RRC: Improve C-RNTI resolving

Now also trying to resolve C-RNTIs in FACH from the global RNTIs map

Change-Id: If9ce5b73d6855271c15001fd73d8acaaaf9d1864
Reviewed-on: https://code.wireshark.org/review/24665
Reviewed-by: Pascal Quantin <pascal.quantin@gmail.com>
Petri-Dish: Pascal Quantin <pascal.quantin@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Michael Mann <mmann78@netscape.net>

7 files changed, 54 insertions, 42 deletions

diff --git a/epan/dissectors/asn1/rrc/packet-rrc-template.c b/epan/dissectors/asn1/rrc/packet-rrc-template.c
index d190d1c8f4..d891866dfc 100644
--- a/epan/dissectors/asn1/rrc/packet-rrc-template.c
+++ b/epan/dissectors/asn1/rrc/packet-rrc-template.c
@@ -65,7 +65,7 @@ extern int proto_umts_rlc; /*Handler to RLC*/
 
 GTree * hsdsch_muxed_flows = NULL;
 GTree * rrc_ciph_info_tree = NULL;
-wmem_tree_t* rrc_rach_urnti_crnti_map = NULL;
+wmem_tree_t* rrc_global_urnti_crnti_map = NULL;
 static int msg_type _U_;
 
 /*****************************************************************************/
@@ -462,7 +462,7 @@ rrc_init(void) {
                        rrc_free_value);
 
     /* Global U-RNTI / C-RNTI map to be used in RACH channels */
-    rrc_rach_urnti_crnti_map = wmem_tree_new_autoreset(wmem_epan_scope(), wmem_file_scope());
+    rrc_global_urnti_crnti_map = wmem_tree_new_autoreset(wmem_epan_scope(), wmem_file_scope());
 }
 
 static void
diff --git a/epan/dissectors/asn1/rrc/packet-rrc-template.h b/epan/dissectors/asn1/rrc/packet-rrc-template.h
index f6c287c57c..bb0e5e3662 100644
--- a/epan/dissectors/asn1/rrc/packet-rrc-template.h
+++ b/epan/dissectors/asn1/rrc/packet-rrc-template.h
@@ -60,6 +60,6 @@ typedef struct rrc_ciphering_info
 
 extern GTree * hsdsch_muxed_flows;
 extern GTree * rrc_ciph_info_tree;
-extern wmem_tree_t* rrc_rach_urnti_crnti_map;
+extern wmem_tree_t* rrc_global_urnti_crnti_map;
 
 #endif  /* PACKET_RRC_H */
diff --git a/epan/dissectors/asn1/rrc/rrc.cnf b/epan/dissectors/asn1/rrc/rrc.cnf
index 4837a7c887..b677d67674 100644
--- a/epan/dissectors/asn1/rrc/rrc.cnf
+++ b/epan/dissectors/asn1/rrc/rrc.cnf
@@ -1069,9 +1069,10 @@ HNBName TYPE=FT_STRING DISPLAY=STR_UNICODE
     return offset;
 
   /* Both U-RNTI and C-RNTI present - storing the match*/
-  fp_crnti_allocation_info = wmem_new0(wmem_file_scope(), fp_crnti_allocation_info_t);
+  fp_crnti_allocation_info = wmem_new(wmem_file_scope(), fp_crnti_allocation_info_t);
   fp_crnti_allocation_info->urnti = u_rnti;
   fp_crnti_allocation_info->alloc_frame_number = actx->pinfo->num;
+  fp_crnti_allocation_info->global_retrieval_count = 0;
 
   /* Finding FP conversation info */
   p_conv = (conversation_t *)find_conversation(actx->pinfo->num, &actx->pinfo->net_dst, &actx->pinfo->net_src,
@@ -1090,7 +1091,7 @@ HNBName TYPE=FT_STRING DISPLAY=STR_UNICODE
   }
 
   /* Also adding the C-RNTI / U-RNTI match to the global RNTIs map for the RACH channel */
-  wmem_tree_insert32(rrc_rach_urnti_crnti_map, c_rnti, (void *)fp_crnti_allocation_info);
+  wmem_tree_insert32(rrc_global_urnti_crnti_map, c_rnti, (void *)fp_crnti_allocation_info);
 
