* Routines for Token-Ring packet disassembly
* Gilbert Ramirez <gram@verdict.uthscsa.edu>
*
- * $Id: packet-tr.c,v 1.7 1998/11/12 00:06:38 gram Exp $
+ * $Id: packet-tr.c,v 1.31 1999/11/16 11:43:00 guy Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@unicom.net>
# include "config.h"
#endif
-#include <gtk/gtk.h>
-
-#include <stdio.h>
-
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
-#ifdef HAVE_NETINET_IN_H
-# include <netinet/in.h>
-#endif
-
-
-#include "ethereal.h"
+#include <stdio.h>
+#include <glib.h>
#include "packet.h"
-#include "etypes.h"
+
+static int proto_tr = -1;
+static int hf_tr_dst = -1;
+static int hf_tr_src = -1;
+static int hf_tr_sr = -1;
+static int hf_tr_ac = -1;
+static int hf_tr_priority = -1;
+static int hf_tr_frame = -1;
+static int hf_tr_monitor_cnt = -1;
+static int hf_tr_priority_reservation = -1;
+static int hf_tr_fc = -1;
+static int hf_tr_fc_type = -1;
+static int hf_tr_fc_pcf = -1;
+static int hf_tr_rif_bytes = -1;
+static int hf_tr_broadcast = -1;
+static int hf_tr_max_frame_size = -1;
+static int hf_tr_direction = -1;
+static int hf_tr_rif = -1;
+static int hf_tr_rif_ring = -1;
+static int hf_tr_rif_bridge = -1;
+
+static gint ett_token_ring = -1;
+static gint ett_token_ring_ac = -1;
+static gint ett_token_ring_fc = -1;
+
+#define TR_MIN_HEADER_LEN 14
+#define TR_MAX_HEADER_LEN 32
+
+static const true_false_string ac_truth = { "Frame", "Token" };
+
+static const value_string pcf_vals[] = {
+ { 0, "Normal buffer" },
+ { 1, "Express buffer" },
+ { 2, "Purge" },
+ { 3, "Claim Token" },
+ { 4, "Beacon" },
+ { 5, "Active Monitor Present" },
+ { 6, "Standby Monitor Present" },
+ { 0, NULL },
+};
+
+static const value_string frame_vals[] = {
+ { 0, "MAC" },
+ { 1, "LLC" },
+ { 2, "Reserved" },
+ { 0, NULL },
+};
+
+static const value_string broadcast_vals[] = {
+ { 0 << 5, "Non-broadcast" },
+ { 1 << 5, "Non-broadcast" },
+ { 2 << 5, "Non-broadcast" },
+ { 3 << 5, "Non-broadcast" },
+ { 4 << 5, "All-routes broadcast" },
+ { 5 << 5, "All-routes broadcast" },
+ { 6 << 5, "Single-route broadcast" },
+ { 7 << 5, "Single-route broadcast" },
+ { 0, NULL }
+};
+
+static const value_string max_frame_size_vals[] = {
+ { 0, "516" },
+ { 1, "1500" },
+ { 2, "2052" },
+ { 3, "4472" },
+ { 4, "8144" },
+ { 5, "11407" },
+ { 6, "17800" },
+ { 0, NULL }
+};
+
+static const value_string direction_vals[] = {
+ { 0, "From originating station (-->)" },
+ { 128, "To originating station (<--)" },
+ { 0, NULL }
+};
+
+/*
+ * DODGY LINUX HACK DODGY LINUX HACK
+ * Linux 2.0.x always passes frames to the Token Ring driver for transmission with
+ * 18 bytes padding for source routing information. Some drivers copy the first
+ * (18 - srlen) bytes up the frame (18 - srlen) bytes thus removing the padding.
+ * Other drivers just make a copy of the entire frame and then hack about with it
+ * so the frame the sniffer gets is fine (just has extra sr routing).
+ * In the first instance (driver hacking frame in situ) the sniffer gets a garbled
+ * frame.
+ * This function trys to detect this and returns the offset of where
+ * the frame really starts.
