/* * Copyright (c) 1993-1996,1998-2003 Todd C. Miller * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * 4. Products derived from this software may not be called "Sudo" nor * may "Sudo" appear in their names without specific prior written * permission from the author. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * 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 #include "config.h" #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 */ #ifdef HAVE_ERR_H # include #else # include "emul/err.h" #endif /* HAVE_ERR_H */ #include #include #include #include #include #include #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 #include "sudo.h" #include "interfaces.h" #include "version.h" #ifndef lint static const char rcsid[] = "$Sudo: sudo.c,v 1.337 2003/04/16 00:42:10 millert Exp $"; #endif /* lint */ /* * Prototypes */ static int init_vars __P((int)); static int parse_args __P((int, char **)); static void check_sudoers __P((void)); static void initial_setup __P((void)); static void set_loginclass __P((struct passwd *)); static void usage __P((int)); static void usage_excl __P((int)); static struct passwd *get_authpw __P((void)); extern void list_matches __P((void)); extern char **rebuild_env __P((int, char **)); extern char **zero_env __P((char **)); extern struct passwd *sudo_getpwnam __P((const char *)); extern struct passwd *sudo_getpwuid __P((uid_t)); /* * Globals */ int Argc, NewArgc; char **Argv, **NewArgv; struct sudo_user sudo_user; struct passwd *auth_pw; FILE *sudoers_fp; struct interface *interfaces; int num_interfaces; int tgetpass_flags; uid_t timestamp_uid; extern int errorlineno; #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 */ void (*set_perms) __P((int)); int main(argc, argv, envp) int argc; char **argv; char **envp; { int validated; int fd; int cmnd_status; int sudo_mode; int pwflag; char **new_environ; sigaction_t sa, saved_sa_int, saved_sa_quit, saved_sa_tstp, saved_sa_chld; extern int printmatches; extern char **environ; Argc = argc; Argv = argv; /* 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 */ /* Zero out the environment. */ environ = zero_env(envp); if (geteuid() != 0) errx(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. */ 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); sa.sa_handler = reapchild; (void) sigaction(SIGCHLD, &sa, &saved_sa_chld); /* * Turn off core dumps, close open files and setup set_perms(). */ initial_setup(); setpwent(); /* 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 (sudo_mode & MODE_SHELL) user_cmnd = "shell"; else switch (sudo_mode) { case MODE_VERSION: (void) printf("Sudo version %s\n", version); if (getuid() == 0) { putchar('\n'); dump_auth_methods(); dump_defaults(); dump_interfaces(); } exit(0); break; case MODE_HELP: usage(0); break; case MODE_VALIDATE: user_cmnd = "validate"; pwflag = I_VERIFYPW_I; break; case MODE_KILL: case MODE_INVALIDATE: user_cmnd = "kill"; pwflag = -1; break; case MODE_LISTDEFS: list_options(); exit(0); break; case MODE_LIST: user_cmnd = "list"; pwflag = I_LISTPW_I; printmatches = 1; break; } /* Must have a command to run... */ if (user_cmnd == NULL && NewArgc == 0) usage(1); cmnd_status = init_vars(sudo_mode); check_sudoers(); /* check mode/owner on _PATH_SUDOERS */ /* Validate the user but don't search for pseudo-commands. */ validated = sudoers_lookup(pwflag); /* * If we are using set_perms_posix() and the stay_setuid flag was not set, * set the real, effective and saved uids to 0 and use set_perms_nosuid() * instead of set_perms_posix(). */ #if !defined(HAVE_SETRESUID) && !defined(HAVE_SETREUID) && \ !defined(NO_SAVED_IDS) && defined(_SC_SAVED_IDS) && defined(_SC_VERSION) if (!def_flag(I_STAY_SETUID) && set_perms == set_perms_posix) { if (setuid(0)) { perror("setuid(0)"); exit(1); } set_perms = set_perms_nosuid; } #endif /* * Look up runas user passwd struct. If we are given a uid then * there may be no corresponding passwd(5) entry (which is OK). */ if (**user_runas == '#') { runas_pw = sudo_getpwuid(atoi(*user_runas + 1)); if (runas_pw == NULL) { runas_pw = emalloc(sizeof(struct passwd)); (void) memset((VOID *)runas_pw, 0, sizeof(struct passwd)); runas_pw->pw_uid = atoi(*user_runas + 1); } } else { runas_pw = sudo_getpwnam(*user_runas); if (runas_pw == NULL) log_error(NO_MAIL|MSG_ONLY, "no passwd entry for %s!", *user_runas); } if (safe_cmnd == NULL) safe_cmnd = user_cmnd; /* * Look up the timestamp dir owner if one is specified. */ if (def_str(I_TIMESTAMPOWNER)) { struct passwd *pw; if (*def_str(I_TIMESTAMPOWNER) == '#') pw = getpwuid(atoi(def_str(I_TIMESTAMPOWNER) + 1)); else pw = getpwnam(def_str(I_TIMESTAMPOWNER)); if (!pw) log_error(0, "timestamp owner (%s): No such user", def_str(I_TIMESTAMPOWNER)); timestamp_uid = pw->pw_uid; } /* This goes after the sudoers parse since we honor sudoers options. */ if (sudo_mode == MODE_KILL || sudo_mode == MODE_INVALIDATE) { remove_timestamp((sudo_mode == MODE_KILL)); exit(0); } if (validated & VALIDATE_ERROR) log_error(0, "parse error in %s near line %d", _PATH_SUDOERS, errorlineno); /* Is root even allowed to run sudo? */ if (user_uid == 0 && !def_flag(I_ROOT_SUDO)) { (void) fprintf(stderr, "Sorry, %s has been configured to not allow root to run it.\n", getprogname()); exit(1); } /* If given the -P option, set the "preserve_groups" flag. */ if (sudo_mode & MODE_PRESERVE_GROUPS) def_flag(I_PRESERVE_GROUPS) = TRUE; /* If no command line args and "set_home" is not set, error out. */ if ((sudo_mode & MODE_IMPLIED_SHELL) && !def_flag(I_SHELL_NOARGS)) usage(1); /* May need to set $HOME to target user if we are running a command. */ if ((sudo_mode & MODE_RUN) && (def_flag(I_ALWAYS_SET_HOME) || ((sudo_mode & MODE_SHELL) && def_flag(I_SET_HOME)))) sudo_mode |= MODE_RESET_HOME; /* Bail if a tty is required and we don't have one. */ if (def_flag(I_REQUIRETTY)) { if ((fd = open(_PATH_TTY, O_RDWR|O_NOCTTY)) == -1) log_error(NO_MAIL, "sorry, you must have a tty to run sudo"); else (void) close(fd); } /* Fill in passwd struct based on user we are authenticating as. */ auth_pw = get_authpw(); /* Require a password unless the NOPASS tag was set. */ if (!(validated & FLAG_NOPASS)) check_user(); /* Build up custom environment that avoids any nasty bits. */ new_environ = rebuild_env(sudo_mode, envp); if (validated & VALIDATE_OK) { /* Finally tell the user if the command did not exist. */ if (cmnd_status == NOT_FOUND_DOT) { warnx("ignoring `%s' found in '.'\nUse `sudo ./%s' if this is the `%s' you wish to run.", user_cmnd, user_cmnd, user_cmnd); exit(1); } else if (cmnd_status == NOT_FOUND) { warnx("%s: command not found", user_cmnd); exit(1); } log_auth(validated, 1); if (sudo_mode == MODE_VALIDATE) exit(0); else if (sudo_mode == MODE_LIST) { list_matches(); exit(0); } /* Override user's umask if configured to do so. */ if (def_ival(I_UMASK) != 0777) (void) umask(def_mode(I_UMASK)); /* Restore coredumpsize resource limit. */ #if defined(RLIMIT_CORE) && !defined(SUDO_DEVEL) (void) setrlimit(RLIMIT_CORE, &corelimit); #endif /* RLIMIT_CORE && !SUDO_DEVEL */ /* Become specified user or root. */ set_perms(PERM_RUNAS); /* Close the password and group files */ endpwent(); endgrent(); /* Install the new