Adding upstream version 1.9.15p5.upstream/1.9.15p5upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1556 insertions, 0 deletions

diff --git a/plugins/sudoers/sudoers.c b/plugins/sudoers/sudoers.c
new file mode 100644
index 0000000..6778e4e
--- /dev/null
+++ b/plugins/sudoers/sudoers.c
@@ -0,0 +1,1556 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 1993-1996, 1998-2023 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.
+ */
+
+/*
+ * This is an open source non-commercial project. Dear PVS-Studio, please check it.
+ * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+ */
+
+#ifdef __TANDEM
+# include <floss.h>
+#endif
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <pwd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <netdb.h>
+#ifdef HAVE_LOGIN_CAP_H
+# include <login_cap.h>
+# ifndef LOGIN_DEFROOTCLASS
+#  define LOGIN_DEFROOTCLASS	"daemon"
+# endif
+# ifndef LOGIN_SETENV
+#  define LOGIN_SETENV	0
+# endif
+#endif
+#ifdef HAVE_SELINUX
+# include <selinux/selinux.h>
+#endif
+#include <ctype.h>
+#ifndef HAVE_GETADDRINFO
+# include <compat/getaddrinfo.h>
+#endif
+
+#include <sudoers.h>
+#include <timestamp.h>
+#include <sudo_iolog.h>
+
+/*
+ * Prototypes
+ */
+static int set_cmnd(struct sudoers_context *ctx);
+static bool init_vars(struct sudoers_context *ctx, char * const *);
+static bool set_loginclass(struct sudoers_context *);
+static bool set_runaspw(struct sudoers_context *ctx, const char *, bool);
+static bool set_runasgr(struct sudoers_context *ctx, const char *, bool);
+
+/*
+ * Globals
+ */
+static char *prev_user;
+static struct sudoers_context sudoers_ctx = SUDOERS_CONTEXT_INITIALIZER;
+static struct sudo_nss_list *snl;
+static bool unknown_runas_uid;
+static bool unknown_runas_gid;
+static int cmnd_status = NOT_FOUND_ERROR;
+static struct defaults_list initial_defaults = TAILQ_HEAD_INITIALIZER(initial_defaults);
+
+#ifdef __linux__
+static struct rlimit nproclimit;
+#endif
+
+#ifdef SUDOERS_LOG_CLIENT
+# define remote_iologs	(!SLIST_EMPTY(&def_log_servers))
+#else
+# define remote_iologs	0
+#endif
+
+/*
+ * Unlimit the number of processes since Linux's setuid() will
+ * apply resource limits when changing uid and return EAGAIN if
+ * nproc would be exceeded by the uid switch.
+ */
+static void
+unlimit_nproc(void)
+{
+#ifdef __linux__
+    struct rlimit rl;
+    debug_decl(unlimit_nproc, SUDOERS_DEBUG_UTIL);
+
+    if (getrlimit(RLIMIT_NPROC, &nproclimit) != 0)
+	    sudo_warn("getrlimit(RLIMIT_NPROC)");
+    rl.rlim_cur = rl.rlim_max = RLIM_INFINITY;
+    if (setrlimit(RLIMIT_NPROC, &rl) != 0) {
+	rl.rlim_cur = rl.rlim_max = nproclimit.rlim_max;
+	if (setrlimit(RLIMIT_NPROC, &rl) != 0)
+	    sudo_warn("setrlimit(RLIMIT_NPROC)");
+    }
+    debug_return;
+#endif /* __linux__ */
+}
+
+/*
+ * Restore saved value of RLIMIT_NPROC.
+ */
+static void
+restore_nproc(void)
+{
+#ifdef __linux__
+    debug_decl(restore_nproc, SUDOERS_DEBUG_UTIL);
+
+    if (setrlimit(RLIMIT_NPROC, &nproclimit) != 0)
+	sudo_warn("setrlimit(RLIMIT_NPROC)");
+
+    debug_return;
+#endif /* __linux__ */
+}
+
+/*
+ * Re-initialize Defaults settings.
+ * We do not warn, log or send mail for errors when reinitializing,
+ * this would have already been done the first time through.
+ */
+static bool
+sudoers_reinit_defaults(struct sudoers_context *ctx)
+{
+    struct sudo_nss *nss, *nss_next;
+    sudoers_logger_t logger = sudoers_error_hook;
+    debug_decl(sudoers_reinit_defaults, SUDOERS_DEBUG_PLUGIN);
+
+    if (!init_defaults()) {
+	sudo_warnx("%s", U_("unable to initialize sudoers default values"));
+	debug_return_bool(false);
+    }
+
+    /* It should not be possible for the initial defaults to fail to apply. */
+    if (!update_defaults(ctx, NULL, &initial_defaults,
+	    SETDEF_GENERIC|SETDEF_HOST|SETDEF_USER|SETDEF_RUNAS, false))
+	debug_return_bool(false);
+
+    /* Disable error logging while re-processing defaults. */
+    sudoers_error_hook = NULL;
+
+    TAILQ_FOREACH_SAFE(nss, snl, entries, nss_next) {
+	/* Missing/invalid defaults is not a fatal error. */
+	if (nss->getdefs(ctx, nss) != -1) {
+	    (void)update_defaults(ctx, nss->parse_tree, NULL,
+		SETDEF_GENERIC|SETDEF_HOST|SETDEF_USER|SETDEF_RUNAS, true);
+	}
+    }
+
+    /* Restore error logging. */
+    sudoers_error_hook = logger;
+
+    /* No need to check the admin flag file multiple times. */
+    if (ISSET(ctx->mode, MODE_POLICY_INTERCEPTED)) {
+	free(def_admin_flag);
+	def_admin_flag = NULL;
+    }
+
+    debug_return_bool(true);
+}
+
+int
+sudoers_init(void *info, sudoers_logger_t logger, char * const envp[])
+{
+    struct sudo_nss *nss, *nss_next;
+    int oldlocale, sources = 0;
+    static int ret = -1;
+    debug_decl(sudoers_init, SUDOERS_DEBUG_PLUGIN);
+
+    /* Only initialize once. */
+    if (snl != NULL)
+	debug_return_int(ret);
+
+    bindtextdomain("sudoers", LOCALEDIR);
+
+    /* Hook up logging function for parse errors. */
+    sudoers_error_hook = logger;
+
+    /* Register fatal/fatalx callback. */
+    sudo_fatal_callback_register(sudoers_cleanup);
+
+    /* Initialize environment functions (including replacements). */
+    if (!env_init(envp))
+	debug_return_int(-1);
+
+    /* Setup defaults data structures. */
+    if (!init_defaults()) {
+	sudo_warnx("%s", U_("unable to initialize sudoers default values"));
+	debug_return_int(-1);
+    }
+
+    /* Parse info from front-end. */
