major rewrite, reverse mode works again.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@1520 ec53bebd-3082-4978-b11e-865c3cabbd6b

appl/kx/kx.c

@@ -100,13 +100,14 @@ usr2handler (int sig)
 
 static int
 connect_host (char *host, char *user, des_cblock *key,
-	      des_key_schedule schedule, int passivep, int port)
+	      des_key_schedule schedule, int port,
+	      struct sockaddr_in *thisaddr,
+	      struct sockaddr_in *thataddr)
 {
      CREDENTIALS cred;
      KTEXT_ST text;
      MSG_DAT msg;
      int status;
-     struct sockaddr_in thisaddr, thataddr;
      int addrlen;
      struct hostent *hostent;
      int s;
@@ -116,39 +117,28 @@ connect_host (char *host, char *user, des_cblock *key,
 
      hostent = gethostbyname (host);
      if (hostent == NULL) {
-	  fprintf (stderr,
+	 warnx ("%s: gethostbyname '%s' failed: %s", prog, host,
-		   "%s: gethostbyname '%s' failed: %s\n", prog, host,
 #ifdef HAVE_H_ERRNO
-		   hstrerror(h_errno));
+		hstrerror(h_errno)
 #else
-		   "unknown error");
+		"unknown error"
 #endif
-	  return -1;
+	     );
+	 return -1;
      }
 
-     memset (&thataddr, 0, sizeof(thataddr));
+     memset (thataddr, 0, sizeof(*thataddr));
-     thataddr.sin_family = AF_INET;
+     thataddr->sin_family = AF_INET;
-     thataddr.sin_port   = port;
+     thataddr->sin_port   = port;
      for(p = hostent->h_addr_list; *p; ++p) {
-	 int one = 1;
+	 memcpy (&thataddr->sin_addr, *p, sizeof(thataddr->sin_addr));
-
-	 memcpy (&thataddr.sin_addr, *p, sizeof(thataddr.sin_addr));
 
 	 s = socket (AF_INET, SOCK_STREAM, 0);
-	 if (s < 0) {
+	 if (s < 0)
-	     fprintf (stderr, "%s: socket failed: %s\n",
+	     err (1, "%s: socket failed", prog);
-		      prog,
-		      strerror(errno));
-	     return -1;
-	 }
 
-#if defined(TCP_NODELAY) && defined(HAVE_SETSOCKOPT)
+	 if (connect (s, (struct sockaddr *)thataddr, sizeof(*thataddr)) < 0) {
-	 setsockopt (s, IPPROTO_TCP, TCP_NODELAY, (void *)&one, sizeof(one));
+	     warn ("%s: connect(%s) failed", prog, host);
-#endif
-
-	 if (connect (s, (struct sockaddr *)&thataddr, sizeof(thataddr)) < 0) {
-	     fprintf (stderr, "%s: connect(%s) failed: %s\n", prog, host,
-		      strerror(errno));
 	     close (s);
 	     continue;
 	 } else {
@@ -158,61 +148,20 @@ connect_host (char *host, char *user, des_cblock *key,
      if (*p == NULL)
 	 return -1;
 
-     addrlen = sizeof(thisaddr);
+     addrlen = sizeof(*thisaddr);
-     if (getsockname (s, (struct sockaddr *)&thisaddr, &addrlen) < 0 ||
+     if (getsockname (s, (struct sockaddr *)thisaddr, &addrlen) < 0 ||
-	 addrlen != sizeof(thisaddr)) {
+	 addrlen != sizeof(*thisaddr))
-	  fprintf (stderr, "%s: getsockname(%s) failed: %s\n",
+	 err(1, "%s: getsockname(%s) failed",
-		   prog, host, strerror(errno));
+	     prog, host);
-	  return -1;
-     }
      status = krb_sendauth (KOPT_DO_MUTUAL, s, &text, "rcmd",
 			    host, krb_realmofhost (host),
 			    getpid(), &msg, &cred, schedule,
-			    &thisaddr, &thataddr, KX_VERSION);
+			    thisaddr, thataddr, KX_VERSION);
      if (status != KSUCCESS) {
-	  fprintf (stderr, "%s: %s: %s\n", prog, host,
+	 warnx ("%s: %s: %s\n", prog, host, krb_get_err_text(status));
-		   krb_get_err_text(status));
+	 return -1;
-	  return -1;
      }
-
      memcpy(key, cred.session, sizeof(des_cblock));
-     strncpy (name, user, sizeof(name));
-     name[sizeof(name) - 1] = '\0';
-     if (krb_net_write (s, name, sizeof(name)) != sizeof(name)) {
-	  fprintf (stderr, "%s: write: %s\n", prog, strerror(errno));
-	  return -1;
-     }
-     if (krb_net_read (s, &b, sizeof(b)) != sizeof(b)) {
-	  fprintf (stderr, "%s: read: %s\n", prog,
-		   strerror(errno));
-	  return -1;
-     }
-     if (b) {
-	  char buf[BUFSIZ];
-
-	  krb_net_read (s, buf, sizeof(buf));
-	  buf[BUFSIZ - 1] = '\0';
-
-	  fprintf (stderr, "%s: %s: %s\n", prog, host, buf);
-	  return -1;
-     }
-     b = passivep;
-     if (krb_net_write (s, &b, sizeof(b)) != sizeof(b)) {
-	  fprintf (stderr, "%s: write: %s\n", prog, strerror(errno));
-	  return -1;
-     }
-
-     if (krb_net_read (s, display, display_size) != display_size) {
-	  fprintf (stderr, "%s: read: %s\n", prog, strerror(errno));
-	  return -1;
-     }
-     
-     if (krb_net_read (s, xauthfile, xauthfile_size) != xauthfile_size) {
-	  fprintf (stderr, "%s: read: %s\n", prog,
-		   strerror(errno));
-	  return -1;
-     }
-
      return s;
 }
 
