From: Denis Ovsienko <denis@ovsienko.info>
Date: Sat, 17 Oct 2020 16:45:20 +0000 (+0100)
Subject: IPv6 Routing Header: Modernize packet parsing style.
X-Git-Tag: tcpdump-4.99-bp~88
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/0c0fca776b174b66460c3f8430b56e663abc4221

IPv6 Routing Header: Modernize packet parsing style.

Report an invalid packet as invalid with a reason, not truncated.
---

diff --git a/print-rt6.c b/print-rt6.c
index fba64670..096a9628 100644
--- a/print-rt6.c
+++ b/print-rt6.c
@@ -65,8 +65,10 @@ rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 			    GET_BE_U_4(dp0->ip6r0_reserved));
 		}
 
-		if (len % 2 == 1)
-			goto trunc;
+		if (len % 2 == 1) {
+			ND_PRINT(" (invalid length %u)", len);
+			goto invalid;
+		}
 		len >>= 1;
 		p = (const u_char *) dp0->ip6r0_addr;
 		for (i = 0; i < len; i++) {
@@ -88,8 +90,10 @@ rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 
 		ND_PRINT(", tag=%x", GET_BE_U_2(srh->srh_tag));
 
-		if (len % 2 == 1)
-			goto trunc;
+		if (len % 2 == 1) {
+			ND_PRINT(" (invalid length %u)", len);
+			goto invalid;
+		}
 		len >>= 1;
 		p  = (const u_char *) srh->srh_segments;
 		for (i = 0; i < len; i++) {
@@ -101,11 +105,11 @@ rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
 		return((GET_U_1(srh->srh_len) + 1) << 3);
 		break;
 	default:
-		goto trunc;
-		break;
+		ND_PRINT(" (unknown type)");
+		goto invalid;
 	}
 
- trunc:
-	nd_print_trunc(ndo);
+invalid:
+	nd_print_invalid(ndo);
 	return -1;
 }