Branch data Line data Source code
1 : : // Copyright (c) 2015-2022 The Bitcoin Core developers
2 : : // Distributed under the MIT software license, see the accompanying
3 : : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 : :
5 : : #if defined(HAVE_CONFIG_H)
6 : : #include <config/bitcoin-config.h>
7 : : #endif
8 : :
9 : : #include <httpserver.h>
10 : :
11 : : #include <chainparamsbase.h>
12 : : #include <common/args.h>
13 : : #include <compat/compat.h>
14 : : #include <logging.h>
15 : : #include <netbase.h>
16 : : #include <node/interface_ui.h>
17 : : #include <rpc/protocol.h> // For HTTP status codes
18 : : #include <sync.h>
19 : : #include <util/check.h>
20 : : #include <util/signalinterrupt.h>
21 : : #include <util/strencodings.h>
22 : : #include <util/threadnames.h>
23 : : #include <util/translation.h>
24 : :
25 : : #include <condition_variable>
26 : : #include <cstdio>
27 : : #include <cstdlib>
28 : : #include <deque>
29 : : #include <memory>
30 : : #include <optional>
31 : : #include <string>
32 : : #include <unordered_map>
33 : :
34 : : #include <sys/types.h>
35 : : #include <sys/stat.h>
36 : :
37 : : #include <event2/buffer.h>
38 : : #include <event2/bufferevent.h>
39 : : #include <event2/http.h>
40 : : #include <event2/http_struct.h>
41 : : #include <event2/keyvalq_struct.h>
42 : : #include <event2/thread.h>
43 : : #include <event2/util.h>
44 : :
45 : : #include <support/events.h>
46 : :
47 : : /** Maximum size of http request (request line + headers) */
48 : : static const size_t MAX_HEADERS_SIZE = 8192;
49 : :
50 : : /** HTTP request work item */
51 : 0 : class HTTPWorkItem final : public HTTPClosure
52 : : {
53 : : public:
54 : 0 : HTTPWorkItem(std::unique_ptr<HTTPRequest> _req, const std::string &_path, const HTTPRequestHandler& _func):
55 [ # # ][ # # ]: 0 : req(std::move(_req)), path(_path), func(_func)
56 : 0 : {
57 : 0 : }
58 : 0 : void operator()() override
59 : : {
60 : 0 : func(req.get(), path);
61 : 0 : }
62 : :
63 : : std::unique_ptr<HTTPRequest> req;
64 : :
65 : : private:
66 : : std::string path;
67 : : HTTPRequestHandler func;
68 : : };
69 : :
70 : : /** Simple work queue for distributing work over multiple threads.
71 : : * Work items are simply callable objects.
72 : : */
73 : : template <typename WorkItem>
74 : : class WorkQueue
75 : : {
76 : : private:
77 : : Mutex cs;
78 : : std::condition_variable cond GUARDED_BY(cs);
79 : : std::deque<std::unique_ptr<WorkItem>> queue GUARDED_BY(cs);
80 : 0 : bool running GUARDED_BY(cs){true};
81 : : const size_t maxDepth;
82 : :
83 : : public:
84 [ # # ]: 0 : explicit WorkQueue(size_t _maxDepth) : maxDepth(_maxDepth)
85 : : {
86 : 0 : }
87 : : /** Precondition: worker threads have all stopped (they have been joined).
88 : : */
89 : 0 : ~WorkQueue() = default;
90 : : /** Enqueue a work item */
91 : 0 : bool Enqueue(WorkItem* item) EXCLUSIVE_LOCKS_REQUIRED(!cs)
92 : : {
93 : 0 : LOCK(cs);
94 [ # # ][ # # ]: 0 : if (!running || queue.size() >= maxDepth) {
95 : 0 : return false;
96 : : }
97 [ # # ]: 0 : queue.emplace_back(std::unique_ptr<WorkItem>(item));
98 : 0 : cond.notify_one();
99 : 0 : return true;
100 : 0 : }
101 : : /** Thread function */
102 : 0 : void Run() EXCLUSIVE_LOCKS_REQUIRED(!cs)
103 : : {
104 : 0 : while (true) {
105 : 0 : std::unique_ptr<WorkItem> i;
106 : : {
107 [ # # ]: 0 : WAIT_LOCK(cs, lock);
108 [ # # ][ # # ]: 0 : while (running && queue.empty())
109 [ # # ]: 0 : cond.wait(lock);
110 [ # # ][ # # ]: 0 : if (!running && queue.empty())
111 : 0 : break;
112 : 0 : i = std::move(queue.front());
113 : 0 : queue.pop_front();
114 [ # # ]: 0 : }
115 [ # # ]: 0 : (*i)();
116 [ # # # ]: 0 : }
117 : 0 : }
118 : : /** Interrupt and exit loops */
119 : 0 : void Interrupt() EXCLUSIVE_LOCKS_REQUIRED(!cs)
120 : : {
121 : 0 : LOCK(cs);
122 : 0 : running = false;
123 : 0 : cond.notify_all();
124 : 0 : }
125 : : };
126 : :
127 : 0 : struct HTTPPathHandler
128 : : {
129 : 0 : HTTPPathHandler(std::string _prefix, bool _exactMatch, HTTPRequestHandler _handler):
130 [ # # ]: 0 : prefix(_prefix), exactMatch(_exactMatch), handler(_handler)
131 : : {
132 : 0 : }
133 : : std::string prefix;
134 : : bool exactMatch;
135 : : HTTPRequestHandler handler;
136 : : };
137 : :
138 : : /** HTTP module state */
139 : :
