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/macros.h>
77 #include <mLib/mdwopt.h>
78 #include <mLib/quis.h>
79 #include <mLib/report.h>
81 #include <mLib/selbuf.h>
85 #include <mLib/trace.h>
87 #include <mLib/versioncmp.h>
89 #include <catacomb/buf.h>
91 #include <catacomb/gcipher.h>
92 #include <catacomb/gmac.h>
93 #include <catacomb/grand.h>
94 #include <catacomb/key.h>
95 #include <catacomb/paranoia.h>
97 #include <catacomb/noise.h>
98 #include <catacomb/rand.h>
100 #include <catacomb/mp.h>
101 #include <catacomb/mprand.h>
102 #include <catacomb/dh.h>
103 #include <catacomb/ec.h>
104 #include <catacomb/ec-keys.h>
105 #include <catacomb/group.h>
107 #include "protocol.h"
112 /*----- Magic numbers -----------------------------------------------------*/
114 /* --- Trace flags --- */
122 #define T_KEYEXCH 64u
123 #define T_KEYMGMT 128u
130 #define SEC(n) (n##u)
131 #define MIN(n) (n##u * 60u)
132 #define MEG(n) (n##ul * 1024ul * 1024ul)
134 /* --- Other things --- */
136 #define PKBUFSZ 65536
138 /*----- Cipher selections -------------------------------------------------*/
140 typedef struct algswitch {
141 const gccipher *c; /* Symmetric encryption scheme */
142 const gccipher *mgf; /* Mask-generation function */
143 const gchash *h; /* Hash function */
144 const gcmac *m; /* Message authentication code */
145 size_t hashsz; /* Hash output size */
146 size_t tagsz; /* Length to truncate MAC tags */
147 size_t cksz, mksz; /* Key lengths for @c@ and @m@ */
150 extern algswitch algs;
152 #define MAXHASHSZ 64 /* Largest possible hash size */
154 #define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
156 /*----- Data structures ---------------------------------------------------*/
158 /* --- Socket addresses --- *
160 * A magic union of supported socket addresses.
165 struct sockaddr_in sin;
168 /* --- Sequence number checking --- */
170 typedef struct seqwin {
171 uint32 seq; /* First acceptable input sequence */
172 uint32 win; /* Window of acceptable numbers */
175 #define SEQ_WINSZ 32 /* Bits in sequence number window */
177 /* --- A symmetric keyset --- *
179 * A keyset contains a set of symmetric keys for encrypting and decrypting
180 * packets. Keysets are stored in a list, sorted in reverse order of
181 * creation, so that the most recent keyset (the one most likely to be used)
184 * Each keyset has a time limit and a data limit. The keyset is destroyed
185 * when either it has existed for too long, or it has been used to encrypt
186 * too much data. New key exchanges are triggered when keys are close to
190 typedef struct keyset {
191 struct keyset *next; /* Next active keyset in the list */
192 unsigned ref; /* Reference count for keyset */
193 struct peer *p; /* Pointer to peer structure */
194 time_t t_exp; /* Expiry time for this keyset */
195 unsigned long sz_exp; /* Data limit for the keyset */
196 T( unsigned seq; ) /* Sequence number for tracing */
197 unsigned f; /* Various useful flags */
198 gcipher *cin, *cout; /* Keyset ciphers for encryption */
199 size_t tagsz; /* Length to truncate MAC tags */
200 gmac *min, *mout; /* Keyset MACs for integrity */
201 uint32 oseq; /* Outbound sequence number */
202 seqwin iseq; /* Inbound sequence number */
205 #define KSF_LISTEN 1u /* Don't encrypt packets yet */
206 #define KSF_LINK 2u /* Key is in a linked list */
208 /* --- Key exchange --- *
210 * TrIPE uses the Wrestlers Protocol for its key exchange. The Wrestlers
211 * Protocol has a number of desirable features (e.g., perfect forward
