i2p: initial support

14 files changed, 450 insertions, 40 deletions

diff --git a/ANONYMITY_NETWORKS.md b/ANONYMITY_NETWORKS.md
index 6ac8cd999..a5f18010e 100644
--- a/ANONYMITY_NETWORKS.md
+++ b/ANONYMITY_NETWORKS.md
@@ -1,7 +1,6 @@
 # Anonymity Networks with Monero
 
-Currently only Tor has been integrated into Monero. Providing support for
-Kovri/I2P should be minimal, but has not yet been attempted. The usage of
+Currently only Tor and I2P have been integrated into Monero. The usage of
 these networks is still considered experimental - there are a few pessimistic
 cases where privacy is leaked. The design is intended to maximize privacy of
 the source of a transaction by broadcasting it over an anonymity network, while
@@ -23,8 +22,8 @@ connections enabled.
 
 ## P2P Commands
 
-Only handshakes, peer timed syncs, and transaction broadcast messages are
-supported over anonymity networks. If one `--add-exclusive-node` onion address
+Only handshakes, peer timed syncs and transaction broadcast messages are
+supported over anonymity networks. If one `--add-exclusive-node` p2p address
 is specified, then no syncing will take place and only transaction broadcasting
 can occur. It is therefore recommended that `--add-exclusive-node` be combined
 with additional exclusive IPv4 address(es).
@@ -47,9 +46,9 @@ separate process. On most systems the configuration will look like:
 
 which tells `monerod` that ".onion" p2p addresses can be forwarded to a socks
 proxy at IP 127.0.0.1 port 9050 with a max of 10 outgoing connections and
-".i2p" p2p addresses can be forwarded to a socks proxy at IP 127.0.0.1 port 9000
-with the default max outgoing connections. Since there are no seed nodes for
-anonymity connections, peers must be manually specified:
+".b32.i2p" p2p addresses can be forwarded to a socks proxy at IP 127.0.0.1 port
+9000 with the default max outgoing connections. Since there are no seed nodes
+for anonymity connections, peers must be manually specified:
 
 > `--add-exclusive-node rveahdfho7wo4b2m.onion:28083`
 > `--add-peer rveahdfho7wo4b2m.onion:28083`
@@ -64,27 +63,28 @@ Receiving anonymity connections is done through the option
 `--anonymous-inbound`. This option tells `monerod` the inbound address, network
 type, and max connections:
 
-> `--anonymous-inbound rveahdfho7wo4b2m.onion:28083,127.0.0.28083,25`
-> `--anonymous-inbound foobar.i2p:5000,127.0.0.1:30000`
+> `--anonymous-inbound rveahdfho7wo4b2m.onion:28083,127.0.0.1:28083,25`
+> `--anonymous-inbound cmeua5767mz2q5jsaelk2rxhf67agrwuetaso5dzbenyzwlbkg2q.b32.i2p:5000,127.0.0.1:30000`
 
 which tells `monerod` that a max of 25 inbound Tor connections are being
 received at address "rveahdfho7wo4b2m.onion:28083" and forwarded to `monerod`
 localhost port 28083, and a default max I2P connections are being received at
-address "foobar.i2p:5000" and forwarded to `monerod` localhost port 30000.
+address "cmeua5767mz2q5jsaelk2rxhf67agrwuetaso5dzbenyzwlbkg2q.b32.i2p:5000" and
+forwarded to `monerod` localhost port 30000.
 These addresses will be shared with outgoing peers, over the same network type,
 otherwise the peer will not be notified of the peer address by the proxy.
 
 ### Network Types
 
-#### Tor
+#### Tor & I2P
 
-Options `--add-exclusive-node` and `--add-peer` recognize ".onion" addresses,
-and will properly forward those addresses to the proxy provided with
-`--proxy tor,...`.
+Options `--add-exclusive-node` and `--add-peer` recognize ".onion" and
+".b32.i2p" addresses, and will properly forward those addresses to the proxy
+provided with `--proxy tor,...` or `--proxy i2p,...`.
 
-Option `--anonymous-inbound` also recognizes ".onion" addresses, and will
-automatically be sent out to outgoing Tor connections so the peer can
-distribute the address to its other peers.
+Option `--anonymous-inbound` also recognizes ".onion" and ".b32.i2p" addresses,
+and will automatically be sent out to outgoing Tor/I2P connections so the peer
+can distribute the address to its other peers.
 
