forked from osmocom/wireshark
EPL: wrong size detection of last segment
- fixed size detection of last segment in multiple read/write ASNDs
This commit is contained in:
Christian Krump
Wireshark GitLab Utility
parent
34626f2596
commit
76e56358c2
|
|
@ -4348,6 +4348,7 @@ dissect_epl_sdo_command_write_multiple_by_index(struct epl_convo *convo, proto_t
|
|||
proto_tree *psf_od_tree;
|
||||
struct object *obj = NULL;
|
||||
const struct subobject *subobj = NULL;
|
||||
guint16 segment_restsize = segment_size;
|
||||
|
||||
|
||||
/* Offset is calculated simply by only applying EPL payload offset, not packet offset.
|
||||
|
|
@ -4378,45 +4379,38 @@ dissect_epl_sdo_command_write_multiple_by_index(struct epl_convo *convo, proto_t
|
|||
/* the data is aligned in 4-byte increments, therfore maximum padding is 3 */
|
||||
padding = tvb_get_guint8 ( tvb, offset + 7 ) & 0x03;
|
||||
|
||||
datalength = offsetincrement - ( offset - EPL_SOA_EPLV_OFFSET );
|
||||
/* An offset increment of zero usually indicates, that we are at the end
|
||||
* of the payload. But we cannot ignore the end, because packages are
|
||||
* stacked up until the last byte */
|
||||
if ( offsetincrement == 0 )
|
||||
datalength = remlength - EPL_SOA_EPLV_OFFSET;
|
||||
|
||||
/* Possible guint overflow */
|
||||
if ( ( datalength + EPL_SOA_EPLV_OFFSET ) > remlength )
|
||||
break;
|
||||
|
||||
/* Last frame detected */
|
||||
if ( offsetincrement == 0 )
|
||||
if (offsetincrement == 0)
|
||||
{
|
||||
datalength = remlength;
|
||||
|
||||
/* guarding size against remaining length */
|
||||
if ( remlength < EPL_SOA_EPLV_OFFSET )
|
||||
break;
|
||||
|
||||
size = remlength - EPL_SOA_EPLV_OFFSET - padding;
|
||||
datalength = segment_restsize;
|
||||
lastentry = TRUE;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* Each entry has a header size of 8, based on the following calculation:
|
||||
* - 4 byte for byte position of next data set
|
||||
* - 2 byte for index
|
||||
* - 1 byte for subindex
|
||||
* - 1 byte for reserved and padding */
|
||||
|
||||
/* Guarding against readout of padding. Probability is nearly zero, as
|
||||
* padding was checked above, but to be sure, this remains here */
|
||||
if ( (guint32)( padding + 8 ) >= datalength )
|
||||
break;
|
||||
|
||||
/* size of data is datalength - ( entry header size and padding ) */
|
||||
size = datalength - 8 - padding;
|
||||
datalength = offsetincrement - (offset - EPL_SOA_EPLV_OFFSET);
|
||||
}
|
||||
/* decrease restsize */
|
||||
segment_restsize -= datalength;
|
||||
|
||||
/* Possible guint overflow */
|
||||
if ( datalength > remlength )
|
||||
break;
|
||||
|
||||
/* Each entry has a header size of 8, based on the following calculation:
|
||||
* - 4 byte for byte position of next data set
|
||||
* - 2 byte for index
|
||||
* - 1 byte for subindex
|
||||
* - 1 byte for reserved and padding */
|
||||
|
||||
/* Guarding against readout of padding. Probability is nearly zero, as
|
||||
* padding was checked above, but to be sure, this remains here */
|
||||
if ((guint32)(padding + 8) >= datalength)
|
||||
break;
|
||||
|
||||
/* size of data is datalength - ( entry header size and padding ) */
|
||||
size = datalength - 8 - padding;
|
||||
|
||||
dataoffset = offset + 4;
|
||||
|
||||
|
|
@ -4689,6 +4683,7 @@ dissect_epl_sdo_command_read_multiple_by_index(struct epl_convo *convo, proto_tr
|
|||
struct object *obj = NULL;
|
||||
const struct subobject *subobj = NULL;
|
||||
const char *name;
|
||||
guint16 segment_restsize = segment_size;
|
||||
|
||||
/* Offset is calculated simply by only applying EPL payload offset, not packet offset.
|
||||
* The packet offset is 16, as this is the number of bytes trailing the SDO payload.
