Add a new 'nameserver' command to route(8).

It sends nameserver proposals to resolvd(8) using the dns proposal
protocol over the route socket. Based on a seperate program
written by florian@. deraadt noticed some whitespace issues.
more fixes and ok florian@

4 files changed, 174 insertions, 7 deletions

diff --git a/sbin/route/keywords.h b/sbin/route/keywords.h
index 0fd50932596..eb2901f9e21 100644
--- a/sbin/route/keywords.h
+++ b/sbin/route/keywords.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: keywords.h,v 1.35 2020/10/29 21:15:26 denis Exp $ */
+/* $OpenBSD: keywords.h,v 1.36 2021/08/04 18:17:23 benno Exp $ */
 
 /* WARNING!  This file was generated by keywords.sh  */
 
@@ -45,6 +45,7 @@ enum {
 	K_MPLS,
 	K_MPLSLABEL,
 	K_MTU,
+	K_NAMESERVER,
 	K_NET,
 	K_NETMASK,
 	K_NOBFD,
@@ -109,6 +110,7 @@ struct keytab keywords[] = {
 	{ "mpls",	K_MPLS },
 	{ "mplslabel",	K_MPLSLABEL },
 	{ "mtu",	K_MTU },
+	{ "nameserver",	K_NAMESERVER },
 	{ "net",	K_NET },
 	{ "netmask",	K_NETMASK },
 	{ "nobfd",	K_NOBFD },
@@ -135,4 +137,3 @@ struct keytab keywords[] = {
 	{ "static",	K_STATIC },
 	{ "swap",	K_SWAP },
 };
-
diff --git a/sbin/route/keywords.sh b/sbin/route/keywords.sh
index 369f1b08aaa..6f9f5a21e4d 100644
--- a/sbin/route/keywords.sh
+++ b/sbin/route/keywords.sh
@@ -1,5 +1,5 @@
 #!/bin/sh
-# $OpenBSD: keywords.sh,v 1.33 2020/10/29 21:15:26 denis Exp $
+# $OpenBSD: keywords.sh,v 1.34 2021/08/04 18:17:23 benno Exp $
 # $NetBSD: keywords.sh,v 1.2 1996/11/15 18:57:21 gwr Exp $
 # @(#)keywords	8.2 (Berkeley) 3/19/94
 #
@@ -46,6 +46,7 @@ mpath
 mpls
 mplslabel
 mtu
+nameserver
 net
 netmask
 nobfd
diff --git a/sbin/route/route.8 b/sbin/route/route.8
index 83e48ec883d..3624e4eaf18 100644
--- a/sbin/route/route.8
+++ b/sbin/route/route.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: route.8,v 1.95 2021/01/02 15:35:24 schwarze Exp $
+.\"	$OpenBSD: route.8,v 1.96 2021/08/04 18:17:23 benno Exp $
 .\"	$NetBSD: route.8,v 1.6 1995/03/18 15:00:13 cgd Exp $
 .\"
 .\" Copyright (c) 1983, 1991, 1993
@@ -30,7 +30,7 @@
 .\"
 .\"	@(#)route.8	8.3 (Berkeley) 3/19/94
 .\"
-.Dd $Mdocdate: January 2 2021 $
+.Dd $Mdocdate: August 4 2021 $
 .Dt ROUTE 8
 .Os
 .Sh NAME
@@ -215,7 +215,6 @@ priority are shown.
 .Fl ifp
 .Ar interface
 .Xc
-.Pp
 Set the preferred source address.
 If
 .Ar address
@@ -237,6 +236,26 @@ destination is on-link
 source address is assigned to a disabled interface
 .El
 .El
+.Bl -tag -width Fl -compact
+.It Xo
+.Ic route
+.Op Fl dtv
+.Op Fl T Ar rtable
+.Tg
+.Cm nameserver
+.Op Ar address
+.Op Ar ...
+.Xc
+Send a list of up to five nameserver addresses proposals to
+.Xr resolvd 8 .
+.Xr resolvd 8
+will react upon this request by writing the nameservers to
+.Pa /etc/resolv.conf .
+If no
+.Ar address
+argument is given, a request to remove the nameservers previously entered for
+the given interface is sent.
+.El
 .Pp
 .Tg destination
 .Tg gateway
@@ -603,9 +622,11 @@ to create the new entry.
 .Xr route 4 ,
 .Xr tcp 4 ,
 .Xr hosts 5 ,
+.Xr resolv.conf 5 ,
 .Xr mygate 5 ,
 .Xr bgpd 8 ,
 .Xr ospfd 8 ,
+.Xr resolvd 8 ,
 .Xr ripd 8 ,
 .Xr sysctl 8
 .Sh HISTORY
diff --git a/sbin/route/route.c b/sbin/route/route.c
index 8af7c93dc9e..376fb37f74d 100644
--- a/sbin/route/route.c
+++ b/sbin/route/route.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.c,v 1.255 2021/06/26 15:42:58 deraadt Exp $	*/
+/*	$OpenBSD: route.c,v 1.256 2021/08/04 18:17:23 benno Exp $	*/
 /*	$NetBSD: route.c,v 1.16 1996/04/15 18:27:05 cgd Exp $	*/
 
