/src/sudo/plugins/sudoers/match.c

Source
/*
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) 1996, 1998-2005, 2007-2023, 2025
 *  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.
 *
 * Sponsored in part by the Defense Advanced Research Projects
 * Agency (DARPA) and Air Force Research Laboratory, Air Force
 * Materiel Command, USAF, under agreement number F39502-99-1-0512.
 */

#include <config.h>

#include <sys/stat.h>
#ifdef HAVE_SYS_SYSTEMINFO_H
# include <sys/systeminfo.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif /* HAVE_STRINGS_H */
#include <unistd.h>
#ifdef HAVE_NETGROUP_H
# include <netgroup.h>
#else
# include <netdb.h>
#endif /* HAVE_NETGROUP_H */
#include <dirent.h>
#include <fcntl.h>
#include <pwd.h>
#include <grp.h>
#include <errno.h>
#ifdef HAVE_FNMATCH
# include <fnmatch.h>
#else
# include <compat/fnmatch.h>
#endif /* HAVE_FNMATCH */

#include <sudoers.h>
#include <gram.h>

/*
 * Check whether user described by pw matches member.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
user_matches(const struct sudoers_parse_tree *parse_tree,
    const struct passwd *pw, const struct member *m)
{
    const struct sudoers_context *ctx = parse_tree->ctx;
    const char *lhost = parse_tree->lhost ? parse_tree->lhost : ctx->runas.host;
    const char *shost = parse_tree->shost ? parse_tree->shost : ctx->runas.shost;
    int matched = UNSPEC;
    struct alias *a;
    debug_decl(user_matches, SUDOERS_DEBUG_MATCH);

    switch (m->type) {
  case ALL:
      matched = m->negated ? DENY : ALLOW;
      break;
  case NETGROUP:
      if (netgr_matches(parse_tree->nss, m->name,
    def_netgroup_tuple ? lhost : NULL,
    def_netgroup_tuple ? shost : NULL, pw->pw_name) == ALLOW)
    matched = m->negated ? DENY : ALLOW;
      break;
  case USERGROUP:
      if (usergr_matches(m->name, pw->pw_name, pw) == ALLOW)
    matched = m->negated ? DENY : ALLOW;
      break;
  case ALIAS:
      if ((a = alias_get(parse_tree, m->name, USERALIAS)) != NULL) {
    /* XXX */
    const int rc = userlist_matches(parse_tree, pw, &a->members);
    if (SPECIFIED(rc)) {
        if (m->negated) {
      matched = rc == ALLOW ? DENY : ALLOW;
        } else {
      matched = rc;
        }
    }
    alias_put(a);
    break;
      }
      FALLTHROUGH;
  case WORD:
      if (userpw_matches(m->name, pw->pw_name, pw) == ALLOW)
    matched = m->negated ? DENY : ALLOW;
      break;
    }
    debug_return_int(matched);
}

/*
 * Check for user described by pw in a list of members.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
userlist_matches(const struct sudoers_parse_tree *parse_tree,
    const struct passwd *pw, const struct member_list *list)
{
    struct member *m;
    int matched = UNSPEC;
    debug_decl(userlist_matches, SUDOERS_DEBUG_MATCH);

    TAILQ_FOREACH_REVERSE(m, list, member_list, entries) {
  matched = user_matches(parse_tree, pw, m);
  if (SPECIFIED(matched))
      break;
    }
    debug_return_int(matched);
}

struct gid_list *
runas_getgroups(const struct sudoers_context *ctx)
{
    const struct passwd *pw;
    debug_decl(runas_getgroups, SUDOERS_DEBUG_MATCH);

    if (def_preserve_groups) {
  sudo_gidlist_addref(ctx->user.gid_list);
  debug_return_ptr(ctx->user.gid_list);
    }

    /* Only use results from a group db query, not the front end. */
    pw = ctx->runas.pw ? ctx->runas.pw : ctx->user.pw;
    debug_return_ptr(sudo_get_gidlist(pw, ENTRY_TYPE_QUERIED));
}

