3 * Main header file for TrIPE
5 * (c) 2001 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Trivial IP Encryption (TrIPE).
12 * TrIPE is free software: you can redistribute it and/or modify it under
13 * the terms of the GNU General Public License as published by the Free
14 * Software Foundation; either version 3 of the License, or (at your
15 * option) any later version.
17 * TrIPE is distributed in the hope that it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 * You should have received a copy of the GNU General Public License
23 * along with TrIPE. If not, see <https://www.gnu.org/licenses/>.
33 /*----- Header files ------------------------------------------------------*/
49 #include <sys/types.h>
56 #include <sys/socket.h>
58 #include <netinet/in.h>
59 #include <arpa/inet.h>
65 #include <mLib/alloc.h>
66 #include <mLib/arena.h>
67 #include <mLib/base64.h>
68 #include <mLib/bres.h>
69 #include <mLib/codec.h>
70 #include <mLib/daemonize.h>
71 #include <mLib/dstr.h>
73 #include <mLib/fdflags.h>
74 #include <mLib/fdpass.h>
75 #include <mLib/fwatch.h>
76 #include <mLib/hash.h>
77 #include <mLib/macros.h>
78 #include <mLib/mdup.h>
79 #include <mLib/mdwopt.h>
80 #include <mLib/quis.h>
81 #include <mLib/report.h>
83 #include <mLib/selbuf.h>
87 #include <mLib/trace.h>
89 #include <mLib/versioncmp.h>
91 #include <catacomb/buf.h>
92 #include <catacomb/ct.h>
94 #include <catacomb/chacha.h>
95 #include <catacomb/gcipher.h>
96 #include <catacomb/gmac.h>
97 #include <catacomb/grand.h>
98 #include <catacomb/key.h>
99 #include <catacomb/paranoia.h>
100 #include <catacomb/poly1305.h>
101 #include <catacomb/salsa20.h>
103 #include <catacomb/noise.h>
104 #include <catacomb/rand.h>
106 #include <catacomb/mp.h>
107 #include <catacomb/mpmont.h>
108 #include <catacomb/mprand.h>
109 #include <catacomb/dh.h>
110 #include <catacomb/ec.h>
111 #include <catacomb/ec-raw.h>
112 #include <catacomb/ec-keys.h>
113 #include <catacomb/x25519.h>
114 #include <catacomb/x448.h>
117 #include "protocol.h"
123 /*----- Magic numbers -----------------------------------------------------*/
125 /* --- Trace flags --- */
133 #define T_KEYEXCH 64u
134 #define T_KEYMGMT 128u
136 /* T_PRIVSEP in priv.h */
142 #define SEC(n) (n##u)
143 #define MIN(n) (n##u * 60u)
144 #define F_2P32 (65536.0*65536.0)
145 #define MEG(n) (n##ul * 1024ul * 1024ul)
147 /* --- Timing parameters --- */
149 #define T_EXP MIN(60) /* Expiry time for a key */
150 #define T_REGEN MIN(40) /* Regeneration time for a key */
152 #define T_VALID SEC(20) /* Challenge validity period */
153 #define T_RETRYMIN SEC(2) /* Minimum retry interval */
154 #define T_RETRYMAX MIN(5) /* Maximum retry interval */
155 #define T_RETRYGROW (5.0/4.0) /* Retry interval growth factor */
157 #define T_WOBBLE (1.0/3.0) /* Relative timer randomness */
159 /* --- Other things --- */
161 #define PKBUFSZ 65536
163 /*----- Cipher selections -------------------------------------------------*/
165 typedef struct keyset keyset;
166 typedef struct algswitch algswitch;
167 typedef struct kdata kdata;
168 typedef struct admin admin;
170 typedef struct dhgrp {
171 const struct dhops *ops;
175 typedef struct dhsc dhsc;
176 typedef struct dhge dhge;
179 DHFMT_STD, /* Fixed-width format, suitable for encryption */
180 DHFMT_HASH, /* Deterministic format, suitable for hashing */
181 DHFMT_VAR /* Variable-width-format, mostly a bad idea */
184 typedef struct bulkalgs {
185 const struct bulkops *ops;
188 typedef struct bulkctx {
189 const struct bulkops *ops;
192 typedef struct bulkchal {
193 const struct bulkops *ops;
199 typedef struct dhops {
202 int (*ldpriv)(key_file */*kf*/, key */*k*/, key_data */*d*/,
203 kdata */*kd*/, dstr */*t*/, dstr */*e*/);
204 /* Load a private key from @d@, storing the data in @kd@. The key's
205 * file and key object are in @kf@ and @k@, mostly in case its
206 * attributes are interesting; the key tag is in @t@; errors are
207 * reported by writing tokens to @e@ and returning nonzero.
210 int (*ldpub)(key_file */*kf*/, key */*k*/, key_data */*d*/,
211 kdata */*kd*/, dstr */*t*/, dstr */*e*/);
212 /* Load a public key from @d@, storing the data in @kd@. The key's
213 * file and key object are in @kf@ and @k@, mostly in case its
214 * attributes are interesting; the key tag is in @t@; errors are
215 * reported by writing tokens to @e@ and returning nonzero.
218 const char *(*checkgrp)(const dhgrp */*g*/);
219 /* Check that the group is valid; return null on success, or an error
223 void (*grpinfo)(const dhgrp */*g*/, admin */*a*/);
224 /* Report on the group to an admin client. */
226 T( void (*tracegrp)(const dhgrp */*g*/); )
227 /* Trace a description of the group. */
229 int (*samegrpp)(const dhgrp */*g*/, const dhgrp */*gg*/);
230 /* Return nonzero if the two group objects represent the same
234 void (*freegrp)(dhgrp */*g*/);
235 /* Free a group and the resources it holds. */
237 dhsc *(*ldsc)(const dhgrp */*g*/, const void */*p*/, size_t /*sz*/);
238 /* Load a scalar from @p@, @sz@ and return it. Return null on
242 int (*stsc)(const dhgrp */*g*/,
243 void */*p*/, size_t /*sz*/, const dhsc */*x*/);
244 /* Store a scalar at @p@, @sz@. Return nonzero on error. */
246 dhsc *(*randsc)(const dhgrp */*g*/);
247 /* Return a random scalar. */
249 T( const char *(*scstr)(const dhgrp */*g*/, const dhsc */*x*/); )
250 /* Return a human-readable representation of @x@; @buf_t@ may be used
254 void (*freesc)(const dhgrp */*g*/, dhsc */*x*/);
255 /* Free a scalar and the resources it holds. */
257 dhge *(*ldge)(const dhgrp */*g*/, buf */*b*/, int /*fmt*/);
258 /* Load a group element from @b@, encoded using format @fmt@. Return
262 int (*stge)(const dhgrp */*g*/, buf */*b*/,
263 const dhge */*Y*/, int /*fmt*/);
264 /* Store a group element in @b@, encoded using format @fmt@. Return
268 int (*checkge)(const dhgrp */*h*/, const dhge */*Y*/);
269 /* Check a group element for validity. Return zero if everything
270 * checks out; nonzero on failure.
