NR: Configure LCID -> RLC Bearer config from RRC

Change-Id: Ida6af4ccd2157f967b9d2340e6f12319e4dbe688
Reviewed-on: https://code.wireshark.org/review/32998
Petri-Dish: Martin Mathieson <martin.r.mathieson@googlemail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Martin Mathieson <martin.r.mathieson@googlemail.com>

7 files changed, 452 insertions, 56 deletions

diff --git a/epan/dissectors/asn1/nr-rrc/nr-rrc.cnf b/epan/dissectors/asn1/nr-rrc/nr-rrc.cnf
index 714efd3971..4ae512adc3 100644
--- a/epan/dissectors/asn1/nr-rrc/nr-rrc.cnf
+++ b/epan/dissectors/asn1/nr-rrc/nr-rrc.cnf
@@ -843,3 +843,93 @@ T-Reselection DISPLAY=BASE_DEC|BASE_UNIT_STRING STRINGS=&units_seconds
 
 #.TYPE_ATTR
 EUTRA-NS-PmaxValue/additionalPmax DISPLAY=BASE_DEC|BASE_UNIT_STRING STRINGS=&units_dbm
+
+
+
+#.FN_BODY RLC-BearerConfig
+  struct mac_nr_info *p_mac_nr_info;
+  /* Get the struct and clear it out */
+  nr_drb_mapping_t *drb_mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  memset(drb_mapping, 0, sizeof(nr_drb_mapping_t));
+%(DEFAULT_BODY)s
+  /* Need UE identifier */
+  p_mac_nr_info = (mac_nr_info *)p_get_proto_data(wmem_file_scope(), actx->pinfo, proto_mac_nr, 0);
+  if (p_mac_nr_info) {
+    drb_mapping->ueid = p_mac_nr_info->ueid;
+    /* Tell MAC about this mapping */
+    set_mac_nr_bearer_mapping(drb_mapping);
+  }
+
+
+#.FN_BODY DRB-Identity VAL_PTR=&value
+  guint32 value;
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+%(DEFAULT_BODY)s
+  mapping->drbid = (guint8)value;
+
+
+#.FN_BODY RLC-Config VAL_PTR=&value
+  guint32 value;
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+%(DEFAULT_BODY)s
+  mapping->rlcMode = (value==0) ? RLC_AM_MODE : RLC_UM_MODE;
+  mapping->rlcMode_present = TRUE;
+
+
+#.FN_BODY LogicalChannelIdentity VAL_PTR=&value
+  guint32 value;
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+%(DEFAULT_BODY)s
+  mapping->lcid = (guint8)value;
+  mapping->lcid_present = TRUE;
+
+
+#.FN_BODY UL-UM-RLC
+%(DEFAULT_BODY)s
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->tempDirection = DIRECTION_UPLINK;
+
+#.FN_BODY DL-UM-RLC
+%(DEFAULT_BODY)s
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->rlcMode_present = TRUE;
+  mapping->rlcMode = RLC_UM_MODE;
+  mapping->tempDirection = DIRECTION_DOWNLINK;
+
+#.FN_BODY UL-AM-RLC
+%(DEFAULT_BODY)s
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->tempDirection = DIRECTION_UPLINK;
+
+#.FN_BODY DL-AM-RLC
+%(DEFAULT_BODY)s
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->tempDirection = DIRECTION_DOWNLINK;
+
+
+#.FN_BODY SN-FieldLengthUM  VAL_PTR=&value
+  guint32 value;
+%(DEFAULT_BODY)s
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  if (mapping->tempDirection == DIRECTION_UPLINK) {
+    mapping->rlcUlSnLength_present = TRUE;
+    mapping->rlcUlSnLength = (value=0) ? 6 : 12;
+  }
+  else {
+    mapping->rlcDlSnLength_present = TRUE;
+    mapping->rlcDlSnLength = (value=0) ? 6 : 12;
+  }
+
+
+#.FN_BODY SN-FieldLengthAM  VAL_PTR=&value
+  guint32 value;
+%(DEFAULT_BODY)s
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  if (mapping->tempDirection == DIRECTION_UPLINK) {
+    mapping->rlcUlSnLength_present = TRUE;
+    mapping->rlcUlSnLength = (value=0) ? 12 : 18;
+  }
+  else {
+    mapping->rlcDlSnLength_present = TRUE;
+    mapping->rlcDlSnLength = (value=0) ? 12 : 18;
+}
diff --git a/epan/dissectors/asn1/nr-rrc/packet-nr-rrc-template.c b/epan/dissectors/asn1/nr-rrc/packet-nr-rrc-template.c
index 9a5113ed03..98c16b170d 100644
--- a/epan/dissectors/asn1/nr-rrc/packet-nr-rrc-template.c
+++ b/epan/dissectors/asn1/nr-rrc/packet-nr-rrc-template.c
@@ -21,12 +21,15 @@
 #include <epan/reassemble.h>
 #include <epan/exceptions.h>
 #include <epan/show_exception.h>
+#include <epan/proto_data.h>
 
