minix/lib/liblwip/dist/src/netif/ppp/upap.c

   1 /*
   2  * upap.c - User/Password Authentication Protocol.
   3  *
   4  * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  *
  18  * 3. The name "Carnegie Mellon University" must not be used to
  19  *    endorse or promote products derived from this software without
  20  *    prior written permission. For permission or any legal
  21  *    details, please contact
  22  *      Office of Technology Transfer
  23  *      Carnegie Mellon University
  24  *      5000 Forbes Avenue
  25  *      Pittsburgh, PA  15213-3890
  26  *      (412) 268-4387, fax: (412) 268-7395
  27  *      tech-transfer@andrew.cmu.edu
  28  *
  29  * 4. Redistributions of any form whatsoever must retain the following
  30  *    acknowledgment:
  31  *    "This product includes software developed by Computing Services
  32  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
  33  *
  34  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
  35  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  36  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
  37  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  38  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
  39  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  40  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  41  */
  42
  43 #include "netif/ppp/ppp_opts.h"
  44 #if PPP_SUPPORT && PAP_SUPPORT  /* don't build if not configured for use in lwipopts.h */
  45
  46 /*
  47  * @todo:
  48  */
  49
  50 #if 0 /* UNUSED */
  51 #include <stdio.h>
  52 #include <string.h>
  53 #endif /* UNUSED */
  54
  55 #include "netif/ppp/ppp_impl.h"
  56
  57 #include "netif/ppp/upap.h"
  58
  59 #if PPP_OPTIONS
  60 /*
  61  * Command-line options.
  62  */
  63 static option_t pap_option_list[] = {
  64     { "hide-password", o_bool, &hide_password,
  65       "Don't output passwords to log", OPT_PRIO | 1 },
  66     { "show-password", o_bool, &hide_password,
  67       "Show password string in debug log messages", OPT_PRIOSUB | 0 },
  68
  69     { "pap-restart", o_int, &upap[0].us_timeouttime,
  70       "Set retransmit timeout for PAP", OPT_PRIO },
  71     { "pap-max-authreq", o_int, &upap[0].us_maxtransmits,
  72       "Set max number of transmissions for auth-reqs", OPT_PRIO },
  73     { "pap-timeout", o_int, &upap[0].us_reqtimeout,
  74       "Set time limit for peer PAP authentication", OPT_PRIO },
  75
  76     { NULL }
  77 };
  78 #endif /* PPP_OPTIONS */
  79
  80 /*
  81  * Protocol entry points.
  82  */
  83 static void upap_init(ppp_pcb *pcb);
  84 static void upap_lowerup(ppp_pcb *pcb);
  85 static void upap_lowerdown(ppp_pcb *pcb);
  86 static void upap_input(ppp_pcb *pcb, u_char *inpacket, int l);
  87 static void upap_protrej(ppp_pcb *pcb);
  88 #if PRINTPKT_SUPPORT
  89 static int upap_printpkt(const u_char *p, int plen, void (*printer) (void *, const char *, ...), void *arg);
  90 #endif /* PRINTPKT_SUPPORT */
  91
  92 const struct protent pap_protent = {
  93     PPP_PAP,
  94     upap_init,
  95     upap_input,
  96     upap_protrej,
  97     upap_lowerup,
  98     upap_lowerdown,
  99     NULL,
 100     NULL,
 101 #if PRINTPKT_SUPPORT
 102     upap_printpkt,
 103 #endif /* PRINTPKT_SUPPORT */
 104 #if PPP_DATAINPUT
 105     NULL,
 106 #endif /* PPP_DATAINPUT */
 107 #if PRINTPKT_SUPPORT
 108     "PAP",
 109     NULL,
 110 #endif /* PRINTPKT_SUPPORT */
 111 #if PPP_OPTIONS
 112     pap_option_list,
 113     NULL,
 114 #endif /* PPP_OPTIONS */
 115 #if DEMAND_SUPPORT
 116     NULL,
 117     NULL
 118 #endif /* DEMAND_SUPPORT */
 119 };
 120
 121 static void upap_timeout(void *arg);
 122 #if PPP_SERVER
 123 static void upap_reqtimeout(void *arg);
 124 static void upap_rauthreq(ppp_pcb *pcb, u_char *inp, int id, int len);
 125 #endif /* PPP_SERVER */
 126 static void upap_rauthack(ppp_pcb *pcb, u_char *inp, int id, int len);
 127 static void upap_rauthnak(ppp_pcb *pcb, u_char *inp, int id, int len);
 128 static void upap_sauthreq(ppp_pcb *pcb);
 129 #if PPP_SERVER
 130 static void upap_sresp(ppp_pcb *pcb, u_char code, u_char id, const char *msg, int msglen);
 131 #endif /* PPP_SERVER */
 132
 133
 134 /*
 135  * upap_init - Initialize a UPAP unit.
