser_readdata16(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, uint16_t &a) {
     a = ser_readdata16(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, int32_t &a) {
     a = ser_readdata32(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, uint32_t &a) {
     a = ser_readdata32(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, int64_t &a) {
     a = ser_readdata64(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, uint64_t &a) {
     a = ser_readdata64(s);
 }
 template <typename Stream> inline void Unserialize(Stream &s, float &a) {
     a = ser_uint32_to_float(ser_readdata32(s));
 }
 template <typename Stream> inline void Unserialize(Stream &s, double &a) {
     a = ser_uint64_to_double(ser_readdata64(s));
 }
 template <typename Stream, size_t N>
 inline void Unserialize(Stream &s, int8_t (&a)[N]) {
     s.read(a, N);
 }
 template <typename Stream, size_t N>
 inline void Unserialize(Stream &s, uint8_t (&a)[N]) {
     s.read(CharCast(a), N);
 }
 template <typename Stream, size_t N>
 inline void Unserialize(Stream &s, std::array<int8_t, N> &a) {
     s.read(a.data(), N);
 }
 template <typename Stream, size_t N>
 inline void Unserialize(Stream &s, std::array<uint8_t, N> &a) {
     s.read(CharCast(a.data()), N);
 }
 #ifndef CHAR_EQUALS_INT8
 template <typename Stream, size_t N>
 inline void Unserialize(Stream &s, char (&a)[N]) {
     s.read(CharCast(a), N);
 }
 template <typename Stream, size_t N>
 inline void Unserialize(Stream &s, std::array<char, N> &a) {
     s.read(CharCast(a.data()), N);
 }
 #endif
 
 template <typename Stream> inline void Serialize(Stream &s, bool a) {
     char f = a;
     ser_writedata8(s, f);
 }
 template <typename Stream> inline void Unserialize(Stream &s, bool &a) {
     char f = ser_readdata8(s);
     a = f;
 }
 template <typename Stream>
 inline void Unserialize(Stream &s, Span<uint8_t> &span) {
     s.read(CharCast(span.data()), span.size());
 }
 
 /**
  * Compact Size
  * size <  253        -- 1 byte
  * size <= USHRT_MAX  -- 3 bytes  (253 + 2 bytes)
  * size <= UINT_MAX   -- 5 bytes  (254 + 4 bytes)
  * size >  UINT_MAX   -- 9 bytes  (255 + 8 bytes)
  */
 inline uint32_t GetSizeOfCompactSize(uint64_t nSize) {
     if (nSize < 253) {
         return sizeof(uint8_t);
     }
     if (nSize <= std::numeric_limits<uint16_t>::max()) {
         return sizeof(uint8_t) + sizeof(uint16_t);
     }
     if (nSize <= std::numeric_limits<uint32_t>::max()) {
         return sizeof(uint8_t) + sizeof(uint32_t);
     }
 
     return sizeof(uint8_t) + sizeof(uint64_t);
 }
 
 inline void WriteCompactSize(CSizeComputer &os, uint64_t nSize);
 
 template <typename Stream> void WriteCompactSize(Stream &os, uint64_t nSize) {
     if (nSize < 253) {
         ser_writedata8(os, nSize);
     } else if (nSize <= std::numeric_limits<uint16_t>::max()) {
         ser_writedata8(os, 253);
         ser_writedata16(os, nSize);
     } else if (nSize <= std::numeric_limits<uint32_t>::max()) {
         ser_writedata8(os, 254);
         ser_writedata32(os, nSize);
     } else {
         ser_writedata8(os, 255);
         ser_writedata64(os, nSize);
     }
     return;
 }
 
 template <typename Stream> uint64_t ReadCompactSize(Stream &is) {
     uint8_t chSize = ser_readdata8(is);
     uint64_t nSizeRet = 0;
     if (chSize < 253) {
         nSizeRet = chSize;
     } else if (chSize == 253) {
         nSizeRet = ser_readdata16(is);
         if (nSizeRet < 253) {
             throw std::ios_base::failure("non-canonical ReadCompactSize()");
         }
     } else if (chSize == 254) {
         nSizeRet = ser_readdata32(is);
         if (nSizeRet < 0x10000u) {
             throw std::ios_base::failure("non-canonical ReadCompactSize()");
         }
     } else {
         nSizeRet = ser_readdata64(is);
         if (nSizeRet < 0x100000000ULL) {
             throw std::ios_base::failure("non-canonical ReadCompactSize()");
         }
     }
     if (nSizeRet > MAX_SIZE) {
         throw std::ios_base::failure("ReadCompactSize(): size too large");
     }
     return nSizeRet;
 }
 