 #include <wsutil/str_util.h>
 
 #include "packet-per.h"
 #include "packet-gsm_map.h"
 #include "packet-cell_broadcast.h"
+#include "packet-mac-nr.h"
+#include "packet-rlc-nr.h"
 #include "packet-lte-rrc.h"
 #include "packet-nr-rrc.h"
 
@@ -45,6 +48,8 @@ static wmem_map_t *nr_rrc_etws_cmas_dcs_hash = NULL;
 static reassembly_table nr_rrc_sib7_reassembly_table;
 static reassembly_table nr_rrc_sib8_reassembly_table;
 
+extern int proto_mac_nr;
+
 /* Include constants */
 #include "packet-nr-rrc-val.h"
 
@@ -113,6 +118,7 @@ typedef struct {
   guint16 message_identifier;
   guint8 warning_message_segment_type;
   guint8 warning_message_segment_number;
+  nr_drb_mapping_t drb_mapping;
 } nr_rrc_private_data_t;
 
 /* Helper function to get or create a struct that will be actx->private_data */
@@ -125,6 +131,7 @@ nr_rrc_get_private_data(asn1_ctx_t *actx)
   return (nr_rrc_private_data_t*)actx->private_data;
 }
 
+
 static void
 nr_rrc_call_dissector(dissector_handle_t handle, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
diff --git a/epan/dissectors/packet-catapult-dct2000.c b/epan/dissectors/packet-catapult-dct2000.c
index d04c877fe9..89d4c99a63 100644
--- a/epan/dissectors/packet-catapult-dct2000.c
+++ b/epan/dissectors/packet-catapult-dct2000.c
@@ -29,6 +29,8 @@
 #include "packet-rlc-lte.h"
 #include "packet-pdcp-lte.h"
 
+#include "packet-mac-nr.h"
+
 void proto_reg_handoff_catapult_dct2000(void);
 void proto_register_catapult_dct2000(void);
 
@@ -853,6 +855,7 @@ static void dissect_rrc_lte_nr(tvbuff_t *tvb, gint offset,
     LogicalChannelType  logicalChannelType;
     guint16             cell_id;
     guint8              bcch_transport  = 0;
+    guint32             ueid = 0;
     tvbuff_t           *rrc_tvb;
 
     /* Top-level opcode */
@@ -892,7 +895,7 @@ static void dissect_rrc_lte_nr(tvbuff_t *tvb, gint offset,
             logicalChannelType = Channel_DCCH;
 
             /* UEId */
-            proto_tree_add_item(tree, hf_catapult_dct2000_ueid, tvb, offset, 2, ENC_BIG_ENDIAN);
+            proto_tree_add_item_ret_uint(tree, hf_catapult_dct2000_ueid, tvb, offset, 2, ENC_BIG_ENDIAN, &ueid);
             offset += 2;
 
             /* Get tag of channel type */
@@ -1099,6 +1102,18 @@ static void dissect_rrc_lte_nr(tvbuff_t *tvb, gint offset,
 
     /* Send to RRC dissector, if got here, have sub-dissector and some data left */
     if ((protocol_handle != NULL) && (tvb_reported_length_remaining(tvb, offset) > 0)) {
+
+        /* Set MAC-NR info for this PDU.  Needed so that UEId can be found for this frame,
+         * as used by MAC/RLC/PDCP configuration from RRC dissector */
+        if (ueid) {
+            struct mac_nr_info *p_mac_nr_info;
+            p_mac_nr_info = wmem_new0(wmem_file_scope(), struct mac_nr_info);
+            p_mac_nr_info->ueid = ueid;
+            p_mac_nr_info->direction = (isUplink) ? DIRECTION_UPLINK : DIRECTION_DOWNLINK;
+            /* Store info in packet */
+            set_mac_nr_proto_data(pinfo, p_mac_nr_info);
+        }
+
         rrc_tvb = tvb_new_subset_remaining(tvb, offset);
         call_dissector_only(protocol_handle, rrc_tvb, pinfo, tree, NULL);
     }
diff --git a/epan/dissectors/packet-mac-lte.c b/epan/dissectors/packet-mac-lte.c
index 5f6fde3140..75cef3c50f 100644
--- a/epan/dissectors/packet-mac-lte.c
+++ b/epan/dissectors/packet-mac-lte.c
@@ -4318,7 +4318,7 @@ static void lookup_rlc_channel_from_lcid(guint16 ueid,
         }
     }
     else {
-        /* Look up the mappings for this UE */
+        /* Look up the dynamic mappings for this UE */
         ue_dynamic_drb_mappings_t *ue_mappings = (ue_dynamic_drb_mappings_t *)g_hash_table_lookup(mac_lte_ue_channels_hash, GUINT_TO_POINTER((guint)ueid));
         if (!ue_mappings) {
             return;
diff --git a/epan/dissectors/packet-mac-nr.c b/epan/dissectors/packet-mac-nr.c
index 23b566d0c2..1d612d1d2c 100644
--- a/epan/dissectors/packet-mac-nr.c
+++ b/epan/dissectors/packet-mac-nr.c
@@ -351,6 +351,13 @@ static gint     global_mac_nr_layer_to_show = (gint)ShowRLCLayer;
 /***********************************************************************/
 /* How to dissect lcid 3-32 (presume drb logical channels)             */
 
