minix/lib/liblwip/netif/ppp/pap.c

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/*****************************************************************************
* pap.c - Network Password Authentication Protocol program file.
*
* Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
* portions Copyright (c) 1997 by Global Election Systems Inc.
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice and the following disclaimer are included verbatim in any
* distributions. No written agreement, license, or royalty fee is required
* for any of the authorized uses.
*
* THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
******************************************************************************
* REVISION HISTORY
*
* 03-01-01 Marc Boucher <marc@mbsi.ca>
* Ported to lwIP.
* 97-12-12 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
* Original.
*****************************************************************************/
/*
* 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.
*/
#include "lwip/opt.h"
#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
#if PAP_SUPPORT /* don't build if not configured for use in lwipopts.h */
#include "ppp.h"
#include "pppdebug.h"
#include "auth.h"
#include "pap.h"
#include <string.h>
#if 0 /* UNUSED */
static bool hide_password = 1;
/*
* Command-line options.
*/
static option_t pap_option_list[] = {
{ "hide-password", o_bool, &hide_password,
"Don't output passwords to log", 1 },
{ "show-password", o_bool, &hide_password,
"Show password string in debug log messages", 0 },
{ "pap-restart", o_int, &upap[0].us_timeouttime,
"Set retransmit timeout for PAP" },
{ "pap-max-authreq", o_int, &upap[0].us_maxtransmits,
"Set max number of transmissions for auth-reqs" },
{ "pap-timeout", o_int, &upap[0].us_reqtimeout,
"Set time limit for peer PAP authentication" },
{ NULL }
};
#endif
/*
* Protocol entry points.
*/
static void upap_init (int);
static void upap_lowerup (int);
static void upap_lowerdown (int);
static void upap_input (int, u_char *, int);
static void upap_protrej (int);
#if PPP_ADDITIONAL_CALLBACKS
static int upap_printpkt (u_char *, int, void (*)(void *, char *, ...), void *);
#endif /* PPP_ADDITIONAL_CALLBACKS */
struct protent pap_protent = {
PPP_PAP,
upap_init,
upap_input,
upap_protrej,
upap_lowerup,
upap_lowerdown,
NULL,
NULL,
#if PPP_ADDITIONAL_CALLBACKS
upap_printpkt,
NULL,
#endif /* PPP_ADDITIONAL_CALLBACKS */
1,
"PAP",
#if PPP_ADDITIONAL_CALLBACKS
NULL,
NULL,
NULL
#endif /* PPP_ADDITIONAL_CALLBACKS */
};
upap_state upap[NUM_PPP]; /* UPAP state; one for each unit */
static void upap_timeout (void *);
static void upap_reqtimeout(void *);
static void upap_rauthreq (upap_state *, u_char *, u_char, int);
static void upap_rauthack (upap_state *, u_char *, int, int);
static void upap_rauthnak (upap_state *, u_char *, int, int);
static void upap_sauthreq (upap_state *);
static void upap_sresp (upap_state *, u_char, u_char, char *, int);
/*
* upap_init - Initialize a UPAP unit.
*/
static void
upap_init(int unit)
{
upap_state *u = &upap[unit];
UPAPDEBUG(LOG_INFO, ("upap_init: %d\n", 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(int unit, char *user, char *password)
{
upap_state *u = &upap[unit];
UPAPDEBUG(LOG_INFO, ("upap_authwithpeer: %d user=%s password=%s s=%d\n",
unit, user, password, u->us_clientstate));
/* Save the username and password we're given */
u->us_user = user;
u->us_userlen = (int)strlen(user);
u->us_passwd = password;
u->us_passwdlen = (int)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(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, u, u->us_reqtimeout);
}
}
/*
* upap_timeout - Retransmission timer for sending auth-reqs expired.
*/
static void
upap_timeout(void *arg)
{
upap_state *u = (upap_state *) arg;
UPAPDEBUG(LOG_INFO, ("upap_timeout: %d timeout %d expired s=%d\n",
u->us_unit, u->us_timeouttime, u->us_clientstate));
if (u->us_clientstate != UPAPCS_AUTHREQ) {
UPAPDEBUG(LOG_INFO, ("upap_timeout: not in AUTHREQ state!\n"));
return;
}
if (u->us_transmits >= u->us_maxtransmits) {
/* give up in disgust */
UPAPDEBUG(LOG_ERR, ("No response to PAP authenticate-requests\n"));
u->us_clientstate = UPAPCS_BADAUTH;
auth_withpeer_fail(u->us_unit, PPP_PAP);
return;
}
upap_sauthreq(u); /* Send Authenticate-Request and set upap timeout*/
}
/*
* upap_reqtimeout - Give up waiting for the peer to send an auth-req.
