diff options
Diffstat (limited to 'epan/dissectors/packet-socketcan.c')
| -rw-r--r-- | epan/dissectors/packet-socketcan.c | 949 |
1 files changed, 949 insertions, 0 deletions
diff --git a/epan/dissectors/packet-socketcan.c b/epan/dissectors/packet-socketcan.c new file mode 100644 index 0000000..90cf2bf --- /dev/null +++ b/epan/dissectors/packet-socketcan.c @@ -0,0 +1,949 @@ +/* packet-socketcan.c + * Routines for disassembly of packets from SocketCAN + * Felix Obenhuber <felix@obenhuber.de> + * + * Added support for the DeviceNet Dissector + * Hans-Joergen Gunnarsson <hag@hms.se> + * Copyright 2013 + * + * 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/prefs.h> +#include <epan/expert.h> +#include <epan/decode_as.h> +#include <epan/uat.h> +#include <wiretap/wtap.h> + +#include "packet-sll.h" +#include "packet-socketcan.h" + +void proto_register_socketcan(void); +void proto_reg_handoff_socketcan(void); + +static int hf_can_len = -1; +static int hf_can_infoent_ext = -1; +static int hf_can_infoent_std = -1; +static int hf_can_extflag = -1; +static int hf_can_rtrflag = -1; +static int hf_can_errflag = -1; +static int hf_can_reserved = -1; +static int hf_can_padding = -1; + +static int hf_can_err_tx_timeout = -1; +static int hf_can_err_lostarb = -1; +static int hf_can_err_ctrl = -1; +static int hf_can_err_prot = -1; +static int hf_can_err_trx = -1; +static int hf_can_err_ack = -1; +static int hf_can_err_busoff = -1; +static int hf_can_err_buserror = -1; +static int hf_can_err_restarted = -1; +static int hf_can_err_reserved = -1; + +static int hf_can_err_lostarb_bit_number = -1; + +static int hf_can_err_ctrl_rx_overflow = -1; +static int hf_can_err_ctrl_tx_overflow = -1; +static int hf_can_err_ctrl_rx_warning = -1; +static int hf_can_err_ctrl_tx_warning = -1; +static int hf_can_err_ctrl_rx_passive = -1; +static int hf_can_err_ctrl_tx_passive = -1; +static int hf_can_err_ctrl_active = -1; + +static int hf_can_err_prot_error_type_bit = -1; +static int hf_can_err_prot_error_type_form = -1; +static int hf_can_err_prot_error_type_stuff = -1; +static int hf_can_err_prot_error_type_bit0 = -1; +static int hf_can_err_prot_error_type_bit1 = -1; +static int hf_can_err_prot_error_type_overload = -1; +static int hf_can_err_prot_error_type_active = -1; +static int hf_can_err_prot_error_type_tx = -1; + +static int hf_can_err_prot_error_location = -1; + +static int hf_can_err_trx_canh = -1; +static int hf_can_err_trx_canl = -1; + +static int hf_can_err_ctrl_specific = -1; + +static expert_field ei_can_err_dlc_mismatch = EI_INIT; + +static int hf_canfd_brsflag = -1; +static int hf_canfd_esiflag = -1; + +static gint ett_can = -1; +static gint ett_can_fd = -1; + +static int proto_can = -1; +static int proto_canfd = -1; + +static gboolean byte_swap = FALSE; +static gboolean heuristic_first = FALSE; + +static heur_dissector_list_t heur_subdissector_list; +static heur_dtbl_entry_t *heur_dtbl_entry; + +#define LINUX_CAN_STD 0 +#define LINUX_CAN_EXT 1 +#define LINUX_CAN_ERR 2 + +#define CAN_LEN_OFFSET 4 +#define CAN_DATA_OFFSET 8 + +#define CANFD_FLAG_OFFSET 5 + +#define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */ +#define CANFD_ESI 0x02 /* error state indicator of the transmitting node */ + +static dissector_table_t can_id_dissector_table = NULL; +static dissector_table_t can_extended_id_dissector_table = NULL; +static dissector_table_t subdissector_table = NULL; +static dissector_handle_t socketcan_classic_handle; +static dissector_handle_t socketcan_fd_handle; +static dissector_handle_t socketcan_bigendian_handle; + + +static const value_string can_err_prot_error_location_vals[] = { + { 0x00, "unspecified" }, + { 0x02, "ID bits 28 - 21 (SFF: 10 - 3)" }, + { 0x03, "start of frame" }, + { 0x04, "substitute RTR (SFF: RTR)" }, + { 0x05, "identifier extension" }, + { 0x06, "ID bits 20 - 18 (SFF: 2 - 0)" }, + { 0x07, "ID bits 17-13" }, + { 0x08, "CRC sequence" }, + { 0x09, "reserved bit 0" }, + { 0x0A, "data section" }, + { 0x0B, "data length code" }, + { 0x0C, "RTR" }, + { 0x0D, "reserved bit 1" }, + { 0x0E, "ID bits 4-0" }, + { 0x0F, "ID bits 12-5" }, + { 0x12, "intermission" }, + { 0x18, "CRC delimiter" }, + { 0x19, "ACK slot" }, + { 0x1A, "end of frame" }, + { 0x1B, "ACK delimiter" }, + { 0, NULL } +}; + +static const value_string