path: root/epan/dissectors/asn1/e2ap/packet-e2ap-template.c

/* packet-e2ap.c
 * Routines for E2APApplication Protocol (e2ap) packet dissection
 * Copyright 2021, Martin Mathieson
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 *
 * References: ORAN-WG3.E2AP-v03.00, ORAN-WG3.E2SM-KPM-v03.00, ORAN-WG3.E2SM-RC.03.00
 */

#include "config.h"

#include <epan/packet.h>
#include <epan/strutil.h>
#include <epan/asn1.h>
#include <epan/prefs.h>
#include <epan/sctpppids.h>
#include <epan/expert.h>
#include <epan/proto_data.h>
#include <epan/conversation.h>
#include <epan/to_str.h>
#include <epan/oids.h>

#include "packet-e2ap.h"
#include "packet-per.h"
#include "packet-ntp.h"

#define PNAME  "E2 Application Protocol"
#define PSNAME "E2AP"
#define PFNAME "e2ap"

/* Dissector will use SCTP PPID 70, 71 or 72 or SCTP port 37464. */
#define SCTP_PORT_E2AP 37464

void proto_register_e2ap(void);
void proto_reg_handoff_e2ap(void);

static dissector_handle_t e2ap_handle;

#include "packet-e2ap-val.h"

/* Initialize the protocol and registered fields */
static int proto_e2ap;
#include "packet-e2ap-hf.c"

static int hf_e2ap_unmapped_ran_function_id;
static int hf_e2ap_ran_function_name_not_recognised;
static int hf_e2ap_ran_function_setup_frame;

static int hf_e2ap_dissector_version;
static int hf_e2ap_frame_version;

static int hf_e2ap_timestamp_string;


/* Initialize the subtree pointers */
static gint ett_e2ap;

static expert_field ei_e2ap_ran_function_names_no_match;
static expert_field ei_e2ap_ran_function_id_not_mapped;
static expert_field ei_e2ap_ran_function_dissector_mismatch;
static expert_field ei_e2ap_ran_function_max_dissectors_registered;

#include "packet-e2ap-ett.c"


/* Forward declarations */
static int dissect_e2ap_RANfunction_Name(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_);


static int dissect_E2SM_KPM_EventTriggerDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_KPM_ActionDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_KPM_IndicationHeader_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_KPM_IndicationMessage_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_KPM_RANfunction_Description_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);

static int dissect_E2SM_RC_EventTrigger_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_ActionDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_RANFunctionDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_IndicationMessage_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_IndicationHeader_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_CallProcessID_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_ControlHeader_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_ControlMessage_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_RC_ControlOutcome_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
//static int dissect_E2SM_RC_QueryOutcome_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
//static int dissect_E2SM_RC_QueryDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
//static int dissect_E2SM_RC_QueryHeader_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);

static int dissect_E2SM_NI_EventTriggerDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_ActionDefinition_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_RANfunction_Description_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_IndicationMessage_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_IndicationHeader_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_CallProcessID_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_ControlHeader_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_ControlMessage_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);
static int dissect_E2SM_NI_ControlOutcome_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_);

enum {
  INITIATING_MESSAGE,
  SUCCESSFUL_OUTCOME,
  UNSUCCESSFUL_OUTCOME
};

typedef struct _e2ap_ctx_t {
  guint32 message_type;
  guint32 ProcedureCode;
  guint32 ProtocolIE_ID;
  guint32 ProtocolExtensionID;
} e2ap_ctx_t;


/* Temporary private info to remember while dissecting frame */
struct e2ap_private_data {
  guint32 procedure_code;
  guint32 protocol_ie_id;
  guint32 protocol_extension_id;
  guint32 message_type;
  guint32 ran_ue_e2ap_id;

  guint32 ran_function_id;
  guint32 gnb_id_len;
#define MAX_GNB_ID_BYTES 6
  guint8  gnb_id_bytes[MAX_GNB_ID_BYTES];
  dissector_handle_t component_configuration_dissector;
};

/* Lookup temporary private info */
static struct e2ap_private_data*
e2ap_get_private_data(packet_info *pinfo)
{
  struct e2ap_private_data *e2ap_data = (struct e2ap_private_data*)p_get_proto_data(pinfo->pool, pinfo, proto_e2ap, 0);
  if (!e2ap_data) {
    e2ap_data = wmem_new0(pinfo->pool, struct e2ap_private_data);
    p_add_proto_data(pinfo->pool, pinfo, proto_e2ap, 0, e2ap_data);
  }
  return e2ap_data;
}

