]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-llc.c
tcpdump.1 is generated from tcpdump.1.in.
[tcpdump] / print-llc.c
index 2d49d6180ee4c1e15e900c9d03fc46fe072b8c4a..0c8259fbb6b8a3b38ba1405cf28c515e33de8119 100644 (file)
  */
 
 #ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.34 2001-01-15 03:24:00 guy Exp $";
+static const char rcsid[] _U_ =
+    "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.75 2007-04-13 09:43:11 hannes Exp $";
 #endif
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <sys/param.h>
-#include <sys/time.h>
+#include <tcpdump-stdinc.h>
 
-#include <netinet/in.h>
-
-#include <ctype.h>
-#include <netdb.h>
 #include <stdio.h>
 #include <string.h>
 
@@ -46,8 +41,29 @@ static const char rcsid[] =
 #include "extract.h"                   /* must come after interface.h */
 
 #include "llc.h"
+#include "ethertype.h"
+#include "oui.h"
+
+static struct tok llc_values[] = {
+        { LLCSAP_NULL,     "Null" },
+        { LLCSAP_GLOBAL,   "Global" },
+        { LLCSAP_8021B_I,  "802.1B I" },
+        { LLCSAP_8021B_G,  "802.1B G" },
+        { LLCSAP_IP,       "IP" },
+        { LLCSAP_SNA,      "SNA" },
+        { LLCSAP_PROWAYNM, "ProWay NM" },
+        { LLCSAP_8021D,    "STP" },
+        { LLCSAP_RS511,    "RS511" },
+        { LLCSAP_ISO8208,  "ISO8208" },
+        { LLCSAP_PROWAY,   "ProWay" },
+        { LLCSAP_SNAP,     "SNAP" },
+        { LLCSAP_IPX,      "IPX" },
+        { LLCSAP_NETBEUI,  "NetBeui" },
+        { LLCSAP_ISONS,    "OSI" },
+        { 0,               NULL },
+};
 
-static struct tok cmd2str[] = {
+static struct tok llc_cmd_values[] = {
        { LLC_UI,       "ui" },
        { LLC_TEST,     "test" },
        { LLC_XID,      "xid" },
@@ -59,6 +75,74 @@ static struct tok cmd2str[] = {
        { 0,            NULL }
 };
 
+static const struct tok llc_flag_values[] = { 
+        { 0, "Command" },
+        { LLC_GSAP, "Response" },
+        { LLC_U_POLL, "Poll" },
+        { LLC_GSAP|LLC_U_POLL, "Final" },
+        { LLC_IS_POLL, "Poll" },
+        { LLC_GSAP|LLC_IS_POLL, "Final" },
+       { 0, NULL }
+};
+
+
+static const struct tok llc_ig_flag_values[] = { 
+        { 0, "Individual" },
+        { LLC_IG, "Group" },
+       { 0, NULL }
+};
+
+
+static const struct tok llc_supervisory_values[] = { 
+        { 0, "Receiver Ready" },
+        { 1, "Receiver not Ready" },
+        { 2, "Reject" },
+       { 0,             NULL }
+};
+
+
+static const struct tok cisco_values[] = { 
+       { PID_CISCO_CDP, "CDP" },
+       { PID_CISCO_VTP, "VTP" },
+       { PID_CISCO_DTP, "DTP" },
+       { PID_CISCO_UDLD, "UDLD" },
+       { PID_CISCO_PVST, "PVST" },
+       { 0,             NULL }
+};
+
+static const struct tok bridged_values[] = { 
+       { PID_RFC2684_ETH_FCS,     "Ethernet + FCS" },
+       { PID_RFC2684_ETH_NOFCS,   "Ethernet w/o FCS" },
+       { PID_RFC2684_802_4_FCS,   "802.4 + FCS" },
+       { PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" },
+       { PID_RFC2684_802_5_FCS,   "Token Ring + FCS" },
+       { PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" },
+       { PID_RFC2684_FDDI_FCS,    "FDDI + FCS" },
+       { PID_RFC2684_FDDI_NOFCS,  "FDDI w/o FCS" },
+       { PID_RFC2684_802_6_FCS,   "802.6 + FCS" },
+       { PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" },
+       { PID_RFC2684_BPDU,        "BPDU" },
+       { 0,                       NULL },
+};
+
+static const struct tok null_values[] = { 
+       { 0,             NULL }
+};
+
+struct oui_tok {
+       u_int32_t       oui;
+       const struct tok *tok;
+};
+
+static const struct oui_tok oui_to_tok[] = {
+       { OUI_ENCAP_ETHER, ethertype_values },
+       { OUI_CISCO_90, ethertype_values },     /* uses some Ethertype values */
+       { OUI_APPLETALK, ethertype_values },    /* uses some Ethertype values */
+       { OUI_CISCO, cisco_values },
+       { OUI_RFC2684, bridged_values },        /* bridged, RFC 2427 FR or RFC 2864 ATM */
+       { 0, NULL }
+};
+
 /*
  * Returns non-zero IFF it succeeds in printing the header
  */
@@ -66,21 +150,53 @@ int
 llc_print(const u_char *p, u_int length, u_int caplen,
          const u_char *esrc, const u_char *edst, u_short *extracted_ethertype)
 {
-       struct llc llc;
-       register u_short et;
+       u_int8_t dsap_field, dsap, ssap_field, ssap;
        u_int16_t control;
+       int is_u;
        register int ret;
 
