wireshark/epan/dissectors/packet-glbp.c

618 lines
19 KiB
C

/* packet-glbp.c
*
* Cisco's GLBP: Gateway Load Balancing Protocol
*
* Copyright 2007 Joerg Mayer (see AUTHORS file)
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
/*
* Documentation:
* http://www.cisco.com/en/US/docs/ios/12_2t/12_2t15/feature/guide/ft_glbp.pdf
*
* TODO: This dissector has been written without specs, so much of it is
* guesswork. Also, there are still unknown elements in the message.
* Some debug output:
* GLBP: Fa0/0 Grp 1020 Hello out VG Active pri 100 vIP FE80::C800:8FF:FE64:AAAA
* hello 3000, hold 10000 VF 1 Active pri 167 vMAC 0007.b403.fc01
* GLBP: Fa0/0 Grp 1021 Hello out VG Active pri 100 vIP 10.20.20.100
* hello 3000, hold 10000 VF 1 Active pri 167 vMAC 0007.b403.fd01
*/
#include "config.h"
#include <epan/packet.h>
#include <epan/expert.h>
void proto_register_glbp(void);
void proto_reg_handoff_glbp(void);
#define GLBP_UDP_PORT 3222
static int proto_glbp = -1;
/* glbp header? */
static gint hf_glbp_version = -1;
static gint hf_glbp_unknown1 = -1;
static gint hf_glbp_group = -1;
static gint hf_glbp_unknown2 = -1;
static gint hf_glbp_ownerid = -1;
static gint hf_glbp_tlv = -1;
static gint hf_glbp_type = -1;
static gint hf_glbp_length = -1;
/* glbp type = 1 - hello */
static gint hf_glbp_hello_unknown10 = -1;
static gint hf_glbp_hello_vgstate = -1;
static gint hf_glbp_hello_unknown11 = -1;
static gint hf_glbp_hello_priority = -1;
static gint hf_glbp_hello_unknown12 = -1;
static gint hf_glbp_hello_helloint = -1;
static gint hf_glbp_hello_holdint = -1;
static gint hf_glbp_hello_redirect = -1;
static gint hf_glbp_hello_timeout = -1;
static gint hf_glbp_hello_unknown13 = -1;
static gint hf_glbp_hello_addrtype = -1;
static gint hf_glbp_hello_addrlen = -1;
static gint hf_glbp_hello_virtualipv4 = -1;
static gint hf_glbp_hello_virtualipv6 = -1;
static gint hf_glbp_hello_virtualunk = -1;
/* glbp type = 2 - Request/Response??? */
static gint hf_glbp_reqresp_forwarder = -1;
static gint hf_glbp_reqresp_vfstate = -1;
static gint hf_glbp_reqresp_unknown21 = -1;
static gint hf_glbp_reqresp_priority = -1;
static gint hf_glbp_reqresp_weight = -1;
static gint hf_glbp_reqresp_unknown22 = -1;
static gint hf_glbp_reqresp_virtualmac = -1;
/* glbp type = 3 - Auth */
static gint hf_glbp_auth_authtype = -1;
static gint hf_glbp_auth_authlength = -1;
static gint hf_glbp_auth_plainpass = -1;
static gint hf_glbp_auth_md5hash = -1;
static gint hf_glbp_auth_md5chainindex = -1;
static gint hf_glbp_auth_md5chainhash = -1;
static gint hf_glbp_auth_authunknown = -1;
/* unknown type */
static gint hf_glbp_unknown_data = -1;
static gint ett_glbp = -1;
static gint ett_glbp_tlv = -1;
/* filterable expert infos */
static expert_field ei_glbp_ipv4_wrong_length = EI_INIT;
static expert_field ei_glbp_ipv6_wrong_length = EI_INIT;
static expert_field ei_glbp_tlv_length_too_small = EI_INIT;
static expert_field ei_glbp_tlv_invalid_bytes_used = EI_INIT;
static const value_string glbp_type_vals[] = {
{ 1, "Hello" },
{ 2, "Request/Response?" },
{ 3, "Auth" },
{ 0, NULL }
};
#if 0
static const value_string glbp_reqresp_forwarder_vals[] = {
{ 0, "Request?" },
{ 2, "Response?" },
{ 0, NULL }
};
#endif
static const value_string glbp_addr_type_vals[] = {
{ 1, "IPv4" },
{ 2, "IPv6" },
{ 0, NULL }
};
static const value_string glbp_auth_type_vals[] = {
{ 0, "None" },
