5 * Main header file for TrIPE
7 * (c) 2001 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Trivial IP Encryption (TrIPE).
14 * TrIPE is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * TrIPE is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with TrIPE; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
36 /*----- Header files ------------------------------------------------------*/
52 #include <sys/types.h>
58 #include <sys/socket.h>
60 #include <netinet/in.h>
61 #include <arpa/inet.h>
67 #include <mLib/alloc.h>
68 #include <mLib/arena.h>
69 #include <mLib/base64.h>
70 #include <mLib/bres.h>
71 #include <mLib/daemonize.h>
72 #include <mLib/dstr.h>
74 #include <mLib/fdflags.h>
75 #include <mLib/fwatch.h>
76 #include <mLib/mdwopt.h>
77 #include <mLib/quis.h>
78 #include <mLib/report.h>
80 #include <mLib/selbuf.h>
84 #include <mLib/trace.h>
86 #include <mLib/versioncmp.h>
88 #include <catacomb/buf.h>
90 #include <catacomb/gcipher.h>
91 #include <catacomb/gmac.h>
92 #include <catacomb/grand.h>
93 #include <catacomb/key.h>
94 #include <catacomb/paranoia.h>
96 #include <catacomb/noise.h>
97 #include <catacomb/rand.h>
99 #include <catacomb/mp.h>
100 #include <catacomb/mprand.h>
101 #include <catacomb/dh.h>
102 #include <catacomb/ec.h>
103 #include <catacomb/ec-keys.h>
104 #include <catacomb/group.h>
106 #include "protocol.h"
111 /*----- Magic numbers -----------------------------------------------------*/
113 /* --- Trace flags --- */
121 #define T_KEYEXCH 64u
122 #define T_KEYMGMT 128u
129 #define SEC(n) (n##u)
130 #define MIN(n) (n##u * 60u)
131 #define MEG(n) (n##ul * 1024ul * 1024ul)
133 /* --- Other things --- */
135 #define PKBUFSZ 65536
137 /*----- Cipher selections -------------------------------------------------*/
139 typedef struct algswitch {
140 const gccipher *c; /* Symmetric encryption scheme */
141 const gccipher *mgf; /* Mask-generation function */
142 const gchash *h; /* Hash function */
143 const gcmac *m; /* Message authentication code */
144 size_t hashsz; /* Hash output size */
145 size_t tagsz; /* Length to truncate MAC tags */
146 size_t cksz, mksz; /* Key lengths for @c@ and @m@ */
149 extern algswitch algs;
151 #define MAXHASHSZ 64 /* Largest possible hash size */
153 #define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
155 /*----- Data structures ---------------------------------------------------*/
157 /* --- Socket addresses --- *
159 * A magic union of supported socket addresses.
164 struct sockaddr_in sin;
167 /* --- Sequence number checking --- */
169 typedef struct seqwin {
170 uint32 seq; /* First acceptable input sequence */
171 uint32 win; /* Window of acceptable numbers */
174 #define SEQ_WINSZ 32 /* Bits in sequence number window */
176 /* --- A symmetric keyset --- *
178 * A keyset contains a set of symmetric keys for encrypting and decrypting
179 * packets. Keysets are stored in a list, sorted in reverse order of
180 * creation, so that the most recent keyset (the one most likely to be used)
183 * Each keyset has a time limit and a data limit. The keyset is destroyed
184 * when either it has existed for too long, or it has been used to encrypt
185 * too much data. New key exchanges are triggered when keys are close to
189 typedef struct keyset {
190 struct keyset *next; /* Next active keyset in the list */
191 unsigned ref; /* Reference count for keyset */
192 struct peer *p; /* Pointer to peer structure */
193 time_t t_exp; /* Expiry time for this keyset */
194 unsigned long sz_exp; /* Data limit for the keyset */