/*
 * Check whether the requested runas user matches user_list, the
 * user portion of a sudoers runaslist.  If user_list is NULL, a
 * list containing runas_default is used.
 * Returns ALLOW, DENY or UNSPEC.
 */
static int
runas_userlist_matches(const struct sudoers_parse_tree *parse_tree,
    const struct member_list *user_list)
{
    const struct sudoers_context *ctx = parse_tree->ctx;
    const char *lhost = parse_tree->lhost ? parse_tree->lhost : ctx->runas.host;
    const char *shost = parse_tree->shost ? parse_tree->shost : ctx->runas.shost;
    int user_matched = UNSPEC;
    struct member *m;
    struct alias *a;
    debug_decl(runas_userlist_matches, SUDOERS_DEBUG_MATCH);

    TAILQ_FOREACH_REVERSE(m, user_list, member_list, entries) {
  switch (m->type) {
      case ALL:
    user_matched = m->negated ? DENY : ALLOW;
    break;
      case NETGROUP:
    if (netgr_matches(parse_tree->nss, m->name,
        def_netgroup_tuple ? lhost : NULL,
        def_netgroup_tuple ? shost : NULL,
        ctx->runas.pw->pw_name) == ALLOW)
        user_matched = m->negated ? DENY : ALLOW;
    break;
      case USERGROUP:
    if (usergr_matches(m->name, ctx->runas.pw->pw_name, ctx->runas.pw) == ALLOW)
        user_matched = m->negated ? DENY : ALLOW;
    break;
      case ALIAS:
    a = alias_get(parse_tree, m->name, RUNASALIAS);
    if (a != NULL) {
        const int rc = runas_userlist_matches(parse_tree,
      &a->members);
        if (SPECIFIED(rc)) {
      if (m->negated) {
          user_matched = rc == ALLOW ? DENY : ALLOW;
      } else {
          user_matched = rc;
      }
        }
        alias_put(a);
        break;
    }
    FALLTHROUGH;
      case WORD:
    if (userpw_matches(m->name, ctx->runas.pw->pw_name, ctx->runas.pw) == ALLOW)
        user_matched = m->negated ? DENY : ALLOW;
    break;
      case MYSELF:
    /*
     * Only match a rule with an empty runas user if a group
     * was specified on the command line without a user _or_
     * the user specified their own name on the command line.
     */
    if ((!ISSET(ctx->settings.flags, RUNAS_USER_SPECIFIED) &&
      ISSET(ctx->settings.flags, RUNAS_GROUP_SPECIFIED)) ||
      strcmp(ctx->user.name, ctx->runas.pw->pw_name) == 0)
        user_matched = m->negated ? DENY : ALLOW;
    break;
  }
  if (SPECIFIED(user_matched))
      break;
    }
    debug_return_int(user_matched);
}

/*
 * Check whether the requested runas group matches group_list, the
 * group portion of a sudoers runaslist, or the runas user's groups.
 * Returns ALLOW, DENY or UNSPEC.
 */
static int
runas_grouplist_matches(const struct sudoers_parse_tree *parse_tree,
    const struct member_list *group_list, int user_matched)
{
    const struct sudoers_context *ctx = parse_tree->ctx;
    int group_matched = UNSPEC;
    struct member *m;
    struct alias *a;
    debug_decl(runas_grouplist_matches, SUDOERS_DEBUG_MATCH);

    if (group_list != NULL) {
  TAILQ_FOREACH_REVERSE(m, group_list, member_list, entries) {
      switch (m->type) {
    case ALL:
        group_matched = m->negated ? DENY : ALLOW;
        break;
    case ALIAS:
        a = alias_get(parse_tree, m->name, RUNASALIAS);
        if (a != NULL) {
      const int rc = runas_grouplist_matches(parse_tree,
          &a->members, user_matched);
      if (SPECIFIED(rc)) {
          if (m->negated) {
        group_matched = rc == ALLOW ? DENY : ALLOW;
          } else {
        group_matched = rc;
          }
      }
      alias_put(a);
      break;
        }
        FALLTHROUGH;
    case WORD:
        if (group_matches(m->name, ctx->runas.gr) == ALLOW)
      group_matched = m->negated ? DENY : ALLOW;
        break;
      }
      if (SPECIFIED(group_matched))
    break;
  }
    }
    if (!SPECIFIED(group_matched) && user_matched == ALLOW) {
  struct gid_list *runas_groups;
  /*
   * The runas group was not explicitly allowed by sudoers.
   * If the runas user matched, check its group list too.
   */
  if (ctx->runas.pw->pw_gid == ctx->runas.gr->gr_gid) {
      group_matched = ALLOW; /* runas group matches passwd db */
  } else if ((runas_groups = runas_getgroups(ctx)) != NULL) {
      int i;

