591 lines
13 KiB
C
591 lines
13 KiB
C
/*
|
|
* upap.c - User/Password Authentication Protocol.
|
|
*
|
|
* Copyright (c) 1989 Carnegie Mellon University.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms are permitted
|
|
* provided that the above copyright notice and this paragraph are
|
|
* duplicated in all such forms and that any documentation,
|
|
* advertising materials, and other materials related to such
|
|
* distribution and use acknowledge that the software was developed
|
|
* by Carnegie Mellon University. The name of the
|
|
* University may not be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char rcsid[] = "$Id: upap.c,v 1.6 1995/06/12 12:02:24 paulus Exp $";
|
|
#endif
|
|
|
|
/*
|
|
* TODO:
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <sys/types.h>
|
|
#include <sys/time.h>
|
|
#include <syslog.h>
|
|
|
|
#include "pppd.h"
|
|
#include "upap.h"
|
|
|
|
|
|
upap_state upap[NUM_PPP]; /* UPAP state; one for each unit */
|
|
|
|
|
|
static void upap_timeout __P((caddr_t));
|
|
static void upap_reqtimeout __P((caddr_t));
|
|
static void upap_rauthreq __P((upap_state *, u_char *, int, int));
|
|
static void upap_rauthack __P((upap_state *, u_char *, int, int));
|
|
static void upap_rauthnak __P((upap_state *, u_char *, int, int));
|
|
static void upap_sauthreq __P((upap_state *));
|
|
static void upap_sresp __P((upap_state *, int, int, char *, int));
|
|
|
|
|
|
/*
|
|
* upap_init - Initialize a UPAP unit.
|
|
*/
|
|
void
|
|
upap_init(unit)
|
|
int unit;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
|
|
u->us_unit = unit;
|
|
u->us_user = NULL;
|
|
u->us_userlen = 0;
|
|
u->us_passwd = NULL;
|
|
u->us_passwdlen = 0;
|
|
u->us_clientstate = UPAPCS_INITIAL;
|
|
u->us_serverstate = UPAPSS_INITIAL;
|
|
u->us_id = 0;
|
|
u->us_timeouttime = UPAP_DEFTIMEOUT;
|
|
u->us_maxtransmits = 10;
|
|
u->us_reqtimeout = UPAP_DEFREQTIME;
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_authwithpeer - Authenticate us with our peer (start client).
|
|
*
|
|
* Set new state and send authenticate's.
|
|
*/
|
|
void
|
|
upap_authwithpeer(unit, user, password)
|
|
int unit;
|
|
char *user, *password;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
|
|
/* Save the username and password we're given */
|
|
u->us_user = user;
|
|
u->us_userlen = strlen(user);
|
|
u->us_passwd = password;
|
|
u->us_passwdlen = strlen(password);
|
|
u->us_transmits = 0;
|
|
|
|
/* Lower layer up yet? */
|
|
if (u->us_clientstate == UPAPCS_INITIAL ||
|
|
u->us_clientstate == UPAPCS_PENDING) {
|
|
u->us_clientstate = UPAPCS_PENDING;
|
|
return;
|
|
}
|
|
|
|
upap_sauthreq(u); /* Start protocol */
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_authpeer - Authenticate our peer (start server).
|
|
*
|
|
* Set new state.
|
|
*/
|
|
void
|
|
upap_authpeer(unit)
|
|
int unit;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
|
|
/* Lower layer up yet? */
|
|
if (u->us_serverstate == UPAPSS_INITIAL ||
|
|
u->us_serverstate == UPAPSS_PENDING) {
|
|
u->us_serverstate = UPAPSS_PENDING;
|
|
return;
|
|
}
|
|
|
|
u->us_serverstate = UPAPSS_LISTEN;
|
|
if (u->us_reqtimeout > 0)
|
|
TIMEOUT(upap_reqtimeout, (caddr_t) u, u->us_reqtimeout);
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_timeout - Retransmission timer for sending auth-reqs expired.