|
||||
|
|
@ -4720,45 +4715,38 @@ dissect_epl_sdo_command_read_multiple_by_index(struct epl_convo *convo, proto_tr
|
|||
if ((tvb_get_guint8 ( tvb, offset + 7 ) & 0x80) == 0x80)
|
||||
is_abort = TRUE;
|
||||
|
||||
datalength = offsetincrement - ( offset - EPL_SOA_EPLV_OFFSET );
|
||||
/* An offset increment of zero usually indicates, that we are at the end
|
||||
* of the payload. But we cannot ignore the end, because packages are
|
||||
* stacked up until the last byte */
|
||||
if ( offsetincrement == 0 )
|
||||
datalength = remlength - EPL_SOA_EPLV_OFFSET;
|
||||
|
||||
/* Possible guint overflow */
|
||||
if ( ( datalength + EPL_SOA_EPLV_OFFSET ) > remlength )
|
||||
break;
|
||||
|
||||
/* Last frame detected */
|
||||
if ( offsetincrement == 0 )
|
||||
/* An offset increment of zero usually indicates, that we are at the end
|
||||
* of the payload. But we cannot ignore the end, because packages are
|
||||
* stacked up until the last byte */
|
||||
if (offsetincrement == 0)
|
||||
{
|
||||
datalength = remlength;
|
||||
|
||||
/* guarding size against remaining length */
|
||||
if ( remlength < EPL_SOA_EPLV_OFFSET )
|
||||
break;
|
||||
|
||||
size = remlength - EPL_SOA_EPLV_OFFSET - padding;
|
||||
datalength = segment_restsize;
|
||||
lastentry = TRUE;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* Each entry has a header size of 8, based on the following calculation:
|
||||
* - 4 byte for byte position of next data set
|
||||
* - 2 byte for index
|
||||
* - 1 byte for subindex
|
||||
* - 1 byte for reserved and padding */
|
||||
|
||||
/* Guarding against readout of padding. Probability is nearly zero, as
|
||||
* padding was checked above, but to be sure, this remains here */
|
||||
if ( (guint32)( padding + 8 ) >= datalength )
|
||||
break;
|
||||
|
||||
/* size of data is datalength - ( entry header size and padding ) */
|
||||
size = datalength - 8 - padding;
|
||||
datalength = offsetincrement - (offset - EPL_SOA_EPLV_OFFSET);
|
||||
}
|
||||
/* decrease restsize */
|
||||
segment_restsize -= datalength;
|
||||
|
||||
/* Possible guint overflow */
|
||||
if (datalength > remlength)
|
||||
break;
|
||||
|
||||
/* Each entry has a header size of 8, based on the following calculation:
|
||||
* - 4 byte for byte position of next data set
|
||||
* - 2 byte for index
|
||||
* - 1 byte for subindex
|
||||
* - 1 byte for reserved and padding */
|
||||
|
||||
/* Guarding against readout of padding. Probability is nearly zero, as
|
||||
* padding was checked above, but to be sure, this remains here */
|
||||
if ((guint32)(padding + 8) >= datalength)
|
||||
break;
|
||||
|
||||
/* size of data is datalength - ( entry header size and padding ) */
|
||||
size = datalength - 8 - padding;
|
||||
|
||||
dataoffset = offset + 4;
|
||||
|
||||
|
|
@ -5059,7 +5047,7 @@ dissect_epl_sdo_command_read_multiple_by_index(struct epl_convo *convo, proto_tr
|
|||
static gint
|
||||
dissect_epl_sdo_command_read_by_index(struct epl_convo *convo, proto_tree *epl_tree, tvbuff_t *tvb, packet_info *pinfo, gint offset, guint8 segmented, gboolean response, guint16 segment_size)
|
||||
{
|
||||
gint size, payload_length;
|
||||
gint size, payload_length, rem_size = 0;
|
||||
guint16 idx = 0x00;
|
||||
guint8 subindex = 0x00;
|
||||
guint32 fragmentId, frame;
|
||||
|
|
@ -5213,7 +5201,17 @@ dissect_epl_sdo_command_read_by_index(struct epl_convo *convo, proto_tree *epl_t
|
|||
|
||||
}
|
||||
|
||||
offset = dissect_epl_payload(epl_tree, tvb, pinfo, offset, size, type, EPL_ASND);
|
||||
/* determine remaining SDO payload size (depends on segment size of current command) */
|
||||
if (size > (segment_size - 4))
|
||||
{
|
||||
rem_size = (segment_size - 4);
|
||||
}
|
||||
else
|
||||
{
|
||||
rem_size = size;
|
||||
}
|
||||
|
||||
offset = dissect_epl_payload(epl_tree, tvb, pinfo, offset, rem_size, type, EPL_ASND);
|
||||
}
|
||||
|
||||
return offset;
|
||||
|
|
|
|||
Loading…
Reference in New Issue