/* packet-llc.c
* Routines for IEEE 802.2 LLC layer
- * Gilbert Ramirez <gramirez@tivoli.com>
+ * Gilbert Ramirez <gram@xiexie.org>
*
- * $Id: packet-llc.c,v 1.20 1999/08/23 22:47:13 guy Exp $
+ * $Id: packet-llc.c,v 1.56 2000/05/11 08:15:22 gram Exp $
*
* Ethereal - Network traffic analyzer
- * By Gerald Combs <gerald@unicom.net>
+ * By Gerald Combs <gerald@zing.org>
* Copyright 1998 Gerald Combs
*
*
#include <glib.h>
#include "packet.h"
+#include "oui.h"
#include "xdlc.h"
-
+#include "etypes.h"
+#include "llcsaps.h"
+#include "packet-bpdu.h"
+#include "packet-cdp.h"
+#include "packet-cgmp.h"
+#include "packet-ip.h"
+#include "packet-ipx.h"
+#include "packet-netbios.h"
+#include "packet-osi.h"
+#include "packet-sna.h"
+#include "packet-vtp.h"
+
static int proto_llc = -1;
static int hf_llc_dsap = -1;
static int hf_llc_ssap = -1;
+static int hf_llc_dsap_ig = -1;
+static int hf_llc_ssap_cr = -1;
static int hf_llc_ctrl = -1;
static int hf_llc_type = -1;
static int hf_llc_oui = -1;
+static int hf_llc_pid = -1;
+
+static gint ett_llc = -1;
+static gint ett_llc_ctrl = -1;
-typedef void (capture_func_t)(const u_char *, int, guint32, packet_counts *);
-typedef void (dissect_func_t)(const u_char *, int, frame_data *, proto_tree *);
+static dissector_table_t subdissector_table;
-/* The SAP info is split into two tables, one value_string table and one table of sap_info. This is
- * so that the value_string can be used in the header field registration.
+typedef void (capture_func_t)(const u_char *, int, packet_counts *);
+
+/* The SAP info is split into two tables, one value_string table and one
+ * table of sap_info. This is so that the value_string can be used in the
+ * header field registration.
*/
struct sap_info {
guint8 sap;
capture_func_t *capture_func;
- dissect_func_t *dissect_func;
};
+/*
+ * Group/Individual bit, in the DSAP.
+ */
+#define DSAP_GI_BIT 0x01
+
+/*
+ * Command/Response bit, in the SSAP.
+ *
+ * The low-order bit of the SSAP apparently determines whether this
+ * is a request or a response. (RFC 1390, "Transmission of IP and
+ * ARP over FDDI Networks", says
+ *
+ * Command frames are identified by having the low order
+ * bit of the SSAP address reset to zero. Response frames
+ * have the low order bit of the SSAP address set to one.
+ *
+ * and a page I've seen seems to imply that's part of 802.2.)
+ */
+#define SSAP_CR_BIT 0x01
+
+/*
+ * Mask to extrace the SAP number from the DSAP or the SSAP.
+ */
+#define SAP_MASK 0xFE
+
+/*
+ * These are for SSAP and DSAP, wth last bit always zero.
+ * XXX - some DSAPs come in separate "individual" and "group" versions,
+ * with the last bit 0 and 1, respectively (e.g., LLC Sub-layer Management,
+ * IBM SNA Path Control, IBM Net Management), but, whilst 0xFE is
+ * the ISO Network Layer Protocol, 0xFF is the Global LSAP.