 /**
  * Variable-length integers: bytes are a MSB base-128 encoding of the number.
  * The high bit in each byte signifies whether another digit follows. To make
  * sure the encoding is one-to-one, one is subtracted from all but the last
  * digit. Thus, the byte sequence a[] with length len, where all but the last
  * byte has bit 128 set, encodes the number:
  *
  *  (a[len-1] & 0x7F) + sum(i=1..len-1, 128^i*((a[len-i-1] & 0x7F)+1))
  *
  * Properties:
  * * Very small (0-127: 1 byte, 128-16511: 2 bytes, 16512-2113663: 3 bytes)
  * * Every integer has exactly one encoding
  * * Encoding does not depend on size of original integer type
  * * No redundancy: every (infinite) byte sequence corresponds to a list
  *   of encoded integers.
  *
  * 0:         [0x00]  256:        [0x81 0x00]
  * 1:         [0x01]  16383:      [0xFE 0x7F]
  * 127:       [0x7F]  16384:      [0xFF 0x00]
  * 128:  [0x80 0x00]  16511:      [0xFF 0x7F]
  * 255:  [0x80 0x7F]  65535: [0x82 0xFE 0x7F]
  * 2^32:           [0x8E 0xFE 0xFE 0xFF 0x00]
  */
 
 /**
  * Mode for encoding VarInts.
  *
  * Currently there is no support for signed encodings. The default mode will not
  * compile with signed values, and the legacy "nonnegative signed" mode will
  * accept signed values, but improperly encode and decode them if they are
  * negative. In the future, the DEFAULT mode could be extended to support
  * negative numbers in a backwards compatible way, and additional modes could be
  * added to support different varint formats (e.g. zigzag encoding).
  */
 enum class VarIntMode { DEFAULT, NONNEGATIVE_SIGNED };
 
 template <VarIntMode Mode, typename I> struct CheckVarIntMode {
     constexpr CheckVarIntMode() {
         static_assert(Mode != VarIntMode::DEFAULT || std::is_unsigned<I>::value,
                       "Unsigned type required with mode DEFAULT.");
         static_assert(Mode != VarIntMode::NONNEGATIVE_SIGNED ||
                           std::is_signed<I>::value,
                       "Signed type required with mode NONNEGATIVE_SIGNED.");
     }
 };
 
 template <VarIntMode Mode, typename I>
 inline unsigned int GetSizeOfVarInt(I n) {
     CheckVarIntMode<Mode, I>();
     int nRet = 0;
     while (true) {
         nRet++;
         if (n <= 0x7F) {
             return nRet;
         }
         n = (n >> 7) - 1;
     }
 }
 
 template <typename I> inline void WriteVarInt(CSizeComputer &os, I n);
 
 template <typename Stream, VarIntMode Mode, typename I>
 void WriteVarInt(Stream &os, I n) {
     CheckVarIntMode<Mode, I>();
     uint8_t tmp[(sizeof(n) * 8 + 6) / 7];
     int len = 0;
     while (true) {
         tmp[len] = (n & 0x7F) | (len ? 0x80 : 0x00);
         if (n <= 0x7F) {
             break;
         }
         n = (n >> 7) - 1;
         len++;
     }
     do {
         ser_writedata8(os, tmp[len]);
     } while (len--);
 }
 
 template <typename Stream, VarIntMode Mode, typename I>
 I ReadVarInt(Stream &is) {
     CheckVarIntMode<Mode, I>();
     I n = 0;
     while (true) {
         uint8_t chData = ser_readdata8(is);
         if (n > (std::numeric_limits<I>::max() >> 7)) {
             throw std::ios_base::failure("ReadVarInt(): size too large");
         }
         n = (n << 7) | (chData & 0x7F);
         if ((chData & 0x80) == 0) {
             return n;
         }
         if (n == std::numeric_limits<I>::max()) {
             throw std::ios_base::failure("ReadVarInt(): size too large");
         }
         n++;
     }
 }
 