environment. */ environ = new_environ; /* 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); (void) sigaction(SIGCHLD, &saved_sa_chld, NULL); #ifndef PROFILING if ((sudo_mode & MODE_BACKGROUND) && fork() > 0) exit(0); else EXEC(safe_cmnd, NewArgv); /* run the command */ #else exit(0); #endif /* PROFILING */ /* * If we got here then the exec() failed... */ warn("unable to execute %s", safe_cmnd); exit(127); } else if ((validated & FLAG_NO_USER) || (validated & FLAG_NO_HOST)) { log_auth(validated, 1); exit(1); } else if (validated & VALIDATE_NOT_OK) { if (def_flag(I_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_auth(validated, !(cmnd_status == NOT_FOUND_DOT || cmnd_status == NOT_FOUND)); if (cmnd_status == NOT_FOUND) warnx("%s: command not found", user_cmnd); else if (cmnd_status == NOT_FOUND_DOT) warnx("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_auth(validated, 1); } exit(1); } else { /* should never get here */ log_auth(validated, 1); exit(1); } exit(0); /* not reached */ } /* * Initialize timezone, set umask, fill in ``sudo_user'' struct and * load the ``interfaces'' array. */ static int init_vars(sudo_mode) int sudo_mode; { char *p, thost[MAXHOSTNAMELEN]; int nohostname, rval; /* Sanity check command from user. */ if (user_cmnd == NULL && strlen(NewArgv[0]) >= MAXPATHLEN) errx(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 { user_host = estrdup(thost); if (def_flag(I_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))) { if (strncmp(p, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0) p += sizeof(_PATH_DEV) - 1; user_tty = estrdup(p); } else user_tty = "unknown"; /* * 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_INVALIDATE|MODE_KILL)) errx(1, "uid %s does not exist in the passwd file!", pw_name); log_error(0, "uid %s does not exist in the passwd file!", pw_name); } if (user_shell == NULL || *user_shell == '\0') user_shell = sudo_user.pw->pw_shell; /* It is now safe to use log_error() and set_perms() */ /* * Must defer set_fqdn() until it is safe to call log_error() */ if (def_flag(I_FQDN)) set_fqdn(); 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))) { warnx("cannot get working directory"); (void) strlcpy(user_cwd, "unknown", sizeof(user_cwd)); } } else set_perms(PERM_ROOT); /* * If we were given the '-s' option (run shell) we need to redo * NewArgv and NewArgc. */ if ((sudo_mode & MODE_SHELL)) { char **dst, **src = NewArgv; NewArgv = (char **) emalloc2((++NewArgc + 1), sizeof(char *)); if (user_shell && *user_shell) { NewArgv[0] = user_shell; } else errx(1, "unable to determine shell"); /* copy the args from NewArgv */ for (dst = NewArgv + 1; (*dst = *src) != NULL; ++src, ++dst) ; } /* Set login class if applicable. */ set_loginclass(sudo_user.pw); /* Resolve the path and return. */ if ((sudo_mode & MODE_RUN)) { /* XXX - should call this as runas user, not root. */ rval = find_path(NewArgv[0], &user_cmnd, user_path); if (rval != FOUND) { /* Failed as root, try as invoking user. */ set_perms(PERM_USER); rval = find_path(NewArgv[0], &user_cmnd, user_path); set_perms(PERM_ROOT); } /* set user_args */ if (NewArgc > 1) { char *to, **from; size_t size, n; /* If MODE_SHELL not set then NewArgv is contiguous so just count */ if (!