usr.sbin/ppp/mp.c

   1 /*-
   2  * Copyright (c) 1998 Brian Somers <brian@Awfulhak.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/usr.sbin/ppp/mp.c,v 1.36.2.9 2002/09/01 02:12:28 brian Exp $
  27  * $DragonFly: src/usr.sbin/ppp/mp.c,v 1.3 2007/05/17 08:19:03 swildner Exp $
  28  */
  29
  30 #include <sys/param.h>
  31 #include <netinet/in.h>
  32 #include <netinet/in_systm.h>
  33 #include <netinet/ip.h>
  34 #include <arpa/inet.h>
  35 #include <net/if_dl.h>
  36 #include <sys/socket.h>
  37 #include <sys/un.h>
  38
  39 #include <errno.h>
  40 #include <paths.h>
  41 #include <stdarg.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <sys/stat.h>
  46 #include <termios.h>
  47 #include <unistd.h>
  48
  49 #include "layer.h"
  50 #ifndef NONAT
  51 #include "nat_cmd.h"
  52 #endif
  53 #include "vjcomp.h"
  54 #include "ua.h"
  55 #include "defs.h"
  56 #include "command.h"
  57 #include "mbuf.h"
  58 #include "log.h"
  59 #include "timer.h"
  60 #include "fsm.h"
  61 #include "iplist.h"
  62 #include "throughput.h"
  63 #include "slcompress.h"
  64 #include "lqr.h"
  65 #include "hdlc.h"
  66 #include "ncpaddr.h"
  67 #include "ipcp.h"
  68 #include "auth.h"
  69 #include "lcp.h"
  70 #include "async.h"
  71 #include "ccp.h"
  72 #include "link.h"
  73 #include "descriptor.h"
  74 #include "physical.h"
  75 #include "chat.h"
  76 #include "proto.h"
  77 #include "filter.h"
  78 #include "mp.h"
  79 #include "chap.h"
  80 #include "cbcp.h"
  81 #include "datalink.h"
  82 #ifndef NORADIUS
  83 #include "radius.h"
  84 #endif
  85 #include "ipv6cp.h"
  86 #include "ncp.h"
  87 #include "bundle.h"
  88 #include "prompt.h"
  89 #include "id.h"
  90 #include "arp.h"
  91
  92 void
  93 peerid_Init(struct peerid *peer)
  94 {
  95   peer->enddisc.class = 0;
  96   *peer->enddisc.address = '\0';
  97   peer->enddisc.len = 0;
  98   *peer->authname = '\0';
  99 }
 100
 101 int
 102 peerid_Equal(const struct peerid *p1, const struct peerid *p2)
 103 {
 104   return !strcmp(p1->authname, p2->authname) &&
 105          p1->enddisc.class == p2->enddisc.class &&
 106          p1->enddisc.len == p2->enddisc.len &&
 107          !memcmp(p1->enddisc.address, p2->enddisc.address, p1->enddisc.len);
 108 }
 109
 110 static u_int32_t
 111 inc_seq(unsigned is12bit, u_int32_t seq)
 112 {
 113   seq++;
 114   if (is12bit) {
 115     if (seq & 0xfffff000)
 116       seq = 0;
 117   } else if (seq & 0xff000000)
 118     seq = 0;
 119   return seq;
 120 }
 121
 122 static int
 123 isbefore(unsigned is12bit, u_int32_t seq1, u_int32_t seq2)
 124 {
 125   u_int32_t max = (is12bit ? 0xfff : 0xffffff) - 0x200;
 126
 127   if (seq1 > max) {
 128     if (seq2 < 0x200 || seq2 > seq1)
 129       return 1;
 130   } else if ((seq1 > 0x200 || seq2 <= max) && seq1 < seq2)
 131     return 1;
 132
 133   return 0;
 134 }
 135
 136 static int
 137 mp_ReadHeader(struct mp *mp, struct mbuf *m, struct mp_header *header)
 138 {
 139   if (mp->local_is12bit) {
 140     u_int16_t val;
 141
 142     ua_ntohs(MBUF_CTOP(m), &val);
 143     if (val & 0x3000) {
 144       log_Printf(LogWARN, "Oops - MP header without required zero bits\n");
 145       return 0;
 146     }
 147     header->begin = val & 0x8000 ? 1 : 0;
 148     header->end = val & 0x4000 ? 1 : 0;
 149     header->seq = val & 0x0fff;
 150     return 2;
 151   } else {
 152     ua_ntohl(MBUF_CTOP(m), &header->seq);
 153     if (header->seq & 0x3f000000) {
 154       log_Printf(LogWARN, "Oops - MP header without required zero bits\n");
 155       return 0;
 156     }
 157     header->begin = header->seq & 0x80000000 ? 1 : 0;
 158     header->end = header->seq & 0x40000000 ? 1 : 0;
 159     header->seq &= 0x00ffffff;
 160     return 4;
 161   }
 162 }
 163
 164 static void
 165 mp_LayerStart(void *v, struct fsm *fp)
 166 {
 167   /* The given FSM (ccp) is about to start up ! */
 168 }
 169
 170 static void
 171 mp_LayerUp(void *v, struct fsm *fp)
 172 {
 173   /* The given fsm (ccp) is now up */
 174
 175   bundle_CalculateBandwidth(fp->bundle);        /* Against ccp_MTUOverhead */
 176 }
 177
 178 static void
 179 mp_LayerDown(void *v, struct fsm *fp)
 180 {
 181   /* The given FSM (ccp) has been told to come down */
 182 }
 183
 184 static void
 185 mp_LayerFinish(void *v, struct fsm *fp)
 186 {
 187   /* The given fsm (ccp) is now down */
 188   if (fp->state == ST_CLOSED && fp->open_mode == OPEN_PASSIVE)
 189     fsm_Open(fp);               /* CCP goes to ST_STOPPED */
 190 }
 191
 192 static void
 193 mp_UpDown(void *v)
 194 {
 195   struct mp *mp = (struct mp *)v;
 196   int percent;
 197
 198   percent = MAX(mp->link.stats.total.in.OctetsPerSecond,
 199                 mp->link.stats.total.out.OctetsPerSecond) * 800 /
 200             mp->bundle->bandwidth;
 201   if (percent >= mp->cfg.autoload.max) {
 202     log_Printf(LogDEBUG, "%d%% saturation - bring a link up ?\n", percent);
 203     bundle_AutoAdjust(mp->bundle, percent, AUTO_UP);
 204   } else if (percent <= mp->cfg.autoload.min) {
 205     log_Printf(LogDEBUG, "%d%% saturation - bring a link down ?\n", percent);
