WB: Reorder printing of wb-id messages.

As struct pkt_id informally notes it, the site name string follows
"seqptr's", which is a sequence of zero or more (as encoded in the "nid"
field) struct id_off items. Try to print the string after trying to
print the sequence, so the output makes as much sense as possible for
truncated packets. Also remove one ND_TTEST_LEN() before a nd_print() so
the latter prints as much data as is available and deals with the
snapshot end.

While at it, rename and retype a pointer for clarity and lose two excess
type casts, also add a length sanity check.

diff --git a/print-wb.c b/print-wb.c
index a1a5306b7caf4a7940bc0ee8caf09eaf8139ac76..76e3fd5239df6ca0d4690a9d414c42158cf8bc95 100644 (file)
--- a/print-wb.c
+++ b/print-wb.c
@@ -180,7 +180,7 @@ wb_id(netdissect_options *ndo,
       const struct pkt_id *id, u_int len)
 {
        u_int i;
-       const char *cp;
+       const u_char *sitename;
        const struct id_off *io;
        char c;
        u_int nid;
@@ -199,14 +199,11 @@ wb_id(netdissect_options *ndo,
               GET_BE_U_4(id->pi_mpage.p_uid));
 
        nid = GET_BE_U_2(id->pi_ps.nid);
+       if (len < sizeof(*io) * nid)
+               return (-1);
        len -= sizeof(*io) * nid;
        io = (const struct id_off *)(id + 1);
-       cp = (const char *)(io + nid);
-       if (ND_TTEST_LEN(cp, len)) {
-               ND_PRINT("\"");
-               nd_print(ndo, (const u_char *)cp, (const u_char *)cp + len);
-               ND_PRINT("\"");
-       }
+       sitename = (const u_char *)(io + nid);
 
        c = '<';
        for (i = 0; i < nid && ND_TTEST_SIZE(io); ++io, ++i) {
@@ -215,7 +212,9 @@ wb_id(netdissect_options *ndo,
                c = ',';
        }
        if (i >= nid) {
-               ND_PRINT(">");
+               ND_PRINT("> \"");
+               (void)nd_print(ndo, sitename, sitename + len);
+               ND_PRINT("\"");
                return (0);
        }
        return (-1);