Gave rarpd back the ability to poke temporary entries into the arp

table; arptab.c is really a hacked up version of arp.c that only
supports adding temporary entries. (This stuff is nasty -- I wish I
knew what was so wrong with SIOCSARP/SIOCGARP/etc... that made the
BSD developers decide to take it out.) The idea here is that the
client issuing the rarp is expected to be in the middle of booting
and would therefore be unable to answer arp queries from other machines
on the wire. Having rarpd stuff a temporary entry for the booting
host into the local arp table helps keep arp requests from going unanswered.

Also added ether_print() and ether_ntoa() to the ether_addr.c module.
Eventually I'll get ether_aton() and ether_hostton() written and
then this file can be dropped straight into libc. (Assuming no one
objects, of course. :)

4 files changed, 252 insertions, 8 deletions

diff --git a/usr.sbin/rarpd/Makefile b/usr.sbin/rarpd/Makefile
index 9415fc9..c108d62 100644
--- a/usr.sbin/rarpd/Makefile
+++ b/usr.sbin/rarpd/Makefile
@@ -1,9 +1,9 @@
 #	from: @(#)Makefile	5.8 (Berkeley) 7/28/90
-#	$Id: Makefile,v 1.1 1994/08/08 01:03:57 wollman Exp $
+#	$Id: Makefile,v 1.1.1.1 1995/03/02 06:41:39 wpaul Exp $
 
 PROG=	rarpd
 MAN8=	rarpd.8
-SRCS=	rarpd.c ether_addr.c
+SRCS=	rarpd.c arptab.c ether_addr.c
 CFLAGS+= -DTFTP_DIR=\"/tftpboot\"
 
