VLAN: Support IEEE 802.1Q-2005 and -2011 changes

Supports the recommended meanings of the priority field as
changed by 802.1Q-2005, and the change from the CFI to DEI
in 802.1Q-2011. A preference is added to use the older
(non-compatible) spec version. Note that 802.1Q-2011 is
consistent with 802.1ad and ah, which got rolled up in 802.1Q,
but ends up removing support for bridging Token Ring and FDDI
over Ethernet.

Bug: 13294
Change-Id: Ieeadb0f6dda2758750f9e6649f1390609d78c50e
Reviewed-on: https://code.wireshark.org/review/19548
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Michael Mann <mmann78@netscape.net>

1 files changed, 174 insertions, 20 deletions

diff --git a/epan/dissectors/packet-vlan.c b/epan/dissectors/packet-vlan.c
index ff9c0209f4..76aedfeaa9 100644
--- a/epan/dissectors/packet-vlan.c
+++ b/epan/dissectors/packet-vlan.c
@@ -43,6 +43,22 @@ static unsigned int q_in_q_ethertype = ETHERTYPE_QINQ_OLD;
 
 static gboolean vlan_summary_in_tree = TRUE;
 
+enum version_value {
+  IEEE_8021Q_1998,
+  IEEE_8021Q_2005,
+  IEEE_8021Q_2011
+};
+
+static gint vlan_version = (gint)IEEE_8021Q_2011;
+
+enum priority_drop_value {
+  Priority_Drop_8P0D,
+  Priority_Drop_7P1D,
+  Priority_Drop_6P2D,
+  Priority_Drop_5P3D,
+};
+
+static gint vlan_priority_drop = (gint)Priority_Drop_8P0D;
 
 static dissector_handle_t vlan_handle;
 static dissector_handle_t ethertype_handle;
@@ -55,10 +71,12 @@ static header_field_info *hfi_vlan = NULL;
 #define VLAN_HFI_INIT HFI_INIT(proto_vlan)
 
 /* From Table G-2 of IEEE standard 802.1D-2004 */
-static const value_string pri_vals[] = {
+/* Note that 0 is the default priority, but is above 1 and 2.
+ * Priority order from lowest to highest is 1,2,0,3,4,5,6,7 */
+static const value_string pri_vals_old[] = {
+  { 0, "Best Effort (default)"             },
   { 1, "Background"                        },
   { 2, "Spare"                             },
-  { 0, "Best Effort (default)"             },
   { 3, "Excellent Effort"                  },
   { 4, "Controlled Load"                   },
   { 5, "Video, < 100ms latency and jitter" },
@@ -67,19 +85,92 @@ static const value_string pri_vals[] = {
   { 0, NULL                                }
 };
 
+static header_field_info hfi_vlan_priority_old VLAN_HFI_INIT = {
+        "Priority", "vlan.priority", FT_UINT16, BASE_DEC,
+        VALS(pri_vals_old), 0xE000, "Descriptions are recommendations from IEEE standard 802.1D-2004", HFILL };
+
+/* From Table G-2 of IEEE standard 802.1Q-2005 (and I-2 of 2011 and 2014 revisions) */
+/* Note that 0 is still the default, but priority 2 was moved from below 0 to
+ * above it. The new order from lowest to highest is 1,0,2,3,4,5,6,7 */
+static const value_string pri_vals[] = {
+  { 0, "Best Effort (default)"             },
+  { 1, "Background"                        },
+  { 2, "Excellent Effort"                  },
+  { 3, "Critical Applications"             },
+  { 4, "Video, < 100ms latency and jitter" },
+  { 5, "Voice, < 10ms latency and jitter"  },
+  { 6, "Internetwork Control"              },
+  { 7, "Network Control"                   },
+  { 0, NULL                                }
+};
+
 static header_field_info hfi_vlan_priority VLAN_HFI_INIT = {
         "Priority", "vlan.priority", FT_UINT16, BASE_DEC,
-        VALS(pri_vals), 0xE000, "Descriptions are recommendations from IEEE standard 802.1D-2004", HFILL };
+        VALS(pri_vals), 0xE000, "Descriptions are recommendations from IEEE standard 802.1Q-2014", HFILL };
+
+/* From Tables G-2,3 of IEEE standard 802.1Q-2005 (and I-2,3,7 of 2011 and 2014 revisions) */
+static const value_string pri_vals_7[] = {
+  { 0, "Best Effort (default)"                           },
+  { 1, "Background"                                      },
+  { 2, "Excellent Effort"                                },
+  { 3, "Critical Applications"                           },
+  { 4, "Voice, < 10ms latency and jitter, Drop Eligible" },
+  { 5, "Voice, < 10ms latency and jitter"                },
+  { 6, "Internetwork Control"                            },
+  { 7, "Network Control"                                 },
+  { 0, NULL                                              }
+};
 