      for (i = 0; i < runas_groups->ngids; i++) {
    if (runas_groups->gids[i] == ctx->runas.gr->gr_gid) {
        group_matched = ALLOW; /* matched aux group vector */
        break;
    }
      }
      sudo_gidlist_delref(runas_groups);
  }
    }

    debug_return_int(group_matched);
}

/*
 * Check whether the sudoers runaslist, composed of user_list and
 * group_list, matches the runas user/group requested by the user.
 * Either (or both) user_list and group_list may be NULL.
 * If user_list is NULL, a list containing runas_default is used.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
runaslist_matches(const struct sudoers_parse_tree *parse_tree,
    const struct member_list *user_list, const struct member_list *group_list)
{
    const struct sudoers_context *ctx = parse_tree->ctx;
    struct member_list _user_list = TAILQ_HEAD_INITIALIZER(_user_list);
    int user_matched, group_matched = UNSPEC;
    struct member m_user;
    debug_decl(runaslist_matches, SUDOERS_DEBUG_MATCH);

    /* If no runas user listed in sudoers, use the default value.  */
    if (user_list == NULL) {
  m_user.name = def_runas_default;
  m_user.type = WORD;
  m_user.negated = false;
  TAILQ_INSERT_HEAD(&_user_list, &m_user, entries);
  user_list = &_user_list;
    }

    user_matched = runas_userlist_matches(parse_tree, user_list);
    if (ISSET(ctx->settings.flags, RUNAS_GROUP_SPECIFIED)) {
  group_matched = runas_grouplist_matches(parse_tree, group_list,
      user_matched);
  /*
   * Allow "sudo -g group" or "sudo -u myname -g group"
   * if the runas group matches.
   */
  if (group_matched == ALLOW && user_matched == UNSPEC) {
      if (strcmp(ctx->user.name, ctx->runas.pw->pw_name) == 0)
    user_matched = ALLOW;
  }
    }

    if (user_matched == DENY || group_matched == DENY)
  debug_return_int(DENY);
    if (user_matched == group_matched || ctx->runas.gr == NULL)
  debug_return_int(user_matched);
    debug_return_int(UNSPEC);
}

/*
 * Check for lhost and shost in a list of members.
 * Returns ALLOW, DENY or UNSPEC.
 */
static int
hostlist_matches_int(const struct sudoers_parse_tree *parse_tree,
    const struct passwd *pw, const char *lhost, const char *shost,
    const struct member_list *list)
{
    struct member *m;
    int matched = UNSPEC;
    debug_decl(hostlist_matches, SUDOERS_DEBUG_MATCH);

    TAILQ_FOREACH_REVERSE(m, list, member_list, entries) {
  matched = host_matches(parse_tree, pw, lhost, shost, m);
  if (SPECIFIED(matched))
      break;
    }
    debug_return_int(matched);
}

/*
 * Check for ctx->runas.host and ctx->runas.shost in a list of members.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
hostlist_matches(const struct sudoers_parse_tree *parse_tree,
    const struct passwd *pw, const struct member_list *list)
{
    const struct sudoers_context *ctx = parse_tree->ctx;
    const char *lhost = parse_tree->lhost ? parse_tree->lhost : ctx->runas.host;
    const char *shost = parse_tree->shost ? parse_tree->shost : ctx->runas.shost;

    return hostlist_matches_int(parse_tree, pw, lhost, shost, list);
}

/*
 * Check whether host or shost matches member.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
host_matches(const struct sudoers_parse_tree *parse_tree,
    const struct passwd *pw, const char *lhost, const char *shost,
    const struct member *m)
{
    struct alias *a;
    int ret = UNSPEC;
    const char *user = NULL;
    debug_decl(host_matches, SUDOERS_DEBUG_MATCH);

