From 35f7e862b336c6e78ca8e88fb9646edddd191065 Mon Sep 17 00:00:00 2001
From: claudio <claudio@openbsd.org>
Date: Mon, 26 Jun 2023 10:08:56 +0000
Subject: [PATCH] Update and refactor dvrmpd to use the new ibu API.

Do the checksum calculation in send_packet() instead of doing it all over
the place. This way the fixup only happens in one place.
OK tb@
---
 usr.sbin/dvmrpd/ask_nbrs2.c |  9 ++-------
 usr.sbin/dvmrpd/dvmrpe.h    |  5 +++--
 usr.sbin/dvmrpd/graft.c     |  9 ++-------
 usr.sbin/dvmrpd/graft_ack.c |  9 ++-------
 usr.sbin/dvmrpd/igmp.c      |  7 ++-----
 usr.sbin/dvmrpd/nbrs2.c     |  9 ++-------
 usr.sbin/dvmrpd/packet.c    | 17 ++++++++++++++---
 usr.sbin/dvmrpd/probe.c     |  9 ++-------
 usr.sbin/dvmrpd/prune.c     |  9 ++-------
 usr.sbin/dvmrpd/report.c    | 13 ++++---------
 10 files changed, 35 insertions(+), 61 deletions(-)

diff --git a/usr.sbin/dvmrpd/ask_nbrs2.c b/usr.sbin/dvmrpd/ask_nbrs2.c
index 608f289f543..40b730b2ed2 100644
--- a/usr.sbin/dvmrpd/ask_nbrs2.c
+++ b/usr.sbin/dvmrpd/ask_nbrs2.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ask_nbrs2.c,v 1.5 2015/12/07 19:17:18 mmcc Exp $ */
+/*	$OpenBSD: ask_nbrs2.c,v 1.6 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2006 Esben Norby <norby@openbsd.org>
@@ -36,7 +36,6 @@ send_ask_nbrs2(struct iface *iface, struct in_addr addr, void *data, int len)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	int			 ret = 0;
 
 	log_debug("send_ask_nbrs2: interface %s addr %s",
@@ -56,11 +55,7 @@ send_ask_nbrs2(struct iface *iface, struct in_addr addr, void *data, int len)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	dst.sin_addr.s_addr = addr.s_addr;
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 fail:
diff --git a/usr.sbin/dvmrpd/dvmrpe.h b/usr.sbin/dvmrpd/dvmrpe.h
index 535c29b5577..ffba1ca5595 100644
--- a/usr.sbin/dvmrpd/dvmrpe.h
+++ b/usr.sbin/dvmrpd/dvmrpe.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dvmrpe.h,v 1.7 2021/01/19 12:23:30 claudio Exp $ */
+/*	$OpenBSD: dvmrpe.h,v 1.8 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2004, 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -183,7 +183,8 @@ struct ctl_nbr	*nbr_to_ctl(struct nbr *);
 
 /* packet.c */
 int		 gen_dvmrp_hdr(struct ibuf *, struct iface *, u_int8_t);
-int		 send_packet(struct iface *, void *, size_t, struct sockaddr_in *);
+int		 send_packet(struct iface *, struct ibuf *,
+		     struct sockaddr_in *);
 void		 recv_packet(int, short, void *);
 
 /* probe.c */
diff --git a/usr.sbin/dvmrpd/graft.c b/usr.sbin/dvmrpd/graft.c
index 4340f6b0628..4545176a23f 100644
--- a/usr.sbin/dvmrpd/graft.c
+++ b/usr.sbin/dvmrpd/graft.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: graft.c,v 1.5 2015/12/07 19:17:18 mmcc Exp $ */
+/*	$OpenBSD: graft.c,v 1.6 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -36,7 +36,6 @@ send_graft(struct iface *iface, struct in_addr addr, void *data, int len)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	int			 ret = 0;
 
 	log_debug("send_graft: interface %s addr %s",
@@ -56,11 +55,7 @@ send_graft(struct iface *iface, struct in_addr addr, void *data, int len)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	dst.sin_addr.s_addr = addr.s_addr;
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 fail:
diff --git a/usr.sbin/dvmrpd/graft_ack.c b/usr.sbin/dvmrpd/graft_ack.c
index 364fac101c8..c609c855506 100644
--- a/usr.sbin/dvmrpd/graft_ack.c
+++ b/usr.sbin/dvmrpd/graft_ack.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: graft_ack.c,v 1.5 2015/12/07 19:17:18 mmcc Exp $ */
+/*	$OpenBSD: graft_ack.c,v 1.6 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2006 Esben Norby <norby@openbsd.org>
@@ -36,7 +36,6 @@ send_graft_ack(struct iface *iface, struct in_addr addr, void *data, int len)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	int			 ret = 0;
 
