aboutsummaryrefslogtreecommitdiffstats
path: root/ui/tap_export_pdu.c
blob: 37706ba718d77625d28f654176e910f6c437ca18 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/* tap_export_pdu.c
 * Routines for exporting PDUs to file
 *
 * 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.
 */

#include "config.h"


#include "globals.h"
#include "wiretap/pcap-encap.h"
#include "wsutil/os_version_info.h"
#include "ws_version_info.h"

#include <epan/tap.h>
#include <epan/exported_pdu.h>
#include <epan/epan_dissect.h>
#include <wiretap/wtap.h>
#include <wiretap/wtap_opttypes.h>
#include <wiretap/pcapng.h>

#include "tap_export_pdu.h"

/* Main entry point to the tap */
static gboolean
export_pdu_packet(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const void *data)
{
    const exp_pdu_data_t *exp_pdu_data = (const exp_pdu_data_t *)data;
    exp_pdu_t  *exp_pdu_tap_data = (exp_pdu_t *)tapdata;
    struct wtap_pkthdr pkthdr;
    int err;
    gchar *err_info;
    int buffer_len;
    guint8 *packet_buf;

    memset(&pkthdr, 0, sizeof(struct wtap_pkthdr));
    buffer_len = exp_pdu_data->tvb_captured_length + exp_pdu_data->tlv_buffer_len;
    packet_buf = (guint8 *)g_malloc(buffer_len);

    if(exp_pdu_data->tlv_buffer_len > 0){
        memcpy(packet_buf, exp_pdu_data->tlv_buffer, exp_pdu_data->tlv_buffer_len);
        g_free(exp_pdu_data->tlv_buffer);
    }
    if(exp_pdu_data->tvb_captured_length > 0){
        tvb_memcpy(exp_pdu_data->pdu_tvb, packet_buf+exp_pdu_data->tlv_buffer_len, 0, exp_pdu_data->tvb_captured_length);
    }
    pkthdr.rec_type  = REC_TYPE_PACKET;
    pkthdr.ts.secs   = pinfo->abs_ts.secs;
    pkthdr.ts.nsecs  = pinfo->abs_ts.nsecs;
    pkthdr.caplen    = buffer_len;
    pkthdr.len       = exp_pdu_data->tvb_reported_length + exp_pdu_data->tlv_buffer_len;

    pkthdr.pkt_encap = exp_pdu_tap_data->pkt_encap;

    if (pinfo->fd->flags.has_user_comment)
        pkthdr.opt_comment = g_strdup(epan_get_user_comment(edt->session, pinfo->fd));
    else if (pinfo->fd->flags.has_phdr_comment)
        pkthdr.opt_comment = g_strdup(pinfo->phdr->opt_comment);

    pkthdr.presence_flags = WTAP_HAS_CAP_LEN|WTAP_HAS_INTERFACE_ID|WTAP_HAS_TS|WTAP_HAS_PACK_FLAGS;

    /* XXX: should the pkthdr.pseudo_header be set to the pinfo's pseudo-header? */
    /* XXX: report errors! */
    if (!wtap_dump(exp_pdu_tap_data->wdh, &pkthdr, packet_buf, &err, &err_info)) {
        switch (err) {

        case WTAP_ERR_UNWRITABLE_REC_DATA:
            g_free(err_info);
            break;

        default:
            break;
        }
    }

    g_free(packet_buf);
    g_free(pkthdr.opt_comment);

    return FALSE; /* Do not redraw */
}

int
exp_pdu_open(exp_pdu_t *exp_pdu_tap_data, int fd, char *comment)
{

    int   err;

    /* pcapng defs */
    wtap_optionblock_t           shb_hdr;
    wtapng_iface_descriptions_t *idb_inf;
    wtap_optionblock_t           int_data;
    wtapng_if_descr_mandatory_t *int_data_mand;
    GString                     *os_info_str;
    gsize                        opt_len;

