1 /* Core interface of secnet, to be used by all modules */
15 #include <sys/types.h>
17 #include <netinet/in.h>
19 typedef char *string_t;
20 typedef const char *cstring_t;
22 #define False (_Bool)0
26 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
27 __FILE__,__LINE__); } } while(0)
31 extern char version[];
34 extern uint32_t message_level;
35 extern bool_t secnet_is_daemon;
36 extern struct log_if *system_log;
39 extern void start_signal_handling(void);
41 /***** CONFIGURATION support *****/
43 extern bool_t just_check_config; /* If True then we're going to exit after
44 reading the configuration file */
45 extern bool_t background; /* If True then we'll eventually run as a daemon */
47 typedef struct dict dict_t; /* Configuration dictionary */
48 typedef struct closure closure_t;
49 typedef struct item item_t;
50 typedef struct list list_t; /* A list of items */
52 /* Configuration file location, for error-reporting */
58 /* Modules export closures, which can be invoked from the configuration file.
59 "Invoking" a closure usually returns another closure (of a different
60 type), but can actually return any configuration object. */
61 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
62 dict_t *context, list_t *data);
64 cstring_t description; /* For debugging */
65 uint32_t type; /* Central registry... */
67 void *interface; /* Interface for use inside secnet; depends on type */
70 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
83 /* Note that it is unwise to use this structure directly; use the list
84 manipulation functions instead. */
90 /* In the following two lookup functions, NULL means 'not found' */
91 /* Lookup a value in the specified dictionary, or its parents */
92 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
93 /* Lookup a value in just the specified dictionary */
94 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
95 /* Add a value to the specified dictionary */
96 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
97 /* Obtain an array of keys in the dictionary. malloced; caller frees */
98 extern cstring_t *dict_keys(dict_t *dict);
100 /* List-manipulation functions */
101 extern list_t *list_new(void);
102 extern int32_t list_length(list_t *a);
103 extern list_t *list_append(list_t *a, item_t *i);
104 extern list_t *list_append_list(list_t *a, list_t *b);
105 /* Returns an item from the list (index starts at 0), or NULL */
106 extern item_t *list_elem(list_t *l, int32_t index);
108 /* Convenience functions */
109 extern list_t *new_closure(closure_t *cl);
110 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
111 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
112 bool_t fail_if_invalid, cstring_t desc,
114 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
115 cstring_t desc, struct cloc loc);
116 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
117 cstring_t desc, struct cloc loc);
118 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
119 cstring_t desc, struct cloc loc,
121 /* return value can safely be assigned to int32_t */
122 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
123 cstring_t desc, struct cloc loc, bool_t def);
128 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
129 struct flagstr *f, cstring_t desc);
130 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
133 /***** END of configuration support *****/
135 /***** UTILITY functions *****/
137 extern char *safe_strdup(const char *string, const char *message);
138 extern void *safe_malloc(size_t size, const char *message);
139 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
141 void setcloexec(int fd); /* cannot fail */
142 void pipe_cloexec(int fd[2]); /* pipe(), setcloexec() twice; cannot fail */
144 extern int sys_cmd(const char *file, const char *argc, ...);
146 extern uint64_t now_global;
147 extern struct timeval tv_now_global;
149 static const uint64_t *const now = &now_global;
150 static const struct timeval *const tv_now = &tv_now_global;
152 /* "now" is current program time, in milliseconds. It is derived
153 from tv_now. Both are provided by the event loop. */
155 /***** END of utility functions *****/
157 /***** START of max_start_pad handling *****/
159 extern int32_t site_max_start_pad, transform_max_start_pad,
162 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
163 int32_t calculate_max_start_pad(void);
165 /***** END of max_start_pad handling *****/
167 /***** SCHEDULING support */
169 /* If nfds_io is insufficient for your needs, set it to the required
170 number and return ERANGE. timeout is in milliseconds; if it is too
171 high then lower it. It starts at -1 (==infinite) */
172 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
174 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
176 /* Register interest in the main loop of the program. Before a call
177 to poll() your supplied beforepoll function will be called. After
178 the call to poll() the supplied afterpoll function will be called.
179 max_nfds is a _hint_ about the maximum number of struct pollfd
180 structures you may require - you can always ask for more in
182 extern void register_for_poll(void *st, beforepoll_fn *before,
183 afterpoll_fn *after, int32_t max_nfds,
186 /***** END of scheduling support */
188 /***** PROGRAM LIFETIME support */
190 /* The secnet program goes through a number of phases in its lifetime.