 .include <bsd.prog.mk>
diff --git a/usr.sbin/rarpd/arptab.c b/usr.sbin/rarpd/arptab.c
new file mode 100644
index 0000000..f1f5cfc
--- /dev/null
+++ b/usr.sbin/rarpd/arptab.c
@@ -0,0 +1,219 @@
+/*
+ * Copyright (c) 1984, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Sun Microsystems, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char copyright[] =
+"@(#) Copyright (c) 1984, 1993\n\
+	The Regents of the University of California.  All rights reserved.\n";
+#endif /* not lint */
+
+#ifndef lint
+static char sccsid[] = "@(#)arp.c	8.2 (Berkeley) 1/2/94";
+#endif /* not lint */
+
+/*
+ * set arp table entries
+ */
+
+
+#include <sys/param.h>
+#include <sys/file.h>
+#include <sys/socket.h>
+#include <sys/sysctl.h>
+
+#include <net/if.h>
+#include <net/if_dl.h>
+#include <net/if_types.h>
+#include <net/route.h>
+
+#include <netinet/in.h>
+#include <netinet/if_ether.h>
+
+#include <arpa/inet.h>
+
+#include <netdb.h>
+#include <errno.h>
+#include <nlist.h>
+#include <stdio.h>
+#include <paths.h>
+#include <syslog.h>
+
+extern int errno;
+static int pid;
+static int s = -1;
+
+getsocket() {
+	if (s < 0) {
+		s = socket(PF_ROUTE, SOCK_RAW, 0);
+		if (s < 0) {
+			perror("arp: socket");
+			exit(1);
+		}
+	}
+}
+
+struct	sockaddr_in so_mask = {8, 0, 0, { 0xffffffff}};
+struct	sockaddr_inarp blank_sin = {sizeof(blank_sin), AF_INET }, sin_m;
+struct	sockaddr_dl blank_sdl = {sizeof(blank_sdl), AF_LINK }, sdl_m;
+int	expire_time, flags, export_only, doing_proxy;
+struct	{
+	struct	rt_msghdr m_rtm;
+	char	m_space[512];
+}	m_rtmsg;
+
+/*
+ * Set an individual arp entry 
+ */
+arptab_set(eaddr, host)
+	u_char *eaddr;
+	u_long host;
+{
+	register struct sockaddr_inarp *sin = &sin_m;
+	register struct sockaddr_dl *sdl;
+	register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm);
+	struct timeval time;
+
+	getsocket();
+	pid = getpid();
+	sdl_m = blank_sdl;
+	sin_m = blank_sin;
+	sin->sin_addr.s_addr = host;
+	bcopy((char *)eaddr, (u_char *)LLADDR(&sdl_m), 6);
+	sdl_m.sdl_alen = 6;
+	doing_proxy = flags = export_only = expire_time = 0;
+	gettimeofday(&time, 0);
+	expire_time = time.tv_sec + 20 * 60;
+
+tryagain:
+	if (rtmsg(RTM_GET) < 0) {
+		syslog(LOG_ERR,"%s: %m", inet_ntoa(sin->sin_addr));
+		return (1);
+	}
+	sin = (struct sockaddr_inarp *)(rtm + 1);
+	sdl = (struct sockaddr_dl *)(sin->sin_len + (char *)sin);
+	if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
+		if (sdl->sdl_family == AF_LINK &&
+		    (rtm->rtm_flags & RTF_LLINFO) &&
+		    !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) {
+		case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023:
+		case IFT_ISO88024: case IFT_ISO88025:
+			goto overwrite;
+		}
+		if (doing_proxy == 0) {
+			syslog(LOG_ERR, "arptab_set: can only proxy for %s\n", inet_ntoa(sin->sin_addr));
+			return (1);
+		}
+		if (sin_m.sin_other & SIN_PROXY) {
+			syslog(LOG_ERR,"arptab_set: proxy entry exists for non 802 device\n");
+			return(1);
+		}
+		sin_m.sin_other = SIN_PROXY;
+		export_only = 1;
+		goto tryagain;
+	}
+overwrite:
+	if (sdl->sdl_family != AF_LINK) {
+		syslog(LOG_ERR,"arptab_set: cannot intuit interface index and type for %s\n", inet_ntoa(sin->sin_addr));
+		return (1);
+	}
+	sdl_m.sdl_type = sdl->sdl_type;
+	sdl_m.sdl_index = sdl->sdl_index;
+	return (rtmsg(RTM_ADD));
+}
+
+rtmsg(cmd)
+{
+	static int seq;
+	int rlen;
+	register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
+	register char *cp = m_rtmsg.m_space;
+	register int l;
+
+	errno = 0;
+	if (cmd == RTM_DELETE)
+		goto doit;
+	bzero((char *)&m_rtmsg, sizeof(m_rtmsg));
+	rtm->rtm_flags = flags;
+	rtm->rtm_version = RTM_VERSION;
+
+	switch (cmd) {
+	default:
+		syslog(LOG_ERR, "arptap_set: internal wrong cmd\n");
+		exit(1);
+	case RTM_ADD:
+		rtm->rtm_addrs |= RTA_GATEWAY;
+		rtm->rtm_rmx.rmx_expire = expire_time;
+		rtm->rtm_inits = RTV_EXPIRE;
+		rtm->rtm_flags |= (RTF_HOST | RTF_STATIC);
+		sin_m.sin_other = 0;
+		if (doing_proxy) {
+			if (export_only)
+				sin_m.sin_other = SIN_PROXY;
+			else {
+				rtm->rtm_addrs |= RTA_NETMASK;
+				rtm->rtm_flags &= ~RTF_HOST;
+			}
+		}
+		/* FALLTHROUGH */
+	case RTM_GET:
+		rtm->rtm_addrs |= RTA_DST;
+	}
+#define NEXTADDR(w, s) \
+	if (rtm->rtm_addrs & (w)) { \
+		bcopy((char *)&s, cp, sizeof(s)); cp += sizeof(s);}
+
+	NEXTADDR(RTA_DST, sin_m);
+	NEXTADDR(RTA_GATEWAY, sdl_m);
+	NEXTADDR(RTA_NETMASK, so_mask);
+
+	rtm->rtm_msglen = cp - (char *)&m_rtmsg;
+doit:
+	l = rtm->rtm_msglen;
+	rtm->rtm_seq = ++seq;
+	rtm->rtm_type = cmd;
+	if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) {
+		if (errno != ESRCH && errno != EEXIST) {
+			syslog(LOG_ERR, "writing to routing socket: %m");
+			return (-1);
+		}
+	}
+	do {
+		l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
+	} while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid));
+	if (l < 0)
+		syslog(LOG_ERR, "arptab_set: read from routing socket: %m");
+	return (0);
+}
diff --git a/usr.sbin/rarpd/ether_addr.c b/usr.sbin/rarpd/ether_addr.c
index 197c157..a2a38b6 100644
--- a/usr.sbin/rarpd/ether_addr.c
+++ b/usr.sbin/rarpd/ether_addr.c
@@ -10,7 +10,7 @@
  *
  * Have a party.
  *
- *	$Id$
+ *	$Id: ether_addr.c,v 1.1.1.1 1995/03/02 06:41:40 wpaul Exp $
  */
 
