wireshark/wiretap/k12text.l

604 lines
16 KiB
Plaintext

%top {
/* Include this before everything else, for various large-file definitions */
#include "config.h"
}
/*
* We want a reentrant scanner.
*/
%option reentrant
/*
* We don't use input, so don't generate code for it.
*/
%option noinput
/*
* We don't use unput, so don't generate code for it.
*/
%option nounput
/*
* We don't read interactively from the terminal.
*/
%option never-interactive
/*
* We want to stop processing when we get to the end of the input.
*/
%option noyywrap
/*
* The type for the state we keep for a scanner.
*/
%option extra-type="k12text_state_t *"
/*
* Prefix scanner routines with "k12text_" rather than "yy", so this scanner
* can coexist with other scanners.
*/
%option prefix="k12text_"
%option outfile="k12text.c"
/* Options useful for debugging */
/* noline: Prevent generation of #line directives */
/* Seems to be required when using the */
/* Windows VS debugger so as to be able */
/* to properly step through the code and */
/* set breakpoints & etc using the */
/* k12text.c file rather than the */
/* k12text.l file */
/* XXX: %option noline gives an error message: */
/* "unrecognized %option: line" */
/* with flex 2.5.35; the --noline */
/* command-line option works OK. */
/* */
/* debug: Do output of "rule acceptance" info */
/* during parse */
/* */
/* %option noline */
/* %option debug */
/*
* We have to override the memory allocators so that we don't get
* "unused argument" warnings from the yyscanner argument (which
* we don't use, as we have a global memory allocator).
*
* We provide, as macros, our own versions of the routines generated by Flex,
* which just call malloc()/realloc()/free() (as the Flex versions do),
* discarding the extra argument.
*/
%option noyyalloc
%option noyyrealloc
%option noyyfree
%{
/* k12text.l
*
* Wiretap Library
* Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
/*
* TODO:
* - fix timestamps after midnight
* - verify encapsulations
*/
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <time.h>
#include "wtap-int.h"
#include "wtap.h"
#include "file_wrappers.h"
#include <wsutil/buffer.h>
#include "k12.h"
#ifndef HAVE_UNISTD_H
#define YY_NO_UNISTD_H
#endif
/*
* Disable diagnostics in the code generated by Flex.
*/
DIAG_OFF_FLEX
/*
* State kept by the scanner.
*/
typedef struct {
FILE_T fh;
int err;
gchar *err_info;
int start_state;
guint g_h;
guint g_m;
guint g_s;
guint g_ms;
guint g_ns;
gint g_encap;
guint8 *bb;
guint ii;
gboolean is_k12text;
gboolean at_eof;
guint junk_chars;
gchar* error_str;
guint64 file_bytes_read;
gboolean ok_frame;
} k12text_state_t;
#define KERROR(text) do { yyextra->error_str = g_strdup(text); yyterminate(); } while(0)
#define SET_HOURS(text) yyextra->g_h = (guint) strtoul(text,NULL,10)
#define SET_MINUTES(text) yyextra->g_m = (guint) strtoul(text,NULL,10)
#define SET_SECONDS(text) yyextra->g_s = (guint) strtoul(text,NULL,10)
#define SET_MS(text) yyextra->g_ms = (guint) strtoul(text,NULL,10)
#define SET_NS(text) yyextra->g_ns = (guint) strtoul(text,NULL,10)
#define ADD_BYTE(text) do {if (yyextra->ii >= WTAP_MAX_PACKET_SIZE_STANDARD) {KERROR("frame too large");} yyextra->bb[yyextra->ii++] = (guint8)strtoul(text,NULL,16); } while(0)
#define FINALIZE_FRAME() do { yyextra->ok_frame = TRUE; } while (0)
/*~ #define ECHO*/
#define YY_USER_ACTION yyextra->file_bytes_read += yyleng;
#define YY_USER_INIT { \
k12text_state_t *scanner_state = k12text_get_extra(yyscanner); \
BEGIN(scanner_state->start_state); \
}
#define YY_INPUT(buf,result,max_size) { \
k12text_state_t *scanner_state = k12text_get_extra(yyscanner); \
int c = file_getc(scanner_state->fh); \
if (c == EOF) { \
scanner_state->err = file_error(scanner_state->fh, \
&scanner_state->err_info); \
if (scanner_state->err == 0) \
scanner_state->err = WTAP_ERR_SHORT_READ; \
result = YY_NULL; \
} else { \
buf[0] = c; \
result = 1; \
} \
}
#define MAX_JUNK 400000
#define ECHO
/*
* Private per-file data.
*/
typedef struct {
/*
* The file position after the end of the previous frame processed by
* k12text_read.
*
* We need to keep this around, and seek to it at the beginning of
* each call to k12text_read(), since the lexer undoubtedly did some
* amount of look-ahead when processing the previous frame.
*/
gint64 next_frame_offset;
} k12text_t;
/*
* Sleazy hack to suppress compiler warnings in yy_fatal_error().
*/
#define YY_EXIT_FAILURE ((void)yyscanner, 2)
/*
* Macros for the allocators, to discard the extra argument.
*/
#define k12text_alloc(size, yyscanner) (void *)malloc(size)
#define k12text_realloc(ptr, size, yyscanner) (void *)realloc((char *)(ptr), (size))
#define k12text_free(ptr, yyscanner) free((char *)ptr)
static int k12text_file_type_subtype = -1;
void register_k12text(void);
%}
start_timestamp \053[\055]{9}\053[\055]{15,100}\053[\055]{10,100}\053
oneormoredigits [0-9]+:
twodigits [0-9][0-9]
colon :
comma ,
threedigits [0-9][0-9][0-9]
start_bytes \174\060\040\040\040\174
bytes_junk \174[A-F0-9][A-F0-9\040][A-F0-9\040][A-F0-9\040]\174
byte [a-f0-9][a-f0-9]\174
end_bytes \015?\012\015?\012
eth ETHER
mtp2 MTP-L2
sscop SSCOP
sscfnni SSCF
hdlc HDLC
%START MAGIC NEXT_FRAME HOURS MINUTES M2S SECONDS S2M MS M2N NS ENCAP STARTBYTES BYTE
%%
<MAGIC>{start_timestamp} { yyextra->is_k12text = TRUE; yyterminate(); }
<MAGIC>. { if (++ yyextra->junk_chars > MAX_JUNK) { yyextra->is_k12text = FALSE; yyterminate(); } }
<NEXT_FRAME>{start_timestamp} {BEGIN(HOURS); }
<HOURS>{oneormoredigits} { SET_HOURS(yytext); BEGIN(MINUTES); }
<MINUTES>{twodigits} { SET_MINUTES(yytext); BEGIN(M2S);}
<M2S>{colon} { BEGIN(SECONDS);}
<SECONDS>{twodigits} { SET_SECONDS(yytext); BEGIN(S2M); }
<S2M>{comma} { BEGIN(MS); }
<MS>{threedigits} { SET_MS(yytext); BEGIN(M2N); }
<M2N>{comma} { BEGIN(NS); }
<NS>{threedigits} { SET_NS(yytext); BEGIN(ENCAP);}
<ENCAP>{eth} {yyextra->g_encap = WTAP_ENCAP_ETHERNET; BEGIN(STARTBYTES); }
<ENCAP>{mtp2} {yyextra->g_encap = WTAP_ENCAP_MTP2; BEGIN(STARTBYTES); }
<ENCAP>{sscop} {yyextra->g_encap = WTAP_ENCAP_ATM_PDUS; BEGIN(STARTBYTES); }
<ENCAP>{sscfnni} {yyextra->g_encap = WTAP_ENCAP_MTP3; BEGIN(STARTBYTES); }
<ENCAP>{hdlc} {yyextra->g_encap = WTAP_ENCAP_CHDLC; BEGIN(STARTBYTES); }
<ENCAP,STARTBYTES>{start_bytes} { BEGIN(BYTE); }
<BYTE>{byte} { ADD_BYTE(yytext); }
<BYTE>{bytes_junk} ;
<BYTE>{end_bytes} { FINALIZE_FRAME(); yyterminate(); }
. { if (++yyextra->junk_chars > MAX_JUNK) { KERROR("too much junk"); } }
<<EOF>> { yyextra->at_eof = TRUE; yyterminate(); }
%%
/*
* Turn diagnostics back on, so we check the code that we've written.
