aboutsummaryrefslogtreecommitdiffstats
path: root/epan/dissectors/packet-rlc-lte.c
diff options
context:
space:
mode:
Diffstat (limited to 'epan/dissectors/packet-rlc-lte.c')
-rw-r--r--epan/dissectors/packet-rlc-lte.c195
1 files changed, 151 insertions, 44 deletions
diff --git a/epan/dissectors/packet-rlc-lte.c b/epan/dissectors/packet-rlc-lte.c
index 7a06d69832..54d88ffa61 100644
--- a/epan/dissectors/packet-rlc-lte.c
+++ b/epan/dissectors/packet-rlc-lte.c
@@ -118,6 +118,7 @@ static int hf_rlc_lte_context_channel_type = -1;
static int hf_rlc_lte_context_channel_id = -1;
static int hf_rlc_lte_context_pdu_length = -1;
static int hf_rlc_lte_context_um_sn_length = -1;
+static int hf_rlc_lte_context_am_sn_length = -1;
/* Transparent mode fields */
static int hf_rlc_lte_tm = -1;
@@ -148,8 +149,13 @@ static int hf_rlc_lte_am_p = -1;
static int hf_rlc_lte_am_fi = -1;
static int hf_rlc_lte_am_fixed_e = -1;
static int hf_rlc_lte_am_fixed_sn = -1;
+static int hf_rlc_lte_am_fixed_reserved = -1;
+static int hf_rlc_lte_am_segment_lsf16 = -1;
+static int hf_rlc_lte_am_fixed_reserved2 = -1;
+static int hf_rlc_lte_am_fixed_sn16 = -1;
static int hf_rlc_lte_am_segment_lsf = -1;
static int hf_rlc_lte_am_segment_so = -1;
+static int hf_rlc_lte_am_segment_so16 = -1;
static int hf_rlc_lte_am_data = -1;
/* Control fields */
@@ -1204,7 +1210,11 @@ static void addChannelSequenceInfo(sequence_analysis_report *p,
p_rlc_lte_info->channelId);
proto_item_append_text(seqnum_ti, " - SNs missing (%u to %u)",
p->firstSN, p->lastSN);
- tap_info->missingSNs = ((1024 + p->lastSN - p->firstSN) % 1024) + 1;
+ if (p_rlc_lte_info->sequenceNumberLength == AM_SN_LENGTH_16_BITS) {
+ tap_info->missingSNs = ((65536 + (guint32)p->lastSN - (guint32)p->firstSN) % 65536) + 1;
+ } else {
+ tap_info->missingSNs = ((1024 + p->lastSN - p->firstSN) % 1024) + 1;
+ }
}
else {
expert_add_info_format(pinfo, ti, &ei_rlc_lte_am_sn_missing,
@@ -1273,7 +1283,7 @@ static void addChannelSequenceInfo(sequence_analysis_report *p,
if (!p->sequenceExpectedCorrect) {
/* Work out SN wrap (in case needed below) */
guint16 snLimit;
- if (p_rlc_lte_info->UMSequenceNumberLength == 5) {
+ if (p_rlc_lte_info->sequenceNumberLength == UM_SN_LENGTH_5_BITS) {
snLimit = 32;
}
else {
@@ -1400,7 +1410,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
sequence_analysis_report *p_report_in_frame = NULL;
gboolean createdChannel = FALSE;
guint16 expectedSequenceNumber = 0;
- guint16 snLimit = 0;
+ guint32 snLimit = 0;
/* If find stat_report_in_frame already, use that and get out */
if (pinfo->fd->flags.visited) {
@@ -1453,7 +1463,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
switch (p_channel_status->rlcMode) {
case RLC_UM_MODE:
- if (p_rlc_lte_info->UMSequenceNumberLength == 5) {
+ if (p_rlc_lte_info->sequenceNumberLength == UM_SN_LENGTH_5_BITS) {
snLimit = 32;
}
else {
@@ -1563,7 +1573,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
if (p_report_in_frame->previousFrameNum != 0) {
/* Get report for previous frame */
