OSPF: Modernize some code.

Make a few one-byte fetches use GET_U_1().

In ospf_print_tos_metrics() lose an excess ND_TCHECK_SIZE() and make the
function void.

Make ospf_decode_lls() void -- the only case when it returned a non-zero
value was if the LLS block is invalid, and it already signals that with a
message. It is a separate matter if the invalid packet is also truncated,
and since there is no proper check for that, just return without printing
a misleading message.

Switch ospf_print() to nd_trunc_longjmp().

diff --git a/print-ospf.c b/print-ospf.c
index f5f37a3b1c61f0c9e7e7a6ba4cbb9bbba9a0133d..a385d7a1bfde05009150a4f25a4058e264a7a118 100644 (file)
--- a/print-ospf.c
+++ b/print-ospf.c
@@ -582,7 +582,7 @@ static const struct tok ospf_topology_values[] = {
 /*
  * Print all the per-topology metrics.
  */
-static int
+static void
 ospf_print_tos_metrics(netdissect_options *ndo,
                        const union un_tos *tos)
 {
@@ -597,7 +597,6 @@ ospf_print_tos_metrics(netdissect_options *ndo,
      * All but the first metric contain a valid topology id.
      */
     while (toscount != 0) {
-        ND_TCHECK_SIZE(tos);
         tos_type = GET_U_1(tos->metrics.tos_type);
         ND_PRINT("\n\t\ttopology %s (%u), metric %u",
                tok2str(ospf_topology_values, "Unknown",
@@ -608,9 +607,6 @@ ospf_print_tos_metrics(netdissect_options *ndo,
         tos++;
         toscount--;
     }
-    return 0;
-trunc:
-    return 1;
 }
 
 /*
@@ -688,8 +684,7 @@ ospf_print_lsa(netdissect_options *ndo,
                                return (ls_end);
                        }
 
-                       if (ospf_print_tos_metrics(ndo, &rlp->un_tos))
-                               goto trunc;
+                       ospf_print_tos_metrics(ndo, &rlp->un_tos);
 
                        rlp = (const struct rlalink *)((const u_char *)(rlp + 1) +
                            (GET_U_1(rlp->un_tos.link.link_tos_count) * sizeof(union un_tos)));
@@ -889,7 +884,7 @@ trunc:
        return (NULL);
 }
 
-static int
+static void
 ospf_decode_lls(netdissect_options *ndo,
                 const struct ospfhdr *op, u_int length)
 {
@@ -903,16 +898,16 @@ ospf_decode_lls(netdissect_options *ndo,
 
     case OSPF_TYPE_HELLO:
         if (!(GET_U_1(op->ospf_hello.hello_options) & OSPF_OPTION_L))
-            return (0);
+            return;
         break;
 
     case OSPF_TYPE_DD:
         if (!(GET_U_1(op->ospf_db.db_options) & OSPF_OPTION_L))
-            return (0);
+            return;
         break;
 
     default:
-        return (0);
+        return;
     }
 
     /* dig deeper if LLS data is available; see RFC4813 */
@@ -921,12 +916,12 @@ ospf_decode_lls(netdissect_options *ndo,
     dataend = (const u_char *)op + length;
 
     if (GET_BE_U_2(op->ospf_authtype) == OSPF_AUTH_MD5) {
-        dptr = dptr + op->ospf_authdata[3];
-        length2 += op->ospf_authdata[3];
+        dptr = dptr + GET_U_1(op->ospf_authdata + 3);
+        length2 += GET_U_1(op->ospf_authdata + 3);
     }
     if (length2 >= length) {
         ND_PRINT("\n\t[LLS truncated]");
-        return (1);
+        return;
     }
     ND_PRINT("\n\t  LLS: checksum: 0x%04x", (u_int) GET_BE_U_2(dptr));
 
@@ -968,8 +963,6 @@ ospf_decode_lls(netdissect_options *ndo,
 
         dptr += lls_len;
     }
-
-    return (0);
 }
 
 static int
@@ -1154,8 +1147,8 @@ ospf_print(netdissect_options *ndo,
 
                case OSPF_AUTH_MD5:
                        ND_PRINT("\n\tKey-ID: %u, Auth-Length: %u, Crypto Sequence Number: 0x%08x",
-                                 *((op->ospf_authdata) + 2),
-                                 *((op->ospf_authdata) + 3),
+                                 GET_U_1(op->ospf_authdata + 2),
+                                 GET_U_1(op->ospf_authdata + 3),
                                  GET_BE_U_4((op->ospf_authdata) + 4));
                        break;
 
@@ -1170,10 +1163,8 @@ ospf_print(netdissect_options *ndo,
                /* ospf version 2 */
                if (ospf_decode_v2(ndo, op, dataend))
                        goto trunc;
-               if (length > GET_BE_U_2(op->ospf_len)) {
-                       if (ospf_decode_lls(ndo, op, length))
-                               goto trunc;
-               }
+               if (length > GET_BE_U_2(op->ospf_len))
+                       ospf_decode_lls(ndo, op, length);
                break;
 
        default:
@@ -1183,5 +1174,5 @@ ospf_print(netdissect_options *ndo,
 
        return;
 trunc:
-       nd_print_trunc(ndo);
+       nd_trunc_longjmp(ndo);
 }