 #define VARINT(obj, ...) WrapVarInt<__VA_ARGS__>(REF(obj))
 #define COMPACTSIZE(obj) CCompactSize(REF(obj))
 #define LIMITED_STRING(obj, n) LimitedString<n>(REF(obj))
 
 template <VarIntMode Mode, typename I> class CVarInt {
 protected:
     I &n;
 
 public:
     explicit CVarInt(I &nIn) : n(nIn) {}
 
     template <typename Stream> void Serialize(Stream &s) const {
         WriteVarInt<Stream, Mode, I>(s, n);
     }
 
     template <typename Stream> void Unserialize(Stream &s) {
         n = ReadVarInt<Stream, Mode, I>(s);
     }
 };
 
+/** Serialization wrapper class for big-endian integers.
+ *
+ * Use this wrapper around integer types that are stored in memory in native
+ * byte order, but serialized in big endian notation. This is only intended
+ * to implement serializers that are compatible with existing formats, and
+ * its use is not recommended for new data structures.
+ *
+ * Only 16-bit types are supported for now.
+ */
+template <typename I> class BigEndian {
+protected:
+    I &m_val;
+
+public:
+    explicit BigEndian(I &val) : m_val(val) {
+        static_assert(std::is_unsigned<I>::value,
+                      "BigEndian type must be unsigned integer");
+        static_assert(sizeof(I) == 2 && std::numeric_limits<I>::min() == 0 &&
+                          std::numeric_limits<I>::max() ==
+                              std::numeric_limits<uint16_t>::max(),
+                      "Unsupported BigEndian size");
+    }
+
+    template <typename Stream> void Serialize(Stream &s) const {
+        ser_writedata16be(s, m_val);
+    }
+
+    template <typename Stream> void Unserialize(Stream &s) {
+        m_val = ser_readdata16be(s);
+    }
+};
+
 class CCompactSize {
 protected:
     uint64_t &n;
 
 public:
     explicit CCompactSize(uint64_t &nIn) : n(nIn) {}
 
     template <typename Stream> void Serialize(Stream &s) const {
         WriteCompactSize<Stream>(s, n);
     }
 
     template <typename Stream> void Unserialize(Stream &s) {
         n = ReadCompactSize<Stream>(s);
     }
 };
 
 template <size_t Limit> class LimitedString {
 protected:
     std::string &string;
 
 public:
     explicit LimitedString(std::string &_string) : string(_string) {}
 
     template <typename Stream> void Unserialize(Stream &s) {
         size_t size = ReadCompactSize(s);
         if (size > Limit) {
             throw std::ios_base::failure("String length limit exceeded");
         }
         string.resize(size);
         if (size != 0) {
             s.read((char *)string.data(), size);
         }
     }
 
     template <typename Stream> void Serialize(Stream &s) const {
         WriteCompactSize(s, string.size());
         if (!string.empty()) {
             s.write((char *)string.data(), string.size());
         }
     }
 };
 
 template <VarIntMode Mode = VarIntMode::DEFAULT, typename I>
 CVarInt<Mode, I> WrapVarInt(I &n) {
     return CVarInt<Mode, I>{n};
 }
 
+template <typename I> BigEndian<I> WrapBigEndian(I &n) {
+    return BigEndian<I>(n);
+}
+
 /**
  * Forward declarations
  */
 
 /**
  * string
  */
 template <typename Stream, typename C>
 void Serialize(Stream &os, const std::basic_string<C> &str);
 template <typename Stream, typename C>
 void Unserialize(Stream &is, std::basic_string<C> &str);
 
 /**
  * prevector
  * prevectors of uint8_t are a special case and are intended to be serialized as
  * a single opaque blob.
  */
 template <typename Stream, unsigned int N, typename T>
 void Serialize_impl(Stream &os, const prevector<N, T> &v, const uint8_t &);
 template <typename Stream, unsigned int N, typename T, typename V>
 void Serialize_impl(Stream &os, const prevector<N, T> &v, const V &);
 template <typename Stream, unsigned int N, typename T>
 inline void Serialize(Stream &os, const prevector<N, T> &v);
 template <typename Stream, unsigned int N, typename T>
 void Unserialize_impl(Stream &is, prevector<N, T> &v, const uint8_t &);
 template <typename Stream, unsigned int N, typename T, typename V>
 void Unserialize_impl(Stream &is, prevector<N, T> &v, const V &);
 template <typename Stream, unsigned int N, typename T>
 inline void Unserialize(Stream &is, prevector<N, T> &v);
 
