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 /***** SCHEDULING support */
151 /* If nfds_io is insufficient for your needs, set it to the required
152 number and return ERANGE. timeout is in milliseconds; if it is too
153 high then lower it. It starts at -1 (==infinite) */
154 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
156 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
158 /* Register interest in the main loop of the program. Before a call
159 to poll() your supplied beforepoll function will be called. After
160 the call to poll() the supplied afterpoll function will be called.
161 max_nfds is a _hint_ about the maximum number of struct pollfd
162 structures you may require - you can always ask for more in
164 extern void register_for_poll(void *st, beforepoll_fn *before,
165 afterpoll_fn *after, int32_t max_nfds,
168 /***** END of scheduling support */
170 /***** PROGRAM LIFETIME support */
172 /* The secnet program goes through a number of phases in its lifetime.
173 Module code may arrange to be called just as various phases are
176 Remember to update the table in util.c if changing the set of
181 PHASE_GETOPTS, /* Process command-line arguments */
182 PHASE_READCONFIG, /* Parse and process configuration file */
183 PHASE_SETUP, /* Process information in configuration */
184 PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
185 PHASE_GETRESOURCES, /* Obtain all external resources */
186 PHASE_DROPPRIV, /* Last chance for privileged operations */
188 PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
189 /* Keep this last: */
193 typedef void hook_fn(void *self, uint32_t newphase);
194 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
195 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
197 extern uint32_t current_phase;
198 extern void enter_phase(uint32_t new_phase);
200 /* Some features (like netlink 'soft' routes) require that secnet
201 retain root privileges. They should indicate that here when
203 extern bool_t require_root_privileges;
204 extern cstring_t require_root_privileges_explanation;
206 /***** END of program lifetime support *****/
208 /***** MODULE support *****/
210 /* Module initialisation function type - modules export one function of
211 this type which is called to initialise them. For dynamically loaded
212 modules it's called "secnet_module". */
213 typedef void init_module(dict_t *dict);
215 extern void init_builtin_modules(dict_t *dict);
217 extern init_module resolver_module;
218 extern init_module random_module;
219 extern init_module udp_module;
220 extern init_module util_module;
221 extern init_module site_module;
222 extern init_module transform_eax_module;
223 extern init_module transform_cbcmac_module;
224 extern init_module netlink_module;
225 extern init_module rsa_module;
226 extern init_module dh_module;
227 extern init_module md5_module;
228 extern init_module slip_module;
229 extern init_module tun_module;
230 extern init_module sha1_module;
231 extern init_module log_module;
233 /***** END of module support *****/
235 /***** CLOSURE TYPES and interface definitions *****/
238 #define CL_RESOLVER 1
239 #define CL_RANDOMSRC 2
240 #define CL_RSAPUBKEY 3
241 #define CL_RSAPRIVKEY 4
246 #define CL_TRANSFORM 9
250 #define CL_NETLINK 14
254 /* PURE closure requires no interface */
256 /* RESOLVER interface */
258 /* Answers to queries are delivered to a function of this
259 type. 'address' will be NULL if there was a problem with the query. It
260 will be freed once resolve_answer_fn returns. It is in network byte
262 /* XXX extend to be able to provide multiple answers */
263 typedef void resolve_answer_fn(void *st, struct in_addr *addr);
264 typedef bool_t resolve_request_fn(void *st, cstring_t name,
265 resolve_answer_fn *cb, void *cst);
268 resolve_request_fn *request;
271 /* RANDOMSRC interface */
273 /* Return some random data. Returns TRUE for success. */
274 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
282 /* RSAPUBKEY interface */
284 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
285 cstring_t signature);
286 struct rsapubkey_if {
288 rsa_checksig_fn *check;
291 /* RSAPRIVKEY interface */
293 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
294 struct rsaprivkey_if {
296 rsa_makesig_fn *sign;
302 /* This struct is pure data; in particular comm's clients may
304 /* Everyone is also guaranteed that all padding is set to zero, ie
305 that comm_addrs referring to semantically identical peers will
306 compare equal with memcmp. Anyone who constructs a comm_addr
307 must start by memsetting it with FILLZERO, or some
309 struct comm_if *comm;
310 struct sockaddr_in sin;
313 /* Return True if the packet was processed, and shouldn't be passed to
314 any other potential receivers. */
315 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
316 const struct comm_addr *source);
317 typedef void comm_request_notify_fn(void *commst, void *nst,
319 typedef void comm_release_notify_fn(void *commst, void *nst,
321 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
322 const struct comm_addr *dest);
323 typedef const char *comm_addr_to_string_fn(void *commst,
324 const struct comm_addr *ca);
325 /* Returned string is in a static buffer. */
328 int32_t min_start_pad;
330 comm_request_notify_fn *request_notify;
331 comm_release_notify_fn *release_notify;
332 comm_sendmsg_fn *sendmsg;
333 comm_addr_to_string_fn *addr_to_string;
338 typedef void log_msg_fn(void *st, int class, const char *message, ...);
339 typedef void log_vmsg_fn(void *st, int class, const char *message,
346 /* (convenience functions, defined in util.c) */
347 extern void slilog(struct log_if *lf, int class, const char *message, ...)
