2cb7e99deee1017a6edd94d82de556895138361d test: also reset CConnman::m_private_broadcast in tests (Vasil Dimov)
91b7c874e2b1479ed29f067cd1bef7724aabd951 test: add ConnmanTestMsg convenience method Reset() (Vasil Dimov)
Pull request description:
Member variables of `CConnman::m_private_broadcast` (introduced in
https://github.com/bitcoin/bitcoin/pull/29415) could influence the tests
which creates non-determinism if the same instance of `CConnman` is used
for repeated test iterations.
So, reset the state of `CConnman::m_private_broadcast` from
`ConnmanTestMsg::Reset()`. Currently this affects the fuzz tests
`process_message` and `process_messages`.
Reported in https://github.com/bitcoin/bitcoin/issues/34476#issuecomment-3849088794
ACKs for top commit:
maflcko:
review ACK 2cb7e99deee1017a6edd94d82de556895138361d 🚙
Crypt-iQ:
tACK 2cb7e99deee1017a6edd94d82de556895138361d
frankomosh:
Code Review ACK 2cb7e99deee1017a6edd94d82de556895138361d
brunoerg:
code review ACK 2cb7e99deee1017a6edd94d82de556895138361d
Tree-SHA512: 0f4b114542da8dc611689457ce67034c15cbfe409b006b2db72bc74078ee9513f5ce3d0e6e67d37c127cfa0a5170fe72fe3ea45ce2a61d45a358dd11bd1881f8
Member variables of `CConnman::m_private_broadcast` (introduced in
https://github.com/bitcoin/bitcoin/pull/29415) could influence the tests
which creates non-determinism if the same instance of `CConnman` is used
for repeated test iterations.
So, reset the state of `CConnman::m_private_broadcast` from
`ConnmanTestMsg::Reset()`. Currently this affects the fuzz tests
`process_message` and `process_messages`.
Reported in
https://github.com/bitcoin/bitcoin/issues/34476#issuecomment-3849088794
fabf8d1c5bdb6a944762792cdc762caa6c1a760b fuzz: Restore SendMessages coverage in process_message(s) fuzz targets (MarcoFalke)
fac7fed397f0fa3924600c1806a46d235a62ee5f refactor: Use std::reference_wrapper<AddrMan> in Connman (MarcoFalke)
Pull request description:
*Found and reported by Crypt-iQ (thanks!)*
Currently the process_message(s) fuzz targets do not have any meaningful `SendMessages` code coverage. This is not ideal.
Fix the problem by adding back the coverage, and by hardening the code here, so that the problem hopefully does not happen again in the future.
### Historic context for this regression
The regression was introduced in commit fa11eea4059a608f591db4469c07a341fd33a031, which built a new deterministic peerman object. However, the patch was incomplete, because it was missing one hunk to replace `g_setup->m_node.peerman->SendMessages(&p2p_node);` with `peerman->SendMessages(&p2p_node);`.
This means the stale and empty peerman from the node context and not the freshly created and deterministic peerman was used.
A simple fix would be to just submit the missing patch hunk. However, this still leaves the risk that the issue is re-introduced at any time in the future. So instead, I think the stale and empty peerman should be de-constructed, so that any call to it will lead to a hard sanitizer error and fuzz failure.
Doing that also uncovered another issue: The connman was holding on to a reference to a stale and empty addrman.
So fix all issues by:
* Allowing the addrman reference in connman to be re-seatable
* Clearing all stale objects, before creating new objects, and then using references to the new objects in all code
ACKs for top commit:
Crypt-iQ:
crACK fabf8d1c5bdb6a944762792cdc762caa6c1a760b
frankomosh:
ACK fabf8d1c5bdb6a944762792cdc762caa6c1a760b
marcofleon:
code review ACK fabf8d1c5bdb6a944762792cdc762caa6c1a760b
sedited:
ACK fabf8d1c5bdb6a944762792cdc762caa6c1a760b
Tree-SHA512: 2e478102b3e928dc7505f00c08d4b9e4f8368407b100bc88f3eb3b82aa6fea5a45bae736c211f5af1551ca0de1a5ffd4a5d196d9473d4c3b87cfed57c9a0b69d
The addrman field is already a reference. However, some tests would
benefit from the reference being re-seatable, so that they do not have
to create a full Connman each time.
