Add a dissector for the USB printer class.

Start dissecting the class-specific control messages.

Change-Id: I21e97777c9fc0396a8c0c575ba21909f58bbb577
Reviewed-on: https://code.wireshark.org/review/36539
Reviewed-by: Martin Kaiser <wireshark@kaiser.cx>
Petri-Dish: Martin Kaiser <wireshark@kaiser.cx>
Tested-by: Petri Dish Buildbot
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 190 insertions, 0 deletions

diff --git a/epan/dissectors/packet-usb-printer.c b/epan/dissectors/packet-usb-printer.c
new file mode 100644
index 0000000000..bf08ec45f0
--- /dev/null
+++ b/epan/dissectors/packet-usb-printer.c
@@ -0,0 +1,190 @@
+/* packet-usb-printer.c
+ *
+ * Copyright 2020, Martin Kaiser <martin@kaiser.cx>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+/*
+ * References:
+ *
+ * USB printer class specification
+ * https://www.usb.org/sites/default/files/usbprint11a021811.pdf
+ *
+ * IEEE 1284 (parallel peripheral interface for personal computers)
+ * http://kazus.ru/nuke/modules/Downloads/pub/148/0/IEEE%201284-2000.pdf
+ */
+
+#include "config.h"
+#include <epan/packet.h>
+#include <epan/proto.h>
+#include <epan/dissectors/packet-usb.h>
+#include <epan/value_string.h>
+
+static int proto_usb_printer = -1;
+
+static int hf_usb_printer_req = -1;
+static int hf_usb_printer_cfg_idx = -1;
+static int hf_usb_printer_intf = -1;
+static int hf_usb_printer_alt_set = -1;
+static int hf_usb_printer_max_len = -1;
+static int hf_usb_printer_dev_id_len = -1;
+static int hf_usb_printer_dev_id = -1;
+
+static gint ett_usb_printer   = -1;
+
+void proto_register_usb_printer(void);
+void proto_reg_handoff_usb_printer(void);
+
+#define REQ_GET_DEV_ID    0
+#define REQ_GET_PORT_STAT 1
+#define REQ_GET_SOFT_RST  2
+
+static const value_string usb_printer_req[] = {
+    { REQ_GET_DEV_ID,    "GET_DEVICE_ID" },
+    { REQ_GET_PORT_STAT, "GET_PORT_STATUS" },
+    { REQ_GET_SOFT_RST,  "SOFT_RESET" },
+    { 0, NULL }
+};
+
+static gint dissect_usb_printer_ctl(
+        tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
+{
+    gboolean is_request = (pinfo->srcport == NO_ENDPOINT);
+    usb_conv_info_t *usb_conv_info = (usb_conv_info_t *)data;
+    usb_trans_info_t *usb_trans_info;
+    gint offset = 0;
+    guint8 bReq;
+    guint32 dev_id_len;
+
+    if (!usb_conv_info)
+        return 0;
+
+    usb_trans_info = usb_conv_info->usb_trans_info;
+    if (!usb_trans_info)
+        return 0;
+
+    col_set_str(pinfo->cinfo, COL_PROTOCOL, "USBPRINTER");
+    col_set_str(pinfo->cinfo, COL_INFO,
+            val_to_str_const(usb_trans_info->setup.request,
+                usb_printer_req, "Invalid"));
+
+    if (is_request) {
+        col_append_fstr(pinfo->cinfo, COL_INFO, " request");
+
+        bReq = tvb_get_guint8(tvb, offset);
+        proto_tree_add_item(tree, hf_usb_printer_req,
+                tvb, offset, 1, ENC_LITTLE_ENDIAN);
+        offset++;
+
+        if (bReq == REQ_GET_DEV_ID) {
+            /* Generally, fields in USB messages are little endian. */
+            proto_tree_add_item(tree, hf_usb_printer_cfg_idx,
+                    tvb, offset, 2, ENC_LITTLE_ENDIAN);
+            offset += 2;
+            proto_tree_add_item(tree, hf_usb_printer_intf,
+                    tvb, offset, 2, ENC_LITTLE_ENDIAN);
+            proto_tree_add_item(tree, hf_usb_printer_alt_set,
