1 /* Core interface of secnet, to be used by all modules */
6 #define ADNS_FEATURE_MANYAF
19 #include <sys/types.h>
22 #include <netinet/in.h>
23 #include <arpa/inet.h>
25 #include <bsd/sys/queue.h>
27 #define MAX_PEER_ADDRS 5
28 /* send at most this many copies; honour at most that many addresses */
33 typedef char *string_t;
34 typedef const char *cstring_t;
36 #define False (_Bool)0
42 struct sockaddr_in sin;
44 struct sockaddr_in6 sin6;
48 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
49 __FILE__,__LINE__); } } while(0)
53 extern char version[];
56 extern uint32_t message_level;
57 extern bool_t secnet_is_daemon;
58 extern struct log_if *system_log;
61 extern void start_signal_handling(void);
64 /* Must be called before exec in every child made after
65 start_signal_handling. Safe to call in earlier children too. */
67 /***** CONFIGURATION support *****/
69 extern bool_t just_check_config; /* If True then we're going to exit after
70 reading the configuration file */
71 extern bool_t background; /* If True then we'll eventually run as a daemon */
73 typedef struct dict dict_t; /* Configuration dictionary */
74 typedef struct closure closure_t;
75 typedef struct item item_t;
76 typedef struct list list_t; /* A list of items */
78 /* Configuration file location, for error-reporting */
84 /* Modules export closures, which can be invoked from the configuration file.
85 "Invoking" a closure usually returns another closure (of a different
86 type), but can actually return any configuration object. */
87 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
88 dict_t *context, list_t *data);
90 cstring_t description; /* For debugging */
91 uint32_t type; /* Central registry... */
93 void *interface; /* Interface for use inside secnet; depends on type */
96 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
109 /* Note that it is unwise to use this structure directly; use the list
110 manipulation functions instead. */
116 /* In the following two lookup functions, NULL means 'not found' */
117 /* Lookup a value in the specified dictionary, or its parents */
118 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
119 /* Lookup a value in just the specified dictionary */
120 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
121 /* Add a value to the specified dictionary */
122 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
123 /* Obtain an array of keys in the dictionary. malloced; caller frees */
124 extern cstring_t *dict_keys(dict_t *dict);
126 /* List-manipulation functions */
127 extern list_t *list_new(void);
128 extern int32_t list_length(const list_t *a);
129 extern list_t *list_append(list_t *a, item_t *i);
130 extern list_t *list_append_list(list_t *a, list_t *b);
131 /* Returns an item from the list (index starts at 0), or NULL */
132 extern item_t *list_elem(list_t *l, int32_t index);
134 /* Convenience functions */
135 extern list_t *new_closure(closure_t *cl);
136 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
137 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
138 bool_t fail_if_invalid, cstring_t desc,
140 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
141 cstring_t desc, struct cloc loc);
142 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
143 cstring_t desc, struct cloc loc);
144 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
145 cstring_t desc, struct cloc loc,
147 /* return value can safely be assigned to int32_t */
148 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
149 cstring_t desc, struct cloc loc, bool_t def);
150 const char **dict_read_string_array(dict_t *dict, cstring_t key,
151 bool_t required, cstring_t desc,
152 struct cloc loc, const char *const *def);
153 /* Return value is a NULL-terminated array obtained from malloc;
154 * Individual string values are still owned by config file machinery
155 * and must not be modified or freed. Returns NULL if key not
162 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
163 struct flagstr *f, cstring_t desc);
164 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
167 /***** END of configuration support *****/
169 /***** UTILITY functions *****/
171 extern char *safe_strdup(const char *string, const char *message);
172 extern void *safe_malloc(size_t size, const char *message);
173 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
174 extern void *safe_realloc_ary(void *p, size_t size, size_t count,
175 const char *message);
177 void setcloexec(int fd); /* cannot fail */
178 void setnonblock(int fd); /* cannot fail */
179 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
181 extern int sys_cmd(const char *file, const char *argc, ...);
183 extern uint64_t now_global;
184 extern struct timeval tv_now_global;
186 static const uint64_t *const now = &now_global;
187 static const struct timeval *const tv_now = &tv_now_global;
189 /* "now" is current program time, in milliseconds. It is derived
190 from tv_now. Both are provided by the event loop. */
192 /***** END of utility functions *****/
194 /***** START of max_start_pad handling *****/
196 extern int32_t site_max_start_pad, transform_max_start_pad,
199 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
200 int32_t calculate_max_start_pad(void);
202 /***** END of max_start_pad handling *****/
204 /***** SCHEDULING support */
206 /* If nfds_io is insufficient for your needs, set it to the required
207 number and return ERANGE. timeout is in milliseconds; if it is too
208 high then lower it. It starts at -1 (==infinite). */
209 /* Note that beforepoll_fn may NOT do anything which might change the
210 fds or timeouts wanted by other registered poll loop loopers.
