NetBSD/usr.bin/crontab/crontab.c

478 lines
9.1 KiB
C

#ifndef lint
static char rcsid[] = "$Id: crontab.c,v 1.4 1993/08/02 17:53:24 mycroft Exp $";
#endif /* not lint */
#define MAIN_PROGRAM
#include "cron.h"
#include <pwd.h>
#include <errno.h>
#include <sys/file.h>
#if defined(BSD)
# include <sys/time.h>
#endif /*BSD*/
static int Pid;
static char User[MAX_UNAME], RealUser[MAX_UNAME];
static char Filename[MAX_FNAME];
static FILE *NewCrontab;
static int CheckErrorCount;
static enum {opt_unknown, opt_list, opt_delete, opt_edit, opt_replace}
Option;
extern char *getenv(), *strcpy();
extern int getuid();
extern struct passwd *getpwnam();
extern int getopt(), optind;
extern char *optarg;
extern void log_it(); /* misc.c */
#if DEBUGGING
static char *Options[] = {"???", "list", "delete", "edit", "replace"};
#endif
static void
usage()
{
fprintf(stderr, "usage: %s [-u user] ...\n", ProgramName);
fprintf(stderr, " ... -l (list user's crontab)\n");
fprintf(stderr, " ... -d (delete user's crontab)\n");
fprintf(stderr, " ... -e (edit user's crontab)\n");
fprintf(stderr, " ... -r file (replace user's crontab)\n");
exit(ERROR_EXIT);
}
main(argc, argv)
int argc;
char *argv[];
{
void parse_args(), set_cron_uid(), set_cron_cwd(),
list_cmd(), delete_cmd(), edit_cmd(), replace_cmd();
Pid = getpid();
ProgramName = argv[0];
#if defined(BSD)
setlinebuf(stderr);
#endif
parse_args(argc, argv); /* sets many globals, opens a file */
set_cron_uid();
set_cron_cwd();
if (!allowed(User)) {
fprintf(stderr,
"You (%s) are not allowed to use this program (%s)\n",
User, ProgramName);
fprintf(stderr, "See crontab(1) for more information\n");
log_it(RealUser, Pid, "AUTH", "crontab command not allowed");
exit(ERROR_EXIT);
}
switch (Option)
{
case opt_list: list_cmd();
break;
case opt_delete: delete_cmd();
break;
case opt_edit: edit_cmd();
break;
case opt_replace: replace_cmd();
break;
}
}
static void
parse_args(argc, argv)
int argc;
char *argv[];
{
void usage();
struct passwd *pw;
int argch;
if (!(pw = getpwuid(getuid())))
{
fprintf(stderr, "%s: your UID isn't in the passwd file.\n",
ProgramName);
fprintf(stderr, "bailing out.\n");
exit(ERROR_EXIT);
}
strcpy(User, pw->pw_name);
strcpy(RealUser, User);
Filename[0] = '\0';
Option = opt_unknown;
while (EOF != (argch = getopt(argc, argv, "u:lder:x:")))
{
switch (argch)
{
case 'x':
if (!set_debug_flags(optarg))
usage();
break;
case 'u':
if (getuid() != ROOT_UID)
{
fprintf(stderr,
"must be privileged to use -u\n");
exit(ERROR_EXIT);
}
if ((struct passwd *)NULL == getpwnam(optarg))
{
fprintf(stderr, "%s: user `%s' unknown\n",
ProgramName, optarg);
exit(ERROR_EXIT);
}
(void) strcpy(User, optarg);
break;
case 'l':
if (Option != opt_unknown)
usage();
Option = opt_list;
break;
case 'd':
if (Option != opt_unknown)
usage();
Option = opt_delete;
break;
case 'e':
if (Option != opt_unknown)
usage();
Option = opt_edit;
break;
case 'r':
if (Option != opt_unknown)
usage();
Option = opt_replace;
(void) strcpy(Filename, optarg);
break;
default:
usage();
}
}
endpwent();
if (Option == opt_unknown || argv[optind] != NULL)
usage();
if (Option == opt_replace) {
if (!Filename[0]) {
/* getopt(3) says this can't be true
* but I'm feeling extra paranoid today.