|
|
*/
|
|
static void
|
|
upap_timeout(arg)
|
|
caddr_t arg;
|
|
{
|
|
upap_state *u = (upap_state *) arg;
|
|
|
|
if (u->us_clientstate != UPAPCS_AUTHREQ)
|
|
return;
|
|
|
|
if (u->us_transmits >= u->us_maxtransmits) {
|
|
/* give up in disgust */
|
|
syslog(LOG_ERR, "No response to PAP authenticate-requests");
|
|
u->us_clientstate = UPAPCS_BADAUTH;
|
|
auth_withpeer_fail(u->us_unit, PPP_PAP);
|
|
return;
|
|
}
|
|
|
|
upap_sauthreq(u); /* Send Authenticate-Request */
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_reqtimeout - Give up waiting for the peer to send an auth-req.
|
|
*/
|
|
static void
|
|
upap_reqtimeout(arg)
|
|
caddr_t arg;
|
|
{
|
|
upap_state *u = (upap_state *) arg;
|
|
|
|
if (u->us_serverstate != UPAPSS_LISTEN)
|
|
return; /* huh?? */
|
|
|
|
auth_peer_fail(u->us_unit, PPP_PAP);
|
|
u->us_serverstate = UPAPSS_BADAUTH;
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_lowerup - The lower layer is up.
|
|
*
|
|
* Start authenticating if pending.
|
|
*/
|
|
void
|
|
upap_lowerup(unit)
|
|
int unit;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
|
|
if (u->us_clientstate == UPAPCS_INITIAL)
|
|
u->us_clientstate = UPAPCS_CLOSED;
|
|
else if (u->us_clientstate == UPAPCS_PENDING) {
|
|
upap_sauthreq(u); /* send an auth-request */
|
|
}
|
|
|
|
if (u->us_serverstate == UPAPSS_INITIAL)
|
|
u->us_serverstate = UPAPSS_CLOSED;
|
|
else if (u->us_serverstate == UPAPSS_PENDING) {
|
|
u->us_serverstate = UPAPSS_LISTEN;
|
|
if (u->us_reqtimeout > 0)
|
|
TIMEOUT(upap_reqtimeout, (caddr_t) u, u->us_reqtimeout);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_lowerdown - The lower layer is down.
|
|
*
|
|
* Cancel all timeouts.
|
|
*/
|
|
void
|
|
upap_lowerdown(unit)
|
|
int unit;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
|
|
if (u->us_clientstate == UPAPCS_AUTHREQ) /* Timeout pending? */
|
|
UNTIMEOUT(upap_timeout, (caddr_t) u); /* Cancel timeout */
|
|
if (u->us_serverstate == UPAPSS_LISTEN && u->us_reqtimeout > 0)
|
|
UNTIMEOUT(upap_reqtimeout, (caddr_t) u);
|
|
|
|
u->us_clientstate = UPAPCS_INITIAL;
|
|
u->us_serverstate = UPAPSS_INITIAL;
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_protrej - Peer doesn't speak this protocol.
|
|
*
|
|
* This shouldn't happen. In any case, pretend lower layer went down.
|
|
*/
|
|
void
|
|
upap_protrej(unit)
|
|
int unit;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
|
|
if (u->us_clientstate == UPAPCS_AUTHREQ) {
|
|
syslog(LOG_ERR, "PAP authentication failed due to protocol-reject");
|
|
auth_withpeer_fail(unit, PPP_PAP);
|
|
}
|
|
if (u->us_serverstate == UPAPSS_LISTEN) {
|
|
syslog(LOG_ERR, "PAP authentication of peer failed (protocol-reject)");
|
|
auth_peer_fail(unit, PPP_PAP);
|
|
}
|
|
upap_lowerdown(unit);
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_input - Input UPAP packet.
|
|
*/
|
|
void
|
|
upap_input(unit, inpacket, l)
|
|
int unit;
|
|
u_char *inpacket;
|
|
int l;
|
|
{
|
|
upap_state *u = &upap[unit];
|
|
u_char *inp;
|
|
u_char code, id;
|
|
int len;
|
|
|
|
/*
|
|
* Parse header (code, id and length).
