diff options
Diffstat (limited to 'plugins/sudoers/sudoers.c')
| -rw-r--r-- | plugins/sudoers/sudoers.c | 1556 |
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; +} |