195 T( unsigned seq; ) /* Sequence number for tracing */
196 unsigned f; /* Various useful flags */
197 gcipher *cin, *cout; /* Keyset ciphers for encryption */
198 size_t tagsz; /* Length to truncate MAC tags */
199 gmac *min, *mout; /* Keyset MACs for integrity */
200 uint32 oseq; /* Outbound sequence number */
201 seqwin iseq; /* Inbound sequence number */
204 #define KSF_LISTEN 1u /* Don't encrypt packets yet */
205 #define KSF_LINK 2u /* Key is in a linked list */
207 /* --- Key exchange --- *
209 * TrIPE uses the Wrestlers Protocol for its key exchange. The Wrestlers
210 * Protocol has a number of desirable features (e.g., perfect forward
211 * secrecy, and zero-knowledge authentication) which make it attractive for
212 * use in TrIPE. The Wrestlers Protocol was designed by Mark Wooding and
218 typedef struct kxchal {
219 struct keyexch *kx; /* Pointer back to key exchange */
220 ge *c; /* Responder's challenge */
221 ge *r; /* My reply to the challenge */
222 keyset *ks; /* Pointer to temporary keyset */
223 unsigned f; /* Various useful flags */
224 sel_timer t; /* Response timer for challenge */
225 octet hc[MAXHASHSZ]; /* Hash of his challenge */
226 octet ck[MAXHASHSZ]; /* His magical check value */
227 octet hswrq_in[MAXHASHSZ]; /* Inbound switch request message */
228 octet hswok_in[MAXHASHSZ]; /* Inbound switch confirmation */
229 octet hswrq_out[MAXHASHSZ]; /* Outbound switch request message */
230 octet hswok_out[MAXHASHSZ]; /* Outbound switch confirmation */
233 typedef struct keyexch {
234 struct peer *p; /* Pointer back to the peer */
235 keyset **ks; /* Peer's list of keysets */
236 unsigned f; /* Various useful flags */
237 unsigned s; /* Current state in exchange */
238 sel_timer t; /* Timer for next exchange */
239 ge *kpub; /* Peer's public key */
240 time_t texp_kpub; /* Expiry time for public key */
241 mp *alpha; /* My temporary secret */
242 ge *c; /* My challenge */
243 ge *rx; /* The expected response */
244 unsigned nr; /* Number of extant responses */
245 time_t t_valid; /* When this exchange goes bad */
246 octet hc[MAXHASHSZ]; /* Hash of my challenge */
247 kxchal *r[KX_NCHAL]; /* Array of challenges */
250 #define KXF_TIMER 1u /* Waiting for a timer to go off */
251 #define KXF_DEAD 2u /* The key-exchanger isn't up */
252 #define KXF_PUBKEY 4u /* Key exchanger has a public key */
255 KXS_DEAD, /* Uninitialized state (magical) */
256 KXS_CHAL, /* Main answer-challenges state */
257 KXS_COMMIT, /* Committed: send switch request */
258 KXS_SWITCH /* Switched: send confirmation */
261 /* --- Tunnel structure --- *
263 * Used to maintain system-specific information about the tunnel interface.
266 typedef struct tunnel tunnel;
269 typedef struct tunnel_ops {
270 const char *name; /* Name of this tunnel driver */
271 void (*init)(void); /* Initializes the system */
272 tunnel *(*create)(struct peer */*p*/); /* Initializes a new tunnel */
273 const char *(*ifname)(tunnel */*t*/); /* Returns tunnel's interface name */
274 void (*inject)(tunnel */*t*/, buf */*b*/); /* Sends packet through if */
275 void (*destroy)(tunnel */*t*/); /* Destroys a tunnel */
278 #ifndef TUN_INTERNALS
279 struct tunnel { const tunnel_ops *ops; };
282 /* --- Peer statistics --- *
284 * Contains various interesting and not-so-interesting statistics about a
285 * peer. This is updated by various parts of the code. The format of the
286 * structure isn't considered private, and @p_stats@ returns a pointer to the
287 * statistics block for a given peer.
