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The doc formatting changes introduced in the recent go version is increasing the diff for all of the new commits. Formatting it all in this commit will help the readability of future PRs by reducing the diff.
39 lines
1.9 KiB
Go
39 lines
1.9 KiB
Go
// Copyright (c) 2014 The btcsuite developers
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// Use of this source code is governed by an ISC
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// license that can be found in the LICENSE file.
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/*
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Package addrmgr implements concurrency safe Bitcoin address manager.
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# Address Manager Overview
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In order maintain the peer-to-peer Bitcoin network, there needs to be a source
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of addresses to connect to as nodes come and go. The Bitcoin protocol provides
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the getaddr and addr messages to allow peers to communicate known addresses with
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each other. However, there needs to a mechanism to store those results and
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select peers from them. It is also important to note that remote peers can't
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be trusted to send valid peers nor attempt to provide you with only peers they
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control with malicious intent.
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With that in mind, this package provides a concurrency safe address manager for
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caching and selecting peers in a non-deterministic manner. The general idea is
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the caller adds addresses to the address manager and notifies it when addresses
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are connected, known good, and attempted. The caller also requests addresses as
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it needs them.
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The address manager internally segregates the addresses into groups and
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non-deterministically selects groups in a cryptographically random manner. This
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reduce the chances multiple addresses from the same nets are selected which
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generally helps provide greater peer diversity, and perhaps more importantly,
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drastically reduces the chances an attacker is able to coerce your peer into
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only connecting to nodes they control.
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The address manager also understands routability and Tor addresses and tries
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hard to only return routable addresses. In addition, it uses the information
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provided by the caller about connected, known good, and attempted addresses to
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periodically purge peers which no longer appear to be good peers as well as
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bias the selection toward known good peers. The general idea is to make a best
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effort at only providing usable addresses.
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*/
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package addrmgr
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