+    sudoers_ctx.mode = sudoers_policy_deserialize_info(&sudoers_ctx, info,
+	&initial_defaults);
+    if (ISSET(sudoers_ctx.mode, MODE_ERROR))
+	debug_return_int(-1);
+
+    if (!init_vars(&sudoers_ctx, envp))
+	debug_return_int(-1);
+
+    /* Parse nsswitch.conf for sudoers order. */
+    snl = sudo_read_nss();
+
+    /* LDAP or NSS may modify the euid so we need to be root for the open. */
+    if (!set_perms(NULL, PERM_ROOT))
+	debug_return_int(-1);
+
+    /* Use the C locale unless another is specified in sudoers. */
+    sudoers_setlocale(SUDOERS_LOCALE_SUDOERS, &oldlocale);
+    sudo_warn_set_locale_func(sudoers_warn_setlocale);
+
+    /* Update defaults set by front-end. */
+    if (!update_defaults(&sudoers_ctx, NULL, &initial_defaults,
+	    SETDEF_GENERIC|SETDEF_HOST|SETDEF_USER|SETDEF_RUNAS, false)) {
+	goto cleanup;
+    }
+
+    /* Open and parse sudoers, set global defaults.  */
+    TAILQ_FOREACH_SAFE(nss, snl, entries, nss_next) {
+	if (nss->open(&sudoers_ctx, nss) == -1 || (nss->parse_tree = nss->parse(&sudoers_ctx, nss)) == NULL) {
+	    TAILQ_REMOVE(snl, nss, entries);
+	    continue;
+	}
+	sources++;
+
+	/* Missing/invalid defaults is not a fatal error. */
+	if (nss->getdefs(&sudoers_ctx, nss) == -1) {
+	    log_warningx(&sudoers_ctx, SLOG_PARSE_ERROR|SLOG_NO_STDERR,
+		N_("unable to get defaults from %s"), nss->source);
+	} else {
+	    (void)update_defaults(&sudoers_ctx, nss->parse_tree, NULL,
+		SETDEF_GENERIC|SETDEF_HOST|SETDEF_USER|SETDEF_RUNAS, false);
+	}
+    }
+    if (sources == 0) {
+	/* Display an extra warning if there are multiple sudoers sources. */
+	if (TAILQ_FIRST(snl) != TAILQ_LAST(snl, sudo_nss_list))
+	    sudo_warnx("%s", U_("no valid sudoers sources found, quitting"));
+	goto cleanup;
+    }
+
+    /* Set login class if applicable (after sudoers is parsed). */
+    if (set_loginclass(&sudoers_ctx))
+	ret = true;
+
+cleanup:
+    mail_parse_errors(&sudoers_ctx);
+
+    if (!restore_perms())
+	ret = -1;
+
+    /* Restore user's locale. */
+    sudo_warn_set_locale_func(NULL);
+    sudoers_setlocale(oldlocale, NULL);
+
+    debug_return_int(ret);
+}
+
+/*
+ * Expand I/O log dir and file into a full path.
+ * Returns the full I/O log path prefixed with "iolog_path=".
+ * Sets ctx->iolog_file and ctx->iolog_path as a side effect.
+ */
+static char *
+format_iolog_path(struct sudoers_context *ctx)
+{
+    char dir[PATH_MAX], file[PATH_MAX];
+    char *iolog_path = NULL;
+    int oldlocale;
+    bool ok;
+    debug_decl(format_iolog_path, SUDOERS_DEBUG_PLUGIN);
+
+    /* Use sudoers locale for strftime() */
+    sudoers_setlocale(SUDOERS_LOCALE_SUDOERS, &oldlocale);
+    ok = expand_iolog_path(def_iolog_dir, dir, sizeof(dir),
+	&sudoers_iolog_path_escapes[1], ctx);
+    if (ok) {
+	ctx->iolog_dir = dir;
+	ok = expand_iolog_path(def_iolog_file, file, sizeof(file),
+	    &sudoers_iolog_path_escapes[0], ctx);
+	ctx->iolog_dir = NULL;
+    }
+    sudoers_setlocale(oldlocale, NULL);
+    if (!ok)
+	goto done;
+
+    if (asprintf(&iolog_path, "iolog_path=%s/%s", dir, file) == -1) {
+	iolog_path = NULL;
+	goto done;
+    }
+
+    /* Stash pointer to the I/O log for the event log. */
+    ctx->iolog_path = iolog_path + sizeof("iolog_path=") - 1;
+    ctx->iolog_file = ctx->iolog_path + 1 + strlen(dir);
+
+done:
+    debug_return_str(iolog_path);
+}
+
+static void
+cb_lookup(const struct sudoers_parse_tree *parse_tree,
+    const struct userspec *us, int user_match, const struct privilege *priv,
+    int host_match, const struct cmndspec *cs, int date_match, int runas_match,
+    int cmnd_match, void *closure)
+{
+    struct sudoers_match_info *info = closure;
+
+    if (cmnd_match != UNSPEC) {
+	info->us = us;
+	info->priv = priv;
+	info->cs = cs;
+    }
+}
+
+/*
+ * Find the command, perform a sudoers lookup, ask for a password as
+ * needed, and perform post-lokup checks.  Logs success/failure.
+ * This is used by the check, list and validate plugin methods.
+ *
+ * Returns true if allowed, false if denied, -1 on error and
+ * -2 for usage error.
+ */
+static int
+sudoers_check_common(struct sudoers_context *ctx, int pwflag)
+{
+    struct sudoers_match_info match_info = { NULL };
+    int oldlocale, ret = -1;
+    unsigned int validated;
+    time_t now;
+    debug_decl(sudoers_check_common, SUDOERS_DEBUG_PLUGIN);
+
+    /* If given the -P option, set the "preserve_groups" flag. */
+    if (ISSET(ctx->mode, MODE_PRESERVE_GROUPS))
+	def_preserve_groups = true;
+
+    /* Find command in path and apply per-command Defaults. */
+    cmnd_status = set_cmnd(ctx);
+    if (cmnd_status == NOT_FOUND_ERROR)
+	goto done;
+
+    /* Is root even allowed to run sudo? */
+    if (ctx->user.uid == 0 && !def_root_sudo) {
+	/* Not an audit event (should it be?). */
+	sudo_warnx("%s",
+	    U_("sudoers specifies that root is not allowed to sudo"));
+	ret = false;
+	goto done;
+    }
+
+    /* Check for -C overriding def_closefrom. */
+    if (ctx->user.closefrom >= 0 && ctx->user.closefrom != def_closefrom) {
+	if (!def_closefrom_override) {
+	    log_warningx(ctx, SLOG_NO_STDERR|SLOG_AUDIT,
+		N_("user not allowed to override closefrom limit"));
+	    sudo_warnx("%s", U_("you are not permitted to use the -C option"));
+	    goto bad;
+	}
+	def_closefrom = ctx->user.closefrom;
+    }
+
+    /*
+     * Check sudoers sources, using the locale specified in sudoers.
