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);
62 /***** CONFIGURATION support *****/
64 extern bool_t just_check_config; /* If True then we're going to exit after
65 reading the configuration file */
66 extern bool_t background; /* If True then we'll eventually run as a daemon */
68 typedef struct dict dict_t; /* Configuration dictionary */
69 typedef struct closure closure_t;
70 typedef struct item item_t;
71 typedef struct list list_t; /* A list of items */
73 /* Configuration file location, for error-reporting */
79 /* Modules export closures, which can be invoked from the configuration file.
80 "Invoking" a closure usually returns another closure (of a different
81 type), but can actually return any configuration object. */
82 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
83 dict_t *context, list_t *data);
85 cstring_t description; /* For debugging */
86 uint32_t type; /* Central registry... */
88 void *interface; /* Interface for use inside secnet; depends on type */
91 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
104 /* Note that it is unwise to use this structure directly; use the list
105 manipulation functions instead. */
111 /* In the following two lookup functions, NULL means 'not found' */
112 /* Lookup a value in the specified dictionary, or its parents */
113 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
114 /* Lookup a value in just the specified dictionary */
115 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
116 /* Add a value to the specified dictionary */
117 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
118 /* Obtain an array of keys in the dictionary. malloced; caller frees */
119 extern cstring_t *dict_keys(dict_t *dict);
121 /* List-manipulation functions */
122 extern list_t *list_new(void);
123 extern int32_t list_length(const list_t *a);
124 extern list_t *list_append(list_t *a, item_t *i);
125 extern list_t *list_append_list(list_t *a, list_t *b);
126 /* Returns an item from the list (index starts at 0), or NULL */
127 extern item_t *list_elem(list_t *l, int32_t index);
129 /* Convenience functions */
130 extern list_t *new_closure(closure_t *cl);
131 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
132 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
133 bool_t fail_if_invalid, cstring_t desc,
135 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
136 cstring_t desc, struct cloc loc);
137 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
138 cstring_t desc, struct cloc loc);
139 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
140 cstring_t desc, struct cloc loc,
142 /* return value can safely be assigned to int32_t */
143 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
144 cstring_t desc, struct cloc loc, bool_t def);
145 const char **dict_read_string_array(dict_t *dict, cstring_t key,
146 bool_t required, cstring_t desc,
147 struct cloc loc, const char *const *def);
148 /* Return value is a NULL-terminated array obtained from malloc;
149 * Individual string values are still owned by config file machinery
150 * and must not be modified or freed. Returns NULL if key not
157 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
158 struct flagstr *f, cstring_t desc);
159 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
162 /***** END of configuration support *****/
164 /***** UTILITY functions *****/
166 extern char *safe_strdup(const char *string, const char *message);
167 extern void *safe_malloc(size_t size, const char *message);
168 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
169 extern void *safe_realloc_ary(void *p, size_t size, size_t count,
170 const char *message);
172 void setcloexec(int fd); /* cannot fail */
173 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
175 extern int sys_cmd(const char *file, const char *argc, ...);
177 extern uint64_t now_global;
178 extern struct timeval tv_now_global;
180 static const uint64_t *const now = &now_global;
181 static const struct timeval *const tv_now = &tv_now_global;
183 /* "now" is current program time, in milliseconds. It is derived
184 from tv_now. Both are provided by the event loop. */
186 /***** END of utility functions *****/
188 /***** START of max_start_pad handling *****/
190 extern int32_t site_max_start_pad, transform_max_start_pad,
193 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
194 int32_t calculate_max_start_pad(void);
196 /***** END of max_start_pad handling *****/
198 /***** SCHEDULING support */
200 /* If nfds_io is insufficient for your needs, set it to the required
201 number and return ERANGE. timeout is in milliseconds; if it is too
202 high then lower it. It starts at -1 (==infinite). */
203 /* Note that beforepoll_fn may NOT do anything which might change the
204 fds or timeouts wanted by other registered poll loop loopers.
205 Callers should make sure of this by not making any calls into other
206 modules from the beforepoll_fn; the easiest way to ensure this is
207 for beforepoll_fn to only retreive information and not take any
210 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
212 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
214 /* void BEFOREPOLL_WANT_FDS(int want);
215 * Expects: int *nfds_io;
216 * Can perform non-local exit.
217 * Checks whether there is space for want fds. If so, sets *nfds_io.
218 * If not, sets *nfds_io and returns. */
219 #define BEFOREPOLL_WANT_FDS(want) do{ \
220 if (*nfds_io<(want)) { *nfds_io=(want); return ERANGE; } \
224 /* Register interest in the main loop of the program. Before a call
225 to poll() your supplied beforepoll function will be called. After
226 the call to poll() the supplied afterpoll function will be called. */
227 struct poll_interest *register_for_poll(void *st, beforepoll_fn *before,
228 afterpoll_fn *after, cstring_t desc);
229 void deregister_for_poll(struct poll_interest *i);
231 /***** END of scheduling support */
233 /***** PROGRAM LIFETIME support */
235 /* The secnet program goes through a number of phases in its lifetime.