can_err_trx_canh_vals[] = { + { 0x00, "unspecified" }, + { 0x04, "no wire" }, + { 0x05, "short to BAT" }, + { 0x06, "short to VCC" }, + { 0x07, "short to GND" }, + { 0, NULL } +}; + +static const value_string can_err_trx_canl_vals[] = { + { 0x00, "unspecified" }, + { 0x04, "no wire" }, + { 0x05, "short to BAT" }, + { 0x06, "short to VCC" }, + { 0x07, "short to GND" }, + { 0x08, "short to CANH" }, + { 0, NULL } +}; + +/********* UATs *********/ + +/* Interface Config UAT */ +typedef struct _interface_config { + guint interface_id; + gchar *interface_name; + guint bus_id; +} interface_config_t; + +#define DATAFILE_CAN_INTERFACE_MAPPING "CAN_interface_mapping" + +static GHashTable *data_can_interfaces_by_id = NULL; +static GHashTable *data_can_interfaces_by_name = NULL; +static interface_config_t *interface_configs = NULL; +static guint interface_config_num = 0; + +UAT_HEX_CB_DEF(interface_configs, interface_id, interface_config_t) +UAT_CSTRING_CB_DEF(interface_configs, interface_name, interface_config_t) +UAT_HEX_CB_DEF(interface_configs, bus_id, interface_config_t) + +static void * +copy_interface_config_cb(void *n, const void *o, size_t size _U_) { + interface_config_t *new_rec = (interface_config_t *)n; + const interface_config_t *old_rec = (const interface_config_t *)o; + + new_rec->interface_id = old_rec->interface_id; + new_rec->interface_name = g_strdup(old_rec->interface_name); + new_rec->bus_id = old_rec->bus_id; + return new_rec; +} + +static bool +update_interface_config(void *r, char **err) { + interface_config_t *rec = (interface_config_t *)r; + + if (rec->interface_id > 0xffffffff) { + *err = ws_strdup_printf("We currently only support 32 bit identifiers (ID: %i Name: %s)", + rec->interface_id, rec->interface_name); + return FALSE; + } + + if (rec->bus_id > 0xffff) { + *err = ws_strdup_printf("We currently only support 16 bit bus identifiers (ID: %i Name: %s Bus-ID: %i)", + rec->interface_id, rec->interface_name, rec->bus_id); + return FALSE; + } + + return TRUE; +} + +static void +free_interface_config_cb(void *r) { + interface_config_t *rec = (interface_config_t *)r; + + /* freeing result of g_strdup */ + g_free(rec->interface_name); + rec->interface_name = NULL; +} + +static interface_config_t * +ht_lookup_interface_config_by_id(unsigned int identifier) { + interface_config_t *tmp = NULL; + unsigned int *id = NULL; + + if (interface_configs == NULL) { + return NULL; + } + + id = wmem_new(wmem_epan_scope(), unsigned int); + *id = (unsigned int)identifier; + tmp = (interface_config_t *)g_hash_table_lookup(data_can_interfaces_by_id, id); + wmem_free(wmem_epan_scope(), id); + + return tmp; +} + +static interface_config_t * +ht_lookup_interface_config_by_name(const gchar *name) { + interface_config_t *tmp = NULL; + gchar *key = NULL; + + if (interface_configs == NULL) { + return NULL; + } + + key = wmem_strdup(wmem_epan_scope(), name); + tmp = (interface_config_t *)g_hash_table_lookup(data_can_interfaces_by_name, key); + wmem_free(wmem_epan_scope(), key); + + return tmp; +} + +static void +can_free_key(gpointer key) { + wmem_free(wmem_epan_scope(), key); +} + +static void +post_update_can_interfaces_cb(void) { + guint i; + int *key_id = NULL; + gchar *key_name = NULL; + + /* destroy old hash tables, if they exist */ + if (data_can_interfaces_by_id) { + g_hash_table_destroy(data_can_interfaces_by_id); + data_can_interfaces_by_id = NULL; + } + if (data_can_interfaces_by_name) { + g_hash_table_destroy(data_can_interfaces_by_name); + data_can_interfaces_by_name = NULL; + } + + /* create new hash table */ + data_can_interfaces_by_id = g_hash_table_new_full(g_int_hash, g_int_equal, &can_free_key, NULL); + data_can_interfaces_by_name = g_hash_table_new_full(g_str_hash, g_str_equal, &can_free_key, NULL); + + if (data_can_interfaces_by_id == NULL || data_can_interfaces_by_name == NULL || interface_configs == NULL || interface_config_num == 0) { + return; + } + + for (i = 0; i < interface_config_num; i++) { + if (interface_configs[i].interface_id != 0xfffffff) { + key_id = wmem_new(wmem_epan_scope(), int); + *key_id = interface_configs[i].interface_id; + g_hash_table_insert(data_can_interfaces_by_id, key_id, &interface_configs[i]); + } + + if (interface_configs[i].interface_name != NULL && interface_configs[i].interface_name[0] != 0) { + key_name = wmem_strdup(wmem_epan_scope(), interface_configs[i].interface_name); + g_hash_table_insert(data_can_interfaces_by_name, key_name, &interface_configs[i]); + } + } +} + +/* We match based on the config in the following order: + * - interface_name matches and interface_id matches + * - interface_name matches and interface_id = 0xffffffff + * - interface_name = "" and interface_id matches + */ +static guint +get_bus_id(packet_info *pinfo) { + guint32 interface_id = pinfo->rec->rec_header.packet_header.interface_id; + const char *interface_name = epan_get_interface_name(pinfo->epan, interface_id); + interface_config_t *tmp = NULL; + + if (!