Add subdissector table for MPLS PW Associated Channel Type

Change-Id: Id72fcbe74b91b4eb25fb4d3f3d47a1d53c2857b2
Reviewed-on: https://code.wireshark.org/review/5212
Reviewed-by: Michael Mann <mmann78@netscape.net>

10 files changed, 74 insertions, 121 deletions

diff --git a/epan/dissectors/packet-bfd.c b/epan/dissectors/packet-bfd.c
index ba71fa7bf7..379c314762 100644
--- a/epan/dissectors/packet-bfd.c
+++ b/epan/dissectors/packet-bfd.c
@@ -40,6 +40,7 @@
 #include <epan/expert.h>
 
 #include "packet-bfd.h"
+#include "packet-mpls.h"
 
 void proto_register_bfd(void);
 void proto_reg_handoff_bfd(void);
@@ -923,6 +924,10 @@ proto_reg_handoff_bfd(void)
     bfd_control_handle = find_dissector("bfd");
     dissector_add_uint("udp.port", UDP_PORT_BFD_1HOP_CONTROL,     bfd_control_handle);
     dissector_add_uint("udp.port", UDP_PORT_BFD_MULTIHOP_CONTROL, bfd_control_handle);
+
+    dissector_add_uint("pwach.channel_type", ACH_TYPE_BFD_CC, bfd_control_handle);
+    dissector_add_uint("pwach.channel_type", ACH_TYPE_BFD_CV, bfd_control_handle);
+    dissector_add_uint("pwach.channel_type", 0x7, bfd_control_handle); /* PWACH-encapsulated BFD, RFC 5885 */
 }
 
 /*
diff --git a/epan/dissectors/packet-ip.c b/epan/dissectors/packet-ip.c
index a1f8dec434..3dd2dfcc07 100644
--- a/epan/dissectors/packet-ip.c
+++ b/epan/dissectors/packet-ip.c
@@ -3106,6 +3106,7 @@ proto_reg_handoff_ip(void)
   dissector_add_uint("ax25.pid", AX25_P_IP, ip_handle);
   dissector_add_uint("juniper.proto", JUNIPER_PROTO_IP, ip_handle);
   dissector_add_uint("juniper.proto", JUNIPER_PROTO_MPLS_IP, ip_handle);
+  dissector_add_uint("pwach.channel_type", 0x21, ip_handle); /* IPv4, RFC4385 clause 6. */
   dissector_add_for_decode_as("udp.port", ip_handle);
 
   heur_dissector_add("tipc", dissect_ip_heur, proto_ip);
diff --git a/epan/dissectors/packet-ipv6.c b/epan/dissectors/packet-ipv6.c
index 9de8c8fb80..ee7b0319b6 100644
--- a/epan/dissectors/packet-ipv6.c
+++ b/epan/dissectors/packet-ipv6.c
@@ -3040,6 +3040,7 @@ proto_reg_handoff_ipv6(void)
     dissector_add_uint("arcnet.protocol_id", ARCNET_PROTO_IPv6, ipv6_handle);
     dissector_add_uint("juniper.proto", JUNIPER_PROTO_IP6, ipv6_handle);
     dissector_add_uint("juniper.proto", JUNIPER_PROTO_MPLS_IP6, ipv6_handle);
+    dissector_add_uint("pwach.channel_type", 0x57, ipv6_handle); /* IPv6, RFC4385 clause 6. */
 
     ipv6_hopopts_handle = new_create_dissector_handle(dissect_hopopts, proto_ipv6_hopopts );
     dissector_add_uint("ipv6.nxt", IP_PROTO_HOPOPTS, ipv6_hopopts_handle);
diff --git a/epan/dissectors/packet-mpls-echo.c b/epan/dissectors/packet-mpls-echo.c
index b499549ad7..a1a6a8e15b 100644
--- a/epan/dissectors/packet-mpls-echo.c
+++ b/epan/dissectors/packet-mpls-echo.c
@@ -2564,6 +2564,8 @@ proto_reg_handoff_mpls_echo(void)
 
     mpls_echo_udp_port = global_mpls_echo_udp_port;
     dissector_add_uint("udp.port", global_mpls_echo_udp_port, mpls_echo_handle);
+
+    dissector_add_uint("pwach.channel_type", ACH_TYPE_ONDEMAND_CV, mpls_echo_handle);
 }
 
