]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-llc.c
The third argument to linkaddr_string is one of the LINKADDR_ enums.
[tcpdump] / print-llc.c
index 0132bdaa6b9ccecc7d0390a29c69abc6051bd7e4..750a8ccdae5499a4f2f5127922ae9b813dad90f4 100644 (file)
  *     with an awful lot of hacking by Jeffrey Mogul, DECWRL
  */
 
+/* \summary: IEEE 802.2 LLC printer */
+
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
 #endif
 
-#include <tcpdump-stdinc.h>
+#include "netdissect-stdinc.h"
 
-#include "interface.h"
+#include "netdissect.h"
 #include "addrtoname.h"
-#include "extract.h"                   /* must come after interface.h */
+#include "extract.h"
 
 #include "llc.h"
 #include "ethertype.h"
@@ -146,26 +148,27 @@ static const struct oui_tok oui_to_tok[] = {
  */
 int
 llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
-         const u_char *esrc, const u_char *edst)
+         const struct lladdr_info *src, const struct lladdr_info *dst)
 {
        uint8_t dsap_field, dsap, ssap_field, ssap;
        uint16_t control;
-       u_int hdrlen;
+       int hdrlen;
        int is_u;
 
+       ndo->ndo_protocol = "llc";
        if (caplen < 3) {
-               ND_PRINT((ndo, "[|llc]"));
-               ND_DEFAULTPRINT((u_char *)p, caplen);
+               nd_print_trunc(ndo);
+               ND_DEFAULTPRINT((const u_char *)p, caplen);
                return (caplen);
        }
        if (length < 3) {
-               ND_PRINT((ndo, "[|llc]"));
-               ND_DEFAULTPRINT((u_char *)p, caplen);
+               nd_print_trunc(ndo);
+               ND_DEFAULTPRINT((const u_char *)p, caplen);
                return (length);
        }
 
-       dsap_field = *p;
-       ssap_field = *(p + 1);
+       dsap_field = GET_U_1(p);
+       ssap_field = GET_U_1(p + 1);
 
        /*
         * OK, what type of LLC frame is this?  The length
@@ -173,7 +176,7 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
         * have a two-byte control field, and U frames have
         * a one-byte control field.
         */
-       control = *(p + 2);
+       control = GET_U_1(p + 2);
        if ((control & LLC_U_FMT) == LLC_U_FMT) {
                /*
                 * U frame.
@@ -186,20 +189,20 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                 * 2 bytes...
                 */
                if (caplen < 4) {
-                       ND_PRINT((ndo, "[|llc]"));
-                       ND_DEFAULTPRINT((u_char *)p, caplen);
+                       nd_print_trunc(ndo);
+                       ND_DEFAULTPRINT((const u_char *)p, caplen);
                        return (caplen);
                }
                if (length < 4) {
-                       ND_PRINT((ndo, "[|llc]"));
-                       ND_DEFAULTPRINT((u_char *)p, caplen);
+                       nd_print_trunc(ndo);
+                       ND_DEFAULTPRINT((const u_char *)p, caplen);
                        return (length);
                }
 
                /*
                 * ...and is little-endian.
                 */
-               control = EXTRACT_LE_16BITS(p + 2);
+               control = GET_LE_U_2(p + 2);
                is_u = 0;
                hdrlen = 4;     /* DSAP, SSAP, 2-byte control field */
        }
@@ -208,11 +211,11 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                /*
                 * This is an Ethernet_802.3 IPX frame; it has an
                 * 802.3 header (i.e., an Ethernet header where the
-                * type/length field is <= ETHERMTU, i.e. it's a length
-                * field, not a type field), but has no 802.2 header -
-                * the IPX packet starts right after the Ethernet header,
-                * with a signature of two bytes of 0xFF (which is
-                * LLCSAP_GLOBAL).
+                * type/length field is <= MAX_ETHERNET_LENGTH_VAL,
+                * i.e. it's a length field, not a type field), but
+                * has no 802.2 header - 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,
@@ -221,7 +224,7 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                 */
 
             if (ndo->ndo_eflag)
-               ND_PRINT((ndo, "IPX 802.3: "));
+               ND_PRINT("IPX 802.3: ");
 
             ipx_print(ndo, p, length);
             return (0);                /* no LLC header */
@@ -230,6 +233,22 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
        dsap = dsap_field & ~LLC_IG;
        ssap = ssap_field & ~LLC_GSAP;
 