sequence_analysis_report *p_previous_report;
- if (p_rlc_lte_info->UMSequenceNumberLength == 5) {
+ if (p_rlc_lte_info->sequenceNumberLength == UM_SN_LENGTH_5_BITS) {
snLimit = 32;
}
else {
@@ -1588,9 +1598,15 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
case RLC_AM_MODE:
+ if (p_rlc_lte_info->sequenceNumberLength == AM_SN_LENGTH_16_BITS) {
+ snLimit = 65536;
+ } else {
+ snLimit = 1024;
+ }
+
/* Work out expected sequence number */
if (!createdChannel) {
- expectedSequenceNumber = (p_channel_status->previousSequenceNumber + 1) % 1024;
+ expectedSequenceNumber = (p_channel_status->previousSequenceNumber + 1) % snLimit;
}
else {
/* Whatever we got is fine.. */
@@ -1616,7 +1632,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
if (sequenceNumber != expectedSequenceNumber) {
/* Don't trash reassembly info if this looks like a close retx... */
- if (((1024 + sequenceNumber - expectedSequenceNumber) % 1024) < 50) {
+ if (((snLimit + sequenceNumber - expectedSequenceNumber) % snLimit) < 50) {
reassembly_destroy(p_channel_status);
}
}
@@ -1669,7 +1685,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
/* Get report for previous frame */
sequence_analysis_report *p_previous_report;
p_previous_report = (sequence_analysis_report*)g_hash_table_lookup(sequence_analysis_report_hash,
- get_report_hash_key((sequenceNumber+1023) % 1024,
+ get_report_hash_key((sequenceNumber+snLimit-1) % snLimit,
p_report_in_frame->previousFrameNum,
p_rlc_lte_info,
FALSE));
@@ -1683,7 +1699,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
}
/* Previous subframe repeated? */
- else if (((sequenceNumber+1) % 1024) == expectedSequenceNumber) {
+ else if (((sequenceNumber+1) % snLimit) == expectedSequenceNumber) {
p_report_in_frame->state = SN_Repeated;
/* Set report for this frame */
@@ -1702,10 +1718,10 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
else {
/* Need to work out if new (with skips, or likely a retx (due to NACK)) */
- int delta = (1024 + expectedSequenceNumber - sequenceNumber) % 1024;
+ gint delta = (snLimit + expectedSequenceNumber - sequenceNumber) % snLimit;
- /* Rx window is 512, so check to see if this is a retx */
- if (delta < 512) {
+ /* Rx window is 512/32768, so check to see if this is a retx */
+ if (delta < (gint)(snLimit>>1)) {
/* Probably a retx due to receiving NACK */
p_report_in_frame->state = SN_Retx;
@@ -1718,7 +1734,7 @@ static sequence_analysis_state checkChannelSequenceInfo(packet_info *pinfo, tvbu
p_report_in_frame->state = SN_Missing;
p_report_in_frame->firstSN = expectedSequenceNumber;
- p_report_in_frame->lastSN = (1024 + sequenceNumber-1) % 1024;
+ p_report_in_frame->lastSN = (snLimit + sequenceNumber-1) % snLimit;
/* Update channel state - forget about missed SNs */
p_report_in_frame->sequenceExpected = expectedSequenceNumber;
@@ -1915,6 +1931,7 @@ static void checkChannelACKWindow(guint16 ack_sn,
channel_hash_key channel_key;
channel_sequence_analysis_status *p_channel_status;
