net: Use steady clock in InterruptibleRecv

Author: MarcoFalke

src/netbase.cpp

@@ -36,8 +36,8 @@ static Proxy nameProxy GUARDED_BY(g_proxyinfo_mutex);
 int nConnectTimeout = DEFAULT_CONNECT_TIMEOUT;
 bool fNameLookup = DEFAULT_NAME_LOOKUP;
 
-// Need ample time for negotiation for very slow proxies such as Tor (milliseconds)
-int g_socks5_recv_timeout = 20 * 1000;
+// Need ample time for negotiation for very slow proxies such as Tor
+std::chrono::milliseconds g_socks5_recv_timeout = 20s;
 static std::atomic<bool> interruptSocks5Recv(false);
 
 std::vector<CNetAddr> WrappedGetAddrInfo(const std::string& name, bool allow_lookup)
@@ -296,7 +296,7 @@ enum class IntrRecvError {
  *
  * @param data The buffer where the read bytes should be stored.
  * @param len The number of bytes to read into the specified buffer.
- * @param timeout The total timeout in milliseconds for this read.
+ * @param timeout The total timeout for this read.
  * @param sock The socket (has to be in non-blocking mode) from which to read bytes.
  *
  * @returns An IntrRecvError indicating the resulting status of this read.
@@ -306,10 +306,10 @@ enum class IntrRecvError {
  * @see This function can be interrupted by calling InterruptSocks5(bool).
  *      Sockets can be made non-blocking with Sock::SetNonBlocking().
  */
-static IntrRecvError InterruptibleRecv(uint8_t* data, size_t len, int timeout, const Sock& sock)
+static IntrRecvError InterruptibleRecv(uint8_t* data, size_t len, std::chrono::milliseconds timeout, const Sock& sock)
 {
-    int64_t curTime = GetTimeMillis();
-    int64_t endTime = curTime + timeout;
+    auto curTime{Now<SteadyMilliseconds>()};
+    const auto endTime{curTime + timeout};
     while (len > 0 && curTime < endTime) {
         ssize_t ret = sock.Recv(data, len, 0); // Optimistically try the recv first
         if (ret > 0) {
@@ -333,7 +333,7 @@ static IntrRecvError InterruptibleRecv(uint8_t* data, size_t len, int timeout, c
         }
         if (interruptSocks5Recv)
             return IntrRecvError::Interrupted;
-        curTime = GetTimeMillis();
+        curTime = Now<SteadyMilliseconds>();
     }
     return len == 0 ? IntrRecvError::OK : IntrRecvError::Timeout;
 }

src/test/fuzz/socks5.cpp

@@ -14,12 +14,12 @@
 #include <string>
 #include <vector>
 
+extern std::chrono::milliseconds g_socks5_recv_timeout;
+
 namespace {
-int default_socks5_recv_timeout;
+decltype(g_socks5_recv_timeout) default_socks5_recv_timeout;
 };
 
-extern int g_socks5_recv_timeout;
-
 void initialize_socks5()
 {
     static const auto testing_setup = MakeNoLogFileContext<const BasicTestingSetup>();
@@ -35,7 +35,7 @@ FUZZ_TARGET_INIT(socks5, initialize_socks5)
     InterruptSocks5(fuzzed_data_provider.ConsumeBool());
     // Set FUZZED_SOCKET_FAKE_LATENCY=1 to exercise recv timeout code paths. This
     // will slow down fuzzing.
-    g_socks5_recv_timeout = (fuzzed_data_provider.ConsumeBool() && std::getenv("FUZZED_SOCKET_FAKE_LATENCY") != nullptr) ? 1 : default_socks5_recv_timeout;
+    g_socks5_recv_timeout = (fuzzed_data_provider.ConsumeBool() && std::getenv("FUZZED_SOCKET_FAKE_LATENCY") != nullptr) ? 1ms : default_socks5_recv_timeout;
     FuzzedSock fuzzed_sock = ConsumeSock(fuzzed_data_provider);
     // This Socks5(...) fuzzing harness would have caught CVE-2017-18350 within
     // a few seconds of fuzzing.