 
@@ -106,3 +106,25 @@ nomatch:
 
 return (-1);
 }
+
+int ether_print(cp)
+        u_char *cp;
+{
+        printf("%x:%x:%x:%x:%x:%x", cp[0], cp[1], cp[2], cp[3], cp[4], cp[5]);
+}
+
+int ether_aton(a, n)
+        char *a;
+        u_char *n;
+{
+        int i, o[6];
+
+        i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o[0], &o[1], &o[2],
+                                           &o[3], &o[4], &o[5]);
+        if (i != 6) {
+                return (i);
+        }
+        for (i=0; i<6; i++)
+                n[i] = o[i];
+        return (0);
+}
diff --git a/usr.sbin/rarpd/rarpd.c b/usr.sbin/rarpd/rarpd.c
index aa18dd8..0be3e6c 100644
--- a/usr.sbin/rarpd/rarpd.c
+++ b/usr.sbin/rarpd/rarpd.c
@@ -26,7 +26,7 @@ char copyright[] =
 
 #ifndef lint
 static char rcsid[] =
-    "@(#) $Header: rarpd.c,v 1.6 91/01/09 14:47:00 mccanne Exp $ (LBL)";
+    "@(#) $Header: /a/ncvs/src/usr.sbin/rarpd/rarpd.c,v 1.1.1.1 1995/03/02 06:41:39 wpaul Exp $ (LBL)";
 #endif
 
 
@@ -635,7 +635,7 @@ update_arptab(ep, ipaddr)
 	u_char *ep;
 	u_long ipaddr;
 {
-#ifdef SIOCSARP_IS_DEPRECATED_IN_4_4BSD
+#ifdef SIOCSARP
 	int s;
 	struct arpreq request;
 	struct sockaddr_in *sin;
@@ -651,18 +651,21 @@ update_arptab(ep, ipaddr)
 	if (ioctl(s, SIOCSARP, (caddr_t)&request) < 0)
 		syslog(LOG_ERR, "SIOCSARP: %m");
 	(void)close(s);
+#else
+	if (arptab_set(ep, ipaddr) > 0)
+		syslog(LOG_ERR, "couldn't update arp table");
 #endif
 }
 
 /*
  * Build a reverse ARP packet and sent it out on the interface.
- * 'ep' points to a valid REVARP_REQUEST.  The REVARP_REPLY is built 
+ * 'ep' points to a valid ARPOP_REVREQUEST.  The ARPOP_REVREPLY is built 
  * on top of the request, then written to the network.
  *
  * RFC 903 defines the ether_arp fields as follows.  The following comments
  * are taken (more or less) straight from this document.
  *
- * REVARP_REQUEST
+ * ARPOP_REVREQUEST
  *
  * arp_sha is the hardware address of the sender of the packet.
  * arp_spa is undefined.
@@ -672,7 +675,7 @@ update_arptab(ep, ipaddr)
  *   address of the sender.
  * arp_tpa is undefined.
  *
- * REVARP_REPLY
+ * ARPOP_REVREPLY
  *
  * arp_sha is the hardware address of the responder (the sender of the
  *   reply packet).