1 /*****************************************************************************
2 * ppp.h - Network Point to Point Protocol header file.
3 *
4 * Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
5 * portions Copyright (c) 1997 Global Election Systems Inc.
6 *
7 * The authors hereby grant permission to use, copy, modify, distribute,
8 * and license this software and its documentation for any purpose, provided
9 * that existing copyright notices are retained in all copies and that this
10 * notice and the following disclaimer are included verbatim in any
11 * distributions. No written agreement, license, or royalty fee is required
12 * for any of the authorized uses.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 ******************************************************************************
26 * REVISION HISTORY
27 *
28 * 03-01-01 Marc Boucher <marc@mbsi.ca>
29 *   Ported to lwIP.
30 * 97-11-05 Guy Lancaster <glanca@gesn.com>, Global Election Systems Inc.
31 *   Original derived from BSD codes.
32 *****************************************************************************/
33 
34 #include "netif/ppp/ppp_opts.h"
35 #if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
36 
37 #ifndef PPP_H
38 #define PPP_H
39 
40 #include "lwip/def.h"
41 #include "lwip/stats.h"
42 #include "lwip/mem.h"
43 #include "lwip/netif.h"
44 #include "lwip/sys.h"
45 #include "lwip/timeouts.h"
46 #if PPP_IPV6_SUPPORT
47 #include "lwip/ip6_addr.h"
48 #endif /* PPP_IPV6_SUPPORT */
49 
50 /* Disable non-working or rarely used PPP feature, so rarely that we don't want to bloat ppp_opts.h with them */
51 #ifndef PPP_OPTIONS
52 #define PPP_OPTIONS         0
53 #endif
54 
55 #ifndef PPP_NOTIFY
56 #define PPP_NOTIFY          0
57 #endif
58 
59 #ifndef PPP_REMOTENAME
60 #define PPP_REMOTENAME      0
61 #endif
62 
63 #ifndef PPP_IDLETIMELIMIT
64 #define PPP_IDLETIMELIMIT   0
65 #endif
66 
67 #ifndef PPP_LCP_ADAPTIVE
68 #define PPP_LCP_ADAPTIVE    0
69 #endif
70 
71 #ifndef PPP_MAXCONNECT
72 #define PPP_MAXCONNECT      0
73 #endif
74 
75 #ifndef PPP_ALLOWED_ADDRS
76 #define PPP_ALLOWED_ADDRS   0
77 #endif
78 
79 #ifndef PPP_PROTOCOLNAME
80 #define PPP_PROTOCOLNAME    0
81 #endif
82 
83 #ifndef PPP_STATS_SUPPORT
84 #define PPP_STATS_SUPPORT   0
85 #endif
86 
87 #ifndef DEFLATE_SUPPORT
88 #define DEFLATE_SUPPORT     0
89 #endif
90 
91 #ifndef BSDCOMPRESS_SUPPORT
92 #define BSDCOMPRESS_SUPPORT 0
93 #endif
94 
95 #ifndef PREDICTOR_SUPPORT
96 #define PREDICTOR_SUPPORT   0
97 #endif
98 
99 /*************************
100 *** PUBLIC DEFINITIONS ***
101 *************************/
102 
103 /*
104  * The basic PPP frame.
105  */
106 #define PPP_HDRLEN	4	/* octets for standard ppp header */
107 #define PPP_FCSLEN	2	/* octets for FCS */
108 
109 /*
110  * Values for phase.
