Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 463 insertions, 0 deletions

diff --git a/epan/dissectors/packet-pw-cesopsn.c b/epan/dissectors/packet-pw-cesopsn.c
new file mode 100644
index 00000000..b5f58ae8
--- /dev/null
+++ b/epan/dissectors/packet-pw-cesopsn.c
@@ -0,0 +1,463 @@
+/* packet-pw-satop.c
+ * Routines for CESoPSN PW dissection as per RFC5086.
+ * Copyright 2009, Dmitry Trebich, Artem Tamazov <artem.tamazov@tellabs.com>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * History:
+ * ---------------------------------
+ * 16.03.2009 initial implementation for MPLS
+ * 14.08.2009 added: support for IP/UDP demultiplexing
+ * Not supported yet:
+ * - All PW modes, except Basic NxDS0 mode.
+ * - <Optional> RTP Headers (RFC3550)
+ * - Decoding of PW payload
+ */
+
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/expert.h>
+
+#include "packet-mpls.h"
+#include "packet-pw-common.h"
+
+void proto_register_pw_cesopsn(void);
+void proto_reg_handoff_pw_cesopsn(void);
+
+static gint proto = -1;
+static gint ett_pw_cesopsn = -1;
+
+static int hf_cw = -1;
+static int hf_cw_bits03 = -1;
+static int hf_cw_lm = -1;
+static int hf_cw_r = -1;
+static int hf_cw_frg = -1;
+static int hf_cw_len = -1;
+static int hf_cw_seq = -1;
+static int hf_payload = -1;
+static int hf_payload_l = -1;
+
+static expert_field ei_payload_size_invalid_undecoded = EI_INIT;
+static expert_field ei_cw_frg = EI_INIT;
+static expert_field ei_payload_size_invalid_error = EI_INIT;
+static expert_field ei_cw_bits03 = EI_INIT;
+static expert_field ei_pref_cw_len = EI_INIT;
+static expert_field ei_cw_lm = EI_INIT;
+static expert_field ei_packet_size_too_small = EI_INIT;
+
+static dissector_handle_t pw_padding_handle;
+static dissector_handle_t pw_cesopsn_udp_handle;
+static dissector_handle_t pw_cesopsn_mpls_handle;
+
+
+const char pwc_longname_pw_cesopsn[] = "CESoPSN basic NxDS0 mode (no RTP support)";
+static const char shortname[] = "CESoPSN basic (no RTP)";
+
+static const value_string vals_cw_lm[] = {
+	/* note that bitmask in hs_register_info is 0xb == 1011B */
+	/* this is why 0x8 comes just after 0x3 */
+	{ 0x0,	"Normal situation - no AC faults" },
+	/*{ 0x1,	"Reserved combination" },*/
+	{ 0x2,	"AC Fault - RDI condition" },
+	{ 0x3,	"Reserved for CESoPSN signaling" },
+	{ 0x8,	"AC Fault - TDM data is invalid" },
+	/*{ 0x9,	"Reserved combination" },*/
+	/*{ 0xa,	"Reserved combination" },*/
+	/*{ 0xb,	"Reserved combination" },*/
+	{ 0,	NULL }
+};
+
+
+static
+void dissect_pw_cesopsn( tvbuff_t * tvb_original
+						,packet_info * pinfo
+						,proto_tree * tree
+						,pwc_demux_type_t demux)
+{
+	const int encaps_size = 4; /*RTP header in encapsulation is not supported yet*/
+	gint      packet_size;
+	gint      payload_size;
+	gint      padding_size;
+	int properties;
+
+	packet_size = tvb_reported_length_remaining(tvb_original, 0);
+
+	/*
+	 * FIXME
+	 * "4" below should be replaced by something like "min_packet_size_this_dissector"
