1 /* Core interface of secnet, to be used by all modules */
11 #include <sys/types.h>
13 #include <netinet/in.h>
16 * Macros added by SGT for endianness-independence
18 #define GET_32BIT_MSB_FIRST(cp) \
19 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
20 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
21 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
22 ((unsigned long)(unsigned char)(cp)[3]))
24 #define PUT_32BIT_MSB_FIRST(cp, value) ( \
25 (cp)[0] = (char)((value) >> 24), \
26 (cp)[1] = (char)((value) >> 16), \
27 (cp)[2] = (char)((value) >> 8), \
28 (cp)[3] = (char)(value) )
30 typedef char *string_t;
31 typedef const char *cstring_t;
32 typedef enum {False,True} bool_t;
34 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
35 __FILE__,__LINE__); } } while(0)
39 extern char version[];
42 extern uint32_t message_level;
43 extern bool_t secnet_is_daemon;
44 extern struct log_if *system_log;
47 extern void start_signal_handling(void);
49 /***** CONFIGURATION support *****/
51 extern bool_t just_check_config; /* If True then we're going to exit after
52 reading the configuration file */
53 extern bool_t background; /* If True then we'll eventually run as a daemon */
55 typedef struct dict dict_t; /* Configuration dictionary */
56 typedef struct closure closure_t;
57 typedef struct item item_t;
58 typedef struct list list_t; /* A list of items */
60 /* Configuration file location, for error-reporting */
66 /* Modules export closures, which can be invoked from the configuration file.
67 "Invoking" a closure usually returns another closure (of a different
68 type), but can actually return any configuration object. */
69 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
70 dict_t *context, list_t *data);
72 cstring_t description; /* For debugging */
73 uint32_t type; /* Central registry... */
75 void *interface; /* Interface for use inside secnet; depends on type */
78 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
91 /* Note that it is unwise to use this structure directly; use the list
92 manipulation functions instead. */
98 /* In the following two lookup functions, NULL means 'not found' */
99 /* Lookup a value in the specified dictionary, or its parents */
100 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
101 /* Lookup a value in just the specified dictionary */
102 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
103 /* Add a value to the specified dictionary */
104 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
105 /* Obtain an array of keys in the dictionary. malloced; caller frees */
106 extern cstring_t *dict_keys(dict_t *dict);
108 /* List-manipulation functions */
109 extern list_t *list_new(void);
110 extern int32_t list_length(list_t *a);
111 extern list_t *list_append(list_t *a, item_t *i);
112 extern list_t *list_append_list(list_t *a, list_t *b);
113 /* Returns an item from the list (index starts at 0), or NULL */
114 extern item_t *list_elem(list_t *l, int32_t index);
116 /* Convenience functions */
117 extern list_t *new_closure(closure_t *cl);
118 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
119 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
120 bool_t fail_if_invalid, cstring_t desc,
122 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
123 cstring_t desc, struct cloc loc);
124 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
125 cstring_t desc, struct cloc loc);
126 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
127 cstring_t desc, struct cloc loc,
129 /* return value can safely be assigned to int32_t */
130 extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
131 cstring_t desc, struct cloc loc, bool_t def);
136 extern uint32_t string_to_word(cstring_t s, struct cloc loc,
137 struct flagstr *f, cstring_t desc);
138 extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
141 /***** END of configuration support *****/
143 /***** UTILITY functions *****/
145 extern char *safe_strdup(const char *string, const char *message);
146 extern void *safe_malloc(size_t size, const char *message);
147 extern void *safe_malloc_ary(size_t size, size_t count, const char *message);
149 extern int sys_cmd(const char *file, const char *argc, ...);
151 extern uint64_t now_global;
152 extern struct timeval tv_now_global;
154 static const uint64_t *const now = &now_global;
155 static const struct timeval *const tv_now = &tv_now_global;
157 /* "now" is current program time, in milliseconds. It is derived
158 from tv_now. Both are provided by the event loop. */
160 /***** END of utility functions *****/
162 /***** SCHEDULING support */
164 /* If nfds_io is insufficient for your needs, set it to the required
165 number and return ERANGE. timeout is in milliseconds; if it is too
166 high then lower it. It starts at -1 (==infinite) */
167 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
169 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);
171 /* Register interest in the main loop of the program. Before a call
172 to poll() your supplied beforepoll function will be called. After
173 the call to poll() the supplied afterpoll function will be called.
174 max_nfds is a _hint_ about the maximum number of struct pollfd
175 structures you may require - you can always ask for more in
177 extern void register_for_poll(void *st, beforepoll_fn *before,
178 afterpoll_fn *after, int32_t max_nfds,
181 /***** END of scheduling support */
183 /***** PROGRAM LIFETIME support */
185 /* The secnet program goes through a number of phases in its lifetime.