(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 copy. */ 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)) errx(1, "internal error, init_vars() overflow"); to += n; *to++ = ' '; } *--to = '\0'; } } else rval = FOUND; return(rval); } /* * Command line argument parsing, can't use getopt(3). */ static int parse_args(argc, argv) int argc; char **argv; { int rval = MODE_RUN; /* what mode is sudo to be run in? */ int excl = 0; /* exclusive arg, no others allowed */ NewArgv = argv + 1; NewArgc = argc - 1; if (NewArgc == 0) { /* no options and no command */ rval |= (MODE_IMPLIED_SHELL | MODE_SHELL); return(rval); } while (NewArgc > 0 && NewArgv[0][0] == '-') { if (NewArgv[0][1] != '\0' && NewArgv[0][2] != '\0') warnx("please use single character options"); switch (NewArgv[0][1]) { case 'p': /* Must have an associated prompt. */ if (NewArgv[1] == NULL) usage(1); user_prompt = NewArgv[1]; NewArgc--; NewArgv++; break; case 'u': /* Must have an associated runas user. */ if (NewArgv[1] == NULL) usage(1); user_runas = &NewArgv[1]; NewArgc--; NewArgv++; break; #ifdef HAVE_BSD_AUTH_H case 'a': /* Must have an associated authentication style. */ if (NewArgv[1] == NULL) usage(1); login_style = NewArgv[1]; NewArgc--; NewArgv++; break; #endif #ifdef HAVE_LOGIN_CAP_H case 'c': /* Must have an associated login class. */ if (NewArgv[1] == NULL) usage(1); login_class = NewArgv[1]; def_flag(I_USE_LOGINCLASS) = TRUE; NewArgc--; NewArgv++; break; #endif case 'b': rval |= MODE_BACKGROUND; break; case 'v': rval = MODE_VALIDATE; if (excl && excl != 'v') usage_excl(1); excl = 'v'; break; case 'k': rval = MODE_INVALIDATE; if (excl && excl != 'k') usage_excl(1); excl = 'k'; break; case 'K': rval = MODE_KILL; if (excl && excl != 'K') usage_excl(1); excl = 'K'; break; case 'L': rval = MODE_LISTDEFS; if (excl && excl != 'L') usage_excl(1); excl = 'L'; break; case 'l': rval = MODE_LIST; if (excl && excl != 'l') usage_excl(1); excl = 'l'; break; case 'V': rval = MODE_VERSION; if (excl && excl != 'V') usage_excl(1); excl = 'V'; break; case 'h': rval = MODE_HELP; if (excl && excl != 'h') usage_excl(1); excl = 'h'; break; case 's': rval |= MODE_SHELL; if (excl && excl != 's') usage_excl(1); excl = 's'; break; case 'H': rval |= MODE_RESET_HOME; break; case 'P': rval |= MODE_PRESERVE_GROUPS; break; case 'S': tgetpass_flags |= TGP_STDIN; break; case '-': NewArgc--; NewArgv++; if (rval == MODE_RUN) rval |= (MODE_IMPLIED_SHELL | MODE_SHELL); return(rval); case '\0': warnx("'-' requires an argument"); usage(1); default: warnx("illegal option `%s'", NewArgv[0]); usage(1); } NewArgc--; NewArgv++; } if (NewArgc > 0 && !(rval & MODE_RUN)) usage(1); return(rval); } /* * Sanity check sudoers mode/owner/type. * Leaves a file pointer to the sudoers file open in ``fp''. */ static void check_sudoers() { struct stat statbuf; int rootstat, i; char c; /* * Fix the mode and group on sudoers file from old default. * Only works if filesystem is readable/writable by root. */ if ((rootstat = stat_sudoers(_PATH_SUDOERS, &statbuf)) == 0 && SUDOERS_UID == statbuf.st_uid && SUDOERS_MODE != 0400 && (statbuf.st_mode & 0007777) == 0400) { if (chmod(_PATH_SUDOERS, SUDOERS_MODE) == 0) { warnx("fixed mode on %s", _PATH_SUDOERS); statbuf.st_mode |= SUDOERS_MODE; if (statbuf.st_gid != SUDOERS_GID) { if (!chown(_PATH_SUDOERS,(uid_t) -1,SUDOERS_GID)) { warnx("set group on %s", _PATH_SUDOERS); statbuf.st_gid = SUDOERS_GID; } else warn("unable to set group on %s", _PATH_SUDOERS); } } else warn("unable to fix mode on %s", _PATH_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(_PATH_SUDOERS, &statbuf) != 0) log_error(USE_ERRNO, "can't stat %s", _PATH_SUDOERS); else if (!S_ISREG(statbuf.st_mode)) log_error(0, "%s is not a regular file", _PATH_SUDOERS); else if (statbuf.st_size == 0) log_error(0, "%s is zero length", _PATH_SUDOERS); else if ((statbuf.st_mode & 07777) != SUDOERS_MODE) log_error(0, "%s is mode 0%o, should be 0%o", _PATH_SUDOERS, (statbuf.st_mode & 