wireshark/ui/text_import.c

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/* text_import.c
* State machine for text import
* November 2010, Jaap Keuter <jaap.keuter@xs4all.nl>
* Modified March 2021, Paul Weiß <paulniklasweiss@gmail.com>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* Based on text2pcap.c by Ashok Narayanan <ashokn@cisco.com>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
/*******************************************************************************
*
* This code reads in an ASCII hexdump of this common format:
*
* 00000000 00 E0 1E A7 05 6F 00 10 5A A0 B9 12 08 00 46 00 .....o..Z.....F.
* 00000010 03 68 00 00 00 00 0A 2E EE 33 0F 19 08 7F 0F 19 .h.......3......
* 00000020 03 80 94 04 00 00 10 01 16 A2 0A 00 03 50 00 0C .............P..
* 00000030 01 01 0F 19 03 80 11 01 1E 61 00 0C 03 01 0F 19 .........a......
*
* Each bytestring line consists of an offset, one or more bytes, and
* text at the end. An offset is defined as a hex string of more than
* two characters. A byte is defined as a hex string of exactly two
* characters. The text at the end is ignored, as is any text before
* the offset. Bytes read from a bytestring line are added to the
* current packet only if all the following conditions are satisfied:
*
* - No text appears between the offset and the bytes (any bytes appearing after
* such text would be ignored)
*
* - The offset must be arithmetically correct, i.e. if the offset is 00000020,
* then exactly 32 bytes must have been read into this packet before this.
* If the offset is wrong, the packet is immediately terminated
*
* A packet start is signaled by a zero offset.
*
* Lines starting with #TEXT2PCAP are directives. These allow the user
* to embed instructions into the capture file which allows text2pcap
* to take some actions (e.g. specifying the encapsulation
* etc.). Currently no directives are implemented.
*
* Lines beginning with # which are not directives are ignored as
* comments. Currently all non-hexdump text is ignored by text2pcap;
* in the future, text processing may be added, but lines prefixed
* with '#' will still be ignored.
*
* The output is a libpcap packet containing Ethernet frames by
* default. This program takes options which allow the user to add
* dummy Ethernet, IP and UDP, TCP or SCTP headers to the packets in order
* to allow dumps of L3 or higher protocols to be decoded.
*
* Considerable flexibility is built into this code to read hexdumps
* of slightly different formats. For example, any text prefixing the
* hexdump line is dropped (including mail forwarding '>'). The offset
* can be any hex number of four digits or greater.
*
* This converter cannot read a single packet greater than
* WTAP_MAX_PACKET_SIZE_STANDARD. The snapshot length is automatically
* set to WTAP_MAX_PACKET_SIZE_STANDARD.
*/
/*******************************************************************************
* Alternatively this parses a Textfile based on a prel regex containing named
* capturing groups like so:
* (?<seqno>\d+)\s*(?<dir><|>)\s*(?<time>\d+:\d\d:\d\d.\d+)\s+(?<data>[0-9a-fA-F]+)\\s+
*
* Fields are decoded using a leanient parser, but only one attempt is made.
* Except for in data invalid values will be replaced by default ones.
* data currently only accepts plain HEX, OCT or BIN encoded data.
* common field seperators are ignored. Note however that 0x or 0b prefixing is
* not supported and no automatic format detection is attempted.
*/
#include "config.h"
/*
* Just make sure we include the prototype for strptime as well
* (needed for glibc 2.2) but make sure we do this only if not
* yet defined.
*/
#ifndef __USE_XOPEN
# define __USE_XOPEN
#endif
#ifndef _XOPEN_SOURCE
# ifndef __sun
# define _XOPEN_SOURCE 600
# endif
#endif
/*
* Defining _XOPEN_SOURCE is needed on some platforms, e.g. platforms
* using glibc, to expand the set of things system header files define.
*
* Unfortunately, on other platforms, such as some versions of Solaris
* (including Solaris 10), it *reduces* that set as well, causing
* strptime() not to be declared, presumably because the version of the
* X/Open spec that _XOPEN_SOURCE implies doesn't include strptime() and
* blah blah blah namespace pollution blah blah blah.
*
* So we define __EXTENSIONS__ so that "strptime()" is declared.
