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-rw-r--r--epan/dissectors/packet-ippusb.c552
1 files changed, 552 insertions, 0 deletions
diff --git a/epan/dissectors/packet-ippusb.c b/epan/dissectors/packet-ippusb.c
new file mode 100644
index 00000000..e2f9e963
--- /dev/null
+++ b/epan/dissectors/packet-ippusb.c
@@ -0,0 +1,552 @@
+/* packet-ippusb.c
+ * Routines for IPPUSB packet disassembly
+ * https://robots.org.uk/IPPOverUSB
+ *
+ * Jamie Hare <jamienh@umich.edu>
+ *
+ * PROTONAME: Internet Printing Protocol Over USB
+ * PROTOSHORTNAME: IPPUSB
+ * PROTOABBREV: ippusb
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/strutil.h>
+#include <epan/to_str.h>
+#include <epan/conversation.h>
+#include <epan/wmem_scopes.h>
+#include <reassemble.h>
+#include "packet-usb.h"
+
+/*
+ * IPPUSB transfer_type values
+ */
+#define HTTP 0
+
+/* As also defined in IPP dissector */
+#define PRINT_JOB 0x0002
+#define SEND_DOCUMENT 0x0006
+
+#define TAG_END_OF_ATTRIBUTES 0x03
+#define NEWLINE 0x0a
+
+#define CHUNK_LENGTH_MIN 5
+
+#define BITS_PER_BYTE 8
+
+static const guint8 CHUNKED_END[] = { 0x30, 0x0d, 0x0a, 0x0d, 0x0a };
+static const guint8 RETURN_NEWLINE[] = { 0x0d, 0x0a };
+static tvbuff_t *return_newline_tvb = NULL;
+
+void proto_register_ippusb(void);
+void proto_reg_handoff_ippusb(void);
+static gint is_http_header(guint first_linelen, const guchar *first_line);
+
+static dissector_handle_t ippusb_handle;
+
+static gint proto_ippusb = -1;
+static gint ett_ippusb = -1;
+static gint ett_ippusb_as = -1;
+static gint ett_ippusb_attr = -1;
+static gint ett_ippusb_member = -1;
+static gint ett_ippusb_fragment= -1;
+static gint ett_ippusb_fragments = -1;
+
+/* For reassembly */
+static gint32 ippusb_last_pdu = -1;
+
+static gint hf_ippusb_fragments = -1;
+static gint hf_ippusb_fragment = -1;
+static gint hf_ippusb_fragment_overlap = -1;
+static gint hf_ippusb_fragment_overlap_conflict = -1;
+static gint hf_ippusb_fragment_multiple_tails = -1;
+static gint hf_ippusb_fragment_too_long_fragment = -1;
+static gint hf_ippusb_fragment_error = -1;
+static gint hf_ippusb_fragment_count = -1;
+static gint hf_ippusb_reassembled_in = -1;
+static gint hf_ippusb_reassembled_length = -1;
+static gint hf_ippusb_reassembled_data = -1;
+
+/* Reassemble by default */
+static gboolean global_ippusb_reassemble = TRUE;
+
+static const fragment_items ippusb_frag_items = {
+ &ett_ippusb_fragment,
+ &ett_ippusb_fragments,
+ &hf_ippusb_fragments,
+ &hf_ippusb_fragment,
+ &hf_ippusb_fragment_overlap,
+ &hf_ippusb_fragment_overlap_conflict,
+ &hf_ippusb_fragment_multiple_tails,
+ &hf_ippusb_fragment_too_long_fragment,
+ &hf_ippusb_fragment_error,
+ &hf_ippusb_fragment_count,
+ &hf_ippusb_reassembled_in,
+ &hf_ippusb_reassembled_length,
+ &hf_ippusb_reassembled_data,
+ "IPPUSB fragments"
+};
+
+struct ippusb_multisegment_pdu {
+ guint nxtpdu;
+ guint32 first_frame;
+ guint32 running_size;
+ gboolean finished;
+ gboolean reassembled;
+ gboolean is_ipp;
+
+ guint32 document;
+ #define MSP_HAS_DOCUMENT 0x00000001
