diff options
Diffstat (limited to 'ui/tap_export_pdu.c')
| -rw-r--r-- | ui/tap_export_pdu.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/ui/tap_export_pdu.c b/ui/tap_export_pdu.c new file mode 100644 index 00000000..912884d0 --- /dev/null +++ b/ui/tap_export_pdu.c @@ -0,0 +1,232 @@ +/* tap_export_pdu.c + * Routines for exporting PDUs to file + * + * 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/tap.h> +#include <epan/exported_pdu.h> +#include <epan/epan_dissect.h> +#include <wiretap/wtap.h> +#include <wiretap/wtap_opttypes.h> +#include <wsutil/os_version_info.h> +#include <wsutil/report_message.h> +#include "wsutil/version_info.h" + +#include "tap_export_pdu.h" + +/* Main entry point to the tap */ +static tap_packet_status +export_pdu_packet(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const void *data, tap_flags_t flags _U_) +{ + 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; + wtap_rec rec; + int err; + gchar *err_info; + int buffer_len; + guint8 *packet_buf; + tap_packet_status status = TAP_PACKET_DONT_REDRAW; /* no GUI, nothing to redraw */ + + /* + * Count this packet. + */ + exp_pdu_tap_data->framenum++; + + memset(&rec, 0, sizeof rec); + 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); + } + 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); + } + rec.rec_type = REC_TYPE_PACKET; + rec.presence_flags = WTAP_HAS_CAP_LEN|WTAP_HAS_INTERFACE_ID|WTAP_HAS_TS; + rec.ts.secs = pinfo->abs_ts.secs; + rec.ts.nsecs = pinfo->abs_ts.nsecs; + rec.rec_header.packet_header.caplen = buffer_len; + rec.rec_header.packet_header.len = exp_pdu_data->tvb_reported_length + exp_pdu_data->tlv_buffer_len; + + rec.rec_header.packet_header.pkt_encap = exp_pdu_tap_data->pkt_encap; + + /* rec.opt_block is not modified by wtap_dump, but if for some reason the + * epan_get_modified_block() or pinfo->rec->block are invalidated, + * copying it here does not hurt. (Can invalidation really happen?) */ + if (pinfo->fd->has_modified_block) { + rec.block = epan_get_modified_block(edt->session, pinfo->fd); + rec.block_was_modified = TRUE; + } else { + rec.block = pinfo->rec->block; + } + + /* XXX: should the rec.rec_header.packet_header.pseudo_header be set to the pinfo's pseudo-header? */ + if (!wtap_dump(exp_pdu_tap_data->wdh, &rec, packet_buf, &err, &err_info)) { + report_cfile_write_failure(NULL, exp_pdu_tap_data->pathname, + err, err_info, exp_pdu_tap_data->framenum, + wtap_dump_file_type_subtype(exp_pdu_tap_data->wdh)); + status = TAP_PACKET_FAILED; + } + + g_free(packet_buf); + + return status; +} + +gboolean +exp_pdu_open(exp_pdu_t *exp_pdu_tap_data, char *pathname, + int file_type_subtype, int fd, const char *comment, + int *err, gchar **err_info) +{ + /* pcapng defs */ + wtap_block_t shb_hdr; + wtap_block_t int_data; + wtapng_if_descr_mandatory_t *int_data_mand; + GString *os_info_str; + gsize opt_len; + gchar *opt_str; + + /* + * If the file format supports a section block, and the section + * block supports comments, create data for it. + */ + if (wtap_file_type_subtype_supports_block(file_type_subtype, + WTAP_BLOCK_SECTION) != BLOCK_NOT_SUPPORTED && + wtap_file_type_subtype_supports_option(file_type_subtype, + WTAP_BLOCK_SECTION, + OPT_COMMENT) != OPTION_NOT_SUPPORTED) { + os_info_str = g_string_new(""); + get_os_version_info(os_info_str); + + shb_hdr = wtap_block_create(WTAP_BLOCK_SECTION); + + /* options */ + wtap_block_add_string_option(shb_hdr, OPT_COMMENT, comment, strlen(comment)); + + /* + * UTF-8 string containing the name of the operating