1 /* Core interface of secnet, to be used by all modules */
13 #include <sys/types.h>
15 #include <netinet/in.h>
17 typedef char *string_t;
18 typedef const char *cstring_t;
19 typedef enum {False,True} bool_t;
21 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
22 __FILE__,__LINE__); } } while(0)
26 extern char version[];
29 extern uint32_t message_level;
30 extern bool_t secnet_is_daemon;
31 extern struct log_if *system_log;
34 extern void start_signal_handling(void);
36 /***** CONFIGURATION support *****/
38 extern bool_t just_check_config; /* If True then we're going to exit after
39 reading the configuration file */
40 extern bool_t background; /* If True then we'll eventually run as a daemon */
42 typedef struct dict dict_t; /* Configuration dictionary */
43 typedef struct closure closure_t;
44 typedef struct item item_t;
45 typedef struct list list_t; /* A list of items */
47 /* Configuration file location, for error-reporting */
53 /* Modules export closures, which can be invoked from the configuration file.
54 "Invoking" a closure usually returns another closure (of a different
55 type), but can actually return any configuration object. */
56 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
57 dict_t *context, list_t *data);
59 cstring_t description; /* For debugging */
60 uint32_t type; /* Central registry... */
62 void *interface; /* Interface for use inside secnet; depends on type */
65 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
78 /* Note that it is unwise to use this structure directly; use the list
79 manipulation functions instead. */
85 /* In the following two lookup functions, NULL means 'not found' */
86 /* Lookup a value in the specified dictionary, or its parents */
87 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
88 /* Lookup a value in just the specified dictionary */
89 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
90 /* Add a value to the specified dictionary */
91 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
92 /* Obtain an array of keys in the dictionary. malloced; caller frees */
93 extern cstring_t *dict_keys(dict_t *dict);
95 /* List-manipulation functions */
96 extern list_t *list_new(void);
97 extern int32_t list_length(list_t *a);
98 extern list_t *list_append(list_t *a, item_t *i);
99 extern list_t *list_append_list(list_t *a, list_t *b);
100 /* Returns an item from the list (index starts at 0), or NULL */
101 extern item_t *list_elem(list_t *l, int32_t index);
103 /* Convenience functions */
104 extern list_t *new_closure(closure_t *cl);
105 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
106 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
107 bool_t fail_if_invalid, cstring_t desc,
109 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
110 cstring_t desc, struct cloc loc);
111 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
112 cstring_t desc, struct cloc loc);
113 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
114 cstring_t desc, struct cloc loc,
116 /* return value can safely be assigned to int32_t */
117 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
118 cstring_t desc, struct cloc loc, bool_t def);
123 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
124 struct flagstr *f, cstring_t desc);
125 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
128 /***** END of configuration support *****/
130 /***** UTILITY functions *****/
132 extern char *safe_strdup(const char *string, const char *message);
133 extern void *safe_malloc(size_t size, const char *message);
134 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
136 extern int sys_cmd(const char *file, const char *argc, ...);
138 extern uint64_t now_global;
139 extern struct timeval tv_now_global;
141 static const uint64_t *const now = &now_global;
142 static const struct timeval *const tv_now = &tv_now_global;
144 /* "now" is current program time, in milliseconds. It is derived
145 from tv_now. Both are provided by the event loop. */
147 /***** END of utility functions *****/
149 /***** START of max_start_pad handling *****/
151 extern int32_t site_max_start_pad, transform_max_start_pad,
154 void update_max_start_pad(int32_t *our_module_global, int32_t our_instance);
155 int32_t calculate_max_start_pad(void);
157 /***** END of max_start_pad handling *****/
159 /***** SCHEDULING support */
161 /* If nfds_io is insufficient for your needs, set it to the required
162 number and return ERANGE. timeout is in milliseconds; if it is too
163 high then lower it. It starts at -1 (==infinite) */
164 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
166 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
168 /* Register interest in the main loop of the program. Before a call
169 to poll() your supplied beforepoll function will be called. After
170 the call to poll() the supplied afterpoll function will be called.
171 max_nfds is a _hint_ about the maximum number of struct pollfd
172 structures you may require - you can always ask for more in
174 extern void register_for_poll(void *st, beforepoll_fn *before,
175 afterpoll_fn *after, int32_t max_nfds,
178 /***** END of scheduling support */
180 /***** PROGRAM LIFETIME support */
182 /* The secnet program goes through a number of phases in its lifetime.