+     */
+    time(&now);
+    sudoers_setlocale(SUDOERS_LOCALE_SUDOERS, &oldlocale);
+    validated = sudoers_lookup(snl, ctx, now, cb_lookup, &match_info,
+	&cmnd_status, pwflag);
+    sudoers_setlocale(oldlocale, NULL);
+    if (ISSET(validated, VALIDATE_ERROR)) {
+	/* The lookup function should have printed an error. */
+	goto done;
+    }
+
+    if (match_info.us != NULL && match_info.us->file != NULL) {
+	free(ctx->source);
+	if (match_info.us->line != 0) {
+	    if (asprintf(&ctx->source, "%s:%d:%d", match_info.us->file,
+		    match_info.us->line, match_info.us->column) == -1)
+		ctx->source = NULL;
+	} else {
+	    ctx->source = strdup(match_info.us->file);
+	}
+	if (ctx->source == NULL) {
+	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	    goto done;
+	}
+    }
+
+    if (ctx->runas.cmnd == NULL) {
+	if ((ctx->runas.cmnd = strdup(ctx->user.cmnd)) == NULL) {
+	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	    goto done;
+	}
+    }
+
+    /* Defer uid/gid checks until after defaults have been updated. */
+    if (unknown_runas_uid && !def_runas_allow_unknown_id) {
+	log_warningx(ctx, SLOG_AUDIT, N_("unknown user %s"),
+	    ctx->runas.pw->pw_name);
+	goto done;
+    }
+    if (ctx->runas.gr != NULL) {
+	if (unknown_runas_gid && !def_runas_allow_unknown_id) {
+	    log_warningx(ctx, SLOG_AUDIT, N_("unknown group %s"),
+		ctx->runas.gr->gr_name);
+	    goto done;
+	}
+    }
+
+    /* If no command line args and "shell_noargs" is not set, error out. */
+    if (ISSET(ctx->mode, MODE_IMPLIED_SHELL) && !def_shell_noargs) {
+	/* Not an audit event. */
+	ret = -2; /* usage error */
+	goto done;
+    }
+
+    /* Bail if a tty is required and we don't have one. */
+    if (def_requiretty && !sudoers_tty_present(ctx)) {
+	log_warningx(ctx, SLOG_NO_STDERR|SLOG_AUDIT, N_("no tty"));
+	sudo_warnx("%s", U_("sorry, you must have a tty to run sudo"));
+	goto bad;
+    }
+
+    /* Check runas user's shell if running (or checking) a command. */
+    if (ISSET(ctx->mode, MODE_RUN|MODE_CHECK)) {
+	if (!user_shell_valid(ctx->runas.pw)) {
+	    log_warningx(ctx, SLOG_RAW_MSG|SLOG_AUDIT,
+		N_("invalid shell for user %s: %s"),
+		ctx->runas.pw->pw_name, ctx->runas.pw->pw_shell);
+	    goto bad;
+	}
+    }
+
+    /*
+     * We don't reset the environment for sudoedit or if the user
+     * specified the -E command line flag and they have setenv privs.
+     */
+    if (ISSET(ctx->mode, MODE_EDIT) ||
+	(ISSET(ctx->mode, MODE_PRESERVE_ENV) && def_setenv))
+	def_env_reset = false;
+
+    /* Build a new environment that avoids any nasty bits. */
+    if (!rebuild_env(ctx))
+	goto bad;
+
+    /* Require a password if sudoers says so.  */
+    switch (check_user(ctx, validated, ctx->mode)) {
+    case AUTH_SUCCESS:
+	/* user authenticated successfully. */
+	break;
+    case AUTH_FAILURE:
+	/* Note: log_denial() calls audit for us. */
+	if (!ISSET(validated, VALIDATE_SUCCESS)) {
+	    /* Only display a denial message if no password was read. */
+	    if (!log_denial(ctx, validated, def_passwd_tries <= 0))
+		goto done;
+	}
+	goto bad;
+    default:
+	/* some other error, ret is -1. */
+	goto done;
+    }
+
+    /* Check whether ctx->runas.chroot is permitted (if specified). */
+    switch (check_user_runchroot(ctx->runas.chroot)) {
+    case true:
+	break;
+    case false:
+	log_warningx(ctx, SLOG_NO_STDERR|SLOG_AUDIT,
+	    N_("user not allowed to change root directory to %s"),
+	    ctx->runas.chroot);
+	sudo_warnx(U_("you are not permitted to use the -R option with %s"),
+	    ctx->user.cmnd);
+	goto bad;
+    default:
+	goto done;
+    }
+
+    /* Check whether ctx->runas.cwd is permitted (if specified). */
+    switch (check_user_runcwd(ctx->runas.cwd)) {
+    case true:
+	break;
+    case false:
+	log_warningx(ctx, SLOG_NO_STDERR|SLOG_AUDIT,
+	    N_("user not allowed to change directory to %s"), ctx->runas.cwd);
+	sudo_warnx(U_("you are not permitted to use the -D option with %s"),
+	    ctx->user.cmnd);
+	goto bad;
+    default:
+	goto done;
+    }
+
+    /* If run as root with SUDO_USER set, set ctx->user.pw to that user. */
+    /* XXX - causes confusion when root is not listed in sudoers */
+    if (ISSET(ctx->mode, MODE_RUN|MODE_EDIT) && prev_user != NULL) {
+	if (ctx->user.uid == 0 && strcmp(prev_user, "root") != 0) {
+	    struct passwd *pw;
+
+	    if ((pw = sudo_getpwnam(prev_user)) != NULL) {
+		    if (ctx->user.pw != NULL)
+			sudo_pw_delref(ctx->user.pw);
+		    ctx->user.pw = pw;
+	    }
+	}
+    }
+
+    /* If the user was not allowed to run the command we are done. */
+    if (!ISSET(validated, VALIDATE_SUCCESS)) {
+	/* Note: log_failure() calls audit for us. */
+	if (!log_failure(ctx, validated, cmnd_status))
+	    goto done;
+	goto bad;
+    }
+
+    /*
+     * Check if the user is trying to run a setid binary in intercept mode.
+     * For the DSO intercept_type, we reject attempts to run setid binaries
+     * by default since the dynamic loader will clear LD_PRELOAD, defeating
+     * intercept.
+     */
+    if (def_intercept || ISSET(ctx->mode, MODE_POLICY_INTERCEPTED)) {
+	if (!def_intercept_allow_setid && ctx->user.cmnd_stat != NULL) {
+	    if (ISSET(ctx->user.cmnd_stat->st_mode, S_ISUID|S_ISGID)) {
+		CLR(validated, VALIDATE_SUCCESS);
+		if (!log_denial(ctx, validated|FLAG_INTERCEPT_SETID, true))
+		    goto done;
+		goto bad;
+	    }
+	}
+    }
+
+    /* Create Ubuntu-style dot file to indicate sudo was successful. */
+    if (create_admin_success_flag(ctx) == -1)
+	goto done;
+
+    /* Finally tell the user if the command did not exist. */
+    if (cmnd_status == NOT_FOUND_DOT) {
+	audit_failure(ctx, ctx->runas.argv, N_("command in current directory"));
+	sudo_warnx(U_("ignoring \"%s\" found in '.'\nUse \"sudo ./%s\" if this is the \"%s\" you wish to run."), ctx->user.cmnd, ctx->user.cmnd, ctx->user.cmnd);
+	goto bad;
+    } else if (cmnd_status == NOT_FOUND) {
+	if (ISSET(ctx->mode, MODE_CHECK)) {
+	    audit_failure(ctx, ctx->runas.argv, N_("%s: command not found"),
+		ctx->runas.argv[1]);
+	    sudo_warnx(U_("%s: command not found"), ctx->runas.argv[1]);
+	} else {
+	    audit_failure(ctx, ctx->runas.argv, N_("%s: command not found"),
+		ctx->user.cmnd);
+	    sudo_warnx(U_("%s: command not found"), ctx->user.cmnd);
+	    if (strncmp(ctx->user.cmnd, "cd", 2) == 0 && (ctx->user.cmnd[2] == '\0' ||
+		    isblank((unsigned char)ctx->user.cmnd[2]))) {
+		sudo_warnx("%s",
+		    U_("\"cd\" is a shell built-in command, it cannot be run directly."));
+		sudo_warnx("%s",
+		    U_("the -s option may be used to run a privileged shell."));
+		sudo_warnx("%s",
+		    U_("the -D option may be used to run a command in a specific directory."));
+	    }
+	}
+	goto bad;
+    }
+
+    /* If user specified a timeout make sure sudoers allows it. */
+    if (!def_user_command_timeouts && ctx->user.timeout > 0) {
+	log_warningx(ctx, SLOG_NO_STDERR|SLOG_AUDIT,
+	    N_("user not allowed to set a command timeout"));
+	sudo_warnx("%s",
+	    U_("sorry, you are not allowed set a command timeout"));
+	goto bad;
+    }
+
+    /* If user specified env vars make sure sudoers allows it. */
+    if (ISSET(ctx->mode, MODE_RUN) && !def_setenv) {
+	if (ISSET(ctx->mode, MODE_PRESERVE_ENV)) {
+	    log_warningx(ctx, SLOG_NO_STDERR|SLOG_AUDIT,
+		N_("user not allowed to preserve the environment"));
+	    sudo_warnx("%s",
+		U_("sorry, you are not allowed to preserve the environment"));
+	    goto bad;
+	} else {
+	    if (!validate_env_vars(ctx, ctx->user.env_add))
+		goto bad;
+	}
+    }
+
+    ret = true;
+    goto done;
+
+bad:
+    ret = false;
+done:
+    debug_return_int(ret);
+}
+
+static bool need_reinit;
+
+/*
+ * Check whether the user is allowed to run the specified command.