(pinfo->rec->presence_flags & WTAP_HAS_INTERFACE_ID)) { + return 0; + } + + if (interface_name != NULL && interface_name[0] != 0) { + tmp = ht_lookup_interface_config_by_name(interface_name); + + if (tmp != NULL && (tmp->interface_id == 0xffffffff || tmp->interface_id == interface_id)) { + /* name + id match or name match and id = any */ + return tmp->bus_id; + } + + tmp = ht_lookup_interface_config_by_id(interface_id); + + if (tmp != NULL && (tmp->interface_name == NULL || tmp->interface_name[0] == 0)) { + /* id matches and name is any */ + return tmp->bus_id; + } + } + + /* we found nothing */ + return 0; +} + +/* Senders and Receivers UAT */ +typedef struct _sender_receiver_config { + guint bus_id; + guint can_id; + gchar *sender_name; + gchar *receiver_name; +} sender_receiver_config_t; + +#define DATAFILE_CAN_SENDER_RECEIVER "CAN_senders_receivers" + +static GHashTable *data_sender_receiver = NULL; +static sender_receiver_config_t *sender_receiver_configs = NULL; +static guint sender_receiver_config_num = 0; + +UAT_HEX_CB_DEF(sender_receiver_configs, bus_id, sender_receiver_config_t) +UAT_HEX_CB_DEF(sender_receiver_configs, can_id, sender_receiver_config_t) +UAT_CSTRING_CB_DEF(sender_receiver_configs, sender_name, sender_receiver_config_t) +UAT_CSTRING_CB_DEF(sender_receiver_configs, receiver_name, sender_receiver_config_t) + +static void * +copy_sender_receiver_config_cb(void *n, const void *o, size_t size _U_) { + sender_receiver_config_t *new_rec = (sender_receiver_config_t *)n; + const sender_receiver_config_t *old_rec = (const sender_receiver_config_t *)o; + + new_rec->bus_id = old_rec->bus_id; + new_rec->can_id = old_rec->can_id; + new_rec->sender_name = g_strdup(old_rec->sender_name); + new_rec->receiver_name = g_strdup(old_rec->receiver_name); + return new_rec; +} + +static bool +update_sender_receiver_config(void *r, char **err) { + sender_receiver_config_t *rec = (sender_receiver_config_t *)r; + + if (rec->bus_id > 0xffff) { + *err = ws_strdup_printf("We currently only support 16 bit bus identifiers (Bus ID: %i CAN ID: %i)", rec->bus_id, rec->can_id); + return FALSE; + } + + return TRUE; +} + +static void +free_sender_receiver_config_cb(void *r) { + sender_receiver_config_t *rec = (sender_receiver_config_t *)r; + + /* freeing result of g_strdup */ + g_free(rec->sender_name); + rec->sender_name = NULL; + g_free(rec->receiver_name); + rec->receiver_name = NULL; +} + +static guint64 +sender_receiver_key(guint16 bus_id, guint32 can_id) { + return ((guint64)bus_id << 32) | can_id; +} + +static sender_receiver_config_t * +ht_lookup_sender_receiver_config(guint16 bus_id, guint32 can_id) { + sender_receiver_config_t *tmp = NULL; + guint64 key = 0; + + if (sender_receiver_configs == NULL) { + return NULL; + } + + key = sender_receiver_key(bus_id, can_id); + tmp = (sender_receiver_config_t *)g_hash_table_lookup(data_sender_receiver, &key); + + if (tmp == NULL) { + key = sender_receiver_key(0, can_id); + tmp = (sender_receiver_config_t *)g_hash_table_lookup(data_sender_receiver, &key); + } + + return tmp; +} + +static void +sender_receiver_free_key(gpointer key) { + wmem_free(wmem_epan_scope(), key); +} + +static void +post_update_sender_receiver_cb(void) { + guint i; + guint64 *key_id = NULL; + + /* destroy old hash table, if it exist */ + if (data_sender_receiver) { + g_hash_table_destroy(data_sender_receiver); + data_sender_receiver = NULL; + } + + /* create new hash table */ + data_sender_receiver = g_hash_table_new_full(g_int64_hash, g_int64_equal, &sender_receiver_free_key, NULL); + + if (data_sender_receiver == NULL || sender_receiver_configs == NULL || sender_receiver_config_num == 