Merge branch 'tmp-fix-anyconnect-disconnect' into 'master'

Distinguish the bye packet interpretation

Closes #281

See merge request openconnect/ocserv!162

src/common/common.c

@@ -170,6 +170,8 @@ const char *discon_reason_to_str(unsigned reason)
 		return "unspecified";
 	case REASON_USER_DISCONNECT:
 		return "user disconnected";
+	case REASON_TEMP_DISCONNECT:
+		return "anyconnect client disconnected";
 	case REASON_SERVER_DISCONNECT:
 		return "server disconnected";
 	case REASON_IDLE_TIMEOUT:

src/defs.h

@@ -37,6 +37,7 @@
 #define REASON_DPD_TIMEOUT 5
 #define REASON_ERROR 6
 #define REASON_SESSION_TIMEOUT 7
+#define REASON_TEMP_DISCONNECT 8
 
 /* Timeout (secs) for communication between main and sec-mod */
 #define MAIN_SEC_MOD_TIMEOUT 120

src/worker-vpn.c

@@ -2514,7 +2514,21 @@ static int parse_data(struct worker_st *ws, uint8_t *buf, size_t buf_size,
 		break;
 	case AC_PKT_DISCONN:
 		oclog(ws, LOG_INFO, "received BYE packet; exiting");
-		exit_worker_reason(ws, REASON_USER_DISCONNECT);
+		/* In openconnect the BYE packet indicates an explicit
+		 * user disconnect. In anyconnect clients it may indicate
+		 * an intention to reconnect (e.g., because network was
+		 * changed). We separate the error codes to ensure we do
+		 * do not interpret the intention incorrectly (see #281). */
+		if (plain_size > 0 && plain[0] == 0xb0) {
+			exit_worker_reason(ws, REASON_USER_DISCONNECT);
+		} else {
+			if (plain_size > 0) {
+				oclog(ws, LOG_DEBUG, "bye packet with payload: %u/%.2x", (unsigned)plain_size, plain[0]);
+				return -1;
+			}
+
+			exit_worker_reason(ws, REASON_TEMP_DISCONNECT);
+		}
 		break;
 	case AC_PKT_COMPRESSED:
 		/* decompress */