1 /* Core interface of secnet, to be used by all modules */
6 #define ADNS_FEATURE_MANYAF
18 #include <sys/types.h>
20 #include <netinet/in.h>
21 #include <arpa/inet.h>
23 #include <bsd/sys/queue.h>
25 #define MAX_PEER_ADDRS 5
26 /* send at most this many copies; honour at most that many addresses */
31 typedef char *string_t;
32 typedef const char *cstring_t;
34 #define False (_Bool)0
40 struct sockaddr_in sin;
42 struct sockaddr_in6 sin6;
46 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
47 __FILE__,__LINE__); } } while(0)
51 extern char version[];
54 extern uint32_t message_level;
55 extern bool_t secnet_is_daemon;
56 extern struct log_if *system_log;
59 extern void start_signal_handling(void);
61 /***** CONFIGURATION support *****/
63 extern bool_t just_check_config; /* If True then we're going to exit after
64 reading the configuration file */
65 extern bool_t background; /* If True then we'll eventually run as a daemon */
67 typedef struct dict dict_t; /* Configuration dictionary */
68 typedef struct closure closure_t;
69 typedef struct item item_t;
70 typedef struct list list_t; /* A list of items */
72 /* Configuration file location, for error-reporting */
78 /* Modules export closures, which can be invoked from the configuration file.
79 "Invoking" a closure usually returns another closure (of a different
80 type), but can actually return any configuration object. */
81 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
82 dict_t *context, list_t *data);
84 cstring_t description; /* For debugging */
85 uint32_t type; /* Central registry... */
87 void *interface; /* Interface for use inside secnet; depends on type */
90 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
103 /* Note that it is unwise to use this structure directly; use the list
104 manipulation functions instead. */
110 /* In the following two lookup functions, NULL means 'not found' */
111 /* Lookup a value in the specified dictionary, or its parents */
112 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
113 /* Lookup a value in just the specified dictionary */
114 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
115 /* Add a value to the specified dictionary */
116 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
117 /* Obtain an array of keys in the dictionary. malloced; caller frees */
118 extern cstring_t *dict_keys(dict_t *dict);
120 /* List-manipulation functions */
121 extern list_t *list_new(void);
122 extern int32_t list_length(const list_t *a);
123 extern list_t *list_append(list_t *a, item_t *i);
124 extern list_t *list_append_list(list_t *a, list_t *b);
125 /* Returns an item from the list (index starts at 0), or NULL */
126 extern item_t *list_elem(list_t *l, int32_t index);
128 /* Convenience functions */
129 extern list_t *new_closure(closure_t *cl);
130 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
131 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
132 bool_t fail_if_invalid, cstring_t desc,
134 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
135 cstring_t desc, struct cloc loc);
136 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
137 cstring_t desc, struct cloc loc);
138 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
139 cstring_t desc, struct cloc loc,
141 /* return value can safely be assigned to int32_t */
142 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
143 cstring_t desc, struct cloc loc, bool_t def);
144 const char **dict_read_string_array(dict_t *dict, cstring_t key,
145 bool_t required, cstring_t desc,
146 struct cloc loc, const char *const *def);
147 /* Return value is a NULL-terminated array obtained from malloc;
148 * Individual string values are still owned by config file machinery
149 * and must not be modified or freed. Returns NULL if key not
156 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
157 struct flagstr *f, cstring_t desc);
158 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
161 /***** END of configuration support *****/
163 /***** UTILITY functions *****/
165 extern char *safe_strdup(const char *string, const char *message);
166 extern void *safe_malloc(size_t size, const char *message);
167 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
169 void setcloexec(int fd); /* cannot fail */
170 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
172 extern int sys_cmd(const char *file, const char *argc, ...);
174 extern uint64_t now_global;
175 extern struct timeval tv_now_global;
177 static const uint64_t *const now = &now_global;
178 static const struct timeval *const tv_now = &tv_now_global;
180 /* "now" is current program time, in milliseconds. It is derived
181 from tv_now. Both are provided by the event loop. */
183 /***** END of utility functions *****/
185 /***** START of max_start_pad handling *****/
187 extern int32_t site_max_start_pad, transform_max_start_pad,
190 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
191 int32_t calculate_max_start_pad(void);
193 /***** END of max_start_pad handling *****/
195 /***** SCHEDULING support */
197 /* If nfds_io is insufficient for your needs, set it to the required
198 number and return ERANGE. timeout is in milliseconds; if it is too
199 high then lower it. It starts at -1 (==infinite) */
200 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
202 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
204 /* void BEFOREPOLL_WANT_FDS(int want);
205 * Expects: int *nfds_io;
206 * Can perform non-local exit.
207 * Checks whether there is space for want fds. If so, sets *nfds_io.
208 * If not, sets *nfds_io and returns. */
209 #define BEFOREPOLL_WANT_FDS(want) do{ \
210 if (*nfds_io<(want)) { *nfds_io=(want); return ERANGE; } \
214 /* Register interest in the main loop of the program. Before a call
215 to poll() your supplied beforepoll function will be called. After
216 the call to poll() the supplied afterpoll function will be called.
