From 4140d9156ba640d4c3f9099b9b0f88c1922c38a5 Mon Sep 17 00:00:00 2001
From: Constantin Kaplinsky <const@tightvnc.com>
Date: Tue, 12 Sep 2006 14:10:14 +0000
Subject: [PATCH] Finished support for TightVNC protocol extensions in the
 server code. Now "no authentication" case is handled correctly.

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@670 3789f03b-4d11-0410-bbf8-ca57d06f2519
---
 common/rfb/CapsList.h      |  5 +++++
 common/rfb/SConnection.cxx | 41 +++++++++++++++++++++++++-------------
 2 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/common/rfb/CapsList.h b/common/rfb/CapsList.h
index b8fb8e85..a267e933 100644
--- a/common/rfb/CapsList.h
+++ b/common/rfb/CapsList.h
@@ -48,6 +48,11 @@ namespace rfb {
     // Current number of capabilities in the list.
     int getSize() const { return numEnabled(); }
 
+    // Does the list include nothing more than one particular capability?
+    bool includesOnly(rdr::U32 code) {
+      return (numEnabled() == 1 && getByOrder(0) == code);
+    }
+
     // Add capability ("standard" vendor).
     void addStandard(rdr::U32 code, const char *name);
     // Add capability (TightVNC vendor).
diff --git a/common/rfb/SConnection.cxx b/common/rfb/SConnection.cxx
index 11da2a86..9fbf5f48 100644
--- a/common/rfb/SConnection.cxx
+++ b/common/rfb/SConnection.cxx
@@ -205,6 +205,7 @@ void SConnection::offerTunneling()
 
   // Advertise our tunneling capabilities (currently, nothing to advertise).
   os->writeU32(nTypes);
+  os->flush();
 
   if (nTypes) {
     // NOTE: Never executed in current version.
@@ -237,35 +238,44 @@ void SConnection::offerAuthentication()
   //       only the standard security types: secTypeNone and secTypeVncAuth.
   securityFactory->getSecTypes(&secTypes, reverseConnection);
 
-  if (secTypes.empty())
-    throwConnFailedException("No supported security types");
-
-  // FIXME: Send an empty list for "no authentication".
-
   CapsList caps;
   for (i = secTypes.begin(); i != secTypes.end(); i++) {
     // FIXME: Capability info should be provided by SSecurity objects.
     switch (*i) {
     case secTypeNone:     caps.addStandard(*i, "NOAUTH__"); break;
     case secTypeVncAuth:  caps.addStandard(*i, "VNCAUTH_"); break;
+    default:
+      // This should not ever happen.
+      vlog.error("not offering unknown security type %d", (int)*i);
     }
   }
-  os->writeU32(caps.getSize());
-  caps.write(os);
-  os->flush();
 
-  // FIXME: Capability list is never empty here, otherwise
-  //        we would not expect authentication type message.
-  state_ = RFBSTATE_TIGHT_AUTH_TYPE;
+  if (caps.getSize() < 1)
+    throwConnFailedException("No supported security types");
+
+  if (caps.includesOnly(secTypeNone)) {
+    // Special case - if caps includes nothing else than secTypeNone, we send
+    // an empty capability list and do not expect security type selection from
+    // the client.
+    os->writeU32(0);
+    os->flush();
+    processSecurityType(secTypeNone);
+  } else {
+    // Normal case - sending the list of authentication capabilities.
+    os->writeU32(caps.getSize());
+    caps.write(os);
+    os->flush();
+    state_ = RFBSTATE_TIGHT_AUTH_TYPE;
+  }
 }
 
 void SConnection::processAuthTypeMsg()
 {
   vlog.debug("processing authentication type message (TightVNC extension)");
 
-  // FIXME: Security types and TightVNC's auth types should be distinguished
-  //        although we use the same codes for NoAuth and VncAuth.
-
+  // NOTE: Currently, we support only the standard security types, so we
+  //       just pass TightVNC authentication type for standard processing,
+  //       just as it was usual RFB security type.
   int secType = is->readU32();
   processSecurityType(secType);
 }
@@ -431,6 +441,9 @@ void SConnection::sendInteractionCaps()
       case encodingHextile:  ecaps.addStandard(i, "HEXTILE_"); break;
       case encodingZRLE:     ecaps.addStandard(i, "ZRLE____"); break;
       case encodingTight:    ecaps.addTightExt(i, "TIGHT___"); break;
+      default:
+        // This should not ever happen.
+        vlog.error("not advertising unknown encoding type %d", (int)i);
       }
     }
   }
-- 
2.39.5