273 int (*eq)(const dhgrp */*g*/, const dhge */*Y*/, const dhge */*Z*/);
274 /* Return nonzero if @Y@ and @Z@ are equal. */
276 dhge *(*mul)(const dhgrp */*g*/, const dhsc */*x*/, const dhge */*Y*/);
277 /* Multiply a group element by a scalar, resulting in a shared-secret
278 * group element. If @y@ is null, then multiply the well-known
282 T( const char *(*gestr)(const dhgrp */*g*/, const dhge */*Y*/); )
283 /* Return a human-readable representation of @Y@; @buf_t@ may be used
287 void (*freege)(const dhgrp */*g*/, dhge */*Y*/);
288 /* Free a group element and the resources it holds. */
292 typedef struct bulkops {
295 bulkalgs *(*getalgs)(const algswitch */*asw*/, dstr */*e*/,
296 key_file */*kf*/, key */*k*/);
297 /* Determine algorithms to use and return a @bulkalgs@ object
298 * representing the decision. On error, write tokens to @e@ and
302 T( void (*tracealgs)(const bulkalgs */*a*/); )
303 /* Write trace information about the algorithm selection. */
305 int (*checkalgs)(bulkalgs */*a*/, const algswitch */*asw*/, dstr */*e*/);
306 /* Check that the algorithms in @a@ and @asw@ are acceptable. On
307 * error, write tokens to @e@ and return @-1@; otherwise return zero.
310 int (*samealgsp)(const bulkalgs */*a*/, const bulkalgs */*aa*/);
311 /* If @a@ and @aa@ represent the same algorithm selection, return
312 * nonzero; if not, return zero.
315 void (*alginfo)(const bulkalgs */*a*/, admin */*adm*/);
316 /* Report on the algorithm selection to an admin client: call
317 * @a_info@ with appropriate key-value pairs.
320 size_t (*overhead)(const bulkalgs */*a*/);
321 /* Return the per-packet overhead of the bulk transform, in bytes. */
323 size_t (*expsz)(const bulkalgs */*a*/);
324 /* Return the total size limit for the bulk transform, in bytes,
325 * after which the keys must no longer be used.
328 bulkctx *(*genkeys)(const bulkalgs */*a*/, const struct rawkey */*rk*/);
329 /* Generate session keys and construct and return an appropriate
330 * context for using them, by calling @ks_derive@.
333 bulkchal *(*genchal)(const bulkalgs */*a*/);
334 /* Construct and return a challenge issuing and verification
335 * context with a fresh random key.
338 void (*freealgs)(bulkalgs */*a*/);
339 /* Release an algorithm selection object. (Associated bulk
340 * encryption contexts and challenge contexts may still exist and
341 * must remain valid.)
344 int (*encrypt)(bulkctx */*bc*/, unsigned /*ty*/,
345 buf */*b*/, buf */*bb*/, uint32 /*seq*/);
346 /* Encrypt the packet in @b@, with type @ty@ (which doesn't need
347 * encoding separately) and sequence number @seq@ (which must be
348 * recoverable by @decrypt@), and write the result to @bb@. On
349 * error, return a @KSERR_...@ code and/or break the output buffer.
352 int (*decrypt)(bulkctx */*bc*/, unsigned /*ty*/,
353 buf */*b*/, buf */*bb*/, uint32 */*seq*/);
354 /* Decrypt the packet in @b@, with type @ty@, writing the result to
355 * @bb@ and storing the incoming (claimed) sequence number in @seq@.
356 * On error, return a @KSERR_...@ code.
359 void (*freectx)(bulkctx */*a*/);
360 /* Release a bulk encryption context and the resources it holds. */
362 int (*chaltag)(bulkchal */*bc*/, const void */*m*/, size_t /*msz*/,
364 /* Calculate a tag for the challenge in @m@, @msz@, and write it to
365 * @t@. Return @-1@ on error, zero on success.
368 int (*chalvrf)(bulkchal */*bc*/, const void */*m*/, size_t /*msz*/,
370 /* Check the tag @t@ on @m@, @msz@: return zero if the tag is OK,
371 * nonzero if it's bad.
374 void (*freechal)(bulkchal */*bc*/);
375 /* Release a challenge context and the resources it holds. */
380 const gchash *h; size_t hashsz; /* Hash function */
381 const gccipher *mgf; /* Mask-generation function */
382 bulkalgs *bulk; /* Bulk crypto algorithms */
386 unsigned ref; /* Reference counter */
387 struct knode *kn; /* Pointer to cache entry */
388 char *tag; /* Full tag name of the key */
389 dhgrp *grp; /* The group we work in */
390 dhsc *k; /* The private key (or null) */
391 dhge *K; /* The public key */
392 time_t t_exp; /* Expiry time of the key */
393 algswitch algs; /* Collection of algorithms */
396 typedef struct knode {
397 sym_base _b; /* Symbol table intrusion */
398 unsigned f; /* Various flags */
399 #define KNF_BROKEN 1u /* Don't use this key any more */
400 struct keyhalf *kh; /* Pointer to the home keyhalf */
401 kdata *kd; /* Pointer to the key data */
404 #define MAXHASHSZ 64 /* Largest possible hash size */
406 #define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
408 extern const dhops dhtab[];
409 extern const bulkops bulktab[];
411 /*----- Data structures ---------------------------------------------------*/
413 /* --- The address-family table --- */
419 #define ENUM(af) AFIX_##af,
425 extern const struct addrfam {
430 /* --- Socket addresses --- *
432 * A magic union of supported socket addresses.