 	log_debug("send_graft_ack: interface %s addr %s",
@@ -56,11 +55,7 @@ send_graft_ack(struct iface *iface, struct in_addr addr, void *data, int len)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	dst.sin_addr.s_addr = addr.s_addr;
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 fail:
diff --git a/usr.sbin/dvmrpd/igmp.c b/usr.sbin/dvmrpd/igmp.c
index 90196710250..c1c2b93c10d 100644
--- a/usr.sbin/dvmrpd/igmp.c
+++ b/usr.sbin/dvmrpd/igmp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: igmp.c,v 1.4 2015/12/07 19:14:49 mmcc Exp $ */
+/*	$OpenBSD: igmp.c,v 1.5 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -73,9 +73,6 @@ send_igmp_query(struct iface *iface, struct group *group)
 		igmp_hdr.max_resp_time = iface->last_member_query_interval;
 	}
 
-	/* update chksum */
-	igmp_hdr.chksum = in_cksum(&igmp_hdr, sizeof(igmp_hdr));
-
 	ibuf_add(buf, &igmp_hdr, sizeof(igmp_hdr));
 
 	/* set destination address */
@@ -83,7 +80,7 @@ send_igmp_query(struct iface *iface, struct group *group)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	inet_aton(AllSystems, &dst.sin_addr);
 
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 }
diff --git a/usr.sbin/dvmrpd/nbrs2.c b/usr.sbin/dvmrpd/nbrs2.c
index 5217bb03a11..0e362ebf4b7 100644
--- a/usr.sbin/dvmrpd/nbrs2.c
+++ b/usr.sbin/dvmrpd/nbrs2.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nbrs2.c,v 1.4 2015/05/05 01:26:37 jsg Exp $ */
+/*	$OpenBSD: nbrs2.c,v 1.5 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2006 Esben Norby <norby@openbsd.org>
@@ -37,7 +37,6 @@ send_nbrs2(struct iface *iface, struct in_addr addr, void *data, int len)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	int			 ret = 0;
 
 	log_debug("send_nbrs2: interface %s addr %s",
@@ -57,11 +56,7 @@ send_nbrs2(struct iface *iface, struct in_addr addr, void *data, int len)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	dst.sin_addr.s_addr = addr.s_addr;
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 fail:
diff --git a/usr.sbin/dvmrpd/packet.c b/usr.sbin/dvmrpd/packet.c
index 0a7dd6d7a3b..f0b22d6eff9 100644
--- a/usr.sbin/dvmrpd/packet.c
+++ b/usr.sbin/dvmrpd/packet.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: packet.c,v 1.7 2021/01/19 16:02:56 claudio Exp $ */
+/*	$OpenBSD: packet.c,v 1.8 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2004, 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -27,6 +27,7 @@
 
 #include <errno.h>
 #include <event.h>
+#include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -61,8 +62,10 @@ gen_dvmrp_hdr(struct ibuf *buf, struct iface *iface, u_int8_t code)
 
 /* send and receive packets */
 int
-send_packet(struct iface *iface, void *pkt, size_t len, struct sockaddr_in *dst)
+send_packet(struct iface *iface, struct ibuf *pkt, struct sockaddr_in *dst)
 {
+	u_int16_t	chksum;
+
 	if (iface->passive) {
 		log_warnx("send_packet: cannot send packet on passive "
 		    "interface %s", iface->name);
@@ -77,7 +80,15 @@ send_packet(struct iface *iface, void *pkt, size_t len, struct sockaddr_in *dst)
 			return (-1);
 		}
 
