Account for peer-id in frame size calculation

Data channel packet using P_DATA_V2 will use three bytes extra for the
peer-id. This needs to be accounted for, otherwise OpenVPN will throw

  TCP/UDP packet too large on write to [AF_INET]10.1.1.1:1194

warnings.

Signed-off-by: Steffan Karger <[email protected]>
Acked-by: Lev Stipakov <[email protected]>
Message-Id: <[email protected]>
URL: http://article.gmane.org/gmane.network.openvpn.devel/9418
Signed-off-by: Gert Doering <[email protected]>
(cherry picked from commit f95010a)

Author: syzzer

src/openvpn/ssl.c

@@ -267,16 +267,14 @@ tls_get_cipher_name_pair (const char * cipher_name, size_t len) {
   return NULL;
 }
 
-/*
- * Max number of bytes we will add
- * for data structures common to both
- * data and control channel packets.
- * (opcode only). 
+/**
+ * Max number of bytes we will add for data structures common to both data and
+ * control channel packets (1 byte opcode + 3 bytes peer-id).
  */
 void
 tls_adjust_frame_parameters(struct frame *frame)
 {
-  frame_add_to_extra_frame (frame, 1); /* space for opcode */
+  frame_add_to_extra_frame (frame, 1 + 3); /* space for opcode + peer-id */
 }
 
 /*