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
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * TrIPE is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with TrIPE; if not, write to the Free Software Foundation,
24 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
34 /*----- Header files ------------------------------------------------------*/
50 #include <sys/types.h>
57 #include <sys/socket.h>
59 #include <netinet/in.h>
60 #include <arpa/inet.h>
66 #include <mLib/alloc.h>
67 #include <mLib/arena.h>
68 #include <mLib/base64.h>
69 #include <mLib/bres.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>
93 #include <catacomb/gcipher.h>
94 #include <catacomb/gmac.h>
95 #include <catacomb/grand.h>
96 #include <catacomb/key.h>
97 #include <catacomb/paranoia.h>
99 #include <catacomb/noise.h>
100 #include <catacomb/rand.h>
102 #include <catacomb/mp.h>
103 #include <catacomb/mprand.h>
104 #include <catacomb/dh.h>
105 #include <catacomb/ec.h>
106 #include <catacomb/ec-keys.h>
107 #include <catacomb/group.h>
110 #include "protocol.h"
116 /*----- Magic numbers -----------------------------------------------------*/
118 /* --- Trace flags --- */
126 #define T_KEYEXCH 64u
127 #define T_KEYMGMT 128u
129 /* T_PRIVSEP in priv.h */
135 #define SEC(n) (n##u)
136 #define MIN(n) (n##u * 60u)
137 #define MEG(n) (n##ul * 1024ul * 1024ul)
139 /* --- Timing parameters --- */
141 #define T_EXP MIN(60) /* Expiry time for a key */
142 #define T_REGEN MIN(40) /* Regeneration time for a key */
144 #define T_VALID SEC(20) /* Challenge validity period */
145 #define T_RETRY SEC(10) /* Challenge retransmit interval */
147 /* --- Other things --- */
149 #define PKBUFSZ 65536
151 /*----- Cipher selections -------------------------------------------------*/
153 typedef struct algswitch {
154 const gccipher *c; /* Symmetric encryption scheme */
155 const gccipher *mgf; /* Mask-generation function */
156 const gchash *h; /* Hash function */
157 const gcmac *m; /* Message authentication code */
158 size_t hashsz; /* Hash output size */
159 size_t tagsz; /* Length to truncate MAC tags */
160 size_t expsz; /* Size of data to process */
161 size_t cksz, mksz; /* Key lengths for @c@ and @m@ */
164 extern algswitch algs;
166 #define MAXHASHSZ 64 /* Largest possible hash size */
168 #define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
170 /*----- Data structures ---------------------------------------------------*/
172 /* --- Socket addresses --- *
174 * A magic union of supported socket addresses.
179 struct sockaddr_in sin;
182 /* --- Mapping keyed on addresses --- */
184 typedef struct addrmap {
189 typedef struct addrmap_base {
194 /* --- Sequence number checking --- */
196 typedef struct seqwin {
197 uint32 seq; /* First acceptable input sequence */
198 uint32 win; /* Window of acceptable numbers */
201 #define SEQ_WINSZ 32 /* Bits in sequence number window */
203 /* --- A symmetric keyset --- *
205 * A keyset contains a set of symmetric keys for encrypting and decrypting
206 * packets. Keysets are stored in a list, sorted in reverse order of
207 * creation, so that the most recent keyset (the one most likely to be used)
210 * Each keyset has a time limit and a data limit. The keyset is destroyed
211 * when either it has existed for too long, or it has been used to encrypt
212 * too much data. New key exchanges are triggered when keys are close to
216 typedef struct keyset {
217 struct keyset *next; /* Next active keyset in the list */
218 unsigned ref; /* Reference count for keyset */
219 struct peer *p; /* Pointer to peer structure */
220 time_t t_exp; /* Expiry time for this keyset */
221 unsigned long sz_exp, sz_regen; /* Data limits for the keyset */
222 T( unsigned seq; ) /* Sequence number for tracing */
223 unsigned f; /* Various useful flags */
224 gcipher *cin, *cout; /* Keyset ciphers for encryption */
225 size_t tagsz; /* Length to truncate MAC tags */
226 gmac *min, *mout; /* Keyset MACs for integrity */
227 uint32 oseq; /* Outbound sequence number */
228 seqwin iseq; /* Inbound sequence number */
231 #define KSF_LISTEN 1u /* Don't encrypt packets yet */
232 #define KSF_LINK 2u /* Key is in a linked list */
