1 /* Core interface of secnet, to be used by all modules */
6 #define ADNS_FEATURE_MANYAF
17 #include <sys/types.h>
19 #include <netinet/in.h>
20 #include <arpa/inet.h>
22 #define MAX_PEER_ADDRS 5
23 /* send at most this many copies; honour at most that many addresses */
28 typedef char *string_t;
29 typedef const char *cstring_t;
31 #define False (_Bool)0
37 struct sockaddr_in sin;
39 struct sockaddr_in6 sin6;
43 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
44 __FILE__,__LINE__); } } while(0)
48 extern char version[];
51 extern uint32_t message_level;
52 extern bool_t secnet_is_daemon;
53 extern struct log_if *system_log;
56 extern void start_signal_handling(void);
58 /***** CONFIGURATION support *****/
60 extern bool_t just_check_config; /* If True then we're going to exit after
61 reading the configuration file */
62 extern bool_t background; /* If True then we'll eventually run as a daemon */
64 typedef struct dict dict_t; /* Configuration dictionary */
65 typedef struct closure closure_t;
66 typedef struct item item_t;
67 typedef struct list list_t; /* A list of items */
69 /* Configuration file location, for error-reporting */
75 /* Modules export closures, which can be invoked from the configuration file.
76 "Invoking" a closure usually returns another closure (of a different
77 type), but can actually return any configuration object. */
78 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
79 dict_t *context, list_t *data);
81 cstring_t description; /* For debugging */
82 uint32_t type; /* Central registry... */
84 void *interface; /* Interface for use inside secnet; depends on type */
87 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
100 /* Note that it is unwise to use this structure directly; use the list
101 manipulation functions instead. */
107 /* In the following two lookup functions, NULL means 'not found' */
108 /* Lookup a value in the specified dictionary, or its parents */
109 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
110 /* Lookup a value in just the specified dictionary */
111 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
112 /* Add a value to the specified dictionary */
113 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
114 /* Obtain an array of keys in the dictionary. malloced; caller frees */
115 extern cstring_t *dict_keys(dict_t *dict);
117 /* List-manipulation functions */
118 extern list_t *list_new(void);
119 extern int32_t list_length(const list_t *a);
120 extern list_t *list_append(list_t *a, item_t *i);
121 extern list_t *list_append_list(list_t *a, list_t *b);
122 /* Returns an item from the list (index starts at 0), or NULL */
123 extern item_t *list_elem(list_t *l, int32_t index);
125 /* Convenience functions */
126 extern list_t *new_closure(closure_t *cl);
127 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
128 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
129 bool_t fail_if_invalid, cstring_t desc,
131 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
132 cstring_t desc, struct cloc loc);
133 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
134 cstring_t desc, struct cloc loc);
135 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
136 cstring_t desc, struct cloc loc,
138 /* return value can safely be assigned to int32_t */
139 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
140 cstring_t desc, struct cloc loc, bool_t def);
145 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
146 struct flagstr *f, cstring_t desc);
147 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
150 /***** END of configuration support *****/
152 /***** UTILITY functions *****/
154 extern char *safe_strdup(const char *string, const char *message);
155 extern void *safe_malloc(size_t size, const char *message);
156 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
158 void setcloexec(int fd); /* cannot fail */
159 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
161 extern int sys_cmd(const char *file, const char *argc, ...);
163 extern uint64_t now_global;
164 extern struct timeval tv_now_global;
166 static const uint64_t *const now = &now_global;
167 static const struct timeval *const tv_now = &tv_now_global;
169 /* "now" is current program time, in milliseconds. It is derived
170 from tv_now. Both are provided by the event loop. */
172 /***** END of utility functions *****/
174 /***** START of max_start_pad handling *****/
176 extern int32_t site_max_start_pad, transform_max_start_pad,
179 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
180 int32_t calculate_max_start_pad(void);
182 /***** END of max_start_pad handling *****/
184 /***** SCHEDULING support */
186 /* If nfds_io is insufficient for your needs, set it to the required
187 number and return ERANGE. timeout is in milliseconds; if it is too
188 high then lower it. It starts at -1 (==infinite) */
189 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
191 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
193 /* Register interest in the main loop of the program. Before a call
194 to poll() your supplied beforepoll function will be called. After
195 the call to poll() the supplied afterpoll function will be called.
196 max_nfds is a _hint_ about the maximum number of struct pollfd
197 structures you may require - you can always ask for more in
199 extern void register_for_poll(void *st, beforepoll_fn *before,
200 afterpoll_fn *after, int32_t max_nfds,
203 /***** END of scheduling support */
205 /***** PROGRAM LIFETIME support */
207 /* The secnet program goes through a number of phases in its lifetime.
