/* packet-rmi.c
 * Routines for java rmiregistry dissection
 * Copyright 2002, Michael Stiller <ms@2scale.net>
 *
 * 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 "packet-rmi.h"

void proto_register_rmi(void);
void proto_reg_handoff_rmi(void);

static dissector_handle_t rmi_handle;

static void
dissect_ser(tvbuff_t *tvb, proto_tree *tree);

static rmi_type
get_rmi_type(tvbuff_t *tvb, gint offset, int datalen);

/* Initialize the protocol and registered fields */
static int proto_rmi;
static int proto_ser;
static int hf_rmi_magic;
static int hf_rmi_version;
static int hf_rmi_protocol;
static int hf_rmi_inputmessage;
static int hf_rmi_outputmessage;
static int hf_rmi_epid_length;
static int hf_rmi_epid_hostname;
static int hf_rmi_epid_port;
static int hf_rmi_serialization_data;
static int hf_rmi_unique_identifier;

static int hf_ser_magic;
static int hf_ser_version;

/* Initialize the subtree pointers */
static gint ett_rmi;
static gint ett_rmi_magic;
static gint ett_rmi_version;
static gint ett_rmi_inputmessage;
static gint ett_rmi_outputmessage;
static gint ett_rmi_epid_length;
static gint ett_rmi_epid_hostname;
static gint ett_rmi_epid_port;
static gint ett_rmi_endpoint_identifier;

static gint ett_ser;

/*
 * See
 *
 *     http://java.sun.com/products/jdk/1.2/docs/guide/rmi/spec/rmi-protocol.doc1.html
 *
 * for RMI, and
 *
 *     http://java.sun.com/products/jdk/1.2/docs/guide/serialization/spec/protocol.doc.html
 *
 * for the serialization protocol.
 */

#define TCP_PORT_RMI   1099

static const value_string rmi_protocol_str[] = {
    {RMI_OUTPUTSTREAM_PROTOCOL_STREAM,    "StreamProtocol"},
    {RMI_OUTPUTSTREAM_PROTOCOL_SINGLEOP,  "SingleOpProtocol"},
    {RMI_OUTPUTSTREAM_PROTOCOL_MULTIPLEX, "MultiPlexProtocol"},
    {0, NULL}
};

static const value_string rmi_output_message_str[] = {
    {RMI_OUTPUTSTREAM_MESSAGE_CALL,       "Call"},
    {RMI_OUTPUTSTREAM_MESSAGE_PING,       "Ping"},
    {RMI_OUTPUTSTREAM_MESSAGE_DGCACK,     "DgcAck"},
    {0, NULL}
};

static const value_string rmi_input_message_str[] = {
    {RMI_INPUTSTREAM_MESSAGE_ACK,          "ProtocolAck"},
    {RMI_INPUTSTREAM_MESSAGE_NOTSUPPORTED, "ProtocolNotSupported"},
    {RMI_INPUTSTREAM_MESSAGE_RETURNDATA,   "ReturnData"},
    {RMI_INPUTSTREAM_MESSAGE_PINGACK,      "PingAck"},
    {0, NULL}
};

static int
dissect_rmi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
    proto_item *ti;
    proto_tree *rmi_tree;

    tvbuff_t   *next_tvb;

    gint        offset = 0;
    gint        next_offset;
    int         datalen;

    guint16     version, len, port;
    guint8      message, proto;

    rmi_type    rmitype;

/* Make entries in Protocol column and Info column on summary display */
    col_set_str(pinfo->cinfo, COL_PROTOCOL, "RMI");

    datalen = tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE);

    rmitype = get_rmi_type(tvb, offset, datalen);

    switch(rmitype) {
    case RMI_OUTPUTSTREAM:
        version = tvb_get_ntohs(tvb,4);
        col_add_fstr(pinfo->cinfo, COL_INFO,
                     "JRMI, Version: %d, ", version);

        proto   = tvb_get_guint8(tvb, 6);
        col_append_str(pinfo->cinfo, COL_INFO,
                       val_to_str_const(proto, rmi_protocol_str,
                                        "Unknown protocol"));
        break;
    case RMI_OUTPUTMESSAGE:
        message = tvb_get_guint8(tvb,0);
        col_set_str(pinfo->cinfo, COL_INFO,
                    "JRMI, ");
        col_append_str(pinfo->cinfo, COL_INFO,
                       val_to_str_const(message, rmi_output_message_str,
                                        "Unknown message"));
        break;
    case RMI_INPUTSTREAM:
        message = tvb_get_guint8(tvb,0);
        col_set_str(pinfo->cinfo, COL_INFO,
                    "JRMI, ");
        col_append_str(pinfo->cinfo, COL_INFO,
                       val_to_str_const(message, rmi_input_message_str,
                                        "Unknown message"));
        break;
    case SERIALIZATION_DATA:
        version = tvb_get_ntohs(tvb,2);
        col_add_fstr(pinfo->cinfo, COL_INFO,
                     "Serialization data, Version: %d", version);
        break;
    default:
        col_set_str(pinfo->cinfo, COL_INFO, "Continuation");
        break;
    }