 /**
  * vector
  * vectors of uint8_t are a special case and are intended to be serialized as a
  * single opaque blob.
  */
 template <typename Stream, typename T, typename A>
 void Serialize_impl(Stream &os, const std::vector<T, A> &v, const uint8_t &);
 template <typename Stream, typename T, typename A, typename V>
 void Serialize_impl(Stream &os, const std::vector<T, A> &v, const V &);
 template <typename Stream, typename T, typename A>
 inline void Serialize(Stream &os, const std::vector<T, A> &v);
 template <typename Stream, typename T, typename A>
 void Unserialize_impl(Stream &is, std::vector<T, A> &v, const uint8_t &);
 template <typename Stream, typename T, typename A, typename V>
 void Unserialize_impl(Stream &is, std::vector<T, A> &v, const V &);
 template <typename Stream, typename T, typename A>
 inline void Unserialize(Stream &is, std::vector<T, A> &v);
 
 /**
  * pair
  */
 template <typename Stream, typename K, typename T>
 void Serialize(Stream &os, const std::pair<K, T> &item);
 template <typename Stream, typename K, typename T>
 void Unserialize(Stream &is, std::pair<K, T> &item);
 
 /**
  * map
  */
 template <typename Stream, typename K, typename T, typename Pred, typename A>
 void Serialize(Stream &os, const std::map<K, T, Pred, A> &m);
 template <typename Stream, typename K, typename T, typename Pred, typename A>
 void Unserialize(Stream &is, std::map<K, T, Pred, A> &m);
 
 /**
  * set
  */
 template <typename Stream, typename K, typename Pred, typename A>
 void Serialize(Stream &os, const std::set<K, Pred, A> &m);
 template <typename Stream, typename K, typename Pred, typename A>
 void Unserialize(Stream &is, std::set<K, Pred, A> &m);
 
 /**
  * shared_ptr
  */
 template <typename Stream, typename T>
 void Serialize(Stream &os, const std::shared_ptr<const T> &p);
 template <typename Stream, typename T>
 void Unserialize(Stream &os, std::shared_ptr<const T> &p);
 
 /**
  * unique_ptr
  */
 template <typename Stream, typename T>
 void Serialize(Stream &os, const std::unique_ptr<const T> &p);
 template <typename Stream, typename T>
 void Unserialize(Stream &os, std::unique_ptr<const T> &p);
 
 /**
  * If none of the specialized versions above matched, default to calling member
  * function.
  */
 template <typename Stream, typename T>
 inline void Serialize(Stream &os, const T &a) {
     a.Serialize(os);
 }
 
 template <typename Stream, typename T>
 inline void Unserialize(Stream &is, T &&a) {
     a.Unserialize(is);
 }
 
 /**
  * string
  */
 template <typename Stream, typename C>
 void Serialize(Stream &os, const std::basic_string<C> &str) {
     WriteCompactSize(os, str.size());
     if (!str.empty()) {
         os.write((char *)str.data(), str.size() * sizeof(C));
     }
 }
 
 template <typename Stream, typename C>
 void Unserialize(Stream &is, std::basic_string<C> &str) {
     size_t nSize = ReadCompactSize(is);
     str.resize(nSize);
     if (nSize != 0) {
         is.read((char *)str.data(), nSize * sizeof(C));
     }
 }
 
 /**
  * prevector
  */
 template <typename Stream, unsigned int N, typename T>
 void Serialize_impl(Stream &os, const prevector<N, T> &v, const uint8_t &) {
     WriteCompactSize(os, v.size());
     if (!v.empty()) {
         os.write((char *)v.data(), v.size() * sizeof(T));
     }
 }
 
 template <typename Stream, unsigned int N, typename T, typename V>
 void Serialize_impl(Stream &os, const prevector<N, T> &v, const V &) {
     WriteCompactSize(os, v.size());
     for (const T &i : v) {
         ::Serialize(os, i);
     }
 }
 
 template <typename Stream, unsigned int N, typename T>
 inline void Serialize(Stream &os, const prevector<N, T> &v) {
     Serialize_impl(os, v, T());
 }
 
 template <typename Stream, unsigned int N, typename T>
 void Unserialize_impl(Stream &is, prevector<N, T> &v, const uint8_t &) {
     // Limit size per read so bogus size value won't cause out of memory
     v.clear();
     size_t nSize = ReadCompactSize(is);
     size_t i = 0;
     while (i < nSize) {
         size_t blk = std::min(nSize - i, size_t(1 + 4999999 / sizeof(T)));
         v.resize(i + blk);
         is.read((char *)&v[i], blk * sizeof(T));
         i += blk;
     }
 }
 