+       if (ndo->ndo_eflag) {
+                ND_PRINT("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) {
+                       ND_PRINT(", ctrl 0x%02x: ", control);
+               } else {
+                       ND_PRINT(", ctrl 0x%04x: ", control);
+               }
+       }
+
        /*
         * Skip LLC header.
         */
@@ -237,13 +256,6 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
        length -= hdrlen;
        caplen -= hdrlen;
 
-       /*
-        * Check for SNAP UI packets; if we have one, there's no point
-        * in printing the LLC header information, as we already know it -
-        * the relevant protocol-selection information is the SNAP OUI
-        * and PID, so it's sufficient to print that for frames we
-        * don't know how to print and for the "-e" flag.
-        */
        if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
            && control == LLC_UI) {
                /*
@@ -251,7 +263,7 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                 * Does anybody ever bridge one form of LAN traffic
                 * over a networking type that uses 802.2 LLC?
                 */
-               if (!snap_print(ndo, p, length, caplen, esrc, edst, 2)) {
+               if (!snap_print(ndo, p, length, caplen, src, dst, 2)) {
                        /*
                         * Unknown packet type; tell our caller, by
                         * returning a negative value, so they
@@ -262,22 +274,6 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                        return (hdrlen + 5);    /* include LLC and SNAP header */
        }
 
-       if (ndo->ndo_eflag) {
-                ND_PRINT((ndo, "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) {
-                       ND_PRINT((ndo, ", ctrl 0x%02x: ", control));
-               } else {
-                       ND_PRINT((ndo, ", ctrl 0x%04x: ", control));
-               }
-       }
-
        if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
            control == LLC_UI) {
                stp_print(ndo, p, length);
@@ -304,13 +300,13 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                 * destination SAPs being the IPX SAP.
                 */
                 if (ndo->ndo_eflag)
-                        ND_PRINT((ndo, "IPX 802.2: "));
+                        ND_PRINT("IPX 802.2: ");
 
                ipx_print(ndo, p, length);
                return (hdrlen);
        }
 
-#ifdef TCPDUMP_DO_SMB
+#ifdef ENABLE_SMB
        if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
            && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
                /*
@@ -329,110 +325,128 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
 #endif
        if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
            && control == LLC_UI) {
-               isoclns_print(ndo, p, length, caplen);
+               isoclns_print(ndo, p, length);
                return (hdrlen);
        }
 
        if (!ndo->ndo_eflag) {
                if (ssap == dsap) {
-                       if (esrc == NULL || edst == NULL)
-                               ND_PRINT((ndo, "%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)));
+                       if (src == NULL || dst == NULL)
+                               ND_PRINT("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
                        else
-                               ND_PRINT((ndo, "%s > %s %s ",
-                                               etheraddr_string(ndo, esrc),
-                                               etheraddr_string(ndo, edst),
-                                               tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)));
+                               ND_PRINT("%s > %s %s ",
+                                               (src->addr_string)(ndo, src->addr),
+                                               (dst->addr_string)(ndo, dst->addr),
+                                               tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
                } else {
-                       if (esrc == NULL || edst == NULL)
-                               ND_PRINT((ndo, "%s > %s ",
+                       if (src == NULL || dst == NULL)
+                               ND_PRINT("%s > %s ",
                                         tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
-                                       tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)));
+                                       tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
                        else
-                               ND_PRINT((ndo, "%s %s > %s %s ",
-                                       etheraddr_string(ndo, esrc),
+                               ND_PRINT("%s %s > %s %s ",
+                                       (src->addr_string)(ndo, src->addr),
                                         tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
-                                       etheraddr_string(ndo, edst),
-                                       tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)));
+                                       (dst->addr_string)(ndo, dst->addr),
+                                       tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
                }
        }
 
