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.
It is possible that the client disconnects before the request is
handled. In those cases, evhttp_request_set_on_complete_cb is never
called, which means that on shutdown the server we'll keep waiting
endlessly.
By adding evhttp_connection_set_closecb, libevent automatically
cleans up those dead connections at latest when we shutdown, and
depending on the libevent version already at the moment of remote
client disconnect. In both cases, the bug is fixed.
Introduces and uses a HTTPRequestTracker class to keep track of
how many HTTP requests are currently active, so we don't stop the
server before they're all handled.
This has two purposes:
1. In a next commit, allows us to untrack all requests associated
with a connection without running into lifetime issues of the
connection living longer than the request
(see https://github.com/bitcoin/bitcoin/pull/27909#discussion_r1265614783)
2. Improve encapsulation by making the mutex and cv internal members,
and exposing just the WaitUntilEmpty() method that can be safely
used.
79d343a642 http: update libevent workaround to correct version (stickies-v)
Pull request description:
The libevent bug described in 5ff8eb2637 was already patched in [release-2.1.9-beta](https://github.com/libevent/libevent/releases/tag/release-2.1.9-beta), with cherry-picked commits [5b40744d1581447f5b4496ee8d4807383e468e7a](5b40744d15) and [b25813800f97179b2355a7b4b3557e6a7f568df2](b25813800f).
There should be no side-effects by re-applying the workaround on an already patched version of libevent (as is currently done in master for people running libevent between 2.1.9 and 2.1.12), but it is best to just set the correct version number to avoid confusion.
This will prevent situations like e.g. in https://github.com/bitcoin/bitcoin/pull/27909#discussion_r1238858604, where a reverse workaround was incorrectly applied to the wrong version range.
ACKs for top commit:
fanquake:
ACK 79d343a642
Tree-SHA512: 56d2576411cf38e56d0976523fec951e032a48e35af293ed1ef3af820af940b26f779b9197baaed6d8b79bd1c7f7334646b9d73f80610d63cffbc955958ca8a0
The libevent bug described in 5ff8eb2637
was already patched in release-2.1.9-beta, with cherry-picked
commits 5b40744d1581447f5b4496ee8d4807383e468e7a and
b25813800f97179b2355a7b4b3557e6a7f568df2.
There should be no side-effects by re-applying the workaround on
an already patched version of libevent, but it is best to set the
correct version number to avoid confusion.
After initially being merged in #20487, it's no-longer clear that an
internal syscall sandboxing mechanism is something that Bitcoin Core
should have/maintain, especially when compared to better
maintained/supported alterantives, i.e firejail.
Note that given where it's used, the sandbox also gets dragged into the
kernel.
There is some related discussion in #24771.
This should not require any sort of deprecation, as this was only ever
an opt-in, experimental feature.
Closes#24771.
be55f545d5 move-only: Extract common/args and common/config.cpp from util/system (TheCharlatan)
Pull request description:
This pull request is part of the `libbitcoinkernel` project https://github.com/bitcoin/bitcoin/issues/24303https://github.com/bitcoin/bitcoin/projects/18 and more specifically its "Step 2: Decouple most non-consensus code from libbitcoinkernel". It is part of a series of patches splitting up the `util/system` files. Its preceding pull request is https://github.com/bitcoin/bitcoin/pull/27254.
The pull request contains an extraction of ArgsManager related functions from util/system into their own common/ file.
The background of this commit is an ongoing effort to decouple the libbitcoinkernel library from the ArgsManager. The ArgsManager belongs into the common library, since the kernel library should not depend on it. See [doc/design/libraries.md](https://github.com/bitcoin/bitcoin/blob/master/doc/design/libraries.md) for more information on this rationale.
ACKs for top commit:
MarcoFalke:
re-ACK be55f545d5🚲
ryanofsky:
Code review ACK be55f545d5. Just small cleanups since the last review.
hebasto:
ACK be55f545d5, I have reviewed the code and it looks OK, I agree it can be merged.
Tree-SHA512: 90eb03334af0155b823030b4f2ecf286d35058d700ee2ddbbaa445be19e31eb0fe982656f35bd14ecee3ad2c3d0db3746855cb8f3777eff7253713e42873e111
This is an extraction of ArgsManager related functions from util/system
into their own common file.