212 * secrecy, and zero-knowledge authentication) which make it attractive for
213 * use in TrIPE. The Wrestlers Protocol was designed by Mark Wooding and
219 typedef struct kxchal {
220 struct keyexch *kx; /* Pointer back to key exchange */
221 ge *c; /* Responder's challenge */
222 ge *r; /* My reply to the challenge */
223 keyset *ks; /* Pointer to temporary keyset */
224 unsigned f; /* Various useful flags */
225 sel_timer t; /* Response timer for challenge */
226 octet hc[MAXHASHSZ]; /* Hash of his challenge */
227 octet ck[MAXHASHSZ]; /* His magical check value */
228 octet hswrq_in[MAXHASHSZ]; /* Inbound switch request message */
229 octet hswok_in[MAXHASHSZ]; /* Inbound switch confirmation */
230 octet hswrq_out[MAXHASHSZ]; /* Outbound switch request message */
231 octet hswok_out[MAXHASHSZ]; /* Outbound switch confirmation */
234 typedef struct keyexch {
235 struct peer *p; /* Pointer back to the peer */
236 keyset **ks; /* Peer's list of keysets */
237 unsigned f; /* Various useful flags */
238 unsigned s; /* Current state in exchange */
239 sel_timer t; /* Timer for next exchange */
240 ge *kpub; /* Peer's public key */
241 time_t texp_kpub; /* Expiry time for public key */
242 mp *alpha; /* My temporary secret */
243 ge *c; /* My challenge */
244 ge *rx; /* The expected response */
245 unsigned nr; /* Number of extant responses */
246 time_t t_valid; /* When this exchange goes bad */
247 octet hc[MAXHASHSZ]; /* Hash of my challenge */
248 kxchal *r[KX_NCHAL]; /* Array of challenges */
251 #define KXF_TIMER 1u /* Waiting for a timer to go off */
252 #define KXF_DEAD 2u /* The key-exchanger isn't up */
253 #define KXF_PUBKEY 4u /* Key exchanger has a public key */
256 KXS_DEAD, /* Uninitialized state (magical) */
257 KXS_CHAL, /* Main answer-challenges state */
258 KXS_COMMIT, /* Committed: send switch request */
259 KXS_SWITCH /* Switched: send confirmation */
262 /* --- Tunnel structure --- *
264 * Used to maintain system-specific information about the tunnel interface.
267 typedef struct tunnel tunnel;
270 typedef struct tunnel_ops {
271 const char *name; /* Name of this tunnel driver */
272 void (*init)(void); /* Initializes the system */
273 tunnel *(*create)(struct peer */*p*/, char **/*ifn*/);
274 /* Initializes a new tunnel */
275 void (*setifname)(tunnel */*t*/, const char */*ifn*/);
276 /* Notifies ifname change */
277 void (*inject)(tunnel */*t*/, buf */*b*/); /* Sends packet through if */
278 void (*destroy)(tunnel */*t*/); /* Destroys a tunnel */
281 #ifndef TUN_INTERNALS
282 struct tunnel { const tunnel_ops *ops; };
285 /* --- Peer statistics --- *
287 * Contains various interesting and not-so-interesting statistics about a
288 * peer. This is updated by various parts of the code. The format of the
289 * structure isn't considered private, and @p_stats@ returns a pointer to the
290 * statistics block for a given peer.
293 typedef struct stats {
294 unsigned long sz_in, sz_out; /* Size of all data in and out */
295 unsigned long sz_kxin, sz_kxout; /* Size of key exchange messages */
296 unsigned long sz_ipin, sz_ipout; /* Size of encapsulated IP packets */
297 time_t t_start, t_last, t_kx; /* Time peer created, last pk, kx */
298 unsigned long n_reject; /* Number of rejected packets */
299 unsigned long n_in, n_out; /* Number of packets in and out */
300 unsigned long n_kxin, n_kxout; /* Number of key exchange packets */
301 unsigned long n_ipin, n_ipout; /* Number of encrypted packets */
304 /* --- Peer structure --- *
306 * The main structure which glues everything else together.
