/src/wireshark/epan/expert.c

Source
/* expert.c
 * Collecting Expert information.
 *
 * Implemented as a tap named "expert".
 *
 * 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"
#define WS_LOG_DOMAIN LOG_DOMAIN_EPAN

#include <stdio.h>

#include <epan/packet.h>
#include "expert.h"
#include "uat.h"
#include "prefs.h"
#include <epan/prefs-int.h>
#include <epan/wmem_scopes.h>
#include "tap.h"

#include <wsutil/str_util.h>
#include <wsutil/wslog.h>
#include <wsutil/array.h>

/* proto_expert cannot be static because it's referenced in the
 * print routines
 */
int proto_expert;

static int proto_malformed;

static int expert_tap;
static int highest_severity;

static int ett_expert;
static int ett_subexpert;

static int hf_expert_msg;
static int hf_expert_group;
static int hf_expert_severity;

struct expert_module
{
  const char *proto_name;
  int         proto_id;      /* Cache this for registering hfs */
};

/* List which stores protocols and expert_info that have been registered */
typedef struct _gpa_expertinfo_t {
  uint32_t            len;
  uint32_t            allocated_len;
  expert_field_info **ei;
} gpa_expertinfo_t;
static gpa_expertinfo_t gpa_expertinfo;

/* Hash table of abbreviations and IDs */
static GHashTable *gpa_name_map;
static expert_field_info *same_name_expinfo;

static void save_same_name_expinfo(void *data)
{
  same_name_expinfo = (expert_field_info*)data;
}

/* Deregistered expert infos */
static GPtrArray *deregistered_expertinfos;

const value_string expert_group_vals[] = {
  { PI_CHECKSUM,          "Checksum" },
  { PI_SEQUENCE,          "Sequence" },
  { PI_RESPONSE_CODE,     "Response" },
  { PI_REQUEST_CODE,      "Request" },
  { PI_UNDECODED,         "Undecoded" },
  { PI_REASSEMBLE,        "Reassemble" },
  { PI_MALFORMED,         "Malformed" },
  { PI_DEBUG,             "Debug" },
  { PI_PROTOCOL,          "Protocol" },
  { PI_SECURITY,          "Security" },
  { PI_COMMENTS_GROUP,    "Comment" },
  { PI_DECRYPTION,        "Decryption" },
  { PI_ASSUMPTION,        "Assumption" },
  { PI_DEPRECATED,        "Deprecated" },
  { PI_RECEIVE,           "Receive" },
  { PI_INTERFACE,         "Interface" },
  { PI_DISSECTOR_BUG,     "Dissector bug" },
  { 0, NULL }
};

const value_string expert_severity_vals[] = {
  { PI_ERROR,             "Error" },
  { PI_WARN,              "Warning" },
  { PI_NOTE,              "Note" },
  { PI_CHAT,              "Chat" },
  { PI_COMMENT,           "Comment" },
  { 0, NULL }
};

/* Possible values for a checksum evaluation */
const value_string expert_checksum_vals[] = {
  { EXPERT_CHECKSUM_DISABLED,   "Disabled"  },
  { EXPERT_CHECKSUM_UNKNOWN,    "Unknown"  },
  { EXPERT_CHECKSUM_GOOD,       "Good"  },
  { EXPERT_CHECKSUM_BAD,        "Bad" },
  { 0,        NULL }
};

static expert_field_info *expert_registrar_get_byname(const char *field_name);

/*----------------------------------------------------------------------------*/
/* UAT for customizing severity levels.                                       */
/*----------------------------------------------------------------------------*/
typedef struct
{
  char    *field;
  uint32_t severity;
} expert_level_entry_t;

static expert_level_entry_t *uat_expert_entries;
static unsigned expert_level_entry_count;
/* Array of field names currently in UAT */
static GArray *uat_saved_fields;