0) { + return; + } + + for (i = 0; i < sender_receiver_config_num; i++) { + key_id = wmem_new(wmem_epan_scope(), guint64); + *key_id = sender_receiver_key(sender_receiver_configs[i].bus_id, sender_receiver_configs[i].can_id); + g_hash_table_insert(data_sender_receiver, key_id, &sender_receiver_configs[i]); + } +} + +gboolean +socketcan_set_source_and_destination_columns(packet_info *pinfo, can_info_t *caninfo) { + sender_receiver_config_t *tmp = ht_lookup_sender_receiver_config(caninfo->bus_id, caninfo->id); + + if (tmp != NULL) { + /* remove all addresses to support CAN as payload (e.g., TECMP) */ + clear_address(&pinfo->net_src); + clear_address(&pinfo->dl_src); + clear_address(&pinfo->src); + clear_address(&pinfo->net_dst); + clear_address(&pinfo->dl_dst); + clear_address(&pinfo->dst); + + col_add_fstr(pinfo->cinfo, COL_DEF_SRC, "%s", tmp->sender_name); + col_add_fstr(pinfo->cinfo, COL_DEF_DST, "%s", tmp->receiver_name); + return true; + } + return false; +} + +gboolean +socketcan_call_subdissectors(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, struct can_info *can_info, const gboolean use_heuristics_first) { + dissector_table_t effective_can_id_dissector_table = (can_info->id & CAN_EFF_FLAG) ? can_extended_id_dissector_table : can_id_dissector_table; + guint32 effective_can_id = (can_info->id & CAN_EFF_FLAG) ? can_info->id & CAN_EFF_MASK : can_info->id & CAN_SFF_MASK; + + if (!dissector_try_uint_new(effective_can_id_dissector_table, effective_can_id, tvb, pinfo, tree, TRUE, can_info)) { + if (!use_heuristics_first) { + if (!dissector_try_payload_new(subdissector_table, tvb, pinfo, tree, TRUE, can_info)) { + if (!dissector_try_heuristic(heur_subdissector_list, tvb, pinfo, tree, &heur_dtbl_entry, can_info)) { + return FALSE; + } + } + } else { + if (!dissector_try_heuristic(heur_subdissector_list, tvb, pinfo, tree, &heur_dtbl_entry, can_info)) { + if (!dissector_try_payload_new(subdissector_table, tvb, pinfo, tree, FALSE, can_info)) { + return FALSE; + } + } + } + } + + return TRUE; +} + +/* + * Either: + * + * 1) a given SocketCAN frame is known to contain a classic CAN + * packet based on information outside the SocketCAN header; + * + * 2) a given SocketCAN frame is known to contain a CAN FD + * packet based on information outside the SocketCAN header; + * + * 3) we don't know whether the given SocketCAN frame is a + * classic CAN packet or a CAN FD packet, and will have + * to check the CANFD_FDF bit in the "FD flags" field of + * the SocketCAN header to determine that. + */ +typedef enum { + PACKET_TYPE_CAN, + PACKET_TYPE_CAN_FD, + PACKET_TYPE_UNKNOWN +} can_packet_type_t; + +static int +dissect_socketcan_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint encoding, can_packet_type_t can_packet_type) { + proto_tree *can_tree; + proto_item *ti; + guint8 frame_type; + can_info_t can_info; + int * const *can_flags; + + static int * const can_std_flags[] = { + &hf_can_infoent_std, + &hf_can_extflag, + &hf_can_rtrflag, + &hf_can_errflag, + NULL, + }; + static int * const can_ext_flags[] = { + &hf_can_infoent_ext, + &hf_can_extflag, + &hf_can_rtrflag, + &hf_can_errflag, + NULL, + }; + static int * const can_std_flags_fd[] = { + &hf_can_infoent_std, + &hf_can_extflag, + NULL, + }; + static int * const can_ext_flags_fd[] = { + &hf_can_infoent_ext, + &hf_can_extflag, + NULL, + }; + static int * const canfd_flag_fields[] = { + &hf_canfd_brsflag, + &hf_canfd_esiflag, + NULL, + }; + static int * const can_err_flags[] = { + &hf_can_errflag, + &hf_can_err_tx_timeout, + &hf_can_err_lostarb, + &hf_can_err_ctrl, + &hf_can_err_prot, + &hf_can_err_trx, + &hf_can_err_ack, + &hf_can_err_busoff, + &hf_can_err_buserror, + &hf_can_err_restarted, + &hf_can_err_reserved, + NULL, + }; + + can_info.id = tvb_get_guint32(tvb, 0, encoding); + can_info.len = tvb_get_guint8(tvb, CAN_LEN_OFFSET); + + /* + * If we weren't told the type of this frame, check + * whether the CANFD_FDF flag is set in the FD flags + * field of the header; if so, it's a CAN FD frame. + * otherwise, it's a CAN frame. + * + * However, trust the CANFD_FDF flag only if the only + * bits set in the FD flags field are the known bits, + * and the two bytes following that field are both + * zero. This is because some older LINKTYPE_CAN_SOCKETCAN + * frames had uninitialized junk in the FD