+ */
static const value_string sap_vals[] = {
- { 0x00, "NULL LSAP" },
- { 0x02, "LLC Sub-Layer Management Individual" },
- { 0x03, "LLC Sub-Layer Management Group" },
- { 0x04, "SNA Path Control Individual" },
- { 0x05, "SNA Path Control Group" },
- { 0x06, "TCP/IP" },
- { 0x08, "SNA" },
- { 0x0C, "SNA" },
- { 0x42, "Spanning Tree BPDU" },
- { 0x7F, "ISO 802.2" },
- { 0x80, "XNS" },
- { 0xAA, "SNAP" },
- { 0xBA, "Banyan Vines" },
- { 0xBC, "Banyan Vines" },
- { 0xE0, "NetWare" },
- { 0xF0, "NetBIOS" },
- { 0xF4, "IBM Net Management Individual" },
- { 0xF5, "IBM Net Management Group" },
- { 0xF8, "Remote Program Load" },
- { 0xFC, "Remote Program Load" },
- { 0xFE, "ISO Network Layer" },
- { 0xFF, "Global LSAP" },
- { 0x00, NULL }
+ { SAP_NULL, "NULL LSAP" },
+ { SAP_LLC_SLMGMT, "LLC Sub-Layer Management" },
+ { SAP_SNA_PATHCTRL, "SNA Path Control" },
+ { SAP_IP, "TCP/IP" },
+ { SAP_SNA1, "SNA" },
+ { SAP_SNA2, "SNA" },
+ { SAP_PROWAY_NM_INIT, "PROWAY (IEC955) Network Management and Initialization" },
+ { SAP_TI, "Texas Instruments" },
+ { SAP_BPDU, "Spanning Tree BPDU" },
+ { SAP_RS511, "EIA RS-511 Manufacturing Message Service" },
+#if 0
+ /* XXX - setting the group bit makes this 0x7F; is that just
+ a group version of this? */
+ { 0x7E, "ISO 8208 (X.25 over 802.2 Type 2)" },
+#endif
+ { 0x7F, "ISO 802.2" },
+ { SAP_XNS, "XNS" },
+ { SAP_NESTAR, "Nestar" },
+ { SAP_PROWAY_ASLM, "PROWAY (IEC955) Active Station List Maintenance" },
+ { SAP_ARP, "ARP" }, /* XXX - hand to "dissect_arp()"? */
+ { SAP_SNAP, "SNAP" },
+ { SAP_VINES1, "Banyan Vines" },
+ { SAP_VINES2, "Banyan Vines" },
+ { SAP_NETWARE, "NetWare" },
+ { SAP_NETBIOS, "NetBIOS" },
+ { SAP_IBMNM, "IBM Net Management" },
+ { SAP_RPL1, "Remote Program Load" },
+ { SAP_UB, "Ungermann-Bass" },
+ { SAP_RPL2, "Remote Program Load" },
+ { SAP_OSINL, "ISO Network Layer" },
+ { SAP_GLOBAL, "Global LSAP" },
+ { 0x00, NULL }
};
static struct sap_info saps[] = {
- { 0x00, NULL, NULL },
- { 0x02, NULL, NULL },
- { 0x03, NULL, NULL },
- { 0x04, NULL, NULL },
- { 0x05, NULL, NULL },
- { 0x06, capture_ip, dissect_ip },
- { 0x08, NULL, NULL },
- { 0x0C, NULL, NULL },
- { 0x42, NULL, NULL },
- { 0x7F, NULL, NULL },
- { 0x80, NULL, NULL },
- { 0xAA, NULL, NULL },
- { 0xBA, NULL, NULL },
- { 0xBC, NULL, NULL },
- { 0xE0, NULL, dissect_ipx },
- { 0xF0, capture_netbios, dissect_netbios },
- { 0xF4, NULL, NULL },
- { 0xF5, NULL, NULL },
- { 0xF8, NULL, NULL },
- { 0xFC, NULL, NULL },
- { 0xFE, NULL, dissect_osi },
- { 0xFF, NULL, NULL },
- { 0x00, NULL, NULL}
-};
-
-static const value_string llc_ctrl_vals[] = {
- { 0, "Information Transfer" },
- { 1, "Supervisory" },
- { 2, "Unknown" },
- { 3, "Unnumbered Information" },
- { 0, NULL }
+ { SAP_IP, capture_ip },
+ { SAP_NETWARE, capture_ipx },
+ { SAP_NETBIOS, capture_netbios },
+ { 0x00, NULL}
};
-static const value_string llc_oui_vals[] = {
- { 0x000000, "Encapsulated Ethernet" },
+/*
+ * See
+ *
+ * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/vlan.htm
+ *
+ * for the PIDs for VTP and DRiP that go with an OUI of OUI_CISCO.
