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 void childpersist_closefd_hook(void *fd_p, uint32_t newphase);
68 /* Convenience hook function for use with add_hook PHASE_CHILDPERSIST.
69 With `int fd' in your state struct, pass fd_p=&fd. The hook checks
70 whether fd>=0, so you can use it for an fd which is only sometimes
71 open. This function will set fd to -1, so it is idempotent. */
73 /***** CONFIGURATION support *****/
75 extern bool_t just_check_config; /* If True then we're going to exit after
76 reading the configuration file */
77 extern bool_t background; /* If True then we'll eventually run as a daemon */
79 typedef struct dict dict_t; /* Configuration dictionary */
80 typedef struct closure closure_t;
81 typedef struct item item_t;
82 typedef struct list list_t; /* A list of items */
84 /* Configuration file location, for error-reporting */
90 /* Modules export closures, which can be invoked from the configuration file.
91 "Invoking" a closure usually returns another closure (of a different
92 type), but can actually return any configuration object. */
93 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
94 dict_t *context, list_t *data);
96 cstring_t description; /* For debugging */
97 uint32_t type; /* Central registry... */
99 void *interface; /* Interface for use inside secnet; depends on type */
102 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
115 /* Note that it is unwise to use this structure directly; use the list
116 manipulation functions instead. */
122 /* In the following two lookup functions, NULL means 'not found' */
123 /* Lookup a value in the specified dictionary, or its parents */
124 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
125 /* Lookup a value in just the specified dictionary */
126 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
127 /* Add a value to the specified dictionary */
128 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
129 /* Obtain an array of keys in the dictionary. malloced; caller frees */
130 extern cstring_t *dict_keys(dict_t *dict);
132 /* List-manipulation functions */
133 extern list_t *list_new(void);
134 extern int32_t list_length(const list_t *a);
135 extern list_t *list_append(list_t *a, item_t *i);
136 extern list_t *list_append_list(list_t *a, list_t *b);
137 /* Returns an item from the list (index starts at 0), or NULL */
138 extern item_t *list_elem(list_t *l, int32_t index);
140 /* Convenience functions */
141 extern list_t *new_closure(closure_t *cl);
142 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
143 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
144 bool_t fail_if_invalid, cstring_t desc,
146 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
147 cstring_t desc, struct cloc loc);
148 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
149 cstring_t desc, struct cloc loc);
150 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
151 cstring_t desc, struct cloc loc,
153 /* return value can safely be assigned to int32_t */
154 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
155 cstring_t desc, struct cloc loc, bool_t def);
156 const char **dict_read_string_array(dict_t *dict, cstring_t key,
157 bool_t required, cstring_t desc,
158 struct cloc loc, const char *const *def);
159 /* Return value is a NULL-terminated array obtained from malloc;
160 * Individual string values are still owned by config file machinery
161 * and must not be modified or freed. Returns NULL if key not
168 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
169 struct flagstr *f, cstring_t desc);
170 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
173 /***** END of configuration support *****/
175 /***** UTILITY functions *****/
177 extern char *safe_strdup(const char *string, const char *message);
178 extern void *safe_malloc(size_t size, const char *message);
179 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
180 extern void *safe_realloc_ary(void *p, size_t size, size_t count,
181 const char *message);
183 void setcloexec(int fd); /* cannot fail */
184 void setnonblock(int fd); /* cannot fail */
185 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
187 extern int sys_cmd(const char *file, const char *argc, ...);
189 extern uint64_t now_global;
190 extern struct timeval tv_now_global;
192 static const uint64_t *const now = &now_global;
193 static const struct timeval *const tv_now = &tv_now_global;
195 /* "now" is current program time, in milliseconds. It is derived
196 from tv_now. Both are provided by the event loop. */
198 /***** END of utility functions *****/
200 /***** START of max_start_pad handling *****/
202 extern int32_t site_max_start_pad, transform_max_start_pad,
205 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
206 int32_t calculate_max_start_pad(void);
208 /***** END of max_start_pad handling *****/
210 /***** SCHEDULING support */
212 /* If nfds_io is insufficient for your needs, set it to the required
213 number and return ERANGE. timeout is in milliseconds; if it is too
214 high then lower it. It starts at -1 (==infinite). */
215 /* Note that beforepoll_fn may NOT do anything which might change the
216 fds or timeouts wanted by other registered poll loop loopers.
