0420f99f42 Create net_peer_connection unit tests (Jon Atack)
4b834f6499 Allow unit tests to access additional CConnman members (Jon Atack)
34b9ef443b net/rpc: Makes CConnman::GetAddedNodeInfo able to return only non-connected address on request (Sergi Delgado Segura)
94e8882d82 rpc: Prevents adding the same ip more than once when formatted differently (Sergi Delgado Segura)
2574b7e177 net/rpc: Check all resolved addresses in ConnectNode rather than just one (Sergi Delgado Segura)
Pull request description:
## Rationale
Currently, `addnode` has a couple of corner cases that allow it to either connect to the same peer more than once, hence wasting outbound connection slots, or add redundant information to `m_added_nodes`, hence making Bitcoin iterate through useless data on a regular basis.
### Connecting to the same node more than once
In general, connecting to the same node more than once is something we should try to prevent. Currently, this is possible via `addnode` in two different ways:
1. Calling `addnode` more than once in a short time period, using two equivalent but distinct addresses
2. Calling `addnode add` using an IP, and `addnode onetry` after with an address that resolved to the same IP
For the former, the issue boils down to `CConnman::ThreadOpenAddedConnections` calling `CConnman::GetAddedNodeInfo` once, and iterating over the result to open connections (`CConman::OpenNetworkConnection`) on the same loop for all addresses.`CConnman::ConnectNode` only checks a single address, at random, when resolving from a hostname, and uses it to check whether we are already connected to it.
An example to test this would be calling:
```
bitcoin-cli addnode "127.0.0.1:port" add
bitcoin-cli addnode "localhost:port" add
```
And check how it allows us to perform both connections some times, and some times it fails.
The latter boils down to the same issue, but takes advantage of `onetry` bypassing the `CConnman::ThreadOpenAddedConnections` logic and calling `CConnman::OpenNetworkConnection` straightaway. A way to test this would be:
```
bitcoin-cli addnode "127.0.0.1:port" add
bitcoin-cli addnode "localhost:port" onetry
```
### Adding the same peer with two different, yet equivalent, addresses
The current implementation of `addnode` is pretty naive when checking what data is added to `m_added_nodes`. Given the collection stores strings, the checks at `CConnman::AddNode()` basically check wether the exact provided string is already in the collection. If so, the data is rejected, otherwise, it is accepted. However, ips can be formatted in several ways that would bypass those checks.
Two examples would be `127.0.0.1` being equal to `127.1` and `[::1]` being equal to `[0:0:0:0:0:0:0:1]`. Adding any pair of these will be allowed by the rpc command, and both will be reported as connected by `getaddednodeinfo`, given they map to the same `CService`.
This is less severe than the previous issue, since even tough both nodes are reported as connected by `getaddednodeinfo`, there is only a single connection to them (as properly reported by `getpeerinfo`). However, this adds redundant data to `m_added_nodes`, which is undesirable.
### Parametrize `CConnman::GetAddedNodeInfo`
Finally, this PR also parametrizes `CConnman::GetAddedNodeInfo` so it returns either all added nodes info, or only info about the nodes we are **not** connected to. This method is used both for `rpc`, in `getaddednodeinfo`, in which we are reporting all data to the user, so the former applies, and to check what nodes we are not connected to, in `CConnman::ThreadOpenAddedConnections`, in which we are currently returning more data than needed and then actively filtering using `CService.fConnected()`
ACKs for top commit:
jonatack:
re-ACK 0420f99f42
kashifs:
> > tACK [0420f9](0420f99f42)
sr-gi:
> > > tACK [0420f9](0420f99f42)
mzumsande:
Tested ACK 0420f99f42
Tree-SHA512: a3a10e748c12d98d439dfb193c75bc8d9486717cda5f41560f5c0ace1baef523d001d5e7eabac9fa466a9159a30bb925cc1327c2d6c4efb89dcaf54e176d1752
bbb68ffdbd refactor: drop protocol.h include header in rpc/util.h (Jon Atack)
1dd62c5295 refactor: move GetServicesNames from rpc/util.{h,cpp} to rpc/net.cpp (Jon Atack)
Pull request description:
Move `GetServicesNames()` from `rpc/util` to `rpc/net.cpp`, as it is only called from that compilation unit and there is no reason for other ones to need it.
Remove the `protocol.h` include in `rpc/util.h`, as it was only needed for `GetServicesNames()`, drop an unneeded forward declaration (the other IWYU suggestions would require more extensive changes in other files), and add 3 already-missing include headers in other translation units that are needed to compile without `protocol.h` in `rpc/util.h`, as `protocol.h` includes `netaddress.h`, which in turn includes `util/strencodings.h`.
ACKs for top commit:
kevkevinpal:
lgtm ACK [bbb68ff](https://github.com/bitcoin/bitcoin/pull/28136/commits/bbb68ffdbdafb6717dcadac074f6098750b8aa77)
ns-xvrn:
ACK bbb68ff
achow101:
ACK bbb68ffdbd
Tree-SHA512: fcbe195874dd4aa9e86548685b6b28595a2c46f9869b79b6e2b3835f76b49cab4bef6a59c8ad6428063a41b7bb6f687229b06ea614fbd103e0531104af7de55d
`CConnman::GetAddedNodeInfo` is used both to get a list of addresses to manually connect to
in `CConnman::ThreadOpenAddedConnections`, and to report about manually added connections in
`getaddednodeinfo`. In both cases, all addresses added to `m_added_nodes` are returned, however
the nodes we are already connected to are only relevant to the latter, in the former they are
actively discarded.