-static const value_string cfi_vals[] = {
-  { 0, "Canonical"     },
-  { 1, "Non-canonical" },
-  { 0, NULL            }
+static header_field_info hfi_vlan_priority_7 VLAN_HFI_INIT = {
+        "Priority", "vlan.priority", FT_UINT16, BASE_DEC,
+        VALS(pri_vals_7), 0xE000, "Descriptions are recommendations from IEEE standard 802.1Q-2014", HFILL };
+
+/* From Tables G-2,3 of IEEE standard 802.1Q-2005 (and I-2,3,7 of 2011 and 2015 revisions) */
+static const value_string pri_vals_6[] = {
+  { 0, "Best Effort (default)"                            },
+  { 1, "Background"                                       },
+  { 2, "Critical Applications, Drop Eligible"             },
+  { 3, "Critical Applications"                            },
+  { 4, "Voice, < 10ms latency and jitter, Drop Eligible"  },
+  { 5, "Voice, < 10ms latency and jitter"                 },
+  { 6, "Internetwork Control"                             },
+  { 7, "Network Control"                                  },
+  { 0, NULL                                               }
 };
 
+static header_field_info hfi_vlan_priority_6 VLAN_HFI_INIT = {
+        "Priority", "vlan.priority", FT_UINT16, BASE_DEC,
+        VALS(pri_vals_6), 0xE000, "Descriptions are recommendations from IEEE standard 802.1Q-2014", HFILL };
+
+/* From Tables G-2,3 of IEEE standard 802.1Q-2005 (and I-2,3,7 of 2011 and 2015 revisions) */
+static const value_string pri_vals_5[] = {
+  { 0, "Best Effort (default), Drop Eligible"            },
+  { 1, "Best Effort (default)"                           },
+  { 2, "Critical Applications, Drop Eligible"            },
+  { 3, "Critical Applications"                           },
+  { 4, "Voice, < 10ms latency and jitter, Drop Eligible" },
+  { 5, "Voice, < 10ms latency and jitter"                },
+  { 6, "Internetwork Control"                            },
+  { 7, "Network Control"                                 },
+  { 0, NULL                                              }
+};
+
+static header_field_info hfi_vlan_priority_5 VLAN_HFI_INIT = {
+        "Priority", "vlan.priority", FT_UINT16, BASE_DEC,
+        VALS(pri_vals_5), 0xE000, "Descriptions are recommendations from IEEE standard 802.1Q-2014", HFILL };
+
+/* True is non-canonical (i.e., bit-reversed MACs like Token Ring) since usually 0 and canonical. */
+static const true_false_string tfs_noncanonical_canonical = { "Non-canonical", "Canonical" };
+
 static header_field_info hfi_vlan_cfi VLAN_HFI_INIT = {
-        "CFI", "vlan.cfi", FT_UINT16, BASE_DEC,
-        VALS(cfi_vals), 0x1000, "Canonical Format Identifier", HFILL };
+        "CFI", "vlan.cfi", FT_BOOLEAN, 16,
+        TFS(&tfs_noncanonical_canonical), 0x1000, "Canonical Format Identifier", HFILL };
+
+static const true_false_string tfs_eligible_ineligible = { "Eligible", "Ineligible" };
+
+static header_field_info hfi_vlan_dei VLAN_HFI_INIT = {
+        "DEI", "vlan.dei", FT_BOOLEAN, 16,
+        TFS(&tfs_eligible_ineligible), 0x1000, "Drop Eligible Indicator", HFILL };
 