234 #define KSERR_REGEN -1 /* Regenerate keys */
235 #define KSERR_NOKEYS -2 /* No keys left */
236 #define KSERR_DECRYPT -3 /* Unable to decrypt message */
237 #define KSERR_SEQ -4 /* Incorrect sequence number */
238 #define KSERR_MALFORMED -5 /* Input ciphertext is broken */
240 /* --- Key exchange --- *
242 * TrIPE uses the Wrestlers Protocol for its key exchange. The Wrestlers
243 * Protocol has a number of desirable features (e.g., perfect forward
244 * secrecy, and zero-knowledge authentication) which make it attractive for
245 * use in TrIPE. The Wrestlers Protocol was designed by Mark Wooding and
251 typedef struct kxchal {
252 struct keyexch *kx; /* Pointer back to key exchange */
253 ge *c; /* Responder's challenge */
254 ge *r; /* My reply to the challenge */
255 keyset *ks; /* Pointer to temporary keyset */
256 unsigned f; /* Various useful flags */
257 sel_timer t; /* Response timer for challenge */
258 octet hc[MAXHASHSZ]; /* Hash of his challenge */
259 octet ck[MAXHASHSZ]; /* His magical check value */
260 octet hswrq_in[MAXHASHSZ]; /* Inbound switch request message */
261 octet hswok_in[MAXHASHSZ]; /* Inbound switch confirmation */
262 octet hswrq_out[MAXHASHSZ]; /* Outbound switch request message */
263 octet hswok_out[MAXHASHSZ]; /* Outbound switch confirmation */
266 typedef struct keyexch {
267 struct peer *p; /* Pointer back to the peer */
268 keyset **ks; /* Peer's list of keysets */
269 unsigned f; /* Various useful flags */
270 unsigned s; /* Current state in exchange */
271 sel_timer t; /* Timer for next exchange */
272 ge *kpub; /* Peer's public key */
273 time_t texp_kpub; /* Expiry time for public key */
274 mp *alpha; /* My temporary secret */
275 ge *c; /* My challenge */
276 ge *rx; /* The expected response */
277 unsigned nr; /* Number of extant responses */
278 time_t t_valid; /* When this exchange goes bad */
279 octet hc[MAXHASHSZ]; /* Hash of my challenge */
280 kxchal *r[KX_NCHAL]; /* Array of challenges */
283 #define KXF_TIMER 1u /* Waiting for a timer to go off */
284 #define KXF_DEAD 2u /* The key-exchanger isn't up */
285 #define KXF_PUBKEY 4u /* Key exchanger has a public key */
286 #define KXF_CORK 8u /* Don't send anything yet */
289 KXS_DEAD, /* Uninitialized state (magical) */
290 KXS_CHAL, /* Main answer-challenges state */
291 KXS_COMMIT, /* Committed: send switch request */
292 KXS_SWITCH /* Switched: send confirmation */
295 /* --- Tunnel structure --- *
297 * Used to maintain system-specific information about the tunnel interface.
300 typedef struct tunnel tunnel;
303 typedef struct tunnel_ops {
304 const char *name; /* Name of this tunnel driver */
305 unsigned flags; /* Various interesting flags */
306 #define TUNF_PRIVOPEN 1u /* Need helper to open file */
307 void (*init)(void); /* Initializes the system */
308 tunnel *(*create)(struct peer */*p*/, int /*fd*/, char **/*ifn*/);
309 /* Initializes a new tunnel */
310 void (*setifname)(tunnel */*t*/, const char */*ifn*/);
311 /* Notifies ifname change */
312 void (*inject)(tunnel */*t*/, buf */*b*/); /* Sends packet through if */
313 void (*destroy)(tunnel */*t*/); /* Destroys a tunnel */
316 #ifndef TUN_INTERNALS
317 struct tunnel { const tunnel_ops *ops; };
320 /* --- Peer statistics --- *
322 * Contains various interesting and not-so-interesting statistics about a
323 * peer. This is updated by various parts of the code. The format of the
324 * structure isn't considered private, and @p_stats@ returns a pointer to the
325 * statistics block for a given peer.
328 typedef struct stats {
329 unsigned long sz_in, sz_out; /* Size of all data in and out */
330 unsigned long sz_kxin, sz_kxout; /* Size of key exchange messages */
331 unsigned long sz_ipin, sz_ipout; /* Size of encapsulated IP packets */
332 time_t t_start, t_last, t_kx; /* Time peer created, last pk, kx */
333 unsigned long n_reject; /* Number of rejected packets */
334 unsigned long n_in, n_out; /* Number of packets in and out */
335 unsigned long n_kxin, n_kxout; /* Number of key exchange packets */
336 unsigned long n_ipin, n_ipout; /* Number of encrypted packets */
339 /* --- Peer structure --- *
341 * The main structure which glues everything else together.