437 struct sockaddr_in sin;
440 /* --- Mapping keyed on addresses --- */
442 typedef struct addrmap {
447 typedef struct addrmap_base {
452 /* --- Sequence number checking --- */
454 typedef struct seqwin {
455 uint32 seq; /* First acceptable input sequence */
456 uint32 win; /* Window of acceptable numbers */
459 #define SEQ_WINSZ 32 /* Bits in sequence number window */
461 /* --- A symmetric keyset --- *
463 * A keyset contains a set of symmetric keys for encrypting and decrypting
464 * packets. Keysets are stored in a list, sorted in reverse order of
465 * creation, so that the most recent keyset (the one most likely to be used)
468 * Each keyset has a time limit and a data limit. The keyset is destroyed
469 * when either it has existed for too long, or it has been used to encrypt
470 * too much data. New key exchanges are triggered when keys are close to
474 enum { DIR_IN, DIR_OUT, NDIR };
477 struct keyset *next; /* Next active keyset in the list */
478 unsigned ref; /* Reference count for keyset */
479 struct peer *p; /* Pointer to peer structure */
480 time_t t_exp; /* Expiry time for this keyset */
481 unsigned long sz_exp, sz_regen; /* Data limits for the keyset */
482 T( unsigned seq; ) /* Sequence number for tracing */
483 unsigned f; /* Various useful flags */
484 bulkctx *bulk; /* Bulk crypto transform */
485 uint32 oseq; /* Outbound sequence number */
486 seqwin iseq; /* Inbound sequence number */
489 #define KSF_LISTEN 1u /* Don't encrypt packets yet */
490 #define KSF_LINK 2u /* Key is in a linked list */
492 #define KSERR_REGEN -1 /* Regenerate keys */
493 #define KSERR_NOKEYS -2 /* No keys left */
494 #define KSERR_DECRYPT -3 /* Unable to decrypt message */
495 #define KSERR_SEQ -4 /* Incorrect sequence number */
496 #define KSERR_MALFORMED -5 /* Input ciphertext is broken */
498 /* --- Key exchange --- *
500 * TrIPE uses the Wrestlers Protocol for its key exchange. The Wrestlers
501 * Protocol has a number of desirable features (e.g., perfect forward
502 * secrecy, and zero-knowledge authentication) which make it attractive for
503 * use in TrIPE. The Wrestlers Protocol was designed by Mark Wooding and
507 typedef struct retry {
508 double t; /* Current retry time */
513 typedef struct kxchal {
514 struct keyexch *kx; /* Pointer back to key exchange */
515 dhge *C; /* Responder's challenge */
516 dhge *R; /* My reply to the challenge */
517 keyset *ks; /* Pointer to temporary keyset */
518 unsigned f; /* Various useful flags */
519 sel_timer t; /* Response timer for challenge */
520 retry rs; /* Retry state */
521 octet hc[MAXHASHSZ]; /* Hash of his challenge */
522 octet ck[MAXHASHSZ]; /* His magical check value */
523 octet hswrq_in[MAXHASHSZ]; /* Inbound switch request message */
524 octet hswok_in[MAXHASHSZ]; /* Inbound switch confirmation */
525 octet hswrq_out[MAXHASHSZ]; /* Outbound switch request message */
526 octet hswok_out[MAXHASHSZ]; /* Outbound switch confirmation */
529 typedef struct keyexch {
530 struct peer *p; /* Pointer back to the peer */
531 kdata *kpriv; /* Private key and related info */
532 kdata *kpub; /* Peer's public key */
533 keyset **ks; /* Peer's list of keysets */
534 unsigned f; /* Various useful flags */
535 unsigned s; /* Current state in exchange */
536 sel_timer t; /* Timer for next exchange */
537 retry rs; /* Retry state */
538 dhsc *a; /* My temporary secret */
539 dhge *C; /* My challenge */
540 dhge *RX; /* The expected response */
541 unsigned nr; /* Number of extant responses */
542 time_t t_valid; /* When this exchange goes bad */
543 octet hc[MAXHASHSZ]; /* Hash of my challenge */
544 kxchal *r[KX_NCHAL]; /* Array of challenges */
547 #define KXF_TIMER 1u /* Waiting for a timer to go off */
548 #define KXF_DEAD 2u /* The key-exchanger isn't up */
549 #define KXF_PUBKEY 4u /* Key exchanger has a public key */
550 #define KXF_CORK 8u /* Don't send anything yet */
553 KXS_DEAD, /* Uninitialized state (magical) */
554 KXS_CHAL, /* Main answer-challenges state */
555 KXS_COMMIT, /* Committed: send switch request */
556 KXS_SWITCH /* Switched: send confirmation */
559 /* --- Tunnel structure --- *
561 * Used to maintain system-specific information about the tunnel interface.
564 typedef struct tunnel tunnel;
567 typedef struct tunnel_ops {
568 const char *name; /* Name of this tunnel driver */
569 unsigned flags; /* Various interesting flags */
570 #define TUNF_PRIVOPEN 1u /* Need helper to open file */
571 void (*init)(void); /* Initializes the system */
572 tunnel *(*create)(struct peer */*p*/, int /*fd*/, char **/*ifn*/);
573 /* Initializes a new tunnel */
574 void (*setifname)(tunnel */*t*/, const char */*ifn*/);
575 /* Notifies ifname change */
576 void (*inject)(tunnel */*t*/, buf */*b*/); /* Sends packet through if */
577 void (*destroy)(tunnel */*t*/); /* Destroys a tunnel */
580 #ifndef TUN_INTERNALS
581 struct tunnel { const tunnel_ops *ops; };
584 /* --- Peer statistics --- *
586 * Contains various interesting and not-so-interesting statistics about a
587 * peer. This is updated by various parts of the code. The format of the
588 * structure isn't considered private, and @p_stats@ returns a pointer to the
589 * statistics block for a given peer.
592 typedef struct stats {
593 unsigned long sz_in, sz_out; /* Size of all data in and out */
594 unsigned long sz_kxin, sz_kxout; /* Size of key exchange messages */
595 unsigned long sz_ipin, sz_ipout; /* Size of encapsulated IP packets */
596 time_t t_start, t_last, t_kx; /* Time peer created, last pk, kx */
597 unsigned long n_reject; /* Number of rejected packets */
598 unsigned long n_in, n_out; /* Number of packets in and out */
599 unsigned long n_kxin, n_kxout; /* Number of key exchange packets */
600 unsigned long n_ipin, n_ipout; /* Number of encrypted packets */
603 /* --- Peer structure --- *
605 * The main structure which glues everything else together.