111  */
112 #define PPP_PHASE_DEAD          0
113 #define PPP_PHASE_MASTER        1
114 #define PPP_PHASE_HOLDOFF       2
115 #define PPP_PHASE_INITIALIZE    3
116 #define PPP_PHASE_SERIALCONN    4
117 #define PPP_PHASE_DORMANT       5
118 #define PPP_PHASE_ESTABLISH     6
119 #define PPP_PHASE_AUTHENTICATE  7
120 #define PPP_PHASE_CALLBACK      8
121 #define PPP_PHASE_NETWORK       9
122 #define PPP_PHASE_RUNNING       10
123 #define PPP_PHASE_TERMINATE     11
124 #define PPP_PHASE_DISCONNECT    12
125 
126 /* Error codes. */
127 #define PPPERR_NONE         0  /* No error. */
128 #define PPPERR_PARAM        1  /* Invalid parameter. */
129 #define PPPERR_OPEN         2  /* Unable to open PPP session. */
130 #define PPPERR_DEVICE       3  /* Invalid I/O device for PPP. */
131 #define PPPERR_ALLOC        4  /* Unable to allocate resources. */
132 #define PPPERR_USER         5  /* User interrupt. */
133 #define PPPERR_CONNECT      6  /* Connection lost. */
134 #define PPPERR_AUTHFAIL     7  /* Failed authentication challenge. */
135 #define PPPERR_PROTOCOL     8  /* Failed to meet protocol. */
136 #define PPPERR_PEERDEAD     9  /* Connection timeout */
137 #define PPPERR_IDLETIMEOUT  10 /* Idle Timeout */
138 #define PPPERR_CONNECTTIME  11 /* Max connect time reached */
139 #define PPPERR_LOOPBACK     12 /* Loopback detected */
140 
141 /* Whether auth support is enabled at all */
142 #define PPP_AUTH_SUPPORT (PAP_SUPPORT || CHAP_SUPPORT || EAP_SUPPORT)
143 
144 /************************
145 *** PUBLIC DATA TYPES ***
146 ************************/
147 
148 /*
149  * Other headers require ppp_pcb definition for prototypes, but ppp_pcb
150  * require some structure definition from other headers as well, we are
151  * fixing the dependency loop here by declaring the ppp_pcb type then
152  * by including headers containing necessary struct definition for ppp_pcb
153  */
154 typedef struct ppp_pcb_s ppp_pcb;
155 
156 /* Type definitions for BSD code. */
157 #ifndef __u_char_defined
158 typedef unsigned long  u_long;
159 typedef unsigned int   u_int;
160 typedef unsigned short u_short;
161 typedef unsigned char  u_char;
162 #endif
163 
164 #include "fsm.h"
165 #include "lcp.h"
166 #if CCP_SUPPORT
167 #include "ccp.h"
168 #endif /* CCP_SUPPORT */
169 #if MPPE_SUPPORT
170 #include "mppe.h"
171 #endif /* MPPE_SUPPORT */
172 #if PPP_IPV4_SUPPORT
173 #include "ipcp.h"
174 #endif /* PPP_IPV4_SUPPORT */
175 #if PPP_IPV6_SUPPORT
176 #include "ipv6cp.h"
177 #endif /* PPP_IPV6_SUPPORT */
178 #if PAP_SUPPORT
179 #include "upap.h"
180 #endif /* PAP_SUPPORT */
181 #if CHAP_SUPPORT
182 #include "chap-new.h"
183 #endif /* CHAP_SUPPORT */
184 #if EAP_SUPPORT
185 #include "eap.h"
186 #endif /* EAP_SUPPORT */
187 #if VJ_SUPPORT
188 #include "vj.h"
189 #endif /* VJ_SUPPORT */
190 
191 /* Link status callback function prototype */
192 typedef void (*ppp_link_status_cb_fn)(ppp_pcb *pcb, int err_code, void *ctx);
193 
194 /*
195  * PPP configuration.