 136  */
 137 static void upap_init(ppp_pcb *pcb) {
 138     pcb->upap.us_user = NULL;
 139     pcb->upap.us_userlen = 0;
 140     pcb->upap.us_passwd = NULL;
 141     pcb->upap.us_passwdlen = 0;
 142     pcb->upap.us_clientstate = UPAPCS_INITIAL;
 143 #if PPP_SERVER
 144     pcb->upap.us_serverstate = UPAPSS_INITIAL;
 145 #endif /* PPP_SERVER */
 146     pcb->upap.us_id = 0;
 147 }
 148
 149
 150 /*
 151  * upap_authwithpeer - Authenticate us with our peer (start client).
 152  *
 153  * Set new state and send authenticate's.
 154  */
 155 void upap_authwithpeer(ppp_pcb *pcb, const char *user, const char *password) {
 156
 157     if(!user || !password)
 158         return;
 159
 160     /* Save the username and password we're given */
 161     pcb->upap.us_user = user;
 162     pcb->upap.us_userlen = LWIP_MIN(strlen(user), 0xff);
 163     pcb->upap.us_passwd = password;
 164     pcb->upap.us_passwdlen = LWIP_MIN(strlen(password), 0xff);
 165     pcb->upap.us_transmits = 0;
 166
 167     /* Lower layer up yet? */
 168     if (pcb->upap.us_clientstate == UPAPCS_INITIAL ||
 169         pcb->upap.us_clientstate == UPAPCS_PENDING) {
 170         pcb->upap.us_clientstate = UPAPCS_PENDING;
 171         return;
 172     }
 173
 174     upap_sauthreq(pcb);         /* Start protocol */
 175 }
 176
 177 #if PPP_SERVER
 178 /*
 179  * upap_authpeer - Authenticate our peer (start server).
 180  *
 181  * Set new state.
 182  */
 183 void upap_authpeer(ppp_pcb *pcb) {
 184
 185     /* Lower layer up yet? */
 186     if (pcb->upap.us_serverstate == UPAPSS_INITIAL ||
 187         pcb->upap.us_serverstate == UPAPSS_PENDING) {
 188         pcb->upap.us_serverstate = UPAPSS_PENDING;
 189         return;
 190     }
 191
 192     pcb->upap.us_serverstate = UPAPSS_LISTEN;
 193     if (pcb->settings.pap_req_timeout > 0)
 194         TIMEOUT(upap_reqtimeout, pcb, pcb->settings.pap_req_timeout);
 195 }
 196 #endif /* PPP_SERVER */
 197
 198 /*
 199  * upap_timeout - Retransmission timer for sending auth-reqs expired.
 200  */
 201 static void upap_timeout(void *arg) {
 202     ppp_pcb *pcb = (ppp_pcb*)arg;
 203
 204     if (pcb->upap.us_clientstate != UPAPCS_AUTHREQ)
 205         return;
 206
 207     if (pcb->upap.us_transmits >= pcb->settings.pap_max_transmits) {
 208         /* give up in disgust */
 209         ppp_error("No response to PAP authenticate-requests");
 210         pcb->upap.us_clientstate = UPAPCS_BADAUTH;
 211         auth_withpeer_fail(pcb, PPP_PAP);
 212         return;
 213     }
 214
 215     upap_sauthreq(pcb);         /* Send Authenticate-Request */
 216 }
 217
 218
 219 #if PPP_SERVER
 220 /*
 221  * upap_reqtimeout - Give up waiting for the peer to send an auth-req.
