gtphub: track tunnels explicitly.

So far, gtphub worked perfectly by only tracking single TEIs ... for probably
most uses. But a Ctrl plane tunnel may have expired despite a still active
corresponding User plane tunnel. The User plane would continue to work
indefinitely, but if any Ctrl messages followed after more than six hours of
Ctrl silence, they would have been dropped due to an expired TEI mapping.

We want to
- combine expiry of a user TEI with its ctrl TEI. (done in this patch)
- upon delete PDP context, remove both user and ctrl TEI mappings. (future)
- when a peer indicates a restart counter bump, invalidate its tunnels.
  (future)

To facilitate these, track tunnels, complete with both SGSN's and GGSN's
address, original and replaced TEIs, all for both user and ctrl plane, in a
single struct. A single expiry entry handles the entire tunnel, instead of
previously four separate expiries for each endpoint identifier.

Add the concept of a "side", being either GGSN or SGSN, to index tunnel
endpoint structs, and so on.

Track the originating side in the gtp_packet_desc.

Add header_tei_rx: set_tei() overwrites header_tei, but the originally received
header TEI is still needed to match a Create PDP Context Response up with its
Request (and for logging).

Adjust the test suite to expect tunnel listing strings instead of TEI mappings,
with a bonus of making it a lot easier to grok, and including the IP addresses.

Add regression test for refreshing tunnel expiry upon use.

Note: the current implementation is as slow as can possibly be, iterating all
the tunnels all the time. Optimizations are kept for a future commit, on
purpose.

BTW, the sequence number mapping/unmapping structures remain unchanged.

Sponsored-by: On-Waves ehi

1 files changed, 69 insertions, 89 deletions

diff --git a/openbsc/src/gprs/gtphub_vty.c b/openbsc/src/gprs/gtphub_vty.c
index 602508854..f99f81803 100644
--- a/openbsc/src/gprs/gtphub_vty.c
+++ b/openbsc/src/gprs/gtphub_vty.c
@@ -280,132 +280,112 @@ static void show_peers_summary(struct vty *vty)
 }
 */
 
-static void show_tei_maps_summary(struct vty *vty)
+static void show_tunnels_summary(struct vty *vty)
 {
 	time_t now = gtphub_now();
 
-	unsigned long long int count_all = 0; /* ...just joking. */
-
 	const int w = 36;
-	int max_expiry = g_hub->expire_tei_maps.expiry_in_seconds;
+	int max_expiry = g_hub->expire_slowly.expiry_in_seconds;
 	float seconds_per_step = ((float)max_expiry) / w;
 
 	/* Print TEI mapping expiry in an ASCII histogram, like:
 	     TEI map summary
 	       Legend:  '_'=0  '.'<=1%  ':'<=2%  '|'<=10%  '#'>10%  (10.0 m/step)
-	       CTRL: 30 mappings, valid for 360m[#__:.____|___.____:__.______________]1m
-	       USER: 30 mappings, valid for 360m[#__:.____|___.____:__.______________]1m
+	       CTRL: 30 mappings, valid for 360m[#  :.    |   .    :  .              ]1m
+	       USER: 30 mappings, valid for 360m[#  :.    |   .    :  .              ]1m
 	       4 TEI mappings in total, last expiry in 359.4 min
 	 */
 	vty_out(vty,
-		"TEI map summary%s"
-		"  Legend:  '_'=0  '.'<=1%%  ':'<=2%%  '|'<=10%%  '#'>10%%  (%.1f m/step)%s",
+		"Tunnels summary%s"
+		"  Legend:  ' '=0  '.'<=1%%  ':'<=2%%  '|'<=10%%  '#'>10%%  (%.1f m/step)%s",
 		VTY_NEWLINE,
 		seconds_per_step / 60.,
 		VTY_NEWLINE);
 
 	int last_expiry = 0;
-	int plane_idx;
-	for (plane_idx = 0; plane_idx < GTPH_PLANE_N; plane_idx++) {
 
-		unsigned int count = 0;
+	unsigned int count = 0;
 
-		int histogram[w];
-		memset(histogram, 0, sizeof(histogram));
+	int histogram[w];
+	memset(histogram, 0, sizeof(histogram));
 
-		struct nr_mapping *m;
-		llist_for_each_entry(m, &g_hub->tei_map[plane_idx].mappings, entry) {
-			count ++;
-			int expiry = m->expiry_entry.expiry - now;
-			last_expiry = (last_expiry > expiry) ? last_expiry : expiry;
+	struct gtphub_tunnel *t;
+	llist_for_each_entry(t, &g_hub->tunnels, entry) {
+		count ++;
+		int expiry = t->expiry_entry.expiry - now;
+		last_expiry = (last_expiry > expiry) ? last_expiry : expiry;
 
-			int hi = ((float)expiry) / seconds_per_step;
-			if (hi < 0)
-				hi = 0;
-			if (hi > (w - 1))
-				hi = w - 1;
-			histogram[hi] ++;
-		}
+		int hi = ((float)expiry) / seconds_per_step;
+		if (hi < 0)
+			hi = 0;
+		if (hi > (w - 1))
+			hi = w - 1;
+		histogram[hi] ++;
+	}
 