/****************************************************************************************************************/
/* We learn which set of RAN functions pointers corresponds to a given ranFunctionID when we see E2SetupRequest */
/* TODO: unfortunately, it seems that different versions of these protocols are not backward-compatible, so     */
/* it would be good to show where (going by OID) the dissector isn't at the same version as the message..       */
/* An alternative would be to have multiple versions of each protocol and have them register in tables...       */

/* Static table mapping from string -> ran_function */
static const char* g_ran_function_name_table[MAX_RANFUNCTIONS] =
{
    "ORAN-E2SM-KPM",
    "ORAN-E2SM-RC",
    "ORAN-E2SM-NI"
};



/* Per-conversation mapping: ranFunctionId -> ran_function+dissector */
typedef struct {
    guint32                  setup_frame;
    guint32                  ran_function_id;
    ran_function_t           ran_function;
    char                     oid[MAX_OID_LEN];       // i.e., OID from setupRequest
    ran_function_dissector_t *dissector;
} ran_function_id_mapping_t;

typedef struct  {
#define MAX_RANFUNCTION_ENTRIES 8
    guint32                   num_entries;
    ran_function_id_mapping_t entries[MAX_RANFUNCTION_ENTRIES];
} ran_functionid_table_t;

static const char *ran_function_to_str(ran_function_t ran_function)
{
    switch (ran_function) {
        case KPM_RANFUNCTIONS:
            return "KPM";
        case RC_RANFUNCTIONS:
            return "RC";
        case NI_RANFUNCTIONS:
            return "NI";
        default:
            return "Unknown";
    }
}

/* Table of RAN Function tables, indexed by gnbId (bytes) */
typedef struct {
#define MAX_GNBS 6
    guint32 num_gnbs;
    struct {
        guint8  id_value[MAX_GNB_ID_BYTES];
        guint32 id_len;
        ran_functionid_table_t *ran_function_table;
    } gnb[MAX_GNBS];
} gnb_ran_functions_t;

static gnb_ran_functions_t s_gnb_ran_functions_table;


/* Table of available dissectors for each RAN function */
typedef struct {
    guint32                  num_available_dissectors;
#define MAX_DISSECTORS_PER_RAN_FUNCTION 3
    ran_function_dissector_t* ran_function_dissectors[MAX_DISSECTORS_PER_RAN_FUNCTION];
} ran_function_available_dissectors_t;

/* Available dissectors should be set here */
static ran_function_available_dissectors_t g_ran_functions_available_dissectors[MAX_RANFUNCTIONS];

/* Will be called from outside this file by separate dissectors */
void register_e2ap_ran_function_dissector(ran_function_t ran_function, ran_function_dissector_t *dissector)
{
    if ((ran_function >= MIN_RANFUNCTIONS) && (ran_function <= MAX_RANFUNCTIONS)) {
        ran_function_available_dissectors_t *available_dissectors = &g_ran_functions_available_dissectors[ran_function];
        if (available_dissectors->num_available_dissectors < MAX_DISSECTORS_PER_RAN_FUNCTION) {
            available_dissectors->ran_function_dissectors[available_dissectors->num_available_dissectors++] = dissector;
        }
    }
}


/* Get RANfunctionID table from conversation data - create new if necessary */
static ran_functionid_table_t* get_ran_functionid_table(packet_info *pinfo)
{
    conversation_t *p_conv;
    ran_functionid_table_t *p_conv_data = NULL;