*/
DIAG_ON_FLEX
/* Fill in pkthdr */
static gboolean
k12text_set_headers(wtap_rec *rec, k12text_state_t *state,
int *err, gchar **err_info)
{
rec->rec_type = REC_TYPE_PACKET;
rec->block = wtap_block_create(WTAP_BLOCK_PACKET);
rec->presence_flags = WTAP_HAS_TS|WTAP_HAS_CAP_LEN;
rec->ts.secs = 946681200 + (3600*state->g_h) + (60*state->g_m) + state->g_s;
rec->ts.nsecs = 1000000*state->g_ms + 1000*state->g_ns;
rec->rec_header.packet_header.caplen = rec->rec_header.packet_header.len = state->ii;
rec->rec_header.packet_header.pkt_encap = state->g_encap;
/* The file-encap is WTAP_ENCAP_PER_PACKET */
switch(state->g_encap) {
case WTAP_ENCAP_ETHERNET:
rec->rec_header.packet_header.pseudo_header.eth.fcs_len = 0;
break;
case WTAP_ENCAP_MTP3:
case WTAP_ENCAP_CHDLC:
/* no pseudo_header to fill in for these types */
break;
case WTAP_ENCAP_MTP2: /* not (yet) supported */
/* XXX: I don't know how to fill in the */
/* pseudo_header for these types. */
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup("k12text: MTP2 packets not yet supported");
return FALSE;
case WTAP_ENCAP_ATM_PDUS: /* not (yet) supported */
/* XXX: I don't know how to fill in the */
/* pseudo_header for these types. */
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup("k12text: SSCOP packets not yet supported");
return FALSE;
default:
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup("k12text: unknown encapsulation type");
return FALSE;
}
return TRUE;
}
/* Note: k12text_reset is called each time data is to be processed from */
/* a file. This ensures that no "state" from a previous read is */
/* used (such as the lexer look-ahead buffer, file_handle, file */
/* position and so on. This allows a single lexer buffer to be */
/* used even when multiple files are open simultaneously (as for */
/* a file merge). */
static gboolean
k12text_run_scanner(k12text_state_t *state, FILE_T fh, int start_state,
int *err, gchar **err_info)
{
yyscan_t scanner = NULL;
if (yylex_init(&scanner) != 0) {
/* errno is set if this fails */
*err = errno;
*err_info = NULL;
return FALSE;
}
state->fh = fh;
state->err = 0;
state->err_info = NULL;
state->start_state = start_state;
state->g_encap = WTAP_ENCAP_UNKNOWN;
state->ok_frame = FALSE;
state->is_k12text = FALSE;
state->at_eof = FALSE;
state->junk_chars = 0;
state->error_str = NULL;
state->file_bytes_read=0;
state->g_h=0;
state->g_m=0;
state->g_s=0;
state->g_ns=0;
state->g_ms=0;
state->ii=0;
/* Associate the state with the scanner */
k12text_set_extra(state, scanner);
yylex(scanner);
yylex_destroy(scanner);
if (state->err != 0 && state->err != WTAP_ERR_SHORT_READ) {
/* I/O error. */
*err = state->err;
*err_info = state->err_info;
return FALSE;
}
return TRUE;
}
static gboolean
k12text_read(wtap *wth, wtap_rec *rec, Buffer *buf, int *err, char ** err_info, gint64 *data_offset)
{
k12text_t *k12text = (k12text_t *)wth->priv;
k12text_state_t state;
/*
* We seek to the file position after the end of the previous frame
* processed by k12text_read(), since the lexer undoubtedly did some
* amount of look-ahead when processing the previous frame.