Implement opening `ConnectionType::PRIVATE_BROADCAST` connections with
the following properties:
* Only to Tor or I2P (or IPv4/IPv6 through the Tor proxy, if provided)
* Open such connections only when requested and don't maintain N opened
connections of this type.
* Since this is substantially different than what
`OpenNetworkConnection()` does, open the private broadcast connections
from a different thread instead of modifying `OpenNetworkConnection()`
to also open those types of connections.
Co-authored-by: Andrew Toth <andrewstoth@gmail.com>
We run InactivityChecks() for each node everytime poll()/select() every
50ms or so. Rather than calculating the current time once for each node,
just calculate it once and reuse it.
CConnman::Stop() resets semOutbound, yet m_reconnections is not
cleared in Stop. Each ReconnectionInfo contains a grant member
that points to the memory that semOutbound pointed to and ~CConnman
will attempt to access the grant field (memory that was already
freed) when destroying m_reconnections. Fix this by calling
m_reconnections.clear() in CConnman::Stop() and add appropriate
annotations.
b63428ac9ce2c903670409b3e47b9f6730917ae8 rpc: refactor: use more (Maybe)Arg<std::string_view> (stickies-v)
037830ca0dbb6ede9f9d72691c756f4bae6c97e2 refactor: increase string_view usage (stickies-v)
b3bf18f0bac0ffe18206ee20642e11264ba0c99d rpc: refactor: use string_view in Arg/MaybeArg (stickies-v)
Pull request description:
The `RPCHelpMan::{Arg,MaybeArg}` helpers avoid copying (potentially) large strings by returning them as `const std::string*` (`MaybeArg`) or `const std::string&` (`Arg`). For `MaybeArg`, this has the not-so-nice effect that users need to deal with raw pointers, potentially also requiring new functions (e.g. [`EnsureUniqueWalletName` ](d127b25199 (diff-d8bfcfbdd5fa7d5c52d38c1fe5eeac9ce5c5a794cdfaf683585140fa70a32374R32))) with raw pointers being implemented.
This PR aims to improve on this by returning a trivially copyable `std::string_view` (`Arg`) or `std::optional<std::string_view>` (`MaybeArg`), modernizing the interface without introducing any additional copying overhead. In doing so, it also generalizes whether we return by value or by pointer/reference using `std::is_trivially_copyable_v` instead of defining the types manually.
In cases where functions currently take a `const std::string&` and it would be too much work / touching consensus logic to update them (`signmessage.cpp`), a `std::string` copy is made (which was already happening anyway).
The last 2 commits increase usage of the `{Arg,MaybeArg}<std::string_view>` helpers, and could be dropped/pruned if anything turns out to be controversial - I just think it's a nice little cleanup.
ACKs for top commit:
maflcko:
re-ACK b63428ac9ce2c903670409b3e47b9f6730917ae8 🎉
achow101:
ACK b63428ac9ce2c903670409b3e47b9f6730917ae8
pablomartin4btc:
re-ACK [b63428a](b63428ac9c)
w0xlt:
reACK b63428ac9c
Tree-SHA512: b4942c353a1658c22a88d8c9b402c288ad35265a3b88aa2072b1f9b6d921cd073194ed4b00b807cb48ca440f47c87ef3d8e0dd1a5d814be58fc7743f26288277
c76de2eea18076f91dd80b52f66ba790f071a2b1 net: support overriding the proxy selection in ConnectNode() (Vasil Dimov)
Pull request description:
Normally `ConnectNode()` would choose whether to use a proxy and which one. Make it possible to override this from the callers and same for `OpenNetworkConnection()` - pass down the proxy to `ConnectNode()`.
Document both functions.
This is useful if we want to open connections to IPv4 or IPv6 peers through the Tor SOCKS5 proxy.
Also have `OpenNetworkConnection()` return whether the connection succeeded or not. This can be used when the caller needs to keep track of how many (successful) connections were opened.
---
This is part of [#29415 Broadcast own transactions only via short-lived Tor or I2P connections](https://github.com/bitcoin/bitcoin/pull/29415). Putting it in its own PR to reduce the size of #29415 and because it does not depend on the other commits from there.
