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/dstr.h>
73 #include <mLib/fdflags.h>
74 #include <mLib/fwatch.h>
75 #include <mLib/mdwopt.h>
76 #include <mLib/quis.h>
77 #include <mLib/report.h>
79 #include <mLib/selbuf.h>
83 #include <mLib/trace.h>
86 #include <catacomb/buf.h>
88 #include <catacomb/gcipher.h>
89 #include <catacomb/gmac.h>
90 #include <catacomb/grand.h>
91 #include <catacomb/key.h>
92 #include <catacomb/paranoia.h>
94 #include <catacomb/noise.h>
95 #include <catacomb/rand.h>
97 #include <catacomb/mp.h>
98 #include <catacomb/mprand.h>
99 #include <catacomb/dh.h>
100 #include <catacomb/ec.h>
101 #include <catacomb/ec-keys.h>
102 #include <catacomb/group.h>
104 #include "protocol.h"
109 /*----- Magic numbers -----------------------------------------------------*/
111 /* --- Trace flags --- */
119 #define T_KEYEXCH 64u
120 #define T_KEYMGMT 128u
127 #define SEC(n) (n##u)
128 #define MIN(n) (n##u * 60u)
129 #define MEG(n) (n##ul * 1024ul * 1024ul)
131 /* --- Other things --- */
133 #define PKBUFSZ 65536
135 /*----- Cipher selections -------------------------------------------------*/
137 typedef struct algswitch
{
138 const gccipher
*c
; /* Symmetric encryption scheme */
139 const gccipher
*mgf
; /* Mask-generation function */
140 const gchash
*h
; /* Hash function */
141 const gcmac
*m
; /* Message authentication code */
142 size_t hashsz
; /* Hash output size */
143 size_t tagsz
; /* Length to truncate MAC tags */
144 size_t cksz
, mksz
; /* Key lengths for @c@ and @m@ */
147 extern algswitch algs
;
149 #define MAXHASHSZ 64 /* Largest possible hash size */
151 #define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
153 /*----- Data structures ---------------------------------------------------*/
155 /* --- Socket addresses --- *
157 * A magic union of supported socket addresses.
162 struct sockaddr_in sin
;
165 /* --- Sequence number checking --- */
167 typedef struct seqwin
{
168 uint32 seq
; /* First acceptable input sequence */
169 uint32 win
; /* Window of acceptable numbers */
172 #define SEQ_WINSZ 32 /* Bits in sequence number window */
174 /* --- A symmetric keyset --- *
176 * A keyset contains a set of symmetric keys for encrypting and decrypting
177 * packets. Keysets are stored in a list, sorted in reverse order of
178 * creation, so that the most recent keyset (the one most likely to be used)
181 * Each keyset has a time limit and a data limit. The keyset is destroyed
182 * when either it has existed for too long, or it has been used to encrypt
183 * too much data. New key exchanges are triggered when keys are close to
187 typedef struct keyset
{
188 struct keyset
*next
; /* Next active keyset in the list */
189 unsigned ref
; /* Reference count for keyset */
190 struct peer
*p
; /* Pointer to peer structure */
191 time_t t_exp
; /* Expiry time for this keyset */
192 unsigned long sz_exp
; /* Data limit for the keyset */
193 T( unsigned seq
; ) /* Sequence number for tracing */
194 unsigned f
; /* Various useful flags */
195 gcipher
*cin
, *cout
; /* Keyset ciphers for encryption */
196 size_t tagsz
; /* Length to truncate MAC tags */
197 gmac
*min
, *mout
; /* Keyset MACs for integrity */
198 uint32 oseq
; /* Outbound sequence number */
199 seqwin iseq
; /* Inbound sequence number */
202 #define KSF_LISTEN 1u /* Don't encrypt packets yet */
203 #define KSF_LINK 2u /* Key is in a linked list */
205 /* --- Key exchange --- *
207 * TrIPE uses the Wrestlers Protocol for its key exchange. The Wrestlers
208 * Protocol has a number of desirable features (e.g., perfect forward