208 Module code may arrange to be called just as various phases are
211 Remember to update the table in util.c if changing the set of
216 PHASE_GETOPTS, /* Process command-line arguments */
217 PHASE_READCONFIG, /* Parse and process configuration file */
218 PHASE_SETUP, /* Process information in configuration */
219 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
220 PHASE_GETRESOURCES, /* Obtain all external resources */
221 PHASE_DROPPRIV, /* Last chance for privileged operations */
223 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
224 /* Keep this last: */
228 typedef void hook_fn(void *self, uint32_t newphase);
229 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
230 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
232 extern uint32_t current_phase;
233 extern void enter_phase(uint32_t new_phase);
235 /* Some features (like netlink 'soft' routes) require that secnet
236 retain root privileges. They should indicate that here when
238 extern bool_t require_root_privileges;
239 extern cstring_t require_root_privileges_explanation;
241 /***** END of program lifetime support *****/
243 /***** MODULE support *****/
245 /* Module initialisation function type - modules export one function of
246 this type which is called to initialise them. For dynamically loaded
247 modules it's called "secnet_module". */
248 typedef void init_module(dict_t *dict);
250 extern void init_builtin_modules(dict_t *dict);
252 extern init_module resolver_module;
253 extern init_module random_module;
254 extern init_module udp_module;
255 extern init_module util_module;
256 extern init_module site_module;
257 extern init_module transform_eax_module;
258 extern init_module transform_cbcmac_module;
259 extern init_module netlink_module;
260 extern init_module rsa_module;
261 extern init_module dh_module;
262 extern init_module md5_module;
263 extern init_module slip_module;
264 extern init_module tun_module;
265 extern init_module sha1_module;
266 extern init_module log_module;
268 /***** END of module support *****/
270 /***** CLOSURE TYPES and interface definitions *****/
273 #define CL_RESOLVER 1
274 #define CL_RANDOMSRC 2
275 #define CL_RSAPUBKEY 3
276 #define CL_RSAPRIVKEY 4
281 #define CL_TRANSFORM 9
285 #define CL_NETLINK 14
289 /* PURE closure requires no interface */
291 /* RESOLVER interface */
293 /* Answers to queries are delivered to a function of this
294 type. 'address' will be NULL if there was a problem with the query. It
295 will be freed once resolve_answer_fn returns. naddrs is the actual
296 size of the array at addrs; was_naddrs is the number of addresses
297 actually found in the DNS, which may be bigger if addrs is equal
298 to MAX_PEER_ADDRS (ie there were too many). */
299 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
300 int naddrs, int was_naddrs,
301 const char *name, const char *failwhy);
302 /* name is the same ptr as passed to request, so its lifetime must
304 typedef bool_t resolve_request_fn(void *st, cstring_t name,
305 int remoteport, struct comm_if *comm,
306 resolve_answer_fn *cb, void *cst);
309 resolve_request_fn *request;
312 /* RANDOMSRC interface */
314 /* Return some random data. Returns TRUE for success. */
315 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
323 /* RSAPUBKEY interface */
325 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
326 cstring_t signature);
327 struct rsapubkey_if {
329 rsa_checksig_fn *check;
332 /* RSAPRIVKEY interface */
334 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
335 struct rsaprivkey_if {
337 rsa_makesig_fn *sign;
343 /* This struct is pure data; in particular comm's clients may
345 struct comm_if *comm;
347 int ix; /* see comment `Re comm_addr.ix' in udp.c */
350 /* Return True if the packet was processed, and shouldn't be passed to
351 any other potential receivers. */
352 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
353 const struct comm_addr *source);
354 typedef void comm_request_notify_fn(void *commst, void *nst,
356 typedef void comm_release_notify_fn(void *commst, void *nst,
358 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
359 const struct comm_addr *dest);
360 /* Only returns false if (we know that) the local network
361 * environment is such that this address cannot work; transient
362 * or unknown/unexpected failures return true. */
363 typedef const char *comm_addr_to_string_fn(void *commst,
364 const struct comm_addr *ca);
365 /* Returned string is in a static buffer. */
368 comm_request_notify_fn *request_notify;
369 comm_release_notify_fn *release_notify;
370 comm_sendmsg_fn *sendmsg;
371 comm_addr_to_string_fn *addr_to_string;
374 bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib);
376 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
378 return ca->comm->addr_to_string(ca->comm->st, ca);
381 static inline bool_t comm_addr_equal(const struct comm_addr *a,
382 const struct comm_addr *b)
384 return a->comm==b->comm && iaddr_equal(&a->ia,&b->ia);
389 #define LOG_MESSAGE_BUFLEN 1023
391 typedef void log_msg_fn(void *st, int class, const char *message, ...);
392 typedef void log_vmsg_fn(void *st, int class, const char *message,
396 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
397 char buff[LOG_MESSAGE_BUFLEN+1];
399 /* (convenience functions, defined in util.c) */
400 extern void slilog(struct log_if *lf, int class, const char *message, ...)