 #.FN_BODY UL-ScramblingCode VAL_PTR = &scrambling_code
 guint32 scrambling_code;
diff --git a/epan/dissectors/packet-rrc.c b/epan/dissectors/packet-rrc.c
index 3cd1dbd07c..1487918251 100644
--- a/epan/dissectors/packet-rrc.c
+++ b/epan/dissectors/packet-rrc.c
@@ -73,7 +73,7 @@ extern int proto_umts_rlc; /*Handler to RLC*/
 
 GTree * hsdsch_muxed_flows = NULL;
 GTree * rrc_ciph_info_tree = NULL;
-wmem_tree_t* rrc_rach_urnti_crnti_map = NULL;
+wmem_tree_t* rrc_global_urnti_crnti_map = NULL;
 static int msg_type _U_;
 
 /*****************************************************************************/
@@ -18577,7 +18577,7 @@ dissect_rrc_ActivationTime(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _
 
 static int
 dissect_rrc_RB_Identity(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1275 "./asn1/rrc/rrc.cnf"
+#line 1276 "./asn1/rrc/rrc.cnf"
 guint32 rbid;
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             1U, 32U, &rbid, FALSE);
@@ -18594,7 +18594,7 @@ private_data_set_rbid(actx, rbid);
 
 static int
 dissect_rrc_RLC_SequenceNumber(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1281 "./asn1/rrc/rrc.cnf"
+#line 1282 "./asn1/rrc/rrc.cnf"
 guint32 rlc_ciphering_sqn;
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, 4095U, &rlc_ciphering_sqn, FALSE);
@@ -18615,7 +18615,7 @@ static const per_sequence_t RB_ActivationTimeInfo_sequence[] = {
 
 static int
 dissect_rrc_RB_ActivationTimeInfo(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1247 "./asn1/rrc/rrc.cnf"
+#line 1248 "./asn1/rrc/rrc.cnf"
   fp_info            *fpinf;
   rlc_info           *rlcinf;
   rrc_ciphering_info *ciphering_info;
@@ -22593,7 +22593,7 @@ dissect_rrc_SSDT_UL(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, pro
 
 static int
 dissect_rrc_CellIdentity(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1101 "./asn1/rrc/rrc.cnf"
+#line 1102 "./asn1/rrc/rrc.cnf"
   tvbuff_t * cell_id_tvb = NULL;
   proto_item *temp_ti;
   proto_tree *cell_identity_tree;
@@ -22818,7 +22818,7 @@ dissect_rrc_T_r3(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_
 
 static int
 dissect_rrc_H_RNTI(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1189 "./asn1/rrc/rrc.cnf"
+#line 1190 "./asn1/rrc/rrc.cnf"
   tvbuff_t *hrnti_tvb;
   struct rrc_info *rrcinf;
   offset = dissect_per_bit_string(tvb, offset, actx, tree, hf_index,
@@ -22827,7 +22827,7 @@ dissect_rrc_H_RNTI(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, prot
 
 
 
-#line 1194 "./asn1/rrc/rrc.cnf"
+#line 1195 "./asn1/rrc/rrc.cnf"
   rrcinf = (struct rrc_info *)p_get_proto_data(wmem_file_scope(), actx->pinfo, proto_rrc, 0);
   if (!rrcinf) {
     rrcinf = wmem_new0(wmem_file_scope(), struct rrc_info);
@@ -28327,7 +28327,7 @@ dissect_rrc_ScramblingCodeType(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *ac
 
 static int
 dissect_rrc_UL_ScramblingCode(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1096 "./asn1/rrc/rrc.cnf"
+#line 1097 "./asn1/rrc/rrc.cnf"
 guint32 scrambling_code;
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, 16777215U, &scrambling_code, FALSE);
@@ -39120,9 +39120,10 @@ dissect_rrc_C_RNTI(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, prot
     return offset;
 
