highperfocused/bitcoin
1
0
Fork 0
mirror of https://github.com/bitcoin/bitcoin.git synced 2026-01-19 14:53:43 +01:00
Code Issues Packages Projects Releases Wiki Activity

Merge bitcoin/bitcoin#32539: init: Configure reachable networks before we start the RPC server

Browse Source 
12ff4be9c7 test: ensure -rpcallowip is compatible with RFC4193 (Matthew Zipkin)
c02bd3c187 config: Explain RFC4193 and CJDNS interaction in help and init error (Matthew Zipkin)
f728b6b111 init: Configure reachable networks before we start the RPC server (Matthew Zipkin)

Pull request description:

  Closes https://github.com/bitcoin/bitcoin/issues/32433

  `MaybeFlipIPv6toCJDNS()` relies on `g_reachable_nets` to distinguish between CJDNS addresses and other IPv6 addresses. In particular, [RFC4193](https://www.rfc-editor.org/rfc/rfc4193#section-3.1) address or "Unique Local Address" with the L-bit unset also begins with the `fc` prefix. #32433 highlights a use case for these addresses that have nothing to do with CJDNS.

  On master we don't parse init flags like `-cjdnsreachable` until *after* the HTTP server has started, causing conflicts with `-rpcallowip` because CJDNS doesn't support subnets.

  This PR ensures that `NET_CJDNS` is only present in the reachable networks list if set by `-cjdnsreachable` *before* `-rpcallowip` is checked. If it is set all `fc` addresses are assumed to be CJDNS, can not have subnets, and can't be set for `-rpcallowip`.

  I also noted this specific parameter interaction in the init help as well as the error message if configured incorrectly.

  This can be tested locally:

  `bitcoind -regtest -rpcallowip=fc00:dead:beef::/64 -rpcuser=u -rpcpassword=p`

  On master this will just throw an error that doesn't even mention IPv6 at all.

  On the branch, this will succeed and can be tested by adding the ULA to a local interface.

  On linux: `sudo ip -6 addr add fc00:dead:beef::1/64 dev lo`

  On macos: `sudo ifconfig lo0 inet6 fc00:dead:beef::1/128 add`

  then: `curl -v -g -6 --interface fc00:dead:beef::1 u:p@[::1]:18443 --data '{"method":"getblockcount"}'`

  If the `rpcallowip` option is removed, the RPC request will fail to authorize.

  Finally, adding `-cjdnsreachable` to the start up command will throw an error and specify the incompatibility:

  > RFC4193 is allowed only if -cjdnsreachable=0.

ACKs for top commit:
  achow101:
    ACK 12ff4be9c7
  tapcrafter:
    tACK 12ff4be9c7
  ryanofsky:
    Code review ACK 12ff4be9c7
  willcl-ark:
    ACK 12ff4be9c7

Tree-SHA512: a4dd70ca2bb9f6ec2c0a9463fd73985d1ed80552c674a9067ac9a86662d1c018cc275ba757cebb2993c5f3971ecf4778b95d35fe7a7178fb41b1d18b601c9960
This commit is contained in:
Ava Chow
2025-06-06 15:31:36 -07:00
parent 2053c43684 12ff4be9c7
commit e2174378aa
3 changed files with 49 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

