/* * Copyright (c) 1993-1996, 1998-2009 Todd C. Miller * * 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. * * For a brief history of sudo, please see the HISTORY file included * with this distribution. */ #define _SUDO_MAIN #ifdef __TANDEM # include #endif #include #include #include #include #include #ifdef HAVE_SETRLIMIT # include # include #endif #include #ifdef STDC_HEADERS # include # include #else # ifdef HAVE_STDLIB_H # include # endif #endif /* STDC_HEADERS */ #ifdef HAVE_STRING_H # if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS) # include # endif # include #else # ifdef HAVE_STRINGS_H # include # endif #endif /* HAVE_STRING_H */ #ifdef HAVE_UNISTD_H # include #endif /* HAVE_UNISTD_H */ #include #include #include #include #include #if TIME_WITH_SYS_TIME # include #endif #ifdef HAVE_SETLOCALE # include #endif #include #include #if defined(HAVE_GETPRPWNAM) && defined(HAVE_SET_AUTH_PARAMETERS) # ifdef __hpux # undef MAXINT # include # else # include # endif /* __hpux */ # include #endif /* HAVE_GETPRPWNAM && HAVE_SET_AUTH_PARAMETERS */ #ifdef HAVE_LOGIN_CAP_H # include # ifndef LOGIN_DEFROOTCLASS # define LOGIN_DEFROOTCLASS "daemon" # endif #endif #ifdef HAVE_PROJECT_H # include # include #endif #ifdef HAVE_SELINUX # include #endif #include #include "sudo.h" #include "lbuf.h" #include "interfaces.h" #ifdef USING_NONUNIX_GROUPS # include "nonunix.h" #endif /* * Prototypes */ static void init_vars __P((int, char **)); static int set_cmnd __P((int)); static int parse_args __P((int, char **)); static void initial_setup __P((void)); static void set_loginclass __P((struct passwd *)); static void set_project __P((struct passwd *)); static void set_runasgr __P((char *)); static void set_runaspw __P((char *)); static void show_version __P((void)); static void usage __P((int)) __attribute__((__noreturn__)); static void usage_excl __P((int)) __attribute__((__noreturn__)); static struct passwd *get_authpw __P((void)); extern int sudo_edit __P((int, char **, char **)); extern void rebuild_env __P((int, int)); void validate_env_vars __P((struct list_member *)); void insert_env_vars __P((struct list_member *)); /* * Globals */ int Argc, NewArgc; char **Argv, **NewArgv; char *prev_user; static int user_closefrom = -1; struct sudo_user sudo_user; struct passwd *auth_pw, *list_pw; struct interface *interfaces; int num_interfaces; int tgetpass_flags; int long_list; uid_t timestamp_uid; extern int errorlineno; extern int parse_error; extern char *errorfile; #if defined(RLIMIT_CORE) && !defined(SUDO_DEVEL) static struct rlimit corelimit; #endif /* RLIMIT_CORE && !SUDO_DEVEL */ #ifdef HAVE_LOGIN_CAP_H login_cap_t *lc; #endif /* HAVE_LOGIN_CAP_H */ #ifdef HAVE_BSD_AUTH_H char *login_style; #endif /* HAVE_BSD_AUTH_H */ sigaction_t saved_sa_int, saved_sa_quit, saved_sa_tstp; static char *runas_user; static char *runas_group; static struct sudo_nss_list *snl; /* For getopt(3) */ extern char *optarg; extern int optind; int main(argc, argv, envp) int argc; char **argv; char **envp; { int sources = 0, validated; int fd, cmnd_status, sudo_mode, pwflag, rc = 0; sigaction_t sa; struct sudo_nss *nss; #if defined(SUDO_DEVEL) && defined(__OpenBSD__) extern char *malloc_options; malloc_options = "AFGJPR"; #endif #ifdef HAVE_SETLOCALE setlocale(LC_ALL, ""); #endif Argv = argv; if ((Argc = argc) < 1) usage(1); /* Must be done as the first thing... */ #if defined(HAVE_GETPRPWNAM) && defined(HAVE_SET_AUTH_PARAMETERS) (void) set_auth_parameters(Argc, Argv); # ifdef HAVE_INITPRIVS initprivs(); # endif #endif /* HAVE_GETPRPWNAM && HAVE_SET_AUTH_PARAMETERS */ if (geteuid() != 0) errorx(1, "must be setuid root"); /* * Signal setup: * Ignore keyboard-generated signals so the user cannot interrupt * us at some point and avoid the logging. * Install handler to wait for children when they exit. */ zero_bytes(&sa, sizeof(sa)); sigemptyset(&sa.sa_mask); sa.sa_flags = SA_RESTART; sa.sa_handler = SIG_IGN; (void) sigaction(SIGINT, &sa, &saved_sa_int); (void) sigaction(SIGQUIT, &sa, &saved_sa_quit); (void) sigaction(SIGTSTP, &sa, &saved_sa_tstp); /* * Turn off core dumps and make sure fds 0-2 are open. */ initial_setup(); sudo_setpwent(); sudo_setgrent(); /* Parse our arguments. */ sudo_mode = parse_args(Argc, Argv); /* Setup defaults data structures. */ init_defaults(); /* Load the list of local ip addresses and netmasks. */ load_interfaces(); pwflag = 0; if (ISSET(sudo_mode, MODE_SHELL)) user_cmnd = "shell"; else if (ISSET(sudo_mode, MODE_EDIT)) user_cmnd = "sudoedit"; else { switch (sudo_mode) { case MODE_VERSION: show_version(); break; case MODE_HELP: usage(0); break; case MODE_VALIDATE: case MODE_VALIDATE|MODE_INVALIDATE: user_cmnd = "validate"; pwflag = I_VERIFYPW; break; case MODE_KILL: case MODE_INVALIDATE: user_cmnd = "kill"; pwflag = -1; break; case MODE_LISTDEFS: list_options(); exit(0); break; case MODE_LIST: case MODE_LIST|MODE_INVALIDATE: user_cmnd = "list"; pwflag = I_LISTPW; break; case MODE_CHECK: case MODE_CHECK|MODE_INVALIDATE: pwflag = I_LISTPW; break; } } /* Must have a command to run... */ if (user_cmnd == NULL && NewArgc == 0) usage(1); init_vars(sudo_mode, envp); /* XXX - move this later? */ #ifdef USING_NONUNIX_GROUPS sudo_nonunix_groupcheck_init(); /* initialise nonunix groups impl */ #endif /* USING_NONUNIX_GROUPS */ /* Parse nsswitch.conf for sudoers order. */ snl = sudo_read_nss(); /* Open and parse sudoers, set global defaults */ tq_foreach_fwd(snl, nss) { if (nss->open(nss) == 0 && nss->parse(nss) == 0) { sources++; nss->setdefs(nss); } } if (sources == 0) log_error(0, "no valid sudoers sources found, quitting"); /* XXX - collect post-sudoers parse settings into a function */ /* * Set runas passwd/group entries based on command line or sudoers. * Note that if runas_group was specified without runas_user we * defer setting runas_pw so the match routines know to ignore it. */ if (runas_group != NULL) { set_runasgr(runas_group); if (runas_user != NULL) set_runaspw(runas_user); } else set_runaspw(runas_user ? runas_user : def_runas_default); if (!update_defaults(SETDEF_RUNAS)) log_error(NO_STDERR|NO_EXIT, "problem with defaults entries"); /* Set login class if applicable. */ set_loginclass(sudo_user.pw); /* Update initial shell now that runas is set. */ if (ISSET(sudo_mode, MODE_LOGIN_SHELL)) NewArgv[0] = runas_pw->pw_shell; /* This goes after sudoers is parsed since it may have timestamp options. */ if (sudo_mode == MODE_KILL || sudo_mode == MODE_INVALIDATE) { remove_timestamp((sudo_mode == MODE_KILL)); cleanup(0); exit(0); } /* Is root even allowed to run sudo? */ if (user_uid == 0 && !def_root_sudo) { (void) fprintf(stderr, "Sorry, %s has been configured to not allow root to run it.\n", getprogname()); exit(1); } /* Check for -C overriding def_closefrom. */ if (user_closefrom >= 0 && user_closefrom != def_closefrom) { if (!def_closefrom_override) errorx(1, "you are not permitted to use the -C option"); else def_closefrom = user_closefrom; } cmnd_status = set_cmnd(sudo_mode); #ifdef HAVE_SETLOCALE if (!setlocale(LC_ALL, def_sudoers_locale)) { warningx("unable to set locale to \"%s\", using \"C\"", def_sudoers_locale); setlocale(LC_ALL, "C"); } #endif validated = FLAG_NO_USER | FLAG_NO_HOST; tq_foreach_fwd(snl, nss) { validated = nss->lookup(nss, validated, pwflag); if (ISSET(validated, VALIDATE_OK)) { /* Handle "= auth" in netsvc.conf */ if (nss->ret_if_found) break; } else { /* Handle [NOTFOUND=return] */ if (nss->ret_if_notfound) break; } } if (safe_cmnd == NULL) safe_cmnd = estrdup(user_cmnd); #ifdef HAVE_SETLOCALE setlocale(LC_ALL, ""); #endif /* If only a group was specified, set runas_pw based on invoking user. */ if (runas_pw == NULL) set_runaspw(user_name); /* * Look up the timestamp dir owner if one is specified. */ if (def_timestampowner) { struct passwd *pw; if (*def_timestampowner == '#') pw = sudo_getpwuid(atoi(def_timestampowner + 1)); else pw = sudo_getpwnam(def_timestampowner); if (!pw) log_error(0, "timestamp owner (%s): No such user", def_timestampowner); timestamp_uid = pw->pw_uid; } /* If given the -P option, set the "preserve_groups" flag. */ if (ISSET(sudo_mode, MODE_PRESERVE_GROUPS)) def_preserve_groups = TRUE; /* If no command line args and "set_home" is not set, error out. */ if (ISSET(sudo_mode, MODE_IMPLIED_SHELL) && !def_shell_noargs) usage(1); /* Bail if a tty is required and we don't have one. */ if (def_requiretty) { if ((fd = open(_PATH_TTY, O_RDWR|O_NOCTTY)) == -1) { audit_failure(NewArgv, "no tty"); log_error(NO_MAIL, "sorry, you must have a tty to run sudo"); } else (void) close(fd); } /* Use askpass value from sudoers unless user specified their own. */ if (def_askpass && !user_askpass) user_askpass = def_askpass; /* User may have overridden environment resetting via the -E flag. */ if (ISSET(sudo_mode, MODE_PRESERVE_ENV) && def_setenv) def_env_reset = FALSE; /* Build a new environment that avoids any nasty bits. */ rebuild_env(sudo_mode, def_noexec); /* Fill in passwd struct based on user we are authenticating as. */ auth_pw = get_authpw(); /* Require a password if sudoers says so. */ if (def_authenticate) check_user(validated, sudo_mode); /* If run as root with SUDO_USER set, set sudo_user.pw to that user. */ /* XXX - causes confusion when root is not listed in sudoers */ if (sudo_mode & (MODE_RUN | MODE_EDIT) && prev_user != NULL) { if (user_uid == 0 && strcmp(prev_user, "root") != 0) { struct passwd *pw; if ((pw = sudo_getpwnam(prev_user)) != NULL) sudo_user.pw = pw; } } if (ISSET(validated, VALIDATE_OK)) { /* Finally tell the user if the command did not exist. */ if (cmnd_status == NOT_FOUND_DOT) { audit_failure(NewArgv, "command in current directory"); errorx(1, "ignoring `%s' found in '.'