]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-arp.c
better print the IP addresses native than using getname();
[tcpdump] / print-arp.c
index 1ef2505f941a830b1defcde4fd0b1734f605e621..93a5a220da4a5203389d185397dc142e12487022 100644 (file)
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-arp.c,v 1.46 2000-09-23 08:03:31 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-arp.c,v 1.54 2002-07-11 09:17:23 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -30,11 +30,6 @@ static const char rcsid[] =
 
 #include <sys/param.h>
 #include <sys/time.h>
-#include <sys/socket.h>
-
-struct mbuf;
-struct rtentry;
-#include <net/if.h>
 
 #include <netinet/in.h>
 
@@ -57,11 +52,14 @@ struct rtentry;
  * arp_tha and arp_tpa in that order, according to the lengths
  * specified.  Field names used correspond to RFC 826.
  */
-struct arphdr {
+struct arp_pkthdr {
        u_short ar_hrd;         /* format of hardware address */
 #define ARPHRD_ETHER   1       /* ethernet hardware format */
 #define ARPHRD_IEEE802 6       /* token-ring hardware format */
+#define ARPHRD_ARCNET  7       /* arcnet hardware format */
 #define ARPHRD_FRELAY  15      /* frame relay hardware format */
+#define ARPHRD_STRIP   23      /* Ricochet Starmode Radio hardware format */
+#define ARPHRD_IEEE1394        24      /* IEEE 1394 (FireWire) hardware format */
        u_short ar_pro;         /* format of protocol address */
        u_char  ar_hln;         /* length of hardware address */
        u_char  ar_pln;         /* length of protocol address */
@@ -82,113 +80,215 @@ struct    arphdr {
        u_char  ar_tha[];       /* target hardware address */
        u_char  ar_tpa[];       /* target protocol address */
 #endif
+#define ar_sha(ap)     (((const u_char *)((ap)+1))+0)
+#define ar_spa(ap)     (((const u_char *)((ap)+1))+  (ap)->ar_hln)
+#define ar_tha(ap)     (((const u_char *)((ap)+1))+  (ap)->ar_hln+(ap)->ar_pln)
+#define ar_tpa(ap)     (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln)
 };
 
+#define ARP_HDRLEN     8
+
+#define HRD(ap) ((ap)->ar_hrd)
+#define HLN(ap) ((ap)->ar_hln)
+#define PLN(ap) ((ap)->ar_pln)
+#define OP(ap)  ((ap)->ar_op)
+#define PRO(ap) ((ap)->ar_pro)
+#define SHA(ap) (ar_sha(ap))
+#define SPA(ap) (ar_spa(ap))
+#define THA(ap) (ar_tha(ap))
+#define TPA(ap) (ar_tpa(ap))
+
 /*
- * Ethernet Address Resolution Protocol.
+ * ATM Address Resolution Protocol.
  *
- * See RFC 826 for protocol description.  Structure below is adapted
- * to resolving internet addresses.  Field names used correspond to 
- * RFC 826.
+ * See RFC 2225 for protocol description.  ARP packets are variable
+ * in size; the arphdr structure defines the fixed-length portion.
+ * Protocol type values are the same as those for 10 Mb/s Ethernet.
+ * It is followed by the variable-sized fields ar_sha, arp_spa,
+ * arp_tha and arp_tpa in that order, according to the lengths
+ * specified.  Field names used correspond to RFC 826.
  */
-struct ether_arp {
-       struct  arphdr ea_hdr;  /* fixed-size header */
-       u_char  arp_sha[6];     /* sender hardware address */
-       u_char  arp_spa[4];     /* sender protocol address */
-       u_char  arp_tha[6];     /* target hardware address */
-       u_char  arp_tpa[4];     /* target protocol address */
-};
-#define        arp_hrd ea_hdr.ar_hrd
-#define        arp_pro ea_hdr.ar_pro
-#define        arp_hln ea_hdr.ar_hln
-#define        arp_pln ea_hdr.ar_pln
-#define        arp_op  ea_hdr.ar_op
-
-#define SHA(ap) ((ap)->arp_sha)
-#define THA(ap) ((ap)->arp_tha)
-#define SPA(ap) ((ap)->arp_spa)
-#define TPA(ap) ((ap)->arp_tpa)
-
-/* Compatibility */
-#ifndef REVARP_REQUEST
-#define REVARP_REQUEST         3
-#endif
-#ifndef REVARP_REPLY
-#define REVARP_REPLY           4
+struct atmarp_pkthdr {
+       u_short ar_hrd;         /* format of hardware address */
+#define ARPHRD_ATM2225 19      /* ATM (RFC 2225) */
+       u_short ar_pro;         /* format of protocol address */
+       u_char  ar_shtl;        /* length of hardware address */
+       u_char  ar_sstl;        /* length of hardware address */
+       u_short ar_op;          /* same as regular ARP */
+       u_char  ar_spln;
+       u_char  ar_thtl;
+       u_char  ar_tstl;
+       u_char  ar_tpln;
+/*
+ * The remaining fields are variable in size,
+ * according to the sizes above.
+ */
+#ifdef COMMENT_ONLY
+       u_char  ar_sha[];       /* sender hardware address */
+       u_char  ar_spa[];       /* sender protocol address */
+       u_char  ar_tha[];       /* target hardware address */
+       u_char  ar_tpa[];       /* target protocol address */
 #endif
+#define ar_sha(ap)     (((const u_char *)((ap)+1))+0)
+#define ar_spa(ap)     (((const u_char *)((ap)+1))+  (ap)->ar_hln)
+#define ar_tha(ap)     (((const u_char *)((ap)+1))+  (ap)->ar_hln+(ap)->ar_pln)
+#define ar_tpa(ap)     (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln)
+};
 