sequence_analysis_report *p_report_in_frame = NULL;
+ guint32 snLimit;
/* If find stat_report_in_frame already, use that and get out */
if (pinfo->fd->flags.visited) {
@@ -1953,7 +1970,8 @@ static void checkChannelACKWindow(guint16 ack_sn,
/* Is it in the rx window? This test will catch if it's ahead, but we don't
really know what the back of the tx window is... */
- if (((1024 + p_channel_status->previousSequenceNumber+1 - ack_sn) % 1024) > 512) {
+ snLimit = (p_rlc_lte_info->sequenceNumberLength == AM_SN_LENGTH_16_BITS) ? 65536 : 1024;
+ if (((snLimit + (guint32)p_channel_status->previousSequenceNumber+1 - ack_sn) % snLimit) > (snLimit>>1)) {
/* Set result */
p_report_in_frame = wmem_new0(wmem_file_scope(), sequence_analysis_report);
@@ -2087,7 +2105,7 @@ static void dissect_rlc_lte_um(tvbuff_t *tvb, packet_info *pinfo,
/*******************************/
/* Fixed UM header */
- if (p_rlc_lte_info->UMSequenceNumberLength == UM_SN_LENGTH_5_BITS) {
+ if (p_rlc_lte_info->sequenceNumberLength == UM_SN_LENGTH_5_BITS) {
/* Framing info (2 bits) */
proto_tree_add_bits_ret_val(um_header_tree, hf_rlc_lte_um_fi,
tvb, offset*8, 2,
@@ -2104,7 +2122,7 @@ static void dissect_rlc_lte_um(tvbuff_t *tvb, packet_info *pinfo,
&sn, ENC_BIG_ENDIAN);
offset++;
}
- else if (p_rlc_lte_info->UMSequenceNumberLength == UM_SN_LENGTH_10_BITS) {
+ else if (p_rlc_lte_info->sequenceNumberLength == UM_SN_LENGTH_10_BITS) {
guint8 reserved;
proto_item *ti;
@@ -2136,7 +2154,7 @@ static void dissect_rlc_lte_um(tvbuff_t *tvb, packet_info *pinfo,
/* Invalid length of sequence number */
proto_tree_add_expert_format(um_header_tree, pinfo, &ei_rlc_lte_um_sn, tvb, 0, 0,
"Invalid sequence number length (%u bits)",
- p_rlc_lte_info->UMSequenceNumberLength);
+ p_rlc_lte_info->sequenceNumberLength);
return;
}
@@ -2276,9 +2294,10 @@ static void dissect_rlc_lte_am_status_pdu(tvbuff_t *tvb,
rlc_lte_info *p_rlc_lte_info,
rlc_lte_tap_info *tap_info)
{
- guint8 cpt;
+ guint8 cpt, sn_size, so_size;
+ guint32 sn_limit;
guint64 ack_sn, nack_sn;
- guint16 nack_count = 0;
+ guint16 nack_count = 0, so_end_of_pdu;
guint64 e1 = 0, e2 = 0;
guint64 so_start, so_end;
int bit_offset = offset * 8;
@@ -2297,13 +2316,25 @@ static void dissect_rlc_lte_am_status_pdu(tvbuff_t *tvb,
return;
}
+ if (p_rlc_lte_info->sequenceNumberLength == AM_SN_LENGTH_16_BITS) {
+ sn_size = 16;
+ sn_limit = 65536;
+ so_size = 16;
+ so_end_of_pdu = 0xffff;
+ } else {
+ sn_size = 10;
+ sn_limit = 1024;
+ so_size = 15;
+ so_end_of_pdu = 0x7fff;
+ }
+
/* The Status PDU itself starts 4 bits into the byte */
bit_offset += 4;
/* ACK SN */
proto_tree_add_bits_ret_val(tree, hf_rlc_lte_am_ack_sn, tvb,
- bit_offset, 10, &ack_sn, ENC_BIG_ENDIAN);
- bit_offset += 10;
+ bit_offset, sn_size, &ack_sn, ENC_BIG_ENDIAN);
+ bit_offset += sn_size;
write_pdu_label_and_info(top_ti, status_ti, pinfo, " ACK_SN=%-4u", (guint16)ack_sn);
tap_info->ACKNo = (guint16)ack_sn;
@@ -2325,8 +2356,8 @@ static void dissect_rlc_lte_am_status_pdu(tvbuff_t *tvb,
/* NACK_SN */