Config file related functions are moved to common/config.cpp.
The background of this commit is an ongoing effort to decouple the
libbitcoinkernel library from the ArgsManager. The ArgsManager belongs
into the common library, since the kernel library should not depend on
it. See doc/design/libraries.md for more information on this rationale.
`evhttp_uri_parse` can return a nullptr, for example when the URI
contains invalid characters (e.g. "%").
`GetQueryParameterFromUri` passes the output of `evhttp_uri_parse`
straight into `evhttp_uri_get_query`, which means that anyone calling
a REST endpoint in which query parameters are used (e.g. `rest_headers`)
can cause a segfault.
This bugfix is designed to be minimal and without additional behaviour change.
Follow-up work should be done to resolve this in a more general and robust way,
so not every endpoint has to handle it individually.
60978c8080 test: Reduce extended timeout on abortnode test (Fabian Jahr)
660bdbf785 http: Release server before waiting for event base loop exit (João Barbosa)
8c6d007c80 http: Track active requests and wait for last to finish (João Barbosa)
Pull request description:
This revives #19420. Since promag is not so active at the moment, I can support this to finally get it merged.
The PR is rebased and comments by jonatack have been addressed.
Once this is merged, I will also reopen#19434.
ACKs for top commit:
achow101:
ACK 60978c8080
stickies-v:
re-ACK [60978c8](60978c8080)
hebasto:
ACK 60978c8080
Tree-SHA512: eef0fe1081e9331b95cfafc71d82f2398abd1d3439dac5b2fa5c6d9c0a3f63ef19adde1c38c88d3b4e7fb41ce7c097943f1815c10e33d165918ccbdec512fe1c
c9d548c91f net: remove CService::ToStringPort() (Vasil Dimov)
fd4f0f41e9 gui: simplify OptionsDialog::updateDefaultProxyNets() (Vasil Dimov)
96c791dd20 net: remove CService::ToString() use ToStringAddrPort() instead (Vasil Dimov)
944a9de08a net: remove CNetAddr::ToString() and use ToStringAddr() instead (Vasil Dimov)
043b9de59a scripted-diff: rename ToStringIP[Port]() to ToStringAddr[Port]() (Vasil Dimov)
Pull request description:
Before this PR we had the somewhat confusing combination of methods:
`CNetAddr::ToStringIP()`
`CNetAddr::ToString()` (duplicate of the above)
`CService::ToStringIPPort()`
`CService::ToString()` (duplicate of the above, overrides a non-virtual method from `CNetAddr`)
`CService::ToStringPort()`
Avoid [overriding non-virtual methods](https://github.com/bitcoin/bitcoin/pull/25349/#issuecomment-1185226396).
"IP" stands for "Internet Protocol" and while sometimes "IP addresses" are called just "IPs", it is incorrect to call Tor or I2P addresses "IPs". Thus use "Addr" instead of "IP".
Change the above to:
`CNetAddr::ToStringAddr()`
`CService::ToStringAddrPort()`
The changes touch a lot of files, but are mostly mechanical.
ACKs for top commit:
sipa:
utACK c9d548c91f
achow101:
ACK c9d548c91f
jonatack:
re-ACK c9d548c91f only change since my previous reviews is rebase, but as a sanity check rebased to current master and at each commit quickly re-reviewed and re-verified clean build and green unit tests
LarryRuane:
ACK c9d548c91f
Tree-SHA512: 633fb044bdecf9f551b5e3314c385bf10e2b78e8027dc51ec324b66b018da35e5b01f3fbe6295bbc455ea1bcd1a3629de1918d28de510693afaf6a52693f2157
Both methods do the same thing, so simplify to having just one.
`ToString()` is too generic in this case and it is unclear what it does,
given that there are similar methods:
`ToStringAddr()` (inherited from `CNetAddr`),
`ToStringPort()` and
`ToStringAddrPort()`.
9d14f27bdd log: log RPC port on startup (James O'Beirne)
Pull request description:
I just spent a few hours trying to figure out why "18444" wasn't getting me to regtest's RPC server. I'm not the sharpest tool in the shed, but I was maybe understandably confused because "Bound to 127.0.0.1:18445" appears in the logs, which I assumed was the P2P port.