        if (is_u) {
-               ND_PRINT((ndo, "Unnumbered, %s, Flags [%s], length %u",
+               ND_PRINT("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 + hdrlen));
+                       length + hdrlen);
 
                if ((control & ~LLC_U_POLL) == LLC_XID) {
-                       if (*p == LLC_XID_FI) {
-                               ND_PRINT((ndo, ": %02x %02x", p[1], p[2]));
+                       if (length == 0) {
+                               /*
+                                * XID with no payload.
+                                * This could, for example, be an SNA
+                                * "short form" XID.
+                                 */
+                               return (hdrlen);
+                       }
+                       if (caplen < 1) {
+                               nd_print_trunc(ndo);
+                               if (caplen > 0)
+                                       ND_DEFAULTPRINT((const u_char *)p, caplen);
+                               return (hdrlen);
+                       }
+                       if (GET_U_1(p) == LLC_XID_FI) {
+                               if (caplen < 3 || length < 3) {
+                                       nd_print_trunc(ndo);
+                                       if (caplen > 0)
+                                               ND_DEFAULTPRINT((const u_char *)p, caplen);
+                               } else
+                                       ND_PRINT(": %02x %02x",
+                                                 GET_U_1(p + 1),
+                                                 GET_U_1(p + 2));
                                return (hdrlen);
                        }
                }
        } else {
                if ((control & LLC_S_FMT) == LLC_S_FMT) {
-                       ND_PRINT((ndo, "Supervisory, %s, rcv seq %u, Flags [%s], length %u",
+                       ND_PRINT("Supervisory, %s, rcv seq %u, Flags [%s], length %u",
                                tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)),
                                LLC_IS_NR(control),
                                tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
-                                length + hdrlen));
+                                length + hdrlen);
                        return (hdrlen);        /* no payload to print */
                } else {
-                       ND_PRINT((ndo, "Information, send seq %u, rcv seq %u, Flags [%s], length %u",
+                       ND_PRINT("Information, send seq %u, rcv seq %u, Flags [%s], length %u",
                                LLC_I_NS(control),
                                LLC_IS_NR(control),
                                tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
-                                length + hdrlen));
+                                length + hdrlen);
                }
        }
        return (-hdrlen);
 }
 
-static void
-snap_hdr_print(netdissect_options *ndo, const uint8_t *esrc, const uint8_t *edst,
-       uint32_t orgcode, u_short et, u_int length)
+static const struct tok *
+oui_to_struct_tok(uint32_t orgcode)
 {
        const struct tok *tok = null_values;
        const struct oui_tok *otp;
 
-       if (esrc != NULL && edst != NULL) {
-               ND_PRINT((ndo, "%s > %s ",
-                               etheraddr_string(ndo, esrc),
-                               etheraddr_string(ndo, edst)));
-       }
        for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
                if (otp->oui == orgcode) {
                        tok = otp->tok;
                        break;
                }
        }
-       ND_PRINT((ndo, "SNAP oui %s (0x%06x), %s %s (0x%04x), length %u: ",
-            tok2str(oui_values, "Unknown", orgcode),
-            orgcode,
-            (orgcode == 0x000000 ? "ethertype" : "pid"),
-            tok2str(tok, "Unknown", et),
-            et, length));
+       return (tok);
 }
 
 int
 snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
-       const u_char *esrc, const u_char *edst, u_int bridge_pad)
+       const struct lladdr_info *src, const struct lladdr_info *dst,
+       u_int bridge_pad)
 {
        uint32_t orgcode;
-       register u_short et;
-       register int ret;
+       u_short et;
+       int ret;
 