344 typedef struct peerspec {
345 char *name; /* Peer's name */
346 char *tag; /* Public key tag */
347 const tunnel_ops *tops; /* Tunnel operations */
348 unsigned long t_ka; /* Keep alive interval */
349 addr sa; /* Socket address to speak to */
350 size_t sasz; /* Socket address size */
351 unsigned f; /* Flags for the peer */
352 #define PSF_KXMASK 255u /* Key-exchange flags to set */
353 #define PSF_MOBILE 256u /* Address may change rapidly */
356 typedef struct peer_byname {
361 typedef struct peer_byaddr {
366 typedef struct peer {
367 peer_byname *byname; /* Lookup-by-name block */
368 peer_byaddr *byaddr; /* Lookup-by-address block */
369 struct ping *pings; /* Pings we're waiting for */
370 peerspec spec; /* Specifications for this peer */
371 tunnel *t; /* Tunnel for local packets */
372 char *ifname; /* Interface name for tunnel */
373 keyset *ks; /* List head for keysets */
374 buf b; /* Buffer for sending packets */
375 stats st; /* Statistics */
376 keyexch kx; /* Key exchange protocol block */
377 sel_timer tka; /* Timer for keepalives */
380 typedef struct peer_iter { sym_iter i; } peer_iter;
382 typedef struct ping {
383 struct ping *next, *prev; /* Links to next and previous */
384 peer *p; /* Peer so we can free it */
385 unsigned msg; /* Kind of response expected */
386 uint32 id; /* Id so we can recognize response */
387 octet magic[32]; /* Some random data */
388 sel_timer t; /* Timeout for ping */
389 void (*func)(int /*rc*/, void */*arg*/); /* Function to call when done */
390 void *arg; /* Argument for callback */
401 /* --- Admin structure --- */
403 #define OBUFSZ 16384u
405 typedef struct obuf {
406 struct obuf *next; /* Next buffer in list */
407 char *p_in, *p_out; /* Pointers into the buffer */
408 char buf[OBUFSZ]; /* The actual buffer */
411 typedef struct oqueue {
412 obuf *hd, *tl; /* Head and tail pointers */
417 typedef struct admin_bgop {
418 struct admin_bgop *next, *prev; /* Links to next and previous */
419 struct admin *a; /* Owner job */
420 char *tag; /* Tag string for messages */
421 void (*cancel)(struct admin_bgop *); /* Destructor function */
424 typedef struct admin_resop {
425 admin_bgop bg; /* Background operation header */
426 char *addr; /* Hostname to be resolved */
427 bres_client r; /* Background resolver task */
428 sel_timer t; /* Timer for resolver */
429 addr sa; /* Socket address */
430 size_t sasz; /* Socket address size */
431 void (*func)(struct admin_resop *, int); /* Handler */
434 enum { ARES_OK, ARES_FAIL };
436 typedef struct admin_addop {
437 admin_resop r; /* Name resolution header */
438 peerspec peer; /* Peer pending creation */
441 typedef struct admin_pingop {
442 admin_bgop bg; /* Background operation header */
443 ping ping; /* Ping pending response */
444 struct timeval pingtime; /* Time last ping was sent */
447 typedef struct admin_service {
448 sym_base _b; /* Hash table base structure */
449 char *version; /* The provided version */
450 struct admin *prov; /* Which client provides me */
451 struct admin_service *next, *prev; /* Client's list of services */
454 typedef struct admin_svcop {
455 admin_bgop bg; /* Background operation header */
456 struct admin *prov; /* Client servicing this job */
457 unsigned index; /* This job's index */
458 struct admin_svcop *next, *prev; /* Links for provider's jobs */
461 typedef struct admin_jobentry {
462 unsigned short seq; /* Zero if unused */
464 admin_svcop *op; /* Operation, if slot in use, ... */
465 uint32 next; /* ... or index of next free slot */
469 typedef struct admin_jobtable {
470 uint32 n, sz; /* Used slots and table size */
471 admin_svcop *active; /* List of active jobs */
472 uint32 free; /* Index of first free slot */
473 admin_jobentry *v; /* And the big array of entries */
476 typedef struct admin {
477 struct admin *next, *prev; /* Links to next and previous */
478 unsigned f; /* Various useful flags */
479 unsigned ref; /* Reference counter */
481 unsigned seq; /* Sequence number for tracing */
483 oqueue out; /* Output buffer list */
484 oqueue delay; /* Delayed output buffer list */
485 admin_bgop *bg; /* Backgrounded operations */
486 admin_service *svcs; /* Which services I provide */
487 admin_jobtable j; /* Table of outstanding jobs */
488 selbuf b; /* Line buffer for commands */
489 sel_file w; /* Selector for write buffering */
492 #define AF_DEAD 1u /* Destroy this admin block */
493 #define AF_CLOSE 2u /* Client closed connection */
494 #define AF_NOTE 4u /* Catch notifications */
495 #define AF_WARN 8u /* Catch warning messages */
497 #define AF_TRACE 16u /* Catch tracing */
499 #define AF_FOREGROUND 32u /* Quit server when client closes */
502 # define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN)
504 # define AF_ALLMSGS (AF_NOTE | AF_WARN)
507 /*----- Global variables --------------------------------------------------*/
509 extern sel_state sel; /* Global I/O event state */
510 extern group *gg; /* The group we work in */
511 extern size_t indexsz; /* Size of exponent for the group */
512 extern mp *kpriv; /* Our private key */
513 extern ge *kpub; /* Our public key */
514 extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ], buf_u[PKBUFSZ];
515 extern const tunnel_ops *tunnels[]; /* Table of tunnels (0-term) */
516 extern const tunnel_ops *tun_default; /* Default tunnel to use */
519 extern const trace_opt tr_opts[]; /* Trace options array */
520 extern unsigned tr_flags; /* Trace options flags */
523 /*----- Other macros ------------------------------------------------------*/
525 #define TIMER noise_timer(RAND_GLOBAL)
527 /*----- Key management ----------------------------------------------------*/
529 /* --- @km_reload@ --- *
533 * Returns: Zero if OK, nonzero to force reloading of keys.
