usr.sbin/ppp/pap.c

   1 /*-
   2  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
   3  *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
   4  *                           Internet Initiative Japan, Inc (IIJ)
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD: src/usr.sbin/ppp/pap.c,v 1.42.2.4 2002/09/01 02:12:29 brian Exp $
  29  */
  30
  31 #include <sys/param.h>
  32 #include <netinet/in.h>
  33 #include <netinet/in_systm.h>
  34 #include <netinet/ip.h>
  35 #include <sys/socket.h>
  36 #include <sys/un.h>
  37
  38 #include <stdlib.h>
  39 #include <string.h>             /* strlen/memcpy */
  40 #include <termios.h>
  41
  42 #include "layer.h"
  43 #include "mbuf.h"
  44 #include "log.h"
  45 #include "defs.h"
  46 #include "timer.h"
  47 #include "fsm.h"
  48 #include "auth.h"
  49 #include "pap.h"
  50 #include "lqr.h"
  51 #include "hdlc.h"
  52 #include "lcp.h"
  53 #include "proto.h"
  54 #include "async.h"
  55 #include "throughput.h"
  56 #include "ccp.h"
  57 #include "link.h"
  58 #include "descriptor.h"
  59 #include "physical.h"
  60 #include "iplist.h"
  61 #include "slcompress.h"
  62 #include "ncpaddr.h"
  63 #include "ipcp.h"
  64 #include "filter.h"
  65 #include "mp.h"
  66 #ifndef NORADIUS
  67 #include "radius.h"
  68 #endif
  69 #include "ipv6cp.h"
  70 #include "ncp.h"
  71 #include "bundle.h"
  72 #include "chat.h"
  73 #include "chap.h"
  74 #include "cbcp.h"
  75 #include "datalink.h"
  76
  77 static const char * const papcodes[] = {
  78   "???", "REQUEST", "SUCCESS", "FAILURE"
  79 };
  80 #define MAXPAPCODE (NELEM(papcodes) - 1)
  81
  82 static void
  83 pap_Req(struct authinfo *authp)
  84 {
  85   struct bundle *bundle = authp->physical->dl->bundle;
  86   struct fsmheader lh;
  87   struct mbuf *bp;
  88   u_char *cp;
  89   int namelen, keylen, plen;
  90
  91   namelen = strlen(bundle->cfg.auth.name);
  92   keylen = strlen(bundle->cfg.auth.key);
  93   plen = namelen + keylen + 2;
  94   log_Printf(LogDEBUG, "pap_Req: namelen = %d, keylen = %d\n", namelen, keylen);
  95   log_Printf(LogPHASE, "Pap Output: %s ********\n", bundle->cfg.auth.name);
  96   if (*bundle->cfg.auth.name == '\0')
  97     log_Printf(LogWARN, "Sending empty PAP authname!\n");
  98   lh.code = PAP_REQUEST;
  99   lh.id = authp->id;
 100   lh.length = htons(plen + sizeof(struct fsmheader));
 101   bp = m_get(plen + sizeof(struct fsmheader), MB_PAPOUT);
 102   memcpy(MBUF_CTOP(bp), &lh, sizeof(struct fsmheader));
 103   cp = MBUF_CTOP(bp) + sizeof(struct fsmheader);
 104   *cp++ = namelen;
 105   memcpy(cp, bundle->cfg.auth.name, namelen);
 106   cp += namelen;
 107   *cp++ = keylen;
 108   memcpy(cp, bundle->cfg.auth.key, keylen);
 109   link_PushPacket(&authp->physical->link, bp, bundle,
 110                   LINK_QUEUES(&authp->physical->link) - 1, PROTO_PAP);
 111 }
 112
 113 static void
 114 SendPapCode(struct authinfo *authp, int code, const char *message)
 115 {
 116   struct fsmheader lh;
 117   struct mbuf *bp;
 118   u_char *cp;
 119   int plen, mlen;
 120
 121   lh.code = code;
 122   lh.id = authp->id;
 123   mlen = strlen(message);
 124   plen = mlen + 1;
 125   lh.length = htons(plen + sizeof(struct fsmheader));
 126   bp = m_get(plen + sizeof(struct fsmheader), MB_PAPOUT);
 127   memcpy(MBUF_CTOP(bp), &lh, sizeof(struct fsmheader));
 128   cp = MBUF_CTOP(bp) + sizeof(struct fsmheader);
 129   /*
 130    * If our message is longer than 255 bytes, truncate the length to
 131    * 255 and send the entire message anyway.  Maybe the other end will
 132    * display it... (see pap_Input() !)
 133    */
 134   *cp++ = mlen > 255 ? 255 : mlen;
 135   memcpy(cp, message, mlen);
 136   log_Printf(LogPHASE, "Pap Output: %s\n", papcodes[code]);
 137
 138   link_PushPacket(&authp->physical->link, bp, authp->physical->dl->bundle,
 139                   LINK_QUEUES(&authp->physical->link) - 1, PROTO_PAP);
 140 }
 141
 142 static void
 143 pap_Success(struct authinfo *authp)
 144 {
 145   struct bundle *bundle = authp->physical->dl->bundle;
 146
 147   datalink_GotAuthname(authp->physical->dl, authp->in.name);
 148 #ifndef NORADIUS
 149   if (*bundle->radius.cfg.file && bundle->radius.repstr)
 150     SendPapCode(authp, PAP_ACK, bundle->radius.repstr);
 151   else
 152 #endif
 153     SendPapCode(authp, PAP_ACK, "Greetings!!");
 154   authp->physical->link.lcp.auth_ineed = 0;
 155   if (Enabled(bundle, OPT_UTMP))
 156     physical_Login(authp->physical, authp->in.name);
 157
 158   if (authp->physical->link.lcp.auth_iwait == 0)
 159     /*
 160      * Either I didn't need to authenticate, or I've already been
 161      * told that I got the answer right.
