diff options
Diffstat (limited to 'epan/dissectors/packet-socketcan.c')
| -rw-r--r-- | epan/dissectors/packet-socketcan.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/epan/dissectors/packet-socketcan.c b/epan/dissectors/packet-socketcan.c index 0c4c2023ac..739cfb0f6e 100644 --- a/epan/dissectors/packet-socketcan.c +++ b/epan/dissectors/packet-socketcan.c @@ -19,6 +19,7 @@ #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" @@ -155,6 +156,176 @@ static const value_string can_err_trx_canl_vals[] = { 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 gboolean +update_interface_config(void *r, char **err) { + interface_config_t *rec = (interface_config_t *)r; + + if (rec->interface_id > 0xffffffff) { + *err = g_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 = g_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; +} + gboolean socketcan_call_subdissectors(tvbuff_t* tvb, packet_info* pinfo, proto_tree* tree, struct can_info* can_info, const gboolean use_heuristics_first) { @@ -229,6 +400,7 @@ dissect_socketcan_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gu can_info.id = tvb_get_guint32(tvb, 0, encoding); can_info.len = tvb_get_guint8(tvb, CAN_LEN_OFFSET); can_info.fd = FALSE; + can_info.bus_id = get_bus_id(pinfo); /* Error Message Frames are only encapsulated in Classic CAN frames */ if (can_info.id & CAN_ERR_FLAG) @@ -394,6 +566,7 @@ dissect_socketcanfd_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, can_info.id = tvb_get_guint32(tvb, 0, encoding); can_info.len = tvb_get_guint8(tvb, CAN_LEN_OFFSET); can_info.fd = TRUE; + can_info.bus_id = get_bus_id(pinfo); if (can_info.id & CAN_EFF_FLAG) { @@ -811,6 +984,7 @@ proto_register_socketcan(void) } }, }; + uat_t *can_interface_uat = NULL; /* Setup protocol subtree array */ static gint *ett[] = @@ -864,6 +1038,32 @@ proto_register_socketcan(void) 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); } void |