140 : : //! libevent event loop
141 : : static struct event_base* eventBase = nullptr;
142 : : //! HTTP server
143 : : static struct evhttp* eventHTTP = nullptr;
144 : : //! List of subnets to allow RPC connections from
145 : : static std::vector<CSubNet> rpc_allow_subnets;
146 : : //! Work queue for handling longer requests off the event loop thread
147 : : static std::unique_ptr<WorkQueue<HTTPClosure>> g_work_queue{nullptr};
148 : : //! Handlers for (sub)paths
149 : : static GlobalMutex g_httppathhandlers_mutex;
150 : : static std::vector<HTTPPathHandler> pathHandlers GUARDED_BY(g_httppathhandlers_mutex);
151 : : //! Bound listening sockets
152 : : static std::vector<evhttp_bound_socket *> boundSockets;
153 : :
154 : : /**
155 : : * @brief Helps keep track of open `evhttp_connection`s with active `evhttp_requests`
156 : : *
157 : : */
158 : 0 : class HTTPRequestTracker
159 : : {
160 : : private:
161 : : mutable Mutex m_mutex;
162 : : mutable std::condition_variable m_cv;
163 : : //! For each connection, keep a counter of how many requests are open
164 : : std::unordered_map<const evhttp_connection*, size_t> m_tracker GUARDED_BY(m_mutex);
165 : :
166 : 0 : void RemoveConnectionInternal(const decltype(m_tracker)::iterator it) EXCLUSIVE_LOCKS_REQUIRED(m_mutex)
167 : : {
168 : 0 : m_tracker.erase(it);
169 [ # # ]: 0 : if (m_tracker.empty()) m_cv.notify_all();
170 : 0 : }
171 : : public:
172 : : //! Increase request counter for the associated connection by 1
173 : 0 : void AddRequest(evhttp_request* req) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
174 : : {
175 : 0 : const evhttp_connection* conn{Assert(evhttp_request_get_connection(Assert(req)))};
176 [ # # ]: 0 : WITH_LOCK(m_mutex, ++m_tracker[conn]);
177 : 0 : }
178 : : //! Decrease request counter for the associated connection by 1, remove connection if counter is 0
179 : 0 : void RemoveRequest(evhttp_request* req) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
180 : : {
181 : 0 : const evhttp_connection* conn{Assert(evhttp_request_get_connection(Assert(req)))};
182 : 0 : LOCK(m_mutex);
183 [ # # ]: 0 : auto it{m_tracker.find(conn)};
184 [ # # ][ # # ]: 0 : if (it != m_tracker.end() && it->second > 0) {
185 [ # # ][ # # ]: 0 : if (--(it->second) == 0) RemoveConnectionInternal(it);
186 : 0 : }
187 : 0 : }
188 : : //! Remove a connection entirely
189 : 0 : void RemoveConnection(const evhttp_connection* conn) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
190 : : {
191 : 0 : LOCK(m_mutex);
192 [ # # ][ # # ]: 0 : auto it{m_tracker.find(Assert(conn))};
193 [ # # ][ # # ]: 0 : if (it != m_tracker.end()) RemoveConnectionInternal(it);
194 : 0 : }
195 : 0 : size_t CountActiveConnections() const EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
196 : : {
197 : 0 : return WITH_LOCK(m_mutex, return m_tracker.size());
198 : : }
199 : : //! Wait until there are no more connections with active requests in the tracker
200 : 0 : void WaitUntilEmpty() const EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
201 : : {
202 : 0 : WAIT_LOCK(m_mutex, lock);
203 [ # # ]: 0 : m_cv.wait(lock, [this]() EXCLUSIVE_LOCKS_REQUIRED(m_mutex) { return m_tracker.empty(); });
204 : 0 : }
205 : : };
206 : : //! Track active requests
207 : 2 : static HTTPRequestTracker g_requests;
208 : :
209 : : /** Check if a network address is allowed to access the HTTP server */
210 : 0 : static bool ClientAllowed(const CNetAddr& netaddr)
211 : : {
212 [ # # ]: 0 : if (!netaddr.IsValid())
213 : 0 : return false;
214 [ # # ]: 0 : for(const CSubNet& subnet : rpc_allow_subnets)
215 [ # # ]: 0 : if (subnet.Match(netaddr))
216 : 0 : return true;
217 : 0 : return false;
218 : 0 : }
219 : :
220 : : /** Initialize ACL list for HTTP server */
221 : 0 : static bool InitHTTPAllowList()
222 : : {
223 : 0 : rpc_allow_subnets.clear();
224 [ # # ][ # # ]: 0 : rpc_allow_subnets.emplace_back(LookupHost("127.0.0.1", false).value(), 8); // always allow IPv4 local subnet
[ # # ][ # # ]
[ # # ]
225 [ # # ][ # # ]: 0 : rpc_allow_subnets.emplace_back(LookupHost("::1", false).value()); // always allow IPv6 localhost
[ # # ][ # # ]
[ # # ]
226 [ # # ][ # # ]: 0 : for (const std::string& strAllow : gArgs.GetArgs("-rpcallowip")) {
[ # # ]
[ # # # ]
227 [ # # ]: 0 : const CSubNet subnet{LookupSubNet(strAllow)};