186 Module code may arrange to be called just as various phases are
190 #define PHASE_GETOPTS 1 /* Process command-line arguments */
191 #define PHASE_READCONFIG 2 /* Parse and process configuration file */
192 #define PHASE_SETUP 3 /* Process information in configuration */
193 #define PHASE_GETRESOURCES 4 /* Obtain all external resources */
194 #define PHASE_DROPPRIV 5 /* Last chance for privileged operations */
196 #define PHASE_SHUTDOWN 7 /* About to die; delete key material, etc. */
199 typedef void hook_fn(void *self, uint32_t newphase);
200 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
201 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
203 extern uint32_t current_phase;
204 extern void enter_phase(uint32_t new_phase);
206 /* Some features (like netlink 'soft' routes) require that secnet
207 retain root privileges. They should indicate that here when
209 extern bool_t require_root_privileges;
210 extern cstring_t require_root_privileges_explanation;
212 /***** END of program lifetime support *****/
214 /***** MODULE support *****/
216 /* Module initialisation function type - modules export one function of
217 this type which is called to initialise them. For dynamically loaded
218 modules it's called "secnet_module". */
219 typedef void init_module(dict_t *dict);
221 extern void init_builtin_modules(dict_t *dict);
223 extern init_module resolver_module;
224 extern init_module random_module;
225 extern init_module udp_module;
226 extern init_module util_module;
227 extern init_module site_module;
228 extern init_module transform_module;
229 extern init_module netlink_module;
230 extern init_module rsa_module;
231 extern init_module dh_module;
232 extern init_module md5_module;
233 extern init_module slip_module;
234 extern init_module tun_module;
235 extern init_module sha1_module;
236 extern init_module log_module;
238 /***** END of module support *****/
240 /***** CLOSURE TYPES and interface definitions *****/
243 #define CL_RESOLVER 1
244 #define CL_RANDOMSRC 2
245 #define CL_RSAPUBKEY 3
246 #define CL_RSAPRIVKEY 4
251 #define CL_TRANSFORM 9
255 #define CL_NETLINK 14
259 /* PURE closure requires no interface */
261 /* RESOLVER interface */
263 /* Answers to queries are delivered to a function of this
264 type. 'address' will be NULL if there was a problem with the query. It
265 will be freed once resolve_answer_fn returns. It is in network byte
267 /* XXX extend to be able to provide multiple answers */
268 typedef void resolve_answer_fn(void *st, struct in_addr *addr);
269 typedef bool_t resolve_request_fn(void *st, cstring_t name,
270 resolve_answer_fn *cb, void *cst);
273 resolve_request_fn *request;
276 /* RANDOMSRC interface */
278 /* Return some random data. Returns TRUE for success. */
279 typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
287 /* RSAPUBKEY interface */
289 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
290 cstring_t signature);
291 struct rsapubkey_if {
293 rsa_checksig_fn *check;
296 /* RSAPRIVKEY interface */
298 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
299 struct rsaprivkey_if {
301 rsa_makesig_fn *sign;
307 /* This struct is pure data; in particular comm's clients may
309 /* Everyone is also guaranteed that all padding is set to zero, ie
310 that comm_addrs referring to semantically identical peers will
311 compare equal with memcmp. */
312 struct comm_if *comm;
314 struct sockaddr_in sin;
318 /* Return True if the packet was processed, and shouldn't be passed to
319 any other potential receivers. */
320 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
321 const struct comm_addr *source);
322 typedef void comm_request_notify_fn(void *commst, void *nst,
324 typedef void comm_release_notify_fn(void *commst, void *nst,
326 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
327 const struct comm_addr *dest);
328 typedef bool_t comm_addr_construct_fn(void *commst, struct comm_addr *ca,
329 const struct sockaddr_in *sin);
330 /* Fills in ca->comm an ca->priv. *sin must have no nonzero padding,
331 so must have been FILLZERO'd before its useful fields were filled in.
332 The resulting ca->comm has been constructed likewise, as required
333 above. On failure, logs error, returns false on failure.*/
334 typedef const char *comm_addr_to_string_fn(void *commst,
335 const struct comm_addr *ca);
336 /* Returned string is in a static buffer. */
339 int32_t min_start_pad;
341 comm_request_notify_fn *request_notify;
342 comm_release_notify_fn *release_notify;
343 comm_sendmsg_fn *sendmsg;
344 comm_addr_construct_fn *addr_construct;
345 comm_addr_to_string_fn *addr_to_string;
350 typedef void log_msg_fn(void *st, int class, const char *message, ...);
351 typedef void log_vmsg_fn(void *st, int class, const char *message,
358 /* (convenience functions, defined in util.c) */
359 extern void slilog(struct log_if *lf, int class, const char *message, ...)