608 typedef struct peerspec {
609 char *name; /* Peer's name */
610 char *privtag; /* Private key tag */
611 char *tag; /* Public key tag */
612 const tunnel_ops *tops; /* Tunnel operations */
613 unsigned long t_ka; /* Keep alive interval */
614 addr sa; /* Socket address to speak to */
615 unsigned f; /* Flags for the peer */
616 #define PSF_KXMASK 255u /* Key-exchange flags to set */
617 #define PSF_MOBILE 256u /* Address may change rapidly */
620 typedef struct peer_byname {
625 typedef struct peer_byaddr {
630 typedef struct peer {
631 peer_byname *byname; /* Lookup-by-name block */
632 peer_byaddr *byaddr; /* Lookup-by-address block */
633 struct ping *pings; /* Pings we're waiting for */
634 peerspec spec; /* Specifications for this peer */
635 int afix; /* Index of address family */
636 tunnel *t; /* Tunnel for local packets */
637 char *ifname; /* Interface name for tunnel */
638 keyset *ks; /* List head for keysets */
639 buf b; /* Buffer for sending packets */
640 stats st; /* Statistics */
641 keyexch kx; /* Key exchange protocol block */
642 sel_timer tka; /* Timer for keepalives */
645 typedef struct peer_iter { sym_iter i; } peer_iter;
647 typedef struct ping {
648 struct ping *next, *prev; /* Links to next and previous */
649 peer *p; /* Peer so we can free it */
650 unsigned msg; /* Kind of response expected */
651 uint32 id; /* Id so we can recognize response */
652 octet magic[32]; /* Some random data */
653 sel_timer t; /* Timeout for ping */
654 void (*func)(int /*rc*/, void */*arg*/); /* Function to call when done */
655 void *arg; /* Argument for callback */
666 /* --- Admin structure --- */
668 #define OBUFSZ 16384u
670 typedef struct obuf {
671 struct obuf *next; /* Next buffer in list */
672 char *p_in, *p_out; /* Pointers into the buffer */
673 char buf[OBUFSZ]; /* The actual buffer */
676 typedef struct oqueue {
677 obuf *hd, *tl; /* Head and tail pointers */
682 typedef struct admin_bgop {
683 struct admin_bgop *next, *prev; /* Links to next and previous */
684 struct admin *a; /* Owner job */
685 char *tag; /* Tag string for messages */
686 void (*cancel)(struct admin_bgop *); /* Destructor function */
689 typedef struct admin_resop {
690 admin_bgop bg; /* Background operation header */
691 char *addr; /* Hostname to be resolved */
692 bres_client r; /* Background resolver task */
693 sel_timer t; /* Timer for resolver */
694 addr sa; /* Socket address */
695 size_t sasz; /* Socket address size */
696 void (*func)(struct admin_resop *, int); /* Handler */
699 enum { ARES_OK, ARES_FAIL };
701 typedef struct admin_addop {
702 admin_resop r; /* Name resolution header */
703 peerspec peer; /* Peer pending creation */
706 typedef struct admin_pingop {
707 admin_bgop bg; /* Background operation header */
708 ping ping; /* Ping pending response */
709 struct timeval pingtime; /* Time last ping was sent */
712 typedef struct admin_service {
713 sym_base _b; /* Hash table base structure */
714 char *version; /* The provided version */
715 struct admin *prov; /* Which client provides me */
716 struct admin_service *next, *prev; /* Client's list of services */
719 typedef struct admin_svcop {
720 admin_bgop bg; /* Background operation header */
721 struct admin *prov; /* Client servicing this job */
722 unsigned index; /* This job's index */
723 struct admin_svcop *next, *prev; /* Links for provider's jobs */
726 typedef struct admin_jobentry {
727 unsigned short seq; /* Zero if unused */
729 admin_svcop *op; /* Operation, if slot in use, ... */
730 uint32 next; /* ... or index of next free slot */
734 typedef struct admin_jobtable {
735 uint32 n, sz; /* Used slots and table size */
736 admin_svcop *active; /* List of active jobs */
737 uint32 free; /* Index of first free slot */
738 admin_jobentry *v; /* And the big array of entries */
742 struct admin *next, *prev; /* Links to next and previous */
743 unsigned f; /* Various useful flags */
744 unsigned ref; /* Reference counter */
746 unsigned seq; /* Sequence number for tracing */
748 oqueue out; /* Output buffer list */
749 oqueue delay; /* Delayed output buffer list */
750 admin_bgop *bg; /* Backgrounded operations */
751 admin_service *svcs; /* Which services I provide */
752 admin_jobtable j; /* Table of outstanding jobs */
753 selbuf b; /* Line buffer for commands */
754 sel_file w; /* Selector for write buffering */
757 #define AF_DEAD 1u /* Destroy this admin block */
758 #define AF_CLOSE 2u /* Client closed connection */
759 #define AF_NOTE 4u /* Catch notifications */
760 #define AF_WARN 8u /* Catch warning messages */
762 # define AF_TRACE 16u /* Catch tracing */
764 #define AF_FOREGROUND 32u /* Quit server when client closes */
767 # define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN)
769 # define AF_ALLMSGS (AF_NOTE | AF_WARN)
772 /*----- Global variables --------------------------------------------------*/
774 extern sel_state sel; /* Global I/O event state */
775 extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ], buf_u[PKBUFSZ];
776 extern const tunnel_ops *tunnels[]; /* Table of tunnels (0-term) */
777 extern const tunnel_ops *tun_default; /* Default tunnel to use */
778 extern sel_file udpsock[NADDRFAM]; /* The master UDP sockets */
779 extern kdata *master; /* Default private key */
780 extern const char *tag_priv; /* Default private key tag */
783 extern const trace_opt tr_opts[]; /* Trace options array */
784 extern unsigned tr_flags; /* Trace options flags */
787 /*----- Other macros ------------------------------------------------------*/
790 do { rand_quick(RAND_GLOBAL); noise_timer(RAND_GLOBAL); } while (0)
792 /*----- Key management ----------------------------------------------------*/
794 /* --- @km_init@ --- *
796 * Arguments: @const char *privkr@ = private keyring file
797 * @const char *pubkr@ = public keyring file
798 * @const char *ptag@ = default private-key tag
802 * Use: Initializes the key-management machinery, loading the
803 * keyrings and so on.
806 extern void km_init(const char */*privkr*/, const char */*pubkr*/,
807 const char */*ptag*/);
809 /* --- @km_reload@ --- *
813 * Returns: Zero if OK, nonzero to force reloading of keys.
815 * Use: Checks the keyrings to see if they need reloading.
818 extern int km_reload(void);
820 /* --- @km_findpub@, @km_findpriv@ --- *
822 * Arguments: @const char *tag@ = key tag to load
824 * Returns: Pointer to the kdata object if successful, or null on error.
826 * Use: Fetches a public or private key from the keyring.
829 extern kdata *km_findpub(const char */*tag*/);
830 extern kdata *km_findpriv(const char */*tag*/);
832 /* --- @km_samealgsp@ --- *
834 * Arguments: @const kdata *kdx, *kdy@ = two key data objects
836 * Returns: Nonzero if their two algorithm selections are the same.
