zebra, lib: Add client proto & instance in zserv

Add client proto and instance number in all msg (request and
responses) to/form a label manager. This is required for a
label manager acting as 'proxy' (i.e. relaying messages towards
another label manager) to correctly deliver responses to the
requesting clients.

Signed-off-by: Fredi Raspall <fredi@voltanet.io>

1 files changed, 47 insertions, 4 deletions

diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
index 9353d7133..24f1748e2 100644
--- a/zebra/zapi_msg.c
+++ b/zebra/zapi_msg.c
@@ -887,6 +887,10 @@ static int zsend_assign_label_chunk_response(struct zserv *client,
 	zclient_create_header(s, ZEBRA_GET_LABEL_CHUNK, vrf_id);
 
 	if (lmc) {
+		/* proto */
+		stream_putc(s, lmc->proto);
+		/* instance */
+		stream_putw(s, lmc->instance);
 		/* keep */
 		stream_putc(s, lmc->keep);
 		/* start and end labels */
@@ -912,6 +916,12 @@ static int zsend_label_manager_connect_response(struct zserv *client,
 
 	zclient_create_header(s, ZEBRA_LABEL_MANAGER_CONNECT, vrf_id);
 
+	/* proto */
+	stream_putc(s, client->proto);
+
+	/* instance */
+	stream_putw(s, client->instance);
+
 	/* result */
 	stream_putc(s, result);
 
@@ -2398,6 +2408,23 @@ static void zread_label_manager_connect(struct zserv *client,
 stream_failure:
 	return;
 }
+static int msg_client_id_mismatch(const char *op, struct zserv *client,
+				  uint8_t proto, unsigned int instance)
+{
+	if (proto != client->proto) {
+		zlog_err("%s: msg vs client proto mismatch, client=%u msg=%u",
+				op, client->proto, proto);
+		return 1;
+	}
+
+	if (instance != client->instance) {
+		zlog_err("%s: msg vs client instance mismatch, client=%u msg=%u",
+				op, client->instance, instance);
+		return 1;
+	}
+
+	return 0;
+}
 
 static void zread_get_label_chunk(struct zserv *client, struct stream *msg,
 				  vrf_id_t vrf_id)
@@ -2406,21 +2433,29 @@ static void zread_get_label_chunk(struct zserv *client, struct stream *msg,
 	uint8_t keep;
 	uint32_t size;
 	struct label_manager_chunk *lmc;
+	uint8_t proto;
+	unsigned short instance;
 
 	/* Get input stream.  */
 	s = msg;
 
 	/* Get data. */
+	STREAM_GETC(s, proto);
+	STREAM_GETW(s, instance);
 	STREAM_GETC(s, keep);
 	STREAM_GETL(s, size);
 
+	/* detect client vs message (proto,instance) mismatch */
+	if (msg_client_id_mismatch("Get-label-chunk", client, proto, instance))
+		return;
+
 	lmc = assign_label_chunk(client->proto, client->instance, keep, size);
 	if (!lmc)
-		zlog_err("%s: Unable to assign Label Chunk of size %u",
-			 __func__, size);
+		zlog_err("Unable to assign Label Chunk of size %u to %s instance %u",
+			 size, zebra_route_string(client->proto), client->instance);
 	else
-		zlog_debug("Assigned Label Chunk %u - %u to %u", lmc->start,
-			   lmc->end, keep);
+		zlog_debug("Assigned Label Chunk %u - %u to %s instance %u", lmc->start,
+			   lmc->end, zebra_route_string(client->proto), client->instance);
 	/* send response back */
 	zsend_assign_label_chunk_response(client, vrf_id, lmc);
 
@@ -2432,14 +2467,22 @@ static void zread_release_label_chunk(struct zserv *client, struct stream *msg)
 {
 	struct stream *s;
 	uint32_t start, end;
+	uint8_t proto;
+	unsigned short instance;
 
 	/* Get input stream.  */
 	s = msg;
 
 	/* Get data. */
+	STREAM_GETC(s, proto);
+	STREAM_GETW(s, instance);
 	STREAM_GETL(s, start);
 	STREAM_GETL(s, end);
 
+	/* detect client vs message (proto,instance) mismatch */
+	if (msg_client_id_mismatch("Release-label-chunk", client, proto, instance))
+		return;
+
 	release_label_chunk(client->proto, client->instance, start, end);
 
 stream_failure: