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 #define MAX_PEER_ADDRS 5
23 /* send at most this many copies; honour at most that many addresses */
28 typedef char *string_t;
29 typedef const char *cstring_t;
31 #define False (_Bool)0
37 struct sockaddr_in sin;
39 struct sockaddr_in6 sin6;
43 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
44 __FILE__,__LINE__); } } while(0)
48 extern char version[];
51 extern uint32_t message_level;
52 extern bool_t secnet_is_daemon;
53 extern struct log_if *system_log;
56 extern void start_signal_handling(void);
58 /***** CONFIGURATION support *****/
60 extern bool_t just_check_config; /* If True then we're going to exit after
61 reading the configuration file */
62 extern bool_t background; /* If True then we'll eventually run as a daemon */
64 typedef struct dict dict_t; /* Configuration dictionary */
65 typedef struct closure closure_t;
66 typedef struct item item_t;
67 typedef struct list list_t; /* A list of items */
69 /* Configuration file location, for error-reporting */
75 /* Modules export closures, which can be invoked from the configuration file.
76 "Invoking" a closure usually returns another closure (of a different
77 type), but can actually return any configuration object. */
78 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
79 dict_t *context, list_t *data);
81 cstring_t description; /* For debugging */
82 uint32_t type; /* Central registry... */
84 void *interface; /* Interface for use inside secnet; depends on type */
87 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
100 /* Note that it is unwise to use this structure directly; use the list
101 manipulation functions instead. */
107 /* In the following two lookup functions, NULL means 'not found' */
108 /* Lookup a value in the specified dictionary, or its parents */
109 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
110 /* Lookup a value in just the specified dictionary */
111 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
112 /* Add a value to the specified dictionary */
113 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
114 /* Obtain an array of keys in the dictionary. malloced; caller frees */
115 extern cstring_t *dict_keys(dict_t *dict);
117 /* List-manipulation functions */
118 extern list_t *list_new(void);
119 extern int32_t list_length(const list_t *a);
120 extern list_t *list_append(list_t *a, item_t *i);
121 extern list_t *list_append_list(list_t *a, list_t *b);
122 /* Returns an item from the list (index starts at 0), or NULL */
123 extern item_t *list_elem(list_t *l, int32_t index);
125 /* Convenience functions */
126 extern list_t *new_closure(closure_t *cl);
127 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
128 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
129 bool_t fail_if_invalid, cstring_t desc,
131 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
132 cstring_t desc, struct cloc loc);
133 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
134 cstring_t desc, struct cloc loc);
135 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
136 cstring_t desc, struct cloc loc,
138 /* return value can safely be assigned to int32_t */
139 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
140 cstring_t desc, struct cloc loc, bool_t def);
141 const char **dict_read_string_array(dict_t *dict, cstring_t key,
142 bool_t required, cstring_t desc,
143 struct cloc loc, const char *const *def);
144 /* Return value is a NULL-terminated array obtained from malloc;
145 * Individual string values are still owned by config file machinery
146 * and must not be modified or freed. Returns NULL if key not
153 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
154 struct flagstr *f, cstring_t desc);
155 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
158 /***** END of configuration support *****/
160 /***** UTILITY functions *****/
162 extern char *safe_strdup(const char *string, const char *message);
163 extern void *safe_malloc(size_t size, const char *message);
164 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
166 void setcloexec(int fd); /* cannot fail */
167 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
169 extern int sys_cmd(const char *file, const char *argc, ...);
171 extern uint64_t now_global;
172 extern struct timeval tv_now_global;
174 static const uint64_t *const now = &now_global;
175 static const struct timeval *const tv_now = &tv_now_global;
177 /* "now" is current program time, in milliseconds. It is derived
178 from tv_now. Both are provided by the event loop. */
180 /***** END of utility functions *****/
182 /***** START of max_start_pad handling *****/
184 extern int32_t site_max_start_pad, transform_max_start_pad,
187 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
188 int32_t calculate_max_start_pad(void);
190 /***** END of max_start_pad handling *****/
192 /***** SCHEDULING support */
194 /* If nfds_io is insufficient for your needs, set it to the required
195 number and return ERANGE. timeout is in milliseconds; if it is too
196 high then lower it. It starts at -1 (==infinite) */
197 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
199 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
201 /* Register interest in the main loop of the program. Before a call
202 to poll() your supplied beforepoll function will be called. After
203 the call to poll() the supplied afterpoll function will be called.
204 max_nfds is a _hint_ about the maximum number of struct pollfd
205 structures you may require - you can always ask for more in
207 extern void register_for_poll(void *st, beforepoll_fn *before,
208 afterpoll_fn *after, int32_t max_nfds,
211 /***** END of scheduling support */
213 /***** PROGRAM LIFETIME support */
215 /* The secnet program goes through a number of phases in its lifetime.