838 * Use: Checks sameness of algorithm selections: used to ensure that
839 * peers are using sensible algorithms.
842 extern int km_samealgsp(const kdata */*kdx*/, const kdata */*kdy*/);
844 /* --- @km_ref@ --- *
846 * Arguments: @kdata *kd@ = pointer to the kdata object
850 * Use: Claim a new reference to a kdata object.
853 extern void km_ref(kdata */*kd*/);
855 /* --- @km_unref@ --- *
857 * Arguments: @kdata *kd@ = pointer to the kdata object
861 * Use: Releases a reference to a kdata object.
864 extern void km_unref(kdata */*kd*/);
866 /* --- @km_tag@ --- *
868 * Arguments: @kdata *kd@ - pointer to the kdata object
870 * Returns: A pointer to the short tag by which the kdata was loaded.
873 extern const char *km_tag(kdata */*kd*/);
875 /*----- Key exchange ------------------------------------------------------*/
877 /* --- @kx_start@ --- *
879 * Arguments: @keyexch *kx@ = pointer to key exchange context
880 * @int forcep@ = nonzero to ignore the quiet timer
884 * Use: Stimulates a key exchange. If a key exchage is in progress,
885 * a new challenge is sent (unless the quiet timer forbids
886 * this); if no exchange is in progress, one is commenced.
889 extern void kx_start(keyexch */*kx*/, int /*forcep*/);
891 /* --- @kx_message@ --- *
893 * Arguments: @keyexch *kx@ = pointer to key exchange context
894 * @unsigned msg@ = the message code
895 * @buf *b@ = pointer to buffer containing the packet
899 * Use: Reads a packet containing key exchange messages and handles
903 extern void kx_message(keyexch */*kx*/, unsigned /*msg*/, buf */*b*/);
905 /* --- @kx_free@ --- *
907 * Arguments: @keyexch *kx@ = pointer to key exchange context
911 * Use: Frees everything in a key exchange context.
914 extern void kx_free(keyexch */*kx*/);
916 /* --- @kx_newkeys@ --- *
918 * Arguments: @keyexch *kx@ = pointer to key exchange context
922 * Use: Informs the key exchange module that its keys may have
923 * changed. If fetching the new keys fails, the peer will be
924 * destroyed, we log messages and struggle along with the old
928 extern void kx_newkeys(keyexch */*kx*/);
930 /* --- @kx_init@ --- *
932 * Arguments: @keyexch *kx@ = pointer to key exchange context
933 * @peer *p@ = pointer to peer context
934 * @keyset **ks@ = pointer to keyset list
935 * @unsigned f@ = various useful flags
937 * Returns: Zero if OK, nonzero if it failed.
939 * Use: Initializes a key exchange module. The module currently
940 * contains no keys, and will attempt to initiate a key
944 extern int kx_init(keyexch */*kx*/, peer */*p*/,
945 keyset **/*ks*/, unsigned /*f*/);
947 /*----- Keysets and symmetric cryptography --------------------------------*/
949 /* --- @ks_drop@ --- *
951 * Arguments: @keyset *ks@ = pointer to a keyset
955 * Use: Decrements a keyset's reference counter. If the counter hits
956 * zero, the keyset is freed.
959 extern void ks_drop(keyset */*ks*/);
961 /* --- @ks_derivekey@ --- *
963 * Arguments: @octet *k@ = pointer to an output buffer of at least
965 * @size_t ksz@ = actual size wanted (for tracing)
966 * @const struct rawkey *rk@ = a raw key, as passed into
968 * @int dir@ = direction for the key (@DIR_IN@ or @DIR_OUT@)
969 * @const char *what@ = label for the key (input to derivation)
973 * Use: Derives a session key, for use on incoming or outgoing data.
974 * This function is part of a private protocol between @ks_gen@
975 * and the bulk crypto transform @genkeys@ operation.
978 extern void ks_derivekey(octet */*k*/, size_t /*ksz*/,
979 const struct rawkey */*rk*/,
980 int /*dir*/, const char */*what*/);
982 /* --- @ks_gen@ --- *
984 * Arguments: @const void *k@ = pointer to key material
985 * @size_t x, y, z@ = offsets into key material (see below)
986 * @peer *p@ = pointer to peer information
988 * Returns: A pointer to the new keyset.
990 * Use: Derives a new keyset from the given key material. The
991 * offsets @x@, @y@ and @z@ separate the key material into three
992 * parts. Between the @k@ and @k + x@ is `my' contribution to
993 * the key material; between @k + x@ and @k + y@ is `your'
994 * contribution; and between @k + y@ and @k + z@ is a shared
995 * value we made together. These are used to construct two
996 * collections of symmetric keys: one for outgoing messages, the
997 * other for incoming messages.
999 * The new key is marked so that it won't be selected for output
1000 * by @ksl_encrypt@. You can still encrypt data with it by
1001 * calling @ks_encrypt@ directly.
1004 extern keyset *ks_gen(const void */*k*/,
1005 size_t /*x*/, size_t /*y*/, size_t /*z*/,
1008 /* --- @ks_activate@ --- *
1010 * Arguments: @keyset *ks@ = pointer to a keyset
1014 * Use: Activates a keyset, so that it can be used for encrypting
1015 * outgoing messages.
1018 extern void ks_activate(keyset */*ks*/);
1020 /* --- @ks_encrypt@ --- *
1022 * Arguments: @keyset *ks@ = pointer to a keyset
1023 * @unsigned ty@ = message type
1024 * @buf *b@ = pointer to input buffer
1025 * @buf *bb@ = pointer to output buffer
1027 * Returns: Zero if successful; @KSERR_REGEN@ if we should negotiate a
1028 * new key; @KSERR_NOKEYS@ if the key is not usable. Also
1029 * returns zero if there was insufficient buffer (but the output
1030 * buffer is broken in this case).
1032 * Use: Encrypts a block of data using the key. Note that the `key
1033 * ought to be replaced' notification is only ever given once
1034 * for each key. Also note that this call forces a keyset to be
1035 * used even if it's marked as not for data output.
