From Ishraq Ibne Ashraf: Tinkerforge protocol dissector

See: https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=9324

From me:

1. Move certain global vars to local storage in dissect_tfp_common()

2. Declare all remaining global vars as static;

3. Fix some bugs:
    - base58_encode() needed to be called before call to col_add_fstr()
    - display of UID string in tree was being truncated to 4 characters

4. Cleanup whitespace: use consistent indentation (tabs); remove trailing whitespace;

5. Add editor modelines




svn path=/trunk/; revision=52931

3 files changed, 445 insertions, 0 deletions

diff --git a/epan/CMakeLists.txt b/epan/CMakeLists.txt
index cf589c6bbd..697666ff1e 100644
--- a/epan/CMakeLists.txt
+++ b/epan/CMakeLists.txt
@@ -1200,6 +1200,7 @@ set(DISSECTOR_SRC
 	dissectors/packet-telnet.c
 	dissectors/packet-teredo.c
 	dissectors/packet-text-media.c
+	dissectors/packet-tfp.c
 	dissectors/packet-tftp.c
 	dissectors/packet-time.c
 	dissectors/packet-tipc.c
diff --git a/epan/dissectors/Makefile.common b/epan/dissectors/Makefile.common
index 3cfa89feb2..c8c6ba5cb4 100644
--- a/epan/dissectors/Makefile.common
+++ b/epan/dissectors/Makefile.common
@@ -1127,6 +1127,7 @@ DISSECTOR_SRC = \
 	packet-telnet.c		\
 	packet-teredo.c		\
 	packet-text-media.c	\
+	packet-tfp.c		\
 	packet-tftp.c		\
 	packet-time.c		\
 	packet-tipc.c		\
diff --git a/epan/dissectors/packet-tfp.c b/epan/dissectors/packet-tfp.c
new file mode 100644
index 0000000000..fa8c00a3e8
--- /dev/null
+++ b/epan/dissectors/packet-tfp.c
@@ -0,0 +1,443 @@
+/* packet-tfp.c
+ * Routines for Tinkerforge protocol packet disassembly
+ * By Ishraq Ibne Ashraf <ishraq@tinkerforge.com>
+ * Copyright 2013 Ishraq Ibne Ashraf
+ *
+ * $Id$
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <epan/packet.h>
+#include <epan/dissectors/packet-usb.h>
+
+/* defines */
+#define tfp_PORT 4223
+
+#define tfp_USB_VENDOR_ID  0x16D0
+#define tfp_USB_PRODUCT_ID 0x063D
+
+#define BASE58_MAX_STR_SIZE 13
+
+/* variables for creating the tree */
+static gint proto_tfp = -1;
+static gint ett_tfp = -1;
+
+/* header field variables */
+static gint hf_tfp_uid = -1;
+static gint hf_tfp_uid_numeric = -1;
+static gint hf_tfp_len = -1;
+static gint hf_tfp_fid = -1;
+static gint hf_tfp_seq = -1;
+static gint hf_tfp_r = -1;
+static gint hf_tfp_a = -1;
+static gint hf_tfp_oo = -1;
+static gint hf_tfp_e = -1;
+static gint hf_tfp_future_use = -1;
+static gint hf_tfp_payload = -1;
+
+/* bit and byte offsets for dissection */
+static const gint byte_offset_len	   = 4;
+static const gint byte_offset_fid	   = 5;
+static const gint byte_count_tfp_uid	   = 4;
+static const gint byte_count_tfp_len	   = 1;
+static const gint byte_count_tfp_fid	   = 1;
+static const gint byte_count_tfp_flags	   = 2;
+static const gint bit_count_tfp_seq	   = 4;
+static const gint bit_count_tfp_r	   = 1;
+static const gint bit_count_tfp_a	   = 1;
+static const gint bit_count_tfp_oo	   = 2;
+static const gint bit_count_tfp_e	   = 2;
+static const gint bit_count_tfp_future_use = 6;
+
+/* base58 encoding variable */
+static const char BASE58_ALPHABET[] =
+	"123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ";
+
+/* function for encoding a number to base58 string */
+static void
+base58_encode(guint32 value, char *str) {
+
+	guint32 mod;
+	gint    i = 0;
+	gint    k;
+	gchar	reverse_str[BASE58_MAX_STR_SIZE] = {'\0'};
+