+	 * Also call to dissect_try_cw_first_nibble() should be moved before this block
+	 */
+	if (packet_size < 4) /* 4 is smallest size which may be sensible (for PWACH dissector) */
+	{
+		proto_item  *item;
+		item = proto_tree_add_item(tree, proto, tvb_original, 0, -1, ENC_NA);
+		expert_add_info_format(pinfo, item, &ei_packet_size_too_small,
+				       "PW packet size (%d) is too small to carry sensible information"
+				       ,(int)packet_size);
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, shortname);
+		col_set_str(pinfo->cinfo, COL_INFO, "Malformed: PW packet is too small");
+		return;
+	}
+
+	switch (demux)
+	{
+	case PWC_DEMUX_MPLS:
+		if (dissect_try_cw_first_nibble(tvb_original, pinfo, tree))
+		{
+			return;
+		}
+		break;
+	case PWC_DEMUX_UDP:
+		break;
+	default:
+		DISSECTOR_ASSERT_NOT_REACHED();
+		return;
+	}
+
+	/* check how "good" is this packet */
+	/* also decide payload length from packet size and CW */
+	properties = PWC_PACKET_PROPERTIES_T_INITIALIZER;
+	if (0 != (tvb_get_guint8(tvb_original, 0) & 0xf0 /*bits03*/))
+	{
+		properties |= PWC_CW_BAD_BITS03;
+	}
+	if (0 != (tvb_get_guint8(tvb_original, 1) & 0xc0 /*frag*/))
+	{
+		properties |= PWC_CW_BAD_FRAG;
+	}
+	{
+		/* RFC5086:
+		 * [LEN (bits (10 to 15) MAY be used to carry the length of the CESoPSN
+		 * packet (defined as the size of the CESoPSN header + the payload size)
+		 * if it is less than 64 bytes, and MUST be set to zero otherwise.
+		 * Note:  If fixed RTP header is used in the encapsulation, it is
+		 * considered part of the CESoPSN header.]
+		 *
+		 * Note that this differs from RFC4385's definition of length:
+		 * [ If the MPLS payload is less than 64 bytes, the length field
+		 * MUST be set to the length of the PW payload...]
+		 *
+		 * We will use RFC5086's definition here.
+		 */
+		int  cw_len;
+		gint payload_size_from_packet;
+
+		cw_len = tvb_get_guint8(tvb_original, 1) & 0x3f;
+		payload_size_from_packet = packet_size - encaps_size;
+		if (cw_len != 0)
+		{
+			gint payload_size_from_cw;
+			payload_size_from_cw = cw_len - encaps_size;
+			/*
+			 * Assumptions for error case,
+			 * will be overwritten if no errors found:
+			 */
+			payload_size = payload_size_from_packet;
+			padding_size = 0;
+
+			if (payload_size_from_cw < 0)
+			{
+				properties |= PWC_CW_BAD_PAYLEN_LT_0;
+			}
+			else if (payload_size_from_cw > payload_size_from_packet)
+			{
+				properties |= PWC_CW_BAD_PAYLEN_GT_PACKET;
+			}
+			else if (payload_size_from_packet >= 64)
+			{
+				properties |= PWC_CW_BAD_LEN_MUST_BE_0;
+			}
+			else /* ok */
+			{
+				payload_size = payload_size_from_cw;
+				padding_size = payload_size_from_packet - payload_size_from_cw; /* >=0 */
+			}
+		}
+		else
+		{
+			payload_size = payload_size_from_packet;
+			padding_size = 0;
+		}
+	}
+
+	{
+		guint8 cw_lm;
+		cw_lm = tvb_get_guint8(tvb_original, 0) & 0x0b /*l+mod*/;
+		if (NULL == try_val_to_str(cw_lm, vals_cw_lm))
+		{
+			properties |= PWC_CW_SUSPECT_LM;
