Improve dissection of bit-oriented fields. Patch from Richard Sharpe via

bug #5466 with some minor whitespace modifications from me and a fix of an
invalid offset introduced with the patch.  Fuzz testing still needs to be done.
I can't seem to get the fuzz tester to work with the capture files attached to
the bug report. 

svn path=/trunk/; revision=35137

1 files changed, 92 insertions, 223 deletions

diff --git a/epan/dissectors/packet-scsi-ssc.c b/epan/dissectors/packet-scsi-ssc.c
index 15a6df8658..260ea074cc 100644
--- a/epan/dissectors/packet-scsi-ssc.c
+++ b/epan/dissectors/packet-scsi-ssc.c
@@ -103,7 +103,6 @@ dissect_ssc_read6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *read6_fields[] = {
 	&hf_scsi_ssc_sili,
 	&hf_scsi_ssc_fixed,
@@ -117,14 +116,11 @@ dissect_ssc_read6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, read6_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, read6_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3, 0);
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -133,7 +129,6 @@ dissect_ssc_recoverbuffereddata (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tr
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *recover_fields[] = {
 	&hf_scsi_ssc_sili,
 	&hf_scsi_ssc_fixed,
@@ -147,14 +142,11 @@ dissect_ssc_recoverbuffereddata (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tr
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, recover_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, recover_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3, 0);
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -163,7 +155,6 @@ dissect_ssc_reportdensitysupport (tvbuff_t *tvb, packet_info *pinfo _U_, proto_t
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *rd_fields[] = {
 	&hf_scsi_ssc_medium_type,
 	&hf_scsi_ssc_media,
@@ -180,14 +171,11 @@ dissect_ssc_reportdensitysupport (tvbuff_t *tvb, packet_info *pinfo _U_, proto_t
         return;
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, rd_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, rd_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+6, 2, 0);
-        flags = tvb_get_guint8 (tvb, offset+8);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+8, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+8, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     } else {
         /* XXX decode the data */
     }
@@ -198,7 +186,6 @@ dissect_ssc_readreverse6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tre
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *rr6_fields[] = {
 	&hf_scsi_ssc_bytord,
 	&hf_scsi_ssc_sili,
@@ -213,14 +200,11 @@ dissect_ssc_readreverse6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tre
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, rr6_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, rr6_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3, 0);
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -229,7 +213,6 @@ dissect_ssc_read16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *read6_fields[] = {
 	&hf_scsi_ssc_sili,
 	&hf_scsi_ssc_fixed,
@@ -243,19 +226,13 @@ dissect_ssc_read16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, read6_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, read6_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_locate16_loid, tvb, offset+3, 8, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+11, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -264,7 +241,6 @@ dissect_ssc_write16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *write16_fields[] = {
 	&hf_scsi_ssc_fcs,
 	&hf_scsi_ssc_lcs,
@@ -279,19 +255,13 @@ dissect_ssc_write16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, write16_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, write16_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_locate16_loid, tvb, offset+3, 8, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+11, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -300,7 +270,6 @@ dissect_ssc_writefilemarks16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *wf16_fields[] = {
 	&hf_scsi_ssc_fcs,
 	&hf_scsi_ssc_lcs,
@@ -315,19 +284,13 @@ dissect_ssc_writefilemarks16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, wf16_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, wf16_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_locate16_loid, tvb, offset+3, 8, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+11, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -336,7 +299,6 @@ dissect_ssc_verify16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *verify16_fields[] = {
 	&hf_scsi_ssc_verify16_immed,
 	&hf_scsi_ssc_bytcmp,
@@ -351,19 +313,13 @@ dissect_ssc_verify16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, verify16_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, verify16_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_locate16_loid, tvb, offset+3, 8, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_ver16_verlen, tvb, offset+11, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -372,7 +328,6 @@ dissect_ssc_verify6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *verify6_fields[] = {
 	&hf_scsi_ssc_verify16_immed,
 	&hf_scsi_ssc_bytcmp,
@@ -387,15 +342,11 @@ dissect_ssc_verify6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, verify6_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, verify6_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_ver16_verlen, tvb, offset+1, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -404,7 +355,6 @@ dissect_ssc_readreverse16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tr
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *rr16_fields[] = {
 	&hf_scsi_ssc_bytord,
 	&hf_scsi_ssc_sili,
@@ -419,19 +369,13 @@ dissect_ssc_readreverse16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tr
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, rr16_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, rr16_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_locate16_loid, tvb, offset+3, 8, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+11, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -440,7 +384,6 @@ dissect_ssc_write6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *write6_fields[] = {
 	&hf_scsi_ssc_immed,
 	NULL
@@ -453,16 +396,11 @@ dissect_ssc_write6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, write6_fields, FALSE);
-
-        proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3,
-                             FALSE);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, write6_fields, FALSE);
+        proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3, FALSE);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -471,7 +409,6 @@ dissect_ssc_writefilemarks6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *wf6_fields[] = {
 	&hf_scsi_ssc_immed,
 	NULL
@@ -484,16 +421,11 @@ dissect_ssc_writefilemarks6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *
     }
 