 static header_field_info hfi_vlan_id VLAN_HFI_INIT = {
         "ID", "vlan.id", FT_UINT16, BASE_DEC,
@@ -127,17 +218,19 @@ capture_vlan(const guchar *pd, int offset, int len, capture_packet_info_t *cpinf
 static void
 columns_set_vlan(column_info *cinfo, guint16 tci)
 {
-  static const char fast_str[][2] = { "0", "1", "2", "3", "4", "5", "6", "7" };
-
   char id_str[16];
 
   guint32_to_str_buf(tci & 0xFFF, id_str, sizeof(id_str));
 
-  col_add_lstr(cinfo, COL_INFO,
-               "PRI: ", fast_str[(tci >> 13) & 7], "  "
-               "CFI: ", fast_str[(tci >> 12) & 1], "  "
-                "ID: ", id_str,
-               COL_ADD_LSTR_TERMINATOR);
+  if (vlan_version < IEEE_8021Q_2011) {
+    col_add_fstr(cinfo, COL_INFO,
+                 "PRI: %d  CFI: %d  ID: %s",
+                 (tci >> 13), ((tci >> 12) & 1), id_str);
+  } else {
+    col_add_fstr(cinfo, COL_INFO,
+                 "PRI: %d  DEI: %d  ID: %s",
+                 (tci >> 13), ((tci >> 12) & 1), id_str);
+  }
   col_add_str(cinfo, COL_8021Q_VLAN_ID, id_str);
 }
 
@@ -169,16 +262,46 @@ dissect_vlan(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
     ti = proto_tree_add_item(tree, hfi_vlan, tvb, 0, 4, ENC_NA);
 
     if (vlan_summary_in_tree) {
+      if (vlan_version < IEEE_8021Q_2011) {
         proto_item_append_text(ti, ", PRI: %u, CFI: %u, ID: %u",
                 (tci >> 13), ((tci >> 12) & 1), vlan_id);
+      } else {
+        proto_item_append_text(ti, ", PRI: %u, DEI: %u, ID: %u",
+                (tci >> 13), ((tci >> 12) & 1), vlan_id);
+      }
     }
 
     vlan_tree = proto_item_add_subtree(ti, ett_vlan);
 
-    proto_tree_add_item(vlan_tree, &hfi_vlan_priority, tvb, 0, 2, ENC_BIG_ENDIAN);
-    proto_tree_add_item(vlan_tree, &hfi_vlan_cfi, tvb, 0, 2, ENC_BIG_ENDIAN);
-    proto_tree_add_item(vlan_tree, &hfi_vlan_id, tvb, 0, 2, ENC_BIG_ENDIAN);
+    if (vlan_version == IEEE_8021Q_1998) {
+        proto_tree_add_item(vlan_tree, &hfi_vlan_priority_old, tvb, 0, 2, ENC_BIG_ENDIAN);
+        proto_tree_add_item(vlan_tree, &hfi_vlan_cfi, tvb, 0, 2, ENC_BIG_ENDIAN);
+    } else {
+      switch (vlan_priority_drop) {
+
+        case Priority_Drop_8P0D:
+          proto_tree_add_item(vlan_tree, &hfi_vlan_priority, tvb, 0, 2, ENC_BIG_ENDIAN);
+          break;
 