+ * This only detects frames that we have sent ourselves so if we are packet sniffing
+ * on the machine we are watching this is useful.
+ * Compare offset 0 with offset x+1 for a length of x bytes for all value of x = 1 to 18
+ * if match then Linux driver has done in situ source route compression of the crappy
+ * Linux 2.0.x frame so the beginning of the real frame is x bytes in.
+ * (And this real frame x bytes in looks like a proper TR frame that goes on the wire
+ * with none of the Linux idiosyncrasies).
+ */
+int check_for_old_linux(const u_char * pd)
+{
+ int x;
+ for(x=1;x<=18;x++)
+ {
+ if (memcmp(&pd[0],&pd[x],x) == 0)
+ {
+ return x;
+ }
+ }
+ return 0;
+}
static void
-add_ring_bridge_pairs(int rcf_len, const u_char *pd, GtkWidget *tree);
+add_ring_bridge_pairs(int rcf_len, const u_char *pd, int offset, proto_tree *tree);
+
+void
+capture_tr(const u_char *pd, guint32 cap_len, packet_counts *ld) {
+
+ int offset = 0;
-static char*
-sr_broadcast(u_char val) {
+ int source_routed = 0;
+ int frame_type;
+ int x;
+ guint8 trn_rif_bytes;
+ guint8 actual_rif_bytes;
+
+ /* The trn_hdr struct, as separate variables */
+ guint8 trn_fc; /* field control field */
+ guint8 trn_shost[6]; /* source host */
- if (val < 4) {
- return "Non-broadcast";
+ if (cap_len < TR_MAX_HEADER_LEN) {
+ ld->other++;
+ return;
}
- else if (val < 6) {
- return "All-routes broadcast";
+
+ if ((x = check_for_old_linux(pd)))
+ {
+ /* Actually packet starts x bytes into what we have got but with all
+ source routing compressed
+ */
+ /* pd = &pd[x]; */ offset+=x;
}
- else {
- return "Single-route broadcast";
+
+ /* get the data */
+ memcpy(&trn_fc, &pd[offset + 1], sizeof(guint8));
+ memcpy(trn_shost, &pd[offset + 8], 6 * sizeof(guint8));
+
+ frame_type = (trn_fc & 192) >> 6;
+
+ /* if the high bit on the first byte of src hwaddr is 1, then
+ this packet is source-routed */
+ source_routed = trn_shost[0] & 128;
+
+ trn_rif_bytes = pd[offset + 14] & 31;
+
+ /* sometimes we have a RCF but no RIF... half source-routed? */
+ if (!source_routed && trn_rif_bytes > 0) {
+ /* I'll check for 2 bytes of RIF and mark the packet as source
+ * routed even though I'm not sure _what_ that kind of packet is */
+ if (trn_rif_bytes == 2) {
+ source_routed = 1;
+ }
+ /* the Linux 2.0 TR code strips source-route bits in
+ * order to test for SR. This can be removed from most
+ * packets with oltr, but not all. So, I try to figure out
+ * which packets should have been SR here. I'll check to
+ * see if there's a SNAP or IPX field right after
+ * my RIF fields.