 static u_char ezero[6];
 
-void
-arp_print(register const u_char *bp, u_int length, u_int caplen)
+static void
+atmarp_print(const u_char *bp, u_int length, u_int caplen)
 {
-       register const struct ether_arp *ap;
-       register const struct ether_header *eh;
-       register u_short pro, hrd, op;
+       const struct arp_pkthdr *ap;
+       u_short pro, hrd, op;
+
+       ap = (const struct arp_pkthdr *)bp;
+       TCHECK(*ap);
+       if ((const u_char *)(ar_tpa(ap) + PLN(ap)) > snapend) {
+               (void)printf("truncated-arp");
+               default_print((const u_char *)ap, length);
+               return;
+       }
+
+       hrd = EXTRACT_16BITS(&HRD(ap));
+       if (hrd == ARPHRD_ATM2225)
+               atmarp_print(bp, length, caplen);
+       pro = EXTRACT_16BITS(&PRO(ap));
+       op = EXTRACT_16BITS(&OP(ap));
+
+       if (pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) {
+               (void)printf("arp-#%d for proto #%d (%d) hardware #%d (%d)",
+                               op, pro, PLN(ap), hrd, HLN(ap));
+               return;
+       }
+       if (pro == ETHERTYPE_TRAIL)
+               (void)printf("trailer-");
+       switch (op) {
 
-       ap = (struct ether_arp *)bp;
-       if ((u_char *)(ap + 1) > snapend) {
-               printf("[|arp]");
+       case ARPOP_REQUEST:
+               (void)printf("arp who-has %s", ipaddr_string(TPA(ap)));
+               if (memcmp((const char *)ezero, (const char *)THA(ap), HLN(ap)) != 0)
+                       (void)printf(" (%s)",
+                           linkaddr_string(THA(ap), HLN(ap)));
+               (void)printf(" tell %s", ipaddr_string(SPA(ap)));
+               break;
+
+       case ARPOP_REPLY:
+               (void)printf("arp reply %s", ipaddr_string(SPA(ap)));
+               (void)printf(" is-at %s", linkaddr_string(SHA(ap), HLN(ap)));
+               break;
+
+       case ARPOP_REVREQUEST:
+               (void)printf("rarp who-is %s tell %s",
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       linkaddr_string(SHA(ap), HLN(ap)));
+               break;
+
+       case ARPOP_REVREPLY:
+               (void)printf("rarp reply %s at %s",
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       ipaddr_string(TPA(ap)));
+               break;
+
+       case ARPOP_INVREQUEST:
+               (void)printf("invarp who-is %s tell %s",
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       linkaddr_string(SHA(ap), HLN(ap)));
+               break;
+
+       case ARPOP_INVREPLY:
+               (void)printf("invarp reply %s at %s",
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       ipaddr_string(TPA(ap)));
+               break;
+
+       default:
+               (void)printf("arp-#%d", op);
+               default_print((const u_char *)ap, caplen);
                return;
        }
-       if (length < sizeof(struct ether_arp)) {
+       if (hrd != ARPHRD_ETHER)
+               printf(" hardware #%d", hrd);
+       return;
+trunc:
+       (void)printf("[|arp]");
+}
+
+void
+arp_print(const u_char *bp, u_int length, u_int caplen)
+{
+       const struct arp_pkthdr *ap;
+       u_short pro, hrd, op;
+
+       ap = (const struct arp_pkthdr *)bp;
+       TCHECK(*ap);
+       if ((const u_char *)(ar_tpa(ap) + PLN(ap)) > snapend) {
                (void)printf("truncated-arp");
-               default_print((u_char *)ap, length);
+               default_print((const u_char *)ap, length);
                return;
        }
 