nack_ti = proto_tree_add_bits_ret_val(tree, hf_rlc_lte_am_nack_sn, tvb,
- bit_offset, 10, &nack_sn, ENC_BIG_ENDIAN);
- bit_offset += 10;
+ bit_offset, sn_size, &nack_sn, ENC_BIG_ENDIAN);
+ bit_offset += sn_size;
write_pdu_label_and_info(top_ti, NULL, pinfo, " NACK_SN=%-4u", (guint16)nack_sn);
/* We shouldn't NACK the ACK_SN! */
@@ -2337,7 +2368,7 @@ static void dissect_rlc_lte_am_status_pdu(tvbuff_t *tvb,
}
/* NACK should always be 'behind' the ACK */
- if ((1024 + ack_sn - nack_sn) % 1024 > 512) {
+ if ((sn_limit + ack_sn - nack_sn) % sn_limit > (sn_limit>>1)) {
expert_add_info(pinfo, nack_ti, &ei_rlc_lte_am_nack_sn_ahead_ack);
}
@@ -2379,15 +2410,15 @@ static void dissect_rlc_lte_am_status_pdu(tvbuff_t *tvb,
if (e2) {
/* Read SOstart, SOend */
proto_tree_add_bits_ret_val(tree, hf_rlc_lte_am_so_start, tvb,
- bit_offset, 15, &so_start, ENC_BIG_ENDIAN);
- bit_offset += 15;
+ bit_offset, so_size, &so_start, ENC_BIG_ENDIAN);
+ bit_offset += so_size;
proto_tree_add_bits_ret_val(tree, hf_rlc_lte_am_so_end, tvb,
- bit_offset, 15, &so_end, ENC_BIG_ENDIAN);
- bit_offset += 15;
+ bit_offset, so_size, &so_end, ENC_BIG_ENDIAN);
+ bit_offset += so_size;
- if ((guint16)so_end == 0x7fff) {
+ if ((guint16)so_end == so_end_of_pdu) {
write_pdu_label_and_info(top_ti, NULL, pinfo,
" (SOstart=%u SOend=<END-OF_PDU>)",
(guint16)so_start);
@@ -2523,9 +2554,33 @@ static void dissect_rlc_lte_am(tvbuff_t *tvb, packet_info *pinfo,
proto_tree_add_item(am_header_tree, hf_rlc_lte_am_fixed_e, tvb, offset, 1, ENC_BIG_ENDIAN);
/* Sequence Number */
- sn = tvb_get_ntohs(tvb, offset) & 0x03ff;
- proto_tree_add_item(am_header_tree, hf_rlc_lte_am_fixed_sn, tvb, offset, 2, ENC_BIG_ENDIAN);
- offset += 2;
+ if (p_rlc_lte_info->sequenceNumberLength == AM_SN_LENGTH_16_BITS) {
+ guint8 reserved;
+
+ if (is_resegmented) {
+ /* Last Segment Field (LSF) */
+ proto_tree_add_item(am_header_tree, hf_rlc_lte_am_segment_lsf16, tvb, offset, 1, ENC_BIG_ENDIAN);
+ /* Reserved (R1) */
+ am_ti = proto_tree_add_item(am_header_tree, hf_rlc_lte_am_fixed_reserved2, tvb, offset, 1, ENC_BIG_ENDIAN);
+ reserved = tvb_get_guint8(tvb, offset) & 0x01;
+ } else {
+ /* Reserved (R1) */
+ am_ti = proto_tree_add_item(am_header_tree, hf_rlc_lte_am_fixed_reserved, tvb, offset, 1, ENC_BIG_ENDIAN);
+ reserved = tvb_get_guint8(tvb, offset) & 0x03;
+ }
+ if (reserved != 0) {
+ expert_add_info_format(pinfo, am_ti, &ei_rlc_lte_reserved_bits_not_zero,
+ "RLC AM Fixed header Reserved bits not zero (found 0x%x)", reserved);
+ }
+ offset += 1;
+ proto_tree_add_item(am_header_tree, hf_rlc_lte_am_fixed_sn16, tvb, offset, 2, ENC_BIG_ENDIAN);
+ sn = tvb_get_ntohs(tvb, offset);
+ offset += 2;
+ } else {
+ proto_tree_add_item(am_header_tree, hf_rlc_lte_am_fixed_sn, tvb, offset, 2, ENC_BIG_ENDIAN);
+ sn = tvb_get_ntohs(tvb, offset) & 0x03ff;
+ offset += 2;
+ }
tap_info->sequenceNumber = sn;
write_pdu_label_and_info(top_ti, am_header_ti, pinfo, "sn=%-4u", sn);
@@ -2535,12 +2590,18 @@ static void dissect_rlc_lte_am(tvbuff_t *tvb, packet_info *pinfo,
