From: Joseph C. Lehner <joseph.c.lehner@gmail.com>
Date: Sun, 1 Mar 2020 21:32:26 +0000 (+0100)
Subject: Fix mac handling in blind mode
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=4c376a76f86779b7f8e98871f9a864fc8aea2b60;p=oweals%2Fnmrpflash.git

Fix mac handling in blind mode
---

diff --git a/nmrp.c b/nmrp.c
index 1f17fd8..d85d5ae 100644
--- a/nmrp.c
+++ b/nmrp.c
@@ -492,8 +492,6 @@ int nmrp_do(struct nmrpd_args *args)
 		status = pkt_recv(sock, &rx);
 		if (status == 0) {
 			if (memcmp(rx.eh.ether_dhost, src, 6) == 0) {
-				// set the destination MAC for all subsequent packages
-				memcpy(tx.eh.ether_dhost, rx.eh.ether_shost, 6);
 				break;
 			} else if (verbosity) {
 				printf("\nIgnoring bogus response: %s -> %s.\n",
@@ -512,7 +510,7 @@ int nmrp_do(struct nmrpd_args *args)
 					goto out;
 				} else {
 					// we're blind, so fake a response from the MAC specified by -m
-					memcpy(rx.eh.ether_dhost, dest, 6);
+					memcpy(rx.eh.ether_shost, dest, 6);
 					msg_init(&rx.msg, NMRP_C_CONF_REQ);
 					printf("Faking one.");
 					break;
@@ -523,6 +521,8 @@ int nmrp_do(struct nmrpd_args *args)
 
 	printf("\n");
 
+	memcpy(tx.eh.ether_dhost, rx.eh.ether_shost, 6);
+
 	if (ethsock_arp_add(sock, rx.eh.ether_shost, ipaddr.s_addr, &arp_undo) != 0) {
 		goto out;
 	}