/*

 * ProFTPD - FTP server daemon

 * Copyright (c) 2008-2020 The ProFTPD Project team

 *

 * 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, Suite 500, Boston, MA 02110-1335, USA.

 *

 * As a special exemption, The ProFTPD Project team and other respective

 * copyright holders give permission to link this program with OpenSSL, and

 * distribute the resulting executable, without including the source code for

 * OpenSSL in the source distribution.

 */

/* Expression API implementation */

#include "conf.h"

array_header *pr_expr_create(pool *p, unsigned int *argc, char **argv) {

  array_header *acl = NULL;

  unsigned int cnt;

  char *s, *ent;

  if (p == NULL ||

      argc == NULL ||

      argv == NULL ||

      *argv == NULL) {

    errno = EINVAL;

    return NULL;

  }

  cnt = *argc;

  if (cnt > 0) {

    acl = make_array(p, cnt, sizeof(char *));

    /* Skip past the first string in argv, as this is usually the directive. */

    while (cnt-- && *(++argv)) {

      char *sep = ",";

      s = pstrdup(p, *argv);

      if (strstr(s, sep) != NULL) {

        while ((ent = pr_str_get_token(&s, sep)) != NULL) {

          pr_signals_handle();

          if (*ent) {

            *((char **) push_array(acl)) = ent;

          }

        }

      } else {

        *((char **) push_array(acl)) = s;

      }

    }

    *argc = acl->nelts;

  } else {

    acl = make_array(p, 0, sizeof(char *));

    *argc = 0;

  }

  return acl;

}

/* Boolean "class-expression" AND matching, returns TRUE if the expression

 * evaluates to TRUE.

 */

int pr_expr_eval_class_and(char **expr) {

  if (expr == NULL ||

      *expr == NULL) {

    errno = EINVAL;

    return -1;

  }

  for (; *expr; expr++) {

    char *class;

    int found;

    class = *expr;

    found = FALSE;

    if (*class == '!') {

      found = !found;

      class++;

    }

    if (session.conn_class == NULL &&

        !found) {

      return FALSE;

    }

    if (session.conn_class != NULL &&

        strcmp(session.conn_class->cls_name, class) == 0) {

      found = !found;

    }

    if (!found) {

      return FALSE;

    }

  }

  return TRUE;

}

/* Boolean "class-expression" OR matching, returns TRUE if the expression

 * evaluates to TRUE.

 */

int pr_expr_eval_class_or(char **expr) {

  if (expr == NULL ||

      *expr == NULL) {

    errno = EINVAL;

    return -1;

  }

  for (; *expr; expr++) {

    char *class;

    int found;

    class = *expr;

    found = FALSE;

    if (*class == '!') {

      found = !found;

      class++;

    }

    if (session.conn_class == NULL) {

      return found;

    }

    if (strcmp(session.conn_class->cls_name, class) == 0) {

      found = !found;

    }

    if (found) {

      return TRUE;

    }

  }

  return FALSE;

}

/* Boolean "group-expression" AND matching, returns TRUE if the expression

 * evaluates to TRUE.

 */

int pr_expr_eval_group_and(char **expr) {

  if (expr == NULL ||

      *expr == NULL) {

    errno = EINVAL;

    return -1;

  }

  for (; *expr; expr++) {

    char *grp;

    int found;

    grp = *expr;

    found = FALSE;

    if (*grp == '!') {

      found = !found;

      grp++;

    }

    if (session.group &&

        strcmp(session.group, grp) == 0) {

      found = !found;

    } else if (session.groups) {

      register unsigned int i = 0;

      char **elts = session.groups->elts;

      for (i = 0; i < session.groups->nelts; i++) {

        if (elts[i] != NULL &&

            strcmp(elts[i], grp) == 0) {

          found = !found;

          break;

        }

      }

    }

    if (!found) {

      return FALSE;

    }

  }

  return TRUE;

}

/* Boolean "group-expression" OR matching, returns TRUE if the expression

 * evaluates to TRUE.

 */

int pr_expr_eval_group_or(char **expr) {

  if (expr == NULL ||

      *expr == NULL) {

    errno = EINVAL;

    return -1;

  }

  for (; *expr; expr++) {

    char *grp;

    int found;

    grp = *expr;

    found = FALSE;

    if (*grp == '!') {

      found = !found;

      grp++;

    }

    if (session.group &&

        strcmp(session.group, grp) == 0) {

      found = !found;

    } else if (session.groups) {

      register unsigned int i = 0;

      char **elts = session.groups->elts;

      for (i = 0; i < session.groups->nelts; i++) {

        if (elts[i] != NULL &&

            strcmp(elts[i], grp) == 0) {

          found = !found;

          break;

        }

      }

    }

    if (found) {

      return TRUE;

    }

  }

  return FALSE;

}

/* Boolean "user-expression" AND matching, returns TRUE if the expression

 * evaluates to TRUE.

 */

int pr_expr_eval_user_and(char **expr) {

  if (expr == NULL ||

      *expr == NULL) {

    errno = EINVAL;

    return -1;

  }

  for (; *expr; expr++) {

    char *user;

    int found;

    user = *expr;

    found = FALSE;

    if (*user == '!') {

      found = !found;

      user++;

    }

    if (session.user != NULL &&

        strcmp(session.user, user) == 0) {

      found = !found;

    }

    if (!found) {

      return FALSE;

    }

  }

  return TRUE;

}

/* Boolean "user-expression" OR matching, returns TRUE if the expression

 * evaluates to TRUE.

 */

int pr_expr_eval_user_or(char **expr) {

  if (expr == NULL ||

      *expr == NULL) {

    errno = EINVAL;

    return -1;

  }

  for (; *expr; expr++) {

    char *user;

    int found = FALSE;

    user = *expr;

    if (*user == '!') {

      found = !found;

      user++;

    }

    if (session.user != NULL &&

        strcmp(session.user, user) == 0) {

      found = !found;

    }

    if (found) {

      return TRUE;

    }

  }

  return FALSE;

}