freebsd-dev/usr.sbin/ppp/pap.c
Brian Somers 250be50b72 Compensate for dodgy Win98/WinME MSCHAPv2 responses later in the code
path... after we've talked to any RADIUS servers involved, so that we
haven't touched the data before it gets to the server.

Make it clearer in the code that this compensation is done by setting
a flag to a value of zero, a flag which rfc2759 says *MUST* be zero.

While we're here, don't bother passing the peer challenge into
radius_Authenticate().  It's already part of the key we're passing in
(this becomes obvious now that I've structured that data...).

This ``fix'' doesn't help to authenticate Win98/WinME users in my test
environment as ports/net/freeradius seems to ignore the flag
completely anyway, but it may help with other RADIUS servers.
2002-06-17 01:12:38 +00:00

304 lines
8.8 KiB
C

/*-
* Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
* based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
* Internet Initiative Japan, Inc (IIJ)
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND 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 AUTHOR OR 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <stdlib.h>
#include <string.h> /* strlen/memcpy */
#include <termios.h>
#include "layer.h"
#include "mbuf.h"
#include "log.h"
#include "defs.h"
#include "timer.h"
#include "fsm.h"
#include "auth.h"
#include "pap.h"
#include "lqr.h"
#include "hdlc.h"
#include "lcp.h"
#include "proto.h"
#include "async.h"
#include "throughput.h"
#include "ccp.h"
#include "link.h"
#include "descriptor.h"
#include "physical.h"
#include "iplist.h"
#include "slcompress.h"
#include "ncpaddr.h"
#include "ipcp.h"
#include "filter.h"
#include "mp.h"
#ifndef NORADIUS
#include "radius.h"
#endif
#include "ipv6cp.h"
#include "ncp.h"
#include "bundle.h"
#include "chat.h"
#include "chap.h"
#include "cbcp.h"
#include "datalink.h"
static const char * const papcodes[] = {
"???", "REQUEST", "SUCCESS", "FAILURE"
};
#define MAXPAPCODE (sizeof papcodes / sizeof papcodes[0] - 1)
static void
pap_Req(struct authinfo *authp)
{
struct bundle *bundle = authp->physical->dl->bundle;
struct fsmheader lh;
struct mbuf *bp;
u_char *cp;
int namelen, keylen, plen;
namelen = strlen(bundle->cfg.auth.name);
keylen = strlen(bundle->cfg.auth.key);
plen = namelen + keylen + 2;
log_Printf(LogDEBUG, "pap_Req: namelen = %d, keylen = %d\n", namelen, keylen);
log_Printf(LogPHASE, "Pap Output: %s ********\n", bundle->cfg.auth.name);
if (*bundle->cfg.auth.name == '\0')
log_Printf(LogWARN, "Sending empty PAP authname!\n");
lh.code = PAP_REQUEST;
lh.id = authp->id;
lh.length = htons(plen + sizeof(struct fsmheader));
bp = m_get(plen + sizeof(struct fsmheader), MB_PAPOUT);
memcpy(MBUF_CTOP(bp), &lh, sizeof(struct fsmheader));
cp = MBUF_CTOP(bp) + sizeof(struct fsmheader);
*cp++ = namelen;
memcpy(cp, bundle->cfg.auth.name, namelen);
cp += namelen;
*cp++ = keylen;
memcpy(cp, bundle->cfg.auth.key, keylen);
link_PushPacket(&authp->physical->link, bp, bundle,
LINK_QUEUES(&authp->physical->link) - 1, PROTO_PAP);
}
static void
SendPapCode(struct authinfo *authp, int code, const char *message)
{
struct fsmheader lh;
struct mbuf *bp;
u_char *cp;
int plen, mlen;
lh.code = code;
lh.id = authp->id;
mlen = strlen(message);
plen = mlen + 1;
lh.length = htons(plen + sizeof(struct fsmheader));
bp = m_get(plen + sizeof(struct fsmheader), MB_PAPOUT);
memcpy(MBUF_CTOP(bp), &lh, sizeof(struct fsmheader));
cp = MBUF_CTOP(bp) + sizeof(struct fsmheader);
/*
* If our message is longer than 255 bytes, truncate the length to
* 255 and send the entire message anyway. Maybe the other end will
* display it... (see pap_Input() !)
*/
*cp++ = mlen > 255 ? 255 : mlen;
memcpy(cp, message, mlen);
log_Printf(LogPHASE, "Pap Output: %s\n", papcodes[code]);
link_PushPacket(&authp->physical->link, bp, authp->physical->dl->bundle,