    /* Create data for SHB  */
    os_info_str = g_string_new("");
    get_os_version_info(os_info_str);

    shb_hdr = wtap_optionblock_create(WTAP_OPTION_BLOCK_NG_SECTION);

    /* options */
    wtap_optionblock_set_option_string(shb_hdr, OPT_COMMENT, comment, strlen(comment));
    g_free(comment);

    /*
     * UTF-8 string containing the name of the operating system used to create
     * this section.
     */
    opt_len = os_info_str->len;
    wtap_optionblock_set_option_string(shb_hdr, OPT_SHB_OS, g_string_free(os_info_str, TRUE), opt_len);
    /*
     * UTF-8 string containing the name of the application used to create
     * this section.
     */
    wtap_optionblock_set_option_string_format(shb_hdr, OPT_SHB_USERAPPL, "Wireshark %s", get_ws_vcs_version_info());

    /* Create fake IDB info */
    idb_inf = g_new(wtapng_iface_descriptions_t,1);
    idb_inf->interface_data = g_array_new(FALSE, FALSE, sizeof(wtap_optionblock_t));

    /* create the fake interface data */
    int_data = wtap_optionblock_create(WTAP_OPTION_BLOCK_IF_DESCR);
    int_data_mand = (wtapng_if_descr_mandatory_t*)wtap_optionblock_get_mandatory_data(int_data);
    int_data_mand->wtap_encap      = WTAP_ENCAP_WIRESHARK_UPPER_PDU;
    int_data_mand->time_units_per_second = 1000000000; /* default nanosecond resolution */
    int_data_mand->link_type       = wtap_wtap_encap_to_pcap_encap(WTAP_ENCAP_WIRESHARK_UPPER_PDU);
    int_data_mand->snap_len        = WTAP_MAX_PACKET_SIZE;

    wtap_optionblock_set_option_string(int_data, OPT_IDB_NAME, "Fake IF, PDU->Export", strlen("Fake IF, PDU->Export"));
    wtap_optionblock_set_option_uint8(int_data, OPT_IDB_TSRESOL, 9);

    g_array_append_val(idb_inf->interface_data, int_data);

    /* Use a random name for the temporary import buffer */
    exp_pdu_tap_data->wdh = wtap_dump_fdopen_ng(fd, WTAP_FILE_TYPE_SUBTYPE_PCAPNG, WTAP_ENCAP_WIRESHARK_UPPER_PDU, WTAP_MAX_PACKET_SIZE, FALSE,
        shb_hdr, idb_inf, NULL, &err);
    if (exp_pdu_tap_data->wdh == NULL) {
        g_assert(err != 0);
        return err;
    }

    return 0;
}

int
exp_pdu_close(exp_pdu_t *exp_pdu_tap_data)
{
    int err = 0;
    if (!wtap_dump_close(exp_pdu_tap_data->wdh, &err))
        g_assert(err != 0);

    remove_tap_listener(exp_pdu_tap_data);
    return err;
}


char *
exp_pdu_pre_open(const char *tap_name, const char *filter, exp_pdu_t *exp_pdu_tap_data)
{
    GString        *error_string;

    /* XXX: can we always assume WTAP_ENCAP_WIRESHARK_UPPER_PDU? */
    exp_pdu_tap_data->pkt_encap = wtap_wtap_encap_to_pcap_encap(WTAP_ENCAP_WIRESHARK_UPPER_PDU);

    /* Register this tap listener now */
    error_string = register_tap_listener(tap_name,             /* The name of the tap we want to listen to */
                                         exp_pdu_tap_data,     /* instance identifier/pointer to a struct holding
                                                                * all state variables */
                                         filter,               /* pointer to a filter string */
                                         TL_REQUIRES_PROTO_TREE,  /* flags for the tap listener */
                                         NULL,
                                         export_pdu_packet,
                                         NULL);
    if (error_string != NULL)
        return g_string_free(error_string, FALSE);

    return NULL;
}


/*
 * Editor modelines
 *
 * 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:
 */