196  */
197 typedef struct ppp_settings_s {
198 
199 #if PPP_SERVER && PPP_AUTH_SUPPORT
200   unsigned int  auth_required       :1;      /* Peer is required to authenticate */
201   unsigned int  null_login          :1;      /* Username of "" and a password of "" are acceptable */
202 #endif /* PPP_SERVER && PPP_AUTH_SUPPORT */
203 #if PPP_REMOTENAME
204   unsigned int  explicit_remote     :1;      /* remote_name specified with remotename opt */
205 #endif /* PPP_REMOTENAME */
206 #if PAP_SUPPORT
207   unsigned int  refuse_pap          :1;      /* Don't proceed auth. with PAP */
208 #endif /* PAP_SUPPORT */
209 #if CHAP_SUPPORT
210   unsigned int  refuse_chap         :1;      /* Don't proceed auth. with CHAP */
211 #endif /* CHAP_SUPPORT */
212 #if MSCHAP_SUPPORT
213   unsigned int  refuse_mschap       :1;      /* Don't proceed auth. with MS-CHAP */
214   unsigned int  refuse_mschap_v2    :1;      /* Don't proceed auth. with MS-CHAPv2 */
215 #endif /* MSCHAP_SUPPORT */
216 #if EAP_SUPPORT
217   unsigned int  refuse_eap          :1;      /* Don't proceed auth. with EAP */
218 #endif /* EAP_SUPPORT */
219 #if LWIP_DNS
220   unsigned int  usepeerdns          :1;      /* Ask peer for DNS adds */
221 #endif /* LWIP_DNS */
222   unsigned int  persist             :1;      /* Persist mode, always try to open the connection */
223 #if PRINTPKT_SUPPORT
224   unsigned int  hide_password       :1;      /* Hide password in dumped packets */
225 #endif /* PRINTPKT_SUPPORT */
226   unsigned int  noremoteip          :1;      /* Let him have no IP address */
227   unsigned int  lax_recv            :1;      /* accept control chars in asyncmap */
228   unsigned int  noendpoint          :1;      /* don't send/accept endpoint discriminator */
229 #if PPP_LCP_ADAPTIVE
230   unsigned int lcp_echo_adaptive    :1;      /* request echo only if the link was idle */
231 #endif /* PPP_LCP_ADAPTIVE */
232 #if MPPE_SUPPORT
233   unsigned int require_mppe         :1;      /* Require MPPE (Microsoft Point to Point Encryption) */
234   unsigned int refuse_mppe_40       :1;      /* Allow MPPE 40-bit mode? */
235   unsigned int refuse_mppe_128      :1;      /* Allow MPPE 128-bit mode? */
236   unsigned int refuse_mppe_stateful :1;      /* Allow MPPE stateful mode? */
237 #endif /* MPPE_SUPPORT */
238 
239   u16_t  listen_time;                 /* time to listen first (ms), waiting for peer to send LCP packet */
240 
241 #if PPP_IDLETIMELIMIT
242   u16_t  idle_time_limit;             /* Disconnect if idle for this many seconds */
243 #endif /* PPP_IDLETIMELIMIT */
244 #if PPP_MAXCONNECT
245   u32_t  maxconnect;                  /* Maximum connect time (seconds) */
246 #endif /* PPP_MAXCONNECT */
247 
248 #if PPP_AUTH_SUPPORT
249   /* auth data */
250   const char  *user;                   /* Username for PAP */
251   const char  *passwd;                 /* Password for PAP, secret for CHAP */
252 #if PPP_REMOTENAME
253   char  remote_name[MAXNAMELEN   + 1]; /* Peer's name for authentication */
254 #endif /* PPP_REMOTENAME */
255 
256 #if PAP_SUPPORT
257   u8_t  pap_timeout_time;        /* Timeout (seconds) for auth-req retrans. */
258   u8_t  pap_max_transmits;       /* Number of auth-reqs sent */
259 #if PPP_SERVER
260   u8_t  pap_req_timeout;         /* Time to wait for auth-req from peer */
261 #endif /* PPP_SERVER */
262 #endif /* PAP_SUPPPORT */
263 
264 #if CHAP_SUPPORT
265   u8_t  chap_timeout_time;       /* Timeout (seconds) for retransmitting req */
266   u8_t  chap_max_transmits;      /* max # times to send challenge */
267 #if PPP_SERVER
268   u8_t  chap_rechallenge_time;   /* Time to wait for auth-req from peer */