*/
fprintf(stderr, "filename must be given for -r\n");
usage();
}
/* we have to open the file here because we're going to
* chdir(2) into /var/cron before we get around to
* reading the file.
*/
if (!strcmp(Filename, "-")) {
NewCrontab = stdin;
} else {
if (!(NewCrontab = fopen(Filename, "r"))) {
perror(Filename);
exit(ERROR_EXIT);
}
}
}
Debug(DMISC, ("user=%s, file=%s, option=%s\n",
User, Filename, Options[(int)Option]))
}
static void
list_cmd()
{
char n[MAX_FNAME];
FILE *f;
int ch;
log_it(RealUser, Pid, "LIST", User);
(void) sprintf(n, CRON_TAB(User));
if (!(f = fopen(n, "r")))
{
if (errno == ENOENT)
fprintf(stderr, "no crontab for %s\n", User);
else
perror(n);
exit(ERROR_EXIT);
}
/* file is open. copy to stdout, close.
*/
Set_LineNum(1)
while (EOF != (ch = get_char(f)))
putchar(ch);
fclose(f);
}
static void
delete_cmd()
{
extern errno;
int unlink();
void poke_daemon();
char n[MAX_FNAME];
log_it(RealUser, Pid, "DELETE", User);
(void) sprintf(n, CRON_TAB(User));
if (unlink(n))
{
if (errno == ENOENT)
fprintf(stderr, "no crontab for %s\n", User);
else
perror(n);
exit(ERROR_EXIT);
}
poke_daemon();
}
static void
check_error(msg)
char *msg;
{
CheckErrorCount += 1;
fprintf(stderr, "\"%s\", line %d: %s\n", Filename, LineNumber, msg);
}
static void
edit_cmd()
{
char n[MAX_FNAME], tn[MAX_FNAME], *editor;
FILE *f, *tf;
int ch, t, pid;
struct stat before, after;
log_it(RealUser, Pid, "BEGIN EDIT", User);
(void) sprintf(n, CRON_TAB(User));
if (!(f = fopen(n, "r")))
{
if (errno == ENOENT)
fprintf(stderr, "no crontab for %s\n", User);
else
perror(n);
exit(ERROR_EXIT);
}
(void) sprintf(tn, "/tmp/crontab.%d", getpid());
if (-1 == (t = open(tn, O_CREAT|O_RDWR, 0600))) {
perror(tn);
exit(ERROR_EXIT);
}
if (fchown(t, getuid(), -1) < OK)
{
perror("chown");
goto fatal;
}
if (!(tf = fdopen(t, "r+"))) {
perror("fdopen");
goto fatal;
}
/* copy the crontab to the temp file. skip top two comments since we
* added them during the 'replace'.