209 * secrecy, and zero-knowledge authentication) which make it attractive for
210 * use in TrIPE. The Wrestlers Protocol was designed by Mark Wooding and
216 typedef struct kxchal
{
217 struct keyexch
*kx
; /* Pointer back to key exchange */
218 ge
*c
; /* Responder's challenge */
219 ge
*r
; /* My reply to the challenge */
220 keyset
*ks
; /* Pointer to temporary keyset */
221 unsigned f
; /* Various useful flags */
222 sel_timer t
; /* Response timer for challenge */
223 octet hc
[MAXHASHSZ
]; /* Hash of his challenge */
224 octet ck
[MAXHASHSZ
]; /* His magical check value */
225 octet hswrq_in
[MAXHASHSZ
]; /* Inbound switch request message */
226 octet hswok_in
[MAXHASHSZ
]; /* Inbound switch confirmation */
227 octet hswrq_out
[MAXHASHSZ
]; /* Outbound switch request message */
228 octet hswok_out
[MAXHASHSZ
]; /* Outbound switch confirmation */
231 typedef struct keyexch
{
232 struct peer
*p
; /* Pointer back to the peer */
233 keyset
**ks
; /* Peer's list of keysets */
234 unsigned f
; /* Various useful flags */
235 unsigned s
; /* Current state in exchange */
236 sel_timer t
; /* Timer for next exchange */
237 ge
*kpub
; /* Peer's public key */
238 time_t texp_kpub
; /* Expiry time for public key */
239 mp
*alpha
; /* My temporary secret */
240 ge
*c
; /* My challenge */
241 ge
*rx
; /* The expected response */
242 unsigned nr
; /* Number of extant responses */
243 time_t t_valid
; /* When this exchange goes bad */
244 octet hc
[MAXHASHSZ
]; /* Hash of my challenge */
245 kxchal
*r
[KX_NCHAL
]; /* Array of challenges */
248 #define KXF_TIMER 1u /* Waiting for a timer to go off */
249 #define KXF_DEAD 2u /* The key-exchanger isn't up */
250 #define KXF_PUBKEY 4u /* Key exchanger has a public key */
253 KXS_DEAD
, /* Uninitialized state (magical) */
254 KXS_CHAL
, /* Main answer-challenges state */
255 KXS_COMMIT
, /* Committed: send switch request */
256 KXS_SWITCH
/* Switched: send confirmation */
259 /* --- Tunnel structure --- *
261 * Used to maintain system-specific information about the tunnel interface.
264 typedef struct tunnel tunnel
;
267 typedef struct tunnel_ops
{
268 const char *name
; /* Name of this tunnel driver */
269 void (*init
)(void); /* Initializes the system */
270 tunnel
*(*create
)(struct peer */
*p*/
); /* Initializes a new tunnel */
271 const char *(*ifname
)(tunnel */
*t*/
); /* Returns tunnel's interface name */
272 void (*inject
)(tunnel */
*t*/
, buf */
*b*/
); /* Sends packet through if */
273 void (*destroy
)(tunnel */
*t*/
); /* Destroys a tunnel */
276 #ifndef TUN_INTERNALS
277 struct tunnel
{ const tunnel_ops
*ops
; };
280 /* --- Peer statistics --- *
282 * Contains various interesting and not-so-interesting statistics about a
283 * peer. This is updated by various parts of the code. The format of the
284 * structure isn't considered private, and @p_stats@ returns a pointer to the
285 * statistics block for a given peer.
288 typedef struct stats
{
289 unsigned long sz_in
, sz_out
; /* Size of all data in and out */
290 unsigned long sz_kxin
, sz_kxout
; /* Size of key exchange messages */
291 unsigned long sz_ipin
, sz_ipout
; /* Size of encapsulated IP packets */
292 time_t t_start
, t_last
, t_kx
; /* Time peer created, last pk, kx */
293 unsigned long n_reject
; /* Number of rejected packets */
294 unsigned long n_in
, n_out
; /* Number of packets in and out */
295 unsigned long n_kxin
, n_kxout
; /* Number of key exchange packets */
296 unsigned long n_ipin
, n_ipout
; /* Number of encrypted packets */
299 /* --- Peer structure --- *
301 * The main structure which glues everything else together.