@@ -222,76 +171,23 @@ connect_host (char *host, char *user, des_cblock *key,
  */
 
 static int
-start_session(int xserver, int fd, des_cblock *iv,
+passive_session (int xserver, int fd, des_cblock *iv,
-	      des_key_schedule schedule)
+		 des_key_schedule schedule)
 {
-     u_char beg[12];
+    if (replace_cookie (xserver, fd, XauFileName()))
-     int bigendianp;
+	return 1;
-     unsigned n, d, npad, dpad;
+    else
-     Xauth *auth;
+	return copy_encrypted (xserver, fd, iv, schedule);
-     FILE *f;
+}
-     char *filename;
-     u_char zeros[6] = {0, 0, 0, 0, 0, 0};
 
-     if (krb_net_read (fd, beg, sizeof(beg)) != sizeof(beg))
+static int
-	  return 1;
+active_session (int xserver, int fd, des_cblock *iv,
-     if (krb_net_write (xserver, beg, 6) != 6)
+		des_key_schedule schedule)
-	  return 1;
+{
-     bigendianp = beg[0] == 'B';
+    if (verify_and_remove_cookies (xserver, fd))
-     if (bigendianp) {
+	return 1;
-	  n = (beg[6] << 8) | beg[7];
+    else
-	  d = (beg[8] << 8) | beg[9];
+	return copy_encrypted (xserver, fd, iv, schedule);
-     } else {
-	  n = (beg[7] << 8) | beg[6];
-	  d = (beg[9] << 8) | beg[8];
-     }
-     if (n != 0 || d != 0)
-	  return 1;
-     filename = XauFileName();
-     if (filename == NULL)
-	  return 1;
-     f = fopen(filename, "r");
-     if (f) {
-	  u_char len[6] = {0, 0, 0, 0, 0, 0};
-
-	  auth = XauReadAuth(f);
-	  fclose(f);
-	  n = auth->name_length;
-	  d = auth->data_length;
-	  if (bigendianp) {
-	       len[0] = n >> 8;
-	       len[1] = n & 0xFF;
-	       len[2] = d >> 8;
-	       len[3] = d & 0xFF;
-	  } else {
-	       len[0] = n & 0xFF;
-	       len[1] = n >> 8;
-	       len[2] = d & 0xFF;
-	       len[3] = d >> 8;
-	  }
-	  if (krb_net_write (xserver, len, 6) != 6)
-	       return 1;
-	  if(krb_net_write (xserver, auth->name, n) != n)
-	       return 1;
-	  npad = (4 - (n % 4)) % 4;
-	  if (npad) { 
-	       if (krb_net_write (xserver, zeros, npad) != npad)
-		    return 1;
-	  }
-	  if (krb_net_write (xserver, auth->data, d) != d)
-	       return 1;
-	  dpad = (4 - (d % 4)) % 4;
-	  if (dpad) { 
-	       if (krb_net_write (xserver, zeros, dpad) != dpad)
-		    return 1;
-	  }
-	  XauDisposeAuth(auth);
-     } else {
-	  if(krb_net_write(xserver, zeros, 6) != 6)
-	       return 1;
-     }
-
-     return copy_encrypted (xserver, fd, iv, schedule);
 }
 
 static void
@@ -304,8 +200,7 @@ status_output (int debugp)
 	
 	pid = fork();
 	if (pid < 0) {
-	    fprintf (stderr, "%s: fork: %s\n", prog, strerror(errno));
+	    err(1, "%s: fork", prog);
-	    exit (1);
 	} else if (pid > 0) {
 	    printf ("%u\t%s\t%s\n", (unsigned)pid, display, xauthfile);
 	    exit (0);
@@ -316,158 +211,323 @@ status_output (int debugp)
 }
 
 /*
- *
+ * Obtain an authenticated connection to `host' on `port'.  Send a kx
+ * message saying we are `user' and want to use passive mode.  Wait
+ * for answer on that connection and fork of a child for every new
+ * connection we have to make.
  */
 
 static int
-doit_passive (char *host, char *user, int debugp, int port)
+doit_passive (char *host, char *user, int debugp, int keepalivep,
+	      int port)
 {
      des_key_schedule schedule;
      des_cblock key;
      int otherside;
+     struct sockaddr_in me, him;
+     u_char msg[1024], *p;
+     int len;
+     void *ret;
+     u_int32_t tmp;
 
-     otherside = connect_host (host, user, &key, schedule, 1, port);
+     otherside = connect_host (host, user, &key, schedule, port,
+			       &me, &him);
      if (otherside < 0)
 	 return 1;
+#if defined(SO_KEEPALIVE) && defined(HAVE_SETSOCKOPT)
+     if (keepalivep) {
+	 int one = 1;
+
+	 setsockopt (otherside, SOL_SOCKET, SO_KEEPALIVE, (void *)&one,
+		     sizeof(one));
+     }
+#endif
+
+     p = msg;
+     *p++ = INIT;
+     len = strlen(user);
+     p += krb_put_int (len, p, 4);
+     strncpy(p, user, len);
+     p += len;
+     *p++ = PASSIVE | (keepalivep ? KEEP_ALIVE : 0);
+     if (write_encrypted (otherside, msg, p - msg, schedule,
+			  &key, &me, &him) < 0)
+	 err (1, "%s: write to %s failed", prog, host);
+     len = read_encrypted (otherside, msg, sizeof(msg), &ret,
+			   schedule, &key, &him, &me);
+     if (len < 0)
+	 err (1, "%s: read from %s failed", prog, host);
+     p = (u_char *)ret;
+     if (*p == ERROR) {
+	 p++;
+	 p += krb_get_int (p, &tmp, 4, 0);
+	 errx (1, "%s: %s: %.*s", prog, host, tmp, p);
+     } else if (*p != ACK) {
+	 errx (1, "%s: %s: strange msg %d", prog, host, *p);
+     } else
+	 p++;
+     p += krb_get_int (p, &tmp, 4, 0);
+     strncpy(display, p, tmp);
+     display[tmp] = '\0';
+     p += tmp;
+
+     p += krb_get_int (p, &tmp, 4, 0);
+     strncpy(xauthfile, p, tmp);
+     xauthfile[tmp] = '\0';
+     p += tmp;
+
      status_output (debugp);
      for (;;) {
-	 char tmp[6];
 	 pid_t child;
 	 int i;
 