216 Module code may arrange to be called just as various phases are
219 Remember to update the table in util.c if changing the set of
224 PHASE_GETOPTS, /* Process command-line arguments */
225 PHASE_READCONFIG, /* Parse and process configuration file */
226 PHASE_SETUP, /* Process information in configuration */
227 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
228 PHASE_GETRESOURCES, /* Obtain all external resources */
229 PHASE_DROPPRIV, /* Last chance for privileged operations */
231 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
232 /* Keep this last: */
236 typedef void hook_fn(void *self, uint32_t newphase);
237 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
238 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
240 extern uint32_t current_phase;
241 extern void enter_phase(uint32_t new_phase);
243 /* Some features (like netlink 'soft' routes) require that secnet
244 retain root privileges. They should indicate that here when
246 extern bool_t require_root_privileges;
247 extern cstring_t require_root_privileges_explanation;
249 /***** END of program lifetime support *****/
251 /***** MODULE support *****/
253 /* Module initialisation function type - modules export one function of
254 this type which is called to initialise them. For dynamically loaded
255 modules it's called "secnet_module". */
256 typedef void init_module(dict_t *dict);
258 extern void init_builtin_modules(dict_t *dict);
260 extern init_module resolver_module;
261 extern init_module random_module;
262 extern init_module udp_module;
263 extern init_module util_module;
264 extern init_module site_module;
265 extern init_module transform_eax_module;
266 extern init_module transform_cbcmac_module;
267 extern init_module netlink_module;
268 extern init_module rsa_module;
269 extern init_module dh_module;
270 extern init_module md5_module;
271 extern init_module slip_module;
272 extern init_module tun_module;
273 extern init_module sha1_module;
274 extern init_module log_module;
276 /***** END of module support *****/
278 /***** CLOSURE TYPES and interface definitions *****/
281 #define CL_RESOLVER 1
282 #define CL_RANDOMSRC 2
283 #define CL_RSAPUBKEY 3
284 #define CL_RSAPRIVKEY 4
289 #define CL_TRANSFORM 9
293 #define CL_NETLINK 14
297 /* PURE closure requires no interface */
299 /* RESOLVER interface */
301 /* Answers to queries are delivered to a function of this
302 type. 'address' will be NULL if there was a problem with the query. It
303 will be freed once resolve_answer_fn returns. It is in network byte
305 typedef void resolve_answer_fn(void *st, const struct comm_addr *addrs,
306 int naddrs, const char *name,
307 const char *failwhy);
308 /* name is the same ptr as passed to request, so its lifetime must
310 typedef bool_t resolve_request_fn(void *st, cstring_t name,
311 int remoteport, struct comm_if *comm,
312 resolve_answer_fn *cb, void *cst);
315 resolve_request_fn *request;
318 /* RANDOMSRC interface */
320 /* Return some random data. Returns TRUE for success. */
321 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
329 /* RSAPUBKEY interface */
331 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
332 cstring_t signature);
333 struct rsapubkey_if {
335 rsa_checksig_fn *check;
338 /* RSAPRIVKEY interface */
340 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
341 struct rsaprivkey_if {
343 rsa_makesig_fn *sign;
349 /* This struct is pure data; in particular comm's clients may
351 /* Everyone is also guaranteed that all padding is set to zero, ie
352 that comm_addrs referring to semantically identical peers will
353 compare equal with memcmp. Anyone who constructs a comm_addr
354 must start by memsetting it with FILLZERO, or some
356 struct comm_if *comm;
361 /* Return True if the packet was processed, and shouldn't be passed to
362 any other potential receivers. */
363 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
364 const struct comm_addr *source);
365 typedef void comm_request_notify_fn(void *commst, void *nst,
367 typedef void comm_release_notify_fn(void *commst, void *nst,
369 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
370 const struct comm_addr *dest);
371 /* Only returns false if (we know that) the local network
372 * environment is such that this address cannot work; transient
373 * or unknown/unexpected failures return true. */
374 typedef const char *comm_addr_to_string_fn(void *commst,
375 const struct comm_addr *ca);
376 /* Returned string is in a static buffer. */
379 comm_request_notify_fn *request_notify;
380 comm_release_notify_fn *release_notify;
381 comm_sendmsg_fn *sendmsg;
382 comm_addr_to_string_fn *addr_to_string;
385 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
387 return ca->comm->addr_to_string(ca->comm->st, ca);
392 #define LOG_MESSAGE_BUFLEN 1023
394 typedef void log_msg_fn(void *st, int class, const char *message, ...);
395 typedef void log_vmsg_fn(void *st, int class, const char *message,
399 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
400 char buff[LOG_MESSAGE_BUFLEN+1];
402 /* (convenience functions, defined in util.c) */
403 extern void slilog(struct log_if *lf, int class, const char *message, ...)