304 typedef struct peerspec
{
305 char *name
; /* Peer's name */
306 const tunnel_ops
*tops
; /* Tunnel operations */
307 unsigned long t_ka
; /* Keep alive interval */
308 addr sa
; /* Socket address to speak to */
309 size_t sasz
; /* Socket address size */
312 typedef struct peer
{
313 struct peer
*next
, *prev
; /* Links to next and previous */
314 struct ping
*pings
; /* Pings we're waiting for */
315 peerspec spec
; /* Specifications for this peer */
316 tunnel
*t
; /* Tunnel for local packets */
317 char *ifname
; /* Interface name for tunnel */
318 keyset
*ks
; /* List head for keysets */
319 buf b
; /* Buffer for sending packets */
320 stats st
; /* Statistics */
321 keyexch kx
; /* Key exchange protocol block */
322 sel_timer tka
; /* Timer for keepalives */
325 typedef struct ping
{
326 struct ping
*next
, *prev
; /* Links to next and previous */
327 peer
*p
; /* Peer so we can free it */
328 unsigned msg
; /* Kind of response expected */
329 uint32 id
; /* Id so we can recognize response */
330 octet magic
[32]; /* Some random data */
331 sel_timer t
; /* Timeout for ping */
332 void (*func
)(int /*rc*/, void */
*arg*/
); /* Function to call when done */
333 void *arg
; /* Argument for callback */
344 /* --- Admin structure --- */
346 #define OBUFSZ 16384u
348 typedef struct obuf
{
349 struct obuf
*next
; /* Next buffer in list */
350 char *p_in
, *p_out
; /* Pointers into the buffer */
351 char buf
[OBUFSZ
]; /* The actual buffer */
354 typedef struct oqueue
{
355 obuf
*hd
, *tl
; /* Head and tail pointers */
360 typedef struct admin_bgop
{
361 struct admin_bgop
*next
, *prev
; /* Links to next and previous */
362 struct admin
*a
; /* Owner job */
363 char *tag
; /* Tag string for messages */
364 void (*cancel
)(struct admin_bgop
*); /* Destructor function */
367 typedef struct admin_resop
{
368 admin_bgop bg
; /* Background operation header */
369 char *addr
; /* Hostname to be resolved */
370 bres_client r
; /* Background resolver task */
371 sel_timer t
; /* Timer for resolver */
372 addr sa
; /* Socket address */
373 size_t sasz
; /* Socket address size */
374 void (*func
)(struct admin_resop
*, int); /* Handler */
377 enum { ARES_OK
, ARES_FAIL
};
379 typedef struct admin_addop
{
380 admin_resop r
; /* Name resolution header */
381 peerspec peer
; /* Peer pending creation */
384 typedef struct admin_greetop
{
385 admin_resop r
; /* Name resolution header */
386 void *c
; /* Challenge block */
387 size_t sz
; /* Length of challenge */
390 typedef struct admin_pingop
{
391 admin_bgop bg
; /* Background operation header */
392 ping ping
; /* Ping pending response */
393 struct timeval pingtime
; /* Time last ping was sent */
396 typedef struct admin_service
{
397 sym_base _b
; /* Hash table base structure */
398 char *version
; /* The provided version */
399 struct admin
*prov
; /* Which client provides me */
400 struct admin_service
*next
, *prev
; /* Client's list of services */
403 typedef struct admin
{
404 struct admin
*next
, *prev
; /* Links to next and previous */
405 unsigned f
; /* Various useful flags */
406 unsigned ref
; /* Reference counter */
408 unsigned seq
; /* Sequence number for tracing */
410 oqueue out
; /* Output buffer list */
411 oqueue delay
; /* Delayed output buffer list */
412 admin_bgop
*bg
; /* Backgrounded operations */
413 admin_service
*svcs
; /* Which services I provide */
414 selbuf b
; /* Line buffer for commands */
415 sel_file w
; /* Selector for write buffering */
418 #define AF_DEAD 1u /* Destroy this admin block */
419 #define AF_CLOSE 2u /* Client closed connection */