-	 i = krb_net_read (otherside, tmp, sizeof(tmp));
+	 len = read_encrypted (otherside, msg, sizeof(msg), &ret,
-	 if (i < 0) {
+			       schedule, &key, &him, &me);
-	     fprintf (stderr, "%s: read: %s\n", prog, strerror(errno));
+	 if (len < 0)
-	     return 1;
+	     err (1, "%s: read from %s failed", prog, host);
-	 } else if (i == 0)
+	 else if (len == 0)
 	     return 0;
+
+	 p = (u_char *)ret;
+	 if (*p == ERROR) {
+	     p++;
+	     p += krb_get_int (p, &tmp, 4, 0);
+	     errx (1, "%s: %s: %.*s", prog, host, tmp, p);
+	 } else if(*p != NEW_CONN) {
+	     errx (1, "%s: %s: strange msg %d", prog, host, *p);
+	 } else {
+	     p++;
+	     p += krb_get_int (p, &tmp, 4, 0);
+	 }
+	 
 	 ++nchild;
 	 child = fork ();
 	 if (child < 0) {
-	     fprintf (stderr, "%s: fork: %s\n", prog,
+	     warn("%s: fork", prog);
-		      strerror(errno));
 	     continue;
 	 } else if (child == 0) {
 	     struct sockaddr_in addr;
 	     int addrlen = sizeof(addr);
 	     int fd;
-	     int one = 1;
-	     int port;
 	     int xserver;
 
-	     if (getpeername (otherside, (struct sockaddr *)&addr,
+	     addr = him;
-			      &addrlen) < 0) {
-		 fprintf (stderr, "%s: getpeername: %s\n", prog,
-			  strerror(errno));
-		 exit (1);
-	     }
 	     close (otherside);
 
-	     sscanf (tmp, "%d", &port);
+	     addr.sin_port = htons(tmp);
-	     addr.sin_port = htons(port);
 	     fd = socket (AF_INET, SOCK_STREAM, 0);
-	     if (fd < 0) {
+	     if (fd < 0)
-		 fprintf (stderr, "%s: socket: %s\n", prog, strerror(errno));
+		 err(1, "%s: socket", prog);
-		 exit (1);
-	     }
 #if defined(TCP_NODELAY) && defined(HAVE_SETSOCKOPT)
-	     setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, (void *)&one,
+	     {
-			 sizeof(one));
+		 int one = 1;
-#endif
+
-	     if (connect (fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+		 setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, (void *)&one,
-		 fprintf (stderr, "%s: connect: %s\n", prog, strerror(errno));
+			     sizeof(one));
-		 exit (1);
 	     }
+#endif
+#if defined(SO_KEEPALIVE) && defined(HAVE_SETSOCKOPT)
+	     if (keepalivep) {
+		 int one = 1;
+
+		 setsockopt (fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&one,
+			     sizeof(one));
+	     }
+#endif
+
+	     if (connect (fd, (struct sockaddr *)&addr, sizeof(addr)) < 0)
+		 err(1, "%s: connect", prog);
 	     xserver = connect_local_xsocket (0);
 	     if (xserver < 0)
 		 return 1;
-	     return start_session (xserver, fd, &key, schedule);
+	     return passive_session (xserver, fd, &key, schedule);
 	 } else {
 	 }
      }
 }
 
 /*
- *
+ * Allocate a local pseudo-xserver and wait for connections 
  */
 
 static int
-doit_active (char *host, char *user, int debugpp, int tcpp, int port)
+doit_active (char *host, char *user,
+	     int debugpp, int keepalivep, int tcpp, int port)
 {
-     des_key_schedule schedule;
+    des_key_schedule schedule;
-     des_cblock key;
+    des_cblock key;
-     int rendez_vous1 = 0, rendez_vous2 = 0;
+    int otherside;
-     int tmp;
+    int rendez_vous1 = 0, rendez_vous2 = 0;
+    struct sockaddr_in me, him;
+    u_char msg[1024], *p;
+    int len = strlen(user);
+    void *ret;
+    u_int32_t tmp;
+    char *s;
 
-     tmp = get_xsockets (&rendez_vous1,
+    otherside = connect_host (host, user, &key, schedule, port,
-			 tcpp ? &rendez_vous2 : NULL);
+			      &me, &him);
-     if (tmp < 0)
+    if (otherside < 0)
-	 return 1;
+	return 1;
-     display_num = tmp;
+#if defined(SO_KEEPALIVE) && defined(HAVE_SETSOCKOPT)
-     strncpy(xauthfile, tempnam("/tmp", NULL), xauthfile_size);
+    if (keepalivep) {
-     if (create_and_write_cookie (xauthfile, cookie, cookie_len))
+	int one = 1;
-	 return 1;
-     status_output (debugpp);
-     for (;;) {
-	 fd_set fdset;
-	 pid_t child;
-	 int fd, thisfd;
-	 int zero = 0;
-	 int one = 1;
 