309 typedef struct peerspec {
310 char *name; /* Peer's name */
311 const tunnel_ops *tops; /* Tunnel operations */
312 unsigned long t_ka; /* Keep alive interval */
313 addr sa; /* Socket address to speak to */
314 size_t sasz; /* Socket address size */
317 typedef struct peer {
318 struct peer *next, *prev; /* Links to next and previous */
319 struct ping *pings; /* Pings we're waiting for */
320 peerspec spec; /* Specifications for this peer */
321 tunnel *t; /* Tunnel for local packets */
322 char *ifname; /* Interface name for tunnel */
323 keyset *ks; /* List head for keysets */
324 buf b; /* Buffer for sending packets */
325 stats st; /* Statistics */
326 keyexch kx; /* Key exchange protocol block */
327 sel_timer tka; /* Timer for keepalives */
330 typedef struct ping {
331 struct ping *next, *prev; /* Links to next and previous */
332 peer *p; /* Peer so we can free it */
333 unsigned msg; /* Kind of response expected */
334 uint32 id; /* Id so we can recognize response */
335 octet magic[32]; /* Some random data */
336 sel_timer t; /* Timeout for ping */
337 void (*func)(int /*rc*/, void */*arg*/); /* Function to call when done */
338 void *arg; /* Argument for callback */
349 /* --- Admin structure --- */
351 #define OBUFSZ 16384u
353 typedef struct obuf {
354 struct obuf *next; /* Next buffer in list */
355 char *p_in, *p_out; /* Pointers into the buffer */
356 char buf[OBUFSZ]; /* The actual buffer */
359 typedef struct oqueue {
360 obuf *hd, *tl; /* Head and tail pointers */
365 typedef struct admin_bgop {
366 struct admin_bgop *next, *prev; /* Links to next and previous */
367 struct admin *a; /* Owner job */
368 char *tag; /* Tag string for messages */
369 void (*cancel)(struct admin_bgop *); /* Destructor function */
372 typedef struct admin_resop {
373 admin_bgop bg; /* Background operation header */
374 char *addr; /* Hostname to be resolved */
375 bres_client r; /* Background resolver task */
376 sel_timer t; /* Timer for resolver */
377 addr sa; /* Socket address */
378 size_t sasz; /* Socket address size */
379 void (*func)(struct admin_resop *, int); /* Handler */
382 enum { ARES_OK, ARES_FAIL };
384 typedef struct admin_addop {
385 admin_resop r; /* Name resolution header */
386 peerspec peer; /* Peer pending creation */
389 typedef struct admin_greetop {
390 admin_resop r; /* Name resolution header */
391 void *c; /* Challenge block */
392 size_t sz; /* Length of challenge */
395 typedef struct admin_pingop {
396 admin_bgop bg; /* Background operation header */
397 ping ping; /* Ping pending response */
398 struct timeval pingtime; /* Time last ping was sent */
401 typedef struct admin_service {
402 sym_base _b; /* Hash table base structure */
403 char *version; /* The provided version */
404 struct admin *prov; /* Which client provides me */
405 struct admin_service *next, *prev; /* Client's list of services */
408 typedef struct admin_svcop {
409 admin_bgop bg; /* Background operation header */
410 struct admin *prov; /* Client servicing this job */
411 unsigned short index; /* This job's index */
412 struct admin_svcop *next, *prev; /* Links for provider's jobs */
415 typedef struct admin_jobentry {
416 unsigned short seq; /* Zero if unused */
418 admin_svcop *op; /* Operation, if slot in use, ... */
419 uint32 next; /* ... or index of next free slot */
423 typedef struct admin_jobtable {
424 uint32 n, sz; /* Used slots and table size */
425 admin_svcop *active; /* List of active jobs */
426 uint32 free; /* Index of first free slot */
427 admin_jobentry *v; /* And the big array of entries */
430 typedef struct admin {