+/* Where to take LCID -> DRB mappings from */
+enum lcid_drb_source {
+    FromStaticTable, FromConfigurationProtocol
+};
+static gint global_mac_nr_lcid_drb_source = (gint)FromStaticTable;
+
+
 static const value_string drb_lcid_vals[] = {
     { 3,  "LCID 3"},
     { 4,  "LCID 4"},
@@ -409,7 +416,8 @@ static const value_string rlc_bearer_type_vals[] = {
 typedef struct lcid_drb_mapping_t {
     guint32           lcid;
     guint32           drbid;
-    rlc_bearer_type_t bearer_type;
+    rlc_bearer_type_t bearer_type_ul;
+    rlc_bearer_type_t bearer_type_dl;
 } lcid_drb_mapping_t;
 
 /* Mapping entity */
@@ -418,11 +426,32 @@ static guint num_lcid_drb_mappings = 0;
 
 UAT_VS_DEF(lcid_drb_mappings, lcid, lcid_drb_mapping_t, guint8, 3, "LCID 3")
 UAT_DEC_CB_DEF(lcid_drb_mappings, drbid, lcid_drb_mapping_t)
-UAT_VS_DEF(lcid_drb_mappings, bearer_type, lcid_drb_mapping_t, rlc_bearer_type_t, rlcAM12, "AM")
+UAT_VS_DEF(lcid_drb_mappings, bearer_type_ul, lcid_drb_mapping_t, rlc_bearer_type_t, rlcAM12, "AM")
+UAT_VS_DEF(lcid_drb_mappings, bearer_type_dl, lcid_drb_mapping_t, rlc_bearer_type_t, rlcAM12, "AM")
 
 /* UAT object */
 static uat_t* lcid_drb_mappings_uat;
 
+/* Dynamic mappings (set by configuration protocol)
+   LCID is the index into the array of these */
+typedef struct dynamic_lcid_drb_mapping_t {
+    gboolean valid;
+    gint     drbid;
+    rlc_bearer_type_t bearer_type_ul;
+    rlc_bearer_type_t bearer_type_dl;
+    guint8   ul_priority;  // N.B. not yet in rlc_nr_info
+} dynamic_lcid_drb_mapping_t;
+
+typedef struct ue_dynamic_drb_mappings_t {
+    dynamic_lcid_drb_mapping_t mapping[33];  /* Index is LCID (2-32) */
+    guint8 drb_to_lcid_mappings[33];         /* Also map drbid (1-32) -> lcid */
+} ue_dynamic_drb_mappings_t;
+
+static GHashTable *mac_nr_ue_bearers_hash = NULL;
+
+
+
+
 /* When showing RLC info, count PDUs so can append info column properly */
 static guint8   s_number_of_rlc_pdus_shown = 0;
 
@@ -776,7 +805,7 @@ static const value_string buffer_size_8bits_vals[] =
     { 96,  "3934 < BS <= 4189"},
     { 97,  "4189 < BS <= 4461"},
     { 98,  "4461 < BS <= 4751"},
-    { 99, "4751 < BS <= 5059"},
+    { 99,  "4751 < BS <= 5059"},
     { 100, "5059 < BS <= 5387"},
     { 101, "5387 < BS <= 5737"},
     { 102, "5737 < BS <= 6109"},
@@ -1374,59 +1403,80 @@ static proto_item* dissect_me_phr_ph(tvbuff_t *tvb, packet_info *pinfo _U_, prot
 }
 
 
-static void set_rlc_seqnum_length(rlc_bearer_type_t rlc_bearer_type,
-                                  guint8 direction _U_,
-                                  guint8 *seqnum_length)
+static guint8 get_rlc_seqnum_length(rlc_bearer_type_t rlc_bearer_type)
 {
     switch (rlc_bearer_type) {
         case rlcUM6:
-            *seqnum_length = 6;
-            break;
+            return 6;
         case rlcUM12:
-            *seqnum_length = 12;
-            break;
-
+            return 12;
         case rlcAM12:
-            *seqnum_length = 12;
-            break;
+            return 12;
         case rlcAM18:
-            *seqnum_length = 18;
-            break;
+            return 18;
 
         default:
-            break;
+            /* Not expected */
+            return 0;
     }
 }
 
 
 
