From: Denis Ovsienko <infrastation@yandex.ru>
Date: Thu, 31 Oct 2013 14:58:42 +0000 (+0400)
Subject: NFLOG: more minor improvements
X-Git-Tag: tcpdump-4.5.0~5
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/fc133e2edba0fce13d34813308e7523596f869e1

NFLOG: more minor improvements

Reduce pointer conversion and do version check before header decoding.
---

diff --git a/print-nflog.c b/print-nflog.c
index c2ea7b7b..adeecd39 100644
--- a/print-nflog.c
+++ b/print-nflog.c
@@ -50,11 +50,8 @@ static const struct tok nflog_values[] = {
 };
 
 static inline void
-nflog_hdr_print(struct netdissect_options *ndo, const u_char *bp, u_int length)
+nflog_hdr_print(struct netdissect_options *ndo, const nflog_hdr_t *hdr, u_int length)
 {
-	const nflog_hdr_t *hdr;
-	hdr = (const nflog_hdr_t *)bp;
-
 	ND_PRINT((ndo, "version %d, resource ID %d", hdr->nflog_version, ntohs(hdr->nflog_rid)));
 
 	if (!ndo->ndo_qflag) {
@@ -76,7 +73,7 @@ u_int
 nflog_if_print(struct netdissect_options *ndo,
 			   const struct pcap_pkthdr *h, const u_char *p)
 {
-	const nflog_hdr_t *hdr;
+	const nflog_hdr_t *hdr = (const nflog_hdr_t *)p;
 	const nflog_tlv_t *tlv;
 	u_int16_t size;
 	u_int16_t h_size = sizeof(nflog_hdr_t);
@@ -88,19 +85,18 @@ nflog_if_print(struct netdissect_options *ndo,
 		return h_size;
 	}
 
+	if (!(hdr->nflog_version) == 0) {
+		ND_PRINT((ndo, ", NFLOG version mismatch: %u", hdr->nflog_version));
+		return h_size;
+	}
+
 	if (ndo->ndo_eflag)
-		nflog_hdr_print(ndo, p, length);
+		nflog_hdr_print(ndo, hdr, length);
 
 	length -= sizeof(nflog_hdr_t);
 	caplen -= sizeof(nflog_hdr_t);
-	hdr = (const nflog_hdr_t *)p;
 	p += sizeof(nflog_hdr_t);
 
-	if (!(hdr->nflog_version) == 0) {
-		ND_PRINT((ndo, ", NFLOG version mismatch: %u", hdr->nflog_version));
-		return h_size;
-	}
-
 	do {
 		tlv = (const nflog_tlv_t *) p;
 		size = tlv->tlv_length;
@@ -140,7 +136,7 @@ nflog_if_print(struct netdissect_options *ndo,
 
 	default:
 		if (!ndo->ndo_eflag)
-			nflog_hdr_print(ndo, (u_char *)hdr,
+			nflog_hdr_print(ndo, hdr,
 				length + sizeof(nflog_hdr_t));
 
 		if (!ndo->ndo_suppress_default_print)