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/* pam_nologin module */
/*
* $Id$
*
* Written by Michael K. Johnson <johnsonm@redhat.com> 1996/10/24
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <pwd.h>
#include <security/_pam_macros.h>
/*
* here, we make a definition for the externally accessible function
* in this file (this definition is required for static a module
* but strongly encouraged generally) it is used to instruct the
* modules include file to define the function prototypes.
*/
#define PAM_SM_AUTH
#include <security/pam_modules.h>
/* --- authentication management functions (only) --- */
PAM_EXTERN
int pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc,
const char **argv)
{
int retval = PAM_SUCCESS;
int fd;
const char *username;
char *mtmp=NULL;
struct passwd *user_pwd;
struct pam_conv *conversation;
struct pam_message message;
struct pam_message *pmessage = &message;
struct pam_response *resp = NULL;
struct stat st;
if ((fd = open("/etc/nologin", O_RDONLY, 0)) >= 0) {
/* root can still log in; lusers cannot */
if ((pam_get_user(pamh, &username, NULL) != PAM_SUCCESS)
|| !username) {
return PAM_SERVICE_ERR;
}
user_pwd = getpwnam(username);
if (user_pwd && user_pwd->pw_uid == 0) {
message.msg_style = PAM_TEXT_INFO;
} else {
if (!user_pwd) {
retval = PAM_USER_UNKNOWN;
} else {
retval = PAM_AUTH_ERR;
}
message.msg_style = PAM_ERROR_MSG;
}
/* fill in message buffer with contents of /etc/nologin */
if (fstat(fd, &st) < 0) /* give up trying to display message */
return retval;
message.msg = mtmp = malloc(st.st_size+1);
/* if malloc failed... */
if (!message.msg) return retval;
read(fd, mtmp, st.st_size);
mtmp[st.st_size] = '\000';
/* Use conversation function to give user contents of /etc/nologin */
pam_get_item(pamh, PAM_CONV, (const void **)&conversation);
conversation->conv(1, (const struct pam_message **)&pmessage,
&resp, conversation->appdata_ptr);
free(mtmp);
if (resp)
_pam_drop_reply(resp, 1);
}
return retval;
}
PAM_EXTERN
int pam_sm_setcred(pam_handle_t *pamh, int flags, int argc,
const char **argv)
{
return PAM_SUCCESS;
}
#ifdef PAM_STATIC
/* static module data */
struct pam_module _pam_nologin_modstruct = {
"pam_nologin",
pam_sm_authenticate,
pam_sm_setcred,
NULL,
NULL,
NULL,
NULL,
};
#endif
/* end of module definition */
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