+       *extracted_ethertype = 0;
+
        if (caplen < 3) {
                (void)printf("[|llc]");
                default_print((u_char *)p, caplen);
                return(0);
        }
 
-       /* Watch out for possible alignment problems */
-       memcpy((char *)&llc, (char *)p, min(caplen, sizeof(llc)));
+       dsap_field = *p;
+       ssap_field = *(p + 1);
+
+       /*
+        * OK, what type of LLC frame is this?  The length
+        * of the control field depends on that - I frames
+        * have a two-byte control field, and U frames have
+        * a one-byte control field.
+        */
+       control = *(p + 2);
+       if ((control & LLC_U_FMT) == LLC_U_FMT) {
+               /*
+                * U frame.
+                */
+               is_u = 1;
+       } else {
+               /*
+                * The control field in I and S frames is
+                * 2 bytes...
+                */
+               if (caplen < 4) {
+                       (void)printf("[|llc]");
+                       default_print((u_char *)p, caplen);
+                       return(0);
+               }
+
+               /*
+                * ...and is little-endian.
+                */
+               control = EXTRACT_LE_16BITS(p + 2);
+               is_u = 0;
+       }
 
-       if (llc.ssap == LLCSAP_GLOBAL && llc.dsap == LLCSAP_GLOBAL) {
+       if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) {
                /*
                 * This is an Ethernet_802.3 IPX frame; it has an
                 * 802.3 header (i.e., an Ethernet header where the
@@ -89,26 +205,53 @@ llc_print(const u_char *p, u_int length, u_int caplen,
                 * the IPX packet starts right after the Ethernet header,
                 * with a signature of two bytes of 0xFF (which is
                 * LLCSAP_GLOBAL).
+                *
+                * (It might also have been an Ethernet_802.3 IPX at
+                * one time, but got bridged onto another network,
+                * such as an 802.11 network; this has appeared in at
+                * least one capture file.)
                 */
-               ipx_print(p, length);
-               return (1);
+
+            if (eflag)
+               printf("IPX 802.3: ");
+
+            ipx_print(p, length);
+            return (1);
        }
 
-       /* Cisco Discovery Protocol  - SNAP & ether type 0x2000 */
-       if(llc.ssap == LLCSAP_SNAP && llc.dsap == LLCSAP_SNAP &&
-               llc.llcui == LLC_UI && 
-               llc.ethertype[0] == 0x20 && llc.ethertype[1] == 0x00 ) {
-                   cdp_print( p, length, caplen, esrc, edst);
-                   return (1);
+       dsap = dsap_field & ~LLC_IG;
+       ssap = ssap_field & ~LLC_GSAP;
+
+       if (eflag) {
+                printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s",
+                       tok2str(llc_values, "Unknown", dsap),
+                       dsap,
+                       tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG),
+                       tok2str(llc_values, "Unknown", ssap),
+                       ssap,
+                       tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP));
+
+               if (is_u) {
+                       printf(", ctrl 0x%02x: ", control);
+               } else {
+                       printf(", ctrl 0x%04x: ", control);
+               }
+       }
+
+       if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
+           control == LLC_UI) {
+               stp_print(p+3, length-3);
+               return (1);
        }
 