*/
#ifndef __EXTENSIONS__
# define __EXTENSIONS__
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wsutil/file_util.h>
#include <time.h>
#include <glib.h>
#include <errno.h>
#include <assert.h>
#include <epan/tvbuff.h>
#include <wsutil/crc32.h>
#include <epan/in_cksum.h>
#ifndef HAVE_STRPTIME
# include "wsutil/strptime.h"
#endif
#include "text_import.h"
#include "text_import_scanner.h"
#include "text_import_scanner_lex.h"
#include "text_import_regex.h"
/*--- Options --------------------------------------------------------------------*/
/* Debug level */
static int debug = 0;
/* time percision stored in file: 1[file] = 1^(-SUBSEC_PREC) */
#define SUBSEC_PREC 9
#define debug_printf(level, ...) \
if (debug >= (level)) { \
printf(__VA_ARGS__); \
}
/* Dummy Ethernet header */
static gboolean hdr_ethernet = FALSE;
static guint8 hdr_eth_dest_addr[6] = {0x20, 0x52, 0x45, 0x43, 0x56, 0x00};
static guint8 hdr_eth_src_addr[6] = {0x20, 0x53, 0x45, 0x4E, 0x44, 0x00};
static guint32 hdr_ethernet_proto = 0;
/* Dummy IP header */
static gboolean hdr_ip = FALSE;
static guint hdr_ip_proto = 0;
/* Dummy UDP header */
static gboolean hdr_udp = FALSE;
static guint32 hdr_dest_port = 0;
static guint32 hdr_src_port = 0;
/* Dummy TCP header */
static gboolean hdr_tcp = FALSE;
/* TCP sequence numbers when has_direction is true */
static guint32 tcp_in_seq_num = 0;
static guint32 tcp_out_seq_num = 0;
/* Dummy SCTP header */
static gboolean hdr_sctp = FALSE;
static guint32 hdr_sctp_src = 0;
static guint32 hdr_sctp_dest = 0;
static guint32 hdr_sctp_tag = 0;
/* Dummy DATA chunk header */
static gboolean hdr_data_chunk = FALSE;
static guint8 hdr_data_chunk_type = 0;
static guint8 hdr_data_chunk_bits = 3;
static guint32 hdr_data_chunk_tsn = 0;
static guint16 hdr_data_chunk_sid = 0;
static guint16 hdr_data_chunk_ssn = 0;
static guint32 hdr_data_chunk_ppid = 0;
/* Dummy ExportPdu header */
static gboolean hdr_export_pdu = FALSE;
static const gchar* hdr_export_pdu_payload = NULL;
static gboolean has_direction = FALSE;
static guint32 direction = PACK_FLAGS_RECEPTION_TYPE_UNSPECIFIED;
static gboolean has_seqno = FALSE;
static guint64 seqno = 0;
/*--- Local data -----------------------------------------------------------------*/
/* This is where we store the packet currently being built */
static guint8 *packet_buf;
static guint32 curr_offset = 0;
static guint32 max_offset = WTAP_MAX_PACKET_SIZE_STANDARD;
static guint32 packet_start = 0;
static void start_new_packet (void);
/* This buffer contains strings present before the packet offset 0 */
#define PACKET_PREAMBLE_MAX_LEN 2048
static guint8 packet_preamble[PACKET_PREAMBLE_MAX_LEN+1];
static int packet_preamble_len = 0;
/* Time code of packet, derived from packet_preamble */
static time_t ts_sec = 0;
static guint32 ts_nsec = 0;
static const char *ts_fmt = NULL;
static struct tm timecode_default;
static wtap_dumper* wdh;
/* HDR_ETH Offset base to parse */
static guint32 offset_base = 16;
/* ----- State machine -----------------------------------------------------------*/
/* Current state of parser */
typedef enum {
INIT, /* Waiting for start of new packet */
START_OF_LINE, /* Starting from beginning of line */
READ_OFFSET, /* Just read the offset */
READ_BYTE, /* Just read a byte */
READ_TEXT /* Just read text - ignore until EOL */
} parser_state_t;
static parser_state_t state = INIT;
static const char *state_str[] = {"Init",
"Start-of-line",
"Offset",
"Byte",
"Text"
};
static const char *token_str[] = {"",
"Byte",
"Offset",
"Directive",
"Text",
"End-of-line"
};
/* ----- Skeleton Packet Headers --------------------------------------------------*/
typedef struct {
guint8 dest_addr[6];
guint8 src_addr[6];
guint16 l3pid;
} hdr_ethernet_t;
static hdr_ethernet_t HDR_ETHERNET;
typedef struct {
guint8 ver_hdrlen;
guint8 dscp;
guint16 packet_length;
guint16 identification;
guint8 flags;
guint8 fragment;
guint8 ttl;
guint8 protocol;
guint16 hdr_checksum;
guint32 src_addr;
guint32 dest_addr;
} hdr_ip_t;
#if G_BYTE_ORDER == G_BIG_ENDIAN
#define IP_ID 0x1234
#define IP_SRC 0x01010101
#define IP_DST 0x02020202
#else
#define IP_ID 0x3412
#define IP_SRC 0x01010101
#define IP_DST 0x02020202
#endif
static hdr_ip_t HDR_IP =
{0x45, 0, 0, IP_ID, 0, 0, 0xff, 0, 0, IP_SRC, IP_DST};
static struct { /* pseudo header for checksum calculation */
guint32 src_addr;
guint32 dest_addr;
guint8 zero;
guint8 protocol;
guint16 length;
} pseudoh;
typedef struct {
guint16 source_port;
guint16 dest_port;
guint16 length;
guint16 checksum;
} hdr_udp_t;
static hdr_udp_t HDR_UDP = {0, 0, 0, 0};
typedef struct {
guint16 source_port;
guint16 dest_port;
guint32 seq_num;
guint32 ack_num;
guint8 hdr_length;
guint8 flags;
guint16 window;
guint16 checksum;
guint16 urg;
} hdr_tcp_t;
static hdr_tcp_t HDR_TCP = {0, 0, 0, 0, 0x50, 0, 0, 0, 0};
typedef struct {
guint16 src_port;
guint16 dest_port;
guint32 tag;
