/*

 * Written by Cristian Gafton <gafton@redhat.com>

 */

#include "config.h"

#include <assert.h>

#include <ctype.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <sys/types.h>

#include <security/pam_appl.h>

#include <security/pam_misc.h>

#include <pwd.h>

#include <getopt.h>

char *username = NULL;		/* username we are changing the password for */

char *password = NULL;		/* password we are changing the password to */

/* a dummy coversation function */

static int

dummy_conv(int num_msg,

	   const struct pam_message **msg,

	   struct pam_response **resp, void *appdata_ptr)

{

	int i;

	struct pam_response *response = NULL;

	(void)appdata_ptr;

	response = malloc(sizeof(struct pam_response) * num_msg);

	if (response == (struct pam_response *) 0)

		return PAM_CONV_ERR;

	for (i = 0; i < num_msg; i++) {

		response[i].resp_retcode = PAM_SUCCESS;

		switch (msg[i]->msg_style) {

		case PAM_PROMPT_ECHO_ON:

			response[i].resp = username;

			break;

		case PAM_PROMPT_ECHO_OFF:

			response[i].resp = password;

			break;

		case PAM_TEXT_INFO:

		case PAM_ERROR_MSG:

			/* ignore it, but pam still wants a NULL response... */

			response[i].resp = NULL;

			break;

		default:

			/* Must be an error of some sort... */

			free(response);

			return PAM_CONV_ERR;

		}

	}

	*resp = response;

	return PAM_SUCCESS;

}

/* conversation function & corresponding structure */

static struct pam_conv conv = {

	&dummy_conv,

	NULL

};

int

main(int argc, char *const argv[])

{

	int retval;

	pam_handle_t *pamh = NULL;

	/* XXX; expand me:

	 *

	 * here you should obtains somehow the username and password and

	 * set the global variables

	 */

	(void)argc;

	(void)argv;

	assert(username != NULL);

	assert(password != NULL);

	retval = pam_start("passwd", username, &conv, &pamh);

	while (retval == PAM_SUCCESS) {	/* use loop to avoid goto... */

		retval = pam_chauthtok(pamh, 0);

		if (retval != PAM_SUCCESS)

			break;

		/* all done */

		retval = pam_end(pamh, PAM_SUCCESS);

		if (retval != PAM_SUCCESS)

			break;

		/* quit gracefully */

		exit(0);

	}

	if (retval != PAM_SUCCESS)

		fprintf(stderr, "changing password: %s\n",

			pam_strerror(pamh, retval));

	if (pamh != NULL) {

		(void) pam_end(pamh, PAM_SUCCESS);

		pamh = NULL;

	}

	exit(1);

}