IPv6: Print 'No Next Header' when relevant

fxlb · fxlb · commit f27d16e80be1 · 2025-02-12T07:02:06.000Z
This avoids to print 'next-header unknown (59)' when it's the first
header.

Add a test file.
diff --git a/ipproto.c b/ipproto.c
@@ -39,6 +39,7 @@ const struct tok ipproto_values[] = {
     { IPPROTO_AH, "AH" },
     { IPPROTO_MOBILE, "Mobile IP" },
     { IPPROTO_ICMPV6, "ICMPv6" },
+    { IPPROTO_NONE, "No Next Header" },
     { IPPROTO_DSTOPTS, "DSTOPT" },
     { IPPROTO_MOBILITY_OLD, "Mobile IP (old)" },
     { IPPROTO_EIGRP, "EIGRP" },
diff --git a/tests/TESTLIST b/tests/TESTLIST
@@ -405,6 +405,7 @@ ipv6_jumbogram_invalid_length ipv6_jumbogram_invalid_length.pcap ipv6_jumbogram_
 ipv6_39_byte_header ipv6_39_byte_header.pcap ipv6_39_byte_header.out -v
 ipv6_missing_jumbo_payload_option ipv6_missing_jumbo_payload_option.pcap ipv6_missing_jumbo_payload_option.out
 ipv6_frag6_negative_len ipv6_frag6_negative_len.pcap ipv6_frag6_negative_len.out -v
+ipv6_no_next_header ipv6_no_next_header.pcap ipv6_no_next_header.out -v
 
 # Loopback/CTP test case
 loopback	loopback.pcap		loopback.out
diff --git a/tests/ipv6_no_next_header.out b/tests/ipv6_no_next_header.out
@@ -0,0 +1 @@
+    1  2025-02-11 13:31:22.134532 IP6 (hlim 64, next-header No Next Header (59), payload length 20) 2005::1 > 2008::1: no next header
diff --git a/tests/ipv6_no_next_header.pcap b/tests/ipv6_no_next_header.pcap

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+ 1 2025-02-11 13:31:22.134532 IP6 (hlim 64, next-header No Next Header (59), payload length 20) 2005::1 > 2008::1: no next header`