+ #define MSP_DOCUMENT_TRUNCATED 0x00000002
+
+ guint32 flags;
+ #define MSP_FLAGS_REASSEMBLE_ENTIRE_SEGMENT 0x00000001
+ #define MSP_FLAGS_GOT_ALL_SEGMENTS 0x00000002
+ #define MSP_FLAGS_MISSING_FIRST_SEGMENT 0x00000004
+};
+
+static struct ippusb_multisegment_pdu *
+pdu_store(packet_info *pinfo, wmem_tree_t *multisegment_pdus, guint32 first_frame, gboolean is_ipp, guint document)
+{
+ struct ippusb_multisegment_pdu *msp;
+
+ msp = wmem_new(wmem_file_scope(), struct ippusb_multisegment_pdu);
+ msp->first_frame = first_frame;
+ msp->finished = FALSE;
+ msp->reassembled = FALSE;
+ msp->is_ipp = is_ipp;
+ msp->document = document;
+ msp->flags = 0;
+ wmem_tree_insert32(multisegment_pdus, pinfo->num, (void *)msp);
+
+ return msp;
+}
+
+struct ippusb_analysis {
+ wmem_tree_t *multisegment_pdus;
+};
+
+static struct ippusb_analysis *
+init_ippusb_conversation_data(void)
+{
+ struct ippusb_analysis *ippusbd;
+
+ ippusbd = wmem_new0(wmem_file_scope(), struct ippusb_analysis);
+
+ ippusbd->multisegment_pdus = wmem_tree_new(wmem_file_scope());
+
+ return ippusbd;
+}
+
+static struct ippusb_analysis *
+get_ippusb_conversation_data(conversation_t *conv, packet_info *pinfo)
+{
+ struct ippusb_analysis *ippusbd;
+
+ if(conv == NULL ) {
+ conv = find_or_create_conversation(pinfo);
+ }
+
+ ippusbd = (struct ippusb_analysis *)conversation_get_proto_data(conv, proto_ippusb);
+
+ if (!ippusbd) {
+ ippusbd = init_ippusb_conversation_data();
+ conversation_add_proto_data(conv, proto_ippusb, ippusbd);
+ }
+
+ return ippusbd;
+}
+
+
+static gpointer ippusb_temporary_key(const packet_info *pinfo _U_, const guint32 id _U_, const void *data)
+{
+ return (gpointer)data;
+}
+
+static gpointer ippusb_persistent_key(const packet_info *pinfo _U_, const guint32 id _U_, const void *data)
+{
+ return (gpointer)data;
+}
+
+static void ippusb_free_temporary_key(gpointer ptr _U_) { }
+
+static void ippusb_free_persistent_key(gpointer ptr _U_) { }
+
+static reassembly_table_functions ippusb_reassembly_table_functions =
+{
+ g_direct_hash,
+ g_direct_equal,
+ ippusb_temporary_key,
+ ippusb_persistent_key,
+ ippusb_free_temporary_key,
+ ippusb_free_persistent_key
+};
+
+static dissector_table_t ippusb_dissector_table;
+static reassembly_table ippusb_reassembly_table;
+
+/* Main dissector function */
+static int
+dissect_ippusb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
+{
+ gint offset = 0;
+ gint ret = 0;
+ guint first_linelen;
+ const guchar *first_line;
+ gint next_offset;
+ guint8 last;
+ guint8 status_code;
+ const guchar *last_chunk = NULL;
+ struct ippusb_analysis *ippusbd = NULL;
+ conversation_t *conv = NULL;
+
+ struct ippusb_multisegment_pdu *new_msp = NULL;
+ struct ippusb_multisegment_pdu *current_msp = NULL;
+ struct ippusb_multisegment_pdu *previous_msp = NULL;
+
+ gint reported_length = tvb_reported_length(tvb);
+ gint captured_length = tvb_captured_length(tvb);
+
+ if((conv = find_conversation_pinfo(pinfo, 0)) != NULL) {
+ /* Update how far the conversation reaches */
+ if (pinfo->num > conv->last_frame) {