228 [ # # ][ # # ]: 0 : if (!subnet.IsValid()) {
229 [ # # ]: 0 : uiInterface.ThreadSafeMessageBox(
230 [ # # ][ # # ]: 0 : strprintf(Untranslated("Invalid -rpcallowip subnet specification: %s. Valid are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. 1.2.3.4/24)."), strAllow),
[ # # ]
231 [ # # ]: 0 : "", CClientUIInterface::MSG_ERROR);
232 : 0 : return false;
233 : : }
234 [ # # ]: 0 : rpc_allow_subnets.push_back(subnet);
235 [ # # ]: 0 : }
236 : 0 : std::string strAllowed;
237 [ # # ]: 0 : for (const CSubNet& subnet : rpc_allow_subnets)
238 [ # # ][ # # ]: 0 : strAllowed += subnet.ToString() + " ";
[ # # ]
239 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Allowing HTTP connections from: %s\n", strAllowed);
[ # # ][ # # ]
[ # # ]
240 : 0 : return true;
241 : 0 : }
242 : :
243 : : /** HTTP request method as string - use for logging only */
244 : 0 : std::string RequestMethodString(HTTPRequest::RequestMethod m)
245 : : {
246 [ # # # # : 0 : switch (m) {
# # ]
247 : : case HTTPRequest::GET:
248 [ # # ]: 0 : return "GET";
249 : : case HTTPRequest::POST:
250 [ # # ]: 0 : return "POST";
251 : : case HTTPRequest::HEAD:
252 [ # # ]: 0 : return "HEAD";
253 : : case HTTPRequest::PUT:
254 [ # # ]: 0 : return "PUT";
255 : : case HTTPRequest::UNKNOWN:
256 [ # # ]: 0 : return "unknown";
257 : : } // no default case, so the compiler can warn about missing cases
258 : 0 : assert(false);
259 : 0 : }
260 : :
261 : : /** HTTP request callback */
262 : 0 : static void http_request_cb(struct evhttp_request* req, void* arg)
263 : : {
264 : 0 : evhttp_connection* conn{evhttp_request_get_connection(req)};
265 : : // Track active requests
266 : : {
267 : 0 : g_requests.AddRequest(req);
268 : 0 : evhttp_request_set_on_complete_cb(req, [](struct evhttp_request* req, void*) {
269 : 0 : g_requests.RemoveRequest(req);
270 : 0 : }, nullptr);
271 : 0 : evhttp_connection_set_closecb(conn, [](evhttp_connection* conn, void* arg) {
272 : 0 : g_requests.RemoveConnection(conn);
273 : 0 : }, nullptr);
274 : : }
275 : :
276 : : // Disable reading to work around a libevent bug, fixed in 2.1.9
277 : : // See https://github.com/libevent/libevent/commit/5ff8eb26371c4dc56f384b2de35bea2d87814779
278 : : // and https://github.com/bitcoin/bitcoin/pull/11593.
279 [ # # ][ # # ]: 0 : if (event_get_version_number() >= 0x02010600 && event_get_version_number() < 0x02010900) {
280 [ # # ]: 0 : if (conn) {
281 : 0 : bufferevent* bev = evhttp_connection_get_bufferevent(conn);
282 [ # # ]: 0 : if (bev) {
283 : 0 : bufferevent_disable(bev, EV_READ);
284 : 0 : }
285 : 0 : }
286 : 0 : }
287 : 0 : auto hreq{std::make_unique<HTTPRequest>(req, *static_cast<const util::SignalInterrupt*>(arg))};
288 : :
289 : : // Early address-based allow check
290 [ # # ][ # # ]: 0 : if (!ClientAllowed(hreq->GetPeer())) {
[ # # ]
291 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "HTTP request from %s rejected: Client network is not allowed RPC access\n",
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ]
292 : : hreq->GetPeer().ToStringAddrPort());
293 [ # # ][ # # ]: 0 : hreq->WriteReply(HTTP_FORBIDDEN);
294 : 0 : return;
295 : : }
296 : :
297 : : // Early reject unknown HTTP methods
298 [ # # ][ # # ]: 0 : if (hreq->GetRequestMethod() == HTTPRequest::UNKNOWN) {
299 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "HTTP request from %s rejected: Unknown HTTP request method\n",
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ]
300 : : hreq->GetPeer().ToStringAddrPort());
301 [ # # ][ # # ]: 0 : hreq->WriteReply(HTTP_BAD_METHOD);
302 : 0 : return;
303 : : }
304 : :
305 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Received a %s request for %s from %s\n",
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
306 : : RequestMethodString(hreq->GetRequestMethod()), SanitizeString(hreq->GetURI(), SAFE_CHARS_URI).substr(0, 100), hreq->GetPeer().ToStringAddrPort());
307 : :
308 : : // Find registered handler for prefix
309 [ # # ]: 0 : std::string strURI = hreq->GetURI();
310 : 0 : std::string path;
311 [ # # ][ # # ]: 0 : LOCK(g_httppathhandlers_mutex);
312 : 0 : std::vector<HTTPPathHandler>::const_iterator i = pathHandlers.begin();
313 : 0 : std::vector<HTTPPathHandler>::const_iterator iend = pathHandlers.end();