flags field, + * so we treat a frame with what appears to be uninitialized + * junk as being CAN rather than CAN FD, under the assumption + * that the CANFD_FDF bit is set because the field is + * uninitialized, not because it was explicitly set because + * it's a CAN FD frame. At least some newer code that sets + * that flag also makes sure that the fields in question are + * initialized, so we assume that if they're not initialized + * the code is older code that didn't support CAN FD. + */ + if (can_packet_type == PACKET_TYPE_UNKNOWN) { + guint8 fd_flags; + + fd_flags = tvb_get_guint8(tvb, CANFD_FLAG_OFFSET); + + if ((fd_flags & CANFD_FDF) && ((fd_flags & ~(CANFD_BRS | CANFD_ESI | CANFD_FDF)) == 0) && + tvb_get_guint8(tvb, CANFD_FLAG_OFFSET + 1) == 0 && + tvb_get_guint8(tvb, CANFD_FLAG_OFFSET + 2) == 0) { + can_packet_type = PACKET_TYPE_CAN_FD; + } else { + can_packet_type = PACKET_TYPE_CAN; + } + } + + can_info.fd = (can_packet_type == PACKET_TYPE_CAN_FD); + can_info.bus_id = get_bus_id(pinfo); + + /* Error Message Frames are only encapsulated in Classic CAN frames */ + if (can_packet_type == PACKET_TYPE_CAN && (can_info.id & CAN_ERR_FLAG)) { + frame_type = LINUX_CAN_ERR; + can_flags = can_err_flags; + } else if (can_info.id & CAN_EFF_FLAG) { + frame_type = LINUX_CAN_EXT; + can_info.id &= (CAN_EFF_MASK | CAN_FLAG_MASK); + can_flags = (can_packet_type == PACKET_TYPE_CAN_FD) ? can_ext_flags_fd : can_ext_flags; + } else { + frame_type = LINUX_CAN_STD; + can_info.id &= (CAN_SFF_MASK | CAN_FLAG_MASK); + can_flags = (can_packet_type == PACKET_TYPE_CAN_FD) ? can_std_flags_fd : can_std_flags; + } + + col_set_str(pinfo->cinfo, COL_PROTOCOL, (can_packet_type == PACKET_TYPE_CAN_FD) ? "CANFD" : "CAN"); + col_clear(pinfo->cinfo, COL_INFO); + + guint32 effective_can_id = (can_info.id & CAN_EFF_FLAG) ? can_info.id & CAN_EFF_MASK : can_info.id & CAN_SFF_MASK; + char *id_name = (can_info.id & CAN_EFF_FLAG) ? "Ext. ID" : "ID"; + col_add_fstr(pinfo->cinfo, COL_INFO, "%s: %d (0x%" PRIx32 "), Length: %d", id_name, effective_can_id, effective_can_id, can_info.len); + + socketcan_set_source_and_destination_columns(pinfo, &can_info); + + ti = proto_tree_add_item(tree, (can_packet_type == PACKET_TYPE_CAN_FD) ? proto_canfd : proto_can, tvb, 0, -1, ENC_NA); + can_tree = proto_item_add_subtree(ti, (can_packet_type == PACKET_TYPE_CAN_FD) ? ett_can_fd : ett_can); + + proto_item_append_text(can_tree, ", %s: %d (0x%" PRIx32 "), Length: %d", id_name, effective_can_id, effective_can_id, can_info.len); + + proto_tree_add_bitmask_list(can_tree, tvb, 0, 4, can_flags, encoding); + proto_tree_add_item(can_tree, hf_can_len, tvb, CAN_LEN_OFFSET, 1, ENC_NA); + + if (frame_type == LINUX_CAN_ERR && can_info.len != CAN_ERR_DLC) { + proto_tree_add_expert(tree, pinfo, &ei_can_err_dlc_mismatch, tvb, CAN_LEN_OFFSET, 1); + } + + if (can_packet_type == PACKET_TYPE_CAN_FD) { + proto_tree_add_bitmask_list(can_tree, tvb, CANFD_FLAG_OFFSET, 1, canfd_flag_fields, ENC_NA); + proto_tree_add_item(can_tree, hf_can_reserved, tvb, CANFD_FLAG_OFFSET+1, 2, ENC_NA); + } else { + proto_tree_add_item(can_tree, hf_can_reserved, tvb, CANFD_FLAG_OFFSET, 3, ENC_NA); + } + + if (frame_type == LINUX_CAN_ERR) { + int * const *flag; + const char *sepa = ": "; + + col_set_str(pinfo->cinfo, COL_INFO, "ERR"); + + for (flag = can_err_flags; *flag; flag++) { + header_field_info *hfi; + + hfi = proto_registrar_get_nth(**flag); + if (!hfi) + continue; + + if ((can_info.id & hfi->bitmask & ~CAN_FLAG_MASK) == 0) + continue; + + col_append_sep_str(pinfo->cinfo, COL_INFO, sepa, hfi->name); + sepa = ", "; + } + + if (can_info.id & CAN_ERR_LOSTARB) { + proto_tree_add_item(can_tree, hf_can_err_lostarb_bit_number, tvb, CAN_DATA_OFFSET + 0, 1, ENC_NA); + } + + if (can_info.id & CAN_ERR_CTRL) { + static int * const can_err_ctrl_flags[] = { + &hf_can_err_ctrl_rx_overflow, + &hf_can_err_ctrl_tx_overflow, + &hf_can_err_ctrl_rx_warning, + &hf_can_err_ctrl_tx_warning, + &hf_can_err_ctrl_rx_passive, + &hf_can_err_ctrl_tx_passive, + &hf_can_err_ctrl_active, + NULL, + }; + + proto_tree_add_bitmask_list(can_tree, tvb, CAN_DATA_OFFSET+1, 1, can_err_ctrl_flags, ENC_NA); + } + + if (can_info.id & CAN_ERR_PROT) { + static int * const