431 struct admin *next, *prev; /* Links to next and previous */
432 unsigned f; /* Various useful flags */
433 unsigned ref; /* Reference counter */
435 unsigned seq; /* Sequence number for tracing */
437 oqueue out; /* Output buffer list */
438 oqueue delay; /* Delayed output buffer list */
439 admin_bgop *bg; /* Backgrounded operations */
440 admin_service *svcs; /* Which services I provide */
441 admin_jobtable j; /* Table of outstanding jobs */
442 selbuf b; /* Line buffer for commands */
443 sel_file w; /* Selector for write buffering */
446 #define AF_DEAD 1u /* Destroy this admin block */
447 #define AF_CLOSE 2u /* Client closed connection */
448 #define AF_NOTE 4u /* Catch notifications */
449 #define AF_WARN 8u /* Catch warning messages */
451 #define AF_TRACE 16u /* Catch tracing */
455 # define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN)
457 # define AF_ALLMSGS (AF_NOTE | AF_WARN)
460 /*----- Global variables --------------------------------------------------*/
462 extern sel_state sel; /* Global I/O event state */
463 extern group *gg; /* The group we work in */
464 extern size_t indexsz; /* Size of exponent for the group */
465 extern mp *kpriv; /* Our private key */
466 extern ge *kpub; /* Our public key */
467 extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ];
468 extern const tunnel_ops *tunnels[]; /* Table of tunnels (0-term) */
469 extern const tunnel_ops *tun_default; /* Default tunnel to use */
472 extern const trace_opt tr_opts[]; /* Trace options array */
473 extern unsigned tr_flags; /* Trace options flags */
476 /*----- Other macros ------------------------------------------------------*/
478 #define TIMER noise_timer(RAND_GLOBAL)
480 /*----- Key management ----------------------------------------------------*/
482 /* --- @km_reload@ --- *
486 * Returns: Zero if OK, nonzero to force reloading of keys.
488 * Use: Checks the keyrings to see if they need reloading.
491 extern int km_reload(void);
493 /* --- @km_init@ --- *
495 * Arguments: @const char *kr_priv@ = private keyring file
496 * @const char *kr_pub@ = public keyring file
497 * @const char *tag@ = tag to load
501 * Use: Initializes, and loads the private key.
504 extern void km_init(const char */*kr_priv*/, const char */*kr_pub*/,
505 const char */*tag*/);
507 /* --- @km_getpubkey@ --- *
509 * Arguments: @const char *tag@ = public key tag to load
510 * @ge *kpub@ = where to put the public key
511 * @time_t *t_exp@ = where to put the expiry time
513 * Returns: Zero if OK, nonzero if it failed.
515 * Use: Fetches a public key from the keyring.
518 extern int km_getpubkey(const char */*tag*/, ge */*kpub*/,
521 /*----- Key exchange ------------------------------------------------------*/
523 /* --- @kx_start@ --- *
525 * Arguments: @keyexch *kx@ = pointer to key exchange context
526 * @int forcep@ = nonzero to ignore the quiet timer
530 * Use: Stimulates a key exchange. If a key exchage is in progress,
531 * a new challenge is sent (unless the quiet timer forbids
532 * this); if no exchange is in progress, one is commenced.
535 extern void kx_start(keyexch */*kx*/, int /*forcep*/);
537 /* --- @kx_message@ --- *
539 * Arguments: @keyexch *kx@ = pointer to key exchange context
540 * @unsigned msg@ = the message code
541 * @buf *b@ = pointer to buffer containing the packet
545 * Use: Reads a packet containing key exchange messages and handles
549 extern void kx_message(keyexch */*kx*/, unsigned /*msg*/, buf */*b*/);
551 /* --- @kx_free@ --- *
553 * Arguments: @keyexch *kx@ = pointer to key exchange context
557 * Use: Frees everything in a key exchange context.