    if (tree) {
        ti = proto_tree_add_item(tree, proto_rmi, tvb, 0, -1, ENC_NA);
        rmi_tree = proto_item_add_subtree(ti, ett_rmi);
        switch(rmitype) {
        case RMI_OUTPUTSTREAM:
            /* XXX - uint, or string? */
            proto_tree_add_item(rmi_tree, hf_rmi_magic,
                                tvb, offset,     4, ENC_BIG_ENDIAN);
            proto_tree_add_item(rmi_tree, hf_rmi_version,
                                tvb, offset + 4, 2, ENC_BIG_ENDIAN);
            proto_tree_add_item(rmi_tree, hf_rmi_protocol,
                                tvb, offset + 6, 1, ENC_BIG_ENDIAN);
            break;
        case RMI_INPUTSTREAM:
            message = tvb_get_guint8(tvb, 0);
            proto_tree_add_uint(rmi_tree, hf_rmi_inputmessage,
                                tvb, offset, 1, message);
            if(message == RMI_INPUTSTREAM_MESSAGE_ACK) {
                proto_tree* endpoint_tree = proto_tree_add_subtree(rmi_tree, tvb, offset + 1, -1,
                                    ett_rmi_endpoint_identifier, NULL, "EndPointIdentifier");
                /* MESSAGE_ACK should include EndpointIdentifier */
                len = tvb_get_ntohs(tvb, 1);
                proto_tree_add_uint(endpoint_tree, hf_rmi_epid_length,
                                    tvb, offset + 1, 2, len);
                if (len > 0) {
                    proto_tree_add_item(endpoint_tree, hf_rmi_epid_hostname,
                                      tvb, offset + 3, len, ENC_ASCII);
                } else {
                    proto_tree_add_string(endpoint_tree, hf_rmi_epid_hostname,
                                      tvb, offset + 3, len, "[Empty]");
                }

                port = tvb_get_ntohs(tvb, offset + len + 5);
                proto_tree_add_uint(endpoint_tree, hf_rmi_epid_port,
                                    tvb, offset + len + 5, 2, port);
            }
            if(message == RMI_INPUTSTREAM_MESSAGE_RETURNDATA) {
                proto_tree_add_bytes_format(rmi_tree, hf_rmi_serialization_data, tvb, offset + 1, -1,
                                    NULL, "Serialization Data");
                next_tvb = tvb_new_subset_remaining(tvb, offset + 1);
                dissect_ser(next_tvb, tree);
            }
            break;
        case RMI_OUTPUTMESSAGE:
            message = tvb_get_guint8(tvb, 0);
            proto_tree_add_uint(rmi_tree, hf_rmi_outputmessage,
                                tvb, offset, 1, message);
            if(message == RMI_OUTPUTSTREAM_MESSAGE_CALL) {
                proto_tree_add_bytes_format(rmi_tree, hf_rmi_serialization_data, tvb, offset + 1, -1,
                                    NULL, "Serialization Data");
                /* XXX */
                next_tvb = tvb_new_subset_remaining(tvb, offset + 1);
                dissect_ser(next_tvb, tree);
            }
            if(message == RMI_OUTPUTSTREAM_MESSAGE_DGCACK) {
                proto_tree_add_item(rmi_tree, hf_rmi_unique_identifier, tvb, offset + 1, -1, ENC_NA);
            }
            break;
        case SERIALIZATION_DATA:
            dissect_ser(tvb, tree);
            break;
        default:
            break;
        }
    }
    return tvb_captured_length(tvb);
}

static void
dissect_ser(tvbuff_t *tvb, proto_tree *tree)
{
    proto_item *ti;
    proto_tree *ser_tree;

    gint offset;

    offset = 0;

    if(tree) {
        ti = proto_tree_add_item(tree, proto_ser, tvb, 0, -1, ENC_NA);
        ser_tree = proto_item_add_subtree(ti, ett_ser);
        proto_tree_add_item(ser_tree, hf_ser_magic,
                            tvb, offset,     2, ENC_BIG_ENDIAN);
        proto_tree_add_item(ser_tree, hf_ser_version,
                            tvb, offset + 2, 2, ENC_BIG_ENDIAN);

