1 /* Core interface of secnet, to be used by all modules */
6 #define ADNS_FEATURE_MANYAF
18 #include <sys/types.h>
21 #include <netinet/in.h>
22 #include <arpa/inet.h>
24 #include <bsd/sys/queue.h>
26 #define MAX_PEER_ADDRS 5
27 /* send at most this many copies; honour at most that many addresses */
32 typedef char *string_t;
33 typedef const char *cstring_t;
35 #define False (_Bool)0
41 struct sockaddr_in sin;
43 struct sockaddr_in6 sin6;
47 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
48 __FILE__,__LINE__); } } while(0)
52 extern char version[];
55 extern uint32_t message_level;
56 extern bool_t secnet_is_daemon;
57 extern struct log_if *system_log;
60 extern void start_signal_handling(void);
63 /* Must be called before exec in every child made after
64 start_signal_handling. Safe to call in earlier children too. */
66 /***** CONFIGURATION support *****/
68 extern bool_t just_check_config; /* If True then we're going to exit after
69 reading the configuration file */
70 extern bool_t background; /* If True then we'll eventually run as a daemon */
72 typedef struct dict dict_t; /* Configuration dictionary */
73 typedef struct closure closure_t;
74 typedef struct item item_t;
75 typedef struct list list_t; /* A list of items */
77 /* Configuration file location, for error-reporting */
83 /* Modules export closures, which can be invoked from the configuration file.
84 "Invoking" a closure usually returns another closure (of a different
85 type), but can actually return any configuration object. */
86 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
87 dict_t *context, list_t *data);
89 cstring_t description; /* For debugging */
90 uint32_t type; /* Central registry... */
92 void *interface; /* Interface for use inside secnet; depends on type */
95 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
108 /* Note that it is unwise to use this structure directly; use the list
109 manipulation functions instead. */
115 /* In the following two lookup functions, NULL means 'not found' */
116 /* Lookup a value in the specified dictionary, or its parents */
117 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
118 /* Lookup a value in just the specified dictionary */
119 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
120 /* Add a value to the specified dictionary */
121 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
122 /* Obtain an array of keys in the dictionary. malloced; caller frees */
123 extern cstring_t *dict_keys(dict_t *dict);
125 /* List-manipulation functions */
126 extern list_t *list_new(void);
127 extern int32_t list_length(const list_t *a);
128 extern list_t *list_append(list_t *a, item_t *i);
129 extern list_t *list_append_list(list_t *a, list_t *b);
130 /* Returns an item from the list (index starts at 0), or NULL */
131 extern item_t *list_elem(list_t *l, int32_t index);
133 /* Convenience functions */
134 extern list_t *new_closure(closure_t *cl);
135 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
136 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
137 bool_t fail_if_invalid, cstring_t desc,
139 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
140 cstring_t desc, struct cloc loc);
141 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
142 cstring_t desc, struct cloc loc);
143 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
144 cstring_t desc, struct cloc loc,
146 /* return value can safely be assigned to int32_t */
147 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
148 cstring_t desc, struct cloc loc, bool_t def);
149 const char **dict_read_string_array(dict_t *dict, cstring_t key,
150 bool_t required, cstring_t desc,
151 struct cloc loc, const char *const *def);
152 /* Return value is a NULL-terminated array obtained from malloc;
153 * Individual string values are still owned by config file machinery
154 * and must not be modified or freed. Returns NULL if key not
161 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
162 struct flagstr *f, cstring_t desc);
163 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
166 /***** END of configuration support *****/
168 /***** UTILITY functions *****/
170 extern char *safe_strdup(const char *string, const char *message);
171 extern void *safe_malloc(size_t size, const char *message);
172 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
173 extern void *safe_realloc_ary(void *p, size_t size, size_t count,
174 const char *message);
176 void setcloexec(int fd); /* cannot fail */
177 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
179 extern int sys_cmd(const char *file, const char *argc, ...);
181 extern uint64_t now_global;
182 extern struct timeval tv_now_global;
184 static const uint64_t *const now = &now_global;
185 static const struct timeval *const tv_now = &tv_now_global;
187 /* "now" is current program time, in milliseconds. It is derived
188 from tv_now. Both are provided by the event loop. */
190 /***** END of utility functions *****/
192 /***** START of max_start_pad handling *****/
194 extern int32_t site_max_start_pad, transform_max_start_pad,
197 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
198 int32_t calculate_max_start_pad(void);
200 /***** END of max_start_pad handling *****/
202 /***** SCHEDULING support */
204 /* If nfds_io is insufficient for your needs, set it to the required
205 number and return ERANGE. timeout is in milliseconds; if it is too
206 high then lower it. It starts at -1 (==infinite). */
207 /* Note that beforepoll_fn may NOT do anything which might change the
208 fds or timeouts wanted by other registered poll loop loopers.
209 Callers should make sure of this by not making any calls into other
210 modules from the beforepoll_fn; the easiest way to ensure this is
211 for beforepoll_fn to only retreive information and not take any
214 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
216 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
218 /* void BEFOREPOLL_WANT_FDS(int want);
219 * Expects: int *nfds_io;
220 * Can perform non-local exit.