560 extern void kx_free(keyexch */*kx*/);
562 /* --- @kx_newkeys@ --- *
564 * Arguments: @keyexch *kx@ = pointer to key exchange context
568 * Use: Informs the key exchange module that its keys may have
569 * changed. If fetching the new keys fails, the peer will be
570 * destroyed, we log messages and struggle along with the old
574 extern void kx_newkeys(keyexch */*kx*/);
576 /* --- @kx_init@ --- *
578 * Arguments: @keyexch *kx@ = pointer to key exchange context
579 * @peer *p@ = pointer to peer context
580 * @keyset **ks@ = pointer to keyset list
582 * Returns: Zero if OK, nonzero if it failed.
584 * Use: Initializes a key exchange module. The module currently
585 * contains no keys, and will attempt to initiate a key
589 extern int kx_init(keyexch */*kx*/, peer */*p*/, keyset **/*ks*/);
591 /*----- Keysets and symmetric cryptography --------------------------------*/
593 /* --- @ks_drop@ --- *
595 * Arguments: @keyset *ks@ = pointer to a keyset
599 * Use: Decrements a keyset's reference counter. If the counter hits
600 * zero, the keyset is freed.
603 extern void ks_drop(keyset */*ks*/);
605 /* --- @ks_gen@ --- *
607 * Arguments: @const void *k@ = pointer to key material
608 * @size_t x, y, z@ = offsets into key material (see below)
609 * @peer *p@ = pointer to peer information
611 * Returns: A pointer to the new keyset.
613 * Use: Derives a new keyset from the given key material. The
614 * offsets @x@, @y@ and @z@ separate the key material into three
615 * parts. Between the @k@ and @k + x@ is `my' contribution to
616 * the key material; between @k + x@ and @k + y@ is `your'
617 * contribution; and between @k + y@ and @k + z@ is a shared
618 * value we made together. These are used to construct two
619 * pairs of symmetric keys. Each pair consists of an encryption
620 * key and a message authentication key. One pair is used for
621 * outgoing messages, the other for incoming messages.
623 * The new key is marked so that it won't be selected for output
624 * by @ksl_encrypt@. You can still encrypt data with it by
625 * calling @ks_encrypt@ directly.
628 extern keyset *ks_gen(const void */*k*/,
629 size_t /*x*/, size_t /*y*/, size_t /*z*/,
632 /* --- @ks_tregen@ --- *
634 * Arguments: @keyset *ks@ = pointer to a keyset
636 * Returns: The time at which moves ought to be made to replace this key.
639 extern time_t ks_tregen(keyset */*ks*/);
641 /* --- @ks_activate@ --- *
643 * Arguments: @keyset *ks@ = pointer to a keyset
647 * Use: Activates a keyset, so that it can be used for encrypting
651 extern void ks_activate(keyset */*ks*/);
653 /* --- @ks_encrypt@ --- *
655 * Arguments: @keyset *ks@ = pointer to a keyset
656 * @unsigned ty@ = message type
657 * @buf *b@ = pointer to input buffer
658 * @buf *bb@ = pointer to output buffer
660 * Returns: Zero if OK, nonzero if the key needs replacing. If the
661 * encryption failed, the output buffer is broken and zero is
664 * Use: Encrypts a block of data using the key. Note that the `key
665 * ought to be replaced' notification is only ever given once
666 * for each key. Also note that this call forces a keyset to be
667 * used even if it's marked as not for data output.
670 extern int ks_encrypt(keyset */*ks*/, unsigned /*ty*/,
671 buf */*b*/, buf */*bb*/);
673 /* --- @ks_decrypt@ --- *
675 * Arguments: @keyset *ks@ = pointer to a keyset
676 * @unsigned ty@ = expected type code
677 * @buf *b@ = pointer to an input buffer
678 * @buf *bb@ = pointer to an output buffer
680 * Returns: Zero on success, or nonzero if there was some problem.
682 * Use: Attempts to decrypt a message using a given key. Note that
683 * requesting decryption with a key directly won't clear a
684 * marking that it's not for encryption.