UAT_CSTRING_CB_DEF(uat_expert_entries, field, expert_level_entry_t)
UAT_VS_DEF(uat_expert_entries, severity, expert_level_entry_t, uint32_t, PI_ERROR, "Error")

static bool uat_expert_update_cb(void *r, char **err)
{
  expert_level_entry_t *rec = (expert_level_entry_t *)r;

  if (expert_registrar_get_byname(rec->field) == NULL) {
    *err = ws_strdup_printf("Expert Info field doesn't exist: %s", rec->field);
    return false;
  }
  return true;
}

static void *uat_expert_copy_cb(void *n, const void *o, size_t siz _U_)
{
  expert_level_entry_t       *new_record = (expert_level_entry_t*)n;
  const expert_level_entry_t *old_record = (const expert_level_entry_t *)o;

  new_record->field = g_strdup(old_record->field);

  new_record->severity = old_record->severity;

  return new_record;
}

static void uat_expert_free_cb(void*r)
{
  expert_level_entry_t *rec = (expert_level_entry_t *)r;

  g_free(rec->field);
}

static void uat_expert_post_update_cb(void)
{
  unsigned           i;
  expert_field_info *field;

  /* Reset any of the previous list of expert info fields to their original severity */
  for ( i = 0 ; i < uat_saved_fields->len; i++ ) {
    field = g_array_index(uat_saved_fields, expert_field_info*, i);
    if (field != NULL) {
      field->severity = field->orig_severity;
    }
  }

  g_array_set_size(uat_saved_fields, 0);

  for (i = 0; i < expert_level_entry_count; i++)
  {
    field = expert_registrar_get_byname(uat_expert_entries[i].field);
    if (field != NULL)
    {
      field->severity = uat_expert_entries[i].severity;
      g_array_append_val(uat_saved_fields, field);
    }
  }
}

#define EXPERT_REGISTRAR_GET_NTH(eiindex, expinfo)                                               \
  if((unsigned)eiindex >= gpa_expertinfo.len && wireshark_abort_on_dissector_bug)   \
    ws_error("Unregistered expert info! index=%d", eiindex);                          \
  DISSECTOR_ASSERT_HINT((unsigned)eiindex < gpa_expertinfo.len, "Unregistered expert info!"); \
  DISSECTOR_ASSERT_HINT(gpa_expertinfo.ei[eiindex] != NULL, "Unregistered expert info!");  \
  expinfo = gpa_expertinfo.ei[eiindex];

void
expert_packet_init(void)
{
  module_t *module_expert;
  uat_t    *expert_uat;

  static hf_register_info hf[] = {
    { &hf_expert_msg,
      { "Message", "_ws.expert.message", FT_STRING, BASE_NONE, NULL, 0, "Wireshark expert information", HFILL }
    },
    { &hf_expert_group,
      { "Group", "_ws.expert.group", FT_UINT32, BASE_NONE, VALS(expert_group_vals), 0, "Wireshark expert group", HFILL }
    },
    { &hf_expert_severity,
      { "Severity level", "_ws.expert.severity", FT_UINT32, BASE_NONE, VALS(expert_severity_vals), 0, "Wireshark expert severity level", HFILL }
    }
  };
  static int *ett[] = {
    &ett_expert,
    &ett_subexpert
  };

  /* UAT for overriding severity levels */
  static uat_field_t custom_expert_fields[] = {
    UAT_FLD_CSTRING(uat_expert_entries, field, "Field name", "Expert Info filter name"),
    UAT_FLD_VS(uat_expert_entries, severity, "Severity", expert_severity_vals, "Custom severity level"),
    UAT_END_FIELDS
  };

  if (expert_tap == 0) {
    expert_tap = register_tap("expert");
  }

  if (proto_expert <= 0) {
    proto_expert = proto_register_protocol("Expert Info", "Expert", "_ws.expert");
    proto_register_field_array(proto_expert, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));
    proto_set_cant_toggle(proto_expert);

    module_expert = prefs_register_protocol(proto_expert, NULL);
    //Since "expert" is really a pseudo protocol, it shouldn't be
    //categorized with other "real" protocols when it comes to
    //preferences.  Since it's just a UAT, don't bury it in
    //with the other protocols
    module_expert->use_gui = false;

    expert_uat = uat_new("Expert Info Severity Level Configuration",
      sizeof(expert_level_entry_t),
      "expert_severity",
      true,
      (void **)&uat_expert_entries,
      &expert_level_entry_count,
      UAT_AFFECTS_DISSECTION,
      NULL,
      uat_expert_copy_cb,
      uat_expert_update_cb,
      uat_expert_free_cb,
      uat_expert_post_update_cb,
      NULL,
      custom_expert_fields);

    prefs_register_uat_preference(module_expert,
      "expert_severity_levels",
      "Severity Level Configuration",
      "A table that overrides Expert Info field severity levels to user configured levels",
      expert_uat);