guint32 checksum;
} hdr_sctp_t;
static hdr_sctp_t HDR_SCTP = {0, 0, 0, 0};
typedef struct {
guint8 type;
guint8 bits;
guint16 length;
guint32 tsn;
guint16 sid;
guint16 ssn;
guint32 ppid;
} hdr_data_chunk_t;
static hdr_data_chunk_t HDR_DATA_CHUNK = {0, 0, 0, 0, 0, 0, 0};
typedef struct {
guint16 tag_type;
guint16 payload_len;
} hdr_export_pdu_t;
static hdr_export_pdu_t HDR_EXPORT_PDU = {0, 0};
#define EXPORT_PDU_END_OF_OPTIONS_SIZE 4
/* Link-layer type; see net/bpf.h for details */
static guint pcap_link_type = 1; /* Default is DLT_EN10MB */
/*----------------------------------------------------------------------
* Parse a single hex number
* Will abort the program if it can't parse the number
* Pass in TRUE if this is an offset, FALSE if not
*/
static guint32
parse_num (const char *str, int offset)
{
unsigned long num;
char *c;
if (str == NULL) {
fprintf(stderr, "FATAL ERROR: str is NULL\n");
exit(1);
}
num = strtoul(str, &c, offset ? offset_base : 16);
if (c == str) {
fprintf(stderr, "FATAL ERROR: Bad hex number? [%s]\n", str);
}
return (guint32)num;
}
/*----------------------------------------------------------------------
* Write this byte into current packet
*/
static void
write_byte (const char *str)
{
guint32 num;
num = parse_num(str, FALSE);
packet_buf[curr_offset] = (guint8) num;
curr_offset ++;
if (curr_offset >= max_offset) /* packet full */
start_new_packet();
}
/*----------------------------------------------------------------------
* Remove bytes from the current packet
*/
static void
unwrite_bytes (guint32 nbytes)
{
curr_offset -= nbytes;
}
/*----------------------------------------------------------------------
* Determine SCTP chunk padding length
*/
static guint32
number_of_padding_bytes (guint32 length)
{
guint32 remainder;
remainder = length % 4;
if (remainder == 0)
return 0;
else
return 4 - remainder;
}
/*----------------------------------------------------------------------
* Write current packet out
*/
static void
write_current_packet (void)
{
int prefix_length = 0;
int proto_length = 0;
int ip_length = 0;
int eth_trailer_length = 0;
int prefix_index = 0;
int i, padding_length;
if (curr_offset > 0) {
/* Write the packet */
/* Is direction indication on with an inbound packet? */
gboolean isOutbound = has_direction && (direction == PACK_FLAGS_DIRECTION_OUTBOUND);
/* Compute packet length */
prefix_length = 0;
if (hdr_export_pdu) {
prefix_length += (int)sizeof(HDR_EXPORT_PDU) + (int)strlen(hdr_export_pdu_payload) + EXPORT_PDU_END_OF_OPTIONS_SIZE;
proto_length = prefix_length + curr_offset;
}
if (hdr_data_chunk) { prefix_length += (int)sizeof(HDR_DATA_CHUNK); }
if (hdr_sctp) { prefix_length += (int)sizeof(HDR_SCTP); }
if (hdr_udp) { prefix_length += (int)sizeof(HDR_UDP); proto_length = prefix_length + curr_offset; }
if (hdr_tcp) { prefix_length += (int)sizeof(HDR_TCP); proto_length = prefix_length + curr_offset; }
if (hdr_ip) {
prefix_length += (int)sizeof(HDR_IP);
ip_length = prefix_length + curr_offset + ((hdr_data_chunk) ? number_of_padding_bytes(curr_offset) : 0);
}
if (hdr_ethernet) { prefix_length += (int)sizeof(HDR_ETHERNET); }
/* Make room for dummy header */
memmove(&packet_buf[prefix_length], packet_buf, curr_offset);
if (hdr_ethernet) {
/* Pad trailer */
if (prefix_length + curr_offset < 60) {
eth_trailer_length = 60 - (prefix_length + curr_offset);
}
}
/* Write Ethernet header */
if (hdr_ethernet) {
if (isOutbound)
{
memcpy(HDR_ETHERNET.dest_addr, hdr_eth_src_addr, 6);
memcpy(HDR_ETHERNET.src_addr, hdr_eth_dest_addr, 6);
} else {
memcpy(HDR_ETHERNET.dest_addr, hdr_eth_dest_addr, 6);
memcpy(HDR_ETHERNET.src_addr, hdr_eth_src_addr, 6);
}
HDR_ETHERNET.l3pid = g_htons(hdr_ethernet_proto);
memcpy(&packet_buf[prefix_index], &HDR_ETHERNET, sizeof(HDR_ETHERNET));
prefix_index += (int)sizeof(HDR_ETHERNET);
}
/* Write IP header */
if (hdr_ip) {
vec_t cksum_vector[1];
if (isOutbound) {
HDR_IP.src_addr = IP_DST;
HDR_IP.dest_addr = IP_SRC;
} else {
HDR_IP.src_addr = IP_SRC;
HDR_IP.dest_addr = IP_DST;
}
HDR_IP.packet_length = g_htons(ip_length);
HDR_IP.protocol = (guint8) hdr_ip_proto;
HDR_IP.hdr_checksum = 0;
cksum_vector[0].ptr = (guint8 *)&HDR_IP; cksum_vector[0].len = sizeof(HDR_IP);
HDR_IP.hdr_checksum = in_cksum(cksum_vector, 1);
memcpy(&packet_buf[prefix_index], &HDR_IP, sizeof(HDR_IP));
prefix_index += (int)sizeof(HDR_IP);
}
/* initialize pseudo header for checksum calculation */
pseudoh.src_addr = HDR_IP.src_addr;
pseudoh.dest_addr = HDR_IP.dest_addr;
pseudoh.zero = 0;
pseudoh.protocol = (guint8) hdr_ip_proto;
pseudoh.length = g_htons(proto_length);
/* Write UDP header */
if (hdr_udp) {
vec_t cksum_vector[3];
HDR_UDP.source_port = isOutbound ? g_htons(hdr_dest_port): g_htons(hdr_src_port);
HDR_UDP.dest_port = isOutbound ? g_htons(hdr_src_port) : g_htons(hdr_dest_port);
HDR_UDP.length = g_htons(proto_length);
HDR_UDP.checksum = 0;
