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#define _XOPEN_SOURCE 700
#include <errno.h>
#include <grp.h>
#include <locale.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <pwd.h>
#include <unistd.h>
#include "check.h"
static char *progname = NULL;
void fatal(int include_errno, char *fmt, ...)
{
fprintf(stderr, "%s: ", progname);
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
if (include_errno) {
fprintf(stderr, ": %s", strerror(errno));
}
fputc('\n', stderr);
exit(EXIT_FAILURE);
}
static char *get_username(void)
{
struct passwd *pwd = getpwuid(getuid());
if (pwd == NULL) {
fatal(1, "unable to determine user name");
}
return pwd->pw_name;
}
static char *get_groupname(void)
{
struct group *grp = getgrgid(getgid());
if (grp == NULL) {
fatal(1, "unable to determine group name");
}
return grp->gr_name;
}
static char *get_command(int argc, char *argv[])
{
if (argc < 2) {
fatal(1, "missing operands");
}
return argv[1];
}
int main(int argc, char *argv[])
{
setlocale(LC_ALL, "");
progname = argv[0];
char *cmd = get_command(argc, argv);
char *user = get_username();
char *group = get_groupname();
openlog(PRIVEXEC_LOG_ID, LOG_PID, LOG_AUTH);
syslog(LOG_INFO, "checking %s:%s for permission to run %s",
user, group, cmd);
switch (get_permission(user, group, cmd)) {
case AUTH_GROUP_ALL:
case AUTH_GROUP_CMD:
case AUTH_USER_ALL:
case AUTH_USER_CMD:
syslog(LOG_INFO, "%s:%s requires authentication to run %s",
user, group, cmd);
if (authenticate(user) != 0) {
syslog(LOG_NOTICE, "%s:%s failed authentication for %s",
user, group, cmd);
fatal(0, "bad authentication");
}
/* FALLTHRU */
case PASS_GROUP_ALL:
case PASS_GROUP_CMD:
case PASS_USER_ALL:
case PASS_USER_CMD:
syslog(LOG_INFO, "%s:%s authorized to run %s",
user, group, cmd);
return 0;
case DENY_GROUP_ALL:
case DENY_GROUP_CMD:
case DENY_USER_ALL:
case DENY_USER_CMD:
syslog(LOG_NOTICE,
"%s:%s explicitly denied permission to run %s",
user, group, cmd);
fatal(0, "explicitly denied");
return 1;
case UNKNOWN:
default:
syslog(LOG_NOTICE,
"%s:%s denied permission to run %s by default",
user, group, cmd);
fatal(0, "denied by default");
}
return 1;
}
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