forked from osmocom/wireshark
ngsniffer: clean up the read process.
Have a routine to read the Sniffer record header, and call that in ngsniffer_read() and ngsniffer_seek_read(). Only call ngsniffer_process_record() for frame records that we understand, so that we only allocate a block for those rather than for records we don't understand or for EOF records, potentially leaking them.
This commit is contained in:
Guy Harris
parent
2c543f999b
commit
dcfa3ec835
|
|
@ -89,6 +89,13 @@ static const char ngsniffer_magic[] = {
|
|||
#define REC_HEADER6 16 /* More broadcast/retransmission counts? */
|
||||
#define REC_HEADER7 17 /* ? */
|
||||
|
||||
/*
|
||||
* Sniffer record header structure.
|
||||
*/
|
||||
struct rec_header {
|
||||
guint16 type; /* record type */
|
||||
guint16 length; /* record length */
|
||||
};
|
||||
|
||||
/*
|
||||
* Sniffer version record format.
|
||||
|
|
@ -501,9 +508,11 @@ static gboolean ngsniffer_read(wtap *wth, wtap_rec *rec, Buffer *buf,
|
|||
int *err, gchar **err_info, gint64 *data_offset);
|
||||
static gboolean ngsniffer_seek_read(wtap *wth, gint64 seek_off,
|
||||
wtap_rec *rec, Buffer *buf, int *err, gchar **err_info);
|
||||
static int ngsniffer_process_record(wtap *wth, gboolean is_random,
|
||||
guint *padding, wtap_rec *rec, Buffer *buf, int *err,
|
||||
gchar **err_info);
|
||||
static gboolean read_rec_header(wtap *wth, gboolean is_random,
|
||||
struct rec_header *hdr, int *err, gchar **err_info);
|
||||
static gboolean ngsniffer_process_record(wtap *wth, gboolean is_random,
|
||||
guint *padding, struct rec_header *hdr, wtap_rec *rec, Buffer *buf,
|
||||
int *err, gchar **err_info);
|
||||
static void set_metadata_frame2(wtap *wth, wtap_rec *rec,
|
||||
struct frame2_rec *frame2);
|
||||
static void set_pseudo_header_frame4(union wtap_pseudo_header *pseudo_header,
|
||||
|
|
@ -1022,7 +1031,7 @@ ngsniffer_read(wtap *wth, wtap_rec *rec, Buffer *buf, int *err,
|
|||
gchar **err_info, gint64 *data_offset)
|
||||
{
|
||||
ngsniffer_t *ngsniffer;
|
||||
int ret;
|
||||
struct rec_header hdr;
|
||||
guint padding;
|
||||
|
||||
ngsniffer = (ngsniffer_t *)wth->priv;
|
||||
|
|
@ -1034,25 +1043,31 @@ ngsniffer_read(wtap *wth, wtap_rec *rec, Buffer *buf, int *err,
|
|||
*data_offset = ngsniffer->seq.uncomp_offset;
|
||||
|
||||
/*
|
||||
* Process the record.
|
||||
* Read the record header.
|
||||
*/
|
||||
ret = ngsniffer_process_record(wth, FALSE, &padding,
|
||||
rec, buf, err, err_info);
|
||||
if (ret < 0) {
|
||||
if (!read_rec_header(wth, FALSE, &hdr, err, err_info)) {
|
||||
/* Read error or short read */
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
* ret is the record type.
|
||||
* Process the record.
|
||||
*/
|
||||
switch (ret) {
|
||||
switch (hdr.type) {
|
||||
|
||||
case REC_FRAME2:
|
||||
case REC_FRAME4:
|
||||
case REC_FRAME6:
|
||||
/*
|
||||
* Packet record.
|
||||
*/
|
||||
if (!ngsniffer_process_record(wth, FALSE, &padding,
|
||||
&hdr, rec, buf, err, err_info)) {
|
||||
/* Read error, short read, or other error */
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
* Skip any extra data in the record.
|
||||
*/
|
||||
if (padding != 0) {
|
||||
|
|
@ -1064,8 +1079,15 @@ ngsniffer_read(wtap *wth, wtap_rec *rec, Buffer *buf, int *err,
|
|||
|
||||
case REC_EOF:
|
||||
/*
|
||||
* End of file. Return an EOF indication.