290 typedef struct stats {
291 unsigned long sz_in, sz_out; /* Size of all data in and out */
292 unsigned long sz_kxin, sz_kxout; /* Size of key exchange messages */
293 unsigned long sz_ipin, sz_ipout; /* Size of encapsulated IP packets */
294 time_t t_start, t_last, t_kx; /* Time peer created, last pk, kx */
295 unsigned long n_reject; /* Number of rejected packets */
296 unsigned long n_in, n_out; /* Number of packets in and out */
297 unsigned long n_kxin, n_kxout; /* Number of key exchange packets */
298 unsigned long n_ipin, n_ipout; /* Number of encrypted packets */
301 /* --- Peer structure --- *
303 * The main structure which glues everything else together.
306 typedef struct peerspec {
307 char *name; /* Peer's name */
308 const tunnel_ops *tops; /* Tunnel operations */
309 unsigned long t_ka; /* Keep alive interval */
310 addr sa; /* Socket address to speak to */
311 size_t sasz; /* Socket address size */
314 typedef struct peer {
315 struct peer *next, *prev; /* Links to next and previous */
316 struct ping *pings; /* Pings we're waiting for */
317 peerspec spec; /* Specifications for this peer */
318 tunnel *t; /* Tunnel for local packets */
319 char *ifname; /* Interface name for tunnel */
320 keyset *ks; /* List head for keysets */
321 buf b; /* Buffer for sending packets */
322 stats st; /* Statistics */
323 keyexch kx; /* Key exchange protocol block */
324 sel_timer tka; /* Timer for keepalives */
327 typedef struct ping {
328 struct ping *next, *prev; /* Links to next and previous */
329 peer *p; /* Peer so we can free it */
330 unsigned msg; /* Kind of response expected */
331 uint32 id; /* Id so we can recognize response */
332 octet magic[32]; /* Some random data */
333 sel_timer t; /* Timeout for ping */
334 void (*func)(int /*rc*/, void */*arg*/); /* Function to call when done */
335 void *arg; /* Argument for callback */
346 /* --- Admin structure --- */
348 #define OBUFSZ 16384u
350 typedef struct obuf {
351 struct obuf *next; /* Next buffer in list */
352 char *p_in, *p_out; /* Pointers into the buffer */
353 char buf[OBUFSZ]; /* The actual buffer */
356 typedef struct oqueue {
357 obuf *hd, *tl; /* Head and tail pointers */
362 typedef struct admin_bgop {
363 struct admin_bgop *next, *prev; /* Links to next and previous */
364 struct admin *a; /* Owner job */
365 char *tag; /* Tag string for messages */
366 void (*cancel)(struct admin_bgop *); /* Destructor function */
369 typedef struct admin_resop {
370 admin_bgop bg; /* Background operation header */
371 char *addr; /* Hostname to be resolved */
372 bres_client r; /* Background resolver task */
373 sel_timer t; /* Timer for resolver */
374 addr sa; /* Socket address */
375 size_t sasz; /* Socket address size */
376 void (*func)(struct admin_resop *, int); /* Handler */
379 enum { ARES_OK, ARES_FAIL };
381 typedef struct admin_addop {
382 admin_resop r; /* Name resolution header */
383 peerspec peer; /* Peer pending creation */
386 typedef struct admin_greetop {
387 admin_resop r; /* Name resolution header */
388 void *c; /* Challenge block */
389 size_t sz; /* Length of challenge */
392 typedef struct admin_pingop {
393 admin_bgop bg; /* Background operation header */
394 ping ping; /* Ping pending response */
395 struct timeval pingtime; /* Time last ping was sent */
398 typedef struct admin_service {
399 sym_base _b; /* Hash table base structure */
400 char *version; /* The provided version */
401 struct admin *prov; /* Which client provides me */
402 struct admin_service *next, *prev; /* Client's list of services */
405 typedef struct admin_svcop {
406 admin_bgop bg; /* Background operation header */
407 struct admin *prov; /* Client servicing this job */
408 unsigned short index; /* This job's index */
409 struct admin_svcop *next, *prev; /* Links for provider's jobs */
412 typedef struct admin_jobentry {
413 unsigned short seq; /* Zero if unused */
415 admin_svcop *op; /* Operation, if slot in use, ... */