This change logs the RPC listening address by default on startup, which seems like a basic piece of information that shouldn't be buried under `-debug`.
ACKs for top commit:
dergoegge:
ACK 9d14f27bdd
jarolrod:
ACK 9d14f27bdd
aureleoules:
ACK 9d14f27bdd
Tree-SHA512: 5c86f018c0b8d6264abf878c921afe53033b23ab4cf289276bb1ed28fdf591c9d8871a4baa4098c363cb2aa9a637d2e4e18e56b14dfc7d767ee40757d7ff2e7c
I just spent a few hours trying to figure out why "18444" wasn't getting
me to regtest's RPC server. I'm not the sharpest tool in the shed, but I
was maybe understandably confused because "Bound to
127.0.0.1:18445" appears in the logs, which I assumed was the P2P port.
This change logs the RPC listening address, which seems like a basic
piece of information that shouldn't be buried in debug logs.
018d70b587 scripted-diff: Avoid incompatibility with CMake AUTOUIC feature (Hennadii Stepanov)
Pull request description:
Working on [migration](https://github.com/hebasto/bitcoin/pull/3) from Autotools to CMake build system, I found that our current code base needs to be adjusted.
CMake [allows](https://cmake.org/cmake/help/latest/prop_tgt/AUTOUIC.html) to
> handle the Qt `uic` code generator automatically
When using this feature, statements like `#include "ui_<ui_base>.h"` are processed in a special way.
The `node/ui_interface.h` unintentionally breaks this feature. Of course, it is possible to provide a list of source files to be excluded from `AUTOUIC`. But, unfortunately, this approach does not work for the `qt/sendcoinsdialog.cpp` source file, where there are both b71d37da2c/src/qt/sendcoinsdialog.cpp (L10) and b71d37da2c/src/qt/sendcoinsdialog.cpp (L24)
ACKs for top commit:
MarcoFalke:
cr ACK 018d70b587
ryanofsky:
Code review ACK 018d70b587
furszy:
Code review ACK 018d70b5
Tree-SHA512: 4fc83f2e5a82c8ab15c3c3d68f48b9863c47b96c0a66b6276b9b4dfc6063abffd73a16382acfe116553487b3ac697dbde2d9ada1b92010c5d8f8c6aa06f56428
Here we update only the log messages that manually print a category.
In upcoming commits, LogPrintCategory will likely be used in many
other cases, such as to replace `LogPrintf` where it makes sense.
This is more consistent with the other functions, as well as with the
logging output itself. If we want to make this change, we should do it
before it's all over the place.
The removed code was intended to catch issues with event_enable_debug_logging which was not available prior to libevent 2.1.1. This is not necessary since the minimum libevent version was bumped to 2.1.8.
c62d763fc3 Necessary improvements to make configure work without libevent installed (Perlover)
091ccc38c2 The evhttp_connection_get_peer function from libevent changes the type of the second parameter. Fixing the problem. (Perlover)
Pull request description:
The second parameter of evhttp_connection_get_peer in libevent already has type as `const char **`
The compilation of bitcoind with the fresh libevent occurs errors
Details: https://github.com/bitcoin/bitcoin/issues/23606
ACKs for top commit:
laanwj:
Code review ACK c62d763fc3
luke-jr:
tACK c62d763fc3
Tree-SHA512: d1c8062d90bd0d55c582dae2c3a7e5ee1b6c7ca872bf4aa7fe6f45a52ac4a8f59464215759d961f8efde0efbeeade31b08daf9387d7d50d7622baa1c06992d83
4747da3a5b Add syscall sandboxing (seccomp-bpf) (practicalswift)
Pull request description:
Add experimental syscall sandboxing using seccomp-bpf (Linux secure computing mode).
Enable filtering of system calls using seccomp-bpf: allow only explicitly allowlisted (expected) syscalls to be called.
The syscall sandboxing implemented in this PR is an experimental feature currently available only under Linux x86-64.