-	 FD_ZERO(&fdset);
+	setsockopt (otherside, SOL_SOCKET, SO_KEEPALIVE, (void *)&one,
-	 if (rendez_vous1)
+		    sizeof(one));
-	     FD_SET(rendez_vous1, &fdset);
+    }
-	 if (rendez_vous2)
-	     FD_SET(rendez_vous2, &fdset);
-	 if (select(FD_SETSIZE, &fdset, NULL, NULL, NULL) <= 0)
-	     continue;
-	 if (rendez_vous1 && FD_ISSET(rendez_vous1, &fdset))
-	     thisfd = rendez_vous1;
-	 else if (rendez_vous2 && FD_ISSET(rendez_vous2, &fdset))
-	     thisfd = rendez_vous2;
-	 else
-	     continue;
-
-	 fd = accept (thisfd, NULL, &zero);
-	 if (fd < 0)
-	     if (errno == EINTR)
-		 continue;
-	     else {
-		 fprintf (stderr, "%s: accept: %s\n", prog,
-			  strerror(errno));
-		 return 1;
-	     }
-#if defined(TCP_NODELAY) && defined(HAVE_SETSOCKOPT)
-	 setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, (void *)&one, sizeof(one));
 #endif
-	 ++nchild;
+    p = msg;
-	 child = fork ();
+    *p++ = INIT;
-	 if (child < 0) {
+    len = strlen(user);
-	     fprintf (stderr, "%s: fork: %s\n", prog,
+    p += krb_put_int (len, p, 4);
-		      strerror(errno));
+    strncpy(p, user, len);
-	     continue;
+    p += len;
-	 } else if (child == 0) {
+    *p++ = (keepalivep ? KEEP_ALIVE : 0);
-	     int kxd;
-	     u_char zero = 0;
 
-	     if (rendez_vous1)
+    s = getenv("DISPLAY");
-		 close (rendez_vous1);
+    if (s == NULL || (s = strchr(s, ':')) == NULL) 
-	     if (rendez_vous2)
+	s = ":0";
-		 close (rendez_vous2);
+    len = strlen (s);
-	     kxd = connect_host (host, user, &key, schedule, 0, port);
+    p += krb_put_int (len, p, 4);
-	     if (kxd < 0)
+    strncpy (p, s, len);
-		 return 1;
+    p += len;
-	     if (krb_net_write (kxd, &zero, sizeof(zero)) != sizeof(zero)) {
+
-		 fprintf (stderr, "%s: write: %s\n", prog,
+    s = getenv("XAUTHORITY");
-			  strerror(errno));
+    if (s == NULL)
-		 return 1;
+	s = "";
-	     }
+    len = strlen (s);
-	     return copy_encrypted (fd, kxd, &key, schedule);
+    p += krb_put_int (len, p, 4);
-	 } else {
+    strncpy (p, s, len);
-	     close (fd);
+    p += len;
-	 }
+
-     }
+    if (write_encrypted (otherside, msg, p - msg, schedule,
+			 &key, &me, &him) < 0)
+	err (1, "%s: write to %s failed", prog, host);
+
+    len = read_encrypted (otherside, msg, sizeof(msg), &ret,
+			  schedule, &key, &him, &me);
+    if (len < 0)
+	err (1, "%s: read from %s failed", prog, host);
+    p = (u_char *)ret;
+    if (*p == ERROR) {
+	p++;
+	p += krb_get_int (p, &tmp, 4, 0);
+	errx (1, "%s: %s: %.*s", prog, host, tmp, p);
+    } else if (*p != ACK) {
+	errx (1, "%s: %s: strange msg %d", prog, host, *p);
+    } else
+	p++;
+
+    tmp = get_xsockets (&rendez_vous1,
+			tcpp ? &rendez_vous2 : NULL);
+    if (tmp < 0)
+	return 1;
+    display_num = tmp;
+    if (tcpp)
+	sprintf (display, "localhost:%u", display_num);
+    else
+	sprintf (display, ":%u", display_num);
+    strncpy(xauthfile, tempnam("/tmp", NULL), xauthfile_size);
+    if (create_and_write_cookie (xauthfile, cookie, cookie_len))
+	return 1;
+    status_output (debugpp);
+    for (;;) {
+	fd_set fdset;
+	pid_t child;
+	int fd, thisfd;
+	int zero = 0;
+
+	FD_ZERO(&fdset);
+	if (rendez_vous1)
+	    FD_SET(rendez_vous1, &fdset);
+	if (rendez_vous2)
+	    FD_SET(rendez_vous2, &fdset);
+	if (select(FD_SETSIZE, &fdset, NULL, NULL, NULL) <= 0)
+	    continue;
+	if (rendez_vous1 && FD_ISSET(rendez_vous1, &fdset))
+	    thisfd = rendez_vous1;
+	else if (rendez_vous2 && FD_ISSET(rendez_vous2, &fdset))
+	    thisfd = rendez_vous2;
+	else
+	    continue;
+
+	fd = accept (thisfd, NULL, &zero);
+	if (fd < 0)
+	    if (errno == EINTR)
+		continue;
+	    else
+		err(1, "%s: accept", prog);
+
+	p = msg;
+	*p++ = NEW_CONN;
+	if (write_encrypted (otherside, msg, p - msg, schedule,
+			     &key, &me, &him) < 0)
+	    err (1, "%s: write to %s failed", prog, host);
+	len = read_encrypted (otherside, msg, sizeof(msg), &ret,
+			      schedule, &key, &him, &me);
+	if (len < 0)
+	    err (1, "%s: read from %s failed", prog, host);
+	p = (u_char *)ret;
+	if (*p == ERROR) {
+	    p++;
+	    p += krb_get_int (p, &tmp, 4, 0);
+	    errx (1, "%s: %s: %.*s", prog, host, tmp, p);
+	} else if (*p != NEW_CONN) {
+	    errx (1, "%s: %s: strange msg %d", prog, host, *p);
+	} else {
+	    p++;
+	    p += krb_get_int (p, &tmp, 4, 0);
+	}
+
+	++nchild;
+	child = fork ();
+	if (child < 0) {
+	    warn("%s: fork", prog);
+	    continue;
+	} else if (child == 0) {
+	    int s;
+	    u_char zero = 0;
+	    struct sockaddr_in addr;
+	    int addrlen = sizeof(addr);
+
+	    if (rendez_vous1)
+		close (rendez_vous1);
+	    if (rendez_vous2)
+		close (rendez_vous2);
+
+	    addr = him;
+	    close (otherside);
+
+	    addr.sin_port = htons(tmp);
+	    s = socket (AF_INET, SOCK_STREAM, 0);
+	    if (s < 0)
+		err(1, "%s: socket", prog);
+#if defined(TCP_NODELAY) && defined(HAVE_SETSOCKOPT)
+	    {
+		int one = 1;
+
+		setsockopt (s, IPPROTO_TCP, TCP_NODELAY, (void *)&one,
+			    sizeof(one));
+	    }
+#endif
+#if defined(SO_KEEPALIVE) && defined(HAVE_SETSOCKOPT)
+	    if (keepalivep) {
+		int one = 1;
+
+		setsockopt (s, SOL_SOCKET, SO_KEEPALIVE, (void *)&one,
+			    sizeof(one));
+	    }
+#endif
+
+	    if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) < 0)
+		err(1, "%s: connect", prog);
+
+	    return active_session (fd, s, &key, schedule);
+	} else {
+	    close (fd);
+	}
+    }
 }
 