|
||||
* End of file. Skip past any data (if any),
|
||||
* the length of which is in hdr.length, and
|
||||
* return an EOF indication.
|
||||
*/
|
||||
if (hdr.length != 0) {
|
||||
if (!ng_skip_bytes_seq(wth, hdr.length, err,
|
||||
err_info))
|
||||
return FALSE;
|
||||
}
|
||||
*err = 0; /* EOF, not error */
|
||||
return FALSE;
|
||||
|
||||
|
|
@ -1073,11 +1095,11 @@ ngsniffer_read(wtap *wth, wtap_rec *rec, Buffer *buf, int *err,
|
|||
/*
|
||||
* Well, we don't know what it is, or we know what
|
||||
* it is but can't handle it. Skip past the data
|
||||
* portion, the length of which is in padding,
|
||||
* and keep looping.
|
||||
* portion (if any), the length of which is in
|
||||
* hdr.length, and keep looping.
|
||||
*/
|
||||
if (padding != 0) {
|
||||
if (!ng_skip_bytes_seq(wth, padding, err,
|
||||
if (hdr.length != 0) {
|
||||
if (!ng_skip_bytes_seq(wth, hdr.length, err,
|
||||
err_info))
|
||||
return FALSE;
|
||||
}
|
||||
|
|
@ -1090,31 +1112,36 @@ static gboolean
|
|||
ngsniffer_seek_read(wtap *wth, gint64 seek_off,
|
||||
wtap_rec *rec, Buffer *buf, int *err, gchar **err_info)
|
||||
{
|
||||
int ret;
|
||||
struct rec_header hdr;
|
||||
|
||||
if (!ng_file_seek_rand(wth, seek_off, err, err_info))
|
||||
return FALSE;
|
||||
|
||||
ret = ngsniffer_process_record(wth, TRUE, NULL, rec, buf, err, err_info);
|
||||
if (ret < 0) {
|
||||
if (!read_rec_header(wth, TRUE, &hdr, err, err_info)) {
|
||||
/* Read error or short read */
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
* ret is the record type.
|
||||
* hdr.type is the record type.
|
||||
*/
|
||||
switch (ret) {
|
||||
switch (hdr.type) {
|
||||
|
||||
case REC_FRAME2:
|
||||
case REC_FRAME4:
|
||||
case REC_FRAME6:
|
||||
/* Packet record */
|
||||
if (!ngsniffer_process_record(wth, TRUE, NULL, &hdr, rec, buf,
|
||||
err, err_info)) {
|
||||
/* Read error, short read, or other error */
|
||||
return FALSE;
|
||||
}
|
||||
break;
|
||||
|
||||
default:
|
||||
/*
|
||||
* "Can't happen".
|
||||
* Other record type, or EOF.
|
||||
* This "can't happen".
|
||||
*/
|
||||
ws_assert_not_reached();
|
||||
return FALSE;
|
||||
|
|
@ -1124,18 +1151,57 @@ ngsniffer_seek_read(wtap *wth, gint64 seek_off,
|
|||
}
|
||||
|
||||
/*
|
||||
* Returns -1 on error, REC_EOF on end-of-file, record type on success.
|
||||
* Read the record header.
|
||||
*
|
||||
* Returns TRUE on success, FALSE on error.
|
||||
*/
|
||||
static gboolean
|
||||
read_rec_header(wtap *wth, gboolean is_random, struct rec_header *hdr,
|
||||
int *err, gchar **err_info)
|
||||
{
|
||||
char record_type[2];
|
||||
char record_length[4]; /* only 1st 2 bytes are length */
|
||||
|
||||
/*
|
||||
* Read the record type.
|
||||
*/
|
||||
if (!ng_read_bytes_or_eof(wth, record_type, 2, is_random, err, err_info)) {
|
||||
if (*err != 0)
|
||||
return FALSE;
|
||||
/*
|
||||
* End-of-file; construct a fake EOF record.
|
||||
* (A file might have an EOF record at the end, or
|
||||
* it might just come to an end.)
|
||||
* (XXX - is that true of all Sniffer files?)
