fix: Ws2_32_LoopRecv: handle recv() == 0; handle conf and hosts with BOM

shunf4 · Apr 27, 2020 · 4f0a1be · 4f0a1be
1 parent 9edc0d5
commit 4f0a1be
Show file tree

Hide file tree

Showing 5 changed files with 57 additions and 14 deletions.
diff --git a/README.md b/README.md
@@ -140,13 +140,18 @@ See [DevNotes](DEVNOTES.md).
 
 # To-do and Known Issues
 
-- [ ] Correctly handle conf and hosts that start with BOM
 - [ ] Add an option to totally prevent "DNS leak" ? (Do name lookup on
 SOCKS5 server only)
 - [ ] Properly handle "fork-and-exit" child process ? (In this case the
 descendant processes' dns queries would never succeed)
 - [ ] Remote DNS resolving based on UDP associate
 - [ ] Hook `sendto()`, coping with applications which do TCP fast open
+- [x] Connection closure should be correctly handled in
+      `Ws2_32_LoopRecv` and `Ws2_32_LoopSend` (fixed in 0.6.5)
+- [x] A large part of socks5 server name possibly lost when parsing
+      configuration (fixed in 0.6.5)
+- [x] Correctly handle conf and hosts that start with BOM (fixed in
+      0.6.5)
 - [X] Detect .NET CLR programs that is AnyCPU&prefers 32-bit/targeted x86
       /targeted x64. (These are "shimatta" programs, which must be
       injected by `CreateRemoteThread()`) (fixed in 0.6.2)

diff --git a/include/version.h b/include/version.h
@@ -23,5 +23,5 @@
 #define PXCH_VERSION_MINOR 6
 #endif
 #ifndef PXCH_VERSION_PATCH
-#define PXCH_VERSION_PATCH 4
+#define PXCH_VERSION_PATCH 5
 #endif
diff --git a/src/dll/hook_connect_win32.c b/src/dll/hook_connect_win32.c
@@ -446,6 +446,7 @@ int Ws2_32_LoopSend(void* pTempData, PXCH_UINT_PTR s, const char* SendBuf, int i
 
 		iReturn = send(s, pSendBuf, iRemaining, 0);
 		if (iReturn == SOCKET_ERROR) goto err_send;
+		if (iReturn == 0) goto err_send_zerobytes;
 		if (iReturn < iLength) {
 			FUNCIPCLOGD(L"send() only sent %d/%d bytes", iReturn, iLength);
 		}
@@ -462,6 +463,10 @@ int Ws2_32_LoopSend(void* pTempData, PXCH_UINT_PTR s, const char* SendBuf, int i
 	WSASetLastError(NO_ERROR);
 	return 0;
 
+err_send_zerobytes:
+	FUNCIPCLOGW(L"send() sends zero bytes!");
+	goto err_return;
+
 err_send_unexpected:
 	FUNCIPCLOGW(L"send() occurs unexpected error!");
 	goto err_return;
@@ -513,6 +518,7 @@ int Ws2_32_LoopRecv(void* pTempData, PXCH_UINT_PTR s, char* RecvBuf, int iLength
 
 		iReturn = recv(s, pRecvBuf, iRemaining, 0);
 		if (iReturn == SOCKET_ERROR) goto err_recv;
+		if (iReturn == 0) goto err_recv_closed;
 		if (iReturn < iLength) {
 			FUNCIPCLOGD(L"recv() only received %d/%d bytes", iReturn, iLength);
 		}
@@ -529,6 +535,10 @@ int Ws2_32_LoopRecv(void* pTempData, PXCH_UINT_PTR s, char* RecvBuf, int iLength
 	WSASetLastError(NO_ERROR);
 	return 0;
 
+err_recv_closed:
+	FUNCIPCLOGW(L"recv() receives zero bytes, connection closed!");
+	goto err_return;
+
 err_recv_unexpected:
 	FUNCIPCLOGW(L"recv() occurs unexpected error!");
 	goto err_return;

diff --git a/src/exe/args_and_config.c b/src/exe/args_and_config.c
@@ -232,6 +232,7 @@ static int OptionGetIpPortValue(PXCH_IP_PORT* pIpPort, PXCH_UINT32* pdwPrefixLen
 	WCHAR* pStartPrefix;
 	WCHAR* pAfterPrefix;
 	WCHAR cSaved;
+	int iResult;
 
 	pAfterIpPort = ConsumeStringInSet(pStart, pEndOptional, PXCH_CONFIG_PARSE_IP_PORT);
 
@@ -242,14 +243,14 @@ static int OptionGetIpPortValue(PXCH_IP_PORT* pIpPort, PXCH_UINT32* pdwPrefixLen
 
 	cSaved = *pAfterIpPort;
 	*pAfterIpPort = L'\0';
-
 	ZeroMemory(pIpPort, sizeof(PXCH_IP_PORT));
-	if (StringToAddress(pStart, (LPSOCKADDR)pIpPort, sizeof(PXCH_IP_PORT))) {
+	iResult = StringToAddress(pStart, (LPSOCKADDR)pIpPort, sizeof(PXCH_IP_PORT));
+	*pAfterIpPort = cSaved;
+	if (iResult) {
 		pszParseErrorMessage = L"Invalid IP address";
 		return -1;
 	}
 
-	*pAfterIpPort = cSaved;
 	if (*pAfterIpPort == L'/') {
 		PXCH_IP_PORT PrefixIpPort;
 		long lPrefix = -1;
@@ -271,12 +272,13 @@ static int OptionGetIpPortValue(PXCH_IP_PORT* pIpPort, PXCH_UINT32* pdwPrefixLen
 			return -1;
 		}
 