 206     bundle_AutoAdjust(mp->bundle, percent, AUTO_DOWN);
 207   }
 208 }
 209
 210 void
 211 mp_StopAutoloadTimer(struct mp *mp)
 212 {
 213   throughput_stop(&mp->link.stats.total);
 214 }
 215
 216 void
 217 mp_CheckAutoloadTimer(struct mp *mp)
 218 {
 219   if (mp->link.stats.total.SamplePeriod != mp->cfg.autoload.period) {
 220     throughput_destroy(&mp->link.stats.total);
 221     throughput_init(&mp->link.stats.total, mp->cfg.autoload.period);
 222     throughput_callback(&mp->link.stats.total, mp_UpDown, mp);
 223   }
 224
 225   if (bundle_WantAutoloadTimer(mp->bundle))
 226     throughput_start(&mp->link.stats.total, "MP throughput", 1);
 227   else
 228     mp_StopAutoloadTimer(mp);
 229 }
 230
 231 void
 232 mp_RestartAutoloadTimer(struct mp *mp)
 233 {
 234   if (mp->link.stats.total.SamplePeriod != mp->cfg.autoload.period)
 235     mp_CheckAutoloadTimer(mp);
 236   else
 237     throughput_clear(&mp->link.stats.total, THROUGHPUT_OVERALL, NULL);
 238 }
 239
 240 void
 241 mp_Init(struct mp *mp, struct bundle *bundle)
 242 {
 243   mp->peer_is12bit = mp->local_is12bit = 0;
 244   mp->peer_mrru = mp->local_mrru = 0;
 245
 246   peerid_Init(&mp->peer);
 247
 248   mp->out.seq = 0;
 249   mp->out.link = 0;
 250   mp->out.af = AF_INET;
 251   mp->seq.min_in = 0;
 252   mp->seq.next_in = 0;
 253   mp->inbufs = NULL;
 254   mp->bundle = bundle;
 255
 256   mp->link.type = LOGICAL_LINK;
 257   mp->link.name = "mp";
 258   mp->link.len = sizeof *mp;
 259
 260   mp->cfg.autoload.period = SAMPLE_PERIOD;
 261   mp->cfg.autoload.min = mp->cfg.autoload.max = 0;
 262   throughput_init(&mp->link.stats.total, mp->cfg.autoload.period);
 263   throughput_callback(&mp->link.stats.total, mp_UpDown, mp);
 264   mp->link.stats.parent = NULL;
 265   mp->link.stats.gather = 0;    /* Let the physical links gather stats */
 266   memset(mp->link.Queue, '\0', sizeof mp->link.Queue);
 267   memset(mp->link.proto_in, '\0', sizeof mp->link.proto_in);
 268   memset(mp->link.proto_out, '\0', sizeof mp->link.proto_out);
 269
 270   mp->fsmp.LayerStart = mp_LayerStart;
 271   mp->fsmp.LayerUp = mp_LayerUp;
 272   mp->fsmp.LayerDown = mp_LayerDown;
 273   mp->fsmp.LayerFinish = mp_LayerFinish;
 274   mp->fsmp.object = mp;
 275
 276   mpserver_Init(&mp->server);
 277
 278   mp->cfg.mrru = 0;
 279   mp->cfg.shortseq = NEG_ENABLED|NEG_ACCEPTED;
 280   mp->cfg.negenddisc = NEG_ENABLED|NEG_ACCEPTED;
 281   mp->cfg.enddisc.class = 0;
 282   *mp->cfg.enddisc.address = '\0';
 283   mp->cfg.enddisc.len = 0;
 284
 285   lcp_Init(&mp->link.lcp, mp->bundle, &mp->link, NULL);
 286   ccp_Init(&mp->link.ccp, mp->bundle, &mp->link, &mp->fsmp);
 287
 288   link_EmptyStack(&mp->link);
 289   link_Stack(&mp->link, &protolayer);
 290   link_Stack(&mp->link, &ccplayer);
 291   link_Stack(&mp->link, &vjlayer);
 292 #ifndef NONAT
 293   link_Stack(&mp->link, &natlayer);
 294 #endif
 295 }
 296
 297 int
 298 mp_Up(struct mp *mp, struct datalink *dl)
 299 {
 300   struct lcp *lcp = &dl->physical->link.lcp;
 301
 302   if (mp->active) {
 303     /* We're adding a link - do a last validation on our parameters */
 304     if (!peerid_Equal(&dl->peer, &mp->peer)) {
 305       log_Printf(LogPHASE, "%s: Inappropriate peer !\n", dl->name);
 306       log_Printf(LogPHASE, "  Attached to peer %s/%s\n", mp->peer.authname,
 307                  mp_Enddisc(mp->peer.enddisc.class, mp->peer.enddisc.address,
 308                             mp->peer.enddisc.len));
 309       log_Printf(LogPHASE, "  New link is peer %s/%s\n", dl->peer.authname,
 310                  mp_Enddisc(dl->peer.enddisc.class, dl->peer.enddisc.address,
 311                             dl->peer.enddisc.len));
 312       return MP_FAILED;
 313     }
 314     if (mp->local_mrru != lcp->want_mrru ||
 315         mp->peer_mrru != lcp->his_mrru ||
 316         mp->local_is12bit != lcp->want_shortseq ||
 317         mp->peer_is12bit != lcp->his_shortseq) {
 318       log_Printf(LogPHASE, "%s: Invalid MRRU/SHORTSEQ MP parameters !\n",
 319                 dl->name);
 320       return MP_FAILED;
 321     }
 322     return MP_ADDED;
 323   } else {
 324     /* First link in multilink mode */
 325
 326     mp->local_mrru = lcp->want_mrru;
 327     mp->peer_mrru = lcp->his_mrru;
 328     mp->local_is12bit = lcp->want_shortseq;
 329     mp->peer_is12bit = lcp->his_shortseq;
 330     mp->peer = dl->peer;
 331
 332     throughput_destroy(&mp->link.stats.total);
 333     throughput_init(&mp->link.stats.total, mp->cfg.autoload.period);
 334     throughput_callback(&mp->link.stats.total, mp_UpDown, mp);
 335     memset(mp->link.Queue, '\0', sizeof mp->link.Queue);
 336     memset(mp->link.proto_in, '\0', sizeof mp->link.proto_in);
 337     memset(mp->link.proto_out, '\0', sizeof mp->link.proto_out);
 338
 339     /* Tell the link who it belongs to */
 340     dl->physical->link.stats.parent = &mp->link.stats.total;
 341
 342     mp->out.seq = 0;
 343     mp->out.link = 0;
 344     mp->out.af = AF_INET;
 345     mp->seq.min_in = 0;
 346     mp->seq.next_in = 0;
 347
 348     /*
 349      * Now we create our server socket.
