/* disabled_protos.c
 * Code for reading and writing the disabled protocols file.
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"

#include <stdio.h>
#include <string.h>
#include <errno.h>

#include <glib.h>

#include <wsutil/filesystem.h>
#include <epan/proto.h>
#include <epan/packet.h>

#include "disabled_protos.h"
#include <wsutil/file_util.h>

#define PROTOCOLS_FILE_NAME             "disabled_protos"
#define HEURISTICS_FILE_NAME            "heuristic_protos"

/*
 * Item in a list of disabled protocols.
 */
typedef struct {
  char *name;		/* protocol name */
} protocol_def;

/*
 * Item in a list of heuristic dissectors and their enabled state.
 */
typedef struct {
  char *name;		/* heuristic short name */
  gboolean enabled;	/* heuristc enabled */
} heur_protocol_def;

/*
 * List of disabled protocols
 */
static GList *global_disabled_protos = NULL;
static GList *disabled_protos = NULL;
/*
 * List of disabled heuristics
 */
static GList *global_disabled_heuristics = NULL;
static GList *disabled_heuristics = NULL;

#define INIT_BUF_SIZE   128

static void
discard_existing_list (GList **flp)
{
  GList      *fl_ent;
  protocol_def *prot;

  if (*flp != NULL) {
    fl_ent = g_list_first(*flp);
    while (fl_ent != NULL) {
      prot = (protocol_def *) fl_ent->data;
      g_free(prot->name);
      g_free(prot);
      fl_ent = fl_ent->next;
    }
    g_list_free(*flp);
    *flp = NULL;
  }
}

static void
heur_discard_existing_list (GList **flp)
{
  GList      *fl_ent;
  heur_protocol_def *prot;

  if (*flp != NULL) {
    fl_ent = g_list_first(*flp);
    while (fl_ent != NULL) {
      prot = (heur_protocol_def *) fl_ent->data;
      g_free(prot->name);
      g_free(prot);
      fl_ent = fl_ent->next;
    }
    g_list_free(*flp);
    *flp = NULL;
  }
}

/*
 * Read in a list of disabled protocols.
 *
 * On success, "*pref_path_return" is set to NULL.
 * On error, "*pref_path_return" is set to point to the pathname of
 * the file we tried to read - it should be freed by our caller -
 * and "*open_errno_return" is set to the error if an open failed
 * or "*read_errno_return" is set to the error if a read failed.
 */

static int read_disabled_protos_list_file(const char *ff_path, FILE *ff,
                                          GList **flp);

void
read_disabled_protos_list(char **gpath_return, int *gopen_errno_return,
                          int *gread_errno_return,
                          char **path_return, int *open_errno_return,
                          int *read_errno_return)
{
  int         err;
  char       *gff_path, *ff_path;
  FILE       *ff;

  /* Construct the pathname of the global disabled protocols file. */
  gff_path = get_datafile_path(PROTOCOLS_FILE_NAME);

  /* If we already have a list of protocols, discard it. */
  discard_existing_list (&global_disabled_protos);

  /* Read the global disabled protocols file, if it exists. */
  *gpath_return = NULL;
  if ((ff = ws_fopen(gff_path, "r")) != NULL) {
    /* We succeeded in opening it; read it. */
    err = read_disabled_protos_list_file(gff_path, ff,
                                         &global_disabled_protos);
    if (err != 0) {
      /* We had an error reading the file; return the errno and the
         pathname, so our caller can report the error. */
      *gopen_errno_return = 0;
      *gread_errno_return = err;
      *gpath_return = gff_path;
    } else
      g_free(gff_path);
    fclose(ff);
  } else {
    /* We failed to open it.  If we failed for some reason other than
       "it doesn't exist", return the errno and the pathname, so our
       caller can report the error. */
    if (errno != ENOENT) {
      *gopen_errno_return = errno;
      *gread_errno_return = 0;
      *gpath_return = gff_path;
    } else
      g_free(gff_path);
  }

  /* Construct the pathname of the user's disabled protocols file. */
  ff_path = get_persconffile_path(PROTOCOLS_FILE_NAME, TRUE);

