Clean up the switch-tagged header code.

[tcpdump] / print-dsa.c

diff --git a/print-dsa.c b/print-dsa.c
index 3d142b28faf38c58d3fbb0bc5aad2127fa79b4fb..ad247959b558d3a870ca5c4fc6307a900b83216e 100644 (file)
--- a/print-dsa.c
+++ b/print-dsa.c
@@ -112,34 +112,35 @@ dsa_if_print_full(netdissect_options *ndo, const struct pcap_pkthdr *h,
                  const u_char *p, u_int taglen)
 {
        const u_char *edsa, *dsa;
-       int eflag, ret;
+       int save_eflag;
+       int ret;
 
-       if (h->caplen < 12 + taglen) {
+       if (h->caplen < 2*MAC_ADDR_LEN + taglen) {
                nd_print_trunc(ndo);
                return (h->caplen);
        }
 
-       if (h->len < 12 + taglen) {
+       if (h->len < 2*MAC_ADDR_LEN + taglen) {
                nd_print_trunc(ndo);
                return (h->len);
        }
 
        if (taglen == EDSA_LEN) {
-               edsa = p + 12;
+               edsa = p + 2*MAC_ADDR_LEN;
                dsa = edsa + 4;
        } else {
                edsa = NULL;
-               dsa = p + 12;
+               dsa = p + 2*MAC_ADDR_LEN;
        }
 
        if (ndo->ndo_eflag) {
                ND_PRINT("%s > %s, ",
-                        etheraddr_string(ndo, p + 6),
+                        etheraddr_string(ndo, p + MAC_ADDR_LEN),
                         etheraddr_string(ndo, p));
 
                if (edsa) {
                        ND_PRINT("Marvell EDSA ethertype 0x%04x (%s), ", EDSA_ETYPE(edsa),
-                                tok2str(ethertype_values, "unregistered", EDSA_ETYPE(edsa)));
+                                tok2str(ethertype_values, "Unknown", EDSA_ETYPE(edsa)));
                        ND_PRINT("rsvd %u %u, ", edsa[2], edsa[3]);
                } else {
                        ND_PRINT("Marvell DSA ");
@@ -209,11 +210,22 @@ dsa_if_print_full(netdissect_options *ndo, const struct pcap_pkthdr *h,
                ND_PRINT("VLAN %u%c, ", DSA_VID(dsa), DSA_TAGGED(dsa) ? 't' : 'u');
        }
 
-       eflag = ndo->ndo_eflag;
+       /* We printed the Ethernet destination and source addresses already */
+       save_eflag = ndo->ndo_eflag;
        ndo->ndo_eflag = 0;
+
+       /* Parse the rest of the Ethernet header, and the frame payload,
+        * telling ether_hdr_len_print() how big the non-standard Ethernet
+        * header is.
+        *
+        * +-----------+-----------+---------------------+--------------+
+        * | MAC DA (6)| MAC SA (6)|DSA/EDSA tag (taglen)|Type/Length(2)|
+        * +-----------+-----------+---------------------+--------------+
+        */
        ret = ether_hdr_len_print(ndo, p, h->len, h->caplen, NULL, NULL,
-                                 12 + taglen + 2);
-       ndo->ndo_eflag = eflag;
+                                 2*MAC_ADDR_LEN + taglen + 2);
+
+       ndo->ndo_eflag = save_eflag;
 
        return ret;
 }