405 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
408 /* Versions which take (parts of) (multiple) messages, using \n to
409 * distinguish one message from another. */
410 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
412 extern void vslilog_part(struct log_if *lf, int class, const char *message,
413 va_list) FORMAT(printf,3,0);
417 /* Pretty much a placeholder; allows starting and stopping of processing,
419 typedef void site_control_fn(void *st, bool_t run);
420 typedef uint32_t site_status_fn(void *st);
423 site_control_fn *control;
424 site_status_fn *status;
427 /* TRANSFORM interface */
429 /* A reversable transformation. Transforms buffer in-place; may add
430 data to start or end. (Reverse transformations decrease
431 length, of course.) Transformations may be key-dependent, in which
432 case key material is passed in at initialisation time. They may
433 also depend on internal factors (eg. time) and keep internal
434 state. A struct transform_if only represents a particular type of
435 transformation; instances of the transformation (eg. with
436 particular key material) have a different C type. The same
437 secret key will be used in opposite directions between a pair of
438 secnets; one of these pairs will get direction==False, the other True. */
440 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
441 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
443 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
444 typedef void transform_delkey_fn(void *st);
445 typedef void transform_destroyinstance_fn(void *st);
448 * 1: for any other problem
449 * 2: message decrypted but sequence number was out of range
451 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
452 const char **errmsg);
454 struct transform_inst_if {
456 transform_setkey_fn *setkey;
457 transform_valid_fn *valid;
458 transform_delkey_fn *delkey;
459 transform_apply_fn *forwards;
460 transform_apply_fn *reverse;
461 transform_destroyinstance_fn *destroy;
464 struct transform_if {
466 int capab_transformnum;
467 int32_t keylen; /* <<< INT_MAX */
468 transform_createinstance_fn *create;
471 /* NETLINK interface */
473 /* Used by netlink to deliver to site, and by site to deliver to
474 netlink. cid is the client identifier returned by
475 netlink_regnets_fn. If buf has size 0 then the function is just
476 being called for its site-effects (eg. making the site code attempt
477 to bring up a network link) */
478 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
479 /* site code can tell netlink when outgoing packets will be dropped,
480 so netlink can generate appropriate ICMP and make routing decisions */
481 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
482 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
483 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
484 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
485 #define LINK_QUALITY_UP 4 /* Link active */
486 #define MAXIMUM_LINK_QUALITY 3
487 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
488 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
489 void *dst, uint32_t *localmtu_r /* NULL ok */);
490 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
491 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
492 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
495 netlink_register_fn *reg;
496 netlink_deliver_fn *deliver;
497 netlink_link_quality_fn *set_quality;
498 netlink_set_mtu_fn *set_mtu;
503 /* Returns public key as a malloced hex string */
504 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
506 /* Fills buffer (up to buflen) with shared secret */
507 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
508 int32_t secretlen, cstring_t rempublic,
509 uint8_t *sharedsecret, int32_t buflen);
512 int32_t len; /* Approximate size of modulus in bytes */
513 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
514 dh_makepublic_fn *makepublic;
515 dh_makeshared_fn *makeshared;
520 typedef void *hash_init_fn(void);
521 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
522 typedef void hash_final_fn(void *st, uint8_t *digest);
524 int32_t len; /* Hash output length in bytes */
526 hash_update_fn *update;
527 hash_final_fn *final;
530 /* BUFFER interface */
534 cstring_t owner; /* Set to constant string */
535 uint32_t flags; /* How paranoid should we be? */
536 struct cloc loc; /* Where we were defined */
539 int32_t size; /* Size of buffer contents */
540 int32_t alloclen; /* Total length allocated at base */
543 /***** LOG functions *****/
545 #define M_DEBUG_CONFIG 0x001
546 #define M_DEBUG_PHASE 0x002
547 #define M_DEBUG 0x004
549 #define M_NOTICE 0x010
550 #define M_WARNING 0x020
552 #define M_SECURITY 0x080
553 #define M_FATAL 0x100
555 /* The fatal() family of functions require messages that do not end in '\n' */
556 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
557 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
558 extern NORETURN(fatal_status(int status, const char *message, ...))
560 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
563 /* The cfgfatal() family of functions require messages that end in '\n' */
564 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
565 const char *message, ...)) FORMAT(printf,3,4);
566 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
567 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
568 cstring_t facility, const char *message,
571 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
573 const char *message, ...))
576 extern void Message(uint32_t class, const char *message, ...)
578 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
580 /***** END of log functions *****/
582 #define STRING2(x) #x
583 #define STRING(x) STRING2(x)
585 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
586 #define ARRAY_SIZE(ary) (sizeof(ary)/sizeof(ary[0]))
588 #endif /* secnet_h */