314 [ # # ]: 0 : for (; i != iend; ++i) {
315 : 0 : bool match = false;
316 [ # # ]: 0 : if (i->exactMatch)
317 : 0 : match = (strURI == i->prefix);
318 : : else
319 [ # # ]: 0 : match = (strURI.substr(0, i->prefix.size()) == i->prefix);
320 [ # # ]: 0 : if (match) {
321 [ # # ]: 0 : path = strURI.substr(i->prefix.size());
322 : 0 : break;
323 : : }
324 : 0 : }
325 : :
326 : : // Dispatch to worker thread
327 [ # # ]: 0 : if (i != iend) {
328 [ # # ][ # # ]: 0 : std::unique_ptr<HTTPWorkItem> item(new HTTPWorkItem(std::move(hreq), path, i->handler));
[ # # ]
329 [ # # ]: 0 : assert(g_work_queue);
330 [ # # ][ # # ]: 0 : if (g_work_queue->Enqueue(item.get())) {
331 : 0 : item.release(); /* if true, queue took ownership */
332 : 0 : } else {
333 [ # # ][ # # ]: 0 : LogPrintf("WARNING: request rejected because http work queue depth exceeded, it can be increased with the -rpcworkqueue= setting\n");
[ # # ]
334 [ # # ][ # # ]: 0 : item->req->WriteReply(HTTP_SERVICE_UNAVAILABLE, "Work queue depth exceeded");
335 : : }
336 : 0 : } else {
337 [ # # ][ # # ]: 0 : hreq->WriteReply(HTTP_NOT_FOUND);
338 : : }
339 [ # # ]: 0 : }
340 : :
341 : : /** Callback to reject HTTP requests after shutdown. */
342 : 0 : static void http_reject_request_cb(struct evhttp_request* req, void*)
343 : : {
344 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Rejecting request while shutting down\n");
[ # # ][ # # ]
345 : 0 : evhttp_send_error(req, HTTP_SERVUNAVAIL, nullptr);
346 : 0 : }
347 : :
348 : : /** Event dispatcher thread */
349 : 0 : static void ThreadHTTP(struct event_base* base)
350 : : {
351 [ # # ][ # # ]: 0 : util::ThreadRename("http");
352 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Entering http event loop\n");
[ # # ][ # # ]
353 : 0 : event_base_dispatch(base);
354 : : // Event loop will be interrupted by InterruptHTTPServer()
355 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Exited http event loop\n");
[ # # ][ # # ]
356 : 0 : }
357 : :
358 : : /** Bind HTTP server to specified addresses */
359 : 0 : static bool HTTPBindAddresses(struct evhttp* http)
360 : : {
361 [ # # ][ # # ]: 0 : uint16_t http_port{static_cast<uint16_t>(gArgs.GetIntArg("-rpcport", BaseParams().RPCPort()))};
[ # # ][ # # ]
362 : 0 : std::vector<std::pair<std::string, uint16_t>> endpoints;
363 : :
364 : : // Determine what addresses to bind to
365 [ # # ][ # # ]: 0 : if (!(gArgs.IsArgSet("-rpcallowip") && gArgs.IsArgSet("-rpcbind"))) { // Default to loopback if not allowing external IPs
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
[ # # ][ # # ]
366 [ # # ]: 0 : endpoints.emplace_back("::1", http_port);
367 [ # # ]: 0 : endpoints.emplace_back("127.0.0.1", http_port);
368 [ # # ][ # # ]: 0 : if (gArgs.IsArgSet("-rpcallowip")) {
[ # # ]
369 [ # # ][ # # ]: 0 : LogPrintf("WARNING: option -rpcallowip was specified without -rpcbind; this doesn't usually make sense\n");
[ # # ]
370 : 0 : }
371 [ # # ][ # # ]: 0 : if (gArgs.IsArgSet("-rpcbind")) {
[ # # ]
372 [ # # ][ # # ]: 0 : LogPrintf("WARNING: option -rpcbind was ignored because -rpcallowip was not specified, refusing to allow everyone to connect\n");
[ # # ]
373 : 0 : }
374 [ # # ][ # # ]: 0 : } else if (gArgs.IsArgSet("-rpcbind")) { // Specific bind address
[ # # ]
375 [ # # ][ # # ]: 0 : for (const std::string& strRPCBind : gArgs.GetArgs("-rpcbind")) {
[ # # ]
376 : 0 : uint16_t port{http_port};
377 : 0 : std::string host;
378 [ # # ]: 0 : SplitHostPort(strRPCBind, port, host);
379 [ # # ]: 0 : endpoints.emplace_back(host, port);
380 : 0 : }
381 : 0 : }
382 : :
383 : : // Bind addresses
384 [ # # ]: 0 : for (std::vector<std::pair<std::string, uint16_t> >::iterator i = endpoints.begin(); i != endpoints.end(); ++i) {
385 [ # # ][ # # ]: 0 : LogPrintf("Binding RPC on address %s port %i\n", i->first, i->second);
[ # # ]
386 [ # # ][ # # ]: 0 : evhttp_bound_socket *bind_handle = evhttp_bind_socket_with_handle(http, i->first.empty() ? nullptr : i->first.c_str(), i->second);
387 [ # # ]: 0 : if (bind_handle) {
388 [ # # ][ # # ]: 0 : const std::optional<CNetAddr> addr{LookupHost(i->first, false)};
389 [ # # ][ # # ]: 0 : if (i->first.empty() || (addr.has_value() && addr->IsBindAny())) {
[ # # ][ # # ]
390 [ # # ][ # # ]: 0 : LogPrintf("WARNING: the RPC server is not safe to expose to untrusted networks such as the public internet\n");