+ */
+const value_string oui_vals[] = {
+ { OUI_ENCAP_ETHER, "Encapsulated Ethernet" },
/*
http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/113ed_cr/ibm_r/brprt1/brsrb.htm
*/
- { 0x0000f8, "Cisco 90-Compatible" },
- { 0x0000c0, "Cisco" },
- { 0x0080c2, "Bridged Frame-Relay" }, /* RFC 2427 */
- { 0, NULL }
+ { OUI_CISCO, "Cisco" },
+ { OUI_CISCO_90, "Cisco IOS 9.0 Compatible" },
+ { OUI_BFR, "Bridged Frame-Relay" }, /* RFC 2427 */
+ { OUI_ATM_FORUM, "ATM Forum" },
+ { OUI_APPLE_ATALK, "Apple (AppleTalk)" },
+ { OUI_CABLE_BPDU, "DOCSIS Spanning Tree" }, /* DOCSIS spanning tree BPDU */
+ { 0, NULL }
};
static capture_func_t *
return NULL;
}
-static dissect_func_t *
-sap_dissect_func(u_char sap) {
- int i=0;
-
- /* look for the second record where sap == 0, which should
- * be the last record
- */
- while (saps[i].sap > 0 || i == 0) {
- if (saps[i].sap == sap) {
- return saps[i].dissect_func;
- }
- i++;
- }
- return dissect_data;
-}
-
-
void
-capture_llc(const u_char *pd, int offset, guint32 cap_len, packet_counts *ld) {
+capture_llc(const u_char *pd, int offset, packet_counts *ld) {
int is_snap;
- int control;
+ guint16 control;
+ int llc_header_len;
+ guint32 oui;
guint16 etype;
capture_func_t *capture;
- is_snap = (pd[offset] == 0xAA) && (pd[offset+1] == 0xAA);
+ if (!BYTES_ARE_IN_FRAME(offset, 2)) {
+ ld->other++;
+ return;
+ }
+ is_snap = (pd[offset] == SAP_SNAP) && (pd[offset+1] == SAP_SNAP);
+ llc_header_len = 2; /* DSAP + SSAP */
/*
- * The low-order bit of the SSAP apparently determines whether this
- * is a request or a response. (RFC 1390, "Transmission of IP and
- * ARP over FDDI Networks", says
- *
- * Command frames are identified by having the low order
- * bit of the SSAP address reset to zero. Response frames
- * have the low order bit of the SSAP address set to one.
- *
- * and a page I've seen seems to imply that's part of 802.2.)
- *
- * XXX - that page also implies that LLC Type 2 always uses
- * extended operation, so we don't need to determine whether
- * it's basic or extended operation; is that the case?
+ * XXX - the page referred to in the comment above about the
+ * Command/Response bit also implies that LLC Type 2 always
+ * uses extended operation, so we don't need to determine
+ * whether it's basic or extended operation; is that the case?
*/
- control = get_xdlc_control(pd, offset+2, pd[offset+1] & 0x01, TRUE);
+ control = get_xdlc_control(pd, offset+2, pd[offset+1] & SSAP_CR_BIT,
+ TRUE);
+ llc_header_len += XDLC_CONTROL_LEN(control, TRUE);
+ if (is_snap)
+ llc_header_len += 5; /* 3 bytes of OUI, 2 bytes of protocol ID */
+ if (!BYTES_ARE_IN_FRAME(offset, llc_header_len)) {
+ ld->other++;
+ return;
+ }
if (is_snap) {
- if (control == XDLC_I || control == (XDLC_U|XDLC_UI)) {
- /*
- * Unnumbered Information - analyze it based on
- * the Ethernet packet type.