 /*
diff --git a/epan/dissectors/packet-mpls-pm.c b/epan/dissectors/packet-mpls-pm.c
index 3cfad17939..e149d92c2d 100644
--- a/epan/dissectors/packet-mpls-pm.c
+++ b/epan/dissectors/packet-mpls-pm.c
@@ -111,12 +111,6 @@ static int hf_mpls_pm_timestamp4_r_ntp = -1;
 static int hf_mpls_pm_timestamp4_r_ptp = -1;
 static int hf_mpls_pm_timestamp4_unk = -1;
 
-static dissector_handle_t mpls_pm_dlm_handle;
-static dissector_handle_t mpls_pm_ilm_handle;
-static dissector_handle_t mpls_pm_dm_handle;
-static dissector_handle_t mpls_pm_dlm_dm_handle;
-static dissector_handle_t mpls_pm_ilm_dm_handle;
-
 /*
  * FF: please keep this list in sync with
  * http://www.iana.org/assignments/mpls-lsp-ping-parameters
@@ -1383,31 +1377,25 @@ proto_register_mpls_pm(void)
 
     proto_register_field_array(proto_mpls_pm_dlm, hf, array_length(hf));
     proto_register_subtree_array(ett, array_length(ett));
-
-    register_dissector("mpls_pm_dlm", dissect_mpls_pm_dlm,
-                       proto_mpls_pm_dlm);
-
-    register_dissector("mpls_pm_ilm", dissect_mpls_pm_ilm,
-                       proto_mpls_pm_ilm);
-
-    register_dissector("mpls_pm_dm", dissect_mpls_pm_delay,
-                       proto_mpls_pm_dm);
-
-    register_dissector("mpls_pm_dlm_dm", dissect_mpls_pm_dlm_dm,
-                       proto_mpls_pm_dlm_dm);
-
-    register_dissector("mpls_pm_ilm_dm", dissect_mpls_pm_ilm_dm,
-                       proto_mpls_pm_ilm_dm);
 }
 
 void
 proto_reg_handoff_mpls_pm(void)
 {
-    mpls_pm_dlm_handle    = find_dissector("mpls_pm_dlm");
-    mpls_pm_ilm_handle    = find_dissector("mpls_pm_ilm");
-    mpls_pm_dm_handle     = find_dissector("mpls_pm_dm");
-    mpls_pm_dlm_dm_handle = find_dissector("mpls_pm_dlm_dm");
-    mpls_pm_ilm_dm_handle = find_dissector("mpls_pm_ilm_dm");
+    dissector_handle_t mpls_pm_dlm_handle, mpls_pm_ilm_handle, mpls_pm_dm_handle,
+                       mpls_pm_dlm_dm_handle, mpls_pm_ilm_dm_handle;
+
+    mpls_pm_dlm_handle    = create_dissector_handle( dissect_mpls_pm_dlm, proto_mpls_pm_dlm );
+    dissector_add_uint("pwach.channel_type", 0x000A, mpls_pm_dlm_handle); /* FF: MPLS PM, RFC 6374, DLM */
+    mpls_pm_ilm_handle    = create_dissector_handle( dissect_mpls_pm_ilm, proto_mpls_pm_ilm );
+    dissector_add_uint("pwach.channel_type", 0x000B, mpls_pm_ilm_handle); /* FF: MPLS PM, RFC 6374, ILM */
+    mpls_pm_dm_handle    = create_dissector_handle( dissect_mpls_pm_delay, proto_mpls_pm_dm );
+    dissector_add_uint("pwach.channel_type", 0x000C, mpls_pm_dm_handle); /* FF: MPLS PM, RFC 6374, DM */
+    mpls_pm_dlm_dm_handle    = create_dissector_handle( dissect_mpls_pm_dlm_dm, proto_mpls_pm_dlm_dm );
+    dissector_add_uint("pwach.channel_type", 0x000D, mpls_pm_dlm_dm_handle); /* FF: MPLS PM, RFC 6374, DLM+DM */
+    mpls_pm_ilm_dm_handle    = create_dissector_handle( dissect_mpls_pm_ilm_dm, proto_mpls_pm_ilm_dm );
+    dissector_add_uint("pwach.channel_type", 0x000E, mpls_pm_ilm_dm_handle); /* FF: MPLS PM, RFC 6374, ILM+DM */
+
 }
 