[ # # ]
391 : 0 : }
392 [ # # ]: 0 : boundSockets.push_back(bind_handle);
393 : 0 : } else {
394 [ # # ][ # # ]: 0 : LogPrintf("Binding RPC on address %s port %i failed.\n", i->first, i->second);
[ # # ]
395 : : }
396 : 0 : }
397 : 0 : return !boundSockets.empty();
398 : 0 : }
399 : :
400 : : /** Simple wrapper to set thread name and run work queue */
401 : 0 : static void HTTPWorkQueueRun(WorkQueue<HTTPClosure>* queue, int worker_num)
402 : : {
403 [ # # ]: 0 : util::ThreadRename(strprintf("httpworker.%i", worker_num));
404 : 0 : queue->Run();
405 : 0 : }
406 : :
407 : : /** libevent event log callback */
408 : 0 : static void libevent_log_cb(int severity, const char *msg)
409 : : {
410 : : BCLog::Level level;
411 [ # # # # ]: 0 : switch (severity) {
412 : : case EVENT_LOG_DEBUG:
413 : 0 : level = BCLog::Level::Debug;
414 : 0 : break;
415 : : case EVENT_LOG_MSG:
416 : 0 : level = BCLog::Level::Info;
417 : 0 : break;
418 : : case EVENT_LOG_WARN:
419 : 0 : level = BCLog::Level::Warning;
420 : 0 : break;
421 : : default: // EVENT_LOG_ERR and others are mapped to error
422 : 0 : level = BCLog::Level::Error;
423 : 0 : break;
424 : : }
425 [ # # ][ # # ]: 0 : LogPrintLevel(BCLog::LIBEVENT, level, "%s\n", msg);
[ # # ][ # # ]
426 : 0 : }
427 : :
428 : 0 : bool InitHTTPServer(const util::SignalInterrupt& interrupt)
429 : : {
430 [ # # ]: 0 : if (!InitHTTPAllowList())
431 : 0 : return false;
432 : :
433 : : // Redirect libevent's logging to our own log
434 : 0 : event_set_log_callback(&libevent_log_cb);
435 : : // Update libevent's log handling.
436 : 0 : UpdateHTTPServerLogging(LogInstance().WillLogCategory(BCLog::LIBEVENT));
437 : :
438 : : #ifdef WIN32
439 : : evthread_use_windows_threads();
440 : : #else
441 : 0 : evthread_use_pthreads();
442 : : #endif
443 : :
444 : 0 : raii_event_base base_ctr = obtain_event_base();
445 : :
446 : : /* Create a new evhttp object to handle requests. */
447 [ # # ]: 0 : raii_evhttp http_ctr = obtain_evhttp(base_ctr.get());
448 : 0 : struct evhttp* http = http_ctr.get();
449 [ # # ]: 0 : if (!http) {
450 [ # # ][ # # ]: 0 : LogPrintf("couldn't create evhttp. Exiting.\n");
[ # # ]
451 : 0 : return false;
452 : : }
453 : :
454 [ # # ][ # # ]: 0 : evhttp_set_timeout(http, gArgs.GetIntArg("-rpcservertimeout", DEFAULT_HTTP_SERVER_TIMEOUT));
[ # # ]
455 [ # # ]: 0 : evhttp_set_max_headers_size(http, MAX_HEADERS_SIZE);
456 [ # # ]: 0 : evhttp_set_max_body_size(http, MAX_SIZE);
457 [ # # ]: 0 : evhttp_set_gencb(http, http_request_cb, (void*)&interrupt);
458 : :
459 [ # # ][ # # ]: 0 : if (!HTTPBindAddresses(http)) {
460 [ # # ][ # # ]: 0 : LogPrintf("Unable to bind any endpoint for RPC server\n");
[ # # ]
461 : 0 : return false;
462 : : }
463 : :
464 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Initialized HTTP server\n");
[ # # ][ # # ]
[ # # ]
465 [ # # ][ # # ]: 0 : int workQueueDepth = std::max((long)gArgs.GetIntArg("-rpcworkqueue", DEFAULT_HTTP_WORKQUEUE), 1L);
[ # # ]
466 [ # # ][ # # ]: 0 : LogPrintfCategory(BCLog::HTTP, "creating work queue of depth %d\n", workQueueDepth);
[ # # ]
467 : :
468 [ # # ]: 0 : g_work_queue = std::make_unique<WorkQueue<HTTPClosure>>(workQueueDepth);
469 : : // transfer ownership to eventBase/HTTP via .release()
470 : 0 : eventBase = base_ctr.release();
471 : 0 : eventHTTP = http_ctr.release();
472 : 0 : return true;
473 : 0 : }
474 : :
475 : 0 : void UpdateHTTPServerLogging(bool enable) {
476 [ # # ]: 0 : if (enable) {
477 : 0 : event_enable_debug_logging(EVENT_DBG_ALL);
478 : 0 : } else {
479 : 0 : event_enable_debug_logging(EVENT_DBG_NONE);
480 : : }
481 : 0 : }
482 : :
483 : 2 : static std::thread g_thread_http;
484 : : static std::vector<std::thread> g_thread_http_workers;
485 : :
486 : 0 : void StartHTTPServer()
487 : : {
488 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Starting HTTP server\n");
[ # # ][ # # ]
489 [ # # ][ # # ]: 0 : int rpcThreads = std::max((long)gArgs.GetIntArg("-rpcthreads", DEFAULT_HTTP_THREADS), 1L);
[ # # ]
490 [ # # ][ # # ]: 0 : LogPrintfCategory(BCLog::HTTP, "starting %d worker threads\n", rpcThreads);
[ # # ]
491 : 0 : g_thread_http = std::thread(ThreadHTTP, eventBase);
492 : :
493 [ # # ]: 0 : for (int i = 0; i < rpcThreads; i++) {