  /* If we already have a list of protocols, discard it. */
  discard_existing_list (&disabled_protos);

  /* Read the user's disabled protocols file, if it exists. */
  *path_return = NULL;
  if ((ff = ws_fopen(ff_path, "r")) != NULL) {
    /* We succeeded in opening it; read it. */
    err = read_disabled_protos_list_file(ff_path, ff, &disabled_protos);
    if (err != 0) {
      /* We had an error reading the file; return the errno and the
         pathname, so our caller can report the error. */
      *open_errno_return = 0;
      *read_errno_return = err;
      *path_return = ff_path;
    } else
      g_free(ff_path);
    fclose(ff);
  } else {
    /* We failed to open it.  If we failed for some reason other than
       "it doesn't exist", return the errno and the pathname, so our
       caller can report the error. */
    if (errno != ENOENT) {
      *open_errno_return = errno;
      *read_errno_return = 0;
      *path_return = ff_path;
    } else
      g_free(ff_path);
  }
}

static int
read_disabled_protos_list_file(const char *ff_path, FILE *ff,
                               GList **flp)
{
  protocol_def *prot;
  int         c;
  char       *prot_name;
  int         prot_name_len;
  int         prot_name_index;
  int         line = 1;


  /* Allocate the protocol name buffer. */
  prot_name_len = INIT_BUF_SIZE;
  prot_name = (char *)g_malloc(prot_name_len + 1);

  for (line = 1; ; line++) {
    /* Lines in a disabled protocol file contain the "filter name" of
       a protocol to be disabled. */

    /* Skip over leading white space, if any. */
    while ((c = getc(ff)) != EOF && g_ascii_isspace(c)) {
      if (c == '\n') {
        /* Blank line. */
        continue;
      }
    }

    if (c == EOF) {
      if (ferror(ff))
        goto error;     /* I/O error */
      else
        break;  /* Nothing more to read */
    }
    ungetc(c, ff);      /* Unread the non-white-space character. */

    /* Get the name of the protocol. */
    prot_name_index = 0;
    for (;;) {
      c = getc(ff);
      if (c == EOF)
        break;  /* End of file, or I/O error */
      if (g_ascii_isspace(c))
        break;  /* Trailing white space, or end of line. */
      if (c == '#')
        break;  /* Start of comment, running to end of line. */
      /* Add this character to the protocol name string. */
      if (prot_name_index >= prot_name_len) {
        /* protocol name buffer isn't long enough; double its length. */
        prot_name_len *= 2;
        prot_name = (char *)g_realloc(prot_name, prot_name_len + 1);
      }
      prot_name[prot_name_index] = c;
      prot_name_index++;
    }

    if (g_ascii_isspace(c) && c != '\n') {
      /* Skip over trailing white space. */
      while ((c = getc(ff)) != EOF && c != '\n' && g_ascii_isspace(c))
        ;
      if (c != EOF && c != '\n' && c != '#') {
        /* Non-white-space after the protocol name; warn about it,
           in case we come up with a reason to use it. */
        g_warning("'%s' line %d has extra stuff after the protocol name.",
                  ff_path, line);
      }
    }
    if (c != EOF && c != '\n') {
      /* Skip to end of line. */
      while ((c = getc(ff)) != EOF && c != '\n')
        ;
    }

    if (c == EOF) {
      if (ferror(ff))
        goto error;     /* I/O error */
      else {
        /* EOF, not error; no newline seen before EOF */
        g_warning("'%s' line %d doesn't have a newline.", ff_path,
                  line);
      }
      break;    /* nothing more to read */
    }

    /* Null-terminate the protocol name. */
    if (prot_name_index >= prot_name_len) {
      /* protocol name buffer isn't long enough; double its length. */
      prot_name_len *= 2;
      prot_name = (char *)g_realloc(prot_name, prot_name_len + 1);
    }
    prot_name[prot_name_index] = '\0';