236 Module code may arrange to be called just as various phases are
239 Remember to update the table in util.c if changing the set of
244 PHASE_GETOPTS, /* Process command-line arguments */
245 PHASE_READCONFIG, /* Parse and process configuration file */
246 PHASE_SETUP, /* Process information in configuration */
247 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
248 PHASE_GETRESOURCES, /* Obtain all external resources */
249 PHASE_DROPPRIV, /* Last chance for privileged operations */
251 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
252 /* Keep this last: */
256 typedef void hook_fn(void *self, uint32_t newphase);
257 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
258 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
260 extern uint32_t current_phase;
261 extern void enter_phase(uint32_t new_phase);
263 /* Some features (like netlink 'soft' routes) require that secnet
264 retain root privileges. They should indicate that here when
266 extern bool_t require_root_privileges;
267 extern cstring_t require_root_privileges_explanation;
269 /***** END of program lifetime support *****/
271 /***** MODULE support *****/
273 /* Module initialisation function type - modules export one function of
274 this type which is called to initialise them. For dynamically loaded
275 modules it's called "secnet_module". */
276 typedef void init_module(dict_t *dict);
278 extern void init_builtin_modules(dict_t *dict);
280 extern init_module resolver_module;
281 extern init_module random_module;
282 extern init_module udp_module;
283 extern init_module util_module;
284 extern init_module site_module;
285 extern init_module transform_eax_module;
286 extern init_module transform_cbcmac_module;
287 extern init_module netlink_module;
288 extern init_module rsa_module;
289 extern init_module dh_module;
290 extern init_module md5_module;
291 extern init_module slip_module;
292 extern init_module tun_module;
293 extern init_module sha1_module;
294 extern init_module log_module;
296 /***** END of module support *****/
298 /***** CLOSURE TYPES and interface definitions *****/
301 #define CL_RESOLVER 1
302 #define CL_RANDOMSRC 2
303 #define CL_RSAPUBKEY 3
304 #define CL_RSAPRIVKEY 4
309 #define CL_TRANSFORM 9
313 #define CL_NETLINK 14
317 /* PURE closure requires no interface */
319 /* RESOLVER interface */
321 /* Answers to queries are delivered to a function of this
322 type. 'address' will be NULL if there was a problem with the query. It
323 will be freed once resolve_answer_fn returns. It is in network byte
325 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
326 int naddrs, const char *name,
327 const char *failwhy);
328 /* name is the same ptr as passed to request, so its lifetime must
330 typedef bool_t resolve_request_fn(void *st, cstring_t name,
331 int remoteport, struct comm_if *comm,
332 resolve_answer_fn *cb, void *cst);
335 resolve_request_fn *request;
338 /* RANDOMSRC interface */
340 /* Return some random data. Returns TRUE for success. */
341 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
349 /* RSAPUBKEY interface */
351 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
352 cstring_t signature);
353 struct rsapubkey_if {
355 rsa_checksig_fn *check;
358 /* RSAPRIVKEY interface */
360 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
361 struct rsaprivkey_if {
363 rsa_makesig_fn *sign;
369 /* This struct is pure data; in particular comm's clients may
371 /* Everyone is also guaranteed that all padding is set to zero, ie
372 that comm_addrs referring to semantically identical peers will
373 compare equal with memcmp. Anyone who constructs a comm_addr
374 must start by memsetting it with FILLZERO, or some
376 struct comm_if *comm;
381 /* Return True if the packet was processed, and shouldn't be passed to
382 any other potential receivers. (buf is freed iff True returned.) */
383 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
384 const struct comm_addr *source);
385 typedef void comm_request_notify_fn(void *commst, void *nst,
387 typedef void comm_release_notify_fn(void *commst, void *nst,
389 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
390 const struct comm_addr *dest);
391 /* Only returns false if (we know that) the local network
392 * environment is such that this address cannot work; transient
393 * or unknown/unexpected failures return true. */
394 typedef const char *comm_addr_to_string_fn(void *commst,
395 const struct comm_addr *ca);
396 /* Returned string is in a static buffer. */
399 comm_request_notify_fn *request_notify;
400 comm_release_notify_fn *release_notify;
401 comm_sendmsg_fn *sendmsg;
402 comm_addr_to_string_fn *addr_to_string;
405 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
407 return ca->comm->addr_to_string(ca->comm->st, ca);
412 #define LOG_MESSAGE_BUFLEN 1023
414 typedef void log_msg_fn(void *st, int class, const char *message, ...);
415 typedef void log_vmsg_fn(void *st, int class, const char *message,
419 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
420 char buff[LOG_MESSAGE_BUFLEN+1];
422 /* (convenience functions, defined in util.c) */
423 extern void slilog(struct log_if *lf, int class, const char *message, ...)