if (is_resegmented) {
guint16 segmentOffset;
- /* Last Segment Field (LSF) */
- proto_tree_add_item(am_header_tree, hf_rlc_lte_am_segment_lsf, tvb, offset, 1, ENC_BIG_ENDIAN);
+ if (p_rlc_lte_info->sequenceNumberLength == AM_SN_LENGTH_16_BITS) {
+ /* SO */
+ proto_tree_add_item(am_header_tree, hf_rlc_lte_am_segment_so16, tvb, offset, 2, ENC_BIG_ENDIAN);
+ segmentOffset = tvb_get_ntohs(tvb, offset);
+ } else {
+ /* Last Segment Field (LSF) */
+ proto_tree_add_item(am_header_tree, hf_rlc_lte_am_segment_lsf, tvb, offset, 1, ENC_BIG_ENDIAN);
- /* SO */
- segmentOffset = tvb_get_ntohs(tvb, offset) & 0x7fff;
- proto_tree_add_item(am_header_tree, hf_rlc_lte_am_segment_so, tvb, offset, 2, ENC_BIG_ENDIAN);
+ /* SO */
+ proto_tree_add_item(am_header_tree, hf_rlc_lte_am_segment_so, tvb, offset, 2, ENC_BIG_ENDIAN);
+ segmentOffset = tvb_get_ntohs(tvb, offset) & 0x7fff;
+ }
write_pdu_label_and_info(top_ti, am_header_ti, pinfo, " SO=%u ", segmentOffset);
offset += 2;
}
@@ -2700,7 +2761,7 @@ static gboolean dissect_rlc_lte_heur(tvbuff_t *tvb, packet_info *pinfo,
tvbuff_t *rlc_tvb;
guint8 tag = 0;
gboolean infoAlreadySet = FALSE;
- gboolean umSeqNumLengthTagPresent = FALSE;
+ gboolean seqNumLengthTagPresent = FALSE;
/* Do this again on re-dissection to re-discover offset of actual PDU */
@@ -2734,16 +2795,19 @@ static gboolean dissect_rlc_lte_heur(tvbuff_t *tvb, packet_info *pinfo,
/* Read fixed fields */
p_rlc_lte_info->rlcMode = tvb_get_guint8(tvb, offset++);
+ if (p_rlc_lte_info->rlcMode == RLC_AM_MODE) {
+ p_rlc_lte_info->sequenceNumberLength = AM_SN_LENGTH_10_BITS;
+ }
/* Read optional fields */
while (tag != RLC_LTE_PAYLOAD_TAG) {
/* Process next tag */
tag = tvb_get_guint8(tvb, offset++);
switch (tag) {
- case RLC_LTE_UM_SN_LENGTH_TAG:
- p_rlc_lte_info->UMSequenceNumberLength = tvb_get_guint8(tvb, offset);
+ case RLC_LTE_SN_LENGTH_TAG:
+ p_rlc_lte_info->sequenceNumberLength = tvb_get_guint8(tvb, offset);
offset++;
- umSeqNumLengthTagPresent = TRUE;
+ seqNumLengthTagPresent = TRUE;
break;
case RLC_LTE_DIRECTION_TAG:
p_rlc_lte_info->direction = tvb_get_guint8(tvb, offset);
@@ -2780,7 +2844,7 @@ static gboolean dissect_rlc_lte_heur(tvbuff_t *tvb, packet_info *pinfo,
}
}
- if ((p_rlc_lte_info->rlcMode == RLC_UM_MODE) && (umSeqNumLengthTagPresent == FALSE)) {
+ if ((p_rlc_lte_info->rlcMode == RLC_UM_MODE) && (seqNumLengthTagPresent == FALSE)) {
/* Conditional field is not present */
return FALSE;
}
@@ -2894,7 +2958,14 @@ static void dissect_rlc_lte_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree
if (p_rlc_lte_info->rlcMode == RLC_UM_MODE) {
ti = proto_tree_add_uint(context_tree, hf_rlc_lte_context_um_sn_length,
- tvb, 0, 0, p_rlc_lte_info->UMSequenceNumberLength);
+ tvb, 0, 0, p_rlc_lte_info->sequenceNumberLength);
+ PROTO_ITEM_SET_GENERATED(ti);
+ }
+
+ if (p_rlc_lte_info->rlcMode == RLC_AM_MODE) {
+ ti = proto_tree_add_uint(context_tree, hf_rlc_lte_context_am_sn_length,
+ tvb, 0, 0, p_rlc_lte_info->sequenceNumberLength ?