*/
Set_LineNum(1)
t = 0;
while (EOF != (ch = get_char(f))) {
if (t < 2) {
t += (ch == '\n');
} else {
putc(ch, tf);
}
}
fflush(tf); rewind(tf);
fclose(f);
if (ferror(tf)) {
fprintf(stderr, "%s: error while writing new crontab to %s\n",
ProgramName, tn);
fclose(tf);
fatal:
unlink(tn);
exit(ERROR_EXIT);
}
if ((!(editor = getenv("VISUAL")))
&& (!(editor = getenv("EDITOR")))
) {
editor = EDITOR;
}
(void) fstat(fileno(tf), &before);
fclose(tf);
pid = VFORK();
if (pid < 0) {
perror("fork");
goto fatal;
}
if (pid == 0) {
extern char **environ;
char *argv[3];
/* CHILD */
setuid(getuid()); /* give up euid which is root */
argv[0] = editor;
argv[1] = tn;
argv[2] = NULL;
fprintf(stderr, "[%s %s]\n", editor, tn);
execve(editor, argv, environ);
perror(editor);
exit(ERROR_EXIT);
}
(void) wait((int *)0);
if (!(tf = fopen(tn, "r"))) {
perror(tn);
goto fatal;
}
(void) fstat(fileno(tf), &after);
if (after.st_mtime == before.st_mtime) {
fprintf(stderr, "[no changes were made to the crontab]\n");
fclose(tf);
} else {
fprintf(stderr, "[new crontab now being installed]\n");
NewCrontab = tf;
replace_cmd(); /* closes NewCrontab */
}
unlink(tn);
}
static void
replace_cmd()
{
entry *load_entry();
int load_env();
int unlink();
void free_entry();
void check_error();
void poke_daemon();
extern errno;
char n[MAX_FNAME], envstr[MAX_ENVSTR], tn[MAX_FNAME];
FILE *tmp;
int ch;
entry *e;
int status;
time_t now = time(NULL);
(void) sprintf(n, "tmp.%d", Pid);
(void) sprintf(tn, CRON_TAB(n));
if (!(tmp = fopen(tn, "w"))) {
perror(tn);
exit(ERROR_EXIT);
}
/* write a signature at the top of the file. for brian.
*/
fprintf(tmp, "# (%s installed on %-24.24s)\n", Filename, ctime(&now));
fprintf(tmp, "# (Cron version -- %s)\n", rcsid);
/* copy the crontab to the tmp
*/
Set_LineNum(1)
while (EOF != (ch = get_char(NewCrontab)))
putc(ch, tmp);
fclose(NewCrontab);
fflush(tmp); rewind(tmp);
if (ferror(tmp)) {
fprintf(stderr, "%s: error while writing new crontab to %s\n",
ProgramName, tn);
fclose(tmp); unlink(tn);
exit(ERROR_EXIT);
}
/* check the syntax of the file being installed.
*/
/* BUG: was reporting errors after the EOF if there were any errors
* in the file proper -- kludged it by stopping after first error.
* vix 31mar87
*/
CheckErrorCount = 0;
while (!CheckErrorCount && (status = load_env(envstr, tmp)) >= OK)
{
if (status == FALSE)
{
if (NULL != (e = load_entry(NewCrontab, check_error)))
free((char *) e);
}
}
if (CheckErrorCount != 0)
{
fprintf(stderr, "errors in crontab file, can't install.\n");
fclose(tmp); unlink(tn);
exit(ERROR_EXIT);
}
if (fchown(fileno(tmp), ROOT_UID, -1) < OK)
{
perror("chown");
fclose(tmp); unlink(tn);
exit(ERROR_EXIT);
}
if (fchmod(fileno(tmp), 0600) < OK)
{
perror("chown");
fclose(tmp); unlink(tn);
exit(ERROR_EXIT);
}
if (fclose(tmp) == EOF) {
perror("fclose");
unlink(tn);
exit(ERROR_EXIT);
}
(void) sprintf(n, CRON_TAB(User));
if (rename(tn, n))
{
fprintf(stderr, "%s: error renaming %s to %s\n",
ProgramName, tn, n);
perror("rename");
unlink(tn);
exit(ERROR_EXIT);
}
log_it(RealUser, Pid, "REPLACE", User);
poke_daemon();
}
static void
poke_daemon()
{
#if defined(BSD)
struct timeval tvs[2];
struct timezone tz;
(void) gettimeofday(&tvs[0], &tz);
tvs[1] = tvs[0];
if (utimes(SPOOL_DIR, tvs) < OK)
{
fprintf(stderr, "crontab: can't update mtime on spooldir\n");
perror(SPOOL_DIR);
return;
}
#endif /*BSD*/
#if defined(ATT)
if (utime(SPOOL_DIR, NULL) < OK)
{
fprintf(stderr, "crontab: can't update mtime on spooldir\n");
perror(SPOOL_DIR);
return;
}
#endif /*ATT*/
}