 222  */
 223 static void upap_reqtimeout(void *arg) {
 224     ppp_pcb *pcb = (ppp_pcb*)arg;
 225
 226     if (pcb->upap.us_serverstate != UPAPSS_LISTEN)
 227         return;                 /* huh?? */
 228
 229     auth_peer_fail(pcb, PPP_PAP);
 230     pcb->upap.us_serverstate = UPAPSS_BADAUTH;
 231 }
 232 #endif /* PPP_SERVER */
 233
 234
 235 /*
 236  * upap_lowerup - The lower layer is up.
 237  *
 238  * Start authenticating if pending.
 239  */
 240 static void upap_lowerup(ppp_pcb *pcb) {
 241
 242     if (pcb->upap.us_clientstate == UPAPCS_INITIAL)
 243         pcb->upap.us_clientstate = UPAPCS_CLOSED;
 244     else if (pcb->upap.us_clientstate == UPAPCS_PENDING) {
 245         upap_sauthreq(pcb);     /* send an auth-request */
 246     }
 247
 248 #if PPP_SERVER
 249     if (pcb->upap.us_serverstate == UPAPSS_INITIAL)
 250         pcb->upap.us_serverstate = UPAPSS_CLOSED;
 251     else if (pcb->upap.us_serverstate == UPAPSS_PENDING) {
 252         pcb->upap.us_serverstate = UPAPSS_LISTEN;
 253         if (pcb->settings.pap_req_timeout > 0)
 254             TIMEOUT(upap_reqtimeout, pcb, pcb->settings.pap_req_timeout);
 255     }
 256 #endif /* PPP_SERVER */
 257 }
 258
 259
 260 /*
 261  * upap_lowerdown - The lower layer is down.
 262  *
 263  * Cancel all timeouts.
 264  */
 265 static void upap_lowerdown(ppp_pcb *pcb) {
 266
 267     if (pcb->upap.us_clientstate == UPAPCS_AUTHREQ)     /* Timeout pending? */
 268         UNTIMEOUT(upap_timeout, pcb);           /* Cancel timeout */
 269 #if PPP_SERVER
 270     if (pcb->upap.us_serverstate == UPAPSS_LISTEN && pcb->settings.pap_req_timeout > 0)
 271         UNTIMEOUT(upap_reqtimeout, pcb);
 272 #endif /* PPP_SERVER */
 273
 274     pcb->upap.us_clientstate = UPAPCS_INITIAL;
 275 #if PPP_SERVER
 276     pcb->upap.us_serverstate = UPAPSS_INITIAL;
 277 #endif /* PPP_SERVER */
 278 }
 279
 280
 281 /*
 282  * upap_protrej - Peer doesn't speak this protocol.
 283  *
 284  * This shouldn't happen.  In any case, pretend lower layer went down.
 285  */
 286 static void upap_protrej(ppp_pcb *pcb) {
 287
 288     if (pcb->upap.us_clientstate == UPAPCS_AUTHREQ) {
 289         ppp_error("PAP authentication failed due to protocol-reject");
 290         auth_withpeer_fail(pcb, PPP_PAP);
 291     }
 292 #if PPP_SERVER
 293     if (pcb->upap.us_serverstate == UPAPSS_LISTEN) {
 294         ppp_error("PAP authentication of peer failed (protocol-reject)");
 295         auth_peer_fail(pcb, PPP_PAP);
 296     }
 297 #endif /* PPP_SERVER */
 298     upap_lowerdown(pcb);
 299 }
 300
 301
 302 /*
 303  * upap_input - Input UPAP packet.
 304  */
 305 static void upap_input(ppp_pcb *pcb, u_char *inpacket, int l) {
 306     u_char *inp;
 307     u_char code, id;
 308     int len;
 309
 310     /*
 311      * Parse header (code, id and length).
 312      * If packet too short, drop it.
 313      */
 314     inp = inpacket;
 315     if (l < UPAP_HEADERLEN) {
 316         UPAPDEBUG(("pap_input: rcvd short header."));
 317         return;
 318     }
 319     GETCHAR(code, inp);
 320     GETCHAR(id, inp);
 321     GETSHORT(len, inp);
 322     if (len < UPAP_HEADERLEN) {
 323         UPAPDEBUG(("pap_input: rcvd illegal length."));
 324         return;
 325     }
 326     if (len > l) {
 327         UPAPDEBUG(("pap_input: rcvd short packet."));
 328         return;
 329     }
 330     len -= UPAP_HEADERLEN;
 331
 332     /*
 333      * Action depends on code.
