libassuan socket emulation file support

.gitignore

@@ -37,3 +37,5 @@ ssh-agent-adapter.VC.db
 int
 bin
 .vs
+*.vcxproj.user
+.vscode

common.c

@@ -9,6 +9,7 @@ static void con_activity_done(connection* con) {
 		CloseHandle(con->np2uds_th);
 		CloseHandle(con->uds2np_th);
 		free(con);
+		log("connection closed");
 	}
 }
 
@@ -33,25 +34,33 @@ DWORD WINAPI uds2np_thread(LPVOID param) {
 		ZeroMemory(&ol, sizeof(OVERLAPPED));
 		// read from pipe
 		if (!ReadFileEx(con->pipe, buf, BUFSIZE, &ol, apc_callback)) {
+			log("couldn't start read from pipe");
 			goto done;
 		}
 
 		SleepEx(INFINITE, TRUE);
 		bytes_read = 0;
-		if (con->abort_io || !GetOverlappedResult(con->pipe, &ol, &bytes_read, FALSE))
+		if (con->abort_io || !GetOverlappedResult(con->pipe, &ol, &bytes_read, FALSE)) {
+			log("couldn't get bytes from pipe, or read aborted");
 			goto done;
+		}
+		log("read %d bytes from pipe", bytes_read);
 
 		//now write to sock
 		bytes_written = 0;
 		while (bytes_written < bytes_read) {
 			int written = send(con->sock, buf + bytes_written, bytes_read - bytes_written, 0);
-			if (written == SOCKET_ERROR)
+			if (written == SOCKET_ERROR) {
+				log("error when writing to socket");
 				goto done;
+			}
 			bytes_written += written;
+			log("wrote %d (%d) of %d bytes to socket", written, bytes_written, bytes_read);
 		}
 	}
 
 done:
+	log("shutting down socket");
 	shutdown(con->sock, SD_SEND);
 	con_activity_done(con);
 	return 0;
@@ -68,21 +77,30 @@ DWORD WINAPI np2uds_thread(LPVOID param) {
 	while (1) {
 		// read from sock
 		bytes_read = recv(con->sock, buf, BUFSIZE, 0);
-		if (bytes_read <= 0)
+		if (bytes_read <= 0) {
+			log("nothing to read from socket");
 			goto done;
+		}
+		log("read %d bytes from socket", bytes_read);
 
 		// now write to pipe
 		bytes_written = 0;
 		ZeroMemory(&ol, sizeof(OVERLAPPED));
-		if (!WriteFileEx(con->pipe, buf, bytes_read, &ol, apc_callback))
+		if (!WriteFileEx(con->pipe, buf, bytes_read, &ol, apc_callback)) {
+			log("can't start write to pipe");
 			goto done;
-
+		}
+
 		SleepEx(INFINITE, TRUE);
-		if (!GetOverlappedResult(con->pipe, &ol, &bytes_written, FALSE))
+		if (!GetOverlappedResult(con->pipe, &ol, &bytes_written, FALSE)) {
+			log("couldn't write to pipe");
 			goto done;
+		}
+		log("wrote %d of %d bytes to pipe", bytes_written, bytes_read);
 	}
 
 done:
+	log("shutting down pipe");
 	QueueUserAPC(apc_abortio, con->uds2np_th, (ULONG_PTR)con);
 	con_activity_done(con);
 	return 0;

common.h

@@ -13,7 +13,7 @@
 #define DEFAULT_BUFLEN 512
 
 extern int debug_mode;
-#define log(...) {if (debug_mode) { printf(__VA_ARGS__); printf("\n");} } 
+#define log(...) {if (debug_mode!=0) { printf(__VA_ARGS__); printf("\n");} } 
 
 typedef struct _connection {
 	HANDLE pipe;

uds-2-np.c

@@ -1,12 +1,68 @@
+#include <assert.h>
 #include "common.h"
 