1037 * The encryption transform is permitted to corrupt @buf_u@ for
1038 * its own purposes. Neither the source nor destination should
1039 * be within @buf_u@; and callers mustn't expect anything stored
1040 * in @buf_u@ to still
1043 extern int ks_encrypt(keyset */*ks*/, unsigned /*ty*/,
1044 buf */*b*/, buf */*bb*/);
1046 /* --- @ks_decrypt@ --- *
1048 * Arguments: @keyset *ks@ = pointer to a keyset
1049 * @unsigned ty@ = expected type code
1050 * @buf *b@ = pointer to an input buffer
1051 * @buf *bb@ = pointer to an output buffer
1053 * Returns: Zero on success; @KSERR_DECRYPT@ on failure. Also returns
1054 * zero if there was insufficient buffer (but the output buffer
1055 * is broken in this case).
1057 * Use: Attempts to decrypt a message using a given key. Note that
1058 * requesting decryption with a key directly won't clear a
1059 * marking that it's not for encryption.
1061 * The decryption transform is permitted to corrupt @buf_u@ for
1062 * its own purposes. Neither the source nor destination should
1063 * be within @buf_u@; and callers mustn't expect anything stored
1064 * in @buf_u@ to still
1067 extern int ks_decrypt(keyset */*ks*/, unsigned /*ty*/,
1068 buf */*b*/, buf */*bb*/);
1070 /* --- @ksl_free@ --- *
1072 * Arguments: @keyset **ksroot@ = pointer to keyset list head
1076 * Use: Frees (releases references to) all of the keys in a keyset.
1079 extern void ksl_free(keyset **/*ksroot*/);
1081 /* --- @ksl_link@ --- *
1083 * Arguments: @keyset **ksroot@ = pointer to keyset list head
1084 * @keyset *ks@ = pointer to a keyset
1088 * Use: Links a keyset into a list. A keyset can only be on one list
1089 * at a time. Bad things happen otherwise.
1092 extern void ksl_link(keyset **/*ksroot*/, keyset */*ks*/);
1094 /* --- @ksl_prune@ --- *
1096 * Arguments: @keyset **ksroot@ = pointer to keyset list head
1100 * Use: Prunes the keyset list by removing keys which mustn't be used
1104 extern void ksl_prune(keyset **/*ksroot*/);
1106 /* --- @ksl_encrypt@ --- *
1108 * Arguments: @keyset **ksroot@ = pointer to keyset list head
1109 * @unsigned ty@ = message type
1110 * @buf *b@ = pointer to input buffer
1111 * @buf *bb@ = pointer to output buffer
1113 * Returns: Zero if successful; @KSERR_REGEN@ if it's time to negotiate a
1114 * new key; @KSERR_NOKEYS@ if there are no suitable keys
1115 * available. Also returns zero if there was insufficient
1116 * buffer space (but the output buffer is broken in this case).
1118 * Use: Encrypts a packet.
1121 extern int ksl_encrypt(keyset **/*ksroot*/, unsigned /*ty*/,
1122 buf */*b*/, buf */*bb*/);
1124 /* --- @ksl_decrypt@ --- *
1126 * Arguments: @keyset **ksroot@ = pointer to keyset list head
1127 * @unsigned ty@ = expected type code
1128 * @buf *b@ = pointer to input buffer
1129 * @buf *bb@ = pointer to output buffer
1131 * Returns: Zero on success; @KSERR_DECRYPT@ on failure. Also returns
1132 * zero if there was insufficient buffer (but the output buffer
1133 * is broken in this case).
1135 * Use: Decrypts a packet.
1138 extern int ksl_decrypt(keyset **/*ksroot*/, unsigned /*ty*/,
1139 buf */*b*/, buf */*bb*/);
1141 /*----- Challenges --------------------------------------------------------*/
1143 /* --- @c_new@ --- *
1145 * Arguments: @buf *b@ = where to put the challenge
1147 * Returns: Zero if OK, nonzero on error.
1149 * Use: Issues a new challenge.
1152 extern int c_new(buf */*b*/);
1154 /* --- @c_check@ --- *
1156 * Arguments: @buf *b@ = where to find the challenge
1158 * Returns: Zero if OK, nonzero if it didn't work.
1160 * Use: Checks a challenge. On failure, the buffer is broken.
1163 extern int c_check(buf */*b*/);
1165 /*----- Administration interface ------------------------------------------*/
1167 #define A_END ((char *)0)
1169 /* --- @a_vformat@ --- *
1171 * Arguments: @dstr *d@ = where to leave the formatted message
1172 * @const char *fmt@ = pointer to format string
1173 * @va_list *ap@ = arguments in list
1177 * Use: Main message token formatting driver. The arguments are
1178 * interleaved formatting tokens and their parameters, finally
1179 * terminated by an entry @A_END@.
1181 * Tokens recognized:
1183 * * "*..." ... -- pretokenized @dstr_putf@-like string
1185 * * "?ADDR" SOCKADDR -- a socket address, to be converted
1187 * * "?B64" BUFFER SIZE -- binary data to be base64-encoded
1189 * * "?TOKENS" VECTOR -- null-terminated vector of tokens
1191 * * "?PEER" PEER -- peer's name
1193 * * "?ERRNO" ERRNO -- system error code
1195 * * "[!]..." ... -- @dstr_putf@-like string as single token
1198 extern void a_vformat(dstr */*d*/, const char */*fmt*/, va_list */*ap*/);
1200 /* --- @a_format@ --- *
1202 * Arguments: @dstr *d@ = where to leave the formatted message
1203 * @const char *fmt@ = pointer to format string
1207 * Use: Writes a tokenized message into a string, for later
1211 extern void EXECL_LIKE(0) a_format(dstr */*d*/, const char */*fmt*/, ...);
1213 /* --- @a_info@ --- *
1215 * Arguments: @admin *a@ = connection
1216 * @const char *fmt@ = format string
1217 * @...@ = other arguments
1221 * Use: Report information to an admin client.
1224 extern void EXECL_LIKE(0) a_info(admin */*a*/, const char */*fmt*/, ...);
1226 /* --- @a_warn@ --- *
1228 * Arguments: @const char *fmt@ = pointer to format string
1229 * @...@ = other arguments
1233 * Use: Informs all admin connections of a warning.
1236 extern void EXECL_LIKE(0) a_warn(const char */*fmt*/, ...);
1238 /* --- @a_notify@ --- *
1240 * Arguments: @const char *fmt@ = pointer to format string
1241 * @...@ = other arguments
1245 * Use: Sends a notification to interested admin connections.
1248 extern void EXECL_LIKE(0) a_notify(const char */*fmt*/, ...);
1250 /* --- @a_create@ --- *
1252 * Arguments: @int fd_in, fd_out@ = file descriptors to use
1253 * @unsigned f@ = initial flags to set
1257 * Use: Creates a new admin connection.
1260 extern void a_create(int /*fd_in*/, int /*fd_out*/, unsigned /*f*/);
1262 /* --- @a_quit@ --- *
1268 * Use: Shuts things down nicely.