ACKs for top commit:
stratospher:
ACK c76de2e.
optout21:
ACK c76de2eea18076f91dd80b52f66ba790f071a2b1
mzumsande:
Code Review ACK c76de2eea18076f91dd80b52f66ba790f071a2b1
andrewtoth:
ACK c76de2eea18076f91dd80b52f66ba790f071a2b1
Tree-SHA512: 1d266e4280cdb1d0599971fa8b5da58b1b7451635be46abb15c0b823a1e18cf6e7bcba4a365ad198e6fd1afee4097d81a54253fa680c8b386ca6b9d68d795ff0
0f7d4ee4e8281ed141a6ebb7e0edee7b864e4dcf p2p: Use different inbound inv timer per network (Martin Zumsande)
94db966a3bb52a3677eb5f762447202ed3889f0f net: use generic network key for addrcache (Martin Zumsande)
Pull request description:
Currently, `NextInvToInbounds` schedules each round of `inv` at the same time for all inbound peers. It's being done this way because with a separate timer per peer (like it's done for outbounds), an attacker could do multiple connections to learn about the time a transaction arrived. (#13298).
However, having a single timer for inbounds of all networks is also an obvious fingerprinting vector: Connecting to a suspected pair of privacy-network and clearnet addresses and observing the `inv` pattern makes it trivial to confirm or refute that they are the same node.
This PR changes it such that a separate timer is used for each network.
It uses the existing method from `getaddr` caching and generalizes it to be saved in a new field `m_network_key` in `CNode` which will be used for both `getaddr` caching and `inv` scheduling, and can also be used for any future anti-fingerprinting measures.
ACKs for top commit:
sipa:
utACK 0f7d4ee4e8281ed141a6ebb7e0edee7b864e4dcf
stratospher:
reACK 0f7d4ee.
naiyoma:
Tested ACK 0f7d4ee4e8281ed141a6ebb7e0edee7b864e4dcf
danielabrozzoni:
reACK 0f7d4ee4e8
Tree-SHA512: e197c3005b2522051db432948874320b74c23e01e66988ee1ee11917dac0923f58c1252fa47da24e68b08d7a355d8e5e0a3ccdfa6e4324cb901f21dfa880cd9c
Update select functions that take a const std::string& to take a
std::string_view instead. In a next commit, this allows us to use
the {Arg,MaybeArg}<std::string_view> helper.
Modernizes interface by not forcing users to deal with raw pointers,
without adding copying overhead. Generalizes the logic of whether
we return by value or by optional/pointer.
In cases where functions take a `const std::string&` and it would
be too much work to update them, a string copy is made (which was
already happening anyway).
Normally `ConnectNode()` would choose whether to use a proxy and which
one. Make it possible to override this from the callers and same for
`OpenNetworkConnection()` - pass down the proxy to `ConnectNode()`.
Document both functions.
This is useful if we want to open connections to IPv4 or IPv6 peers
through the Tor SOCKS5 proxy.
Also have `OpenNetworkConnection()` return whether the connection
succeeded or not. This can be used when the caller needs to keep track
of how many (successful) connections were opened.
87e7f37918d42c28033e9f684db52f94eeed617b doc: clarify peer address in getpeerinfo and addnode RPC help (Vasil Dimov)
2a4450ccbbe30f6522c3108f136b2b867b2a87fe net: change FindNode() to not return a node and rename it (Vasil Dimov)
4268abae1a1d06f2c4bd26b85b3a491719217fae net: avoid recursive m_nodes_mutex lock in DisconnectNode() (Vasil Dimov)
3a4d1a25cf949eb5f27d6dfd4e1b4a966b2cde75 net: merge AlreadyConnectedToAddress() and FindNode(CNetAddr) (Vasil Dimov)
Pull request description:
`CConnman::FindNode()` would lock `m_nodes_mutex`, find the node in `m_nodes`, release the mutex and return the node. The current code is safe but it is a dangerous interface where a caller may end up using the node returned from `FindNode()` without owning `m_nodes_mutex` and without having that node's reference count incremented.
Change `FindNode()` to return a boolean since all but one of its callers used its return value to check whether a node exists and did not do anything else with the return value.
Remove a recursive lock on `m_nodes_mutex`.
Rename `FindNode()` to better describe what it does.