+#define LIBASSUAN_COOKIE_LEN 16
+
 int uds_agent_port = 47010;
 char* cookie = NULL;
 int cookie_len = 0;
 
+errno_t process_sock_file(wchar_t* filename) {
+	#define SHORT_BUFLEN 64
+
+	errno_t err;
+	FILE* sock_file;
+	size_t read_count, i, clen = 0;
+	char buf[SHORT_BUFLEN], *new_cookie = NULL;
+	int port;
+
+	err = _wfopen_s(&sock_file, filename, L"rb");
+	if (err != 0) {
+		return err;
+	}
+	read_count = fread_s(buf, SHORT_BUFLEN, sizeof(char), SHORT_BUFLEN/sizeof(char), sock_file);
+	fclose(sock_file);
+
+	port = atoi(buf);
+	if (port < 1 || port > 65535) {
+		err = errno;
+		return (err != 0) ? err : EINVAL;
+	}
+	uds_agent_port = (UINT)port;
+	log("gpg-agent is listening on port %d", uds_agent_port);
+
+	for (i = read_count; i && buf[i] != '\n'; i--, clen++) {
+		// loop until we hit newline character
+	}
+	i++; clen--; // cookie starts at buf[i] and goes for clen characters
+	log("cookie starts at charpos %d, length %d", i, read_count - i);
+	assert(clen == LIBASSUAN_COOKIE_LEN && read_count - i == LIBASSUAN_COOKIE_LEN);
+
+	new_cookie = malloc(clen);
+	if (new_cookie == NULL) {
+		return errno;
+	}
+	err = memcpy_s(new_cookie, clen, &buf[i], clen);
+	if (err != 0) {
+		free(new_cookie); new_cookie = NULL;
+		return errno;
+	}
+	assert(new_cookie[clen - 1] == buf[read_count - 1]);
+
+	if (cookie != NULL) {
+		free(cookie); cookie = NULL;
+	}
+	cookie = new_cookie;
+	cookie_len = clen;
+	return 0;
+
+	#undef SHORT_BUFLEN
+}
+
 void process_pipe_connection(connection* con) {
 	WSADATA wsaData;
 	struct sockaddr_in serv_addr;
+	int sc, err;
 
 	WSAStartup(MAKEWORD(2, 2), &wsaData);
 	con->sock = socket(AF_INET, SOCK_STREAM, 0);
@@ -17,7 +73,18 @@ void process_pipe_connection(connection* con) {
 
 	connect(con->sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
 
-	//TODO - write cookie
+	// write cookie
+	sc = send(con->sock, cookie, (int)cookie_len, 0);
+	if (sc == SOCKET_ERROR) {
+		err = WSAGetLastError();
+		printf("Cookie send failed: %d\n", err);
+		exit(1);
+	}
+	else if (sc != (int)cookie_len) {
+		printf("Cookie is %d bytes but %d bytes sent!\n", cookie_len, sc);
+		exit(1);
+	}
+	log("sent cookie to socket (length=%d)", sc);
 
 	//start threads
 	con->activity_count = 2;
@@ -27,24 +94,28 @@ void process_pipe_connection(connection* con) {
 
 int wmain(int argc, wchar_t *argv[], wchar_t *envp[])
 {
-	wchar_t pipe_name[MAX_PATH];
+	#define MINIBUFLEN 16
+
+	wchar_t pipe_name[MAX_PATH], sock_name[MAX_PATH], errstr[MINIBUFLEN];
+	size_t sock_name_len;
+	errno_t err;
 	OVERLAPPED ol;
 	DWORD client_pid;
 