cksum_vector[0].ptr = (guint8 *)&pseudoh; cksum_vector[0].len = sizeof(pseudoh);
cksum_vector[1].ptr = (guint8 *)&HDR_UDP; cksum_vector[1].len = sizeof(HDR_UDP);
cksum_vector[2].ptr = &packet_buf[prefix_length]; cksum_vector[2].len = curr_offset;
HDR_UDP.checksum = in_cksum(cksum_vector, 3);
memcpy(&packet_buf[prefix_index], &HDR_UDP, sizeof(HDR_UDP));
prefix_index += (int)sizeof(HDR_UDP);
}
/* Write TCP header */
if (hdr_tcp) {
vec_t cksum_vector[3];
HDR_TCP.source_port = isOutbound ? g_htons(hdr_dest_port): g_htons(hdr_src_port);
HDR_TCP.dest_port = isOutbound ? g_htons(hdr_src_port) : g_htons(hdr_dest_port);
/* set ack number if we have direction */
if (has_direction) {
HDR_TCP.flags = 0x10;
HDR_TCP.ack_num = g_ntohl(isOutbound ? tcp_out_seq_num : tcp_in_seq_num);
HDR_TCP.ack_num = g_htonl(HDR_TCP.ack_num);
}
else {
HDR_TCP.flags = 0;
HDR_TCP.ack_num = 0;
}
HDR_TCP.seq_num = isOutbound ? tcp_in_seq_num : tcp_out_seq_num;
HDR_TCP.window = g_htons(0x2000);
HDR_TCP.checksum = 0;
cksum_vector[0].ptr = (guint8 *)&pseudoh; cksum_vector[0].len = sizeof(pseudoh);
cksum_vector[1].ptr = (guint8 *)&HDR_TCP; cksum_vector[1].len = sizeof(HDR_TCP);
cksum_vector[2].ptr = &packet_buf[prefix_length]; cksum_vector[2].len = curr_offset;
HDR_TCP.checksum = in_cksum(cksum_vector, 3);
memcpy(&packet_buf[prefix_index], &HDR_TCP, sizeof(HDR_TCP));
prefix_index += (int)sizeof(HDR_TCP);
if (isOutbound) {
tcp_in_seq_num = g_ntohl(tcp_in_seq_num) + curr_offset;
tcp_in_seq_num = g_htonl(tcp_in_seq_num);
}
else {
tcp_out_seq_num = g_ntohl(tcp_out_seq_num) + curr_offset;
tcp_out_seq_num = g_htonl(tcp_out_seq_num);
}
}
/* Compute DATA chunk header and append padding */
if (hdr_data_chunk) {
HDR_DATA_CHUNK.type = hdr_data_chunk_type;
HDR_DATA_CHUNK.bits = hdr_data_chunk_bits;
HDR_DATA_CHUNK.length = g_htons(curr_offset + sizeof(HDR_DATA_CHUNK));
HDR_DATA_CHUNK.tsn = g_htonl(hdr_data_chunk_tsn);
HDR_DATA_CHUNK.sid = g_htons(hdr_data_chunk_sid);
HDR_DATA_CHUNK.ssn = g_htons(hdr_data_chunk_ssn);
HDR_DATA_CHUNK.ppid = g_htonl(hdr_data_chunk_ppid);
padding_length = number_of_padding_bytes(curr_offset);
for (i=0; i<padding_length; i++)
packet_buf[prefix_length+curr_offset+i] = 0;
curr_offset += padding_length;
}
/* Write SCTP header */
if (hdr_sctp) {
HDR_SCTP.src_port = isOutbound ? g_htons(hdr_sctp_dest): g_htons(hdr_sctp_src);
HDR_SCTP.dest_port = isOutbound ? g_htons(hdr_sctp_src) : g_htons(hdr_sctp_dest);
HDR_SCTP.tag = g_htonl(hdr_sctp_tag);
HDR_SCTP.checksum = g_htonl(0);
HDR_SCTP.checksum = crc32c_calculate(&HDR_SCTP, sizeof(HDR_SCTP), CRC32C_PRELOAD);
if (hdr_data_chunk)
HDR_SCTP.checksum = crc32c_calculate(&HDR_DATA_CHUNK, sizeof(HDR_DATA_CHUNK), HDR_SCTP.checksum);
HDR_SCTP.checksum = g_htonl(~crc32c_calculate(&packet_buf[prefix_length], curr_offset, HDR_SCTP.checksum));
memcpy(&packet_buf[prefix_index], &HDR_SCTP, sizeof(HDR_SCTP));
prefix_index += (int)sizeof(HDR_SCTP);
}
/* Write DATA chunk header */
if (hdr_data_chunk) {
memcpy(&packet_buf[prefix_index], &HDR_DATA_CHUNK, sizeof(HDR_DATA_CHUNK));
/*prefix_index += (int)sizeof(HDR_DATA_CHUNK);*/
}
/* Write ExportPDU header */
if (hdr_export_pdu) {
guint payload_len = (guint)strlen(hdr_export_pdu_payload);
HDR_EXPORT_PDU.tag_type = g_htons(0x0c); // EXP_PDU_TAG_PROTO_NAME;
HDR_EXPORT_PDU.payload_len = g_htons(payload_len);
memcpy(&packet_buf[prefix_index], &HDR_EXPORT_PDU, sizeof(HDR_EXPORT_PDU));
prefix_index += sizeof(HDR_EXPORT_PDU);
memcpy(&packet_buf[prefix_index], hdr_export_pdu_payload, payload_len);
prefix_index += payload_len;
/* Add end-of-options tag */
memset(&packet_buf[prefix_index], 0x00, 4);
}
/* Write Ethernet trailer */
if (hdr_ethernet && eth_trailer_length > 0) {
memset(&packet_buf[prefix_length+curr_offset], 0, eth_trailer_length);
}
HDR_TCP.seq_num = g_ntohl(HDR_TCP.seq_num) + curr_offset;
HDR_TCP.seq_num = g_htonl(HDR_TCP.seq_num);
{
/* Write the packet */
wtap_rec rec;
int err;
gchar *err_info;
memset(&rec, 0, sizeof rec);
rec.rec_type = REC_TYPE_PACKET;
rec.ts.secs = (guint32)ts_sec;
rec.ts.nsecs = ts_nsec;
if (ts_fmt == NULL) { ts_nsec++; } /* fake packet counter */
rec.rec_header.packet_header.caplen = rec.rec_header.packet_header.len = prefix_length + curr_offset + eth_trailer_length;
rec.rec_header.packet_header.pkt_encap = pcap_link_type;
rec.rec_header.packet_header.pack_flags |= direction;
rec.presence_flags = WTAP_HAS_CAP_LEN|WTAP_HAS_INTERFACE_ID|WTAP_HAS_TS|WTAP_HAS_PACK_FLAGS;
if (has_seqno) {
rec.presence_flags |= WTAP_HAS_PACKET_ID;
rec.rec_header.packet_header.packet_id = seqno;
}
/* XXX - report errors! */
if (!wtap_dump(wdh, &rec, packet_buf, &err, &err_info)) {
switch (err) {
case WTAP_ERR_UNWRITABLE_REC_DATA:
g_free(err_info);
break;
default:
break;
}
}
}
}
packet_start += curr_offset;
curr_offset = 0;
}
/*----------------------------------------------------------------------
* Append a token to the packet preamble.