535 * Use: Checks the keyrings to see if they need reloading.
538 extern int km_reload(void);
540 /* --- @km_init@ --- *
542 * Arguments: @const char *kr_priv@ = private keyring file
543 * @const char *kr_pub@ = public keyring file
544 * @const char *tag@ = tag to load
548 * Use: Initializes, and loads the private key.
551 extern void km_init(const char */*kr_priv*/, const char */*kr_pub*/,
552 const char */*tag*/);
554 /* --- @km_getpubkey@ --- *
556 * Arguments: @const char *tag@ = public key tag to load
557 * @ge *kpub@ = where to put the public key
558 * @time_t *t_exp@ = where to put the expiry time
560 * Returns: Zero if OK, nonzero if it failed.
562 * Use: Fetches a public key from the keyring.
565 extern int km_getpubkey(const char */*tag*/, ge */*kpub*/,
568 /*----- Key exchange ------------------------------------------------------*/
570 /* --- @kx_start@ --- *
572 * Arguments: @keyexch *kx@ = pointer to key exchange context
573 * @int forcep@ = nonzero to ignore the quiet timer
577 * Use: Stimulates a key exchange. If a key exchage is in progress,
578 * a new challenge is sent (unless the quiet timer forbids
579 * this); if no exchange is in progress, one is commenced.
582 extern void kx_start(keyexch */*kx*/, int /*forcep*/);
584 /* --- @kx_message@ --- *
586 * Arguments: @keyexch *kx@ = pointer to key exchange context
587 * @unsigned msg@ = the message code
588 * @buf *b@ = pointer to buffer containing the packet
592 * Use: Reads a packet containing key exchange messages and handles
596 extern void kx_message(keyexch */*kx*/, unsigned /*msg*/, buf */*b*/);
598 /* --- @kx_free@ --- *
600 * Arguments: @keyexch *kx@ = pointer to key exchange context
604 * Use: Frees everything in a key exchange context.
607 extern void kx_free(keyexch */*kx*/);
609 /* --- @kx_newkeys@ --- *
611 * Arguments: @keyexch *kx@ = pointer to key exchange context
615 * Use: Informs the key exchange module that its keys may have
616 * changed. If fetching the new keys fails, the peer will be
617 * destroyed, we log messages and struggle along with the old
621 extern void kx_newkeys(keyexch */*kx*/);
623 /* --- @kx_init@ --- *
625 * Arguments: @keyexch *kx@ = pointer to key exchange context
626 * @peer *p@ = pointer to peer context
627 * @keyset **ks@ = pointer to keyset list
628 * @unsigned f@ = various useful flags
630 * Returns: Zero if OK, nonzero if it failed.
632 * Use: Initializes a key exchange module. The module currently
633 * contains no keys, and will attempt to initiate a key
637 extern int kx_init(keyexch */*kx*/, peer */*p*/,
638 keyset **/*ks*/, unsigned /*f*/);
640 /*----- Keysets and symmetric cryptography --------------------------------*/
642 /* --- @ks_drop@ --- *
644 * Arguments: @keyset *ks@ = pointer to a keyset
648 * Use: Decrements a keyset's reference counter. If the counter hits
649 * zero, the keyset is freed.
652 extern void ks_drop(keyset */*ks*/);
654 /* --- @ks_gen@ --- *
656 * Arguments: @const void *k@ = pointer to key material
657 * @size_t x, y, z@ = offsets into key material (see below)
658 * @peer *p@ = pointer to peer information
660 * Returns: A pointer to the new keyset.
662 * Use: Derives a new keyset from the given key material. The
663 * offsets @x@, @y@ and @z@ separate the key material into three
664 * parts. Between the @k@ and @k + x@ is `my' contribution to
665 * the key material; between @k + x@ and @k + y@ is `your'
666 * contribution; and between @k + y@ and @k + z@ is a shared
667 * value we made together. These are used to construct two
668 * pairs of symmetric keys. Each pair consists of an encryption
669 * key and a message authentication key. One pair is used for
670 * outgoing messages, the other for incoming messages.