\nUse `sudo ./%s' if this is the `%s' you wish to run.", user_cmnd, user_cmnd, user_cmnd); } else if (cmnd_status == NOT_FOUND) { audit_failure(NewArgv, "%s: command not found", user_cmnd); errorx(1, "%s: command not found", user_cmnd); } /* If user specified env vars make sure sudoers allows it. */ if (ISSET(sudo_mode, MODE_RUN) && !def_setenv) { if (ISSET(sudo_mode, MODE_PRESERVE_ENV)) log_error(NO_MAIL, "sorry, you are not allowed to preserve the environment"); else validate_env_vars(sudo_user.env_vars); } log_allowed(validated); if (ISSET(sudo_mode, MODE_CHECK)) rc = display_cmnd(snl, list_pw ? list_pw : sudo_user.pw); else if (ISSET(sudo_mode, MODE_LIST)) display_privs(snl, list_pw ? list_pw : sudo_user.pw); /* Cleanup sudoers sources */ tq_foreach_fwd(snl, nss) nss->close(nss); #ifdef USING_NONUNIX_GROUPS /* Finished with the groupcheck code */ sudo_nonunix_groupcheck_cleanup(); #endif /* Deferred exit due to sudo_ldap_close() */ if (ISSET(sudo_mode, (MODE_VALIDATE|MODE_CHECK|MODE_LIST))) exit(rc); /* * 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 != 0777) { if (def_umask_override) { umask(def_umask); } else { mode_t mask = umask(def_umask); mask |= def_umask; if (mask != def_umask) umask(mask); } } /* Restore coredumpsize resource limit. */ #if defined(RLIMIT_CORE) && !defined(SUDO_DEVEL) (void) setrlimit(RLIMIT_CORE, &corelimit); #endif /* RLIMIT_CORE && !SUDO_DEVEL */ /* Must audit before uid change. */ audit_success(NewArgv); /* Become specified user or root if executing a command. */ if (ISSET(sudo_mode, MODE_RUN)) set_perms(PERM_FULL_RUNAS); if (ISSET(sudo_mode, MODE_LOGIN_SHELL)) { char *p; /* Convert /bin/sh -> -sh so shell knows it is a login shell */ if ((p = strrchr(NewArgv[0], '/')) == NULL) p = NewArgv[0]; *p = '-'; NewArgv[0] = p; /* Change to target user's homedir. */ if (chdir(runas_pw->pw_dir) == -1) warning("unable to change directory to %s", runas_pw->pw_dir); #if defined(__linux__) || defined(_AIX) /* Insert system-wide environment variables. */ read_env_file(_PATH_ENVIRONMENT, TRUE); #endif } if (ISSET(sudo_mode, MODE_EDIT)) exit(sudo_edit(NewArgc, NewArgv, envp)); /* Insert system-wide environment variables. */ if (def_env_file) read_env_file(def_env_file, FALSE); /* Insert user-specified environment variables. */ insert_env_vars(sudo_user.env_vars); /* Restore signal handlers before we exec. */ (void) sigaction(SIGINT, &saved_sa_int, NULL); (void) sigaction(SIGQUIT, &saved_sa_quit, NULL); (void) sigaction(SIGTSTP, &saved_sa_tstp, NULL); /* Close the password and group files and free up memory. */ sudo_endpwent(); sudo_endgrent(); closefrom(def_closefrom); #ifndef PROFILING if (ISSET(sudo_mode, MODE_BACKGROUND) && fork() > 0) { syslog(LOG_AUTH|LOG_ERR, "fork"); exit(0); } else { #ifdef HAVE_SELINUX if (is_selinux_enabled() > 0 && user_role != NULL) selinux_exec(user_role, user_type, NewArgv, ISSET(sudo_mode, MODE_LOGIN_SHELL)); #endif execv(safe_cmnd, NewArgv); } #else exit(0); #endif /* PROFILING */ /* * If we got here then execve() failed... */ if (errno == ENOEXEC) { NewArgv--; /* at least one extra slot... */ NewArgv[0] = "sh"; NewArgv[1] = safe_cmnd; execv(_PATH_BSHELL, NewArgv); } warning("unable to execute %s", safe_cmnd); exit(127); } else if (ISSET(validated, FLAG_NO_USER | FLAG_NO_HOST)) { audit_failure(NewArgv, "No user or host"); log_denial(validated, 1); exit(1); } else { if (def_path_info) { /* * We'd like to not leak path info at all here, but that can * *really* confuse the users. To really close the leak we'd * have to say "not allowed to run foo" even when the problem * is just "no foo in path" since the user can trivially set * their path to just contain a single dir. */ log_denial(validated, !(cmnd_status == NOT_FOUND_DOT || cmnd_status == NOT_FOUND)); if (cmnd_status == NOT_FOUND) warningx("%s: command not found", user_cmnd); else if (cmnd_status == NOT_FOUND_DOT) warningx("ignoring `%s' found in '.'