+ * Returns true if allowed, false if denied, -1 on error and
+ * -2 for usage error.
+ */
+int
+sudoers_check_cmnd(int argc, char * const argv[], char *env_add[],
+    void *closure)
+{
+    char *iolog_path = NULL;
+    mode_t cmnd_umask = ACCESSPERMS;
+    int ret = -1;
+    debug_decl(sudoers_check_cmnd, SUDOERS_DEBUG_PLUGIN);
+
+    sudo_warn_set_locale_func(sudoers_warn_setlocale);
+
+    if (argc == 0) {
+	sudo_warnx("%s", U_("no command specified"));
+	debug_return_int(-1);
+    }
+
+    if (need_reinit) {
+	/* Was previous command intercepted? */
+	if (ISSET(sudoers_ctx.mode, MODE_RUN) && def_intercept)
+	    SET(sudoers_ctx.mode, MODE_POLICY_INTERCEPTED);
+
+	/* Only certain mode flags are legal for intercepted commands. */
+	if (ISSET(sudoers_ctx.mode, MODE_POLICY_INTERCEPTED))
+	    sudoers_ctx.mode &= MODE_INTERCEPT_MASK;
+
+	/* Re-initialize defaults if we are called multiple times. */
+	if (!sudoers_reinit_defaults(&sudoers_ctx))
+	    debug_return_int(-1);
+    }
+    need_reinit = true;
+
+    unlimit_nproc();
+
+    if (!set_perms(&sudoers_ctx, PERM_INITIAL))
+	goto bad;
+
+    /* Environment variables specified on the command line. */
+    if (env_add != NULL && env_add[0] != NULL)
+	sudoers_ctx.user.env_add = env_add;
+
+    /*
+     * Make a local copy of argc/argv, with special handling for the
+     * '-i' option.  We also allocate an extra slot for bash's --login.
+     */
+    if (sudoers_ctx.runas.argv != NULL && sudoers_ctx.runas.argv != sudoers_ctx.runas.argv_saved) {
+	sudoers_gc_remove(GC_PTR, sudoers_ctx.runas.argv);
+	free(sudoers_ctx.runas.argv);
+    }
+    sudoers_ctx.runas.argv = reallocarray(NULL, (size_t)argc + 2, sizeof(char *));
+    if (sudoers_ctx.runas.argv == NULL) {
+	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	goto error;
+    }
+    sudoers_gc_add(GC_PTR, sudoers_ctx.runas.argv);
+    memcpy(sudoers_ctx.runas.argv, argv, (size_t)argc * sizeof(char *));
+    sudoers_ctx.runas.argc = argc;
+    sudoers_ctx.runas.argv[sudoers_ctx.runas.argc] = NULL;
+    if (ISSET(sudoers_ctx.mode, MODE_LOGIN_SHELL) && sudoers_ctx.runas.pw != NULL) {
+	sudoers_ctx.runas.argv[0] = strdup(sudoers_ctx.runas.pw->pw_shell);
+	if (sudoers_ctx.runas.argv[0] == NULL) {
+	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	    goto error;
+	}
+	sudoers_gc_add(GC_PTR, sudoers_ctx.runas.argv[0]);
+    }
+
+    ret = sudoers_check_common(&sudoers_ctx, 0);
+    if (ret != true)
+	goto done;
+
+    if (!remote_iologs) {
+	if (iolog_enabled && def_iolog_file && def_iolog_dir) {
+	    if ((iolog_path = format_iolog_path(&sudoers_ctx)) == NULL) {
+		if (!def_ignore_iolog_errors)
+		    goto error;
+		/* Unable to expand I/O log path, disable I/O logging. */
+		def_log_input = false;
+		def_log_output = false;
+		def_log_stdin = false;
+		def_log_stdout = false;
+		def_log_stderr = false;
+		def_log_ttyin = false;
+		def_log_ttyout = false;
+	    }
+	}
+    }
+
+    /*
+     * Set umask based on sudoers.
+     * If user's umask is more restrictive, OR in those bits too
+     * unless umask_override is set.
+     */
+    if (def_umask != ACCESSPERMS) {
+	cmnd_umask = def_umask;
+	if (!def_umask_override)
+	    cmnd_umask |= sudoers_ctx.user.umask;
+    }
+
+    if (ISSET(sudoers_ctx.mode, MODE_LOGIN_SHELL)) {
+	char *p;
+
+	/* Convert /bin/sh -> -sh so shell knows it is a login shell */
+	if ((p = strrchr(sudoers_ctx.runas.argv[0], '/')) == NULL)
+	    p = sudoers_ctx.runas.argv[0];
+	*p = '-';
+	sudoers_ctx.runas.argv[0] = p;
+
+	/*
+	 * Newer versions of bash require the --login option to be used
+	 * in conjunction with the -c option even if the shell name starts
+	 * with a '-'.  Unfortunately, bash 1.x uses -login, not --login
+	 * so this will cause an error for that.