|
||||
*/
|
||||
hdr->type = REC_EOF;
|
||||
hdr->length = 0;
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/*
|
||||
* Read the record length.
|
||||
*/
|
||||
if (!ng_read_bytes(wth, record_length, 4, is_random, err, err_info))
|
||||
return FALSE;
|
||||
|
||||
hdr->type = pletoh16(record_type);
|
||||
hdr->length = pletoh16(record_length);
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
/*
|
||||
* Returns TRUE on success, FALSE on error.
|
||||
* If padding is non-null, sets *padding to the amount of padding at
|
||||
* the end of the record.
|
||||
*/
|
||||
static int
|
||||
static gboolean
|
||||
ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
||||
wtap_rec *rec, Buffer *buf, int *err, gchar **err_info)
|
||||
struct rec_header *hdr, wtap_rec *rec, Buffer *buf, int *err,
|
||||
gchar **err_info)
|
||||
{
|
||||
ngsniffer_t *ngsniffer;
|
||||
char record_type[2];
|
||||
char record_length[4]; /* only 1st 2 bytes are length */
|
||||
guint rec_type, rec_length_remaining;
|
||||
guint rec_length_remaining;
|
||||
struct frame2_rec frame2;
|
||||
struct frame4_rec frame4;
|
||||
struct frame6_rec frame6;
|
||||
|
|
@ -1143,26 +1209,15 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
guint8 time_high, time_day;
|
||||
guint64 t, tsecs, tpsecs;
|
||||
|
||||
/*
|
||||
* Read the record header.
|
||||
*/
|
||||
if (!ng_read_bytes_or_eof(wth, record_type, 2, is_random, err, err_info)) {
|
||||
if (*err != 0)
|
||||
return -1;
|
||||
return REC_EOF;
|
||||
}
|
||||
if (!ng_read_bytes(wth, record_length, 4, is_random, err, err_info))
|
||||
return -1;
|
||||
|
||||
rec_type = pletoh16(record_type);
|
||||
rec_length_remaining = pletoh16(record_length);
|
||||
rec_length_remaining = hdr->length;
|
||||
|
||||
/* Initialize - we'll be setting some presence flags below. */
|
||||
rec->presence_flags = 0;
|
||||
rec->rec_type = REC_TYPE_PACKET;
|
||||
rec->block = wtap_block_create(WTAP_BLOCK_PACKET);
|
||||
rec->presence_flags = 0;
|
||||
|
||||
ngsniffer = (ngsniffer_t *)wth->priv;
|
||||
switch (rec_type) {
|
||||
switch (hdr->type) {
|
||||
|
||||
case REC_FRAME2:
|
||||
if (ngsniffer->network == NETWORK_ATM) {
|
||||
|
|
@ -1172,20 +1227,20 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
*/
|
||||
*err = WTAP_ERR_BAD_FILE;
|
||||
*err_info = g_strdup("ngsniffer: REC_FRAME2 record in an ATM Sniffer file");
|
||||
return -1;
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/* Do we have an f_frame2_struct worth of data? */
|
||||
if (rec_length_remaining < sizeof frame2) {
|
||||
*err = WTAP_ERR_BAD_FILE;
|
||||
*err_info = g_strdup("ngsniffer: REC_FRAME2 record length is less than record header length");
|
||||
return -1;
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/* Read the f_frame2_struct */
|
||||
if (!ng_read_bytes(wth, &frame2, (unsigned int)sizeof frame2,
|
||||
is_random, err, err_info))
|
||||
return -1;
|
||||
return FALSE;
|
||||
time_low = pletoh16(&frame2.time_low);
|
||||
time_med = pletoh16(&frame2.time_med);
|
||||
time_high = frame2.time_high;
|
||||
|
|
@ -1206,7 +1261,7 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
*/
|
||||
*err = WTAP_ERR_BAD_FILE;
|
||||
*err_info = g_strdup("ngsniffer: REC_FRAME4 record in a non-ATM Sniffer file");
|
||||
return -1;
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -1223,13 +1278,13 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
if (rec_length_remaining < sizeof frame4) {
|
||||
*err = WTAP_ERR_BAD_FILE;
|
||||
*err_info = g_strdup("ngsniffer: REC_FRAME4 record length is less than record header length");