-/* Lookup channel details for lcid */
-static void lookup_rlc_channel_from_lcid(guint16 ueid _U_,
-                                         guint8 lcid,
-                                         guint8 direction,
-                                         rlc_bearer_type_t *rlc_bearer_type,
-                                         guint8 *seqnum_length,
-                                         gint *drb_id)
+/* Lookup bearer details for lcid */
+static gboolean lookup_rlc_bearer_from_lcid(guint16 ueid,
+                                            guint8 lcid,
+                                            guint8 direction,
+                                            rlc_bearer_type_t *rlc_bearer_type,  /* out */
+                                            guint8 *seqnum_length,               /* out */
+                                            gint *drb_id)                        /* out */
 {
     /* Zero params (in case no match is found) */
     *rlc_bearer_type = rlcRaw;
     *seqnum_length    = 0;
     *drb_id           = 0;
 
-    /* Look up in static (UAT) table */
-    guint m;
-    for (m=0; m < num_lcid_drb_mappings; m++) {
-        if (lcid == lcid_drb_mappings[m].lcid) {
+    if (global_mac_nr_lcid_drb_source == (int)FromStaticTable) {
 
-            *rlc_bearer_type = lcid_drb_mappings[m].bearer_type;
+        /* Look up in static (UAT) table */
+        guint m;
+        for (m=0; m < num_lcid_drb_mappings; m++) {
+            if (lcid == lcid_drb_mappings[m].lcid) {
 
-            /* Set seqnum_length and rlc_ext_li_field */
-            set_rlc_seqnum_length(*rlc_bearer_type, direction, seqnum_length);
+                /* Found, set out parameters */
+                if (direction == DIRECTION_UPLINK) {
+                    *rlc_bearer_type = lcid_drb_mappings[m].bearer_type_ul;
+                }
+                else {
+                    *rlc_bearer_type = lcid_drb_mappings[m].bearer_type_dl;
+                }
+                *seqnum_length = get_rlc_seqnum_length(*rlc_bearer_type);
+                *drb_id = lcid_drb_mappings[m].drbid;
+                return TRUE;
+            }
+        }
+        return FALSE;
+    }
+    else {
+        /* Look up the dynamic mappings for this UE */
+        ue_dynamic_drb_mappings_t *ue_mappings = (ue_dynamic_drb_mappings_t *)g_hash_table_lookup(mac_nr_ue_bearers_hash, GUINT_TO_POINTER((guint)ueid));
+        if (!ue_mappings) {
+            return FALSE;
+        }
 
-            /* Set drb_id */
-            *drb_id = lcid_drb_mappings[m].drbid;
-            break;
+        /* Look up setting gleaned from configuration protocol */
+        if (!ue_mappings->mapping[lcid].valid) {
+            return FALSE;
         }
+
+        /* Found, set out params */
+        *rlc_bearer_type = (direction == DIRECTION_DOWNLINK) ?
+                           ue_mappings->mapping[lcid].bearer_type_ul :
+                           ue_mappings->mapping[lcid].bearer_type_dl;
+        *seqnum_length = get_rlc_seqnum_length(*rlc_bearer_type);
+        *drb_id = ue_mappings->mapping[lcid].drbid;
+
+        return TRUE;
     }
 }
 
@@ -1596,7 +1646,7 @@ static void dissect_ulsch_or_dlsch(tvbuff_t *tvb, packet_info *pinfo, proto_tree
             }
 
             /* Call RLC if configured to do so for this SDU */
-            if ((lcid >= 3) && (lcid <= 32)) {
+            if ((lcid >= 4) && (lcid <= 32)) {
                 /* Look for mapping for this LCID to drb channel set by UAT table */
                 rlc_bearer_type_t rlc_bearer_type;
                 guint8 seqnum_length;
@@ -1604,12 +1654,12 @@ static void dissect_ulsch_or_dlsch(tvbuff_t *tvb, packet_info *pinfo, proto_tree
 
                 // TODO: priority not set.
                 guint8 priority = 0;
-                lookup_rlc_channel_from_lcid(p_mac_nr_info->ueid,
-                                             lcid,
-                                             p_mac_nr_info->direction,
-                                             &rlc_bearer_type,
-                                             &seqnum_length,
-                                             &drb_id);
+                lookup_rlc_bearer_from_lcid(p_mac_nr_info->ueid,
+                                            lcid,
+                                            p_mac_nr_info->direction,
+                                            &rlc_bearer_type,
+                                            &seqnum_length,
+                                            &drb_id);
 
