1 /* Core interface of secnet, to be used by all modules */
6 #define ADNS_FEATURE_MANYAF
18 #include <sys/types.h>
20 #include <netinet/in.h>
21 #include <arpa/inet.h>
23 #include <bsd/sys/queue.h>
25 #define MAX_PEER_ADDRS 5
26 /* send at most this many copies; honour at most that many addresses */
31 typedef char *string_t;
32 typedef const char *cstring_t;
34 #define False (_Bool)0
40 struct sockaddr_in sin;
42 struct sockaddr_in6 sin6;
46 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
47 __FILE__,__LINE__); } } while(0)
51 extern char version[];
54 extern uint32_t message_level;
55 extern bool_t secnet_is_daemon;
56 extern struct log_if *system_log;
59 extern void start_signal_handling(void);
61 /***** CONFIGURATION support *****/
63 extern bool_t just_check_config; /* If True then we're going to exit after
64 reading the configuration file */
65 extern bool_t background; /* If True then we'll eventually run as a daemon */
67 typedef struct dict dict_t; /* Configuration dictionary */
68 typedef struct closure closure_t;
69 typedef struct item item_t;
70 typedef struct list list_t; /* A list of items */
72 /* Configuration file location, for error-reporting */
78 /* Modules export closures, which can be invoked from the configuration file.
79 "Invoking" a closure usually returns another closure (of a different
80 type), but can actually return any configuration object. */
81 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
82 dict_t *context, list_t *data);
84 cstring_t description; /* For debugging */
85 uint32_t type; /* Central registry... */
87 void *interface; /* Interface for use inside secnet; depends on type */
90 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
103 /* Note that it is unwise to use this structure directly; use the list
104 manipulation functions instead. */
110 /* In the following two lookup functions, NULL means 'not found' */
111 /* Lookup a value in the specified dictionary, or its parents */
112 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
113 /* Lookup a value in just the specified dictionary */
114 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
115 /* Add a value to the specified dictionary */
116 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
117 /* Obtain an array of keys in the dictionary. malloced; caller frees */
118 extern cstring_t *dict_keys(dict_t *dict);
120 /* List-manipulation functions */
121 extern list_t *list_new(void);
122 extern int32_t list_length(const list_t *a);
123 extern list_t *list_append(list_t *a, item_t *i);
124 extern list_t *list_append_list(list_t *a, list_t *b);
125 /* Returns an item from the list (index starts at 0), or NULL */
126 extern item_t *list_elem(list_t *l, int32_t index);
128 /* Convenience functions */
129 extern list_t *new_closure(closure_t *cl);
130 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
131 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
132 bool_t fail_if_invalid, cstring_t desc,
134 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
135 cstring_t desc, struct cloc loc);
136 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
137 cstring_t desc, struct cloc loc);
138 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
139 cstring_t desc, struct cloc loc,
141 /* return value can safely be assigned to int32_t */
142 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
143 cstring_t desc, struct cloc loc, bool_t def);
144 const char **dict_read_string_array(dict_t *dict, cstring_t key,
145 bool_t required, cstring_t desc,
146 struct cloc loc, const char *const *def);
147 /* Return value is a NULL-terminated array obtained from malloc;
148 * Individual string values are still owned by config file machinery
149 * and must not be modified or freed. Returns NULL if key not
156 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
157 struct flagstr *f, cstring_t desc);
158 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
161 /***** END of configuration support *****/
163 /***** UTILITY functions *****/
165 extern char *safe_strdup(const char *string, const char *message);
166 extern void *safe_malloc(size_t size, const char *message);
167 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
168 extern void *safe_realloc_ary(void *p, size_t size, size_t count,
169 const char *message);
171 void setcloexec(int fd); /* cannot fail */
172 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
174 extern int sys_cmd(const char *file, const char *argc, ...);
176 extern uint64_t now_global;
177 extern struct timeval tv_now_global;
179 static const uint64_t *const now = &now_global;
180 static const struct timeval *const tv_now = &tv_now_global;
182 /* "now" is current program time, in milliseconds. It is derived
183 from tv_now. Both are provided by the event loop. */
185 /***** END of utility functions *****/
187 /***** START of max_start_pad handling *****/
189 extern int32_t site_max_start_pad, transform_max_start_pad,
192 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
193 int32_t calculate_max_start_pad(void);
195 /***** END of max_start_pad handling *****/
197 /***** SCHEDULING support */
199 /* If nfds_io is insufficient for your needs, set it to the required
200 number and return ERANGE. timeout is in milliseconds; if it is too
201 high then lower it. It starts at -1 (==infinite). */
202 /* Note that beforepoll_fn may NOT do anything which might change the
203 fds or timeouts wanted by other registered poll loop loopers.
