Update scsi lun id dissector, add support to handle all 4 addressing

methods

Bug 11078

Change-Id: I7a9ff07d83b4bb5f5512c04d71aa7f1d3baa0edd
Reviewed-on: https://code.wireshark.org/review/8181
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

2 files changed, 142 insertions, 31 deletions

diff --git a/epan/dissectors/packet-iscsi.c b/epan/dissectors/packet-iscsi.c
index 1e79d01d26..3a0ac1239a 100644
--- a/epan/dissectors/packet-iscsi.c
+++ b/epan/dissectors/packet-iscsi.c
@@ -2105,10 +2105,6 @@ dissect_iscsi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean chec
         if(tvb_get_letohs(tvb,offset+2)){
             return 0;
         }
-        /* last 6 bytes of LUN are always 0 */
-        if(tvb_get_ntoh48(tvb, offset+10)){
-            return 0;
-        }
         /* if expected data transfer length is set, W and/or R have to be set */
         if(tvb_get_ntohl(tvb,offset+20)){
             if(!(tvb_get_guint8(tvb, offset+1)&0x60)){
diff --git a/epan/dissectors/packet-scsi.c b/epan/dissectors/packet-scsi.c
index b47831f5aa..914df400f0 100644
--- a/epan/dissectors/packet-scsi.c
+++ b/epan/dissectors/packet-scsi.c
@@ -173,7 +173,11 @@ static int hf_scsi_inq_rmb                      = -1;
 static int hf_scsi_inq_version                  = -1;
 static int hf_scsi_lun_address_mode             = -1;
 static int hf_scsi_lun                          = -1;
+static int hf_scsi_lun_extended                 = -1;
+static int hf_scsi_extended_add_method_len      = -1;
+static int hf_scsi_extended_add_method          = -1;
 static int hf_scsi_bus                          = -1;
+static int hf_scsi_target                       = -1;
 static int hf_scsi_modesns_errrep               = -1;
 static int hf_scsi_modesns_tst                  = -1;
 static int hf_scsi_modesns_qmod                 = -1;
@@ -738,6 +742,7 @@ static gint ett_scsi_fragments = -1;
 static gint ett_scsi_fragment = -1;
 static gint ett_persresv_control = -1;
 static gint ett_scsi_lun = -1;
+static gint ett_scsi_lun_unit = -1;
 static gint ett_scsi_prevent_allow = -1;
 static gint ett_command_descriptor = -1;
 static gint ett_timeout_descriptor = -1;
@@ -855,8 +860,9 @@ static const value_string scsi_spc_vals[] = {
 static value_string_ext scsi_spc_vals_ext = VALUE_STRING_EXT_INIT(scsi_spc_vals);
 
 static const value_string scsi_lun_address_mode_vals[] = {
-    { 0, "Single Level LUN Structure" },
+    { 0, "Peripheral Device Addressing Method" },
     { 1, "Flat Space Addressing Method" },
+    { 2, "Logical Unit Addressing Method" },
     { 3, "Extended Logical Unit Addressing" },
     { 0, NULL }
 };
@@ -4987,31 +4993,125 @@ dissect_spc_reportdeviceidentifier(tvbuff_t *tvb _U_, packet_info *pinfo _U_,
 void
 dissect_scsi_lun(proto_tree *tree, tvbuff_t *tvb, guint offset) {
     proto_item *ti;
-    proto_tree *tt = proto_tree_add_subtree(tree, tvb, offset, 8, ett_scsi_lun, &ti, "LUN: ");
-    guint8 address_mode;
+    proto_tree *tt, *tl = proto_tree_add_subtree(tree, tvb, offset, 8, ett_scsi_lun, &ti, "LUN");
+    guint8 address_mode, lun_len = 0, ea_code = 0, len_code = 0, lun_count = 0, complex_lun = 0;
     guint16 lun = 0;
+    const gchar *str = NULL;
 