269 #endif /* PPP_SERVER */
270 #endif /* CHAP_SUPPPORT */
271 
272 #if EAP_SUPPORT
273   u8_t  eap_req_time;            /* Time to wait (for retransmit/fail) */
274   u8_t  eap_allow_req;           /* Max Requests allowed */
275 #if PPP_SERVER
276   u8_t  eap_timeout_time;        /* Time to wait (for retransmit/fail) */
277   u8_t  eap_max_transmits;       /* Max Requests allowed */
278 #endif /* PPP_SERVER */
279 #endif /* EAP_SUPPORT */
280 
281 #endif /* PPP_AUTH_SUPPORT */
282 
283   u8_t  fsm_timeout_time;            /* Timeout time in seconds */
284   u8_t  fsm_max_conf_req_transmits;  /* Maximum Configure-Request transmissions */
285   u8_t  fsm_max_term_transmits;      /* Maximum Terminate-Request transmissions */
286   u8_t  fsm_max_nak_loops;           /* Maximum number of nak loops tolerated */
287 
288   u8_t  lcp_loopbackfail;     /* Number of times we receive our magic number from the peer
289                                  before deciding the link is looped-back. */
290   u8_t  lcp_echo_interval;    /* Interval between LCP echo-requests */
291   u8_t  lcp_echo_fails;       /* Tolerance to unanswered echo-requests */
292 
293 } ppp_settings;
294 
295 #if PPP_SERVER
296 struct ppp_addrs {
297 #if PPP_IPV4_SUPPORT
298   ip4_addr_t our_ipaddr, his_ipaddr, netmask;
299 #if LWIP_DNS
300   ip4_addr_t dns1, dns2;
301 #endif /* LWIP_DNS */
302 #endif /* PPP_IPV4_SUPPORT */
303 #if PPP_IPV6_SUPPORT
304   ip6_addr_t our6_ipaddr, his6_ipaddr;
305 #endif /* PPP_IPV6_SUPPORT */
306 };
307 #endif /* PPP_SERVER */
308 
309 /*
310  * PPP interface control block.
311  */
312 struct ppp_pcb_s {
313   ppp_settings settings;
314   const struct link_callbacks *link_cb;
315   void *link_ctx_cb;
316   void (*link_status_cb)(ppp_pcb *pcb, int err_code, void *ctx);  /* Status change callback */
317 #if PPP_NOTIFY_PHASE
318   void (*notify_phase_cb)(ppp_pcb *pcb, u8_t phase, void *ctx);   /* Notify phase callback */
319 #endif /* PPP_NOTIFY_PHASE */
320   void *ctx_cb;                  /* Callbacks optional pointer */
321   struct netif *netif;           /* PPP interface */
322   u8_t phase;                    /* where the link is at */
323   u8_t err_code;                 /* Code indicating why interface is down. */
324 
325   /* flags */
326 #if PPP_IPV4_SUPPORT
327   unsigned int ipcp_is_open            :1; /* haven't called np_finished() */
328   unsigned int ipcp_is_up              :1; /* have called ipcp_up() */
329   unsigned int if4_up                  :1; /* True when the IPv4 interface is up. */
330 #if 0 /* UNUSED - PROXY ARP */
331   unsigned int proxy_arp_set           :1; /* Have created proxy arp entry */
332 #endif /* UNUSED - PROXY ARP */
333 #endif /* PPP_IPV4_SUPPORT */
334 #if PPP_IPV6_SUPPORT
335   unsigned int ipv6cp_is_up            :1; /* have called ip6cp_up() */
336   unsigned int if6_up                  :1; /* True when the IPv6 interface is up. */
337 #endif /* PPP_IPV6_SUPPORT */
338   unsigned int lcp_echo_timer_running  :1; /* set if a timer is running */
339 #if VJ_SUPPORT
340   unsigned int vj_enabled              :1; /* Flag indicating VJ compression enabled. */
341 #endif /* VJ_SUPPORT */
342 #if CCP_SUPPORT
343   unsigned int ccp_all_rejected        :1; /* we rejected all peer's options */
344 #endif /* CCP_SUPPORT */
345 #if MPPE_SUPPORT
346   unsigned int mppe_keys_set           :1; /* Have the MPPE keys been set? */
347 #endif /* MPPE_SUPPORT */
348 
349 #if PPP_AUTH_SUPPORT
350   /* auth data */
351 #if PPP_SERVER && defined(HAVE_MULTILINK)