ACKs for top commit:
achow101:
ACK 87e7f37918d42c28033e9f684db52f94eeed617b
furszy:
Code review ACK 87e7f37918d42c28033e9f684db52f94eeed617b
hodlinator:
re-ACK 87e7f37918d42c28033e9f684db52f94eeed617b
Tree-SHA512: 44fb64cd1226eca124ed1f447b4a1ebc42cc5c9e8561fc91949bbeaeaa7fa16fcfd664e85ce142e5abe62cb64197c178ca4ca93b3b3217b913e3c498d0b7d1c9
All callers of `CConnman::FindNode()` use its return value `CNode*` only
as a boolean null/notnull. So change that method to return `bool`.
This removes the dangerous pattern of handling a `CNode` object (the
return value of `FindNode()`) without holding `CConnman::m_nodes_mutex`
and without having that object's reference count incremented for the
duration of the usage.
Also rename the method to better describe what it does.
0802398e749c5e16fa7085cd87c91a31bbe043bd fuzz: make it possible to mock (fuzz) CThreadInterrupt (Vasil Dimov)
6d9e5d130d2e1d052044e9a72d44cfffb5d3c771 fuzz: add CConnman::SocketHandler() to the tests (Vasil Dimov)
3265df63a48db187e0d240ce801ee573787fed80 fuzz: add CConnman::InitBinds() to the tests (Vasil Dimov)
91cbf4dbd864b65ba6b107957f087d1d305914b2 fuzz: add CConnman::CreateNodeFromAcceptedSocket() to the tests (Vasil Dimov)
50da7432ec1e5431b243aa30f8a9339f8e8ed97d fuzz: add CConnman::OpenNetworkConnection() to the tests (Vasil Dimov)
e6a917c8f8e0f1a0fa71dc9bbb6e1074f81edea3 fuzz: add Fuzzed NetEventsInterface and use it in connman tests (Vasil Dimov)
e883b37768812d96feec207a37202c7d1b603c1f fuzz: set the output argument of FuzzedSock::Accept() (Vasil Dimov)
Pull request description:
Extend `CConnman` fuzz tests to also exercise the methods `OpenNetworkConnection()`, `CreateNodeFromAcceptedSocket()`, `InitBinds()` and `SocketHandler()`.
Previously fuzzing those methods would have resulted in real socket functions being called in the operating system which is undesirable during fuzzing. Now that https://github.com/bitcoin/bitcoin/pull/21878 is complete all those are mocked to a fuzzed socket and a fuzzed DNS resolver (see how `CreateSock` and `g_dns_lookup` are replaced in the first commit).
ACKs for top commit:
achow101:
ACK 0802398e749c5e16fa7085cd87c91a31bbe043bd
jonatack:
Review re-ACK 0802398e749c5e16fa7085cd87c91a31bbe043bd
dergoegge:
Code review ACK 0802398e749c5e16fa7085cd87c91a31bbe043bd
Tree-SHA512: a717d4e79f42bacf2b029c821fdc265e10e4e5c41af77cd4cb452cc5720ec83c62789d5b3dfafd39a22cc8c0500b18169aa7864d497dded729a32ab863dd6c4d
`CConnman::AlreadyConnectedToAddress()` is the only caller of
`CConnman::FindNode(CNetAddr)`, so merge the two in one function.
The unit test that checked whether `AlreadyConnectedToAddress()` ignores
the port is now unnecessary because now the function takes a `CNetAddr`
argument. It has no access to the port.
The generic key can also be used in other places
where behavior between different network identities should
be uncorrelated to avoid fingerprinting.
This also changes RANDOMIZER_ID - since it is not
being persisted to disk, there are no compatibility issues.
Tor inbound connections do not reveal the peer's actual network address.
Therefore do not apply whitelist permissions to them.
Co-authored-by: Vasil Dimov <vd@FreeBSD.org>
Currently this code is not called in unit tests. Calling should make it
possible to write tests for things like IPC exceptions being thrown during
shutdown.
Better reflect in the documentation that the two methods should be
used in different contexts.
Also update the outdated "call the function without a parameter" phrasing
in the cached version. This wording was accurate when the cache was
introduced in #18991, but became outdated after later commits
(f26502e9fc8a669b30717525597e3f468eaecf79,
81b00f87800f40cb14f2131ff27668bd2bb9e551) added parameters to each
function, and the previous commit changed the function naming completely.