 350      * If it already exists, join it.  Otherwise, create and own it
 351      */
 352     switch (mpserver_Open(&mp->server, &mp->peer)) {
 353     case MPSERVER_CONNECTED:
 354       log_Printf(LogPHASE, "mp: Transfer link on %s\n",
 355                 mp->server.socket.sun_path);
 356       mp->server.send.dl = dl;          /* Defer 'till it's safe to send */
 357       return MP_LINKSENT;
 358     case MPSERVER_FAILED:
 359       return MP_FAILED;
 360     case MPSERVER_LISTENING:
 361       log_Printf(LogPHASE, "mp: Listening on %s\n", mp->server.socket.sun_path);
 362       log_Printf(LogPHASE, "    First link: %s\n", dl->name);
 363
 364       /* Re-point our NCP layers at our MP link */
 365       ncp_SetLink(&mp->bundle->ncp, &mp->link);
 366
 367       /* Our lcp's already up 'cos of the NULL parent */
 368       if (ccp_SetOpenMode(&mp->link.ccp)) {
 369         fsm_Up(&mp->link.ccp.fsm);
 370         fsm_Open(&mp->link.ccp.fsm);
 371       }
 372
 373       mp->active = 1;
 374       break;
 375     }
 376   }
 377
 378   return MP_UP;
 379 }
 380
 381 void
 382 mp_Down(struct mp *mp)
 383 {
 384   if (mp->active) {
 385     struct mbuf *next;
 386
 387     /* Stop that ! */
 388     mp_StopAutoloadTimer(mp);
 389
 390     /* Don't want any more of these */
 391     mpserver_Close(&mp->server);
 392
 393     /* CCP goes down with a bang */
 394     fsm2initial(&mp->link.ccp.fsm);
 395
 396     /* Received fragments go in the bit-bucket */
 397     while (mp->inbufs) {
 398       next = mp->inbufs->m_nextpkt;
 399       m_freem(mp->inbufs);
 400       mp->inbufs = next;
 401     }
 402
 403     peerid_Init(&mp->peer);
 404     mp->active = 0;
 405   }
 406 }
 407
 408 void
 409 mp_linkInit(struct mp_link *mplink)
 410 {
 411   mplink->seq = 0;
 412   mplink->bandwidth = 0;
 413 }
 414
 415 static void
 416 mp_Assemble(struct mp *mp, struct mbuf *m, struct physical *p)
 417 {
 418   struct mp_header mh, h;
 419   struct mbuf *q, *last;
 420   int32_t seq;
 421
 422   /*
 423    * When `m' and `p' are NULL, it means our oldest link has gone down.
 424    * We want to determine a new min, and process any intermediate stuff
 425    * as normal
 426    */
 427
 428   if (m && mp_ReadHeader(mp, m, &mh) == 0) {
 429     m_freem(m);
 430     return;
 431   }
 432
 433   if (p) {
 434     seq = p->dl->mp.seq;
 435     p->dl->mp.seq = mh.seq;
 436   } else
 437     seq = mp->seq.min_in;
 438
 439   if (mp->seq.min_in == seq) {
 440     /*
 441      * We've received new data on the link that has our min (oldest) seq.
 442      * Figure out which link now has the smallest (oldest) seq.
 443      */
 444     struct datalink *dl;
 445
 446     mp->seq.min_in = (u_int32_t)-1;
 447     for (dl = mp->bundle->links; dl; dl = dl->next)
 448       if (dl->state == DATALINK_OPEN &&
 449           (mp->seq.min_in == -1 ||
 450            isbefore(mp->local_is12bit, dl->mp.seq, mp->seq.min_in)))
 451         mp->seq.min_in = dl->mp.seq;
 452   }
 453
 454   /*
 455    * Now process as many of our fragments as we can, adding our new
 456    * fragment in as we go, and ordering with the oldest at the top of
 457    * the queue.