420 #define AF_NOTE 4u /* Catch notifications */
421 #define AF_WARN 8u /* Catch warning messages */
423 #define AF_TRACE 16u /* Catch tracing */
427 # define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN)
429 # define AF_ALLMSGS (AF_NOTE | AF_WARN)
432 /*----- Global variables --------------------------------------------------*/
434 extern sel_state sel
; /* Global I/O event state */
435 extern group
*gg
; /* The group we work in */
436 extern size_t indexsz
; /* Size of exponent for the group */
437 extern mp
*kpriv
; /* Our private key */
438 extern ge
*kpub
; /* Our public key */
439 extern octet buf_i
[PKBUFSZ
], buf_o
[PKBUFSZ
], buf_t
[PKBUFSZ
];
440 extern const tunnel_ops
*tunnels
[]; /* Table of tunnels (0-term) */
441 extern const tunnel_ops
*tun_default
; /* Default tunnel to use */
444 extern const trace_opt tr_opts
[]; /* Trace options array */
445 extern unsigned tr_flags
; /* Trace options flags */
448 /*----- Other macros ------------------------------------------------------*/
450 #define TIMER noise_timer(RAND_GLOBAL)
452 /*----- Key management ----------------------------------------------------*/
454 /* --- @km_reload@ --- *
458 * Returns: Zero if OK, nonzero to force reloading of keys.
460 * Use: Checks the keyrings to see if they need reloading.
463 extern int km_reload(void);
465 /* --- @km_init@ --- *
467 * Arguments: @const char *kr_priv@ = private keyring file
468 * @const char *kr_pub@ = public keyring file
469 * @const char *tag@ = tag to load
473 * Use: Initializes, and loads the private key.
476 extern void km_init(const char */
*kr_priv*/
, const char */
*kr_pub*/
,
477 const char */
*tag*/
);
479 /* --- @km_getpubkey@ --- *
481 * Arguments: @const char *tag@ = public key tag to load
482 * @ge *kpub@ = where to put the public key
483 * @time_t *t_exp@ = where to put the expiry time
485 * Returns: Zero if OK, nonzero if it failed.
487 * Use: Fetches a public key from the keyring.
490 extern int km_getpubkey(const char */
*tag*/
, ge */
*kpub*/
,
493 /*----- Key exchange ------------------------------------------------------*/
495 /* --- @kx_start@ --- *
497 * Arguments: @keyexch *kx@ = pointer to key exchange context
498 * @int forcep@ = nonzero to ignore the quiet timer
502 * Use: Stimulates a key exchange. If a key exchage is in progress,
503 * a new challenge is sent (unless the quiet timer forbids
504 * this); if no exchange is in progress, one is commenced.
507 extern void kx_start(keyexch */
*kx*/
, int /*forcep*/);
509 /* --- @kx_message@ --- *
511 * Arguments: @keyexch *kx@ = pointer to key exchange context
512 * @unsigned msg@ = the message code
513 * @buf *b@ = pointer to buffer containing the packet
517 * Use: Reads a packet containing key exchange messages and handles
521 extern void kx_message(keyexch */
*kx*/
, unsigned /*msg*/, buf */
*b*/
);
523 /* --- @kx_free@ --- *
525 * Arguments: @keyexch *kx@ = pointer to key exchange context
529 * Use: Frees everything in a key exchange context.
532 extern void kx_free(keyexch */
*kx*/
);
534 /* --- @kx_newkeys@ --- *
536 * Arguments: @keyexch *kx@ = pointer to key exchange context
540 * Use: Informs the key exchange module that its keys may have
541 * changed. If fetching the new keys fails, the peer will be
542 * destroyed, we log messages and struggle along with the old
546 extern void kx_newkeys(keyexch */
*kx*/
);
548 /* --- @kx_init@ --- *
550 * Arguments: @keyexch *kx@ = pointer to key exchange context
551 * @peer *p@ = pointer to peer context
552 * @keyset **ks@ = pointer to keyset list
554 * Returns: Zero if OK, nonzero if it failed.