191 Module code may arrange to be called just as various phases are
194 Remember to update the table in util.c if changing the set of
199 PHASE_GETOPTS, /* Process command-line arguments */
200 PHASE_READCONFIG, /* Parse and process configuration file */
201 PHASE_SETUP, /* Process information in configuration */
202 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
203 PHASE_GETRESOURCES, /* Obtain all external resources */
204 PHASE_DROPPRIV, /* Last chance for privileged operations */
206 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
207 /* Keep this last: */
211 typedef void hook_fn(void *self, uint32_t newphase);
212 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
213 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
215 extern uint32_t current_phase;
216 extern void enter_phase(uint32_t new_phase);
218 /* Some features (like netlink 'soft' routes) require that secnet
219 retain root privileges. They should indicate that here when
221 extern bool_t require_root_privileges;
222 extern cstring_t require_root_privileges_explanation;
224 /***** END of program lifetime support *****/
226 /***** MODULE support *****/
228 /* Module initialisation function type - modules export one function of
229 this type which is called to initialise them. For dynamically loaded
230 modules it's called "secnet_module". */
231 typedef void init_module(dict_t *dict);
233 extern void init_builtin_modules(dict_t *dict);
235 extern init_module resolver_module;
236 extern init_module random_module;
237 extern init_module udp_module;
238 extern init_module util_module;
239 extern init_module site_module;
240 extern init_module transform_eax_module;
241 extern init_module transform_cbcmac_module;
242 extern init_module netlink_module;
243 extern init_module rsa_module;
244 extern init_module dh_module;
245 extern init_module md5_module;
246 extern init_module slip_module;
247 extern init_module tun_module;
248 extern init_module sha1_module;
249 extern init_module log_module;
251 /***** END of module support *****/
253 /***** CLOSURE TYPES and interface definitions *****/
256 #define CL_RESOLVER 1
257 #define CL_RANDOMSRC 2
258 #define CL_RSAPUBKEY 3
259 #define CL_RSAPRIVKEY 4
264 #define CL_TRANSFORM 9
268 #define CL_NETLINK 14
272 /* PURE closure requires no interface */
274 /* RESOLVER interface */
276 /* Answers to queries are delivered to a function of this
277 type. 'address' will be NULL if there was a problem with the query. It
278 will be freed once resolve_answer_fn returns. It is in network byte
280 /* XXX extend to be able to provide multiple answers */
281 typedef void resolve_answer_fn(void *st, struct in_addr *addr);
282 typedef bool_t resolve_request_fn(void *st, cstring_t name,
283 resolve_answer_fn *cb, void *cst);
286 resolve_request_fn *request;
289 /* RANDOMSRC interface */
291 /* Return some random data. Returns TRUE for success. */
292 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
300 /* RSAPUBKEY interface */
302 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
303 cstring_t signature);
304 struct rsapubkey_if {
306 rsa_checksig_fn *check;
309 /* RSAPRIVKEY interface */
311 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
312 struct rsaprivkey_if {
314 rsa_makesig_fn *sign;
320 /* This struct is pure data; in particular comm's clients may
322 /* Everyone is also guaranteed that all padding is set to zero, ie
323 that comm_addrs referring to semantically identical peers will
324 compare equal with memcmp. Anyone who constructs a comm_addr
325 must start by memsetting it with FILLZERO, or some
327 struct comm_if *comm;
328 struct sockaddr_in sin;
331 /* Return True if the packet was processed, and shouldn't be passed to
332 any other potential receivers. */
333 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
334 const struct comm_addr *source);
335 typedef void comm_request_notify_fn(void *commst, void *nst,
337 typedef void comm_release_notify_fn(void *commst, void *nst,
339 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
340 const struct comm_addr *dest);
341 /* Only returns false if (we know that) the local network
342 * environment is such that this address cannot work; transient
343 * or unknown/unexpected failures return true. */
344 typedef const char *comm_addr_to_string_fn(void *commst,
345 const struct comm_addr *ca);
346 /* Returned string is in a static buffer. */
349 comm_request_notify_fn *request_notify;
350 comm_release_notify_fn *release_notify;
351 comm_sendmsg_fn *sendmsg;
352 comm_addr_to_string_fn *addr_to_string;
355 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
357 return ca->comm->addr_to_string(ca->comm->st, ca);
362 #define LOG_MESSAGE_BUFLEN 1023
364 typedef void log_msg_fn(void *st, int class, const char *message, ...);
365 typedef void log_vmsg_fn(void *st, int class, const char *message,
369 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
370 char buff[LOG_MESSAGE_BUFLEN+1];
372 /* (convenience functions, defined in util.c) */
373 extern void slilog(struct log_if *lf, int class, const char *message, ...)
