packages/net/openconnect/patches/001-always-resolve-ips.patch

diff --git a/cstp.c b/cstp.c
index b1235ef..f955b82 100644
--- a/cstp.c
+++ b/cstp.c
@@ -570,7 +570,10 @@ int openconnect_make_cstp_connection(struct openconnect_info *vpninfo)
 	return ret;
 }
 
-static int cstp_reconnect(struct openconnect_info *vpninfo)
+/* When dead peer is set, this function will re-attempt resolving
+ * the peer in case its IP changed.
+ */
+static int cstp_reconnect(struct openconnect_info *vpninfo, unsigned dead_peer)
 {
 	int ret;
 	int timeout;
@@ -591,6 +594,16 @@ static int cstp_reconnect(struct openconnect_info *vpninfo)
 	timeout = vpninfo->reconnect_timeout;
 	interval = vpninfo->reconnect_interval;
 
+	/* handle cases with dynamic DNS by forcing a new resolve.
+	 * The original IP is saved to retry as fallback if resolving
+	 * fails.
+	 */
+	if (dead_peer && vpninfo->first_peer_addr == NULL) {
+		vpninfo->first_peer_addr = vpninfo->peer_addr;
+		vpninfo->first_peer_addrlen = vpninfo->peer_addrlen;
+		vpninfo->peer_addr = NULL;
+	}
+
 	while ((ret = openconnect_make_cstp_connection(vpninfo))) {
 		if (timeout <= 0)
 			return ret;
@@ -611,6 +624,11 @@ static int cstp_reconnect(struct openconnect_info *vpninfo)
 		interval += vpninfo->reconnect_interval;
 		if (interval > RECONNECT_INTERVAL_MAX)
 			interval = RECONNECT_INTERVAL_MAX;
+
+		if (dead_peer && vpninfo->first_peer_addr != NULL) {
+			free(vpninfo->peer_addr);
+			vpninfo->peer_addr = NULL;
+		}
 	}
 	script_config_tun(vpninfo, "reconnect");
 	return 0;
@@ -903,8 +921,15 @@ int cstp_mainloop(struct openconnect_info *vpninfo, int *timeout)
 		/* Not that this will ever happen; we don't even process
 		   the setting when we're asked for it. */
 		vpn_progress(vpninfo, PRG_INFO, _("CSTP rekey due\n"));
-		if (vpninfo->ssl_times.rekey_method == REKEY_TUNNEL)
-			goto do_reconnect;
+		if (vpninfo->ssl_times.rekey_method == REKEY_TUNNEL) {
+			ret = cstp_reconnect(vpninfo, 0);
+			if (ret) {
+				vpn_progress(vpninfo, PRG_ERR, _("Reconnect failed\n"));
+				vpninfo->quit_reason = "CSTP reconnect failed";
+				return ret;
+			}
+			goto do_dtls_reconnect;
+		}
 		else if (vpninfo->ssl_times.rekey_method == REKEY_SSL) {
 			ret = cstp_handshake(vpninfo, 0);
 			if (ret) {
@@ -922,7 +947,7 @@ int cstp_mainloop(struct openconnect_info *vpninfo, int *timeout)
 		vpn_progress(vpninfo, PRG_ERR,
 			     _("CSTP Dead Peer Detection detected dead peer!\n"));
 	do_reconnect:
-		ret = cstp_reconnect(vpninfo);
+		ret = cstp_reconnect(vpninfo, 1);
 		if (ret) {
 			vpn_progress(vpninfo, PRG_ERR, _("Reconnect failed\n"));
 			vpninfo->quit_reason = "CSTP reconnect failed";
diff --git a/library.c b/library.c
index f5d3dc9..7c8d5ec 100644
--- a/library.c
+++ b/library.c
@@ -178,6 +178,7 @@ void openconnect_vpninfo_free(struct openconnect_info *vpninfo)
 		CloseHandle(vpninfo->dtls_event);
 #endif
 	free(vpninfo->peer_addr);
+	free(vpninfo->first_peer_addr);
 	free_optlist(vpninfo->csd_env);
 	free_optlist(vpninfo->script_env);
 	free_optlist(vpninfo->cookies);
@@ -291,6 +292,8 @@ int openconnect_set_hostname(struct openconnect_info *vpninfo,
 	vpninfo->unique_hostname = NULL;
 	free(vpninfo->peer_addr);
 	vpninfo->peer_addr = NULL;
+	free(vpninfo->first_peer_addr);
+	vpninfo->first_peer_addr = NULL;
 
 	return 0;
 }
diff --git a/openconnect-internal.h b/openconnect-internal.h
index 1bc79e5..cafbb3c 100644
--- a/openconnect-internal.h
+++ b/openconnect-internal.h
@@ -424,6 +424,9 @@ struct openconnect_info {
 	struct sockaddr *peer_addr;
 	struct sockaddr *dtls_addr;
 
+	struct sockaddr *first_peer_addr;
+	socklen_t first_peer_addrlen;
+
 	int dtls_local_port;
 
 	int deflate;
diff --git a/ssl.c b/ssl.c
index b50652d..e341871 100644
--- a/ssl.c
+++ b/ssl.c
@@ -110,6 +110,7 @@ int connect_https_socket(struct openconnect_info *vpninfo)
 {
 	int ssl_sock = -1;
 	int err;
+	unsigned retry_old_ip = 0;
 
 	if (!vpninfo->port)
 		vpninfo->port = 443;
@@ -230,6 +231,8 @@ int connect_https_socket(struct openconnect_info *vpninfo)
 			if (hints.ai_flags & AI_NUMERICHOST)
 				free(hostname);
 			ssl_sock = -EINVAL;
+			if (vpninfo->first_peer_addr != NULL)
+				retry_old_ip = 1;
 			goto out;
 		}
 		if (hints.ai_flags & AI_NUMERICHOST)
@@ -291,7 +294,10 @@ int connect_https_socket(struct openconnect_info *vpninfo)
 		}
 		freeaddrinfo(result);
 
+
 		if (ssl_sock < 0) {
+			if (vpninfo->first_peer_addr != NULL)
+				retry_old_ip = 1;
 			vpn_progress(vpninfo, PRG_ERR,
 				     _("Failed to connect to host %s\n"),
 				     vpninfo->proxy?:vpninfo->hostname);
@@ -314,6 +320,21 @@ int connect_https_socket(struct openconnect_info *vpninfo)
 		}
 	}
  out:
+	if (retry_old_ip != 0 && vpninfo->first_peer_addr != NULL) {
+		vpn_progress(vpninfo, PRG_ERR,
+			     _("Retrying connection to host %s with original IP\n"),
+				     vpninfo->proxy?:vpninfo->hostname);
+
+		retry_old_ip = 0;
+		if (vpninfo->first_peer_addrlen > vpninfo->peer_addrlen || vpninfo->peer_addr == NULL)
+			realloc_inplace(vpninfo->peer_addr, vpninfo->first_peer_addrlen);
+
+		if (vpninfo->peer_addr != NULL) {
+			memcpy(vpninfo->peer_addr, vpninfo->first_peer_addr, vpninfo->first_peer_addrlen);
+			goto reconnect;
+		}
+	}
+
 	/* If proxy processing returned -EAGAIN to reconnect before attempting
 	   further auth, and we failed to reconnect, we have to clean up here. */
 	cleanup_proxy_auth(vpninfo);