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/* $OpenBSD: skeyaudit.c,v 1.13 2002/05/16 03:50:42 millert Exp $ */
/*
* Copyright (c) 1997, 2000 Todd C. Miller <Todd.Miller@courtesan.com>
* 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.
*
* 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.
*/
#include <sys/param.h>
#include <sys/wait.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <login_cap.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <skey.h>
extern char *__progname;
void notify(struct passwd *, int, int);
FILE *runsendmail(struct passwd *, int *);
void usage(void);
int
main(argc, argv)
int argc;
char **argv;
{
struct passwd *pw;
struct skey key;
int ch, errs = 0, left = 0, aflag = 0, iflag = 0, limit = 12;
char *name;
while ((ch = getopt(argc, argv, "ail:")) != -1)
switch(ch) {
case 'a':
aflag = 1;
if (getuid() != 0)
errx(1, "only root may use the -a flag");
break;
case 'i':
iflag = 1;
break;
case 'l':
errno = 0;
if ((limit = (int)strtol(optarg, NULL, 10)) == 0)
errno = ERANGE;
if (errno) {
warn("key limit");
usage();
}
break;
default:
usage();
}
if (argc - optind > 0)
usage();
/* Need key.keyfile zero'd at the very least */
(void)memset(&key, 0, sizeof(key));
if (aflag) {
while ((ch = skeygetnext(&key)) == 0) {
left = key.n - 1;
if ((pw = getpwnam(key.logname)) == NULL)
continue;
if (left >= limit)
continue;
notify(pw, left, iflag);
}
if (ch == -1)
errx(-1, "cannot open %s", _PATH_SKEYDIR);
else
(void)fclose(key.keyfile);
} else {
if ((pw = getpwuid(getuid())) == NULL)
errx(1, "no passwd entry for uid %u", getuid());
if ((name = strdup(pw->pw_name)) == NULL)
err(1, "cannot allocate memory");
sevenbit(name);
errs = skeylookup(&key, name);
switch (errs) {
case 0: /* Success! */
left = key.n - 1;
break;
case -1: /* File error */
errx(errs, "cannot open %s", _PATH_SKEYDIR);
break;
case 1: /* Unknown user */
warnx("%s is not listed in %s", name,
_PATH_SKEYDIR);
}
(void)fclose(key.keyfile);
if (!errs && left < limit)
notify(pw, left, iflag);
}
exit(errs);
}
void
notify(pw, seq, interactive)
struct passwd *pw;
int seq;
int interactive;
{
static char hostname[MAXHOSTNAMELEN];
int pid;
FILE *out;
/* Only set this once */
if (hostname[0] == '\0' && gethostname(hostname, sizeof(hostname)) == -1)
strcpy(hostname, "unknown");
if (interactive)
out = stdout;
else
out = runsendmail(pw, &pid);
if (!interactive)
(void)fprintf(out,
"To: %s\nSubject: IMPORTANT action required\n", pw->pw_name);
if (seq)
(void)fprintf(out,
"\nYou are nearing the end of your current S/Key sequence for account\n\
%s on system %s.\n\n\
Your S/Key sequence number is now %d. When it reaches zero\n\
you will no longer be able to use S/Key to log into the system.\n\n",
pw->pw_name, hostname, seq);
else
(void)fprintf(out,
"\nYou are at the end of your current S/Key sequence for account\n\
%s on system %s.\n\n\
At this point you can no longer use S/Key to log into the system.\n\n",
pw->pw_name, hostname);
(void)fprintf(out,
"Type \"skeyinit -s\" to reinitialize your sequence number.\n\n");
(void)fclose(out);
if (!interactive)
(void)waitpid(pid, NULL, 0);
}
FILE *
runsendmail(pw, pidp)
struct passwd *pw;
int *pidp;
{
FILE *fp;
int pfd[2], pid;
if (pipe(pfd) < 0)
return(NULL);
switch (pid = fork()) {
case -1: /* fork(2) failed */
(void)close(pfd[0]);
(void)close(pfd[1]);
return(NULL);
case 0: /* In child */
(void)close(pfd[1]);
(void)dup2(pfd[0], STDIN_FILENO);
(void)close(pfd[0]);
/* Run sendmail as target user not root */
if (setusercontext(NULL, pw, pw->pw_uid, LOGIN_SETALL) != 0) {
warn("cannot set user context");
_exit(127);
}
execl(_PATH_SENDMAIL, "sendmail", "-t", (char *)NULL);
warn("cannot run \"%s -t\"", _PATH_SENDMAIL);
_exit(127);
}
/* In parent */
*pidp = pid;
fp = fdopen(pfd[1], "w");
(void)close(pfd[0]);
return(fp);
}
void
usage()
{
(void)fprintf(stderr, "Usage: %s [-i] [-l limit]\n",
__progname);
exit(1);
}
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