-    address_mode = tvb_get_guint8(tvb, offset) >> 6;
-    proto_tree_add_item(tt, hf_scsi_lun_address_mode, tvb, offset, 1, ENC_BIG_ENDIAN);
-
-    switch (address_mode) {
-    case 0:
-        proto_tree_add_item(tt, hf_scsi_bus, tvb, offset, 1, ENC_BIG_ENDIAN);
-        lun = tvb_get_guint8(tvb, offset + 1);
-        proto_tree_add_uint(tt, hf_scsi_lun, tvb, offset + 1, 1, lun);
-        break;
-    case 1:
-        lun = tvb_get_ntohs(tvb, offset) & 0x3fff;
-        proto_tree_add_uint(tt, hf_scsi_lun, tvb, offset, 2, lun);
-        break;
-/*
-    This mode is complex. Lets implement it if/once we see this mode used in the wild.
-    case 3:
-        break;
- */
+    if (tvb_get_ntoh48(tvb, offset) << 16) {
+        /* Pedantically change LUN to LUNs */
+        proto_item_append_text(tl, "s");
+        complex_lun = 1;
     }
 
-    proto_item_append_text(ti, "%d (%s)", lun, val_to_str(address_mode, scsi_lun_address_mode_vals, "Unknown Address Mode:%d"));
+    while (lun_len < 8) {
+        lun = tvb_get_ntohs(tvb, offset + lun_len);
+        /* Don't skip the first non-zero LUN */
+        if (lun_len && !lun)
+            break;
+
+        address_mode = tvb_get_guint8(tvb, offset + lun_len);
+        if ((address_mode >> 6) < 0x3)
+            len_code = 2;
+        else {
+            len_code = (address_mode & 0x30) >> 4;
+            len_code = 2 + (len_code * 2);
+        }
+
+        if (complex_lun) {
+            /* Add lun subtrees only for complex luns */
+            tt = proto_tree_add_subtree(tl, tvb, offset + lun_len, len_code, ett_scsi_lun_unit, &ti, "LUN");
+            proto_item_append_text(tt, " %d", lun_count++);
+        } else
+            tt = tl;
+
+        /* Peripheral and Simple logical unit addressing share the same identifier, with bus defining the difference */
+        if (!address_mode)
+            proto_tree_add_uint_format_value(tt, hf_scsi_lun_address_mode, tvb, offset + lun_len, 1, (address_mode >> 6),
+                                             "Simple logical unit addressing (0x0%x)", address_mode >> 6);
+        else
+            proto_tree_add_item(tt, hf_scsi_lun_address_mode, tvb, offset + lun_len, 1, ENC_BIG_ENDIAN);
+
+        switch (address_mode >> 6) {
+        case 0:
+            /*  Simple logical unit addressing method has no bus id */
+            if (address_mode) {
+                proto_tree_add_bits_item(tt, hf_scsi_bus, tvb, (offset + lun_len) * 8 + 2, 0x6, ENC_BIG_ENDIAN);
+                lun = tvb_get_guint8(tvb, offset + lun_len + 1);
+                proto_tree_add_uint(tt, hf_scsi_lun, tvb, offset + lun_len + 1, 1, lun);
+            } else {
+                lun &= 0x3fff;
+                proto_tree_add_bits_item(tt, hf_scsi_lun, tvb, (offset + lun_len) * 8 + 2, 0xe, ENC_BIG_ENDIAN);
+            }
+            lun_len += len_code;
+            break;
+
+        case 1:
+            lun &= 0x3fff;
+            proto_tree_add_bits_item(tt, hf_scsi_lun, tvb, (offset + lun_len) * 8 + 2, 0xe, ENC_BIG_ENDIAN);
+            lun_len += len_code;
+            break;
+        case 2:
+            proto_tree_add_item(tt, hf_scsi_target, tvb, offset + lun_len, 1, ENC_BIG_ENDIAN);
+            proto_tree_add_bits_item(tt, hf_scsi_bus, tvb, (offset + lun_len + 1) * 8, 0x3, ENC_BIG_ENDIAN);
+            proto_tree_add_bits_item(tt, hf_scsi_lun, tvb, (offset + lun_len + 1) * 8 + 3, 0x5, ENC_BIG_ENDIAN);
+            lun_len += len_code;
+            break;
+        case 3:
+            ea_code = address_mode & 0xf;
+            lun = len_code;
+            len_code = (address_mode & 0x30) >> 4;
+
+            ti = proto_tree_add_item(tt, hf_scsi_extended_add_method_len, tvb, offset + lun_len, 1, ENC_BIG_ENDIAN);
+            proto_item_append_text(ti, " (%d bytes)", lun);
+
+            ti = proto_tree_add_item(tt, hf_scsi_extended_add_method, tvb, offset + lun_len, 1, ENC_BIG_ENDIAN);
+
+            str = NULL;
+            switch(ea_code) {
+            case 0x1:
+                if (!len_code) {
+                    str = "Well known logical unit";
+                    proto_tree_add_item(tt, hf_scsi_lun, tvb, offset + lun_len + 1, 1, ENC_BIG_ENDIAN);
+                }
+                break;
+            case 0x2:
+                if (len_code == 0x1)
+                    str = "Extended flat space addressing";
+                else if (len_code == 0x2)
+                    str = "Long extended flat space addressing";
+                if (str)
+                    proto_tree_add_item(tt, hf_scsi_lun_extended, tvb, offset + lun_len + 1, lun - 1, ENC_BIG_ENDIAN);
+                break;
+            case 0xe:
+                if (len_code == 0x3)
+                    str = "Reserved for FC-SB-5";
+                break;
+            case 0xf:
+                /* The contents of all hierarchical LUN structure addressing fields following a logical unit not specified addressing
+                 * method addressing field shall be ignored. [SAM5] 4.7.7.5.4 */
+                if (len_code == 0x3) {
+                    proto_item_append_text(ti, " (Logical unit not specified)");
+                    return;
+                }
+                break;
+            default:
+                str = "Reserved";
+                break;
+            }
+
+            len_code = (guint8)lun;
+            if (!str)
+                str = "Reserved";
+
+            proto_item_append_text(ti, " (%s)", str);
+            lun_len += len_code;
+            break;
+
+        default:
+            break;
+        }
+    }
 }
 
