From 8490d289fbef44e2ff2665cadebce730cef04792 Mon Sep 17 00:00:00 2001
From: Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
Date: Fri, 5 Jun 2015 11:57:35 +0200
Subject: [PATCH] unify message validation across S2SS server and OPAL and
 GTFPGA PPC clients

---
 clients/opal_udp/models/send_receive/include/msg.h | 10 ++++++++++
 clients/opal_udp/models/send_receive/src/msg.c     | 13 +++++++++++++
 clients/opal_udp/models/send_receive/src/s2ss.c    | 13 ++++---------
 3 files changed, 27 insertions(+), 9 deletions(-)

diff --git a/clients/opal_udp/models/send_receive/include/msg.h b/clients/opal_udp/models/send_receive/include/msg.h
index 060cc29ad..69fdd15f9 100644
--- a/clients/opal_udp/models/send_receive/include/msg.h
+++ b/clients/opal_udp/models/send_receive/include/msg.h
@@ -11,5 +11,15 @@
 
 void msg_swap(struct msg *m);
 
+/** Check the consistency of a message.
+ *
+ * The functions checks the header fields of a message.
+ *
+ * @param m A pointer to the message
+ * @retval 0 The message header is valid.
+ * @retval <0 The message header is invalid.
+ */
+int msg_verify(struct msg *m);
+
 #endif /* _MSG_H_ */
 
diff --git a/clients/opal_udp/models/send_receive/src/msg.c b/clients/opal_udp/models/send_receive/src/msg.c
index 19acdca14..86d23504d 100644
--- a/clients/opal_udp/models/send_receive/src/msg.c
+++ b/clients/opal_udp/models/send_receive/src/msg.c
@@ -22,3 +22,16 @@ void msg_swap(struct msg *m)
 	m->endian ^= 1;
 }
 
+int msg_verify(struct msg *m)
+{
+	if      (m->version != MSG_VERSION)
+		return -1;
+	else if (m->type    != MSG_TYPE_DATA)
+		return -2;
+	else if ((m->length <= 0) || (m->length > MSG_VALUES))
+		return -3;
+	else if ((m->rsvd1 != 0)  || (m->rsvd2 != 0))
+		return -4;
+	else
+		return 0;
+}
\ No newline at end of file
diff --git a/clients/opal_udp/models/send_receive/src/s2ss.c b/clients/opal_udp/models/send_receive/src/s2ss.c
index 34b714aa6..753131cb2 100644
--- a/clients/opal_udp/models/send_receive/src/s2ss.c
+++ b/clients/opal_udp/models/send_receive/src/s2ss.c
@@ -187,15 +187,10 @@ static void *RecvFromIPPort(void *arg)
 /******* FORMAT TO SPECIFIC PROTOCOL HERE ******************************/
 			n  = RecvPacket((char *) &msg, sizeof(msg), 1.0);
 
-			/** @todo: Check and ntohs() sequence number! */
-
-			if (msg.version != MSG_VERSION) {
-				OpalPrint("%s: Received message with unknown version. Skipping..\n", PROGNAME);
-				continue;
-			}
-			else if (msg.type != MSG_TYPE_DATA) {
-				OpalPrint("%s: Received no data. Skipping..\n", PROGNAME);
-				continue;
+			int ret = msg_verify(m);
+			if (ret) {
+				printf("Dropping invalid message (reason=%d)\r\n", ret);
+				goto out;
 			}
 			
 			/** @todo: We may check the sequence number here. */