-	if (sendto(iface->fd, pkt, len, 0,
+	/* update chksum */
+	chksum = in_cksum(ibuf_data(pkt), ibuf_size(pkt));
+	if (ibuf_set(pkt, offsetof(struct dvmrp_hdr, chksum),
+	    &chksum, sizeof(chksum)) == -1) {
+		log_warn("send_packet: failed to update checksum");
+		return (-1);
+	}
+
+	if (sendto(iface->fd, ibuf_data(pkt), ibuf_size(pkt), 0,
 	    (struct sockaddr *)dst, sizeof(*dst)) == -1 ) {
 		log_warn("send_packet: error sending packet on interface %s",
 		    iface->name);
diff --git a/usr.sbin/dvmrpd/probe.c b/usr.sbin/dvmrpd/probe.c
index 0a6e02f31a5..98b803c8d4c 100644
--- a/usr.sbin/dvmrpd/probe.c
+++ b/usr.sbin/dvmrpd/probe.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: probe.c,v 1.4 2015/05/05 01:26:37 jsg Exp $ */
+/*	$OpenBSD: probe.c,v 1.5 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -39,7 +39,6 @@ send_probe(struct iface *iface)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	struct nbr		*nbr;
 	int			 ret = 0;
 
@@ -67,11 +66,7 @@ send_probe(struct iface *iface)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	inet_aton(AllDVMRPRouters, &dst.sin_addr);
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 fail:
diff --git a/usr.sbin/dvmrpd/prune.c b/usr.sbin/dvmrpd/prune.c
index ef9355c3ea9..c7c4ff64d55 100644
--- a/usr.sbin/dvmrpd/prune.c
+++ b/usr.sbin/dvmrpd/prune.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: prune.c,v 1.6 2015/12/07 19:14:49 mmcc Exp $ */
+/*	$OpenBSD: prune.c,v 1.7 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -37,7 +37,6 @@ send_prune(struct nbr *nbr, struct prune *p)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	struct prune_hdr	 prune;
 	int			 ret = 0;
 
@@ -69,11 +68,7 @@ send_prune(struct nbr *nbr, struct prune *p)
 
 	ibuf_add(buf, &prune, sizeof(prune));
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(nbr->iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(nbr->iface, buf, &dst);
 	ibuf_free(buf);
 
 	return (ret);
diff --git a/usr.sbin/dvmrpd/report.c b/usr.sbin/dvmrpd/report.c
index b56cda5132d..cc8ed3a3c07 100644
--- a/usr.sbin/dvmrpd/report.c
+++ b/usr.sbin/dvmrpd/report.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: report.c,v 1.11 2015/12/07 18:59:31 mmcc Exp $ */
+/*	$OpenBSD: report.c,v 1.12 2023/06/26 10:08:56 claudio Exp $ */
 
 /*
  * Copyright (c) 2005, 2006 Esben Norby <norby@openbsd.org>
@@ -41,7 +41,6 @@ send_report(struct iface *iface, struct in_addr addr, void *data, int len)
 {
 	struct sockaddr_in	 dst;
 	struct ibuf		*buf;
-	struct dvmrp_hdr	*dvmrp_hdr;
 	int			 ret = 0;
 
 	log_debug("send_report: interface %s addr %s",
@@ -63,11 +62,7 @@ send_report(struct iface *iface, struct in_addr addr, void *data, int len)
 	dst.sin_len = sizeof(struct sockaddr_in);
 	dst.sin_addr.s_addr = addr.s_addr;
 
-	/* update chksum */
-	dvmrp_hdr = ibuf_seek(buf, 0, sizeof(*dvmrp_hdr));
-	dvmrp_hdr->chksum = in_cksum(buf->buf, buf->wpos);
-
-	ret = send_packet(iface, buf->buf, buf->wpos, &dst);
+	ret = send_packet(iface, buf, &dst);
 	ibuf_free(buf);
 	return (ret);
 fail:
@@ -247,7 +242,7 @@ rr_list_send(struct rr_head *rr_list, struct iface *xiface, struct nbr *nbr)
 
 		prefixlen = 0;
 		while (((le = TAILQ_FIRST(rr_list)) != NULL) &&
-		    (buf->wpos < 1000)) {
+		    (ibuf_size(buf) < 1000)) {
 			/* netmask */
 			netmask = le->re->mask.s_addr;
 			if (prefixlen != mask2prefixlen(netmask)) {
@@ -288,7 +283,7 @@ rr_list_send(struct rr_head *rr_list, struct iface *xiface, struct nbr *nbr)
 			rr_list_remove(le->re);
 			free(le);
 		}
-		send_report(iface, addr, buf->buf, buf->wpos);
+		send_report(iface, addr, ibuf_data(buf), ibuf_size(buf));
 		ibuf_free(buf);
 	}
 }
-- 
2.20.1