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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:34:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:34:10 +0000
commite4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc (patch)
tree68cb5ef9081156392f1dd62a00c6ccc1451b93df /epan/dissectors/packet-chdlc.c
parentInitial commit. (diff)
downloadwireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.tar.xz
wireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.zip
Adding upstream version 4.2.2.upstream/4.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'epan/dissectors/packet-chdlc.c')
-rw-r--r--epan/dissectors/packet-chdlc.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/epan/dissectors/packet-chdlc.c b/epan/dissectors/packet-chdlc.c
new file mode 100644
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+++ b/epan/dissectors/packet-chdlc.c
@@ -0,0 +1,405 @@
+/* packet-chdlc.c
+ * Routines for Cisco HDLC packet disassembly
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/capture_dissectors.h>
+#include <wsutil/pint.h>
+#include <epan/etypes.h>
+#include <epan/prefs.h>
+#include <epan/chdlctypes.h>
+#include <epan/nlpid.h>
+#include <epan/addr_resolv.h>
+#include "packet-chdlc.h"
+#include "packet-ppp.h"
+#include "packet-ip.h"
+#include "packet-juniper.h"
+#include "packet-l2tp.h"
+#include <epan/expert.h>
+
+/*
+ * See section 4.3.1 of RFC 1547, and
+ *
+ * http://www.nethelp.no/net/cisco-hdlc.txt
+ */
+
+void proto_register_chdlc(void);
+void proto_reg_handoff_chdlc(void);
+void proto_register_slarp(void);
+void proto_reg_handoff_slarp(void);
+
+static int proto_chdlc = -1;
+static int hf_chdlc_addr = -1;
+static int hf_chdlc_control = -1;
+static int hf_chdlc_proto = -1;
+static int hf_chdlc_clns_padding = -1;
+
+static gint ett_chdlc = -1;
+
+static int proto_slarp = -1;
+static int hf_slarp_ptype = -1;
+static int hf_slarp_address = -1;
+static int hf_slarp_netmask = -1;
+static int hf_slarp_mysequence = -1;
+static int hf_slarp_yoursequence = -1;
+static int hf_slarp_reliability = -1;
+
+static expert_field ei_slarp_reliability = EI_INIT;
+static gint ett_slarp = -1;
+
+/*
+ * Protocol types for the Cisco HDLC format.
+ *
+ * As per the above, according to RFC 1547, these are "standard 16 bit
+ * Ethernet protocol type code[s]", but 0x8035 is Reverse ARP, and
+ * that is (at least according to the Linux ISDN code) not the
+ * same as Cisco SLARP.
+ *
+ * In addition, 0x2000 is apparently the Cisco Discovery Protocol, but
+ * on Ethernet those are encapsulated inside SNAP with an OUI of
+ * OUI_CISCO, not OUI_ENCAP_ETHER.
+ *
+ * We thus have a separate dissector table for Cisco HDLC types.
+ * We could perhaps have that table hold only type values that
+ * wouldn't be in the Ethernet dissector table, and check that
+ * table first and the Ethernet dissector table if that fails.