    /* Add the new protocol to the list of disabled protocols */
    prot         = (protocol_def *) g_malloc(sizeof(protocol_def));
    prot->name   = g_strdup(prot_name);
    *flp = g_list_append(*flp, prot);
  }
  g_free(prot_name);
  return 0;

error:
  g_free(prot_name);
  return errno;
}

/*
 * Disable protocols as per the stored configuration
 */
void
set_disabled_protos_list(void)
{
  gint i;
  GList *fl_ent;
  protocol_def *prot;

  /*
   * assume all protocols are enabled by default
   */
  if (disabled_protos == NULL)
    goto skip;

  fl_ent = g_list_first(disabled_protos);

  while (fl_ent != NULL) {
    prot = (protocol_def *) fl_ent->data;
    i = proto_get_id_by_filter_name(prot->name);
    if (i == -1) {
      /* XXX - complain here? */
    } else {
      if (proto_can_toggle_protocol(i))
        proto_set_decoding(i, FALSE);
    }

    fl_ent = fl_ent->next;
  }

skip:
  if (global_disabled_protos == NULL)
    return;

  fl_ent = g_list_first(global_disabled_protos);

  while (fl_ent != NULL) {
    prot = (protocol_def *) fl_ent->data;
    i = proto_get_id_by_filter_name(prot->name);
    if (i == -1) {
      /* XXX - complain here? */
    } else {
      if (proto_can_toggle_protocol(i)) {
        proto_set_decoding(i, FALSE);
        proto_set_cant_toggle(i);
      }
    }

    fl_ent = fl_ent->next;
  }
}

/*
 * Disable a particular protocol by name
 */

void
proto_disable_proto_by_name(const char *name)
{
    protocol_t *protocol;
    int proto_id;

    proto_id = proto_get_id_by_filter_name(name);
    if (proto_id >= 0 ) {
        protocol = find_protocol_by_id(proto_id);
        if (proto_is_protocol_enabled(protocol) == TRUE) {
            if (proto_can_toggle_protocol(proto_id) == TRUE) {
                proto_set_decoding(proto_id, FALSE);
            }
        }
    }
}

/*
 * Write out a list of disabled protocols.
 *
 * On success, "*pref_path_return" is set to NULL.
 * On error, "*pref_path_return" is set to point to the pathname of
 * the file we tried to read - it should be freed by our caller -
 * and "*errno_return" is set to the error.
 */
void
save_disabled_protos_list(char **pref_path_return, int *errno_return)
{
  gchar       *ff_path, *ff_path_new;
  FILE        *ff;
  gint         i;
  protocol_t  *protocol;
  void        *cookie;

  *pref_path_return = NULL;     /* assume no error */

  ff_path = get_persconffile_path(PROTOCOLS_FILE_NAME, TRUE);

  /* Write to "XXX.new", and rename if that succeeds.
     That means we don't trash the file if we fail to write it out
     completely. */
  ff_path_new = g_strdup_printf("%s.new", ff_path);

  if ((ff = ws_fopen(ff_path_new, "w")) == NULL) {
    *pref_path_return = ff_path;
    *errno_return = errno;
    g_free(ff_path_new);
    return;
  }

  /* Iterate over all the protocols */

  for (i = proto_get_first_protocol(&cookie); i != -1;
       i = proto_get_next_protocol(&cookie)) {

    if (!proto_can_toggle_protocol(i)) {
      continue;
    }

    protocol = find_protocol_by_id(i);
    if (proto_is_protocol_enabled(protocol)) {
      continue;
    }

    /* Write out the protocol name. */
    fprintf(ff, "%s\n", proto_get_protocol_filter_name(i));
  }

  if (fclose(ff) == EOF) {
    *pref_path_return = ff_path;
    *errno_return = errno;
    ws_unlink(ff_path_new);
    g_free(ff_path_new);
    return;
  }

#ifdef _WIN32
  /* ANSI C doesn't say whether "rename()" removes the target if it
     exists; the Win32 call to rename files doesn't do so, which I
     infer is the reason why the MSVC++ "rename()" doesn't do so.
     We must therefore remove the target file first, on Windows.