221 * Checks whether there is space for want fds. If so, sets *nfds_io.
222 * If not, sets *nfds_io and returns. */
223 #define BEFOREPOLL_WANT_FDS(want) do{ \
224 if (*nfds_io<(want)) { *nfds_io=(want); return ERANGE; } \
228 /* Register interest in the main loop of the program. Before a call
229 to poll() your supplied beforepoll function will be called. After
230 the call to poll() the supplied afterpoll function will be called. */
231 struct poll_interest *register_for_poll(void *st, beforepoll_fn *before,
232 afterpoll_fn *after, cstring_t desc);
233 void deregister_for_poll(struct poll_interest *i);
235 /***** END of scheduling support */
237 /***** PROGRAM LIFETIME support */
239 /* The secnet program goes through a number of phases in its lifetime.
240 Module code may arrange to be called just as various phases are
243 Remember to update the table in util.c if changing the set of
248 PHASE_GETOPTS, /* Process command-line arguments */
249 PHASE_READCONFIG, /* Parse and process configuration file */
250 PHASE_SETUP, /* Process information in configuration */
251 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
252 PHASE_GETRESOURCES, /* Obtain all external resources */
253 PHASE_DROPPRIV, /* Last chance for privileged operations */
255 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
256 /* Keep this last: */
260 typedef void hook_fn(void *self, uint32_t newphase);
261 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
262 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
264 extern uint32_t current_phase;
265 extern void enter_phase(uint32_t new_phase);
267 /* Some features (like netlink 'soft' routes) require that secnet
268 retain root privileges. They should indicate that here when
270 extern bool_t require_root_privileges;
271 extern cstring_t require_root_privileges_explanation;
273 /***** END of program lifetime support *****/
275 /***** MODULE support *****/
277 /* Module initialisation function type - modules export one function of
278 this type which is called to initialise them. For dynamically loaded
279 modules it's called "secnet_module". */
280 typedef void init_module(dict_t *dict);
282 extern void init_builtin_modules(dict_t *dict);
284 extern init_module resolver_module;
285 extern init_module random_module;
286 extern init_module udp_module;
287 extern init_module util_module;
288 extern init_module site_module;
289 extern init_module transform_eax_module;
290 extern init_module transform_cbcmac_module;
291 extern init_module netlink_module;
292 extern init_module rsa_module;
293 extern init_module dh_module;
294 extern init_module md5_module;
295 extern init_module slip_module;
296 extern init_module tun_module;
297 extern init_module sha1_module;
298 extern init_module log_module;
300 /***** END of module support *****/
302 /***** CLOSURE TYPES and interface definitions *****/
305 #define CL_RESOLVER 1
306 #define CL_RANDOMSRC 2
307 #define CL_RSAPUBKEY 3
308 #define CL_RSAPRIVKEY 4
313 #define CL_TRANSFORM 9
317 #define CL_NETLINK 14
321 /* PURE closure requires no interface */
323 /* RESOLVER interface */
325 /* Answers to queries are delivered to a function of this
326 type. 'address' will be NULL if there was a problem with the query. It
327 will be freed once resolve_answer_fn returns. It is in network byte
329 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
330 int naddrs, const char *name,
331 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 /* Everyone is also guaranteed that all padding is set to zero, ie
376 that comm_addrs referring to semantically identical peers will
377 compare equal with memcmp. Anyone who constructs a comm_addr
378 must start by memsetting it with FILLZERO, or some
380 struct comm_if *comm;
385 /* Return True if the packet was processed, and shouldn't be passed to
386 any other potential receivers. (buf is freed iff True returned.) */
387 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
388 const struct comm_addr *source);
389 typedef void comm_request_notify_fn(void *commst, void *nst,
391 typedef void comm_release_notify_fn(void *commst, void *nst,
393 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
394 const struct comm_addr *dest);
395 /* Only returns false if (we know that) the local network
396 * environment is such that this address cannot work; transient
397 * or unknown/unexpected failures return true. */
398 typedef const char *comm_addr_to_string_fn(void *commst,
399 const struct comm_addr *ca);
400 /* Returned string is in a static buffer. */
403 comm_request_notify_fn *request_notify;
404 comm_release_notify_fn *release_notify;
405 comm_sendmsg_fn *sendmsg;
406 comm_addr_to_string_fn *addr_to_string;
409 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
411 return ca->comm->addr_to_string(ca->comm->st, ca);
416 #define LOG_MESSAGE_BUFLEN 1023
418 typedef void log_msg_fn(void *st, int class, const char *message, ...);
419 typedef void log_vmsg_fn(void *st, int class, const char *message,
423 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
424 char buff[LOG_MESSAGE_BUFLEN+1];
426 /* (convenience functions, defined in util.c) */
427 extern void slilog(struct log_if *lf, int class, const char *message, ...)
