d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
56dcbac924
freebsd-nq/usr.bin/at/at.c

563 lines
12 KiB
C
Raw Blame History

/*
* at.c : Put file into atrun queue
* Copyright (C) 1993 Thomas Koenig
*
* Atrun & Atq modifications
* Copyright (C) 1993 David Parsons
* 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. The name of the author(s) may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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, WETHER 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.
*/
#define _USE_BSD 1
/* System Headers */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <signal.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
/* Local headers */
#include "at.h"
#include "panic.h"
#include "parsetime.h"
#include "pathnames.h"
#define MAIN
#include "privs.h"
/* Macros */
#define ALARMC 10 /* Number of seconds to wait for timeout */
#define SIZE 255
#define TIMESIZE 50
/* File scope variables */
static char rcsid[] = "$Id: at.c,v 1.2 1993/12/06 04:10:42 cgd Exp $";
char *no_export[] =
{
"TERM", "TERMCAP", "DISPLAY", "_"
};
static send_mail = 0;
/* External variables */
extern char **environ;
int fcreated;
char *namep;
char atfile[FILENAME_MAX];
char *atinput = (char *) 0; /* where to get input from */
char atqueue = 0; /* which queue to examine for jobs (atq) */
char atverify = 0; /* verify time instead of queuing job */
/* Function declarations */
static void sigc __P((int signo));
static void alarmc __P((int signo));
static char *cwdname __P((void));
static void writefile __P((time_t runtimer, char queue));
static void list_jobs __P((void));
/* Signal catching functions */
static void
sigc(signo)
int signo;
{
/* If the user presses ^C, remove the spool file and exit
*/
if (fcreated) {
PRIV_START
unlink(atfile);
PRIV_END
}
exit(EXIT_FAILURE);
}
static void
alarmc(signo)
int signo;
{
/* Time out after some seconds
*/
panic("File locking timed out");
}
/* Local functions */
static char *
cwdname()
{
/* Read in the current directory; the name will be overwritten on
* subsequent calls.
*/
static char *ptr = NULL;
static size_t size = SIZE;
if (ptr == NULL)
ptr = (char *) malloc(size);
while (1) {
if (ptr == NULL)
panic("Out of memory");
if (getcwd(ptr, size - 1) != NULL)
return ptr;
if (errno != ERANGE)
perr("Cannot get directory");
free(ptr);
size += SIZE;
ptr = (char *) malloc(size);
}
}
static void
writefile(runtimer, queue)
time_t runtimer;
char queue;
{
/*
* This does most of the work if at or batch are invoked for
* writing a job.
*/
int i;
char *ap, *ppos, *mailname;
struct passwd *pass_entry;
struct stat statbuf;
int fdes, lockdes, fd2;
FILE *fp, *fpin;
struct sigaction act;
char **atenv;
int ch;
mode_t cmask;
struct flock lock;
/*
* Install the signal handler for SIGINT; terminate after removing the
* spool file if necessary
*/
act.sa_handler = sigc;
sigemptyset(&(act.sa_mask));
act.sa_flags = 0;
sigaction(SIGINT, &act, NULL);
strcpy(atfile, _PATH_ATJOBS);
ppos = atfile + strlen(_PATH_ATJOBS);
/*
* Loop over all possible file names for running something at this
* particular time, see if a file is there; the first empty slot at
* any particular time is used. Lock the file _PATH_LOCKFILE first
* to make sure we're alone when doing this.
*/
PRIV_START
if ((lockdes = open(_PATH_LOCKFILE, O_WRONLY | O_CREAT, 0600)) < 0)
perr2("Cannot open lockfile ", _PATH_LOCKFILE);
lock.l_type = F_WRLCK;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0;
act.sa_handler = alarmc;
sigemptyset(&(act.sa_mask));
act.sa_flags = 0;
/*
* Set an alarm so a timeout occurs after ALARMC seconds, in case
* something is seriously broken.