+		}
+
+		{
+			guint8 l_bit, m_bits;
+			l_bit  = (cw_lm & 0x08) >> 3;
+			m_bits = (cw_lm & 0x03) >> 0;
+			if ((l_bit == 0 && m_bits == 0x0) /*CESoPSN data packet - normal situation*/
+			    ||(l_bit == 0 && m_bits == 0x2) /*CESoPSN data packet - RDI on the AC*/ )
+			{
+				if ((payload_size == 0) || ((payload_size % 8) != 0))
+				{
+					properties |= PWC_PAY_SIZE_BAD;
+				}
+			}
+			else if (l_bit == 1 && m_bits == 0x0) /*TDM data is invalid; payload MAY be omitted*/
+			{
+				/*allow any size of payload*/
+			}
+			else /*reserved combinations*/
+			{
+				/*allow any size of payload*/
+			}
+		}
+	}
+
+	/* fill up columns*/
+	col_set_str(pinfo->cinfo, COL_PROTOCOL, shortname);
+	col_clear(pinfo->cinfo, COL_INFO);
+	if (properties & PWC_ANYOF_CW_BAD)
+	{
+		col_set_str(pinfo->cinfo, COL_INFO, "CW:Bad, ");
+	}
+	else if (properties & PWC_ANYOF_CW_SUSPECT)
+	{
+		col_append_str(pinfo->cinfo, COL_INFO, "CW:Suspect, ");
+	}
+
+	if (properties & PWC_PAY_SIZE_BAD)
+	{
+		col_append_str(pinfo->cinfo, COL_INFO, "Payload size:Bad, ");
+	}
+
+	col_append_fstr(pinfo->cinfo, COL_INFO, "TDM octets:%d", (int)payload_size);
+
+	if (padding_size != 0)
+	{
+		col_append_fstr(pinfo->cinfo, COL_INFO, ", Padding:%d", (int)padding_size);
+	}
+
+	{
+		proto_item* item;
+		item = proto_tree_add_item(tree, proto, tvb_original, 0, -1, ENC_NA);
+		pwc_item_append_cw(item,tvb_get_ntohl(tvb_original, 0),TRUE);
+		pwc_item_append_text_n_items(item,(int)payload_size,"octet");
+		{
+			proto_tree* tree2;
+			tree2 = proto_item_add_subtree(item, ett_pw_cesopsn);
+			{
+				tvbuff_t* tvb;
+				proto_item* item2;
+				tvb = tvb_new_subset_length(tvb_original, 0, PWC_SIZEOF_CW);
+				item2 = proto_tree_add_item(tree2, hf_cw, tvb, 0, -1, ENC_NA);
+				pwc_item_append_cw(item2,tvb_get_ntohl(tvb, 0),FALSE);
+				{
+					proto_tree* tree3;
+					tree3 = proto_item_add_subtree(item, ett_pw_cesopsn);
+					{
+						proto_item* item3;
+						if (properties & PWC_CW_BAD_BITS03) /*display only if value is wrong*/
+						{
+							item3 = proto_tree_add_item(tree3, hf_cw_bits03, tvb, 0, 1, ENC_BIG_ENDIAN);
+							expert_add_info(pinfo, item3, &ei_cw_bits03);
+						}
+
+						item3 = proto_tree_add_item(tree3, hf_cw_lm,  tvb, 0, 1, ENC_BIG_ENDIAN);
+						if (properties & PWC_CW_SUSPECT_LM)
+						{
+							expert_add_info(pinfo, item3, &ei_cw_lm);
+						}
+
+						proto_tree_add_item(tree3, hf_cw_r, tvb, 0, 1, ENC_BIG_ENDIAN);
+
+						item3 = proto_tree_add_item(tree3, hf_cw_frg, tvb, 1, 1, ENC_BIG_ENDIAN);
+						if (properties & PWC_CW_BAD_FRAG)
+						{
+							expert_add_info(pinfo, item3, &ei_cw_frg);
+						}
+
+						item3 = proto_tree_add_item(tree3, hf_cw_len, tvb, 1, 1, ENC_BIG_ENDIAN);
+						if (properties & PWC_CW_BAD_PAYLEN_LT_0)
+						{
+							expert_add_info_format(pinfo, item3, &ei_pref_cw_len,
+								"Bad Length: too small, must be > %d",
+								(int)encaps_size);
+						}
+						if (properties & PWC_CW_BAD_PAYLEN_GT_PACKET)