 /*
diff --git a/epan/dissectors/packet-mpls-psc.c b/epan/dissectors/packet-mpls-psc.c
index fe5da0b994..2f43c61a3e 100644
--- a/epan/dissectors/packet-mpls-psc.c
+++ b/epan/dissectors/packet-mpls-psc.c
@@ -234,8 +234,15 @@ proto_register_mpls_psc(void)
 
     proto_register_field_array(proto_mpls_psc, hf, array_length(hf));
     proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_mpls_psc(void)
+{
+	dissector_handle_t mpls_psc_handle;
 
-    register_dissector("mpls_psc", dissect_mpls_psc, proto_mpls_psc);
+    mpls_psc_handle    = create_dissector_handle( dissect_mpls_psc, proto_mpls_psc );
+    dissector_add_uint("pwach.channel_type", 0x0024, mpls_psc_handle); /* FF: PSC, RFC 6378 */
 }
 
 /*
diff --git a/epan/dissectors/packet-mpls.c b/epan/dissectors/packet-mpls.c
index 51b3190d0c..442718b2e1 100644
--- a/epan/dissectors/packet-mpls.c
+++ b/epan/dissectors/packet-mpls.c
@@ -68,12 +68,6 @@
 void proto_register_mpls(void);
 void proto_reg_handoff_mpls(void);
 
-/* As per RFC 6428 http://tools.ietf.org/html/rfc6428, Section: 3.3 */
-#define ACH_TYPE_BFD_CC               0x0022
-#define ACH_TYPE_BFD_CV               0x0023
-/* As RFC 6426:http://tools.ietf.org/html/rfc6426, Section: 7.4 */
-#define ACH_TYPE_ONDEMAND_CV          0x0025
-
 static gint proto_mpls = -1;
 static gint proto_pw_ach = -1;
 static gint proto_pw_mcw = -1;
@@ -93,19 +87,11 @@ const value_string special_labels[] = {
     {0, NULL }
 };
 
+static dissector_table_t   pw_ach_subdissector_table;
+
 static dissector_handle_t dissector_data;
 static dissector_handle_t dissector_ipv6;
 static dissector_handle_t dissector_ip;
-static dissector_handle_t dissector_bfd;
-static dissector_handle_t dissector_mpls_pm_dlm;
-static dissector_handle_t dissector_mpls_pm_ilm;
-static dissector_handle_t dissector_mpls_pm_dm;
-static dissector_handle_t dissector_mpls_pm_dlm_dm;
-static dissector_handle_t dissector_mpls_pm_ilm_dm;
-static dissector_handle_t dissector_mpls_psc;
-static dissector_handle_t dissector_mplstp_lock;
-static dissector_handle_t dissector_mplstp_fm;
-static dissector_handle_t dissector_pw_oam;
 static dissector_handle_t dissector_pw_eth_heuristic;
 static dissector_handle_t dissector_pw_fr;
 static dissector_handle_t dissector_pw_hdlc_nocw_fr;
@@ -397,71 +383,16 @@ dissect_pw_ach(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 
     next_tvb     = tvb_new_subset_remaining(tvb, 4);
 
-    switch (channel_type) {
-        case ACH_TYPE_BFD_CC:
-            call_dissector(dissector_bfd, next_tvb, pinfo, tree);  /* bfd_control() */
-            break;
-
-        case ACH_TYPE_BFD_CV:
-            call_dissector(dissector_bfd, next_tvb, pinfo, tree);  /* bfd_control() */
-            dissect_bfd_mep(next_tvb, tree, 0);
-            break;
-
-        case ACH_TYPE_ONDEMAND_CV:
-            dissect_mpls_echo(next_tvb, pinfo, tree, NULL);
-            break;
-
-        case 0x21:   /* IPv4, RFC4385 clause 6. */
-            call_dissector(dissector_ip, next_tvb, pinfo, tree);
-            break;
-
-        case 0x7:    /* PWACH-encapsulated BFD, RFC 5885 */
-            call_dissector(dissector_bfd, next_tvb, pinfo, tree);
-            break;
+	if (!dissector_try_uint(pw_ach_subdissector_table, channel_type, next_tvb, pinfo, tree))
+	{
+        call_dissector(dissector_data, next_tvb, pinfo, tree);
+	}
 