1271 extern void a_quit(void);
1273 /* --- @a_preselect@ --- *
1279 * Use: Informs the admin module that we're about to select again,
1280 * and that it should do cleanup things it has delayed until a
1284 extern void a_preselect(void);
1286 /* --- @a_daemon@ --- *
1292 * Use: Informs the admin module that it's a daemon.
1295 extern void a_daemon(void);
1297 /* --- @a_init@ --- *
1299 * Arguments: @const char *sock@ = socket name to create
1300 * @uid_t u@ = user to own the socket
1301 * @gid_t g@ = group to own the socket
1302 * @mode_t m@ = permissions to set on the socket
1306 * Use: Creates the admin listening socket.
1309 extern void a_init(const char */*sock*/,
1310 uid_t /*u*/, gid_t /*g*/, mode_t /*m*/);
1312 /*----- Mapping with addresses as keys ------------------------------------*/
1314 /* --- @am_create@ --- *
1316 * Arguments: @addrmap *m@ = pointer to map
1320 * Use: Create an address map, properly set up.
1323 extern void am_create(addrmap */*m*/);
1325 /* --- @am_destroy@ --- *
1327 * Arguments: @addrmap *m@ = pointer to map
1331 * Use: Destroy an address map, throwing away all the entries.
1334 extern void am_destroy(addrmap */*m*/);
1336 /* --- @am_find@ --- *
1338 * Arguments: @addrmap *m@ = pointer to map
1339 * @const addr *a@ = address to look up
1340 * @size_t sz@ = size of block to allocate
1341 * @unsigned *f@ = where to store flags
1343 * Returns: Pointer to found item, or null.
1345 * Use: Finds a record with the given IP address, set @*f@ nonzero
1346 * and returns it. If @sz@ is zero, and no match was found,
1347 * return null; otherwise allocate a new block of @sz@ bytes,
1348 * clear @*f@ to zero and return the block pointer.
1351 extern void *am_find(addrmap */*m*/, const addr */*a*/,
1352 size_t /*sz*/, unsigned */*f*/);
1354 /* --- @am_remove@ --- *
1356 * Arguments: @addrmap *m@ = pointer to map
1357 * @void *i@ = pointer to the item
1361 * Use: Removes an item from the map.
1364 extern void am_remove(addrmap */*m*/, void */*i*/);
1366 /*----- Privilege separation ----------------------------------------------*/
1368 /* --- @ps_trace@ --- *
1370 * Arguments: @unsigned mask@ = trace mask to check
1371 * @const char *fmt@ = message format
1372 * @...@ = values for placeholders
1376 * Use: Writes a trace message.
1379 T( extern void PRINTF_LIKE(2, 3)
1380 ps_trace(unsigned /*mask*/, const char */*fmt*/, ...); )
1382 /* --- @ps_warn@ --- *
1384 * Arguments: @const char *fmt@ = message format
1385 * @...@ = values for placeholders
1389 * Use: Writes a warning message.
1392 extern void PRINTF_LIKE(1, 2) ps_warn(const char */*fmt*/, ...);
1394 /* --- @ps_tunfd@ --- *
1396 * Arguments: @const tunnel_ops *tops@ = pointer to tunnel operations
1397 * @char **ifn@ = where to put the interface name
1399 * Returns: The file descriptor, or @-1@ on error.
1401 * Use: Fetches a file descriptor for a tunnel driver.
1404 extern int ps_tunfd(const tunnel_ops */*tops*/, char **/*ifn*/);
1406 /* --- @ps_split@ --- *
1408 * Arguments: @int detachp@ = whether to detach the child from its terminal
1412 * Use: Separates off the privileged tunnel-opening service from the
1413 * rest of the server.
1416 extern void ps_split(int /*detachp*/);
1418 /* --- @ps_quit@ --- *
1424 * Use: Detaches from the helper process.
1427 extern void ps_quit(void);
1429 /*----- Peer management ---------------------------------------------------*/
1431 /* --- @p_updateaddr@ --- *
1433 * Arguments: @peer *p@ = pointer to peer block
1434 * @const addr *a@ = address to associate with this peer
1436 * Returns: Zero if the address was changed; @+1@ if it was already
1439 * Use: Updates our idea of @p@'s address.
1442 extern int p_updateaddr(peer */*p*/, const addr */*a*/);
1444 /* --- @p_txstart@ --- *
1446 * Arguments: @peer *p@ = pointer to peer block
1447 * @unsigned msg@ = message type code
1449 * Returns: A pointer to a buffer to write to.
1451 * Use: Starts sending to a peer. Only one send can happen at a
1455 extern buf *p_txstart(peer */*p*/, unsigned /*msg*/);
1457 /* --- @p_txend@ --- *
1459 * Arguments: @peer *p@ = pointer to peer block
1463 * Use: Sends a packet to the peer.
1466 extern void p_txend(peer */*p*/);
1468 /* --- @p_pingsend@ --- *
1470 * Arguments: @peer *p@ = destination peer
1471 * @ping *pg@ = structure to fill in
1472 * @unsigned type@ = message type
1473 * @unsigned long timeout@ = how long to wait before giving up
1474 * @void (*func)(int, void *)@ = callback function
1475 * @void *arg@ = argument for callback
1477 * Returns: Zero if successful, nonzero if it failed.
1479 * Use: Sends a ping to a peer. Call @func@ with a nonzero argument
1480 * if we get an answer within the timeout, or zero if no answer.
1483 extern int p_pingsend(peer */*p*/, ping */*pg*/, unsigned /*type*/,
1484 unsigned long /*timeout*/,
1485 void (*/*func*/)(int, void *), void */*arg*/);
1487 /* --- @p_pingdone@ --- *
1489 * Arguments: @ping *p@ = ping structure
1490 * @int rc@ = return code to pass on
1494 * Use: Disposes of a ping structure, maybe sending a notification.
1497 extern void p_pingdone(ping */*p*/, int /*rc*/);
1499 /* --- @p_greet@ --- *
1501 * Arguments: @peer *p@ = peer to send to
1502 * @const void *c@ = pointer to challenge
1503 * @size_t sz@ = size of challenge
1507 * Use: Sends a greeting packet.
1510 extern void p_greet(peer */*p*/, const void */*c*/, size_t /*sz*/);
1512 /* --- @p_tun@ --- *
1514 * Arguments: @peer *p@ = pointer to peer block
1515 * @buf *b@ = buffer containing incoming packet
1519 * Use: Handles a packet which needs to be sent to a peer.
