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:
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kashifs:
> > tACK [0420f9](0420f99f42)
sr-gi:
> > > tACK [0420f9](0420f99f42)
mzumsande:
Tested ACK 0420f99f42
Tree-SHA512: a3a10e748c12d98d439dfb193c75bc8d9486717cda5f41560f5c0ace1baef523d001d5e7eabac9fa466a9159a30bb925cc1327c2d6c4efb89dcaf54e176d1752
df69b22f2e doc: improve documentation around connection limit maximums (Amiti Uttarwar)
adc171edf4 scripted-diff: Rename connection limit variables (Amiti Uttarwar)
e9fd9c0225 net: add m_max_inbound to connman (Amiti Uttarwar)
c25e0e0555 net, refactor: move calculations for connection type limits into connman (Amiti Uttarwar)
Pull request description:
This is joint work with amitiuttarwar.
This has the first few commits of #28463. It is not strictly a prerequisite for that, but has changes that in our opinion make sense on their own.
It improves the handling of maximum numbers for different connection types (that are set during init and don’t change after) by:
* moving all calculations into one place, `CConnMan::Init()`. Before, they were dispersed between `Init`, `CConnman::Init` and other parts of `CConnman`, resulting in some duplicated test code.
* removing the possibility of having a negative maximum of inbound connections, which is hard to argue about
* renaming of variables and doc improvements
ACKs for top commit:
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naumenkogs:
ACK df69b22f2e
achow101:
ACK df69b22f2e
Tree-SHA512: 913d56136bc1df739978de50db67302f88bac2a9d34748ae96763288d97093e998fc0f94f9b6eff12867712d7e86225af6128f4170bf2b5b8ab76f024870a22c
af0fca530e netbase: use reliable send() during SOCKS5 handshake (Vasil Dimov)
1b19d1117c sock: change Sock::SendComplete() to take Span (Vasil Dimov)
Pull request description:
The `Socks5()` function which does the SOCKS5 handshake with the SOCKS5 proxy sends bytes to the socket without retrying partial writes.
`send(2)` may write only part of the provided data and return. In this case the caller is responsible for retrying the operation with the remaining data. Change `Socks5()` to do that. There is already a method `Sock::SendComplete()` which does exactly that, so use it in `Socks5()`.
A minor complication for this PR is that `Sock::SendComplete()` takes `std::string` argument whereas `Socks5()` has `std::vector<uint8_t>`. Thus the necessity for the first commit. It is possible to do also in other ways - convert the data in `Socks5()` to `std::string` or have just one `Sock::SendComplete()` that takes `void*` and change the callers to pass `str.data(), str.size()` or `vec.data(), vec.size()`.
This came up while testing https://github.com/bitcoin/bitcoin/pull/27375.
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pinheadmz:
ACK af0fca530e
Tree-SHA512: 1d4a53d0628f7607378038ac56dc3b8624ce9322b034c9547a0c3ce052eafb4b18213f258aa3b57bcb4d990a5e0548a37ec70af2bd55f6e8e6399936f1ce047a
`send(2)` can be interrupted or for another reason it may not fully
complete sending all the bytes. We should be ready to retry the send
with the remaining bytes. This is what `Sock::SendComplete()` does,
thus use it in `Socks5()`.
Since `Sock::SendComplete()` takes a `CThreadInterrupt` argument,
change also the recv part of `Socks5()` to use `CThreadInterrupt`
instead of a boolean.
Easier reviewed with `git show -b` (ignore white-space changes).
`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.
Currently it is possible to add the same node twice when formatting IPs in
different, yet equivalent, manner. This applies to both ipv4 and ipv6, e.g:
127.0.0.1 = 127.1 | [::1] = [0:0:0:0:0:0:0:1]
`addnode` will accept both and display both as connected (given they translate to
the same IP). This will not result in multiple connections to the same node, but
will report redundant info when querying `getaddednodeinfo` and populate `m_added_nodes`
with redundant data.
This can be avoided performing comparing the contents of `m_added_addr` and the address
to be added as `CServices` instead of as strings.