352   char peer_authname[MAXNAMELEN + 1]; /* The name by which the peer authenticated itself to us. */
353 #endif /* PPP_SERVER && defined(HAVE_MULTILINK) */
354   u16_t auth_pending;        /* Records which authentication operations haven't completed yet. */
355   u16_t auth_done;           /* Records which authentication operations have been completed. */
356 
357 #if PAP_SUPPORT
358   upap_state upap;           /* PAP data */
359 #endif /* PAP_SUPPORT */
360 
361 #if CHAP_SUPPORT
362   chap_client_state chap_client;  /* CHAP client data */
363 #if PPP_SERVER
364   chap_server_state chap_server;  /* CHAP server data */
365 #endif /* PPP_SERVER */
366 #endif /* CHAP_SUPPORT */
367 
368 #if EAP_SUPPORT
369   eap_state eap;            /* EAP data */
370 #endif /* EAP_SUPPORT */
371 #endif /* PPP_AUTH_SUPPORT */
372 
373   fsm lcp_fsm;                   /* LCP fsm structure */
374   lcp_options lcp_wantoptions;   /* Options that we want to request */
375   lcp_options lcp_gotoptions;    /* Options that peer ack'd */
376   lcp_options lcp_allowoptions;  /* Options we allow peer to request */
377   lcp_options lcp_hisoptions;    /* Options that we ack'd */
378   u16_t peer_mru;                /* currently negotiated peer MRU */
379   u8_t lcp_echos_pending;        /* Number of outstanding echo msgs */
380   u8_t lcp_echo_number;          /* ID number of next echo frame */
381 
382   u8_t num_np_open;              /* Number of network protocols which we have opened. */
383   u8_t num_np_up;                /* Number of network protocols which have come up. */
384 
385 #if VJ_SUPPORT
386   struct vjcompress vj_comp;     /* Van Jacobson compression header. */
387 #endif /* VJ_SUPPORT */
388 
389 #if CCP_SUPPORT
390   fsm ccp_fsm;                   /* CCP fsm structure */
391   ccp_options ccp_wantoptions;   /* what to request the peer to use */
392   ccp_options ccp_gotoptions;    /* what the peer agreed to do */
393   ccp_options ccp_allowoptions;  /* what we'll agree to do */
394   ccp_options ccp_hisoptions;    /* what we agreed to do */
395   u8_t ccp_localstate;           /* Local state (mainly for handling reset-reqs and reset-acks). */
396   u8_t ccp_receive_method;       /* Method chosen on receive path */
397   u8_t ccp_transmit_method;      /* Method chosen on transmit path */
398 #if MPPE_SUPPORT
399   ppp_mppe_state mppe_comp;      /* MPPE "compressor" structure */
400   ppp_mppe_state mppe_decomp;    /* MPPE "decompressor" structure */
401 #endif /* MPPE_SUPPORT */
402 #endif /* CCP_SUPPORT */
403 
404 #if PPP_IPV4_SUPPORT
405   fsm ipcp_fsm;                   /* IPCP fsm structure */
406   ipcp_options ipcp_wantoptions;  /* Options that we want to request */
407   ipcp_options ipcp_gotoptions;   /* Options that peer ack'd */
408   ipcp_options ipcp_allowoptions; /* Options we allow peer to request */
409   ipcp_options ipcp_hisoptions;   /* Options that we ack'd */
410 #endif /* PPP_IPV4_SUPPORT */
411 
412 #if PPP_IPV6_SUPPORT
413   fsm ipv6cp_fsm;                     /* IPV6CP fsm structure */
414   ipv6cp_options ipv6cp_wantoptions;  /* Options that we want to request */
415   ipv6cp_options ipv6cp_gotoptions;   /* Options that peer ack'd */
416   ipv6cp_options ipv6cp_allowoptions; /* Options we allow peer to request */
417   ipv6cp_options ipv6cp_hisoptions;   /* Options that we ack'd */
418 #endif /* PPP_IPV6_SUPPORT */
419 };
420 
421 /************************
422  *** PUBLIC FUNCTIONS ***
423  ************************/
424 
425 /*
426  * WARNING: For multi-threads environment, all ppp_set_* functions most
427  * only be called while the PPP is in the dead phase (i.e. disconnected).