|
||||
return -1;
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/* Read the f_frame4_struct */
|
||||
if (!ng_read_bytes(wth, &frame4, (unsigned int)sizeof frame4,
|
||||
is_random, err, err_info))
|
||||
return -1;
|
||||
return FALSE;
|
||||
time_low = pletoh16(&frame4.time_low);
|
||||
time_med = pletoh16(&frame4.time_med);
|
||||
time_high = frame4.time_high;
|
||||
|
|
@ -1247,13 +1302,13 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
if (rec_length_remaining < sizeof frame6) {
|
||||
*err = WTAP_ERR_BAD_FILE;
|
||||
*err_info = g_strdup("ngsniffer: REC_FRAME6 record length is less than record header length");
|
||||
return -1;
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/* Read the f_frame6_struct */
|
||||
if (!ng_read_bytes(wth, &frame6, (unsigned int)sizeof frame6,
|
||||
is_random, err, err_info))
|
||||
return -1;
|
||||
return FALSE;
|
||||
time_low = pletoh16(&frame6.time_low);
|
||||
time_med = pletoh16(&frame6.time_med);
|
||||
time_high = frame6.time_high;
|
||||
|
|
@ -1266,26 +1321,12 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
set_pseudo_header_frame6(wth, &rec->rec_header.packet_header.pseudo_header, &frame6);
|
||||
break;
|
||||
|
||||
case REC_EOF:
|
||||
/*
|
||||
* End of file. Return an EOF indication.
|
||||
*/
|
||||
*err = 0; /* EOF, not error */
|
||||
return REC_EOF;
|
||||
|
||||
default:
|
||||
/*
|
||||
* Unknown record type, or type that's not an EOF or
|
||||
* a packet record.
|
||||
* This should never happen.
|
||||
*/
|
||||
if (padding != NULL) {
|
||||
/*
|
||||
* Treat the entire record as padding, so we
|
||||
* skip it.
|
||||
*/
|
||||
*padding = rec_length_remaining;
|
||||
}
|
||||
return rec_type; /* unknown type */
|
||||
ws_assert_not_reached();
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -1300,14 +1341,14 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
*/
|
||||
*err = WTAP_ERR_BAD_FILE;
|
||||
*err_info = g_strdup("ngsniffer: Record length is less than packet size");
|
||||
return -1;
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/*
|
||||
* The maximum value of length is 65535, which is less than
|
||||
* WTAP_MAX_PACKET_SIZE_STANDARD will ever be, so we don't need to check
|
||||
* it.
|
||||
*/
|
||||
|
||||
if (padding != NULL) {
|
||||
/*
|
||||
* Padding, if the frame data size is less than what's
|
||||
|
|
@ -1316,7 +1357,6 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
*padding = rec_length_remaining - size;
|
||||
}
|
||||
|
||||
rec->rec_type = REC_TYPE_PACKET;
|
||||
rec->presence_flags |= true_size ? WTAP_HAS_TS|WTAP_HAS_CAP_LEN : WTAP_HAS_TS;
|
||||
rec->rec_header.packet_header.len = true_size ? true_size : size;
|
||||
rec->rec_header.packet_header.caplen = size;
|
||||
|
|
@ -1327,7 +1367,7 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
ws_buffer_assure_space(buf, size);
|
||||
if (!ng_read_bytes(wth, ws_buffer_start_ptr(buf), size, is_random,
|
||||
err, err_info))
|
||||
return -1;
|
||||
return FALSE;
|
||||
|
||||
rec->rec_header.packet_header.pkt_encap = fix_pseudo_header(wth->file_encap,
|
||||
buf, size, &rec->rec_header.packet_header.pseudo_header);
|
||||
|
|
@ -1363,7 +1403,7 @@ ngsniffer_process_record(wtap *wth, gboolean is_random, guint *padding,
|
|||
rec->ts.secs = (time_t)tsecs;
|
||||
rec->ts.nsecs = (int)(tpsecs/1000); /* psecs to nsecs */
|
||||
|
||||
return rec_type; /* success */
|
||||
return TRUE; /* success */
|
||||
}
|
||||
|
||||
static void
|
||||
|
|
|
|||
Loading…
Reference in New Issue