 458    */
 459
 460   last = NULL;
 461   seq = mp->seq.next_in;
 462   q = mp->inbufs;
 463   while (q || m) {
 464     if (!q) {
 465       if (last)
 466         last->m_nextpkt = m;
 467       else
 468         mp->inbufs = m;
 469       q = m;
 470       m = NULL;
 471       h = mh;
 472     } else {
 473       mp_ReadHeader(mp, q, &h);
 474
 475       if (m && isbefore(mp->local_is12bit, mh.seq, h.seq)) {
 476         /* Our received fragment fits in before this one, so link it in */
 477         if (last)
 478           last->m_nextpkt = m;
 479         else
 480           mp->inbufs = m;
 481         m->m_nextpkt = q;
 482         q = m;
 483         h = mh;
 484         m = NULL;
 485       }
 486     }
 487
 488     if (h.seq != seq) {
 489       /* we're missing something :-( */
 490       if (isbefore(mp->local_is12bit, seq, mp->seq.min_in)) {
 491         /* we're never gonna get it */
 492         struct mbuf *next;
 493
 494         /* Zap all older fragments */
 495         while (mp->inbufs != q) {
 496           log_Printf(LogDEBUG, "Drop frag\n");
 497           next = mp->inbufs->m_nextpkt;
 498           m_freem(mp->inbufs);
 499           mp->inbufs = next;
 500         }
 501
 502         /*
 503          * Zap everything until the next `end' fragment OR just before
 504          * the next `begin' fragment OR 'till seq.min_in - whichever
 505          * comes first.
 506          */
 507         do {
 508           mp_ReadHeader(mp, mp->inbufs, &h);
 509           if (h.begin) {
 510             /* We might be able to process this ! */
 511             h.seq--;  /* We're gonna look for fragment with h.seq+1 */
 512             break;
 513           }
 514           next = mp->inbufs->m_nextpkt;
 515           log_Printf(LogDEBUG, "Drop frag %u\n", h.seq);
 516           m_freem(mp->inbufs);
 517           mp->inbufs = next;
 518         } while (mp->inbufs && (isbefore(mp->local_is12bit, mp->seq.min_in,
 519                                          h.seq) || h.end));
 520
 521         /*
 522          * Continue processing things from here.
 523          * This deals with the possibility that we received a fragment
 524          * on the slowest link that invalidates some of our data (because
 525          * of the hole at `q'), but where there are subsequent `whole'
 526          * packets that have already been received.
 527          */
 528
 529         mp->seq.next_in = seq = inc_seq(mp->local_is12bit, h.seq);
 530         last = NULL;
 531         q = mp->inbufs;
 532       } else
 533         /* we may still receive the missing fragment */
 534         break;
 535     } else if (h.end) {
 536       /* We've got something, reassemble */
 537       struct mbuf **frag = &q;
 538       int len;
 539       u_long first = -1;
 540
 541       do {
 542         *frag = mp->inbufs;
 543         mp->inbufs = mp->inbufs->m_nextpkt;
 544         len = mp_ReadHeader(mp, *frag, &h);
 545         if (first == -1)
 546           first = h.seq;
 547         if (frag == &q && !h.begin) {
 548           log_Printf(LogWARN, "Oops - MP frag %lu should have a begin flag\n",
 549                     (u_long)h.seq);
 550           m_freem(q);
 551           q = NULL;
 552         } else if (frag != &q && h.begin) {
 553           log_Printf(LogWARN, "Oops - MP frag %lu should have an end flag\n",
 554                     (u_long)h.seq - 1);
 555           /*
 556            * Stuff our fragment back at the front of the queue and zap
 557            * our half-assembled packet.
 558            */
 559           (*frag)->m_nextpkt = mp->inbufs;
 560           mp->inbufs = *frag;
 561           *frag = NULL;
 562           m_freem(q);
 563           q = NULL;
 564           frag = &q;
 565           h.end = 0;    /* just in case it's a whole packet */
 566         } else {
 567           (*frag)->m_offset += len;
 568           (*frag)->m_len -= len;
 569           (*frag)->m_nextpkt = NULL;
 570           do
 571             frag = &(*frag)->m_next;
 572           while (*frag != NULL);
 573         }
 574       } while (!h.end);
 575
 576       if (q) {
 577         q = m_pullup(q);
 578         log_Printf(LogDEBUG, "MP: Reassembled frags %ld-%lu, length %d\n",
 579                    first, (u_long)h.seq, m_length(q));
 580         link_PullPacket(&mp->link, MBUF_CTOP(q), q->m_len, mp->bundle);
 581         m_freem(q);
 582       }
 583
 584       mp->seq.next_in = seq = inc_seq(mp->local_is12bit, h.seq);
 585       last = NULL;
 586       q = mp->inbufs;
 587     } else {
 588       /* Look for the next fragment */
 589       seq = inc_seq(mp->local_is12bit, seq);
 590       last = q;
 591       q = q->m_nextpkt;
 592     }
 593   }
 594
 595   if (m) {
 596     /* We still have to find a home for our new fragment */
 597     last = NULL;
 598     for (q = mp->inbufs; q; last = q, q = q->m_nextpkt) {
 599       mp_ReadHeader(mp, q, &h);
 600       if (isbefore(mp->local_is12bit, mh.seq, h.seq))
 601         break;
 602     }
 603     /* Our received fragment fits in here */
 604     if (last)
 605       last->m_nextpkt = m;
 606     else