416 uint32 next; /* ... or index of next free slot */
420 typedef struct admin_jobtable {
421 uint32 n, sz; /* Used slots and table size */
422 admin_svcop *active; /* List of active jobs */
423 uint32 free; /* Index of first free slot */
424 admin_jobentry *v; /* And the big array of entries */
427 typedef struct admin {
428 struct admin *next, *prev; /* Links to next and previous */
429 unsigned f; /* Various useful flags */
430 unsigned ref; /* Reference counter */
432 unsigned seq; /* Sequence number for tracing */
434 oqueue out; /* Output buffer list */
435 oqueue delay; /* Delayed output buffer list */
436 admin_bgop *bg; /* Backgrounded operations */
437 admin_service *svcs; /* Which services I provide */
438 admin_jobtable j; /* Table of outstanding jobs */
439 selbuf b; /* Line buffer for commands */
440 sel_file w; /* Selector for write buffering */
443 #define AF_DEAD 1u /* Destroy this admin block */
444 #define AF_CLOSE 2u /* Client closed connection */
445 #define AF_NOTE 4u /* Catch notifications */
446 #define AF_WARN 8u /* Catch warning messages */
448 #define AF_TRACE 16u /* Catch tracing */
452 # define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN)
454 # define AF_ALLMSGS (AF_NOTE | AF_WARN)
457 /*----- Global variables --------------------------------------------------*/
459 extern sel_state sel; /* Global I/O event state */
460 extern group *gg; /* The group we work in */
461 extern size_t indexsz; /* Size of exponent for the group */
462 extern mp *kpriv; /* Our private key */
463 extern ge *kpub; /* Our public key */
464 extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ];
465 extern const tunnel_ops *tunnels[]; /* Table of tunnels (0-term) */
466 extern const tunnel_ops *tun_default; /* Default tunnel to use */
469 extern const trace_opt tr_opts[]; /* Trace options array */
470 extern unsigned tr_flags; /* Trace options flags */
473 /*----- Other macros ------------------------------------------------------*/
475 #define TIMER noise_timer(RAND_GLOBAL)
477 /*----- Key management ----------------------------------------------------*/
479 /* --- @km_reload@ --- *
483 * Returns: Zero if OK, nonzero to force reloading of keys.
485 * Use: Checks the keyrings to see if they need reloading.
488 extern int km_reload(void);
490 /* --- @km_init@ --- *
492 * Arguments: @const char *kr_priv@ = private keyring file
493 * @const char *kr_pub@ = public keyring file
494 * @const char *tag@ = tag to load
498 * Use: Initializes, and loads the private key.
501 extern void km_init(const char */*kr_priv*/, const char */*kr_pub*/,
502 const char */*tag*/);
504 /* --- @km_getpubkey@ --- *
506 * Arguments: @const char *tag@ = public key tag to load
507 * @ge *kpub@ = where to put the public key
508 * @time_t *t_exp@ = where to put the expiry time
510 * Returns: Zero if OK, nonzero if it failed.
512 * Use: Fetches a public key from the keyring.
515 extern int km_getpubkey(const char */*tag*/, ge */*kpub*/,
518 /*----- Key exchange ------------------------------------------------------*/
520 /* --- @kx_start@ --- *
522 * Arguments: @keyexch *kx@ = pointer to key exchange context
523 * @int forcep@ = nonzero to ignore the quiet timer
527 * Use: Stimulates a key exchange. If a key exchage is in progress,
528 * a new challenge is sent (unless the quiet timer forbids
529 * this); if no exchange is in progress, one is commenced.
532 extern void kx_start(keyexch */*kx*/, int /*forcep*/);
534 /* --- @kx_message@ --- *
536 * Arguments: @keyexch *kx@ = pointer to key exchange context
537 * @unsigned msg@ = the message code
538 * @buf *b@ = pointer to buffer containing the packet
542 * Use: Reads a packet containing key exchange messages and handles
546 extern void kx_message(keyexch */*kx*/, unsigned /*msg*/, buf */*b*/);
548 /* --- @kx_free@ --- *
550 * Arguments: @keyexch *kx@ = pointer to key exchange context
554 * Use: Frees everything in a key exchange context.