556 * Use: Initializes a key exchange module. The module currently
557 * contains no keys, and will attempt to initiate a key
561 extern int kx_init(keyexch */
*kx*/
, peer */
*p*/
, keyset
**/
*ks*/
);
563 /*----- Keysets and symmetric cryptography --------------------------------*/
565 /* --- @ks_drop@ --- *
567 * Arguments: @keyset *ks@ = pointer to a keyset
571 * Use: Decrements a keyset's reference counter. If the counter hits
572 * zero, the keyset is freed.
575 extern void ks_drop(keyset */
*ks*/
);
577 /* --- @ks_gen@ --- *
579 * Arguments: @const void *k@ = pointer to key material
580 * @size_t x, y, z@ = offsets into key material (see below)
581 * @peer *p@ = pointer to peer information
583 * Returns: A pointer to the new keyset.
585 * Use: Derives a new keyset from the given key material. The
586 * offsets @x@, @y@ and @z@ separate the key material into three
587 * parts. Between the @k@ and @k + x@ is `my' contribution to
588 * the key material; between @k + x@ and @k + y@ is `your'
589 * contribution; and between @k + y@ and @k + z@ is a shared
590 * value we made together. These are used to construct two
591 * pairs of symmetric keys. Each pair consists of an encryption
592 * key and a message authentication key. One pair is used for
593 * outgoing messages, the other for incoming messages.
595 * The new key is marked so that it won't be selected for output
596 * by @ksl_encrypt@. You can still encrypt data with it by
597 * calling @ks_encrypt@ directly.
600 extern keyset
*ks_gen(const void */
*k*/
,
601 size_t /*x*/, size_t /*y*/, size_t /*z*/,
604 /* --- @ks_tregen@ --- *
606 * Arguments: @keyset *ks@ = pointer to a keyset
608 * Returns: The time at which moves ought to be made to replace this key.
611 extern time_t ks_tregen(keyset */
*ks*/
);
613 /* --- @ks_activate@ --- *
615 * Arguments: @keyset *ks@ = pointer to a keyset
619 * Use: Activates a keyset, so that it can be used for encrypting
623 extern void ks_activate(keyset */
*ks*/
);
625 /* --- @ks_encrypt@ --- *
627 * Arguments: @keyset *ks@ = pointer to a keyset
628 * @unsigned ty@ = message type
629 * @buf *b@ = pointer to input buffer
630 * @buf *bb@ = pointer to output buffer
632 * Returns: Zero if OK, nonzero if the key needs replacing. If the
633 * encryption failed, the output buffer is broken and zero is
636 * Use: Encrypts a block of data using the key. Note that the `key
637 * ought to be replaced' notification is only ever given once
638 * for each key. Also note that this call forces a keyset to be
639 * used even if it's marked as not for data output.
642 extern int ks_encrypt(keyset */
*ks*/
, unsigned /*ty*/,
643 buf */
*b*/
, buf */
*bb*/
);
645 /* --- @ks_decrypt@ --- *
647 * Arguments: @keyset *ks@ = pointer to a keyset
648 * @unsigned ty@ = expected type code
649 * @buf *b@ = pointer to an input buffer
650 * @buf *bb@ = pointer to an output buffer
652 * Returns: Zero on success, or nonzero if there was some problem.
654 * Use: Attempts to decrypt a message using a given key. Note that
655 * requesting decryption with a key directly won't clear a
656 * marking that it's not for encryption.
659 extern int ks_decrypt(keyset */
*ks*/
, unsigned /*ty*/,
660 buf */
*b*/
, buf */
*bb*/
);
662 /* --- @ksl_free@ --- *
664 * Arguments: @keyset **ksroot@ = pointer to keyset list head
668 * Use: Frees (releases references to) all of the keys in a keyset.
671 extern void ksl_free(keyset
**/
*ksroot*/
);
673 /* --- @ksl_link@ --- *
675 * Arguments: @keyset **ksroot@ = pointer to keyset list head
676 * @keyset *ks@ = pointer to a keyset
680 * Use: Links a keyset into a list. A keyset can only be on one list
681 * at a time. Bad things happen otherwise.