    switch (m->type) {
  case ALL:
      ret = m->negated ? DENY : ALLOW;
      break;
  case NETGROUP:
      if (def_netgroup_tuple && pw != NULL)
    user = pw->pw_name;
      if (netgr_matches(parse_tree->nss, m->name, lhost, shost,
        user) == ALLOW) {
    ret = m->negated ? DENY : ALLOW;
      }
      break;
  case NTWKADDR:
      if (addr_matches(m->name) == ALLOW)
    ret = m->negated ? DENY : ALLOW;
      break;
  case ALIAS:
      a = alias_get(parse_tree, m->name, HOSTALIAS);
      if (a != NULL) {
    /* XXX */
    const int rc = hostlist_matches_int(parse_tree, pw, lhost,
        shost, &a->members);
    if (SPECIFIED(rc)) {
        if (m->negated) {
      ret = rc == ALLOW ? DENY : ALLOW;
        } else {
      ret = rc;
        }
    }
    alias_put(a);
    break;
      }
      FALLTHROUGH;
  case WORD:
      if (hostname_matches(shost, lhost, m->name) == ALLOW)
    ret = m->negated ? DENY : ALLOW;
      break;
    }
    sudo_debug_printf(SUDO_DEBUG_DEBUG,
  "host %s (%s) matches sudoers host %s%s: %s", lhost, shost,
  m->negated ? "!" : "", m->name ? m->name : "ALL",
  ret == ALLOW ? "ALLOW" : "DENY");
    debug_return_int(ret);
}

/*
 * Check for cmnd and args in a list of members.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
cmndlist_matches(const struct sudoers_parse_tree *parse_tree,
    const struct member_list *list, const char *runchroot,
    struct cmnd_info *info)
{
    struct member *m;
    int matched;
    debug_decl(cmndlist_matches, SUDOERS_DEBUG_MATCH);

    TAILQ_FOREACH_REVERSE(m, list, member_list, entries) {
  matched = cmnd_matches(parse_tree, m, runchroot, info);
  if (SPECIFIED(matched))
      debug_return_int(matched);
    }
    debug_return_int(UNSPEC);
}

/*
 * Check cmnd and args.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
cmnd_matches(const struct sudoers_parse_tree *parse_tree,
    const struct member *m, const char *runchroot, struct cmnd_info *info)
{
    struct alias *a;
    struct sudo_command *c;
    int rc, matched = UNSPEC;
    debug_decl(cmnd_matches, SUDOERS_DEBUG_MATCH);

    switch (m->type) {
  case ALL:
  case COMMAND:
      c = (struct sudo_command *)m->name;
      if (command_matches(parse_tree->ctx, c->cmnd, c->args, runchroot,
        info, &c->digests) == ALLOW)
    matched = m->negated ? DENY : ALLOW;
      break;
  case ALIAS:
      a = alias_get(parse_tree, m->name, CMNDALIAS);
      if (a != NULL) {
    rc = cmndlist_matches(parse_tree, &a->members, runchroot, info);
    if (SPECIFIED(rc)) {
        if (m->negated) {
      matched = rc == ALLOW ? DENY : ALLOW;
        } else {
      matched = rc;
        }
    }
    alias_put(a);
      }
      break;
    }
    debug_return_int(matched);
}

/*
 * Like cmnd_matches() but only matches against the ALL command.
 * Returns ALLOW, DENY or UNSPEC.
 */
int
cmnd_matches_all(const struct sudoers_parse_tree *parse_tree,
    const struct member *m, const char *runchroot, struct cmnd_info *info)
{
    const bool negated = m->negated;
    struct sudo_command *c;
    int matched = UNSPEC;
    struct alias *a;
    debug_decl(cmnd_matches_all, SUDOERS_DEBUG_MATCH);

    switch (m->type) {
  case ALL:
      c = (struct sudo_command *)m->name;
      if (command_matches(parse_tree->ctx, c->cmnd, c->args, runchroot,
        info, &c->digests) == ALLOW)
    matched = negated ? DENY : ALLOW;
      break;
  case ALIAS:
      a = alias_get(parse_tree, m->name, CMNDALIAS);
      if (a != NULL) {
    TAILQ_FOREACH_REVERSE(m, &a->members, member_list, entries) {
        matched = cmnd_matches_all(parse_tree, m, runchroot, info);
        if (SPECIFIED(matched)) {
      if (negated)
          matched = matched == ALLOW ? DENY : ALLOW;
      break;
        }
    }
    alias_put(a);
      }
      break;
    }
    debug_return_int(matched);
}