                 /* Dissect according to channel type */
                 switch (rlc_bearer_type) {
@@ -2628,11 +2678,105 @@ static void* lcid_drb_mapping_copy_cb(void* dest, const void* orig, size_t len _
     /* Copy all items over */
     d->lcid  = o->lcid;
     d->drbid = o->drbid;
-    d->bearer_type = o->bearer_type;
+    d->bearer_type_ul = o->bearer_type_ul;
+    d->bearer_type_dl = o->bearer_type_dl;
 
     return d;
 }
 
+static void set_bearer_type(dynamic_lcid_drb_mapping_t *mapping, guint8 rlcMode, guint8 rlcSnLength, guint8 direction)
+{
+    rlc_bearer_type_t *type_var = (direction == DIRECTION_UPLINK) ?
+                                   &mapping->bearer_type_ul :
+                                   &mapping->bearer_type_dl;
+
+    switch (rlcMode) {
+        case RLC_AM_MODE:
+            switch (rlcSnLength) {
+                case 12:
+                    *type_var = rlcAM12;
+                    break;
+                case 18:
+                    *type_var = rlcAM18;
+                    break;
+
+                default:
+                    break;
+            }
+            break;
+        case RLC_UM_MODE:
+            switch (rlcSnLength) {
+                case 6:
+                    *type_var = rlcUM6;
+                    break;
+                case 12:
+                    *type_var = rlcUM12;
+                    break;
+
+                default:
+                    break;
+            }
+            break;
+
+        default:
+            break;
+    }
+}
+
+
+/* Set LCID -> RLC channel mappings from signalling protocol (i.e. RRC or similar). */
+void set_mac_nr_bearer_mapping(nr_drb_mapping_t *drb_mapping)
+{
+    ue_dynamic_drb_mappings_t *ue_mappings;
+    guint8 lcid = 0;
+
+    /* Check lcid range */
+    if (drb_mapping->lcid_present) {
+        lcid = drb_mapping->lcid;
+
+        /* Ignore if LCID is out of range */
+        if ((lcid < 4) || (lcid > 32)) {
+            return;
+        }
+    }
+
+    /* Look for existing UE entry */
+    ue_mappings = (ue_dynamic_drb_mappings_t *)g_hash_table_lookup(mac_nr_ue_bearers_hash,
+                                                                   GUINT_TO_POINTER((guint)drb_mapping->ueid));
+    if (!ue_mappings) {
+        /* If not found, create & add to table */
+        ue_mappings = wmem_new0(wmem_file_scope(), ue_dynamic_drb_mappings_t);
+        g_hash_table_insert(mac_nr_ue_bearers_hash,
+                            GUINT_TO_POINTER((guint)drb_mapping->ueid),
+                            ue_mappings);
+    }
+
+    /* If lcid wasn't supplied, need to try to look up from drbid */
+    if ((lcid == 0) && (drb_mapping->drbid <= 32)) {
+        lcid = ue_mappings->drb_to_lcid_mappings[drb_mapping->drbid];
+    }
+    if (lcid == 0) {
+        /* Still no lcid - give up */
+        return;
+    }
+
+    /* Set array entry */
+    ue_mappings->mapping[lcid].valid = TRUE;
+    ue_mappings->mapping[lcid].drbid = drb_mapping->drbid;
+    ue_mappings->drb_to_lcid_mappings[drb_mapping->drbid] = lcid;
+
+    /* Fill in available RLC info */
+    if (drb_mapping->rlcMode_present) {
+        if (drb_mapping->rlcUlSnLength_present) {
+            set_bearer_type(&ue_mappings->mapping[lcid], drb_mapping->rlcMode, drb_mapping->rlcUlSnLength, DIRECTION_UPLINK);
+        }
+        if (drb_mapping->rlcDlSnLength_present) {
+            set_bearer_type(&ue_mappings->mapping[lcid], drb_mapping->rlcMode, drb_mapping->rlcDlSnLength, DIRECTION_DOWNLINK);
+        }
+    }
+}
+
+
 /* Function to be called from outside this module (e.g. in a plugin) to get per-packet data */
 mac_nr_info *get_mac_nr_proto_data(packet_info *pinfo)
 {
@@ -2645,6 +2789,20 @@ void set_mac_nr_proto_data(packet_info *pinfo, mac_nr_info *p_mac_nr_info)
     p_add_proto_data(wmem_file_scope(), pinfo, proto_mac_nr, 0, p_mac_nr_info);
 }
 
+/* Initializes the hash tables each time a new
+ * file is loaded or re-loaded in wireshark */
+static void mac_nr_init_protocol(void)
+{
+    mac_nr_ue_bearers_hash = g_hash_table_new(g_direct_hash, g_direct_equal);
+}
+
+static void mac_nr_cleanup_protocol(void)
+{
+    g_hash_table_destroy(mac_nr_ue_bearers_hash);
+}
+
+
+
 void proto_register_mac_nr(void)
 {
     static hf_register_info hf[] =
@@ -4280,10 +4438,17 @@ void proto_register_mac_nr(void)
     module_t *mac_nr_module;
     expert_module_t* expert_mac_nr;
 