428  */
429 
430 #if PPP_AUTH_SUPPORT
431 /*
432  * Set PPP authentication.
433  *
434  * Warning: Using PPPAUTHTYPE_ANY might have security consequences.
435  * RFC 1994 says:
436  *
437  * In practice, within or associated with each PPP server, there is a
438  * database which associates "user" names with authentication
439  * information ("secrets").  It is not anticipated that a particular
440  * named user would be authenticated by multiple methods.  This would
441  * make the user vulnerable to attacks which negotiate the least secure
442  * method from among a set (such as PAP rather than CHAP).  If the same
443  * secret was used, PAP would reveal the secret to be used later with
444  * CHAP.
445  *
446  * Instead, for each user name there should be an indication of exactly
447  * one method used to authenticate that user name.  If a user needs to
448  * make use of different authentication methods under different
449  * circumstances, then distinct user names SHOULD be employed, each of
450  * which identifies exactly one authentication method.
451  *
452  * Default is none auth type, unset (NULL) user and passwd.
453  */
454 #define PPPAUTHTYPE_NONE      0x00
455 #define PPPAUTHTYPE_PAP       0x01
456 #define PPPAUTHTYPE_CHAP      0x02
457 #define PPPAUTHTYPE_MSCHAP    0x04
458 #define PPPAUTHTYPE_MSCHAP_V2 0x08
459 #define PPPAUTHTYPE_EAP       0x10
460 #define PPPAUTHTYPE_ANY       0xff
461 void ppp_set_auth(ppp_pcb *pcb, u8_t authtype, const char *user, const char *passwd);
462 
463 /*
464  * If set, peer is required to authenticate. This is mostly necessary for PPP server support.
465  *
466  * Default is false.
467  */
468 #define ppp_set_auth_required(ppp, boolval) (ppp->settings.auth_required = boolval)
469 #endif /* PPP_AUTH_SUPPORT */
470 
471 #if PPP_IPV4_SUPPORT
472 /*
473  * Set PPP interface "our" and "his" IPv4 addresses. This is mostly necessary for PPP server
474  * support but it can also be used on a PPP link where each side choose its own IP address.
475  *
476  * Default is unset (0.0.0.0).
477  */
478 #define ppp_set_ipcp_ouraddr(ppp, addr) (ppp->ipcp_wantoptions.ouraddr = ip4_addr_get_u32(addr))
479 #define ppp_set_ipcp_hisaddr(ppp, addr) (ppp->ipcp_wantoptions.hisaddr = ip4_addr_get_u32(addr))
480 #if LWIP_DNS
481 /*
482  * Set DNS server addresses that are sent if the peer asks for them. This is mostly necessary
483  * for PPP server support.
484  *
485  * Default is unset (0.0.0.0).
486  */
487 #define ppp_set_ipcp_dnsaddr(ppp, index, addr) (ppp->ipcp_allowoptions.dnsaddr[index] = ip4_addr_get_u32(addr))
488 
489 /*
490  * If set, we ask the peer for up to 2 DNS server addresses. Received DNS server addresses are
491  * registered using the dns_setserver() function.
492  *
493  * Default is false.