 607       mp->inbufs = m;
 608     m->m_nextpkt = q;
 609   }
 610 }
 611
 612 struct mbuf *
 613 mp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
 614 {
 615   struct physical *p = link2physical(l);
 616
 617   if (!bundle->ncp.mp.active)
 618     /* Let someone else deal with it ! */
 619     return bp;
 620
 621   if (p == NULL) {
 622     log_Printf(LogWARN, "DecodePacket: Can't do MP inside MP !\n");
 623     m_freem(bp);
 624   } else {
 625     m_settype(bp, MB_MPIN);
 626     mp_Assemble(&bundle->ncp.mp, bp, p);
 627   }
 628
 629   return NULL;
 630 }
 631
 632 static void
 633 mp_Output(struct mp *mp, struct bundle *bundle, struct link *l,
 634           struct mbuf *m, u_int32_t begin, u_int32_t end)
 635 {
 636   char prepend[4];
 637
 638   /* Stuff an MP header on the front of our packet and send it */
 639
 640   if (mp->peer_is12bit) {
 641     u_int16_t val;
 642
 643     val = (begin << 15) | (end << 14) | (u_int16_t)mp->out.seq;
 644     ua_htons(&val, prepend);
 645     m = m_prepend(m, prepend, 2, 0);
 646   } else {
 647     u_int32_t val;
 648
 649     val = (begin << 31) | (end << 30) | (u_int32_t)mp->out.seq;
 650     ua_htonl(&val, prepend);
 651     m = m_prepend(m, prepend, 4, 0);
 652   }
 653   if (log_IsKept(LogDEBUG))
 654     log_Printf(LogDEBUG, "MP[frag %d]: Send %d bytes on link `%s'\n",
 655                mp->out.seq, m_length(m), l->name);
 656   mp->out.seq = inc_seq(mp->peer_is12bit, mp->out.seq);
 657
 658   if (l->ccp.fsm.state != ST_OPENED && ccp_Required(&l->ccp)) {
 659     log_Printf(LogPHASE, "%s: Not transmitting... waiting for CCP\n", l->name);
 660     return;
 661   }
 662
 663   link_PushPacket(l, m, bundle, LINK_QUEUES(l) - 1, PROTO_MP);
 664 }
 665
 666 int
 667 mp_FillPhysicalQueues(struct bundle *bundle)
 668 {
 669   struct mp *mp = &bundle->ncp.mp;
 670   struct datalink *dl, *fdl;
 671   size_t total, add, len;
 672   int thislink, nlinks, nopenlinks, sendasip;
 673   u_int32_t begin, end;
 674   struct mbuf *m, *mo;
 675   struct link *bestlink;
 676
 677   thislink = nlinks = nopenlinks = 0;
 678   for (fdl = NULL, dl = bundle->links; dl; dl = dl->next) {
 679     /* Include non-open links here as mp->out.link will stay more correct */
 680     if (!fdl) {
 681       if (thislink == mp->out.link)
 682         fdl = dl;
 683       else
 684         thislink++;
 685     }
 686     nlinks++;
 687     if (dl->state == DATALINK_OPEN)
 688       nopenlinks++;
 689   }
 690
 691   if (!fdl) {
 692     fdl = bundle->links;
 693     if (!fdl)
 694       return 0;
 695     thislink = 0;
 696   }
 697
 698   total = 0;
 699   for (dl = fdl; nlinks > 0; dl = dl->next, nlinks--, thislink++) {
 700     if (!dl) {
 701       dl = bundle->links;
 702       thislink = 0;
 703     }
 704
 705     if (dl->state != DATALINK_OPEN)
 706       continue;
 707
 708     if (dl->physical->out)
 709       /* this link has suffered a short write.  Let it continue */
 710       continue;
 711
 712     add = link_QueueLen(&dl->physical->link);
 713     if (add) {
 714       /* this link has got stuff already queued.  Let it continue */
 715       total += add;
 716       continue;
 717     }
 718
 719     if (!mp_QueueLen(mp)) {
 720       int mrutoosmall;
 721
 722       /*
 723        * If there's only a single open link in our bundle and we haven't got
 724        * MP level link compression, queue outbound traffic directly via that
 725        * link's protocol stack rather than using the MP link.  This results
 726        * in the outbound traffic going out as PROTO_IP or PROTO_IPV6 rather
 727        * than PROTO_MP.
 728        */
 729
 730       mrutoosmall = 0;
 731       sendasip = nopenlinks < 2;
 732       if (sendasip) {
 733         if (dl->physical->link.lcp.his_mru < mp->peer_mrru) {
 734           /*
 735            * Actually, forget it.  This test is done against the MRRU rather
 736            * than the packet size so that we don't end up sending some data
 737            * in MP fragments and some data in PROTO_IP packets.  That's just
 738            * too likely to upset some ppp implementations.
 739            */
 740           mrutoosmall = 1;
 741           sendasip = 0;
 742         }
 743       }
 744
 745       bestlink = sendasip ? &dl->physical->link : &mp->link;
 746       if (!ncp_PushPacket(&bundle->ncp, &mp->out.af, bestlink))
 747         break;  /* Nothing else to send */
 748
 749       if (mrutoosmall)
 750         log_Printf(LogDEBUG, "Don't send data as PROTO_IP, MRU < MRRU\n");
 751       else if (sendasip)
 752         log_Printf(LogDEBUG, "Sending data as PROTO_IP, not PROTO_MP\n");
 753
 754       if (sendasip) {
 755         add = link_QueueLen(&dl->physical->link);
 756         if (add) {
 757           /* this link has got stuff already queued.  Let it continue */
 758           total += add;
 759           continue;
 760         }
 761       }
 762     }
 763
 764     m = link_Dequeue(&mp->link);
 765     if (m) {
 766       len = m_length(m);
 767       begin = 1;
 768       end = 0;
 769
 770       while (!end) {
 771         if (dl->state == DATALINK_OPEN) {