+    static const enum_val_t lcid_drb_source_vals[] = {
+        {"from-static-stable",          "From static table",           FromStaticTable},
+        {"from-configuration-protocol", "From configuration protocol", FromConfigurationProtocol},
+        {NULL, NULL, -1}
+    };
+
     static uat_field_t lcid_drb_mapping_flds[] = {
         UAT_FLD_VS(lcid_drb_mappings, lcid, "LCID (3-32)", drb_lcid_vals, "The MAC LCID"),
         UAT_FLD_DEC(lcid_drb_mappings, drbid,"DRBID id (1-32)", "Identifier of logical data channel"),
-        UAT_FLD_VS(lcid_drb_mappings, bearer_type, "RLC Channel Type", rlc_bearer_type_vals, "The MAC LCID"),
+        UAT_FLD_VS(lcid_drb_mappings, bearer_type_ul, "UL RLC Bearer Type", rlc_bearer_type_vals, "UL Bearer Mode"),
+        UAT_FLD_VS(lcid_drb_mappings, bearer_type_dl, "DL RLC Bearer Type", rlc_bearer_type_vals, "DL Bearer Mode"),
         UAT_END_FIELDS
     };
 
@@ -4305,6 +4470,12 @@ void proto_register_mac_nr(void)
         "Attempt to decode BCCH, PCCH and CCCH data using NR RRC dissector",
         &global_mac_nr_attempt_rrc_decode);
 
+    prefs_register_enum_preference(mac_nr_module, "lcid_to_drb_mapping_source",
+        "Source of LCID -> drb channel settings",
+        "Set whether LCID -> drb Table is taken from static table (below) or from "
+        "info learned from control protocol (i.e. RRC)",
+        &global_mac_nr_lcid_drb_source, lcid_drb_source_vals, FALSE);
+
     lcid_drb_mappings_uat = uat_new("Static LCID -> drb Table",
                                     sizeof(lcid_drb_mapping_t),
                                     "drb_bearerconfig",
@@ -4325,6 +4496,9 @@ void proto_register_mac_nr(void)
                                   "LCID -> DRB Mappings Table",
                                   "A table that maps from configurable lcids -> RLC bearer configs",
                                   lcid_drb_mappings_uat);
+
+    register_init_routine(&mac_nr_init_protocol);
+    register_cleanup_routine(&mac_nr_cleanup_protocol);
 }
 
 void proto_reg_handoff_mac_nr(void)
diff --git a/epan/dissectors/packet-mac-nr.h b/epan/dissectors/packet-mac-nr.h
index 921a6b22ac..6d3f925fb8 100644
--- a/epan/dissectors/packet-mac-nr.h
+++ b/epan/dissectors/packet-mac-nr.h
@@ -108,6 +108,32 @@ void set_mac_nr_proto_data(packet_info *pinfo, mac_nr_info *p_mac_nr_info);
    continues until the end of the frame) */
 #define MAC_NR_PAYLOAD_TAG         0x01
 
+
+/* Type to store parameters for configuring LCID->RLC channel settings for DRB */
+/* Some are optional, and may not be seen (e.g. on reestablishment) */
+typedef struct nr_drb_mapping_t
+{
+    guint16    ueid;                /* Mandatory */
+    guint8     drbid;               /* Mandatory */
+    gboolean   lcid_present;
+    guint8     lcid;                /* Part of LogicalChannelConfig - optional */
+    gboolean   rlcMode_present;
+    guint8     rlcMode;             /* Part of RLC config - optional */
+
+    guint8     tempDirection;       /* So know direction of next SN length... */
+
+    gboolean   rlcUlSnLength_present;
+    guint8     rlcUlSnLength;        /* Part of RLC config - optional */
+    gboolean   rlcDlSnLength_present;
+    guint8     rlcDlSnLength;        /* Part of RLC config - optional */
+} nr_drb_mapping_t;
+
+
+/* Set details of an LCID -> drb channel mapping.  To be called from
+   configuration protocol (i.e. RRC) */
+void set_mac_nr_bearer_mapping(nr_drb_mapping_t *drb_mapping);
+
+
 /*
  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
  *
diff --git a/epan/dissectors/packet-nr-rrc.c b/epan/dissectors/packet-nr-rrc.c
index 32665e0460..29d49e449d 100644
--- a/epan/dissectors/packet-nr-rrc.c
+++ b/epan/dissectors/packet-nr-rrc.c
@@ -29,12 +29,15 @@
 #include <epan/reassemble.h>
 #include <epan/exceptions.h>
 #include <epan/show_exception.h>
+#include <epan/proto_data.h>
 
 #include <wsutil/str_util.h>
 
 #include "packet-per.h"
 #include "packet-gsm_map.h"
 #include "packet-cell_broadcast.h"
+#include "packet-mac-nr.h"
+#include "packet-rlc-nr.h"
 #include "packet-lte-rrc.h"
 #include "packet-nr-rrc.h"
 