375 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
378 /* Versions which take (parts of) (multiple) messages, using \n to
379 * distinguish one message from another. */
380 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
382 extern void vslilog_part(struct log_if *lf, int class, const char *message,
383 va_list) FORMAT(printf,3,0);
387 /* Pretty much a placeholder; allows starting and stopping of processing,
389 typedef void site_control_fn(void *st, bool_t run);
390 typedef uint32_t site_status_fn(void *st);
393 site_control_fn *control;
394 site_status_fn *status;
397 /* TRANSFORM interface */
399 /* A reversable transformation. Transforms buffer in-place; may add
400 data to start or end. (Reverse transformations decrease
401 length, of course.) Transformations may be key-dependent, in which
402 case key material is passed in at initialisation time. They may
403 also depend on internal factors (eg. time) and keep internal
404 state. A struct transform_if only represents a particular type of
405 transformation; instances of the transformation (eg. with
406 particular key material) have a different C type. The same
407 secret key will be used in opposite directions between a pair of
408 secnets; one of these pairs will get direction==False, the other True. */
410 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
411 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
413 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
414 typedef void transform_delkey_fn(void *st);
415 typedef void transform_destroyinstance_fn(void *st);
418 * 1: for any other problem
419 * 2: message decrypted but sequence number was out of range
421 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
422 const char **errmsg);
424 struct transform_inst_if {
426 transform_setkey_fn *setkey;
427 transform_valid_fn *valid;
428 transform_delkey_fn *delkey;
429 transform_apply_fn *forwards;
430 transform_apply_fn *reverse;
431 transform_destroyinstance_fn *destroy;
434 struct transform_if {
436 int capab_transformnum;
437 int32_t keylen; /* <<< INT_MAX */
438 transform_createinstance_fn *create;
441 /* NETLINK interface */
443 /* Used by netlink to deliver to site, and by site to deliver to
444 netlink. cid is the client identifier returned by
445 netlink_regnets_fn. If buf has size 0 then the function is just
446 being called for its site-effects (eg. making the site code attempt
447 to bring up a network link) */
448 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
449 /* site code can tell netlink when outgoing packets will be dropped,
450 so netlink can generate appropriate ICMP and make routing decisions */
451 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
452 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
453 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
454 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
455 #define LINK_QUALITY_UP 4 /* Link active */
456 #define MAXIMUM_LINK_QUALITY 3
457 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
458 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
459 void *dst, uint32_t *localmtu_r /* NULL ok */);
460 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
461 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
462 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
465 netlink_register_fn *reg;
466 netlink_deliver_fn *deliver;
467 netlink_link_quality_fn *set_quality;
468 netlink_set_mtu_fn *set_mtu;
473 /* Returns public key as a malloced hex string */
474 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
476 /* Fills buffer (up to buflen) with shared secret */
477 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
478 int32_t secretlen, cstring_t rempublic,
479 uint8_t *sharedsecret, int32_t buflen);
482 int32_t len; /* Approximate size of modulus in bytes */
483 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
484 dh_makepublic_fn *makepublic;
485 dh_makeshared_fn *makeshared;
490 typedef void *hash_init_fn(void);
491 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
492 typedef void hash_final_fn(void *st, uint8_t *digest);
494 int32_t len; /* Hash output length in bytes */
496 hash_update_fn *update;
497 hash_final_fn *final;
500 /* BUFFER interface */
504 cstring_t owner; /* Set to constant string */
505 uint32_t flags; /* How paranoid should we be? */
506 struct cloc loc; /* Where we were defined */
509 int32_t size; /* Size of buffer contents */
510 int32_t alloclen; /* Total length allocated at base */
513 /***** LOG functions *****/
515 #define M_DEBUG_CONFIG 0x001
516 #define M_DEBUG_PHASE 0x002
517 #define M_DEBUG 0x004
519 #define M_NOTICE 0x010
520 #define M_WARNING 0x020
522 #define M_SECURITY 0x080
523 #define M_FATAL 0x100
525 /* The fatal() family of functions require messages that do not end in '\n' */
526 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
527 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
528 extern NORETURN(fatal_status(int status, const char *message, ...))
530 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
533 /* The cfgfatal() family of functions require messages that end in '\n' */
534 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
535 const char *message, ...)) FORMAT(printf,3,4);
536 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
537 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
538 cstring_t facility, const char *message,
541 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
543 const char *message, ...))
546 extern void Message(uint32_t class, const char *message, ...)
548 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
550 /***** END of log functions *****/
552 #define STRING2(x) #x
553 #define STRING(x) STRING2(x)
555 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
558 * void COPY_OBJ( OBJECT& dst, const OBJECT& src);
559 * void COPY_ARRAY(OBJECT *dst, const OBJECT *src, INTEGER count);
560 * // Typesafe: we check that the type OBJECT is the same in both cases.
561 * // It is OK to use COPY_OBJ on an array object, provided it's
562 * // _actually_ the whole array object and not decayed into a
563 * // pointer (e.g. a formal parameter).
565 #define COPY_OBJ(dst,src) \
566 (&(dst)==&(src), memcpy(&(dst),&(src),sizeof((dst))))
567 #define COPY_ARRAY(dst,src,count) \
568 (&(dst)[0]==&(src)[0], memcpy((dst),(src),sizeof((dst)[0])*(count)))
570 #endif /* secnet_h */