+                    tvb, offset, 2, ENC_LITTLE_ENDIAN);
+            offset += 2;
+            proto_tree_add_item(tree, hf_usb_printer_max_len,
+                    tvb, offset, 2, ENC_LITTLE_ENDIAN);
+            offset += 2;
+        }
+    }
+    else {
+        col_append_fstr(pinfo->cinfo, COL_INFO, " response");
+
+        if (usb_trans_info->setup.request == REQ_GET_DEV_ID) {
+            /*
+             * A printer's Device ID is defined in IEEE 1284, section 7.6.
+             * It starts with a 16-bit length field in big endian encoding.
+             * The length field includes the two bytes for itself. Therefore,
+             * we can't use an FT_UINT_STRING for the entire Device ID.
+             * The actual Device ID string consists of ASCII characters.
+             */
+            proto_tree_add_item_ret_uint(tree, hf_usb_printer_dev_id_len,
+                    tvb, offset, 2, ENC_BIG_ENDIAN, &dev_id_len);
+            offset += 2;
+            if (dev_id_len > 2) {
+                proto_tree_add_item(tree, hf_usb_printer_dev_id,
+                        tvb, offset, dev_id_len-2, ENC_ASCII|ENC_NA);
+                offset += dev_id_len-2;
+            }
+            /* XXX - expert info for invalid dev_id_len */
+        }
+    }
+
+    return offset;
+}
+
+void proto_register_usb_printer(void)
+{
+    static hf_register_info hf[] = {
+        { &hf_usb_printer_req,
+            { "bRequest", "usbprinter.bRequest", FT_UINT8, BASE_HEX,
+                VALS(usb_printer_req), 0x0, NULL, HFILL }
+        },
+        { &hf_usb_printer_cfg_idx,
+            { "Config index", "usbprinter.config_index", FT_UINT16, BASE_HEX,
+                NULL, 0x0, NULL, HFILL }
+        },
+        { &hf_usb_printer_intf,
+            { "Interface", "usbprinter.interface", FT_UINT16, BASE_HEX,
+                NULL, 0xFF00, NULL, HFILL }
+        },
+        { &hf_usb_printer_alt_set,
+            { "Alternate setting", "usbprinter.alt_set", FT_UINT16, BASE_HEX,
+                NULL, 0x00FF, NULL, HFILL }
+        },
+        { &hf_usb_printer_max_len,
+            { "Maximum length", "usbprinter.max_len", FT_UINT16, BASE_HEX,
+                NULL, 0, NULL, HFILL }
+        },
+        { &hf_usb_printer_dev_id_len,
+            { "Device ID length", "usbprinter.device_id_len", FT_UINT16,
+                BASE_HEX, NULL, 0, NULL, HFILL }
+        },
+        { &hf_usb_printer_dev_id,
+            { "Device ID", "usbprinter.device_id", FT_STRING, BASE_NONE,
+                NULL, 0, NULL, HFILL }
+        }
+    };
+
+    static gint *ett[] = {
+        &ett_usb_printer
+    };
+
+    proto_usb_printer = proto_register_protocol(
+            "USB Printer", "USBPRINTER", "usbprinter");
+    proto_register_field_array(proto_usb_printer, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_usb_printer(void)
+{
+    dissector_handle_t usb_printer_ctl_handle;
+
+    usb_printer_ctl_handle = create_dissector_handle(
+            dissect_usb_printer_ctl, proto_usb_printer);
+
+    dissector_add_uint("usb.control", IF_CLASS_PRINTER, usb_printer_ctl_handle);
+}
+
+/*
+* Editor modelines - https://www.wireshark.org/tools/modelines.html
+*
+* Local variables:
+* c-basic-offset: 4
+* tab-width: 8
+* indent-tabs-mode: nil
+* End:
+*
+* ex: set shiftwidth=4 tabstop=8 expandtab:
+* :indentSize=4:tabSize=8:noTabs=true:
+*/