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#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <pwd.h>
#define PAM_SM_AUTH
#include <security/pam_appl.h>
#include <security/pam_modules.h>
#include <security/pam_mod_misc.h>
#define NOLOGIN "/etc/nologin"
PAM_EXTERN int
pam_sm_authenticate( pam_handle_t *pamh, int flags,
int argc, const char * argv[] )
{
struct passwd *pwd;
struct stat st;
char *mtmp = NULL;
const char * user;
int pam_err, fd;
if( (pam_err = pam_get_user(pamh,&user, NULL)) != PAM_SUCCESS ||
(user == NULL) ) {
PAM_ERROR("Could not determine user");
return (PAM_USER_UNKNOWN);
}
fd = open(NOLOGIN, O_RDONLY, 0);
/*
* LinuxPAM's nologin returns PAM_IGNORE when no 'nologin' file is
* present while freebsd's nologin returns PAM_SUCCESS. We'll go
* with PAM_IGNORE
* */
if (fd < 0 )
return (PAM_IGNORE);
pwd = getpwnam(user);
if(pwd && pwd->pw_uid == 0 )
pam_err = PAM_SUCCESS;
else {
if ( ! pwd )
pam_err = PAM_USER_UNKNOWN;
else
pam_err = PAM_AUTH_ERR;
}
/* get contents of /etc/nologin */
if (fstat(fd,&st) < 0) {
close(fd);
free(mtmp);
return (pam_err);
}
mtmp = malloc(st.st_size + 1);
if (!mtmp) {
PAM_ERROR("Out of memory");
close(fd);
free(mtmp);
return (PAM_BUF_ERR);
}
if ( read(fd, mtmp, st.st_size) == st.st_size ) {
mtmp[st.st_size] = '\0';
PAM_ERROR("%s", mtmp);
} else
pam_err = PAM_SYSTEM_ERR;
close(fd);
free (mtmp);
return (pam_err);
}
PAM_EXTERN int
pam_sm_setcred(pam_handle_t *pamh , int flags ,
int argc , const char *argv[])
{
return (PAM_SUCCESS);
}
PAM_MODULE_ENTRY("pam_nologin");
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