 ##### Configuration
 
@@ -99,11 +99,8 @@ This will store key information in `/var/lib/tor/data/monero` and will forward
 `/usr/lib/tor/data/monero/hostname` will contain the ".onion" address for use
 with `--anonymous-inbound`.
 
-#### Kovri/I2P
-
-Support for this network has not been implemented. Using ".i2p" addresses or
-specifying "i2p" will currently generate an error.
-
+I2P must be configured with a standard server tunnel. Configuration differs by
+I2P implementation.
 
 ## Privacy Limitations
 
@@ -132,11 +129,11 @@ more difficult.
 ### Bandwidth Usage
 
 An ISP can passively monitor `monerod` connections from a node and observe when
-a transaction is sent over a Tor/Kovri connection via timing analysis + size of
-data sent during that timeframe. Kovri should provide better protection against
+a transaction is sent over a Tor/I2P connection via timing analysis + size of
+data sent during that timeframe. I2P should provide better protection against
 this attack - its connections are not circuit based. However, if a node is
-only using Kovri for broadcasting Monero transactions, the total aggregate of
-Kovri/I2P data would also leak information.
+only using I2P for broadcasting Monero transactions, the total aggregate of
+I2P data would also leak information.
 
 #### Mitigation
 
@@ -165,15 +162,15 @@ simply a best effort attempt.
 ### Active Bandwidth Shaping
 
 An attacker could attempt to bandwidth shape traffic in an attempt to determine
-the source of a Tor/Kovri/I2P connection. There isn't great mitigation against
-this, but Kovri/I2P should provide better protection against this attack since
+the source of a Tor/I2P connection. There isn't great mitigation against
+this, but I2P should provide better protection against this attack since
 the connections are not circuit based.
 
 #### Mitigation
 
-The best mitigiation is to use Kovri/I2P instead of Tor. However, Kovri/I2P
+The best mitigiation is to use I2P instead of Tor. However, I2P
 has a smaller set of users (less cover traffic) and academic reviews, so there
 is a tradeoff in potential isses. Also, anyone attempting this strategy really
 wants to uncover a user, it seems unlikely that this would be performed against
-every Tor/Kovri/I2P user.
+every Tor/I2P user.
 
diff --git a/contrib/epee/include/net/net_utils_base.h b/contrib/epee/include/net/net_utils_base.h
index 82f8a7fe8..ffd106e10 100644
--- a/contrib/epee/include/net/net_utils_base.h
+++ b/contrib/epee/include/net/net_utils_base.h
@@ -47,6 +47,7 @@
 namespace net
 {
 	class tor_address;
+	class i2p_address;
 }
 
 namespace epee
@@ -196,7 +197,7 @@ namespace net_utils
 		template<typename Type> const Type &as() const { return as_mutable<const Type>(); }
 
 		BEGIN_KV_SERIALIZE_MAP()
-			// need to `#include "net/tor_address.h"` when serializing `network_address`
+			// need to `#include "net/[i2p|tor]_address.h"` when serializing `network_address`
 			static constexpr std::integral_constant<bool, is_store> is_store_{};
 
 			std::uint8_t type = std::uint8_t(is_store ? this_ref.get_type_id() : address_type::invalid);
@@ -209,6 +210,8 @@ namespace net_utils
 					return this_ref.template serialize_addr<ipv4_network_address>(is_store_, stg, hparent_section);
 				case address_type::tor:
 					return this_ref.template serialize_addr<net::tor_address>(is_store_, stg, hparent_section);
+				case address_type::i2p:
+					return this_ref.template serialize_addr<net::i2p_address>(is_store_, stg, hparent_section);
 				case address_type::invalid:
 				default:
 					break;
diff --git a/src/cryptonote_config.h b/src/cryptonote_config.h
index 93db71705..716825a2d 100644
--- a/src/cryptonote_config.h
+++ b/src/cryptonote_config.h
@@ -108,7 +108,7 @@
 #define P2P_DEFAULT_PACKET_MAX_SIZE                     50000000     //50000000 bytes maximum packet size
 #define P2P_DEFAULT_PEERS_IN_HANDSHAKE                  250
 #define P2P_DEFAULT_CONNECTION_TIMEOUT                  5000       //5 seconds
-#define P2P_DEFAULT_TOR_CONNECT_TIMEOUT                 20         // seconds
+#define P2P_DEFAULT_SOCKS_CONNECT_TIMEOUT               45         // seconds
 #define P2P_DEFAULT_PING_CONNECTION_TIMEOUT             2000       //2 seconds
 #define P2P_DEFAULT_INVOKE_TIMEOUT                      60*2*1000  //2 minutes
 #define P2P_DEFAULT_HANDSHAKE_INVOKE_TIMEOUT            5000       //5 seconds
diff --git a/src/net/CMakeLists.txt b/src/net/CMakeLists.txt
index a81372125..fdb988f39 100644
--- a/src/net/CMakeLists.txt
+++ b/src/net/CMakeLists.txt
@@ -26,8 +26,8 @@
 # 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.
 