 template <typename Stream, unsigned int N, typename T, typename V>
 void Unserialize_impl(Stream &is, prevector<N, T> &v, const V &) {
     v.clear();
     size_t nSize = ReadCompactSize(is);
     size_t i = 0;
     size_t nMid = 0;
     while (nMid < nSize) {
         nMid += 5000000 / sizeof(T);
         if (nMid > nSize) {
             nMid = nSize;
         }
         v.resize(nMid);
         for (; i < nMid; i++) {
             Unserialize(is, v[i]);
         }
     }
 }
 
 template <typename Stream, unsigned int N, typename T>
 inline void Unserialize(Stream &is, prevector<N, T> &v) {
     Unserialize_impl(is, v, T());
 }
 
 /**
  * vector
  */
 template <typename Stream, typename T, typename A>
 void Serialize_impl(Stream &os, const std::vector<T, A> &v, const uint8_t &) {
     WriteCompactSize(os, v.size());
     if (!v.empty()) {
         os.write((char *)v.data(), v.size() * sizeof(T));
     }
 }
 
 template <typename Stream, typename T, typename A, typename V>
 void Serialize_impl(Stream &os, const std::vector<T, A> &v, const V &) {
     WriteCompactSize(os, v.size());
     for (const T &i : v) {
         ::Serialize(os, i);
     }
 }
 
 template <typename Stream, typename T, typename A>
 inline void Serialize(Stream &os, const std::vector<T, A> &v) {
     Serialize_impl(os, v, T());
 }
 
 template <typename Stream, typename T, typename A>
 void Unserialize_impl(Stream &is, std::vector<T, A> &v, const uint8_t &) {
     // Limit size per read so bogus size value won't cause out of memory
     v.clear();
     size_t nSize = ReadCompactSize(is);
     size_t i = 0;
     while (i < nSize) {
         size_t blk = std::min(nSize - i, size_t(1 + 4999999 / sizeof(T)));
         v.resize(i + blk);
         is.read((char *)&v[i], blk * sizeof(T));
         i += blk;
     }
 }
 
 template <typename Stream, typename T, typename A, typename V>
 void Unserialize_impl(Stream &is, std::vector<T, A> &v, const V &) {
     v.clear();
     size_t nSize = ReadCompactSize(is);
     size_t i = 0;
     size_t nMid = 0;
     while (nMid < nSize) {
         nMid += 5000000 / sizeof(T);
         if (nMid > nSize) {
             nMid = nSize;
         }
         v.resize(nMid);
         for (; i < nMid; i++) {
             Unserialize(is, v[i]);
         }
     }
 }
 
 template <typename Stream, typename T, typename A>
 inline void Unserialize(Stream &is, std::vector<T, A> &v) {
     Unserialize_impl(is, v, T());
 }
 
 /**
  * pair
  */
 template <typename Stream, typename K, typename T>
 void Serialize(Stream &os, const std::pair<K, T> &item) {
     Serialize(os, item.first);
     Serialize(os, item.second);
 }
 
 template <typename Stream, typename K, typename T>
 void Unserialize(Stream &is, std::pair<K, T> &item) {
     Unserialize(is, item.first);
     Unserialize(is, item.second);
 }
 
 /**
  * map
  */
 template <typename Stream, typename K, typename T, typename Pred, typename A>
 void Serialize(Stream &os, const std::map<K, T, Pred, A> &m) {
     WriteCompactSize(os, m.size());
     for (const auto &entry : m) {
         Serialize(os, entry);
     }
 }
 
 template <typename Stream, typename K, typename T, typename Pred, typename A>
 void Unserialize(Stream &is, std::map<K, T, Pred, A> &m) {
     m.clear();
     size_t nSize = ReadCompactSize(is);
     typename std::map<K, T, Pred, A>::iterator mi = m.begin();
     for (size_t i = 0; i < nSize; i++) {
         std::pair<K, T> item;
         Unserialize(is, item);
         mi = m.insert(mi, item);
     }
 }
 