-       if (llc.ssap == LLCSAP_8021D && llc.dsap == LLCSAP_8021D) {
-               stp_print(p, length);
+       if (ssap == LLCSAP_IP && dsap == LLCSAP_IP &&
+           control == LLC_UI) {
+               ip_print(gndo, p+4, length-4);
                return (1);
        }
 
-       if (llc.ssap == LLCSAP_IPX && llc.dsap == LLCSAP_IPX &&
-           llc.llcui == LLC_UI) {
+       if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX &&
+           control == LLC_UI) {
                /*
                 * This is an Ethernet_802.2 IPX frame, with an 802.3
                 * header and an 802.2 LLC header with the source and
@@ -116,15 +259,16 @@ llc_print(const u_char *p, u_int length, u_int caplen,
                 *
                 * Skip DSAP, LSAP, and control field.
                 */
-               p += 3;
-               length -= 3;
-               caplen -= 3;
-               ipx_print(p, length);
+                if (eflag)
+                        printf("IPX 802.2: ");
+
+               ipx_print(p+3, length-3);
                return (1);
        }
 
-       if (llc.ssap == 0xf0 && llc.dsap == 0xf0
-           && (!(llc.llcu & LLC_S_FMT) || llc.llcu == LLC_U_FMT)) {
+#ifdef TCPDUMP_DO_SMB
+       if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
+           && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
                /*
                 * we don't actually have a full netbeui parser yet, but the
                 * smb parser can handle many smb-in-netbeui packets, which
@@ -137,107 +281,74 @@ llc_print(const u_char *p, u_int length, u_int caplen,
                 */
 
                /*
-                * Skip the DSAP and LSAP.
-                */
-               p += 2;
-               length -= 2;
-               caplen -= 2;
-
-               /*
-                * OK, what type of LLC frame is this?  The length
-                * of the control field depends on that - I frames
-                * have a two-byte control field, and U frames have
-                * a one-byte control field.
+                * Skip the LLC header.
                 */
-               if (llc.llcu == LLC_U_FMT) {
-                       control = llc.llcu;
-                       p += 1;
-                       length -= 1;
-                       caplen -= 1;
+               if (is_u) {
+                       p += 3;
+                       length -= 3;
+                       caplen -= 3;
                } else {
-                       /*
-                        * The control field in I and S frames is
-                        * little-endian.
-                        */
-                       control = EXTRACT_LE_16BITS(&llc.llcu);
-                       p += 2;
-                       length -= 2;
-                       caplen -= 2;
+                       p += 4;
+                       length -= 4;
+                       caplen -= 4;
                }
-               netbeui_print(control, p, p + min(caplen, length));
+               netbeui_print(control, p, length);
                return (1);
        }
-       if (llc.ssap == LLCSAP_ISONS && llc.dsap == LLCSAP_ISONS
-           && llc.llcui == LLC_UI) {
-               isoclns_print(p + 3, length - 3, caplen - 3, esrc, edst);
+#endif
+       if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
+           && control == LLC_UI) {
+               isoclns_print(p + 3, length - 3, caplen - 3);
                return (1);
        }
 
-       if (llc.ssap == LLCSAP_SNAP && llc.dsap == LLCSAP_SNAP
-           && llc.llcui == LLC_UI) {
-               if (caplen < sizeof(llc)) {
-                       (void)printf("[|llc-snap]");
-                       default_print((u_char *)p, caplen);
-                       return (0);
-               }
-               if (vflag)
-                       (void)printf("snap %s ", protoid_string(llc.llcpi));
-
-               caplen -= sizeof(llc);
-               length -= sizeof(llc);
-               p += sizeof(llc);
-
-               /* This is an encapsulated Ethernet packet */
-               et = EXTRACT_16BITS(&llc.ethertype[0]);
-               ret = ether_encap_print(et, p, length, caplen,
-                   extracted_ethertype);
+       if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
+           && control == LLC_UI) {
+               /*
+                * XXX - what *is* the right bridge pad value here?
+                * Does anybody ever bridge one form of LAN traffic
+                * over a networking type that uses 802.2 LLC?
+                */
+               ret = snap_print(p+3, length-3, caplen-3, extracted_ethertype,
+                   2);
                if (ret)
                        return (ret);
        }
 