217 max_nfds is a _hint_ about the maximum number of struct pollfd
218 structures you may require - you can always ask for more in
220 extern void register_for_poll(void *st, beforepoll_fn *before,
221 afterpoll_fn *after, int32_t max_nfds,
224 /***** END of scheduling support */
226 /***** PROGRAM LIFETIME support */
228 /* The secnet program goes through a number of phases in its lifetime.
229 Module code may arrange to be called just as various phases are
232 Remember to update the table in util.c if changing the set of
237 PHASE_GETOPTS, /* Process command-line arguments */
238 PHASE_READCONFIG, /* Parse and process configuration file */
239 PHASE_SETUP, /* Process information in configuration */
240 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
241 PHASE_GETRESOURCES, /* Obtain all external resources */
242 PHASE_DROPPRIV, /* Last chance for privileged operations */
244 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
245 /* Keep this last: */
249 typedef void hook_fn(void *self, uint32_t newphase);
250 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
251 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
253 extern uint32_t current_phase;
254 extern void enter_phase(uint32_t new_phase);
256 /* Some features (like netlink 'soft' routes) require that secnet
257 retain root privileges. They should indicate that here when
259 extern bool_t require_root_privileges;
260 extern cstring_t require_root_privileges_explanation;
262 /***** END of program lifetime support *****/
264 /***** MODULE support *****/
266 /* Module initialisation function type - modules export one function of
267 this type which is called to initialise them. For dynamically loaded
268 modules it's called "secnet_module". */
269 typedef void init_module(dict_t *dict);
271 extern void init_builtin_modules(dict_t *dict);
273 extern init_module resolver_module;
274 extern init_module random_module;
275 extern init_module udp_module;
276 extern init_module util_module;
277 extern init_module site_module;
278 extern init_module transform_eax_module;
279 extern init_module transform_cbcmac_module;
280 extern init_module netlink_module;
281 extern init_module rsa_module;
282 extern init_module dh_module;
283 extern init_module md5_module;
284 extern init_module slip_module;
285 extern init_module tun_module;
286 extern init_module sha1_module;
287 extern init_module log_module;
289 /***** END of module support *****/
291 /***** CLOSURE TYPES and interface definitions *****/
294 #define CL_RESOLVER 1
295 #define CL_RANDOMSRC 2
296 #define CL_RSAPUBKEY 3
297 #define CL_RSAPRIVKEY 4
302 #define CL_TRANSFORM 9
306 #define CL_NETLINK 14
310 /* PURE closure requires no interface */
312 /* RESOLVER interface */
314 /* Answers to queries are delivered to a function of this
315 type. 'address' will be NULL if there was a problem with the query. It
316 will be freed once resolve_answer_fn returns. It is in network byte
318 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
319 int naddrs, const char *name,
320 const char *failwhy);
321 /* name is the same ptr as passed to request, so its lifetime must
323 typedef bool_t resolve_request_fn(void *st, cstring_t name,
324 int remoteport, struct comm_if *comm,
325 resolve_answer_fn *cb, void *cst);
328 resolve_request_fn *request;
331 /* RANDOMSRC interface */
333 /* Return some random data. Returns TRUE for success. */
334 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
342 /* RSAPUBKEY interface */
344 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
345 cstring_t signature);
346 struct rsapubkey_if {
348 rsa_checksig_fn *check;
351 /* RSAPRIVKEY interface */
353 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
354 struct rsaprivkey_if {
356 rsa_makesig_fn *sign;
362 /* This struct is pure data; in particular comm's clients may
364 /* Everyone is also guaranteed that all padding is set to zero, ie
365 that comm_addrs referring to semantically identical peers will
366 compare equal with memcmp. Anyone who constructs a comm_addr
367 must start by memsetting it with FILLZERO, or some
369 struct comm_if *comm;
374 /* Return True if the packet was processed, and shouldn't be passed to
375 any other potential receivers. */
376 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
377 const struct comm_addr *source);
378 typedef void comm_request_notify_fn(void *commst, void *nst,
380 typedef void comm_release_notify_fn(void *commst, void *nst,
382 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
383 const struct comm_addr *dest);
384 /* Only returns false if (we know that) the local network
385 * environment is such that this address cannot work; transient
386 * or unknown/unexpected failures return true. */
387 typedef const char *comm_addr_to_string_fn(void *commst,
388 const struct comm_addr *ca);
389 /* Returned string is in a static buffer. */
392 comm_request_notify_fn *request_notify;
393 comm_release_notify_fn *release_notify;
394 comm_sendmsg_fn *sendmsg;
395 comm_addr_to_string_fn *addr_to_string;
398 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
400 return ca->comm->addr_to_string(ca->comm->st, ca);
405 #define LOG_MESSAGE_BUFLEN 1023
407 typedef void log_msg_fn(void *st, int class, const char *message, ...);
408 typedef void log_vmsg_fn(void *st, int class, const char *message,
412 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
413 char buff[LOG_MESSAGE_BUFLEN+1];
415 /* (convenience functions, defined in util.c) */
416 extern void slilog(struct log_if *lf, int class, const char *message, ...)