+ */
+ else if ( (
+ pd[offset + 0x0e + trn_rif_bytes] == 0xaa &&
+ pd[offset + 0x0f + trn_rif_bytes] == 0xaa &&
+ pd[offset + 0x10 + trn_rif_bytes] == 0x03) ||
+ (
+ pd[offset + 0x0e + trn_rif_bytes] == 0xe0 &&
+ pd[offset + 0x0f + trn_rif_bytes] == 0xe0) ) {
+
+ source_routed = 1;
+ }
+
}
-}
-static int
-sr_frame(u_char val) {
+ if (source_routed) {
+ actual_rif_bytes = trn_rif_bytes;
+ }
+ else {
+ trn_rif_bytes = 0;
+ actual_rif_bytes = 0;
+ }
- int rc_frame[7] = { 516, 1500, 2052, 4472, 8144, 11407, 17800 };
+ /* this is a silly hack for Linux 2.0.x. Read the comment below,
+ in front of the other #ifdef linux. If we're sniffing our own NIC,
+ we get a full RIF, sometimes with garbage */
+ if ((source_routed && trn_rif_bytes == 2 && frame_type == 1) ||
+ (!source_routed && frame_type == 1)) {
+ /* look for SNAP or IPX only */
+ if ( (pd[offset + 0x20] == 0xaa && pd[offset + 0x21] == 0xaa && pd[offset + 0x22] == 03) ||
+ (pd[offset + 0x20] == 0xe0 && pd[offset + 0x21] == 0xe0) ) {
+ actual_rif_bytes = 18;
+ } else if (
+ pd[offset + 0x23] == 0 &&
+ pd[offset + 0x24] == 0 &&
+ pd[offset + 0x25] == 0 &&
+ pd[offset + 0x26] == 0x00 &&
+ pd[offset + 0x27] == 0x11) {
+
+ actual_rif_bytes = 18;
+
+ /* Linux 2.0.x also requires drivers pass up a fake SNAP and LLC header before th
+ real LLC hdr for all Token Ring frames that arrive with DSAP and SSAP != 0xAA
+ (i.e. for non SNAP frames e.g. for Netware frames)
+ the fake SNAP header has the ETH_P_TR_802_2 ether type (0x0011) and the protocol id
+ bytes as zero frame looks like :-
+ TR Header | Fake LLC | Fake SNAP | Wire LLC | Rest of data */
+ offset += 8; /* Skip fake LLC and SNAP */
+ }
+ }
+
+ offset += actual_rif_bytes + 14;
- if (val > 6) {
- return -1;
+ /* The package is either MAC or LLC */
+ switch (frame_type) {
+ /* MAC */
+ case 0:
+ ld->other++;
+ break;
+ case 1:
+ capture_llc(pd, offset, cap_len, ld);
+ break;
+ default:
+ /* non-MAC, non-LLC, i.e., "Reserved" */
+ ld->other++;
+ break;
}
- else return rc_frame[val];
}
void
-dissect_tr(const u_char *pd, frame_data *fd, GtkTree *tree) {
-
- GtkWidget *fh_tree, *ti;
- int offset = 14;
+dissect_tr(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
+ proto_tree *tr_tree, *bf_tree;
+ proto_item *ti;
+ int fixoffset = 0;
int source_routed = 0;
int frame_type;
- guint8 trn_rif_bytes;
- guint8 actual_rif_bytes;
+ guint8 trn_rif_bytes;
+ guint8 actual_rif_bytes;
/* The trn_hdr struct, as separate variables */
guint8 trn_ac; /* access control field */
guint16 trn_rseg[8]; /* routing registers */
/* non-source-routed version of source addr */
- guint8 trn_shost_nonsr[6];
+ static guint8 trn_shost_nonsr[6];
+ int x;
+
+ /* Token-Ring Strings */
+ char *fc[] = { "MAC", "LLC", "Reserved", "Unknown" };
+ if (fd->cap_len < TR_MIN_HEADER_LEN) {
