NTCPTransport (I2P Anonymous Network - Java Documentation

java.lang.Object
- net.i2p.router.transport.TransportImpl
- - net.i2p.router.transport.ntcp.NTCPTransport

All Implemented Interfaces:

Transport
```
public class NTCPTransport
extends TransportImpl
```
The NIO TCP transport

Nested Class Summary
- Nested classes/interfaces inherited from interface net.i2p.router.transport.Transport
  Transport.AddressSource

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`ESTABLISH_TIMEOUT` how long from initial connection attempt (accept() or connect()) until the con must be established to avoid premature close()ing
`static String`	`MIN_SIGTYPE_VERSION` RI sigtypes supported in 0.9.16
`(package private) static int`	`NTCP2_INT_VERSION`
`(package private) static String`	`NTCP2_VERSION` "2"
`(package private) static String`	`NTCP2_VERSION_ALT` "2,"
`static String`	`PROP_BIND_INTERFACE` this is rarely if ever used, default is to bind to wildcard address
`static String`	`PROP_I2NP_NTCP_AUTO_IP`
`static String`	`PROP_I2NP_NTCP_AUTO_PORT`
`static String`	`PROP_I2NP_NTCP_HOSTNAME`
`static String`	`PROP_I2NP_NTCP_PORT`
`static String`	`PROP_NTCP2_IV` b64 static IV
`static String`	`PROP_NTCP2_SP` b64 static private key
`static String`	`STYLE`
`static String`	`STYLE2`

Fields inherited from class net.i2p.router.transport.TransportImpl
_context, _currentAddresses, ADJUST_COST, CONGESTION_COST_ADJUSTMENT, PROP_IPV6_FIREWALLED

Constructor Summary

Constructors
Constructor and Description

NTCPTransport(RouterContext ctx, DHSessionKeyBuilder.Factory dh, X25519KeyFactory xdh)

Constructors
Constructor and Description
`NTCPTransport(RouterContext ctx, DHSessionKeyBuilder.Factory dh, X25519KeyFactory xdh)`

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`void`	`afterSend(OutNetMessage msg, boolean sendSuccessful, boolean allowRequeue, long msToSend)` The transport is done sending this message.
`boolean`	`allowConnection()`
`TransportBid`	`bid(RouterInfo toAddress, int dataSize)`
`int`	`countActivePeers()` How many peers have we talked to in the last 5 minutes? As of 0.9.20, actually returns active peer count, not total.
`int`	`countActiveSendPeers()` How many peers are we actively sending messages to (this minute)
`int`	`countPeers()` How many peers are we connected to?
`(package private) void`	`establishing(NTCPConnection con)` add us to the establishment timeout process
`(package private) void`	`expireTimedOut()` called in the EventPumper no more than once a second or so, closing any unconnected/unestablished connections
`void`	`externalAddressReceived(Transport.AddressSource source, byte[] ip, int port)` UDP changed addresses, tell NTCP and (possibly) restart
`void`	`externalAddressRemoved(Transport.AddressSource source, boolean ipv6)` Notify a transport of an external address change.
`void`	`forceDisconnect(net.i2p.data.Hash peer)` Tell the transport to disconnect from this peer.
`void`	`forwardPortStatus(byte[] ip, int port, int externalPort, boolean success, String reason)` If we didn't used to be forwarded, and we have an address, and we are configured to use UPnP, update our RouterAddress Don't do anything now.
`String`	`getAltStyle()` An alternate supported style, or null.
`List<Long>`	`getClockSkews()` Return our peer clock skews on this transport.
`(package private) DHSessionKeyBuilder`	`getDHBuilder()`
`Set<net.i2p.data.Hash>`	`getEstablished()` Connected peers.
`(package private) byte[]`	`getNTCP2StaticIV()` The static IV
`(package private) byte[]`	`getNTCP2StaticPrivkey()` The static priv key
`(package private) byte[]`	`getNTCP2StaticPubkey()` The static priv key
`Collection<NTCPConnection>`	`getPeers()` For /peers UI only.
`(package private) EventPumper`	`getPumper()` Hook for NTCPConnection
`CommSystemFacade.Status`	`getReachabilityStatus()` Maybe we should trust UPnP here and report OK if it opened the port, but for now we don't.
`(package private) Reader`	`getReader()` Hook for NTCPConnection
`int`	`getRequestedPort()` What INTERNAL port would the transport like to have forwarded by UPnP.
`String`	`getStyle()` The unique identity of this Transport
`(package private) Writer`	`getWriter()` Hook for NTCPConnection
`(package private) X25519KeyFactory`	`getXDHFactory()`
`(package private) NTCPConnection`	`inboundEstablished(NTCPConnection con)`
`boolean`	`isAlive()`
`boolean`	`isBacklogged(net.i2p.data.Hash dest)`
`boolean`	`isEstablished(net.i2p.data.Hash dest)`
`(package private) boolean`	`isHXHIValid(byte[] hxhi)` Incoming connection replay detection.
`(package private) boolean`	`isNTCP1Enabled()` Is NTCP1 enabled?
`(package private) boolean`	`isNTCP2Enabled()` Is NTCP2 enabled?
`void`	`mayDisconnect(net.i2p.data.Hash peer)` Tell the transport that we may disconnect from this peer.
`protected void`	`outboundMessageReady()` This message is called whenever a new message is added to the send pool, and it should not block Only used by NTCP.
`(package private) NTCPConnection`	`removeCon(NTCPConnection con)`
`void`	`renderStatusHTML(Writer out, int sortFlags)`
`void`	`renderStatusHTML(Writer out, String urlBase, int sortFlags)` Deprecated. as of 0.9.31
`(package private) void`	`returnUnused(DHSessionKeyBuilder builder)` Return an unused DH key builder to be put back onto the queue for reuse.
`(package private) void`	`sendComplete(OutNetMessage msg)` queue up afterSend call, which can take some time w/ jobs, etc
`(package private) void`	`setLastBadSkew(long skew)` A positive number means our clock is ahead of theirs.
`void`	`startListening()` Called by TransportManager.
`void`	`stopListening()` This doesn't (completely) block, caller should check isAlive() before calling startListening() or restartListening()