+	 */
+	if (sudoers_ctx.runas.argc > 1 && strcmp(sudoers_ctx.runas.argv[0], "-bash") == 0 &&
+	    strcmp(sudoers_ctx.runas.argv[1], "-c") == 0) {
+	    /* We allocated extra space for the --login above. */
+	    memmove(&sudoers_ctx.runas.argv[2], &sudoers_ctx.runas.argv[1],
+		(size_t)sudoers_ctx.runas.argc * sizeof(char *));
+	    sudoers_ctx.runas.argv[1] = (char *)"--login";
+	    sudoers_ctx.runas.argc++;
+	}
+
+#ifdef _PATH_ENVIRONMENT
+	/* Insert system-wide environment variables. */
+	if (!read_env_file(&sudoers_ctx, _PATH_ENVIRONMENT, true, false))
+	    sudo_warn("%s", _PATH_ENVIRONMENT);
+#endif
+#ifdef HAVE_LOGIN_CAP_H
+	/* Set environment based on login class. */
+	if (sudoers_ctx.runas.class) {
+	    login_cap_t *lc = login_getclass(sudoers_ctx.runas.class);
+	    if (lc != NULL) {
+		setusercontext(lc, sudoers_ctx.runas.pw,
+		    sudoers_ctx.runas.pw->pw_uid, LOGIN_SETPATH|LOGIN_SETENV);
+		login_close(lc);
+	    }
+	}
+#endif /* HAVE_LOGIN_CAP_H */
+    }
+
+    /* Insert system-wide environment variables. */
+    if (def_restricted_env_file) {
+	if (!read_env_file(&sudoers_ctx, def_restricted_env_file, false, true))
+	    sudo_warn("%s", def_restricted_env_file);
+    }
+    if (def_env_file) {
+	if (!read_env_file(&sudoers_ctx, def_env_file, false, false))
+	    sudo_warn("%s", def_env_file);
+    }
+
+    /* Insert user-specified environment variables. */
+    if (!insert_env_vars(sudoers_ctx.user.env_add)) {
+	sudo_warnx("%s",
+	    U_("error setting user-specified environment variables"));
+	goto error;
+    }
+
+    /* Note: must call audit before uid change. */
+    if (ISSET(sudoers_ctx.mode, MODE_EDIT)) {
+	const char *env_editor = NULL;
+	char **edit_argv;
+	int edit_argc;
+
+	sudoers_ctx.sudoedit_nfiles = sudoers_ctx.runas.argc - 1;
+	free(sudoers_ctx.runas.cmnd);
+	sudoers_ctx.runas.cmnd = find_editor(sudoers_ctx.sudoedit_nfiles,
+	    sudoers_ctx.runas.argv + 1, &edit_argc, &edit_argv, NULL, &env_editor);
+	if (sudoers_ctx.runas.cmnd == NULL) {
+	    switch (errno) {
+	    case ENOENT:
+		audit_failure(&sudoers_ctx, sudoers_ctx.runas.argv,
+		    N_("%s: command not found"),
+		    env_editor ? env_editor : def_editor);
+		sudo_warnx(U_("%s: command not found"),
+		    env_editor ? env_editor : def_editor);
+		goto error;
+	    case EINVAL:
+		if (def_env_editor && env_editor != NULL) {
+		    /* User tried to do something funny with the editor. */
+		    log_warningx(&sudoers_ctx,
+			SLOG_NO_STDERR|SLOG_AUDIT|SLOG_SEND_MAIL,
+			"invalid user-specified editor: %s", env_editor);
+		    goto error;
+		}
+		FALLTHROUGH;
+	    default:
+		goto error;
+	    }
+	}
+	/* find_editor() already g/c'd edit_argv[] */
+	if (sudoers_ctx.runas.argv != sudoers_ctx.runas.argv_saved) {
+	    sudoers_gc_remove(GC_PTR, sudoers_ctx.runas.argv);
+	    free(sudoers_ctx.runas.argv);
+	}
+	sudoers_ctx.runas.argv = edit_argv;
+	sudoers_ctx.runas.argc = edit_argc;
+
+	/* We want to run the editor with the unmodified environment. */
+	env_swap_old();
+    }
+
+    /* Save the initial command and argv so we have it for exit logging. */
+    if (sudoers_ctx.runas.cmnd_saved == NULL) {
+	sudoers_ctx.runas.cmnd_saved = strdup(sudoers_ctx.runas.cmnd);
+	if (sudoers_ctx.runas.cmnd_saved == NULL) {
+	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	    goto error;
+	}
+	sudoers_ctx.runas.argv_saved = sudoers_ctx.runas.argv;
+    }
+
+    ret = true;
+    goto done;
+
+bad:
+    ret = false;
+    goto done;
+
+error:
+    ret = -1;
+
+done:
+    mail_parse_errors(&sudoers_ctx);
+
+    if (def_group_plugin)
+	group_plugin_unload();
+    reset_parser();
+
+    if (ret == -1) {
+	/* Free locally-allocated strings. */
+	free(iolog_path);
+    } else {
+	/* Store settings to pass back to front-end. */
+	if (!sudoers_policy_store_result(&sudoers_ctx, ret,
+	    sudoers_ctx.runas.argv, env_get(), cmnd_umask, iolog_path, closure))
+	    ret = -1;
+    }
+
+    /* Zero out stashed copy of environment, it is owned by the front-end. */
+    (void)env_init(NULL);
+
+    if (!rewind_perms())
+	ret = -1;
+
+    restore_nproc();
+
+    sudo_warn_set_locale_func(NULL);
+
+    debug_return_int(ret);
+}
+
+/*
+ * Validate the user and update their timestamp file entry.
+ * Returns true if allowed, false if denied, -1 on error and
+ * -2 for usage error.
+ */
+int
+sudoers_validate_user(void)
+{
+    int ret = -1;
+    debug_decl(sudoers_validate_user, SUDOERS_DEBUG_PLUGIN);
+
+    sudo_warn_set_locale_func(sudoers_warn_setlocale);
+
+    unlimit_nproc();
+
+    if (!set_perms(&sudoers_ctx, PERM_INITIAL))
+	goto done;
+
+    sudoers_ctx.runas.argv = reallocarray(NULL, 2, sizeof(char *));
+    if (sudoers_ctx.runas.argv == NULL) {
+	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	goto done;
+    }
+    sudoers_gc_add(GC_PTR, sudoers_ctx.runas.argv);
+    sudoers_ctx.runas.argv[0] = (char *)"validate";
+    sudoers_ctx.runas.argv[1] = NULL;
+    sudoers_ctx.runas.argc = 2;
+
+    ret = sudoers_check_common(&sudoers_ctx, I_VERIFYPW);
+
+done:
+    mail_parse_errors(&sudoers_ctx);
+
+    if (def_group_plugin)
+	group_plugin_unload();
+    reset_parser();
+    env_init(NULL);
+
+    if (!rewind_perms())
+	ret = -1;
+
+    restore_nproc();
+
+    sudo_warn_set_locale_func(NULL);
+
+    debug_return_int(ret);
+}
+
+/*
+ * List a user's privileges or check whether a specific command may be run.
+ * Returns true if allowed, false if denied, -1 on error and
+ * -2 for usage error.
+ */
+int
+sudoers_list(int argc, char * const argv[], const char *list_user, int verbose)
+{
+    struct passwd *pw;
+    int ret = -1;
+    debug_decl(sudoers_list, SUDOERS_DEBUG_PLUGIN);
+
+    sudo_warn_set_locale_func(sudoers_warn_setlocale);
+
+    unlimit_nproc();
+
+    if (!set_perms(&sudoers_ctx, PERM_INITIAL))
+	goto done;
+
+    if (list_user) {
+	if (sudoers_ctx.runas.list_pw != NULL)
+	    sudo_pw_delref(sudoers_ctx.runas.list_pw);
+	sudoers_ctx.runas.list_pw = sudo_getpwnam(list_user);
+	if (sudoers_ctx.runas.list_pw == NULL) {
+	    sudo_warnx(U_("unknown user %s"), list_user);
+	    goto done;
+	}
+    }
+
+    sudoers_ctx.runas.argv = reallocarray(NULL, (size_t)argc + 2, sizeof(char *));
+    if (sudoers_ctx.runas.argv == NULL) {
+	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	goto done;
+    }
+    sudoers_gc_add(GC_PTR, sudoers_ctx.runas.argv);
+    sudoers_ctx.runas.argv[0] = (char *)"list";
+    if (argc != 0)
+	memcpy(sudoers_ctx.runas.argv + 1, argv, (size_t)argc * sizeof(char *));
+    sudoers_ctx.runas.argc = argc + 1;
+    sudoers_ctx.runas.argv[sudoers_ctx.runas.argc] = NULL;
+
+    ret = sudoers_check_common(&sudoers_ctx, I_LISTPW);
+    if (ret != true)
+	goto done;
+
+    pw = sudoers_ctx.runas.list_pw ? sudoers_ctx.runas.list_pw : sudoers_ctx.user.pw;
+    if (ISSET(sudoers_ctx.mode, MODE_CHECK))
+	ret = display_cmnd(&sudoers_ctx, snl, pw, verbose);
+    else
+	ret = display_privs(&sudoers_ctx, snl, pw, verbose);
+
+done:
+    mail_parse_errors(&sudoers_ctx);
+
+    if (def_group_plugin)
+	group_plugin_unload();
+    reset_parser();
+    env_init(NULL);
+
+    if (!rewind_perms())
+	ret = -1;
+
+    restore_nproc();
+
+    sudo_warn_set_locale_func(NULL);
+
+    debug_return_int(ret);
+}
+
+/*
+ * Initialize timezone and fill in ctx->user.