+ dissect_data(pd, offset, fd, tree);
+ return;
+ }
+
+ if ((x = check_for_old_linux(pd)))
+ {
+ /* Actually packet starts x bytes into what we have got but with all
+ source routing compressed. See comment above */
+ offset += x;
+ /* pd = &pd[x]; */
+ }
- /* Token-Ring Strings */
- char *fc[] = { "MAC", "LLC", "Reserved" };
- char *fc_pcf[] = {
- "Normal buffer", "Express buffer", "Purge",
- "Claim Token", "Beacon", "Active Monitor Present",
- "Standby Monitor Present" };
- char *rc_arrow[] = { "-->", "<--" };
- char *rc_direction[] = { "From originating station",
- "To originating station" };
/* get the data */
- memcpy(&trn_ac, &pd[0], sizeof(guint8));
- memcpy(&trn_fc, &pd[1], sizeof(guint8));
- memcpy(trn_dhost, &pd[2], 6 * sizeof(guint8));
- memcpy(trn_shost, &pd[8], 6 * sizeof(guint8));
- memcpy(&trn_rcf, &pd[14], sizeof(guint16));
- memcpy(trn_rseg, &pd[16], 8 * sizeof(guint16));
-
- memcpy(trn_shost_nonsr, &pd[8], 6 * sizeof(guint8));
+ memcpy(&trn_ac, &pd[offset+0], sizeof(guint8));
+ memcpy(&trn_fc, &pd[offset+1], sizeof(guint8));
+ memcpy(trn_dhost, &pd[offset+2], 6 * sizeof(guint8));
+ memcpy(trn_shost, &pd[offset+8], 6 * sizeof(guint8));
+ memcpy(&trn_rcf, &pd[offset+14], sizeof(guint16));
+ memcpy(trn_rseg, &pd[offset+16], 8 * sizeof(guint16));
+
+ memcpy(trn_shost_nonsr, &pd[offset+8], 6 * sizeof(guint8));
trn_shost_nonsr[0] &= 127;
frame_type = (trn_fc & 192) >> 6;
this packet is source-routed */
source_routed = trn_shost[0] & 128;
- trn_rif_bytes = pd[14] & 31;
+ trn_rif_bytes = pd[offset+14] & 31;
/* sometimes we have a RCF but no RIF... half source-routed? */
/* I'll check for 2 bytes of RIF and the 0x70 byte */
- if (!source_routed) {
+ if (!source_routed && trn_rif_bytes > 0) {
if (trn_rif_bytes == 2) {
source_routed = 1;
}
* my RIF fields.
*/
else if ( (
- pd[0x0e + trn_rif_bytes] == 0xaa &&
- pd[0x0f + trn_rif_bytes] == 0xaa &&
- pd[0x10 + trn_rif_bytes] == 0x03) ||
+ pd[offset + 0x0e + trn_rif_bytes] == 0xaa &&
+ pd[offset + 0x0f + trn_rif_bytes] == 0xaa &&
+ pd[offset + 0x10 + trn_rif_bytes] == 0x03) ||
(
- pd[0x0e + trn_rif_bytes] == 0xe0 &&
- pd[0x0f + trn_rif_bytes] == 0xe0) ) {
+ pd[offset + 0x0e + trn_rif_bytes] == 0xe0 &&
+ pd[offset + 0x0f + trn_rif_bytes] == 0xe0) ) {
source_routed = 1;
}
/* else {
- printf("0e+%d = %02X 0f+%d = %02X\n", trn_rif_bytes, pd[0x0e + trn_rif_bytes],
- trn_rif_bytes, pd[0x0f + trn_rif_bytes]);
+ printf("0e+%d = %02X 0f+%d = %02X\n", trn_rif_bytes,
+ pd[offset + 0x0e + trn_rif_bytes],
+ trn_rif_bytes,
+ pd[offset + 0x0f + trn_rif_bytes]);
} */
}
if ((source_routed && trn_rif_bytes == 2 && frame_type == 1) ||
(!source_routed && frame_type == 1)) {
/* look for SNAP or IPX only */
- if ( (pd[0x20] == 0xaa && pd[0x21] == 0xaa && pd[0x22] == 03) ||
- (pd[0x20] == 0xe0 && pd[0x21] == 0xe0) ) {