- */
- etype = (pd[offset+6] << 8) | pd[offset+7];
- offset += 8;
- capture_ethertype(etype, offset, pd, cap_len, ld);
+ oui = pd[offset+3] << 16 | pd[offset+4] << 8 | pd[offset+5];
+ if (XDLC_IS_INFORMATION(control)) {
+ etype = pntohs(&pd[offset+6]);
+ switch (oui) {
+
+ case OUI_ENCAP_ETHER:
+ case OUI_APPLE_ATALK:
+ /* No, I have no idea why Apple used
+ one of their own OUIs, rather than
+ OUI_ENCAP_ETHER, and an Ethernet
+ packet type as protocol ID, for
+ AppleTalk data packets - but used
+ OUI_ENCAP_ETHER and an Ethernet
+ packet type for AARP packets. */
+ capture_ethertype(etype, offset+8, pd,
+ ld);
+ break;
+ case OUI_CISCO:
+ capture_ethertype(etype,
+ offset + 8, pd, ld);
+ break;
+ default:
+ ld->other++;
+ break;
+ }
}
}
else {
- if (control == XDLC_I || control == (XDLC_U|XDLC_UI)) {
- /*
- * Unnumbered Information - analyze it based on
- * the DSAP.
- */
+ if (XDLC_IS_INFORMATION(control)) {
capture = sap_capture_func(pd[offset]);
/* non-SNAP */
- offset += 3;
+ offset += llc_header_len;
if (capture) {
- capture(pd, offset, cap_len, ld);
+ capture(pd, offset, ld);
}
else {
ld->other++;
dissect_llc(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
proto_tree *llc_tree = NULL;
- proto_item *ti;
+ proto_item *ti = NULL;
int is_snap;
- int control;
+ guint16 control;
+ int llc_header_len;
+ guint32 oui;
guint16 etype;
- dissect_func_t *dissect;
+ guint8 dsap;
- is_snap = (pd[offset] == 0xAA) && (pd[offset+1] == 0xAA);
+ if (!BYTES_ARE_IN_FRAME(offset, 2)) {
+ dissect_data(pd, offset, fd, tree);
+ return;
+ }
+ is_snap = (pd[offset] == SAP_SNAP) && (pd[offset+1] == SAP_SNAP);
+ llc_header_len = 2; /* DSAP + SSAP */
if (check_col(fd, COL_PROTOCOL)) {
col_add_str(fd, COL_PROTOCOL, "LLC");
}
-
+
if (tree) {
- ti = proto_tree_add_item(tree, proto_llc, offset, (is_snap ? 8 : 3), NULL);
- llc_tree = proto_item_add_subtree(ti, ETT_LLC);
- proto_tree_add_item(llc_tree, hf_llc_dsap, offset, 1, pd[offset]);
- proto_tree_add_item(llc_tree, hf_llc_ssap, offset+1, 1, pd[offset+1]);
+ ti = proto_tree_add_item(tree, proto_llc, NullTVB, offset, 0, NULL);
+ llc_tree = proto_item_add_subtree(ti, ett_llc);
+ proto_tree_add_item(llc_tree, hf_llc_dsap, NullTVB, offset,
+ 1, pd[offset] & SAP_MASK);
+ proto_tree_add_item(llc_tree, hf_llc_dsap_ig, NullTVB, offset,
+ 1, pd[offset] & DSAP_GI_BIT);
+ proto_tree_add_item(llc_tree, hf_llc_ssap, NullTVB, offset+1,
+ 1, pd[offset+1] & SAP_MASK);
+ proto_tree_add_item(llc_tree, hf_llc_ssap_cr, NullTVB, offset+1,
+ 1, pd[offset+1] & SSAP_CR_BIT);
} else
llc_tree = NULL;
/*
- * The low-order bit of the SSAP apparently determines whether this
- * is a request or a response. (RFC 1390, "Transmission of IP and
- * ARP over FDDI Networks", says
- *
- * Command frames are identified by having the low order
- * bit of the SSAP address reset to zero. Response frames
- * have the low order bit of the SSAP address set to one.
- *
- * and a page I've seen seems to imply that's part of 802.2.)
- *
- * XXX - that page also implies that LLC Type 2 always uses
- * extended operation, so we don't need to determine whether
- * it's basic or extended operation; is that the case?
+ * XXX - the page referred to in the comment above about the
+ * Command/Response bit also implies that LLC Type 2 always
+ * uses extended operation, so we don't need to determine
+ * whether it's basic or extended operation; is that the case?