+ conv->last_frame = pinfo->num;
+ }
+ }
+ else {
+ conv = conversation_new(pinfo->num, &pinfo->src, &pinfo->dst, CONVERSATION_TCP,
+ pinfo->srcport, pinfo->destport, 0);
+ }
+
+ ippusbd = get_ippusb_conversation_data(conv, pinfo);
+
+ first_linelen = tvb_find_line_end(tvb, offset, tvb_ensure_captured_length_remaining(tvb, offset), &next_offset, TRUE);
+ first_line = tvb_get_ptr(tvb, offset, first_linelen);
+
+ /* Get last byte of segment */
+ last = tvb_get_guint8(tvb, captured_length - 1);
+ status_code = tvb_get_bits8(tvb, 3 * BITS_PER_BYTE, BITS_PER_BYTE);
+
+ /* If segment has length of last chunk from chunk transfer */
+ if(captured_length == CHUNK_LENGTH_MIN){
+ last_chunk = tvb_get_ptr(tvb, offset, captured_length);
+ }
+
+ if (is_http_header(first_linelen, first_line) && last == TAG_END_OF_ATTRIBUTES && status_code != PRINT_JOB && status_code != SEND_DOCUMENT) {
+ /* An indiviual ippusb packet with http header */
+
+ proto_tree_add_item(tree, proto_ippusb, tvb, offset, -1, ENC_NA);
+
+ if (ippusb_last_pdu >= 0 && !pinfo->fd->visited) {
+ ippusb_last_pdu = -1;
+ }
+
+ ret = dissector_try_uint_new(ippusb_dissector_table, HTTP, tvb, pinfo, tree, TRUE, data);
+ }
+ else if (global_ippusb_reassemble) {
+ /* If reassembly is wanted */
+
+ if (!pinfo->fd->visited) {
+ /* First time this segment is ever seen */
+
+ gboolean save_fragmented = pinfo->fragmented;
+ pinfo->fragmented = TRUE;
+
+ proto_tree_add_item(tree, proto_ippusb, tvb, offset, -1, ENC_NA);
+
+ if (is_http_header(first_linelen, first_line)) {
+ /* The start of a new packet that will need to be reassembled */
+
+ new_msp = pdu_store(pinfo, ippusbd->multisegment_pdus, pinfo->num, TRUE, 0);
+ new_msp->running_size = captured_length;
+
+ fragment_add_check(&ippusb_reassembly_table, tvb, offset, pinfo, new_msp->first_frame,
+ GUINT_TO_POINTER(new_msp->first_frame), 0, captured_length, TRUE);
+
+ ippusb_last_pdu = pinfo->num;
+ }
+ else {
+
+ previous_msp = (struct ippusb_multisegment_pdu *)wmem_tree_lookup32_le(ippusbd->multisegment_pdus, ippusb_last_pdu);
+
+ if (previous_msp) {
+ previous_msp->nxtpdu = pinfo->num;
+ new_msp = pdu_store(pinfo, ippusbd->multisegment_pdus, previous_msp->first_frame, previous_msp->is_ipp, previous_msp->document);
+ new_msp->running_size = previous_msp->running_size + captured_length;
+
+ /* This packet has an HTTP header but is not an ipp packet */
+ if ((first_linelen >= strlen("Content-Type: ") && strncmp(first_line, "Content-Type: ", strlen("Content-Type: ")) == 0) &&
+ (first_linelen < strlen("Content-Type: application/ipp") || strncmp(first_line, "Content-Type: application/ipp", strlen("Content-Type: application/ipp")) != 0)) {
+ new_msp->is_ipp = FALSE;
+ }
+
+ /* This packet will have an attached document */
+ if (status_code == PRINT_JOB || status_code == SEND_DOCUMENT) {
+ new_msp->document |= MSP_HAS_DOCUMENT;
+ }
+
+ if(!(last_chunk && strncmp(last_chunk, CHUNKED_END, CHUNK_LENGTH_MIN) == 0)){
+ /* If this segment is not the last chunk in a chunked transfer */