LINK_QUEUES(&authp->physical->link) - 1, PROTO_PAP);
}
static void
pap_Success(struct authinfo *authp)
{
struct bundle *bundle = authp->physical->dl->bundle;
datalink_GotAuthname(authp->physical->dl, authp->in.name);
#ifndef NORADIUS
if (*bundle->radius.cfg.file && bundle->radius.repstr)
SendPapCode(authp, PAP_ACK, bundle->radius.repstr);
else
#endif
SendPapCode(authp, PAP_ACK, "Greetings!!");
authp->physical->link.lcp.auth_ineed = 0;
if (Enabled(bundle, OPT_UTMP))
physical_Login(authp->physical, authp->in.name);
if (authp->physical->link.lcp.auth_iwait == 0)
/*
* Either I didn't need to authenticate, or I've already been
* told that I got the answer right.
*/
datalink_AuthOk(authp->physical->dl);
}
static void
pap_Failure(struct authinfo *authp)
{
SendPapCode(authp, PAP_NAK, "Login incorrect");
datalink_AuthNotOk(authp->physical->dl);
}
void
pap_Init(struct authinfo *pap, struct physical *p)
{
auth_Init(pap, p, pap_Req, pap_Success, pap_Failure);
}
struct mbuf *
pap_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
{
struct physical *p = link2physical(l);
struct authinfo *authp = &p->dl->pap;
u_char nlen, klen, *key;
const char *txt;
int txtlen;
if (p == NULL) {
log_Printf(LogERROR, "pap_Input: Not a physical link - dropped\n");
m_freem(bp);
return NULL;
}
if (bundle_Phase(bundle) != PHASE_NETWORK &&
bundle_Phase(bundle) != PHASE_AUTHENTICATE) {
log_Printf(LogPHASE, "Unexpected pap input - dropped !\n");
m_freem(bp);
return NULL;
}
if ((bp = auth_ReadHeader(authp, bp)) == NULL &&
ntohs(authp->in.hdr.length) == 0) {
log_Printf(LogWARN, "Pap Input: Truncated header !\n");
return NULL;
}
if (authp->in.hdr.code == 0 || authp->in.hdr.code > MAXPAPCODE) {
log_Printf(LogPHASE, "Pap Input: %d: Bad PAP code !\n", authp->in.hdr.code);
m_freem(bp);
return NULL;
}
if (authp->in.hdr.code != PAP_REQUEST && authp->id != authp->in.hdr.id &&
Enabled(bundle, OPT_IDCHECK)) {
/* Wrong conversation dude ! */
log_Printf(LogPHASE, "Pap Input: %s dropped (got id %d, not %d)\n",
papcodes[authp->in.hdr.code], authp->in.hdr.id, authp->id);
m_freem(bp);
return NULL;
}
m_settype(bp, MB_PAPIN);
authp->id = authp->in.hdr.id; /* We respond with this id */
if (bp) {
bp = mbuf_Read(bp, &nlen, 1);
if (authp->in.hdr.code == PAP_ACK) {
/*
* Don't restrict the length of our acknowledgement freetext to
* nlen (a one-byte length). Show the rest of the ack packet
* instead. This isn't really part of the protocol.....
*/
bp = m_pullup(bp);
txt = MBUF_CTOP(bp);
txtlen = m_length(bp);
} else {
bp = auth_ReadName(authp, bp, nlen);
txt = authp->in.name;
txtlen = strlen(authp->in.name);
}
} else {
txt = "";
txtlen = 0;
}
log_Printf(LogPHASE, "Pap Input: %s (%.*s)\n",
papcodes[authp->in.hdr.code], txtlen, txt);
switch (authp->in.hdr.code) {
case PAP_REQUEST:
if (bp == NULL) {
log_Printf(LogPHASE, "Pap Input: No key given !\n");
break;
}
bp = mbuf_Read(bp, &klen, 1);
if (m_length(bp) < klen) {
log_Printf(LogERROR, "Pap Input: Truncated key !\n");
break;
}
if ((key = malloc(klen+1)) == NULL) {
log_Printf(LogERROR, "Pap Input: Out of memory !\n");
break;
}
bp = mbuf_Read(bp, key, klen);
key[klen] = '\0';
#ifndef NORADIUS
if (*bundle->radius.cfg.file) {
if (!radius_Authenticate(&bundle->radius, authp, authp->in.name,
key, strlen(key), NULL, 0))
pap_Failure(authp);
} else
#endif
if (auth_Validate(bundle, authp->in.name, key, p))
pap_Success(authp);
else
pap_Failure(authp);
free(key);
break;
case PAP_ACK:
auth_StopTimer(authp);
if (p->link.lcp.auth_iwait == PROTO_PAP) {
p->link.lcp.auth_iwait = 0;
if (p->link.lcp.auth_ineed == 0)
/*
* We've succeeded in our ``login''
* If we're not expecting the peer to authenticate (or he already
* has), proceed to network phase.
*/
datalink_AuthOk(p->dl);
}
break;
case PAP_NAK:
auth_StopTimer(authp);
datalink_AuthNotOk(p->dl);
break;
}
m_freem(bp);
return NULL;
}