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 #include <bsd/sys/queue.h>
24 #define MAX_PEER_ADDRS 5
25 /* send at most this many copies; honour at most that many addresses */
30 typedef char *string_t;
31 typedef const char *cstring_t;
33 #define False (_Bool)0
39 struct sockaddr_in sin;
41 struct sockaddr_in6 sin6;
45 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
46 __FILE__,__LINE__); } } while(0)
50 extern char version[];
53 extern uint32_t message_level;
54 extern bool_t secnet_is_daemon;
55 extern struct log_if *system_log;
58 extern void start_signal_handling(void);
60 /***** CONFIGURATION support *****/
62 extern bool_t just_check_config; /* If True then we're going to exit after
63 reading the configuration file */
64 extern bool_t background; /* If True then we'll eventually run as a daemon */
66 typedef struct dict dict_t; /* Configuration dictionary */
67 typedef struct closure closure_t;
68 typedef struct item item_t;
69 typedef struct list list_t; /* A list of items */
71 /* Configuration file location, for error-reporting */
77 /* Modules export closures, which can be invoked from the configuration file.
78 "Invoking" a closure usually returns another closure (of a different
79 type), but can actually return any configuration object. */
80 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
81 dict_t *context, list_t *data);
83 cstring_t description; /* For debugging */
84 uint32_t type; /* Central registry... */
86 void *interface; /* Interface for use inside secnet; depends on type */
89 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
102 /* Note that it is unwise to use this structure directly; use the list
103 manipulation functions instead. */
109 /* In the following two lookup functions, NULL means 'not found' */
110 /* Lookup a value in the specified dictionary, or its parents */
111 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
112 /* Lookup a value in just the specified dictionary */
113 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
114 /* Add a value to the specified dictionary */
115 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
116 /* Obtain an array of keys in the dictionary. malloced; caller frees */
117 extern cstring_t *dict_keys(dict_t *dict);
119 /* List-manipulation functions */
120 extern list_t *list_new(void);
121 extern int32_t list_length(const list_t *a);
122 extern list_t *list_append(list_t *a, item_t *i);
123 extern list_t *list_append_list(list_t *a, list_t *b);
124 /* Returns an item from the list (index starts at 0), or NULL */
125 extern item_t *list_elem(list_t *l, int32_t index);
127 /* Convenience functions */
128 extern list_t *new_closure(closure_t *cl);
129 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
130 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
131 bool_t fail_if_invalid, cstring_t desc,
133 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
134 cstring_t desc, struct cloc loc);
135 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
136 cstring_t desc, struct cloc loc);
137 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
138 cstring_t desc, struct cloc loc,
140 /* return value can safely be assigned to int32_t */
141 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
142 cstring_t desc, struct cloc loc, bool_t def);
143 const char **dict_read_string_array(dict_t *dict, cstring_t key,
144 bool_t required, cstring_t desc,
145 struct cloc loc, const char *const *def);
146 /* Return value is a NULL-terminated array obtained from malloc;
147 * Individual string values are still owned by config file machinery
148 * and must not be modified or freed. Returns NULL if key not
155 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
156 struct flagstr *f, cstring_t desc);
157 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
160 /***** END of configuration support *****/
162 /***** UTILITY functions *****/
164 extern char *safe_strdup(const char *string, const char *message);
165 extern void *safe_malloc(size_t size, const char *message);
166 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
168 void setcloexec(int fd); /* cannot fail */
169 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
171 extern int sys_cmd(const char *file, const char *argc, ...);
173 extern uint64_t now_global;
174 extern struct timeval tv_now_global;
176 static const uint64_t *const now = &now_global;
177 static const struct timeval *const tv_now = &tv_now_global;
179 /* "now" is current program time, in milliseconds. It is derived
180 from tv_now. Both are provided by the event loop. */
182 /***** END of utility functions *****/
184 /***** START of max_start_pad handling *****/
186 extern int32_t site_max_start_pad, transform_max_start_pad,
189 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
190 int32_t calculate_max_start_pad(void);
192 /***** END of max_start_pad handling *****/
194 /***** SCHEDULING support */
196 /* If nfds_io is insufficient for your needs, set it to the required
197 number and return ERANGE. timeout is in milliseconds; if it is too
198 high then lower it. It starts at -1 (==infinite) */
199 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
201 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
203 /* Register interest in the main loop of the program. Before a call
204 to poll() your supplied beforepoll function will be called. After
205 the call to poll() the supplied afterpoll function will be called.
206 max_nfds is a _hint_ about the maximum number of struct pollfd
207 structures you may require - you can always ask for more in
209 extern void register_for_poll(void *st, beforepoll_fn *before,
210 afterpoll_fn *after, int32_t max_nfds,
213 /***** END of scheduling support */
215 /***** PROGRAM LIFETIME support */
217 /* The secnet program goes through a number of phases in its lifetime.