211 Callers should make sure of this by not making any calls into other
212 modules from the beforepoll_fn; the easiest way to ensure this is
213 for beforepoll_fn to only retreive information and not take any
216 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
218 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
219 /* If beforepoll_fn returned ERANGE, afterpoll_fn gets nfds==0.
220 afterpoll_fn never gets !!(fds[].revents & POLLNVAL) - such
221 a report is detected as a fatal error by the event loop. */
223 /* void BEFOREPOLL_WANT_FDS(int want);
224 * Expects: int *nfds_io;
225 * Can perform non-local exit.
226 * Checks whether there is space for want fds. If so, sets *nfds_io.
227 * If not, sets *nfds_io and returns. */
228 #define BEFOREPOLL_WANT_FDS(want) do{ \
229 if (*nfds_io<(want)) { *nfds_io=(want); return ERANGE; } \
233 /* Register interest in the main loop of the program. Before a call
234 to poll() your supplied beforepoll function will be called. After
235 the call to poll() the supplied afterpoll function will be called. */
236 struct poll_interest *register_for_poll(void *st, beforepoll_fn *before,
237 afterpoll_fn *after, cstring_t desc);
238 void deregister_for_poll(struct poll_interest *i);
240 /***** END of scheduling support */
242 /***** PROGRAM LIFETIME support */
244 /* The secnet program goes through a number of phases in its lifetime.
245 Module code may arrange to be called just as various phases are
248 Remember to update the table in util.c if changing the set of
253 PHASE_GETOPTS, /* Process command-line arguments */
254 PHASE_READCONFIG, /* Parse and process configuration file */
255 PHASE_SETUP, /* Process information in configuration */
256 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
257 PHASE_GETRESOURCES, /* Obtain all external resources */
258 PHASE_DROPPRIV, /* Last chance for privileged operations */
260 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
261 /* Keep this last: */
265 typedef void hook_fn(void *self, uint32_t newphase);
266 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
267 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
269 extern uint32_t current_phase;
270 extern void enter_phase(uint32_t new_phase);
272 void phase_hooks_init(void); /* for main() only */
274 /* Some features (like netlink 'soft' routes) require that secnet
275 retain root privileges. They should indicate that here when
277 extern bool_t require_root_privileges;
278 extern cstring_t require_root_privileges_explanation;
280 /* Some modules may want to know whether secnet is going to drop
281 privilege, so that they know whether to do privsep. Call only
282 in phases SETUP and later. */
283 bool_t will_droppriv(void);
285 /***** END of program lifetime support *****/
287 /***** MODULE support *****/
289 /* Module initialisation function type - modules export one function of
290 this type which is called to initialise them. For dynamically loaded
291 modules it's called "secnet_module". */
292 typedef void init_module(dict_t *dict);
294 extern void init_builtin_modules(dict_t *dict);
296 extern init_module resolver_module;
297 extern init_module random_module;
298 extern init_module udp_module;
299 extern init_module polypath_module;
300 extern init_module util_module;
301 extern init_module site_module;
302 extern init_module transform_eax_module;
303 extern init_module transform_cbcmac_module;
304 extern init_module netlink_module;
305 extern init_module rsa_module;
306 extern init_module dh_module;
307 extern init_module md5_module;
308 extern init_module slip_module;
309 extern init_module tun_module;
310 extern init_module sha1_module;
311 extern init_module log_module;
313 /***** END of module support *****/
315 /***** CLOSURE TYPES and interface definitions *****/
318 #define CL_RESOLVER 1
319 #define CL_RANDOMSRC 2
320 #define CL_RSAPUBKEY 3
321 #define CL_RSAPRIVKEY 4
326 #define CL_TRANSFORM 9
330 #define CL_NETLINK 14
334 /* PURE closure requires no interface */
336 /* RESOLVER interface */
338 /* Answers to queries are delivered to a function of this
339 type. 'address' will be NULL if there was a problem with the query. It
340 will be freed once resolve_answer_fn returns. naddrs is the actual
341 size of the array at addrs; was_naddrs is the number of addresses
342 actually found in the DNS, which may be bigger if addrs is equal
343 to MAX_PEER_ADDRS (ie there were too many). */
344 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
345 int naddrs, int was_naddrs,
346 const char *name, const char *failwhy);
347 /* name is the same ptr as passed to request, so its lifetime must
349 typedef bool_t resolve_request_fn(void *st, cstring_t name,
350 int remoteport, struct comm_if *comm,
