NetBSD-5.0.2/usr.sbin/timed/timedc/timedc.c
/* $NetBSD: timedc.c,v 1.21 2008/07/21 13:37:00 lukem Exp $ */
/*-
* Copyright (c) 1985, 1993 The Regents of the University of California.
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1985, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)timedc.c 8.1 (Berkeley) 6/6/93";
#else
__RCSID("$NetBSD: timedc.c,v 1.21 2008/07/21 13:37:00 lukem Exp $");
#endif
#endif /* not lint */
#include "timedc.h"
#include <ctype.h>
#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <fcntl.h>
#include <pwd.h>
#include <err.h>
int trace = 0;
FILE *fd = 0;
int margc;
int fromatty;
#define MAX_MARGV 20
char *margv[MAX_MARGV];
char cmdline[200];
jmp_buf toplevel;
static const struct cmd *getcmd(char *);
static int drop_privileges(void);
int
main(int argc, char *argv[])
{
const struct cmd *c;
fcntl(3, F_CLOSEM);
openlog("timedc", 0, LOG_AUTH);
/*
* security dictates!
*/
if (priv_resources() < 0)
errx(EXIT_FAILURE, "Could not get privileged resources");
if (drop_privileges() < 0)
errx(EXIT_FAILURE, "Could not drop privileges");
if (--argc > 0) {
c = getcmd(*++argv);
if (c == (struct cmd *)-1) {
printf("?Ambiguous command\n");
exit(EXIT_FAILURE);
}
if (c == 0) {
printf("?Invalid command\n");
exit(EXIT_FAILURE);
}
(*c->c_handler)(argc, argv);
exit(EXIT_SUCCESS);
}
fromatty = isatty(fileno(stdin));
if (setjmp(toplevel))
putchar('\n');
(void) signal(SIGINT, intr);
for (;;) {
if (fromatty) {
printf("timedc> ");
(void) fflush(stdout);
}
if (fgets(cmdline, sizeof(cmdline), stdin) == 0)
quit(0, NULL);
if (cmdline[0] == 0)
break;
if (makeargv()) {
printf("?Too many arguments\n");
continue;
}
if (margv[0] == 0)
continue;
c = getcmd(margv[0]);
if (c == (struct cmd *)-1) {
printf("?Ambiguous command\n");
continue;
}
if (c == 0) {
printf("?Invalid command\n");
continue;
}
(*c->c_handler)(margc, margv);
}
return 0;
}
void
intr(int signo)
{
(void) signo;
if (!fromatty)
exit(EXIT_SUCCESS);
longjmp(toplevel, 1);
}
static const struct cmd *
getcmd(char *name)
{
const char *p;
char *q;
const struct cmd *c, *found;
int nmatches, longest;
extern const struct cmd cmdtab[];
extern int NCMDS;
longest = 0;
nmatches = 0;
found = 0;
for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
p = c->c_name;
for (q = name; *q == *p++; q++)
if (*q == 0) /* exact match? */
return(c);
if (!*q) { /* the name was a prefix */
if (q - name > longest) {
longest = q - name;
nmatches = 1;
found = c;
} else if (q - name == longest)
nmatches++;
}
}
if (nmatches > 1)
return((struct cmd *)-1);
return(found);
}
/*
* Slice a string up into argc/argv.
*/
int
makeargv(void)
{
char *cp;
char **argp = margv;
margc = 0;
for (cp = cmdline; argp < &margv[MAX_MARGV - 1] && *cp;) {
while (isspace((unsigned char)*cp))
cp++;
if (*cp == '\0')
break;
*argp++ = cp;
margc += 1;
while (*cp != '\0' && !isspace((unsigned char)*cp))
cp++;
if (*cp == '\0')
break;
*cp++ = '\0';
}
if (margc == MAX_MARGV - 1)
return 1;
*argp++ = 0;
return 0;
}
#define HELPINDENT (sizeof ("directory"))
/*
* Help command.
*/
void
help(int argc, char *argv[])
{
const struct cmd *c;
extern const struct cmd cmdtab[];
if (argc == 1) {
int i, j, w;
int columns, width = 0, lines;
extern int NCMDS;
printf("Commands may be abbreviated. Commands are:\n\n");
for (c = cmdtab; c < &cmdtab[NCMDS]; c++) {
int len = strlen(c->c_name);
if (len > width)
width = len;
}
width = (width + 8) &~ 7;
columns = 80 / width;
if (columns == 0)
columns = 1;
lines = (NCMDS + columns - 1) / columns;
for (i = 0; i < lines; i++) {
for (j = 0; j < columns; j++) {
c = cmdtab + j * lines + i;
printf("%s", c->c_name);
if (c + lines >= &cmdtab[NCMDS]) {
printf("\n");
break;
}
w = strlen(c->c_name);
while (w < width) {
w = (w + 8) &~ 7;
putchar('\t');
}
}
}
return;
}
while (--argc > 0) {
char *arg;
arg = *++argv;
c = getcmd(arg);
if (c == (struct cmd *)-1)
printf("?Ambiguous help command %s\n", arg);
else if (c == (struct cmd *)0)
printf("?Invalid help command %s\n", arg);
else
printf("%-*s\t%s\n", (int)HELPINDENT,
c->c_name, c->c_help);
}
}
static int
drop_privileges(void)
{
static const char user[] = "_timedc";
const struct passwd *pw;
uid_t uid;
gid_t gid;
if ((pw = getpwnam(user)) == NULL) {
warnx("getpwnam(\"%s\") failed", user);
return -1;
}
uid = pw->pw_uid;
gid = pw->pw_gid;
if (setgroups(1, &gid)) {
warn("setgroups");
return -1;
}
if (setgid(gid)) {
warn("setgid");
return -1;
}
if (setuid(uid)) {
warn("setuid");
return -1;
}
return 0;
}