672 * The new key is marked so that it won't be selected for output
673 * by @ksl_encrypt@. You can still encrypt data with it by
674 * calling @ks_encrypt@ directly.
677 extern keyset *ks_gen(const void */*k*/,
678 size_t /*x*/, size_t /*y*/, size_t /*z*/,
681 /* --- @ks_activate@ --- *
683 * Arguments: @keyset *ks@ = pointer to a keyset
687 * Use: Activates a keyset, so that it can be used for encrypting
691 extern void ks_activate(keyset */*ks*/);
693 /* --- @ks_encrypt@ --- *
695 * Arguments: @keyset *ks@ = pointer to a keyset
696 * @unsigned ty@ = message type
697 * @buf *b@ = pointer to input buffer
698 * @buf *bb@ = pointer to output buffer
700 * Returns: Zero if successful; @KSERR_REGEN@ if we should negotiate a
701 * new key; @KSERR_NOKEYS@ if the key is not usable. Also
702 * returns zero if there was insufficient buffer (but the output
703 * buffer is broken in this case).
705 * Use: Encrypts a block of data using the key. Note that the `key
706 * ought to be replaced' notification is only ever given once
707 * for each key. Also note that this call forces a keyset to be
708 * used even if it's marked as not for data output.
711 extern int ks_encrypt(keyset */*ks*/, unsigned /*ty*/,
712 buf */*b*/, buf */*bb*/);
714 /* --- @ks_decrypt@ --- *
716 * Arguments: @keyset *ks@ = pointer to a keyset
717 * @unsigned ty@ = expected type code
718 * @buf *b@ = pointer to an input buffer
719 * @buf *bb@ = pointer to an output buffer
721 * Returns: Zero on success; @KSERR_DECRYPT@ on failure. Also returns
722 * zero if there was insufficient buffer (but the output buffer
723 * is broken in this case).
725 * Use: Attempts to decrypt a message using a given key. Note that
726 * requesting decryption with a key directly won't clear a
727 * marking that it's not for encryption.
730 extern int ks_decrypt(keyset */*ks*/, unsigned /*ty*/,
731 buf */*b*/, buf */*bb*/);
733 /* --- @ksl_free@ --- *
735 * Arguments: @keyset **ksroot@ = pointer to keyset list head
739 * Use: Frees (releases references to) all of the keys in a keyset.
742 extern void ksl_free(keyset **/*ksroot*/);
744 /* --- @ksl_link@ --- *
746 * Arguments: @keyset **ksroot@ = pointer to keyset list head
747 * @keyset *ks@ = pointer to a keyset
751 * Use: Links a keyset into a list. A keyset can only be on one list
752 * at a time. Bad things happen otherwise.
755 extern void ksl_link(keyset **/*ksroot*/, keyset */*ks*/);
757 /* --- @ksl_prune@ --- *
759 * Arguments: @keyset **ksroot@ = pointer to keyset list head
763 * Use: Prunes the keyset list by removing keys which mustn't be used
767 extern void ksl_prune(keyset **/*ksroot*/);
769 /* --- @ksl_encrypt@ --- *
771 * Arguments: @keyset **ksroot@ = pointer to keyset list head
772 * @unsigned ty@ = message type
773 * @buf *b@ = pointer to input buffer
774 * @buf *bb@ = pointer to output buffer
776 * Returns: Zero if successful; @KSERR_REGEN@ if it's time to negotiate a
777 * new key; @KSERR_NOKEYS@ if there are no suitable keys
778 * available. Also returns zero if there was insufficient
779 * buffer space (but the output buffer is broken in this case).
781 * Use: Encrypts a packet.
784 extern int ksl_encrypt(keyset **/*ksroot*/, unsigned /*ty*/,
785 buf */*b*/, buf */*bb*/);
787 /* --- @ksl_decrypt@ --- *
789 * Arguments: @keyset **ksroot@ = pointer to keyset list head
790 * @unsigned ty@ = expected type code
791 * @buf *b@ = pointer to input buffer
792 * @buf *bb@ = pointer to output buffer
794 * Returns: Zero on success; @KSERR_DECRYPT@ on failure. Also returns
795 * zero if there was insufficient buffer (but the output buffer
796 * is broken in this case).
798 * Use: Decrypts a packet.
801 extern int ksl_decrypt(keyset **/*ksroot*/, unsigned /*ty*/,
802 buf */*b*/, buf */*bb*/);
804 /*----- Challenges --------------------------------------------------------*/
808 * Arguments: @buf *b@ = where to put the challenge
810 * Returns: Zero if OK, nonzero on error.
812 * Use: Issues a new challenge.
815 extern int c_new(buf */*b*/);
817 /* --- @c_check@ --- *
819 * Arguments: @buf *b@ = where to find the challenge
821 * Returns: Zero if OK, nonzero if it didn't work.