Parametrizes `CConnman::GetAddedNodeInfo` so we can ask for only addresses we are not connected to,
to avoid passing useless information around.
fb3e812277 p2p: return `CSubNet` in `LookupSubNet` (brunoerg)
Pull request description:
Analyzing the usage of `LookupSubNet`, noticed that most cases uses check if the subnet is valid by calling `subnet.IsValid()`, and the boolean returned by `LookupSubNet` hasn't been used so much, see:
29d540b7ad/src/httpserver.cpp (L172-L174)29d540b7ad/src/net_permissions.cpp (L114-L116)
It makes sense to return `CSubNet` instead of `bool`.
ACKs for top commit:
achow101:
ACK fb3e812277
vasild:
ACK fb3e812277
theStack:
Code-review ACK fb3e812277
stickies-v:
Concept ACK, but Approach ~0 (for now). Reviewed the code (fb3e812277) and it all looks good to me.
Tree-SHA512: ba50d6bd5d58dfdbe1ce1faebd80dd8cf8c92ac53ef33519860b83399afffab482d5658cb6921b849d7a3df6d5cea911412850e08f3f4e27f7af510fbde4b254
0e6f6ebc06 net: remove unused CConnman::FindNode(const CSubNet&) (Vasil Dimov)
9482cb780f netbase: possibly change the result of LookupSubNet() to CJDNS (Vasil Dimov)
53afa68026 net: move MaybeFlipIPv6toCJDNS() from net to netbase (Vasil Dimov)
6e308651c4 net: move IsReachable() code to netbase and encapsulate it (Vasil Dimov)
c42ded3d9b fuzz: ConsumeNetAddr(): avoid IPv6 addresses that look like CJDNS (Vasil Dimov)
64d6f77907 net: put CJDNS prefix byte in a constant (Vasil Dimov)
Pull request description:
`LookupSubNet()` would treat addresses that start with `fc` as IPv6 even if `-cjdnsreachable` is set. This creates the following problems where it is called:
* `NetWhitelistPermissions::TryParse()`: otherwise `-whitelist=` fails to white list CJDNS addresses: when a CJDNS peer connects to us, it will be matched against IPv6 `fc...` subnet and the match will never succeed.
* `BanMapFromJson()`: CJDNS bans are stored as just IPv6 addresses in `banlist.json`. Upon reading from disk they have to be converted back to CJDNS, otherwise, after restart, a ban entry like (`fc00::1`, IPv6) would not match a peer (`fc00::1`, CJDNS).
* `RPCConsole::unbanSelectedNode()`: in the GUI the ban entries go through `CSubNet::ToString()` and back via `LookupSubNet()`. Then it must match whatever is stored in `BanMan`, otherwise it is impossible to unban via the GUI.
These were uncovered by https://github.com/bitcoin/bitcoin/pull/26859.
Thus, flip the result of `LookupSubNet()` to CJDNS if the network base address starts with `fc` and `-cjdnsreachable` is set. Since subnetting/masking does not make sense for CJDNS (the address is "random" bytes, like Tor and I2P, there is no hierarchy) treat `fc.../mask` as an invalid `CSubNet`.
To achieve that, `MaybeFlipIPv6toCJDNS()` has to be moved from `net` to `netbase` and thus also `IsReachable()`. In the process of moving `IsReachable()`, `SetReachable()` and `vfLimited[]` encapsulate those in a class.
ACKs for top commit:
jonatack:
Code review ACK 0e6f6ebc06
achow101:
ACK 0e6f6ebc06
mzumsande:
re-ACK 0e6f6ebc06
Tree-SHA512: 4767a60dc882916de4c8b110ce8de208ff3f58daaa0b560e6547d72e604d07c4157e72cf98b237228310fc05c0a3922f446674492e2ba02e990a272d288bd566
All callers of `LookupSubNet()` need the result to be of CJDNS type if
`-cjdnsreachable` is set and the address begins with `fc`:
* `NetWhitelistPermissions::TryParse()`: otherwise `-whitelist=` fails
to white list CJDNS addresses: when a CJDNS peer connects to us, it
will be matched against IPv6 `fc...` subnet and the match will never
succeed.
* `BanMapFromJson()`: CJDNS bans are stored as just IPv6 addresses in
`banlist.json`. Upon reading from disk they have to be converted back
to CJDNS, otherwise, after restart, a ban entry like (`fc00::1`, IPv6)
would not match a peer (`fc00::1`, CJDNS).
* `setban()` (in `rpc/net.cpp`): otherwise `setban fc.../mask add` would
add an IPv6 entry to BanMan. Subnetting does not make sense for CJDNS
addresses, thus treat `fc.../mask` as invalid `CSubNet`. The result of
`LookupHost()` has to be converted for the case of banning a single
host.
* `InitHTTPAllowList()`: not necessary since before this change
`-rpcallowip=fc...` would match IPv6 subnets against IPv6 peers even
if they started with `fc`. But because it is necessary for the above,
`HTTPRequest::GetPeer()` also has to be adjusted to return CJDNS peer,
so that now CJDNS peers are matched against CJDNS subnets.
`vfLimited`, `IsReachable()`, `SetReachable()` need not be in the `net`
module. Move them to `netbase` because they will be needed in
`LookupSubNet()` to possibly flip the result to CJDNS (if that network
is reachable).
In the process, encapsulate them in a class.
`NET_UNROUTABLE` and `NET_INTERNAL` are no longer ignored when adding
or removing reachable networks. This was unnecessary.