402 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
405 /* Versions which take (parts of) (multiple) messages, using \n to
406 * distinguish one message from another. */
407 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
409 extern void vslilog_part(struct log_if *lf, int class, const char *message,
410 va_list) FORMAT(printf,3,0);
414 /* Pretty much a placeholder; allows starting and stopping of processing,
416 typedef void site_control_fn(void *st, bool_t run);
417 typedef uint32_t site_status_fn(void *st);
420 site_control_fn *control;
421 site_status_fn *status;
424 /* TRANSFORM interface */
426 /* A reversable transformation. Transforms buffer in-place; may add
427 data to start or end. (Reverse transformations decrease
428 length, of course.) Transformations may be key-dependent, in which
429 case key material is passed in at initialisation time. They may
430 also depend on internal factors (eg. time) and keep internal
431 state. A struct transform_if only represents a particular type of
432 transformation; instances of the transformation (eg. with
433 particular key material) have a different C type. The same
434 secret key will be used in opposite directions between a pair of
435 secnets; one of these pairs will get direction==False, the other True. */
437 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
438 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
440 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
441 typedef void transform_delkey_fn(void *st);
442 typedef void transform_destroyinstance_fn(void *st);
445 * 1: for any other problem
446 * 2: message decrypted but sequence number was out of range
448 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
449 const char **errmsg);
451 struct transform_inst_if {
453 transform_setkey_fn *setkey;
454 transform_valid_fn *valid;
455 transform_delkey_fn *delkey;
456 transform_apply_fn *forwards;
457 transform_apply_fn *reverse;
458 transform_destroyinstance_fn *destroy;
461 struct transform_if {
463 int capab_transformnum;
464 int32_t keylen; /* <<< INT_MAX */
465 transform_createinstance_fn *create;
468 /* NETLINK interface */
470 /* Used by netlink to deliver to site, and by site to deliver to
471 netlink. cid is the client identifier returned by
472 netlink_regnets_fn. If buf has size 0 then the function is just
473 being called for its site-effects (eg. making the site code attempt
474 to bring up a network link) */
475 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
476 /* site code can tell netlink when outgoing packets will be dropped,
477 so netlink can generate appropriate ICMP and make routing decisions */
478 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
479 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
480 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
481 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
482 #define LINK_QUALITY_UP 4 /* Link active */
483 #define MAXIMUM_LINK_QUALITY 3
484 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
485 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
486 void *dst, uint32_t *localmtu_r /* NULL ok */);
487 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
488 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
489 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
492 netlink_register_fn *reg;
493 netlink_deliver_fn *deliver;
494 netlink_link_quality_fn *set_quality;
495 netlink_set_mtu_fn *set_mtu;
500 /* Returns public key as a malloced hex string */
501 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
503 /* Fills buffer (up to buflen) with shared secret */
504 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
505 int32_t secretlen, cstring_t rempublic,
506 uint8_t *sharedsecret, int32_t buflen);
509 int32_t len; /* Approximate size of modulus in bytes */
510 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
511 dh_makepublic_fn *makepublic;
512 dh_makeshared_fn *makeshared;
517 typedef void *hash_init_fn(void);
518 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
519 typedef void hash_final_fn(void *st, uint8_t *digest);
521 int32_t len; /* Hash output length in bytes */
523 hash_update_fn *update;
524 hash_final_fn *final;
527 /* BUFFER interface */
531 cstring_t owner; /* Set to constant string */
532 uint32_t flags; /* How paranoid should we be? */
533 struct cloc loc; /* Where we were defined */
536 int32_t size; /* Size of buffer contents */
537 int32_t alloclen; /* Total length allocated at base */
540 /***** LOG functions *****/
542 #define M_DEBUG_CONFIG 0x001
543 #define M_DEBUG_PHASE 0x002
544 #define M_DEBUG 0x004
546 #define M_NOTICE 0x010
547 #define M_WARNING 0x020
549 #define M_SECURITY 0x080
550 #define M_FATAL 0x100
552 /* The fatal() family of functions require messages that do not end in '\n' */
553 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
554 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
555 extern NORETURN(fatal_status(int status, const char *message, ...))
557 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
560 /* The cfgfatal() family of functions require messages that end in '\n' */
561 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
562 const char *message, ...)) FORMAT(printf,3,4);
563 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
564 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
565 cstring_t facility, const char *message,
568 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
570 const char *message, ...))
573 extern void Message(uint32_t class, const char *message, ...)
575 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
577 /***** END of log functions *****/
579 #define STRING2(x) #x
580 #define STRING(x) STRING2(x)
582 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
583 #define ARRAY_SIZE(ary) (sizeof((ary))/sizeof((ary)[0]))
586 * void COPY_OBJ( OBJECT& dst, const OBJECT& src);
587 * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
588 * // Typesafe: we check that the type OBJECT is the same in both cases.
589 * // It is OK to use COPY_OBJ on an array object, provided it's
590 * // _actually_ the whole array object and not decayed into a
591 * // pointer (e.g. a formal parameter).
593 #define COPY_OBJ(dst,src) \
594 (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
595 #define COPY_ARRAY(dst,src,count) \
596 (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
598 #endif /* secnet_h */