-       if ((llc.ssap & ~LLC_GSAP) == llc.dsap) {
-               if (eflag)
-                       (void)printf("%s ", llcsap_string(llc.dsap));
-               else
-                       (void)printf("%s > %s %s ",
+       if (!eflag) {
+               if (ssap == dsap) {
+                       if (esrc == NULL || edst == NULL)
+                               (void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
+                       else
+                               (void)printf("%s > %s %s ",
+                                               etheraddr_string(esrc),
+                                               etheraddr_string(edst),
+                                               tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
+               } else {
+                       if (esrc == NULL || edst == NULL)
+                               (void)printf("%s > %s ",
+                                        tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
+                                       tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
+                       else
+                               (void)printf("%s %s > %s %s ",
                                        etheraddr_string(esrc),
+                                        tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
                                        etheraddr_string(edst),
-                                       llcsap_string(llc.dsap));
-       } else {
-               if (eflag)
-                       (void)printf("%s > %s ",
-                               llcsap_string(llc.ssap & ~LLC_GSAP),
-                               llcsap_string(llc.dsap));
-               else
-                       (void)printf("%s %s > %s %s ",
-                               etheraddr_string(esrc),
-                               llcsap_string(llc.ssap & ~LLC_GSAP),
-                               etheraddr_string(edst),
-                               llcsap_string(llc.dsap));
-       }
-
-       if ((llc.llcu & LLC_U_FMT) == LLC_U_FMT) {
-               u_int16_t cmd;
-               const char *m;
-               char f;
-
-               cmd = LLC_U_CMD(llc.llcu);
-               m = tok2str(cmd2str, "%02x", cmd);
-               switch ((llc.ssap & LLC_GSAP) | (llc.llcu & LLC_U_POLL)) {
-                       case 0:                 f = 'C'; break;
-                       case LLC_GSAP:          f = 'R'; break;
-                       case LLC_U_POLL:        f = 'P'; break;
-                       case LLC_GSAP|LLC_U_POLL: f = 'F'; break;
-                       default:                f = '?'; break;
+                                       tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
                }
+       }
 
-               printf("%s/%c", m, f);
+       if (is_u) {
+               printf("Unnumbered, %s, Flags [%s], length %u",
+                       tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)),
+                       tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)),
+                       length);
 
                p += 3;
                length -= 3;
                caplen -= 3;
 