+ */
+static bool
+init_vars(struct sudoers_context *ctx, char * const envp[])
+{
+    char * const * ep;
+    bool unknown_user = false;
+    debug_decl(init_vars, SUDOERS_DEBUG_PLUGIN);
+
+    if (!sudoers_initlocale(setlocale(LC_ALL, NULL), def_sudoers_locale)) {
+	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	debug_return_bool(false);
+    }
+
+#define MATCHES(s, v)	\
+    (strncmp((s), (v), sizeof(v) - 1) == 0 && (s)[sizeof(v) - 1] != '\0')
+
+    ctx->user.envp = envp;
+    for (ep = ctx->user.envp; *ep; ep++) {
+	switch (**ep) {
+	    case 'K':
+		if (MATCHES(*ep, "KRB5CCNAME="))
+		    ctx->user.ccname = *ep + sizeof("KRB5CCNAME=") - 1;
+		break;
+	    case 'P':
+		if (MATCHES(*ep, "PATH="))
+		    ctx->user.path = *ep + sizeof("PATH=") - 1;
+		break;
+	    case 'S':
+		if (MATCHES(*ep, "SUDO_PROMPT=")) {
+		    /* Don't override "sudo -p prompt" */
+		    if (ctx->user.prompt == NULL)
+			ctx->user.prompt = *ep + sizeof("SUDO_PROMPT=") - 1;
+		    break;
+		}
+		if (MATCHES(*ep, "SUDO_USER="))
+		    prev_user = *ep + sizeof("SUDO_USER=") - 1;
+		break;
+	    }
+    }
+#undef MATCHES
+
+    if (ctx->user.pw == NULL) {
+	/* Fake a struct passwd for the call to log_warningx(). */
+	ctx->user.pw = sudo_mkpwent(ctx->user.name, ctx->user.uid,
+	    ctx->user.gid, NULL, NULL);
+	unknown_user = true;
+    }
+    if (ctx->user.gid_list == NULL)
+	ctx->user.gid_list = sudo_get_gidlist(ctx->user.pw, ENTRY_TYPE_ANY);
+
+    /* Store initialize permissions so we can restore them later. */
+    if (!set_perms(ctx, PERM_INITIAL))
+	debug_return_bool(false);
+
+    /* Set parse callbacks */
+    set_callbacks();
+
+    /* It is now safe to use log_warningx() and set_perms() */
+    if (unknown_user) {
+	log_warningx(ctx, SLOG_SEND_MAIL, N_("unknown user %s"), ctx->user.name);
+	debug_return_bool(false);
+    }
+
+    /*
+     * Set runas passwd/group entries based on command line or sudoers.
+     * Note that if runas_group was specified without runas_user we
+     * run the command as the invoking user.
+     */
+    if (ctx->runas.group != NULL) {
+	if (!set_runasgr(ctx, ctx->runas.group, false))
+	    debug_return_bool(false);
+	if (!set_runaspw(ctx, ctx->runas.user ?
+		ctx->runas.user : ctx->user.name, false))
+	    debug_return_bool(false);
+    } else {
+	if (!set_runaspw(ctx, ctx->runas.user ?
+		ctx->runas.user : def_runas_default, false))
+	    debug_return_bool(false);
+    }
+
+    debug_return_bool(true);
+}
+
+/*
+ * Fill in ctx->user.cmnd and ctx->user.cmnd_stat variables.
+ * Does not fill in ctx->user.cmnd_base.
+ */
+int
+set_cmnd_path(struct sudoers_context *ctx, const char *runchroot)
+{
+    struct sudoers_pivot pivot_state = SUDOERS_PIVOT_INITIALIZER;
+    const char *cmnd_in;
+    char *cmnd_out = NULL;
+    char *path = ctx->user.path;
+    int ret;
+    debug_decl(set_cmnd_path, SUDOERS_DEBUG_PLUGIN);
+
+    cmnd_in = ISSET(ctx->mode, MODE_CHECK) ?
+	ctx->runas.argv[1] : ctx->runas.argv[0];
+
+    free(ctx->user.cmnd_list);
+    ctx->user.cmnd_list = NULL;
+    free(ctx->user.cmnd);
+    ctx->user.cmnd = NULL;
+    canon_path_free(ctx->user.cmnd_dir);
+    ctx->user.cmnd_dir = NULL;
+    if (def_secure_path && !user_is_exempt(ctx))
+	path = def_secure_path;
+
+    /* Pivot root. */
+    if (runchroot != NULL) {
+	if (!pivot_root(runchroot, &pivot_state))
+	    goto error;
+    }
+
+    ret = resolve_cmnd(ctx, cmnd_in, &cmnd_out, path);
+    if (ret == FOUND) {
+	char *slash = strrchr(cmnd_out, '/');
+	if (slash != NULL) {
+	    *slash = '\0';
+	    ctx->user.cmnd_dir = canon_path(cmnd_out);
+	    if (ctx->user.cmnd_dir == NULL && errno == ENOMEM)
+		goto error;
+	    *slash = '/';
+	}
+    }
+
+    if (ISSET(ctx->mode, MODE_CHECK))
+	ctx->user.cmnd_list = cmnd_out;
+    else
+	ctx->user.cmnd = cmnd_out;
+
+    /* Restore root. */
+    if (runchroot != NULL)
+	(void)unpivot_root(&pivot_state);
+
+    debug_return_int(ret);
+error:
+    if (runchroot != NULL)
+	(void)unpivot_root(&pivot_state);
+    free(cmnd_out);
+    debug_return_int(NOT_FOUND_ERROR);
+}
+
+/*
+ * Fill in ctx->user.cmnd, ctx->user.cmnd_stat and cmnd_status variables.
+ * Does not fill in ctx->user.cmnd_base.
+ */
+void
+set_cmnd_status(struct sudoers_context *ctx, const char *runchroot)
+{
+    cmnd_status = set_cmnd_path(ctx, runchroot);
+}
+
+/*
+ * Fill in ctx->user.cmnd, ctx->user.cmnd_args, ctx->user.cmnd_base and
+ * ctx->user.cmnd_stat variables and apply any command-specific defaults entries.