 /**
  * set
  */
 template <typename Stream, typename K, typename Pred, typename A>
 void Serialize(Stream &os, const std::set<K, Pred, A> &m) {
     WriteCompactSize(os, m.size());
     for (const K &i : m) {
         Serialize(os, i);
     }
 }
 
 template <typename Stream, typename K, typename Pred, typename A>
 void Unserialize(Stream &is, std::set<K, Pred, A> &m) {
     m.clear();
     size_t nSize = ReadCompactSize(is);
     typename std::set<K, Pred, A>::iterator it = m.begin();
     for (size_t i = 0; i < nSize; i++) {
         K key;
         Unserialize(is, key);
         it = m.insert(it, key);
     }
 }
 
 /**
  * unique_ptr
  */
 template <typename Stream, typename T>
 void Serialize(Stream &os, const std::unique_ptr<const T> &p) {
     Serialize(os, *p);
 }
 
 template <typename Stream, typename T>
 void Unserialize(Stream &is, std::unique_ptr<const T> &p) {
     p.reset(new T(deserialize, is));
 }
 
 /**
  * shared_ptr
  */
 template <typename Stream, typename T>
 void Serialize(Stream &os, const std::shared_ptr<const T> &p) {
     Serialize(os, *p);
 }
 
 template <typename Stream, typename T>
 void Unserialize(Stream &is, std::shared_ptr<const T> &p) {
     p = std::make_shared<const T>(deserialize, is);
 }
 
 /**
  * Support for ADD_SERIALIZE_METHODS and READWRITE macro
  */
 struct CSerActionSerialize {
     constexpr bool ForRead() const { return false; }
 };
 struct CSerActionUnserialize {
     constexpr bool ForRead() const { return true; }
 };
 
 /**
  * ::GetSerializeSize implementations
  *
  * Computing the serialized size of objects is done through a special stream
  * object of type CSizeComputer, which only records the number of bytes written
  * to it.
  *
  * If your Serialize or SerializationOp method has non-trivial overhead for
  * serialization, it may be worthwhile to implement a specialized version for
  * CSizeComputer, which uses the s.seek() method to record bytes that would
  * be written instead.
  */
 class CSizeComputer {
 protected:
     size_t nSize;
 
     const int nVersion;
 
 public:
     explicit CSizeComputer(int nVersionIn) : nSize(0), nVersion(nVersionIn) {}
 
     void write(const char *psz, size_t _nSize) { this->nSize += _nSize; }
 
     /** Pretend _nSize bytes are written, without specifying them. */
     void seek(size_t _nSize) { this->nSize += _nSize; }
 
     template <typename T> CSizeComputer &operator<<(const T &obj) {
         ::Serialize(*this, obj);
         return (*this);
     }
 
     size_t size() const { return nSize; }
 
     int GetVersion() const { return nVersion; }
 };
 
 template <typename Stream> void SerializeMany(Stream &s) {}
 
 template <typename Stream, typename Arg, typename... Args>
 void SerializeMany(Stream &s, const Arg &arg, const Args &... args) {
     ::Serialize(s, arg);
     ::SerializeMany(s, args...);
 }
 
 template <typename Stream> inline void UnserializeMany(Stream &s) {}
 
 template <typename Stream, typename Arg, typename... Args>
 inline void UnserializeMany(Stream &s, Arg &&arg, Args &&... args) {
     ::Unserialize(s, arg);
     ::UnserializeMany(s, args...);
 }
 
 template <typename Stream, typename... Args>
 inline void SerReadWriteMany(Stream &s, CSerActionSerialize ser_action,
                              const Args &... args) {
     ::SerializeMany(s, args...);
 }
 
 template <typename Stream, typename... Args>
 inline void SerReadWriteMany(Stream &s, CSerActionUnserialize ser_action,
                              Args &&... args) {
     ::UnserializeMany(s, args...);
 }
 
 template <typename I> inline void WriteVarInt(CSizeComputer &s, I n) {
     s.seek(GetSizeOfVarInt<I>(n));
 }
 
 inline void WriteCompactSize(CSizeComputer &s, uint64_t nSize) {
     s.seek(GetSizeOfCompactSize(nSize));
 }
 
 template <typename T> size_t GetSerializeSize(const T &t, int nVersion = 0) {
     return (CSizeComputer(nVersion) << t).size();
 }
 
 template <typename... T>
 size_t GetSerializeSizeMany(int nVersion, const T &... t) {
     CSizeComputer sc(nVersion);
     SerializeMany(sc, t...);
     return sc.size();
 }
 
 #endif // BITCOIN_SERIALIZE_H