 static void
@@ -481,24 +541,27 @@ usage(void)
 /*
  * kx - forward x connection over a kerberos-encrypted channel.
  *
- * passive mode if $DISPLAY begins with :
+ * passive mode if $DISPLAY begins with : */
- */
 
 int
 main(int argc, char **argv)
 {
      int passivep;
+     int keepalivep = 1;
      char *disp, *user = NULL;
      int debugp = 0, tcpp = 0;
      int c;
      int port = 0;
 
      prog = argv[0];
-     while((c = getopt(argc, argv, "tdl:p:")) != EOF) {
+     while((c = getopt(argc, argv, "ktdl:p:")) != EOF) {
 	 switch(c) {
 	 case 'd' :
 	     debugp = 1;
 	     break;
+	 case 'k':
+	     keepalivep = 0;
+	     break;
 	 case 't' :
 	     tcpp = 1;
 	     break;
@@ -521,10 +584,8 @@ main(int argc, char **argv)
 	  usage ();
      if (user == NULL) {
 	  struct passwd *p = k_getpwuid (getuid ());
-	  if (p == NULL) {
+	  if (p == NULL)
-	       fprintf (stderr, "%s: Who are you?\n", prog);
+	      errx(1, "%s: Who are you?\n", prog);
-	       return 1;
-	  }
 	  user = strdup (p->pw_name);
      }
      if (port == 0)
@@ -536,7 +597,7 @@ main(int argc, char **argv)
      signal (SIGUSR1, usr1handler);
      signal (SIGUSR2, usr2handler);
      if (passivep)
-	 return doit_passive (argv[0], user, debugp, port);
+	 return doit_passive (argv[0], user, debugp, keepalivep, port);
      else
-	 return doit_active  (argv[0], user, debugp, tcpp, port);
+	 return doit_active  (argv[0], user, debugp, keepalivep, tcpp, port);
 }

appl/kx/kx.h

@@ -47,6 +47,7 @@
 #endif
 
 #include <stdio.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 #include <signal.h>
@@ -128,8 +129,25 @@ int create_and_write_cookie (char *xauthfile,
 			     size_t sz);
 int suspicious_address (int sock, struct sockaddr_in addr);
 
+int
+write_encrypted (int fd, void *buf, size_t len, des_key_schedule schedule,
+		 des_cblock *session, struct sockaddr_in *me,
+		 struct sockaddr_in *him);
+
+int
+read_encrypted (int fd, void *buf, size_t len, void **ret,
+		des_key_schedule schedule, des_cblock *session,
+		struct sockaddr_in *him, struct sockaddr_in *me);
+
+
 #define KX_PORT 2111
 
 #define KX_VERSION "KXSERV.2"
 
 #define COOKIE_TYPE "MIT-MAGIC-COOKIE-1"
+
+enum { INIT = 0, ACK = 1, NEW_CONN = 2, ERROR = 3 };
+
+enum kx_flags { PASSIVE = 1, KEEP_ALIVE = 2 };
+
+typedef enum kx_flags kx_flags;

appl/kx/kxd.c

@@ -59,15 +59,28 @@ childhandler (int sig)
      SIGRETURN(0);
 }
 
-static int
+static void
-fatal (int fd, char *s)
+fatal (int fd, des_cblock *key, des_key_schedule schedule,
+       struct sockaddr_in *thisaddr,
+       struct sockaddr_in *thataddr,
+       char *format, ...)
 {
-     u_char err = 1;
+    u_char msg[1024];
+    u_char *p;
+    va_list args;
+    int len;
 