494  */
495 #define ppp_set_usepeerdns(ppp, boolval) (ppp->settings.usepeerdns = boolval)
496 #endif /* LWIP_DNS */
497 #endif /* PPP_IPV4_SUPPORT */
498 
499 #if MPPE_SUPPORT
500 /* Disable MPPE (Microsoft Point to Point Encryption). This parameter is exclusive. */
501 #define PPP_MPPE_DISABLE           0x00
502 /* Require the use of MPPE (Microsoft Point to Point Encryption). */
503 #define PPP_MPPE_ENABLE            0x01
504 /* Allow MPPE to use stateful mode. Stateless mode is still attempted first. */
505 #define PPP_MPPE_ALLOW_STATEFUL    0x02
506 /* Refuse the use of MPPE with 40-bit encryption. Conflict with PPP_MPPE_REFUSE_128. */
507 #define PPP_MPPE_REFUSE_40         0x04
508 /* Refuse the use of MPPE with 128-bit encryption. Conflict with PPP_MPPE_REFUSE_40. */
509 #define PPP_MPPE_REFUSE_128        0x08
510 /*
511  * Set MPPE configuration
512  *
513  * Default is disabled.
514  */
515 void ppp_set_mppe(ppp_pcb *pcb, u8_t flags);
516 #endif /* MPPE_SUPPORT */
517 
518 /*
519  * Wait for up to intval milliseconds for a valid PPP packet from the peer.
520  * At the end of this  time, or when a valid PPP packet is received from the
521  * peer, we commence negotiation by sending our first LCP packet.
522  *
523  * Default is 0.
524  */
525 #define ppp_set_listen_time(ppp, intval) (ppp->settings.listen_time = intval)
526 
527 /*
528  * If set, we will attempt to initiate a connection but if no reply is received from
529  * the peer, we will then just wait passively for a valid LCP packet from the peer.
530  *
531  * Default is false.
532  */
533 #define ppp_set_passive(ppp, boolval) (ppp->lcp_wantoptions.passive = boolval)
534 
535 /*
536  * If set, we will not transmit LCP packets to initiate a connection until a valid
537  * LCP packet is received from the peer. This is what we usually call the server mode.
538  *
539  * Default is false.
540  */
541 #define ppp_set_silent(ppp, boolval) (ppp->lcp_wantoptions.silent = boolval)
542 
543 /*
544  * If set, enable protocol field compression negotiation in both the receive and
545  * the transmit direction.
546  *
547  * Default is true.
548  */
549 #define ppp_set_neg_pcomp(ppp, boolval) (ppp->lcp_wantoptions.neg_pcompression = \
550                                          ppp->lcp_allowoptions.neg_pcompression = boolval)
551 
552 /*
553  * If set, enable Address/Control compression in both the receive and the transmit
554  * direction.
555  *
556  * Default is true.
557  */
558 #define ppp_set_neg_accomp(ppp, boolval) (ppp->lcp_wantoptions.neg_accompression = \
559                                           ppp->lcp_allowoptions.neg_accompression = boolval)
560 
561 /*
562  * If set, enable asyncmap negotiation. Otherwise forcing all control characters to
563  * be escaped for both the transmit and the receive direction.
564  *
565  * Default is true.
566  */
567 #define ppp_set_neg_asyncmap(ppp, boolval) (ppp->lcp_wantoptions.neg_asyncmap = \
568                                             ppp->lcp_allowoptions.neg_asyncmap = boolval)
569 
570 /*
571  * This option sets the Async-Control-Character-Map (ACCM) for this end of the link.
572  * The ACCM is a set of 32 bits, one for each of the ASCII control characters with
573  * values from 0 to 31, where a 1 bit  indicates that the corresponding control
574  * character should not be used in PPP packets sent to this system. The map is
575  * an unsigned 32 bits integer where the least significant bit (00000001) represents
576  * character 0 and the most significant bit (80000000) represents character 31.
577  * We will then ask the peer to send these characters as a 2-byte escape sequence.
