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|
/* packet-netlink.c
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/* http://www.tcpdump.org/linktypes/LINKTYPE_NETLINK.html */
#define NEW_PROTO_TREE_API
#include "config.h"
#include <glib.h>
#include <epan/arptypes.h>
#include <epan/packet.h>
#include <wiretap/wtap.h>
#include "packet-netlink.h"
void proto_register_netlink(void);
void proto_reg_handoff_netlink(void);
/*
* A DLT_LINUX_SLL fake link-layer header.
*/
#define SLL_HEADER_SIZE 16 /* total header length */
static const value_string netlink_family_vals[] = {
{ WS_NETLINK_ROUTE, "Route" },
{ WS_NETLINK_UNUSED, "Unused" },
{ WS_NETLINK_USERSOCK, "user-mode" },
{ WS_NETLINK_FIREWALL, "Unused (formerly: ip_queue)" },
{ WS_NETLINK_SOCK_DIAG, "socket monitoring" },
{ WS_NETLINK_NFLOG, "Netfilter ULOG" },
{ WS_NETLINK_XFRM, "IPsec" },
{ WS_NETLINK_SELINUX, "SELinux events" },
{ WS_NETLINK_ISCSI, "Open-iSCSI" },
{ WS_NETLINK_AUDIT, "Auditing" },
{ WS_NETLINK_FIB_LOOKUP, "FIB lookup" },
{ WS_NETLINK_CONNECTOR, "Kernel connector" },
{ WS_NETLINK_NETFILTER, "Netfilter" },
{ WS_NETLINK_IP6_FW, "Unused (formerly: ip6_queue)" },
{ WS_NETLINK_DNRTMSG, "DECnet routing messages" },
{ WS_NETLINK_KOBJECT_UEVENT, "Kernel messages" },
{ WS_NETLINK_GENERIC, "Generic" },
{ WS_NETLINK_SCSITRANSPORT, "SCSI Transports" },
{ WS_NETLINK_ECRYPTFS, "ecryptfs" },
{ WS_NETLINK_RDMA, "RDMA" },
{ WS_NETLINK_CRYPTO, "Crypto layer" },
{ 0, NULL }
};
value_string_ext netlink_family_vals_ext = VALUE_STRING_EXT_INIT(netlink_family_vals);
static const value_string type_vals[] = {
{ WS_NLMSG_NOOP, "nothing" },
{ WS_NLMSG_ERROR, "error" },
{ WS_NLMSG_DONE, "end of a dump" },
{ WS_NLMSG_OVERRUN, "data lost" },
{ 0, NULL }
};
static dissector_handle_t netlink_handle;
static header_field_info *hfi_netlink = NULL;
#define NETLINK_HFI_INIT HFI_INIT(proto_netlink)
static header_field_info hfi_netlink_hatype NETLINK_HFI_INIT =
{ "Link-layer address type", "netlink.hatype", FT_UINT16, BASE_DEC,
NULL, 0x0, NULL, HFILL };
/* Linux netlink protocol type */
static header_field_info hfi_netlink_family NETLINK_HFI_INIT =
{ "Family", "netlink.family", FT_UINT16, BASE_HEX | BASE_EXT_STRING,
&netlink_family_vals_ext, 0x00, NULL, HFILL };
static header_field_info hfi_netlink_hdr_len NETLINK_HFI_INIT =
{ "Length", "netlink.hdr_len", FT_UINT32, BASE_DEC,
NULL, 0x00, NULL, HFILL };
static header_field_info hfi_netlink_hdr_type NETLINK_HFI_INIT =
{ "Type", "netlink.hdr_type", FT_UINT16, BASE_HEX,
VALS(type_vals), 0x00, NULL, HFILL };
static header_field_info hfi_netlink_hdr_flags NETLINK_HFI_INIT =
{ "Flags", "netlink.hdr_flags", FT_UINT16, BASE_HEX,
NULL, 0x00, NULL, HFILL };
static header_field_info hfi_netlink_hdr_seq NETLINK_HFI_INIT =
{ "Sequence", "netlink.hdr_seq", FT_UINT32, BASE_HEX,
NULL, 0x00, NULL, HFILL };
static header_field_info hfi_netlink_hdr_pid NETLINK_HFI_INIT =
{ "Port ID", "netlink.hdr_pid", FT_UINT32, BASE_HEX,
NULL, 0x00, NULL, HFILL };
static header_field_info hfi_netlink_len NETLINK_HFI_INIT =
{ "Len", "netlink.len", FT_UINT16, BASE_DEC,
NULL, 0x00, NULL, HFILL };
static gint ett_netlink_cooked = -1;
static gint ett_netlink_msghdr = -1;
static gint ett_netlink_msg = -1;
static dissector_table_t netlink_dissector_table;
static dissector_handle_t data_handle;
int
dissect_netlink_attributes(tvbuff_t *tvb, header_field_info *hfi_type, int ett, void *data, proto_tree *tree, int offset, netlink_attributes_cb_t cb)
{
/* align to 4 */
offset = (offset + 3) & ~3;
while (tvb_length_remaining(tvb, offset) >= 4) {
guint16 rta_len, rta_type;
int end_offset;
proto_item *ti;
proto_tree *attr_tree;
rta_len = tvb_get_letohs(tvb, offset);
if (rta_len < 4) {
/* XXX invalid expert */
break;
}
end_offset = (offset + rta_len + 3) & ~3;
attr_tree = proto_tree_add_subtree(tree, tvb, offset, end_offset - offset, ett, &ti, "Attribute");
proto_tree_add_item(attr_tree, &hfi_netlink_len, tvb, offset, 2, ENC_LITTLE_ENDIAN);
offset += 2;
rta_type = tvb_get_letohs(tvb, offset);