    /* Lookup conversation */
    p_conv = find_conversation(pinfo->num, &pinfo->net_dst, &pinfo->net_src,
                               conversation_pt_to_endpoint_type(pinfo->ptype),
                               pinfo->destport, pinfo->srcport, 0);
    if (!p_conv) {
        /* None, so create new data and set */
        p_conv = conversation_new(pinfo->num, &pinfo->net_dst, &pinfo->net_src,
                                  conversation_pt_to_endpoint_type(pinfo->ptype),
                                  pinfo->destport, pinfo->srcport, 0);
        p_conv_data = (ran_functionid_table_t*)wmem_new0(wmem_file_scope(), ran_functionid_table_t);
        conversation_add_proto_data(p_conv, proto_e2ap, p_conv_data);
    }
    else {
        /* Will return existing conversation data */
        p_conv_data = (ran_functionid_table_t*)conversation_get_proto_data(p_conv, proto_e2ap);
    }

    return p_conv_data;
}


/* Store new RANfunctionID -> Service Model mapping in table */
void e2ap_store_ran_function_mapping(packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb, const char *name)
{
    struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);
    ran_functionid_table_t *table = get_ran_functionid_table(pinfo);

    if (!name) {
      return;
    }
    /* Stop if already reached table limit */
    if (table->num_entries == MAX_RANFUNCTION_ENTRIES) {
        proto_tree_add_expert_format(tree, pinfo, &ei_e2ap_ran_function_max_dissectors_registered,
                                     tvb, 0, 0,
                                     "Dissector wants to register for %s, but max (%u) already reached",
                                     name, MAX_RANFUNCTION_ENTRIES);
        return;
    }

    guint32 ran_function_id = e2ap_data->ran_function_id;

    ran_function_t           ran_function = MAX_RANFUNCTIONS;  /* i.e. invalid */
    ran_function_dissector_t *ran_function_dissector = NULL;

    /* Check known RAN function names */
    for (int n=MIN_RANFUNCTIONS; n < MAX_RANFUNCTIONS; n++) {
        if (strcmp(name, g_ran_function_name_table[n]) == 0) {
            ran_function = n;

            /* Don't know OID yet, so for now, just choose first/only one */
            /* TODO: is latest one likely to be more compatible? First fields (at least) come from E2SM.. */
            if (g_ran_functions_available_dissectors[table->entries[n].ran_function].num_available_dissectors) {
                ran_function_dissector = g_ran_functions_available_dissectors[table->entries[n].ran_function].ran_function_dissectors[0];
            }
            break;
        }
    }

    /* Nothing to do if no matches */
    if (ran_function == MAX_RANFUNCTIONS) {
        return;
    }

    /* If ID already mapped, can stop here */
    for (guint n=0; n < table->num_entries; n++) {
        if (table->entries[n].ran_function_id == ran_function_id) {
            return;
        }
    }

    /* OK, store this new entry */
    guint idx = table->num_entries++;
    table->entries[idx].setup_frame = pinfo->num;
    table->entries[idx].ran_function_id = ran_function_id;
    table->entries[idx].ran_function = ran_function;
    table->entries[idx].dissector = ran_function_dissector;

    /* When add first entry, also want to set up table from gnbId -> table */
    if (idx == 0) {
        guint id_len = e2ap_data->gnb_id_len;
        guint8 *id_value = &e2ap_data->gnb_id_bytes[0];

        gboolean found = FALSE;
        for (guint n=0; n<s_gnb_ran_functions_table.num_gnbs; n++) {
            if ((s_gnb_ran_functions_table.gnb[n].id_len = id_len) &&
                (memcmp(s_gnb_ran_functions_table.gnb[n].id_value, id_value, id_len) == 0)) {
                /* Already have an entry for this gnb. */
                found = TRUE;
                break;
            }
        }

        if (!found) {
            /* Add entry (if room for 1 more) */
            guint32 new_idx = s_gnb_ran_functions_table.num_gnbs;
            if (new_idx < MAX_GNBS-1) {
                s_gnb_ran_functions_table.gnb[new_idx].id_len = id_len;
                memcpy(s_gnb_ran_functions_table.gnb[new_idx].id_value, id_value, id_len);
                s_gnb_ran_functions_table.gnb[new_idx].ran_function_table = table;

                s_gnb_ran_functions_table.num_gnbs++;
            }
        }
    }
}

/* Look for Service Model function pointers, based on current RANFunctionID from frame */
static ran_function_dissector_t* lookup_ranfunction_dissector(packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb)
{
    /* Get ranFunctionID from this frame */
    struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);
    guint ran_function_id = e2ap_data->ran_function_id;

    /* Get ranFunction table corresponding to this frame's conversation */
    ran_functionid_table_t *table = get_ran_functionid_table(pinfo);
    if (!table) {
        /* There is no ran function table associated with this frame's conversation info */
        return NULL;
    }

