From 5a44f89625c1a201058ece428162d035b68a928b Mon Sep 17 00:00:00 2001
From: kettenis <kettenis@openbsd.org>
Date: Fri, 13 Jul 2018 08:46:07 +0000
Subject: [PATCH] When we nack a domain service because we don't support the
 requested major version, provide a major version that we do support.

---
 usr.sbin/ldomd/ds.c | 15 +++++++++++----
 usr.sbin/ldomd/ds.h |  4 ++--
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/usr.sbin/ldomd/ds.c b/usr.sbin/ldomd/ds.c
index 38330af281e..2211f358143 100644
--- a/usr.sbin/ldomd/ds.c
+++ b/usr.sbin/ldomd/ds.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ds.c,v 1.7 2018/07/13 07:29:08 kettenis Exp $	*/
+/*	$OpenBSD: ds.c,v 1.8 2018/07/13 08:46:07 kettenis Exp $	*/
 
 /*
  * Copyright (c) 2012 Mark Kettenis
@@ -444,6 +444,7 @@ ds_rx_msg(struct ldc_conn *lc, void *data, size_t len)
 	{
 		struct ds_reg_req *dr = data;
 		struct ds_conn_svc *dcs;
+		uint16_t major = 0;
 
 		DPRINTF(("DS_REG_REQ %s %d.%d 0x%016llx\n", dr->svc_id,
 		    dr->major_vers, dr->minor_vers, dr->svc_handle));
@@ -459,7 +460,13 @@ ds_rx_msg(struct ldc_conn *lc, void *data, size_t len)
 			}
 		}
 
-		ds_reg_nack(lc, dr->svc_handle);
+		TAILQ_FOREACH(dcs, &dc->services, link) {
+			if (strcmp(dr->svc_id, dcs->service->ds_svc_id) == 0 &&
+			    dcs->service->ds_major_vers > major)
+				major = dcs->service->ds_major_vers;
+		}
+
+		ds_reg_nack(lc, dr->svc_handle, major);
 		break;
 	}
 
@@ -521,7 +528,7 @@ ds_reg_ack(struct ldc_conn *lc, uint64_t svc_handle, uint16_t minor)
 }
 
 void
-ds_reg_nack(struct ldc_conn *lc, uint64_t svc_handle)
+ds_reg_nack(struct ldc_conn *lc, uint64_t svc_handle, uint16_t major)
 {
 	struct ds_reg_nack dn;
 
@@ -531,7 +538,7 @@ ds_reg_nack(struct ldc_conn *lc, uint64_t svc_handle)
 	dn.payload_len = sizeof(dn) - 8;
 	dn.svc_handle = svc_handle;
 	dn.result = DS_REG_VER_NACK;
-	dn.major_vers = 0;
+	dn.major_vers = major;
 	ds_send_msg(lc, &dn, sizeof(dn));
 }
 
diff --git a/usr.sbin/ldomd/ds.h b/usr.sbin/ldomd/ds.h
index ab3249a414b..56ab46889de 100644
--- a/usr.sbin/ldomd/ds.h
+++ b/usr.sbin/ldomd/ds.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ds.h,v 1.3 2018/07/13 07:29:08 kettenis Exp $	*/
+/*	$OpenBSD: ds.h,v 1.4 2018/07/13 08:46:07 kettenis Exp $	*/
 
 /*
  * Copyright (c) 2012 Mark Kettenis
@@ -200,7 +200,7 @@ void	ds_rx_msg(struct ldc_conn *, void *, size_t);
 
 void	ds_init_ack(struct ldc_conn *);
 void	ds_reg_ack(struct ldc_conn *, uint64_t, uint16_t);
-void	ds_reg_nack(struct ldc_conn *, uint64_t);
+void	ds_reg_nack(struct ldc_conn *, uint64_t, uint16_t);
 void	ds_unreg_ack(struct ldc_conn *, uint64_t);
 void	ds_unreg_nack(struct ldc_conn *, uint64_t);
 
-- 
2.20.1