|
|
* If packet too short, drop it.
|
|
*/
|
|
inp = inpacket;
|
|
if (l < UPAP_HEADERLEN) {
|
|
UPAPDEBUG((LOG_INFO, "upap_input: rcvd short header."));
|
|
return;
|
|
}
|
|
GETCHAR(code, inp);
|
|
GETCHAR(id, inp);
|
|
GETSHORT(len, inp);
|
|
if (len < UPAP_HEADERLEN) {
|
|
UPAPDEBUG((LOG_INFO, "upap_input: rcvd illegal length."));
|
|
return;
|
|
}
|
|
if (len > l) {
|
|
UPAPDEBUG((LOG_INFO, "upap_input: rcvd short packet."));
|
|
return;
|
|
}
|
|
len -= UPAP_HEADERLEN;
|
|
|
|
/*
|
|
* Action depends on code.
|
|
*/
|
|
switch (code) {
|
|
case UPAP_AUTHREQ:
|
|
upap_rauthreq(u, inp, id, len);
|
|
break;
|
|
|
|
case UPAP_AUTHACK:
|
|
upap_rauthack(u, inp, id, len);
|
|
break;
|
|
|
|
case UPAP_AUTHNAK:
|
|
upap_rauthnak(u, inp, id, len);
|
|
break;
|
|
|
|
default: /* XXX Need code reject */
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_rauth - Receive Authenticate.
|
|
*/
|
|
static void
|
|
upap_rauthreq(u, inp, id, len)
|
|
upap_state *u;
|
|
u_char *inp;
|
|
int id;
|
|
int len;
|
|
{
|
|
u_char ruserlen, rpasswdlen;
|
|
char *ruser, *rpasswd;
|
|
int retcode;
|
|
char *msg;
|
|
int msglen;
|
|
|
|
UPAPDEBUG((LOG_INFO, "upap_rauth: Rcvd id %d.", id));
|
|
|
|
if (u->us_serverstate < UPAPSS_LISTEN)
|
|
return;
|
|
|
|
/*
|
|
* If we receive a duplicate authenticate-request, we are
|
|
* supposed to return the same status as for the first request.
|
|
*/
|
|
if (u->us_serverstate == UPAPSS_OPEN) {
|
|
upap_sresp(u, UPAP_AUTHACK, id, "", 0); /* return auth-ack */
|
|
return;
|
|
}
|
|
if (u->us_serverstate == UPAPSS_BADAUTH) {
|
|
upap_sresp(u, UPAP_AUTHNAK, id, "", 0); /* return auth-nak */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Parse user/passwd.
|
|
*/
|
|
if (len < sizeof (u_char)) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauth: rcvd short packet."));
|
|
return;
|
|
}
|
|
GETCHAR(ruserlen, inp);
|
|
len -= sizeof (u_char) + ruserlen + sizeof (u_char);
|
|
if (len < 0) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauth: rcvd short packet."));
|
|
return;
|
|
}
|
|
ruser = (char *) inp;
|
|
INCPTR(ruserlen, inp);
|
|
GETCHAR(rpasswdlen, inp);
|
|
if (len < rpasswdlen) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauth: rcvd short packet."));
|
|
return;
|
|
}
|
|
rpasswd = (char *) inp;
|
|
|
|
/*
|
|
* Check the username and password given.
|
|
*/
|
|
retcode = check_passwd(u->us_unit, ruser, ruserlen, rpasswd,
|
|
rpasswdlen, &msg, &msglen);
|
|
|
|
upap_sresp(u, retcode, id, msg, msglen);
|
|
|
|
if (retcode == UPAP_AUTHACK) {
|
|
u->us_serverstate = UPAPSS_OPEN;
|
|
auth_peer_success(u->us_unit, PPP_PAP);
|
|
} else {
|
|
u->us_serverstate = UPAPSS_BADAUTH;
|
|
auth_peer_fail(u->us_unit, PPP_PAP);
|
|
}
|
|
|
|
if (u->us_reqtimeout > 0)
|
|
UNTIMEOUT(upap_reqtimeout, (caddr_t) u);
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_rauthack - Receive Authenticate-Ack.