*/
- control = dissect_xdlc_control(pd, offset+2, fd, llc_tree, hf_llc_ctrl,
- pd[offset+1] & 0x01, TRUE);
+ control = dissect_xdlc_control(pd, offset+2, fd, llc_tree,
+ hf_llc_ctrl, ett_llc_ctrl,
+ pd[offset+1] & SSAP_CR_BIT, TRUE);
+ llc_header_len += XDLC_CONTROL_LEN(control, TRUE);
+ if (is_snap)
+ llc_header_len += 5; /* 3 bytes of OUI, 2 bytes of protocol ID */
+ if (!BYTES_ARE_IN_FRAME(offset, llc_header_len)) {
+ dissect_data(pd, offset, fd, tree);
+ return;
+ }
+ if (tree)
+ proto_item_set_len(ti, llc_header_len);
/*
* XXX - do we want to append the SAP information to the stuff
* than overwriting it?
*/
if (is_snap) {
+ oui = pd[offset+3] << 16 | pd[offset+4] << 8 | pd[offset+5];
+ etype = pntohs(&pd[offset+6]);
if (check_col(fd, COL_INFO)) {
- col_add_str(fd, COL_INFO, "802.2 LLC (SNAP)");
+ col_add_fstr(fd, COL_INFO, "SNAP, OUI 0x%06X (%s), PID 0x%04X",
+ oui, val_to_str(oui, oui_vals, "Unknown"),
+ etype);
}
if (tree) {
- proto_tree_add_item(llc_tree, hf_llc_oui, offset+3, 3,
- pd[offset+3] << 16 | pd[offset+4] << 8 | pd[offset+5]);
+ proto_tree_add_item(llc_tree, hf_llc_oui, NullTVB, offset+3, 3,
+ oui);
}
- if (control == (XDLC_U|XDLC_UI)) {
- /*
- * Unnumbered Information - dissect it based on
- * the Ethernet packet type.
- */
- etype = pntohs(&pd[offset+6]);
- offset += 8;
- /* w/o even checking, assume OUI is ethertype */
- ethertype(etype, offset, pd, fd, tree, llc_tree,
- hf_llc_type);
+ switch (oui) {
+
+ case OUI_ENCAP_ETHER:
+ case OUI_APPLE_ATALK:
+ /* No, I have no idea why Apple used
+ one of their own OUIs, rather than
+ OUI_ENCAP_ETHER, and an Ethernet
+ packet type as protocol ID, for
+ AppleTalk data packets - but used
+ OUI_ENCAP_ETHER and an Ethernet
+ packet type for AARP packets. */
+ if (XDLC_IS_INFORMATION(control)) {
+ ethertype(etype, offset+8, pd,
+ fd, tree, llc_tree, hf_llc_type);
+ } else
+ dissect_data(pd, offset+8, fd, tree);
+ break;
+
+ case OUI_CISCO:
+ /* So are all CDP packets LLC packets
+ with an OUI of OUI_CISCO and a
+ protocol ID of 0x2000, or
+ are some of them raw or encapsulated
+ Ethernet? */
+ if (tree) {
+ proto_tree_add_item(llc_tree,
+ hf_llc_pid, NullTVB, offset+6, 2, etype);
+ }
+ if (XDLC_IS_INFORMATION(control)) {
+ switch (etype) {
+
+#if 0
+ case 0x0102:
+ dissect_drip(pd, offset+8, fd, tree);
+ break;
+#endif
+
+ case 0x2000:
+ dissect_cdp(pd, offset+8, fd, tree);
+ break;
+
+ case 0x2001:
+ dissect_cgmp(pd, offset+8, fd, tree);
+ break;
+
+ case 0x2003:
+ dissect_vtp(pd, offset+8, fd, tree);
+ break;
+
+ default:
+ dissect_data(pd, offset+8, fd, tree);
+ break;
+ }
+ } else
+ dissect_data(pd, offset+8, fd, tree);
+ break;
+
+ case OUI_CABLE_BPDU: /* DOCSIS cable modem spanning tree BPDU */
+ if (tree) {
+ proto_tree_add_item(llc_tree,
+ hf_llc_pid, NullTVB, offset+6, 2, etype);
+ }
+ dissect_bpdu(pd, offset+8, fd, tree);
+ break;
+
+ default:
+ if (tree) {
+ proto_tree_add_item(llc_tree,
+ hf_llc_pid, NullTVB, offset+6, 2, etype);
+ }
+ dissect_data(pd, offset+8, fd, tree);
+ break;
}
}
else {
if (check_col(fd, COL_INFO)) {
- col_add_fstr(fd, COL_INFO, "802.2 LLC (%s)",
- val_to_str(pd[offset], sap_vals, "%02x"));
+ col_add_fstr(fd, COL_INFO,
+ "DSAP %s %s, SSAP %s %s",
+ val_to_str(pd[offset] & SAP_MASK, sap_vals, "%02x"),
+ pd[offset] & DSAP_GI_BIT ?