-     write (fd, &err, sizeof(err));
+    va_start(args, format);
-     write (fd, s, strlen(s)+1);
+    p = msg;
-     syslog(LOG_ERR, s);
+    *p++ = ERROR;
-     return err;
+    vsprintf (p + 4, format, args);
+    syslog (LOG_ERR, p + 4);
+    len = strlen (p + 4);
+    p += krb_put_int (len, p, 4);
+    p += len;
+    write_encrypted (fd, msg, p - msg, schedule, key, thisaddr, thataddr);
+    va_end(args);
+    exit (1);
 }
 
 static void
@@ -80,116 +93,150 @@ cleanup(void)
 }
 
 static int
-recv_conn (int sock, des_cblock *key, des_key_schedule schedule)
+recv_conn (int sock, des_cblock *key, des_key_schedule schedule,
+	   struct sockaddr_in *thisaddr,
+	   struct sockaddr_in *thataddr)
 {
      int status;
      KTEXT_ST ticket;
      AUTH_DAT auth;
      char user[ANAME_SZ + 1];
      char instance[INST_SZ + 1];
-     struct sockaddr_in thisaddr, thataddr;
      int addrlen;
      char version[KRB_SENDAUTH_VLEN];
-     u_char ok = 0;
      struct passwd *passwd;
      char remotehost[MaxHostNameLen];
+     void *ret;
+     int len;
+     u_char msg[1024], *p;
+     u_int32_t tmp;
+     int flags;
 
-     addrlen = sizeof(thisaddr);
+     addrlen = sizeof(*thisaddr);
-     if (getsockname (sock, (struct sockaddr *)&thisaddr, &addrlen) < 0 ||
+     if (getsockname (sock, (struct sockaddr *)thisaddr, &addrlen) < 0 ||
-	 addrlen != sizeof(thisaddr)) {
+	 addrlen != sizeof(*thisaddr)) {
-	  return 1;
+	 syslog (LOG_ERR, "getsockname: %m");
+	 exit (1);
      }
-     addrlen = sizeof(thataddr);
+     addrlen = sizeof(*thataddr);
-     if (getpeername (sock, (struct sockaddr *)&thataddr, &addrlen) < 0 ||
+     if (getpeername (sock, (struct sockaddr *)thataddr, &addrlen) < 0 ||
-	 addrlen != sizeof(thataddr)) {
+	 addrlen != sizeof(*thataddr)) {
-	  return 1;
+	 syslog (LOG_ERR, "getpeername: %m");
+	 exit (1);
      }
 
-     inaddr2str (thataddr.sin_addr, remotehost, sizeof(remotehost));
+     inaddr2str (thataddr->sin_addr, remotehost, sizeof(remotehost));
 
      k_getsockinst (sock, instance);
      status = krb_recvauth (KOPT_DO_MUTUAL, sock, &ticket, "rcmd", instance,
-			    &thataddr, &thisaddr, &auth, "", schedule,
+			    thataddr, thisaddr, &auth, "", schedule,
 			    version);
-     if (status != KSUCCESS ||
+     if (status != KSUCCESS)
-	 strncmp(version, KX_VERSION, KRB_SENDAUTH_VLEN) != 0) {
+	 errx(1, "%s: krb_recvauth: %s",
-	  return 1;
+	      prog, krb_get_err_text(status));
-     }
+     if( strncmp(version, KX_VERSION, KRB_SENDAUTH_VLEN) != 0)
+	 fatal(sock, key, schedule, thisaddr, thataddr,
+	       "Bad version %s", version);
      memcpy(key, &auth.session, sizeof(des_cblock));
-     if (krb_net_read (sock, user, sizeof(user)) != sizeof(user))
+
-	  return 1;
+     len = read_encrypted (sock, msg, sizeof(msg), &ret,
+			   schedule, key, thataddr, thisaddr);
+     if (len < 0)
+	 return 1;
+     p = (u_char *)ret;
+     if (*p != INIT)
+	 fatal(sock, key, schedule, thisaddr, thataddr,
+	       "Bad message");
+     p++;
+     p += krb_get_int (p, &tmp, 4, 0);
+     len = min(sizeof(user), tmp);
+     strncpy (user, p, len);
+     p += tmp;
+     user[len] = '\0';
+
      passwd = k_getpwnam (user);
      if (passwd == NULL)
-	  return fatal (sock, "Cannot find uid");
+	  fatal (sock, key, schedule, thisaddr, thataddr,
+		 "Cannot find uid");
      if (kuserok(&auth, user) != 0)
-	  return fatal (sock, "Permission denied");
+	  fatal (sock, key, schedule, thisaddr, thataddr,
+		 "%s is not allowed to login as %s",
+		 krb_unparse_name_long (auth.pname,
+					auth.pinst,
+					auth.prealm),
+		 user);
      if (setgid (passwd->pw_gid) ||
 	 initgroups(passwd->pw_name, passwd->pw_gid) ||
 	 setuid(passwd->pw_uid)) {
-	  return fatal (sock, "Cannot set uid");
+	 fatal (sock, key, schedule, thisaddr, thataddr,
+		"Cannot set uid");
      }
      syslog (LOG_INFO, "from %s(%s): %s -> %s",
 	     remotehost,
-	     inet_ntoa(thataddr.sin_addr),
+	     inet_ntoa(thataddr->sin_addr),
 	     krb_unparse_name_long (auth.pname, auth.pinst, auth.prealm),
 	     user);
-
      umask(077);
-     if (krb_net_write (sock, &ok, sizeof(ok)) != sizeof(ok))
+     flags = *p++;
-	  return 1;
+     if (!(flags & PASSIVE)) {
-
+	 p += krb_get_int (p, &tmp, 4, 0);
-     return 0;
+	 len = min(tmp, display_size);
-}
+	 strncpy (display, p, len);
-
+	 display[len] = '\0';
-static int
+	 p += tmp;
-start_session (int fd, int sock, des_cblock *key,
+	 p += krb_get_int (p, &tmp, 4, 0);
-	       des_key_schedule schedule)
+	 len = min(tmp, xauthfile_size);
-{
+	 strncpy (xauthfile, p, len);
-     u_char beg[12];
+	 p += tmp;
-     int bigendianp;
-     unsigned n, d, npad, dpad;
-     char *protocol_name, *protocol_data;
-     u_char zeros[6] = {0, 0, 0, 0, 0, 0};
-
-     if (krb_net_read (fd, beg, sizeof(beg)) != sizeof(beg))
-	  return 1;
-     if (krb_net_write (sock, beg, 6) != 6)
-	  return 1;
-     bigendianp = beg[0] == 'B';
-     if (bigendianp) {
-	  n = (beg[6] << 8) | beg[7];
-	  d = (beg[8] << 8) | beg[9];
-     } else {
-	  n = (beg[7] << 8) | beg[6];
-	  d = (beg[9] << 8) | beg[8];
      }
-     npad = (4 - (n % 4)) % 4;
+#if defined(SO_KEEPALIVE) && defined(HAVE_SETSOCKOPT)
-     dpad = (4 - (d % 4)) % 4;
+     if (flags & KEEP_ALIVE) {
-     protocol_name = malloc(n + npad);
+	 int one = 1;
-     protocol_data = malloc(d + dpad);
+
-     if (krb_net_read (fd, protocol_name, n + npad) != n + npad)
+	 setsockopt (sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&one,
-	  return 1;
+		     sizeof(one));
-     if (krb_net_read (fd, protocol_data, d + dpad) != d + dpad)
+     }
-	  return 1;
+#endif
-     if (strncmp (protocol_name, COOKIE_TYPE, strlen(COOKIE_TYPE)) != 0)
+     return flags;
-	  return 1;
+}
-     if (d != cookie_len ||
+
-	 memcmp (protocol_data, cookie, cookie_len) != 0)
+/*
-	  return 1;
+ *
-     if (krb_net_write (sock, zeros, 6) != 6)
+ */
-	  return 1;
+
-     return copy_encrypted (fd, sock, key, schedule);
+static int
+passive_session (int fd, int sock, des_cblock *key,
+		 des_key_schedule schedule)
+{
+    if (verify_and_remove_cookies (fd, sock))
+	return 1;
+    else
+	return copy_encrypted (fd, sock, key, schedule);
 }
 