+
+ if (captured_length < reported_length && (new_msp->document & MSP_HAS_DOCUMENT)) {
+ /* The attached document segment is smaller than it says it should be and cannot be reaseembled properly */
+
+ tvbuff_t *new_tvb = tvb_new_subset_length(tvb, 0, captured_length);
+
+ fragment_add_check(&ippusb_reassembly_table, new_tvb, offset, pinfo, new_msp->first_frame,
+ GUINT_TO_POINTER(new_msp->first_frame), previous_msp->running_size, captured_length, TRUE);
+
+ new_msp->document |= MSP_DOCUMENT_TRUNCATED;
+ }
+ else {
+ fragment_add_check(&ippusb_reassembly_table, tvb, offset, pinfo, new_msp->first_frame,
+ GUINT_TO_POINTER(new_msp->first_frame), previous_msp->running_size, captured_length, TRUE);
+ }
+
+ if (last != NEWLINE) {
+ fragment_add_check(&ippusb_reassembly_table, return_newline_tvb, offset, pinfo, new_msp->first_frame,
+ GUINT_TO_POINTER(new_msp->first_frame), new_msp->running_size, sizeof(RETURN_NEWLINE), TRUE);
+
+ new_msp->running_size += sizeof(RETURN_NEWLINE);
+ }
+
+ ippusb_last_pdu = pinfo->num;
+ }
+ else {
+ /* This segment contains the end of ipp chunked transfer information */
+
+ new_msp->finished = TRUE;
+ ippusb_last_pdu = -1;
+
+ fragment_head *head = fragment_add_check(&ippusb_reassembly_table, tvb, offset, pinfo, new_msp->first_frame,
+ GUINT_TO_POINTER(new_msp->first_frame), previous_msp->running_size, captured_length, FALSE);
+ tvbuff_t *processed_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled IPPUSB", head, &ippusb_frag_items, NULL, tree);
+
+ new_msp->reassembled = TRUE;
+ pinfo->can_desegment = 0;
+
+ if(processed_tvb){
+ ret = dissector_try_uint_new(ippusb_dissector_table, HTTP, processed_tvb, pinfo, tree, TRUE, data);
+ col_append_fstr(pinfo->cinfo, COL_INFO, " Reassembled Data");
+ }
+ }
+ }
+
+ pinfo->fragmented = save_fragmented;
+ }
+ }
+ else {
+ /* Not the first time this segment is seen */
+
+ gboolean save_fragmented = pinfo->fragmented;
+ pinfo->fragmented = TRUE;
+ current_msp = (struct ippusb_multisegment_pdu *)wmem_tree_lookup32_le(ippusbd->multisegment_pdus, pinfo->num);
+
+ /* This is not an ipp packet */
+ if(current_msp && !(current_msp->is_ipp)){
+ return captured_length;
+ }
+
+ if (current_msp && !current_msp->finished && current_msp->nxtpdu == 0) {
+ /* This is a packet that was not completed and assembly will be attempted */
+
+ proto_tree_add_item(tree, proto_ippusb, tvb, offset, -1, ENC_NA);
+ fragment_head *head;
+
+ if (!current_msp->reassembled) {
+ /* The first time this segment is passed over after the initial round
+ * it will be added to the pdu and reassembled */
+
+ pinfo->fd->visited = FALSE;
+
+ if (captured_length < reported_length && (current_msp->document & MSP_HAS_DOCUMENT)) {
+ /* The attached document segment is smaller than it says it should be and cannot be reaseembled properly */
+
+ tvbuff_t *new_tvb = tvb_new_subset_length(tvb, 0, captured_length);
+
+ head = fragment_add_check(&ippusb_reassembly_table, new_tvb, offset, pinfo, current_msp->first_frame,