494 : 0 : g_thread_http_workers.emplace_back(HTTPWorkQueueRun, g_work_queue.get(), i);
495 : 0 : }
496 : 0 : }
497 : :
498 : 0 : void InterruptHTTPServer()
499 : : {
500 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Interrupting HTTP server\n");
[ # # ][ # # ]
501 [ # # ]: 0 : if (eventHTTP) {
502 : : // Reject requests on current connections
503 : 0 : evhttp_set_gencb(eventHTTP, http_reject_request_cb, nullptr);
504 : 0 : }
505 [ # # ]: 0 : if (g_work_queue) {
506 : 0 : g_work_queue->Interrupt();
507 : 0 : }
508 : 0 : }
509 : :
510 : 0 : void StopHTTPServer()
511 : : {
512 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Stopping HTTP server\n");
[ # # ][ # # ]
513 [ # # ]: 0 : if (g_work_queue) {
514 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Waiting for HTTP worker threads to exit\n");
[ # # ][ # # ]
515 [ # # ]: 0 : for (auto& thread : g_thread_http_workers) {
516 : 0 : thread.join();
517 : : }
518 : 0 : g_thread_http_workers.clear();
519 : 0 : }
520 : : // Unlisten sockets, these are what make the event loop running, which means
521 : : // that after this and all connections are closed the event loop will quit.
522 [ # # ]: 0 : for (evhttp_bound_socket *socket : boundSockets) {
523 : 0 : evhttp_del_accept_socket(eventHTTP, socket);
524 : : }
525 : 0 : boundSockets.clear();
526 : : {
527 [ # # ]: 0 : if (const auto n_connections{g_requests.CountActiveConnections()}; n_connections != 0) {
528 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Waiting for %d connections to stop HTTP server\n", n_connections);
[ # # ][ # # ]
529 : 0 : }
530 : 0 : g_requests.WaitUntilEmpty();
531 : : }
532 [ # # ]: 0 : if (eventHTTP) {
533 : : // Schedule a callback to call evhttp_free in the event base thread, so
534 : : // that evhttp_free does not need to be called again after the handling
535 : : // of unfinished request connections that follows.
536 : 0 : event_base_once(eventBase, -1, EV_TIMEOUT, [](evutil_socket_t, short, void*) {
537 : 0 : evhttp_free(eventHTTP);
538 : 0 : eventHTTP = nullptr;
539 : 0 : }, nullptr, nullptr);
540 : 0 : }
541 [ # # ]: 0 : if (eventBase) {
542 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Waiting for HTTP event thread to exit\n");
[ # # ][ # # ]
543 [ # # ]: 0 : if (g_thread_http.joinable()) g_thread_http.join();
544 : 0 : event_base_free(eventBase);
545 : 0 : eventBase = nullptr;
546 : 0 : }
547 : 0 : g_work_queue.reset();
548 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Stopped HTTP server\n");
[ # # ][ # # ]
549 : 0 : }
550 : :
551 : 0 : struct event_base* EventBase()
552 : : {
553 : 0 : return eventBase;
554 : : }
555 : :
556 : 0 : static void httpevent_callback_fn(evutil_socket_t, short, void* data)
557 : : {
558 : : // Static handler: simply call inner handler
559 : 0 : HTTPEvent *self = static_cast<HTTPEvent*>(data);
560 : 0 : self->handler();
561 [ # # ]: 0 : if (self->deleteWhenTriggered)
562 [ # # ]: 0 : delete self;
563 : 0 : }
564 : :
565 : 0 : HTTPEvent::HTTPEvent(struct event_base* base, bool _deleteWhenTriggered, const std::function<void()>& _handler):
566 : 0 : deleteWhenTriggered(_deleteWhenTriggered), handler(_handler)
567 : : {
568 [ # # ]: 0 : ev = event_new(base, -1, 0, httpevent_callback_fn, this);
569 [ # # ]: 0 : assert(ev);
570 : 0 : }
571 : 0 : HTTPEvent::~HTTPEvent()
572 : : {
573 [ # # ]: 0 : event_free(ev);
574 : 0 : }
575 : 0 : void HTTPEvent::trigger(struct timeval* tv)
576 : : {
577 [ # # ]: 0 : if (tv == nullptr)
578 : 0 : event_active(ev, 0, 0); // immediately trigger event in main thread
579 : : else
580 : 0 : evtimer_add(ev, tv); // trigger after timeval passed
581 : 0 : }
582 : 0 : HTTPRequest::HTTPRequest(struct evhttp_request* _req, const util::SignalInterrupt& interrupt, bool _replySent)
583 : 0 : : req(_req), m_interrupt(interrupt), replySent(_replySent)
584 : : {
585 : 0 : }
586 : :
587 : 0 : HTTPRequest::~HTTPRequest()
588 : : {
589 [ # # ]: 0 : if (!replySent) {
590 : : // Keep track of whether reply was sent to avoid request leaks
591 [ # # ][ # # ]: 0 : LogPrintf("%s: Unhandled request\n", __func__);
[ # # ]
592 [ # # ][ # # ]: 0 : WriteReply(HTTP_INTERNAL_SERVER_ERROR, "Unhandled request");
593 : 0 : }
594 : : // evhttpd cleans up the request, as long as a reply was sent.