 void
@@ -6950,14 +7050,28 @@ proto_register_scsi(void)
           {"Maximum Sense Data Length", "scsi.spc.modepage.msdl", FT_UINT8, BASE_DEC,
            NULL, 0, NULL, HFILL}},
         { &hf_scsi_lun,
-          { "LUN", "scsi.lun", FT_UINT16, BASE_DEC,
-            NULL, 0, "Logical Unit Number", HFILL }},
+          { "LUN", "scsi.lun", FT_UINT16, BASE_HEX,
+           NULL, 0, "Logical Unit Number", HFILL }},
+        { &hf_scsi_lun_extended,
+          { "LUN", "scsi.lun_long", FT_UINT64, BASE_HEX,
+           NULL, 0, "Logical Unit Number", HFILL }},
+        /* hf_scsi_bus has length of 0x6 with 2bit offset, or 0x3 with no offset
+           so we handle it with add_bits_item */
         { &hf_scsi_bus,
-          { "BUS", "scsi.bus", FT_UINT8, BASE_DEC,
-            NULL, 0x3f, NULL, HFILL }},
+          { "BUS", "scsi.bus", FT_UINT8, BASE_HEX,
+           NULL, 0, NULL, HFILL }},
+        { &hf_scsi_target,
+          { "Target", "scsi.target", FT_UINT8, BASE_HEX,
+           NULL, 0x3f, NULL, HFILL }},
         { &hf_scsi_lun_address_mode,
-          { "Address Mode", "scsi.lun.address_mode", FT_UINT8, BASE_DEC,
+          { "Address Mode", "scsi.lun.address_mode", FT_UINT8, BASE_HEX,
           VALS(scsi_lun_address_mode_vals), 0xc0, "Addressing mode for the LUN", HFILL }},
+        { &hf_scsi_extended_add_method_len,
+          { "Extended Address Method Length", "scsi.lun.extended_address_method.len", FT_UINT8, BASE_HEX,
+          NULL, 0x30, "Extended Address Method Specific Field", HFILL }},
+        { &hf_scsi_extended_add_method,
+          { "Extended Address Method", "scsi.lun.extended_address_method", FT_UINT8, BASE_HEX,
+          NULL, 0xf, "Extended Logical Unit Addressing", HFILL }},
         { &hf_scsi_prevent_allow_flags,
           {"Prevent Allow Flags", "scsi.prevent_allow.flags", FT_UINT8, BASE_HEX, NULL, 0,
            NULL, HFILL}},
@@ -7403,6 +7517,7 @@ proto_register_scsi(void)
         &ett_scsi_fragment,
         &ett_persresv_control,
         &ett_scsi_lun,
+        &ett_scsi_lun_unit,
         &ett_scsi_prevent_allow,
         &ett_command_descriptor,
         &ett_timeout_descriptor,