Methods inherited from class net.i2p.router.transport.TransportImpl
_t, _t, afterSend, afterSend, afterSend, allowLocal, getCurrentAddress, getCurrentAddresses, getIP, getIPv6Config, getMaxConnections, getMostRecentErrorMessages, getNextMessage, getSavedLocalAddresses, getTargetAddresses, hasCurrentAddress, haveCapacity, haveCapacity, isIPv4Firewalled, isIPv6Firewalled, isPubliclyRoutable, isUnreachable, markReachable, markUnreachable, messageReceived, ngettext, recheckReachability, removeAddress, removeAddress, renderStatusHTML, replaceAddress, saveLocalAddress, send, setIP, setListener, updateAddress, wasUnreachable

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - PROP_I2NP_NTCP_HOSTNAME
```
public static final String PROP_I2NP_NTCP_HOSTNAME
```
    See Also:
    
    Constant Field Values
  - PROP_I2NP_NTCP_PORT
```
public static final String PROP_I2NP_NTCP_PORT
```
    See Also:
    
    Constant Field Values
  - PROP_I2NP_NTCP_AUTO_PORT
```
public static final String PROP_I2NP_NTCP_AUTO_PORT
```
    See Also:
    
    Constant Field Values
  - PROP_I2NP_NTCP_AUTO_IP
```
public static final String PROP_I2NP_NTCP_AUTO_IP
```
    See Also:
    
    Constant Field Values
  - PROP_BIND_INTERFACE
```
public static final String PROP_BIND_INTERFACE
```
    this is rarely if ever used, default is to bind to wildcard address
    
    See Also:
    
    Constant Field Values
  - MIN_SIGTYPE_VERSION
```
public static final String MIN_SIGTYPE_VERSION
```
    RI sigtypes supported in 0.9.16
    
    See Also:
    
    Constant Field Values
  - STYLE
```
public static final String STYLE
```
    See Also:
    
    Constant Field Values
  - STYLE2
```
public static final String STYLE2
```
    See Also:
    
    Constant Field Values
  - NTCP2_INT_VERSION
```
static final int NTCP2_INT_VERSION
```
    See Also:
    
    Constant Field Values
  - NTCP2_VERSION
```
static final String NTCP2_VERSION
```
    "2"
  - NTCP2_VERSION_ALT
```
static final String NTCP2_VERSION_ALT
```
    "2,"
  - PROP_NTCP2_SP
```
public static final String PROP_NTCP2_SP
```
    b64 static private key
    
    See Also:
    
    Constant Field Values
  - PROP_NTCP2_IV
```
public static final String PROP_NTCP2_IV
```
    b64 static IV
    
    See Also:
    