    }
}

static rmi_type
get_rmi_type(tvbuff_t *tvb, gint offset, int datalen)
{
    guint16 ser_magic;
    guchar  data[4];

    tvb_memcpy(tvb, data, offset, (datalen > 4) ? 4 : datalen);

    if (datalen >= 2) {
        ser_magic = data[0] << 8 | data[1];
        if (ser_magic == SER_STREAM_MAGIC) {
            return SERIALIZATION_DATA;
        }
    }
    if (datalen >= 4) {
        if(strncmp(data, RMI_MAGIC, 4) == 0) {
            return RMI_OUTPUTSTREAM;
        }
    }
    if (datalen >= 1) {
        if (data[0] == RMI_INPUTSTREAM_MESSAGE_ACK ||
            data[0] == RMI_INPUTSTREAM_MESSAGE_NOTSUPPORTED ||
            data[0] == RMI_INPUTSTREAM_MESSAGE_RETURNDATA ||
            data[0] == RMI_INPUTSTREAM_MESSAGE_PINGACK) {
            return RMI_INPUTSTREAM;
        }
    }
    if (datalen >= 1) {
        if (data[0] == RMI_OUTPUTSTREAM_MESSAGE_CALL ||
            data[0] == RMI_OUTPUTSTREAM_MESSAGE_PING ||
            data[0] == RMI_OUTPUTSTREAM_MESSAGE_DGCACK) {
            return RMI_OUTPUTMESSAGE;
        }
    }
    return CONTINUATION;
}

void
proto_register_rmi(void)
{

    static hf_register_info hf[] = {
        { &hf_rmi_magic,
          { "Magic",   "rmi.magic",
            FT_UINT32, BASE_HEX, NULL, 0x0,
            "RMI Header Magic", HFILL }},
        { &hf_rmi_version,
          { "Version", "rmi.version",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "RMI Protocol Version", HFILL }},
        { &hf_rmi_protocol,
          { "Protocol","rmi.protocol",
            FT_UINT8, BASE_HEX, VALS(rmi_protocol_str), 0x0,
            "RMI Protocol Type", HFILL }},
        { &hf_rmi_inputmessage,
          { "Input Stream Message", "rmi.inputstream.message",
            FT_UINT8, BASE_HEX, VALS(rmi_input_message_str), 0x0,
            "RMI Inputstream Message Token", HFILL }},
        { &hf_rmi_outputmessage,
          { "Output Stream Message", "rmi.outputstream.message",
            FT_UINT8, BASE_HEX, VALS(rmi_output_message_str), 0x0,
            "RMI Outputstream Message token", HFILL }},
        { &hf_rmi_epid_length,
          { "Length", "rmi.endpoint_id.length",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "RMI Endpointidentifier Length", HFILL }},
        { &hf_rmi_epid_hostname,
          { "Hostname", "rmi.endpoint_id.hostname",
            FT_STRING, BASE_NONE, NULL, 0x0,
            "RMI Endpointidentifier Hostname", HFILL }},
        { &hf_rmi_epid_port,
          { "Port", "rmi.endpoint_id.port",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "RMI Endpointindentifier Port", HFILL }},
        { &hf_rmi_serialization_data,
          { "Serialization Data", "rmi.serialization_data",
            FT_BYTES, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},
        { &hf_rmi_unique_identifier,
          { "UniqueIdentifier", "rmi.unique_identifier",
            FT_BYTES, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},

        { &hf_ser_magic,
          { "Magic",   "rmi.ser.magic",
            FT_UINT16, BASE_HEX, NULL, 0x0,
            "Java Serialization Magic", HFILL }},
        { &hf_ser_version,
          { "Version", "rmi.ser.version",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Java Serialization Version", HFILL }},
    };

    static gint *ett[] = {
        &ett_rmi,
        &ett_rmi_magic,
        &ett_rmi_version,
        &ett_rmi_inputmessage,
        &ett_rmi_outputmessage,
        &ett_rmi_epid_length,
        &ett_rmi_epid_hostname,
        &ett_rmi_epid_port,
        &ett_ser,
        &ett_rmi_endpoint_identifier,
    };

    proto_rmi = proto_register_protocol("Java RMI", "RMI", "rmi");
    proto_ser = proto_register_protocol_in_name_only("Java Serialization", "Serialization",
                                        "serialization", proto_rmi, FT_PROTOCOL);
    proto_register_field_array(proto_rmi, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));

    rmi_handle = register_dissector("rmi", dissect_rmi, proto_rmi);
}

void
proto_reg_handoff_rmi(void)
{
    dissector_add_uint_with_preference("tcp.port", TCP_PORT_RMI, rmi_handle);
}

/*
 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 4
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * vi: set shiftwidth=4 tabstop=8 expandtab:
 * :indentSize=4:tabSize=8:noTabs=true:
 */