557 extern void kx_free(keyexch */*kx*/);
559 /* --- @kx_newkeys@ --- *
561 * Arguments: @keyexch *kx@ = pointer to key exchange context
565 * Use: Informs the key exchange module that its keys may have
566 * changed. If fetching the new keys fails, the peer will be
567 * destroyed, we log messages and struggle along with the old
571 extern void kx_newkeys(keyexch */*kx*/);
573 /* --- @kx_init@ --- *
575 * Arguments: @keyexch *kx@ = pointer to key exchange context
576 * @peer *p@ = pointer to peer context
577 * @keyset **ks@ = pointer to keyset list
579 * Returns: Zero if OK, nonzero if it failed.
581 * Use: Initializes a key exchange module. The module currently
582 * contains no keys, and will attempt to initiate a key
586 extern int kx_init(keyexch */*kx*/, peer */*p*/, keyset **/*ks*/);
588 /*----- Keysets and symmetric cryptography --------------------------------*/
590 /* --- @ks_drop@ --- *
592 * Arguments: @keyset *ks@ = pointer to a keyset
596 * Use: Decrements a keyset's reference counter. If the counter hits
597 * zero, the keyset is freed.
600 extern void ks_drop(keyset */*ks*/);
602 /* --- @ks_gen@ --- *
604 * Arguments: @const void *k@ = pointer to key material
605 * @size_t x, y, z@ = offsets into key material (see below)
606 * @peer *p@ = pointer to peer information
608 * Returns: A pointer to the new keyset.
610 * Use: Derives a new keyset from the given key material. The
611 * offsets @x@, @y@ and @z@ separate the key material into three
612 * parts. Between the @k@ and @k + x@ is `my' contribution to
613 * the key material; between @k + x@ and @k + y@ is `your'
614 * contribution; and between @k + y@ and @k + z@ is a shared
615 * value we made together. These are used to construct two
616 * pairs of symmetric keys. Each pair consists of an encryption
617 * key and a message authentication key. One pair is used for
618 * outgoing messages, the other for incoming messages.
620 * The new key is marked so that it won't be selected for output
621 * by @ksl_encrypt@. You can still encrypt data with it by
622 * calling @ks_encrypt@ directly.
625 extern keyset *ks_gen(const void */*k*/,
626 size_t /*x*/, size_t /*y*/, size_t /*z*/,
629 /* --- @ks_tregen@ --- *
631 * Arguments: @keyset *ks@ = pointer to a keyset
633 * Returns: The time at which moves ought to be made to replace this key.
636 extern time_t ks_tregen(keyset */*ks*/);
638 /* --- @ks_activate@ --- *
640 * Arguments: @keyset *ks@ = pointer to a keyset
644 * Use: Activates a keyset, so that it can be used for encrypting
648 extern void ks_activate(keyset */*ks*/);
650 /* --- @ks_encrypt@ --- *
652 * Arguments: @keyset *ks@ = pointer to a keyset
653 * @unsigned ty@ = message type
654 * @buf *b@ = pointer to input buffer
655 * @buf *bb@ = pointer to output buffer
657 * Returns: Zero if OK, nonzero if the key needs replacing. If the
658 * encryption failed, the output buffer is broken and zero is
661 * Use: Encrypts a block of data using the key. Note that the `key
662 * ought to be replaced' notification is only ever given once
663 * for each key. Also note that this call forces a keyset to be
664 * used even if it's marked as not for data output.
667 extern int ks_encrypt(keyset */*ks*/, unsigned /*ty*/,
668 buf */*b*/, buf */*bb*/);
670 /* --- @ks_decrypt@ --- *
672 * Arguments: @keyset *ks@ = pointer to a keyset
673 * @unsigned ty@ = expected type code
674 * @buf *b@ = pointer to an input buffer
675 * @buf *bb@ = pointer to an output buffer
677 * Returns: Zero on success, or nonzero if there was some problem.