204 Callers should make sure of this by not making any calls into other
205 modules from the beforepoll_fn; the easiest way to ensure this is
206 for beforepoll_fn to only retreive information and not take any
209 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
211 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
212 /* If beforepoll_fn returned ERANGE, afterpoll_fn gets nfds==0.
213 afterpoll_fn never gets !!(fds[].revents & POLLNVAL) - such
214 a report is detected as a fatal error by the event loop. */
216 /* void BEFOREPOLL_WANT_FDS(int want);
217 * Expects: int *nfds_io;
218 * Can perform non-local exit.
219 * Checks whether there is space for want fds. If so, sets *nfds_io.
220 * If not, sets *nfds_io and returns. */
221 #define BEFOREPOLL_WANT_FDS(want) do{ \
222 if (*nfds_io<(want)) { *nfds_io=(want); return ERANGE; } \
226 /* Register interest in the main loop of the program. Before a call
227 to poll() your supplied beforepoll function will be called. After
228 the call to poll() the supplied afterpoll function will be called. */
229 struct poll_interest *register_for_poll(void *st, beforepoll_fn *before,
230 afterpoll_fn *after, cstring_t desc);
231 void deregister_for_poll(struct poll_interest *i);
233 /***** END of scheduling support */
235 /***** PROGRAM LIFETIME support */
237 /* The secnet program goes through a number of phases in its lifetime.
238 Module code may arrange to be called just as various phases are
241 Remember to update the table in util.c if changing the set of
246 PHASE_GETOPTS, /* Process command-line arguments */
247 PHASE_READCONFIG, /* Parse and process configuration file */
248 PHASE_SETUP, /* Process information in configuration */
249 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
250 PHASE_GETRESOURCES, /* Obtain all external resources */
251 PHASE_DROPPRIV, /* Last chance for privileged operations */
253 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
254 /* Keep this last: */
258 typedef void hook_fn(void *self, uint32_t newphase);
259 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
260 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
262 extern uint32_t current_phase;
263 extern void enter_phase(uint32_t new_phase);
265 /* Some features (like netlink 'soft' routes) require that secnet
266 retain root privileges. They should indicate that here when
268 extern bool_t require_root_privileges;
269 extern cstring_t require_root_privileges_explanation;
271 /***** END of program lifetime support *****/
273 /***** MODULE support *****/
275 /* Module initialisation function type - modules export one function of
276 this type which is called to initialise them. For dynamically loaded
277 modules it's called "secnet_module". */
278 typedef void init_module(dict_t *dict);
280 extern void init_builtin_modules(dict_t *dict);
282 extern init_module resolver_module;
283 extern init_module random_module;
284 extern init_module udp_module;
285 extern init_module util_module;
286 extern init_module site_module;
287 extern init_module transform_eax_module;
288 extern init_module transform_cbcmac_module;
289 extern init_module netlink_module;
290 extern init_module rsa_module;
291 extern init_module dh_module;
292 extern init_module md5_module;
293 extern init_module slip_module;
294 extern init_module tun_module;
295 extern init_module sha1_module;
296 extern init_module log_module;
298 /***** END of module support *****/
300 /***** CLOSURE TYPES and interface definitions *****/
303 #define CL_RESOLVER 1
304 #define CL_RANDOMSRC 2
305 #define CL_RSAPUBKEY 3
306 #define CL_RSAPRIVKEY 4
311 #define CL_TRANSFORM 9
315 #define CL_NETLINK 14
319 /* PURE closure requires no interface */
321 /* RESOLVER interface */
323 /* Answers to queries are delivered to a function of this
324 type. 'address' will be NULL if there was a problem with the query. It
325 will be freed once resolve_answer_fn returns. naddrs is the actual
326 size of the array at addrs; was_naddrs is the number of addresses
327 actually found in the DNS, which may be bigger if addrs is equal
328 to MAX_PEER_ADDRS (ie there were too many). */
329 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
330 int naddrs, int was_naddrs,
331 const char *name, const char *failwhy);
332 /* name is the same ptr as passed to request, so its lifetime must
334 typedef bool_t resolve_request_fn(void *st, cstring_t name,
335 int remoteport, struct comm_if *comm,
336 resolve_answer_fn *cb, void *cst);
339 resolve_request_fn *request;
342 /* RANDOMSRC interface */
344 /* Return some random data. Returns TRUE for success. */