can_err_prot_error_type_flags[] = { + &hf_can_err_prot_error_type_bit, + &hf_can_err_prot_error_type_form, + &hf_can_err_prot_error_type_stuff, + &hf_can_err_prot_error_type_bit0, + &hf_can_err_prot_error_type_bit1, + &hf_can_err_prot_error_type_overload, + &hf_can_err_prot_error_type_active, + &hf_can_err_prot_error_type_tx, + NULL + }; + proto_tree_add_bitmask_list(can_tree, tvb, CAN_DATA_OFFSET+2, 1, can_err_prot_error_type_flags, ENC_NA); + proto_tree_add_item(can_tree, hf_can_err_prot_error_location, tvb, CAN_DATA_OFFSET+3, 1, ENC_NA); + } + + if (can_info.id & CAN_ERR_TRX) { + proto_tree_add_item(can_tree, hf_can_err_trx_canh, tvb, CAN_DATA_OFFSET+4, 1, ENC_NA); + proto_tree_add_item(can_tree, hf_can_err_trx_canl, tvb, CAN_DATA_OFFSET+4, 1, ENC_NA); + } + + proto_tree_add_item(can_tree, hf_can_err_ctrl_specific, tvb, CAN_DATA_OFFSET+5, 3, ENC_NA); + } else { + tvbuff_t *next_tvb; + + if (can_info.id & CAN_RTR_FLAG) { + col_append_str(pinfo->cinfo, COL_INFO, "(Remote Transmission Request)"); + } + + next_tvb = tvb_new_subset_length(tvb, CAN_DATA_OFFSET, can_info.len); + + if (!socketcan_call_subdissectors(next_tvb, pinfo, tree, &can_info, heuristic_first)) { + call_data_dissector(next_tvb, pinfo, tree); + } + } + + if (tvb_captured_length_remaining(tvb, CAN_DATA_OFFSET+can_info.len) > 0) { + proto_tree_add_item(can_tree, hf_can_padding, tvb, CAN_DATA_OFFSET+can_info.len, -1, ENC_NA); + } + + return tvb_captured_length(tvb); +} + +static int +dissect_socketcan_bigendian(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { + return dissect_socketcan_common(tvb, pinfo, tree, + byte_swap ? ENC_LITTLE_ENDIAN : ENC_BIG_ENDIAN, PACKET_TYPE_UNKNOWN); +} + +static int +dissect_socketcan_classic(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { + return dissect_socketcan_common(tvb, pinfo, tree, + byte_swap ? ENC_ANTI_HOST_ENDIAN : ENC_HOST_ENDIAN, PACKET_TYPE_CAN); +} + +static int +dissect_socketcan_fd(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { + return dissect_socketcan_common(tvb, pinfo, tree, + byte_swap ? ENC_ANTI_HOST_ENDIAN : ENC_HOST_ENDIAN, PACKET_TYPE_CAN_FD); +} + +void +proto_register_socketcan(void) { + static hf_register_info hf[] = { + { &hf_can_infoent_ext, { + "ID", "can.id", FT_UINT32, BASE_DEC_HEX, NULL, CAN_EFF_MASK, NULL, HFILL } }, + { &hf_can_infoent_std, { + "ID", "can.id", FT_UINT32, BASE_DEC_HEX, NULL, CAN_SFF_MASK, NULL, HFILL } }, + { &hf_can_extflag, { + "Extended Flag", "can.flags.xtd", FT_BOOLEAN, 32, NULL, CAN_EFF_FLAG, NULL, HFILL } }, + { &hf_can_rtrflag, { + "Remote Transmission Request Flag", "can.flags.rtr", FT_BOOLEAN, 32, NULL, CAN_RTR_FLAG, NULL, HFILL } }, + { &hf_can_errflag, { + "Error Message Flag", "can.flags.err", FT_BOOLEAN, 32, NULL, CAN_ERR_FLAG, NULL, HFILL } }, + { &hf_can_len, { + "Frame-Length", "can.len", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } }, + { &hf_can_reserved, { + "Reserved", "can.reserved", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, + { &hf_can_padding, { + "Padding", "can.padding", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, + { &hf_canfd_brsflag, { + "Bit Rate Setting", "canfd.flags.brs", FT_BOOLEAN, 8, NULL, CANFD_BRS, NULL, HFILL } }, + { &hf_canfd_esiflag, { + "Error State Indicator", "canfd.flags.esi", FT_BOOLEAN, 8, NULL, CANFD_ESI, NULL, HFILL } }, + { &hf_can_err_tx_timeout, { + "Transmit timeout", "can.err.tx_timeout", FT_BOOLEAN, 32, NULL, CAN_ERR_TX_TIMEOUT, NULL, HFILL } }, + { &hf_can_err_lostarb, { + "Lost arbitration", "can.err.lostarb", FT_BOOLEAN, 32, NULL, CAN_ERR_LOSTARB, NULL, HFILL } }, + { &hf_can_err_ctrl, { + "Controller problems", "can.err.ctrl", FT_BOOLEAN, 32, NULL, CAN_ERR_CTRL, NULL, HFILL } }, + { &hf_can_err_prot, { + "Protocol violation", "can.err.prot", FT_BOOLEAN, 32, NULL, CAN_ERR_PROT, NULL, HFILL } }, + { &hf_can_err_trx, { + "Transceiver status", "can.err.trx", FT_BOOLEAN, 32, NULL, CAN_ERR_TRX, NULL, HFILL } }, + { &hf_can_err_ack, { + "No acknowledgment", "can.err.ack", FT_BOOLEAN, 32, NULL, CAN_ERR_ACK, NULL, HFILL } }, + { &hf_can_err_busoff, { + "Bus off", "can.err.busoff", FT_BOOLEAN, 32, NULL, CAN_ERR_BUSOFF, NULL, HFILL } }, + { &hf_can_err_buserror, { + "Bus error", "can.err.buserror", FT_BOOLEAN, 32, NULL, CAN_ERR_BUSERROR, NULL, HFILL } }, + { &hf_can_err_restarted, { + "Controller restarted", "can.err.restarted", FT_BOOLEAN, 32, NULL, CAN_ERR_RESTARTED, NULL, HFILL } }, + { &hf_can_err_reserved, { + "Reserved", "can.err.reserved", FT_UINT32, BASE_HEX, NULL, CAN_ERR_RESERVED, NULL, HFILL } }, + { &hf_can_err_lostarb_bit_number, { + "Lost arbitration in bit number", "can.err.lostarb.bitnum", FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL } }, + { &hf_can_err_ctrl_rx_overflow, { + "RX buffer overflow", "can.err.ctrl.rx_overflow", FT_BOOLEAN, 8, NULL, 0x01, NULL, HFILL } }, + { &hf_can_err_ctrl_tx_overflow, { + "TX buffer overflow", "can.err.ctrl.tx_overflow", FT_BOOLEAN, 8, NULL, 0x02, NULL, HFILL } }, + { &hf_can_err_ctrl_rx_warning, { + "Reached warning level for RX errors", "can.err.ctrl.rx_warning", FT_BOOLEAN, 8, NULL, 0x04, NULL, HFILL } }, + { &hf_can_err_ctrl_tx_warning, { + "Reached warning level for TX errors", "can.err.ctrl.tx_warning", FT_BOOLEAN, 8, NULL, 0x08, NULL, HFILL } }, + { &hf_can_err_ctrl_rx_passive, { + "Reached error passive status RX", "can.err.ctrl.rx_passive", FT_BOOLEAN, 8, NULL, 0x10, NULL, HFILL } }, + { &hf_can_err_ctrl_tx_passive, { + "Reached error passive status TX", "can.err.ctrl.tx_passive", FT_BOOLEAN, 8, NULL, 0x20, NULL, HFILL } }, + { &hf_can_err_ctrl_active, { + "Recovered to error active state", "can.err.ctrl.active", FT_BOOLEAN, 8, NULL, 0x40, NULL, HFILL } }, + { &hf_can_err_prot_error_type_bit, { + "Single bit error", "can.err.prot.type.bit", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_BIT, NULL, HFILL } }, + { &hf_can_err_prot_error_type_form, { + "Frame format error", "can.err.prot.type.form", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_FORM, NULL, HFILL } }, + { &hf_can_err_prot_error_type_stuff, { + "Bit stuffing error", "can.err.prot.type.stuff", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_STUFF, NULL, HFILL } }, + { &hf_can_err_prot_error_type_bit0, { + "Unable to send dominant bit", "can.err.prot.type.bit0", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_BIT0, NULL, HFILL } }, + { &hf_can_err_prot_error_type_bit1, { + "Unable to send recessive bit", "can.err.prot.type.bit1", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_BIT1, NULL, HFILL } }, + { &hf_can_err_prot_error_type_overload, { + "Bus overload", "can.err.prot.type.overload", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_OVERLOAD, NULL, HFILL } }, + { &hf_can_err_prot_error_type_active, { + "Active error announcement", "can.err.prot.type.active", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_ACTIVE, NULL, HFILL } }, + { &hf_can_err_prot_error_type_tx, { + "Error occurred on transmission", "can.err.prot.type.tx", FT_BOOLEAN, 8, NULL, CAN_ERR_PROT_TX, NULL, HFILL } }, + { &hf_can_err_prot_error_location, { + "Protocol error location", "can.err.prot.location", FT_UINT8, BASE_DEC, VALS(can_err_prot_error_location_vals), 0, NULL, HFILL } }, + { &hf_can_err_trx_canh, { + "Transceiver CANH status", "can.err.trx.canh", FT_UINT8, BASE_DEC, VALS(can_err_trx_canh_vals), 0x0F, NULL, HFILL } }, + { &hf_can_err_trx_canl, { + "Transceiver CANL status", "can.err.trx.canl", FT_UINT8, BASE_DEC, VALS(can_err_trx_canl_vals), 0xF0, NULL, HFILL } }, + { &hf_can_err_ctrl_specific, { + "Controller specific data", "can.err.ctrl_specific", FT_BYTES, SEP_SPACE, NULL, 0, NULL, HFILL } }, + }; + + uat_t *can_interface_uat = NULL; + uat_t *sender_receiver_uat = NULL; + + /* Setup protocol subtree array */ + static gint *ett[] = { + &ett_can, + &ett_can_fd + }; + + static ei_register_info ei[] = { + { &ei_can_err_dlc_mismatch, { + "can.err.dlc_mismatch", PI_MALFORMED, PI_ERROR, "ERROR: DLC mismatch", EXPFILL } } + }; + + module_t *can_module; + + proto_can = proto_register_protocol("Controller Area Network", "CAN", "can"); + + /* + * "can-hostendian" is a legacy name (there never was, in any libpcap + * release, a SocketCAN LINKTYPE_ value for a host-endian CAN ID + * and flags field); we need to keep it around in case some candump + * or Busmaster capture that was saved as a pcap or pcapng file, + * as those use a linktype of LINKTYPE_WIRESHARK_UPPER_PDU with + * "can-hostendian" as the dissector name. + */ + socketcan_classic_handle = register_dissector("can-hostendian", dissect_socketcan_classic, proto_can); + socketcan_bigendian_handle = register_dissector("can-bigendian", dissect_socketcan_bigendian, proto_can); + + proto_canfd = proto_register_protocol("Controller