*/
static void
append_to_preamble(char *str)
{
size_t toklen;
if (packet_preamble_len != 0) {
if (packet_preamble_len == PACKET_PREAMBLE_MAX_LEN)
return; /* no room to add more preamble */
/* Add a blank separator between the previous token and this token. */
packet_preamble[packet_preamble_len++] = ' ';
}
if(str == NULL){
fprintf(stderr, "FATAL ERROR: str is NULL\n");
exit(1);
}
toklen = strlen(str);
if (toklen != 0) {
if (packet_preamble_len + toklen > PACKET_PREAMBLE_MAX_LEN)
return; /* no room to add the token to the preamble */
g_strlcpy(&packet_preamble[packet_preamble_len], str, PACKET_PREAMBLE_MAX_LEN);
packet_preamble_len += (int) toklen;
if (debug >= 2) {
char *c;
char xs[PACKET_PREAMBLE_MAX_LEN];
g_strlcpy(xs, packet_preamble, PACKET_PREAMBLE_MAX_LEN);
while ((c = strchr(xs, '\r')) != NULL) *c=' ';
fprintf (stderr, "[[append_to_preamble: \"%s\"]]", xs);
}
}
}
#define INVALID_VALUE (-1)
#define WHITESPACE_VALUE (-2)
/*
* Information on how to parse any plainly encoded binary data
*
* one Unit is least_common_mmultiple(bits_per_char, 8) bits.
*/
struct plain_decoding_data {
const gchar* name;
guint chars_per_unit;
guint bytes_per_unit : 3; /* Internally a guint64 is used to hold units */
guint bits_per_char : 6;
gint8 table[256];
};
#define _INVALID_INIT2 INVALID_VALUE, INVALID_VALUE
#define _INVALID_INIT4 _INVALID_INIT2, _INVALID_INIT2
#define _INVALID_INIT8 _INVALID_INIT4, _INVALID_INIT4
#define _INVALID_INIT16 _INVALID_INIT8, _INVALID_INIT8
#define _INVALID_INIT32 _INVALID_INIT16, _INVALID_INIT16
#define _INVALID_INIT64 _INVALID_INIT32, _INVALID_INIT32
#define _INVALID_INIT128 _INVALID_INIT64, _INVALID_INIT64
#define _INVALID_INIT256 _INVALID_INIT128, _INVALID_INIT128
#define INVALID_INIT _INVALID_INIT256
// this is a gcc/clang extension:
// [0 ... 255] = INVALID_VALUE
#define WHITESPACE_INIT \
[' '] = WHITESPACE_VALUE, \
['\t'] = WHITESPACE_VALUE, \
['\n'] = WHITESPACE_VALUE, \
['\v'] = WHITESPACE_VALUE, \
['\f'] = WHITESPACE_VALUE, \
['\r'] = WHITESPACE_VALUE
/*
* Some compilers warn about initializing the same subobject
* more than once with designated initializers.
*
* We're doing that - INVALID_INIT iniitalizes everything to
* INVALID_VALUE, but then we override selected elements -
* but we know what we're doing, so just suppress that
* warning.
*/
DIAG_OFF_INIT_TWICE
const struct plain_decoding_data hex_decode_info = {
.chars_per_unit = 2,
.bytes_per_unit = 1,
.bits_per_char = 4,
.table = {
INVALID_INIT,
WHITESPACE_INIT,
[':'] = WHITESPACE_VALUE,
['0'] = 0,1,2,3,4,5,6,7,8,9,
['A'] = 10,11,12,13,14,15,
['a'] = 10,11,12,13,14,15
}
};
const struct plain_decoding_data bin_decode_info = {
.chars_per_unit = 8,
.bytes_per_unit = 1,
.bits_per_char = 1,
.table = {
INVALID_INIT,
WHITESPACE_INIT,
['0'] = 0, 1
}
};
const struct plain_decoding_data oct_decode_info = {
.chars_per_unit = 8,
.bytes_per_unit = 3,
.bits_per_char = 3,
.table = {
INVALID_INIT,
WHITESPACE_INIT,
['0'] = 0,1,2,3,4,5,6,7
}
};
const struct plain_decoding_data base64_decode_info = {
.chars_per_unit = 4,
.bytes_per_unit = 3,
.bits_per_char = 6,
.table = {
INVALID_INIT,
WHITESPACE_INIT,
['A'] = 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,
['a'] = 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,
['0'] = 52,53,54,55,56,57,58,59,60,61,
['+'] = 62,
['/'] = 63,
['='] = WHITESPACE_VALUE /* padding at the end, the decoder doesn't need this, so just ignores it */
}
};
DIAG_ON_INIT_TWICE
/*******************************************************************************
* The modularized part of this mess, used by the wrapper around the regex
* engine in text_import_regex.c to hook into this state-machine backend.
*
* Should the rest be modularized aswell? Maybe, but then start with pcap2text.c
*/
/**
* This function parses encoded data according to <encoding> into binary data.
* It will continue until one of the following conditions is met:
* - src is depletetd
* - dest cannot hold another full unit of data
* - an invalid character is read
* When this happens any complete bytes will be recovered from the remaining
* possibly incomplete unit and stored to dest (there will be no incomplete unit
* if dest is full). Any remaining bits will be discarded.
* src and dest will be advanced to where parsing including this last incomplete
* unit stopped.