 772           /* Write at most his_mru bytes to the physical link */
 773           if (len <= dl->physical->link.lcp.his_mru) {
 774             mo = m;
 775             end = 1;
 776             m_settype(mo, MB_MPOUT);
 777           } else {
 778             /* It's > his_mru, chop the packet (`m') into bits */
 779             mo = m_get(dl->physical->link.lcp.his_mru, MB_MPOUT);
 780             len -= mo->m_len;
 781             m = mbuf_Read(m, MBUF_CTOP(mo), mo->m_len);
 782           }
 783           mp_Output(mp, bundle, &dl->physical->link, mo, begin, end);
 784           begin = 0;
 785         }
 786
 787         if (!end) {
 788           nlinks--;
 789           dl = dl->next;
 790           if (!dl) {
 791             dl = bundle->links;
 792             thislink = 0;
 793           } else
 794             thislink++;
 795         }
 796       }
 797     }
 798   }
 799   mp->out.link = thislink;              /* Start here next time */
 800
 801   return total;
 802 }
 803
 804 int
 805 mp_SetDatalinkBandwidth(struct cmdargs const *arg)
 806 {
 807   int val;
 808
 809   if (arg->argc != arg->argn+1)
 810     return -1;
 811
 812   val = atoi(arg->argv[arg->argn]);
 813   if (val <= 0) {
 814     log_Printf(LogWARN, "The link bandwidth must be greater than zero\n");
 815     return 1;
 816   }
 817   arg->cx->mp.bandwidth = val;
 818
 819   if (arg->cx->state == DATALINK_OPEN)
 820     bundle_CalculateBandwidth(arg->bundle);
 821
 822   return 0;
 823 }
 824
 825 int
 826 mp_ShowStatus(struct cmdargs const *arg)
 827 {
 828   struct mp *mp = &arg->bundle->ncp.mp;
 829
 830   prompt_Printf(arg->prompt, "Multilink is %sactive\n", mp->active ? "" : "in");
 831   if (mp->active) {
 832     struct mbuf *m, *lm;
 833     int bufs = 0;
 834
 835     lm = NULL;
 836     prompt_Printf(arg->prompt, "Socket:         %s\n",
 837                   mp->server.socket.sun_path);
 838     for (m = mp->inbufs; m; m = m->m_nextpkt) {
 839       bufs++;
 840       lm = m;
 841     }
 842     prompt_Printf(arg->prompt, "Pending frags:  %d", bufs);
 843     if (bufs) {
 844       struct mp_header mh;
 845       unsigned long first, last;
 846
 847       first = mp_ReadHeader(mp, mp->inbufs, &mh) ? mh.seq : 0;
 848       last = mp_ReadHeader(mp, lm, &mh) ? mh.seq : 0;
 849       prompt_Printf(arg->prompt, " (Have %lu - %lu, want %lu, lowest %lu)\n",
 850                     first, last, (unsigned long)mp->seq.next_in,
 851                     (unsigned long)mp->seq.min_in);
 852       prompt_Printf(arg->prompt, "                First has %sbegin bit and "
 853                     "%send bit", mh.begin ? "" : "no ", mh.end ? "" : "no ");
 854     }
 855     prompt_Printf(arg->prompt, "\n");
 856   }
 857
 858   prompt_Printf(arg->prompt, "\nMy Side:\n");
 859   if (mp->active) {
 860     prompt_Printf(arg->prompt, " Output SEQ:    %u\n", mp->out.seq);
 861     prompt_Printf(arg->prompt, " MRRU:          %u\n", mp->local_mrru);
 862     prompt_Printf(arg->prompt, " Short Seq:     %s\n",
 863                   mp->local_is12bit ? "on" : "off");
 864   }
 865   prompt_Printf(arg->prompt, " Discriminator: %s\n",
 866                 mp_Enddisc(mp->cfg.enddisc.class, mp->cfg.enddisc.address,
 867                            mp->cfg.enddisc.len));
 868
 869   prompt_Printf(arg->prompt, "\nHis Side:\n");
 870   if (mp->active) {
 871     prompt_Printf(arg->prompt, " Auth Name:     %s\n", mp->peer.authname);
 872     prompt_Printf(arg->prompt, " Input SEQ:     %u\n", mp->seq.next_in);
 873     prompt_Printf(arg->prompt, " MRRU:          %u\n", mp->peer_mrru);
 874     prompt_Printf(arg->prompt, " Short Seq:     %s\n",
 875                   mp->peer_is12bit ? "on" : "off");
 876   }
 877   prompt_Printf(arg->prompt,   " Discriminator: %s\n",
 878                 mp_Enddisc(mp->peer.enddisc.class, mp->peer.enddisc.address,
 879                            mp->peer.enddisc.len));
 880
 881   prompt_Printf(arg->prompt, "\nDefaults:\n");
 882
 883   prompt_Printf(arg->prompt, " MRRU:          ");
 884   if (mp->cfg.mrru)
 885     prompt_Printf(arg->prompt, "%d (multilink enabled)\n", mp->cfg.mrru);
 886   else
 887     prompt_Printf(arg->prompt, "disabled\n");
 888   prompt_Printf(arg->prompt, " Short Seq:     %s\n",
 889                   command_ShowNegval(mp->cfg.shortseq));
 890   prompt_Printf(arg->prompt, " Discriminator: %s\n",
 891                   command_ShowNegval(mp->cfg.negenddisc));
 892   prompt_Printf(arg->prompt, " AutoLoad:      min %d%%, max %d%%,"
 893                 " period %d secs\n", mp->cfg.autoload.min,
 894                 mp->cfg.autoload.max, mp->cfg.autoload.period);
 895
 896   return 0;
 897 }
 898
 899 const char *
 900 mp_Enddisc(u_char c, const char *address, int len)
 901 {
 902   static char result[100];      /* Used immediately after it's returned */
 903   int f, header;
 904
 905   switch (c) {
 906     case ENDDISC_NULL:
 907       sprintf(result, "Null Class");
 908       break;
 909
 910     case ENDDISC_LOCAL:
 911       snprintf(result, sizeof result, "Local Addr: %.*s", len, address);
 912       break;
 913
 914     case ENDDISC_IP:
 915       if (len == 4)