+						{
+							expert_add_info_format(pinfo, item3, &ei_pref_cw_len,
+								"Bad Length: must be <= than PSN packet size (%d)",
+								(int)packet_size);
+						}
+						if (properties & PWC_CW_BAD_LEN_MUST_BE_0)
+						{
+							expert_add_info_format(pinfo, item3, &ei_pref_cw_len,
+								"Bad Length: must be 0 if CESoPSN packet size (%d) is > 64",
+								(int)packet_size);
+						}
+
+						proto_tree_add_item(tree3, hf_cw_seq, tvb, 2, 2, ENC_BIG_ENDIAN);
+
+					}
+				}
+			}
+		}
+
+		/* payload */
+		if (payload_size == 0)
+		{
+			if (properties & PWC_PAY_SIZE_BAD)
+			{
+				expert_add_info_format(pinfo, item, &ei_payload_size_invalid_error,
+					"CESoPSN payload: none found. Size of payload must be <> 0");
+			}
+			else
+			{
+				expert_add_info_format(pinfo, item, &ei_payload_size_invalid_undecoded,
+					"CESoPSN payload: omitted to conserve bandwidth");
+			}
+		}
+		else
+		{
+			proto_tree* tree2;
+			tree2 = proto_item_add_subtree(item, ett_pw_cesopsn);
+			{
+				proto_item* item2;
+				tvbuff_t* tvb;
+				tvb = tvb_new_subset_length(tvb_original, PWC_SIZEOF_CW, payload_size);
+				item2 = proto_tree_add_item(tree2, hf_payload, tvb, 0, -1, ENC_NA);
+				pwc_item_append_text_n_items(item2,(int)payload_size,"octet");
+				if (properties & PWC_PAY_SIZE_BAD)
+				{
+					expert_add_info_format(pinfo, item2, &ei_payload_size_invalid_error,
+						"CESoPSN packet payload size must be multiple of 8");
+				}
+				tree2 = proto_item_add_subtree(item2, ett_pw_cesopsn);
+				call_data_dissector(tvb, pinfo, tree2);
+				item2 = proto_tree_add_int(tree2, hf_payload_l, tvb, 0, 0
+					,(int)payload_size); /* allow filtering */
+				proto_item_set_hidden(item2);
+			}
+		}
+
+		/* padding */
+		if (padding_size > 0)
+		{
+			proto_tree* tree2;
+			tree2 = proto_item_add_subtree(item, ett_pw_cesopsn);
+			{
+				tvbuff_t* tvb;
+				tvb = tvb_new_subset_length_caplen(tvb_original, PWC_SIZEOF_CW + payload_size, padding_size, -1);
+				call_dissector(pw_padding_handle, tvb, pinfo, tree2);
+			}
+		}
+	}
+	return;
+}
+
+
+static
+int dissect_pw_cesopsn_mpls( tvbuff_t * tvb_original, packet_info * pinfo, proto_tree * tree, void* data _U_)
+{
+	dissect_pw_cesopsn(tvb_original,pinfo,tree,PWC_DEMUX_MPLS);
+	return tvb_captured_length(tvb_original);
+}
+
+
+static
+int dissect_pw_cesopsn_udp( tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree, void* data _U_)
+{
+	dissect_pw_cesopsn(tvb,pinfo,tree,PWC_DEMUX_UDP);
+	return tvb_captured_length(tvb);
+}
+
+
+void proto_register_pw_cesopsn(void)
+{
+	static hf_register_info hf[] = {
+		{ &hf_cw	,{"Control Word"		,"pwcesopsn.cw"
+				  ,FT_NONE			,BASE_NONE		,NULL
+				  ,0				,NULL			,HFILL }},
+
+		{&hf_cw_bits03,{"Bits 0 to 3"			,"pwcesopsn.cw.bits03"
+				,FT_UINT8			,BASE_DEC		,NULL
+				,0xf0				,NULL			,HFILL }},
+
+		{ &hf_cw_lm, 	{"L+M bits"			,"pwcesopsn.cw.lm"
+				 ,FT_UINT8			,BASE_HEX		,VALS(vals_cw_lm)
+				 ,0x0b	  			,NULL 			,HFILL }},
+