425 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
428 /* Versions which take (parts of) (multiple) messages, using \n to
429 * distinguish one message from another. */
430 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
432 extern void vslilog_part(struct log_if *lf, int class, const char *message,
433 va_list) FORMAT(printf,3,0);
437 /* Pretty much a placeholder; allows starting and stopping of processing,
439 typedef void site_control_fn(void *st, bool_t run);
440 typedef uint32_t site_status_fn(void *st);
443 site_control_fn *control;
444 site_status_fn *status;
447 /* TRANSFORM interface */
449 /* A reversable transformation. Transforms buffer in-place; may add
450 data to start or end. (Reverse transformations decrease
451 length, of course.) Transformations may be key-dependent, in which
452 case key material is passed in at initialisation time. They may
453 also depend on internal factors (eg. time) and keep internal
454 state. A struct transform_if only represents a particular type of
455 transformation; instances of the transformation (eg. with
456 particular key material) have a different C type. The same
457 secret key will be used in opposite directions between a pair of
458 secnets; one of these pairs will get direction==False, the other True. */
460 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
461 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
463 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
464 typedef void transform_delkey_fn(void *st);
465 typedef void transform_destroyinstance_fn(void *st);
468 * 1: for any other problem
469 * 2: message decrypted but sequence number was out of range
471 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
472 const char **errmsg);
474 struct transform_inst_if {
476 transform_setkey_fn *setkey;
477 transform_valid_fn *valid;
478 transform_delkey_fn *delkey;
479 transform_apply_fn *forwards;
480 transform_apply_fn *reverse;
481 transform_destroyinstance_fn *destroy;
484 struct transform_if {
486 int capab_transformnum;
487 int32_t keylen; /* <<< INT_MAX */
488 transform_createinstance_fn *create;
491 /* NETLINK interface */
493 /* Used by netlink to deliver to site, and by site to deliver to
494 netlink. cid is the client identifier returned by
495 netlink_regnets_fn. If buf has size 0 then the function is just
496 being called for its site-effects (eg. making the site code attempt
497 to bring up a network link) */
498 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
499 /* site code can tell netlink when outgoing packets will be dropped,
500 so netlink can generate appropriate ICMP and make routing decisions */
501 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
502 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
503 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
504 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
505 #define LINK_QUALITY_UP 4 /* Link active */
506 #define MAXIMUM_LINK_QUALITY 3
507 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
508 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
509 void *dst, uint32_t *localmtu_r /* NULL ok */);
510 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
511 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
512 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
515 netlink_register_fn *reg;
516 netlink_deliver_fn *deliver;
517 netlink_link_quality_fn *set_quality;
518 netlink_set_mtu_fn *set_mtu;
523 /* Returns public key as a malloced hex string */
524 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
526 /* Fills buffer (up to buflen) with shared secret */
527 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
528 int32_t secretlen, cstring_t rempublic,
529 uint8_t *sharedsecret, int32_t buflen);
532 int32_t len; /* Approximate size of modulus in bytes */
533 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
534 dh_makepublic_fn *makepublic;
535 dh_makeshared_fn *makeshared;
540 typedef void *hash_init_fn(void);
541 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
542 typedef void hash_final_fn(void *st, uint8_t *digest);
544 int32_t len; /* Hash output length in bytes */
546 hash_update_fn *update;
547 hash_final_fn *final;
550 /* BUFFER interface */
554 cstring_t owner; /* Set to constant string */
555 uint32_t flags; /* How paranoid should we be? */
556 struct cloc loc; /* Where we were defined */
559 int32_t size; /* Size of buffer contents */
560 int32_t alloclen; /* Total length allocated at base */
563 /***** LOG functions *****/
565 #define M_DEBUG_CONFIG 0x001
566 #define M_DEBUG_PHASE 0x002
567 #define M_DEBUG 0x004
569 #define M_NOTICE 0x010
570 #define M_WARNING 0x020
572 #define M_SECURITY 0x080
573 #define M_FATAL 0x100
575 /* The fatal() family of functions require messages that do not end in '\n' */
576 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
577 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
578 extern NORETURN(fatal_status(int status, const char *message, ...))
580 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
583 /* Convenient nonfatal logging. Requires message that does not end in '\n'.
584 * If class contains M_FATAL, exits (after entering PHASE_SHUTDOWN).
585 * lg, errnoval and loc may sensibly be 0. desc must NOT be 0.
586 * lg_[v]perror save and restore errno. */
587 void lg_vperror(struct log_if *lg, const char *desc, struct cloc *loc,
588 int class, int errnoval, const char *fmt, va_list al)
590 void lg_perror(struct log_if *lg, const char *desc, struct cloc *loc,
591 int class, int errnoval, const char *fmt, ...)
593 void lg_exitstatus(struct log_if *lg, const char *desc, struct cloc *loc,
594 int class, int status, const char *progname);
596 /* The cfgfatal() family of functions require messages that end in '\n' */
597 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
598 const char *message, ...)) FORMAT(printf,3,4);
599 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
600 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
601 cstring_t facility, const char *message,
604 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
606 const char *message, ...))
609 extern void Message(uint32_t class, const char *message, ...)
611 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
613 /***** END of log functions *****/
615 #define STRING2(x) #x
616 #define STRING(x) STRING2(x)
618 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
619 #define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
621 #endif /* secnet_h */