* If you want to continue parsing (meaning incomplete units were due to call
* fragmentation and not actually due to EOT) you have to resume the parser at
* *src_last_unit and dest - result % bytes_per_unit
*/
static int parse_plain_data(guchar** src, const guchar* src_end,
guint8** dest, const guint8* dest_end, const struct plain_decoding_data* encoding,
guchar** src_last_unit) {
int status = 1;
int units = 0;
/* unit buffer */
guint64 c_val = 0;
guint c_chars = 0;
/**
* Src data |- - -|- - -|- - -|- - -|- - -|- - -|- - -|- - -|
* Bytes |- - - - - - - -|- - - - - - - -|- - - - - - - -|
* Units |- - - - - - - - - - - - - - - - - - - - - - - -|
*/
guint64 val;
int j;
debug_printf(3, "parsing data: ");
while (*src < src_end && *dest + encoding->bytes_per_unit <= dest_end) {
debug_printf(3, "%c", **src);
val = encoding->table[**src];
switch (val) {
case INVALID_VALUE:
status = -1;
goto remainder;
case WHITESPACE_VALUE:
fprintf(stderr, "Unexpected char %d in data\n", **src);
break;
default:
c_val = c_val << encoding->bits_per_char | val;
++c_chars;
/* another full unit */
if (c_chars == encoding->chars_per_unit) {
++units;
if (src_last_unit)
*src_last_unit = *src;
c_chars = 0;
for (j = encoding->bytes_per_unit; j > 0; --j) {
**dest = (gchar) (c_val >> (j * 8 - 8));
*dest += 1;
}
}
}
*src += 1;
}
remainder:
for (j = c_chars * encoding->bits_per_char; j >= 8; j -= 8) {
**dest = (gchar) (c_val >> (j - 8));
*dest += 1;
}
debug_printf(3, "\n");
return status * units;
}
void parse_data(guchar* start_field, guchar* end_field, enum data_encoding encoding) {
guint8* dest = &packet_buf[curr_offset];
guint8* dest_end = &packet_buf[max_offset];
const struct plain_decoding_data* table; /* should be further down */
switch (encoding) {
case ENCODING_PLAIN_HEX:
case ENCODING_PLAIN_OCT:
case ENCODING_PLAIN_BIN:
case ENCODING_BASE64:
/* const struct plain_decoding_data* table; // This can't be here because gcc says no */
switch (encoding) {
case ENCODING_PLAIN_HEX:
table = &hex_decode_info;
break;
case ENCODING_PLAIN_OCT:
table = &oct_decode_info;
break;
case ENCODING_PLAIN_BIN:
table = &bin_decode_info;
break;
case ENCODING_BASE64:
table = &base64_decode_info;
break;
default:
return;
}
while (1) {
parse_plain_data(&start_field, end_field, &dest, dest_end, table, NULL);
curr_offset = (int) (dest - packet_buf);
if (curr_offset == max_offset) {
write_current_packet();
dest = &packet_buf[curr_offset];
} else
break;
}
break;
default:
fprintf(stderr, "not implemented/invalid encoding type\n");
return;
}
}
#define setFlags(VAL, MASK, FLAGS) \
((VAL) & ~(MASK)) | ((FLAGS) & (MASK))
static void _parse_dir(const guchar* start_field, const guchar* end_field _U_, const gchar* in_indicator, const gchar* out_indicator, guint32* dir) {
for (; *in_indicator && *start_field != *in_indicator; ++in_indicator);
if (*in_indicator) {
*dir = setFlags(*dir, PACK_FLAGS_DIRECTION_MASK << PACK_FLAGS_DIRECTION_SHIFT, PACK_FLAGS_DIRECTION_INBOUND);
return;
}
for (; *out_indicator && *start_field != *out_indicator; ++out_indicator);
if (*out_indicator) {
*dir = setFlags(*dir, PACK_FLAGS_DIRECTION_MASK << PACK_FLAGS_DIRECTION_SHIFT, PACK_FLAGS_DIRECTION_OUTBOUND);
return;
}
*dir = setFlags(*dir, PACK_FLAGS_DIRECTION_MASK << PACK_FLAGS_DIRECTION_SHIFT, PACK_FLAGS_DIRECTION_UNKNOWN);
}
void parse_dir(const guchar* start_field, const guchar* end_field, const gchar* in_indicator, const gchar* out_indicator) {
_parse_dir(start_field, end_field, in_indicator, out_indicator, &direction);
}
#define PARSE_BUF 64
static void _parse_time(const guchar* start_field, const guchar* end_field, const gchar* _format, time_t* sec, gint* nsec) {
struct tm timecode;
time_t sec_buf;
gint nsec_buf;
char field[PARSE_BUF];
char format[PARSE_BUF];
char* subsecs_fmt;
int subseclen = -1;
char *cursor;
char *p;
int i;
g_strlcpy(field, start_field, MIN(end_field - start_field + 1, PARSE_BUF));
g_strlcpy(format, _format, PARSE_BUF);
/*
* Initialize to today localtime, just in case not all fields
* of the date and time are specified.
*/
timecode = timecode_default;
cursor = &field[0];
/*
* %f is for fractions of seconds not supported by strptime
* BTW: what is this function name? is this some russian joke?
*/
subsecs_fmt = g_strrstr (format, "%f");
if (subsecs_fmt)
*subsecs_fmt = 0;
else
/* arbitrary counter if no fractions */
++*nsec;
cursor = strptime(cursor, format, &timecode);
if (cursor != NULL && subsecs_fmt != NULL) {
/*
* Parse subsecs and any following format
*/
nsec_buf = (guint) strtol(cursor, &p, 10);
if (p > cursor) {
*nsec = nsec_buf;
subseclen = (int) (p - cursor);
cursor = p;
strptime(cursor, subsecs_fmt + 2, &timecode);
} else {
++*nsec;
subseclen = -1;
}
}
if (subseclen > 0) {
/*
* Convert that number to a number
* of nanoseconds; if it's N digits
* long, it's in units of 10^(-N) seconds,
* so, to convert it to units of
* 10^-9 seconds, we multiply by
* 10^(9-N).
*/
if (subseclen > SUBSEC_PREC) {
/*
* *More* than 9 digits; 9-N is
* negative, so we divide by
* 10^(N-9).