679 * Use: Attempts to decrypt a message using a given key. Note that
680 * requesting decryption with a key directly won't clear a
681 * marking that it's not for encryption.
684 extern int ks_decrypt(keyset */*ks*/, unsigned /*ty*/,
685 buf */*b*/, buf */*bb*/);
687 /* --- @ksl_free@ --- *
689 * Arguments: @keyset **ksroot@ = pointer to keyset list head
693 * Use: Frees (releases references to) all of the keys in a keyset.
696 extern void ksl_free(keyset **/*ksroot*/);
698 /* --- @ksl_link@ --- *
700 * Arguments: @keyset **ksroot@ = pointer to keyset list head
701 * @keyset *ks@ = pointer to a keyset
705 * Use: Links a keyset into a list. A keyset can only be on one list
706 * at a time. Bad things happen otherwise.
709 extern void ksl_link(keyset **/*ksroot*/, keyset */*ks*/);
711 /* --- @ksl_prune@ --- *
713 * Arguments: @keyset **ksroot@ = pointer to keyset list head
717 * Use: Prunes the keyset list by removing keys which mustn't be used
721 extern void ksl_prune(keyset **/*ksroot*/);
723 /* --- @ksl_encrypt@ --- *
725 * Arguments: @keyset **ksroot@ = pointer to keyset list head
726 * @unsigned ty@ = message type
727 * @buf *b@ = pointer to input buffer
728 * @buf *bb@ = pointer to output buffer
730 * Returns: Nonzero if a new key is needed.
732 * Use: Encrypts a packet.
735 extern int ksl_encrypt(keyset **/*ksroot*/, unsigned /*ty*/,
736 buf */*b*/, buf */*bb*/);
738 /* --- @ksl_decrypt@ --- *
740 * Arguments: @keyset **ksroot@ = pointer to keyset list head
741 * @unsigned ty@ = expected type code
742 * @buf *b@ = pointer to input buffer
743 * @buf *bb@ = pointer to output buffer
745 * Returns: Nonzero if the packet couldn't be decrypted.
747 * Use: Decrypts a packet.
750 extern int ksl_decrypt(keyset **/*ksroot*/, unsigned /*ty*/,
751 buf */*b*/, buf */*bb*/);
753 /*----- Challenges --------------------------------------------------------*/
757 * Arguments: @buf *b@ = where to put the challenge
759 * Returns: Zero if OK, nonzero on error.
761 * Use: Issues a new challenge.
764 extern int c_new(buf */*b*/);
766 /* --- @c_check@ --- *
768 * Arguments: @buf *b@ = where to find the challenge
770 * Returns: Zero if OK, nonzero if it didn't work.
772 * Use: Checks a challenge. On failure, the buffer is broken.
775 extern int c_check(buf */*b*/);
777 /*----- Administration interface ------------------------------------------*/
779 #define A_END ((char *)0)
781 /* --- @a_warn@ --- *
783 * Arguments: @const char *fmt@ = pointer to format string
784 * @...@ = other arguments
788 * Use: Informs all admin connections of a warning.
791 extern void a_warn(const char */*fmt*/, ...);
793 /* --- @a_notify@ --- *
795 * Arguments: @const char *fmt@ = pointer to format string
796 * @...@ = other arguments
800 * Use: Sends a notification to interested admin connections.
803 extern void a_notify(const char */*fmt*/, ...);
805 /* --- @a_create@ --- *
807 * Arguments: @int fd_in, fd_out@ = file descriptors to use
808 * @unsigned f@ = initial flags to set
812 * Use: Creates a new admin connection.
815 extern void a_create(int /*fd_in*/, int /*fd_out*/, unsigned /*f*/);
817 /* --- @a_quit@ --- *
823 * Use: Shuts things down nicely.
826 extern void a_quit(void);
828 /* --- @a_preselect@ --- *
834 * Use: Informs the admin module that we're about to select again,
835 * and that it should do cleanup things it has delayed until a
839 extern void a_preselect(void);
841 /* --- @a_daemon@ --- *
847 * Use: Informs the admin module that it's a daemon.
