This change reduces fingerprinting via timestamps in addr messages.
Previously, the last seen time for an address was updated when
certain protocol commands were received. Now, the last seen time
is set when the peer disconnects if the peer had sent a verack
message and was connected for more than 20 minutes.
This mimics Bitcoin Core commit:
9c2737901b5203f267d21d728019d64b46f1d9f3
Also, add additional sanity checking before updating the peer's
timestamp. These include:
- Do not mark a peer as connected if we never received
a version message.
- Disconnect a peer for sending a verack before btcd
sent a version
- Disconnect a peer for sending multiple verack's
In order to avoid prior situations of stalled syncs due to
outdated peer height data, we now update block heights up peers in
real-time as we learn of their announced
blocks.
Updates happen when:
* A peer sends us an orphan block. We update based on
the height embedded in the scriptSig for the coinbase tx
* When a peer sends us an inv for a block we already know
of
* When peers announce new blocks. Subsequent
announcements that lost the announcement race are
recognized and peer heights are updated accordingly
Additionally, the `getpeerinfo` command has been modified
to include both the starting height, and current height of
connected peers.
Docs have been updated with `getpeerinfo` extension.
Currently, the reference client bans peers that send alerts not signed
with its key. We could verify against their key, but since the
reference client developers are currently unwilling to support other
implementations' alert messages, we will not relay theirs.
Only two operations are performed with this data structure: adding to
the back and removing from the front. Because middle inserts and
deletions are never needed, a linked list results in overall worse
performance due to an extra allocation for each element's node, worse
cache locality, and the runtime cost of boxing/unboxing each item
during accesses.
On top of the performance gains, a slice is more type safe as it is a
true generic data structure making it is impossible to insert or
access an element with the wrong type.
As pointed out in #189, according to the Go documentation, a ticker must
be stopped to release associated resources. This commit adds a defer call
to stop two tickers there were previously not being stopped as well as
changes two others that were being stopped over to use defer so it's more
consistent.
The other ticker in ScheduleShutdown is replaced and already calls Stop
before replacing it, so it has not been modified.
Closes#189.
ok @jrick
This commit uses the new MedianTimeSource API in btcchain to create a
median time source which is stored in the server and is fed time samples
from all remote nodes that are connected. It also modifies all call sites
which now require the the time source to pass it in.
This ensures we backoff when reconnecting to peers for which we don't
understand the replies, just like we do for peers we fail to connect to.
Closes#103
The sync.atomic requires alignment of variables used atomically on ARM.
This commit moves the connected and disconnect variables in the peer
struct up so they are aligned.
Fixes#157.
This commit implements reject handling as defined by BIP0061 and bumps the
maximum supported protocol version to 70002 accordingly.
As a part of supporting this a new error type named RuleError has been
introduced which encapsulates and underlying error which could be one of
the existing TxRuleError or btcchain.RuleError types.
This allows a single high level type assertion to be used to determine if
the block or transaction was rejected due to a rule error or due to an
unexpected error. Meanwhile, an appropriate reject error can be created
from the error by pulling the underlying error out and using it.
Also, a check for minimum protocol version of 209 has been added.
Closes#133.
The done and wait channels used to throttle outgoing data are being used
as semaphores. As mentioned in the previous commit, it's more efficient
to use a 0-byte type and allow compiler optimizations for the specific use
case.
This commit implements full support for filtering based on the filterload,
filteradd, filterclear, and merkleblock messages introduced by BIP0037.
This allows btcd to work seamlessly with SPV wallets such as BitcoinJ.
Original code by @dajohi. Cleanup, bug fixes, and polish by @davecgh.
These changes are a joint effort between myself and @dajohi.
- Separate IP address range/network code into its own file
- Group all of the RFC range declarations together
- Introduces a new unexported function to simplify the range declarations
- Add comments for all exported functions
- Use consistent variable casing in refactored code
- Add initial doc.go package overview
- Bump serialize interval to 10 minutes
- Correct GroupKey to perform as intended
- Make AddLocalAddress return error instead of just a debug message
- Add tests for AddLocalAddress
- Add tests for GroupKey
- Add tests for GetBestLocalAddress
- Use time.Time to improve readability
- Make address manager code golint clean
- Misc cleanup
- Add test coverage reporting
This commit does just enough to move the address manager into its own
package. Since it was not originally written as a package, it will
require a bit of refactoring and cleanup to turn it into a robust
package with a friendly API.
This commit corrects an issue where the data requested by getdata was not
being properly throttled which could lead to higher than desired memory
usage on large requests.
This commit, along with recent commits to btcnet and btcwire, expose a new
network that is intended to provide a private network useful for
simulation testing. To that end, it has the special property that it has
no DNS seeds and will actively ignore all addr and getaddr messages. It
will also not try to connect to any nodes other than those specified via
--connect. This allows the network to remain private to the specific
nodes involved in the testing and not simply become another public
testnet.
The network difficulty is also set extremely low like the regression test
network so blocks can be created extremely quickly without requiring a lot
of hashing power.
In practise the races caused by not protecting these quite simply didn't
matter, they couldn't actually cause any damage whatsoever. However, I
am sick of hearing about these essentially false positivies whenever
someone runs the race detector (yes, i know that race detector has no
false positives but this was effectively harmess).
verified to shut the detector up by dhill.
On unknown inventory types, handleGetDataMsg would loop forever.
After fixing that, if a getdata request only had unknown inventory
types, it would block forever.
ok @davecgh
This commit modifies peers to use a max protocol version that is specified
as a constant in the peer code as opposed to the btcwire.ProtocolVersion
constant.
This allows btcwire to be updated to support new protocol versions without
causing peers to claim they support a protocol version which they actually
don't.
