From: Harlan Stenn <stenn@ntp.org>
Date: Thu, 28 Dec 2017 08:09:57 +0000 (-0800)
Subject: sntp: show the IP of who sent us a crypto-NAK
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e5f2cdf71b5c0931f2666c2d5f2251af3e0efe54;p=thirdparty%2Fntp.git

sntp: show the IP of who sent us a crypto-NAK

bk: 5a44a6d5XmukqsFIdOuFFkJIAeTt4A
---

diff --git a/ChangeLog b/ChangeLog
index 25979eac3..6aa156f96 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -64,6 +64,7 @@
 * update-leap: updates from Paul McMath.
 * When using pkg-config, report --modversion.  HStenn.
 * Clean up libevent configure checks.  HStenn.
+* sntp: show the IP of who sent us a crypto-NAK.  HStenn.
 
 ---
 (4.2.8p10) 2017/03/21 Released by Harlan Stenn <stenn@ntp.org>
diff --git a/sntp/networking.c b/sntp/networking.c
index 21cf09a86..ecac15c26 100644
--- a/sntp/networking.c
+++ b/sntp/networking.c
@@ -135,6 +135,8 @@ process_pkt (
 			func_name, pkt_len);
 		return PACKET_UNUSEABLE;
 	}
+
+	/* HMS: the following needs a bit of work */
 	/* Note: pkt_len must be a multiple of 4 at this point! */
 	packet_end = (void*)((char*)rpkt + pkt_len);
 	exten_end = skip_efields(rpkt->exten, packet_end);
@@ -144,18 +146,20 @@ process_pkt (
 			func_name);
 		return PACKET_UNUSEABLE;
 	}
+
 	/* get size of MAC in cells; can be zero */
 	exten_len = (u_int)(packet_end - exten_end);
 
 	/* deduce action required from remaining length */
 	switch (exten_len) {
 
-	case 0:	/* no MAC at all */
+	case 0:	/* no Legacy MAC */
 		break;
 
 	case 1:	/* crypto NAK */		
+		/* Only if the keyID is 0 and there were no EFs */
 		key_id = ntohl(*exten_end);
-		printf("Crypto NAK = 0x%08x\n", key_id);
+		printf("Crypto NAK = 0x%08x from %s\n", key_id, stoa(sender));
 		break;
 
 	case 3: /* key ID + 3DES MAC -- unsupported! */