hvpty: wrap WinSock functions in HyperVSocket class (#11)

hvpty/GetVmId.cpp

@@ -122,13 +122,8 @@ HRESULT GetVmId(
     const std::wstring &DistroName,
     int *WslVersion)
 {
-    int bRes;
     HRESULT hRes;
 
-    WSADATA wsaData;
-    bRes = WSAStartup(MAKEWORD(2, 2), &wsaData);
-    assert(bRes == 0);
-
     hRes = CoInitializeEx(nullptr, COINIT_MULTITHREADED);
     assert(hRes == 0);
 
@@ -197,6 +192,5 @@ HRESULT GetVmId(
     if (wslSession)
         wslSession->Release();
     CoUninitialize();
-    WSACleanup();
     return hRes;
 }

hvpty/HyperVSocket.cpp

@@ -0,0 +1,144 @@
+/* 
+ * This file is part of wslbridge2 project
+ * Licensed under the GNU General Public License version 3
+ * Copyright (C) 2019 Biswapriyo Nath
+ */
+
+#include <winsock.h>
+#include <assert.h>
+
+#include "../hvsocket/hvsocket.h"
+#include "HyperVSocket.hpp"
+
+/* The range 49152–65535 contains dynamic ports */
+#define DYNAMIC_PORT_LOW 49152
+#define DYNAMIC_PORT_HIGH 65535
+#define BIND_MAX_RETRIES 10
+
+#define RANDOMPORT() \
+rand() % (DYNAMIC_PORT_HIGH - DYNAMIC_PORT_LOW) + DYNAMIC_PORT_LOW
+
+HyperVSocket::HyperVSocket(void)
+{
+    m_hModule = LoadLibraryExW(
+                L"ws2_32.dll",
+                nullptr,
+                LOAD_LIBRARY_SEARCH_SYSTEM32);
+    assert(m_hModule != nullptr);
+
+    pfnAccept = (ACCEPTPROC)GetProcAddress(m_hModule, "accept");
+    pfnBind = (BINDPROC)GetProcAddress(m_hModule, "bind");
+    pfnCloseSocket = (CLOSESOCKETPROC)GetProcAddress(m_hModule, "closesocket");
+    pfnConnect = (CONNETCPROC)GetProcAddress(m_hModule, "connect");
+    pfnListen = (LISTENPROC)GetProcAddress(m_hModule, "listen");
+    pfnRecv = (RECVPROC)GetProcAddress(m_hModule, "recv");
+    pfnSend = (SENDPROC)GetProcAddress(m_hModule, "send");
+    pfnSocket = (SOCKETPROC)GetProcAddress(m_hModule, "socket");
+    pfnSetSockOpt = (SETSOCKOPTPROC)GetProcAddress(m_hModule, "setsockopt");
+    pfnWSAStartup = (WSASTARTUPPROC)GetProcAddress(m_hModule, "WSAStartup");
+    pfnWSACleanup = (WSACLEANUPPROC)GetProcAddress(m_hModule, "WSACleanup");
+
+    struct WSAData wdata;
+    const int wsaRet = pfnWSAStartup(MAKEWORD(2,2), &wdata);
+    assert(wsaRet == 0);
+}
+
+HyperVSocket::~HyperVSocket(void)
+{
+    if (m_hModule)
+        FreeLibrary(m_hModule);
+    pfnWSACleanup();
+}
+
+SOCKET HyperVSocket::Create(void)
+{
+    const SOCKET sock = pfnSocket(
+                        AF_HYPERV,
+                        SOCK_STREAM,
+                        HV_PROTOCOL_RAW);
+    assert(sock > 0);
+
+    const int suspend = true;
+    const int suspendRet = pfnSetSockOpt(
+                           sock,
+                           HV_PROTOCOL_RAW,
+                           HVSOCKET_CONNECTED_SUSPEND,
+                           &suspend,
+                           sizeof suspend);
+    assert(suspendRet == 0);
+
+    /* Return socket to caller */
+    return sock;
+}
+
+SOCKET HyperVSocket::Accept(const SOCKET sock)
+{
+    const SOCKET cSock = pfnAccept(sock, nullptr, nullptr);
+    assert(cSock > 0);
+    return cSock;
+}
+
+void HyperVSocket::Connect(const SOCKET sock, const GUID *VmId, const int port)
+{
+    const int timeout = 10 * 1000; /* Ten seconds */
+    const int timeRet = pfnSetSockOpt(
+                        sock,
+                        HV_PROTOCOL_RAW,
+                        HVSOCKET_CONNECT_TIMEOUT,
+                        &timeout,
+                        sizeof timeout);
+    assert(timeRet == 0);
+
+    struct SOCKADDR_HV addr = {};
+    addr.Family = AF_HYPERV;
+    memcpy(&addr.VmId, VmId, sizeof addr.VmId);
+    memcpy(&addr.ServiceId, &HV_GUID_VSOCK_TEMPLATE, sizeof addr.ServiceId);
+    addr.ServiceId.Data1 = port;
+    const int connectRet = pfnConnect(sock, &addr, sizeof addr);
+    assert(connectRet == 0);
+}
+
+int HyperVSocket::Listen(const SOCKET sock, const GUID *VmId)
+{
+    struct SOCKADDR_HV addr = {};
+    addr.Family = AF_HYPERV;
+    memcpy(&addr.VmId, VmId, sizeof addr.VmId);
+    memcpy(&addr.ServiceId, &HV_GUID_VSOCK_TEMPLATE, sizeof addr.ServiceId);
+
+    /* Try to bind to a dynamic port */
+    int nretries = 0;
+    int port;
+
+    while (nretries < BIND_MAX_RETRIES)
+    {
+        port = RANDOMPORT();
+        addr.ServiceId.Data1 = port;
+        const int bindRet = pfnBind(sock, &addr, sizeof addr);
+        if (bindRet == 0)
+            break;
+
+        nretries++;
+    }
+
+    const int listenRet = pfnListen(sock, -1);
+    assert(listenRet == 0);
+
+    /* Return port number to caller */
+    return port;
+}
+
+int HyperVSocket::Receive(const SOCKET sock, void *buf, int len)
+{
+    return pfnRecv(sock, buf, len, 0);
+}
+
+int HyperVSocket::Send(const SOCKET sock, void *buf, int len)
+{
+    return pfnSend(sock, buf, len, 0);
+}
+
+void HyperVSocket::Close(const SOCKET sock)
+{
+    if (sock > 0)
+        pfnCloseSocket(sock);
+}