    Constant Field Values
  - ESTABLISH_TIMEOUT
```
public static final int ESTABLISH_TIMEOUT
```
    how long from initial connection attempt (accept() or connect()) until the con must be established to avoid premature close()ing
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - NTCPTransport
```
public NTCPTransport(RouterContext ctx,
                     DHSessionKeyBuilder.Factory dh,
                     X25519KeyFactory xdh)
```
    Parameters:
    
    dh - null to disable NTCP1
    
    xdh - null to disable NTCP2
- Method Detail
  - inboundEstablished
```
NTCPConnection inboundEstablished(NTCPConnection con)
```
    Parameters:
    
    con - that is established
    
    Returns:
    
    the previous connection to the same peer, must be closed by caller, null if no such.
  - outboundMessageReady
```
protected void outboundMessageReady()
```
    Description copied from class: TransportImpl
    
    This message is called whenever a new message is added to the send pool, and it should not block Only used by NTCP. SSU throws UOE.
    
    Specified by:
    
    outboundMessageReady in class TransportImpl
  - afterSend
```
public void afterSend(OutNetMessage msg,
                      boolean sendSuccessful,
                      boolean allowRequeue,
                      long msToSend)
```
    Description copied from class: TransportImpl
    
    The transport is done sending this message. This is the method that actually does all of the cleanup - firing off jobs, requeueing, updating stats, etc.
    
    Overrides:
    
    afterSend in class TransportImpl
    
    Parameters:
    
    msg - message in question
    
    sendSuccessful - true if the peer received it
    
    allowRequeue - true if we should try other transports if available
    
    msToSend - how long it took to transfer the data to the peer
  - bid
```
public TransportBid bid(RouterInfo toAddress,
                        int dataSize)
```
    dataSize - assumes full 16-byte header, transports should adjust as necessary
    
    Returns:
    
    a bid or null if unwilling to send
  - allowConnection
```
public boolean allowConnection()
```
  - sendComplete
```
void sendComplete(OutNetMessage msg)
```
    queue up afterSend call, which can take some time w/ jobs, etc
  - isEstablished
```
public boolean isEstablished(net.i2p.data.Hash dest)
```
    Specified by:
    
    isEstablished in interface Transport
    
    Overrides:
    
    isEstablished in class TransportImpl
  - isBacklogged
```
public boolean isBacklogged(net.i2p.data.Hash dest)
```
    Specified by:
    
    isBacklogged in interface Transport
    
    Overrides:
    
    isBacklogged in class TransportImpl
  - mayDisconnect
```
public void mayDisconnect(net.i2p.data.Hash peer)
```
    Tell the transport that we may disconnect from this peer. This is advisory only.
    
    Specified by:
    
    mayDisconnect in interface Transport
    
    Overrides:
    
    mayDisconnect in class TransportImpl
    
    Since:
    
    0.9.24
  - forceDisconnect
```
public void forceDisconnect(net.i2p.data.Hash peer)
```
    Tell the transport to disconnect from this peer.
    
    Since:
    
    0.9.38
  - removeCon
```
NTCPConnection removeCon(NTCPConnection con)
```
    Returns:
    
    usually the con passed in, but possibly a second connection with the same peer... only con or null as of 0.9.37
  - countPeers
```
public int countPeers()
```
    Description copied from class: TransportImpl
    
    How many peers are we connected to?
    
    Specified by:
    
    countPeers in interface Transport
    
    Specified by:
    
    countPeers in class TransportImpl
  - getPeers
```
public Collection<NTCPConnection> getPeers()
```
    For /peers UI only. Not a public API, not for external use.
    
    Returns:
    
    not a copy, do not modify
    
    Since:
    
    0.9.31
  - getEstablished
```
public Set<net.i2p.data.Hash> getEstablished()
```
    Connected peers.
    
    Returns:
    
    a copy, modifiable
    
    Since:
    
    0.9.34
  - countActivePeers
```
public int countActivePeers()
```
    How many peers have we talked to in the last 5 minutes? As of 0.9.20, actually returns active peer count, not total.
    
    Specified by:
    
    countActivePeers in interface Transport
    
    Specified by:
    
    countActivePeers in class TransportImpl
  - countActiveSendPeers
```
public int countActiveSendPeers()
```
    How many peers are we actively sending messages to (this minute)
    
    Specified by:
    
    countActiveSendPeers in interface Transport
    
    Specified by:
    
    countActiveSendPeers in class TransportImpl
  - setLastBadSkew
```
void setLastBadSkew(long skew)
```
    A positive number means our clock is ahead of theirs.
    
    Parameters:
    
    skew - in seconds
  - getClockSkews
```
public List<Long> getClockSkews()
```
    Return our peer clock skews on this transport. List composed of Long, each element representing a peer skew in seconds. A positive number means our clock is ahead of theirs.
    