823 * Use: Checks a challenge. On failure, the buffer is broken.
826 extern int c_check(buf */*b*/);
828 /*----- Administration interface ------------------------------------------*/
830 #define A_END ((char *)0)
832 /* --- @a_vformat@ --- *
834 * Arguments: @dstr *d@ = where to leave the formatted message
835 * @const char *fmt@ = pointer to format string
836 * @va_list ap@ = arguments in list
840 * Use: Main message token formatting driver. The arguments are
841 * interleaved formatting tokens and their parameters, finally
842 * terminated by an entry @A_END@.
846 * * "*..." ... -- pretokenized @dstr_putf@-like string
848 * * "?ADDR" SOCKADDR -- a socket address, to be converted
850 * * "?B64" BUFFER SIZE -- binary data to be base64-encoded
852 * * "?TOKENS" VECTOR -- null-terminated vector of tokens
854 * * "?PEER" PEER -- peer's name
856 * * "?ERRNO" ERRNO -- system error code
858 * * "[!]..." ... -- @dstr_putf@-like string as single token
861 extern void a_vformat(dstr */*d*/, const char */*fmt*/, va_list /*ap*/);
863 /* --- @a_warn@ --- *
865 * Arguments: @const char *fmt@ = pointer to format string
866 * @...@ = other arguments
870 * Use: Informs all admin connections of a warning.
873 extern void a_warn(const char */*fmt*/, ...);
875 /* --- @a_notify@ --- *
877 * Arguments: @const char *fmt@ = pointer to format string
878 * @...@ = other arguments
882 * Use: Sends a notification to interested admin connections.
885 extern void a_notify(const char */*fmt*/, ...);
887 /* --- @a_create@ --- *
889 * Arguments: @int fd_in, fd_out@ = file descriptors to use
890 * @unsigned f@ = initial flags to set
894 * Use: Creates a new admin connection.
897 extern void a_create(int /*fd_in*/, int /*fd_out*/, unsigned /*f*/);
899 /* --- @a_quit@ --- *
905 * Use: Shuts things down nicely.
908 extern void a_quit(void);
910 /* --- @a_preselect@ --- *
916 * Use: Informs the admin module that we're about to select again,
917 * and that it should do cleanup things it has delayed until a
921 extern void a_preselect(void);
923 /* --- @a_daemon@ --- *
929 * Use: Informs the admin module that it's a daemon.
932 extern void a_daemon(void);
934 /* --- @a_init@ --- *
936 * Arguments: @const char *sock@ = socket name to create
937 * @uid_t u@ = user to own the socket
938 * @gid_t g@ = group to own the socket
939 * @mode_t m@ = permissions to set on the socket
943 * Use: Creates the admin listening socket.
946 extern void a_init(const char */*sock*/,
947 uid_t /*u*/, gid_t /*g*/, mode_t /*m*/);
949 /*----- Mapping with addresses as keys ------------------------------------*/
951 /* --- @am_create@ --- *
953 * Arguments: @addrmap *m@ = pointer to map
957 * Use: Create an address map, properly set up.
960 extern void am_create(addrmap */*m*/);
962 /* --- @am_destroy@ --- *
964 * Arguments: @addrmap *m@ = pointer to map
968 * Use: Destroy an address map, throwing away all the entries.
971 extern void am_destroy(addrmap */*m*/);
973 /* --- @am_find@ --- *
975 * Arguments: @addrmap *m@ = pointer to map
976 * @const addr *a@ = address to look up
977 * @size_t sz@ = size of block to allocate
978 * @unsigned *f@ = where to store flags
980 * Returns: Pointer to found item, or null.
982 * Use: Finds a record with the given IP address, set @*f@ nonzero
983 * and returns it. If @sz@ is zero, and no match was found,
984 * return null; otherwise allocate a new block of @sz@ bytes,
985 * clear @*f@ to zero and return the block pointer.
988 extern void *am_find(addrmap */*m*/, const addr */*a*/,
989 size_t /*sz*/, unsigned */*f*/);
991 /* --- @am_remove@ --- *
993 * Arguments: @addrmap *m@ = pointer to map
994 * @void *i@ = pointer to the item
998 * Use: Removes an item from the map.
1001 extern void am_remove(addrmap */*m*/, void */*i*/);
1003 /*----- Privilege separation ----------------------------------------------*/
1005 /* --- @ps_trace@ --- *
1007 * Arguments: @unsigned mask@ = trace mask to check
1008 * @const char *fmt@ = message format
1009 * @...@ = values for placeholders
1013 * Use: Writes a trace message.
1016 T( extern void ps_trace(unsigned /*mask*/, const char */*fmt*/, ...); )
1018 /* --- @ps_warn@ --- *
1020 * Arguments: @const char *fmt@ = message format
1021 * @...@ = values for placeholders
1025 * Use: Writes a warning message.