-        case 0x57:   /* IPv6, RFC4385 clause 6. */
-            call_dissector(dissector_ipv6, next_tvb, pinfo, tree);
-            break;
-
-        case 0x000A: /* FF: MPLS PM, RFC 6374, DLM */
-            call_dissector(dissector_mpls_pm_dlm, next_tvb, pinfo, tree);
-            break;
-
-        case 0x000B: /* FF: MPLS PM, RFC 6374, ILM */
-            call_dissector(dissector_mpls_pm_ilm, next_tvb, pinfo, tree);
-            break;
-
-        case 0x000C: /* FF: MPLS PM, RFC 6374, DM */
-            call_dissector(dissector_mpls_pm_dm, next_tvb, pinfo, tree);
-            break;
-
-        case 0x000D: /* FF: MPLS PM, RFC 6374, DLM+DM */
-            call_dissector(dissector_mpls_pm_dlm_dm, next_tvb, pinfo, tree);
-            break;
-
-        case 0x000E: /* FF: MPLS PM, RFC 6374, ILM+DM */
-            call_dissector(dissector_mpls_pm_ilm_dm, next_tvb, pinfo, tree);
-            break;
-
-        case 0x0024: /* FF: PSC, RFC 6378 */
-            call_dissector(dissector_mpls_psc, next_tvb, pinfo, tree);
-            break;
-
-        case 0x0026: /* KM: MPLSTP LOCK, RFC 6435 */
-            call_dissector(dissector_mplstp_lock, next_tvb, pinfo, tree);
-            break;
-
-        case 0x0027: /* KM: MPLSTP PW-OAM, RFC 6478 */
-            call_dissector(dissector_pw_oam, next_tvb, pinfo, tree);
-            break;
-
-        case 0x0058: /* KM: MPLSTP FM, RFC 6427 */
-            call_dissector(dissector_mplstp_fm, next_tvb, pinfo, tree);
-            break;
-
-        default:
-            call_dissector(dissector_data, next_tvb, pinfo, tree);
-            break;
+    if (channel_type == ACH_TYPE_BFD_CV)
+    {
+        /* The BFD dissector has already been called, this is called in addition
+           XXX - Perhaps a new dissector function that combines both is preferred.*/
+        dissect_bfd_mep(next_tvb, tree, 0);
     }
 }
 
@@ -799,6 +730,8 @@ proto_register_mpls(void)
     register_dissector("mpls", dissect_mpls, proto_mpls);
     register_dissector("mplspwcw", dissect_pw_mcw, proto_pw_mcw );
 
+    pw_ach_subdissector_table  = register_dissector_table("pwach.channel_type", "PW Associated Channel Type", FT_UINT16, BASE_HEX);
+
     module_mpls = prefs_register_protocol( proto_mpls, NULL );
 
     prefs_register_enum_preference(module_mpls,
@@ -845,16 +778,6 @@ proto_reg_handoff_mpls(void)
     dissector_data                  = find_dissector("data");
     dissector_ipv6                  = find_dissector("ipv6");
     dissector_ip                    = find_dissector("ip");
-    dissector_bfd                   = find_dissector("bfd");
-    dissector_mpls_pm_dlm           = find_dissector("mpls_pm_dlm");
-    dissector_mpls_pm_ilm           = find_dissector("mpls_pm_ilm");
-    dissector_mpls_pm_dm            = find_dissector("mpls_pm_dm");
-    dissector_mpls_pm_dlm_dm        = find_dissector("mpls_pm_dlm_dm");
-    dissector_mpls_pm_ilm_dm        = find_dissector("mpls_pm_ilm_dm");
-    dissector_mpls_psc              = find_dissector("mpls_psc");
-    dissector_mplstp_lock           = find_dissector("mplstp_lock");
-    dissector_mplstp_fm             = find_dissector("mplstp_fm");
-    dissector_pw_oam                = find_dissector("pw_oam");
     dissector_pw_eth_heuristic      = find_dissector("pw_eth_heuristic");
     dissector_pw_fr                 = find_dissector("pw_fr");
     dissector_pw_hdlc_nocw_fr       = find_dissector("pw_hdlc_nocw_fr");
diff --git a/epan/dissectors/packet-mpls.h b/epan/dissectors/packet-mpls.h
index 1186a02ec7..800f4ad8fa 100644
--- a/epan/dissectors/packet-mpls.h
+++ b/epan/dissectors/packet-mpls.h
@@ -42,6 +42,12 @@ enum {
     MPLS_LABEL_INVALID           = -1
 };
 