595 : 0 : }
596 : :
597 : 0 : std::pair<bool, std::string> HTTPRequest::GetHeader(const std::string& hdr) const
598 : : {
599 : 0 : const struct evkeyvalq* headers = evhttp_request_get_input_headers(req);
600 [ # # ]: 0 : assert(headers);
601 : 0 : const char* val = evhttp_find_header(headers, hdr.c_str());
602 [ # # ]: 0 : if (val)
603 : 0 : return std::make_pair(true, val);
604 : : else
605 : 0 : return std::make_pair(false, "");
606 : 0 : }
607 : :
608 : 0 : std::string HTTPRequest::ReadBody()
609 : : {
610 : 0 : struct evbuffer* buf = evhttp_request_get_input_buffer(req);
611 [ # # ]: 0 : if (!buf)
612 [ # # ]: 0 : return "";
613 : 0 : size_t size = evbuffer_get_length(buf);
614 : : /** Trivial implementation: if this is ever a performance bottleneck,
615 : : * internal copying can be avoided in multi-segment buffers by using
616 : : * evbuffer_peek and an awkward loop. Though in that case, it'd be even
617 : : * better to not copy into an intermediate string but use a stream
618 : : * abstraction to consume the evbuffer on the fly in the parsing algorithm.
619 : : */
620 : 0 : const char* data = (const char*)evbuffer_pullup(buf, size);
621 [ # # ]: 0 : if (!data) // returns nullptr in case of empty buffer
622 [ # # ]: 0 : return "";
623 [ # # ]: 0 : std::string rv(data, size);
624 [ # # ]: 0 : evbuffer_drain(buf, size);
625 : 0 : return rv;
626 [ # # ]: 0 : }
627 : :
628 : 0 : void HTTPRequest::WriteHeader(const std::string& hdr, const std::string& value)
629 : : {
630 : 0 : struct evkeyvalq* headers = evhttp_request_get_output_headers(req);
631 [ # # ]: 0 : assert(headers);
632 : 0 : evhttp_add_header(headers, hdr.c_str(), value.c_str());
633 : 0 : }
634 : :
635 : : /** Closure sent to main thread to request a reply to be sent to
636 : : * a HTTP request.
637 : : * Replies must be sent in the main loop in the main http thread,
638 : : * this cannot be done from worker threads.
639 : : */
640 : 0 : void HTTPRequest::WriteReply(int nStatus, const std::string& strReply)
641 : : {
642 [ # # ][ # # ]: 0 : assert(!replySent && req);
643 [ # # ]: 0 : if (m_interrupt) {
644 [ # # ][ # # ]: 0 : WriteHeader("Connection", "close");
[ # # ]
645 : 0 : }
646 : : // Send event to main http thread to send reply message
647 : 0 : struct evbuffer* evb = evhttp_request_get_output_buffer(req);
648 [ # # ]: 0 : assert(evb);
649 : 0 : evbuffer_add(evb, strReply.data(), strReply.size());
650 : 0 : auto req_copy = req;
651 [ # # ][ # # ]: 0 : HTTPEvent* ev = new HTTPEvent(eventBase, true, [req_copy, nStatus]{
652 : 0 : evhttp_send_reply(req_copy, nStatus, nullptr, nullptr);
653 : : // Re-enable reading from the socket. This is the second part of the libevent
654 : : // workaround above.