     if (tree && isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, wf6_fields, FALSE);
-
-        proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3,
-                             FALSE);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, wf6_fields, FALSE);
+        proto_tree_add_item (tree, hf_scsi_ssc_rdwr6_xferlen, tvb, offset+1, 3, FALSE);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -502,7 +434,6 @@ dissect_ssc_loadunload (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *loadunload_immed_fields[] = {
 	&hf_scsi_ssc_immed,
 	NULL
@@ -526,15 +457,12 @@ dissect_ssc_loadunload (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
 
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_loadunload_immed_flags, ett_scsi_loadunload_immed, loadunload_immed_fields, FALSE);
-
-	proto_tree_add_bitmask(tree, tvb, offset+3, hf_scsi_ssc_loadunload_flags, ett_scsi_loadunload, loadunload_fields, FALSE);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_loadunload_immed_flags,
+            ett_scsi_loadunload_immed, loadunload_immed_fields, FALSE);
+        proto_tree_add_bitmask(tree, tvb, offset+3, hf_scsi_ssc_loadunload_flags,
+            ett_scsi_loadunload, loadunload_fields, FALSE);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -544,17 +472,14 @@ dissect_ssc_readblocklimits (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags, granularity;
+    guint8 granularity;
 
     if (!tree)
         return;
 
     if (isreq && iscdb) {
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
     else if (!iscdb) {
     	granularity = tvb_get_guint8 (tvb, offset);
@@ -573,7 +498,6 @@ dissect_ssc_rewind (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *rewind_fields[] = {
 	&hf_scsi_ssc_immed,
 	NULL
@@ -587,13 +511,9 @@ dissect_ssc_rewind (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
             col_append_fstr (pinfo->cinfo, COL_INFO, "(Immed: %u)",
                              tvb_get_guint8 (tvb, offset) & 0x01);
 
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, rewind_fields, FALSE);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, rewind_fields, FALSE);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -602,7 +522,6 @@ dissect_ssc_setcapacity (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *sc_fields[] = {
 	&hf_scsi_ssc_immed,
 	NULL
@@ -612,15 +531,11 @@ dissect_ssc_setcapacity (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree
         return;
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags, ett_scsi_read6, sc_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_read6_flags,
+            ett_scsi_read6, sc_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_capacity_prop_value, tvb, offset+2, 2, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -630,7 +545,6 @@ dissect_ssc_locate10 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *locate_fields[] = {
 	&hf_scsi_ssc_bt,
 	&hf_scsi_ssc_cp,
@@ -642,17 +556,12 @@ dissect_ssc_locate10 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
         return;
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_locate_flags, ett_scsi_locate, locate_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_locate_flags,
+            ett_scsi_locate, locate_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_locate10_loid, tvb, offset+2, 4, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+7, 1, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+8);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+8, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+8, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -662,7 +571,6 @@ dissect_ssc_locate16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *locate_fields[] = {
 	&hf_scsi_ssc_dest_type,
 	&hf_scsi_ssc_cp,
@@ -678,19 +586,14 @@ dissect_ssc_locate16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
         return;
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_locate_flags, ett_scsi_locate, locate_fields, FALSE);
-
-	proto_tree_add_bitmask(tree, tvb, offset+1, hf_scsi_ssc_bam_flags, ett_scsi_bam, bam_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_locate_flags,
+            ett_scsi_locate, locate_fields, FALSE);
+        proto_tree_add_bitmask(tree, tvb, offset+1, hf_scsi_ssc_bam_flags,
+            ett_scsi_bam, bam_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_locate16_loid, tvb, offset+3, 8, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -712,11 +615,8 @@ dissect_ssc_erase6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                              (flags & 0x02) >> 1,
                              flags & 0x01);
 