  }

  highest_severity = 0;

  proto_malformed = proto_get_id_by_filter_name("_ws.malformed");
}

void
expert_init(void)
{
  gpa_expertinfo.len           = 0;
  gpa_expertinfo.allocated_len = 0;
  gpa_expertinfo.ei            = NULL;
  gpa_name_map                 = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, save_same_name_expinfo);
  uat_saved_fields             = g_array_new(false, false, sizeof(expert_field_info*));
  deregistered_expertinfos     = g_ptr_array_new();
}

void
expert_packet_cleanup(void)
{
}

void
expert_cleanup(void)
{
  if (gpa_expertinfo.allocated_len) {
    gpa_expertinfo.len           = 0;
    gpa_expertinfo.allocated_len = 0;
    g_free(gpa_expertinfo.ei);
    gpa_expertinfo.ei          = NULL;
  }

  /* Free the abbrev/ID GTree */
  if (gpa_name_map) {
    g_hash_table_destroy(gpa_name_map);
    gpa_name_map = NULL;
  }

  /* Free the UAT saved fields */
  if (uat_saved_fields) {
    g_array_free(uat_saved_fields, true);
    uat_saved_fields = NULL;
  }

  if (deregistered_expertinfos) {
    g_ptr_array_free(deregistered_expertinfos, true);
    deregistered_expertinfos = NULL;
  }
}


int
expert_get_highest_severity(void)
{
  return highest_severity;
}

void
expert_update_comment_count(uint64_t count)
{
  if (count==0 && highest_severity==PI_COMMENT)
    highest_severity = 0;
}

//coverity[-alloc]
expert_module_t *expert_register_protocol(int id)
{
  expert_module_t *module;
  protocol_t      *protocol;

  protocol = find_protocol_by_id(id);

  module = wmem_new(wmem_epan_scope(), expert_module_t);
  module->proto_id = id;
  module->proto_name = proto_get_protocol_short_name(protocol);

  return module;
}

void
expert_deregister_expertinfo (const char *abbrev)
{
  expert_field_info *expinfo = (expert_field_info*)g_hash_table_lookup(gpa_name_map, abbrev);
  while (expinfo) {
    g_ptr_array_add(deregistered_expertinfos, gpa_expertinfo.ei[expinfo->id]);
    g_hash_table_steal(gpa_name_map, abbrev);
    expinfo->hf_info.hfinfo.blurb = NULL;
    expinfo = expinfo->same_name_next;
  }
}

void
expert_deregister_protocol (expert_module_t *module)
{
  wmem_free(wmem_epan_scope(), module);
}

static void
free_deregistered_expertinfo (void *data, void *user_data _U_)
{
  expert_field_info *expinfo = (expert_field_info *) data;
  gpa_expertinfo.ei[expinfo->id] = NULL; /* Invalidate this id */
}

void
expert_free_deregistered_expertinfos (void)
{
  g_ptr_array_foreach(deregistered_expertinfos, free_deregistered_expertinfo, NULL);
  g_ptr_array_free(deregistered_expertinfos, true);
  deregistered_expertinfos = g_ptr_array_new();
}

static int
expert_register_field_init(expert_field_info *expinfo, expert_module_t *module)
{
  /* Check for valid group and severity vals */
  switch (expinfo->group) {
    case PI_CHECKSUM:
    case PI_SEQUENCE:
    case PI_RESPONSE_CODE:
    case PI_REQUEST_CODE:
    case PI_UNDECODED:
    case PI_REASSEMBLE:
    case PI_MALFORMED:
    case PI_DEBUG:
    case PI_PROTOCOL:
    case PI_SECURITY:
    case PI_COMMENTS_GROUP:
    case PI_DECRYPTION:
    case PI_ASSUMPTION:
    case PI_DEPRECATED:
    case PI_RECEIVE:
    case PI_INTERFACE:
    case PI_DISSECTOR_BUG:
      break;
    default:
      REPORT_DISSECTOR_BUG("Expert info for %s has invalid group=0x%08x\n", expinfo->name, expinfo->group);
  }
  switch (expinfo->severity) {
    case PI_COMMENT:
    case PI_CHAT:
    case PI_NOTE:
    case PI_WARN:
    case PI_ERROR:
      break;
    default:
      REPORT_DISSECTOR_BUG("Expert info for %s has invalid severity=0x%08x\n", expinfo->name, expinfo->severity);
  }

  expinfo->protocol      = module->proto_name;