218 Module code may arrange to be called just as various phases are
221 Remember to update the table in util.c if changing the set of
226 PHASE_GETOPTS, /* Process command-line arguments */
227 PHASE_READCONFIG, /* Parse and process configuration file */
228 PHASE_SETUP, /* Process information in configuration */
229 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
230 PHASE_GETRESOURCES, /* Obtain all external resources */
231 PHASE_DROPPRIV, /* Last chance for privileged operations */
233 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
234 /* Keep this last: */
238 typedef void hook_fn(void *self, uint32_t newphase);
239 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
240 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
242 extern uint32_t current_phase;
243 extern void enter_phase(uint32_t new_phase);
245 /* Some features (like netlink 'soft' routes) require that secnet
246 retain root privileges. They should indicate that here when
248 extern bool_t require_root_privileges;
249 extern cstring_t require_root_privileges_explanation;
251 /***** END of program lifetime support *****/
253 /***** MODULE support *****/
255 /* Module initialisation function type - modules export one function of
256 this type which is called to initialise them. For dynamically loaded
257 modules it's called "secnet_module". */
258 typedef void init_module(dict_t *dict);
260 extern void init_builtin_modules(dict_t *dict);
262 extern init_module resolver_module;
263 extern init_module random_module;
264 extern init_module udp_module;
265 extern init_module util_module;
266 extern init_module site_module;
267 extern init_module transform_eax_module;
268 extern init_module transform_cbcmac_module;
269 extern init_module netlink_module;
270 extern init_module rsa_module;
271 extern init_module dh_module;
272 extern init_module md5_module;
273 extern init_module slip_module;
274 extern init_module tun_module;
275 extern init_module sha1_module;
276 extern init_module log_module;
278 /***** END of module support *****/
280 /***** CLOSURE TYPES and interface definitions *****/
283 #define CL_RESOLVER 1
284 #define CL_RANDOMSRC 2
285 #define CL_RSAPUBKEY 3
286 #define CL_RSAPRIVKEY 4
291 #define CL_TRANSFORM 9
295 #define CL_NETLINK 14
299 /* PURE closure requires no interface */
301 /* RESOLVER interface */
303 /* Answers to queries are delivered to a function of this
304 type. 'address' will be NULL if there was a problem with the query. It
305 will be freed once resolve_answer_fn returns. It is in network byte
307 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
308 int naddrs, const char *name,
309 const char *failwhy);
310 /* name is the same ptr as passed to request, so its lifetime must
312 typedef bool_t resolve_request_fn(void *st, cstring_t name,
313 int remoteport, struct comm_if *comm,
314 resolve_answer_fn *cb, void *cst);
317 resolve_request_fn *request;
320 /* RANDOMSRC interface */
322 /* Return some random data. Returns TRUE for success. */
323 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
331 /* RSAPUBKEY interface */
333 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
334 cstring_t signature);
335 struct rsapubkey_if {
337 rsa_checksig_fn *check;
340 /* RSAPRIVKEY interface */
342 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
343 struct rsaprivkey_if {
345 rsa_makesig_fn *sign;
351 /* This struct is pure data; in particular comm's clients may
353 /* Everyone is also guaranteed that all padding is set to zero, ie
354 that comm_addrs referring to semantically identical peers will
355 compare equal with memcmp. Anyone who constructs a comm_addr
356 must start by memsetting it with FILLZERO, or some
358 struct comm_if *comm;
363 /* Return True if the packet was processed, and shouldn't be passed to
364 any other potential receivers. */
365 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
366 const struct comm_addr *source);
367 typedef void comm_request_notify_fn(void *commst, void *nst,
369 typedef void comm_release_notify_fn(void *commst, void *nst,
371 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
372 const struct comm_addr *dest);
373 /* Only returns false if (we know that) the local network
374 * environment is such that this address cannot work; transient
375 * or unknown/unexpected failures return true. */
376 typedef const char *comm_addr_to_string_fn(void *commst,
377 const struct comm_addr *ca);
378 /* Returned string is in a static buffer. */
381 comm_request_notify_fn *request_notify;
382 comm_release_notify_fn *release_notify;
383 comm_sendmsg_fn *sendmsg;
384 comm_addr_to_string_fn *addr_to_string;
387 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
389 return ca->comm->addr_to_string(ca->comm->st, ca);
394 #define LOG_MESSAGE_BUFLEN 1023
396 typedef void log_msg_fn(void *st, int class, const char *message, ...);
397 typedef void log_vmsg_fn(void *st, int class, const char *message,
401 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
402 char buff[LOG_MESSAGE_BUFLEN+1];
404 /* (convenience functions, defined in util.c) */
405 extern void slilog(struct log_if *lf, int class, const char *message, ...)