361 extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
366 /* Pretty much a placeholder; allows starting and stopping of processing,
368 typedef void site_control_fn(void *st, bool_t run);
369 typedef uint32_t site_status_fn(void *st);
372 site_control_fn *control;
373 site_status_fn *status;
376 /* TRANSFORM interface */
378 /* A reversable transformation. Transforms buffer in-place; may add
379 data to start or end. Maximum amount of data to be added specified
380 in max_start_pad and max_end_pad. (Reverse transformations decrease
381 length, of course.) Transformations may be key-dependent, in which
382 case key material is passed in at initialisation time. They may
383 also depend on internal factors (eg. time) and keep internal
384 state. A struct transform_if only represents a particular type of
385 transformation; instances of the transformation (eg. with
386 particular key material) have a different C type. */
388 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
389 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen);
390 typedef void transform_delkey_fn(void *st);
391 typedef void transform_destroyinstance_fn(void *st);
392 /* Returns 0 for 'all is well', any other value for a problem */
393 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
394 const char **errmsg);
396 struct transform_inst_if {
398 transform_setkey_fn *setkey;
399 transform_delkey_fn *delkey;
400 transform_apply_fn *forwards;
401 transform_apply_fn *reverse;
402 transform_destroyinstance_fn *destroy;
405 struct transform_if {
407 int32_t max_start_pad; /* these three are all <<< INT_MAX */
410 transform_createinstance_fn *create;
413 /* NETLINK interface */
415 /* Used by netlink to deliver to site, and by site to deliver to
416 netlink. cid is the client identifier returned by
417 netlink_regnets_fn. If buf has size 0 then the function is just
418 being called for its site-effects (eg. making the site code attempt
419 to bring up a network link) */
420 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
421 /* site code can tell netlink when outgoing packets will be dropped,
422 so netlink can generate appropriate ICMP and make routing decisions */
423 #define LINK_QUALITY_DOWN 0 /* No chance of a packet being delivered */
424 #define LINK_QUALITY_DOWN_STALE_ADDRESS 1 /* Link down, old address information */
425 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 2 /* Link down, current address information */
426 #define LINK_QUALITY_UP 3 /* Link active */
427 #define MAXIMUM_LINK_QUALITY 3
428 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
429 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
430 void *dst, int32_t max_start_pad,
431 int32_t max_end_pad);
432 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
433 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
434 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
437 netlink_register_fn *reg;
438 netlink_deliver_fn *deliver;
439 netlink_link_quality_fn *set_quality;
440 netlink_output_config_fn *output_config;
441 netlink_check_config_fn *check_config;
442 netlink_set_mtu_fn *set_mtu;
447 /* Returns public key as a malloced hex string */
448 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
450 /* Fills buffer (up to buflen) with shared secret */
451 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
452 int32_t secretlen, cstring_t rempublic,
453 uint8_t *sharedsecret, int32_t buflen);
456 int32_t len; /* Approximate size of modulus in bytes */
457 dh_makepublic_fn *makepublic;
458 dh_makeshared_fn *makeshared;
463 typedef void *hash_init_fn(void);
464 typedef void hash_update_fn(void *st, const void *buf, int32_t len);
465 typedef void hash_final_fn(void *st, uint8_t *digest);
467 int32_t len; /* Hash output length in bytes */
469 hash_update_fn *update;
470 hash_final_fn *final;
473 /* BUFFER interface */
477 cstring_t owner; /* Set to constant string */
478 uint32_t flags; /* How paranoid should we be? */
479 struct cloc loc; /* Where we were defined */
482 int32_t size; /* Size of buffer contents */
483 int32_t len; /* Total length allocated at base */
486 /***** LOG functions *****/
488 #define M_DEBUG_CONFIG 0x001
489 #define M_DEBUG_PHASE 0x002
490 #define M_DEBUG 0x004
492 #define M_NOTICE 0x010
493 #define M_WARNING 0x020
495 #define M_SECURITY 0x080
496 #define M_FATAL 0x100
498 /* The fatal() family of functions require messages that do not end in '\n' */
499 extern NORETURN(fatal(const char *message, ...));
500 extern NORETURN(fatal_perror(const char *message, ...));
501 extern NORETURN(fatal_status(int status, const char *message, ...));
502 extern NORETURN(fatal_perror_status(int status, const char *message, ...));
504 /* The cfgfatal() family of functions require messages that end in '\n' */
505 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
506 const char *message, ...));
507 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
508 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
509 cstring_t facility, const char *message,
511 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
513 const char *message, ...));
515 extern void Message(uint32_t class, const char *message, ...)
517 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
519 /***** END of log functions *****/
521 #define STRING2(x) #x
522 #define STRING(x) STRING2(x)
524 #define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
526 #endif /* secnet_h */