  /* if we always add and never delete, then id == len - 1 is correct */
  if (gpa_expertinfo.len >= gpa_expertinfo.allocated_len) {
    if (!gpa_expertinfo.ei) {
      gpa_expertinfo.allocated_len = PRE_ALLOC_EXPERT_FIELDS_MEM;
      gpa_expertinfo.ei = (expert_field_info **)g_malloc(sizeof(expert_field_info *)*PRE_ALLOC_EXPERT_FIELDS_MEM);
    } else {
      gpa_expertinfo.allocated_len += 1000;
      gpa_expertinfo.ei = (expert_field_info **)g_realloc(gpa_expertinfo.ei,
               sizeof(expert_field_info *)*gpa_expertinfo.allocated_len);
    }
  }
  gpa_expertinfo.ei[gpa_expertinfo.len] = expinfo;
  gpa_expertinfo.len++;
  expinfo->id = gpa_expertinfo.len - 1;
  /* Save the original severity so it can be restored by the UAT */
  expinfo->orig_severity = expinfo->severity;

  /* save field name for lookup */
  same_name_expinfo = NULL;
  g_hash_table_replace(gpa_name_map, (void *)expinfo->name, expinfo);
  if (same_name_expinfo) {
    expinfo->same_name_next = same_name_expinfo;
  }

  return expinfo->id;
}


/* for use with static arrays only, since we don't allocate our own copies
of the expert_field_info struct contained within the exp_register_info struct */
void
expert_register_field_array(expert_module_t *module, ei_register_info *exp, const int num_records)
{
  int     i;
  ei_register_info *ptr = exp;

  for (i = 0; i < num_records; i++, ptr++) {
    /*
     * Make sure we haven't registered this yet.
     * Most fields have variables associated with them
     * that are initialized to -1; some have array elements,
     * or possibly uninitialized variables, so we also allow
     * 0 (which is unlikely to be the field ID we get back
     * from "expert_register_field_init()").
     */
    if (ptr->ids->ei != -1 && ptr->ids->ei != 0) {
      fprintf(stderr,
        "Duplicate field detected in call to expert_register_field_array: '%s' is already registered, name=%s\n",
        ptr->eiinfo.summary, ptr->eiinfo.name);
      return;
    }

    /* Register the field with the experts */
    ptr->ids->ei = expert_register_field_init(&ptr->eiinfo, module);

    /* Register with the header field info, so it's display filterable */
    ptr->eiinfo.hf_info.p_id = &ptr->ids->hf;
    ptr->eiinfo.hf_info.hfinfo.name = ptr->eiinfo.summary;
    ptr->eiinfo.hf_info.hfinfo.abbrev = ptr->eiinfo.name;
    ptr->eiinfo.hf_info.hfinfo.blurb = "Expert_Item";

    proto_register_field_array(module->proto_id, &ptr->eiinfo.hf_info, 1);
  }
}

/* Finds a record in the expert array by name.
 * For the moment, this function is only used "internally"
 * but may find a reason to be exported
 */
static expert_field_info *
expert_registrar_get_byname(const char *field_name)
{
  expert_field_info *hfinfo;

  if (!field_name)
    return NULL;

  hfinfo = (expert_field_info*)g_hash_table_lookup(gpa_name_map, field_name);

  return hfinfo;
}

/**
 * Get summary text of an expert_info field.
 * This is intended for use in expert_add_info_format or proto_tree_add_expert_format
 * to get the "base" string to then append additional information
 */
const char* expert_get_summary(expert_field *eiindex)
{
  expert_field_info *eiinfo;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(eiindex->ei, eiinfo);

  return eiinfo->summary;
}

/** clear flags according to the mask and set new flag values */
#define FI_REPLACE_FLAGS(fi, mask, flags_in) { \
  (fi->flags = (fi)->flags & ~(mask)); \
  (fi->flags = (fi)->flags | (flags_in)); \
}

