CConnman then passes the current best height into CNode at creation time.
This way CConnman/CNode have no dependency on main for height, and the signals
only move in one direction.
This also helps to prevent identity leakage a tiny bit. Before this change, an
attacker could theoretically make 2 connections on different interfaces. They
would connect fully on one, and only establish the initial connection on the
other. Once they receive a new block, they would relay it to your first
connection, and immediately commence the version handshake on the second. Since
the new block height is reflected immediately, they could attempt to learn
whether the two connections were correlated.
This is, of course, incredibly unlikely to work due to the small timings
involved and receipt from other senders. But it doesn't hurt to lock-in
nBestHeight at the time of connection, rather than letting the remote choose
the time.
This behavior seems to have been quite racy and broken.
Move nLocalHostNonce into CNode, and check received nonces against all
non-fully-connected nodes. If there's a match, assume we've connected
to ourself.
35fe039 Rename to PrecomputedTransactionData (Pieter Wuille)
ab48c5e Unit test for sighash caching (Nicolas DORIER)
d2c5d04 Precompute sighashes (Pieter Wuille)
We should learn about new peers via address messages.
An inbound peer connecting to us tells us nothing about
its ability to accept incoming connections from us, so
we shouldn't assume that we can connect to it based on
this.
The vast majority of nodes on the network do not accept
incoming connections, adding them will only slow down
the process of making a successful connection in the
future.
Nodes which have configured themselves to not announce would prefer we
not violate their privacy by announcing them in GETADDR responses.
Tests if addresses are online or offline by briefly connecting to them. These short lived connections are referred to as feeler connections. Feeler connections are designed to increase the number of fresh online addresses in tried by selecting and connecting to addresses in new. One feeler connection is attempted on average once every two minutes.
This change was suggested as Countermeasure 4 in
Eclipse Attacks on Bitcoin’s Peer-to-Peer Network, Ethan Heilman,
Alison Kendler, Aviv Zohar, Sharon Goldberg. ePrint Archive Report
2015/263. March 2015.
9d4eb9a Do diskspace check before import thread is started (Pieter Wuille)
aa59f2e Add extra message to avoid a long 'Loading banlist' (Pieter Wuille)
0fd2a33 Use a signal to continue init after genesis activation (Pieter Wuille)
a5072a7 util: Remove zero-argument versions of LogPrint and error (Wladimir J. van der Laan)
695041e util: Update tinyformat (Wladimir J. van der Laan)
c59c434 qa: Add test for standardness of segwit v0 outputs (Suhas Daftuar)
1ffaff2 Make witness v0 outputs non-standard before segwit activation (Johnson Lau)