687 extern int ks_decrypt(keyset */*ks*/, unsigned /*ty*/,
688 buf */*b*/, buf */*bb*/);
690 /* --- @ksl_free@ --- *
692 * Arguments: @keyset **ksroot@ = pointer to keyset list head
696 * Use: Frees (releases references to) all of the keys in a keyset.
699 extern void ksl_free(keyset **/*ksroot*/);
701 /* --- @ksl_link@ --- *
703 * Arguments: @keyset **ksroot@ = pointer to keyset list head
704 * @keyset *ks@ = pointer to a keyset
708 * Use: Links a keyset into a list. A keyset can only be on one list
709 * at a time. Bad things happen otherwise.
712 extern void ksl_link(keyset **/*ksroot*/, keyset */*ks*/);
714 /* --- @ksl_prune@ --- *
716 * Arguments: @keyset **ksroot@ = pointer to keyset list head
720 * Use: Prunes the keyset list by removing keys which mustn't be used
724 extern void ksl_prune(keyset **/*ksroot*/);
726 /* --- @ksl_encrypt@ --- *
728 * Arguments: @keyset **ksroot@ = pointer to keyset list head
729 * @unsigned ty@ = message type
730 * @buf *b@ = pointer to input buffer
731 * @buf *bb@ = pointer to output buffer
733 * Returns: Nonzero if a new key is needed.
735 * Use: Encrypts a packet.
738 extern int ksl_encrypt(keyset **/*ksroot*/, unsigned /*ty*/,
739 buf */*b*/, buf */*bb*/);
741 /* --- @ksl_decrypt@ --- *
743 * Arguments: @keyset **ksroot@ = pointer to keyset list head
744 * @unsigned ty@ = expected type code
745 * @buf *b@ = pointer to input buffer
746 * @buf *bb@ = pointer to output buffer
748 * Returns: Nonzero if the packet couldn't be decrypted.
750 * Use: Decrypts a packet.
753 extern int ksl_decrypt(keyset **/*ksroot*/, unsigned /*ty*/,
754 buf */*b*/, buf */*bb*/);
756 /*----- Challenges --------------------------------------------------------*/
760 * Arguments: @buf *b@ = where to put the challenge
762 * Returns: Zero if OK, nonzero on error.
764 * Use: Issues a new challenge.
767 extern int c_new(buf */*b*/);
769 /* --- @c_check@ --- *
771 * Arguments: @buf *b@ = where to find the challenge
773 * Returns: Zero if OK, nonzero if it didn't work.
775 * Use: Checks a challenge. On failure, the buffer is broken.
778 extern int c_check(buf */*b*/);
780 /*----- Administration interface ------------------------------------------*/
782 #define A_END ((char *)0)
784 /* --- @a_warn@ --- *
786 * Arguments: @const char *fmt@ = pointer to format string
787 * @...@ = other arguments
791 * Use: Informs all admin connections of a warning.
794 extern void a_warn(const char */*fmt*/, ...);
796 /* --- @a_notify@ --- *
798 * Arguments: @const char *fmt@ = pointer to format string
799 * @...@ = other arguments
803 * Use: Sends a notification to interested admin connections.
806 extern void a_notify(const char */*fmt*/, ...);
808 /* --- @a_create@ --- *
810 * Arguments: @int fd_in, fd_out@ = file descriptors to use
811 * @unsigned f@ = initial flags to set
815 * Use: Creates a new admin connection.
818 extern void a_create(int /*fd_in*/, int /*fd_out*/, unsigned /*f*/);
820 /* --- @a_quit@ --- *
826 * Use: Shuts things down nicely.
829 extern void a_quit(void);
831 /* --- @a_preselect@ --- *
837 * Use: Informs the admin module that we're about to select again,
838 * and that it should do cleanup things it has delayed until a
842 extern void a_preselect(void);
844 /* --- @a_daemon@ --- *
850 * Use: Informs the admin module that it's a daemon.