    /* Find the entry in this table corresponding to ran_function_id */
    for (guint n=0; n < table->num_entries; n++) {
        if (ran_function_id == table->entries[n].ran_function_id) {
            if (tree) {
                /* Point back at the setup frame where this ranfunction was mapped */
                proto_item *ti = proto_tree_add_uint(tree, hf_e2ap_ran_function_setup_frame,
                                                     tvb, 0, 0, table->entries[n].setup_frame);
                /* Show that mapping */
                proto_item_append_text(ti, " (%u -> %s)", table->entries[n].ran_function_id, ran_function_to_str(table->entries[n].ran_function));
                proto_item_set_generated(ti);

                /* Also take the chance to compare signalled and available dissector */
                char *frame_version = oid_resolved_from_string(pinfo->pool, table->entries[n].oid);
                ti = proto_tree_add_string(tree, hf_e2ap_frame_version, tvb, 0, 0, frame_version);
                proto_item_set_generated(ti);

                char *dissector_version = oid_resolved_from_string(pinfo->pool, table->entries[n].dissector->oid);
                ti = proto_tree_add_string(tree, hf_e2ap_dissector_version, tvb, 0, 0, dissector_version);
                proto_item_set_generated(ti);

                if (strcmp(frame_version, dissector_version) != 0) {
                    /* Expert info for version mismatch! */
                    expert_add_info_format(pinfo, ti, &ei_e2ap_ran_function_dissector_mismatch,
                                           "Dissector version mismatch - frame is %s but dissector is %s",
                                           frame_version, dissector_version);
                }
            }

            /* Return the dissector */
            return table->entries[n].dissector;
        }
    }

    if (tree) {
        /* No match found.. */
        proto_item *ti = proto_tree_add_item(tree, hf_e2ap_unmapped_ran_function_id, tvb, 0, 0, ENC_NA);
        expert_add_info_format(pinfo, ti, &ei_e2ap_ran_function_id_not_mapped,
                               "Service Model not mapped for FunctionID %u", ran_function_id);
    }

    return NULL;
}

/* Return the oid associated with this frame's conversation */
static char* lookup_ranfunction_oid(packet_info *pinfo)
{
    /* Get ranFunctionID from this frame */
    struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);
    guint ran_function_id = e2ap_data->ran_function_id;

    /* Get ranFunction table corresponding to this frame's conversation */
    ran_functionid_table_t *table = get_ran_functionid_table(pinfo);
    if (!table) {
        /* There is no ran function table associated with this frame's conversation info */
        return NULL;
    }

    /* Find the entry in this table corresponding to ran_function_id */
    for (guint n=0; n < table->num_entries; n++) {
        if (ran_function_id == table->entries[n].ran_function_id) {
            return (char*)(table->entries[n].oid);
        }
    }

    /* Not found */
    return NULL;
}


/* We now know the OID - can we set a dissector that is an exact match from what has been signalled? */
static void update_dissector_using_oid(packet_info *pinfo, ran_function_t ran_function)
{
    char *frame_oid = lookup_ranfunction_oid(pinfo);
    if (frame_oid == NULL) {
        /* TODO: error? */
        return;
    }

    gboolean found = FALSE;

    /* Look at available dissectors for this RAN function */
    ran_function_available_dissectors_t *available = &g_ran_functions_available_dissectors[ran_function];
    if (!available->num_available_dissectors) {
        /* Oops - none available at all! */
        return;
    }

    // Get mapping in use
    struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);
    guint ran_function_id = e2ap_data->ran_function_id;
    ran_function_id_mapping_t *mapping = NULL;
    ran_functionid_table_t *table = get_ran_functionid_table(pinfo);
    /* Find the entry in this table corresponding to ran_function_id */
    for (guint n=0; n < table->num_entries; n++) {
        if (ran_function_id == table->entries[n].ran_function_id) {
            mapping = &(table->entries[n]);
        }
    }

    if (!mapping) {
        return;
    }

    /* Set dissector pointer in ran_function_id_mapping_t */
    for (guint32 n=0; n < available->num_available_dissectors; n++) {
        /* If exact match, set it */
        if (strcmp(frame_oid, available->ran_function_dissectors[n]->oid) == 0) {
            mapping->dissector = available->ran_function_dissectors[n];
            found = TRUE;
            break;
        }
    }