/* set's the PI_ flags to a protocol item
 * (and its parent items till the toplevel) */
static void
// NOLINTNEXTLINE(misc-no-recursion)
expert_set_item_flags(proto_item *pi, const int group, const unsigned severity)
{
  if (pi != NULL && PITEM_FINFO(pi) != NULL && (severity >= FI_GET_FLAG(PITEM_FINFO(pi), PI_SEVERITY_MASK))) {
    FI_REPLACE_FLAGS(PITEM_FINFO(pi), PI_GROUP_MASK, group);
    FI_REPLACE_FLAGS(PITEM_FINFO(pi), PI_SEVERITY_MASK, severity);

    /* propagate till toplevel item */
    pi = proto_item_get_parent(pi);
    // We recurse here, but we're limited by our tree depth checks in proto.c
    expert_set_item_flags(pi, group, severity);
  }
}

static proto_tree*
expert_create_tree(proto_item *pi, packet_info* pinfo, int group, int severity, const char *msg)
{
  proto_tree *tree;
  proto_item *ti;

  tree = proto_item_add_subtree(pi, ett_expert);
  ti = proto_tree_add_protocol_format(tree, proto_expert, NULL, 0, 0, "Expert Info (%s/%s): %s",
              val_to_str(pinfo->pool, severity, expert_severity_vals, "Unknown (%u)"),
              val_to_str(pinfo->pool, group, expert_group_vals, "Unknown (%u)"),
              msg);
  proto_item_set_generated(ti);

  if (group == PI_MALFORMED) {
    /* Add hidden malformed protocol filter */
    proto_item *malformed_ti = proto_tree_add_item(tree, proto_malformed, NULL, 0, 0, ENC_NA);
    proto_item_set_hidden(malformed_ti);
  }

  return proto_item_add_subtree(ti, ett_subexpert);
}

static proto_tree*
expert_set_info_vformat(packet_info *pinfo, proto_item *pi, int group, int severity, int hf_index, bool use_vaformat,
      const char *format, va_list ap)
{
  char           formatted[ITEM_LABEL_LENGTH];
  int            pos;
  int            tap;
  expert_info_t *ei;
  proto_tree    *tree;
  proto_item    *ti;

  if (pinfo == NULL && pi && pi->tree_data) {
    pinfo = PTREE_DATA(pi)->pinfo;
  }

  /* if this packet isn't loaded because of a read filter, don't output anything */
  if (pinfo == NULL || pinfo->num == 0) {
    return NULL;
  }

  /* severity - the severity of this item
   * highest_severity - the highest severity in the entire capture,
   *  used to set the color/tooltip in the main status bar
   * pinfo->expert_severity - the highest severity of an item in the
   *  entire frame, used for setting COL_EXPERT. We always have
   *  packet_info at this point.
   * FI_GET_FLAG(PITEM_FINFO(pi)) - the highest severity of an item
   *  or its descendants, used to set the background color in
   *  proto_tree_model.cpp. Note we can't set or get this if an item
   *  is faked.
   */
  if (severity > highest_severity) {
    highest_severity = severity;
  }

  /* The item might be faked, but we still need to tap it even so, e.g.,
   * for the Expert Info dialog or CLI tap. */
  if (pi != NULL && PITEM_FINFO(pi) != NULL) {
    expert_set_item_flags(pi, group, severity);
  }

  if ((unsigned)severity > pinfo->expert_severity) {
    pinfo->expert_severity = (unsigned)severity;
    col_add_str(pinfo->cinfo, COL_EXPERT, val_to_str(pinfo->pool, severity, expert_severity_vals, "Unknown (%u)"));
  }

  if (use_vaformat) {
    pos = vsnprintf(formatted, ITEM_LABEL_LENGTH, format, ap);
  } else {
    pos = (int)g_strlcpy(formatted, format, ITEM_LABEL_LENGTH);
  }