 334      */
 335     switch (code) {
 336     case UPAP_AUTHREQ:
 337 #if PPP_SERVER
 338         upap_rauthreq(pcb, inp, id, len);
 339 #endif /* PPP_SERVER */
 340         break;
 341
 342     case UPAP_AUTHACK:
 343         upap_rauthack(pcb, inp, id, len);
 344         break;
 345
 346     case UPAP_AUTHNAK:
 347         upap_rauthnak(pcb, inp, id, len);
 348         break;
 349
 350     default:                            /* XXX Need code reject */
 351         break;
 352     }
 353 }
 354
 355 #if PPP_SERVER
 356 /*
 357  * upap_rauth - Receive Authenticate.
 358  */
 359 static void upap_rauthreq(ppp_pcb *pcb, u_char *inp, int id, int len) {
 360     u_char ruserlen, rpasswdlen;
 361     char *ruser;
 362     char *rpasswd;
 363     char rhostname[256];
 364     int retcode;
 365     const char *msg;
 366     int msglen;
 367
 368     if (pcb->upap.us_serverstate < UPAPSS_LISTEN)
 369         return;
 370
 371     /*
 372      * If we receive a duplicate authenticate-request, we are
 373      * supposed to return the same status as for the first request.
 374      */
 375     if (pcb->upap.us_serverstate == UPAPSS_OPEN) {
 376         upap_sresp(pcb, UPAP_AUTHACK, id, "", 0);       /* return auth-ack */
 377         return;
 378     }
 379     if (pcb->upap.us_serverstate == UPAPSS_BADAUTH) {
 380         upap_sresp(pcb, UPAP_AUTHNAK, id, "", 0);       /* return auth-nak */
 381         return;
 382     }
 383
 384     /*
 385      * Parse user/passwd.
 386      */
 387     if (len < 1) {
 388         UPAPDEBUG(("pap_rauth: rcvd short packet."));
 389         return;
 390     }
 391     GETCHAR(ruserlen, inp);
 392     len -= sizeof (u_char) + ruserlen + sizeof (u_char);
 393     if (len < 0) {
 394         UPAPDEBUG(("pap_rauth: rcvd short packet."));
 395         return;
 396     }
 397     ruser = (char *) inp;
 398     INCPTR(ruserlen, inp);
 399     GETCHAR(rpasswdlen, inp);
 400     if (len < rpasswdlen) {
 401         UPAPDEBUG(("pap_rauth: rcvd short packet."));
 402         return;
 403     }
 404
 405     rpasswd = (char *) inp;
 406
 407     /*
 408      * Check the username and password given.
 409      */
 410     retcode = UPAP_AUTHNAK;
 411     if (auth_check_passwd(pcb, ruser, ruserlen, rpasswd, rpasswdlen, &msg, &msglen)) {
 412       retcode = UPAP_AUTHACK;
 413     }
 414     BZERO(rpasswd, rpasswdlen);
 415
 416 #if 0 /* UNUSED */
 417     /*
 418      * Check remote number authorization.  A plugin may have filled in
 419      * the remote number or added an allowed number, and rather than
 420      * return an authenticate failure, is leaving it for us to verify.
 421      */
 422     if (retcode == UPAP_AUTHACK) {
 423         if (!auth_number()) {
 424             /* We do not want to leak info about the pap result. */
 425             retcode = UPAP_AUTHNAK; /* XXX exit value will be "wrong" */
 426             warn("calling number %q is not authorized", remote_number);
 427         }
 428     }
 429
 430     msglen = strlen(msg);
 431     if (msglen > 255)
 432         msglen = 255;
 433 #endif /* UNUSED */
 434
 435     upap_sresp(pcb, retcode, id, msg, msglen);
 436
 437     /* Null terminate and clean remote name. */
 438     ppp_slprintf(rhostname, sizeof(rhostname), "%.*v", ruserlen, ruser);
 439
 440     if (retcode == UPAP_AUTHACK) {
 441         pcb->upap.us_serverstate = UPAPSS_OPEN;
 442         ppp_notice("PAP peer authentication succeeded for %q", rhostname);
 443         auth_peer_success(pcb, PPP_PAP, 0, ruser, ruserlen);
 444     } else {
 445         pcb->upap.us_serverstate = UPAPSS_BADAUTH;
 446         ppp_warn("PAP peer authentication failed for %q", rhostname);
 447         auth_peer_fail(pcb, PPP_PAP);
 448     }
 449
 450     if (pcb->settings.pap_req_timeout > 0)
 451         UNTIMEOUT(upap_reqtimeout, pcb);
 452 }
 453 #endif /* PPP_SERVER */
 454
 455 /*
 456  * upap_rauthack - Receive Authenticate-Ack.