 162      */
 163     datalink_AuthOk(authp->physical->dl);
 164 }
 165
 166 static void
 167 pap_Failure(struct authinfo *authp)
 168 {
 169   SendPapCode(authp, PAP_NAK, "Login incorrect");
 170   datalink_AuthNotOk(authp->physical->dl);
 171 }
 172
 173 void
 174 pap_Init(struct authinfo *pap, struct physical *p)
 175 {
 176   auth_Init(pap, p, pap_Req, pap_Success, pap_Failure);
 177 }
 178
 179 struct mbuf *
 180 pap_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
 181 {
 182   struct physical *p = link2physical(l);
 183   struct authinfo *authp = &p->dl->pap;
 184   u_char nlen, klen, *key;
 185   const char *txt;
 186   int txtlen;
 187
 188   if (p == NULL) {
 189     log_Printf(LogERROR, "pap_Input: Not a physical link - dropped\n");
 190     m_freem(bp);
 191     return NULL;
 192   }
 193
 194   if (bundle_Phase(bundle) != PHASE_NETWORK &&
 195       bundle_Phase(bundle) != PHASE_AUTHENTICATE) {
 196     log_Printf(LogPHASE, "Unexpected pap input - dropped !\n");
 197     m_freem(bp);
 198     return NULL;
 199   }
 200
 201   if ((bp = auth_ReadHeader(authp, bp)) == NULL &&
 202       ntohs(authp->in.hdr.length) == 0) {
 203     log_Printf(LogWARN, "Pap Input: Truncated header !\n");
 204     return NULL;
 205   }
 206
 207   if (authp->in.hdr.code == 0 || authp->in.hdr.code > MAXPAPCODE) {
 208     log_Printf(LogPHASE, "Pap Input: %d: Bad PAP code !\n", authp->in.hdr.code);
 209     m_freem(bp);
 210     return NULL;
 211   }
 212
 213   if (authp->in.hdr.code != PAP_REQUEST && authp->id != authp->in.hdr.id &&
 214       Enabled(bundle, OPT_IDCHECK)) {
 215     /* Wrong conversation dude ! */
 216     log_Printf(LogPHASE, "Pap Input: %s dropped (got id %d, not %d)\n",
 217                papcodes[authp->in.hdr.code], authp->in.hdr.id, authp->id);
 218     m_freem(bp);
 219     return NULL;
 220   }
 221   m_settype(bp, MB_PAPIN);
 222   authp->id = authp->in.hdr.id;         /* We respond with this id */
 223
 224   if (bp) {
 225     bp = mbuf_Read(bp, &nlen, 1);
 226     if (authp->in.hdr.code == PAP_ACK) {
 227       /*
 228        * Don't restrict the length of our acknowledgement freetext to
 229        * nlen (a one-byte length).  Show the rest of the ack packet
 230        * instead.  This isn't really part of the protocol.....
 231        */
 232       bp = m_pullup(bp);
 233       txt = MBUF_CTOP(bp);
 234       txtlen = m_length(bp);
 235     } else {
 236       bp = auth_ReadName(authp, bp, nlen);
 237       txt = authp->in.name;
 238       txtlen = strlen(authp->in.name);
 239     }
 240   } else {
 241     txt = "";
 242     txtlen = 0;
 243   }
 244
 245   log_Printf(LogPHASE, "Pap Input: %s (%.*s)\n",
 246              papcodes[authp->in.hdr.code], txtlen, txt);
 247
 248   switch (authp->in.hdr.code) {
 249     case PAP_REQUEST:
 250       if (bp == NULL) {
 251         log_Printf(LogPHASE, "Pap Input: No key given !\n");
 252         break;
 253       }
 254       bp = mbuf_Read(bp, &klen, 1);
 255       if (m_length(bp) < klen) {
 256         log_Printf(LogERROR, "Pap Input: Truncated key !\n");
 257         break;
 258       }
 259       if ((key = malloc(klen+1)) == NULL) {
 260         log_Printf(LogERROR, "Pap Input: Out of memory !\n");
 261         break;
 262       }
 263       bp = mbuf_Read(bp, key, klen);
 264       key[klen] = '\0';
 265
 266 #ifndef NORADIUS
 267       if (*bundle->radius.cfg.file) {
 268         if (!radius_Authenticate(&bundle->radius, authp, authp->in.name,
 269                                  key, strlen(key), NULL, 0))
 270           pap_Failure(authp);
 271       } else
 272 #endif
 273       if (auth_Validate(bundle, authp->in.name, key))
 274         pap_Success(authp);
 275       else
 276         pap_Failure(authp);
 277
 278       free(key);
 279       break;
 280
 281     case PAP_ACK:
 282       auth_StopTimer(authp);
 283       if (p->link.lcp.auth_iwait == PROTO_PAP) {
 284         p->link.lcp.auth_iwait = 0;
 285         if (p->link.lcp.auth_ineed == 0)
 286           /*
 287            * We've succeeded in our ``login''
 288            * If we're not expecting  the peer to authenticate (or he already
 289            * has), proceed to network phase.
 290            */
 291           datalink_AuthOk(p->dl);
 292       }
 293       break;
 294
 295     case PAP_NAK:
 296       auth_StopTimer(authp);
 297       datalink_AuthNotOk(p->dl);
 298       break;
 299   }
 300
 301   m_freem(bp);
 302   return NULL;
 303 }