+		{&hf_cw_r,	{"R bit: Local CE-bound IWF"	,"pwcesopsn.cw.rbit"
+				 ,FT_UINT8			,BASE_DEC		,VALS(pwc_vals_cw_r_bit)
+				 ,0x04				,NULL			,HFILL }},
+
+		{&hf_cw_frg,	{"Fragmentation"		,"pwcesopsn.cw.frag"
+				 ,FT_UINT8			,BASE_DEC		,VALS(pwc_vals_cw_frag)
+				 ,0xc0				,NULL			,HFILL }},
+
+		{&hf_cw_len,	{"Length"			,"pwcesopsn.cw.length"
+				 ,FT_UINT8			,BASE_DEC		,NULL
+				 ,0x3f				,NULL			,HFILL }},
+
+		{&hf_cw_seq,	{"Sequence number"		,"pwcesopsn.cw.seqno"
+				 ,FT_UINT16			,BASE_DEC		,NULL
+				 ,0				,NULL			,HFILL }},
+
+		{&hf_payload	,{"TDM payload"			,"pwcesopsn.payload"
+				  ,FT_BYTES			,BASE_NONE		,NULL
+				  ,0				,NULL			,HFILL }},
+
+		{&hf_payload_l	,{"TDM payload length"		,"pwcesopsn.payload.len"
+				  ,FT_INT32			,BASE_DEC		,NULL
+				  ,0				,NULL			,HFILL }}
+	};
+
+	static gint *ett_array[] = {
+		&ett_pw_cesopsn
+	};
+	static ei_register_info ei[] = {
+		{ &ei_packet_size_too_small, { "pwcesopsn.packet_size_too_small", PI_MALFORMED, PI_ERROR, "PW packet size is too small to carry sensible information", EXPFILL }},
+		{ &ei_cw_bits03, { "pwcesopsn.cw.bits03.not_zero", PI_MALFORMED, PI_ERROR, "Bits 0..3 of Control Word must be 0", EXPFILL }},
+		{ &ei_cw_lm, { "pwcesopsn.cw.lm.reserved", PI_UNDECODED, PI_WARN, "Reserved combination of L and Modifier bits", EXPFILL }},
+		{ &ei_cw_frg, { "pwcesopsn.cw.frag.not_allowed", PI_MALFORMED, PI_ERROR, "Fragmentation of payload is not allowed for basic CESoPSN mode", EXPFILL }},
+		{ &ei_pref_cw_len, { "pwcesopsn.cw.length.invalid", PI_MALFORMED, PI_ERROR, "Bad Length: too small", EXPFILL }},
+		{ &ei_payload_size_invalid_error, { "pwcesopsn.payload.size_invalid", PI_MALFORMED, PI_ERROR, "CESoPSN payload size invalid", EXPFILL }},
+		{ &ei_payload_size_invalid_undecoded, { "pwcesopsn.payload.undecoded", PI_UNDECODED, PI_NOTE, "CESoPSN payload: omitted to conserve bandwidth", EXPFILL }},
+	};
+	expert_module_t* expert_pwcesopsn;
+
+	proto = proto_register_protocol(pwc_longname_pw_cesopsn, shortname, "pwcesopsn");
+	proto_register_field_array(proto, hf, array_length(hf));
+	proto_register_subtree_array(ett_array, array_length(ett_array));
+	expert_pwcesopsn = expert_register_protocol(proto);
+	expert_register_field_array(expert_pwcesopsn, ei, array_length(ei));
+	pw_cesopsn_mpls_handle = register_dissector("pw_cesopsn_mpls", dissect_pw_cesopsn_mpls, proto);
+	pw_cesopsn_udp_handle = register_dissector("pw_cesopsn_udp", dissect_pw_cesopsn_udp, proto);
+}
+
+
+void proto_reg_handoff_pw_cesopsn(void)
+{
+	pw_padding_handle = find_dissector_add_dependency("pw_padding", proto);
+
+	/* For Decode As */
+	dissector_add_for_decode_as("mpls.label", pw_cesopsn_mpls_handle);
+
+	dissector_add_for_decode_as_with_preference("udp.port", pw_cesopsn_udp_handle);
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 8
+ * tab-width: 8
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vi: set shiftwidth=8 tabstop=8 noexpandtab:
+ * :indentSize=8:tabSize=8:noTabs=false:
+ */