+ */
+static int
+set_cmnd(struct sudoers_context *ctx)
+{
+    struct sudo_nss *nss;
+    int ret = FOUND;
+    debug_decl(set_cmnd, SUDOERS_DEBUG_PLUGIN);
+
+    /* Allocate ctx->user.cmnd_stat for find_path() and match functions. */
+    free(ctx->user.cmnd_stat);
+    ctx->user.cmnd_stat = calloc(1, sizeof(struct stat));
+    if (ctx->user.cmnd_stat == NULL) {
+	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	debug_return_int(NOT_FOUND_ERROR);
+    }
+
+    /* Re-initialize for when we are called multiple times. */
+    free(ctx->runas.cmnd);
+    ctx->runas.cmnd = NULL;
+
+    if (ISSET(ctx->mode, MODE_RUN|MODE_EDIT|MODE_CHECK)) {
+	if (!ISSET(ctx->mode, MODE_EDIT)) {
+	    const char *runchroot = ctx->runas.chroot;
+	    if (runchroot == NULL && def_runchroot != NULL &&
+		    strcmp(def_runchroot, "*") != 0)
+		runchroot = def_runchroot;
+
+	    ret = set_cmnd_path(ctx, runchroot);
+	    if (ret == NOT_FOUND_ERROR) {
+		if (errno == ENAMETOOLONG) {
+		    audit_failure(ctx, ctx->runas.argv, N_("command too long"));
+		}
+		log_warning(ctx, 0, "%s", ctx->runas.argv[0]);
+		debug_return_int(ret);
+	    }
+	}
+
+	/* set ctx->user.cmnd_args */
+	free(ctx->user.cmnd_args);
+	ctx->user.cmnd_args = NULL;
+	if (ISSET(ctx->mode, MODE_CHECK)) {
+	    if (ctx->runas.argc > 2) {
+		/* Skip the command being listed in ctx->runas.argv[1]. */
+		ctx->user.cmnd_args = strvec_join(ctx->runas.argv + 2, ' ', NULL);
+		if (ctx->user.cmnd_args == NULL)
+		    debug_return_int(NOT_FOUND_ERROR);
+	    }
+	} else if (ctx->runas.argc > 1) {
+	    if (ISSET(ctx->mode, MODE_SHELL|MODE_LOGIN_SHELL) &&
+		    ISSET(ctx->mode, MODE_RUN)) {
+		/*
+		 * When running a command via a shell, the sudo front-end
+		 * escapes potential meta chars.  We unescape non-spaces
+		 * for sudoers matching and logging purposes.
+		 * TODO: move escaping to the policy plugin instead
+		 */
+		ctx->user.cmnd_args = strvec_join(ctx->runas.argv + 1, ' ',
+		    strlcpy_unescape);
+	    } else {
+		ctx->user.cmnd_args = strvec_join(ctx->runas.argv + 1, ' ',
+		    NULL);
+	    }
+	    if (ctx->user.cmnd_args == NULL)
+		debug_return_int(NOT_FOUND_ERROR);
+	}
+    }
+    if (ctx->user.cmnd == NULL) {
+	ctx->user.cmnd = strdup(ctx->runas.argv[0]);
+	if (ctx->user.cmnd == NULL)
+	    debug_return_int(NOT_FOUND_ERROR);
+    }
+    ctx->user.cmnd_base = sudo_basename(ctx->user.cmnd);
+
+    /* Convert "sudo sudoedit" -> "sudoedit" */
+    if (ISSET(ctx->mode, MODE_RUN) && strcmp(ctx->user.cmnd_base, "sudoedit") == 0) {
+	char *new_cmnd;
+
+	CLR(ctx->mode, MODE_RUN);
+	SET(ctx->mode, MODE_EDIT);
+	sudo_warnx("%s", U_("sudoedit doesn't need to be run via sudo"));
+	if ((new_cmnd = strdup("sudoedit")) == NULL) {
+	    sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+	    debug_return_int(NOT_FOUND_ERROR);
+	}
+	free(ctx->user.cmnd);
+	ctx->user.cmnd_base = ctx->user.cmnd = new_cmnd;
+    }
+
+    TAILQ_FOREACH(nss, snl, entries) {
+	/* Missing/invalid defaults is not a fatal error. */
+	(void)update_defaults(ctx, nss->parse_tree, NULL, SETDEF_CMND, false);
+    }
+
+    debug_return_int(ret);
+}
+
+static int
+open_file(const char *path, int flags)
+{
+    int fd;
+    debug_decl(open_file, SUDOERS_DEBUG_PLUGIN);
+
+    if (!set_perms(NULL, PERM_SUDOERS))
+	debug_return_int(-1);
+
+    fd = open(path, flags);
+    if (fd == -1 && errno == EACCES && geteuid() != ROOT_UID) {
+	/*
+	 * If we tried to open sudoers as non-root but got EACCES,
+	 * try again as root.
+	 */
+	int serrno = errno;
+	if (restore_perms() && set_perms(NULL, PERM_ROOT))
+	    fd = open(path, flags);
+	errno = serrno;
+    }
+    if (!restore_perms()) {
+	/* unable to change back to root */
+	if (fd != -1) {
+	    close(fd);
+	    fd = -1;
+	}
+    }
+
+    debug_return_int(fd);
+}
+
+/*
+ * Open sudoers file and check mode/owner/type.
+ * Returns a handle to the sudoers file or NULL on error.
+ */
+FILE *
+open_sudoers(const char *path, char **outfile, bool doedit, bool *keepopen)
+{
+    char fname[PATH_MAX];
+    FILE *fp = NULL;
+    struct stat sb;
+    int error, fd;
+    debug_decl(open_sudoers, SUDOERS_DEBUG_PLUGIN);
+
+    fd = sudo_open_conf_path(path, fname, sizeof(fname), open_file);
+    if (sudoers_ctx.parser_conf.ignore_perms) {
+	/* Skip sudoers security checks when ignore_perms is set. */
+	if (fd == -1 || fstat(fd, &sb) == -1)
+	    error = SUDO_PATH_MISSING;
+	else
+	    error = SUDO_PATH_SECURE;
+    } else {
+	error = sudo_secure_fd(fd, S_IFREG, sudoers_file_uid(),
+	    sudoers_file_gid(), &sb);
+    }
+    switch (error) {
+    case SUDO_PATH_SECURE:
+	/*
+	 * Make sure we can read the file so we can present the
+	 * user with a reasonable error message (unlike the lexer).