+ if ( (pd[offset + 0x20] == 0xaa &&
+ pd[offset + 0x21] == 0xaa &&
+ pd[offset + 0x22] == 03)
+ ||
+ (pd[offset + 0x20] == 0xe0 &&
+ pd[offset + 0x21] == 0xe0) ) {
+
actual_rif_bytes = 18;
- }
+ }
+ else if (
+ pd[0x23] == 0 &&
+ pd[0x24] == 0 &&
+ pd[0x25] == 0 &&
+ pd[0x26] == 0x00 &&
+ pd[0x27] == 0x11) {
+
+ actual_rif_bytes = 18;
+
+ /* Linux 2.0.x also requires drivers pass up a fake SNAP and LLC header before th
+ real LLC hdr for all Token Ring frames that arrive with DSAP and SSAP != 0xAA
+ (i.e. for non SNAP frames e.g. for Netware frames)
+ the fake SNAP header has the ETH_P_TR_802_2 ether type (0x0011) and the protocol id
+ bytes as zero frame looks like :-
+ TR Header | Fake LLC | Fake SNAP | Wire LLC | Rest of data */
+ fixoffset += 8; /* Skip fake LLC and SNAP */
+ }
}
- offset += actual_rif_bytes;
+ /* XXX - copy it to some buffer associated with "pi", rather than
+ just making "trn_shost_nonsr" static? */
+ SET_ADDRESS(&pi.dl_src, AT_ETHER, 6, &trn_shost_nonsr[0]);
+ SET_ADDRESS(&pi.src, AT_ETHER, 6, &trn_shost_nonsr[0]);
+ SET_ADDRESS(&pi.dl_dst, AT_ETHER, 6, &pd[offset + 2]);
+ SET_ADDRESS(&pi.dst, AT_ETHER, 6, &pd[offset + 2]);
/* information window */
- if (fd->win_info[COL_NUM]) {
- strcpy(fd->win_info[COL_DESTINATION], ether_to_str((guint8 *)&pd[2]));
- strcpy(fd->win_info[COL_SOURCE], ether_to_str(trn_shost_nonsr));
- strcpy(fd->win_info[COL_PROTOCOL], "TR");
- sprintf(fd->win_info[COL_INFO], "Token-Ring %s", fc[frame_type]);
- }
+ if (check_col(fd, COL_PROTOCOL))
+ col_add_str(fd, COL_PROTOCOL, "TR");
+ if (check_col(fd, COL_INFO))
+ col_add_fstr(fd, COL_INFO, "Token-Ring %s", fc[frame_type]);
/* protocol analysis tree */
if (tree) {
- ti = add_item_to_tree(GTK_WIDGET(tree), 0, 14 + actual_rif_bytes,
- "Token-Ring");
- fh_tree = gtk_tree_new();
- add_subtree(ti, fh_tree, ETT_TOKEN_RING);
- add_item_to_tree(fh_tree, 0, 1,
- "Access Control: %s, Priority=%d, Monitor Count=%d, "
- "Priority Reservation=%d",
- ((trn_ac & 16) >> 4) ? "Frame" : "Token", /* frame/token */
- ((trn_ac & 224) >> 5), /* priority */
- ((trn_ac & 8) >> 3), /* monitor count */
- ((trn_ac & 7))); /* priority reserv. */
-
- add_item_to_tree(fh_tree, 1, 1,
- "Frame Control: %s, Physical Control=%d (%s)",
- fc[frame_type], (trn_fc & 15),
- fc_pcf[(trn_fc & 15)]);
-
- add_item_to_tree(fh_tree, 2, 6, "Destination: %s",
- ether_to_str((guint8 *) trn_dhost));
- add_item_to_tree(fh_tree, 8, 6, "Source: %s",
- ether_to_str((guint8 *) trn_shost));
+ /* Create Token-Ring Tree */
+ ti = proto_tree_add_item(tree, proto_tr, offset, 14 + actual_rif_bytes, NULL);
+ tr_tree = proto_item_add_subtree(ti, ett_token_ring);
- if (source_routed) {
- add_item_to_tree(fh_tree, 14, 1, "RIF length: %d bytes", trn_rif_bytes);
+ /* Create the Access Control bitfield tree */