853 extern void a_daemon(void);
855 /* --- @a_init@ --- *
857 * Arguments: @const char *sock@ = socket name to create
861 * Use: Creates the admin listening socket.
864 extern void a_init(const char */*sock*/);
866 /*----- Peer management ---------------------------------------------------*/
868 /* --- @p_txstart@ --- *
870 * Arguments: @peer *p@ = pointer to peer block
871 * @unsigned msg@ = message type code
873 * Returns: A pointer to a buffer to write to.
875 * Use: Starts sending to a peer. Only one send can happen at a
879 extern buf *p_txstart(peer */*p*/, unsigned /*msg*/);
881 /* --- @p_txend@ --- *
883 * Arguments: @peer *p@ = pointer to peer block
887 * Use: Sends a packet to the peer.
890 extern void p_txend(peer */*p*/);
892 /* --- @p_pingsend@ --- *
894 * Arguments: @peer *p@ = destination peer
895 * @ping *pg@ = structure to fill in
896 * @unsigned type@ = message type
897 * @unsigned long timeout@ = how long to wait before giving up
898 * @void (*func)(int, void *)@ = callback function
899 * @void *arg@ = argument for callback
901 * Returns: Zero if successful, nonzero if it failed.
903 * Use: Sends a ping to a peer. Call @func@ with a nonzero argument
904 * if we get an answer within the timeout, or zero if no answer.
907 extern int p_pingsend(peer */*p*/, ping */*pg*/, unsigned /*type*/,
908 unsigned long /*timeout*/,
909 void (*/*func*/)(int, void *), void */*arg*/);
911 /* --- @p_pingdone@ --- *
913 * Arguments: @ping *p@ = ping structure
914 * @int rc@ = return code to pass on
918 * Use: Disposes of a ping structure, maybe sending a notification.
921 extern void p_pingdone(ping */*p*/, int /*rc*/);
923 /* --- @p_greet@ --- *
925 * Arguments: @peer *p@ = peer to send to
926 * @const void *c@ = pointer to challenge
927 * @size_t sz@ = size of challenge
931 * Use: Sends a greeting packet.
934 extern void p_greet(peer */*p*/, const void */*c*/, size_t /*sz*/);
938 * Arguments: @peer *p@ = pointer to peer block
939 * @buf *b@ = buffer containing incoming packet
943 * Use: Handles a packet which needs to be sent to a peer.
946 extern void p_tun(peer */*p*/, buf */*b*/);
948 /* --- @p_keyreload@ --- *
954 * Use: Forces a check of the daemon's keyring files.
957 extern void p_keyreload(void);
959 /* --- @p_interval@ --- *
965 * Use: Called periodically to do tidying.
968 extern void p_interval(void);
970 /* --- @p_stats@ --- *
972 * Arguments: @peer *p@ = pointer to a peer block
974 * Returns: A pointer to the peer's statistics.
977 extern stats *p_stats(peer */*p*/);
979 /* --- @p_ifname@ --- *
981 * Arguments: @peer *p@ = pointer to a peer block
983 * Returns: A pointer to the peer's interface name.
986 extern const char *p_ifname(peer */*p*/);
988 /* --- @p_setifname@ --- *
990 * Arguments: @peer *p@ = pointer to a peer block
991 * @const char *name@ = pointer to the new name
995 * Use: Changes the name held for a peer's interface.
998 extern void p_setifname(peer */*p*/, const char */*name*/);
1000 /* --- @p_addr@ --- *
1002 * Arguments: @peer *p@ = pointer to a peer block
1004 * Returns: A pointer to the peer's address.
1007 extern const addr *p_addr(peer */*p*/);
1009 /* --- @p_init@ --- *
1011 * Arguments: @struct in_addr addr@ = address to bind to
1012 * @unsigned port@ = port number to listen to
1016 * Use: Initializes the peer system; creates the socket.
1019 extern void p_init(struct in_addr /*addr*/, unsigned /*port*/);
1021 /* --- @p_port@ --- *
1025 * Returns: Port number used for socket.