 916         snprintf(result, sizeof result, "IP %s",
 917                  inet_ntoa(*(const struct in_addr *)address));
 918       else
 919         sprintf(result, "IP[%d] ???", len);
 920       break;
 921
 922     case ENDDISC_MAC:
 923       if (len == 6) {
 924         const u_char *m = (const u_char *)address;
 925         snprintf(result, sizeof result, "MAC %02x:%02x:%02x:%02x:%02x:%02x",
 926                  m[0], m[1], m[2], m[3], m[4], m[5]);
 927       } else
 928         sprintf(result, "MAC[%d] ???", len);
 929       break;
 930
 931     case ENDDISC_MAGIC:
 932       sprintf(result, "Magic: 0x");
 933       header = strlen(result);
 934       if (len > sizeof result - header - 1)
 935         len = sizeof result - header - 1;
 936       for (f = 0; f < len; f++)
 937         sprintf(result + header + 2 * f, "%02x", address[f]);
 938       break;
 939
 940     case ENDDISC_PSN:
 941       snprintf(result, sizeof result, "PSN: %.*s", len, address);
 942       break;
 943
 944      default:
 945       sprintf(result, "%d: ", (int)c);
 946       header = strlen(result);
 947       if (len > sizeof result - header - 1)
 948         len = sizeof result - header - 1;
 949       for (f = 0; f < len; f++)
 950         sprintf(result + header + 2 * f, "%02x", address[f]);
 951       break;
 952   }
 953   return result;
 954 }
 955
 956 int
 957 mp_SetEnddisc(struct cmdargs const *arg)
 958 {
 959   struct mp *mp = &arg->bundle->ncp.mp;
 960   struct in_addr addr;
 961
 962   switch (bundle_Phase(arg->bundle)) {
 963     case PHASE_DEAD:
 964       break;
 965     case PHASE_ESTABLISH:
 966       /* Make sure none of our links are DATALINK_LCP or greater */
 967       if (bundle_HighestState(arg->bundle) >= DATALINK_LCP) {
 968         log_Printf(LogWARN, "enddisc: Only changeable before"
 969                    " LCP negotiations\n");
 970         return 1;
 971       }
 972       break;
 973     default:
 974       log_Printf(LogWARN, "enddisc: Only changeable at phase DEAD/ESTABLISH\n");
 975       return 1;
 976   }
 977
 978   if (arg->argc == arg->argn) {
 979     mp->cfg.enddisc.class = 0;
 980     *mp->cfg.enddisc.address = '\0';
 981     mp->cfg.enddisc.len = 0;
 982   } else if (arg->argc > arg->argn) {
 983     if (!strcasecmp(arg->argv[arg->argn], "label")) {
 984       mp->cfg.enddisc.class = ENDDISC_LOCAL;
 985       strcpy(mp->cfg.enddisc.address, arg->bundle->cfg.label);
 986       mp->cfg.enddisc.len = strlen(mp->cfg.enddisc.address);
 987     } else if (!strcasecmp(arg->argv[arg->argn], "ip")) {
 988       if (arg->bundle->ncp.ipcp.my_ip.s_addr == INADDR_ANY)
 989         ncprange_getip4addr(&arg->bundle->ncp.ipcp.cfg.my_range, &addr);
 990       else
 991         addr = arg->bundle->ncp.ipcp.my_ip;
 992       memcpy(mp->cfg.enddisc.address, &addr.s_addr, sizeof addr.s_addr);
 993       mp->cfg.enddisc.class = ENDDISC_IP;
 994       mp->cfg.enddisc.len = sizeof arg->bundle->ncp.ipcp.my_ip.s_addr;
 995     } else if (!strcasecmp(arg->argv[arg->argn], "mac")) {
 996       struct sockaddr_dl hwaddr;
 997       int s;
 998
 999       if (arg->bundle->ncp.ipcp.my_ip.s_addr == INADDR_ANY)
1000         ncprange_getip4addr(&arg->bundle->ncp.ipcp.cfg.my_range, &addr);
1001       else
1002         addr = arg->bundle->ncp.ipcp.my_ip;
1003
1004       s = ID0socket(PF_INET, SOCK_DGRAM, 0);
1005       if (s < 0) {
1006         log_Printf(LogERROR, "set enddisc: socket(): %s\n", strerror(errno));
1007         return 2;
1008       }
1009       if (arp_EtherAddr(s, addr, &hwaddr, 1)) {
1010         mp->cfg.enddisc.class = ENDDISC_MAC;
1011         memcpy(mp->cfg.enddisc.address, hwaddr.sdl_data + hwaddr.sdl_nlen,
1012                hwaddr.sdl_alen);
1013         mp->cfg.enddisc.len = hwaddr.sdl_alen;
1014       } else {
1015         log_Printf(LogWARN, "set enddisc: Can't locate MAC address for %s\n",
1016                   inet_ntoa(addr));
1017         close(s);
1018         return 4;
1019       }
1020       close(s);
1021     } else if (!strcasecmp(arg->argv[arg->argn], "magic")) {
1022       int f;
1023
1024       randinit();
1025       for (f = 0; f < 20; f += sizeof(long))
1026         *(long *)(mp->cfg.enddisc.address + f) = random();
1027       mp->cfg.enddisc.class = ENDDISC_MAGIC;
1028       mp->cfg.enddisc.len = 20;
1029     } else if (!strcasecmp(arg->argv[arg->argn], "psn")) {
1030       if (arg->argc > arg->argn+1) {
1031         mp->cfg.enddisc.class = ENDDISC_PSN;
1032         strcpy(mp->cfg.enddisc.address, arg->argv[arg->argn+1]);
1033         mp->cfg.enddisc.len = strlen(mp->cfg.enddisc.address);
1034       } else {
1035         log_Printf(LogWARN, "PSN endpoint requires additional data\n");
1036         return 5;
1037       }
1038     } else {
1039       log_Printf(LogWARN, "%s: Unrecognised endpoint type\n",
1040                 arg->argv[arg->argn]);
1041       return 6;
1042     }
1043   }
1044
1045   return 0;
1046 }
1047
1048 static int
1049 mpserver_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w, fd_set *e,
1050                    int *n)
1051 {
1052   struct mpserver *s = descriptor2mpserver(d);
