/*      $NetBSD: upap.h,v 1.6 2025/01/08 19:59:39 christos Exp $        */

/*
* upap.h - User/Password Authentication Protocol definitions.
*
* Copyright (c) 1984-2000 Carnegie Mellon University. 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 "Carnegie Mellon University" must not be used to
*    endorse or promote products derived from this software without
*    prior written permission. For permission or any legal
*    details, please contact
*      Office of Technology Transfer
*      Carnegie Mellon University
*      5000 Forbes Avenue
*      Pittsburgh, PA  15213-3890
*      (412) 268-4387, fax: (412) 268-7395
*      [email protected]
*
* 4. Redistributions of any form whatsoever must retain the following
*    acknowledgment:
*    "This product includes software developed by Computing Services
*     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
*
* CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef PPP_UPAP_H
#define PPP_UPAP_H

#include "pppdconf.h"

#ifdef __cplusplus
extern "C" {
#endif


/*
* Packet header = Code, id, length.
*/
#define UPAP_HEADERLEN  4


/*
* UPAP codes.
*/
#define UPAP_AUTHREQ    1       /* Authenticate-Request */
#define UPAP_AUTHACK    2       /* Authenticate-Ack */
#define UPAP_AUTHNAK    3       /* Authenticate-Nak */


/*
* Each interface is described by upap structure.
*/
typedef struct upap_state {
   int us_unit;                /* Interface unit number */
   char *us_user;              /* User */
   int us_userlen;             /* User length */
   char *us_passwd;            /* Password */
   int us_passwdlen;           /* Password length */
   int us_clientstate;         /* Client state */
   int us_serverstate;         /* Server state */
   unsigned char us_id;                /* Current id */
   int us_timeouttime;         /* Timeout (seconds) for auth-req retrans. */
   int us_transmits;           /* Number of auth-reqs sent */
   int us_maxtransmits;        /* Maximum number of auth-reqs to send */
   int us_reqtimeout;          /* Time to wait for auth-req from peer */
} upap_state;


/*
* Client states.
*/
#define UPAPCS_INITIAL  0       /* Connection down */
#define UPAPCS_CLOSED   1       /* Connection up, haven't requested auth */
#define UPAPCS_PENDING  2       /* Connection down, have requested auth */
#define UPAPCS_AUTHREQ  3       /* We've sent an Authenticate-Request */
#define UPAPCS_OPEN     4       /* We've received an Ack */
#define UPAPCS_BADAUTH  5       /* We've received a Nak */

/*
* Server states.
*/
#define UPAPSS_INITIAL  0       /* Connection down */
#define UPAPSS_CLOSED   1       /* Connection up, haven't requested auth */
#define UPAPSS_PENDING  2       /* Connection down, have requested auth */
#define UPAPSS_LISTEN   3       /* Listening for an Authenticate */
#define UPAPSS_OPEN     4       /* We've sent an Ack */
#define UPAPSS_BADAUTH  5       /* We've sent a Nak */


/*
* Timeouts.
*/
#define UPAP_DEFTIMEOUT 3       /* Timeout (seconds) for retransmitting req */
#define UPAP_DEFREQTIME 30      /* Time to wait for auth-req from peer */

extern upap_state upap[];

void upap_authwithpeer(int, char *, char *);
void upap_authpeer(int);

extern struct protent pap_protent;

typedef int  (pap_check_hook_fn)(void);
typedef int  (pap_auth_hook_fn)(char *user, char *passwd, char **msgp,
               struct wordlist **paddrs,
               struct wordlist **popts);
typedef void (pap_logout_hook_fn)(void);
typedef int  (pap_passwd_hook_fn)(char *user, char *passwd);

/*
* This function will return a value of 1 to indicate that a plugin intent to
*   supply a username or a password through the pap_auth_hook callback.
*
* A return value of > 0 will avoid parsing pap-secrets file.
*/
extern pap_check_hook_fn  *pap_check_hook;

/*
* This hook is used to check if a username and password matches against the
*   PAP secrets.
*/
extern pap_auth_hook_fn   *pap_auth_hook;

/*
* Hook for plugin to know about PAP user logout.
*/
extern pap_logout_hook_fn *pap_logout_hook;

/*
* A plugin can chose to supply its own user and password overriding what
* previously has been configured. Hook is only valid when pppd is acting
* as a client
*/
extern pap_passwd_hook_fn *pap_passwd_hook;

#ifdef __cplusplus
}
#endif

#endif // PPP_UPAP_H