1522 extern void p_tun(peer */*p*/, buf */*b*/);
1524 /* --- @p_keyreload@ --- *
1530 * Use: Forces a check of the daemon's keyring files.
1533 extern void p_keyreload(void);
1535 /* --- @p_interval@ --- *
1541 * Use: Called periodically to do tidying.
1544 extern void p_interval(void);
1546 /* --- @p_stats@ --- *
1548 * Arguments: @peer *p@ = pointer to a peer block
1550 * Returns: A pointer to the peer's statistics.
1553 extern stats *p_stats(peer */*p*/);
1555 /* --- @p_ifname@ --- *
1557 * Arguments: @peer *p@ = pointer to a peer block
1559 * Returns: A pointer to the peer's interface name.
1562 extern const char *p_ifname(peer */*p*/);
1564 /* --- @p_setifname@ --- *
1566 * Arguments: @peer *p@ = pointer to a peer block
1567 * @const char *name@ = pointer to the new name
1571 * Use: Changes the name held for a peer's interface.
1574 extern void p_setifname(peer */*p*/, const char */*name*/);
1576 /* --- @p_addr@ --- *
1578 * Arguments: @peer *p@ = pointer to a peer block
1580 * Returns: A pointer to the peer's address.
1583 extern const addr *p_addr(peer */*p*/);
1585 /* --- @p_init@ --- *
1587 * Arguments: @struct in_addr addr@ = address to bind to
1588 * @unsigned port@ = port number to listen to
1592 * Use: Initializes the peer system; creates the socket.
1595 extern void p_init(struct in_addr /*addr*/, unsigned /*port*/);
1597 /* --- @p_port@ --- *
1599 * Arguments: @int i@ = address family index to retrieve
1601 * Returns: Port number used for socket.
1604 extern unsigned p_port(int /*i*/);
1606 /* --- @p_create@ --- *
1608 * Arguments: @peerspec *spec@ = information about this peer
1610 * Returns: Pointer to the peer block, or null if it failed.
1612 * Use: Creates a new named peer block. No peer is actually attached
1616 extern peer *p_create(peerspec */*spec*/);
1618 /* --- @p_name@ --- *
1620 * Arguments: @peer *p@ = pointer to a peer block
1622 * Returns: A pointer to the peer's name.
1624 * Use: Equivalent to @p_spec(p)->name@.
1627 extern const char *p_name(peer */*p*/);
1629 /* --- @p_tag@ --- *
1631 * Arguments: @peer *p@ = pointer to a peer block
1633 * Returns: A pointer to the peer's public key tag.
1636 extern const char *p_tag(peer */*p*/);
1638 /* --- @p_privtag@ --- *
1640 * Arguments: @peer *p@ = pointer to a peer block
1642 * Returns: A pointer to the peer's private key tag.
1645 extern const char *p_privtag(peer */*p*/);
1647 /* --- @p_spec@ --- *
1649 * Arguments: @peer *p@ = pointer to a peer block
1651 * Returns: Pointer to the peer's specification
1654 extern const peerspec *p_spec(peer */*p*/);
1656 /* --- @p_findbyaddr@ --- *
1658 * Arguments: @const addr *a@ = address to look up
1660 * Returns: Pointer to the peer block, or null if not found.
1662 * Use: Finds a peer by address.
1665 extern peer *p_findbyaddr(const addr */*a*/);
1667 /* --- @p_find@ --- *
1669 * Arguments: @const char *name@ = name to look up
1671 * Returns: Pointer to the peer block, or null if not found.
1673 * Use: Finds a peer by name.
1676 extern peer *p_find(const char */*name*/);
1678 /* --- @p_destroy@ --- *
1680 * Arguments: @peer *p@ = pointer to a peer
1684 * Use: Destroys a peer.
1687 extern void p_destroy(peer */*p*/);
1689 /* --- @FOREACH_PEER@ --- *
1691 * Arguments: @p@ = name to bind to each peer
1692 * @stuff@ = thing to do for each item
1694 * Use: Does something for each current peer.
1697 #define FOREACH_PEER(p, stuff) do { \
1700 for (p_mkiter(&i_); (p = p_next(&i_)) != 0; ) stuff \
1703 /* --- @p_mkiter@ --- *
1705 * Arguments: @peer_iter *i@ = pointer to an iterator
1709 * Use: Initializes the iterator.
1712 extern void p_mkiter(peer_iter */*i*/);
1714 /* --- @p_next@ --- *
1716 * Arguments: @peer_iter *i@ = pointer to an iterator
1718 * Returns: Next peer, or null if at the end.
1720 * Use: Returns the next peer.
1723 extern peer *p_next(peer_iter */*i*/);
1725 /*----- Tunnel drivers ----------------------------------------------------*/
1728 extern const tunnel_ops tun_linux;
1732 extern const tunnel_ops tun_unet;
1736 extern const tunnel_ops tun_bsd;
1739 extern const tunnel_ops tun_slip;
1741 /*----- Other handy utilities ---------------------------------------------*/
1743 /* --- @timestr@ --- *
1745 * Arguments: @time_t t@ = a time to convert
1747 * Returns: A pointer to a textual representation of the time.
1749 * Use: Converts a time to a textual representation. Corrupts
1753 extern const char *timestr(time_t /*t*/);
1755 /* --- @mystrieq@ --- *
1757 * Arguments: @const char *x, *y@ = two strings
1759 * Returns: True if @x@ and @y are equal, up to case.
1762 extern int mystrieq(const char */*x*/, const char */*y*/);
1766 * Arguments: @int af@ = an address family code
1768 * Returns: The index of the address family's record in @aftab@, or @-1@.
1771 extern int afix(int af);
1773 /* --- @addrsz@ --- *
1775 * Arguments: @const addr *a@ = a network address
1777 * Returns: The size of the address, for passing into the sockets API.
1780 extern socklen_t addrsz(const addr */*a*/);
1782 /* --- @seq_reset@ --- *
1784 * Arguments: @seqwin *s@ = sequence-checking window
1788 * Use: Resets a sequence number window.
1791 extern void seq_reset(seqwin */*s*/);
1793 /* --- @seq_check@ --- *
1795 * Arguments: @seqwin *s@ = sequence-checking window
1796 * @uint32 q@ = sequence number to check
1797 * @const char *service@ = service to report message from
1799 * Returns: A @SEQ_@ code.
1801 * Use: Checks a sequence number against the window, updating things
1805 extern int seq_check(seqwin */*s*/, uint32 /*q*/, const char */*service*/);
1807 /*----- That's all, folks -------------------------------------------------*/