-set(net_sources error.cpp parse.cpp socks.cpp tor_address.cpp)
-set(net_headers error.h parse.h socks.h tor_address.h)
+set(net_sources error.cpp parse.cpp socks.cpp tor_address.cpp i2p_address.cpp)
+set(net_headers error.h parse.h socks.h tor_address.h i2p_address.h)
 
 monero_add_library(net ${net_sources} ${net_headers})
 target_link_libraries(net epee ${Boost_ASIO_LIBRARY})
diff --git a/src/net/fwd.h b/src/net/fwd.h
index ee7c539b0..7cae88251 100644
--- a/src/net/fwd.h
+++ b/src/net/fwd.h
@@ -34,6 +34,7 @@ namespace net
 {
     enum class error : int;
     class tor_address;
+    class i2p_address;
 
     namespace socks
     {
diff --git a/src/net/i2p_address.cpp b/src/net/i2p_address.cpp
new file mode 100644
index 000000000..cba829d3f
--- /dev/null
+++ b/src/net/i2p_address.cpp
@@ -0,0 +1,200 @@
+// Copyright (c) 2019, The Monero 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:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. 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.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// 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 HOLDER 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.
+
+#include "i2p_address.h"
+
+#include <algorithm>
+#include <boost/spirit/include/karma_generate.hpp>
+#include <boost/spirit/include/karma_uint.hpp>
+#include <cassert>
+#include <cstring>
+#include <limits>
+
+#include "net/error.h"
+#include "serialization/keyvalue_serialization.h"
+#include "storages/portable_storage.h"
+#include "string_tools.h"
+
+namespace net
+{
+    namespace
+    {
+        // !TODO only b32 addresses right now
+        constexpr const char tld[] = u8".b32.i2p";
+        constexpr const char unknown_host[] = "<unknown i2p host>";
+
+        constexpr const unsigned b32_length = 52;
+
+        constexpr const char base32_alphabet[] =
+            u8"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz234567";
+
+        expect<void> host_check(boost::string_ref host) noexcept
+        {
+            if (!host.ends_with(tld))
+                return {net::error::expected_tld};
+
+            host.remove_suffix(sizeof(tld) - 1);
+
+            if (host.size() != b32_length)
+                return {net::error::invalid_i2p_address};
+            if (host.find_first_not_of(base32_alphabet) != boost::string_ref::npos)
+                return {net::error::invalid_i2p_address};
+
+            return success();
+        }
+
+        struct i2p_serialized
+        {
+            std::string host;
+            std::uint16_t port;
+
+            BEGIN_KV_SERIALIZE_MAP()
+                KV_SERIALIZE(host)
+                KV_SERIALIZE(port)
+            END_KV_SERIALIZE_MAP()
+        };
+    }
+
+    i2p_address::i2p_address(const boost::string_ref host, const std::uint16_t port) noexcept
+      : port_(port)
+    {
+        // this is a private constructor, throw if moved to public
+        assert(host.size() < sizeof(host_));
+
+        const std::size_t length = std::min(sizeof(host_) - 1, host.size());
+        std::memcpy(host_, host.data(), length);
+        std::memset(host_ + length, 0, sizeof(host_) - length);
+    }
+
+    const char* i2p_address::unknown_str() noexcept
+    {
+        return unknown_host;
+    }
+
+    i2p_address::i2p_address() noexcept
+      : port_(0)
+    {
+        static_assert(sizeof(unknown_host) <= sizeof(host_), "bad buffer size");
+        std::memcpy(host_, unknown_host, sizeof(unknown_host));
+        std::memset(host_ + sizeof(unknown_host), 0, sizeof(host_) - sizeof(unknown_host));
+    }
+
+    expect<i2p_address> i2p_address::make(const boost::string_ref address, const std::uint16_t default_port)
+    {
+        boost::string_ref host = address.substr(0, address.rfind(':'));