{ 1, "Plain text" },
{ 2, "MD5 string" },
{ 3, "MD5 chain" },
{ 0, NULL }
};
#if 0
static const value_string glbp_loadbalancing_vals[] = {
{ x, "None (AVG only)" },
{ x, "Weighted" },
{ x, "Host dependent" },
{ x, "Round robin" },
{ 0, NULL }
};
#endif
static const value_string glbp_vgstate_vals[] = {
#if 0
{ x, "Disabled" },
{ x, "Initial" },
#endif
{ 4, "Listen" },
{ 8, "Speak" },
{ 0x10, "Standby" },
{ 0x20, "Active" },
{ 0, NULL }
};
static const value_string glbp_vfstate_vals[] = {
#if 0
{ x, "Disabled" },
{ x, "Initial" },
#endif
{ 4, "Listen" },
{ 0x20, "Active" },
{ 0, NULL }
};
static int
dissect_glbp_hello(tvbuff_t *tvb, int offset,
packet_info *pinfo, proto_tree *tlv_tree)
{
guint8 addrtype;
guint8 addrlen;
proto_tree_add_item(tlv_tree, hf_glbp_hello_unknown10, tvb, offset, 1, ENC_NA);
offset ++;
proto_tree_add_item(tlv_tree, hf_glbp_hello_vgstate, tvb, offset, 1, ENC_BIG_ENDIAN);
offset ++;
proto_tree_add_item(tlv_tree, hf_glbp_hello_unknown11, tvb, offset, 1, ENC_NA);
offset ++;
proto_tree_add_item(tlv_tree, hf_glbp_hello_priority, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_hello_unknown12, tvb, offset, 2, ENC_NA);
offset += 2;
proto_tree_add_item(tlv_tree, hf_glbp_hello_helloint, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(tlv_tree, hf_glbp_hello_holdint, tvb, offset, 4, ENC_BIG_ENDIAN);
offset += 4;
proto_tree_add_item(tlv_tree, hf_glbp_hello_redirect, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(tlv_tree, hf_glbp_hello_timeout, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(tlv_tree, hf_glbp_hello_unknown13, tvb, offset, 2, ENC_NA);
offset += 2;
proto_tree_add_item(tlv_tree, hf_glbp_hello_addrtype, tvb, offset, 1, ENC_BIG_ENDIAN);
addrtype = tvb_get_guint8( tvb, offset);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_hello_addrlen, tvb, offset, 1, ENC_BIG_ENDIAN);
addrlen = tvb_get_guint8(tvb, offset);
offset++;
switch (addrtype) {
case 1:
if (addrlen != 4) {
expert_add_info_format(pinfo, NULL, &ei_glbp_ipv4_wrong_length,
"Wrong IPv4 address length: %u", addrlen);
return offset + addrlen;
}
proto_tree_add_item(tlv_tree, hf_glbp_hello_virtualipv4, tvb, offset, addrlen, ENC_BIG_ENDIAN);
break;
case 2:
if (addrlen != 16) {
expert_add_info_format(pinfo, NULL, &ei_glbp_ipv6_wrong_length,
"Wrong IPv6 address length: %u", addrlen);
return offset + addrlen;
}
proto_tree_add_item(tlv_tree, hf_glbp_hello_virtualipv6, tvb, offset, addrlen, ENC_NA);
break;
default:
proto_tree_add_item(tlv_tree, hf_glbp_hello_virtualunk, tvb, offset, addrlen, ENC_NA);
break;
}
offset += addrlen;
col_append_fstr(pinfo->cinfo, COL_INFO, ", %s",
val_to_str(addrtype, glbp_addr_type_vals, "%d"));
return offset;
}
static int
dissect_glbp_reqresp(tvbuff_t *tvb, int offset,
packet_info *pinfo _U_, proto_tree *tlv_tree)
{
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_forwarder, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_vfstate, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_unknown21, tvb, offset, 1, ENC_NA);
offset += 1;
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_priority, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_weight, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_unknown22, tvb, offset, 7, ENC_NA);
offset += 7;
proto_tree_add_item(tlv_tree, hf_glbp_reqresp_virtualmac, tvb, offset, 6, ENC_NA);
offset += 6;
return offset;