+	while (value >= 58) {
+		mod = value % 58;
+		reverse_str[i] = BASE58_ALPHABET[mod];
+		value = value / 58;
+		++i;
+	}
+
+	reverse_str[i] = BASE58_ALPHABET[value];
+
+	for (k = 0; k <= i; k++) {
+		str[k] = reverse_str[i - k];
+	}
+
+	for (; k < BASE58_MAX_STR_SIZE; k++) {
+		str[k] = '\0';
+	}
+}
+
+/* common dissector function for dissecting TFP payloads */
+static void
+dissect_tfp_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
+
+	gint   byte_offset = 0;
+	gint   bit_offset  = 48;
+
+	guint8 hv_tfp_len;
+	guint8 hv_tfp_fid;
+	guint8 hv_tfp_seq;
+
+	gchar  tfp_uid_string[BASE58_MAX_STR_SIZE];
+
+	base58_encode(tvb_get_letohl(tvb, 0), &tfp_uid_string[0]);
+
+	hv_tfp_len = tvb_get_guint8(tvb, byte_offset_len);
+	hv_tfp_fid = tvb_get_guint8(tvb, byte_offset_fid);
+	hv_tfp_seq = tvb_get_bits8(tvb, bit_offset, bit_count_tfp_seq);
+
+	col_add_fstr(pinfo->cinfo, COL_INFO,
+			"UID: %s, Len: %d, FID: %d, Seq: %d",
+			&tfp_uid_string[0], hv_tfp_len, hv_tfp_fid, hv_tfp_seq);
+
+	/* call for details */
+	if (tree) {
+		proto_tree *tfp_tree;
+		proto_item *ti;
+
+		ti = proto_tree_add_protocol_format(tree, proto_tfp, tvb, 0, -1,
+						    "Tinkerforge Protocol, UID: %s, Len: %d, FID: %d, Seq: %d",
+						    &tfp_uid_string[0], hv_tfp_len, hv_tfp_fid, hv_tfp_seq);
+		tfp_tree = proto_item_add_subtree(ti, ett_tfp);
+
+		/* Use ...string_format_value() so we can show the complete generated string but specify */
+		/*  the field length as being just the 4 bytes from which the string is generated.	 */
+		ti = proto_tree_add_string_format_value(tfp_tree,
+							hf_tfp_uid,
+							tvb, byte_offset, byte_count_tfp_uid,
+							&tfp_uid_string[0], "%s", &tfp_uid_string[0]);
+		PROTO_ITEM_SET_GENERATED(ti);
+
+		proto_tree_add_item(tfp_tree,
+				    hf_tfp_uid_numeric,
+				    tvb,
+				    byte_offset,
+				    byte_count_tfp_uid,
+				    ENC_LITTLE_ENDIAN);
+
+		byte_offset += byte_count_tfp_uid;
+
+		proto_tree_add_item(tfp_tree,
+				    hf_tfp_len,
+				    tvb,
+				    byte_offset,
+				    byte_count_tfp_len,
+				    ENC_LITTLE_ENDIAN);
+
+		byte_offset += byte_count_tfp_len;
+
+		proto_tree_add_item(tfp_tree,
+				    hf_tfp_fid,
+				    tvb,
+				    byte_offset,
+				    byte_count_tfp_fid,
+				    ENC_LITTLE_ENDIAN);
+
+		byte_offset += byte_count_tfp_fid;
+
+		proto_tree_add_bits_item(tfp_tree,
+					 hf_tfp_seq,
+					 tvb,
+					 bit_offset,
+					 bit_count_tfp_seq,
+					 ENC_LITTLE_ENDIAN);
+
+		bit_offset += bit_count_tfp_seq;
+
+		proto_tree_add_bits_item(tfp_tree,
+					 hf_tfp_r,
+					 tvb,
+					 bit_offset,
+					 bit_count_tfp_r,
+					 ENC_LITTLE_ENDIAN);
+
+		bit_offset += bit_count_tfp_r;
+
+		proto_tree_add_bits_item(tfp_tree,
+					 hf_tfp_a,
+					 tvb,
+					 bit_offset,
+					 bit_count_tfp_a,
+					 ENC_LITTLE_ENDIAN);
+
+		bit_offset += bit_count_tfp_a;
+
+		proto_tree_add_bits_item(tfp_tree,
+					 hf_tfp_oo,
+					 tvb,
+					 bit_offset,
+					 bit_count_tfp_oo,
+					 ENC_LITTLE_ENDIAN);
+
+		bit_offset += bit_count_tfp_oo;
+
+		proto_tree_add_bits_item(tfp_tree,
+					 hf_tfp_e,
+					 tvb,
+					 bit_offset,
+					 bit_count_tfp_e,
+					 ENC_LITTLE_ENDIAN);
+
+		bit_offset += bit_count_tfp_e;
+
+		proto_tree_add_bits_item(tfp_tree,
+					 hf_tfp_future_use,
+					 tvb,
+					 bit_offset,
+					 bit_count_tfp_future_use,
+					 ENC_LITTLE_ENDIAN);
+
+		bit_offset += bit_count_tfp_future_use;
+