+ */
+#define CISCO_SLARP 0x8035 /* Cisco SLARP protocol */
+
+static dissector_table_t subdissector_table;
+
+static dissector_handle_t chdlc_handle;
+
+static capture_dissector_handle_t ip_cap_handle;
+
+static const value_string chdlc_address_vals[] = {
+ {CHDLC_ADDR_UNICAST, "Unicast"},
+ {CHDLC_ADDR_MULTICAST, "Multicast"},
+ {0, NULL}
+};
+
+const value_string chdlc_vals[] = {
+ {0x2000, "Cisco Discovery Protocol"},
+ {ETHERTYPE_IP, "IP"},
+ {ETHERTYPE_IPv6, "IPv6"},
+ {CISCO_SLARP, "SLARP"},
+ {ETHERTYPE_DEC_LB, "DEC LanBridge"},
+ {CHDLCTYPE_BPDU, "Spanning Tree BPDU"},
+ {ETHERTYPE_ATALK, "Appletalk"},
+ {ETHERTYPE_AARP, "AARP"},
+ {ETHERTYPE_IPX, "Netware IPX/SPX"},
+ {ETHERTYPE_ETHBRIDGE, "Transparent Ethernet bridging" },
+ {CHDLCTYPE_OSI, "OSI" },
+ {ETHERTYPE_MPLS, "MPLS unicast"},
+ {ETHERTYPE_MPLS_MULTI, "MPLS multicast"},
+ {0, NULL}
+};
+
+static gboolean
+capture_chdlc( const guchar *pd, int offset, int len, capture_packet_info_t *cpinfo, const union wtap_pseudo_header *pseudo_header) {
+ if (!BYTES_ARE_IN_FRAME(offset, len, 4))
+ return FALSE;
+
+ switch (pntoh16(&pd[offset + 2])) {
+ case ETHERTYPE_IP:
+ return call_capture_dissector(ip_cap_handle, pd, offset + 4, len, cpinfo, pseudo_header);
+ }
+
+ return FALSE;
+}
+
+void
+chdlctype(dissector_handle_t sub_dissector, guint16 chdlc_type,
+ tvbuff_t *tvb, int offset_after_chdlctype,
+ packet_info *pinfo, proto_tree *tree, proto_tree *fh_tree,
+ int chdlctype_id)
+{
+ tvbuff_t *next_tvb;
+ int padbyte;
+
+ proto_tree_add_uint(fh_tree, chdlctype_id, tvb,
+ offset_after_chdlctype - 2, 2, chdlc_type);
+
+ padbyte = tvb_get_guint8(tvb, offset_after_chdlctype);
+ if (chdlc_type == CHDLCTYPE_OSI &&
+ !( padbyte == NLPID_ISO8473_CLNP || /* older Juniper SW does not send a padbyte */
+ padbyte == NLPID_ISO9542_ESIS ||
+ padbyte == NLPID_ISO10589_ISIS)) {
+ /* There is a Padding Byte for CLNS protocols over Cisco HDLC */
+ proto_tree_add_item(fh_tree, hf_chdlc_clns_padding, tvb, offset_after_chdlctype, 1, ENC_BIG_ENDIAN);
+ next_tvb = tvb_new_subset_remaining(tvb, offset_after_chdlctype + 1);
+ } else {
+ next_tvb = tvb_new_subset_remaining(tvb, offset_after_chdlctype);
+ }
+
+ /* dissect with the handle; if there's no handle, it's just data */
+ if (sub_dissector != NULL) {
+ call_dissector(sub_dissector, next_tvb, pinfo, tree);
+ } else {
+ col_add_fstr(pinfo->cinfo, COL_PROTOCOL, "0x%04x", chdlc_type);
+ call_data_dissector(next_tvb, pinfo, tree);
+ }
+}
+
+static gint chdlc_fcs_decode = 0; /* 0 = No FCS, 1 = 16 bit FCS, 2 = 32 bit FCS */
+
+static int
+dissect_chdlc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+ proto_item *ti;
+ proto_tree *fh_tree = NULL;
+ guint16 proto;
+ dissector_handle_t sub_dissector;
+
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "CHDLC");
+ col_clear(pinfo->cinfo, COL_INFO);
+
+ switch (pinfo->p2p_dir) {
+
+ case P2P_DIR_SENT:
+ col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "DTE");
+ col_set_str(pinfo->cinfo, COL_RES_DL_DST, "DCE");
+ break;
+
+ case P2P_DIR_RECV:
+ col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "DCE");
+ col_set_str(pinfo->cinfo, COL_RES_DL_DST, "DTE");
+ break;
+
+ default:
+ col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "N/A");
+ col_set_str(pinfo->cinfo, COL_RES_DL_DST, "N/A");
+ break;
+ }
+
+ proto = tvb_get_ntohs(tvb, 2);
+
+ if (tree) {