+ ti = proto_tree_add_item(tr_tree, hf_tr_ac, offset, 1, trn_ac);
+ bf_tree = proto_item_add_subtree(ti, ett_token_ring_ac);
- add_item_to_tree(fh_tree, 15, 1,
- "%s, up to %d bytes in frame (LF=%d)",
- sr_broadcast((pd[14] & 224) >> 5),
- sr_frame((pd[15] & 112) >> 4),
- (pd[15] & 112) >> 4);
+ proto_tree_add_item(bf_tree, hf_tr_priority, offset, 1, trn_ac);
+ proto_tree_add_item(bf_tree, hf_tr_frame, offset, 1, trn_ac);
+ proto_tree_add_item(bf_tree, hf_tr_monitor_cnt, offset, 1, trn_ac);
+ proto_tree_add_item(bf_tree, hf_tr_priority_reservation, offset, 1, trn_ac);
- add_item_to_tree(fh_tree, 15, 1,
- "Direction: %s (%s)",
- rc_direction[(pd[15] & 128) >> 7],
- rc_arrow[(pd[15] & 128) >> 7]);
+ /* Create the Frame Control bitfield tree */
+ ti = proto_tree_add_item(tr_tree, hf_tr_fc, offset + 1, 1, trn_fc);
+ bf_tree = proto_item_add_subtree(ti, ett_token_ring_fc);
+
+ proto_tree_add_item(bf_tree, hf_tr_fc_type, offset + 1, 1, trn_fc);
+ proto_tree_add_item(bf_tree, hf_tr_fc_pcf, offset + 1, 1, trn_fc);
+ proto_tree_add_item(tr_tree, hf_tr_dst, offset + 2, 6, trn_dhost);
+ proto_tree_add_item(tr_tree, hf_tr_src, offset + 8, 6, trn_shost);
+
+ proto_tree_add_item_hidden(tr_tree, hf_tr_sr, offset + 8, 1, source_routed);
+
+ /* non-source-routed version of src addr */
+ proto_tree_add_item_hidden(tr_tree, hf_tr_src, offset + 8, 6, trn_shost_nonsr);
+
+ if (source_routed) {
+ /* RCF Byte 1 */
+ proto_tree_add_item(tr_tree, hf_tr_rif_bytes, offset + 14, 1, trn_rif_bytes);
+ proto_tree_add_item(tr_tree, hf_tr_broadcast, offset + 14, 1, pd[offset + 14] & 224);
+
+ /* RCF Byte 2 */
+ proto_tree_add_item(tr_tree, hf_tr_max_frame_size, offset + 15, 1, pd[offset + 15] & 112);
+ proto_tree_add_item(tr_tree, hf_tr_direction, offset + 15, 1, pd[offset + 15] & 128);
/* if we have more than 2 bytes of RIF, then we have
ring/bridge pairs */
- if (trn_rif_bytes > 2) {
- add_ring_bridge_pairs(trn_rif_bytes, pd, fh_tree);
+ if ((trn_rif_bytes > 2) && BYTES_ARE_IN_FRAME(offset + 14, trn_rif_bytes)) {
+ add_ring_bridge_pairs(trn_rif_bytes,
+ pd, offset, tr_tree);
}
}
tcpdump. W/o that, however, I'm guessing that DSAP == SSAP if the
frame type is LLC. It's very much a hack. -- Gilbert Ramirez */
if (actual_rif_bytes > trn_rif_bytes) {
- /*printf("trn_rif %d actual_rif %d\n", trn_rif_bytes, actual_rif_bytes);*/
- add_item_to_tree(fh_tree, 14 + trn_rif_bytes, actual_rif_bytes - trn_rif_bytes,
+ proto_tree_add_text(tr_tree, 14 + trn_rif_bytes, actual_rif_bytes - trn_rif_bytes,
"Empty RIF from Linux 2.0.x driver. The sniffing NIC "
"is also running a protocol stack.");
}
- /*
- if (source_routed && (trn_rif_bytes == 2) && silly_linux) {
- add_item_to_tree(fh_tree, 14 + trn_rif_bytes, 18 - actual_rif_bytes,
- "Empty RIF from Linux 2.0.x driver. The sniffing NIC "