-       pro = EXTRACT_16BITS(&ap->arp_pro);
-       hrd = EXTRACT_16BITS(&ap->arp_hrd);
-       op = EXTRACT_16BITS(&ap->arp_op);
+       hrd = EXTRACT_16BITS(&HRD(ap));
+       if (hrd == ARPHRD_ATM2225)
+               atmarp_print(bp, length, caplen);
+       pro = EXTRACT_16BITS(&PRO(ap));
+       op = EXTRACT_16BITS(&OP(ap));
 
-       if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL)
-           || ap->arp_hln != sizeof(SHA(ap))
-           || ap->arp_pln != sizeof(SPA(ap))) {
+       if (pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) {
                (void)printf("arp-#%d for proto #%d (%d) hardware #%d (%d)",
-                               op, pro, ap->arp_pln,
-                               hrd, ap->arp_hln);
+                               op, pro, PLN(ap), hrd, HLN(ap));
                return;
        }
        if (pro == ETHERTYPE_TRAIL)
                (void)printf("trailer-");
-       eh = (struct ether_header *)packetp;
        switch (op) {
 
        case ARPOP_REQUEST:
                (void)printf("arp who-has %s", ipaddr_string(TPA(ap)));
-               if (memcmp((char *)ezero, (char *)THA(ap), 6) != 0)
-                       (void)printf(" (%s)", etheraddr_string(THA(ap)));
+               if (memcmp((const char *)ezero, (const char *)THA(ap), HLN(ap)) != 0)
+                       (void)printf(" (%s)",
+                           linkaddr_string(THA(ap), HLN(ap)));
                (void)printf(" tell %s", ipaddr_string(SPA(ap)));
-               if (memcmp((char *)ESRC(eh), (char *)SHA(ap), 6) != 0)
-                       (void)printf(" (%s)", etheraddr_string(SHA(ap)));
                break;
 
        case ARPOP_REPLY:
                (void)printf("arp reply %s", ipaddr_string(SPA(ap)));
-               if (memcmp((char *)ESRC(eh), (char *)SHA(ap), 6) != 0)
-                       (void)printf(" (%s)", etheraddr_string(SHA(ap)));
-               (void)printf(" is-at %s", etheraddr_string(SHA(ap)));
-               if (memcmp((char *)EDST(eh), (char *)THA(ap), 6) != 0)
-                       (void)printf(" (%s)", etheraddr_string(THA(ap)));
+               (void)printf(" is-at %s", linkaddr_string(SHA(ap), HLN(ap)));
                break;
 
-       case REVARP_REQUEST:
+       case ARPOP_REVREQUEST:
                (void)printf("rarp who-is %s tell %s",
-                       etheraddr_string(THA(ap)),
-                       etheraddr_string(SHA(ap)));
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       linkaddr_string(SHA(ap), HLN(ap)));
                break;
 
-       case REVARP_REPLY:
+       case ARPOP_REVREPLY:
                (void)printf("rarp reply %s at %s",
-                       etheraddr_string(THA(ap)),
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       ipaddr_string(TPA(ap)));
+               break;
+
+       case ARPOP_INVREQUEST:
+               (void)printf("invarp who-is %s tell %s",
+                       linkaddr_string(THA(ap), HLN(ap)),
+                       linkaddr_string(SHA(ap), HLN(ap)));
+               break;
+
+       case ARPOP_INVREPLY:
+               (void)printf("invarp reply %s at %s",
+                       linkaddr_string(THA(ap), HLN(ap)),
                        ipaddr_string(TPA(ap)));
                break;
 
        default:
                (void)printf("arp-#%d", op);
-               default_print((u_char *)ap, caplen);
+               default_print((const u_char *)ap, caplen);
                return;
        }
        if (hrd != ARPHRD_ETHER)
                printf(" hardware #%d", hrd);
+       return;
+trunc:
+       (void)printf("[|arp]");
 }