345 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
353 /* RSAPUBKEY interface */
355 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
356 cstring_t signature);
357 struct rsapubkey_if {
359 rsa_checksig_fn *check;
362 /* RSAPRIVKEY interface */
364 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
365 struct rsaprivkey_if {
367 rsa_makesig_fn *sign;
373 /* This struct is pure data; in particular comm's clients may
375 struct comm_if *comm;
377 int ix; /* see comment `Re comm_addr.ix' in udp.c */
380 /* Return True if the packet was processed, and shouldn't be passed to
381 any other potential receivers. (buf is freed iff True returned.) */
382 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
383 const struct comm_addr *source);
384 typedef void comm_request_notify_fn(void *commst, void *nst,
386 typedef void comm_release_notify_fn(void *commst, void *nst,
388 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
389 const struct comm_addr *dest);
390 /* Only returns false if (we know that) the local network
391 * environment is such that this address cannot work; transient
392 * or unknown/unexpected failures return true. */
393 typedef const char *comm_addr_to_string_fn(void *commst,
394 const struct comm_addr *ca);
395 /* Returned string is in a static buffer. */
398 comm_request_notify_fn *request_notify;
399 comm_release_notify_fn *release_notify;
400 comm_sendmsg_fn *sendmsg;
401 comm_addr_to_string_fn *addr_to_string;
404 bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib);
406 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
408 return ca->comm->addr_to_string(ca->comm->st, ca);
411 static inline bool_t comm_addr_equal(const struct comm_addr *a,
412 const struct comm_addr *b)
414 return a->comm==b->comm && iaddr_equal(&a->ia,&b->ia);
419 #define LOG_MESSAGE_BUFLEN 1023
421 typedef void log_msg_fn(void *st, int class, const char *message, ...);
422 typedef void log_vmsg_fn(void *st, int class, const char *message,
426 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
427 char buff[LOG_MESSAGE_BUFLEN+1];
429 /* (convenience functions, defined in util.c) */
430 extern void slilog(struct log_if *lf, int class, const char *message, ...)
432 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
435 /* Versions which take (parts of) (multiple) messages, using \n to
436 * distinguish one message from another. */
437 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
439 extern void vslilog_part(struct log_if *lf, int class, const char *message,
440 va_list) FORMAT(printf,3,0);
444 /* Pretty much a placeholder; allows starting and stopping of processing,
446 typedef void site_control_fn(void *st, bool_t run);
447 typedef uint32_t site_status_fn(void *st);
450 site_control_fn *control;
451 site_status_fn *status;
454 /* TRANSFORM interface */
456 /* A reversable transformation. Transforms buffer in-place; may add
457 data to start or end. (Reverse transformations decrease
458 length, of course.) Transformations may be key-dependent, in which
459 case key material is passed in at initialisation time. They may
460 also depend on internal factors (eg. time) and keep internal
461 state. A struct transform_if only represents a particular type of
462 transformation; instances of the transformation (eg. with
463 particular key material) have a different C type. The same
464 secret key will be used in opposite directions between a pair of
465 secnets; one of these pairs will get direction==False, the other True. */
467 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
468 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
470 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
471 typedef void transform_delkey_fn(void *st);
472 typedef void transform_destroyinstance_fn(void *st);
475 * 1: for any other problem
476 * 2: message decrypted but sequence number was out of range
478 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
479 const char **errmsg);
481 struct transform_inst_if {
483 transform_setkey_fn *setkey;
484 transform_valid_fn *valid;
485 transform_delkey_fn *delkey;
486 transform_apply_fn *forwards;
487 transform_apply_fn *reverse;
488 transform_destroyinstance_fn *destroy;
491 struct transform_if {
493 int capab_transformnum;
494 int32_t keylen; /* <<< INT_MAX */
495 transform_createinstance_fn *create;
498 /* NETLINK interface */
500 /* Used by netlink to deliver to site, and by site to deliver to
501 netlink. cid is the client identifier returned by
502 netlink_regnets_fn. If buf has size 0 then the function is just