+        const boost::string_ref port =
+            address.substr(host.size() + (host.size() == address.size() ? 0 : 1));
+
+        MONERO_CHECK(host_check(host));
+
+        std::uint16_t porti = default_port;
+        if (!port.empty() && !epee::string_tools::get_xtype_from_string(porti, std::string{port}))
+            return {net::error::invalid_port};
+
+        static_assert(b32_length + sizeof(tld) == sizeof(i2p_address::host_), "bad internal host size");
+        return i2p_address{host, porti};
+    }
+
+    bool i2p_address::_load(epee::serialization::portable_storage& src, epee::serialization::section* hparent)
+    {
+        i2p_serialized in{};
+        if (in._load(src, hparent) && in.host.size() < sizeof(host_) && (in.host == unknown_host || !host_check(in.host).has_error()))
+        {
+            std::memcpy(host_, in.host.data(), in.host.size());
+            std::memset(host_ + in.host.size(), 0, sizeof(host_) - in.host.size());
+            port_ = in.port;
+            return true;
+        }
+        static_assert(sizeof(unknown_host) <= sizeof(host_), "bad buffer size");
+        std::memcpy(host_, unknown_host, sizeof(unknown_host)); // include null terminator
+        port_ = 0;
+        return false;
+    }
+
+    bool i2p_address::store(epee::serialization::portable_storage& dest, epee::serialization::section* hparent) const
+    {
+        const i2p_serialized out{std::string{host_}, port_};
+        return out.store(dest, hparent);
+    }
+
+    i2p_address::i2p_address(const i2p_address& rhs) noexcept
+      : port_(rhs.port_)
+    {
+        std::memcpy(host_, rhs.host_, sizeof(host_));
+    }
+
+    i2p_address& i2p_address::operator=(const i2p_address& rhs) noexcept
+    {
+        if (this != std::addressof(rhs))
+        {
+            port_ = rhs.port_;
+            std::memcpy(host_, rhs.host_, sizeof(host_));
+        }
+        return *this;
+    }
+
+    bool i2p_address::is_unknown() const noexcept
+    {
+        static_assert(1 <= sizeof(host_), "host size too small");
+        return host_[0] == '<'; // character is not allowed otherwise
+    }
+
+    bool i2p_address::equal(const i2p_address& rhs) const noexcept
+    {
+        return port_ == rhs.port_ && is_same_host(rhs);
+    }
+
+    bool i2p_address::less(const i2p_address& rhs) const noexcept
+    {
+        return std::strcmp(host_str(), rhs.host_str()) < 0 || port() < rhs.port();
+    }
+
+    bool i2p_address::is_same_host(const i2p_address& rhs) const noexcept
+    {
+        return std::strcmp(host_str(), rhs.host_str()) == 0;
+    }
+
+    std::string i2p_address::str() const
+    {
+        const std::size_t host_length = std::strlen(host_str());
+        const std::size_t port_length =
+            port_ == 0 ? 0 : std::numeric_limits<std::uint16_t>::digits10 + 2;
+
+        std::string out{};
+        out.reserve(host_length + port_length);
+        out.assign(host_str(), host_length);
+
+        if (port_ != 0)
+        {
+            out.push_back(':');
+            namespace karma = boost::spirit::karma;
+            karma::generate(std::back_inserter(out), karma::ushort_, port());
+        }
+        return out;
+    }
+}
diff --git a/src/net/i2p_address.h b/src/net/i2p_address.h
new file mode 100644
index 000000000..28a1118ba
--- /dev/null
+++ b/src/net/i2p_address.h
@@ -0,0 +1,140 @@
+// Copyright (c) 2019, The Monero 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:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. 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.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// 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 HOLDER 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.
+
+#pragma once
+
+#include <boost/utility/string_ref.hpp>