    Specified by:
    
    getClockSkews in interface Transport
    
    Overrides:
    
    getClockSkews in class TransportImpl
  - isHXHIValid
```
boolean isHXHIValid(byte[] hxhi)
```
    Incoming connection replay detection. As there is no timestamp in the first message, we can't detect something long-delayed. To be fixed in next version of NTCP.
    
    Parameters:
    
    hxhi - using first 8 bytes only
    
    Returns:
    
    valid
    
    Since:
    
    0.9.12
  - startListening
```
public void startListening()
```
    Called by TransportManager. Caller should stop the transport first, then verify stopped with isAlive() Unfortunately TransportManager doesn't do that, so we check here to prevent two pumpers.
  - isAlive
```
public boolean isAlive()
```
  - getReader
```
Reader getReader()
```
    Hook for NTCPConnection
  - getWriter
```
Writer getWriter()
```
    Hook for NTCPConnection
  - getStyle
```
public String getStyle()
```
    Description copied from interface: Transport
    
    The unique identity of this Transport
    
    Returns:
    
    always "NTCP" even if NTCP1 is disabled
  - getAltStyle
```
public String getAltStyle()
```
    An alternate supported style, or null.
    
    Overrides:
    
    getAltStyle in class TransportImpl
    
    Returns:
    
    "NTCP2" or null
    
    Since:
    
    0.9.35
  - getPumper
```
EventPumper getPumper()
```
    Hook for NTCPConnection
  - getDHBuilder
```
DHSessionKeyBuilder getDHBuilder()
```
    Returns:
    
    null if not configured for NTCP1
    
    Since:
    
    0.9
  - getXDHFactory
```
X25519KeyFactory getXDHFactory()
```
    Returns:
    
    null if not configured for NTCP2
    
    Since:
    
    0.9.36
  - returnUnused
```
void returnUnused(DHSessionKeyBuilder builder)
```
    Return an unused DH key builder to be put back onto the queue for reuse.
    
    Parameters:
    
    builder - must not have a peerPublicValue set
    
    Since:
    
    0.9.16
  - establishing
```
void establishing(NTCPConnection con)
```
    add us to the establishment timeout process
  - expireTimedOut
```
void expireTimedOut()
```
    called in the EventPumper no more than once a second or so, closing any unconnected/unestablished connections
  - isNTCP1Enabled
```
boolean isNTCP1Enabled()
```
    Is NTCP1 enabled?
    
    Since:
    
    0.9.39
  - isNTCP2Enabled
```
boolean isNTCP2Enabled()
```
    Is NTCP2 enabled?
    
    Since:
    
    0.9.35
  - getNTCP2StaticPubkey
```
byte[] getNTCP2StaticPubkey()
```
    The static priv key
    
    Since:
    
    0.9.36
  - getNTCP2StaticPrivkey
```
byte[] getNTCP2StaticPrivkey()
```
    The static priv key
    
    Since:
    
    0.9.35
  - getNTCP2StaticIV
```
byte[] getNTCP2StaticIV()
```
    The static IV
    
    Since:
    
    0.9.36
  - externalAddressReceived
```
public void externalAddressReceived(Transport.AddressSource source,
                                    byte[] ip,
                                    int port)
```
    UDP changed addresses, tell NTCP and (possibly) restart
    
    Specified by:
    
    externalAddressReceived in interface Transport
    
    Specified by:
    
    externalAddressReceived in class TransportImpl
    
    Parameters:
    
    ip - typ. IPv4 or IPv6 non-local; may be null to indicate IPv4 failure or port info only
    
    source - defined in Transport.java
    
    port - 0 for unknown or unchanged
    
    Since:
    
    IPv6 moved from CSFI.notifyReplaceAddress()
  - externalAddressRemoved
```
public void externalAddressRemoved(Transport.AddressSource source,
                                   boolean ipv6)
```
    Notify a transport of an external address change. This may be from a local interface, UPnP, a config change, etc. This should not be called if the ip didn't change (from that source's point of view), or is a local address. May be called multiple times for IPv4 or IPv6. The transport should also do its own checking on whether to accept notifications from this source. This can be called after the transport is running. TODO externalAddressRemoved(source, ip, port)
    
    Specified by:
    
    externalAddressRemoved in interface Transport
    
    Overrides:
    
    externalAddressRemoved in class TransportImpl
    
    Parameters:
    
    source - defined in Transport.java
    
    Since:
    
    0.9.20
  - forwardPortStatus
```
public void forwardPortStatus(byte[] ip,
                              int port,
                              int externalPort,
                              boolean success,
                              String reason)
```
    If we didn't used to be forwarded, and we have an address, and we are configured to use UPnP, update our RouterAddress Don't do anything now. If it fails, we don't know if it's because there is no firewall, or if the firewall rejected the request. So we just use the SSU reachability status to decide whether to enable inbound NTCP. SSU will have CSFI build a new NTCP address when it transitions to OK.
    