1028 unsigned p_port(void);
1030 /* --- @p_create@ --- *
1032 * Arguments: @peerspec *spec@ = information about this peer
1034 * Returns: Pointer to the peer block, or null if it failed.
1036 * Use: Creates a new named peer block. No peer is actually attached
1040 extern peer *p_create(peerspec */*spec*/);
1042 /* --- @p_name@ --- *
1044 * Arguments: @peer *p@ = pointer to a peer block
1046 * Returns: A pointer to the peer's name.
1048 * Use: Equivalent to @p_spec(p)->name@.
1051 extern const char *p_name(peer */*p*/);
1053 /* --- @p_spec@ --- *
1055 * Arguments: @peer *p@ = pointer to a peer block
1057 * Returns: Pointer to the peer's specification
1060 extern const peerspec *p_spec(peer */*p*/);
1062 /* --- @p_find@ --- *
1064 * Arguments: @const char *name@ = name to look up
1066 * Returns: Pointer to the peer block, or null if not found.
1068 * Use: Finds a peer by name.
1071 extern peer *p_find(const char */*name*/);
1073 /* --- @p_destroy@ --- *
1075 * Arguments: @peer *p@ = pointer to a peer
1079 * Use: Destroys a peer.
1082 extern void p_destroy(peer */*p*/);
1084 /* --- @p_first@, @p_next@ --- *
1086 * Arguments: @peer *p@ = a peer block
1088 * Returns: @peer_first@ returns the first peer in some ordering;
1089 * @peer_next@ returns the peer following a given one in the
1090 * same ordering. Null is returned for the end of the list.
1093 extern peer *p_first(void);
1094 extern peer *p_next(peer */*p*/);
1096 /*----- Tunnel drivers ----------------------------------------------------*/
1099 extern const tunnel_ops tun_linux;
1103 extern const tunnel_ops tun_unet;
1107 extern const tunnel_ops tun_bsd;
1110 extern const tunnel_ops tun_slip;
1112 /*----- Other handy utilities ---------------------------------------------*/
1114 /* --- @mpstr@ --- *
1116 * Arguments: @mp *m@ = a multiprecision integer
1118 * Returns: A pointer to the integer's textual representation.
1120 * Use: Converts a multiprecision integer to a string. Corrupts
1124 extern const char *mpstr(mp */*m*/);
1126 /* --- @gestr@ --- *
1128 * Arguments: @group *g@ = a group
1129 * @ge *x@ = a group element
1131 * Returns: A pointer to the element's textual representation.
1133 * Use: Converts a group element to a string. Corrupts
1137 extern const char *gestr(group */*g*/, ge */*x*/);
1139 /* --- @timestr@ --- *
1141 * Arguments: @time_t t@ = a time to convert
1143 * Returns: A pointer to a textual representation of the time.
1145 * Use: Converts a time to a textual representation. Corrupts
1149 extern const char *timestr(time_t /*t*/);
1151 /* --- @mystrieq@ --- *
1153 * Arguments: @const char *x, *y@ = two strings
1155 * Returns: True if @x@ and @y are equal, up to case.
1158 extern int mystrieq(const char */*x*/, const char */*y*/);
1160 /* --- @seq_reset@ --- *
1162 * Arguments: @seqwin *s@ = sequence-checking window
1166 * Use: Resets a sequence number window.
1169 extern void seq_reset(seqwin */*s*/);
1171 /* --- @seq_check@ --- *
1173 * Arguments: @seqwin *s@ = sequence-checking window
1174 * @uint32 q@ = sequence number to check
1175 * @const char *service@ = service to report message from
1177 * Returns: A @SEQ_@ code.
1179 * Use: Checks a sequence number against the window, updating things
1183 extern int seq_check(seqwin */*s*/, uint32 /*q*/, const char */*service*/);
1185 /*----- That's all, folks -------------------------------------------------*/