+#include <cstdint>
+#include <string>
+
+#include "common/expect.h"
+#include "net/enums.h"
+#include "net/error.h"
+
+namespace epee
+{
+namespace serialization
+{
+    class portable_storage;
+    struct section;
+}
+}
+
+namespace net
+{
+    //! b32 i2p address; internal format not condensed/decoded.
+    class i2p_address
+    {
+        std::uint16_t port_;
+        char host_[61]; // null-terminated
+
+        //! Keep in private, `host.size()` has no runtime check
+        i2p_address(boost::string_ref host, std::uint16_t port) noexcept;
+
+    public:
+        //! \return Size of internal buffer for host.
+        static constexpr std::size_t buffer_size() noexcept { return sizeof(host_); }
+
+        //! \return `<unknown tor host>`.
+        static const char* unknown_str() noexcept;
+
+        //! An object with `port() == 0` and `host_str() == unknown_str()`.
+        i2p_address() noexcept;
+
+        //! \return A default constructed `i2p_address` object.
+        static i2p_address unknown() noexcept { return i2p_address{}; }
+
+        /*!
+            Parse `address` in b32 i2p format (i.e. x.b32.i2p:80)
+            with `default_port` being used if port is not specified in
+            `address`.
+        */
+        static expect<i2p_address> make(boost::string_ref address, std::uint16_t default_port = 0);
+
+        //! Load from epee p2p format, and \return false if not valid tor address
+        bool _load(epee::serialization::portable_storage& src, epee::serialization::section* hparent);
+
+        //! Store in epee p2p format
+        bool store(epee::serialization::portable_storage& dest, epee::serialization::section* hparent) const;
+
+        // Moves and copies are currently identical
+
+        i2p_address(const i2p_address& rhs) noexcept;
+        ~i2p_address() = default;
+        i2p_address& operator=(const i2p_address& rhs) noexcept;
+
+        //! \return True if default constructed or via `unknown()`.
+        bool is_unknown() const noexcept;
+
+        bool equal(const i2p_address& rhs) const noexcept;
+        bool less(const i2p_address& rhs) const noexcept;
+
+        //! \return True if i2p addresses are identical.
+        bool is_same_host(const i2p_address& rhs) const noexcept;
+
+        //! \return `x.b32.i2p` or `x.b32.i2p:z` if `port() != 0`.
+        std::string str() const;
+
+        //! \return Null-terminated `x.b32.i2p` value or `unknown_str()`.
+        const char* host_str() const noexcept { return host_; }
+
+        //! \return Port value or `0` if unspecified.
+        std::uint16_t port() const noexcept { return port_; }
+
+        static constexpr bool is_loopback() noexcept { return false; }
+        static constexpr bool is_local() noexcept { return false; }
+
+        static constexpr epee::net_utils::address_type get_type_id() noexcept
+        {
+            return epee::net_utils::address_type::i2p;
+        }
+
+        static constexpr epee::net_utils::zone get_zone() noexcept
+        {
+            return epee::net_utils::zone::i2p;
+        }
+
+        //! \return `!is_unknown()`.
+        bool is_blockable() const noexcept { return !is_unknown(); }
+    };
+
+    inline bool operator==(const i2p_address& lhs, const i2p_address& rhs) noexcept
+    {
+        return lhs.equal(rhs);
+    }
+
+    inline bool operator!=(const i2p_address& lhs, const i2p_address& rhs) noexcept
+    {
+        return !lhs.equal(rhs);
+    }
+
+    inline bool operator<(const i2p_address& lhs, const i2p_address& rhs) noexcept
+    {
+        return lhs.less(rhs);
+    }
+} // net
diff --git a/src/net/parse.cpp b/src/net/parse.cpp
index ebf91eeff..eaaadb67e 100644
--- a/src/net/parse.cpp
+++ b/src/net/parse.cpp
@@ -29,6 +29,7 @@
 #include "parse.h"
 