+        case Priority_Drop_7P1D:
+          proto_tree_add_item(vlan_tree, &hfi_vlan_priority_7, tvb, 0, 2, ENC_BIG_ENDIAN);
+          break;
+
+        case Priority_Drop_6P2D:
+          proto_tree_add_item(vlan_tree, &hfi_vlan_priority_6, tvb, 0, 2, ENC_BIG_ENDIAN);
+          break;
+
+        case Priority_Drop_5P3D:
+          proto_tree_add_item(vlan_tree, &hfi_vlan_priority_5, tvb, 0, 2, ENC_BIG_ENDIAN);
+          break;
+      }
+      if (vlan_version == IEEE_8021Q_2005) {
+        proto_tree_add_item(vlan_tree, &hfi_vlan_cfi, tvb, 0, 2, ENC_BIG_ENDIAN);
+      } else {
+        proto_tree_add_item(vlan_tree, &hfi_vlan_dei, tvb, 0, 2, ENC_BIG_ENDIAN);
+      }
+    }
+    proto_tree_add_item(vlan_tree, &hfi_vlan_id, tvb, 0, 2, ENC_BIG_ENDIAN);
     if (gbl_resolv_flags.vlan_name) {
       item = proto_tree_add_string(vlan_tree, &hfi_vlan_id_name, tvb, 0, 2,
                                    get_vlan_name(wmem_packet_scope(), vlan_id));
@@ -186,6 +309,10 @@ dissect_vlan(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
 
     }
 
+    /* TODO: If the CFI is set on Ethernet (or FDDI MAC and not source routed,
+     * i.e. the RII bit in the source MAC address is 0, then a E-RIF follows.
+     * Only true before version 2011 since the CFI was replaced with DEI
+     * (Since who needs VLANs that bridge Token Ring and FDDI these days?)  */
   }
 
   encap_proto = tvb_get_ntohs(tvb, 2);
@@ -228,8 +355,13 @@ proto_register_vlan(void)
 {
 #ifndef HAVE_HFI_SECTION_INIT
   static header_field_info *hfi[] = {
+    &hfi_vlan_priority_old,
     &hfi_vlan_priority,
+    &hfi_vlan_priority_7,
+    &hfi_vlan_priority_6,
+    &hfi_vlan_priority_5,
     &hfi_vlan_cfi,
+    &hfi_vlan_dei,
     &hfi_vlan_id,
     &hfi_vlan_id_name,
     &hfi_vlan_etype,
@@ -246,6 +378,21 @@ proto_register_vlan(void)
      { &ei_vlan_len, { "vlan.len.past_end", PI_MALFORMED, PI_ERROR, "Length field value goes past the end of the payload", EXPFILL }},
   };
 
+  static const enum_val_t version_vals[] = {
+    {"1998", "IEEE 802.1Q-1998", IEEE_8021Q_1998},
+    {"2005", "IEEE 802.1Q-2005", IEEE_8021Q_2005},
+    {"2011", "IEEE 802.1Q-2011", IEEE_8021Q_2011},
+    {NULL, NULL, -1}
+  };
+
+  static const enum_val_t priority_drop_vals[] = {
+    {"8p0d", "8 Priorities, 0 Drop Eligible", Priority_Drop_8P0D},
+    {"7p1d", "7 Priorities, 1 Drop Eligible", Priority_Drop_7P1D},
+    {"6p2d", "6 Priorities, 2 Drop Eligible", Priority_Drop_6P2D},
+    {"5p3d", "5 Priorities, 3 Drop Eligible", Priority_Drop_5P3D},
+    {NULL, NULL, -1}
+  };
+
   module_t *vlan_module;
   expert_module_t* expert_vlan;
   int proto_vlan;
@@ -267,7 +414,14 @@ proto_register_vlan(void)
         "802.1QinQ Ethertype (in hex)",
         "The (hexadecimal) Ethertype used to indicate 802.1QinQ VLAN in VLAN tunneling.",
         16, &q_in_q_ethertype);
-
+  prefs_register_enum_preference(vlan_module, "version",
+        "IEEE 802.1Q version",
+        "IEEE 802.1Q specification version used (802.1Q-1998 uses 802.1D-2004 for PRI values)",
+        &vlan_version, version_vals, TRUE);
+  prefs_register_enum_preference(vlan_module, "priority_drop",
+        "Priorities and drop eligibility",
+        "Number of priorities supported, and number of those drop eligible (not used for 802.1Q-1998)",
+        &vlan_priority_drop, priority_drop_vals, TRUE);
   vlan_handle = create_dissector_handle(dissect_vlan, proto_vlan);
 }