+ "Group" : "Individual",
+ val_to_str(pd[offset+1] & SAP_MASK, sap_vals, "%02x"),
+ pd[offset+1] & SSAP_CR_BIT ?
+ "Response" : "Command"
+ );
}
- if (control == (XDLC_U|XDLC_UI)) {
- /*
- * Unnumbered Information - dissect it based on
- * the DSAP.
- */
- dissect = sap_dissect_func(pd[offset]);
-
+ if (XDLC_IS_INFORMATION(control)) {
/* non-SNAP */
- offset += 3;
+ dsap = pd[offset];
+ offset += llc_header_len;
- if (dissect) {
- dissect(pd, offset, fd, tree);
- }
- else {
+ /* do lookup with the subdissector table */
+ if (!dissector_try_port(subdissector_table, dsap,
+ pd, offset, fd, tree)) {
dissect_data(pd, offset, fd, tree);
}
+ } else {
+ offset += llc_header_len;
+ dissect_data(pd, offset, fd, tree);
}
}
}
void
proto_register_llc(void)
{
+ static struct true_false_string ig_bit = { "Group", "Individual" };
+ static struct true_false_string cr_bit = { "Response", "Command" };
+
static hf_register_info hf[] = {
{ &hf_llc_dsap,
- { "DSAP", "llc.dsap", FT_VALS_UINT8, VALS(sap_vals) }},
+ { "DSAP", "llc.dsap", FT_UINT8, BASE_HEX,
+ VALS(sap_vals), 0x0, "" }},
+
+ { &hf_llc_dsap_ig,
+ { "IG Bit", "llc.dsap.ig", FT_BOOLEAN, BASE_HEX,
+ &ig_bit, 0x0, "Individual/Group" }},
{ &hf_llc_ssap,
- { "SSAP", "llc.ssap", FT_VALS_UINT8, VALS(sap_vals) }},
+ { "SSAP", "llc.ssap", FT_UINT8, BASE_HEX,
+ VALS(sap_vals), 0x0, "" }},
+
+ { &hf_llc_ssap_cr,
+ { "CR Bit", "llc.ssap.cr", FT_BOOLEAN, BASE_HEX,
+ &cr_bit, 0x0, "Command/Response" }},
{ &hf_llc_ctrl,
- { "Control", "llc.control", FT_VALS_UINT8, VALS(llc_ctrl_vals) }},
+ { "Control", "llc.control", FT_UINT16, BASE_HEX,
+ NULL, 0x0, "" }},
/* registered here but handled in ethertype.c */
{ &hf_llc_type,
- { "Type", "llc.type", FT_VALS_UINT16, VALS(etype_vals) }},
+ { "Type", "llc.type", FT_UINT16, BASE_HEX,
+ VALS(etype_vals), 0x0, "" }},
{ &hf_llc_oui,
- { "Organization Code", "llc.oui", FT_VALS_UINT24, VALS(llc_oui_vals) }}
+ { "Organization Code", "llc.oui", FT_UINT24, BASE_HEX,
+ VALS(oui_vals), 0x0, ""}},
+
+ { &hf_llc_pid,
+ { "Protocol ID", "llc.pid", FT_UINT16, BASE_HEX,
+ NULL, 0x0, ""}}
+ };
+ static gint *ett[] = {
+ &ett_llc,
+ &ett_llc_ctrl,
};
proto_llc = proto_register_protocol ("Logical-Link Control", "llc" );
proto_register_field_array(proto_llc, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+
+/* subdissector code */
+ subdissector_table = register_dissector_table("llc.dsap");
}
git.samba.org / metze / wireshark / wip.git / blobdiff