\nUse `sudo ./%s' if this is the `%s' you wish to run.", user_cmnd, user_cmnd, user_cmnd); } else { /* Just tell the user they are not allowed to run foo. */ log_denial(validated, 1); } audit_failure(NewArgv, "validation failure"); exit(1); } exit(0); /* not reached */ } /* * Initialize timezone, set umask, fill in ``sudo_user'' struct and * load the ``interfaces'' array. */ static void init_vars(sudo_mode, envp) int sudo_mode; char **envp; { char *p, **ep, thost[MAXHOSTNAMELEN + 1]; int nohostname; /* Sanity check command from user. */ if (user_cmnd == NULL && strlen(NewArgv[0]) >= PATH_MAX) errorx(1, "%s: File name too long", NewArgv[0]); #ifdef HAVE_TZSET (void) tzset(); /* set the timezone if applicable */ #endif /* HAVE_TZSET */ /* Default value for cmnd and cwd, overridden later. */ if (user_cmnd == NULL) user_cmnd = NewArgv[0]; (void) strlcpy(user_cwd, "unknown", sizeof(user_cwd)); /* * We avoid gethostbyname() if possible since we don't want * sudo to block if DNS or NIS is hosed. * "host" is the (possibly fully-qualified) hostname and * "shost" is the unqualified form of the hostname. */ nohostname = gethostname(thost, sizeof(thost)); if (nohostname) user_host = user_shost = "localhost"; else { thost[sizeof(thost) - 1] = '\0'; user_host = estrdup(thost); if (def_fqdn) { /* Defer call to set_fqdn() until log_error() is safe. */ user_shost = user_host; } else { if ((p = strchr(user_host, '.'))) { *p = '\0'; user_shost = estrdup(user_host); *p = '.'; } else { user_shost = user_host; } } } if ((p = ttyname(STDIN_FILENO)) || (p = ttyname(STDOUT_FILENO)) || (p = ttyname(STDERR_FILENO))) { user_tty = user_ttypath = estrdup(p); if (strncmp(user_tty, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0) user_tty += sizeof(_PATH_DEV) - 1; } else user_tty = "unknown"; for (ep = envp; *ep; ep++) { /* XXX - don't fill in if empty string */ switch (**ep) { case 'D': if (strncmp("DISPLAY=", *ep, 8) == 0) user_display = *ep + 8; break; case 'K': if (strncmp("KRB5CCNAME=", *ep, 11) == 0) user_ccname = *ep + 11; break; case 'P': if (strncmp("PATH=", *ep, 5) == 0) user_path = *ep + 5; break; case 'S': if (strncmp("SHELL=", *ep, 6) == 0) user_shell = *ep + 6; else if (!user_prompt && strncmp("SUDO_PROMPT=", *ep, 12) == 0) user_prompt = *ep + 12; else if (strncmp("SUDO_USER=", *ep, 10) == 0) prev_user = *ep + 10; else if (strncmp("SUDO_ASKPASS=", *ep, 13) == 0) user_askpass = *ep + 13; break; } } /* * Get a local copy of the user's struct passwd with the shadow password * if necessary. It is assumed that euid is 0 at this point so we * can read the shadow passwd file if necessary. */ if ((sudo_user.pw = sudo_getpwuid(getuid())) == NULL) { /* Need to make a fake struct passwd for logging to work. */ struct passwd pw; char pw_name[MAX_UID_T_LEN + 1]; pw.pw_uid = getuid(); (void) snprintf(pw_name, sizeof(pw_name), "%lu", (unsigned long) pw.pw_uid); pw.pw_name = pw_name; sudo_user.pw = &pw; /* * If we are in -k/-K mode, just spew to stderr. It is not unusual for * users to place "sudo -k" in a .logout file which can cause sudo to * be run during reboot after the YP/NIS/NIS+/LDAP/etc daemon has died. */ if (sudo_mode == MODE_KILL || sudo_mode == MODE_INVALIDATE) errorx(1, "unknown uid: %s", pw_name); log_error(0, "unknown uid: %s", pw_name); } if (user_shell == NULL || *user_shell == '\0') user_shell = estrdup(sudo_user.pw->pw_shell); /* It is now safe to use log_error() and set_perms() */ #ifdef HAVE_GETGROUPS if ((user_ngroups = getgroups(0, NULL)) > 0) { user_groups = emalloc2(user_ngroups, sizeof(GETGROUPS_T)); if (getgroups(user_ngroups, user_groups) < 0) log_error(USE_ERRNO|MSG_ONLY, "can't get group vector"); } else user_ngroups = 0; #endif if (def_fqdn) set_fqdn(); /* may call log_error() */ if (nohostname) log_error(USE_ERRNO|MSG_ONLY, "can't get hostname"); /* * Get current working directory. Try as user, fall back to root. */ set_perms(PERM_USER); if (!getcwd(user_cwd, sizeof(user_cwd))) { set_perms(PERM_ROOT); if (!getcwd(user_cwd, sizeof(user_cwd))) { warningx("cannot get working directory"); (void) strlcpy(user_cwd, "unknown", sizeof(user_cwd)); } } else set_perms(PERM_ROOT); /* * If we were given the '-e', '-i' or '-s' options we need to redo * NewArgv and NewArgc. */ if (ISSET(sudo_mode, MODE_EDIT)) { NewArgv--; NewArgc++; NewArgv[0] = "sudoedit"; } else if (ISSET(sudo_mode, MODE_SHELL)) { char **av; /* Allocate an extra slot for execve() failure (ENOEXEC). */ av = (char **) emalloc2(5, sizeof(char *)); av++; av[0] = user_shell; /* may be updated later */ if (NewArgc > 0) { size_t size; char *cmnd, *src, *dst, *end; size = (size_t) (NewArgv[NewArgc - 1] - NewArgv[0]) + strlen(NewArgv[NewArgc - 1]) + 1; cmnd = emalloc(size); src = NewArgv[0]; dst = cmnd; for (end = src + size - 1; src < end; src++, dst++) *dst = *src == 0 ? ' ' : *src; *dst = '\0'; av[1] = "-c"; av[2] = cmnd; NewArgc = 2; } av[++NewArgc] = NULL; NewArgv = av; } } /* * Fill in user_cmnd, user_args, user_base and user_stat variables * and apply any command-specific defaults entries. */ static int set_cmnd(sudo_mode) int sudo_mode; { int rval; /* Set project if applicable. */ set_project(runas_pw); /* Resolve the path and return. */ rval = FOUND; user_stat = emalloc(sizeof(struct stat)); if (sudo_mode & (MODE_RUN | MODE_EDIT | MODE_CHECK)) { if (ISSET(sudo_mode, MODE_RUN | MODE_CHECK)) { set_perms(PERM_RUNAS); rval = find_path(NewArgv[0], &user_cmnd, user_stat, user_path); set_perms(PERM_ROOT); if (rval != FOUND) { /* Failed as root, try as invoking user. */ set_perms(PERM_USER); rval = find_path(NewArgv[0], &user_cmnd, user_stat, user_path); set_perms(PERM_ROOT); } } /* set user_args */ if (NewArgc > 1) { char *to, **from; size_t size, n; /* If we didn't realloc NewArgv it is contiguous so just count. */ if (!ISSET(sudo_mode, MODE_SHELL)) { size = (size_t) (NewArgv[NewArgc-1] - NewArgv[1]) + strlen(NewArgv[NewArgc-1]) + 1; } else { for (size = 0, from = NewArgv + 1; *from; from++) size += strlen(*from) + 1; } /* Alloc and build up user_args. */ user_args = (char *) emalloc(size); for (to = user_args, from = NewArgv + 1; *from; from++) { n = strlcpy(to, *from, size - (to - user_args)); if (n >= size - (to - user_args)) errorx(1, "internal error, init_vars() overflow"); to += n; *to++ = ' '; } *--to = '\0'; } } if ((user_base = strrchr(user_cmnd, '/')) != NULL) user_base++; else user_base = user_cmnd; if (!update_defaults(SETDEF_CMND)) log_error(NO_STDERR|NO_EXIT, "problem with defaults entries"); if (!runas_user && !runas_group) set_runaspw(def_runas_default); /* may have been updated above */ return(rval); } /* * Command line argument parsing. * Sets NewArgc and NewArgv which corresponds to the argc/argv we'll use * for the command to be run (if we are running one). */ static int parse_args(argc, argv) int argc; char **argv; { int mode = 0; /* what mode is sudo to be run in? */ int flags = 0; /* mode flags */ int valid_flags, ch; /* First, check to see if we were invoked as "sudoedit". */ if (strcmp(getprogname(), "sudoedit") == 0) mode = MODE_EDIT; /* Returns true if the last option string was "--" */ #define got_end_of_args (optind > 1 && argv[optind - 1][0] == '-' && \ argv[optind - 1][1] == '-' && argv[optind - 1][2] == '\0') /* Returns true if next option is an environment variable */ #define is_envar (optind < argc && argv[optind][0] != '/' && \ strchr(argv[optind], '=') != NULL) /* Flags allowed when running a command */ valid_flags = MODE_BACKGROUND|MODE_PRESERVE_ENV|MODE_RESET_HOME| MODE_LOGIN_SHELL|MODE_INVALIDATE|MODE_NONINTERACTIVE| MODE_PRESERVE_GROUPS|MODE_SHELL; for (;;) { /* * We disable arg permutation for GNU getopt(). * Some trickiness is required to allow environment variables * to be interspersed with command line options. */ if ((ch = getopt(argc, argv, "+Aa:bC:c:Eeg:HhiKkLlnPp:r:Sst:U:u:Vv")) != -1) { switch (ch) { case 'A': SET(tgetpass_flags, TGP_ASKPASS); break; #ifdef HAVE_BSD_AUTH_H case 'a': login_style = optarg; break; #endif case 'b': SET(flags, MODE_BACKGROUND); break; case 'C': if ((user_closefrom = atoi(optarg)) < 3) { warningx("the argument to -C must be at least 3"); usage(1); } break; #ifdef HAVE_LOGIN_CAP_H case 'c': login_class = optarg; def_use_loginclass = TRUE; break; #endif case 'E': SET(flags, MODE_PRESERVE_ENV); break; case 'e': if (mode && mode != MODE_EDIT) usage_excl(1); mode = MODE_EDIT; valid_flags = MODE_INVALIDATE|MODE_NONINTERACTIVE; break; case 'g': runas_group = optarg; break; case 'H': SET(flags, MODE_RESET_HOME); break; case 'h': if (mode && mode != MODE_HELP) { if (strcmp(getprogname(), "sudoedit") != 0) usage_excl(1); } mode = MODE_HELP; valid_flags = 0; break; case 'i': SET(flags, MODE_LOGIN_SHELL); def_env_reset = TRUE; break; case 'k': SET(flags, MODE_INVALIDATE); break; case 'K': if (mode && mode != MODE_KILL) usage_excl(1); mode = MODE_KILL; valid_flags = 0; break; case 'L': if (mode && mode != MODE_LISTDEFS) usage_excl(1); mode = MODE_LISTDEFS; valid_flags = MODE_INVALIDATE|MODE_NONINTERACTIVE; break; case 'l': if (mode) { if (mode == MODE_LIST) long_list = 1; else usage_excl(1); } mode = MODE_LIST; valid_flags = MODE_INVALIDATE|MODE_NONINTERACTIVE; break; case 'n': SET(flags, MODE_NONINTERACTIVE); break; case 'P': SET(flags, MODE_PRESERVE_GROUPS); break; case 'p': user_prompt = optarg; def_passprompt_override = TRUE; break; #ifdef HAVE_SELINUX case 'r': user_role = optarg; break; case 't': user_type = optarg; break; #endif case 'S': SET(tgetpass_flags, TGP_STDIN); break; case 's': SET(flags, MODE_SHELL); break; case 'U': if ((list_pw = sudo_getpwnam(optarg)) == NULL) errorx(1, "unknown user: %s", optarg); break; case 'u': runas_user = optarg; break; case 'v': if (mode && mode != MODE_VALIDATE) usage_excl(1); mode = MODE_VALIDATE; valid_flags = MODE_INVALIDATE|MODE_NONINTERACTIVE; break; case 'V': if (mode && mode != MODE_VERSION) usage_excl(1); mode = MODE_VERSION; valid_flags = 0; break; default: usage(1); } } else if (!got_end_of_args && is_envar) { struct list_member *ev; /* Store environment variable. */ ev = emalloc(sizeof(*ev)); ev->value = argv[optind]; ev->next = sudo_user.env_vars; sudo_user.env_vars = ev; /* Crank optind and resume getopt. */ optind++; } else { /* Not an option or an environment variable -- we're done. */ break; } } NewArgc = argc - optind; NewArgv = argv + optind; if (!mode) { /* Defer -k mode setting until we know whether it is a flag or not */ if (ISSET(flags, MODE_INVALIDATE) && NewArgc == 0) { mode = MODE_INVALIDATE; /* -k by itself */ CLR(flags, MODE_INVALIDATE); valid_flags = 0; } else { mode = MODE_RUN; /* running a command */ } } if (NewArgc > 0 && mode == MODE_LIST) mode = MODE_CHECK; if (ISSET(flags, MODE_LOGIN_SHELL)) { if (ISSET(flags, MODE_SHELL)) { warningx("you may not specify both the `-i' and `-s' options"); usage(1); } if (ISSET(flags, MODE_PRESERVE_ENV)) { warningx("you may not specify both the `-i' and `-E' options"); usage(1); } SET(flags, MODE_SHELL); } if ((flags & valid_flags) != flags) usage(1); if (mode == MODE_EDIT && (ISSET(flags, MODE_PRESERVE_ENV) || sudo_user.env_vars != NULL)) { if (ISSET(mode, MODE_PRESERVE_ENV)) warningx("the `-E' option is not valid in edit mode"); if (sudo_user.env_vars != NULL) warningx("you may not specify environment variables in edit mode"); usage(1); } if ((runas_user != NULL || runas_group != NULL) && !ISSET(mode, MODE_EDIT | MODE_RUN | MODE_CHECK)) { usage(1); } if (list_pw != NULL && mode != MODE_LIST && mode != MODE_CHECK) { warningx("the `-U' option may only be used with the `-l' option"); usage(1); } if (ISSET(tgetpass_flags, TGP_STDIN) && ISSET(tgetpass_flags, TGP_ASKPASS)) { warningx("the `-A' and `-S' options may not be used together"); usage(1); } if ((NewArgc == 0 && mode == MODE_EDIT) || (NewArgc > 0 && !ISSET(mode, MODE_RUN | MODE_EDIT | MODE_CHECK))) usage(1); if (NewArgc == 0 && mode == MODE_RUN && !ISSET(flags, MODE_SHELL)) SET(flags, (MODE_IMPLIED_SHELL | MODE_SHELL)); return(mode | flags); } /* * Open sudoers and sanity check mode/owner/type. * Returns a handle to the sudoers file or NULL on error. */ FILE * open_sudoers(sudoers, doedit, keepopen) const char *sudoers; int doedit; int *keepopen; { struct stat statbuf; FILE *fp = NULL; int rootstat; /* * Fix the mode and group on sudoers file from old default. * Only works if file system is readable/writable by root. */ if ((rootstat = stat_sudoers(sudoers, &statbuf)) == 0 && SUDOERS_UID == statbuf.st_uid && SUDOERS_MODE != 0400 && (statbuf.st_mode & 0007777) == 0400) { if (chmod(sudoers, SUDOERS_MODE) == 0) { warningx("fixed mode on %s", sudoers); SET(statbuf.st_mode, SUDOERS_MODE); if (statbuf.st_gid != SUDOERS_GID) { if (chown(sudoers, (uid_t) -1, SUDOERS_GID) == 0) { warningx("set group on %s", sudoers); statbuf.st_gid = SUDOERS_GID; } else warning("unable to set group on %s", sudoers); } } else warning("unable to fix mode on %s", sudoers); } /* * Sanity checks on sudoers file. Must be done as sudoers * file owner. We already did a stat as root, so use that * data if we can't stat as sudoers file owner. */ set_perms(PERM_SUDOERS); if (rootstat != 0 && stat_sudoers(sudoers, &statbuf) != 0) log_error(USE_ERRNO|NO_EXIT, "can't stat %s", sudoers); else if (!S_ISREG(statbuf.st_mode)) log_error(NO_EXIT, "%s is not a regular file", sudoers); else if ((statbuf.st_mode & 07777) != SUDOERS_MODE) log_error(NO_EXIT, "%s is mode 0%o, should be 0%o", sudoers, (unsigned int) (statbuf.st_mode & 07777), (unsigned int) SUDOERS_MODE); else if (statbuf.st_uid != SUDOERS_UID) log_error(NO_EXIT, "%s is owned by uid %lu, should be %lu", sudoers, (unsigned long) statbuf.st_uid, (unsigned long) SUDOERS_UID); else if (statbuf.st_gid != SUDOERS_GID) log_error(NO_EXIT, "%s is owned by gid %lu, should be %lu", sudoers, (unsigned long) statbuf.st_gid, (unsigned long) SUDOERS_GID); else if ((fp = fopen(sudoers, "r")) == NULL) log_error(USE_ERRNO|NO_EXIT, "can't open %s", sudoers); else { /* * Make sure we can actually read sudoers so we can present the * user with a reasonable error message (unlike the lexer). */ if (statbuf.st_size != 0 && fgetc(fp) == EOF) { log_error(USE_ERRNO|NO_EXIT, "can't read %s", sudoers); fclose(fp); fp = NULL; } } if (fp != NULL) { rewind(fp); (void) fcntl(fileno(fp), F_SETFD, 1); } set_perms(PERM_ROOT); /* change back to root */ return(fp); } /* * Close all open files (except std*) and turn off core dumps. * Also sets the set_perms() pointer to the correct function. */ static void initial_setup() { int miss[3], devnull = -1; #if defined(__linux__) || (defined(RLIMIT_CORE) && !defined(SUDO_DEVEL)) struct rlimit rl; #endif #if defined(__linux__) /* * Unlimit the number of processes since Linux's setuid() will * apply resource limits when changing uid and return EAGAIN if * nproc would be violated by the uid switch. */ rl.rlim_cur = rl.rlim_max = RLIM_INFINITY; if (setrlimit(RLIMIT_NPROC, &rl)) { if (getrlimit(RLIMIT_NPROC, &rl) == 0) { rl.rlim_cur = rl.rlim_max; (void)setrlimit(RLIMIT_NPROC, &rl); } } #endif /* __linux__ */ #if defined(RLIMIT_CORE) && !defined(SUDO_DEVEL) /* * Turn off core dumps. */ (void) getrlimit(RLIMIT_CORE, &corelimit); memcpy(&rl, &corelimit, sizeof(struct rlimit)); rl.rlim_cur = 0; (void) setrlimit(RLIMIT_CORE, &rl); #endif /* RLIMIT_CORE && !SUDO_DEVEL */ /* * stdin, stdout and stderr must be open; set them to /dev/null * if they are closed and close all other fds. */ miss[STDIN_FILENO] = fcntl(STDIN_FILENO, F_GETFL, 0) == -1; miss[STDOUT_FILENO] = fcntl(STDOUT_FILENO, F_GETFL, 0) == -1; miss[STDERR_FILENO] = fcntl(STDERR_FILENO, F_GETFL, 0) == -1; if (miss[STDIN_FILENO] || miss[STDOUT_FILENO] || miss[STDERR_FILENO]) { if ((devnull = open(_PATH_DEVNULL, O_RDWR, 0644)) != -1) { if (miss[STDIN_FILENO]) (void) dup2(devnull, STDIN_FILENO); if (miss[STDOUT_FILENO]) (void) dup2(devnull, STDOUT_FILENO); if (miss[STDERR_FILENO]) (void) dup2(devnull, STDERR_FILENO); if (devnull > STDERR_FILENO) close(devnull); } } } #ifdef HAVE_LOGIN_CAP_H static void set_loginclass(pw) struct passwd *pw; { int errflags; /* * Don't make it a fatal 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. */ if (login_class) errflags = NO_MAIL|MSG_ONLY; else errflags = NO_MAIL|MSG_ONLY|NO_EXIT; if (login_class && strcmp(login_class, "-") != 0) { if (user_uid != 0 && strcmp(runas_user ? runas_user : def_runas_default, "root") != 0) errorx(1, "only root can use -c %s", login_class); } else { login_class = pw->pw_class; if (!login_class || !*login_class) login_class = (pw->pw_uid == 0) ? LOGIN_DEFROOTCLASS : LOGIN_DEFCLASS; } lc = login_getclass(login_class); if (!lc || !lc->lc_class || strcmp(lc->lc_class, login_class) != 0) { log_error(errflags, "unknown login class: %s", login_class); if (!lc) lc = login_getclass(NULL); /* needed for login_getstyle() later */ } } #else static void set_loginclass(pw) struct passwd *pw; { } #endif /* HAVE_LOGIN_CAP_H */ #ifdef HAVE_PROJECT_H static void set_project(pw) struct passwd *pw; { int errflags = NO_MAIL|MSG_ONLY|NO_EXIT; int errval; struct project proj; struct project *resultp = '\0'; char buf[1024]; /* * Collect the default project for the user and settaskid */ setprojent(); if (resultp = getdefaultproj(pw->pw_name, &proj, buf, sizeof(buf))) { errval = setproject(resultp->pj_name, pw->pw_name, TASK_NORMAL); if (errval != 0) { switch(errval) { case SETPROJ_ERR_TASK: if (errno == EAGAIN) log_error(errflags, "resource control limit has been reached"); else if (errno == ESRCH) log_error(errflags, "user \"%s\" is not a member of " "project \"%s\"", pw->pw_name, resultp->pj_name); else if (errno == EACCES) log_error(errflags, "the invoking task is final"); else log_error(errflags, "could not join project \"%s\"", resultp->pj_name); break; case SETPROJ_ERR_POOL: if (errno == EACCES) log_error(errflags, "no resource pool accepting " "default bindings exists for project \"%s\"", resultp->pj_name); else if (errno == ESRCH) log_error(errflags, "specified resource pool does " "not exist for project \"%s\"", resultp->pj_name); else log_error(errflags, "could not bind to default " "resource pool for project \"%s\"", resultp->pj_name); break; default: if (errval <= 0) { log_error(errflags, "setproject failed for project \"%s\"", resultp->pj_name); } else { log_error(errflags, "warning, resource control assignment " "failed for project \"%s\"", resultp->pj_name); } } } } else { log_error(errflags, "getdefaultproj() error: %s", strerror(errno)); } endprojent(); } #else static void set_project(pw) struct passwd *pw; { } #endif /* HAVE_PROJECT_H */ /* * Look up the fully qualified domain name and set user_host and user_shost. */ void set_fqdn() { #ifdef HAVE_GETADDRINFO struct addrinfo *res0, hint; #else struct hostent *hp; #endif char *p; #ifdef HAVE_GETADDRINFO zero_bytes(&hint, sizeof(hint)); hint.ai_family = PF_UNSPEC; hint.ai_flags = AI_CANONNAME; if (getaddrinfo(user_host, NULL, &hint, &res0) != 0) { #else if (!(hp = gethostbyname(user_host))) { #endif log_error(MSG_ONLY|NO_EXIT, "unable to resolve host %s", user_host); } else { if (user_shost != user_host) efree(user_shost); efree(user_host); #ifdef HAVE_GETADDRINFO user_host = estrdup(res0->ai_canonname); freeaddrinfo(res0); #else user_host = estrdup(hp->h_name); #endif } if ((p = strchr(user_host, '.'))) { *p = '\0'; user_shost = estrdup(user_host); *p = '.'; } else { user_shost = user_host; } } /* * Get passwd entry for the user we are going to run commands as. * By default, this is "root". Updates runas_pw as a side effect. */ static void set_runaspw(user) char *user; { if (*user == '#') { if ((runas_pw = sudo_getpwuid(atoi(user + 1))) == NULL) runas_pw = sudo_fakepwnam(user, runas_gr ? runas_gr->gr_gid : 0); } else { if ((runas_pw = sudo_getpwnam(user)) == NULL) { audit_failure(NewArgv, "unknown user: %s", user); log_error(NO_MAIL|MSG_ONLY, "unknown user: %s", user); } } } /* * Get group entry for the group we are going to run commands as. * Updates runas_pw as a side effect. */ static void set_runasgr(group) char *group; { if (*group == '#') { if ((runas_gr = sudo_getgrgid(atoi(group + 1))) == NULL) runas_gr = sudo_fakegrnam(group); } else { if ((runas_gr = sudo_getgrnam(group)) == NULL) log_error(NO_MAIL|MSG_ONLY, "unknown group: %s", group); } } /* * Get passwd entry for the user we are going to authenticate as. * By default, this is the user invoking sudo. In the most common * case, this matches sudo_user.pw or runas_pw. */ static struct passwd * get_authpw() { struct passwd *pw; if (def_rootpw) { if ((pw = sudo_getpwuid(0)) == NULL) log_error(0, "unknown uid: 0"); } else if (def_runaspw) { if ((pw = sudo_getpwnam(def_runas_default)) == NULL) log_error(0, "unknown user: %s", def_runas_default); } else if (def_targetpw) { if (runas_pw->pw_name == NULL) log_error(NO_MAIL|MSG_ONLY, "unknown uid: %lu", (unsigned long) runas_pw->pw_uid); pw = runas_pw; } else pw = sudo_user.pw; return(pw); } /* * Cleanup hook for error()/errorx() */ void cleanup(gotsignal) int gotsignal; { struct sudo_nss *nss; if (!gotsignal) { if (snl != NULL) { tq_foreach_fwd(snl, nss) nss->close(nss); } #ifdef USING_NONUNIX_GROUPS sudo_nonunix_groupcheck_cleanup(); #endif sudo_endpwent(); sudo_endgrent(); } } static void show_version() { (void) printf("Sudo version %s\n", PACKAGE_VERSION); if (getuid() == 0) { putchar('\n'); (void) printf("Sudoers path: %s\n", _PATH_SUDOERS); #ifdef HAVE_LDAP # ifdef _PATH_NSSWITCH_CONF (void) printf("nsswitch path: %s\n", _PATH_NSSWITCH_CONF); # endif (void) printf("ldap.conf path: %s\n", _PATH_LDAP_CONF); (void) printf("ldap.secret path: %s\n", _PATH_LDAP_SECRET); #endif dump_auth_methods(); dump_defaults(); dump_interfaces(); } exit(0); } /* * Tell which options are mutually exclusive and exit. */ static void usage_excl(exit_val) int exit_val; { warningx("Only one of the -e, -h, -i, -K, -l, -s, -v or -V options may be specified"); usage(exit_val); } /* * Give usage message and exit. * The actual usage strings are in sudo_usage.h for configure substitution. */ static void usage(exit_val) int exit_val; { struct lbuf lbuf; char *uvec[6]; int i, ulen; /* * Use usage vectors appropriate to the progname. */ if (strcmp(getprogname(), "sudoedit") == 0) { uvec[0] = SUDO_USAGE5 + 3; uvec[1] = NULL; } else { uvec[0] = SUDO_USAGE1; uvec[1] = SUDO_USAGE2; uvec[2] = SUDO_USAGE3; uvec[3] = SUDO_USAGE4; uvec[4] = SUDO_USAGE5; uvec[5] = NULL; } /* * Print usage and wrap lines as needed, depending on the * tty width. */ ulen = (int)strlen(getprogname()) + 8; lbuf_init(&lbuf, NULL, ulen, 0); for (i = 0; uvec[i] != NULL; i++) { lbuf_append(&lbuf, "usage: ", getprogname(), uvec[i], NULL); lbuf_print(&lbuf); } lbuf_destroy(&lbuf); exit(exit_val); }