@@ -53,6 +56,8 @@ static wmem_map_t *nr_rrc_etws_cmas_dcs_hash = NULL;
 static reassembly_table nr_rrc_sib7_reassembly_table;
 static reassembly_table nr_rrc_sib8_reassembly_table;
 
+extern int proto_mac_nr;
+
 /* Include constants */
 
 /*--- Included file: packet-nr-rrc-val.h ---*/
@@ -239,7 +244,7 @@ typedef enum _T_targetRAT_Type_enum {
 } T_targetRAT_Type_enum;
 
 /*--- End of included file: packet-nr-rrc-val.h ---*/
-#line 50 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 55 "./asn1/nr-rrc/packet-nr-rrc-template.c"
 
 /* Initialize the protocol and registered fields */
 static int proto_nr_rrc = -1;
@@ -3083,7 +3088,7 @@ static int hf_nr_rrc_overheatingIndicationProhibitTimer = -1;  /* T_overheatingI
 static int dummy_hf_nr_rrc_eag_field = -1; /* never registered */
 
 /*--- End of included file: packet-nr-rrc-hf.c ---*/
-#line 54 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 59 "./asn1/nr-rrc/packet-nr-rrc-template.c"
 static int hf_nr_rrc_serialNumber_gs = -1;
 static int hf_nr_rrc_serialNumber_msg_code = -1;
 static int hf_nr_rrc_serialNumber_upd_nb = -1;
@@ -4286,7 +4291,7 @@ static gint ett_nr_rrc_T_overheatingAssistanceConfig = -1;
 static gint ett_nr_rrc_OverheatingAssistanceConfig = -1;
 
 /*--- End of included file: packet-nr-rrc-ett.c ---*/
-#line 90 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 95 "./asn1/nr-rrc/packet-nr-rrc-template.c"
 static gint ett_nr_rrc_DedicatedNAS_Message = -1;
 static gint ett_rr_rrc_targetRAT_MessageContainer = -1;
 static gint ett_nr_rrc_nas_Container = -1;
@@ -4313,6 +4318,7 @@ typedef struct {
   guint16 message_identifier;
   guint8 warning_message_segment_type;
   guint8 warning_message_segment_number;
+  nr_drb_mapping_t drb_mapping;
 } nr_rrc_private_data_t;
 
 /* Helper function to get or create a struct that will be actx->private_data */
@@ -4325,6 +4331,7 @@ nr_rrc_get_private_data(asn1_ctx_t *actx)
   return (nr_rrc_private_data_t*)actx->private_data;
 }
 
+
 static void
 nr_rrc_call_dissector(dissector_handle_t handle, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
@@ -13877,8 +13884,15 @@ dissect_nr_rrc_CellGroupId(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _
 
 static int
 dissect_nr_rrc_LogicalChannelIdentity(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  guint32 value;
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
-                                                            1U, maxLC_ID, NULL, FALSE);
+                                                            1U, maxLC_ID, &value, FALSE);
+
+  mapping->lcid = (guint8)value;
+  mapping->lcid_present = TRUE;
+
+
 
   return offset;
 }
@@ -14244,8 +14258,14 @@ dissect_nr_rrc_T_cnAssociation(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *ac
 
 static int
 dissect_nr_rrc_DRB_Identity(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  guint32 value;
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
-                                                            1U, 32U, NULL, FALSE);
+                                                            1U, 32U, &value, FALSE);
+
+  mapping->drbid = (guint8)value;
+
+
 
   return offset;
 }
@@ -26400,8 +26420,19 @@ static const value_string nr_rrc_SN_FieldLengthAM_vals[] = {
 
 static int
 dissect_nr_rrc_SN_FieldLengthAM(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  guint32 value;
   offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
-                                     2, NULL, FALSE, 0, NULL);
+                                     2, &value, FALSE, 0, NULL);
+
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  if (mapping->tempDirection == DIRECTION_UPLINK) {
+    mapping->rlcUlSnLength_present = TRUE;
+    mapping->rlcUlSnLength = (value=0) ? 12 : 18;
+  }
+  else {
+    mapping->rlcDlSnLength_present = TRUE;
+    mapping->rlcDlSnLength = (value=0) ? 12 : 18;
+}
 
   return offset;
 }
@@ -26651,6 +26682,10 @@ dissect_nr_rrc_UL_AM_RLC(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_nr_rrc_UL_AM_RLC, UL_AM_RLC_sequence);
 
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->tempDirection = DIRECTION_UPLINK;
+
+
   return offset;
 }
 
@@ -26795,6 +26830,11 @@ dissect_nr_rrc_DL_AM_RLC(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_nr_rrc_DL_AM_RLC, DL_AM_RLC_sequence);
 
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->tempDirection = DIRECTION_DOWNLINK;
+
+
+
   return offset;
 }
 
