net.i2p.i2ptunnel

Class BlocklistManager

java.lang.Object

net.i2p.i2ptunnel.BlocklistManager

public class BlocklistManager
extends Object

Manages HTTP blocklists for request filtering.

This class handles two types of blocklists:

• URL Blocklist (http_blocklist.txt) - Contains patterns to match against request URLs. Requests matching these patterns are blocked.
• Client Blocklist (http_blocklist_clients.txt) - Tracks destinations that have been blocked, to prevent repeated abuse.

The blocklist files are located in the I2P config directory and are monitored for changes. The URL blocklist is compiled into a regex pattern for efficient matching.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_CLIENT_LIMIT Default maximum number of entries in the client blocklist
static String	HTTP_BLOCKLIST Default filename for the URL blocklist
static String	HTTP_BLOCKLIST_CLIENTS Default filename for the client blocklist

Constructor Summary

Constructors

Constructor and Description
BlocklistManager(Log log, int clientLimit) Creates a new BlocklistManager.

Method Summary

Modifier and Type	Method and Description
boolean	existsInClientBlocklist(String destination) Checks if a destination exists in the client blocklist.
int	getClientBlocklistSize() Gets the current size of the client blocklist.
String	getMatchedBlocklistString(StringBuilder command) Gets the matched string from the blocklist for a request.
void	logBlockedDestination(String destination) Logs a blocked destination to the client blocklist.
boolean	shouldBlockRequest(StringBuilder command) Checks if a request should be blocked based on the URL blocklist.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_CLIENT_LIMIT

public static final int DEFAULT_CLIENT_LIMIT

Default maximum number of entries in the client blocklist

See Also:

Constant Field Values

HTTP_BLOCKLIST

public static final String HTTP_BLOCKLIST

Default filename for the URL blocklist

See Also:

Constant Field Values

HTTP_BLOCKLIST_CLIENTS

public static final String HTTP_BLOCKLIST_CLIENTS

Default filename for the client blocklist

See Also:

Constant Field Values

Constructor Detail

BlocklistManager

public BlocklistManager(Log log,
                        int clientLimit)

Creates a new BlocklistManager.

Parameters:

log - the Log instance for logging blocklist events

clientLimit - the maximum number of entries to keep in the client blocklist; if 0 or negative, uses DEFAULT_CLIENT_LIMIT

Method Detail

existsInClientBlocklist

public boolean existsInClientBlocklist(String destination)
                                throws IOException

Checks if a destination exists in the client blocklist.

This method checks if the given destination has been previously blocked. The blocklist file is monitored for changes and will be reloaded if modified.

Parameters:

destination - the Base32-encoded destination to check

Returns:

true if the destination is in the blocklist, false otherwise

Throws:

IOException - if an I/O error occurs

getClientBlocklistSize

public int getClientBlocklistSize()

Gets the current size of the client blocklist.

Returns:

the number of entries in the client blocklist, or -1 if not initialized

getMatchedBlocklistString

public String getMatchedBlocklistString(StringBuilder command)

Gets the matched string from the blocklist for a request.

If shouldBlockRequest() returns true, this method can be called to retrieve the specific pattern that matched.

Parameters:

command - the HTTP request command containing the URL

Returns:

the matched blocklist string, or null if no match

logBlockedDestination

public void logBlockedDestination(String destination)
                           throws IOException

Logs a blocked destination to the client blocklist.

This method adds the destination to the http_blocklist_clients.txt file if not already present. The client blocklist is used to track destinations that have been blocked, to prevent repeated abuse attempts.

The client blocklist has a maximum size limit. When the limit is reached, the oldest entry is removed before adding a new one.

Parameters:

destination - the Base32-encoded destination to log

Throws:

IOException - if an I/O error occurs

shouldBlockRequest

public boolean shouldBlockRequest(StringBuilder command)

Checks if a request should be blocked based on the URL blocklist.

This method checks if the request URL matches any pattern in the http_blocklist.txt file. The blocklist file is monitored for changes and will be reloaded if modified.

Each line in the blocklist file is treated as a literal string (not regex), case-insensitive matching is applied.

Parameters:

command - the HTTP request command containing the URL

Returns:

true if the request should be blocked, false otherwise