-		vty_out(vty,
-			"  %4s: %u mappings, valid for %dm[",
-			gtphub_plane_idx_names[plane_idx],
-			count, max_expiry / 60);
-
-		int i;
-		for (i = w - 1; i >= 0; i--) {
-			char c;
-			int val = histogram[i];
-			int percent = 100. * val / count;
-			if (!val)
-				c = '_';
-			else if (percent <= 1)
-				c = '.';
-			else if (percent <= 2)
-				c = ':';
-			else if (percent <= 10)
-				c = '|';
-			else c = '#';
-			vty_out(vty, "%c", c);
-		}
-		vty_out(vty, "]1m%s", VTY_NEWLINE);
-
-		count_all += count;
+	vty_out(vty,
+		"  %u tunnels, valid for %dm[",
+		count, max_expiry / 60);
+
+	int i;
+	for (i = w - 1; i >= 0; i--) {
+		char c;
+		int val = histogram[i];
+		int percent = 100. * val / count;
+		if (!val)
+			c = ' ';
+		else if (percent <= 1)
+			c = '.';
+		else if (percent <= 2)
+			c = ':';
+		else if (percent <= 10)
+			c = '|';
+		else c = '#';
+		vty_out(vty, "%c", c);
 	}
-	vty_out(vty, "  %llu TEI mappings in total, last expiry in %.1f min%s",
-		count_all,
+	vty_out(vty, "]1m%s", VTY_NEWLINE);
+
+	vty_out(vty, "  last expiry in %.1f min%s",
 		((float)last_expiry) / 60.,
 		VTY_NEWLINE);
 }
 
-static void show_tei_maps_all(struct vty *vty)
+static void show_tunnels_all(struct vty *vty)
 {
 	time_t now = gtphub_now();
 
-	unsigned long long int count_all = 0; /* ...just joking. */
+	vty_out(vty, "All tunnels:%s"
+		"Legend: SGSN <-> GGSN, with each:%s"
+		"        <IP-Ctrl>[/<IP-User>] (<TEI-Ctrl>=<mapped>/<TEI-User>=<mapped>)%s",
+		VTY_NEWLINE, VTY_NEWLINE, VTY_NEWLINE);
 
-	vty_out(vty, "All TEI mappings:%s", VTY_NEWLINE);
-	int plane_idx;
-	for (plane_idx = 0; plane_idx < GTPH_PLANE_N; plane_idx++) {
+	unsigned int count = 0;
+	unsigned int incomplete = 0;
+	struct gtphub_tunnel *t;
+	llist_for_each_entry(t, &g_hub->tunnels, entry) {
 		vty_out(vty,
-			"- %s Plane:%s"
-			"  (timeout) replaced-TEI <--> original-TEI from-peer%s",
-			gtphub_plane_idx_names[plane_idx],
-			VTY_NEWLINE, VTY_NEWLINE);
-
-		unsigned int count = 0;
-		struct nr_mapping *m;
-		llist_for_each_entry(m, &g_hub->tei_map[plane_idx].mappings, entry) {
-			struct gtphub_peer_port *pp = m->origin;
-			vty_out(vty,
-				"  (%4dm) %8x <--> %8x %s",
-				-(int)((m->expiry_entry.expiry - now) / 60),
-				(uint32_t)m->repl,
-				(uint32_t)m->orig,
-				gsn_addr_to_str(&pp->peer_addr->addr));
-			if (pp->port != gtphub_plane_idx_default_port[plane_idx])
-				vty_out(vty, " port %d", (int)pp->port);
-			vty_out(vty, VTY_NEWLINE);
-			count ++;
-		}
-		vty_out(vty, "  (%u %s TEI mappings)%s", count,
-			gtphub_plane_idx_names[plane_idx], VTY_NEWLINE);
-		count_all += count;
+			"(%4dm) %s%s",
+			-(int)((t->expiry_entry.expiry - now) / 60),
+			gtphub_tunnel_str(t),
+			VTY_NEWLINE);
+		count ++;
+		if (!gtphub_tunnel_complete(t))
+			incomplete ++;
 	}
-	vty_out(vty, "- %llu TEI mappings in total%s", count_all, VTY_NEWLINE);
+	vty_out(vty, "Total: %u tunnels%s", count, VTY_NEWLINE);
 }
 
-DEFUN(show_gtphub_tei_summary, show_gtphub_tei_summary_cmd, "show gtphub tei summary",
-      SHOW_STR "TEI mappings summary")
+DEFUN(show_gtphub_tunnels_summary, show_gtphub_tunnels_summary_cmd, "show gtphub tunnels summary",
+      SHOW_STR "Summary of all tunnels")
 {
-	show_tei_maps_summary(vty);
+	show_tunnels_summary(vty);
 	return CMD_SUCCESS;
 }
 
-DEFUN(show_gtphub_tei_dump, show_gtphub_tei_dump_cmd, "show gtphub tei dump",
-      SHOW_STR "Dump all current TEI mappings")
+DEFUN(show_gtphub_tunnels_list, show_gtphub_tunnels_list_cmd, "show gtphub tunnels list",
+      SHOW_STR "List all tunnels")
 {
-	show_tei_maps_all(vty);
+	show_tunnels_all(vty);
 	return CMD_SUCCESS;
 }
 
@@ -413,7 +393,7 @@ DEFUN(show_gtphub, show_gtphub_cmd, "show gtphub all",
       SHOW_STR "Display information about the GTP hub")
 {
 	show_bind_stats_all(vty);
-	show_tei_maps_summary(vty);
+	show_tunnels_summary(vty);
 	return CMD_SUCCESS;
 }
 
@@ -424,8 +404,8 @@ int gtphub_vty_init(struct gtphub *global_hub, struct gtphub_cfg *global_cfg)
 	g_cfg = global_cfg;
 
 	install_element_ve(&show_gtphub_cmd);
-	install_element_ve(&show_gtphub_tei_summary_cmd);
-	install_element_ve(&show_gtphub_tei_dump_cmd);
+	install_element_ve(&show_gtphub_tunnels_summary_cmd);
+	install_element_ve(&show_gtphub_tunnels_list_cmd);
 
 	install_element(CONFIG_NODE, &cfg_gtphub_cmd);
 	install_node(&gtphub_node, config_write_gtphub);