418 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
421 /* Versions which take (parts of) (multiple) messages, using \n to
422 * distinguish one message from another. */
423 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
425 extern void vslilog_part(struct log_if *lf, int class, const char *message,
426 va_list) FORMAT(printf,3,0);
430 /* Pretty much a placeholder; allows starting and stopping of processing,
432 typedef void site_control_fn(void *st, bool_t run);
433 typedef uint32_t site_status_fn(void *st);
436 site_control_fn *control;
437 site_status_fn *status;
440 /* TRANSFORM interface */
442 /* A reversable transformation. Transforms buffer in-place; may add
443 data to start or end. (Reverse transformations decrease
444 length, of course.) Transformations may be key-dependent, in which
445 case key material is passed in at initialisation time. They may
446 also depend on internal factors (eg. time) and keep internal
447 state. A struct transform_if only represents a particular type of
448 transformation; instances of the transformation (eg. with
449 particular key material) have a different C type. The same
450 secret key will be used in opposite directions between a pair of
451 secnets; one of these pairs will get direction==False, the other True. */
453 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
454 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
456 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
457 typedef void transform_delkey_fn(void *st);
458 typedef void transform_destroyinstance_fn(void *st);
461 * 1: for any other problem
462 * 2: message decrypted but sequence number was out of range
464 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
465 const char **errmsg);
467 struct transform_inst_if {
469 transform_setkey_fn *setkey;
470 transform_valid_fn *valid;
471 transform_delkey_fn *delkey;
472 transform_apply_fn *forwards;
473 transform_apply_fn *reverse;
474 transform_destroyinstance_fn *destroy;
477 struct transform_if {
479 int capab_transformnum;
480 int32_t keylen; /* <<< INT_MAX */
481 transform_createinstance_fn *create;
484 /* NETLINK interface */
486 /* Used by netlink to deliver to site, and by site to deliver to
487 netlink. cid is the client identifier returned by
488 netlink_regnets_fn. If buf has size 0 then the function is just
489 being called for its site-effects (eg. making the site code attempt
490 to bring up a network link) */
491 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
492 /* site code can tell netlink when outgoing packets will be dropped,
493 so netlink can generate appropriate ICMP and make routing decisions */
494 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
495 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
496 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
497 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
498 #define LINK_QUALITY_UP 4 /* Link active */
499 #define MAXIMUM_LINK_QUALITY 3
500 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
501 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
502 void *dst, uint32_t *localmtu_r /* NULL ok */);
503 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
504 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
505 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
508 netlink_register_fn *reg;
509 netlink_deliver_fn *deliver;
510 netlink_link_quality_fn *set_quality;
511 netlink_set_mtu_fn *set_mtu;
516 /* Returns public key as a malloced hex string */
517 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
519 /* Fills buffer (up to buflen) with shared secret */
520 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
521 int32_t secretlen, cstring_t rempublic,
522 uint8_t *sharedsecret, int32_t buflen);
525 int32_t len; /* Approximate size of modulus in bytes */
526 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
527 dh_makepublic_fn *makepublic;
528 dh_makeshared_fn *makeshared;
533 typedef void *hash_init_fn(void);
534 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
535 typedef void hash_final_fn(void *st, uint8_t *digest);
537 int32_t len; /* Hash output length in bytes */
539 hash_update_fn *update;
540 hash_final_fn *final;
543 /* BUFFER interface */
547 cstring_t owner; /* Set to constant string */
548 uint32_t flags; /* How paranoid should we be? */
549 struct cloc loc; /* Where we were defined */
552 int32_t size; /* Size of buffer contents */
553 int32_t alloclen; /* Total length allocated at base */
556 /***** LOG functions *****/
558 #define M_DEBUG_CONFIG 0x001
559 #define M_DEBUG_PHASE 0x002
560 #define M_DEBUG 0x004
562 #define M_NOTICE 0x010
563 #define M_WARNING 0x020
565 #define M_SECURITY 0x080
566 #define M_FATAL 0x100
568 /* The fatal() family of functions require messages that do not end in '\n' */
569 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
570 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
571 extern NORETURN(fatal_status(int status, const char *message, ...))
573 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
576 /* The cfgfatal() family of functions require messages that end in '\n' */
577 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
578 const char *message, ...)) FORMAT(printf,3,4);
579 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
580 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
581 cstring_t facility, const char *message,
584 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
586 const char *message, ...))
589 extern void Message(uint32_t class, const char *message, ...)
591 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
593 /***** END of log functions *****/
595 #define STRING2(x) #x
596 #define STRING(x) STRING2(x)
598 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
599 #define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
601 #endif /* secnet_h */