To enable the experimental syscall sandbox the `-sandbox=<mode>` option must be passed to `bitcoind`:
```
-sandbox=<mode>
Use the experimental syscall sandbox in the specified mode
(-sandbox=log-and-abort or -sandbox=abort). Allow only expected
syscalls to be used by bitcoind. Note that this is an
experimental new feature that may cause bitcoind to exit or crash
unexpectedly: use with caution. In the "log-and-abort" mode the
invocation of an unexpected syscall results in a debug handler
being invoked which will log the incident and terminate the
program (without executing the unexpected syscall). In the
"abort" mode the invocation of an unexpected syscall results in
the entire process being killed immediately by the kernel without
executing the unexpected syscall.
```
The allowed syscalls are defined on a per thread basis.
I've used this feature since summer 2020 and I find it to be a helpful testing/debugging addition which makes it much easier to reason about the actual capabilities required of each type of thread in Bitcoin Core.
---
Quick start guide:
```
$ ./configure
$ src/bitcoind -regtest -debug=util -sandbox=log-and-abort
…
2021-06-09T12:34:56Z Experimental syscall sandbox enabled (-sandbox=log-and-abort): bitcoind will terminate if an unexpected (not allowlisted) syscall is invoked.
…
2021-06-09T12:34:56Z Syscall filter installed for thread "addcon"
2021-06-09T12:34:56Z Syscall filter installed for thread "dnsseed"
2021-06-09T12:34:56Z Syscall filter installed for thread "net"
2021-06-09T12:34:56Z Syscall filter installed for thread "msghand"
2021-06-09T12:34:56Z Syscall filter installed for thread "opencon"
2021-06-09T12:34:56Z Syscall filter installed for thread "init"
…
# A simulated execve call to show the sandbox in action:
2021-06-09T12:34:56Z ERROR: The syscall "execve" (syscall number 59) is not allowed by the syscall sandbox in thread "msghand". Please report.
…
Aborted (core dumped)
$
```
---
[About seccomp and seccomp-bpf](https://en.wikipedia.org/wiki/Seccomp):
> In computer security, seccomp (short for secure computing mode) is a facility in the Linux kernel. seccomp allows a process to make a one-way transition into a "secure" state where it cannot make any system calls except exit(), sigreturn(), and read() and write() to already-open file descriptors. Should it attempt any other system calls, the kernel will terminate the process with SIGKILL or SIGSYS. In this sense, it does not virtualize the system's resources but isolates the process from them entirely.
>
> […]
>
> seccomp-bpf is an extension to seccomp that allows filtering of system calls using a configurable policy implemented using Berkeley Packet Filter rules. It is used by OpenSSH and vsftpd as well as the Google Chrome/Chromium web browsers on Chrome OS and Linux. (In this regard seccomp-bpf achieves similar functionality, but with more flexibility and higher performance, to the older systrace—which seems to be no longer supported for Linux.)
ACKs for top commit:
laanwj:
Code review and lightly tested ACK 4747da3a5b
Tree-SHA512: e1c28e323eb4409a46157b7cc0fc29a057ba58d1ee2de268962e2ade28ebd4421b5c2536c64a3af6e9bd3f54016600fec88d016adb49864b63edea51ad838e17
Improve readability of code, simplify future scripted diff cleanup PRs, and be
more consistent with naming for GetBoolArg.
This will also be useful for replacing runtime settings type checking
with compile time checking.
-BEGIN VERIFY SCRIPT-
git grep -l GetArg | xargs sed -i 's/GetArg(\([^)]*\( [0-9]\+\|-1\|port\|BaseParams().RPCPort()\|Params().GetDefaultPort()\|_TIMEOUT\|Height\|_WORKQUEUE\|_THREADS\|_CONNECTIONS\|LIMIT\|SigOp\|Bytes\|_VERSION\|_AGE\|_CHECKS\|Checks() ? 1 : 0\|_BANTIME\|Cache\|BLOCKS\|LEVEL\|Weight\|Version\|BUFFER\|TARGET\|WEIGHT\|TXN\|TRANSACTIONS\|ADJUSTMENT\|i64\|Size\|nDefault\|_EXPIRY\|HEIGHT\|SIZE\|SNDHWM\|_TIME_MS\)\))/GetIntArg(\1)/g'
-END VERIFY SCRIPT-
Co-authored-by: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