578  *
579  * Default is 0.
580  */
581 #define ppp_set_asyncmap(ppp, intval) (ppp->lcp_wantoptions.asyncmap = intval)
582 
583 /*
584  * Set a PPP interface as the default network interface
585  * (used to output all packets for which no specific route is found).
586  */
587 #define ppp_set_default(ppp)         netif_set_default(ppp->netif)
588 
589 #if PPP_NOTIFY_PHASE
590 /*
591  * Set a PPP notify phase callback.
592  *
593  * This can be used for example to set a LED pattern depending on the
594  * current phase of the PPP session.
595  */
596 typedef void (*ppp_notify_phase_cb_fn)(ppp_pcb *pcb, u8_t phase, void *ctx);
597 void ppp_set_notify_phase_callback(ppp_pcb *pcb, ppp_notify_phase_cb_fn notify_phase_cb);
598 #endif /* PPP_NOTIFY_PHASE */
599 
600 /*
601  * Initiate a PPP connection.
602  *
603  * This can only be called if PPP is in the dead phase.
604  *
605  * Holdoff is the time to wait (in seconds) before initiating
606  * the connection.
607  *
608  * If this port connects to a modem, the modem connection must be
609  * established before calling this.
610  */
611 err_t ppp_connect(ppp_pcb *pcb, u16_t holdoff);
612 
613 #if PPP_SERVER
614 /*
615  * Listen for an incoming PPP connection.
616  *
617  * This can only be called if PPP is in the dead phase.
618  *
619  * If this port connects to a modem, the modem connection must be
620  * established before calling this.
621  */
622 err_t ppp_listen(ppp_pcb *pcb);
623 #endif /* PPP_SERVER */
624 
625 /*
626  * Initiate the end of a PPP connection.
627  * Any outstanding packets in the queues are dropped.
628  *
629  * Setting nocarrier to 1 close the PPP connection without initiating the
630  * shutdown procedure. Always using nocarrier = 0 is still recommended,
631  * this is going to take a little longer time if your link is down, but
632  * is a safer choice for the PPP state machine.
633  *
634  * Return 0 on success, an error code on failure.
635  */
636 err_t ppp_close(ppp_pcb *pcb, u8_t nocarrier);
637 
638 /*
639  * Release the control block.
640  *
641  * This can only be called if PPP is in the dead phase.
642  *
643  * You must use ppp_close() before if you wish to terminate
644  * an established PPP session.
645  *
646  * Return 0 on success, an error code on failure.
647  */
648 err_t ppp_free(ppp_pcb *pcb);
649 
650 /*
651  * PPP IOCTL commands.
652  *
653  * Get the up status - 0 for down, non-zero for up.  The argument must
654  * point to an int.
655  */
656 #define PPPCTLG_UPSTATUS 0
657 
658 /*
659  * Get the PPP error code.  The argument must point to an int.
660  * Returns a PPPERR_* value.
661  */
662 #define PPPCTLG_ERRCODE  1
663 
664 /*
665  * Get the fd associated with a PPP over serial
666  */
667 #define PPPCTLG_FD       2
668 
669 /*
670  * Get and set parameters for the given connection.
671  * Return 0 on success, an error code on failure.
672  */
673 err_t ppp_ioctl(ppp_pcb *pcb, u8_t cmd, void *arg);
674 
675 /* Get the PPP netif interface */
676 #define ppp_netif(ppp)               (ppp->netif)
677 
678 /* Set an lwIP-style status-callback for the selected PPP device */
679 #define ppp_set_netif_statuscallback(ppp, status_cb)       \
680         netif_set_status_callback(ppp->netif, status_cb);
681 
682 /* Set an lwIP-style link-callback for the selected PPP device */
683 #define ppp_set_netif_linkcallback(ppp, link_cb)           \
684         netif_set_link_callback(ppp->netif, link_cb);
685 
686 #endif /* PPP_H */
687 
688 #endif /* PPP_SUPPORT */
689