Do not absolutely protect local peers and make eviction more aggressive.#7082
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gmaxwell wants to merge 3 commits intobitcoin:masterfrom
gmaxwell:evict_more
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Do not absolutely protect local peers and make eviction more aggressive.#7082gmaxwell wants to merge 3 commits intobitcoin:masterfrom gmaxwell:evict_more
gmaxwell wants to merge 3 commits intobitcoin:masterfrom
gmaxwell:evict_more
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Contributor
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concept ACK |
Contributor
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I would split this into two commits:
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Contributor
Author
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@pstratem Okay, I split it up and also added protection for tx relayers. I wanted to get something in that distinguishes good onion peers from bad; ultimately I want to add peer POW to this, but thats a non-trivial amount of work. So right now TXs are at least something. It would be good to add blocks too, though that block addition pipeline makes it a little hard to avoid crediting people from sending duplicate blocks. |
With automatic tor HS support in place we should probably not be providing absolute protection for local peers, since HS inbound could be used to attack pretty easily. Instead, this counts on the latency metric inside AttemptToEvictConnection to privilege actually local peers. This makes sure that in the case of tying group size to select the group with the newest member, since newest time is the final selection criteria.
This makes eviction generally more aggressive by making it willing to evict the last unprotected peer in a netgroup if the new connection comes from a netgroup where we have no unprotected peers.
This protects four peers that most recently sent us a valid transaction to our memory pool. This metric is costly for attackers to control since it requires sending acceptable transactions, and an attacker which is blocking transactions is inherently disadvantaged for this criteria.
Contributor
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Concept ACK Will look at code after rebase. |
Member
Member
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Needs rebase if still relevant. (c.f. #7453) |
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With automatic tor HS support in place we should probably not be providing
absolute protection for local peers, since HS inbound could be used to
attack pretty easily. Instead, this counts on the latency metric inside
AttemptToEvictConnection to privilege actually local peers.
This change also makes eviction generally more aggressive by making it
willing to evict the unprotected peer in a netgroup, if the new
connection comes from a netgroup where we have no unprotected peers.
It also makes sure that in the case of tying group size to select the
group with the newest member, since newest time is the final selection
criteria.
The third commit protects four peers that most recently sent us a valid
transaction to our memory pool. This metric is costly for attackers to
control since it requires sending acceptable transactions, and an
attacker which is blocking transactions is inherently disadvantaged for this
criteria.