*
* We also clear out any lexer state (eg: look-ahead buffer) and
* init vars set by lexer.
*/
if ( file_seek(wth->fh, k12text->next_frame_offset, SEEK_SET, err) == -1) {
return FALSE;
}
state.bb = (guint8*)g_malloc(WTAP_MAX_PACKET_SIZE_STANDARD);
if (!k12text_run_scanner(&state, wth->fh, NEXT_FRAME, err, err_info)) {
g_free(state.bb);
return FALSE;
}
if (state.ok_frame == FALSE) {
if (state.at_eof) {
*err = 0;
*err_info = NULL;
} else {
*err = WTAP_ERR_BAD_FILE;
*err_info = state.error_str;
}
g_free(state.bb);
return FALSE;
}
*data_offset = k12text->next_frame_offset; /* file position for beginning of this frame */
k12text->next_frame_offset += state.file_bytes_read; /* file position after end of this frame */
if (!k12text_set_headers(rec, &state, err, err_info)) {
g_free(state.bb);
return FALSE;
}
ws_buffer_assure_space(buf, rec->rec_header.packet_header.caplen);
memcpy(ws_buffer_start_ptr(buf), state.bb, rec->rec_header.packet_header.caplen);
g_free(state.bb);
return TRUE;
}
static gboolean
k12text_seek_read(wtap *wth, gint64 seek_off, wtap_rec *rec, Buffer *buf, int *err, char **err_info)
{
k12text_state_t state;
if ( file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1) {
return FALSE;
}
state.bb = (guint8*)g_malloc(WTAP_MAX_PACKET_SIZE_STANDARD);
if (!k12text_run_scanner(&state, wth->random_fh, NEXT_FRAME, err, err_info)) {
g_free(state.bb);
return FALSE;
}
if (state.ok_frame == FALSE) {
*err = WTAP_ERR_BAD_FILE;
if (state.at_eof) {
/* What happened ? The desired frame was previously read without a problem */
*err_info = g_strdup("Unexpected EOF (program error ?)");
} else {
*err_info = state.error_str;
}
g_free(state.bb);
return FALSE;
}
if (!k12text_set_headers(rec, &state, err, err_info)) {
g_free(state.bb);
return FALSE;
}
ws_buffer_assure_space(buf, rec->rec_header.packet_header.caplen);
memcpy(ws_buffer_start_ptr(buf), state.bb, rec->rec_header.packet_header.caplen);
g_free(state.bb);
return TRUE;
}
wtap_open_return_val
k12text_open(wtap *wth, int *err, gchar **err_info)
{
k12text_t *k12text;
k12text_state_t state;
state.bb = (guint8*)g_malloc(WTAP_MAX_PACKET_SIZE_STANDARD);
if (!k12text_run_scanner(&state, wth->fh, MAGIC, err, err_info)) {
g_free(state.bb);
return WTAP_OPEN_ERROR;
}
if (!state.is_k12text) {
/* *err might have been set to WTAP_ERR_SHORT_READ */
*err = 0;
g_free(state.bb);
return WTAP_OPEN_NOT_MINE;
}
if ( file_seek(wth->fh, 0, SEEK_SET, err) == -1) {
g_free(state.bb);
return WTAP_OPEN_ERROR;
}
k12text = g_new(k12text_t, 1);
wth->priv = (void *)k12text;
k12text->next_frame_offset = 0;
wth->file_type_subtype = k12text_file_type_subtype;
wth->file_encap = WTAP_ENCAP_PER_PACKET;
wth->snapshot_length = 0;
wth->subtype_read = k12text_read;
wth->subtype_seek_read = k12text_seek_read;
wth->file_tsprec = WTAP_TSPREC_NSEC;
g_free(state.bb);
return WTAP_OPEN_MINE;
}