52
src/init.cpp
View File

@@ -650,7 +650,7 @@ void SetupServerArgs(ArgsManager& argsman, bool can_listen_ipc)
argsman.AddArg("-blockversion=<n>", "Override block version to test forking scenarios", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::BLOCK_CREATION);
argsman.AddArg("-rest", strprintf("Accept public REST requests (default: %u)", DEFAULT_REST_ENABLE), ArgsManager::ALLOW_ANY, OptionsCategory::RPC);
argsman.AddArg("-rpcallowip=<ip>", "Allow JSON-RPC connections from specified source. Valid values for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0), a network/CIDR (e.g. 1.2.3.4/24), all ipv4 (0.0.0.0/0), or all ipv6 (::/0). This option can be specified multiple times", ArgsManager::ALLOW_ANY, OptionsCategory::RPC);
argsman.AddArg("-rpcallowip=<ip>", "Allow JSON-RPC connections from specified source. Valid values for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0), a network/CIDR (e.g. 1.2.3.4/24), all ipv4 (0.0.0.0/0), or all ipv6 (::/0). RFC4193 is allowed only if -cjdnsreachable=0. This option can be specified multiple times", ArgsManager::ALLOW_ANY, OptionsCategory::RPC);
argsman.AddArg("-rpcauth=<userpw>", "Username and HMAC-SHA-256 hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcauth. The client then connects normally using the rpcuser=<USERNAME>/rpcpassword=<PASSWORD> pair of arguments. This option can be specified multiple times", ArgsManager::ALLOW_ANY | ArgsManager::SENSITIVE, OptionsCategory::RPC);
argsman.AddArg("-rpcbind=<addr>[:port]", "Bind to given address to listen for JSON-RPC connections. Do not expose the RPC server to untrusted networks such as the public internet! This option is ignored unless -rpcallowip is also passed. Port is optional and overrides -rpcport. Use [host]:port notation for IPv6. This option can be specified multiple times (default: 127.0.0.1 and ::1 i.e., localhost)", ArgsManager::ALLOW_ANY | ArgsManager::NETWORK_ONLY, OptionsCategory::RPC);
argsman.AddArg("-rpcdoccheck", strprintf("Throw a non-fatal error at runtime if the documentation for an RPC is incorrect (default: %u)", DEFAULT_RPC_DOC_CHECK), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::RPC);
@@ -1392,6 +1392,32 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
// Check port numbers
if (!CheckHostPortOptions(args)) return false;
// Configure reachable networks before we start the RPC server.
// This is necessary for -rpcallowip to distinguish CJDNS from other RFC4193
const auto onlynets = args.GetArgs("-onlynet");
if (!onlynets.empty()) {
g_reachable_nets.RemoveAll();
for (const std::string& snet : onlynets) {
enum Network net = ParseNetwork(snet);
if (net == NET_UNROUTABLE)
return InitError(strprintf(_("Unknown network specified in -onlynet: '%s'"), snet));
g_reachable_nets.Add(net);
}
}
if (!args.IsArgSet("-cjdnsreachable")) {
if (!onlynets.empty() && g_reachable_nets.Contains(NET_CJDNS)) {
return InitError(
_("Outbound connections restricted to CJDNS (-onlynet=cjdns) but "
"-cjdnsreachable is not provided"));
}
g_reachable_nets.Remove(NET_CJDNS);
}
// Now g_reachable_nets.Contains(NET_CJDNS) is true if:
// 1. -cjdnsreachable is given and
// 2.1. -onlynet is not given or
// 2.2. -onlynet=cjdns is given
/* Start the RPC server already. It will be started in "warmup" mode
* and not really process calls already (but it will signify connections
* that the server is there and will be ready later). Warmup mode will
@@ -1504,30 +1530,6 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
strSubVersion.size(), MAX_SUBVERSION_LENGTH));
}
const auto onlynets = args.GetArgs("-onlynet");
if (!onlynets.empty()) {
g_reachable_nets.RemoveAll();
for (const std::string& snet : onlynets) {
enum Network net = ParseNetwork(snet);
if (net == NET_UNROUTABLE)
return InitError(strprintf(_("Unknown network specified in -onlynet: '%s'"), snet));
g_reachable_nets.Add(net);
}
}
if (!args.IsArgSet("-cjdnsreachable")) {
if (!onlynets.empty() && g_reachable_nets.Contains(NET_CJDNS)) {
return InitError(
_("Outbound connections restricted to CJDNS (-onlynet=cjdns) but "
"-cjdnsreachable is not provided"));
}
g_reachable_nets.Remove(NET_CJDNS);
}
// Now g_reachable_nets.Contains(NET_CJDNS) is true if:
// 1. -cjdnsreachable is given and
// 2.1. -onlynet is not given or
// 2.2. -onlynet=cjdns is given
// Requesting DNS seeds entails connecting to IPv4/IPv6, which -onlynet options may prohibit:
// If -dnsseed=1 is explicitly specified, abort. If it's left unspecified by the user, we skip
// the DNS seeds by adjusting -dnsseed in InitParameterInteraction.