850 extern void a_daemon(void);
852 /* --- @a_init@ --- *
854 * Arguments: @const char *sock@ = socket name to create
858 * Use: Creates the admin listening socket.
861 extern void a_init(const char */*sock*/);
863 /*----- Peer management ---------------------------------------------------*/
865 /* --- @p_txstart@ --- *
867 * Arguments: @peer *p@ = pointer to peer block
868 * @unsigned msg@ = message type code
870 * Returns: A pointer to a buffer to write to.
872 * Use: Starts sending to a peer. Only one send can happen at a
876 extern buf *p_txstart(peer */*p*/, unsigned /*msg*/);
878 /* --- @p_txend@ --- *
880 * Arguments: @peer *p@ = pointer to peer block
884 * Use: Sends a packet to the peer.
887 extern void p_txend(peer */*p*/);
889 /* --- @p_pingsend@ --- *
891 * Arguments: @peer *p@ = destination peer
892 * @ping *pg@ = structure to fill in
893 * @unsigned type@ = message type
894 * @unsigned long timeout@ = how long to wait before giving up
895 * @void (*func)(int, void *)@ = callback function
896 * @void *arg@ = argument for callback
898 * Returns: Zero if successful, nonzero if it failed.
900 * Use: Sends a ping to a peer. Call @func@ with a nonzero argument
901 * if we get an answer within the timeout, or zero if no answer.
904 extern int p_pingsend(peer */*p*/, ping */*pg*/, unsigned /*type*/,
905 unsigned long /*timeout*/,
906 void (*/*func*/)(int, void *), void */*arg*/);
908 /* --- @p_pingdone@ --- *
910 * Arguments: @ping *p@ = ping structure
911 * @int rc@ = return code to pass on
915 * Use: Disposes of a ping structure, maybe sending a notification.
918 extern void p_pingdone(ping */*p*/, int /*rc*/);
920 /* --- @p_greet@ --- *
922 * Arguments: @peer *p@ = peer to send to
923 * @const void *c@ = pointer to challenge
924 * @size_t sz@ = size of challenge
928 * Use: Sends a greeting packet.
931 extern void p_greet(peer */*p*/, const void */*c*/, size_t /*sz*/);
935 * Arguments: @peer *p@ = pointer to peer block
936 * @buf *b@ = buffer containing incoming packet
940 * Use: Handles a packet which needs to be sent to a peer.
943 extern void p_tun(peer */*p*/, buf */*b*/);
945 /* --- @p_keyreload@ --- *
951 * Use: Forces a check of the daemon's keyring files.
954 extern void p_keyreload(void);
956 /* --- @p_interval@ --- *
962 * Use: Called periodically to do tidying.
965 extern void p_interval(void);
967 /* --- @p_stats@ --- *
969 * Arguments: @peer *p@ = pointer to a peer block
971 * Returns: A pointer to the peer's statistics.
974 extern stats *p_stats(peer */*p*/);
976 /* --- @p_ifname@ --- *
978 * Arguments: @peer *p@ = pointer to a peer block
980 * Returns: A pointer to the peer's interface name.
983 extern const char *p_ifname(peer */*p*/);
985 /* --- @p_setifname@ --- *
987 * Arguments: @peer *p@ = pointer to a peer block
988 * @const char *name@ = pointer to the new name
992 * Use: Changes the name held for a peer's interface.
995 extern void p_setifname(peer */*p*/, const char */*name*/);
997 /* --- @p_addr@ --- *
999 * Arguments: @peer *p@ = pointer to a peer block
1001 * Returns: A pointer to the peer's address.
1004 extern const addr *p_addr(peer */*p*/);
1006 /* --- @p_init@ --- *
1008 * Arguments: @struct in_addr addr@ = address to bind to
1009 * @unsigned port@ = port number to listen to
1013 * Use: Initializes the peer system; creates the socket.