}
static int
dissect_glbp_auth(tvbuff_t *tvb, int offset,
packet_info *pinfo _U_, proto_tree *tlv_tree)
{
guint8 authtype;
guint8 authlength;
proto_tree_add_item(tlv_tree, hf_glbp_auth_authtype, tvb, offset, 1, ENC_BIG_ENDIAN);
authtype = tvb_get_guint8(tvb, offset);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_auth_authlength, tvb, offset, 1, ENC_BIG_ENDIAN);
authlength = tvb_get_guint8(tvb, offset);
offset++;
switch(authtype) {
case 1:
proto_tree_add_item(tlv_tree, hf_glbp_auth_plainpass, tvb, offset, authlength, ENC_ASCII|ENC_NA);
offset += authlength;
break;
case 2:
proto_tree_add_item(tlv_tree, hf_glbp_auth_md5hash, tvb, offset, authlength, ENC_NA);
offset += authlength;
break;
case 3:
proto_tree_add_item(tlv_tree, hf_glbp_auth_md5chainindex, tvb, offset, 4, ENC_BIG_ENDIAN);
proto_tree_add_item(tlv_tree, hf_glbp_auth_md5chainhash, tvb, offset+4, authlength-4, ENC_NA);
offset += authlength;
break;
default:
proto_tree_add_item(tlv_tree, hf_glbp_auth_authunknown, tvb, offset, authlength, ENC_NA);
offset += authlength;
break;
}
return offset;
}
static int
dissect_glbp_unknown(tvbuff_t *tvb, int offset, guint32 length,
packet_info *pinfo _U_, proto_tree *tlv_tree)
{
proto_tree_add_item(tlv_tree, hf_glbp_unknown_data, tvb, offset, length, ENC_NA);
offset += length;
return offset;
}
static int
dissect_glbp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *glbp_tree;
proto_tree *tlv_tree;
proto_item *ti;
guint8 type;
int offset = 0;
int lastoffset;
guint8 length;
guint16 group;
group = tvb_get_ntohs(tvb, 2);
col_set_str(pinfo->cinfo, COL_PROTOCOL, "GLBP");
col_add_fstr(pinfo->cinfo, COL_INFO, "G: %d", group);
ti = proto_tree_add_item(tree, proto_glbp, tvb, 0, -1, ENC_NA);
glbp_tree = proto_item_add_subtree(ti, ett_glbp);
/* glbp header? */
proto_tree_add_item(glbp_tree, hf_glbp_version, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(glbp_tree, hf_glbp_unknown1, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(glbp_tree, hf_glbp_group, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
proto_tree_add_item(glbp_tree, hf_glbp_unknown2, tvb, offset, 2, ENC_NA);
offset += 2;
proto_tree_add_item(glbp_tree, hf_glbp_ownerid, tvb, offset, 6, ENC_NA);
offset += 6;
while (tvb_reported_length_remaining(tvb, offset) > 0) {
type = tvb_get_guint8(tvb, offset);
length = tvb_get_guint8(tvb, offset+1);
if (length < 2) {
expert_add_info_format(pinfo, NULL, &ei_glbp_tlv_length_too_small,
"Length %u too small", length);
return offset;
}
length -= 2;
ti = proto_tree_add_item(glbp_tree, hf_glbp_tlv, tvb, offset, length+2, ENC_BIG_ENDIAN);
tlv_tree = proto_item_add_subtree(ti, ett_glbp_tlv);
proto_item_append_text(ti, " l=%d, t=%s", length+2,
val_to_str(type, glbp_type_vals, "%d"));
proto_tree_add_item(tlv_tree, hf_glbp_type, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
proto_tree_add_item(tlv_tree, hf_glbp_length, tvb, offset, 1, ENC_BIG_ENDIAN);
offset++;
col_append_fstr(pinfo->cinfo, COL_INFO, ", %s",
val_to_str(type, glbp_type_vals, "%d"));
lastoffset = offset;
switch(type) {
case 1: /* Hello */
offset = dissect_glbp_hello(tvb, offset, pinfo, tlv_tree);
break;
case 2: /* Request/Response */
offset = dissect_glbp_reqresp(tvb, offset, pinfo, tlv_tree);
break;
case 3: /* Plaintext auth */
offset = dissect_glbp_auth(tvb, offset, pinfo, tlv_tree);
break;
default:
offset = dissect_glbp_unknown(tvb, offset, length, pinfo, tlv_tree);
break;
}
if (lastoffset >= offset) {
expert_add_info(pinfo, NULL, &ei_glbp_tlv_invalid_bytes_used);
return lastoffset;
}
/* Skip over trailing bytes before starting with the next element */
if (lastoffset + length > offset)
offset = lastoffset + length;
}
return offset;
}
static gboolean
test_glbp(tvbuff_t *tvb, packet_info *pinfo)
{
guint32 unknown1;
if ( tvb_captured_length(tvb) < 2)
return FALSE;
unknown1 = tvb_get_guint8(tvb, 1);
if (tvb_get_guint8(tvb, 0) != 1 /* version? */
|| unknown1 > 4
|| pinfo->srcport != pinfo->destport
#if 0 /* XXX */
|| unknown1 == 0 && pinfo->net_dst != ipv4:224.0.0.102
&& pinfo->net_dst != ipv6:...
|| unknown1 == 0 && pinfo->dl_src != ether:c2-00-7c-b8-00-00
#endif
) {
return FALSE;
}
return TRUE;
}
static int
dissect_glbp_static(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
if ( !test_glbp(tvb, pinfo) ) {
return 0;
}
return dissect_glbp(tvb, pinfo, tree);
}
void
proto_register_glbp(void)
{
static hf_register_info hf[] = {
/* Header */
{ &hf_glbp_version,
{ "Version?", "glbp.version", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_unknown1,
{ "Unknown1", "glbp.unknown1", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_group,
{ "Group", "glbp.group", FT_UINT16, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_unknown2,
{ "Unknown2", "glbp.unknown2", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_ownerid,
{ "Owner ID", "glbp.ownerid", FT_ETHER, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_tlv,
{ "TLV", "glbp.tlv", FT_PROTOCOL, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_type,
{ "Type", "glbp.type", FT_UINT8, BASE_DEC, VALS(glbp_type_vals),
0x0, NULL, HFILL }},
{ &hf_glbp_length,
{ "Length", "glbp.length", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
/* type = 1 - hello */
{ &hf_glbp_hello_unknown10,
{ "Unknown1-0", "glbp.hello.unknown10", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_vgstate,
{ "VG state?", "glbp.hello.vgstate", FT_UINT8, BASE_DEC, VALS(glbp_vgstate_vals),
0x0, NULL, HFILL }},
{ &hf_glbp_hello_unknown11,
{ "Unknown1-1", "glbp.hello.unknown11", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_priority,
{ "Priority", "glbp.hello.priority", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_unknown12,
{ "Unknown1-2", "glbp.hello.unknown12", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_helloint,
{ "Helloint", "glbp.hello.helloint", FT_UINT32, BASE_DEC, NULL,
0x0, "Hello interval [msec]", HFILL }},
{ &hf_glbp_hello_holdint,
{ "Holdint", "glbp.hello.holdint", FT_UINT32, BASE_DEC, NULL,
0x0, "Hold interval [msec]", HFILL }},
{ &hf_glbp_hello_redirect,
{ "Redirect", "glbp.hello.redirect", FT_UINT16, BASE_DEC, NULL,
0x0, "Redirect interval [sec]", HFILL }},
{ &hf_glbp_hello_timeout,
{ "Timeout", "glbp.hello.timeout", FT_UINT16, BASE_DEC, NULL,
0x0, "Forwarder timeout interval [sec]", HFILL }},
{ &hf_glbp_hello_unknown13,
{ "Unknown1-3", "glbp.hello.unknown13", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_addrtype,
{ "Address type", "glbp.hello.addrtype", FT_UINT8, BASE_DEC, VALS(glbp_addr_type_vals),
0x0, NULL, HFILL }},
{ &hf_glbp_hello_addrlen,
{ "Address length", "glbp.hello.addrlen", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_virtualipv4,
{ "Virtual IPv4", "glbp.hello.virtualipv4", FT_IPv4, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_virtualipv6,