+/* As per RFC 6428 http://tools.ietf.org/html/rfc6428, Section: 3.3 */
+#define ACH_TYPE_BFD_CC               0x0022
+#define ACH_TYPE_BFD_CV               0x0023
+/* As RFC 6426:http://tools.ietf.org/html/rfc6426, Section: 7.4 */
+#define ACH_TYPE_ONDEMAND_CV          0x0025
+
 /*
  * FF: private data passed from the MPLS dissector to subdissectors
  * (data parameter).
@@ -60,6 +66,5 @@ extern void decode_mpls_label(tvbuff_t *tvb, int offset,
 
 extern gboolean dissect_try_cw_first_nibble(tvbuff_t *tvb, packet_info *pinfo,
                                             proto_tree *tree );
-int dissect_mpls_echo(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_);
 
 #endif
diff --git a/epan/dissectors/packet-mplstp-oam.c b/epan/dissectors/packet-mplstp-oam.c
index 3174c19be1..25f2902e7c 100644
--- a/epan/dissectors/packet-mplstp-oam.c
+++ b/epan/dissectors/packet-mplstp-oam.c
@@ -247,8 +247,15 @@ proto_register_mplstp_lock(void)
 
   proto_register_field_array(proto_mplstp_lock, hf, array_length(hf));
   proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_mplstp_lock(void)
+{
+  dissector_handle_t mplstp_lock_handle;
 
-  register_dissector("mplstp_lock", dissect_mplstp_lock, proto_mplstp_lock);
+  mplstp_lock_handle    = create_dissector_handle( dissect_mplstp_lock, proto_mplstp_lock );
+  dissector_add_uint("pwach.channel_type", 0x0026, mplstp_lock_handle); /* KM: MPLSTP LOCK, RFC 6435 */
 }
 
 void
@@ -329,8 +336,15 @@ proto_register_mplstp_fm(void)
 
   proto_register_field_array(proto_mplstp_fm, hf, array_length(hf));
   proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_mplstp_fm(void)
+{
+  dissector_handle_t mplstp_fm_handle;
 
-  register_dissector("mplstp_fm", dissect_mplstp_fm, proto_mplstp_fm);
+  mplstp_fm_handle = create_dissector_handle( dissect_mplstp_fm, proto_mplstp_fm );
+  dissector_add_uint("pwach.channel_type", 0x0058, mplstp_fm_handle); /* KM: MPLSTP FM, RFC 6427 */
 }
 
 /*
diff --git a/epan/dissectors/packet-pw-oam.c b/epan/dissectors/packet-pw-oam.c
index 7bc29bbe98..b683e2ed98 100644
--- a/epan/dissectors/packet-pw-oam.c
+++ b/epan/dissectors/packet-pw-oam.c
@@ -200,8 +200,15 @@ proto_register_pw_oam(void)
 
   proto_register_field_array (proto_pw_oam, hf, array_length(hf));
   proto_register_subtree_array (ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_pw_oam(void)
+{
+  dissector_handle_t pw_oam_handle;
 
-  register_dissector("pw_oam", dissect_pw_oam, proto_pw_oam);
+  pw_oam_handle = create_dissector_handle( dissect_pw_oam, proto_pw_oam );
+  dissector_add_uint("pwach.channel_type", 0x0027, pw_oam_handle); /* KM: MPLSTP PW-OAM, RFC 6478 */
 }
 
 /*