655 [ # # ][ # # ]: 0 : if (event_get_version_number() >= 0x02010600 && event_get_version_number() < 0x02010900) {
656 : 0 : evhttp_connection* conn = evhttp_request_get_connection(req_copy);
657 [ # # ]: 0 : if (conn) {
658 : 0 : bufferevent* bev = evhttp_connection_get_bufferevent(conn);
659 [ # # ]: 0 : if (bev) {
660 : 0 : bufferevent_enable(bev, EV_READ | EV_WRITE);
661 : 0 : }
662 : 0 : }
663 : 0 : }
664 : 0 : });
665 : 0 : ev->trigger(nullptr);
666 : 0 : replySent = true;
667 : 0 : req = nullptr; // transferred back to main thread
668 : 0 : }
669 : :
670 : 0 : CService HTTPRequest::GetPeer() const
671 : : {
672 : 0 : evhttp_connection* con = evhttp_request_get_connection(req);
673 : 0 : CService peer;
674 [ # # ]: 0 : if (con) {
675 : : // evhttp retains ownership over returned address string
676 : 0 : const char* address = "";
677 : 0 : uint16_t port = 0;
678 : :
679 : : #ifdef HAVE_EVHTTP_CONNECTION_GET_PEER_CONST_CHAR
680 : : evhttp_connection_get_peer(con, &address, &port);
681 : : #else
682 [ # # ]: 0 : evhttp_connection_get_peer(con, (char**)&address, &port);
683 : : #endif // HAVE_EVHTTP_CONNECTION_GET_PEER_CONST_CHAR
684 : :
685 [ # # ][ # # ]: 0 : peer = MaybeFlipIPv6toCJDNS(LookupNumeric(address, port));
[ # # ][ # # ]
686 : 0 : }
687 : 0 : return peer;
688 [ # # ]: 0 : }
689 : :
690 : 0 : std::string HTTPRequest::GetURI() const
691 : : {
692 [ # # ]: 0 : return evhttp_request_get_uri(req);
693 : 0 : }
694 : :
695 : 0 : HTTPRequest::RequestMethod HTTPRequest::GetRequestMethod() const
696 : : {
697 [ # # # # : 0 : switch (evhttp_request_get_command(req)) {
# ]
698 : : case EVHTTP_REQ_GET:
699 : 0 : return GET;
700 : : case EVHTTP_REQ_POST:
701 : 0 : return POST;
702 : : case EVHTTP_REQ_HEAD:
703 : 0 : return HEAD;
704 : : case EVHTTP_REQ_PUT:
705 : 0 : return PUT;
706 : : default:
707 : 0 : return UNKNOWN;
708 : : }
709 : 0 : }
710 : :
711 : 0 : std::optional<std::string> HTTPRequest::GetQueryParameter(const std::string& key) const
712 : : {
713 : 0 : const char* uri{evhttp_request_get_uri(req)};
714 : :
715 : 0 : return GetQueryParameterFromUri(uri, key);
716 : : }
717 : :
718 : 0 : std::optional<std::string> GetQueryParameterFromUri(const char* uri, const std::string& key)
719 : : {
720 : 0 : evhttp_uri* uri_parsed{evhttp_uri_parse(uri)};
721 [ # # ]: 0 : if (!uri_parsed) {
722 [ # # ]: 0 : throw std::runtime_error("URI parsing failed, it likely contained RFC 3986 invalid characters");
723 : : }
724 : 0 : const char* query{evhttp_uri_get_query(uri_parsed)};
725 : 0 : std::optional<std::string> result;
726 : :
727 [ # # ]: 0 : if (query) {
728 : : // Parse the query string into a key-value queue and iterate over it
729 : : struct evkeyvalq params_q;
730 [ # # ]: 0 : evhttp_parse_query_str(query, ¶ms_q);
731 : :
732 [ # # ]: 0 : for (struct evkeyval* param{params_q.tqh_first}; param != nullptr; param = param->next.tqe_next) {
733 [ # # ][ # # ]: 0 : if (param->key == key) {
734 [ # # ]: 0 : result = param->value;
735 : 0 : break;
736 : : }
737 : 0 : }
738 [ # # ]: 0 : evhttp_clear_headers(¶ms_q);
739 : 0 : }
740 [ # # ]: 0 : evhttp_uri_free(uri_parsed);
741 : :
742 : 0 : return result;
743 [ # # ]: 0 : }
744 : :
745 : 0 : void RegisterHTTPHandler(const std::string &prefix, bool exactMatch, const HTTPRequestHandler &handler)
746 : : {
747 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Registering HTTP handler for %s (exactmatch %d)\n", prefix, exactMatch);
[ # # ][ # # ]
748 : 0 : LOCK(g_httppathhandlers_mutex);
749 [ # # ]: 0 : pathHandlers.emplace_back(prefix, exactMatch, handler);
750 : 0 : }
751 : :
752 : 0 : void UnregisterHTTPHandler(const std::string &prefix, bool exactMatch)
753 : : {
754 : 0 : LOCK(g_httppathhandlers_mutex);
755 : 0 : std::vector<HTTPPathHandler>::iterator i = pathHandlers.begin();
756 : 0 : std::vector<HTTPPathHandler>::iterator iend = pathHandlers.end();
757 [ # # ]: 0 : for (; i != iend; ++i)
758 [ # # ][ # # ]: 0 : if (i->prefix == prefix && i->exactMatch == exactMatch)
759 : 0 : break;
760 [ # # ]: 0 : if (i != iend)
761 : : {
762 [ # # ][ # # ]: 0 : LogPrint(BCLog::HTTP, "Unregistering HTTP handler for %s (exactmatch %d)\n", prefix, exactMatch);
[ # # ][ # # ]
[ # # ]
763 [ # # ]: 0 : pathHandlers.erase(i);
764 : 0 : }
765 : 0 : }
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