183 Module code may arrange to be called just as various phases are
186 Remember to update the table in util.c if changing the set of
191 PHASE_GETOPTS, /* Process command-line arguments */
192 PHASE_READCONFIG, /* Parse and process configuration file */
193 PHASE_SETUP, /* Process information in configuration */
194 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
195 PHASE_GETRESOURCES, /* Obtain all external resources */
196 PHASE_DROPPRIV, /* Last chance for privileged operations */
198 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
199 /* Keep this last: */
203 typedef void hook_fn(void *self, uint32_t newphase);
204 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
205 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
207 extern uint32_t current_phase;
208 extern void enter_phase(uint32_t new_phase);
210 /* Some features (like netlink 'soft' routes) require that secnet
211 retain root privileges. They should indicate that here when
213 extern bool_t require_root_privileges;
214 extern cstring_t require_root_privileges_explanation;
216 /***** END of program lifetime support *****/
218 /***** MODULE support *****/
220 /* Module initialisation function type - modules export one function of
221 this type which is called to initialise them. For dynamically loaded
222 modules it's called "secnet_module". */
223 typedef void init_module(dict_t *dict);
225 extern void init_builtin_modules(dict_t *dict);
227 extern init_module resolver_module;
228 extern init_module random_module;
229 extern init_module udp_module;
230 extern init_module util_module;
231 extern init_module site_module;
232 extern init_module transform_eax_module;
233 extern init_module transform_cbcmac_module;
234 extern init_module netlink_module;
235 extern init_module rsa_module;
236 extern init_module dh_module;
237 extern init_module md5_module;
238 extern init_module slip_module;
239 extern init_module tun_module;
240 extern init_module sha1_module;
241 extern init_module log_module;
243 /***** END of module support *****/
245 /***** CLOSURE TYPES and interface definitions *****/
248 #define CL_RESOLVER 1
249 #define CL_RANDOMSRC 2
250 #define CL_RSAPUBKEY 3
251 #define CL_RSAPRIVKEY 4
256 #define CL_TRANSFORM 9
260 #define CL_NETLINK 14
264 /* PURE closure requires no interface */
266 /* RESOLVER interface */
268 /* Answers to queries are delivered to a function of this
269 type. 'address' will be NULL if there was a problem with the query. It
270 will be freed once resolve_answer_fn returns. It is in network byte
272 /* XXX extend to be able to provide multiple answers */
273 typedef void resolve_answer_fn(void *st, struct in_addr *addr);
274 typedef bool_t resolve_request_fn(void *st, cstring_t name,
275 resolve_answer_fn *cb, void *cst);
278 resolve_request_fn *request;
281 /* RANDOMSRC interface */
283 /* Return some random data. Returns TRUE for success. */
284 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
292 /* RSAPUBKEY interface */
294 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
295 cstring_t signature);
296 struct rsapubkey_if {
298 rsa_checksig_fn *check;
301 /* RSAPRIVKEY interface */
303 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
304 struct rsaprivkey_if {
306 rsa_makesig_fn *sign;
312 /* This struct is pure data; in particular comm's clients may
314 /* Everyone is also guaranteed that all padding is set to zero, ie
315 that comm_addrs referring to semantically identical peers will
316 compare equal with memcmp. Anyone who constructs a comm_addr
317 must start by memsetting it with FILLZERO, or some
319 struct comm_if *comm;
320 struct sockaddr_in sin;
323 /* Return True if the packet was processed, and shouldn't be passed to
324 any other potential receivers. */
325 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
326 const struct comm_addr *source);
327 typedef void comm_request_notify_fn(void *commst, void *nst,
329 typedef void comm_release_notify_fn(void *commst, void *nst,
331 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
332 const struct comm_addr *dest);
333 typedef const char *comm_addr_to_string_fn(void *commst,
334 const struct comm_addr *ca);
335 /* Returned string is in a static buffer. */
338 comm_request_notify_fn *request_notify;
339 comm_release_notify_fn *release_notify;
340 comm_sendmsg_fn *sendmsg;
341 comm_addr_to_string_fn *addr_to_string;
346 typedef void log_msg_fn(void *st, int class, const char *message, ...);
347 typedef void log_vmsg_fn(void *st, int class, const char *message,
351 log_msg_fn *logfn; /* Do not call these directly - you don't get */
352 log_vmsg_fn *vlogfn; /* printf format checking. Use [v]slilog instead */
354 /* (convenience functions, defined in util.c) */
355 extern void slilog(struct log_if *lf, int class, const char *message, ...)