+ p_rlc_lte_info->sequenceNumberLength : 10);
PROTO_ITEM_SET_GENERATED(ti);
}
@@ -2928,7 +2999,7 @@ static void dissect_rlc_lte_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree
tap_info->channelType = p_rlc_lte_info->channelType;
tap_info->channelId = p_rlc_lte_info->channelId;
tap_info->pduLength = p_rlc_lte_info->pduLength;
- tap_info->UMSequenceNumberLength = p_rlc_lte_info->UMSequenceNumberLength;
+ tap_info->sequenceNumberLength = p_rlc_lte_info->sequenceNumberLength;
tap_info->loggedInMACFrame = (p_get_proto_data(wmem_file_scope(), pinfo, proto_mac_lte, 0) != NULL);
tap_info->rlc_lte_time = pinfo->abs_ts;
@@ -3120,6 +3191,12 @@ void proto_register_rlc_lte(void)
"Length of UM sequence number in bits", HFILL
}
},
+ { &hf_rlc_lte_context_am_sn_length,
+ { "AM Sequence number length",
+ "rlc-lte.am-seqnum-length", FT_UINT8, BASE_DEC, 0, 0x0,
+ "Length of AM sequence number in bits", HFILL
+ }
+ },
/* Transparent mode fields */
{ &hf_rlc_lte_tm,
@@ -3252,6 +3329,30 @@ void proto_register_rlc_lte(void)
"AM Fixed Sequence Number", HFILL
}
},
+ { &hf_rlc_lte_am_fixed_reserved,
+ { "Reserved",
+ "rlc-lte.am.reserved", FT_UINT8, BASE_DEC, 0, 0x03,
+ "Acknowledged Mode Fixed header reserved bits", HFILL
+ }
+ },
+ { &hf_rlc_lte_am_segment_lsf16,
+ { "Last Segment Flag",
+ "rlc-lte.am.segment.lsf", FT_UINT8, BASE_HEX, VALS(lsf_vals), 0x02,
+ NULL, HFILL
+ }
+ },
+ { &hf_rlc_lte_am_fixed_reserved2,
+ { "Reserved",
+ "rlc-lte.am.reserved", FT_UINT8, BASE_DEC, 0, 0x01,
+ "Acknowledged Mode Fixed header reserved bit", HFILL
+ }
+ },
+ { &hf_rlc_lte_am_fixed_sn16,
+ { "Sequence Number",
+ "rlc-lte.am.fixed.sn", FT_UINT16, BASE_DEC, 0, 0xffff,
+ "AM Fixed Sequence Number", HFILL
+ }
+ },
{ &hf_rlc_lte_am_segment_lsf,
{ "Last Segment Flag",
"rlc-lte.am.segment.lsf", FT_UINT8, BASE_HEX, VALS(lsf_vals), 0x80,
@@ -3264,6 +3365,12 @@ void proto_register_rlc_lte(void)
NULL, HFILL
}
},
+ { &hf_rlc_lte_am_segment_so16,
+ { "Segment Offset",
+ "rlc-lte.am.segment.offset", FT_UINT16, BASE_DEC, 0, 0xffff,
+ NULL, HFILL
+ }
+ },
{ &hf_rlc_lte_am_data,
{ "AM Data",
"rlc-lte.am.data", FT_BYTES, BASE_NONE, 0, 0x0,
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-07 18:21:42 +0000