-               if ((llc.llcu & ~LLC_U_POLL) == LLC_XID) {
+               if ((control & ~LLC_U_POLL) == LLC_XID) {
                        if (*p == LLC_XID_FI) {
                                printf(": %02x %02x", p[1], p[2]);
                                p += 3;
@@ -246,36 +357,193 @@ llc_print(const u_char *p, u_int length, u_int caplen,
                        }
                }
        } else {
-               char f;
-
-               /*
-                * The control field in I and S frames is little-endian.
-                */
-               control = EXTRACT_LE_16BITS(&llc.llcu);
-               switch ((llc.ssap & LLC_GSAP) | (control & LLC_IS_POLL)) {
-                       case 0:                 f = 'C'; break;
-                       case LLC_GSAP:          f = 'R'; break;
-                       case LLC_IS_POLL:       f = 'P'; break;
-                       case LLC_GSAP|LLC_IS_POLL: f = 'F'; break;
-                       default:                f = '?'; break;
-               }
-
                if ((control & LLC_S_FMT) == LLC_S_FMT) {
-                       static char *llc_s[] = { "rr", "rej", "rnr", "03" };
-                       (void)printf("%s (r=%d,%c)",
-                               llc_s[LLC_S_CMD(control)],
+                       (void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u",
+                               tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)),
                                LLC_IS_NR(control),
-                               f);
+                               tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
+                                length);
                } else {
-                       (void)printf("I (s=%d,r=%d,%c)",
+                       (void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u",
                                LLC_I_NS(control),
                                LLC_IS_NR(control),
-                               f);
+                               tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
+                                length);
                }
                p += 4;
                length -= 4;
                caplen -= 4;
        }
-       (void)printf(" len=%d", length);
        return(1);
 }
+
+int
+snap_print(const u_char *p, u_int length, u_int caplen,
+    u_short *extracted_ethertype, u_int bridge_pad)
+{
+       u_int32_t orgcode;
+       register u_short et;
+       register int ret;
+
+       TCHECK2(*p, 5);
+       orgcode = EXTRACT_24BITS(p);
+       et = EXTRACT_16BITS(p + 3);
+
+       if (eflag) {
+               const struct tok *tok = null_values;
+               const struct oui_tok *otp;
+
+               for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
+                       if (otp->oui == orgcode) {
+                               tok = otp->tok;
+                               break;
+                       }
+               }
+               (void)printf("oui %s (0x%06x), %s %s (0x%04x): ",
+                    tok2str(oui_values, "Unknown", orgcode),
+                    orgcode,
+                    (orgcode == 0x000000 ? "ethertype" : "pid"),
+                    tok2str(tok, "Unknown", et),
+                    et);
+       }
+       p += 5;
+       length -= 5;
+       caplen -= 5;
+
+       switch (orgcode) {
+       case OUI_ENCAP_ETHER:
+       case OUI_CISCO_90:
+               /*
+                * This is an encapsulated Ethernet packet,
+                * or a packet bridged by some piece of
+                * Cisco hardware; the protocol ID is
+                * an Ethernet protocol type.
+                */
+               ret = ether_encap_print(et, p, length, caplen,
+                   extracted_ethertype);
+               if (ret)
+                       return (ret);
+               break;
+
+       case OUI_APPLETALK:
+               if (et == ETHERTYPE_ATALK) {
+                       /*
+                        * No, I have no idea why Apple used one
+                        * of their own OUIs, rather than
+                        * 0x000000, and an Ethernet packet
+                        * type, for Appletalk data packets,
+                        * but used 0x000000 and an Ethernet
+                        * packet type for AARP packets.
+                        */
+                       ret = ether_encap_print(et, p, length, caplen,
+                           extracted_ethertype);
+                       if (ret)
+                               return (ret);
+               }
+               break;
+
+       case OUI_CISCO:
+                switch (et) {
+                case PID_CISCO_CDP:
+                        cdp_print(p, length, caplen);
+                        return (1);
+                case PID_CISCO_DTP:
+                        dtp_print(p, length); 
+                        return (1);
+                case PID_CISCO_UDLD:
+                        udld_print(p, length);
+                        return (1);
+                case PID_CISCO_VTP:
+                        vtp_print(p, length);
+                        return (1);
+                case PID_CISCO_PVST:
+                        stp_print(p, length);
+                        return (1);
+                default:
+                        break;
+                }
+
+       case OUI_RFC2684:
+               switch (et) {
+
+               case PID_RFC2684_ETH_FCS:
+               case PID_RFC2684_ETH_NOFCS:
+                       /*
+                        * XXX - remove the last two bytes for
+                        * PID_RFC2684_ETH_FCS?
+                        */
+                       /*
+                        * Skip the padding.
+                        */
+                       TCHECK2(*p, bridge_pad);
+                       caplen -= bridge_pad;
+                       length -= bridge_pad;
+                       p += bridge_pad;
+
+                       /*
+                        * What remains is an Ethernet packet.
+                        */
+                       ether_print(p, length, caplen);
+                       return (1);
+
+               case PID_RFC2684_802_5_FCS:
+               case PID_RFC2684_802_5_NOFCS:
+                       /*
+                        * XXX - remove the last two bytes for
+                        * PID_RFC2684_ETH_FCS?
+                        */
+                       /*
+                        * Skip the padding, but not the Access
+                        * Control field.
+                        */
+                       TCHECK2(*p, bridge_pad);
+                       caplen -= bridge_pad;
+                       length -= bridge_pad;
+                       p += bridge_pad;
+
+                       /*
+                        * What remains is an 802.5 Token Ring
+                        * packet.
+                        */
+                       token_print(p, length, caplen);
+                       return (1);
+
+               case PID_RFC2684_FDDI_FCS:
+               case PID_RFC2684_FDDI_NOFCS:
+                       /*
+                        * XXX - remove the last two bytes for
+                        * PID_RFC2684_ETH_FCS?
+                        */
+                       /*
+                        * Skip the padding.
+                        */
+                       TCHECK2(*p, bridge_pad + 1);
+                       caplen -= bridge_pad + 1;
+                       length -= bridge_pad + 1;
+                       p += bridge_pad + 1;
+
+                       /*
+                        * What remains is an FDDI packet.
+                        */
+                       fddi_print(p, length, caplen);
+                       return (1);
+
+               case PID_RFC2684_BPDU:
+                       stp_print(p, length);
+                       return (1);
+               }
+       }
+       return (0);
+
+trunc:
+       (void)printf("[|snap]");
+       return (1);
+}
+
+
+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 8
+ * End:
+ */