*/
static void
upap_reqtimeout(void *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.
*/
static void
upap_lowerup(int unit)
{
upap_state *u = &upap[unit];
UPAPDEBUG(LOG_INFO, ("upap_lowerup: init %d clientstate s=%d\n", unit, u->us_clientstate));
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 */
/* now client state is UPAPCS__AUTHREQ */
}
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, u, u->us_reqtimeout);
}
}
}
/*
* upap_lowerdown - The lower layer is down.
*
* Cancel all timeouts.
*/
static void
upap_lowerdown(int unit)
{
upap_state *u = &upap[unit];
UPAPDEBUG(LOG_INFO, ("upap_lowerdown: %d s=%d\n", unit, u->us_clientstate));
if (u->us_clientstate == UPAPCS_AUTHREQ) { /* Timeout pending? */
UNTIMEOUT(upap_timeout, u); /* Cancel timeout */
}
if (u->us_serverstate == UPAPSS_LISTEN && u->us_reqtimeout > 0) {
UNTIMEOUT(upap_reqtimeout, 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.
*/
static void
upap_protrej(int unit)
{
upap_state *u = &upap[unit];
if (u->us_clientstate == UPAPCS_AUTHREQ) {
UPAPDEBUG(LOG_ERR, ("PAP authentication failed due to protocol-reject\n"));
auth_withpeer_fail(unit, PPP_PAP);
}
if (u->us_serverstate == UPAPSS_LISTEN) {
UPAPDEBUG(LOG_ERR, ("PAP authentication of peer failed (protocol-reject)\n"));
auth_peer_fail(unit, PPP_PAP);
}
upap_lowerdown(unit);
}
/*
* upap_input - Input UPAP packet.
*/
static void
upap_input(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 < (int)UPAP_HEADERLEN) {
UPAPDEBUG(LOG_INFO, ("pap_input: rcvd short header.\n"));
return;
}
GETCHAR(code, inp);
GETCHAR(id, inp);
GETSHORT(len, inp);
if (len < (int)UPAP_HEADERLEN) {
UPAPDEBUG(LOG_INFO, ("pap_input: rcvd illegal length.\n"));
return;
}
if (len > l) {
UPAPDEBUG(LOG_INFO, ("pap_input: rcvd short packet.\n"));
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 */
UPAPDEBUG(LOG_INFO, ("pap_input: UNHANDLED default: code: %d, id: %d, len: %d.\n", code, id, len));
break;
}
}
/*
* upap_rauth - Receive Authenticate.
*/
static void
upap_rauthreq(upap_state *u, u_char *inp, u_char id, int len)
{
u_char ruserlen, rpasswdlen;
char *ruser, *rpasswd;
u_char retcode;
char *msg;
int msglen;
UPAPDEBUG(LOG_INFO, ("pap_rauth: Rcvd id %d.\n", 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 < (int)sizeof (u_char)) {
UPAPDEBUG(LOG_INFO, ("pap_rauth: rcvd short packet.\n"));
return;
}
GETCHAR(ruserlen, inp);
len -= sizeof (u_char) + ruserlen + sizeof (u_char);
if (len < 0) {
UPAPDEBUG(LOG_INFO, ("pap_rauth: rcvd short packet.\n"));
return;
}
ruser = (char *) inp;
INCPTR(ruserlen, inp);
GETCHAR(rpasswdlen, inp);
if (len < rpasswdlen) {
UPAPDEBUG(LOG_INFO, ("pap_rauth: rcvd short packet.\n"));
return;
}
rpasswd = (char *) inp;
/*
* Check the username and password given.
*/
retcode = check_passwd(u->us_unit, ruser, ruserlen, rpasswd, rpasswdlen, &msg, &msglen);
/* lwip: currently retcode is always UPAP_AUTHACK */
BZERO(rpasswd, rpasswdlen);
upap_sresp(u, retcode, id, msg, msglen);
if (retcode == UPAP_AUTHACK) {
u->us_serverstate = UPAPSS_OPEN;
auth_peer_success(u->us_unit, PPP_PAP, ruser, ruserlen);
} else {
u->us_serverstate = UPAPSS_BADAUTH;
auth_peer_fail(u->us_unit, PPP_PAP);
}
if (u->us_reqtimeout > 0) {
UNTIMEOUT(upap_reqtimeout, u);
}
}
/*
* upap_rauthack - Receive Authenticate-Ack.
