Add BIGREQUEST extension support to nxproxy/nxcomp.feature/nxcomp-bigreq-support

 This work has been started by Paul Szarbo but has been discontinued
 before final completion. So, this is work in progress.

 For reference / communication history, see [1].

 [1] https://bugs.debian.org/766299

1 files changed, 9 insertions, 2 deletions

diff --git a/nxcomp/ServerReadBuffer.cpp b/nxcomp/ServerReadBuffer.cpp
index 96c146b77..069da2b45 100644
--- a/nxcomp/ServerReadBuffer.cpp
+++ b/nxcomp/ServerReadBuffer.cpp
@@ -108,14 +108,21 @@ int ServerReadBuffer::locateMessage(const unsigned char *start,
     {
       dataLength = 32 + (GetULONG(start + 4, bigEndian_) << 2);
     }
+    else if (*start == GenericEvent && *(start+1) != 0)
+    {
+      // X Generic Event Extension
+      dataLength = 32 + (GetULONG(start + 4, bigEndian_) << 2);
+    }
     else
     {
       dataLength = 32;
     }
 
-    if (dataLength < 32)
+// See WRITE_BUFFER_OVERFLOW_SIZE elsewhere
+// and also ENCODE_BUFFER_OVERFLOW_SIZE DECODE_BUFFER_OVERFLOW_SIZE.
+    if (dataLength < 32 || dataLength > 100*1024*1024)
     {
-      #ifdef TEST
+      #ifdef WARNING
       *logofs << "ServerReadBuffer: WARNING! Assuming length 32 "
               << "for suspicious message of length " << dataLength
               << ".\n" << logofs_flush;