217 Callers should make sure of this by not making any calls into other
218 modules from the beforepoll_fn; the easiest way to ensure this is
219 for beforepoll_fn to only retreive information and not take any
222 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
224 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
225 /* If beforepoll_fn returned ERANGE, afterpoll_fn gets nfds==0.
226 afterpoll_fn never gets !!(fds[].revents & POLLNVAL) - such
227 a report is detected as a fatal error by the event loop. */
229 /* void BEFOREPOLL_WANT_FDS(int want);
230 * Expects: int *nfds_io;
231 * Can perform non-local exit.
232 * Checks whether there is space for want fds. If so, sets *nfds_io.
233 * If not, sets *nfds_io and returns. */
234 #define BEFOREPOLL_WANT_FDS(want) do{ \
235 if (*nfds_io<(want)) { *nfds_io=(want); return ERANGE; } \
239 /* Register interest in the main loop of the program. Before a call
240 to poll() your supplied beforepoll function will be called. After
241 the call to poll() the supplied afterpoll function will be called. */
242 struct poll_interest *register_for_poll(void *st, beforepoll_fn *before,
243 afterpoll_fn *after, cstring_t desc);
244 void deregister_for_poll(struct poll_interest *i);
246 /***** END of scheduling support */
248 /***** PROGRAM LIFETIME support */
250 /* The secnet program goes through a number of phases in its lifetime.
251 Module code may arrange to be called just as various phases are
254 Remember to update the table in util.c if changing the set of
259 PHASE_GETOPTS, /* Process command-line arguments */
260 PHASE_READCONFIG, /* Parse and process configuration file */
261 PHASE_SETUP, /* Process information in configuration */
262 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
263 PHASE_GETRESOURCES, /* Obtain all external resources */
264 PHASE_DROPPRIV, /* Last chance for privileged operations */
266 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
267 PHASE_CHILDPERSIST, /* Forked long-term child: close fds, etc. */
268 /* Keep this last: */
272 /* Each module should, in its CHILDPERSIST hooks, close all fds which
273 constitute ownership of important operating system resources, or
274 which are used for IPC with other processes who want to get the
275 usual disconnection effects if the main secnet process dies.
276 CHILDPERSIST hooks are not run if the child is going to exec;
277 so fds such as described above should be CLOEXEC too. */
279 typedef void hook_fn(void *self, uint32_t newphase);
280 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
281 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
283 extern uint32_t current_phase;
284 extern void enter_phase(uint32_t new_phase);
286 void phase_hooks_init(void); /* for main() only */
287 void clear_phase_hooks(uint32_t phase); /* for afterfork() */
289 /* Some features (like netlink 'soft' routes) require that secnet
290 retain root privileges. They should indicate that here when
292 extern bool_t require_root_privileges;
293 extern cstring_t require_root_privileges_explanation;
295 /* Some modules may want to know whether secnet is going to drop
296 privilege, so that they know whether to do privsep. Call only
297 in phases SETUP and later. */
298 bool_t will_droppriv(void);
300 /***** END of program lifetime support *****/
302 /***** MODULE support *****/
304 /* Module initialisation function type - modules export one function of
305 this type which is called to initialise them. For dynamically loaded
306 modules it's called "secnet_module". */
307 typedef void init_module(dict_t *dict);
309 extern void init_builtin_modules(dict_t *dict);
311 extern init_module resolver_module;
312 extern init_module random_module;
313 extern init_module udp_module;
314 extern init_module polypath_module;
315 extern init_module util_module;
316 extern init_module site_module;
317 extern init_module transform_eax_module;
318 extern init_module transform_cbcmac_module;
319 extern init_module netlink_module;
320 extern init_module rsa_module;
321 extern init_module dh_module;
322 extern init_module md5_module;
323 extern init_module slip_module;
324 extern init_module tun_module;
325 extern init_module sha1_module;
326 extern init_module log_module;
328 /***** END of module support *****/
330 /***** CLOSURE TYPES and interface definitions *****/
333 #define CL_RESOLVER 1
334 #define CL_RANDOMSRC 2
335 #define CL_RSAPUBKEY 3
336 #define CL_RSAPRIVKEY 4
341 #define CL_TRANSFORM 9
345 #define CL_NETLINK 14
349 /* PURE closure requires no interface */
351 /* RESOLVER interface */
353 /* Answers to queries are delivered to a function of this
354 type. 'address' will be NULL if there was a problem with the query. It
355 will be freed once resolve_answer_fn returns. naddrs is the actual
356 size of the array at addrs; was_naddrs is the number of addresses
357 actually found in the DNS, which may be bigger if addrs is equal