 /*
@@ -93,6 +93,7 @@ int	 show(int, char *[]);
 int	 keycmp(const void *, const void *);
 int	 keyword(char *);
 void	 monitor(int, char *[]);
+int	 nameserver(int, char **);
 int	 prefixlen(int, char *);
 void	 sockaddr(char *, struct sockaddr *);
 void	 sodump(sup, char *);
@@ -282,6 +283,9 @@ main(int argc, char **argv)
 	case K_MONITOR:
 		monitor(argc, argv);
 		break;
+	case K_NAMESERVER:
+		rval = nameserver(argc, argv);
+		break;
 	default:
 		usage(*argv);
 		/* NOTREACHED */
@@ -1129,6 +1133,146 @@ monitor(int argc, char *argv[])
 	}
 }
 
+
+int
+nameserver(int argc, char *argv[])
+{
+	struct rt_msghdr         rtm;
+	struct sockaddr_rtdns    rtdns;
+	struct iovec             iov[3];
+	struct addrinfo	 hints, *res;
+	struct in_addr           ns4[5];
+	struct in6_addr          ns6[5];
+	size_t			 ns4_count = 0, ns6_count = 0;
+	long			 pad = 0;
+	unsigned int		 if_index;
+	int			 error = 0, iovcnt = 0, padlen, i;
+	char			*if_name, buf[INET6_ADDRSTRLEN];
+
+
+	argc--;
+	argv++;
+	if (argc == 0)
+		usage(NULL);
+
+	if_name = *argv;
+	argc--;
+	argv++;
+
+	if ((if_index = if_nametoindex(if_name)) == 0)
+		errx(1, "unknown interface: %s", if_name);
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV;
+
+#ifndef nitems
+#define nitems(_a)      (sizeof((_a)) / sizeof((_a)[0]))
+#endif
+
+	for (; argc > 0; argc--, argv++) {
+		error = getaddrinfo(*argv, NULL, &hints, &res);
+		if (error) {
+			errx(1, "%s", gai_strerror(error));
+		}
+		if (res == NULL) {
+			errx(1, "%s: unknown", *argv);
+		}
+
+		switch (res->ai_addr->sa_family) {
+		case AF_INET:
+			if (ns4_count >= nitems(ns4)) {
+				warnx("ignoring superflous nameserver: %s",
+				    *argv);
+				break;
+			}
+			memcpy(&ns4[ns4_count++],
+			    &((struct sockaddr_in *)res->ai_addr)->sin_addr,
+			    sizeof(struct in_addr));
+			break;
+		case AF_INET6:
+			if (ns6_count >= nitems(ns6)) {
+				warnx("ignoring superflous nameserver: %s",
+				    *argv);
+				break;
+			}
+			memcpy(&ns6[ns6_count++],
+			    &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr,
+			    sizeof(struct in6_addr));
+			break;
+		default:
+			errx(1, "unknown address family");
+		}
+		freeaddrinfo(res);
+	}
+
+	if (argc > 0)
+		warnx("ignoring additional nameservers");
+
+	if (verbose) {
+		for (i = 0; i < ns4_count; i++)
+			warnx("v4: %s", inet_ntop(AF_INET, &ns4[i], buf,
+			    sizeof(buf)));
+		for (i = 0; i < ns6_count; i++)
+			warnx("v6: %s", inet_ntop(AF_INET6, &ns6[i], buf,
+			    sizeof(buf)));
+	}
+
+	memset(&rtm, 0, sizeof(rtm));
+
+	rtm.rtm_version = RTM_VERSION;
+	rtm.rtm_type = RTM_PROPOSAL;
+	rtm.rtm_msglen = sizeof(rtm);
+	rtm.rtm_tableid = tableid;
+	rtm.rtm_index = if_index;
+	rtm.rtm_seq = 1;
+	rtm.rtm_priority = RTP_PROPOSAL_STATIC;
+	rtm.rtm_addrs = RTA_DNS;
+	rtm.rtm_flags = RTF_UP;
+
+	iov[iovcnt].iov_base = &rtm;
+	iov[iovcnt++].iov_len = sizeof(rtm);
+
+	iov[iovcnt].iov_base = &rtdns;
+	iov[iovcnt++].iov_len = sizeof(rtdns);
+	rtm.rtm_msglen += sizeof(rtdns);
+
+	padlen = ROUNDUP(sizeof(rtdns)) - sizeof(rtdns);
+	if (padlen > 0) {
+		iov[iovcnt].iov_base = &pad;
+		iov[iovcnt++].iov_len = padlen;
+		rtm.rtm_msglen += padlen;
+	}
+
+	memset(&rtdns, 0, sizeof(rtdns));
+	rtdns.sr_family = AF_INET;
+	rtdns.sr_len = 2 + ns4_count * sizeof(struct in_addr);
+	memcpy(rtdns.sr_dns, ns4, rtdns.sr_len - 2);
+
+	if (debugonly)
+		return (0);
+
+	if (writev(s, iov, iovcnt) == -1) {
+		warn("failed to send route message");
+		error = 1;
+	}
+
+	rtm.rtm_seq++;
+
+	memset(&rtdns, 0, sizeof(rtdns));
+	rtdns.sr_family = AF_INET6;
+	rtdns.sr_len = 2 + ns6_count * sizeof(struct in6_addr);
+	memcpy(rtdns.sr_dns, ns6, rtdns.sr_len - 2);
+
+	if (writev(s, iov, iovcnt) == -1) {
+		warn("failed to send route message");
+		error = 1;
+	}
+
+	return (error);
+}
+
 struct {
 	struct rt_msghdr	m_rtm;
 	char			m_space[512];