    /* If not exact match, just set to first one available (TODO: closest above better?) */
    if (!found) {
        mapping->dissector = available->ran_function_dissectors[0];
    }
}


/* Update RANfunctionID -> Service Model mapping in table (now that we know OID) */
void e2ap_update_ran_function_mapping(packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb, const char *oid)
{
    /* Copy OID into table entry (so may be used to choose and be compared with chosen available dissector */
    struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);
    ran_functionid_table_t *table = get_ran_functionid_table(pinfo);
    ran_function_t ran_function = MAX_RANFUNCTIONS;
    for (guint n=0; n < table->num_entries; n++) {
        if (e2ap_data->ran_function_id == table->entries[n].ran_function_id) {
            ran_function = table->entries[n].ran_function;
            g_strlcpy(table->entries[n].oid, oid, MAX_OID_LEN);
        }
    }

    /* Look up version from oid and show as generated field */
    char *version = oid_resolved_from_string(pinfo->pool, oid);
    proto_item *ti = proto_tree_add_string(tree, hf_e2ap_frame_version, tvb, 0, 0, version);
    proto_item_set_generated(ti);

    /* Can now pick most appropriate dissector for this RAN Function name, based upon this OID and the available dissectors */
    if (ran_function < MAX_RANFUNCTIONS) {
        if (pinfo->fd->visited) {
            update_dissector_using_oid(pinfo, ran_function);
        }
    }
}

/* This will get used for E2nodeConfigurationUpdate, where we have a gnb-id but haven't seen E2setupRequest */
static void update_conversation_from_gnb_id(asn1_ctx_t *actx)
{
    packet_info *pinfo = actx->pinfo;
    struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

    /* Look for conversation data */
    conversation_t *p_conv;
    ran_functionid_table_t *p_conv_data = NULL;

    /* Lookup conversation */
    p_conv = find_conversation(pinfo->num, &pinfo->net_dst, &pinfo->net_src,
                               conversation_pt_to_endpoint_type(pinfo->ptype),
                               pinfo->destport, pinfo->srcport, 0);

    if (!p_conv) {
        /* None, so create new data and set */
        p_conv = conversation_new(pinfo->num, &pinfo->net_dst, &pinfo->net_src,
                                  conversation_pt_to_endpoint_type(pinfo->ptype),
                                  pinfo->destport, pinfo->srcport, 0);
        p_conv_data = (ran_functionid_table_t*)wmem_new0(wmem_file_scope(), ran_functionid_table_t);
        conversation_add_proto_data(p_conv, proto_e2ap, p_conv_data);

        /* Look to see if we already know about the mappings in effect on this gNB */
        guint id_len = e2ap_data->gnb_id_len;
        guint8 *id_value = &e2ap_data->gnb_id_bytes[0];

        for (guint n=0; n<s_gnb_ran_functions_table.num_gnbs; n++) {
            if ((s_gnb_ran_functions_table.gnb[n].id_len = id_len) &&
                (memcmp(s_gnb_ran_functions_table.gnb[n].id_value, id_value, id_len) == 0)) {

                /* Have an entry for this gnb.  Set direct pointer to existing data (used by original conversation). */
                /* N.B. This means that no further updates for the gNB are expected on different conversations.. */
                p_conv_data = s_gnb_ran_functions_table.gnb[n].ran_function_table;
                conversation_add_proto_data(p_conv, proto_e2ap, p_conv_data);

                /* TODO: may want to try to add a generated field to pass back to E2setupRequest where RAN function mappings were first seen? */
                break;
            }
        }
    }
}


/* Dissector tables */
static dissector_table_t e2ap_ies_dissector_table;

//static dissector_table_t e2ap_ies_p1_dissector_table;
//static dissector_table_t e2ap_ies_p2_dissector_table;
static dissector_table_t e2ap_extension_dissector_table;
static dissector_table_t e2ap_proc_imsg_dissector_table;
static dissector_table_t e2ap_proc_sout_dissector_table;
static dissector_table_t e2ap_proc_uout_dissector_table;
static dissector_table_t e2ap_n2_ie_type_dissector_table;

static int dissect_ProtocolIEFieldValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *);