 457  */
 458 static void upap_rauthack(ppp_pcb *pcb, u_char *inp, int id, int len) {
 459     u_char msglen;
 460     char *msg;
 461     LWIP_UNUSED_ARG(id);
 462
 463     if (pcb->upap.us_clientstate != UPAPCS_AUTHREQ) /* XXX */
 464         return;
 465
 466     /*
 467      * Parse message.
 468      */
 469     if (len < 1) {
 470         UPAPDEBUG(("pap_rauthack: ignoring missing msg-length."));
 471     } else {
 472         GETCHAR(msglen, inp);
 473         if (msglen > 0) {
 474             len -= sizeof (u_char);
 475             if (len < msglen) {
 476                 UPAPDEBUG(("pap_rauthack: rcvd short packet."));
 477                 return;
 478             }
 479             msg = (char *) inp;
 480             PRINTMSG(msg, msglen);
 481         }
 482     }
 483
 484     pcb->upap.us_clientstate = UPAPCS_OPEN;
 485
 486     auth_withpeer_success(pcb, PPP_PAP, 0);
 487 }
 488
 489
 490 /*
 491  * upap_rauthnak - Receive Authenticate-Nak.
 492  */
 493 static void upap_rauthnak(ppp_pcb *pcb, u_char *inp, int id, int len) {
 494     u_char msglen;
 495     char *msg;
 496     LWIP_UNUSED_ARG(id);
 497
 498     if (pcb->upap.us_clientstate != UPAPCS_AUTHREQ) /* XXX */
 499         return;
 500
 501     /*
 502      * Parse message.
 503      */
 504     if (len < 1) {
 505         UPAPDEBUG(("pap_rauthnak: ignoring missing msg-length."));
 506     } else {
 507         GETCHAR(msglen, inp);
 508         if (msglen > 0) {
 509             len -= sizeof (u_char);
 510             if (len < msglen) {
 511                 UPAPDEBUG(("pap_rauthnak: rcvd short packet."));
 512                 return;
 513             }
 514             msg = (char *) inp;
 515             PRINTMSG(msg, msglen);
 516         }
 517     }
 518
 519     pcb->upap.us_clientstate = UPAPCS_BADAUTH;
 520
 521     ppp_error("PAP authentication failed");
 522     auth_withpeer_fail(pcb, PPP_PAP);
 523 }
 524
 525
 526 /*
 527  * upap_sauthreq - Send an Authenticate-Request.
 528  */
 529 static void upap_sauthreq(ppp_pcb *pcb) {
 530     struct pbuf *p;
 531     u_char *outp;
 532     int outlen;
 533
 534     outlen = UPAP_HEADERLEN + 2 * sizeof (u_char) +
 535         pcb->upap.us_userlen + pcb->upap.us_passwdlen;
 536     p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN +outlen), PPP_CTRL_PBUF_TYPE);
 537     if(NULL == p)
 538         return;
 539     if(p->tot_len != p->len) {
 540         pbuf_free(p);
 541         return;
 542     }
 543
 544     outp = (u_char*)p->payload;
 545     MAKEHEADER(outp, PPP_PAP);
 546
 547     PUTCHAR(UPAP_AUTHREQ, outp);
 548     PUTCHAR(++pcb->upap.us_id, outp);
 549     PUTSHORT(outlen, outp);
 550     PUTCHAR(pcb->upap.us_userlen, outp);
 551     MEMCPY(outp, pcb->upap.us_user, pcb->upap.us_userlen);
 552     INCPTR(pcb->upap.us_userlen, outp);
 553     PUTCHAR(pcb->upap.us_passwdlen, outp);
 554     MEMCPY(outp, pcb->upap.us_passwd, pcb->upap.us_passwdlen);
 555
 556     ppp_write(pcb, p);
 557
 558     TIMEOUT(upap_timeout, pcb, pcb->settings.pap_timeout_time);
 559     ++pcb->upap.us_transmits;
 560     pcb->upap.us_clientstate = UPAPCS_AUTHREQ;
 561 }
 562
 563 #if PPP_SERVER
 564 /*
 565  * upap_sresp - Send a response (ack or nak).