proto_tree_add_item(attr_tree, hfi_type, tvb, offset, 2, ENC_LITTLE_ENDIAN);
offset += 2;
if (hfi_type->strings) {
/* XXX, export hf_try_val_to_str */
const char *rta_str = try_val_to_str(rta_type, (const value_string *) hfi_type->strings);
if (rta_str)
proto_item_append_text(ti, ": %s", rta_str);
}
if (!cb(tvb, data, attr_tree, rta_type, offset, rta_len - 4)) {
/* not handled */
}
if (end_offset <= offset)
break;
offset = end_offset;
}
return offset;
}
static int
dissect_netlink(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *_data _U_)
{
guint16 protocol, hatype;
proto_item *ti;
tvbuff_t *next_tvb;
proto_tree *fh_tree = NULL;
int offset;
hatype = tvb_get_ntohs(tvb, 2);
if (hatype != ARPHRD_NETLINK)
return 0;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "Netlink");
col_clear(pinfo->cinfo, COL_INFO);
if (tree) {
ti = proto_tree_add_protocol_format(tree, hfi_netlink->id, tvb, 0,
SLL_HEADER_SIZE, "Linux netlink (cooked header)");
fh_tree = proto_item_add_subtree(ti, ett_netlink_cooked);
}
/* Unused 2B */
offset = 2;
proto_tree_add_item(fh_tree, &hfi_netlink_hatype, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
/* Unused 10B */
offset += 10;
protocol = tvb_get_ntohs(tvb, offset);
proto_tree_add_item(fh_tree, &hfi_netlink_family, tvb, offset, 2, ENC_BIG_ENDIAN);
offset += 2;
/* DISSECTOR_ASSERT(offset == 16); */
while (tvb_reported_length_remaining(tvb, offset) >= 16) {
struct packet_netlink_data data;
int pkt_end_offset;
guint32 pkt_len;
guint32 port_id;
proto_tree *fh_msg;
proto_tree *fh_hdr;
int encoding = ENC_LITTLE_ENDIAN; /* XXX */
pkt_len = tvb_get_letohl(tvb, offset);
pkt_end_offset = offset + pkt_len;
fh_msg = proto_tree_add_subtree(tree, tvb, offset, pkt_len, ett_netlink_msg, NULL, "Netlink message");
fh_hdr = proto_tree_add_subtree(fh_msg, tvb, offset, 16, ett_netlink_msghdr, NULL, "Header");
proto_tree_add_item(fh_hdr, &hfi_netlink_hdr_len, tvb, offset, 4, encoding);
offset += 4;
proto_tree_add_item(fh_hdr, &hfi_netlink_hdr_type, tvb, offset, 2, encoding);
data.type = tvb_get_letohs(tvb, offset);
offset += 2;
proto_tree_add_item(fh_hdr, &hfi_netlink_hdr_flags, tvb, offset, 2, encoding);
offset += 2;
proto_tree_add_item(fh_hdr, &hfi_netlink_hdr_seq, tvb, offset, 4, encoding);
offset += 4;
proto_tree_add_item(fh_hdr, &hfi_netlink_hdr_pid, tvb, offset, 4, encoding);
port_id = tvb_get_letohl(tvb, offset);
offset += 4;
/* XXX */
if (port_id == 0x00)
pinfo->p2p_dir = P2P_DIR_SENT; /* userspace -> kernel */
else
pinfo->p2p_dir = P2P_DIR_RECV; /* userspace or kernel -> userspace */
if (pkt_len > 16) {
data.magic = PACKET_NETLINK_MAGIC;
data.encoding = encoding;
next_tvb = tvb_new_subset_length(tvb, offset, pkt_len-16);
if (!dissector_try_uint_new(netlink_dissector_table, protocol, next_tvb, pinfo, fh_msg, TRUE, &data))
call_dissector(data_handle, next_tvb, pinfo, fh_msg);
} else if (pkt_len != 16) {
/* XXX, expert info */
break;
}
offset = pkt_end_offset;
}
return offset;
}
void
proto_register_netlink(void)
{
#ifndef HAVE_HFI_SECTION_INIT
static header_field_info *hfi[] = {
/* Cooked header */
&hfi_netlink_hatype,
&hfi_netlink_family,
/* Netlink message header */
&hfi_netlink_hdr_len,
&hfi_netlink_hdr_type,
&hfi_netlink_hdr_flags,
&hfi_netlink_hdr_seq,
&hfi_netlink_hdr_pid,
};
#endif
static gint *ett[] = {
&ett_netlink_cooked,
&ett_netlink_msghdr,
&ett_netlink_msg
};
int proto_netlink;
proto_netlink = proto_register_protocol("Linux netlink protocol", "NETLINK", "netlink" );
hfi_netlink = proto_registrar_get_nth(proto_netlink);
proto_register_fields(proto_netlink, hfi, array_length(hfi));
proto_register_subtree_array(ett, array_length(ett));
netlink_handle = new_create_dissector_handle(dissect_netlink, proto_netlink);
netlink_dissector_table = register_dissector_table(
"netlink.protocol",
"Linux netlink protocol type",
FT_UINT16,
BASE_HEX
);
}
void
proto_reg_handoff_netlink(void)
{
data_handle = find_dissector("data");
dissector_add_uint("wtap_encap", WTAP_ENCAP_NETLINK, netlink_handle);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/
|