+	 */
+	if ((fp = fdopen(fd, "r")) == NULL) {
+	    log_warning(&sudoers_ctx, SLOG_PARSE_ERROR,
+		N_("unable to open %s"), fname);
+	} else {
+	    fd = -1;
+	    if (sb.st_size != 0 && fgetc(fp) == EOF) {
+		log_warning(&sudoers_ctx, SLOG_PARSE_ERROR,
+		    N_("unable to read %s"), fname);
+		fclose(fp);
+		fp = NULL;
+	    } else {
+		/* Rewind fp and set close on exec flag. */
+		rewind(fp);
+		(void)fcntl(fileno(fp), F_SETFD, 1);
+		if (outfile != NULL) {
+                    *outfile = sudo_rcstr_dup(fname);
+		    if (*outfile == NULL) {
+			sudo_warnx(U_("%s: %s"), __func__,
+			    U_("unable to allocate memory"));
+			fclose(fp);
+			fp = NULL;
+		    }
+		}
+	    }
+	}
+	break;
+    case SUDO_PATH_MISSING:
+	log_warning(&sudoers_ctx, SLOG_PARSE_ERROR,
+	    N_("unable to open %s"), path);
+	break;
+    case SUDO_PATH_BAD_TYPE:
+	log_warningx(&sudoers_ctx, SLOG_PARSE_ERROR,
+	    N_("%s is not a regular file"), fname);
+	break;
+    case SUDO_PATH_WRONG_OWNER:
+	log_warningx(&sudoers_ctx, SLOG_PARSE_ERROR,
+	    N_("%s is owned by uid %u, should be %u"), fname,
+	    (unsigned int)sb.st_uid, (unsigned int)sudoers_file_uid());
+	break;
+    case SUDO_PATH_WORLD_WRITABLE:
+	log_warningx(&sudoers_ctx, SLOG_PARSE_ERROR,
+	    N_("%s is world writable"), fname);
+	break;
+    case SUDO_PATH_GROUP_WRITABLE:
+	log_warningx(&sudoers_ctx, SLOG_PARSE_ERROR,
+	    N_("%s is owned by gid %u, should be %u"), fname,
+	    (unsigned int)sb.st_gid, (unsigned int)sudoers_file_gid());
+	break;
+    default:
+	sudo_warnx("%s: internal error, unexpected error %d", __func__, error);
+	break;
+    }
+
+    if (fp == NULL && fd != -1)
+	close(fd);
+
+    debug_return_ptr(fp);
+}
+
+#ifdef HAVE_LOGIN_CAP_H
+static bool
+set_loginclass(struct sudoers_context *ctx)
+{
+    const struct passwd *pw = ctx->runas.pw ? ctx->runas.pw : ctx->user.pw;
+    const unsigned int errflags = SLOG_RAW_MSG;
+    login_cap_t *lc;
+    bool ret = true;
+    debug_decl(set_loginclass, SUDOERS_DEBUG_PLUGIN);
+
+    if (!def_use_loginclass)
+	goto done;
+
+    if (ctx->runas.class && strcmp(ctx->runas.class, "-") != 0) {
+	if (ctx->user.uid != 0 && pw->pw_uid != 0) {
+	    sudo_warnx(U_("only root can use \"-c %s\""), ctx->runas.class);
+	    ret = false;
+	    goto done;
+	}
+    } else {
+	ctx->runas.class = pw->pw_class;
+	if (!ctx->runas.class || !*ctx->runas.class)
+	    ctx->runas.class = (char *)
+		((pw->pw_uid == 0) ? LOGIN_DEFROOTCLASS : LOGIN_DEFCLASS);
+    }
+
+    /* Make sure specified login class is valid. */
+    lc = login_getclass(ctx->runas.class);
+    if (!lc || !lc->lc_class || strcmp(lc->lc_class, ctx->runas.class) != 0) {
+	/*
+	 * Don't make it an error if the user didn't specify the login
+	 * class themselves.  We do this because if login.conf gets
+	 * corrupted we want the admin to be able to use sudo to fix it.
+	 */
+	log_warningx(ctx, errflags, N_("unknown login class %s"),
+	    ctx->runas.class);
+	def_use_loginclass = false;
+	if (ctx->runas.class)
+	    ret = false;
+    }
+    login_close(lc);
+done:
+    debug_return_bool(ret);
+}
+#else
+static bool
+set_loginclass(struct sudoers_context *ctx)
+{
+    return true;
+}
+#endif /* HAVE_LOGIN_CAP_H */
+
+/*
+ * Get passwd entry for the user we are going to run commands as
+ * and store it in ctx->runas.pw.  By default, commands run as "root".
+ */
+static bool
+set_runaspw(struct sudoers_context *ctx, const char *user, bool quiet)
+{
+    struct passwd *pw = NULL;
+    debug_decl(set_runaspw, SUDOERS_DEBUG_PLUGIN);
+
+    unknown_runas_uid = false;
+    if (*user == '#') {
+	const char *errstr;
+	uid_t uid = sudo_strtoid(user + 1, &errstr);
+	if (errstr == NULL) {
+	    if ((pw = sudo_getpwuid(uid)) == NULL) {
+		unknown_runas_uid = true;
+		pw = sudo_fakepwnam(user, ctx->user.gid);
+	    }
+	}
+    }
+    if (pw == NULL) {
+	if ((pw = sudo_getpwnam(user)) == NULL) {
+	    if (!quiet)
+		log_warningx(ctx, SLOG_AUDIT, N_("unknown user %s"), user);
+	    debug_return_bool(false);
+	}
+    }
+    if (ctx->runas.pw != NULL)
+	sudo_pw_delref(ctx->runas.pw);
+    ctx->runas.pw = pw;
+    debug_return_bool(true);
+}
+
+/*
+ * Get group entry for the group we are going to run commands as
+ * and store it in ctx->runas.gr.
+ */
+static bool
+set_runasgr(struct sudoers_context *ctx, const char *group, bool quiet)
+{
+    struct group *gr = NULL;
+    debug_decl(set_runasgr, SUDOERS_DEBUG_PLUGIN);
+
+    unknown_runas_gid = false;
+    if (*group == '#') {
+	const char *errstr;
+	gid_t gid = sudo_strtoid(group + 1, &errstr);
+	if (errstr == NULL) {
+	    if ((gr = sudo_getgrgid(gid)) == NULL) {
+		unknown_runas_gid = true;
+		gr = sudo_fakegrnam(group);
+	    }
+	}
+    }
+    if (gr == NULL) {
+	if ((gr = sudo_getgrnam(group)) == NULL) {
+	    if (!quiet)
+		log_warningx(ctx, SLOG_AUDIT, N_("unknown group %s"), group);
+	    debug_return_bool(false);
+	}
+    }
+    if (ctx->runas.gr != NULL)
+	sudo_gr_delref(ctx->runas.gr);
+    ctx->runas.gr = gr;
+    debug_return_bool(true);
+}
+
+/*
+ * Callback for runas_default sudoers setting.
+ */
+bool
+cb_runas_default(struct sudoers_context *ctx, const char *file, int line,
+    int column, const union sudo_defs_val *sd_un, int op)
+{
+    debug_decl(cb_runas_default, SUDOERS_DEBUG_PLUGIN);
+
+    /* Only reset runaspw if user didn't specify one. */
+    if (ctx->runas.user == NULL && ctx->runas.group == NULL)
+	debug_return_bool(set_runaspw(ctx, sd_un->str, true));
+    debug_return_bool(true);
+}
+
+/*
+ * Cleanup hook for sudo_fatal()/sudo_fatalx()
+ * Also called at policy close time.
+ */
+void
+sudoers_cleanup(void)
+{
+    struct sudo_nss *nss;
+    struct defaults *def;
+    debug_decl(sudoers_cleanup, SUDOERS_DEBUG_PLUGIN);
+
+    if (snl != NULL) {
+	TAILQ_FOREACH(nss, snl, entries) {
+	    nss->close(&sudoers_ctx, nss);
+	}
+	snl = NULL;
+	reset_parser();
+    }
+    while ((def = TAILQ_FIRST(&initial_defaults)) != NULL) {
+	TAILQ_REMOVE(&initial_defaults, def, entries);
+	free(def->var);
+	free(def->val);
+	free(def);
+    }
+    need_reinit = false;
+    if (def_group_plugin)
+	group_plugin_unload();
+    sudoers_ctx_free(&sudoers_ctx);
+    sudo_freepwcache();
+    sudo_freegrcache();
+    canon_path_free_cache();
+
+    /* We must free the cached environment before running g/c. */
+    env_free();
+
+    /* Run garbage collector. */
+    sudoers_gc_run();
+
+    /* Clear globals */
+    prev_user = NULL;
+
+    debug_return;
+}
+
+bool
+sudoers_set_mode(unsigned int flags, unsigned int mask)
+{
+    SET(sudoers_ctx.mode, flags);
+    return ((sudoers_ctx.mode & mask) == sudoers_ctx.mode);
+}
+
+const struct sudoers_context *
+sudoers_get_context(void)
+{
+    return &sudoers_ctx;
+}