+ GUINT_TO_POINTER(current_msp->first_frame), current_msp->running_size - captured_length, captured_length, FALSE);
+
+ current_msp->document |= MSP_DOCUMENT_TRUNCATED;
+ }
+ else {
+ head = fragment_add_check(&ippusb_reassembly_table, tvb, 0, pinfo, current_msp->first_frame,
+ GUINT_TO_POINTER(current_msp->first_frame), current_msp->running_size - captured_length, captured_length, FALSE);
+ }
+
+ pinfo->fd->visited = TRUE;
+
+ current_msp->reassembled = TRUE;
+ }
+ else {
+ /* Packet has already been reassembled */
+
+ head = fragment_get_reassembled_id(&ippusb_reassembly_table, pinfo, current_msp->first_frame);
+ }
+
+ tvbuff_t *processed_tvb = process_reassembled_data(tvb, offset, pinfo, " Reassembled IPPUSB", head, &ippusb_frag_items, NULL, tree);
+
+ if (processed_tvb) {
+ pinfo->can_desegment = 0;
+
+ ret = dissector_try_uint_new(ippusb_dissector_table, HTTP, processed_tvb, pinfo, tree, TRUE, data);
+
+ if (current_msp->document & MSP_DOCUMENT_TRUNCATED) {
+ col_append_fstr(pinfo->cinfo, COL_INFO, " Document Truncated");
+ }
+ }
+ }
+ else if (current_msp &&last_chunk && strncmp(last_chunk, CHUNKED_END, CHUNK_LENGTH_MIN) == 0) {
+ /* This is the last segment of the chunked transfer and reassembled packet */
+
+ proto_tree_add_item(tree, proto_ippusb, tvb, offset, -1, ENC_NA);
+
+ fragment_head *head = fragment_get_reassembled_id(&ippusb_reassembly_table, pinfo, current_msp->first_frame);
+
+ tvbuff_t *processed_tvb = process_reassembled_data(tvb, offset, pinfo, " Reassembled IPPUSB", head, &ippusb_frag_items, NULL, tree);
+
+ if (processed_tvb) {
+ pinfo->can_desegment = 0;
+
+ ret = dissector_try_uint_new(ippusb_dissector_table, HTTP, processed_tvb, pinfo, tree, TRUE, data);
+
+ col_append_fstr(pinfo->cinfo, COL_INFO, " Reassembled Data");
+
+ /* If the document was truncated mark it as such in the UX */
+ if (current_msp->document & MSP_DOCUMENT_TRUNCATED) {
+ col_append_fstr(pinfo->cinfo, COL_INFO, " Document Truncated");
+ }
+ }
+ }
+
+ pinfo->fragmented = save_fragmented;
+ }
+ }
+
+ if (ret) {
+ return tvb_captured_length(tvb);
+ }
+ else {
+ return 0;
+ }
+}
+
+static gint
+is_http_header(guint first_linelen, const guchar *first_line) {
+ if ((first_linelen >= strlen("HTTP/") && strncmp(first_line, "HTTP/", strlen("HTTP/")) == 0) ||
+ (first_linelen >= strlen("POST /ipp") && strncmp(first_line, "POST /ipp", strlen("POST /ipp")) == 0) ||
+ (first_linelen >= strlen("POST / HTTP") && strncmp(first_line, "POST / HTTP", strlen("POST / HTTP")) == 0)) {
+
+ return TRUE;
+ }
+ else {
+ return FALSE;
+ }
+}
+
+static void
+ippusb_shutdown(void) {
+ tvb_free(return_newline_tvb);
+}
+
+void
+proto_register_ippusb(void)
+{
+ static hf_register_info hf[] = {
+
+ /* Reassembly */
+ { &hf_ippusb_fragment,
+ { "Fragment", "ippusb.fragment", FT_FRAMENUM, BASE_NONE,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_ippusb_fragments,
+ { "Fragments", "ippusb.fragments", FT_BYTES, BASE_NONE,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_ippusb_fragment_overlap,
+ { "Fragment overlap", "ippusb.fragment.overlap", FT_BOOLEAN, BASE_NONE,