357 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
362 /* Pretty much a placeholder; allows starting and stopping of processing,
364 typedef void site_control_fn(void *st, bool_t run);
365 typedef uint32_t site_status_fn(void *st);
368 site_control_fn *control;
369 site_status_fn *status;
372 /* TRANSFORM interface */
374 /* A reversable transformation. Transforms buffer in-place; may add
375 data to start or end. (Reverse transformations decrease
376 length, of course.) Transformations may be key-dependent, in which
377 case key material is passed in at initialisation time. They may
378 also depend on internal factors (eg. time) and keep internal
379 state. A struct transform_if only represents a particular type of
380 transformation; instances of the transformation (eg. with
381 particular key material) have a different C type. The same
382 secret key will be used in opposite directions between a pair of
383 secnets; one of these pairs will get direction==False, the other True. */
385 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
386 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
388 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
389 typedef void transform_delkey_fn(void *st);
390 typedef void transform_destroyinstance_fn(void *st);
393 * 1: for any other problem
394 * 2: message decrypted but sequence number was out of range
396 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
397 const char **errmsg);
399 struct transform_inst_if {
401 transform_setkey_fn *setkey;
402 transform_valid_fn *valid;
403 transform_delkey_fn *delkey;
404 transform_apply_fn *forwards;
405 transform_apply_fn *reverse;
406 transform_destroyinstance_fn *destroy;
409 struct transform_if {
411 int capab_transformnum;
412 int32_t keylen; /* <<< INT_MAX */
413 transform_createinstance_fn *create;
416 /* NETLINK interface */
418 /* Used by netlink to deliver to site, and by site to deliver to
419 netlink. cid is the client identifier returned by
420 netlink_regnets_fn. If buf has size 0 then the function is just
421 being called for its site-effects (eg. making the site code attempt
422 to bring up a network link) */
423 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
424 /* site code can tell netlink when outgoing packets will be dropped,
425 so netlink can generate appropriate ICMP and make routing decisions */
426 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
427 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
428 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
429 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
430 #define LINK_QUALITY_UP 4 /* Link active */
431 #define MAXIMUM_LINK_QUALITY 3
432 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
433 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
435 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
436 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
437 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
440 netlink_register_fn *reg;
441 netlink_deliver_fn *deliver;
442 netlink_link_quality_fn *set_quality;
443 netlink_set_mtu_fn *set_mtu;
448 /* Returns public key as a malloced hex string */
449 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
451 /* Fills buffer (up to buflen) with shared secret */
452 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
453 int32_t secretlen, cstring_t rempublic,
454 uint8_t *sharedsecret, int32_t buflen);
457 int32_t len; /* Approximate size of modulus in bytes */
458 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
459 dh_makepublic_fn *makepublic;
460 dh_makeshared_fn *makeshared;
465 typedef void *hash_init_fn(void);
466 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
467 typedef void hash_final_fn(void *st, uint8_t *digest);
469 int32_t len; /* Hash output length in bytes */
471 hash_update_fn *update;
472 hash_final_fn *final;
475 /* BUFFER interface */
479 cstring_t owner; /* Set to constant string */
480 uint32_t flags; /* How paranoid should we be? */
481 struct cloc loc; /* Where we were defined */
484 int32_t size; /* Size of buffer contents */
485 int32_t len; /* Total length allocated at base */
488 /***** LOG functions *****/
490 #define M_DEBUG_CONFIG 0x001
491 #define M_DEBUG_PHASE 0x002
492 #define M_DEBUG 0x004
494 #define M_NOTICE 0x010
495 #define M_WARNING 0x020
497 #define M_SECURITY 0x080
498 #define M_FATAL 0x100
500 /* The fatal() family of functions require messages that do not end in '\n' */
501 extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
502 extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
503 extern NORETURN(fatal_status(int status, const char *message, ...))
505 extern NORETURN(fatal_perror_status(int status, const char *message, ...))
508 /* The cfgfatal() family of functions require messages that end in '\n' */
509 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
510 const char *message, ...)) FORMAT(printf,3,4);
511 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
512 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
513 cstring_t facility, const char *message,
516 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
518 const char *message, ...))
521 extern void Message(uint32_t class, const char *message, ...)
523 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
525 /***** END of log functions *****/
527 #define STRING2(x) #x
528 #define STRING(x) STRING2(x)
530 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
532 #endif /* secnet_h */