*/
for (i = subseclen - SUBSEC_PREC; i != 0; i--)
*nsec /= 10;
} else if (subseclen < SUBSEC_PREC) {
for (i = SUBSEC_PREC - subseclen; i != 0; i--)
*nsec *= 10;
}
}
if ( -1 == (sec_buf = mktime(&timecode)) ) {
++*sec;
} else {
*sec = sec_buf;
}
debug_printf(3, "parsed time %s Format(%s), time(%u), subsecs(%u)\n", field, _format, (guint32)*sec, (guint32)*nsec);
}
void parse_time(const guchar* start_field, const guchar* end_field, const gchar* format) {
_parse_time(start_field, end_field, format, &ts_sec, &ts_nsec);
}
void parse_seqno(const guchar* start_field, const guchar* end_field) {
char* buf = (char*) g_alloca(end_field - start_field + 1);
g_strlcpy(buf, start_field, end_field - start_field + 1);
seqno = g_ascii_strtoull(buf, NULL, 10);
}
void flush_packet(void) {
write_current_packet();
}
/*----------------------------------------------------------------------
* Parse the preamble to get the timecode.
*/
static void
parse_preamble (void)
{
int i;
/*
* Null-terminate the preamble.
*/
packet_preamble[packet_preamble_len] = '\0';
if (has_direction) {
_parse_dir(&packet_preamble[0], &packet_preamble[1], "iI", "oO", &direction);
i = 0;
while (packet_preamble[i] == ' ' ||
packet_preamble[i] == '\r' ||
packet_preamble[i] == '\t') {
i++;
}
packet_preamble_len -= i;
/* Also move the trailing '\0'. */
memmove(packet_preamble, packet_preamble + i, packet_preamble_len + 1);
}
/*
* If no time stamp format was specified, don't attempt to parse
* the packet preamble to extract a time stamp.
*/
if (ts_fmt == NULL)
return;
/*
* Initialize to today localtime, just in case not all fields
* of the date and time are specified.
*/
/* Ensure preamble has more than two chars before attempting to parse.
* This should cover line breaks etc that get counted.
*/
if ( strlen(packet_preamble) > 2 ) {
_parse_time(packet_preamble, packet_preamble + strlen(packet_preamble + 1), ts_fmt, &ts_sec, &ts_nsec);
}
if (debug >= 2) {
char *c;
while ((c = strchr(packet_preamble, '\r')) != NULL) *c=' ';
fprintf(stderr, "[[parse_preamble: \"%s\"]]\n", packet_preamble);
fprintf(stderr, "Format(%s), time(%u), subsecs(%u)\n", ts_fmt, (guint32)ts_sec, ts_nsec);
}
/* Clear Preamble */
packet_preamble_len = 0;
}
/*----------------------------------------------------------------------
* Start a new packet
*/
static void
start_new_packet (void)
{
if (debug>=1)
fprintf(stderr, "Start new packet\n");
/* Write out the current packet, if required */
write_current_packet();
/* Ensure we parse the packet preamble as it may contain the time */
/* THIS IMPLEIES A STATE TRANSITION OUTSIDE THE STATE MACHINE */
parse_preamble();
}
/*----------------------------------------------------------------------
* Process a directive
*/
static void
process_directive (char *str)
{
fprintf(stderr, "\n--- Directive [%s] currently unsupported ---\n", str+10);
}
/*----------------------------------------------------------------------
* Parse a single token (called from the scanner)
*/
void
parse_token (token_t token, char *str)
{
guint32 num;
/*
* This is implemented as a simple state machine of five states.
* State transitions are caused by tokens being received from the
* scanner. The code should be self_documenting.
*/
if (debug>=2) {
/* Sanitize - remove all '\r' */
char *c;
if (str!=NULL) { while ((c = strchr(str, '\r')) != NULL) *c=' '; }
fprintf(stderr, "(%s, %s \"%s\") -> (",
state_str[state], token_str[token], str ? str : "");
}
switch(state) {
/* ----- Waiting for new packet -------------------------------------------*/
case INIT:
switch(token) {
case T_TEXT:
append_to_preamble(str);
break;
case T_DIRECTIVE:
process_directive(str);
break;
case T_OFFSET:
num = parse_num(str, TRUE);
if (num==0) {
/* New packet starts here */
start_new_packet();
state = READ_OFFSET;
}
break;
case T_BYTE:
if (offset_base == 0) {
start_new_packet();
write_byte(str);
state = READ_BYTE;
}
break;
case T_EOF:
write_current_packet();
break;
default:
break;
}
break;
/* ----- Processing packet, start of new line -----------------------------*/
case START_OF_LINE:
switch(token) {
case T_TEXT:
append_to_preamble(str);
break;
case T_DIRECTIVE:
process_directive(str);
break;
case T_OFFSET:
num = parse_num(str, TRUE);
if (num==0) {
/* New packet starts here */
start_new_packet();
packet_start = 0;
state = READ_OFFSET;
} else if ((num - packet_start) != curr_offset) {
/*
* The offset we read isn't the one we expected.
* This may only mean that we mistakenly interpreted
* some text as byte values (e.g., if the text dump
* of packet data included a number with spaces around
* it). If the offset is less than what we expected,
* assume that's the problem, and throw away the putative
* extra byte values.