351 resolve_answer_fn *cb, void *cst);
354 resolve_request_fn *request;
357 /* RANDOMSRC interface */
359 /* Return some random data. Returns TRUE for success. */
360 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
368 /* RSAPUBKEY interface */
370 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
371 cstring_t signature);
372 struct rsapubkey_if {
374 rsa_checksig_fn *check;
377 /* RSAPRIVKEY interface */
379 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
380 struct rsaprivkey_if {
382 rsa_makesig_fn *sign;
388 /* This struct is pure data; in particular comm's clients may
390 struct comm_if *comm;
392 int ix; /* see comment `Re comm_addr.ix' in udp.c */
395 /* Return True if the packet was processed, and shouldn't be passed to
396 any other potential receivers. (buf is freed iff True returned.) */
397 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
398 const struct comm_addr *source);
399 typedef void comm_request_notify_fn(void *commst, void *nst,
401 typedef void comm_release_notify_fn(void *commst, void *nst,
403 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
404 const struct comm_addr *dest);
405 /* Only returns false if (we know that) the local network
406 * environment is such that this address cannot work; transient
407 * or unknown/unexpected failures return true. */
408 typedef const char *comm_addr_to_string_fn(void *commst,
409 const struct comm_addr *ca);
410 /* Returned string is in a static buffer. */
413 comm_request_notify_fn *request_notify;
414 comm_release_notify_fn *release_notify;
415 comm_sendmsg_fn *sendmsg;
416 comm_addr_to_string_fn *addr_to_string;
419 bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib);
421 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
423 return ca->comm->addr_to_string(ca->comm->st, ca);
426 static inline bool_t comm_addr_equal(const struct comm_addr *a,
427 const struct comm_addr *b)
429 return a->comm==b->comm && iaddr_equal(&a->ia,&b->ia);
434 #define LOG_MESSAGE_BUFLEN 1023
436 typedef void log_msg_fn(void *st, int class, const char *message, ...);
437 typedef void log_vmsg_fn(void *st, int class, const char *message,
441 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
442 char buff[LOG_MESSAGE_BUFLEN+1];
444 /* (convenience functions, defined in util.c) */
445 extern void slilog(struct log_if *lf, int class, const char *message, ...)
447 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
450 /* Versions which take (parts of) (multiple) messages, using \n to
451 * distinguish one message from another. */
452 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
454 extern void vslilog_part(struct log_if *lf, int class, const char *message,
455 va_list) FORMAT(printf,3,0);
459 /* Pretty much a placeholder; allows starting and stopping of processing,
461 typedef void site_control_fn(void *st, bool_t run);
462 typedef uint32_t site_status_fn(void *st);
465 site_control_fn *control;
466 site_status_fn *status;
469 /* TRANSFORM interface */
471 /* A reversable transformation. Transforms buffer in-place; may add
472 data to start or end. (Reverse transformations decrease
473 length, of course.) Transformations may be key-dependent, in which
474 case key material is passed in at initialisation time. They may
475 also depend on internal factors (eg. time) and keep internal
476 state. A struct transform_if only represents a particular type of
477 transformation; instances of the transformation (eg. with
478 particular key material) have a different C type. The same
479 secret key will be used in opposite directions between a pair of
480 secnets; one of these pairs will get direction==False, the other True. */
482 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
483 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
485 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
486 typedef void transform_delkey_fn(void *st);
487 typedef void transform_destroyinstance_fn(void *st);
490 * 1: for any other problem
491 * 2: message decrypted but sequence number was out of range
493 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
494 const char **errmsg);
496 struct transform_inst_if {
498 transform_setkey_fn *setkey;
499 transform_valid_fn *valid;
500 transform_delkey_fn *delkey;
501 transform_apply_fn *forwards;
502 transform_apply_fn *reverse;
503 transform_destroyinstance_fn *destroy;
506 struct transform_if {
508 int capab_transformnum;
509 int32_t keylen; /* <<< INT_MAX */
510 transform_createinstance_fn *create;
513 /* NETLINK interface */
515 /* Used by netlink to deliver to site, and by site to deliver to
516 netlink. cid is the client identifier returned by
517 netlink_regnets_fn. If buf has size 0 then the function is just