684 extern void ksl_link(keyset
**/
*ksroot*/
, keyset */
*ks*/
);
686 /* --- @ksl_prune@ --- *
688 * Arguments: @keyset **ksroot@ = pointer to keyset list head
692 * Use: Prunes the keyset list by removing keys which mustn't be used
696 extern void ksl_prune(keyset
**/
*ksroot*/
);
698 /* --- @ksl_encrypt@ --- *
700 * Arguments: @keyset **ksroot@ = pointer to keyset list head
701 * @unsigned ty@ = message type
702 * @buf *b@ = pointer to input buffer
703 * @buf *bb@ = pointer to output buffer
705 * Returns: Nonzero if a new key is needed.
707 * Use: Encrypts a packet.
710 extern int ksl_encrypt(keyset
**/
*ksroot*/
, unsigned /*ty*/,
711 buf */
*b*/
, buf */
*bb*/
);
713 /* --- @ksl_decrypt@ --- *
715 * Arguments: @keyset **ksroot@ = pointer to keyset list head
716 * @unsigned ty@ = expected type code
717 * @buf *b@ = pointer to input buffer
718 * @buf *bb@ = pointer to output buffer
720 * Returns: Nonzero if the packet couldn't be decrypted.
722 * Use: Decrypts a packet.
725 extern int ksl_decrypt(keyset
**/
*ksroot*/
, unsigned /*ty*/,
726 buf */
*b*/
, buf */
*bb*/
);
728 /*----- Challenges --------------------------------------------------------*/
732 * Arguments: @buf *b@ = where to put the challenge
734 * Returns: Zero if OK, nonzero on error.
736 * Use: Issues a new challenge.
739 extern int c_new(buf */
*b*/
);
741 /* --- @c_check@ --- *
743 * Arguments: @buf *b@ = where to find the challenge
745 * Returns: Zero if OK, nonzero if it didn't work.
747 * Use: Checks a challenge. On failure, the buffer is broken.
750 extern int c_check(buf */
*b*/
);
752 /*----- Administration interface ------------------------------------------*/
754 #define A_END ((char *)0)
756 /* --- @a_warn@ --- *
758 * Arguments: @const char *fmt@ = pointer to format string
759 * @...@ = other arguments
763 * Use: Informs all admin connections of a warning.
766 extern void a_warn(const char */
*fmt*/
, ...);
768 /* --- @a_notify@ --- *
770 * Arguments: @const char *fmt@ = pointer to format string
771 * @...@ = other arguments
775 * Use: Sends a notification to interested admin connections.
778 extern void a_notify(const char */
*fmt*/
, ...);
780 /* --- @a_create@ --- *
782 * Arguments: @int fd_in, fd_out@ = file descriptors to use
783 * @unsigned f@ = initial flags to set
787 * Use: Creates a new admin connection.
790 extern void a_create(int /*fd_in*/, int /*fd_out*/, unsigned /*f*/);
792 /* --- @a_quit@ --- *
798 * Use: Shuts things down nicely.
801 extern void a_quit(void);
803 /* --- @a_preselect@ --- *
809 * Use: Informs the admin module that we're about to select again,
810 * and that it should do cleanup things it has delayed until a
814 extern void a_preselect(void);
816 /* --- @a_daemon@ --- *
822 * Use: Informs the admin module that it's a daemon.
825 extern void a_daemon(void);
827 /* --- @a_init@ --- *
829 * Arguments: @const char *sock@ = socket name to create
833 * Use: Creates the admin listening socket.
836 extern void a_init(const char */
*sock*/
);
838 /*----- Peer management ---------------------------------------------------*/
840 /* --- @p_txstart@ --- *
842 * Arguments: @peer *p@ = pointer to peer block
843 * @unsigned msg@ = message type code
845 * Returns: A pointer to a buffer to write to.
847 * Use: Starts sending to a peer. Only one send can happen at a
851 extern buf
*p_txstart(peer */
*p*/
, unsigned /*msg*/);
853 /* --- @p_txend@ --- *
855 * Arguments: @peer *p@ = pointer to peer block
859 * Use: Sends a packet to the peer.
