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 */
143 extern int sys_cmd(const char *file, const char *argc, ...);
145 extern uint64_t now_global;
146 extern struct timeval tv_now_global;
148 static const uint64_t *const now = &now_global;
149 static const struct timeval *const tv_now = &tv_now_global;
151 /* "now" is current program time, in milliseconds. It is derived
152 from tv_now. Both are provided by the event loop. */
154 /***** END of utility functions *****/
156 /***** START of max_start_pad handling *****/
158 extern int32_t site_max_start_pad, transform_max_start_pad,
161 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
162 int32_t calculate_max_start_pad(void);
164 /***** END of max_start_pad handling *****/
166 /***** SCHEDULING support */
168 /* If nfds_io is insufficient for your needs, set it to the required
169 number and return ERANGE. timeout is in milliseconds; if it is too
170 high then lower it. It starts at -1 (==infinite) */
171 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
173 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
175 /* Register interest in the main loop of the program. Before a call
176 to poll() your supplied beforepoll function will be called. After
177 the call to poll() the supplied afterpoll function will be called.
178 max_nfds is a _hint_ about the maximum number of struct pollfd
179 structures you may require - you can always ask for more in
181 extern void register_for_poll(void *st, beforepoll_fn *before,
182 afterpoll_fn *after, int32_t max_nfds,
185 /***** END of scheduling support */
187 /***** PROGRAM LIFETIME support */
189 /* The secnet program goes through a number of phases in its lifetime.
190 Module code may arrange to be called just as various phases are
193 Remember to update the table in util.c if changing the set of
198 PHASE_GETOPTS, /* Process command-line arguments */
199 PHASE_READCONFIG, /* Parse and process configuration file */
200 PHASE_SETUP, /* Process information in configuration */
201 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
202 PHASE_GETRESOURCES, /* Obtain all external resources */
203 PHASE_DROPPRIV, /* Last chance for privileged operations */
205 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
206 /* Keep this last: */
210 typedef void hook_fn(void *self, uint32_t newphase);
211 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
212 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
214 extern uint32_t current_phase;
215 extern void enter_phase(uint32_t new_phase);
217 /* Some features (like netlink 'soft' routes) require that secnet
218 retain root privileges. They should indicate that here when
220 extern bool_t require_root_privileges;
221 extern cstring_t require_root_privileges_explanation;
223 /***** END of program lifetime support *****/
225 /***** MODULE support *****/
227 /* Module initialisation function type - modules export one function of
228 this type which is called to initialise them. For dynamically loaded
229 modules it's called "secnet_module". */
230 typedef void init_module(dict_t *dict);
232 extern void init_builtin_modules(dict_t *dict);
234 extern init_module resolver_module;
235 extern init_module random_module;
236 extern init_module udp_module;
237 extern init_module util_module;
238 extern init_module site_module;
239 extern init_module transform_eax_module;
240 extern init_module transform_cbcmac_module;
241 extern init_module netlink_module;
242 extern init_module rsa_module;
243 extern init_module dh_module;
244 extern init_module md5_module;
245 extern init_module slip_module;
246 extern init_module tun_module;
247 extern init_module sha1_module;
248 extern init_module log_module;
250 /***** END of module support *****/
252 /***** CLOSURE TYPES and interface definitions *****/
255 #define CL_RESOLVER 1
256 #define CL_RANDOMSRC 2
257 #define CL_RSAPUBKEY 3
258 #define CL_RSAPRIVKEY 4
263 #define CL_TRANSFORM 9
267 #define CL_NETLINK 14
271 /* PURE closure requires no interface */
273 /* RESOLVER interface */
275 /* Answers to queries are delivered to a function of this
276 type. 'address' will be NULL if there was a problem with the query. It
277 will be freed once resolve_answer_fn returns. It is in network byte
279 /* XXX extend to be able to provide multiple answers */
280 typedef void resolve_answer_fn(void *st, struct in_addr *addr);
281 typedef bool_t resolve_request_fn(void *st, cstring_t name,
282 resolve_answer_fn *cb, void *cst);
285 resolve_request_fn *request;
288 /* RANDOMSRC interface */
290 /* Return some random data. Returns TRUE for success. */
291 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
299 /* RSAPUBKEY interface */
301 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
302 cstring_t signature);
303 struct rsapubkey_if {
305 rsa_checksig_fn *check;
308 /* RSAPRIVKEY interface */
310 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
311 struct rsaprivkey_if {
313 rsa_makesig_fn *sign;
319 /* This struct is pure data; in particular comm's clients may
321 /* Everyone is also guaranteed that all padding is set to zero, ie
322 that comm_addrs referring to semantically identical peers will
323 compare equal with memcmp. Anyone who constructs a comm_addr
324 must start by memsetting it with FILLZERO, or some
326 struct comm_if *comm;
327 struct sockaddr_in sin;
330 /* Return True if the packet was processed, and shouldn't be passed to
331 any other potential receivers. */
332 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
333 const struct comm_addr *source);
334 typedef void comm_request_notify_fn(void *commst, void *nst,
336 typedef void comm_release_notify_fn(void *commst, void *nst,
338 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
339 const struct comm_addr *dest);
340 typedef const char *comm_addr_to_string_fn(void *commst,
341 const struct comm_addr *ca);
342 /* Returned string is in a static buffer. */
345 comm_request_notify_fn *request_notify;
346 comm_release_notify_fn *release_notify;
347 comm_sendmsg_fn *sendmsg;
348 comm_addr_to_string_fn *addr_to_string;
351 static inline const char *comm_addr_to_string(const struct comm_addr *ca)
353 return ca->comm->addr_to_string(ca->comm->st, ca);
358 #define LOG_MESSAGE_BUFLEN 1023
360 typedef void log_msg_fn(void *st, int class, const char *message, ...);
361 typedef void log_vmsg_fn(void *st, int class, const char *message,
365 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
366 char buff[LOG_MESSAGE_BUFLEN+1];
368 /* (convenience functions, defined in util.c) */
369 extern void slilog(struct log_if *lf, int class, const char *message, ...)
