From: Daniel Lenski <dlenski@gmail.com>
Date: Sun, 17 May 2020 19:46:43 +0000 (-0700)
Subject: make delay_tunnel consistent with delay_close
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=6dc6c55b639d019ea1478f7563193a1861bdbbe5;p=users%2Fdwmw2%2Fopenconnect.git

make delay_tunnel consistent with delay_close

1. Decrement counter on each mainloop iteration. Protocol needs to keep setting it to get more mainloop iterations before tunnel setup / close.
2. Value ≥2 causes us to set did_work=1, resulting in no delay before we call mainloop again. Protocol should only set this if it needs to SEND something in order to move things along.
3. Value =1 causes us to set did_work=0, resulting in a delay before we call mainloop again. Protocol should only set this if it needs to RECEIVE something in order to move things along.

Also fix values of NCP_TERM_ACK_{SENT,RECEIVED}.

Signed-off-by: Daniel Lenski <dlenski@gmail.com>
---

diff --git a/mainloop.c b/mainloop.c
index b9c8ce29..13d45925 100644
--- a/mainloop.c
+++ b/mainloop.c
@@ -207,9 +207,12 @@ int openconnect_mainloop(struct openconnect_info *vpninfo,
 			timeout = 1000;
 
 		if (!tun_is_up(vpninfo)) {
-			if (vpninfo->delay_tunnel)
+			if (vpninfo->delay_tunnel > 0) {
 				vpn_progress(vpninfo, PRG_DEBUG, _("Delaying tunnel by protocol request.\n"));
-			else if (vpninfo->dtls_state == DTLS_CONNECTING) {
+				/* XX: don't let this spin forever */
+				if (--vpninfo->delay_tunnel > 0)
+					did_work++;
+			} else if (vpninfo->dtls_state == DTLS_CONNECTING) {
 				/* Postpone tun device creation after DTLS is connected so
 				 * we have a better knowledge of the link MTU. We also
 				 * force the creation if DTLS enters sleeping mode - i.e.,
diff --git a/openconnect-internal.h b/openconnect-internal.h
index f36bd61f..055ff6f1 100644
--- a/openconnect-internal.h
+++ b/openconnect-internal.h
@@ -649,8 +649,8 @@ struct openconnect_info {
 #endif
 	int ssl_fd;
 	int dtls_fd;
-	int delay_tunnel;	                /* Delay tunnel setup */
-	int delay_close;	                /* Delay close of mainloop */
+	int delay_tunnel;	                /* Delay tunnel setup (2 for immediate callback, 1 for wait) */
+	int delay_close;	                /* Delay close of mainloop (2 for immediate callback, 1 for wait) */
 
 	int dtls_tos_current;
 	int dtls_pass_tos;
diff --git a/ppp.c b/ppp.c
index 78de5890..5186b1c1 100644
--- a/ppp.c
+++ b/ppp.c
@@ -780,9 +780,6 @@ static int handle_state_transition(struct openconnect_info *vpninfo, int *timeou
 
 	switch (ppp->ppp_state) {
 	case PPPS_DEAD:
-		/* Delay tunnel setup until after PPP negotiation */
-		vpninfo->delay_tunnel = 1;
-
 		/* Prevent race conditions after recovering dead peer connection */
 		vpninfo->ssl_times.last_rx = vpninfo->ssl_times.last_tx = now;
 
@@ -831,8 +828,7 @@ static int handle_state_transition(struct openconnect_info *vpninfo, int *timeou
 			break;
 
 		ppp->ppp_state = PPPS_NETWORK;
-		vpninfo->delay_tunnel = 0; /* tunnel can start now */
-		vpninfo->delay_close = 2;  /* need two mainloop iterations on close (send TERMREQ; receive TERMACK) */
+		vpninfo->delay_close = 2;  /* we will need immediate callback (to send TERMREQ) when local side wants to close */
 		/* fall through */
 
 	case PPPS_NETWORK:
@@ -854,9 +850,10 @@ static int handle_state_transition(struct openconnect_info *vpninfo, int *timeou
 				ppp->lcp.state |= NCP_TERM_REQ_SENT;
 				ppp->lcp.last_req = now;
 				(void) queue_config_packet(vpninfo, PPP_LCP, ++ppp->lcp.id, TERMREQ, 0, NULL);
+				vpninfo->delay_close = 1; /* need to wait until we receive TERMACK */
 			}
 			if (!ka_check_deadline(timeout, now, ppp->lcp.last_req + 3))
-				vpninfo->delay_close = 1;
+				vpninfo->delay_close = 1; /* still waiting to receive TERMACK */
 			else
 				(void) queue_config_packet(vpninfo, PPP_LCP, ++ppp->lcp.id, TERMREQ, 0, NULL);
 		}
@@ -867,6 +864,9 @@ static int handle_state_transition(struct openconnect_info *vpninfo, int *timeou
 		return -EINVAL;
 	}
 
+	/* Delay tunnel setup until after PPP negotiation */
+	vpninfo->delay_tunnel = (ppp->ppp_state == PPPS_NETWORK ? 0 : 1);
+
 	if (last_state != ppp->ppp_state) {
 		vpn_progress(vpninfo, PRG_DEBUG,
 			     _("PPP state transition from %s to %s\n"),
diff --git a/ppp.h b/ppp.h
index 07f2a8f5..2f3ac6f7 100644
--- a/ppp.h
+++ b/ppp.h
@@ -58,8 +58,8 @@
 #define NCP_CONF_ACK_SENT	8
 #define NCP_TERM_REQ_SENT	16
 #define NCP_TERM_REQ_RECEIVED	32
-#define NCP_TERM_ACK_SENT	16
-#define NCP_TERM_ACK_RECEIVED	32
+#define NCP_TERM_ACK_SENT	64
+#define NCP_TERM_ACK_RECEIVED	128
 
 /* RFC1661 (or RFC1662 for ASYNCMAP) */
 #define LCP_MRU			1