|
|
*/
|
|
static void
|
|
upap_rauthack(u, inp, id, len)
|
|
upap_state *u;
|
|
u_char *inp;
|
|
int id;
|
|
int len;
|
|
{
|
|
u_char msglen;
|
|
char *msg;
|
|
|
|
UPAPDEBUG((LOG_INFO, "upap_rauthack: Rcvd id %d.", id));
|
|
if (u->us_clientstate != UPAPCS_AUTHREQ) /* XXX */
|
|
return;
|
|
|
|
/*
|
|
* Parse message.
|
|
*/
|
|
if (len < sizeof (u_char)) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauthack: rcvd short packet."));
|
|
return;
|
|
}
|
|
GETCHAR(msglen, inp);
|
|
len -= sizeof (u_char);
|
|
if (len < msglen) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauthack: rcvd short packet."));
|
|
return;
|
|
}
|
|
msg = (char *) inp;
|
|
PRINTMSG(msg, msglen);
|
|
|
|
u->us_clientstate = UPAPCS_OPEN;
|
|
|
|
auth_withpeer_success(u->us_unit, PPP_PAP);
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_rauthnak - Receive Authenticate-Nakk.
|
|
*/
|
|
static void
|
|
upap_rauthnak(u, inp, id, len)
|
|
upap_state *u;
|
|
u_char *inp;
|
|
int id;
|
|
int len;
|
|
{
|
|
u_char msglen;
|
|
char *msg;
|
|
|
|
UPAPDEBUG((LOG_INFO, "upap_rauthnak: Rcvd id %d.", id));
|
|
if (u->us_clientstate != UPAPCS_AUTHREQ) /* XXX */
|
|
return;
|
|
|
|
/*
|
|
* Parse message.
|
|
*/
|
|
if (len < sizeof (u_char)) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauthnak: rcvd short packet."));
|
|
return;
|
|
}
|
|
GETCHAR(msglen, inp);
|
|
len -= sizeof (u_char);
|
|
if (len < msglen) {
|
|
UPAPDEBUG((LOG_INFO, "upap_rauthnak: rcvd short packet."));
|
|
return;
|
|
}
|
|
msg = (char *) inp;
|
|
PRINTMSG(msg, msglen);
|
|
|
|
u->us_clientstate = UPAPCS_BADAUTH;
|
|
|
|
syslog(LOG_ERR, "PAP authentication failed");
|
|
auth_withpeer_fail(u->us_unit, PPP_PAP);
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_sauthreq - Send an Authenticate-Request.
|
|
*/
|
|
static void
|
|
upap_sauthreq(u)
|
|
upap_state *u;
|
|
{
|
|
u_char *outp;
|
|
int outlen;
|
|
|
|
outlen = UPAP_HEADERLEN + 2 * sizeof (u_char) +
|
|
u->us_userlen + u->us_passwdlen;
|
|
outp = outpacket_buf;
|
|
|
|
MAKEHEADER(outp, PPP_PAP);
|
|
|
|
PUTCHAR(UPAP_AUTHREQ, outp);
|
|
PUTCHAR(++u->us_id, outp);
|
|
PUTSHORT(outlen, outp);
|
|
PUTCHAR(u->us_userlen, outp);
|
|
BCOPY(u->us_user, outp, u->us_userlen);
|
|
INCPTR(u->us_userlen, outp);
|
|
PUTCHAR(u->us_passwdlen, outp);
|
|
BCOPY(u->us_passwd, outp, u->us_passwdlen);
|
|
|
|
output(u->us_unit, outpacket_buf, outlen + PPP_HDRLEN);
|
|
|
|
UPAPDEBUG((LOG_INFO, "upap_sauth: Sent id %d.", u->us_id));
|
|
|
|
TIMEOUT(upap_timeout, (caddr_t) u, u->us_timeouttime);
|
|
++u->us_transmits;
|
|
u->us_clientstate = UPAPCS_AUTHREQ;
|
|
}
|
|
|
|
|
|
/*
|
|
* upap_sresp - Send a response (ack or nak).