+ ti = proto_tree_add_item(tree, proto_chdlc, tvb, 0, 4, ENC_NA);
+ fh_tree = proto_item_add_subtree(ti, ett_chdlc);
+
+ proto_tree_add_item(fh_tree, hf_chdlc_addr, tvb, 0, 1, ENC_NA);
+ proto_tree_add_item(fh_tree, hf_chdlc_control, tvb, 1, 1, ENC_NA);
+ }
+
+ decode_fcs(tvb, pinfo, fh_tree, chdlc_fcs_decode, 2);
+
+ sub_dissector = dissector_get_uint_handle(subdissector_table, proto);
+ chdlctype(sub_dissector, proto, tvb, 4, pinfo, tree, fh_tree, hf_chdlc_proto);
+ return tvb_captured_length(tvb);
+}
+
+void
+proto_register_chdlc(void)
+{
+ static hf_register_info hf[] = {
+ { &hf_chdlc_addr,
+ { "Address", "chdlc.address", FT_UINT8, BASE_HEX,
+ VALS(chdlc_address_vals), 0x0, NULL, HFILL }},
+ { &hf_chdlc_control,
+ { "Control", "chdlc.control", FT_UINT8, BASE_HEX,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_chdlc_proto,
+ { "Protocol", "chdlc.protocol", FT_UINT16, BASE_HEX,
+ VALS(chdlc_vals), 0x0, NULL, HFILL }},
+ { &hf_chdlc_clns_padding,
+ { "CLNS Padding", "chdlc.clns_padding", FT_UINT8, BASE_HEX,
+ NULL, 0x0, NULL, HFILL }},
+ };
+
+ static gint *ett[] = {
+ &ett_chdlc,
+ };
+
+ module_t *chdlc_module;
+
+ proto_chdlc = proto_register_protocol("Cisco HDLC", "CHDLC", "chdlc");
+ proto_register_field_array(proto_chdlc, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+
+ /* subdissector code */
+ subdissector_table = register_dissector_table("chdlc.protocol",
+ "Cisco HDLC protocol", proto_chdlc,
+ FT_UINT16, BASE_HEX);
+
+ chdlc_handle = register_dissector("chdlc", dissect_chdlc, proto_chdlc);
+
+ /* Register the preferences for the chdlc protocol */
+ chdlc_module = prefs_register_protocol(proto_chdlc, NULL);
+
+ prefs_register_enum_preference(chdlc_module,
+ "fcs_type",
+ "CHDLC Frame Checksum Type",
+ "The type of CHDLC frame checksum (none, 16-bit, 32-bit)",
+ &chdlc_fcs_decode,
+ fcs_options, ENC_BIG_ENDIAN);
+
+ register_capture_dissector("chdlc", capture_chdlc, proto_chdlc);
+
+}
+
+void
+proto_reg_handoff_chdlc(void)
+{
+ capture_dissector_handle_t chdlc_cap_handle;
+
+ dissector_add_uint("wtap_encap", WTAP_ENCAP_CHDLC, chdlc_handle);
+ dissector_add_uint("wtap_encap", WTAP_ENCAP_CHDLC_WITH_PHDR, chdlc_handle);
+ dissector_add_uint("juniper.proto", JUNIPER_PROTO_CHDLC, chdlc_handle);
+ dissector_add_uint("l2tp.pw_type", L2TPv3_PW_CHDLC, chdlc_handle);
+
+ chdlc_cap_handle = find_capture_dissector("chdlc");
+ capture_dissector_add_uint("wtap_encap", WTAP_ENCAP_CHDLC, chdlc_cap_handle);
+
+ ip_cap_handle = find_capture_dissector("ip");
+}
+
+
+
+
+#define SLARP_REQUEST 0
+#define SLARP_REPLY 1
+#define SLARP_LINECHECK 2
+
+static const value_string slarp_ptype_vals[] = {
+ {SLARP_REQUEST, "Request"},
+ {SLARP_REPLY, "Reply"},
+ {SLARP_LINECHECK, "Line keepalive"},
+ {0, NULL}
+};
+
+static int
+dissect_slarp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+ proto_item *ti;
+ proto_tree *slarp_tree;
+ guint32 code;
+ guint32 addr;
+ guint32 mysequence;
+ guint32 yoursequence;
+ proto_item* reliability_item;
+
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "SLARP");
+ col_clear(pinfo->cinfo, COL_INFO);
+
+ code = tvb_get_ntohl(tvb, 0);
+
+ ti = proto_tree_add_item(tree, proto_slarp, tvb, 0, 14, ENC_NA);
+ slarp_tree = proto_item_add_subtree(ti, ett_slarp);
+
+ switch (code) {
+
+ case SLARP_REQUEST:
+ case SLARP_REPLY:
+ addr = tvb_get_ipv4(tvb, 4);
+ col_add_fstr(pinfo->cinfo, COL_INFO, "%s, from %s, mask %s",
