/*

 * SPDX-License-Identifier: ISC

 *

 * Copyright (c) 2019, 2022 Todd C. Miller <Todd.Miller@sudo.ws>

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include <config.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sudoers.h>

/*

 * Convert struct list_members to a comma-separated string with

 * the given variable name.  Escapes backslashes and commas.

 */

char *

serialize_list(const char *varname, struct list_members *members)

{

    struct list_member *lm, *next;

    size_t len, result_size;

    char *cp, *result;

    debug_decl(serialize_list, SUDOERS_DEBUG_PLUGIN);

    result_size = strlen(varname) + 1;

    SLIST_FOREACH(lm, members, entries) {

  for (cp = lm->value; *cp != '\0'; cp++) {

      result_size++;

      if (*cp == '\\' || *cp == ',')

    result_size++;

  }

  result_size++;

    }

    if ((result = malloc(result_size)) == NULL)

  goto bad;

    /* No need to check len for overflow here. */

    len = strlcpy(result, varname, result_size);

    result[len++] = '=';

    SLIST_FOREACH_SAFE(lm, members, entries, next) {

  for (cp = lm->value; *cp != '\0'; cp++) {

      bool escape = (*cp == '\\' || *cp == ',');

      if (len + 1 + escape >= result_size) {

    sudo_warnx(U_("internal error, %s overflow"), __func__);

    goto bad;

      }

      if (escape)

    result[len++] = '\\';

      result[len++] = *cp;

  }

  if (next != NULL) {

      if (len + 1 >= result_size) {

    sudo_warnx(U_("internal error, %s overflow"), __func__);

    goto bad;

      }

      result[len++] = ',';

  }

  result[len] = '\0';

    }

    debug_return_str(result);

bad:

    free(result);

    debug_return_str(NULL);

}