1028 extern void ps_warn(const char */*fmt*/, ...);
1030 /* --- @ps_tunfd@ --- *
1032 * Arguments: @const tunnel_ops *tops@ = pointer to tunnel operations
1033 * @char **ifn@ = where to put the interface name
1035 * Returns: The file descriptor, or @-1@ on error.
1037 * Use: Fetches a file descriptor for a tunnel driver.
1040 extern int ps_tunfd(const tunnel_ops */*tops*/, char **/*ifn*/);
1042 /* --- @ps_split@ --- *
1044 * Arguments: @int detachp@ = whether to detach the child from its terminal
1048 * Use: Separates off the privileged tunnel-opening service from the
1049 * rest of the server.
1052 extern void ps_split(int /*detachp*/);
1054 /* --- @ps_quit@ --- *
1060 * Use: Detaches from the helper process.
1063 extern void ps_quit(void);
1065 /*----- Peer management ---------------------------------------------------*/
1067 /* --- @p_txstart@ --- *
1069 * Arguments: @peer *p@ = pointer to peer block
1070 * @unsigned msg@ = message type code
1072 * Returns: A pointer to a buffer to write to.
1074 * Use: Starts sending to a peer. Only one send can happen at a
1078 extern buf *p_txstart(peer */*p*/, unsigned /*msg*/);
1080 /* --- @p_txend@ --- *
1082 * Arguments: @peer *p@ = pointer to peer block
1086 * Use: Sends a packet to the peer.
1089 extern void p_txend(peer */*p*/);
1091 /* --- @p_pingsend@ --- *
1093 * Arguments: @peer *p@ = destination peer
1094 * @ping *pg@ = structure to fill in
1095 * @unsigned type@ = message type
1096 * @unsigned long timeout@ = how long to wait before giving up
1097 * @void (*func)(int, void *)@ = callback function
1098 * @void *arg@ = argument for callback
1100 * Returns: Zero if successful, nonzero if it failed.
1102 * Use: Sends a ping to a peer. Call @func@ with a nonzero argument
1103 * if we get an answer within the timeout, or zero if no answer.
1106 extern int p_pingsend(peer */*p*/, ping */*pg*/, unsigned /*type*/,
1107 unsigned long /*timeout*/,
1108 void (*/*func*/)(int, void *), void */*arg*/);
1110 /* --- @p_pingdone@ --- *
1112 * Arguments: @ping *p@ = ping structure
1113 * @int rc@ = return code to pass on
1117 * Use: Disposes of a ping structure, maybe sending a notification.
1120 extern void p_pingdone(ping */*p*/, int /*rc*/);
1122 /* --- @p_greet@ --- *
1124 * Arguments: @peer *p@ = peer to send to
1125 * @const void *c@ = pointer to challenge
1126 * @size_t sz@ = size of challenge
1130 * Use: Sends a greeting packet.
1133 extern void p_greet(peer */*p*/, const void */*c*/, size_t /*sz*/);
1135 /* --- @p_tun@ --- *
1137 * Arguments: @peer *p@ = pointer to peer block
1138 * @buf *b@ = buffer containing incoming packet
1142 * Use: Handles a packet which needs to be sent to a peer.
1145 extern void p_tun(peer */*p*/, buf */*b*/);
1147 /* --- @p_keyreload@ --- *
1153 * Use: Forces a check of the daemon's keyring files.
1156 extern void p_keyreload(void);
1158 /* --- @p_interval@ --- *
1164 * Use: Called periodically to do tidying.
1167 extern void p_interval(void);
1169 /* --- @p_stats@ --- *
1171 * Arguments: @peer *p@ = pointer to a peer block
1173 * Returns: A pointer to the peer's statistics.
1176 extern stats *p_stats(peer */*p*/);
1178 /* --- @p_ifname@ --- *
1180 * Arguments: @peer *p@ = pointer to a peer block
1182 * Returns: A pointer to the peer's interface name.
1185 extern const char *p_ifname(peer */*p*/);
1187 /* --- @p_setifname@ --- *
1189 * Arguments: @peer *p@ = pointer to a peer block
1190 * @const char *name@ = pointer to the new name
1194 * Use: Changes the name held for a peer's interface.
1197 extern void p_setifname(peer */*p*/, const char */*name*/);
1199 /* --- @p_addr@ --- *
1201 * Arguments: @peer *p@ = pointer to a peer block
1203 * Returns: A pointer to the peer's address.
1206 extern const addr *p_addr(peer */*p*/);
1208 /* --- @p_init@ --- *
1210 * Arguments: @struct in_addr addr@ = address to bind to
1211 * @unsigned port@ = port number to listen to
1215 * Use: Initializes the peer system; creates the socket.
1218 extern void p_init(struct in_addr /*addr*/, unsigned /*port*/);
1220 /* --- @p_port@ --- *
1224 * Returns: Port number used for socket.