/*
 * Returns ALLOW if the hostname matches the pattern, else DENY
 */
int
hostname_matches(const char *shost, const char *lhost, const char *pattern)
{
    const char *host;
    int ret;
    debug_decl(hostname_matches, SUDOERS_DEBUG_MATCH);

    host = strchr(pattern, '.') != NULL ? lhost : shost;
    ret = DENY;
    if (has_meta(pattern)) {
  if (fnmatch(pattern, host, FNM_CASEFOLD) == 0)
      ret = ALLOW;
    } else {
  if (strcasecmp(host, pattern) == 0)
      ret = ALLOW;
    }
    debug_return_int(ret);
}

/*
 * Returns ALLOW if the user/uid from sudoers matches the specified user/uid,
 * else returns DENY.
 */
int
userpw_matches(const char *sudoers_user, const char *user, const struct passwd *pw)
{
    const char *errstr;
    int ret = DENY;
    uid_t uid;
    debug_decl(userpw_matches, SUDOERS_DEBUG_MATCH);

    if (pw != NULL && *sudoers_user == '#') {
  uid = (uid_t) sudo_strtoid(sudoers_user + 1, &errstr);
  if (errstr == NULL && uid == pw->pw_uid) {
      ret = ALLOW;
      goto done;
  }
    }
    if (def_case_insensitive_user) {
  if (strcasecmp(sudoers_user, user) == 0)
      ret = ALLOW;
    } else {
  if (strcmp(sudoers_user, user) == 0)
      ret = ALLOW;
    }
done:
    sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
  "user %s matches sudoers user %s: %s",
  user, sudoers_user, ret == ALLOW ? "ALLOW" : "DENY");
    debug_return_int(ret);
}

/*
 * Returns ALLOW if the group/gid from sudoers matches the specified group/gid,
 * else returns DENY.
 */
int
group_matches(const char *sudoers_group, const struct group *gr)
{
    const char *errstr;
    int ret = DENY;
    gid_t gid;
    debug_decl(group_matches, SUDOERS_DEBUG_MATCH);

    if (*sudoers_group == '#') {
  gid = (gid_t) sudo_strtoid(sudoers_group + 1, &errstr);
  if (errstr == NULL && gid == gr->gr_gid) {
      ret = ALLOW;
      goto done;
  }
    }
    if (def_case_insensitive_group) {
  if (strcasecmp(sudoers_group, gr->gr_name) == 0)
      ret = ALLOW;
    } else {
  if (strcmp(sudoers_group, gr->gr_name) == 0)
      ret = ALLOW;
    }
done:
    sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
  "group %s matches sudoers group %s: %s",
  gr->gr_name, sudoers_group, ret == ALLOW ? "ALLOW" : "DENY");
    debug_return_int(ret);
}

/*
 * Returns true if the given user belongs to the named group,
 * else returns false.
 */
int
usergr_matches(const char *group, const char *user, const struct passwd *pw)
{
    struct passwd *pw0 = NULL;
    int ret = DENY;
    debug_decl(usergr_matches, SUDOERS_DEBUG_MATCH);

    /* Make sure we have a valid usergroup, sudo style */
    if (*group++ != '%') {
  sudo_debug_printf(SUDO_DEBUG_DIAG, "user group %s has no leading '%%'",
      group);
  goto done;
    }

    /* Query group plugin for %:name groups. */
    if (*group == ':' && def_group_plugin) {
  if (group_plugin_query(user, group + 1, pw) == true)
      ret = ALLOW;
  goto done;
    }

    /* Look up user's primary gid in the passwd file. */
    if (pw == NULL) {
  if ((pw0 = sudo_getpwnam(user)) == NULL) {
      sudo_debug_printf(SUDO_DEBUG_DIAG, "unable to find %s in passwd db",
    user);
      goto done;
  }
  pw = pw0;
    }

    if (user_in_group(pw, group)) {
  ret = ALLOW;
  goto done;
    }

    /* Query the group plugin for Unix groups too? */
    if (def_group_plugin && def_always_query_group_plugin) {
  if (group_plugin_query(user, group, pw) == true) {
      ret = ALLOW;
      goto done;
  }
    }

done:
    if (pw0 != NULL)
  sudo_pw_delref(pw0);

    sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
  "user %s matches group %s: %s", user, group,
  ret == ALLOW ? "ALLOW" : "DENY");
    debug_return_int(ret);
}