+ NULL, 0x0, "Fragment overlaps with other fragments", HFILL }},
+ { &hf_ippusb_fragment_overlap_conflict,
+ { "Conflicting data in fragment overlap", "ippusb.fragment.overlap.conflict",
+ FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Overlapping fragments contained conflicting data", HFILL }},
+ { &hf_ippusb_fragment_multiple_tails,
+ { "Multiple tail fragments found", "ippusb.fragment.multipletails",
+ FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Several tails were found when defragmenting the packet", HFILL }},
+ { &hf_ippusb_fragment_too_long_fragment,
+ { "Fragment too long", "ippusb.fragment.toolongfragment",
+ FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Fragment contained data past end of packet", HFILL }},
+ { &hf_ippusb_fragment_error,
+ { "Defragmentation error", "ippusb.fragment.error", FT_FRAMENUM, BASE_NONE,
+ NULL, 0x0, "Defragmentation error due to illegal fragments", HFILL }},
+ { &hf_ippusb_fragment_count,
+ { "Fragment count", "ippusb.fragment.count", FT_UINT32, BASE_DEC,
+ NULL, 0x0, NULL, HFILL }},
+ { &hf_ippusb_reassembled_in,
+ { "Reassembled payload in frame", "ippusb.reassembled_in", FT_FRAMENUM, BASE_NONE,
+ NULL, 0x0, "This payload packet is reassembled in this frame", HFILL }},
+ { &hf_ippusb_reassembled_length,
+ { "Reassembled payload length", "ippusb.reassembled.length", FT_UINT32, BASE_DEC,
+ NULL, 0x0, "The total length of the reassembled payload", HFILL }},
+ { &hf_ippusb_reassembled_data,
+ { "Reassembled data", "ippusb.reassembled.data", FT_BYTES, BASE_NONE,
+ NULL, 0x0, "The reassembled payload", HFILL }},
+ };
+
+ static gint *ett[] = {
+ &ett_ippusb,
+ &ett_ippusb_as,
+ &ett_ippusb_attr,
+ &ett_ippusb_member,
+ &ett_ippusb_fragments,
+ &ett_ippusb_fragment
+ };
+
+ proto_ippusb = proto_register_protocol("Internet Printing Protocol Over USB", "IPPUSB", "ippusb");
+
+ ippusb_dissector_table = register_dissector_table("ippusb", "IPP Over USB", proto_ippusb, FT_UINT8, BASE_DEC);
+
+ proto_register_field_array(proto_ippusb, hf, array_length(hf));
+ proto_register_subtree_array(ett, array_length(ett));
+
+ /* Register reassembly table. */
+ reassembly_table_register(&ippusb_reassembly_table, &ippusb_reassembly_table_functions);
+
+ /* Preferences */
+ module_t *ippusb_module = prefs_register_protocol(proto_ippusb, NULL);
+
+ /* Reassembly, made an option due to memory costs */
+ prefs_register_bool_preference(ippusb_module, "attempt_reassembly", "Reassemble payload", "", &global_ippusb_reassemble);
+
+ return_newline_tvb = tvb_new_real_data(RETURN_NEWLINE, sizeof(RETURN_NEWLINE), sizeof(RETURN_NEWLINE));
+
+ register_shutdown_routine(ippusb_shutdown);
+
+ ippusb_handle = register_dissector("ippusb", dissect_ippusb, proto_ippusb);
+}
+
+void
+proto_reg_handoff_ippusb(void)
+{
+ dissector_add_uint("usb.bulk", IF_CLASS_PRINTER, ippusb_handle);
+}
+
+/*
+ * Editor modelines - https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */
generated by cgit v1.2.3 (git 2.39.1) at 2024-09-30 12:33:12 +0000