 #include "net/tor_address.h"
+#include "net/i2p_address.h"
 #include "string_tools.h"
 
 namespace net
@@ -43,7 +44,7 @@ namespace net
         if (host.ends_with(".onion"))
             return tor_address::make(address, default_port);
         if (host.ends_with(".i2p"))
-            return make_error_code(net::error::invalid_i2p_address); // not yet implemented (prevent public DNS lookup)
+            return i2p_address::make(address, default_port);
 
         std::uint16_t port = default_port;
         if (host.size() < address.size())
diff --git a/src/net/parse.h b/src/net/parse.h
index 9195ddc2b..5804c4128 100644
--- a/src/net/parse.h
+++ b/src/net/parse.h
@@ -37,11 +37,11 @@
 namespace net
 {
     /*!
-      Identifies onion and IPv4 addresses and returns them as a generic
+      Identifies onion, i2p and IPv4 addresses and returns them as a generic
       `network_address`. If the type is unsupported, it might be a hostname,
       and `error() == net::error::kUnsupportedAddress` is returned.
 
-      \param address An onion address, ipv4 address or hostname. Hostname
+      \param address An onion address, i2p address, ipv4 address or hostname. Hostname
           will return an error.
       \param default_port If `address` does not specify a port, this value
           will be used.
diff --git a/src/net/socks.cpp b/src/net/socks.cpp
index f31efc8c1..53154369b 100644
--- a/src/net/socks.cpp
+++ b/src/net/socks.cpp
@@ -40,6 +40,7 @@
 
 #include "net/net_utils_base.h"
 #include "net/tor_address.h"
+#include "net/i2p_address.h"
 
 namespace net
 {
@@ -273,6 +274,13 @@ namespace socks
         return false;
     }
 
+    bool client::set_connect_command(const net::i2p_address& address)
+    {
+        if (!address.is_unknown())
+            return set_connect_command(address.host_str(), address.port());
+        return false;
+    }
+
     bool client::set_resolve_command(boost::string_ref domain)
     {
         if (socks_version() != version::v4a_tor)
diff --git a/src/net/socks.h b/src/net/socks.h
index d29a51ccb..825937792 100644
--- a/src/net/socks.h
+++ b/src/net/socks.h
@@ -155,6 +155,9 @@ namespace socks
         //! Try to set `address` as remote Tor hidden service connection request.
         bool set_connect_command(const net::tor_address& address);
 
+        //! Try to set `address` as remote i2p hidden service connection request.
+        bool set_connect_command(const net::i2p_address& address);
+
         //! Try to set `domain` as remote DNS A record lookup request.
         bool set_resolve_command(boost::string_ref domain);
 
diff --git a/src/p2p/net_node.cpp b/src/p2p/net_node.cpp
index 8639fdb3b..2f0678913 100644
--- a/src/p2p/net_node.cpp
+++ b/src/p2p/net_node.cpp
@@ -46,13 +46,14 @@
 #include "net/socks.h"
 #include "net/parse.h"
 #include "net/tor_address.h"
+#include "net/i2p_address.h"
 #include "p2p/p2p_protocol_defs.h"
 #include "string_tools.h"
 
 namespace
 {
     constexpr const boost::chrono::milliseconds future_poll_interval{500};
-    constexpr const std::chrono::seconds tor_connect_timeout{P2P_DEFAULT_TOR_CONNECT_TIMEOUT};
+    constexpr const std::chrono::seconds socks_connect_timeout{P2P_DEFAULT_SOCKS_CONNECT_TIMEOUT};
 
     std::int64_t get_max_connections(const boost::iterator_range<boost::string_ref::const_iterator> value) noexcept
     {
@@ -90,6 +91,9 @@ namespace
         case net::tor_address::get_type_id():
             set = client->set_connect_command(remote.as<net::tor_address>());
             break;
+        case net::i2p_address::get_type_id():
+            set = client->set_connect_command(remote.as<net::i2p_address>());
+            break;
         default:
             MERROR("Unsupported network address in socks_connect");
             return false;
@@ -177,6 +181,9 @@ namespace nodetool
             case epee::net_utils::zone::tor:
                 proxies.back().zone = epee::net_utils::zone::tor;
                 break;
+            case epee::net_utils::zone::i2p:
+                proxies.back().zone = epee::net_utils::zone::i2p;
+                break;
             default:
                 MERROR("Invalid network for --" << arg_proxy.name);
                 return boost::none;
@@ -235,6 +242,10 @@ namespace nodetool
                 inbounds.back().our_address = std::move(*our_address);
                 inbounds.back().default_remote = net::tor_address::unknown();
                 break;
+            case net::i2p_address::get_type_id():
+                inbounds.back().our_address = std::move(*our_address);
+                inbounds.back().default_remote = net::i2p_address::unknown();
+                break;
             default:
                 MERROR("Invalid inbound address (" << address << ") for --" << arg_anonymous_inbound.name << ": " << (our_address ? "invalid type" : our_address.error().message()));
                 return boost::none;
@@ -308,7 +319,7 @@ namespace nodetool
         const auto start = std::chrono::steady_clock::now();
         while (socks_result.wait_for(future_poll_interval) == boost::future_status::timeout)
         {
-            if (tor_connect_timeout < std::chrono::steady_clock::now() - start)
+            if (socks_connect_timeout < std::chrono::steady_clock::now() - start)
             {
                 MERROR("Timeout on socks connect (" << proxy << " to " << remote.str() << ")");
                 return boost::none;
diff --git a/src/p2p/net_peerlist_boost_serialization.h b/src/p2p/net_peerlist_boost_serialization.h
index d2e9efa3d..6c891581f 100644
--- a/src/p2p/net_peerlist_boost_serialization.h
+++ b/src/p2p/net_peerlist_boost_serialization.h
@@ -1,4 +1,4 @@
-	// Copyright (c) 2014-2018, The Monero Project
+// Copyright (c) 2014-2018, The Monero Project
 // 
 // All rights reserved.
 // 
@@ -35,6 +35,7 @@
 #include "common/expect.h"
 #include "net/net_utils_base.h"
 #include "net/tor_address.h"
+#include "net/i2p_address.h"
 #include "p2p/p2p_protocol_defs.h"
 