 static int
-doit_conn (int fd, int meta_sock,
+active_session (int fd, int sock, des_cblock *key,
-	   des_cblock *key, des_key_schedule schedule)
+		des_key_schedule schedule)
+{
+    fd = connect_local_xsocket(0);
+
+    if (replace_cookie (fd, sock, xauthfile))
+	return 1;
+    else
+	return copy_encrypted (fd, sock, key, schedule);
+}
+
+static int
+doit_conn (int fd, int meta_sock, int flags,
+	   des_cblock *key, des_key_schedule schedule,
+	   struct sockaddr_in *thisaddr,
+	   struct sockaddr_in *thataddr)
 {
     int sock, sock2;
     int one = 1;
-    struct sockaddr_in thisaddr;
+    struct sockaddr_in addr;
     int addrlen;
-    char tmp[6];
+    u_char msg[1024], *p;
 
     sock = socket (AF_INET, SOCK_STREAM, 0);
     if (sock < 0) {
@@ -197,15 +244,27 @@ doit_conn (int fd, int meta_sock,
 	return 1;
     }
 #if defined(TCP_NODELAY) && defined(HAVE_SETSOCKOPT)
-    setsockopt (sock, IPPROTO_TCP, TCP_NODELAY, (void *)&one, sizeof(one));
+    {
+	int one = 1;
+	setsockopt (sock, IPPROTO_TCP, TCP_NODELAY, (void *)&one, sizeof(one));
+    }
 #endif
-    memset (&thisaddr, 0, sizeof(thisaddr));
+#if defined(SO_KEEPALIVE) && defined(HAVE_SETSOCKOPT)
-    if (bind (sock, (struct sockaddr *)&thisaddr, sizeof(thisaddr)) < 0) {
+     if (flags & KEEP_ALIVE) {
+	 int one = 1;
+
+	 setsockopt (sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&one,
+		     sizeof(one));
+     }
+#endif
+    memset (&addr, 0, sizeof(addr));
+    addr.sin_family = AF_INET;
+    if (bind (sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
 	syslog (LOG_ERR, "bind: %m");
 	return 1;
     }
-    addrlen = sizeof(thisaddr);
+    addrlen = sizeof(addr);
-    if (getsockname (sock, (struct sockaddr *)&thisaddr,
+    if (getsockname (sock, (struct sockaddr *)&addr,
 		     &addrlen) < 0) {
 	syslog (LOG_ERR, "getsockname: %m");
 	return 1;
@@ -214,11 +273,16 @@ doit_conn (int fd, int meta_sock,
 	syslog (LOG_ERR, "listen: %m");
 	return 1;
     }
-    sprintf (tmp, "%d", ntohs(thisaddr.sin_port));
+    p = msg;
-    if (krb_net_write (meta_sock, tmp, sizeof(tmp)) != sizeof(tmp)) {
+    *p++ = NEW_CONN;
+    p += krb_put_int (ntohs(addr.sin_port), p, 4);
+
+    if (write_encrypted (meta_sock, msg, p - msg, schedule, key,
+			 thisaddr, thataddr) < 0) {
 	syslog (LOG_ERR, "write: %m");
 	return 1;
     }
+
     sock2 = accept (sock, (struct sockaddr *)&thisaddr, &addrlen);
     if (sock2 < 0) {
 	syslog (LOG_ERR, "accept: %m");
@@ -226,39 +290,51 @@ doit_conn (int fd, int meta_sock,
     }
     close (sock);
     close (meta_sock);
-    return start_session (fd, sock2, key, schedule);
+
+    if (flags & PASSIVE)
+	return passive_session (fd, sock2, key, schedule);
+    else
+	return active_session (fd, sock2, key, schedule);
 }
 