1053   int result;
1054
1055   result = 0;
1056   if (s->send.dl != NULL) {
1057     /* We've connect()ed */
1058     if (!link_QueueLen(&s->send.dl->physical->link) &&
1059         !s->send.dl->physical->out) {
1060       /* Only send if we've transmitted all our data (i.e. the ConfigAck) */
1061       result -= datalink_RemoveFromSet(s->send.dl, r, w, e);
1062       bundle_SendDatalink(s->send.dl, s->fd, &s->socket);
1063       s->send.dl = NULL;
1064       s->fd = -1;
1065     } else
1066       /* Never read from a datalink that's on death row ! */
1067       result -= datalink_RemoveFromSet(s->send.dl, r, NULL, NULL);
1068   } else if (r && s->fd >= 0) {
1069     if (*n < s->fd + 1)
1070       *n = s->fd + 1;
1071     FD_SET(s->fd, r);
1072     log_Printf(LogTIMER, "mp: fdset(r) %d\n", s->fd);
1073     result++;
1074   }
1075   return result;
1076 }
1077
1078 static int
1079 mpserver_IsSet(struct fdescriptor *d, const fd_set *fdset)
1080 {
1081   struct mpserver *s = descriptor2mpserver(d);
1082   return s->fd >= 0 && FD_ISSET(s->fd, fdset);
1083 }
1084
1085 static void
1086 mpserver_Read(struct fdescriptor *d, struct bundle *bundle, const fd_set *fdset)
1087 {
1088   struct mpserver *s = descriptor2mpserver(d);
1089
1090   bundle_ReceiveDatalink(bundle, s->fd);
1091 }
1092
1093 static int
1094 mpserver_Write(struct fdescriptor *d, struct bundle *bundle,
1095                const fd_set *fdset)
1096 {
1097   /* We never want to write here ! */
1098   log_Printf(LogALERT, "mpserver_Write: Internal error: Bad call !\n");
1099   return 0;
1100 }
1101
1102 void
1103 mpserver_Init(struct mpserver *s)
1104 {
1105   s->desc.type = MPSERVER_DESCRIPTOR;
1106   s->desc.UpdateSet = mpserver_UpdateSet;
1107   s->desc.IsSet = mpserver_IsSet;
1108   s->desc.Read = mpserver_Read;
1109   s->desc.Write = mpserver_Write;
1110   s->send.dl = NULL;
1111   s->fd = -1;
1112   memset(&s->socket, '\0', sizeof s->socket);
1113 }
1114
1115 int
1116 mpserver_Open(struct mpserver *s, struct peerid *peer)
1117 {
1118   int f, l;
1119   mode_t mask;
1120
1121   if (s->fd != -1) {
1122     log_Printf(LogALERT, "Internal error !  mpserver already open\n");
1123     mpserver_Close(s);
1124   }
1125
1126   l = snprintf(s->socket.sun_path, sizeof s->socket.sun_path, "%sppp-%s-%02x-",
1127                _PATH_VARRUN, peer->authname, peer->enddisc.class);
1128   if (l < 0) {
1129     log_Printf(LogERROR, "mpserver: snprintf(): %s\n", strerror(errno));
1130     return MPSERVER_FAILED;
1131   }
1132
1133   for (f = 0; f < peer->enddisc.len && l < sizeof s->socket.sun_path - 2; f++) {
1134     snprintf(s->socket.sun_path + l, sizeof s->socket.sun_path - l,
1135              "%02x", *(u_char *)(peer->enddisc.address+f));
1136     l += 2;
1137   }
1138
1139   s->socket.sun_family = AF_LOCAL;
1140   s->socket.sun_len = sizeof s->socket;
1141   s->fd = ID0socket(PF_LOCAL, SOCK_DGRAM, 0);
1142   if (s->fd < 0) {
1143     log_Printf(LogERROR, "mpserver: socket(): %s\n", strerror(errno));
1144     return MPSERVER_FAILED;
1145   }
1146
1147   setsockopt(s->fd, SOL_SOCKET, SO_REUSEADDR, (struct sockaddr *)&s->socket,
1148              sizeof s->socket);
1149   mask = umask(0177);
1150
1151   /*
1152    * Try to bind the socket.  If we succeed we play server, if we fail
1153    * we connect() and hand the link off.
1154    */
1155
1156   if (ID0bind_un(s->fd, &s->socket) < 0) {
1157     if (errno != EADDRINUSE) {
1158       log_Printf(LogPHASE, "mpserver: can't create bundle socket %s (%s)\n",
1159                 s->socket.sun_path, strerror(errno));
1160       umask(mask);
1161       close(s->fd);
1162       s->fd = -1;
1163       return MPSERVER_FAILED;
1164     }
1165
1166     /* So we're the sender */
1167     umask(mask);
1168     if (ID0connect_un(s->fd, &s->socket) < 0) {
1169       log_Printf(LogPHASE, "mpserver: can't connect to bundle socket %s (%s)\n",
1170                 s->socket.sun_path, strerror(errno));
1171       if (errno == ECONNREFUSED)
1172         log_Printf(LogPHASE, "          The previous server died badly !\n");
1173       close(s->fd);
1174       s->fd = -1;
1175       return MPSERVER_FAILED;
1176     }
1177
1178     /* Donate our link to the other guy */
1179     return MPSERVER_CONNECTED;
1180   }
1181
1182   return MPSERVER_LISTENING;
1183 }
1184
1185 void
1186 mpserver_Close(struct mpserver *s)
1187 {
1188   if (s->send.dl != NULL) {
1189     bundle_SendDatalink(s->send.dl, s->fd, &s->socket);
1190     s->send.dl = NULL;
1191     s->fd = -1;
1192   } else if (s->fd >= 0) {
1193     close(s->fd);
1194     if (ID0unlink(s->socket.sun_path) == -1)
1195       log_Printf(LogERROR, "%s: Failed to remove: %s\n", s->socket.sun_path,
1196                 strerror(errno));
1197     memset(&s->socket, '\0', sizeof s->socket);
1198     s->fd = -1;
1199   }
1200 }
1201
1202 void
1203 mp_LinkLost(struct mp *mp, struct datalink *dl)
1204 {
1205   if (mp->seq.min_in == dl->mp.seq)
1206     /* We've lost the link that's holding everything up ! */
1207     mp_Assemble(mp, NULL, NULL);
1208 }
1209
1210 size_t
1211 mp_QueueLen(struct mp *mp)
1212 {
1213   return link_QueueLen(&mp->link);
1214 }