   /* Both U-RNTI and C-RNTI present - storing the match*/
-  fp_crnti_allocation_info = wmem_new0(wmem_file_scope(), fp_crnti_allocation_info_t);
+  fp_crnti_allocation_info = wmem_new(wmem_file_scope(), fp_crnti_allocation_info_t);
   fp_crnti_allocation_info->urnti = u_rnti;
   fp_crnti_allocation_info->alloc_frame_number = actx->pinfo->num;
+  fp_crnti_allocation_info->global_retrieval_count = 0;
 
   /* Finding FP conversation info */
   p_conv = (conversation_t *)find_conversation(actx->pinfo->num, &actx->pinfo->net_dst, &actx->pinfo->net_src,
@@ -39141,7 +39142,7 @@ dissect_rrc_C_RNTI(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, prot
   }
 
   /* Also adding the C-RNTI / U-RNTI match to the global RNTIs map for the RACH channel */
-  wmem_tree_insert32(rrc_rach_urnti_crnti_map, c_rnti, (void *)fp_crnti_allocation_info);
+  wmem_tree_insert32(rrc_global_urnti_crnti_map, c_rnti, (void *)fp_crnti_allocation_info);
 
 
 
@@ -46180,7 +46181,7 @@ dissect_rrc_RLC_Info_r5(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_,
 
 static int
 dissect_rrc_MAC_d_FlowIdentity(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1186 "./asn1/rrc/rrc.cnf"
+#line 1187 "./asn1/rrc/rrc.cnf"
   offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
                                                             0U, 7U, &flowd, FALSE);
 
@@ -46228,7 +46229,7 @@ static const per_choice_t DL_TransportChannelType_r5_choice[] = {
 
 static int
 dissect_rrc_DL_TransportChannelType_r5(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1115 "./asn1/rrc/rrc.cnf"
+#line 1116 "./asn1/rrc/rrc.cnf"
 /*Here we try to figure out which HS-DSCH channels are multiplexed*/
     guint *flowd_p;
     guint *cur_val=NULL;
@@ -49702,7 +49703,7 @@ static const per_choice_t DL_TransportChannelType_r7_choice[] = {
 
 static int
 dissect_rrc_DL_TransportChannelType_r7(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1150 "./asn1/rrc/rrc.cnf"
+#line 1151 "./asn1/rrc/rrc.cnf"
 /*Here we try to figure out which HS-DSCH channels are multiplexed*/
     guint *flowd_p;
     guint *cur_val=NULL;
@@ -90280,7 +90281,7 @@ static const value_string rrc_ReleaseCause_vals[] = {
 
 static int
 dissect_rrc_ReleaseCause(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1303 "./asn1/rrc/rrc.cnf"
+#line 1304 "./asn1/rrc/rrc.cnf"
   guint32 value;
   offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
                                      8, &value, FALSE, 0, NULL);
@@ -99800,7 +99801,7 @@ static const per_choice_t DL_DCCH_MessageType_choice[] = {
 
 static int
 dissect_rrc_DL_DCCH_MessageType(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1286 "./asn1/rrc/rrc.cnf"
+#line 1287 "./asn1/rrc/rrc.cnf"
   offset = dissect_per_choice(tvb, offset, actx, tree, hf_index,
                                  ett_rrc_DL_DCCH_MessageType, DL_DCCH_MessageType_choice,
                                  &msg_type);
@@ -99820,7 +99821,7 @@ static const per_sequence_t DL_DCCH_Message_sequence[] = {
 
 static int
 dissect_rrc_DL_DCCH_Message(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1289 "./asn1/rrc/rrc.cnf"
+#line 1290 "./asn1/rrc/rrc.cnf"
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_rrc_DL_DCCH_Message, DL_DCCH_Message_sequence);
 