hvpty/HyperVSocket.hpp

@@ -0,0 +1,56 @@
+/* 
+ * This file is part of wslbridge2 project
+ * Licensed under the GNU General Public License version 3
+ * Copyright (C) 2019 Biswapriyo Nath
+ */
+
+#ifndef HYPERVSOCKET_HPP
+#define HYPERVSOCKET_HPP
+
+#ifndef SOCKET
+#define SOCKET size_t
+#endif
+
+/* Windows socket functions pointers from ws2_32.dll file */
+typedef SOCKET (WINAPI *ACCEPTPROC)(SOCKET, void*, int*);
+typedef int (WINAPI *BINDPROC)(SOCKET, const void*, int);
+typedef int (WINAPI *CLOSESOCKETPROC)(SOCKET);
+typedef int (WINAPI *CONNETCPROC)(SOCKET, const void*, int);
+typedef int (WINAPI *LISTENPROC)(SOCKET, int);
+typedef int (WINAPI *RECVPROC)(SOCKET, void*, int, int);
+typedef int (WINAPI *SENDPROC)(SOCKET, const void*, int, int);
+typedef SOCKET (WINAPI *SOCKETPROC)(int, int, int);
+typedef int (WINAPI *SETSOCKOPTPROC)(SOCKET, int, int, const void*, int);
+typedef int (WINAPI *WSASTARTUPPROC)(WORD, void*);
+typedef int (WINAPI *WSACLEANUPPROC)(void);
+
+/* This wraps WinSock functions to separate identical Cygwin imports */
+class HyperVSocket
+{
+public:
+    HyperVSocket(void);
+    ~HyperVSocket(void);
+    SOCKET Create(void);
+    SOCKET Accept(const SOCKET sock);
+    void Connect(const SOCKET sock, const GUID *VmId, const int port);
+    int Listen(const SOCKET sock, const GUID *VmId);
+    int Receive(const SOCKET sock, void *buf, int len);
+    int Send(const SOCKET sock, void *buf, int len);
+    void Close(const SOCKET sock);
+
+private:
+    HMODULE m_hModule;
+    ACCEPTPROC pfnAccept;
+    BINDPROC pfnBind;
+    CLOSESOCKETPROC pfnCloseSocket;
+    CONNETCPROC pfnConnect;
+    LISTENPROC pfnListen;
+    RECVPROC pfnRecv;
+    SENDPROC pfnSend;
+    SOCKETPROC pfnSocket;
+    SETSOCKOPTPROC pfnSetSockOpt;
+    WSASTARTUPPROC pfnWSAStartup;
+    WSACLEANUPPROC pfnWSACleanup;
+};
+
+#endif /* HYPERVSOCKET_HPP */

hvpty/Makefile.frontend

@@ -14,11 +14,12 @@ ifdef RELEASE
 LFLAGS += -static -static-libgcc -static-libstdc++
 endif
 
-LIBS = -liphlpapi -lole32 -lws2_32
+LIBS = -liphlpapi -lole32
 BINS = \
 $(BINDIR)/GetIp.obj \
 $(BINDIR)/GetVmId.obj \
 $(BINDIR)/Helpers.obj \
+$(BINDIR)/HyperVSocket.obj \
 $(BINDIR)/hvpty.obj \
 $(BINDIR)/SocketIo.obj \
 $(BINDIR)/TerminalState.obj
@@ -34,13 +35,16 @@ $(NAME) : $(BINS)
 
 $(BINDIR)/GetIp.obj : GetIp.cpp
 	$(CXX) -c $(CFLAGS) $< -o $@
-    
+
 $(BINDIR)/GetVmId.obj : GetVmId.cpp
 	$(CXX) -c $(CFLAGS) $< -o $@
 
 $(BINDIR)/Helpers.obj : ../wslbridge/Helpers.cpp
 	$(CXX) -c $(CFLAGS) $(CCOPT) $< -o $@
 
+$(BINDIR)/HyperVSocket.obj : HyperVSocket.cpp
+	$(CXX) -c $(CFLAGS) $(CCOPT) $< -o $@
+
 $(BINDIR)/hvpty.obj : hvpty.cpp
 	$(CXX) -c $(CFLAGS) $(CCOPT) $< -o $@