*/
sigaction(SIGALRM, &act, NULL);
alarm(ALARMC);
fcntl(lockdes, F_SETLKW, &lock);
alarm(0);
for (i = 0; i < AT_MAXJOBS; i++) {
sprintf(ppos, "%c%8lx.%3x", queue,
(unsigned long) (runtimer / 60), i);
for (ap = ppos; *ap != '\0'; ap++)
if (*ap == ' ')
*ap = '0';
if (stat(atfile, &statbuf) != 0) {
if (errno == ENOENT)
break;
else
perr2("Cannot access ", _PATH_ATJOBS);
}
} /* for */
if (i >= AT_MAXJOBS)
panic("Too many jobs already");
/*
* Create the file. The x bit is only going to be set after it has
* been completely written out, to make sure it is not executed in
* the meantime. To make sure they do not get deleted, turn off
* their r bit. Yes, this is a kluge.
*/
cmask = umask(S_IRUSR | S_IWUSR | S_IXUSR);
if ((fdes = creat(atfile, O_WRONLY)) == -1)
perr("Cannot create atjob file");
if ((fd2 = dup(fdes)) < 0)
perr("Error in dup() of job file");
if (fchown(fd2, real_uid, -1) != 0)
perr("Cannot give away file");
PRIV_END
/*
* We no longer need suid root; now we just need to be able to
* write to the directory, if necessary.
*/
REDUCE_PRIV(0);
/*
* We've successfully created the file; let's set the flag so it
* gets removed in case of an interrupt or error.
*/
fcreated = 1;
/* Now we can release the lock, so other people can access it */
lock.l_type = F_UNLCK;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0;
fcntl(lockdes, F_SETLKW, &lock);
close(lockdes);
if ((fp = fdopen(fdes, "w")) == NULL)
panic("Cannot reopen atjob file");
/*
* Get the userid to mail to, first by trying getlogin(), which
* reads /etc/utmp, then from LOGNAME, finally from getpwuid().
*/
mailname = getlogin();
if (mailname == NULL)
mailname = getenv("LOGNAME");
if ((mailname == NULL) || (mailname[0] == '\0')
|| (strlen(mailname) > 8)) {
pass_entry = getpwuid(getuid());
if (pass_entry != NULL)
mailname = pass_entry->pw_name;
}
if (atinput != (char *) NULL) {
fpin = freopen(atinput, "r", stdin);
if (fpin == NULL)
perr("Cannot open input file");
}
fprintf(fp, "#! /bin/sh\n# mail %8s %d\n", mailname, send_mail);
/* Write out the umask at the time of invocation */
fprintf(fp, "umask %lo\n", (unsigned long) cmask);
/*
* Write out the environment. Anything that may look like a special
* character to the shell is quoted, except for \n, which is done
* with a pair of "'s. Dont't export the no_export list (such as
* TERM or DISPLAY) because we don't want these.
*/
for (atenv = environ; *atenv != NULL; atenv++) {
int export = 1;
char *eqp;
eqp = strchr(*atenv, '=');
if (ap == NULL)
eqp = *atenv;
else {
int i;
for (i = 0;i < sizeof(no_export) /
sizeof(no_export[0]); i++) {
export = export
&& (strncmp(*atenv, no_export[i],
(size_t) (eqp - *atenv)) != 0);
}
eqp++;
}
if (export) {
fwrite(*atenv, sizeof(char), eqp - *atenv, fp);
for (ap = eqp; *ap != '\0'; ap++) {
if (*ap == '\n')
fprintf(fp, "\"\n\"");
else {
if (!isalnum(*ap))
fputc('\\', fp);
fputc(*ap, fp);
}
}
fputs("; export ", fp);
fwrite(*atenv, sizeof(char), eqp - *atenv - 1, fp);
fputc('\n', fp);
}
}
/*
* Cd to the directory at the time and write out all the commands
* the user supplies from stdin.