*/
if (num < curr_offset) {
unwrite_bytes(curr_offset - num);
state = READ_OFFSET;
} else {
/* Bad offset; switch to INIT state */
if (debug>=1)
fprintf(stderr, "Inconsistent offset. Expecting %0X, got %0X. Ignoring rest of packet\n",
curr_offset, num);
write_current_packet();
state = INIT;
}
} else
state = READ_OFFSET;
break;
case T_BYTE:
if (offset_base == 0) {
write_byte(str);
state = READ_BYTE;
}
break;
case T_EOF:
write_current_packet();
break;
default:
break;
}
break;
/* ----- Processing packet, read offset -----------------------------------*/
case READ_OFFSET:
switch(token) {
case T_BYTE:
/* Record the byte */
state = READ_BYTE;
write_byte(str);
break;
case T_TEXT:
case T_DIRECTIVE:
case T_OFFSET:
state = READ_TEXT;
break;
case T_EOL:
state = START_OF_LINE;
break;
case T_EOF:
write_current_packet();
break;
default:
break;
}
break;
/* ----- Processing packet, read byte -------------------------------------*/
case READ_BYTE:
switch(token) {
case T_BYTE:
/* Record the byte */
write_byte(str);
break;
case T_TEXT:
case T_DIRECTIVE:
case T_OFFSET:
state = READ_TEXT;
break;
case T_EOL:
state = START_OF_LINE;
break;
case T_EOF:
write_current_packet();
break;
default:
break;
}
break;
/* ----- Processing packet, read text -------------------------------------*/
case READ_TEXT:
switch(token) {
case T_EOL:
state = START_OF_LINE;
break;
case T_EOF:
write_current_packet();
break;
default:
break;
}
break;
default:
fprintf(stderr, "FATAL ERROR: Bad state (%d)", state);
exit(-1);
}
if (debug>=2)
fprintf(stderr, ", %s)\n", state_str[state]);
}
/*----------------------------------------------------------------------
* Import a text file.
*/
int
text_import(const text_import_info_t *info)
{
int ret;
struct tm *now_tm;
packet_buf = (guint8 *)g_malloc(sizeof(HDR_ETHERNET) + sizeof(HDR_IP) +
sizeof(HDR_SCTP) + sizeof(HDR_DATA_CHUNK) +
sizeof(HDR_EXPORT_PDU) + WTAP_MAX_PACKET_SIZE_STANDARD);
if (!packet_buf)
{
fprintf(stderr, "FATAL ERROR: no memory for packet buffer");
exit(-1);
}
/* Lets start from the beginning */
state = INIT;
curr_offset = 0;
packet_start = 0;
packet_preamble_len = 0;
ts_sec = time(0); /* initialize to current time */
now_tm = localtime(&ts_sec);
direction = PACK_FLAGS_DIRECTION_UNKNOWN;
if (now_tm == NULL) {
/*
* This shouldn't happen - on UN*X, this should Just Work, and
* on Windows, it won't work if ts_sec is before the Epoch,
* but it's long after 1970, so....
*/
fprintf(stderr, "localtime(right now) failed\n");
exit(-1);
}
timecode_default = *now_tm;
timecode_default.tm_isdst = -1; /* Unknown for now, depends on time given to the strptime() function */
ts_nsec = 0;
/* Dummy headers */
hdr_ethernet = FALSE;
hdr_ip = FALSE;
hdr_udp = FALSE;
hdr_tcp = FALSE;
hdr_sctp = FALSE;
hdr_data_chunk = FALSE;
hdr_export_pdu = FALSE;
if (info->mode == TEXT_IMPORT_HEXDUMP) {
switch (info->hexdump.offset_type)
{
case OFFSET_NONE:
offset_base = 0;
break;
case OFFSET_HEX:
offset_base = 16;
break;
case OFFSET_OCT:
offset_base = 8;
break;
case OFFSET_DEC:
offset_base = 10;
break;
}
has_direction = info->hexdump.has_direction;
} else if (info->mode == TEXT_IMPORT_REGEX) {
has_direction = g_regex_get_string_number(info->regex.format, "dir") >= 0;
has_seqno = g_regex_get_string_number(info->regex.format, "seqno") >= 0;
}
if (info->timestamp_format)
{
ts_fmt = info->timestamp_format;
}
pcap_link_type = info->encapsulation;
wdh = info->wdh;
switch (info->dummy_header_type)
{
case HEADER_ETH:
hdr_ethernet = TRUE;
hdr_ethernet_proto = info->pid;
break;
case HEADER_IPV4:
hdr_ip = TRUE;
hdr_ip_proto = info->protocol;
hdr_ethernet = TRUE;
hdr_ethernet_proto = 0x800;
break;
case HEADER_UDP:
hdr_udp = TRUE;
hdr_tcp = FALSE;
hdr_src_port = info->src_port;
hdr_dest_port = info->dst_port;
hdr_ip = TRUE;
hdr_ip_proto = 17;
hdr_ethernet = TRUE;
hdr_ethernet_proto = 0x800;
break;
case HEADER_TCP:
hdr_tcp = TRUE;
hdr_udp = FALSE;
hdr_src_port = info->src_port;
hdr_dest_port = info->dst_port;
hdr_ip = TRUE;
hdr_ip_proto = 6;
hdr_ethernet = TRUE;
hdr_ethernet_proto = 0x800;
break;
case HEADER_SCTP:
hdr_sctp = TRUE;
hdr_sctp_src = info->src_port;
hdr_sctp_dest = info->dst_port;
hdr_sctp_tag = info->tag;
hdr_ip = TRUE;
hdr_ip_proto = 132;
hdr_ethernet = TRUE;
hdr_ethernet_proto = 0x800;
break;
case HEADER_SCTP_DATA:
hdr_sctp = TRUE;
hdr_data_chunk = TRUE;
hdr_sctp_src = info->src_port;
hdr_sctp_dest = info->dst_port;
hdr_data_chunk_ppid = info->ppi;
hdr_ip = TRUE;
hdr_ip_proto = 132;
hdr_ethernet = TRUE;
hdr_ethernet_proto = 0x800;
break;
case HEADER_EXPORT_PDU:
hdr_export_pdu = TRUE;
hdr_export_pdu_payload = info->payload;
break;
default:
break;
}
max_offset = info->max_frame_length;
if (info->mode == TEXT_IMPORT_HEXDUMP) {
ret = text_import_scan(info->hexdump.import_text_FILE);
} else if (info->mode == TEXT_IMPORT_REGEX) {
ret = text_import_regex(info);
} else {
ret = -1;
}
g_free(packet_buf);
return ret;
}
/*
* 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:
*/