407 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
410 /* Versions which take (parts of) (multiple) messages, using \n to
411 * distinguish one message from another. */
412 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
414 extern void vslilog_part(struct log_if *lf, int class, const char *message,
415 va_list) FORMAT(printf,3,0);
419 /* Pretty much a placeholder; allows starting and stopping of processing,
421 typedef void site_control_fn(void *st, bool_t run);
422 typedef uint32_t site_status_fn(void *st);
425 site_control_fn *control;
426 site_status_fn *status;
429 /* TRANSFORM interface */
431 /* A reversable transformation. Transforms buffer in-place; may add
432 data to start or end. (Reverse transformations decrease
433 length, of course.) Transformations may be key-dependent, in which
434 case key material is passed in at initialisation time. They may
435 also depend on internal factors (eg. time) and keep internal
436 state. A struct transform_if only represents a particular type of
437 transformation; instances of the transformation (eg. with
438 particular key material) have a different C type. The same
439 secret key will be used in opposite directions between a pair of
440 secnets; one of these pairs will get direction==False, the other True. */
442 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
443 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
445 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
446 typedef void transform_delkey_fn(void *st);
447 typedef void transform_destroyinstance_fn(void *st);
450 * 1: for any other problem
451 * 2: message decrypted but sequence number was out of range
453 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
454 const char **errmsg);
456 struct transform_inst_if {
458 transform_setkey_fn *setkey;
459 transform_valid_fn *valid;
460 transform_delkey_fn *delkey;
461 transform_apply_fn *forwards;
462 transform_apply_fn *reverse;
463 transform_destroyinstance_fn *destroy;
466 struct transform_if {
468 int capab_transformnum;
469 int32_t keylen; /* <<< INT_MAX */
470 transform_createinstance_fn *create;
473 /* NETLINK interface */
475 /* Used by netlink to deliver to site, and by site to deliver to
476 netlink. cid is the client identifier returned by
477 netlink_regnets_fn. If buf has size 0 then the function is just
478 being called for its site-effects (eg. making the site code attempt
479 to bring up a network link) */
480 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
481 /* site code can tell netlink when outgoing packets will be dropped,
482 so netlink can generate appropriate ICMP and make routing decisions */
483 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
484 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
485 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
486 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
487 #define LINK_QUALITY_UP 4 /* Link active */
488 #define MAXIMUM_LINK_QUALITY 3
489 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
490 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
491 void *dst, uint32_t *localmtu_r /* NULL ok */);
492 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
493 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
494 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
497 netlink_register_fn *reg;
498 netlink_deliver_fn *deliver;
499 netlink_link_quality_fn *set_quality;
500 netlink_set_mtu_fn *set_mtu;
505 /* Returns public key as a malloced hex string */
506 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
508 /* Fills buffer (up to buflen) with shared secret */
509 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
510 int32_t secretlen, cstring_t rempublic,
511 uint8_t *sharedsecret, int32_t buflen);
514 int32_t len; /* Approximate size of modulus in bytes */
515 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
516 dh_makepublic_fn *makepublic;
517 dh_makeshared_fn *makeshared;
522 typedef void *hash_init_fn(void);
523 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
524 typedef void hash_final_fn(void *st, uint8_t *digest);
526 int32_t len; /* Hash output length in bytes */
528 hash_update_fn *update;
529 hash_final_fn *final;
532 /* BUFFER interface */
536 cstring_t owner; /* Set to constant string */
537 uint32_t flags; /* How paranoid should we be? */
538 struct cloc loc; /* Where we were defined */
541 int32_t size; /* Size of buffer contents */
542 int32_t alloclen; /* Total length allocated at base */
545 /***** LOG functions *****/
547 #define M_DEBUG_CONFIG 0x001
548 #define M_DEBUG_PHASE 0x002
549 #define M_DEBUG 0x004
551 #define M_NOTICE 0x010
552 #define M_WARNING 0x020
554 #define M_SECURITY 0x080
555 #define M_FATAL 0x100
557 /* The fatal() family of functions require messages that do not end in '\n' */
558 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
559 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
560 extern NORETURN(fatal_status(int status, const char *message, ...))
562 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
565 /* The cfgfatal() family of functions require messages that end in '\n' */
566 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
567 const char *message, ...)) FORMAT(printf,3,4);
568 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
569 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
570 cstring_t facility, const char *message,
573 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
575 const char *message, ...))
578 extern void Message(uint32_t class, const char *message, ...)
580 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
582 /***** END of log functions *****/
584 #define STRING2(x) #x
585 #define STRING(x) STRING2(x)
587 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
588 #define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
590 #endif /* secnet_h */