+ val_to_str(code, slarp_ptype_vals, "Unknown (%d)"),
+ get_hostname(addr), tvb_ip_to_str(pinfo->pool, tvb, 8));
+ if (tree) {
+ proto_tree_add_uint(slarp_tree, hf_slarp_ptype, tvb, 0, 4, code);
+ proto_tree_add_item(slarp_tree, hf_slarp_address, tvb, 4, 4, ENC_BIG_ENDIAN);
+ proto_tree_add_item(slarp_tree, hf_slarp_netmask, tvb, 8, 4, ENC_BIG_ENDIAN);
+ }
+ break;
+
+ case SLARP_LINECHECK:
+ mysequence = tvb_get_ntohl(tvb, 4);
+ yoursequence = tvb_get_ntohl(tvb, 8);
+ col_add_fstr(pinfo->cinfo, COL_INFO,
+ "%s, outgoing sequence %u, returned sequence %u",
+ val_to_str(code, slarp_ptype_vals, "Unknown (%d)"),
+ mysequence, yoursequence);
+
+ proto_tree_add_uint(slarp_tree, hf_slarp_ptype, tvb, 0, 4, code);
+ proto_tree_add_uint(slarp_tree, hf_slarp_mysequence, tvb, 4, 4,
+ mysequence);
+ proto_tree_add_uint(slarp_tree, hf_slarp_yoursequence, tvb, 8, 4,
+ yoursequence);
+ reliability_item = proto_tree_add_item(slarp_tree, hf_slarp_reliability, tvb,
+ 12, 2, ENC_BIG_ENDIAN);
+ if (tvb_get_ntohs(tvb, 12) != 0xFFFF) {
+ expert_add_info(pinfo, reliability_item, &ei_slarp_reliability);
+ }
+ break;
+
+ default:
+ col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown packet type 0x%08X", code);
+
+ proto_tree_add_uint(slarp_tree, hf_slarp_ptype, tvb, 0, 4, code);
+ call_data_dissector(tvb_new_subset_remaining(tvb, 4), pinfo, slarp_tree);
+ break;
+ }
+ return tvb_captured_length(tvb);
+}
+
+void
+proto_register_slarp(void)
+{
+ expert_module_t* expert_slarp;
+
+ static hf_register_info hf[] = {
+ { &hf_slarp_ptype,
+ { "Packet type", "slarp.ptype", FT_UINT32, BASE_DEC,
+ VALS(slarp_ptype_vals), 0x0, NULL, HFILL }},
+ { &hf_slarp_address,
+ { "Address", "slarp.address", FT_IPv4, BASE_NONE,
+ NULL, 0x0, NULL, HFILL }},
+ /* XXX - need an FT_ for netmasks, which is like FT_IPV4 but doesn't
+ get translated to a host name. */
+ { &hf_slarp_netmask,
+ { "Netmask", "slarp.netmask", FT_IPv4, BASE_NETMASK,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_slarp_mysequence,
+ { "Outgoing sequence number", "slarp.mysequence", FT_UINT32, BASE_DEC,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_slarp_yoursequence,
+ { "Returned sequence number", "slarp.yoursequence", FT_UINT32, BASE_DEC,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_slarp_reliability,
+ { "Reliability", "slarp.reliability", FT_UINT16, BASE_HEX,
+ NULL, 0x0, NULL, HFILL }},
+ };
+ static gint *ett[] = {
+ &ett_slarp,
+ };
+
+ static ei_register_info ei[] = {
+ { &ei_slarp_reliability, { "slarp.reliability.invalid", PI_MALFORMED, PI_ERROR,
+ "Reliability must be 0xFFFF", EXPFILL }}
+ };
+
+ proto_slarp = proto_register_protocol("Cisco SLARP", "SLARP", "slarp");
+ register_dissector("slarp", dissect_slarp, proto_slarp);
+ proto_register_field_array(proto_slarp, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+
+ expert_slarp = expert_register_protocol(proto_slarp);
+ expert_register_field_array(expert_slarp, ei, array_length(ei));
+}
+
+void
+proto_reg_handoff_slarp(void)
+{
+ dissector_add_uint("chdlc.protocol", CISCO_SLARP, find_dissector("slarp"));
+}
+
+/*
+ * Editor modelines - https://www.wireshark.org/tools/modelines.html
+ *
+ * Local Variables:
+ * c-basic-offset: 2
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * ex: set shiftwidth=2 tabstop=8 expandtab:
+ * :indentSize=2:tabSize=8:noTabs=true:
+ */