system used to + * create this section. + */ + opt_len = os_info_str->len; + opt_str = g_string_free(os_info_str, FALSE); + if (opt_str) { + wtap_block_add_string_option(shb_hdr, OPT_SHB_OS, opt_str, opt_len); + g_free(opt_str); + } + /* + * UTF-8 string containing the name of the application used to create + * this section. + */ + wtap_block_add_string_option_format(shb_hdr, OPT_SHB_USERAPPL, "%s", + get_appname_and_version()); + + exp_pdu_tap_data->shb_hdrs = g_array_new(FALSE, FALSE, sizeof(wtap_block_t)); + g_array_append_val(exp_pdu_tap_data->shb_hdrs, shb_hdr); + } else { + exp_pdu_tap_data->shb_hdrs = NULL; + } + + /* + * Create fake interface information for files that support (meaning + * "require") interface information and per-packet interface IDs. + */ + if (wtap_file_type_subtype_supports_block(file_type_subtype, + WTAP_BLOCK_IF_ID_AND_INFO) != BLOCK_NOT_SUPPORTED) { + exp_pdu_tap_data->idb_inf = g_new(wtapng_iface_descriptions_t,1); + exp_pdu_tap_data->idb_inf->interface_data = g_array_new(FALSE, FALSE, sizeof(wtap_block_t)); + + /* create the fake interface data */ + int_data = wtap_block_create(WTAP_BLOCK_IF_ID_AND_INFO); + int_data_mand = (wtapng_if_descr_mandatory_t*)wtap_block_get_mandatory_data(int_data); + int_data_mand->wtap_encap = exp_pdu_tap_data->pkt_encap; + int_data_mand->time_units_per_second = 1000000000; /* default nanosecond resolution */ + int_data_mand->snap_len = WTAP_MAX_PACKET_SIZE_STANDARD; + + wtap_block_add_string_option(int_data, OPT_IDB_NAME, "Fake IF, PDU->Export", strlen("Fake IF, PDU->Export")); + wtap_block_add_uint8_option(int_data, OPT_IDB_TSRESOL, 9); + + g_array_append_val(exp_pdu_tap_data->idb_inf->interface_data, int_data); + } else { + exp_pdu_tap_data->idb_inf = NULL; + } + + const wtap_dump_params params = { + .encap = exp_pdu_tap_data->pkt_encap, + .snaplen = WTAP_MAX_PACKET_SIZE_STANDARD, + .shb_hdrs = exp_pdu_tap_data->shb_hdrs, + .idb_inf = exp_pdu_tap_data->idb_inf, + }; + if (fd == 1) { + exp_pdu_tap_data->wdh = wtap_dump_open_stdout(file_type_subtype, + WTAP_UNCOMPRESSED, ¶ms, err, err_info); + } else { + exp_pdu_tap_data->wdh = wtap_dump_fdopen(fd, file_type_subtype, + WTAP_UNCOMPRESSED, ¶ms, err, err_info); + } + if (exp_pdu_tap_data->wdh == NULL) + return FALSE; + + exp_pdu_tap_data->pathname = pathname; + exp_pdu_tap_data->framenum = 0; /* No frames written yet */ + return TRUE; +} + +gboolean +exp_pdu_close(exp_pdu_t *exp_pdu_tap_data, int *err, gchar **err_info) +{ + gboolean status; + + status = wtap_dump_close(exp_pdu_tap_data->wdh, NULL, err, err_info); + + wtap_block_array_free(exp_pdu_tap_data->shb_hdrs); + wtap_free_idb_info(exp_pdu_tap_data->idb_inf); + + remove_tap_listener(exp_pdu_tap_data); + return status; +} + + +char * +exp_pdu_pre_open(const char *tap_name, const char *filter, exp_pdu_t *exp_pdu_tap_data) +{ + GString *error_string; + + /* Make sure tap is suitable for exported PDUs */ + gboolean found = FALSE; + for (GSList *export_pdu_tap_name_list = get_export_pdu_tap_list(); + export_pdu_tap_name_list != NULL; + export_pdu_tap_name_list = g_slist_next(export_pdu_tap_name_list)) { + if (strcmp((const char*)(export_pdu_tap_name_list->data), tap_name) == 0) { + found = TRUE; + break; + } + } + if (!found) { + return g_strdup("unsuitable for PDU export"); + } + + /* 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, + NULL); + if (error_string != NULL) + return g_string_free(error_string, FALSE); + + exp_pdu_tap_data->pkt_encap = export_pdu_tap_get_encap(tap_name); + + return NULL; +} |