{ "Virtual IPv6", "glbp.hello.virtualipv6", FT_IPv6, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_hello_virtualunk,
{ "Virtual Unknown", "glbp.hello.virtualunk", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
/* type = 2 - request/response??? */
{ &hf_glbp_reqresp_forwarder,
{ "Forwarder?", "glbp.reqresp.forwarder", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_reqresp_vfstate,
{ "VF state?", "glbp.reqresp.vfstate", FT_UINT8, BASE_DEC, VALS(glbp_vfstate_vals),
0x0, NULL, HFILL }},
{ &hf_glbp_reqresp_unknown21,
{ "Unknown2-1", "glbp.reqresp.unknown21", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_reqresp_priority,
{ "Priority", "glbp.reqresp.priority", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_reqresp_weight,
{ "Weight", "glbp.reqresp.weight", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_reqresp_unknown22,
{ "Unknown2-2", "glbp.reqresp.unknown22", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_reqresp_virtualmac,
{ "Virtualmac", "glbp.reqresp.virtualmac", FT_ETHER, BASE_NONE, NULL,
0x0, NULL, HFILL }},
/* type = 3 - auth */
{ &hf_glbp_auth_authtype,
{ "Authtype", "glbp.auth.authtype", FT_UINT8, BASE_DEC, VALS(glbp_auth_type_vals),
0x0, NULL, HFILL }},
{ &hf_glbp_auth_authlength,
{ "Authlength", "glbp.auth.authlength", FT_UINT8, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_auth_plainpass,
{ "Plain pass", "glbp.auth.plainpass", FT_STRING, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_auth_md5hash,
{ "MD5-string hash", "glbp.auth.md5hash", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_auth_md5chainindex,
{ "MD5-chain index", "glbp.auth.md5chainindex", FT_UINT32, BASE_DEC, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_auth_md5chainhash,
{ "MD5-chain hash", "glbp.auth.md5chainhash", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
{ &hf_glbp_auth_authunknown,
{ "Unknown auth value", "glbp.auth.authunknown", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
/* type = unknown */
{ &hf_glbp_unknown_data,
{ "Unknown TLV data", "glbp.unknown.data", FT_BYTES, BASE_NONE, NULL,
0x0, NULL, HFILL }},
};
static gint *ett[] = {
&ett_glbp,
&ett_glbp_tlv,
};
static ei_register_info ei[] = {
{ &ei_glbp_ipv4_wrong_length,
{ "glbp.ipv4_wrong_length", PI_MALFORMED, PI_ERROR,
"Wrong IPv4 address length: %u",
EXPFILL }},
{ &ei_glbp_ipv6_wrong_length,
{ "glbp.ipv6_wrong_length", PI_MALFORMED, PI_ERROR,
"Wrong IPv6 address length: %u",
EXPFILL }},
{ &ei_glbp_tlv_length_too_small,
{ "glbp.tlv_length_too_small", PI_MALFORMED, PI_ERROR,
"Length %u too small",
EXPFILL }},
{ &ei_glbp_tlv_invalid_bytes_used,
{ "glbp.tlv_invalid_bytes_used", PI_MALFORMED, PI_ERROR,
"Zero or negative length",
EXPFILL }},
};
expert_module_t* expert_glbp;
proto_glbp = proto_register_protocol("Gateway Load Balancing Protocol", "GLBP", "glbp");
proto_register_field_array(proto_glbp, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
expert_glbp = expert_register_protocol(proto_glbp);
expert_register_field_array(expert_glbp, ei, array_length(ei));
}
void
proto_reg_handoff_glbp(void)
{
dissector_handle_t glbp_handle;
glbp_handle = create_dissector_handle(dissect_glbp_static, proto_glbp);
dissector_add_uint_with_preference("udp.port", GLBP_UDP_PORT, glbp_handle);
}
/*
* 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:
*/