503 being called for its site-effects (eg. making the site code attempt
504 to bring up a network link) */
505 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
506 /* site code can tell netlink when outgoing packets will be dropped,
507 so netlink can generate appropriate ICMP and make routing decisions */
508 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
509 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
510 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
511 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
512 #define LINK_QUALITY_UP 4 /* Link active */
513 #define MAXIMUM_LINK_QUALITY 3
514 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
515 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
516 void *dst, uint32_t *localmtu_r /* NULL ok */);
517 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
518 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
519 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
522 netlink_register_fn *reg;
523 netlink_deliver_fn *deliver;
524 netlink_link_quality_fn *set_quality;
525 netlink_set_mtu_fn *set_mtu;
530 /* Returns public key as a malloced hex string */
531 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
533 /* Fills buffer (up to buflen) with shared secret */
534 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
535 int32_t secretlen, cstring_t rempublic,
536 uint8_t *sharedsecret, int32_t buflen);
539 int32_t len; /* Approximate size of modulus in bytes */
540 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
541 dh_makepublic_fn *makepublic;
542 dh_makeshared_fn *makeshared;
547 typedef void *hash_init_fn(void);
548 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
549 typedef void hash_final_fn(void *st, uint8_t *digest);
551 int32_t len; /* Hash output length in bytes */
553 hash_update_fn *update;
554 hash_final_fn *final;
557 /* BUFFER interface */
561 cstring_t owner; /* Set to constant string */
562 uint32_t flags; /* How paranoid should we be? */
563 struct cloc loc; /* Where we were defined */
566 int32_t size; /* Size of buffer contents */
567 int32_t alloclen; /* Total length allocated at base */
570 /***** LOG functions *****/
572 #define M_DEBUG_CONFIG 0x001
573 #define M_DEBUG_PHASE 0x002
574 #define M_DEBUG 0x004
576 #define M_NOTICE 0x010
577 #define M_WARNING 0x020
579 #define M_SECURITY 0x080
580 #define M_FATAL 0x100
582 /* The fatal() family of functions require messages that do not end in '\n' */
583 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
584 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
585 extern NORETURN(fatal_status(int status, const char *message, ...))
587 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
590 /* Convenient nonfatal logging. Requires message that does not end in '\n'.
591 * If class contains M_FATAL, exits (after entering PHASE_SHUTDOWN).
592 * lg, errnoval and loc may sensibly be 0. desc must NOT be 0.
593 * lg_[v]perror save and restore errno. */
594 void lg_vperror(struct log_if *lg, const char *desc, struct cloc *loc,
595 int class, int errnoval, const char *fmt, va_list al)
597 void lg_perror(struct log_if *lg, const char *desc, struct cloc *loc,
598 int class, int errnoval, const char *fmt, ...)
601 /* The cfgfatal() family of functions require messages that end in '\n' */
602 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
603 const char *message, ...)) FORMAT(printf,3,4);
604 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
605 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
606 cstring_t facility, const char *message,
609 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
611 const char *message, ...))
614 extern void Message(uint32_t class, const char *message, ...)
616 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
618 /***** END of log functions *****/
620 #define STRING2(x) #x
621 #define STRING(x) STRING2(x)
623 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
624 #define ARRAY_SIZE(ary) (sizeof((ary))/sizeof((ary)[0]))
627 * void COPY_OBJ( OBJECT& dst, const OBJECT& src);
628 * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
629 * // Typesafe: we check that the type OBJECT is the same in both cases.
630 * // It is OK to use COPY_OBJ on an array object, provided it's
631 * // _actually_ the whole array object and not decayed into a
632 * // pointer (e.g. a formal parameter).
634 #define COPY_OBJ(dst,src) \
635 (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
636 #define COPY_ARRAY(dst,src,count) \
637 (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
639 #endif /* secnet_h */