/* Currently not used
static int dissect_ProtocolIEFieldPairFirstValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
static int dissect_ProtocolIEFieldPairSecondValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
*/


static int dissect_InitiatingMessageValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *);
static int dissect_SuccessfulOutcomeValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *);
static int dissect_UnsuccessfulOutcomeValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *);


#include "packet-e2ap-fn.c"

static int dissect_ProtocolIEFieldValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
  e2ap_ctx_t e2ap_ctx;
  struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

  e2ap_ctx.message_type        = e2ap_data->message_type;
  e2ap_ctx.ProcedureCode       = e2ap_data->procedure_code;
  e2ap_ctx.ProtocolIE_ID       = e2ap_data->protocol_ie_id;
  e2ap_ctx.ProtocolExtensionID = e2ap_data->protocol_extension_id;

  return (dissector_try_uint_new(e2ap_ies_dissector_table, e2ap_data->protocol_ie_id, tvb, pinfo, tree, FALSE, &e2ap_ctx)) ? tvb_captured_length(tvb) : 0;
}



/* Currently not used
static int dissect_ProtocolIEFieldPairFirstValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
  struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

  return (dissector_try_uint(e2ap_ies_p1_dissector_table, e2ap_data->protocol_ie_id, tvb, pinfo, tree)) ? tvb_captured_length(tvb) : 0;
}

static int dissect_ProtocolIEFieldPairSecondValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
  struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

  return (dissector_try_uint(e2ap_ies_p2_dissector_table, e2ap_data->protocol_ie_id, tvb, pinfo, tree)) ? tvb_captured_length(tvb) : 0;
}
*/


static int dissect_InitiatingMessageValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
{
  struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

  return (dissector_try_uint_new(e2ap_proc_imsg_dissector_table, e2ap_data->procedure_code, tvb, pinfo, tree, TRUE, data)) ? tvb_captured_length(tvb) : 0;
}

static int dissect_SuccessfulOutcomeValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
{
  struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

  return (dissector_try_uint_new(e2ap_proc_sout_dissector_table, e2ap_data->procedure_code, tvb, pinfo, tree, TRUE, data)) ? tvb_captured_length(tvb) : 0;
}

static int dissect_UnsuccessfulOutcomeValue(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
{
  struct e2ap_private_data *e2ap_data = e2ap_get_private_data(pinfo);

  return (dissector_try_uint_new(e2ap_proc_uout_dissector_table, e2ap_data->procedure_code, tvb, pinfo, tree, TRUE, data)) ? tvb_captured_length(tvb) : 0;
}


static int
dissect_e2ap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
  proto_item *e2ap_item = NULL;
  proto_tree *e2ap_tree = NULL;

  /* make entry in the Protocol column on summary display */
  col_set_str(pinfo->cinfo, COL_PROTOCOL, "E2AP");
  col_clear(pinfo->cinfo, COL_INFO);

  /* create the e2ap protocol tree */
  e2ap_item = proto_tree_add_item(tree, proto_e2ap, tvb, 0, -1, ENC_NA);
  e2ap_tree = proto_item_add_subtree(e2ap_item, ett_e2ap);

  return dissect_E2AP_PDU_PDU(tvb, pinfo, e2ap_tree, NULL);
}


static void e2ap_init_protocol(void)
{
  s_gnb_ran_functions_table.num_gnbs = 0;
}


/*--- proto_reg_handoff_e2ap ---------------------------------------*/
void
proto_reg_handoff_e2ap(void)
{
  dissector_add_uint_with_preference("sctp.port", SCTP_PORT_E2AP, e2ap_handle);
  dissector_add_uint("sctp.ppi", E2_CP_PROTOCOL_ID, e2ap_handle);
  dissector_add_uint("sctp.ppi", E2_UP_PROTOCOL_ID, e2ap_handle);
  dissector_add_uint("sctp.ppi", E2_DU_PROTOCOL_ID, e2ap_handle);

#include "packet-e2ap-dis-tab.c"

  /********************************/
  /* Known OIDs for RAN providers */

  /* KPM */
  oid_add_from_string("KPM v1",         "1.3.6.1.4.1.53148.1.1.2.2");
  oid_add_from_string("KPM v2",         "1.3.6.1.4.1.53148.1.2.2.2");
  oid_add_from_string("KPM v3",         "1.2.6.1.4.1.53148.1.3.2.2");