     XXX - ws_rename() should be ws_stdio_rename() on Windows,
     and ws_stdio_rename() uses MoveFileEx() with MOVEFILE_REPLACE_EXISTING,
     so it should remove the target if it exists, so this stuff
     shouldn't be necessary.  Perhaps it dates back to when we were
     calling rename(), with that being a wrapper around Microsoft's
     _rename(), which didn't remove the target. */
  if (ws_remove(ff_path) < 0 && errno != ENOENT) {
    /* It failed for some reason other than "it's not there"; if
       it's not there, we don't need to remove it, so we just
       drive on. */
    *pref_path_return = ff_path;
    *errno_return = errno;
    ws_unlink(ff_path_new);
    g_free(ff_path_new);
    return;
  }
#endif

  if (ws_rename(ff_path_new, ff_path) < 0) {
    *pref_path_return = ff_path;
    *errno_return = errno;
    ws_unlink(ff_path_new);
    g_free(ff_path_new);
    return;
  }
  g_free(ff_path_new);
  g_free(ff_path);
}

void
set_disabled_heur_dissector_list(void)
{
  GList *fl_ent;
  heur_protocol_def *heur;
  heur_dtbl_entry_t* h;

  if (disabled_heuristics == NULL)
    goto skip;

  fl_ent = g_list_first(disabled_heuristics);

  while (fl_ent != NULL) {
    heur = (heur_protocol_def *) fl_ent->data;
    h = find_heur_dissector_by_unique_short_name(heur->name);
    if (h != NULL) {
      h->enabled = heur->enabled;
    }

    fl_ent = fl_ent->next;
  }

skip:
  if (global_disabled_heuristics == NULL)
    return;

  fl_ent = g_list_first(global_disabled_heuristics);

  while (fl_ent != NULL) {
    heur = (heur_protocol_def *) fl_ent->data;

    h = find_heur_dissector_by_unique_short_name(heur->name);
    if (h != NULL) {
      h->enabled = heur->enabled;
    }

    fl_ent = fl_ent->next;
  }
}

static int
read_disabled_heur_dissector_list_file(const char *ff_path, FILE *ff,
                               GList **flp)
{
  heur_protocol_def *heur;
  int         c;
  char       *heuristic_name;
  int         heuristic_name_len;
  int         name_index;
  gboolean    parse_enabled;
  gboolean    enabled;
  int         line = 1;


  /* Allocate the protocol name buffer. */
  heuristic_name_len = INIT_BUF_SIZE;
  heuristic_name = (char *)g_malloc(heuristic_name_len + 1);

  for (line = 1; ; line++) {
    /* Lines in a disabled protocol file contain the "filter name" of
       a protocol to be disabled. */

    /* Skip over leading white space, if any. */
    while ((c = getc(ff)) != EOF && g_ascii_isspace(c)) {
      if (c == '\n') {
        /* Blank line. */
        continue;
      }
    }

    if (c == EOF) {
      if (ferror(ff))
        goto error;     /* I/O error */
      else
        break;  /* Nothing more to read */
    }
    ungetc(c, ff);      /* Unread the non-white-space character. */

    /* Get the name of the protocol. */
    name_index = 0;
    enabled = FALSE;
    parse_enabled = FALSE;
    for (;;) {
      c = getc(ff);
      if (c == EOF)
        break;  /* End of file, or I/O error */
      if (g_ascii_isspace(c))
        break;  /* Trailing white space, or end of line. */
      if (c == ',') {/* Separator for enable/disable */
        parse_enabled = TRUE;
        continue;
      }
      if (c == '#')
        break;  /* Start of comment, running to end of line. */
      if (parse_enabled) {
          enabled = ((c == '1') ? TRUE : FALSE);
          break;
      }
      /* Add this character to the protocol name string. */
      if (name_index >= heuristic_name_len) {
        /* protocol name buffer isn't long enough; double its length. */
        heuristic_name_len *= 2;
        heuristic_name = (char *)g_realloc(heuristic_name, heuristic_name_len + 1);
      }
      heuristic_name[name_index] = c;
      name_index++;
    }