#if defined(HAVE_GETDOMAINNAME) || defined(SI_SRPC_DOMAIN)
/*
 * Check the domain for invalid characters.
 * Linux getdomainname(2) returns (none) if no domain is set.
 */
static bool
valid_domain(const char *domain)
{
    const char *cp;
    debug_decl(valid_domain, SUDOERS_DEBUG_MATCH);

    for (cp = domain; *cp != '\0'; cp++) {
  /* Check for illegal characters, Linux may use "(none)". */
  if (*cp == '(' || *cp == ')' || *cp == ',' || *cp == ' ')
      break;
    }
    if (cp == domain || *cp != '\0')
  debug_return_bool(false);
    debug_return_bool(true);
}

/*
 * Get NIS-style domain name and copy from static storage or NULL if none.
 */
const char *
sudo_getdomainname(void)
{
    static char *domain;
    static bool initialized;
    debug_decl(sudo_getdomainname, SUDOERS_DEBUG_MATCH);

    if (!initialized) {
  const size_t host_name_max = sudo_host_name_max();
  int rc;

  domain = malloc(host_name_max + 1);
  if (domain != NULL) {
      domain[0] = '\0';
# ifdef SI_SRPC_DOMAIN
      rc = sysinfo(SI_SRPC_DOMAIN, domain, host_name_max + 1);
# else
      rc = getdomainname(domain, host_name_max + 1);
# endif
      if (rc == -1 || !valid_domain(domain)) {
    /* Error or invalid domain name. */
    free(domain);
    domain = NULL;
      }
  } else {
      /* XXX - want to pass error back to caller */
      sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
    "unable to allocate memory");
  }
  initialized = true;
    }
    debug_return_str(domain);
}
#else
const char *
sudo_getdomainname(void)
{
    debug_decl(sudo_getdomainname, SUDOERS_DEBUG_MATCH);
    debug_return_ptr(NULL);
}
#endif /* HAVE_GETDOMAINNAME || SI_SRPC_DOMAIN */

/*
 * Returns ALLOW if "host" and "user" belong to the netgroup "netgr",
 * else return DENY.  Either of "lhost", "shost" or "user" may be NULL
 * in which case that argument is not checked...
 */
int
netgr_matches(const struct sudo_nss *nss, const char *netgr,
    const char *lhost, const char *shost, const char *user)
{
    const char *domain;
    int ret = DENY;
    debug_decl(netgr_matches, SUDOERS_DEBUG_MATCH);

    if (!def_use_netgroups) {
  sudo_debug_printf(SUDO_DEBUG_INFO, "netgroups are disabled");
  debug_return_int(DENY);
    }

    /* make sure we have a valid netgroup, sudo style */
    if (*netgr++ != '+') {
  sudo_debug_printf(SUDO_DEBUG_DIAG, "netgroup %s has no leading '+'",
      netgr);
  debug_return_int(DENY);
    }

    /* get the domain name (if any) */
    domain = sudo_getdomainname();

    /* Use nss-specific innetgr() function if available. */
    if (nss != NULL && nss->innetgr != NULL) {
  switch (nss->innetgr(nss, netgr, lhost, user, domain)) {
  case 0:
      if (lhost != shost) {
    if (nss->innetgr(nss, netgr, shost, user, domain) == 1)
        ret = ALLOW;
      }
      goto done;
  case 1:
      ret = ALLOW;
      goto done;
  default:
      /* Not supported, use system innetgr(3). */
      break;
  }
    }

#ifdef HAVE_INNETGR
    /* Use system innetgr() function. */
    if (innetgr(netgr, lhost, user, domain) == 1) {
  ret = ALLOW;
    } else if (lhost != shost) {
  if (innetgr(netgr, shost, user, domain) == 1)
      ret = ALLOW;
    }
#else
    sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO,
  "%s: no system netgroup support", __func__);
#endif /* HAVE_INNETGR */

done:
    sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
  "netgroup %s matches (%s|%s, %s, %s): %s", netgr, lhost ? lhost : "",
  shost ? shost : "", user ? user : "", domain ? domain : "",
  ret == ALLOW ? "ALLOW" : "DENY");

    debug_return_int(ret);
}

Coverage Report

Created: 2026-10-17 06:18