Co-Authored-By: stickies-v <stickies-v@protonmail.com>
Rename GetAddresses to GetAddressesUnsafe to make it clearer that this
function should only be used in trusted contexts. This helps avoid
accidental privacy leaks by preventing the uncached version from being
used in non-trusted scenarios, like P2P.
* Make the methods of `CThreadInterrupt` virtual and store a pointer to
it in `CConnman`, thus making it possible to override with a mocked
instance.
* Initialize `CConnman::m_interrupt_net` from the constructor, making it
possible for callers to supply mocked version.
* Introduce `FuzzedThreadInterrupt` and `ConsumeThreadInterrupt()` and
use them in `src/test/fuzz/connman.cpp` and `src/test/fuzz/i2p.cpp`.
This improves the CPU utilization of the `connman` fuzz test.
As a nice side effect, the `std::shared_ptr` used for
`CConnman::m_interrupt_net` resolves the possible lifetime issues with
it (see the removed comment for that variable).
Historically, the headers have been bumped some time after a file has
been touched. Do it now to avoid having to touch them again in the
future for that reason.
-BEGIN VERIFY SCRIPT-
sed -i --regexp-extended 's;( 20[0-2][0-9])(-20[0-2][0-9])? The Bitcoin Core developers;\1-present The Bitcoin Core developers;g' $( git show --pretty="" --name-only HEAD~1 )
-END VERIFY SCRIPT-
* `CConnman::CalculateKeyedNetGroup()` needs `CNetAddr`, not `CAddress`,
thus change its argument.
* Both callers of `CConnman::CreateNodeFromAcceptedSocket()` create a
dummy `CAddress` from `CService`, so use `CService` instead.
* `GetBindAddress()` only needs to return `CService`.
* `CNode::addrBind` only needs to be `CService`.
9c5775c331e02dab06c78ecbb58488542d16dda7 addrman: cap the `max_pct` to not exceed the maximum number of addresses (brunoerg)
Pull request description:
Fixes#31234
This PR fixes a bad alloc issue in `GetAddresses` by capping the value `max_pct`. In practice, values greater than 100 should be treated as 100 since it's the percentage of addresses to return. Also, it limites the value `max_pct` in connman target to exercise values between 0 and 100.
ACKs for top commit:
adamandrews1:
Code Review ACK 9c5775c331
marcofleon:
Tested ACK 9c5775c331e02dab06c78ecbb58488542d16dda7. Reproduced the crash on master and checked that this fixed it. The checks added to `GetAddr_` look reasonable.
mzumsande:
Code Review ACK 9c5775c331e02dab06c78ecbb58488542d16dda7
vasild:
ACK 9c5775c331e02dab06c78ecbb58488542d16dda7
Tree-SHA512: 2957ae561ccc37df71f43c1863216d2e563522ea70b9a4baee6990e0b4a1ddadccabdcb9115c131a9a57480367b5ebdd03e0e3d4c8583792e2b7d1911a0a06d3
Add a method CNetMessage::GetMemoryUsage and use this for accounting of
the size of the process receive queue instead of the raw message size.
This ensures that allocation and deserialization overhead is taken into
account.
Keep the "-upnp" option as a hidden arg for one major version in order
to show a more user friendly error to people who had this option set in
their config file.
33381ea530ad79ac1e04c37f5707e93d3e0509ca scripted-diff: Modernize nLocalServices to m_local_services (Fabian Jahr)
Pull request description:
The type of the `nLocalServices` variable was changed to `std::atomic<ServiceFlags>` in #30807 and I suggested the variable name to get updated with a scripted diff along with it. It wasn't included in the PR but I am still suggesting to do it as a follow-up since I had already prepared the commit.
ACKs for top commit:
sipa:
utACK 33381ea530ad79ac1e04c37f5707e93d3e0509ca
achow101:
ACK 33381ea530ad79ac1e04c37f5707e93d3e0509ca
furszy:
utACK 33381ea530ad79ac1e04c37f5707e93d3e0509ca
jonatack:
ACK 33381ea530ad79ac1e04c37f5707e93d3e0509ca
theStack:
ACK 33381ea530ad79ac1e04c37f5707e93d3e0509ca
Tree-SHA512: 407ea9eac694f079aa5b5c1611b5874d7a0897ba6bc3aa0570be94afe1bf3a826657b6890b6597c03c063e95b9dc868f0bdfbfc41e77ec7e06f5b045bf065c71
Because AssumeUTXO nodes prioritize tip synchronization, they relay their local
address through the network before completing the background chain sync.
