code: func checkForCFHeaderMismatch(headers map[string]*wire.MsgCFHeaders,
  	idx int) bool {
  
  	// First, see if we have a mismatch.
  	hash := zeroHash
  	for _, msg := range headers {
  		if len(msg.FilterHashes) <= idx {
  			continue
  		}
  
  		if hash == zeroHash {
  			hash = *msg.FilterHashes[idx]
  			continue
  		}
  
  		if hash != *msg.FilterHashes[idx] {
  			// We've found a mismatch!
  			return true
  		}
  	}
  
  	return false
  }
docs: // checkForCFHeaderMismatch checks all peers' responses at a specific position
  // and detects a mismatch. It returns true if a mismatch has occurred.