518 being called for its site-effects (eg. making the site code attempt
519 to bring up a network link) */
520 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
521 /* site code can tell netlink when outgoing packets will be dropped,
522 so netlink can generate appropriate ICMP and make routing decisions */
523 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
524 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
525 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
526 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
527 #define LINK_QUALITY_UP 4 /* Link active */
528 #define MAXIMUM_LINK_QUALITY 3
529 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
530 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
531 void *dst, uint32_t *localmtu_r /* NULL ok */);
532 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
533 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
534 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
537 netlink_register_fn *reg;
538 netlink_deliver_fn *deliver;
539 netlink_link_quality_fn *set_quality;
540 netlink_set_mtu_fn *set_mtu;
545 /* Returns public key as a malloced hex string */
546 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
548 /* Fills buffer (up to buflen) with shared secret */
549 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
550 int32_t secretlen, cstring_t rempublic,
551 uint8_t *sharedsecret, int32_t buflen);
554 int32_t len; /* Approximate size of modulus in bytes */
555 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
556 dh_makepublic_fn *makepublic;
557 dh_makeshared_fn *makeshared;
562 typedef void *hash_init_fn(void);
563 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
564 typedef void hash_final_fn(void *st, uint8_t *digest);
566 int32_t len; /* Hash output length in bytes */
568 hash_update_fn *update;
569 hash_final_fn *final;
572 /* BUFFER interface */
576 cstring_t owner; /* Set to constant string */
577 uint32_t flags; /* How paranoid should we be? */
578 struct cloc loc; /* Where we were defined */
581 int32_t size; /* Size of buffer contents */
582 int32_t alloclen; /* Total length allocated at base */
585 /***** LOG functions *****/
587 #define M_DEBUG_CONFIG 0x001
588 #define M_DEBUG_PHASE 0x002
589 #define M_DEBUG 0x004
591 #define M_NOTICE 0x010
592 #define M_WARNING 0x020
594 #define M_SECURITY 0x080
595 #define M_FATAL 0x100
597 /* The fatal() family of functions require messages that do not end in '\n' */
598 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
599 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
600 extern NORETURN(fatal_status(int status, const char *message, ...))
602 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
605 /* Convenient nonfatal logging. Requires message that does not end in '\n'.
606 * If class contains M_FATAL, exits (after entering PHASE_SHUTDOWN).
607 * lg, errnoval and loc may sensibly be 0. desc must NOT be 0.
608 * lg_[v]perror save and restore errno. */
609 void lg_vperror(struct log_if *lg, const char *desc, struct cloc *loc,
610 int class, int errnoval, const char *fmt, va_list al)
612 void lg_perror(struct log_if *lg, const char *desc, struct cloc *loc,
613 int class, int errnoval, const char *fmt, ...)
615 void lg_exitstatus(struct log_if *lg, const char *desc, struct cloc *loc,
616 int class, int status, const char *progname);
618 /* The cfgfatal() family of functions require messages that end in '\n' */
619 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
620 const char *message, ...)) FORMAT(printf,3,4);
621 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
622 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
623 cstring_t facility, const char *message,
626 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
628 const char *message, ...))
631 extern void Message(uint32_t class, const char *message, ...)
633 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
635 /***** END of log functions *****/
637 #define STRING2(x) #x
638 #define STRING(x) STRING2(x)
640 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
641 #define ARRAY_SIZE(ary) (sizeof((ary))/sizeof((ary)[0]))
644 * void COPY_OBJ( OBJECT& dst, const OBJECT& src);
645 * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
646 * // Typesafe: we check that the type OBJECT is the same in both cases.
647 * // It is OK to use COPY_OBJ on an array object, provided it's
648 * // _actually_ the whole array object and not decayed into a
649 * // pointer (e.g. a formal parameter).
651 #define COPY_OBJ(dst,src) \
652 (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
653 #define COPY_ARRAY(dst,src,count) \
654 (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
656 #endif /* secnet_h */