wireshark/epan/dissectors/packet-banana.c

368 lines
12 KiB
C

/* packet-bananna.c
* Routines for the Twisted Banana serialization protocol dissection
* Copyright 2009, Gerald Combs <gerald@wireshark.org>
*
* $Id$
*
* 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.
*/
/*
* Based on "Banana Protocol Specifications"
* http://twistedmatrix.com/projects/core/documentation/specifications/banana.html
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdlib.h>
#include <glib.h>
#include <epan/packet.h>
#include <epan/prefs.h>
#include <epan/expert.h>
/* Initialize the protocol and registered fields */
static int proto_banana = -1;
static int hf_banana_list = -1;
static int hf_banana_int = -1;
static int hf_banana_string = -1;
static int hf_banana_neg_int = -1;
static int hf_banana_float = -1;
static int hf_banana_lg_int = -1;
static int hf_banana_lg_neg_int = -1;
static int hf_banana_pb = -1;
/* Initialize the subtree pointers */
static gint ett_banana = -1;
static gint ett_list = -1;
static dissector_handle_t banana_handle;
#define BE_LIST 0x80
#define BE_INT 0x81
#define BE_STRING 0x82
#define BE_NEG_INT 0x83
#define BE_FLOAT 0x84
#define BE_LG_INT 0x85
#define BE_LG_NEG_INT 0x86
#define BE_PB 0x87
#define is_element(b) (b >= BE_LIST && b <= BE_PB)
static const value_string type_vals[] = {
{ BE_LIST, "List" },
{ BE_INT, "Integer" },
{ BE_STRING, "String" },
{ BE_NEG_INT, "Negative Integer" },
{ BE_FLOAT, "Float" },
{ BE_LG_INT, "Large Integer" },
{ BE_LG_NEG_INT, "Large Negative Integer" },
{ BE_PB, "pb Profile"},
{ 0, NULL }
};
static const value_string pb_vals[] = {
{ 0x01, "None" },
{ 0x02, "class" },
{ 0x03, "dereference" },
{ 0x04, "reference" },
{ 0x05, "dictionary" },
{ 0x06, "function" },
{ 0x07, "instance" },
{ 0x08, "list" },
{ 0x09, "module" },
{ 0x0a, "persistent" },
{ 0x0b, "tuple" },
{ 0x0c, "unpersistable" },
{ 0x0d, "copy" },
{ 0x0e, "cache" },
{ 0x0f, "cached" },
{ 0x10, "remote" },
{ 0x11, "local" },
{ 0x12, "lcache" },
{ 0x13, "version" },
{ 0x14, "login" },
{ 0x15, "password" },
{ 0x16, "challenge" },
{ 0x17, "logged_in" },
{ 0x18, "not_logged_in" },
{ 0x19, "cachemessage" },
{ 0x1a, "message" },
{ 0x1b, "answer" },
{ 0x1c, "error" },
{ 0x1d, "decref" },
{ 0x1e, "decache" },
{ 0x1f, "uncache" },
{ 0, NULL }
};
#define MAX_ELEMENT_VAL 2147483647 /* Max TE value */
#define MAX_ELEMENT_INT_LEN 4
#define MAX_ELEMENT_VAL_LEN 8
static range_t *global_banana_tcp_range = NULL;
static range_t *banana_tcp_range = NULL;
/* Dissect the packets */
static int
dissect_banana_element(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset) {
proto_item *ti;
proto_tree *list_tree;
guint8 byte = 0;
gint64 val = 0;
gint val_len = 0;
int start_offset = offset;
int old_offset;
int i;
/* Accumulate our value/length 'til we hit a valid type */
while (tvb_length_remaining(tvb, offset) > 0) {
byte = tvb_get_guint8(tvb, offset);
offset++;
if (byte & 0x80) {
if (is_element(byte)) {
break;
} else {
expert_add_info_format(pinfo, NULL, PI_UNDECODED, PI_ERROR, "Unknown type %u", byte);
}
} else {
val_len++;
if (val_len > MAX_ELEMENT_VAL_LEN) {
expert_add_info_format(pinfo, NULL, PI_UNDECODED, PI_ERROR, "Too many value/length bytes");
}
val += byte + (val << 7);
}
}
/* Type */
switch (byte) {
case BE_LIST:
if (val > MAX_ELEMENT_VAL) {
expert_add_info_format(pinfo, NULL, PI_UNDECODED, PI_ERROR, "List length %" G_GINT64_MODIFIER "d longer than we can handle", val);
}
ti = proto_tree_add_uint_format_value(tree, hf_banana_list, tvb, start_offset, offset - start_offset - 1, (guint32) val, "(%d items)", (gint) val);
list_tree = proto_item_add_subtree(ti, ett_list);
for (i = 0; i < val; i++) {
old_offset = offset;
offset += dissect_banana_element(tvb, pinfo, list_tree, offset);
if (offset <= old_offset) {
return offset - start_offset;
}
}
break;
case BE_INT:
if (val > MAX_ELEMENT_VAL) {
expert_add_info_format(pinfo, NULL, PI_MALFORMED, PI_ERROR, "Integer value %" G_GINT64_MODIFIER "d too large", val);
}
proto_tree_add_uint(tree, hf_banana_int, tvb, start_offset, offset - start_offset, (guint32) val);
break;
case BE_STRING:
if (val > MAX_ELEMENT_VAL) {
expert_add_info_format(pinfo, NULL, PI_UNDECODED, PI_ERROR, "String length %" G_GINT64_MODIFIER "d longer than we can handle", val);
}
proto_tree_add_item(tree, hf_banana_string, tvb, offset, (guint32) val, FALSE);
offset += (gint) val;
break;
case BE_NEG_INT:
if (val > MAX_ELEMENT_VAL) {
expert_add_info_format(pinfo, NULL, PI_MALFORMED, PI_ERROR, "Integer value -%" G_GINT64_MODIFIER "d too large", val);
}
proto_tree_add_int(tree, hf_banana_neg_int, tvb, start_offset, offset - start_offset, (gint32) val * -1);
break;
case BE_FLOAT:
proto_tree_add_item(tree, hf_banana_float, tvb, offset, 8, FALSE);
offset += 8;
break;
case BE_LG_INT:
proto_tree_add_item(tree, hf_banana_lg_int, tvb, start_offset, offset - start_offset, FALSE);
break;
case BE_LG_NEG_INT:
proto_tree_add_item(tree, hf_banana_lg_neg_int, tvb, start_offset, offset - start_offset, FALSE);
break;
case BE_PB:
if (val_len > 1) {
expert_add_info_format(pinfo, NULL, PI_MALFORMED, PI_ERROR, "More than 1 byte before pb");
}
/*
* The spec says the pb dictionary value comes after the tag.