358 to MAX_PEER_ADDRS (ie there were too many). */
359 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
360 int naddrs, int was_naddrs,
361 const char *name, const char *failwhy);
362 /* name is the same ptr as passed to request, so its lifetime must
364 typedef bool_t resolve_request_fn(void *st, cstring_t name,
365 int remoteport, struct comm_if *comm,
366 resolve_answer_fn *cb, void *cst);
369 resolve_request_fn *request;
372 /* RANDOMSRC interface */
374 /* Return some random data. Returns TRUE for success. */
375 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
383 /* RSAPUBKEY interface */
385 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
386 cstring_t signature);
387 struct rsapubkey_if {
389 rsa_checksig_fn *check;
392 /* RSAPRIVKEY interface */
394 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
395 struct rsaprivkey_if {
397 rsa_makesig_fn *sign;
403 /* This struct is pure data; in particular comm's clients may
405 struct comm_if *comm;
407 int ix; /* see comment `Re comm_addr.ix' in udp.c */
410 /* Return True if the packet was processed, and shouldn't be passed to
411 any other potential receivers. (buf is freed iff True returned.) */
412 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
413 const struct comm_addr *source);
414 typedef void comm_request_notify_fn(void *commst, void *nst,
416 typedef void comm_release_notify_fn(void *commst, void *nst,
418 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
419 const struct comm_addr *dest);
420 /* Only returns false if (we know that) the local network
421 * environment is such that this address cannot work; transient
422 * or unknown/unexpected failures return true. */
423 typedef const char *comm_addr_to_string_fn(void *commst,
424 const struct comm_addr *ca);
425 /* Returned string is in a static buffer. */
428 comm_request_notify_fn *request_notify;
429 comm_release_notify_fn *release_notify;
430 comm_sendmsg_fn *sendmsg;
431 comm_addr_to_string_fn *addr_to_string;
434 bool_t iaddr_equal(const union iaddr *ia, const union iaddr *ib,
437 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
439 return ca->comm->addr_to_string(ca->comm->st, ca);
442 static inline bool_t comm_addr_equal(const struct comm_addr *a,
443 const struct comm_addr *b)
445 return a->comm==b->comm && iaddr_equal(&a->ia,&b->ia,False);
450 #define LOG_MESSAGE_BUFLEN 1023
452 typedef void log_msg_fn(void *st, int class, const char *message, ...);
453 typedef void log_vmsg_fn(void *st, int class, const char *message,
457 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
458 char buff[LOG_MESSAGE_BUFLEN+1];
460 /* (convenience functions, defined in util.c) */
461 extern void slilog(struct log_if *lf, int class, const char *message, ...)
463 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
466 /* Versions which take (parts of) (multiple) messages, using \n to
467 * distinguish one message from another. */
468 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
470 extern void vslilog_part(struct log_if *lf, int class, const char *message,
471 va_list) FORMAT(printf,3,0);
475 /* Pretty much a placeholder; allows starting and stopping of processing,
477 typedef void site_control_fn(void *st, bool_t run);
478 typedef uint32_t site_status_fn(void *st);
481 site_control_fn *control;
482 site_status_fn *status;
485 /* TRANSFORM interface */
487 /* A reversable transformation. Transforms buffer in-place; may add
488 data to start or end. (Reverse transformations decrease
489 length, of course.) Transformations may be key-dependent, in which
490 case key material is passed in at initialisation time. They may
491 also depend on internal factors (eg. time) and keep internal
492 state. A struct transform_if only represents a particular type of
493 transformation; instances of the transformation (eg. with
494 particular key material) have a different C type. The same
495 secret key will be used in opposite directions between a pair of
496 secnets; one of these pairs will get direction==False, the other True. */
498 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
499 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
501 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
502 typedef void transform_delkey_fn(void *st);
503 typedef void transform_destroyinstance_fn(void *st);
506 * 1: for any other problem
507 * 2: message decrypted but sequence number was out of range
509 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
510 const char **errmsg);
512 struct transform_inst_if {
514 transform_setkey_fn *setkey;
515 transform_valid_fn *valid;
516 transform_delkey_fn *delkey;
517 transform_apply_fn *forwards;
518 transform_apply_fn *reverse;
519 transform_destroyinstance_fn *destroy;
522 struct transform_if {
524 int capab_transformnum;
525 int32_t keylen; /* <<< INT_MAX */
526 transform_createinstance_fn *create;
529 /* NETLINK interface */