  /* RC */
  // TODO: appears to be the same???  Asking for clarification from ORAN..
  oid_add_from_string("RC  v1",         "1.3.6.1.4.1.53148.1.1.2.3");
  //oid_add_from_string("RC  v3",         "1.3.6.1.4.1.53148.1.1.2.3");
  //oid_add_from_string("RC  v4",         "1.3.6.1.4.1.53148.1.1.2.3");

  /* NI */
  oid_add_from_string("NI  v1",         "1.3.6.1.4.1.53148.1.1.2.1");

  /********************************/
  /* Register 'built-in' dissectors */

  static ran_function_dissector_t kpm_v3 =
  { "ORAN-E2SM-KPM", "1.2.6.1.4.1.53148.1.3.2.2", 3, 0,
    {  dissect_E2SM_KPM_RANfunction_Description_PDU,

       NULL,
       NULL,
       NULL,
       NULL,
       NULL,
       NULL,

       dissect_E2SM_KPM_ActionDefinition_PDU,
       dissect_E2SM_KPM_IndicationMessage_PDU,
       dissect_E2SM_KPM_IndicationHeader_PDU,
       NULL, /* no dissect_E2SM_KPM_CallProcessID_PDU */
       dissect_E2SM_KPM_EventTriggerDefinition_PDU
     }
  };

  static ran_function_dissector_t rc_v1 =
  { "ORAN-E2SM-RC",  "1.3.6.1.4.1.53148.1.1.2.3", 1, 3,
    {  dissect_E2SM_RC_RANFunctionDefinition_PDU,

       dissect_E2SM_RC_ControlHeader_PDU,
       dissect_E2SM_RC_ControlMessage_PDU,
       dissect_E2SM_RC_ControlOutcome_PDU,
       /* new for v3 */
       NULL, //dissect_E2SM_RC_QueryOutcome_PDU,
       NULL, //dissect_E2SM_RC_QueryDefinition_PDU,
       NULL, //dissect_E2SM_RC_QueryHeader_PDU,

       dissect_E2SM_RC_ActionDefinition_PDU,
       dissect_E2SM_RC_IndicationMessage_PDU,
       dissect_E2SM_RC_IndicationHeader_PDU,
       dissect_E2SM_RC_CallProcessID_PDU,
       dissect_E2SM_RC_EventTrigger_PDU
    }
  };

  static ran_function_dissector_t ni_v1 =
  { "ORAN-E2SM-NI",  "1.3.6.1.4.1.53148.1.1.2.1", 1, 0,
    {  dissect_E2SM_NI_RANfunction_Description_PDU,

       dissect_E2SM_NI_ControlHeader_PDU,
       dissect_E2SM_NI_ControlMessage_PDU,
       dissect_E2SM_NI_ControlOutcome_PDU,
       NULL,
       NULL,
       NULL,

       dissect_E2SM_NI_ActionDefinition_PDU,
       dissect_E2SM_NI_IndicationMessage_PDU,
       dissect_E2SM_NI_IndicationHeader_PDU,
       dissect_E2SM_NI_CallProcessID_PDU,
       dissect_E2SM_NI_EventTriggerDefinition_PDU
    }
  };

  /* Register available dissectors.  TODO: break these out into separate
   * ASN.1 protocols that register themselves, or leave one of each here? */
  register_e2ap_ran_function_dissector(KPM_RANFUNCTIONS, &kpm_v3);
  register_e2ap_ran_function_dissector(RC_RANFUNCTIONS,  &rc_v1);
  register_e2ap_ran_function_dissector(NI_RANFUNCTIONS,  &ni_v1);
}



/*--- proto_register_e2ap -------------------------------------------*/
void proto_register_e2ap(void) {

  /* List of fields */

  static hf_register_info hf[] = {
#include "packet-e2ap-hfarr.c"
      { &hf_e2ap_unmapped_ran_function_id,
          { "Unmapped RANfunctionID", "e2ap.unmapped-ran-function-id",
            FT_NONE, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},
      { &hf_e2ap_ran_function_name_not_recognised,
          { "RANfunction name not recognised", "e2ap.ran-function-name-not-recognised",
            FT_NONE, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},
      { &hf_e2ap_ran_function_setup_frame,
          { "RANfunction setup frame", "e2ap.setup-frame",
            FT_FRAMENUM, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},