|
|
*/
|
|
static void
|
|
upap_sresp(u, code, id, msg, msglen)
|
|
upap_state *u;
|
|
u_char code, id;
|
|
char *msg;
|
|
int msglen;
|
|
{
|
|
u_char *outp;
|
|
int outlen;
|
|
|
|
outlen = UPAP_HEADERLEN + sizeof (u_char) + msglen;
|
|
outp = outpacket_buf;
|
|
MAKEHEADER(outp, PPP_PAP);
|
|
|
|
PUTCHAR(code, outp);
|
|
PUTCHAR(id, outp);
|
|
PUTSHORT(outlen, outp);
|
|
PUTCHAR(msglen, outp);
|
|
BCOPY(msg, outp, msglen);
|
|
output(u->us_unit, outpacket_buf, outlen + PPP_HDRLEN);
|
|
|
|
UPAPDEBUG((LOG_INFO, "upap_sresp: Sent code %d, id %d.", code, id));
|
|
}
|
|
|
|
/*
|
|
* upap_printpkt - print the contents of a PAP packet.
|
|
*/
|
|
char *upap_codenames[] = {
|
|
"AuthReq", "AuthAck", "AuthNak"
|
|
};
|
|
|
|
int
|
|
upap_printpkt(p, plen, printer, arg)
|
|
u_char *p;
|
|
int plen;
|
|
void (*printer) __P((void *, char *, ...));
|
|
void *arg;
|
|
{
|
|
int code, id, len;
|
|
int mlen, ulen, wlen;
|
|
char *user, *pwd, *msg;
|
|
u_char *pstart;
|
|
|
|
if (plen < UPAP_HEADERLEN)
|
|
return 0;
|
|
pstart = p;
|
|
GETCHAR(code, p);
|
|
GETCHAR(id, p);
|
|
GETSHORT(len, p);
|
|
if (len < UPAP_HEADERLEN || len > plen)
|
|
return 0;
|
|
|
|
if (code >= 1 && code <= sizeof(upap_codenames) / sizeof(char *))
|
|
printer(arg, " %s", upap_codenames[code-1]);
|
|
else
|
|
printer(arg, " code=0x%x", code);
|
|
printer(arg, " id=0x%x", id);
|
|
len -= UPAP_HEADERLEN;
|
|
switch (code) {
|
|
case UPAP_AUTHREQ:
|
|
if (len < 1)
|
|
break;
|
|
ulen = p[0];
|
|
if (len < ulen + 2)
|
|
break;
|
|
wlen = p[ulen + 1];
|
|
if (len < ulen + wlen + 2)
|
|
break;
|
|
user = (char *) (p + 1);
|
|
pwd = (char *) (p + ulen + 2);
|
|
p += ulen + wlen + 2;
|
|
len -= ulen + wlen + 2;
|
|
printer(arg, " user=");
|
|
print_string(user, ulen, printer, arg);
|
|
printer(arg, " password=");
|
|
print_string(pwd, wlen, printer, arg);
|
|
break;
|
|
case UPAP_AUTHACK:
|
|
case UPAP_AUTHNAK:
|
|
if (len < 1)
|
|
break;
|
|
mlen = p[0];
|
|
if (len < mlen + 1)
|
|
break;
|
|
msg = (char *) (p + 1);
|
|
p += mlen + 1;
|
|
len -= mlen + 1;
|
|
printer(arg, "msg=");
|
|
print_string(msg, mlen, printer, arg);
|
|
break;
|
|
}
|
|
|
|
/* print the rest of the bytes in the packet */
|
|
for (; len > 0; --len) {
|
|
GETCHAR(code, p);
|
|
printer(arg, " %.2x", code);
|
|
}
|
|
|
|
return p - pstart;
|
|
}
|