*/
fprintf(fp, "cd %s\n", cwdname());
while ((ch = getchar()) != EOF)
fputc(ch, fp);
fprintf(fp, "\n");
if (ferror(fp))
panic("Output error");
if (ferror(stdin))
panic("Input error");
fclose(fp);
/*
* Set the x bit so that we're ready to start executing
*/
if (fchmod(fd2, S_IRUSR | S_IWUSR | S_IXUSR) < 0)
perr("Cannot give away file");
close(fd2);
fprintf(stderr, "Job %s will be executed using /bin/sh\n", ppos);
}
static void
list_jobs()
{
/*
* List all a user's jobs in the queue, by looping through
* _PATH_ATJOBS, or everybody's if we are root
*/
struct passwd *pw;
DIR *spool;
struct dirent *dirent;
struct stat buf;
struct tm runtime;
unsigned long ctm;
char queue;
time_t runtimer;
char timestr[TIMESIZE];
int first = 1;
PRIV_START
if (chdir(_PATH_ATJOBS) != 0)
perr2("Cannot change to ", _PATH_ATJOBS);
if ((spool = opendir(".")) == NULL)
perr2("Cannot open ", _PATH_ATJOBS);
/* Loop over every file in the directory */
while ((dirent = readdir(spool)) != NULL) {
if (stat(dirent->d_name, &buf) != 0)
perr2("Cannot stat in ", _PATH_ATJOBS);
/*
* See it's a regular file and has its x bit turned on and
* is the user's
*/
if (!S_ISREG(buf.st_mode)
|| ((buf.st_uid != real_uid) && !(real_uid == 0))
|| !(S_IXUSR & buf.st_mode || atverify))
continue;
if (sscanf(dirent->d_name, "%c%8lx", &queue, &ctm) != 2)
continue;
if (atqueue && (queue != atqueue))
continue;
runtimer = 60 * (time_t) ctm;
runtime = *localtime(&runtimer);
strftime(timestr, TIMESIZE, "%X %x", &runtime);
if (first) {
printf("Date\t\t\tOwner\tQueue\tJob#\n");
first = 0;
}
pw = getpwuid(buf.st_uid);
printf("%s\t%s\t%c%s\t%s\n",
timestr,
pw ? pw->pw_name : "???",
queue,
(S_IXUSR & buf.st_mode) ? "" : "(done)",
dirent->d_name);
}
PRIV_END
}
static void
delete_jobs(argc, argv)
int argc;
char **argv;
{
/* Delete every argument (job - ID) given */
int i;
struct stat buf;
PRIV_START
if (chdir(_PATH_ATJOBS) != 0)
perr2("Cannot change to ", _PATH_ATJOBS);
for (i = optind; i < argc; i++) {
if (stat(argv[i], &buf) != 0)
perr(argv[i]);
if ((buf.st_uid != real_uid) && !(real_uid == 0)) {
fprintf(stderr, "%s: Not owner\n", argv[i]);
exit(EXIT_FAILURE);
}
if (unlink(argv[i]) != 0)
perr(argv[i]);
}
PRIV_END
} /* delete_jobs */
/* Global functions */
int
main(argc, argv)
int argc;
char **argv;
{
int c;
char queue = 'a';
char *pgm;
enum {
ATQ, ATRM, AT, BATCH
}; /* what program we want to run */
int program = AT; /* our default program */
char *options = "q:f:mv"; /* default options for at */
time_t timer;
RELINQUISH_PRIVS
/* Eat any leading paths */
if ((pgm = strrchr(argv[0], '/')) == NULL)
pgm = argv[0];
else
pgm++;
namep = pgm;
/* find out what this program is supposed to do */
if (strcmp(pgm, "atq") == 0) {
program = ATQ;
options = "q:v";
} else if (strcmp(pgm, "atrm") == 0) {
program = ATRM;
options = "";
} else if (strcmp(pgm, "batch") == 0) {
program = BATCH;
options = "f:mv";
}
/* process whatever options we can process */
opterr = 1;
while ((c = getopt(argc, argv, options)) != EOF)
switch (c) {
case 'v': /* verify time settings */
atverify = 1;
break;
case 'm': /* send mail when job is complete */
send_mail = 1;
break;
case 'f':
atinput = optarg;
break;
case 'q': /* specify queue */
if (strlen(optarg) > 1)
usage();
atqueue = queue = *optarg;
if ((!islower(queue)) || (queue > 'l'))
usage();
break;
default:
usage();
break;
}
/* end of options eating */
/* select our program */
switch (program) {
case ATQ:
REDUCE_PRIV(0);
list_jobs();
break;
case ATRM:
REDUCE_PRIV(0);
delete_jobs(argc, argv);
break;
case AT:
timer = parsetime(argc, argv);
if (atverify) {
struct tm *tm = localtime(&timer);
fprintf(stderr, "%s\n", asctime(tm));
}
writefile(timer, queue);
break;
case BATCH:
writefile(time(NULL), 'b');
break;
default:
panic("Internal error");
break;
}
exit(EXIT_SUCCESS);
}
Reference in New Issue View Git Blame Copy Permalink