The current `addnode` rpc command has some edge cases in where it is possible to
connect to the same node twice by combining ip and address requests. This can happen under two situations:
The two commands are run one right after each other, in which case they will be processed
under the same loop in `CConnman::ThreadOpenAddedConnections` without refreshing `vInfo`, so both
will go trough. An example of this would be:
```
bitcoin-cli addnode "localhost:port" add
```
A node is added by IP using `addnode "add"` while the other is added by name using
`addnode "onetry"` with an address that resolves to multiple IPs. In this case, we currently
only check one of the resolved IPs (picked at random), instead of all the resolved ones, meaning
this will only probabilistically fail/succeed. An example of this would be:
```
bitcoin-cli addnode "127.0.0.1:port" add
[...]
bitcoin-cli addnode "localhost:port" onetry
```
Both cases can be fixed by iterating over all resolved addresses in `CConnman::ConnectNode` instead
of picking one at random
5c8e15c451 i2p: destroy the session if we get an unexpected error from the I2P router (Vasil Dimov)
762404a68c i2p: also sleep after errors in Accept() (Vasil Dimov)
Pull request description:
### Background
In the `i2p::sam::Session` class:
`Listen()` does:
* if the session is not created yet
* create the control socket and on it:
* `HELLO`
* `SESSION CREATE ID=sessid`
* leave the control socked opened
* create a new socket and on it:
* `HELLO`
* `STREAM ACCEPT ID=sessid`
* read reply (`STREAM STATUS`), `Listen()` only succeeds if it contains `RESULT=OK`
Then a wait starts, for a peer to connect. When connected,
`Accept()` does:
* on the socket from `STREAM ACCEPT` from `Listen()`: read the Base64 identification of the connecting peer
### Problem
The I2P router may be in such a state that this happens in a quick succession (many times per second, see https://github.com/bitcoin/bitcoin/issues/22759#issuecomment-1609907115): `Listen()`-succeeds, `Accept()`-fails.
`Accept()` fails because the I2P router sends something that is not Base64 on the socket: `STREAM STATUS RESULT=I2P_ERROR MESSAGE="Session was closed"`
We only sleep after failed `Listen()` because the assumption was that if `Accept()` fails then the next `Listen()` will also fail.
### Solution
Avoid filling the log with "Error accepting:" messages and sleep also after a failed `Accept()`.
### Extra changes
* Reset the error waiting time after one successful connection. Otherwise the timer will remain high due to problems that have been solved long time in the past.
* Increment the wait time less aggressively.
* Handle the unexpected "Session was closed" message more gracefully (don't log stupid messages like `Cannot decode Base64: "STREAM STATUS...`) and destroy the session right way.
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re-ACK 5c8e15c451
Tree-SHA512: 1d47958c50eeae9eefcb668b8539fd092adead93328e4bf3355267819304b99ab41cbe1b5dbedbc3452c2bc389dc8330c0e27eb5ccb880e33dc46930a1592885
`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.
Background:
`Listen()` does:
* if the session is not created yet
* create the control socket and on it:
* `HELLO`
* `SESSION CREATE ID=sessid`
* leave the control socked opened
* create a new socket and on it:
* `HELLO`
* `STREAM ACCEPT ID=sessid`
* read reply (`STREAM STATUS`)
Then a wait starts, for a peer to connect. When connected,
`Accept()` does:
* on the socket from `STREAM ACCEPT` from `Listen()`: read the
Base64 identification of the connecting peer
Problem:
The I2P router may be in such a state that this happens in a quick
succession (many times per second, see https://github.com/bitcoin/bitcoin/issues/22759#issuecomment-1609907115):
`Listen()`-succeeds, `Accept()`-fails.
`Accept()` fails because the I2P router sends something that is
not Base64 on the socket:
STREAM STATUS RESULT=I2P_ERROR MESSAGE="Session was closed"
We only sleep after failed `Listen()` because the assumption was that
if `Accept()` fails then the next `Listen()` will also fail.
Solution:
Avoid filling the log with "Error accepting:" messages and sleep also
after a failed `Accept()`.
Extra changes:
* Reset the error waiting time after one successful connection.
Otherwise the timer will remain high due to problems that have
vanished long time ago.
* Increment the wait time less aggressively.
A "version" message in the V1 protocol starts with a fixed 16 bytes:
* The 4-byte network magic
* The 12-byte zero-padded command "version" plus 5 0x00 bytes
The current code detects incoming V1 connections by just looking at the
first 12 bytes (matching an earlier version of BIP324), but 16 bytes is
more precise. This isn't an observable difference right now, as a 12 byte
prefix ought to be negligible already, but it may become observable with
future extensions to the protocol, so make the code match the
specification.
Extract the logic for calculating & maintaining inbound connection limits to be
a member within connman for consistency with other maximum connection limits.
Note that we now limit m_max_inbound to 0 and don't call
AttemptToEvictConnection() when we don't have any inbounds.