@@ -99834,7 +99835,7 @@ dissect_rrc_DL_DCCH_Message(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx
 
 static int
 dissect_rrc_START_Value(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1202 "./asn1/rrc/rrc.cnf"
+#line 1203 "./asn1/rrc/rrc.cnf"
   tvbuff_t * start_val;
   fp_info       *fpinf;
   rlc_info      *rlcinf;
@@ -129619,7 +129620,7 @@ static const per_choice_t HandoverToUTRANCommand_choice[] = {
 
 static int
 dissect_rrc_HandoverToUTRANCommand(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1292 "./asn1/rrc/rrc.cnf"
+#line 1293 "./asn1/rrc/rrc.cnf"
   offset = dissect_per_choice(tvb, offset, actx, tree, hf_index,
                                  ett_rrc_HandoverToUTRANCommand, HandoverToUTRANCommand_choice,
                                  NULL);
@@ -129760,7 +129761,7 @@ static const per_sequence_t UE_SecurityInformation_sequence[] = {
 
 static int
 dissect_rrc_UE_SecurityInformation(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1295 "./asn1/rrc/rrc.cnf"
+#line 1296 "./asn1/rrc/rrc.cnf"
   private_data_set_cn_domain(actx, RRC_NAS_SYS_INFO_CS);
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_rrc_UE_SecurityInformation, UE_SecurityInformation_sequence);
@@ -130163,7 +130164,7 @@ static const per_sequence_t UE_SecurityInformation2_sequence[] = {
 
 static int
 dissect_rrc_UE_SecurityInformation2(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
-#line 1299 "./asn1/rrc/rrc.cnf"
+#line 1300 "./asn1/rrc/rrc.cnf"
   private_data_set_cn_domain(actx, RRC_NAS_SYS_INFO_PS);
   offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
                                    ett_rrc_UE_SecurityInformation2, UE_SecurityInformation2_sequence);
@@ -163265,7 +163266,7 @@ rrc_init(void) {
                        rrc_free_value);
 
     /* Global U-RNTI / C-RNTI map to be used in RACH channels */
-    rrc_rach_urnti_crnti_map = wmem_tree_new_autoreset(wmem_epan_scope(), wmem_file_scope());
+    rrc_global_urnti_crnti_map = wmem_tree_new_autoreset(wmem_epan_scope(), wmem_file_scope());
 }
 
 static void
diff --git a/epan/dissectors/packet-rrc.h b/epan/dissectors/packet-rrc.h
index 7e0a553269..309d96ce23 100644
--- a/epan/dissectors/packet-rrc.h
+++ b/epan/dissectors/packet-rrc.h
@@ -84,6 +84,6 @@ typedef struct rrc_ciphering_info
 
 extern GTree * hsdsch_muxed_flows;
 extern GTree * rrc_ciph_info_tree;
-extern wmem_tree_t* rrc_rach_urnti_crnti_map;
+extern wmem_tree_t* rrc_global_urnti_crnti_map;
 
 #endif  /* PACKET_RRC_H */
diff --git a/epan/dissectors/packet-umts_fp.h b/epan/dissectors/packet-umts_fp.h
index 7718b7b996..1714f78a6a 100644
--- a/epan/dissectors/packet-umts_fp.h
+++ b/epan/dissectors/packet-umts_fp.h
@@ -112,6 +112,7 @@ typedef struct fp_crnti_allocation_info_t
 {
     guint32 alloc_frame_number; /* Frame where C-RNTI was allocated */
     guint32 urnti; /* The U-RNTI to which the C-RNTI was allocated*/
+    guint32 global_retrieval_count; /* How many times this alloc info was retrieved for FACH channels*/
 } fp_crnti_allocation_info_t;
 
 /* Used in the 'channel_specific_info' field for FACH channels */
diff --git a/epan/dissectors/packet-umts_mac.c b/epan/dissectors/packet-umts_mac.c
index 174b5934ae..1e9531ed65 100644
--- a/epan/dissectors/packet-umts_mac.c
+++ b/epan/dissectors/packet-umts_mac.c
@@ -238,6 +238,7 @@ static guint16 tree_add_common_dcch_dtch_fields(tvbuff_t *tvb, packet_info *pinf
     umts_fp_conversation_info_t *umts_fp_conversation_info = NULL;
     fp_rach_channel_info_t *fp_rach_channel_info = NULL;
     fp_fach_channel_info_t *fp_fach_channel_info = NULL;
+    wmem_tree_t* channel_rnti_map = NULL;
     guint16 c_rnti;
     fp_crnti_allocation_info_t *fp_crnti_allocation_info = NULL;
 
