1 files changed, 108 insertions, 0 deletions
diff --git a/usr.sbin/rarpd/ether_addr.c b/usr.sbin/rarpd/ether_addr.c
new file mode 100644
index 000000000000..197c15715562
--- /dev/null
+++ b/usr.sbin/rarpd/ether_addr.c
@@ -0,0 +1,108 @@
+/*
+ * rarpd support routines
+ *
+ * Written by Bill Paul <wpaul@ctr.columbia.edu>
+ * Center for Telecommunications Research
+ * Columbia University, New York City
+ *
+ * This code is public domain. There is no copyright. There are no
+ * distribution or usage restrictions. There are no strings attached.
+ *
+ * Have a party.
+ *
+ *	$Id$
+ */
+
+
+#include <stdio.h>
+
+#ifndef _PATH_ETHERS
+#define _PATH_ETHERS "/etc/ethers"
+#endif
+
+/*
+ * This should be defined in <netinet/if_ether.h> but it isn't.
+ */
+struct ether_addr {
+	unsigned char octet[6];
+};
+
+/*
+ * Parse a string of text containing an ethernet address and hostname
+ * and separate it into its component parts.
+ */
+int ether_line(l, e, hostname)
+        char *l;
+	struct ether_addr *e;
+	char *hostname;
+{
+        int i, o[6];
+
+        i = sscanf(l, "%x:%x:%x:%x:%x:%x %s", &o[0], &o[1], &o[2],
+                                              &o[3], &o[4], &o[5],
+					      hostname);
+	if (i != 7)
+                return (-1);
+
+        for (i=0; i<6; i++)
+                e->octet[i] = o[i];
+        return (0);
+}
+
+/*
+ * Map an ethernet address to a hostname. Use either /etc/ethers or
+ * NIS/YP.
+ */
+
+int ether_ntohost(hostname, e)
+	char *hostname;
+	struct ether_addr *e;
+{
+	FILE *fp;
+	static char buf[BUFSIZ];
+	static struct ether_addr local_ether;
+	static char *local_host;
+	static char *result;
+	int resultlen, i;
+	extern int yp_get_default_domain();
+	extern int yp_match();
+	static char *yp_domain;
+	static char ether_a[BUFSIZ];
+
+	if ((fp = fopen(_PATH_ETHERS, "r")) == NULL) {
+                        perror(_PATH_ETHERS);
+                        return (-1);
+	}
+
+	while (fgets(buf,BUFSIZ,fp)) {
+		if (buf[0] == '+') {
+			if (yp_get_default_domain(&yp_domain))
+				return(-1);
+			sprintf(ether_a,"%x:%x:%x:%x:%x:%x",
+						e->octet[0], e->octet[1],
+						e->octet[2], e->octet[3],
+						e->octet[4], e->octet[5]);
+			if (yp_match(yp_domain, "ethers.byaddr", ether_a,
+				strlen(ether_a),&result, &resultlen))
+				return(-1);
+			if (ether_line(result, &local_ether,
+					&local_host) == 0) {
+				strcpy(hostname, (char *)&local_host);
+				return(0);
+			} else
+				return(-1);
+		}
+		if (ether_line(&buf, &local_ether, &local_host) == 0) {
+			for (i = 0; i < 6; i++)
+				if (local_ether.octet[i] != e->octet[i])
+					goto nomatch;
+			/* We have a match */
+			strcpy(hostname, (char *)&local_host);
+			fclose(fp);
+			return(0);
+		}
+nomatch:
+	}
+
+return (-1);
+}