Previously, nMaxInbound could become negative if the user ran with a low
-maxconnections, which didn't break any logic but didn't make sense.
Co-authored-by: Martin Zumsande <mzumsande@gmail.com>
7df4508369 test: improve sock_tests/move_assignment (Vasil Dimov)
5086a99b84 net: remove Sock default constructor, it's not necessary (Vasil Dimov)
7829272f78 net: remove now unnecessary Sock::Get() (Vasil Dimov)
944b21b70a net: don't check if the socket is valid in ConnectSocketDirectly() (Vasil Dimov)
aeac68d036 net: don't check if the socket is valid in GetBindAddress() (Vasil Dimov)
5ac1a51ee5 i2p: avoid using Sock::Get() for checking for a valid socket (Vasil Dimov)
Pull request description:
_This is a piece of #21878, chopped off to ease review._
Peeking at the underlying socket file descriptor of `Sock` and checkig if it is `INVALID_SOCKET` is bad encapsulation and stands in the way of testing/mocking/fuzzing.
Instead use an empty `unique_ptr` to denote that there is no valid socket where appropriate or outright remove such checks where they are not necessary.
The default constructor `Sock::Sock()` is unnecessary now after recent changes, thus remove it.
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Tree-SHA512: 9742aeeeabe8690530bf74caa6ba296787028c52f4a3342afd193b05dbbb1f6645935c33ba0a5230199a09af01c666bd3c7fb16b48692a0d185356ea59a8ddbf
When an outbound v2 connection is disconnected without receiving anything, but at
least 24 bytes of our pubkey were sent out (enough to constitute an invalid v1
header), add them to a queue of reconnections to be tried.
The reconnections are in a queue rather than performed immediately, because we should
not block the socket handler thread with connection creation (a blocking operation
that can take multiple seconds).
fac29a0ab1 Remove SER_GETHASH, hard-code client version in CKeyPool serialize (MarcoFalke)
fa72f09d6f Remove CHashWriter type (MarcoFalke)
fa4a9c0f43 Remove unused GetType() from OverrideStream, CVectorWriter, SpanReader (MarcoFalke)
Pull request description:
Removes a bunch of redundant, dead or duplicate code.
Uses the idea from and finishes the idea https://github.com/bitcoin/bitcoin/pull/28428 by theuni
ACKs for top commit:
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kevkevinpal:
added one nit but otherwise ACK [fac29a0](fac29a0ab1)
Tree-SHA512: cc805e2f38e73869a6691fdb5da09fa48524506b87fc93f05d32c336ad3033425a2d7608e317decd3141fde3f084403b8de280396c0c39132336fe0f7510af9e
See also https://github.com/bitcoin/bips/pull/1498
The benefit is a simpler implementation:
- The protocol state machine does not need separate states for garbage
authentication and version phases.
- The special case of "ignoring the ignore bit" is removed.
- The freedom to choose the contents of the garbage authentication
packet is removed. This simplifies testing.
3fcd7fc7ff Do not use std::vector = {} to release memory (Pieter Wuille)
Pull request description:
It appears that invoking `v = {};` for an `std::vector<...> v` is equivalent to `v.clear()`, which does not release its allocated memory. There are a number of places in the codebase where it appears to be used for that purpose however (mostly written by me). Replace those with `std::vector<...>{}.swap(v);` (using a helper function `ClearShrink` in util/vector.h).
To explain what is going on: `v = {...};` is equivalent in general to `v.operator=({...});`. For many types, the `{}` is converted to the type of `v`, and then assigned to `v` - which for `std::vector` would ordinarily have the effect of clearing its memory (constructing a new empty vector, and then move-assigning it to `v`). However, since `std::vector<T>` has an `operator=(std::initializer_list<T>)` defined, it has precedence (since no implicit conversion is needed), and with an empty list, that is equivalent to `clear()`.
I did consider using `v = std::vector<T>{};` as replacement for `v = {};` instances where memory releasing is desired, but it appears that it does not actually work universally either. `V{}.swap(v);` does.
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theStack:
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Tree-SHA512: 6148558126ec3c8cfd6daee167ec1c67b360cf1dff2cbc132bd71768337cf9bc4dda3e5a9cf7da4f7457d2123288eeba77dd78f3a17fa2cfd9c6758262950cc5
Move functions requiring the netaddress.h include out of
libbitcoinkernel source files.
The netaddress.h file contains many non-consensus related definitions
and should thus not be part of the libbitcoinkernel. This commit makes
netaddress.h no longer a required include for users of the
libbitcoinkernel.