@@ -260,35 +261,43 @@ static guint16 tree_add_common_dcch_dtch_fields(tvbuff_t *tvb, packet_info *pinf
         /* Trying to resolve the U-RNTI for this C-RNTI based on the channel type*/
         switch(fpinf->channel){
             case CHANNEL_RACH_FDD:
-                /* In RACH: First look in the channel's RNTIs map */
+                /* In RACH: Get the channel's RNTIs map */
                 if (umts_fp_conversation_info) {
                     fp_rach_channel_info = (fp_rach_channel_info_t *)umts_fp_conversation_info->channel_specific_info;
                     if(fp_rach_channel_info) {
-                        fp_crnti_allocation_info = (fp_crnti_allocation_info_t *)wmem_tree_lookup32(fp_rach_channel_info->crnti_to_urnti_map, c_rnti);
-                    }
-                }
-                if(fp_crnti_allocation_info == NULL) {
-                    /* If not found in the channel's map, Look in the global RNTIs map */
-                    fp_crnti_allocation_info = (fp_crnti_allocation_info_t *)wmem_tree_lookup32(rrc_rach_urnti_crnti_map, c_rnti);
-                    if(fp_crnti_allocation_info != NULL) {
-                        /* If found in the global map, remove and insert to the channel's map*/
-                        wmem_tree_remove32(rrc_rach_urnti_crnti_map, c_rnti);
-                        if(fp_rach_channel_info) {
-                            wmem_tree_insert32(fp_rach_channel_info->crnti_to_urnti_map, c_rnti, (void *)fp_crnti_allocation_info);
-                        }
+                        channel_rnti_map = fp_rach_channel_info->crnti_to_urnti_map;
                     }
                 }
                 break;
             case CHANNEL_FACH_FDD:
-                /* In FACH: Look in the channel's RNTIs map */
+                /* In FACH: Get the channel's RNTIs map */
                 if (umts_fp_conversation_info) {
                     fp_fach_channel_info = (fp_fach_channel_info_t *)umts_fp_conversation_info->channel_specific_info;
                     if(fp_fach_channel_info) {
-                        fp_crnti_allocation_info = (fp_crnti_allocation_info_t *)wmem_tree_lookup32(fp_fach_channel_info->crnti_to_urnti_map, c_rnti);
+                        channel_rnti_map = fp_fach_channel_info->crnti_to_urnti_map;
                     }
                 }
                 break;
         }
+        if(channel_rnti_map) {
+            fp_crnti_allocation_info = (fp_crnti_allocation_info_t *)wmem_tree_lookup32(channel_rnti_map, c_rnti);
+        }
+        /* If not found in the RACH/FACH channel's map, Look in the global RNTIs map */
+        if(fp_crnti_allocation_info == NULL) {
+            fp_crnti_allocation_info = (fp_crnti_allocation_info_t *)wmem_tree_lookup32(rrc_global_urnti_crnti_map, c_rnti);
+            if(fp_crnti_allocation_info != NULL) {
+                /* If found in the global map, check how many times it was retrieved (including this one) */
+                fp_crnti_allocation_info->global_retrieval_count++;
+                /* If seen 2 times (RACH + fast FACH) remove from global map */
+                if(fp_crnti_allocation_info->global_retrieval_count == 2) {
+                    wmem_tree_remove32(rrc_global_urnti_crnti_map, c_rnti);
+                }
+                /* Also add to this channel's map for later retrieval */
+                if(channel_rnti_map) {
+                    wmem_tree_insert32(channel_rnti_map, c_rnti, (void *)fp_crnti_allocation_info);
+                }
+            }
+        }
         /* Choosing between resolved U-RNTI (if found) or the C-RNTI as UE-ID for RLC */
         if(fp_crnti_allocation_info != NULL) {
             /* Using U-RNTI */