+		if ((tvb_reported_length(tvb)) > 8) {
+
+			byte_offset += byte_count_tfp_flags;
+
+			proto_tree_add_item(tfp_tree,
+				    	    hf_tfp_payload,
+				    	    tvb,
+				    	    byte_offset,
+				    	    -1,
+				    	    ENC_NA);
+		}
+  	}
+}
+
+/* dissector function for dissecting TCP payloads */
+static void
+dissect_tfp_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	col_set_str(pinfo->cinfo, COL_PROTOCOL, "TFP over TCP");
+  	col_clear(pinfo->cinfo, COL_INFO);
+
+	dissect_tfp_common(tvb, pinfo, tree);
+}
+
+/* dissector function for dissecting USB payloads */
+static void
+dissect_tfp_usb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+	usb_conv_info_t *usb_conv_info;
+	usb_conv_info = (usb_conv_info_t *)pinfo->usb_conv_info;
+
+	if (usb_conv_info->deviceVendor == tfp_USB_VENDOR_ID) {
+		col_set_str(pinfo->cinfo, COL_PROTOCOL, "TFP over USB");
+		if (usb_conv_info->deviceProduct == tfp_USB_PRODUCT_ID) {
+			col_clear(pinfo->cinfo, COL_INFO);
+			dissect_tfp_common(tvb, pinfo, tree);
+		}
+		else {
+			/* ToDo? Display "Unknown Product" ?? */
+		}
+		return;
+	}
+	else {
+		return; /* Not tfp_USB_VENDOR_ID */
+	}
+}
+
+/* protocol register function */
+void
+proto_register_tfp(void)
+{
+	/* defining header formats */
+	static hf_register_info hf_tfp[] = {
+		{ &hf_tfp_uid,
+			{ "UID (String)",
+			  "tfp.uid",
+			  FT_STRINGZ,
+			  BASE_NONE,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_uid_numeric,
+			{ "UID (Numeric)",
+			  "tfp.uid_numeric",
+			  FT_UINT32,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_len,
+			{ "Length",
+			  "tfp.len",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_fid,
+			{ "Function ID",
+			  "tfp.fid",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_seq,
+			{ "Sequence Number",
+			  "tfp.seq",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_r,
+			{ "Response Expected",
+			  "tfp.r",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_a,
+			{ "Authentication",
+			  "tfp.a",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_oo,
+			{ "Other Options",
+			  "tfp.oo",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_e,
+			{ "Error Code",
+			  "tfp.e",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_future_use,
+			{ "Future Use",
+			  "tfp.future_use",
+			  FT_UINT8,
+			  BASE_DEC,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		},
+		{ &hf_tfp_payload,
+			{ "Payload",
+			  "tfp.payload",
+			  FT_BYTES,
+			  BASE_NONE,
+			  NULL,
+			  0x0,
+			  NULL,
+			  HFILL
+			}
+		}
+	};
+
+	/* setup protocol subtree array */
+	static gint *ett[] = {
+		&ett_tfp
+	};
+
+	/* defining the protocol and its names */
+	proto_tfp = proto_register_protocol (
+		"Tinkerforge Protocol",
+		"TFP",
+		"tfp"
+	);
+
+	proto_register_field_array(proto_tfp, hf_tfp, array_length(hf_tfp));
+	proto_register_subtree_array(ett, array_length(ett));
+}
+
+/* handoff function */
+void
+proto_reg_handoff_tfp(void) {
+
+	static dissector_handle_t
+		tfp_handle_tcp,
+		tfp_handle_usb;
+
+	tfp_handle_tcp = create_dissector_handle(dissect_tfp_tcp, proto_tfp);
+	tfp_handle_usb = create_dissector_handle(dissect_tfp_usb, proto_tfp);
+
+	dissector_add_uint("tcp.port", tfp_PORT, tfp_handle_tcp);
+	dissector_add_uint("usb.bulk", IF_CLASS_VENDOR_SPECIFIC, tfp_handle_usb);
+}
+
+/*
+ * Editor modelines  -  http://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:
+ */