 	//spawn a child and give back control to cmd
 	if (argc == 1) {
 		wchar_t cmdline[MAX_PATH];
-		STARTUPINFOW si;
+		STARTUPINFOW si;
 		PROCESS_INFORMATION pi;
 
 		cmdline[0] = L'\0';
 		wcscat(cmdline, argv[0]);
 		wcscat(cmdline, L" -z");
-		ZeroMemory(&si, sizeof(si));
-		si.cb = sizeof(STARTUPINFOW);
+		ZeroMemory(&si, sizeof(si));
+		si.cb = sizeof(STARTUPINFOW);
 		ZeroMemory(&pi, sizeof(pi));
 		CreateProcessW(NULL, cmdline, NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi);
-		swprintf_s(pipe_name, MAX_PATH, L"SSH_AUTH_SOCK=\\\\.\\pipe\\usd-2-np-%d", pi.dwProcessId);
+		swprintf_s(pipe_name, MAX_PATH, L"SSH_AUTH_SOCK=\\\\.\\pipe\\uds-2-np-%d", pi.dwProcessId);
 		_wputenv(pipe_name);
 		printf("set %ls", pipe_name);
 		return 0;
@@ -74,35 +145,43 @@ int wmain(int argc, wchar_t *argv[], wchar_t *envp[])
 		}
 	}
 
+	if ((err =_wgetenv_s(&sock_name_len, &sock_name, MAX_PATH, L"SSH_AUTH_SOCK")) != 0 || sock_name[0] == 0) {
+		printf("couldn't get original socket path\n");
+		exit(err);
+	}
+	if ((err = process_sock_file(&sock_name)) != 0) {
+		_wcserror_s(errstr, MINIBUFLEN, err);
+		printf("couldn't access socket %ls: %ls\n", sock_name, errstr);
+		exit(err);
+	}
 
-	//TODO - parse contents of file pointed by SSH_AUTH_SOCK env variable
-	// and read port and cookie info
-
-	swprintf_s(pipe_name, MAX_PATH, L"\\\\.\\pipe\\usd-2-np-%d", GetCurrentProcessId());
+	swprintf_s(pipe_name, MAX_PATH, L"\\\\.\\pipe\\uds-2-np-%d", GetCurrentProcessId());
 	ZeroMemory(&ol, sizeof(ol));
 	ol.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
-	log("incomig connections to pipe: %ls", pipe_name);
+	log("incoming connections to pipe: %ls", pipe_name);
 	log("will be routed to 127.0.0.1:%d", uds_agent_port);
-	while (1) {
-		connection *con = (connection*)malloc(sizeof(connection));
-		ZeroMemory(con, sizeof(connection));
-		con->pipe = CreateNamedPipeW(
-			pipe_name,		  // pipe name 
-			PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,       // read/write access 
-			PIPE_TYPE_BYTE |       // message type pipe 
-			PIPE_READMODE_BYTE |   // message-read mode 
-			PIPE_WAIT,                // blocking mode 
-			PIPE_UNLIMITED_INSTANCES, // max. instances  
-			BUFSIZE,                  // output buffer size 
-			BUFSIZE,                  // input buffer size 
-			0,                        // client time-out 
+	while (1) {
+		connection *con = (connection*)malloc(sizeof(connection));
+		ZeroMemory(con, sizeof(connection));
+		con->pipe = CreateNamedPipeW(
+			pipe_name,		  // pipe name 
+			PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,       // read/write access 
+			PIPE_TYPE_BYTE |       // message type pipe 
+			PIPE_READMODE_BYTE |   // message-read mode 
+			PIPE_WAIT,                // blocking mode 
+			PIPE_UNLIMITED_INSTANCES, // max. instances  
+			BUFSIZE,                  // output buffer size 
+			BUFSIZE,                  // input buffer size 
+			0,                        // client time-out 
 			NULL);
 
 		ConnectNamedPipe(con->pipe, &ol);
 		WaitForSingleObject(ol.hEvent, INFINITE);
 		GetNamedPipeClientProcessId(con->pipe, &client_pid);
 		log("connection accepted from pid:%d", client_pid);
 		process_pipe_connection(con);
+
+		#undef MINIBUFLEN
 	}
 
     return 0;