 #ifdef CRYPTONOTE_PRUNING_DEBUG_SPOOF_SEED
@@ -76,6 +77,9 @@ namespace boost
         case net::tor_address::get_type_id():
           do_serialize<net::tor_address>(is_saving, a, na);
           break;
+        case net::i2p_address::get_type_id():
+          do_serialize<net::i2p_address>(is_saving, a, na);
+          break;
         case epee::net_utils::address_type::invalid:
         default:
           throw std::runtime_error("Unsupported network address type");
@@ -107,6 +111,20 @@ namespace boost
     }
 
     template <class Archive, class ver_type>
+    inline void save(Archive& a, const net::i2p_address& na, const ver_type)
+    {
+      const size_t length = std::strlen(na.host_str());
+      if (length > 255)
+        MONERO_THROW(net::error::invalid_i2p_address, "i2p address too long");
+
+      const uint16_t port{na.port()};
+      const uint8_t len = length;
+      a & port;
+      a & len;
+      a.save_binary(na.host_str(), length);
+    }
+
+    template <class Archive, class ver_type>
     inline void load(Archive& a, net::tor_address& na, const ver_type)
     {
       uint16_t port = 0;
@@ -128,12 +146,39 @@ namespace boost
     }
 
     template <class Archive, class ver_type>
+    inline void load(Archive& a, net::i2p_address& na, const ver_type)
+    {
+      uint16_t port = 0;
+      uint8_t length = 0;
+      a & port;
+      a & length;
+
+      if (length > net::i2p_address::buffer_size())
+        MONERO_THROW(net::error::invalid_i2p_address, "i2p address too long");
+
+      char host[net::i2p_address::buffer_size()] = {0};
+      a.load_binary(host, length);
+      host[sizeof(host) - 1] = 0;
+
+      if (std::strcmp(host, net::i2p_address::unknown_str()) == 0)
+        na = net::i2p_address::unknown();
+      else
+        na = MONERO_UNWRAP(net::i2p_address::make(host, port));
+    }
+
+    template <class Archive, class ver_type>
     inline void serialize(Archive &a, net::tor_address& na, const ver_type ver)
     {
       boost::serialization::split_free(a, na, ver);
     }
 
     template <class Archive, class ver_type>
+    inline void serialize(Archive &a, net::i2p_address& na, const ver_type ver)
+    {
+      boost::serialization::split_free(a, na, ver);
+    }
+
+    template <class Archive, class ver_type>
     inline void serialize(Archive &a,  nodetool::peerlist_entry& pl, const ver_type ver)
     {
       a & pl.adr;
diff --git a/src/p2p/p2p_protocol_defs.h b/src/p2p/p2p_protocol_defs.h
index 6e5e45008..e9449b950 100644
--- a/src/p2p/p2p_protocol_defs.h
+++ b/src/p2p/p2p_protocol_defs.h
@@ -35,6 +35,7 @@
 #include "serialization/keyvalue_serialization.h"
 #include "net/net_utils_base.h"
 #include "net/tor_address.h" // needed for serialization
+#include "net/i2p_address.h" // needed for serialization
 #include "misc_language.h"
 #include "string_tools.h"
 #include "time_helper.h"