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -726,7 +626,6 @@ dissect_ssc_erase16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *erase16_fields[] = {
 	&hf_scsi_ssc_fcs,
 	&hf_scsi_ssc_lcs,
@@ -739,41 +638,28 @@ dissect_ssc_erase16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
         return;
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_erase_flags, ett_scsi_erase, erase16_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_erase_flags,
+            ett_scsi_erase, erase16_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_partition, tvb, offset+2, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_lbi, tvb, offset+3, 8, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
-
 static void
 dissect_ssc_space6 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
-
     if (!tree)
         return;
 
     if (isreq && iscdb) {
         proto_tree_add_item (tree, hf_scsi_ssc_space6_code, tvb, offset, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_space6_count, tvb, offset+1, 3, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -782,25 +668,17 @@ dissect_ssc_space16 (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree,
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
-
     if (!tree)
         return;
 
     if (isreq && iscdb) {
         proto_tree_add_item (tree, hf_scsi_ssc_space6_code, tvb, offset, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_space16_count, tvb, offset+3, 8, 0);
-
         proto_tree_add_text (tree, tvb, offset+11, 2,
                              "Parameter Len: %u",
                              tvb_get_ntohs (tvb, offset+11));
-
-        flags = tvb_get_guint8 (tvb, offset+14);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+14, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+14, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -830,7 +708,6 @@ dissect_ssc_formatmedium (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tre
                     guint offset, gboolean isreq, gboolean iscdb,
                     guint payload_len _U_, scsi_task_data_t *cdata _U_)
 {
-    guint8 flags;
     static const int *formatmedium_fields[] = {
 	&hf_scsi_ssc_verify,
 	&hf_scsi_ssc_immed,
@@ -841,17 +718,12 @@ dissect_ssc_formatmedium (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tre
         return;
 
     if (isreq && iscdb) {
-	proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_formatmedium_flags, ett_scsi_formatmedium, formatmedium_fields, FALSE);
-
+        proto_tree_add_bitmask(tree, tvb, offset, hf_scsi_ssc_formatmedium_flags,
+            ett_scsi_formatmedium, formatmedium_fields, FALSE);
         proto_tree_add_item (tree, hf_scsi_ssc_format, tvb, offset+1, 1, 0);
-
         proto_tree_add_item (tree, hf_scsi_ssc_rdwr10_xferlen, tvb, offset+2, 2, 0);
-
-        flags = tvb_get_guint8 (tvb, offset+4);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+4, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+4, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
 }
 
@@ -886,11 +758,8 @@ dissect_ssc_readposition (tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tre
         proto_tree_add_text (tree, tvb, offset+6, 2,
                              "Parameter Len: %u",
                              tvb_get_ntohs (tvb, offset+6));
-        flags = tvb_get_guint8 (tvb, offset+8);
-        proto_tree_add_uint_format (tree, hf_scsi_control, tvb, offset+8, 1,
-                                    flags,
-                                    "Vendor Unique = %u, NACA = %u, Link = %u",
-                                    flags & 0xC0, flags & 0x4, flags & 0x1);
+        proto_tree_add_bitmask(tree, tvb, offset+8, hf_scsi_control,
+            ett_scsi_control, cdb_control_fields, FALSE);
     }
     else if (!isreq) {
         if (cdata)