Area Network FD", "CANFD", "canfd"); + socketcan_fd_handle = register_dissector("canfd", dissect_socketcan_fd, proto_canfd); + + proto_register_field_array(proto_can, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + expert_register_field_array(expert_register_protocol(proto_can), ei, array_length(ei)); + + can_module = prefs_register_protocol(proto_can, NULL); + + prefs_register_obsolete_preference(can_module, "protocol"); + + prefs_register_bool_preference(can_module, "byte_swap", "Byte-swap the CAN ID/flags field", + "Whether the CAN ID/flags field should be byte-swapped", + &byte_swap); + + prefs_register_bool_preference(can_module, "try_heuristic_first", "Try heuristic sub-dissectors first", + "Try to decode a packet using an heuristic sub-dissector before using a sub-dissector registered to \"decode as\"", + &heuristic_first); + + can_id_dissector_table = register_dissector_table("can.id", "CAN ID", proto_can, FT_UINT32, BASE_DEC); + + can_extended_id_dissector_table = register_dissector_table("can.extended_id", "CAN Extended ID", proto_can, FT_UINT32, BASE_DEC); + + subdissector_table = register_decode_as_next_proto(proto_can, "can.subdissector", "CAN next level dissector", NULL); + + heur_subdissector_list = register_heur_dissector_list("can", proto_can); + + static uat_field_t can_interface_mapping_uat_fields[] = { + UAT_FLD_HEX(interface_configs, interface_id, "Interface ID", "ID of the Interface with 0xffffffff = any (hex uint32 without leading 0x)"), + UAT_FLD_CSTRING(interface_configs, interface_name, "Interface Name", "Name of the Interface, empty = any (string)"), + UAT_FLD_HEX(interface_configs, bus_id, "Bus ID", "Bus ID of the Interface (hex uint16 without leading 0x)"), + UAT_END_FIELDS + }; + + can_interface_uat = uat_new("CAN Interface Mapping", + sizeof(interface_config_t), /* record size */ + DATAFILE_CAN_INTERFACE_MAPPING, /* filename */ + TRUE, /* from profile */ + (void**)&interface_configs, /* data_ptr */ + &interface_config_num, /* numitems_ptr */ + UAT_AFFECTS_DISSECTION, /* but not fields */ + NULL, /* help */ + copy_interface_config_cb, /* copy callback */ + update_interface_config, /* update callback */ + free_interface_config_cb, /* free callback */ + post_update_can_interfaces_cb, /* post update callback */ + NULL, /* reset callback */ + can_interface_mapping_uat_fields /* UAT field definitions */ + ); + + prefs_register_uat_preference(can_module, "_can_interface_mapping", "Interface Mapping", + "A table to define the mapping between interface and Bus ID.", can_interface_uat); + + static uat_field_t sender_receiver_mapping_uat_fields[] = { + UAT_FLD_HEX(sender_receiver_configs, bus_id, "Bus ID", "Bus ID of the Interface with 0 meaning any (hex uint16 without leading 0x)."), + UAT_FLD_HEX(sender_receiver_configs, can_id, "CAN ID", "ID of the CAN Message (hex uint32 without leading 0x)"), + UAT_FLD_CSTRING(sender_receiver_configs, sender_name, "Sender Name", "Name of Sender(s)"), + UAT_FLD_CSTRING(sender_receiver_configs, receiver_name, "Receiver Name", "Name of Receiver(s)"), + UAT_END_FIELDS + }; + + sender_receiver_uat = uat_new("Sender Receiver Config", + sizeof(sender_receiver_config_t), /* record size */ + DATAFILE_CAN_SENDER_RECEIVER, /* filename */ + TRUE, /* from profile */ + (void**)&sender_receiver_configs, /* data_ptr */ + &sender_receiver_config_num, /* numitems_ptr */ + UAT_AFFECTS_DISSECTION, /* but not fields */ + NULL, /* help */ + copy_sender_receiver_config_cb, /* copy callback */ + update_sender_receiver_config, /* update callback */ + free_sender_receiver_config_cb, /* free callback */ + post_update_sender_receiver_cb, /* post update callback */ + NULL, /* reset callback */ + sender_receiver_mapping_uat_fields /* UAT field definitions */ + ); + + prefs_register_uat_preference(can_module, "_sender_receiver_config", "Sender Receiver Config", + "A table to define the mapping between Bus ID and CAN ID to Sender and Receiver.", sender_receiver_uat); +} + +void +proto_reg_handoff_socketcan(void) { + dissector_add_uint("wtap_encap", WTAP_ENCAP_SOCKETCAN, socketcan_bigendian_handle); + + dissector_add_uint("sll.ltype", LINUX_SLL_P_CAN, socketcan_classic_handle); + dissector_add_uint("sll.ltype", LINUX_SLL_P_CANFD, socketcan_fd_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: + */ |