  /* Both vsnprintf and g_strlcpy return the number of bytes attempted
         * to write.
         */
        if (pos >= ITEM_LABEL_LENGTH) {
    /* Truncation occurred. It might have split a UTF-8 character. */
    ws_utf8_truncate(formatted, ITEM_LABEL_LENGTH - 1);
  }

  tree = expert_create_tree(pi, pinfo, group, severity, formatted);

  if (hf_index <= 0) {
    /* If no filterable expert info, just add the message */
    ti = proto_tree_add_string(tree, hf_expert_msg, NULL, 0, 0, formatted);
    proto_item_set_generated(ti);
  } else {
    /* If filterable expert info, hide the "generic" form of the message,
       and generate the formatted filterable expert info */
    ti = proto_tree_add_none_format(tree, hf_index, NULL, 0, 0, "%s", formatted);
    proto_item_set_generated(ti);
    ti = proto_tree_add_string(tree, hf_expert_msg, NULL, 0, 0, formatted);
    proto_item_set_hidden(ti);
  }

  ti = proto_tree_add_uint_format_value(tree, hf_expert_severity, NULL, 0, 0, severity,
                "%s", val_to_str_const(severity, expert_severity_vals, "Unknown"));
  proto_item_set_generated(ti);
  ti = proto_tree_add_uint_format_value(tree, hf_expert_group, NULL, 0, 0, group,
                "%s", val_to_str_const(group, expert_group_vals, "Unknown"));
  proto_item_set_generated(ti);

  tap = have_tap_listener(expert_tap);

  if (!tap)
    return tree;

  ei = wmem_new(pinfo->pool, expert_info_t);

  ei->packet_num  = pinfo->num;
  ei->group       = group;
  ei->severity    = severity;
  ei->hf_index    = hf_index;
  ei->protocol    = pinfo->current_proto;
  ei->summary     = wmem_strdup(pinfo->pool, formatted);

  /* if we have a proto_item (not a faked item), set expert attributes to it */
  if (pi != NULL && PITEM_FINFO(pi) != NULL) {
    ei->pitem = pi;
  }
  else {
    ei->pitem = NULL;
  }

  tap_queue_packet(expert_tap, pinfo, ei);
  return tree;
}

/* Helper function for expert_add_info() to work around compiler's special needs on ARM */
static inline proto_tree*
expert_add_info_internal(packet_info *pinfo, proto_item *pi, expert_field *expindex, ...)
{
  /* the va_list is ignored */
  va_list            unused;
  expert_field_info *eiinfo;
  proto_tree        *tree;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(expindex->ei, eiinfo);

  va_start(unused, expindex);
  tree = expert_set_info_vformat(pinfo, pi, eiinfo->group, eiinfo->severity, *eiinfo->hf_info.p_id, false, eiinfo->summary, unused);
  va_end(unused);
  return tree;
}

proto_item *
expert_add_info(packet_info *pinfo, proto_item *pi, expert_field *expindex)
{
  proto_tree        *tree;
  tree = expert_add_info_internal(pinfo, pi, expindex);
  return (proto_item *)tree;
}

proto_item *
expert_add_info_format(packet_info *pinfo, proto_item *pi, expert_field *expindex, const char *format, ...)
{
  va_list            ap;
  expert_field_info *eiinfo;
  proto_tree        *tree;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(expindex->ei, eiinfo);

  va_start(ap, format);
  tree = expert_set_info_vformat(pinfo, pi, eiinfo->group, eiinfo->severity, *eiinfo->hf_info.p_id, true, format, ap);
  va_end(ap);
  return (proto_item *)tree;
}

/* Helper function for expert_add_expert() to work around compiler's special needs on ARM */
static inline proto_item *
proto_tree_add_expert_internal(proto_tree *tree, packet_info *pinfo, expert_field *expindex,
    tvbuff_t *tvb, unsigned start, unsigned length, ...)
{
  expert_field_info *eiinfo;
  proto_item        *ti;
  unsigned           item_length, captured_length;
  va_list            unused;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(expindex->ei, eiinfo);

  /* Make sure this doesn't throw an exception when adding the item */
  item_length = length;
  captured_length = tvb_captured_length_remaining(tvb, start);
  if (captured_length < item_length) {
    item_length = captured_length;
  }
  ti = proto_tree_add_text_internal(tree, tvb, start, item_length, "%s", eiinfo->summary);
  va_start(unused, length);
  expert_set_info_vformat(pinfo, ti, eiinfo->group, eiinfo->severity, *eiinfo->hf_info.p_id, false, eiinfo->summary, unused);
  va_end(unused);