*/
static void
upap_rauthack(upap_state *u, u_char *inp, int id, int len)
{
u_char msglen;
char *msg;
LWIP_UNUSED_ARG(id);
UPAPDEBUG(LOG_INFO, ("pap_rauthack: Rcvd id %d s=%d\n", id, u->us_clientstate));
if (u->us_clientstate != UPAPCS_AUTHREQ) { /* XXX */
UPAPDEBUG(LOG_INFO, ("pap_rauthack: us_clientstate != UPAPCS_AUTHREQ\n"));
return;
}
/*
* Parse message.
*/
if (len < (int)sizeof (u_char)) {
UPAPDEBUG(LOG_INFO, ("pap_rauthack: ignoring missing msg-length.\n"));
} else {
GETCHAR(msglen, inp);
if (msglen > 0) {
len -= sizeof (u_char);
if (len < msglen) {
UPAPDEBUG(LOG_INFO, ("pap_rauthack: rcvd short packet.\n"));
return;
}
msg = (char *) inp;
PRINTMSG(msg, msglen);
}
}
UNTIMEOUT(upap_timeout, u); /* Cancel timeout */
u->us_clientstate = UPAPCS_OPEN;
auth_withpeer_success(u->us_unit, PPP_PAP);
}
/*
* upap_rauthnak - Receive Authenticate-Nak.
*/
static void
upap_rauthnak(upap_state *u, u_char *inp, int id, int len)
{
u_char msglen;
char *msg;
LWIP_UNUSED_ARG(id);
UPAPDEBUG(LOG_INFO, ("pap_rauthnak: Rcvd id %d s=%d\n", id, u->us_clientstate));
if (u->us_clientstate != UPAPCS_AUTHREQ) { /* XXX */
return;
}
/*
* Parse message.
*/
if (len < sizeof (u_char)) {
UPAPDEBUG(LOG_INFO, ("pap_rauthnak: ignoring missing msg-length.\n"));
} else {
GETCHAR(msglen, inp);
if(msglen > 0) {
len -= sizeof (u_char);
if (len < msglen) {
UPAPDEBUG(LOG_INFO, ("pap_rauthnak: rcvd short packet.\n"));
return;
}
msg = (char *) inp;
PRINTMSG(msg, msglen);
}
}
u->us_clientstate = UPAPCS_BADAUTH;
UPAPDEBUG(LOG_ERR, ("PAP authentication failed\n"));
auth_withpeer_fail(u->us_unit, PPP_PAP);
}
/*
* upap_sauthreq - Send an Authenticate-Request.
*/
static void
upap_sauthreq(upap_state *u)
{
u_char *outp;
int outlen;
outlen = UPAP_HEADERLEN + 2 * sizeof (u_char)
+ u->us_userlen + u->us_passwdlen;
outp = outpacket_buf[u->us_unit];
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);
pppWrite(u->us_unit, outpacket_buf[u->us_unit], outlen + PPP_HDRLEN);
UPAPDEBUG(LOG_INFO, ("pap_sauth: Sent id %d\n", u->us_id));
TIMEOUT(upap_timeout, u, u->us_timeouttime);
++u->us_transmits;
u->us_clientstate = UPAPCS_AUTHREQ;
}
/*
* upap_sresp - Send a response (ack or nak).
*/
static void
upap_sresp(upap_state *u, u_char code, u_char id, char *msg, int msglen)
{
u_char *outp;
int outlen;
outlen = UPAP_HEADERLEN + sizeof (u_char) + msglen;
outp = outpacket_buf[u->us_unit];
MAKEHEADER(outp, PPP_PAP);
PUTCHAR(code, outp);
PUTCHAR(id, outp);
PUTSHORT(outlen, outp);
PUTCHAR(msglen, outp);
BCOPY(msg, outp, msglen);
pppWrite(u->us_unit, outpacket_buf[u->us_unit], outlen + PPP_HDRLEN);
UPAPDEBUG(LOG_INFO, ("pap_sresp: Sent code %d, id %d s=%d\n", code, id, u->us_clientstate));
}
#if PPP_ADDITIONAL_CALLBACKS
static char *upap_codenames[] = {
"AuthReq", "AuthAck", "AuthNak"
};
/*
* upap_printpkt - print the contents of a PAP packet.
*/
static int upap_printpkt(
u_char *p,
int plen,
void (*printer) (void *, char *, ...),
void *arg
)
{
LWIP_UNUSED_ARG(p);
LWIP_UNUSED_ARG(plen);
LWIP_UNUSED_ARG(printer);
LWIP_UNUSED_ARG(arg);
return 0;
}
#endif /* PPP_ADDITIONAL_CALLBACKS */
#endif /* PAP_SUPPORT */
#endif /* PPP_SUPPORT */