862 extern void p_txend(peer */
*p*/
);
864 /* --- @p_pingsend@ --- *
866 * Arguments: @peer *p@ = destination peer
867 * @ping *pg@ = structure to fill in
868 * @unsigned type@ = message type
869 * @unsigned long timeout@ = how long to wait before giving up
870 * @void (*func)(int, void *)@ = callback function
871 * @void *arg@ = argument for callback
873 * Returns: Zero if successful, nonzero if it failed.
875 * Use: Sends a ping to a peer. Call @func@ with a nonzero argument
876 * if we get an answer within the timeout, or zero if no answer.
879 extern int p_pingsend(peer */
*p*/
, ping */
*pg*/
, unsigned /*type*/,
880 unsigned long /*timeout*/,
881 void (*/
*func*/
)(int, void *), void */
*arg*/
);
883 /* --- @p_pingdone@ --- *
885 * Arguments: @ping *p@ = ping structure
886 * @int rc@ = return code to pass on
890 * Use: Disposes of a ping structure, maybe sending a notification.
893 extern void p_pingdone(ping */
*p*/
, int /*rc*/);
895 /* --- @p_greet@ --- *
897 * Arguments: @peer *p@ = peer to send to
898 * @const void *c@ = pointer to challenge
899 * @size_t sz@ = size of challenge
903 * Use: Sends a greeting packet.
906 extern void p_greet(peer */
*p*/
, const void */
*c*/
, size_t /*sz*/);
910 * Arguments: @peer *p@ = pointer to peer block
911 * @buf *b@ = buffer containing incoming packet
915 * Use: Handles a packet which needs to be sent to a peer.
918 extern void p_tun(peer */
*p*/
, buf */
*b*/
);
920 /* --- @p_keyreload@ --- *
926 * Use: Forces a check of the daemon's keyring files.
929 extern void p_keyreload(void);
931 /* --- @p_interval@ --- *
937 * Use: Called periodically to do tidying.
940 extern void p_interval(void);
942 /* --- @p_stats@ --- *
944 * Arguments: @peer *p@ = pointer to a peer block
946 * Returns: A pointer to the peer's statistics.
949 extern stats
*p_stats(peer */
*p*/
);
951 /* --- @p_ifname@ --- *
953 * Arguments: @peer *p@ = pointer to a peer block
955 * Returns: A pointer to the peer's interface name.
958 extern const char *p_ifname(peer */
*p*/
);
960 /* --- @p_setifname@ --- *
962 * Arguments: @peer *p@ = pointer to a peer block
963 * @const char *name@ = pointer to the new name
967 * Use: Changes the name held for a peer's interface.
970 extern void p_setifname(peer */
*p*/
, const char */
*name*/
);
972 /* --- @p_addr@ --- *
974 * Arguments: @peer *p@ = pointer to a peer block
976 * Returns: A pointer to the peer's address.
979 extern const addr
*p_addr(peer */
*p*/
);
981 /* --- @p_init@ --- *
983 * Arguments: @struct in_addr addr@ = address to bind to
984 * @unsigned port@ = port number to listen to
988 * Use: Initializes the peer system; creates the socket.
991 extern void p_init(struct in_addr
/*addr*/, unsigned /*port*/);
993 /* --- @p_port@ --- *
997 * Returns: Port number used for socket.
1000 unsigned p_port(void);
1002 /* --- @p_create@ --- *
1004 * Arguments: @peerspec *spec@ = information about this peer
1006 * Returns: Pointer to the peer block, or null if it failed.
1008 * Use: Creates a new named peer block. No peer is actually attached
1012 extern peer
*p_create(peerspec */
*spec*/
);
1014 /* --- @p_name@ --- *
1016 * Arguments: @peer *p@ = pointer to a peer block
1018 * Returns: A pointer to the peer's name.
1020 * Use: Equivalent to @p_spec(p)->name@.
1023 extern const char *p_name(peer */
*p*/
);
1025 /* --- @p_spec@ --- *
1027 * Arguments: @peer *p@ = pointer to a peer block
1029 * Returns: Pointer to the peer's specification
1032 extern const peerspec
*p_spec(peer */
*p*/
);
1034 /* --- @p_find@ --- *
1036 * Arguments: @const char *name@ = name to look up
1038 * Returns: Pointer to the peer block, or null if not found.