- "is also running a protocol stack.");
+ if (fixoffset) {
+ proto_tree_add_text(tr_tree, 14 + 18,8,"Linux 2.0.x fake LLC and SNAP header");
}
- else if ((!source_routed) && silly_linux ) {
- add_item_to_tree(fh_tree, 14, 18,
- "Empty RIF from Linux 2.0.x driver. The sniffing NIC "
- "is also running a protocol stack.");
- }*/
}
-
- /* The package is either MAC or LLC */
- switch (frame_type) {
- /* MAC */
- case 0:
- dissect_trmac(pd, offset, fd, tree);
- break;
- case 1:
- dissect_llc(pd, offset, fd, tree);
- break;
- default:
- /* non-MAC, non-LLC, i.e., "Reserved" */
- dissect_data(pd, offset, fd, tree);
- break;
+ offset += 14 + actual_rif_bytes + fixoffset;
+
+ if (IS_DATA_IN_FRAME(offset)) {
+ /* The package is either MAC or LLC */
+ switch (frame_type) {
+ /* MAC */
+ case 0:
+ dissect_trmac(pd, offset, fd, tree);
+ break;
+ case 1:
+ dissect_llc(pd, offset, fd, tree);
+ break;
+ default:
+ /* non-MAC, non-LLC, i.e., "Reserved" */
+ dissect_data(pd, offset, fd, tree);
+ break;
+ }
}
}
/* this routine is taken from the Linux net/802/tr.c code, which shows
-ring-bridge paires in the /proc/net/tr_rif virtual file. */
+ring-bridge pairs in the /proc/net/tr_rif virtual file. */
static void
-add_ring_bridge_pairs(int rcf_len, const u_char *pd, GtkWidget *tree)
+add_ring_bridge_pairs(int rcf_len, const u_char *pd, int offset, proto_tree *tree)
{
int j, size;
- int segment, brdgnmb;
- char buffer[50];
- int buff_offset=0;
+ int segment, brdgnmb, unprocessed_rif;
+ int buff_offset=0;
- rcf_len -= 2;
+#define RIF_BYTES_TO_PROCESS 30
- if (rcf_len)
- rcf_len >>= 1;
+ char buffer[3 + (RIF_BYTES_TO_PROCESS / 2) * 6 + 1];
- for(j = 1; j < rcf_len; j++) {
+ /* Only process so many bytes of RIF, as per TR spec, and not overflow
+ * static buffer above */
+ unprocessed_rif = rcf_len - RIF_BYTES_TO_PROCESS;
+ rcf_len = MIN(rcf_len, RIF_BYTES_TO_PROCESS);
+
+ /* Ignore the 2 RCF bytes, since they don't make up the ring/bride pairs */
+ rcf_len -= 2;
+
+ for(j = 1; j < rcf_len - 1; j += 2) {
if (j==1) {
- segment=ntohs(*((unsigned short*)&pd[16])) >> 4;
- size = sprintf(buffer,"%03X",segment);
+ segment=pntohs(&pd[offset + 16]) >> 4;
+ size = sprintf(buffer, "%03X",segment);
+ proto_tree_add_item_hidden(tree, hf_tr_rif_ring, offset + 16, 2, segment);
buff_offset += size;
}
- segment=ntohs(*((unsigned short*)&pd[17+j])) >> 4;
- brdgnmb=pd[16+j] & 0x0f;
- size = sprintf(buffer+buff_offset,"-%01X-%03X",brdgnmb,segment);
+ segment=pntohs(&pd[offset+17+j]) >> 4;
+ brdgnmb=pd[offset+16+j] & 0x0f;
+ size = sprintf(buffer+buff_offset, "-%01X-%03X",brdgnmb,segment);
+ proto_tree_add_item_hidden(tree, hf_tr_rif_ring, offset+17+j, 2, segment);
+ proto_tree_add_item_hidden(tree, hf_tr_rif_bridge, offset+16+j, 1, brdgnmb);
buff_offset += size;