349 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
354 /* Pretty much a placeholder; allows starting and stopping of processing,
356 typedef void site_control_fn(void *st, bool_t run);
357 typedef uint32_t site_status_fn(void *st);
360 site_control_fn *control;
361 site_status_fn *status;
364 /* TRANSFORM interface */
366 /* A reversable transformation. Transforms buffer in-place; may add
367 data to start or end. Maximum amount of data to be added specified
368 in max_start_pad and max_end_pad. (Reverse transformations decrease
369 length, of course.) Transformations may be key-dependent, in which
370 case key material is passed in at initialisation time. They may
371 also depend on internal factors (eg. time) and keep internal
372 state. A struct transform_if only represents a particular type of
373 transformation; instances of the transformation (eg. with
374 particular key material) have a different C type. The same
375 secret key will be used in opposite directions between a pair of
376 secnets; one of these pairs will get direction==False, the other True. */
378 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
379 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
381 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
382 typedef void transform_delkey_fn(void *st);
383 typedef void transform_destroyinstance_fn(void *st);
386 * 1: for any other problem
387 * 2: message decrypted but sequence number was out of range
389 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
390 const char **errmsg);
392 struct transform_inst_if {
394 transform_setkey_fn *setkey;
395 transform_valid_fn *valid;
396 transform_delkey_fn *delkey;
397 transform_apply_fn *forwards;
398 transform_apply_fn *reverse;
399 transform_destroyinstance_fn *destroy;
402 struct transform_if {
404 int32_t max_start_pad; /* these three are all <<< INT_MAX */
406 int32_t keylen; /* 0 means give the transform exactly as much as there is */
407 transform_createinstance_fn *create;
410 /* NETLINK interface */
412 /* Used by netlink to deliver to site, and by site to deliver to
413 netlink. cid is the client identifier returned by
414 netlink_regnets_fn. If buf has size 0 then the function is just
415 being called for its site-effects (eg. making the site code attempt
416 to bring up a network link) */
417 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
418 /* site code can tell netlink when outgoing packets will be dropped,
419 so netlink can generate appropriate ICMP and make routing decisions */
420 #define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
421 #define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
422 #define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
423 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
424 #define LINK_QUALITY_UP 4 /* Link active */
425 #define MAXIMUM_LINK_QUALITY 3
426 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
427 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
428 void *dst, int32_t max_start_pad,
429 int32_t max_end_pad);
430 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
431 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
432 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
435 netlink_register_fn *reg;
436 netlink_deliver_fn *deliver;
437 netlink_link_quality_fn *set_quality;
438 netlink_set_mtu_fn *set_mtu;
443 /* Returns public key as a malloced hex string */
444 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
446 /* Fills buffer (up to buflen) with shared secret */
447 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
448 int32_t secretlen, cstring_t rempublic,
449 uint8_t *sharedsecret, int32_t buflen);
452 int32_t len; /* Approximate size of modulus in bytes */
453 int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
454 dh_makepublic_fn *makepublic;
455 dh_makeshared_fn *makeshared;
460 typedef void *hash_init_fn(void);
461 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
462 typedef void hash_final_fn(void *st, uint8_t *digest);
464 int32_t len; /* Hash output length in bytes */
466 hash_update_fn *update;
467 hash_final_fn *final;
470 /* BUFFER interface */
474 cstring_t owner; /* Set to constant string */
475 uint32_t flags; /* How paranoid should we be? */
476 struct cloc loc; /* Where we were defined */
479 int32_t size; /* Size of buffer contents */
480 int32_t len; /* Total length allocated at base */
483 /***** LOG functions *****/
485 #define M_DEBUG_CONFIG 0x001
486 #define M_DEBUG_PHASE 0x002
487 #define M_DEBUG 0x004
489 #define M_NOTICE 0x010
490 #define M_WARNING 0x020
492 #define M_SECURITY 0x080
493 #define M_FATAL 0x100
495 /* The fatal() family of functions require messages that do not end in '\n' */
496 extern NORETURN(fatal(const char *message, ...));
497 extern NORETURN(fatal_perror(const char *message, ...));
498 extern NORETURN(fatal_status(int status, const char *message, ...));
499 extern NORETURN(fatal_perror_status(int status, const char *message, ...));
501 /* The cfgfatal() family of functions require messages that end in '\n' */
502 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
503 const char *message, ...));
504 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
505 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
506 cstring_t facility, const char *message,
508 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
510 const char *message, ...));
512 extern void Message(uint32_t class, const char *message, ...)
514 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
516 /***** END of log functions *****/
518 #define STRING2(x) #x
519 #define STRING(x) STRING2(x)
521 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
523 #endif /* secnet_h */