531 /* Used by netlink to deliver to site, and by site to deliver to
532 netlink. cid is the client identifier returned by
533 netlink_regnets_fn. If buf has size 0 then the function is just
534 being called for its site-effects (eg. making the site code attempt
535 to bring up a network link) */
536 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
537 /* site code can tell netlink when outgoing packets will be dropped,
538 so netlink can generate appropriate ICMP and make routing decisions */
539 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
540 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
541 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
542 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
543 #define LINK_QUALITY_UP 4 /* Link active */
544 #define MAXIMUM_LINK_QUALITY 3
545 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
546 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
547 void *dst, uint32_t *localmtu_r /* NULL ok */);
548 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
549 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
550 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
553 netlink_register_fn *reg;
554 netlink_deliver_fn *deliver;
555 netlink_link_quality_fn *set_quality;
556 netlink_set_mtu_fn *set_mtu;
561 /* Returns public key as a malloced hex string */
562 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
564 /* Fills buffer (up to buflen) with shared secret */
565 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
566 int32_t secretlen, cstring_t rempublic,
567 uint8_t *sharedsecret, int32_t buflen);
570 int32_t len; /* Approximate size of modulus in bytes */
571 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
572 dh_makepublic_fn *makepublic;
573 dh_makeshared_fn *makeshared;
578 typedef void *hash_init_fn(void);
579 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
580 typedef void hash_final_fn(void *st, uint8_t *digest);
582 int32_t len; /* Hash output length in bytes */
584 hash_update_fn *update;
585 hash_final_fn *final;
588 /* BUFFER interface */
592 cstring_t owner; /* Set to constant string */
593 uint32_t flags; /* How paranoid should we be? */
594 struct cloc loc; /* Where we were defined */
597 int32_t size; /* Size of buffer contents */
598 int32_t alloclen; /* Total length allocated at base */
601 /***** LOG functions *****/
603 #define M_DEBUG_CONFIG 0x001
604 #define M_DEBUG_PHASE 0x002
605 #define M_DEBUG 0x004
607 #define M_NOTICE 0x010
608 #define M_WARNING 0x020
610 #define M_SECURITY 0x080
611 #define M_FATAL 0x100
613 /* The fatal() family of functions require messages that do not end in '\n' */
614 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
615 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
616 extern NORETURN(fatal_status(int status, const char *message, ...))
618 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
621 /* Convenient nonfatal logging. Requires message that does not end in '\n'.
622 * If class contains M_FATAL, exits (after entering PHASE_SHUTDOWN).
623 * lg, errnoval and loc may sensibly be 0. desc must NOT be 0.
624 * lg_[v]perror save and restore errno. */
625 void lg_vperror(struct log_if *lg, const char *desc, struct cloc *loc,
626 int class, int errnoval, const char *fmt, va_list al)
628 void lg_perror(struct log_if *lg, const char *desc, struct cloc *loc,
629 int class, int errnoval, const char *fmt, ...)
631 void lg_exitstatus(struct log_if *lg, const char *desc, struct cloc *loc,
632 int class, int status, const char *progname);
634 /* The cfgfatal() family of functions require messages that end in '\n' */
635 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
636 const char *message, ...)) FORMAT(printf,3,4);
637 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
638 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
639 cstring_t facility, const char *message,
642 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
644 const char *message, ...))
647 extern void Message(uint32_t class, const char *message, ...)
649 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
651 /***** END of log functions *****/
653 #define STRING2(x) #x
654 #define STRING(x) STRING2(x)
656 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
657 #define ARRAY_SIZE(ary) (sizeof((ary))/sizeof((ary)[0]))
660 * void COPY_OBJ( OBJECT& dst, const OBJECT& src);
661 * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
662 * // Typesafe: we check that the type OBJECT is the same in both cases.
663 * // It is OK to use COPY_OBJ on an array object, provided it's
664 * // _actually_ the whole array object and not decayed into a
665 * // pointer (e.g. a formal parameter).
667 #define COPY_OBJ(dst,src) \
668 (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
669 #define COPY_ARRAY(dst,src,count) \
670 (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
672 #endif /* secnet_h */