1016 extern void p_init(struct in_addr /*addr*/, unsigned /*port*/);
1018 /* --- @p_port@ --- *
1022 * Returns: Port number used for socket.
1025 unsigned p_port(void);
1027 /* --- @p_create@ --- *
1029 * Arguments: @peerspec *spec@ = information about this peer
1031 * Returns: Pointer to the peer block, or null if it failed.
1033 * Use: Creates a new named peer block. No peer is actually attached
1037 extern peer *p_create(peerspec */*spec*/);
1039 /* --- @p_name@ --- *
1041 * Arguments: @peer *p@ = pointer to a peer block
1043 * Returns: A pointer to the peer's name.
1045 * Use: Equivalent to @p_spec(p)->name@.
1048 extern const char *p_name(peer */*p*/);
1050 /* --- @p_spec@ --- *
1052 * Arguments: @peer *p@ = pointer to a peer block
1054 * Returns: Pointer to the peer's specification
1057 extern const peerspec *p_spec(peer */*p*/);
1059 /* --- @p_find@ --- *
1061 * Arguments: @const char *name@ = name to look up
1063 * Returns: Pointer to the peer block, or null if not found.
1065 * Use: Finds a peer by name.
1068 extern peer *p_find(const char */*name*/);
1070 /* --- @p_destroy@ --- *
1072 * Arguments: @peer *p@ = pointer to a peer
1076 * Use: Destroys a peer.
1079 extern void p_destroy(peer */*p*/);
1081 /* --- @p_first@, @p_next@ --- *
1083 * Arguments: @peer *p@ = a peer block
1085 * Returns: @peer_first@ returns the first peer in some ordering;
1086 * @peer_next@ returns the peer following a given one in the
1087 * same ordering. Null is returned for the end of the list.
1090 extern peer *p_first(void);
1091 extern peer *p_next(peer */*p*/);
1093 /*----- Tunnel drivers ----------------------------------------------------*/
1096 extern const tunnel_ops tun_linux;
1100 extern const tunnel_ops tun_unet;
1104 extern const tunnel_ops tun_bsd;
1107 extern const tunnel_ops tun_slip;
1109 /*----- Other handy utilities ---------------------------------------------*/
1111 /* --- @mpstr@ --- *
1113 * Arguments: @mp *m@ = a multiprecision integer
1115 * Returns: A pointer to the integer's textual representation.
1117 * Use: Converts a multiprecision integer to a string. Corrupts
1121 extern const char *mpstr(mp */*m*/);
1123 /* --- @gestr@ --- *
1125 * Arguments: @group *g@ = a group
1126 * @ge *x@ = a group element
1128 * Returns: A pointer to the element's textual representation.
1130 * Use: Converts a group element to a string. Corrupts
1134 extern const char *gestr(group */*g*/, ge */*x*/);
1136 /* --- @timestr@ --- *
1138 * Arguments: @time_t t@ = a time to convert
1140 * Returns: A pointer to a textual representation of the time.
1142 * Use: Converts a time to a textual representation. Corrupts
1146 extern const char *timestr(time_t /*t*/);
1148 /* --- @mystrieq@ --- *
1150 * Arguments: @const char *x, *y@ = two strings
1152 * Returns: True if @x@ and @y are equal, up to case.
1155 extern int mystrieq(const char */*x*/, const char */*y*/);
1157 /* --- @seq_reset@ --- *
1159 * Arguments: @seqwin *s@ = sequence-checking window
1163 * Use: Resets a sequence number window.
1166 extern void seq_reset(seqwin */*s*/);
1168 /* --- @seq_check@ --- *
1170 * Arguments: @seqwin *s@ = sequence-checking window
1171 * @uint32 q@ = sequence number to check
1172 * @const char *service@ = service to report message from
1174 * Returns: A @SEQ_@ code.
1176 * Use: Checks a sequence number against the window, updating things
1180 extern int seq_check(seqwin */*s*/, uint32 /*q*/, const char */*service*/);
1182 /*----- That's all, folks -------------------------------------------------*/