static const struct { int e; const char* s; } encaps[] = {
{ WTAP_ENCAP_ETHERNET, "ETHER" },
{ WTAP_ENCAP_MTP2, "MTP-L2" },
{ WTAP_ENCAP_ATM_PDUS, "SSCOP" },
{ WTAP_ENCAP_MTP3, "SSCF" },
{ WTAP_ENCAP_CHDLC, "HDLC" },
/* ... */
{ 0, NULL }
};
static gboolean
k12text_dump(wtap_dumper *wdh, const wtap_rec *rec,
const guint8 *pd, int *err, gchar **err_info _U_) {
#define K12BUF_SIZE 196808
char *buf;
size_t left = K12BUF_SIZE;
size_t wl;
char *p;
const char* str_enc;
guint i;
guint ns;
guint ms;
gboolean ret;
struct tm *tmp;
/* Don't write anything bigger than we're willing to read. */
if (rec->rec_header.packet_header.caplen > WTAP_MAX_PACKET_SIZE_STANDARD) {
*err = WTAP_ERR_PACKET_TOO_LARGE;
return FALSE;
}
str_enc = NULL;
for(i=0; encaps[i].s; i++) {
if (rec->rec_header.packet_header.pkt_encap == encaps[i].e) {
str_enc = encaps[i].s;
break;
}
}
if (str_enc == NULL) {
/*
* That encapsulation type is not supported. Fail.
*/
*err = WTAP_ERR_UNWRITABLE_ENCAP;
return FALSE;
}
buf = (char *)g_malloc(K12BUF_SIZE);
p = buf;
ms = rec->ts.nsecs / 1000000;
ns = (rec->ts.nsecs - (1000000*ms))/1000;
tmp = gmtime(&rec->ts.secs);
if (tmp == NULL)
g_snprintf(p, 90, "+---------+---------------+----------+\r\nXX:XX:XX,");
else
strftime(p, 90, "+---------+---------------+----------+\r\n%H:%M:%S,", tmp);
wl = strlen(p);
p += wl;
left -= wl;
wl = g_snprintf(p, (gulong)left, "%.3d,%.3d %s\r\n|0 |", ms, ns, str_enc);
p += wl;
left -= wl;
for(i = 0; i < rec->rec_header.packet_header.caplen && left > 2; i++) {
wl = g_snprintf(p, (gulong)left, "%.2x|", pd[i]);
p += wl;
left -= wl;
}
wl = g_snprintf(p, (gulong)left, "\r\n\r\n");
left -= wl;
ret = wtap_dump_file_write(wdh, buf, K12BUF_SIZE - left, err);
g_free(buf);
return ret;
}
static gboolean
k12text_dump_open(wtap_dumper *wdh, int *err _U_, gchar **err_info _U_)
{
wdh->subtype_write = k12text_dump;
return TRUE;
}
static int
k12text_dump_can_write_encap(int encap)
{
switch (encap) {
case WTAP_ENCAP_PER_PACKET:
case WTAP_ENCAP_ETHERNET:
case WTAP_ENCAP_MTP3:
case WTAP_ENCAP_CHDLC:
return 0;
case WTAP_ENCAP_MTP2:
case WTAP_ENCAP_ATM_PDUS:
default:
return WTAP_ERR_UNWRITABLE_ENCAP;
}
}
static const struct supported_block_type k12text_blocks_supported[] = {
/*
* We support packet blocks, with no comments or other options.
*/
{ WTAP_BLOCK_PACKET, MULTIPLE_BLOCKS_SUPPORTED, NO_OPTIONS_SUPPORTED }
};
static const struct file_type_subtype_info k12text_info = {
"K12 text file", "k12text", "txt", NULL,
FALSE, BLOCKS_SUPPORTED(k12text_blocks_supported),
k12text_dump_can_write_encap, k12text_dump_open, NULL
};
void register_k12text(void)
{
k12text_file_type_subtype = wtap_register_file_type_subtype(&k12text_info);
/*
* Register name for backwards compatibility with the
* wtap_filetypes table in Lua.
*/
wtap_register_backwards_compatibility_lua_name("K12TEXT",
k12text_file_type_subtype);
}