 /*
  *
  */
 
-static int
+static void
-check_user_console (void)
+check_user_console (int fd, des_cblock *key, des_key_schedule schedule,
+		    struct sockaddr_in *thisaddr,
+		    struct sockaddr_in *thataddr)
 {
      struct stat sb;
 
      if (stat ("/dev/console", &sb) < 0)
-	  return fatal (0, "Cannot stat /dev/console");
+	 fatal (fd, key, schedule, thisaddr, thataddr,
+		"Cannot stat /dev/console");
      if (getuid() != sb.st_uid)
-	  return fatal (0, "Permission denied");
+	 fatal (fd, key, schedule, thisaddr, thataddr,
-     return 0;
+		"Permission denied");
 }
 
+/*
+ * Receive a connection on `sock' and process it.
+ */
+
 static int
 doit(int sock, int tcpp)
 {
-     u_char passivep;
      des_key_schedule schedule;
      des_cblock key;
      int localx, tcpx;
+     struct sockaddr_in me, him;
+     int flags;
+     u_char msg[1024], *p;
 
-     if (recv_conn (sock, &key, schedule))
+     flags = recv_conn (sock, &key, schedule, &me, &him);
-	  return 1;
+
-     if (krb_net_read (sock, &passivep, sizeof(passivep)) != sizeof(passivep))
+     if (flags & PASSIVE) {
-	  return 1;
-     if (passivep) {
 	  int tmp;
+	  int len;
 
 	  tmp = get_xsockets (&localx, tcpp ? &tcpx : NULL);
 	  if (tmp < 0)
@@ -268,19 +344,30 @@ doit(int sock, int tcpp)
 	       sprintf (display, "localhost:%u", display_num);
 	  else
 	       sprintf (display, ":%u", display_num);
-	  if (krb_net_write (sock, display, display_size) != display_size)
-	       return 1;
 	  strncpy(xauthfile, tempnam("/tmp", NULL), xauthfile_size);
-	  if (krb_net_write (sock, xauthfile, xauthfile_size)
-	      != xauthfile_size)
-	       return 1;
 	  if(create_and_write_cookie (xauthfile, cookie, cookie_len))
 	       return 1;
+
+	  p = msg;
+	  *p++ = ACK;
+	  len = strlen (display);
+	  p += krb_put_int (len, p, 4);
+	  strncpy (p, display, len);
+	  p += len;
+	  len = strlen (xauthfile);
+	  p += krb_put_int (len, p, 4);
+	  strncpy (p, xauthfile, len);
+	  p += len;
+	  
+	  if(write_encrypted (sock, msg, p - msg, schedule, &key,
+			      &me, &him) < 0) {
+	      syslog (LOG_ERR, "write: %m");
+	      return 1;
+	  }
 	  for (;;) {
 	       pid_t child;
 	       int fd;
 	       int zero = 0;
-	       int one = 1;
 	       fd_set fds;
 	       
 	       FD_ZERO(&fds);
@@ -316,10 +403,7 @@ doit(int sock, int tcpp)
 			syslog (LOG_ERR, "accept: %m");
 			return 1;
 		    }
-#if defined(TCP_NODELAY) && defined(HAVE_SETSOCKOPT)
+
-	       setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, (void *)&one,
-			   sizeof(one));
-#endif
 	       child = fork ();
 	       if (child < 0) {
 		   syslog (LOG_ERR, "fork: %m");
@@ -328,19 +412,52 @@ doit(int sock, int tcpp)
 		    close (localx);
 		    if (tcpp)
 			 close (tcpx);
-		    return doit_conn (fd, sock, &key, schedule);
+		    return doit_conn (fd, sock, flags,
+				      &key, schedule, &me, &him);
 	       } else {
 		    close (fd);
 	       }
 	  }
      } else {
-	  if (check_user_console ())
+	  check_user_console (sock, &key, schedule, &me, &him);
-	       return 1;
 
-	  localx = connect_local_xsocket (0);
+	  p = msg;
-	  if (localx < 0)
+	  *p++ = ACK;
-	       return 1;
+	  
-	  return copy_encrypted (localx, sock, &key, schedule);
+	  if(write_encrypted (sock, msg, p - msg, schedule, &key,
+			      &me, &him) < 0) {
+	      syslog (LOG_ERR, "write: %m");
+	      return 1;
+	  }
+	  for (;;) {
+	      pid_t child;
+	      int fd;
+	      int len;
+	      void *ret;
+	      
+	      len = read_encrypted (sock, msg, sizeof(msg), &ret,
+				    schedule, &key,
+				    &him, &me);
+	      if (len < 0) {
+		  syslog (LOG_ERR, "read: %m");
+		  return 1;
+	      }
+	      p = (u_char *)ret;
+	      if (*p != NEW_CONN) {
+		  syslog (LOG_ERR, "bad_message: %d", *p);
+		  return 1;
+	      }
+
+	      child = fork ();
+	      if (child < 0) {
+		  syslog (LOG_ERR, "fork: %m");
+		  return 1;
+	      } else if (child == 0) {
+		  return doit_conn (localx, sock, flags,
+				    &key, schedule, &me, &him);
+	      } else {
+	      }
+	  }
      }
 }