    Specified by:
    
    forwardPortStatus in interface Transport
    
    Overrides:
    
    forwardPortStatus in class TransportImpl
    
    Parameters:
    
    ip - may be null
    
    port - the internal port
    
    externalPort - the external port, which for now should always be the same as the internal port if the forwarding was successful.
  - getRequestedPort
```
public int getRequestedPort()
```
    Description copied from class: TransportImpl
    
    What INTERNAL port would the transport like to have forwarded by UPnP. This can't be passed via getCurrentAddress(), as we have to open the port before we can publish the address, and that's the external port anyway.
    
    Specified by:
    
    getRequestedPort in interface Transport
    
    Overrides:
    
    getRequestedPort in class TransportImpl
    
    Returns:
    
    current IPv4 port, else NTCP configured port, else -1 (but not UDP port if auto)
  - getReachabilityStatus
```
public CommSystemFacade.Status getReachabilityStatus()
```
    Maybe we should trust UPnP here and report OK if it opened the port, but for now we don't. Just go through and if we have one inbound connection, we must be good. As we drop idle connections pretty quickly, this will be fairly accurate. We have to be careful here because much of the router console code assumes that the reachability status is really just the UDP status. This only returns OK, DISABLED, or UNKNOWN for IPv4 and IPv6. We leave the FIREWALLED status for UDP. Previously returned short, now enum as of 0.9.20
    
    Specified by:
    
    getReachabilityStatus in interface Transport
    
    Specified by:
    
    getReachabilityStatus in class TransportImpl
  - stopListening
```
public void stopListening()
```
    This doesn't (completely) block, caller should check isAlive() before calling startListening() or restartListening()
  - renderStatusHTML
```
public void renderStatusHTML(Writer out,
                             int sortFlags)
                      throws IOException
```
    Throws:
    
    IOException
  - renderStatusHTML
```
@Deprecated
public void renderStatusHTML(Writer out,
                                         String urlBase,
                                         int sortFlags)
                                  throws IOException
```
    Deprecated. as of 0.9.31
    
    Does nothing
    
    Specified by:
    
    renderStatusHTML in interface Transport
    
    Overrides:
    
    renderStatusHTML in class TransportImpl
    
    Throws:
    
    IOException

Class NTCPTransport

Nested Class Summary

Nested classes/interfaces inherited from interface net.i2p.router.transport.Transport

Field Summary

Fields inherited from class net.i2p.router.transport.TransportImpl

Constructor Summary

Method Summary

Methods inherited from class net.i2p.router.transport.TransportImpl

Methods inherited from class java.lang.Object

Field Detail

PROP_I2NP_NTCP_HOSTNAME

PROP_I2NP_NTCP_PORT

PROP_I2NP_NTCP_AUTO_PORT

PROP_I2NP_NTCP_AUTO_IP

PROP_BIND_INTERFACE

MIN_SIGTYPE_VERSION

STYLE

STYLE2

NTCP2_INT_VERSION

NTCP2_VERSION

NTCP2_VERSION_ALT

PROP_NTCP2_SP

PROP_NTCP2_IV

ESTABLISH_TIMEOUT

Constructor Detail

NTCPTransport

Method Detail

inboundEstablished

outboundMessageReady

afterSend

bid

allowConnection

sendComplete

isEstablished

isBacklogged

mayDisconnect

forceDisconnect

removeCon

countPeers

getPeers

getEstablished

countActivePeers

countActiveSendPeers

setLastBadSkew

getClockSkews

isHXHIValid

startListening

isAlive

getReader

getWriter

getStyle

getAltStyle

getPumper

getDHBuilder

getXDHFactory

returnUnused

establishing

expireTimedOut

isNTCP1Enabled

isNTCP2Enabled

getNTCP2StaticPubkey

getNTCP2StaticPrivkey

getNTCP2StaticIV

externalAddressReceived

externalAddressRemoved

forwardPortStatus

getRequestedPort

getReachabilityStatus

stopListening

renderStatusHTML

renderStatusHTML