ppp: Add rca callback

When the other side acks our options, then let us apply these options
locally and start using them

gatchat/ppp_cp.c

@@ -997,8 +997,7 @@ static guint8 pppcp_process_configure_ack(struct pppcp_data *data,
 {
 	guint len;
 	GList *list;
-	struct ppp_option *acked_option;
-	guint i = 0;
+	guint i;
 	const struct pppcp_action *action = data->action;
 
 	pppcp_trace(data);
@@ -1013,40 +1012,34 @@ static guint8 pppcp_process_configure_ack(struct pppcp_data *data,
 	}
 
 	/*
-	 * check each acked option.  If it is what we requested,
-	 * then we can apply these option values.
-	 *
-	 * XXX what if it isn't?  Do this correctly -- for now
-	 * we are just going to assume that all options matched
-	 * and apply them.
+	 * First we must sanity check that all config options acked are
+	 * equal to the config options sent and are in the same order.
+	 * If this is not the case, then silently drop the packet
 	 */
-	while (i < len) {
-		acked_option = extract_ppp_option(data, &packet->data[i]);
-		if (acked_option == NULL)
-			break;
+	for (i = 0, list = data->config_options; list; list = list->next) {
+		struct ppp_option *sent_option = list->data;
 
-		list = g_list_find_custom(data->config_options,
-				GUINT_TO_POINTER((guint) acked_option->type),
-				is_option);
-		if (list) {
-			/*
-			 * once we've applied the option, delete it from
-			 * the config_options list.
-			 */
-			if (action->option_process)
-				action->option_process(data, acked_option);
+		if (sent_option->type != packet->data[i])
+			return 0;
 
-			g_free(list->data);
-			data->config_options =
-				g_list_delete_link(data->config_options, list);
-		} else
-			g_printerr("oops -- found acked option %d we didn't request\n", acked_option->type);
+		if (sent_option->length != packet->data[i + 1])
+			return 0;
 
-		/* skip ahead to the next option */
-		i += acked_option->length;
+		if (memcmp(sent_option->data, packet->data + i + 2,
+						sent_option->length) != 0)
+			return 0;
 
-		g_free(acked_option);
+		i += packet->data[i + 1];
 	}
+
+	/* Otherwise, apply local options */
+	if (action->rca)
+		action->rca(data, packet);
+
+	g_list_foreach(data->config_options, (GFunc)g_free, NULL);
+	g_list_free(data->config_options);
+	data->config_options = NULL;
+
 	return RCA;
 }
 

gatchat/ppp_cp.h

@@ -49,6 +49,13 @@ enum pppcp_code {
 	PPPCP_CODE_TYPE_DISCARD_REQUEST
 };
 
+struct pppcp_packet {
+	guint8 code;
+	guint8 identifier;
+	guint16 length;
+	guint8 data[0];
+} __attribute__((packed));
+
 struct ppp_option_iter {
 	guint16 max;
 	guint16 pos;
@@ -63,19 +70,14 @@ struct pppcp_action {
 	void (*this_layer_down)(struct pppcp_data *data);
 	void (*this_layer_started)(struct pppcp_data *data);
 	void (*this_layer_finished)(struct pppcp_data *data);
+	/* Remote side acked these options, we can now use them */
+	void (*rca)(struct pppcp_data *pppcp, const struct pppcp_packet *pkt);
 	enum option_rval (*option_scan)(struct pppcp_data *pppcp,
 					struct ppp_option *option);
 	void (*option_process)(struct pppcp_data *data,
 				struct ppp_option *option);
 };
 
-struct pppcp_packet {
-	guint8 code;
-	guint8 identifier;
-	guint16 length;
-	guint8 data[0];
-} __attribute__((packed));
-
 void ppp_option_iter_init(struct ppp_option_iter *iter,
 					const struct pppcp_packet *packet);
 gboolean ppp_option_iter_next(struct ppp_option_iter *iter);

gatchat/ppp_ipcp.c

@@ -108,6 +108,26 @@ static void ipcp_finished(struct pppcp_data *data)
 	g_print("ipcp finished\n");
 }
 
+static void ipcp_rca(struct pppcp_data *pppcp,
+					const struct pppcp_packet *packet)
+{
+	struct ipcp_data *ipcp = pppcp_get_data(pppcp);
+	struct ppp_option_iter iter;
+
+	ppp_option_iter_init(&iter, packet);
+
+	while (ppp_option_iter_next(&iter) == TRUE) {
+		switch (ppp_option_iter_get_type(&iter)) {
+		case IP_ADDRESS:
+			memcpy(ipcp->ip_address,
+					ppp_option_iter_get_data(&iter), 4);
+			break;
+		default:
+			break;
+		}
+	}
+}
+
 /*
  * Scan the option to see if it is acceptable, unacceptable, or rejected
  */
@@ -136,9 +156,6 @@ static void ipcp_option_process(struct pppcp_data *pppcp,
 	struct ipcp_data *ipcp = pppcp_get_data(pppcp);
 
 	switch (option->type) {
-	case IP_ADDRESS:
-		memcpy(ipcp->ip_address, option->data, 4);
-		break;
 	case PRIMARY_DNS_SERVER:
 		memcpy(ipcp->primary_dns, option->data, 4);
 		break;
@@ -162,6 +179,7 @@ struct pppcp_action ipcp_action = {
 	.this_layer_down	= ipcp_down,
 	.this_layer_started	= ipcp_started,
 	.this_layer_finished	= ipcp_finished,
+	.rca			= ipcp_rca,
 	.option_scan		= ipcp_option_scan,
 	.option_process		= ipcp_option_process,
 };

gatchat/ppp_lcp.c

@@ -96,6 +96,23 @@ static void lcp_finished(struct pppcp_data *pppcp)
 	ppp_generate_event(pppcp_get_ppp(pppcp), PPP_DOWN);
 }
 
+static void lcp_rca(struct pppcp_data *pppcp, const struct pppcp_packet *packet)
+{
+	struct ppp_option_iter iter;
+
+	ppp_option_iter_init(&iter, packet);
+
+	while (ppp_option_iter_next(&iter) == TRUE) {
+		switch (ppp_option_iter_get_type(&iter)) {
+		case ACCM:
+			ppp_set_xmit_accm(pppcp_get_ppp(pppcp), 0);
+			break;
+		default:
+			break;
+		}
+	}
+}
+
 /*
  * Scan the option to see if it is acceptable, unacceptable, or rejected
  *
@@ -189,6 +206,7 @@ struct pppcp_action lcp_action = {
 	.this_layer_down	= lcp_down,
 	.this_layer_started	= lcp_started,
 	.this_layer_finished	= lcp_finished,
+	.rca			= lcp_rca,
 	.option_scan		= lcp_option_scan,
 	.option_process		= lcp_option_process,
 };