 566  */
 567 static void upap_sresp(ppp_pcb *pcb, u_char code, u_char id, const char *msg, int msglen) {
 568     struct pbuf *p;
 569     u_char *outp;
 570     int outlen;
 571
 572     outlen = UPAP_HEADERLEN + sizeof (u_char) + msglen;
 573     p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN +outlen), PPP_CTRL_PBUF_TYPE);
 574     if(NULL == p)
 575         return;
 576     if(p->tot_len != p->len) {
 577         pbuf_free(p);
 578         return;
 579     }
 580
 581     outp = (u_char*)p->payload;
 582     MAKEHEADER(outp, PPP_PAP);
 583
 584     PUTCHAR(code, outp);
 585     PUTCHAR(id, outp);
 586     PUTSHORT(outlen, outp);
 587     PUTCHAR(msglen, outp);
 588     MEMCPY(outp, msg, msglen);
 589
 590     ppp_write(pcb, p);
 591 }
 592 #endif /* PPP_SERVER */
 593
 594 #if PRINTPKT_SUPPORT
 595 /*
 596  * upap_printpkt - print the contents of a PAP packet.
 597  */
 598 static const char* const upap_codenames[] = {
 599     "AuthReq", "AuthAck", "AuthNak"
 600 };
 601
 602 static int upap_printpkt(const u_char *p, int plen, void (*printer) (void *, const char *, ...), void *arg) {
 603     int code, id, len;
 604     int mlen, ulen, wlen;
 605     const u_char *user, *pwd, *msg;
 606     const u_char *pstart;
 607
 608     if (plen < UPAP_HEADERLEN)
 609         return 0;
 610     pstart = p;
 611     GETCHAR(code, p);
 612     GETCHAR(id, p);
 613     GETSHORT(len, p);
 614     if (len < UPAP_HEADERLEN || len > plen)
 615         return 0;
 616
 617     if (code >= 1 && code <= (int)LWIP_ARRAYSIZE(upap_codenames))
 618         printer(arg, " %s", upap_codenames[code-1]);
 619     else
 620         printer(arg, " code=0x%x", code);
 621     printer(arg, " id=0x%x", id);
 622     len -= UPAP_HEADERLEN;
 623     switch (code) {
 624     case UPAP_AUTHREQ:
 625         if (len < 1)
 626             break;
 627         ulen = p[0];
 628         if (len < ulen + 2)
 629             break;
 630         wlen = p[ulen + 1];
 631         if (len < ulen + wlen + 2)
 632             break;
 633         user = (const u_char *) (p + 1);
 634         pwd = (const u_char *) (p + ulen + 2);
 635         p += ulen + wlen + 2;
 636         len -= ulen + wlen + 2;
 637         printer(arg, " user=");
 638         ppp_print_string(user, ulen, printer, arg);
 639         printer(arg, " password=");
 640 /* FIXME: require ppp_pcb struct as printpkt() argument */
 641 #if 0
 642         if (!pcb->settings.hide_password)
 643 #endif
 644             ppp_print_string(pwd, wlen, printer, arg);
 645 #if 0
 646         else
 647             printer(arg, "<hidden>");
 648 #endif
 649         break;
 650     case UPAP_AUTHACK:
 651     case UPAP_AUTHNAK:
 652         if (len < 1)
 653             break;
 654         mlen = p[0];
 655         if (len < mlen + 1)
 656             break;
 657         msg = (const u_char *) (p + 1);
 658         p += mlen + 1;
 659         len -= mlen + 1;
 660         printer(arg, " ");
 661         ppp_print_string(msg, mlen, printer, arg);
 662         break;
 663     default:
 664         break;
 665     }
 666
 667     /* print the rest of the bytes in the packet */
 668     for (; len > 0; --len) {
 669         GETCHAR(code, p);
 670         printer(arg, " %.2x", code);
 671     }
 672
 673     return p - pstart;
 674 }
 675 #endif /* PRINTPKT_SUPPORT */
 676
 677 #endif /* PPP_SUPPORT && PAP_SUPPORT */