    if (g_ascii_isspace(c) && c != '\n') {
      /* Skip over trailing white space. */
      while ((c = getc(ff)) != EOF && c != '\n' && g_ascii_isspace(c))
        ;
      if (c != EOF && c != '\n' && c != '#') {
        /* Non-white-space after the protocol name; warn about it,
           in case we come up with a reason to use it. */
        g_warning("'%s' line %d has extra stuff after the protocol name.",
                  ff_path, line);
      }
    }
    if (c != EOF && c != '\n') {
      /* Skip to end of line. */
      while ((c = getc(ff)) != EOF && c != '\n')
        ;
    }

    if (c == EOF) {
      if (ferror(ff))
        goto error;     /* I/O error */
      else {
        /* EOF, not error; no newline seen before EOF */
        g_warning("'%s' line %d doesn't have a newline.", ff_path,
                  line);
      }
      break;    /* nothing more to read */
    }

    /* Null-terminate the protocol name. */
    if (name_index >= heuristic_name_len) {
      /* protocol name buffer isn't long enough; double its length. */
      heuristic_name_len *= 2;
      heuristic_name = (char *)g_realloc(heuristic_name, heuristic_name_len + 1);
    }
    heuristic_name[name_index] = '\0';

    /* Add the new protocol to the list of disabled protocols */
    heur         = (heur_protocol_def *) g_malloc(sizeof(heur_protocol_def));
    heur->name   = g_strdup(heuristic_name);
    heur->enabled = enabled;
    *flp = g_list_append(*flp, heur);
  }
  g_free(heuristic_name);
  return 0;

error:
  g_free(heuristic_name);
  return errno;
}

void
read_disabled_heur_dissector_list(char **gpath_return, int *gopen_errno_return,
			  int *gread_errno_return,
			  char **path_return, int *open_errno_return,
			  int *read_errno_return)
{
  int         err;
  char       *gff_path, *ff_path;
  FILE       *ff;

  /* Construct the pathname of the global disabled heuristic dissectors file. */
  gff_path = get_datafile_path(HEURISTICS_FILE_NAME);

  /* If we already have a list of protocols, discard it. */
  heur_discard_existing_list(&global_disabled_heuristics);

  /* Read the global disabled protocols file, if it exists. */
  *gpath_return = NULL;
  if ((ff = ws_fopen(gff_path, "r")) != NULL) {
    /* We succeeded in opening it; read it. */
    err = read_disabled_heur_dissector_list_file(gff_path, ff,
                                         &global_disabled_heuristics);
    if (err != 0) {
      /* We had an error reading the file; return the errno and the
         pathname, so our caller can report the error. */
      *gopen_errno_return = 0;
      *gread_errno_return = err;
      *gpath_return = gff_path;
    } else
      g_free(gff_path);
    fclose(ff);
  } else {
    /* We failed to open it.  If we failed for some reason other than
       "it doesn't exist", return the errno and the pathname, so our
       caller can report the error. */
    if (errno != ENOENT) {
      *gopen_errno_return = errno;
      *gread_errno_return = 0;
      *gpath_return = gff_path;
    } else
      g_free(gff_path);
  }

  /* Construct the pathname of the user's disabled protocols file. */
  ff_path = get_persconffile_path(HEURISTICS_FILE_NAME, TRUE);

  /* If we already have a list of protocols, discard it. */
  heur_discard_existing_list (&disabled_heuristics);

  /* Read the user's disabled protocols file, if it exists. */
  *path_return = NULL;
  if ((ff = ws_fopen(ff_path, "r")) != NULL) {
    /* We succeeded in opening it; read it. */
    err = read_disabled_heur_dissector_list_file(ff_path, ff, &disabled_heuristics);
    if (err != 0) {
      /* We had an error reading the file; return the errno and the
         pathname, so our caller can report the error. */
      *open_errno_return = 0;
      *read_errno_return = err;
      *path_return = ff_path;
    } else
      g_free(ff_path);
    fclose(ff);
  } else {
    /* We failed to open it.  If we failed for some reason other than
       "it doesn't exist", return the errno and the pathname, so our
       caller can report the error. */
    if (errno != ENOENT) {
      *open_errno_return = errno;
      *read_errno_return = 0;
      *path_return = ff_path;
    } else
      g_free(ff_path);
  }
}

static gint
heur_compare(gconstpointer a, gconstpointer b)
{
  return strcmp(((heur_dtbl_entry_t*)a)->short_name,
        ((heur_dtbl_entry_t*)b)->short_name);
}

static void
write_heur_dissector(gpointer data, gpointer user_data)
{
  heur_dtbl_entry_t* dtbl_entry = (heur_dtbl_entry_t*)data;
  FILE *ff = (FILE*)user_data;