      { &hf_e2ap_dissector_version,
          { "Version (dissector)", "e2ap.version.dissector",
            FT_STRING, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},
      { &hf_e2ap_frame_version,
          { "Version (frame)", "e2ap.version.frame",
            FT_STRING, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},

      { &hf_e2ap_timestamp_string,
          { "Timestamp string", "e2ap.timestamp-string",
            FT_STRING, BASE_NONE, NULL, 0x0,
            NULL, HFILL }},
  };

  /* List of subtrees */
  static gint *ett[] = {
    &ett_e2ap,
#include "packet-e2ap-ettarr.c"
  };

  static ei_register_info ei[] = {
     { &ei_e2ap_ran_function_names_no_match, { "e2ap.ran-function-names-no-match", PI_PROTOCOL, PI_WARN, "RAN Function name doesn't match known service models", EXPFILL }},
     { &ei_e2ap_ran_function_id_not_mapped,   { "e2ap.ran-function-id-not-known", PI_PROTOCOL, PI_WARN, "Service Model not known for RANFunctionID", EXPFILL }},
     { &ei_e2ap_ran_function_dissector_mismatch,   { "e2ap.ran-function-dissector-version-mismatch", PI_PROTOCOL, PI_WARN, "Available dissector does not match signalled", EXPFILL }},
     { &ei_e2ap_ran_function_max_dissectors_registered,   { "e2ap.ran-function-max-dissectors-registered", PI_PROTOCOL, PI_WARN, "Available dissector does not match signalled", EXPFILL }},

  };

  expert_module_t* expert_e2ap;

  /* Register protocol */
  proto_e2ap = proto_register_protocol(PNAME, PSNAME, PFNAME);
  /* Register fields and subtrees */
  proto_register_field_array(proto_e2ap, hf, array_length(hf));
  proto_register_subtree_array(ett, array_length(ett));


  /* Register dissector */
  e2ap_handle = register_dissector("e2ap", dissect_e2ap, proto_e2ap);

  expert_e2ap = expert_register_protocol(proto_e2ap);
  expert_register_field_array(expert_e2ap, ei, array_length(ei));

  /* Register dissector tables */
  e2ap_ies_dissector_table = register_dissector_table("e2ap.ies", "E2AP-PROTOCOL-IES", proto_e2ap, FT_UINT32, BASE_DEC);

  //  e2ap_ies_p1_dissector_table = register_dissector_table("e2ap.ies.pair.first", "E2AP-PROTOCOL-IES-PAIR FirstValue", proto_e2ap, FT_UINT32, BASE_DEC);
  //  e2ap_ies_p2_dissector_table = register_dissector_table("e2ap.ies.pair.second", "E2AP-PROTOCOL-IES-PAIR SecondValue", proto_e2ap, FT_UINT32, BASE_DEC);
  e2ap_extension_dissector_table = register_dissector_table("e2ap.extension", "E2AP-PROTOCOL-EXTENSION", proto_e2ap, FT_UINT32, BASE_DEC);
  e2ap_proc_imsg_dissector_table = register_dissector_table("e2ap.proc.imsg", "E2AP-ELEMENTARY-PROCEDURE InitiatingMessage", proto_e2ap, FT_UINT32, BASE_DEC);
  e2ap_proc_sout_dissector_table = register_dissector_table("e2ap.proc.sout", "E2AP-ELEMENTARY-PROCEDURE SuccessfulOutcome", proto_e2ap, FT_UINT32, BASE_DEC);
  e2ap_proc_uout_dissector_table = register_dissector_table("e2ap.proc.uout", "E2AP-ELEMENTARY-PROCEDURE UnsuccessfulOutcome", proto_e2ap, FT_UINT32, BASE_DEC);
  e2ap_n2_ie_type_dissector_table = register_dissector_table("e2ap.n2_ie_type", "E2AP N2 IE Type", proto_e2ap, FT_STRING, STRING_CASE_SENSITIVE);

  register_init_routine(&e2ap_init_protocol);
}

/*
 * Editor modelines
 *
 * Local Variables:
 * c-basic-offset: 2
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 *
 * ex: set shiftwidth=2 tabstop=8 expandtab:
 * :indentSize=2:tabSize=8:noTabs=true:
 */