This, combined with the advertising of full-node service (NODE_NETWORK), can
result in an honest peer in IBD connecting to the AssumeUTXO node (while syncing)
and requesting an historical block the node does not have. This behavior leads to
an abrupt disconnection due to perceived unresponsiveness (lack of response)
from the AssumeUTXO node.
This lack of response occurs because nodes ignore getdata requests when they do
not have the block data available (further discussion can be found in PR 30385).
Fix this by refraining from signaling full-node service support while the
background chain is being synced. During this period, the node will only
signal 'NODE_NETWORK_LIMITED' support. Then, full-node ('NODE_NETWORK')
support will be re-enabled once the background chain sync is completed.
6eeb188d40fe8f6c3b0a3be6dca519ea9a7b2358 test: adds seednode functional tests (Sergi Delgado Segura)
3270f0adad6ccbb8c004fb222f420e9b3ea32ea6 net: Favor peers from addrman over fetching seednodes (Sergi Delgado Segura)
Pull request description:
This is a follow-up of #28016 motivated by https://github.com/bitcoin/bitcoin/pull/28016#pullrequestreview-1913140932 and https://github.com/bitcoin/bitcoin/pull/28016#issuecomment-1984448937.
The current behavior of seednode fetching is pretty eager: we do it as the first step under `ThreadOpenNetworkConnections` even if some peers may be queryable from our addrman. This poses two potential issues:
- First, if permanently set (e.g. running with seednode in a config file) we'd be signaling such seed every time we restart our node
- Second, we will be giving the seed node way too much influence over our addrman, populating the latter with data from the former even when unnecessary
This changes the behavior to only add seednodes to `m_addr_fetch` if our addrman is empty, or little by little after we've spent some time trying addresses from our addrman. Also, seednodes are added to `m_addr_fetch` in random order, to avoid signaling the same node in case more than one seed is added and we happen to try them over multiple restarts
ACKs for top commit:
achow101:
ACK 6eeb188d40fe8f6c3b0a3be6dca519ea9a7b2358
cbergqvist:
ACK 6eeb188d40fe8f6c3b0a3be6dca519ea9a7b2358
itornaza:
Tested ACK 6eeb188d40fe8f6c3b0a3be6dca519ea9a7b2358
tdb3:
ACK 6eeb188d40fe8f6c3b0a3be6dca519ea9a7b2358
Tree-SHA512: b04445412f22018852d6bef4d3f1e88425ee6ddb434f61dcffa9e0c41b8e31f8c56f83858d5c7686289c86dc4c9476c437df15ea61a47082e2bb2e073cc62f15
189c987386a0da132d7ef076cdf539f9eb75fc3c Showing local addresses on the Node Window (Jadi)
a5d7aff867a3df9ac77664deed03e930e2636db0 net: Providing an interface for mapLocalHost (Jadi)
Pull request description:
This change adds a new row to the Node Window (debugwindow.ui)
under the Network section which shows the LocalAddresses.
fixes#564
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ACKs for top commit:
pablomartin4btc:
re-ACK 189c987386a0da132d7ef076cdf539f9eb75fc3c
furszy:
utACK 189c987
Tree-SHA512: 93f201bc6d21d81b27b87be050a447b841f01e3efb69b9eca2cc7af103023d7cd69eb5e16e2875855573ef51a5bf74a6ee6028636c1b6798cb4bb11567cb4996
Contributes to #564 by providing an interface for mapLocalHost
through net -> node interface -> clientModel. Later this value can be
read by GUI to show the local addresses.
The current behavior of seednode fetching is pretty eager: we do it as the first
step under `ThreadOpenNetworkConnections` even if some peers may be queryable
from our addrman. This poses two potential issues:
- First, if permanently set (e.g. running with seednode in a config file) we'd
be signaling such seed every time we restart our node
- Second, we will be giving the seed node way too much influence over our addrman,
populating the latter even with data from the former even when unnecessary
This changes the behavior to only add seednodes to `m_addr_fetch` if our addrman
is empty, or little by little after we've spent some time trying addresses from
our addrman. Also, seednodes are added to `m_addr_fetch` in random order, to avoid
signaling the same node in case more than one seed is added and we happen to try
them over multiple restarts