  /* But make sure it throws an exception *after* adding the item */
  tvb_ensure_bytes_exist(tvb, start, length);

  return ti;
}

static inline proto_item*
proto_tree_add_expert_internal_remaining(proto_tree* tree, packet_info* pinfo, expert_field* expindex,
  tvbuff_t* tvb, unsigned start, ...)
{
  expert_field_info* eiinfo;
  proto_item*        ti;
  unsigned           item_length, captured_length;
  va_list            unused;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(expindex->ei, eiinfo);

  /* Make sure this doesn't throw an exception when adding the item */
  captured_length = tvb_captured_length(tvb);
  if (start >= captured_length) {
    item_length = 0;
  } else {
    item_length = captured_length - start;
  }
  ti = proto_tree_add_text_internal(tree, tvb, start, item_length, "%s", eiinfo->summary);
  va_start(unused, start);
  expert_set_info_vformat(pinfo, ti, eiinfo->group, eiinfo->severity, *eiinfo->hf_info.p_id, false, eiinfo->summary, unused);
  va_end(unused);

  return ti;
}
proto_item *
proto_tree_add_expert(proto_tree *tree, packet_info *pinfo, expert_field *expindex,
    tvbuff_t *tvb, unsigned start, unsigned length)
{
  return proto_tree_add_expert_internal(tree, pinfo, expindex, tvb, start, length);
}

proto_item*
proto_tree_add_expert_remaining(proto_tree* tree, packet_info* pinfo, expert_field* expindex,
  tvbuff_t* tvb, unsigned start)
{
  return proto_tree_add_expert_internal_remaining(tree, pinfo, expindex, tvb, start);
}

proto_item *
proto_tree_add_expert_format(proto_tree *tree, packet_info *pinfo, expert_field *expindex,
    tvbuff_t *tvb, unsigned start, unsigned length, const char *format, ...)
{
  va_list            ap;
  expert_field_info *eiinfo;
  unsigned           item_length, captured_length;
  proto_item        *ti;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(expindex->ei, eiinfo);

  /* Make sure this doesn't throw an exception when adding the item */
  item_length = length;
  captured_length = tvb_captured_length_remaining(tvb, start);
  if (captured_length < item_length) {
    item_length = captured_length;
  }
  va_start(ap, format);
  ti = proto_tree_add_text_valist_internal(tree, tvb, start, item_length, format, ap);
  va_end(ap);

  va_start(ap, format);
  expert_set_info_vformat(pinfo, ti, eiinfo->group, eiinfo->severity, *eiinfo->hf_info.p_id, true, format, ap);
  va_end(ap);

  /* But make sure it throws an exception *after* adding the item */
  tvb_ensure_bytes_exist(tvb, start, length);

  return ti;
}

proto_item*
proto_tree_add_expert_format_remaining(proto_tree* tree, packet_info* pinfo, expert_field* expindex,
  tvbuff_t* tvb, unsigned start, const char* format, ...)
{
  va_list            ap;
  expert_field_info* eiinfo;
  unsigned           item_length, captured_length;
  proto_item* ti;

  /* Look up the item */
  EXPERT_REGISTRAR_GET_NTH(expindex->ei, eiinfo);

  /* Make sure this doesn't throw an exception when adding the item */
  captured_length = tvb_captured_length(tvb);
  if (start >= captured_length) {
    item_length = 0;
  } else {
    item_length = captured_length - start;
  }
  va_start(ap, format);
  ti = proto_tree_add_text_valist_internal(tree, tvb, start, item_length, format, ap);
  va_end(ap);

  va_start(ap, format);
  expert_set_info_vformat(pinfo, ti, eiinfo->group, eiinfo->severity, *eiinfo->hf_info.p_id, true, format, ap);
  va_end(ap);

  return ti;
}
/*
 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 *
 * Local variables:
 * c-basic-offset: 8
 * tab-width: 8
 * indent-tabs-mode: t
 * End:
 *
 * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 * :indentSize=8:tabSize=8:noTabs=false:
 */

Coverage Report

Created: 2026-03-30 07:00