07777), SUDOERS_MODE); else if (statbuf.st_uid != SUDOERS_UID) log_error(0, "%s is owned by uid %lu, should be %lu", _PATH_SUDOERS, (unsigned long) statbuf.st_uid, SUDOERS_UID); else if (statbuf.st_gid != SUDOERS_GID) log_error(0, "%s is owned by gid %lu, should be %lu", _PATH_SUDOERS, (unsigned long) statbuf.st_gid, SUDOERS_GID); else { /* Solaris sometimes returns EAGAIN so try 10 times */ for (i = 0; i < 10 ; i++) { errno = 0; if ((sudoers_fp = fopen(_PATH_SUDOERS, "r")) == NULL || fread(&c, sizeof(c), 1, sudoers_fp) != 1) { sudoers_fp = NULL; if (errno != EAGAIN && errno != EWOULDBLOCK) break; } else break; sleep(1); } if (sudoers_fp == NULL) log_error(USE_ERRNO, "can't open %s", _PATH_SUDOERS); } set_perms(PERM_ROOT); /* change back to root */ } /* * 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() { #if defined(RLIMIT_CORE) && !defined(SUDO_DEVEL) struct rlimit rl; /* * 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 */ closefrom(STDERR_FILENO + 1); /* * Make set_perms point to the correct function. * If we are using setresuid() or setreuid() we only need to set this * once. If we are using POSIX saved uids we will switch to * set_perms_nosuid after sudoers has been parsed if the "stay_suid" * option is not set. */ #if defined(HAVE_SETRESUID) || defined(HAVE_SETREUID) set_perms = set_perms_suid; #else # if !defined(NO_SAVED_IDS) && defined(_SC_SAVED_IDS) && defined(_SC_VERSION) if (sysconf(_SC_SAVED_IDS) == 1 && sysconf(_SC_VERSION) >= 199009) set_perms = set_perms_posix; else # endif set_perms = set_perms_nosuid; #endif /* HAVE_SETRESUID || HAVE_SETREUID */ } #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 (strcmp(*user_runas, "root") != 0 && user_uid != 0) errx(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 */ /* * Look up the fully qualified domain name and set user_host and user_shost. */ void set_fqdn() { struct hostent *hp; char *p; if (!(hp = gethostbyname(user_host))) { log_error(MSG_ONLY|NO_EXIT, "unable to lookup %s via gethostbyname()", user_host); } else { if (user_shost != user_host) free(user_shost); free(user_host); user_host = estrdup(hp->h_name); } 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 authenticate as. * By default, this is the user invoking sudo... */ static struct passwd * get_authpw() { struct passwd *pw; if (def_ival(I_ROOTPW)) { if ((pw = sudo_getpwuid(0)) == NULL) log_error(0, "uid 0 does not exist in the passwd file!"); } else if (def_ival(I_RUNASPW)) { if ((pw = sudo_getpwnam(def_str(I_RUNAS_DEFAULT))) == NULL) log_error(0, "user %s does not exist in the passwd file!", def_str(I_RUNAS_DEFAULT)); } else if (def_ival(I_TARGETPW)) { if (**user_runas == '#') { if ((pw = sudo_getpwuid(atoi(*user_runas + 1))) == NULL) log_error(0, "uid %s does not exist in the passwd file!", user_runas); } else { if ((pw = sudo_getpwnam(*user_runas)) == NULL) log_error(0, "user %s does not exist in the passwd file!", user_runas); } } else pw = sudo_user.pw; return(pw); } /* * Tell which options are mutually exclusive and exit. */ static void usage_excl(exit_val) int exit_val; { (void) fprintf(stderr, "Only one of the -h, -k, -K, -l, -s, -v or -V options may be used\n"); usage(exit_val); } /* * Give usage message and exit. */ static void usage(exit_val) int exit_val; { (void) fprintf(stderr, "usage: sudo -V | -h | -L | -l | -v | -k | -K | %s", "[-H] [-P] [-S] [-b] [-p prompt]\n [-u username/#uid] "); #ifdef HAVE_LOGIN_CAP_H (void) fprintf(stderr, "[-c class] "); #endif #ifdef HAVE_BSD_AUTH_H (void) fprintf(stderr, "[-a auth_type] "); #endif (void) fprintf(stderr, "-s | \n"); exit(exit_val); }