1227 unsigned p_port(void);
1229 /* --- @p_create@ --- *
1231 * Arguments: @peerspec *spec@ = information about this peer
1233 * Returns: Pointer to the peer block, or null if it failed.
1235 * Use: Creates a new named peer block. No peer is actually attached
1239 extern peer *p_create(peerspec */*spec*/);
1241 /* --- @p_name@ --- *
1243 * Arguments: @peer *p@ = pointer to a peer block
1245 * Returns: A pointer to the peer's name.
1247 * Use: Equivalent to @p_spec(p)->name@.
1250 extern const char *p_name(peer */*p*/);
1252 /* --- @p_tag@ --- *
1254 * Arguments: @peer *p@ = pointer to a peer block
1256 * Returns: A pointer to the peer's public key tag.
1259 extern const char *p_tag(peer */*p*/);
1261 /* --- @p_spec@ --- *
1263 * Arguments: @peer *p@ = pointer to a peer block
1265 * Returns: Pointer to the peer's specification
1268 extern const peerspec *p_spec(peer */*p*/);
1270 /* --- @p_findbyaddr@ --- *
1272 * Arguments: @const addr *a@ = address to look up
1274 * Returns: Pointer to the peer block, or null if not found.
1276 * Use: Finds a peer by address.
1279 extern peer *p_findbyaddr(const addr */*a*/);
1281 /* --- @p_find@ --- *
1283 * Arguments: @const char *name@ = name to look up
1285 * Returns: Pointer to the peer block, or null if not found.
1287 * Use: Finds a peer by name.
1290 extern peer *p_find(const char */*name*/);
1292 /* --- @p_destroy@ --- *
1294 * Arguments: @peer *p@ = pointer to a peer
1298 * Use: Destroys a peer.
1301 extern void p_destroy(peer */*p*/);
1303 /* --- @FOREACH_PEER@ --- *
1305 * Arguments: @p@ = name to bind to each peer
1306 * @stuff@ = thing to do for each item
1308 * Use: Does something for each current peer.
1311 #define FOREACH_PEER(p, stuff) do { \
1314 for (p_mkiter(&i_); (p = p_next(&i_)) != 0; ) stuff \
1317 /* --- @p_mkiter@ --- *
1319 * Arguments: @peer_iter *i@ = pointer to an iterator
1323 * Use: Initializes the iterator.
1326 extern void p_mkiter(peer_iter */*i*/);
1328 /* --- @p_next@ --- *
1330 * Arguments: @peer_iter *i@ = pointer to an iterator
1332 * Returns: Next peer, or null if at the end.
1334 * Use: Returns the next peer.
1337 extern peer *p_next(peer_iter */*i*/);
1339 /*----- Tunnel drivers ----------------------------------------------------*/
1342 extern const tunnel_ops tun_linux;
1346 extern const tunnel_ops tun_unet;
1350 extern const tunnel_ops tun_bsd;
1353 extern const tunnel_ops tun_slip;
1355 /*----- Other handy utilities ---------------------------------------------*/
1357 /* --- @mpstr@ --- *
1359 * Arguments: @mp *m@ = a multiprecision integer
1361 * Returns: A pointer to the integer's textual representation.
1363 * Use: Converts a multiprecision integer to a string. Corrupts
1367 extern const char *mpstr(mp */*m*/);
1369 /* --- @gestr@ --- *
1371 * Arguments: @group *g@ = a group
1372 * @ge *x@ = a group element
1374 * Returns: A pointer to the element's textual representation.
1376 * Use: Converts a group element to a string. Corrupts
1380 extern const char *gestr(group */*g*/, ge */*x*/);
1382 /* --- @timestr@ --- *
1384 * Arguments: @time_t t@ = a time to convert
1386 * Returns: A pointer to a textual representation of the time.
1388 * Use: Converts a time to a textual representation. Corrupts
1392 extern const char *timestr(time_t /*t*/);
1394 /* --- @mystrieq@ --- *
1396 * Arguments: @const char *x, *y@ = two strings
1398 * Returns: True if @x@ and @y are equal, up to case.
1401 extern int mystrieq(const char */*x*/, const char */*y*/);
1403 /* --- @seq_reset@ --- *
1405 * Arguments: @seqwin *s@ = sequence-checking window
1409 * Use: Resets a sequence number window.
1412 extern void seq_reset(seqwin */*s*/);
1414 /* --- @seq_check@ --- *
1416 * Arguments: @seqwin *s@ = sequence-checking window
1417 * @uint32 q@ = sequence number to check
1418 * @const char *service@ = service to report message from
1420 * Returns: A @SEQ_@ code.
1422 * Use: Checks a sequence number against the window, updating things
1426 extern int seq_check(seqwin */*s*/, uint32 /*q*/, const char */*service*/);
1428 /*----- That's all, folks -------------------------------------------------*/