  /* Write out the heuristic short name and its enabled state */
  fprintf(ff, "%s,%d\n", dtbl_entry->short_name, dtbl_entry->enabled ? 1 : 0);
}

static void
sort_dissector_table_entries(const char *table_name _U_,
    heur_dtbl_entry_t *dtbl_entry, gpointer user_data)
{
  GSList **list = (GSList**)user_data;
  *list = g_slist_insert_sorted(*list, dtbl_entry, heur_compare);
}

static void
sort_heur_dissector_tables(const char *table_name, struct heur_dissector_list *list, gpointer w)
{
  if (list) {
    heur_dissector_table_foreach(table_name, sort_dissector_table_entries, w);
  }
}

WS_DLL_PUBLIC void
save_disabled_heur_dissector_list(char **pref_path_return, int *errno_return)
{
  gchar       *ff_path, *ff_path_new;
  GSList      *sorted_heur_list = NULL;
  FILE        *ff;

  *pref_path_return = NULL;     /* assume no error */

  ff_path = get_persconffile_path(HEURISTICS_FILE_NAME, TRUE);

  /* Write to "XXX.new", and rename if that succeeds.
     That means we don't trash the file if we fail to write it out
     completely. */
  ff_path_new = g_strdup_printf("%s.new", ff_path);

  if ((ff = ws_fopen(ff_path_new, "w")) == NULL) {
    *pref_path_return = ff_path;
    *errno_return = errno;
    g_free(ff_path_new);
    return;
  }

  /* Iterate over all the heuristic dissectors to sort them in alphabetical order by short name */
  dissector_all_heur_tables_foreach_table(sort_heur_dissector_tables, &sorted_heur_list, NULL);

  /* Write the list */
  g_slist_foreach(sorted_heur_list, write_heur_dissector, ff);
  g_slist_free(sorted_heur_list);

  if (fclose(ff) == EOF) {
    *pref_path_return = ff_path;
    *errno_return = errno;
    ws_unlink(ff_path_new);
    g_free(ff_path_new);
    return;
  }

#ifdef _WIN32
  /* ANSI C doesn't say whether "rename()" removes the target if it
     exists; the Win32 call to rename files doesn't do so, which I
     infer is the reason why the MSVC++ "rename()" doesn't do so.
     We must therefore remove the target file first, on Windows.

     XXX - ws_rename() should be ws_stdio_rename() on Windows,
     and ws_stdio_rename() uses MoveFileEx() with MOVEFILE_REPLACE_EXISTING,
     so it should remove the target if it exists, so this stuff
     shouldn't be necessary.  Perhaps it dates back to when we were
     calling rename(), with that being a wrapper around Microsoft's
     _rename(), which didn't remove the target. */
  if (ws_remove(ff_path) < 0 && errno != ENOENT) {
    /* It failed for some reason other than "it's not there"; if
       it's not there, we don't need to remove it, so we just
       drive on. */
    *pref_path_return = ff_path;
    *errno_return = errno;
    ws_unlink(ff_path_new);
    g_free(ff_path_new);
    return;
  }
#endif

  if (ws_rename(ff_path_new, ff_path) < 0) {
    *pref_path_return = ff_path;
    *errno_return = errno;
    ws_unlink(ff_path_new);
    g_free(ff_path_new);
    return;
  }
  g_free(ff_path_new);
  g_free(ff_path);
}

void
proto_enable_heuristic_by_name(const char *name, gboolean enable)
{
  heur_dtbl_entry_t* heur = find_heur_dissector_by_unique_short_name(name);
  if (heur != NULL) {
      heur->enabled = enable;
  }
}

/*
 * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 *
 * 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:
 */