371 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
374 /* Versions which take (parts of) (multiple) messages, using \n to
375 * distinguish one message from another. */
376 extern void slilog_part(struct log_if *lf, int class, const char *message, ...)
378 extern void vslilog_part(struct log_if *lf, int class, const char *message,
379 va_list) FORMAT(printf,3,0);
383 /* Pretty much a placeholder; allows starting and stopping of processing,
385 typedef void site_control_fn(void *st, bool_t run);
386 typedef uint32_t site_status_fn(void *st);
389 site_control_fn *control;
390 site_status_fn *status;
393 /* TRANSFORM interface */
395 /* A reversable transformation. Transforms buffer in-place; may add
396 data to start or end. (Reverse transformations decrease
397 length, of course.) Transformations may be key-dependent, in which
398 case key material is passed in at initialisation time. They may
399 also depend on internal factors (eg. time) and keep internal
400 state. A struct transform_if only represents a particular type of
401 transformation; instances of the transformation (eg. with
402 particular key material) have a different C type. The same
403 secret key will be used in opposite directions between a pair of
404 secnets; one of these pairs will get direction==False, the other True. */
406 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
407 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
409 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
410 typedef void transform_delkey_fn(void *st);
411 typedef void transform_destroyinstance_fn(void *st);
414 * 1: for any other problem
415 * 2: message decrypted but sequence number was out of range
417 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
418 const char **errmsg);
420 struct transform_inst_if {
422 transform_setkey_fn *setkey;
423 transform_valid_fn *valid;
424 transform_delkey_fn *delkey;
425 transform_apply_fn *forwards;
426 transform_apply_fn *reverse;
427 transform_destroyinstance_fn *destroy;
430 struct transform_if {
432 int capab_transformnum;
433 int32_t keylen; /* <<< INT_MAX */
434 transform_createinstance_fn *create;
437 /* NETLINK interface */
439 /* Used by netlink to deliver to site, and by site to deliver to
440 netlink. cid is the client identifier returned by
441 netlink_regnets_fn. If buf has size 0 then the function is just
442 being called for its site-effects (eg. making the site code attempt
443 to bring up a network link) */
444 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
445 /* site code can tell netlink when outgoing packets will be dropped,
446 so netlink can generate appropriate ICMP and make routing decisions */
447 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
448 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
449 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
450 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
451 #define LINK_QUALITY_UP 4 /* Link active */
452 #define MAXIMUM_LINK_QUALITY 3
453 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
454 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
455 void *dst, uint32_t *localmtu_r /* NULL ok */);
456 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
457 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
458 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
461 netlink_register_fn *reg;
462 netlink_deliver_fn *deliver;
463 netlink_link_quality_fn *set_quality;
464 netlink_set_mtu_fn *set_mtu;
469 /* Returns public key as a malloced hex string */
470 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
472 /* Fills buffer (up to buflen) with shared secret */
473 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
474 int32_t secretlen, cstring_t rempublic,
475 uint8_t *sharedsecret, int32_t buflen);
478 int32_t len; /* Approximate size of modulus in bytes */
479 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
480 dh_makepublic_fn *makepublic;
481 dh_makeshared_fn *makeshared;
486 typedef void *hash_init_fn(void);
487 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
488 typedef void hash_final_fn(void *st, uint8_t *digest);
490 int32_t len; /* Hash output length in bytes */
492 hash_update_fn *update;
493 hash_final_fn *final;
496 /* BUFFER interface */
500 cstring_t owner; /* Set to constant string */
501 uint32_t flags; /* How paranoid should we be? */
502 struct cloc loc; /* Where we were defined */
505 int32_t size; /* Size of buffer contents */
506 int32_t alloclen; /* Total length allocated at base */
509 /***** LOG functions *****/
511 #define M_DEBUG_CONFIG 0x001
512 #define M_DEBUG_PHASE 0x002
513 #define M_DEBUG 0x004
515 #define M_NOTICE 0x010
516 #define M_WARNING 0x020
518 #define M_SECURITY 0x080
519 #define M_FATAL 0x100
521 /* The fatal() family of functions require messages that do not end in '\n' */
522 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
523 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
524 extern NORETURN(fatal_status(int status, const char *message, ...))
526 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
529 /* The cfgfatal() family of functions require messages that end in '\n' */
530 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
531 const char *message, ...)) FORMAT(printf,3,4);
532 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
533 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
534 cstring_t facility, const char *message,
537 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
539 const char *message, ...))
542 extern void Message(uint32_t class, const char *message, ...)
544 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
546 /***** END of log functions *****/
548 #define STRING2(x) #x
549 #define STRING(x) STRING2(x)
551 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
553 #endif /* secnet_h */