This commit is part of the libbitcoinkernel project, namely its stage 1
step 3: Decouple most non-consensus headers from libbitcoinkernel.
The protocol.h file contains many non-consensus related definitions and
should thus not be part of the libbitcoinkernel. This commit makes
protocol.h no longer a required include for users of the
libbitcoinkernel.
This commit is part of the libbitcoinkernel project, namely its stage 1
step 3: Decouple most non-consensus headers from libbitcoinkernel.
Co-Authored-By: Cory Fields <cory-nospam-@coryfields.com>
Before this commit the V2Transport::m_send_buffer is used to store the
garbage:
* During MAYBE_V1 state, it's there despite not being sent.
* During AWAITING_KEY state, while it is being sent.
* At the end of the AWAITING_KEY state it cannot be wiped as it's still
needed to compute the garbage authentication packet.
Change this by introducing a separate m_send_garbage field, taking over
the first and last role listed above. This means the garbage is only in
the send buffer when it's actually being sent, removing a few special
cases related to this.
This removes the ability for BIP324Cipher to generate its own key, moving that
responsibility to the caller (mostly, V2Transport). This allows us to write
the random-key V2Transport constructor by delegating to the explicit-key one.
This introduces a V2Transport with a basic subset of BIP324 functionality:
* no ability to send garbage (but receiving is supported)
* no ability to send decoy packets (but receiving them is supported)
* no support for short message id encoding (neither encoding or decoding)
* no waiting until 12 non-V1 bytes have been received
* (and thus) no detection of V1 connections on the responder side
(on the sender side, detecting V1 is not supported either, but that needs
to be dealt with at a higher layer, by reconnecting)
Before this commit, there are only two possibly outcomes for the "more" prediction
in Transport::GetBytesToSend():
* true: the transport itself has more to send, so the answer is certainly yes.
* false: the transport has nothing further to send, but if vSendMsg has more message(s)
left, that still will result in more wire bytes after the next
SetMessageToSend().
For the BIP324 v2 transport, there will arguably be a third state:
* definitely not: the transport has nothing further to send, but even if vSendMsg has
more messages left, they can't be sent (right now). This happens
before the handshake is complete.
To implement this, we move the entire decision logic to the Transport, by adding a
boolean to GetBytesToSend(), called have_next_message, which informs the transport
whether more messages are available. The return values are still true and false, but
they mean "definitely yes" and "definitely no", rather than "yes" and "maybe".
This also cleans up the addrman (de)serialization code paths to only
allow `Disk` serialization. Some unit tests previously forced a
`Network` serialization, which does not make sense, because Bitcoin Core
in production will always `Disk` serialize.
This cleanup idea was suggested by Pieter Wuille and implemented by Anthony
Towns.
Co-authored-by: Pieter Wuille <pieter@wuille.net>
Co-authored-by: Anthony Towns <aj@erisian.com.au>
This furthers transport abstraction by removing the assumption that a message
can always immediately be converted to wire bytes. This assumption does not hold
for the v2 transport proposed by BIP324, as no messages can be sent before the
handshake completes.
This is done by only keeping (complete) CSerializedNetMsg objects in vSendMsg,
rather than the resulting bytes (for header and payload) that need to be sent.
In SocketSendData, these objects are handed to the transport as permitted by it,
and sending out the bytes the transport tells us to send. This also removes the
nSendOffset member variable in CNode, as keeping track of how much has been sent
is now a responsability of the transport.
This is not a pure refactor, and has the following effects even for the current
v1 transport:
* Checksum calculation now happens in SocketSendData rather than PushMessage.
For non-optimistic-send messages, that means this computation now happens in
the network thread rather than the message handler thread (generally a good
thing, as the message handler thread is more of a computational bottleneck).
* Checksum calculation now happens while holding the cs_vSend lock. This is
technically unnecessary for the v1 transport, as messages are encoded
independent from one another, but is untenable for the v2 transport anyway.
* Statistics updates about per-message sent bytes now happen when those bytes
are actually handed to the OS, rather than at PushMessage time.
This more accurately captures the intent of limiting send buffer size, as
many small messages can have a larger overhead that is not counted with the
current approach.
It also means removing the dependency on the header size (which will become
a function of the transport choice) from the send buffer calculations.
The rest of net.cpp already uses Params() to determine chainparams in many
places (and even V1Transport itself does so in some places).
Since the only chainparams dependency is through the message start characters,
just store those directly in the transport.