1040 * Use: Finds a peer by name.
1043 extern peer
*p_find(const char */
*name*/
);
1045 /* --- @p_destroy@ --- *
1047 * Arguments: @peer *p@ = pointer to a peer
1051 * Use: Destroys a peer.
1054 extern void p_destroy(peer */
*p*/
);
1056 /* --- @p_first@, @p_next@ --- *
1058 * Arguments: @peer *p@ = a peer block
1060 * Returns: @peer_first@ returns the first peer in some ordering;
1061 * @peer_next@ returns the peer following a given one in the
1062 * same ordering. Null is returned for the end of the list.
1065 extern peer
*p_first(void);
1066 extern peer
*p_next(peer */
*p*/
);
1068 /*----- Tunnel drivers ----------------------------------------------------*/
1071 extern const tunnel_ops tun_linux
;
1075 extern const tunnel_ops tun_unet
;
1079 extern const tunnel_ops tun_bsd
;
1082 extern const tunnel_ops tun_slip
;
1084 /*----- Other handy utilities ---------------------------------------------*/
1086 /* --- @mpstr@ --- *
1088 * Arguments: @mp *m@ = a multiprecision integer
1090 * Returns: A pointer to the integer's textual representation.
1092 * Use: Converts a multiprecision integer to a string. Corrupts
1096 extern const char *mpstr(mp */
*m*/
);
1098 /* --- @gestr@ --- *
1100 * Arguments: @group *g@ = a group
1101 * @ge *x@ = a group element
1103 * Returns: A pointer to the element's textual representation.
1105 * Use: Converts a group element to a string. Corrupts
1109 extern const char *gestr(group */
*g*/
, ge */
*x*/
);
1111 /* --- @timestr@ --- *
1113 * Arguments: @time_t t@ = a time to convert
1115 * Returns: A pointer to a textual representation of the time.
1117 * Use: Converts a time to a textual representation. Corrupts
1121 extern const char *timestr(time_t /*t*/);
1123 /* --- @mystrieq@ --- *
1125 * Arguments: @const char *x, *y@ = two strings
1127 * Returns: True if @x@ and @y are equal, up to case.
1130 extern int mystrieq(const char */
*x*/
, const char */
*y*/
);
1132 /* --- @seq_reset@ --- *
1134 * Arguments: @seqwin *s@ = sequence-checking window
1138 * Use: Resets a sequence number window.
1141 extern void seq_reset(seqwin */
*s*/
);
1143 /* --- @seq_check@ --- *
1145 * Arguments: @seqwin *s@ = sequence-checking window
1146 * @uint32 q@ = sequence number to check
1147 * @const char *service@ = service to report message from
1149 * Returns: A @SEQ_@ code.
1151 * Use: Checks a sequence number against the window, updating things
1155 extern int seq_check(seqwin */
*s*/
, uint32
/*q*/, const char */
*service*/
);
1157 /* --- @versioncmp@ --- *
1159 * Arguments: @const char *va, *vb@ = two version strings
1161 * Returns: Less than, equal to, or greater than zero, according to
1162 * whether @va@ is less than, equal to, or greater than @vb@.
1164 * Use: Compares version number strings.
1166 * The algorithm is an extension of the Debian version
1167 * comparison algorithm. A version number consists of three
1170 * [EPOCH :] MAIN [- SUB]
1172 * The MAIN part may contain colons or hyphens if there is an
1173 * EPOCH or SUB, respectively. Version strings are compared
1174 * componentwise: first epochs, then main parts, and finally
1177 * The component comparison is done as follows. First, the
1178 * initial subsequence of nondigit characters is extracted from
1179 * each string, and these are compared lexicographically, using
1180 * ASCII ordering, except that letters precede non-letters. If
1181 * both are the same, an initial sequence of digits is extracted
1182 * from the remaining parts of the version strings, and these
1183 * are compared numerically (an empty sequence being considered
1184 * to have the value zero). This process is repeated until we
1185 * have a winner or until both strings are exhausted.
1188 extern int versioncmp(const char */
*va*/
, const char */
*vb*/
);
1190 /*----- That's all, folks -------------------------------------------------*/