From de126fa104aaeabbc66b5dd59da9d07da2f0fd97 Mon Sep 17 00:00:00 2001
From: SS Roop <sairoop@elear.solutions>
Date: Tue, 12 Feb 2019 23:02:59 +0530
Subject: [PATCH] Add channel disconnection fix when node blacklisted

---
 src/graph.c     |  4 +++-
 src/meshlink.c  | 55 +++++++++++++++++++++++++++++++++++++++++++++++--
 src/net_setup.c | 21 +++++++++++++++++++
 src/utcp        |  2 +-
 4 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/src/graph.c b/src/graph.c
index 9b0184b0..19a33e2e 100644
--- a/src/graph.c
+++ b/src/graph.c
@@ -229,7 +229,9 @@ static void check_reachability(meshlink_handle_t *mesh) {
 
 			timeout_del(&mesh->loop, &n->mtutimeout);
 
-			update_node_status(mesh, n);
+			if(!n->status.blacklisted) {
+				update_node_status(mesh, n);
+			}
 
 			if(!n->status.reachable) {
 				update_node_udp(mesh, n, NULL);
diff --git a/src/meshlink.c b/src/meshlink.c
index d0944527..8f0f82d1 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -1732,6 +1732,13 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 		return false;
 	}
 
+	node_t *n = (node_t *)destination;
+
+	if(n->status.blacklisted) {
+		logger(mesh, MESHLINK_ERROR, "Node %s blacklisted, dropping packet\n", n->name);
+		return false;
+	}
+
 	// Prepare the packet
 	vpn_packet_t *packet = malloc(sizeof(*packet));
 
@@ -2773,6 +2780,20 @@ void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 
 	node_t *n;
 	n = (node_t *)node;
+
+	if(n == mesh->self) {
+		logger(mesh, MESHLINK_ERROR, "%s blacklisting itself?\n", node->name);
+		meshlink_errno = MESHLINK_EINVAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
+		return;
+	}
+
+	if(n->status.blacklisted) {
+		logger(mesh, MESHLINK_DEBUG, "Node %s already blacklisted\n", node->name);
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
+		return;
+	}
+
 	n->status.blacklisted = true;
 	logger(mesh, MESHLINK_DEBUG, "Blacklisted %s.\n", node->name);
 
@@ -2786,6 +2807,18 @@ void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		}
 	}
 
+	utcp_abort_all_connections(n->utcp);
+
+	n->mtu = 0;
+	n->minmtu = 0;
+	n->maxmtu = MTU;
+	n->mtuprobes = 0;
+	n->status.udp_confirmed = false;
+
+	if(n->status.reachable) {
+		update_node_status(mesh, n);
+	}
+
 	pthread_mutex_unlock(&(mesh->mesh_mutex));
 }
 
@@ -2798,9 +2831,22 @@ void meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	node_t *n = (node_t *)node;
+
+	if(!n->status.blacklisted) {
+		logger(mesh, MESHLINK_DEBUG, "Node %s was already whitelisted\n", node->name);
+		meshlink_errno = MESHLINK_EINVAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
+		return;
+	}
+
 	n->status.blacklisted = false;
 
-	//TODO: remove blacklisted = yes from the config file
+	if(n->status.reachable) {
+		update_node_status(mesh, n);
+	}
+
+	//Remove blacklisting from the config file
+	append_config_file(mesh, n->name, "blacklisted", NULL);
 
 	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return;
@@ -2989,6 +3035,11 @@ meshlink_channel_t *meshlink_channel_open_ex(meshlink_handle_t *mesh, meshlink_n
 		}
 	}
 
+	if(n->status.blacklisted) {
+		logger(mesh, MESHLINK_ERROR, "Cannot open a channel with blacklisted node\n");
+		return NULL;
+	}
+
 	meshlink_channel_t *channel = xzalloc(sizeof(*channel));
 	channel->node = n;
 	channel->receive_cb = cb;
@@ -3072,7 +3123,7 @@ void update_node_status(meshlink_handle_t *mesh, node_t *n) {
 	}
 
 	if(mesh->node_status_cb) {
-		mesh->node_status_cb(mesh, (meshlink_node_t *)n, n->status.reachable);
+		mesh->node_status_cb(mesh, (meshlink_node_t *)n, n->status.reachable && !n->status.blacklisted);
 	}
 }
 
diff --git a/src/net_setup.c b/src/net_setup.c
index 47ed32e0..70ed294e 100644
--- a/src/net_setup.c
+++ b/src/net_setup.c
@@ -190,6 +190,26 @@ exit:
 	return n->submesh != NULL;
 }
 
+bool node_read_blacklist_status(meshlink_handle_t *mesh, node_t *n) {
+
+	splay_tree_t *config_tree;
+	bool blacklist_status;
+
+	init_configuration(&config_tree);
+
+	if(!read_host_config(mesh, config_tree, n->name)) {
+		goto exit;
+	}
+
+	if(get_config_bool(lookup_config(config_tree, "blacklisted"), &blacklist_status)) {
+		n->status.blacklisted = blacklist_status;
+	}
+
+exit:
+	exit_configuration(&config_tree);
+	return n->status.blacklisted;
+}
+
 bool node_write_devclass(meshlink_handle_t *mesh, node_t *n) {
 
 	if((int)n->devclass < 0 || n->devclass > _DEV_CLASS_MAX) {
@@ -292,6 +312,7 @@ void load_all_nodes(meshlink_handle_t *mesh) {
 		n->name = xstrdup(ent->d_name);
 		node_read_devclass(mesh, n);
 		node_read_submesh(mesh, n);
+		node_read_blacklist_status(mesh, n);
 		node_add(mesh, n);
 	}
 
diff --git a/src/utcp b/src/utcp
index fad2787f..f1035e97 160000
--- a/src/utcp
+++ b/src/utcp
@@ -1 +1 @@
-Subproject commit fad2787f2394bad3cf105ca5b4cf411db6d34aa6
+Subproject commit f1035e971bb894203bdfba6cafbaf0bb30f197eb
-- 
2.39.5