@@ -26823,8 +26863,21 @@ static const value_string nr_rrc_SN_FieldLengthUM_vals[] = {
 
 static int
 dissect_nr_rrc_SN_FieldLengthUM(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  guint32 value;
   offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
-                                     2, NULL, FALSE, 0, NULL);
+                                     2, &value, FALSE, 0, NULL);
+
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  if (mapping->tempDirection == DIRECTION_UPLINK) {
+    mapping->rlcUlSnLength_present = TRUE;
+    mapping->rlcUlSnLength = (value=0) ? 6 : 12;
+  }
+  else {
+    mapping->rlcDlSnLength_present = TRUE;
+    mapping->rlcDlSnLength = (value=0) ? 6 : 12;
+  }
+
+
 
   return offset;
 }
@@ -26840,6 +26893,10 @@ dissect_nr_rrc_UL_UM_RLC(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_nr_rrc_UL_UM_RLC, UL_UM_RLC_sequence);
 
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->tempDirection = DIRECTION_UPLINK;
+
+
   return offset;
 }
 
@@ -26855,6 +26912,12 @@ dissect_nr_rrc_DL_UM_RLC(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_nr_rrc_DL_UM_RLC, DL_UM_RLC_sequence);
 
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  mapping->rlcMode_present = TRUE;
+  mapping->rlcMode = RLC_UM_MODE;
+  mapping->tempDirection = DIRECTION_DOWNLINK;
+
+
   return offset;
 }
 
@@ -26920,9 +26983,16 @@ static const per_choice_t RLC_Config_choice[] = {
 
 static int
 dissect_nr_rrc_RLC_Config(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  guint32 value;
+  nr_drb_mapping_t *mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
   offset = dissect_per_choice(tvb, offset, actx, tree, hf_index,
                                  ett_nr_rrc_RLC_Config, RLC_Config_choice,
-                                 NULL);
+                                 &value);
+
+  mapping->rlcMode = (value==0) ? RLC_AM_MODE : RLC_UM_MODE;
+  mapping->rlcMode_present = TRUE;
+
+
 
   return offset;
 }
@@ -27135,9 +27205,23 @@ static const per_sequence_t RLC_BearerConfig_sequence[] = {
 
 static int
 dissect_nr_rrc_RLC_BearerConfig(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  struct mac_nr_info *p_mac_nr_info;
+  /* Get the struct and clear it out */
+  nr_drb_mapping_t *drb_mapping = &nr_rrc_get_private_data(actx)->drb_mapping;
+  memset(drb_mapping, 0, sizeof(nr_drb_mapping_t));
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_nr_rrc_RLC_BearerConfig, RLC_BearerConfig_sequence);
 
+  /* Need UE identifier */
+  p_mac_nr_info = (mac_nr_info *)p_get_proto_data(wmem_file_scope(), actx->pinfo, proto_mac_nr, 0);
+  if (p_mac_nr_info) {
+    drb_mapping->ueid = p_mac_nr_info->ueid;
+    /* Tell MAC about this mapping */
+    set_mac_nr_bearer_mapping(drb_mapping);
+  }
+
+
+
   return offset;
 }
 
@@ -41815,7 +41899,7 @@ static int dissect_SystemInformation_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _
 
 
 /*--- End of included file: packet-nr-rrc-fn.c ---*/
-#line 353 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 360 "./asn1/nr-rrc/packet-nr-rrc-template.c"
 
 void
 proto_register_nr_rrc(void) {
@@ -53164,7 +53248,7 @@ proto_register_nr_rrc(void) {
         NULL, HFILL }},
 
 /*--- End of included file: packet-nr-rrc-hfarr.c ---*/
-#line 361 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 368 "./asn1/nr-rrc/packet-nr-rrc-template.c"
 
     { &hf_nr_rrc_serialNumber_gs,
       { "Geographical Scope", "nr-rrc.serialNumber.gs",
@@ -54465,7 +54549,7 @@ proto_register_nr_rrc(void) {
     &ett_nr_rrc_OverheatingAssistanceConfig,
 
 /*--- End of included file: packet-nr-rrc-ettarr.c ---*/
-#line 495 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 502 "./asn1/nr-rrc/packet-nr-rrc-template.c"
     &ett_nr_rrc_DedicatedNAS_Message,
     &ett_rr_rrc_targetRAT_MessageContainer,
     &ett_nr_rrc_nas_Container,
@@ -54516,7 +54600,7 @@ proto_register_nr_rrc(void) {
 
 
 /*--- End of included file: packet-nr-rrc-dis-reg.c ---*/
-#line 527 "./asn1/nr-rrc/packet-nr-rrc-template.c"
+#line 534 "./asn1/nr-rrc/packet-nr-rrc-template.c"
 
   nr_rrc_etws_cmas_dcs_hash = wmem_map_new_autoreset(wmem_epan_scope(), wmem_file_scope(),
                                                      g_direct_hash, g_direct_equal);