-       ND_TCHECK2(*p, 5);
+       ndo->ndo_protocol = "snap";
+       ND_TCHECK_5(p);
        if (caplen < 5 || length < 5)
                goto trunc;
-       orgcode = EXTRACT_24BITS(p);
-       et = EXTRACT_16BITS(p + 3);
+       orgcode = GET_BE_U_3(p);
+       et = GET_BE_U_2(p + 3);
 
        if (ndo->ndo_eflag) {
                /*
                 * Somebody's already printed the MAC addresses, if there
-                * are any, so just print the SNAP header.
+                * are any, so just print the SNAP header, not the MAC
+                * addresses.
                 */
-               snap_hdr_print(ndo, NULL, NULL, orgcode, et, length - 5);
+               ND_PRINT("oui %s (0x%06x), %s %s (0x%04x), length %u: ",
+                    tok2str(oui_values, "Unknown", orgcode),
+                    orgcode,
+                    (orgcode == 0x000000 ? "ethertype" : "pid"),
+                    tok2str(oui_to_struct_tok(orgcode), "Unknown", et),
+                    et, length - 5);
        }
        p += 5;
        length -= 5;
@@ -447,7 +461,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                 * Cisco hardware; the protocol ID is
                 * an Ethernet protocol type.
                 */
-               ret = ethertype_print(ndo, et, p, length, caplen);
+               ret = ethertype_print(ndo, et, p, length, caplen, src, dst);
                if (ret)
                        return (ret);
                break;
@@ -462,7 +476,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                         * but used 0x000000 and an Ethernet
                         * packet type for AARP packets.
                         */
-                       ret = ethertype_print(ndo, et, p, length, caplen);
+                       ret = ethertype_print(ndo, et, p, length, caplen, src, dst);
                        if (ret)
                                return (ret);
                }
@@ -503,7 +517,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                        /*
                         * Skip the padding.
                         */
-                       ND_TCHECK2(*p, bridge_pad);
+                       ND_TCHECK_LEN(p, bridge_pad);
                        caplen -= bridge_pad;
                        length -= bridge_pad;
                        p += bridge_pad;
@@ -524,7 +538,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                         * Skip the padding, but not the Access
                         * Control field.
                         */
-                       ND_TCHECK2(*p, bridge_pad);
+                       ND_TCHECK_LEN(p, bridge_pad);
                        caplen -= bridge_pad;
                        length -= bridge_pad;
                        p += bridge_pad;
@@ -545,7 +559,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                        /*
                         * Skip the padding.
                         */
-                       ND_TCHECK2(*p, bridge_pad + 1);
+                       ND_TCHECK_LEN(p, bridge_pad + 1);
                        caplen -= bridge_pad + 1;
                        length -= bridge_pad + 1;
                        p += bridge_pad + 1;
@@ -561,19 +575,36 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen,
                        return (1);
                }
        }
-       if (!ndo->ndo_eflag)
-               snap_hdr_print(ndo, esrc, edst, orgcode, et, length);
+       if (!ndo->ndo_eflag) {
+               /*
+                * Nobody printed the link-layer addresses, so print them, if
+                * we have any.
+                */
+               if (src != NULL && dst != NULL) {
+                       ND_PRINT("%s > %s ",
+                               (src->addr_string)(ndo, src->addr),
+                               (dst->addr_string)(ndo, dst->addr));
+               }
+               /*
+                * Print the SNAP header, but if the OUI is 000000, don't
+                * bother printing it, and report the PID as being an
+                * ethertype.
+                */
+               if (orgcode == 0x000000) {
+                       ND_PRINT("SNAP, ethertype %s (0x%04x), length %u: ",
+                            tok2str(ethertype_values, "Unknown", et),
+                            et, length);
+               } else {
+                       ND_PRINT("SNAP, oui %s (0x%06x), pid %s (0x%04x), length %u: ",
+                            tok2str(oui_values, "Unknown", orgcode),
+                            orgcode,
+                            tok2str(oui_to_struct_tok(orgcode), "Unknown", et),
+                            et, length);
+               }
+       }
        return (0);
 
 trunc:
-       ND_PRINT((ndo, "[|snap]"));
+       nd_print_trunc(ndo);
        return (1);
 }
-
-
-/*
- * Local Variables:
- * c-style: whitesmith
- * c-basic-offset: 8
- * End:
- */