}
+ proto_tree_add_item(tree, hf_tr_rif, offset+16, rcf_len, buffer);
- add_item_to_tree(tree, 16, rcf_len << 1,
- "Ring-Bridge Pairs: %s",
- buffer);
+ if (unprocessed_rif > 0) {
+ proto_tree_add_text(tree, offset+14+RIF_BYTES_TO_PROCESS, unprocessed_rif,
+ "Extra RIF bytes beyond spec: %d", unprocessed_rif);
+ }
+}
+void
+proto_register_tr(void)
+{
+ static hf_register_info hf[] = {
+ { &hf_tr_ac,
+ { "Access Control", "tr.ac", FT_UINT8, BASE_HEX, NULL, 0x0,
+ "" }},
+
+ { &hf_tr_priority,
+ { "Priority", "tr.priority", FT_UINT8, BASE_DEC, NULL, 0xe0,
+ "" }},
+
+ { &hf_tr_frame,
+ { "Frame", "tr.frame", FT_BOOLEAN, 8, TFS(&ac_truth), 0x10,
+ "" }},
+
+ { &hf_tr_monitor_cnt,
+ { "Monitor Count", "tr.monitor_cnt", FT_UINT8, BASE_DEC, NULL, 0x08,
+ "" }},
+
+ { &hf_tr_priority_reservation,
+ { "Priority Reservation","tr.priority_reservation", FT_UINT8, BASE_DEC, NULL, 0x07,
+ "" }},
+
+ { &hf_tr_fc,
+ { "Frame Control", "tr.fc", FT_UINT8, BASE_HEX, NULL, 0x0,
+ "" }},
+
+ { &hf_tr_fc_type,
+ { "Frame Type", "tr.frame_type", FT_UINT8, BASE_DEC, VALS(frame_vals), 0xc0,
+ "" }},
+
+ { &hf_tr_fc_pcf,
+ { "Frame PCF", "tr.frame_pcf", FT_UINT8, BASE_DEC, VALS(pcf_vals), 0x0f,
+ "" }},
+
+ { &hf_tr_dst,
+ { "Destination", "tr.dst", FT_ETHER, BASE_NONE, NULL, 0x0,
+ "Destination Hardware Address" }},
+
+ { &hf_tr_src,
+ { "Source", "tr.src", FT_ETHER, BASE_NONE, NULL, 0x0,
+ "Source Hardware Address" }},
+
+ { &hf_tr_sr,
+ { "Source Routed", "tr.sr", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Source Routed" }},
+
+ { &hf_tr_rif_bytes,
+ { "RIF Bytes", "tr.rif_bytes", FT_UINT8, BASE_DEC, NULL, 0x0,
+ "Number of bytes in Routing Information Fields, including "
+ "the two bytes of Routing Control Field" }},
+
+ { &hf_tr_broadcast,
+ { "Broadcast Type", "tr.broadcast", FT_UINT8, BASE_DEC, VALS(broadcast_vals), 0x0,
+ "Type of Token-Ring Broadcast" }},
+
+ { &hf_tr_max_frame_size,
+ { "Maximum Frame Size", "tr.max_frame_size", FT_UINT8, BASE_DEC, VALS(max_frame_size_vals),
+ 0x0,
+ "" }},
+
+ { &hf_tr_direction,
+ { "Direction", "tr.direction", FT_UINT8, BASE_DEC, VALS(direction_vals), 0x0,
+ "Direction of RIF" }},
+
+ { &hf_tr_rif,
+ { "Ring-Bridge Pairs", "tr.rif", FT_STRING, BASE_NONE, NULL, 0x0,
+ "String representing Ring-Bridge Pairs" }},
+
+ { &hf_tr_rif_ring,
+ { "RIF Ring", "tr.rif.ring", FT_UINT16, BASE_HEX, NULL, 0x0,
+ "" }},
+
+ { &hf_tr_rif_bridge,
+ { "RIF Bridge", "tr.rif.bridge", FT_UINT8, BASE_HEX, NULL, 0x0,
+ "" }},
+ };
+ static gint *ett[] = {
+ &ett_token_ring,
+ &ett_token_ring_ac,
+ &ett_token_ring_fc,
+ };
+
+ proto_tr = proto_register_protocol("Token-Ring", "tr");
+ proto_register_field_array(proto_tr, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
}
git.samba.org / obnox / wireshark / wip.git / blobdiff