* In real-world captures it comes before.
*/
proto_tree_add_item(tree, hf_banana_pb, tvb, offset - 2, 1, FALSE);
break;
default:
return 0;
break;
}
return offset - start_offset;
}
static int
dissect_banana(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
guint8 byte = 0;
gint offset = 0, old_offset;
proto_item *ti;
proto_tree *banana_tree;
/* Check that there's enough data */
if (tvb_length(tvb) < 2)
return 0;
/* Fill in our protocol and info columns */
col_set_str(pinfo->cinfo, COL_PROTOCOL, "Banana");
while (tvb_length_remaining(tvb, offset) > 0 && offset < MAX_ELEMENT_VAL_LEN) {
byte = tvb_get_guint8(tvb, offset);
if (is_element(byte))
break;
offset++;
}
col_add_fstr(pinfo->cinfo, COL_INFO, "First element: %s",
val_to_str(byte, type_vals, "Unknown type: %u"));
if (tree) {
/* Create display subtree for the protocol */
ti = proto_tree_add_item(tree, proto_banana, tvb, 0, -1, FALSE);
banana_tree = proto_item_add_subtree(ti, ett_banana);
offset = 0;
old_offset = -1;
while (offset > old_offset) {
old_offset = offset;
offset += dissect_banana_element(tvb, pinfo, banana_tree, offset);
}
}
/* Return the amount of data this dissector was able to dissect */
return tvb_length(tvb);
}
static void
range_delete_banana_tcp_callback(guint32 port) {
dissector_delete_uint("tcp.port", port, banana_handle);
}
static void
range_add_banana_tcp_callback(guint32 port) {
dissector_add_uint("tcp.port", port, banana_handle);
}
static void
banana_prefs(void) {
range_foreach(banana_tcp_range, range_delete_banana_tcp_callback);
g_free(banana_tcp_range);
banana_tcp_range = range_copy(global_banana_tcp_range);
range_foreach(banana_tcp_range, range_add_banana_tcp_callback);
}
/* Register the protocol with Wireshark */
void
proto_register_banana(void)
{
static hf_register_info hf[] = {
{ &hf_banana_list,
{ "List Length", "banana.list",
FT_UINT32, BASE_DEC, NULL, 0,
"Banana list", HFILL }
},
{ &hf_banana_int,
{ "Integer", "banana.int",
FT_UINT32, BASE_DEC, NULL, 0,
"Banana integer", HFILL }
},
{ &hf_banana_string,
{ "String", "banana.string",
FT_STRING, BASE_NONE, NULL, 0,
"Banana string", HFILL }
},
{ &hf_banana_neg_int,
{ "Negative Integer", "banana.neg_int",
FT_INT32, BASE_DEC, NULL, 0,
"Banana negative integer", HFILL }
},
{ &hf_banana_float,
{ "Float", "banana.float",
FT_DOUBLE, BASE_NONE, NULL, 0,
"Banana float", HFILL }
},
{ &hf_banana_lg_int,
{ "Float", "banana.lg_int",
FT_BYTES, BASE_NONE, NULL, 0,
"Banana large integer", HFILL }
},
{ &hf_banana_lg_neg_int,
{ "Float", "banana.lg_neg_int",
FT_BYTES, BASE_NONE, NULL, 0,
"Banana large negative integer", HFILL }
},
{ &hf_banana_pb,
{ "pb Profile Value", "banana.pb",
FT_UINT8, BASE_HEX, VALS(pb_vals), 0,
"Banana Perspective Broker Profile Value", HFILL }
}
};
module_t *banana_module;
/* Setup protocol subtree array */
static gint *ett[] = {
&ett_banana,
&ett_list
};
/* Register the protocol name and description */
proto_banana = proto_register_protocol("Twisted Banana",
"Banana", "banana");
/* Required function calls to register the header fields and subtrees used */
proto_register_field_array(proto_banana, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
/* Initialize dissector preferences */
banana_module = prefs_register_protocol(proto_banana, banana_prefs);
banana_tcp_range = range_empty();
prefs_register_range_preference(banana_module, "tcp.port", "TCP Ports", "Banana TCP Port range", &global_banana_tcp_range, 65535);
}
void
proto_reg_handoff_banana(void)
{
banana_handle = new_create_dissector_handle(dissect_banana, proto_banana);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* ex: set shiftwidth=4 tabstop=8 expandtab
* :indentSize=4:tabSize=8:noTabs=true:
*/