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 typedef bool_t resolve_request_fn(void *st, cstring_t name,
302 int remoteport, struct comm_if *comm,
303 resolve_answer_fn *cb, void *cst);
306 resolve_request_fn *request;
309 /* RANDOMSRC interface */
311 /* Return some random data. Returns TRUE for success. */
312 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
320 /* RSAPUBKEY interface */
322 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
323 cstring_t signature);
324 struct rsapubkey_if {
326 rsa_checksig_fn *check;
329 /* RSAPRIVKEY interface */
331 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
332 struct rsaprivkey_if {
334 rsa_makesig_fn *sign;
340 /* This struct is pure data; in particular comm's clients may
342 struct comm_if *comm;
344 int ix; /* see comment `Re comm_addr.ix' in udp.c */
347 /* Return True if the packet was processed, and shouldn't be passed to
348 any other potential receivers. */
349 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
350 const struct comm_addr *source);
351 typedef void comm_request_notify_fn(void *commst, void *nst,
353 typedef void comm_release_notify_fn(void *commst, void *nst,
355 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
356 const struct comm_addr *dest);
357 /* Only returns false if (we know that) the local network
358 * environment is such that this address cannot work; transient
359 * or unknown/unexpected failures return true. */
360 typedef const char *comm_addr_to_string_fn(void *commst,
361 const struct comm_addr *ca);
362 /* Returned string is in a static buffer. */
365 comm_request_notify_fn *request_notify;
366 comm_release_notify_fn *release_notify;
367 comm_sendmsg_fn *sendmsg;
368 comm_addr_to_string_fn *addr_to_string;
371 bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib);
373 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
375 return ca->comm->addr_to_string(ca->comm->st, ca);
378 static inline bool_t comm_addr_equal(const struct comm_addr *a,
379 const struct comm_addr *b)
381 return a->comm==b->comm && iaddr_equal(&a->ia,&b->ia);
386 #define LOG_MESSAGE_BUFLEN 1023
388 typedef void log_msg_fn(void *st, int class, const char *message, ...);
389 typedef void log_vmsg_fn(void *st, int class, const char *message,
393 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
394 char buff[LOG_MESSAGE_BUFLEN+1];
396 /* (convenience functions, defined in util.c) */
397 extern void slilog(struct log_if *lf, int class, const char *message, ...)
399 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
402 /* Versions which take (parts of) (multiple) messages, using \n to
403 * distinguish one message from another. */
404 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
406 extern void vslilog_part(struct log_if *lf, int class, const char *message,
407 va_list) FORMAT(printf,3,0);
411 /* Pretty much a placeholder; allows starting and stopping of processing,
413 typedef void site_control_fn(void *st, bool_t run);
414 typedef uint32_t site_status_fn(void *st);
417 site_control_fn *control;
418 site_status_fn *status;
421 /* TRANSFORM interface */
423 /* A reversable transformation. Transforms buffer in-place; may add
424 data to start or end. (Reverse transformations decrease
425 length, of course.) Transformations may be key-dependent, in which
426 case key material is passed in at initialisation time. They may
427 also depend on internal factors (eg. time) and keep internal
428 state. A struct transform_if only represents a particular type of
429 transformation; instances of the transformation (eg. with
430 particular key material) have a different C type. The same
431 secret key will be used in opposite directions between a pair of
432 secnets; one of these pairs will get direction==False, the other True. */
434 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
435 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
437 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
438 typedef void transform_delkey_fn(void *st);
439 typedef void transform_destroyinstance_fn(void *st);
442 * 1: for any other problem
443 * 2: message decrypted but sequence number was out of range
445 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
446 const char **errmsg);
448 struct transform_inst_if {
450 transform_setkey_fn *setkey;
451 transform_valid_fn *valid;
452 transform_delkey_fn *delkey;
453 transform_apply_fn *forwards;
454 transform_apply_fn *reverse;
455 transform_destroyinstance_fn *destroy;
458 struct transform_if {
460 int capab_transformnum;
461 int32_t keylen; /* <<< INT_MAX */
462 transform_createinstance_fn *create;
465 /* NETLINK interface */
467 /* Used by netlink to deliver to site, and by site to deliver to
468 netlink. cid is the client identifier returned by
469 netlink_regnets_fn. If buf has size 0 then the function is just
470 being called for its site-effects (eg. making the site code attempt
471 to bring up a network link) */
472 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
473 /* site code can tell netlink when outgoing packets will be dropped,
474 so netlink can generate appropriate ICMP and make routing decisions */
475 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
476 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
477 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
478 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
479 #define LINK_QUALITY_UP 4 /* Link active */
480 #define MAXIMUM_LINK_QUALITY 3
481 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
482 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
483 void *dst, uint32_t *localmtu_r /* NULL ok */);
484 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
485 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
486 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
489 netlink_register_fn *reg;
490 netlink_deliver_fn *deliver;
491 netlink_link_quality_fn *set_quality;
492 netlink_set_mtu_fn *set_mtu;
497 /* Returns public key as a malloced hex string */
498 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
500 /* Fills buffer (up to buflen) with shared secret */
501 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
502 int32_t secretlen, cstring_t rempublic,
503 uint8_t *sharedsecret, int32_t buflen);
506 int32_t len; /* Approximate size of modulus in bytes */
507 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
508 dh_makepublic_fn *makepublic;
509 dh_makeshared_fn *makeshared;
514 typedef void *hash_init_fn(void);
515 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
516 typedef void hash_final_fn(void *st, uint8_t *digest);
518 int32_t len; /* Hash output length in bytes */
520 hash_update_fn *update;
521 hash_final_fn *final;
524 /* BUFFER interface */
528 cstring_t owner; /* Set to constant string */
529 uint32_t flags; /* How paranoid should we be? */
530 struct cloc loc; /* Where we were defined */
533 int32_t size; /* Size of buffer contents */
534 int32_t alloclen; /* Total length allocated at base */
537 /***** LOG functions *****/
539 #define M_DEBUG_CONFIG 0x001
540 #define M_DEBUG_PHASE 0x002
541 #define M_DEBUG 0x004
543 #define M_NOTICE 0x010
544 #define M_WARNING 0x020
546 #define M_SECURITY 0x080
547 #define M_FATAL 0x100
549 /* The fatal() family of functions require messages that do not end in '\n' */
550 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
551 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
552 extern NORETURN(fatal_status(int status, const char *message, ...))
554 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
557 /* The cfgfatal() family of functions require messages that end in '\n' */
558 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
559 const char *message, ...)) FORMAT(printf,3,4);
560 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
561 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
562 cstring_t facility, const char *message,
565 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
567 const char *message, ...))
570 extern void Message(uint32_t class, const char *message, ...)
572 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
574 /***** END of log functions *****/
576 #define STRING2(x) #x
577 #define STRING(x) STRING2(x)
579 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
580 #define ARRAY_SIZE(ary) (sizeof((ary))/sizeof((ary)[0]))
583 * void COPY_OBJ( OBJECT& dst, const OBJECT& src);
584 * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
585 * // Typesafe: we check that the type OBJECT is the same in both cases.
586 * // It is OK to use COPY_OBJ on an array object, provided it's
587 * // _actually_ the whole array object and not decayed into a
588 * // pointer (e.g. a formal parameter).
590 #define COPY_OBJ(dst,src) \
591 (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
592 #define COPY_ARRAY(dst,src,count) \
593 (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
595 #endif /* secnet_h */