429 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
432 /* Versions which take (parts of) (multiple) messages, using \n to
433 * distinguish one message from another. */
434 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
436 extern void vslilog_part(struct log_if *lf, int class, const char *message,
437 va_list) FORMAT(printf,3,0);
441 /* Pretty much a placeholder; allows starting and stopping of processing,
443 typedef void site_control_fn(void *st, bool_t run);
444 typedef uint32_t site_status_fn(void *st);
447 site_control_fn *control;
448 site_status_fn *status;
451 /* TRANSFORM interface */
453 /* A reversable transformation. Transforms buffer in-place; may add
454 data to start or end. (Reverse transformations decrease
455 length, of course.) Transformations may be key-dependent, in which
456 case key material is passed in at initialisation time. They may
457 also depend on internal factors (eg. time) and keep internal
458 state. A struct transform_if only represents a particular type of
459 transformation; instances of the transformation (eg. with
460 particular key material) have a different C type. The same
461 secret key will be used in opposite directions between a pair of
462 secnets; one of these pairs will get direction==False, the other True. */
464 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
465 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
467 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
468 typedef void transform_delkey_fn(void *st);
469 typedef void transform_destroyinstance_fn(void *st);
472 * 1: for any other problem
473 * 2: message decrypted but sequence number was out of range
475 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
476 const char **errmsg);
478 struct transform_inst_if {
480 transform_setkey_fn *setkey;
481 transform_valid_fn *valid;
482 transform_delkey_fn *delkey;
483 transform_apply_fn *forwards;
484 transform_apply_fn *reverse;
485 transform_destroyinstance_fn *destroy;
488 struct transform_if {
490 int capab_transformnum;
491 int32_t keylen; /* <<< INT_MAX */
492 transform_createinstance_fn *create;
495 /* NETLINK interface */
497 /* Used by netlink to deliver to site, and by site to deliver to
498 netlink. cid is the client identifier returned by
499 netlink_regnets_fn. If buf has size 0 then the function is just
500 being called for its site-effects (eg. making the site code attempt
501 to bring up a network link) */
502 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
503 /* site code can tell netlink when outgoing packets will be dropped,
504 so netlink can generate appropriate ICMP and make routing decisions */
505 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
506 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
507 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
508 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
509 #define LINK_QUALITY_UP 4 /* Link active */
510 #define MAXIMUM_LINK_QUALITY 3
511 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
512 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
513 void *dst, uint32_t *localmtu_r /* NULL ok */);
514 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
515 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
516 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
519 netlink_register_fn *reg;
520 netlink_deliver_fn *deliver;
521 netlink_link_quality_fn *set_quality;
522 netlink_set_mtu_fn *set_mtu;
527 /* Returns public key as a malloced hex string */
528 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
530 /* Fills buffer (up to buflen) with shared secret */
531 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
532 int32_t secretlen, cstring_t rempublic,
533 uint8_t *sharedsecret, int32_t buflen);
536 int32_t len; /* Approximate size of modulus in bytes */
537 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
538 dh_makepublic_fn *makepublic;
539 dh_makeshared_fn *makeshared;
544 typedef void *hash_init_fn(void);
545 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
546 typedef void hash_final_fn(void *st, uint8_t *digest);
548 int32_t len; /* Hash output length in bytes */
550 hash_update_fn *update;
551 hash_final_fn *final;
554 /* BUFFER interface */
558 cstring_t owner; /* Set to constant string */
559 uint32_t flags; /* How paranoid should we be? */
560 struct cloc loc; /* Where we were defined */
563 int32_t size; /* Size of buffer contents */
564 int32_t alloclen; /* Total length allocated at base */
567 /***** LOG functions *****/
569 #define M_DEBUG_CONFIG 0x001
570 #define M_DEBUG_PHASE 0x002
571 #define M_DEBUG 0x004
573 #define M_NOTICE 0x010
574 #define M_WARNING 0x020
576 #define M_SECURITY 0x080
577 #define M_FATAL 0x100
579 /* The fatal() family of functions require messages that do not end in '\n' */
580 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
581 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
582 extern NORETURN(fatal_status(int status, const char *message, ...))
584 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
587 /* Convenient nonfatal logging. Requires message that does not end in '\n'.
588 * If class contains M_FATAL, exits (after entering PHASE_SHUTDOWN).
589 * lg, errnoval and loc may sensibly be 0. desc must NOT be 0.
590 * lg_[v]perror save and restore errno. */
591 void lg_vperror(struct log_if *lg, const char *desc, struct cloc *loc,
592 int class, int errnoval, const char *fmt, va_list al)
594 void lg_perror(struct log_if *lg, const char *desc, struct cloc *loc,
595 int class, int errnoval, const char *fmt, ...)
597 void lg_exitstatus(struct log_if *lg, const char *desc, struct cloc *loc,
598 int class, int status, const char *progname);
600 /* The cfgfatal() family of functions require messages that end in '\n' */
601 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
602 const char *message, ...)) FORMAT(printf,3,4);
603 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
604 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
605 cstring_t facility, const char *message,
608 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
610 const char *message, ...))
613 extern void Message(uint32_t class, const char *message, ...)
615 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
617 /***** END of log functions *****/
619 #define STRING2(x) #x
620 #define STRING(x) STRING2(x)
622 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
623 #define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
625 #endif /* secnet_h */