-		cSaved = *pAfterPrefix;
-		*pAfterPrefix = L'\0';
-
-		ZeroMemory(&PrefixIpPort, sizeof(PXCH_IP_PORT));
 		if (OptionGetNumberValue(&lPrefix, pStartPrefix, pAfterPrefix, 0, 128, FALSE)) {
-			if (StringToAddress(pStartPrefix, (LPSOCKADDR)&PrefixIpPort, sizeof(PXCH_IP_PORT))) {
+			cSaved = *pAfterPrefix;
+			*pAfterPrefix = L'\0';
+			ZeroMemory(&PrefixIpPort, sizeof(PXCH_IP_PORT));
+			iResult = StringToAddress(pStartPrefix, (LPSOCKADDR)&PrefixIpPort, sizeof(PXCH_IP_PORT));
+			*pAfterPrefix = cSaved;
+			if (iResult) {
 				pszParseErrorMessage = L"Invalid CIDR prefix";
 				return -1;
 			} else {
@@ -310,13 +312,12 @@ static int OptionGetIpPortValue(PXCH_IP_PORT* pIpPort, PXCH_UINT32* pdwPrefixLen
 				}
 			}
 		} else {
-			if (PrefixIpPort.CommonHeader.wTag == PXCH_HOST_TYPE_IPV4 && lPrefix > 32) {
+			if (pIpPort->CommonHeader.wTag == PXCH_HOST_TYPE_IPV4 && lPrefix > 32) {
 				pszParseErrorMessage = L"Prefix length exceeds 32 for an IPv4 address";
 				return -1;
 			}
 		}
 
-		*pAfterPrefix = cSaved;
 		*pdwPrefixLength = (PXCH_UINT32)lPrefix;
 	} else {
 		pAfterPrefix = pAfterIpPort;

diff --git a/src/stdlib_config_reader.c b/src/stdlib_config_reader.c
@@ -58,6 +58,7 @@ PXCH_UINT32 OpenConfigurationFile(PROXYCHAINS_CONFIG* pPxchConfig)
 	int i;
 	int iReturn;
 	DWORD dwLastError;
+	wint_t chFirst;
 
 	CloseConfigurationFile();
 
@@ -110,13 +111,18 @@ PXCH_UINT32 OpenConfigurationFile(PROXYCHAINS_CONFIG* pPxchConfig)
 
 validate_config_path:
 	for (i = 0; i < _countof(szConfigPathOptions) && szConfigPathOptions[i]; i++) {
-		if ((fPxchConfig = fopen(szConfigPathOptions[i], "r")) != NULL) {
+		if ((fPxchConfig = fopen(szConfigPathOptions[i], "r,ccs=UTF-8")) != NULL) {
 			break;
 		}
 	}
 
 	if (!fPxchConfig) goto err_not_found;
 
+	chFirst = fgetwc(fPxchConfig);
+	if (chFirst != WEOF && chFirst != 0xFEFF /* Unicode/UTF-16 BOM */) {
+		ungetwc(chFirst, fPxchConfig);
+	}
+
 	StringCchPrintfW(pPxchConfig->szConfigPath, _countof(pPxchConfig->szConfigPath), L"%S", szConfigPathOptions[i]);
 	LOGI(L"Configuration file: %ls", pPxchConfig->szConfigPath);
 	ullConfigurationLineNum = 0;
@@ -139,12 +145,18 @@ PXCH_UINT32 OpenConfigurationFile(PROXYCHAINS_CONFIG* pPxchConfig)
 PXCH_UINT32 OpenHostsFile(const WCHAR* szHostsFilePath)
 {
 	char szHostsFilePathNarrow[MAX_PATH * 2];
+	wint_t chFirst;
 
 	if (FAILED(StringCchPrintfA(szHostsFilePathNarrow, _countof(szHostsFilePathNarrow), "%ls", szHostsFilePath))) goto err_bufovf;
 
 	CloseHostsFile();
 
-	if ((fHosts = fopen(szHostsFilePathNarrow, "r")) == NULL) goto err_not_found;
+	// ccs=UTF-8 seems only work under Windows. Under cygwin, everything is assumed to be UTF-8
+	if ((fHosts = fopen(szHostsFilePathNarrow, "r,ccs=UTF-8")) == NULL) goto err_not_found;
+	chFirst = fgetwc(fHosts);
+	if (chFirst != WEOF && chFirst != 0xFEFF /* Unicode/UTF-16 BOM */) {
+		ungetwc(chFirst, fHosts);
+	}
 	return NO_ERROR;
 
 err_not_found:
@@ -203,6 +215,7 @@ PXCH_UINT32 HostsFileReadLine(unsigned long long* pullHostsLineNum, wchar_t* chB
 
 	ullHostsLineNum++;
 	*pullHostsLineNum = ullHostsLineNum;
+
 	pBuf = fgetws(chBuf, (int)cbBufSize, fHosts);
 
 	if (pBuf == NULL) {
@@ -254,7 +267,14 @@ long ConfigurationTellPos()
 
 void ConfigurationRewind()
 {
+	wint_t chFirst;
+
 	rewind(fPxchConfig);
+
+	chFirst = fgetwc(fPxchConfig);
+	if (chFirst != WEOF && chFirst != 0xFEFF /* Unicode/UTF-16 BOM */) {
+		ungetwc(chFirst, fPxchConfig);
+	}
 	ullConfigurationLineNum = 0;
 }
 
@@ -265,6 +285,13 @@ long HostsTellPos()
 
 void HostsRewind()
 {
+	wint_t chFirst;
+
 	rewind(fHosts);
+
+	chFirst = fgetwc(fHosts);
+	if (chFirst != WEOF && chFirst != 0xFEFF /* Unicode/UTF-16 BOM */) {
+		ungetwc(chFirst, fHosts);
+	}
 	ullHostsLineNum = 0;
 }