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)
38 extern uint32_t message_level
;
39 extern bool_t secnet_is_daemon
;
40 extern struct log_if
*system_log
;
43 extern void start_signal_handling(void);
45 /***** CONFIGURATION support *****/
47 extern bool_t just_check_config
; /* If True then we're going to exit after
48 reading the configuration file */
49 extern bool_t background
; /* If True then we'll eventually run as a daemon */
51 typedef struct dict dict_t
; /* Configuration dictionary */
52 typedef struct closure closure_t
;
53 typedef struct item item_t
;
54 typedef struct list list_t
; /* A list of items */
56 /* Configuration file location, for error-reporting */
62 /* Modules export closures, which can be invoked from the configuration file.
63 "Invoking" a closure usually returns another closure (of a different
64 type), but can actually return any configuration object. */
65 typedef list_t
*(apply_fn
)(closure_t
*self
, struct cloc loc
,
66 dict_t
*context
, list_t
*data
);
68 cstring_t description
; /* For debugging */
69 uint32_t type
; /* Central registry... */
71 void *interface
; /* Interface for use inside secnet; depends on type */
74 enum types
{ t_null
, t_bool
, t_string
, t_number
, t_dict
, t_closure
};
87 /* Note that it is unwise to use this structure directly; use the list
88 manipulation functions instead. */
94 /* In the following two lookup functions, NULL means 'not found' */
95 /* Lookup a value in the specified dictionary, or its parents */
96 extern list_t
*dict_lookup(dict_t
*dict
, cstring_t key
);
97 /* Lookup a value in just the specified dictionary */
98 extern list_t
*dict_lookup_primitive(dict_t
*dict
, cstring_t key
);
99 /* Add a value to the specified dictionary */
100 extern void dict_add(dict_t
*dict
, cstring_t key
, list_t
*val
);
101 /* Obtain an array of keys in the dictionary. malloced; caller frees */
102 extern cstring_t
*dict_keys(dict_t
*dict
);
104 /* List-manipulation functions */
105 extern list_t
*list_new(void);
106 extern uint32_t list_length(list_t
*a
);
107 extern list_t
*list_append(list_t
*a
, item_t
*i
);
108 extern list_t
*list_append_list(list_t
*a
, list_t
*b
);
109 /* Returns an item from the list (index starts at 0), or NULL */
110 extern item_t
*list_elem(list_t
*l
, uint32_t index
);
112 /* Convenience functions */
113 extern list_t
*new_closure(closure_t
*cl
);
114 extern void add_closure(dict_t
*dict
, cstring_t name
, apply_fn apply
);
115 extern void *find_cl_if(dict_t
*dict
, cstring_t name
, uint32_t type
,
116 bool_t fail_if_invalid
, cstring_t desc
,
118 extern item_t
*dict_find_item(dict_t
*dict
, cstring_t key
, bool_t required
,
119 cstring_t desc
, struct cloc loc
);
120 extern string_t
dict_read_string(dict_t
*dict
, cstring_t key
, bool_t required
,
121 cstring_t desc
, struct cloc loc
);
122 extern uint32_t dict_read_number(dict_t
*dict
, cstring_t key
, bool_t required
,
123 cstring_t desc
, struct cloc loc
,
125 extern bool_t
dict_read_bool(dict_t
*dict
, cstring_t key
, bool_t required
,
126 cstring_t desc
, struct cloc loc
, bool_t def
);
131 extern uint32_t string_to_word(cstring_t s
, struct cloc loc
,
132 struct flagstr
*f
, cstring_t desc
);
133 extern uint32_t string_list_to_word(list_t
*l
, struct flagstr
*f
,
136 /***** END of configuration support *****/
138 /***** UTILITY functions *****/
140 extern char *safe_strdup(const char *string
, const char *message
);
141 extern void *safe_malloc(size_t size
, const char *message
);
143 extern int sys_cmd(const char *file
, const char *argc
, ...);
145 /***** END of utility functions *****/
147 /***** SCHEDULING support */
149 /* "now" is current program time, in milliseconds. It is derived
150 (once) from tv_now. If nfds_io is insufficient for your needs, set
151 it to the required number and return ERANGE. timeout is in milliseconds;
152 if it is too high then lower it. It starts at -1 (==infinite) */
153 typedef int beforepoll_fn(void *st
, struct pollfd
*fds
, int *nfds_io
,
154 int *timeout_io
, const struct timeval
*tv_now
,
156 typedef void afterpoll_fn(void *st
, struct pollfd
*fds
, int nfds
,
157 const struct timeval
*tv_now
, uint64_t *now
);
159 /* Register interest in the main loop of the program. Before a call
160 to poll() your supplied beforepoll function will be called. After
161 the call to poll() the supplied afterpoll function will be called.
162 max_nfds is a _hint_ about the maximum number of struct pollfd
163 structures you may require - you can always ask for more in
165 extern void register_for_poll(void *st
, beforepoll_fn
*before
,
166 afterpoll_fn
*after
, uint32_t max_nfds
,
169 /***** END of scheduling support */
171 /***** PROGRAM LIFETIME support */
173 /* The secnet program goes through a number of phases in its lifetime.
174 Module code may arrange to be called just as various phases are
178 #define PHASE_GETOPTS 1 /* Process command-line arguments */
179 #define PHASE_READCONFIG 2 /* Parse and process configuration file */
180 #define PHASE_SETUP 3 /* Process information in configuration */
181 #define PHASE_GETRESOURCES 4 /* Obtain all external resources */
182 #define PHASE_DROPPRIV 5 /* Last chance for privileged operations */
184 #define PHASE_SHUTDOWN 7 /* About to die; delete key material, etc. */
187 typedef void hook_fn(void *self
, uint32_t newphase
);
188 bool_t
add_hook(uint32_t phase
, hook_fn
*f
, void *state
);
189 bool_t
remove_hook(uint32_t phase
, hook_fn
*f
, void *state
);
191 extern uint32_t current_phase
;
192 extern void enter_phase(uint32_t new_phase
);
194 /* Some features (like netlink 'soft' routes) require that secnet
195 retain root privileges. They should indicate that here when
197 extern bool_t require_root_privileges
;
198 extern cstring_t require_root_privileges_explanation
;
200 /***** END of program lifetime support *****/
202 /***** MODULE support *****/
204 /* Module initialisation function type - modules export one function of
205 this type which is called to initialise them. For dynamically loaded
206 modules it's called "secnet_module". */
207 typedef void init_module(dict_t
*dict
);
209 extern void init_builtin_modules(dict_t
*dict
);
211 extern init_module resolver_module
;
212 extern init_module random_module
;
213 extern init_module udp_module
;
214 extern init_module util_module
;
215 extern init_module site_module
;
216 extern init_module transform_module
;
217 extern init_module netlink_module
;
218 extern init_module rsa_module
;
219 extern init_module dh_module
;
220 extern init_module md5_module
;
221 extern init_module slip_module
;
222 extern init_module tun_module
;
223 extern init_module sha1_module
;
224 extern init_module log_module
;
226 /***** END of module support *****/
228 /***** CLOSURE TYPES and interface definitions *****/
231 #define CL_RESOLVER 1
232 #define CL_RANDOMSRC 2
233 #define CL_RSAPUBKEY 3
234 #define CL_RSAPRIVKEY 4
239 #define CL_TRANSFORM 9
243 #define CL_NETLINK 14
247 /* PURE closure requires no interface */
249 /* RESOLVER interface */
251 /* Answers to queries are delivered to a function of this
252 type. 'address' will be NULL if there was a problem with the query. It
253 will be freed once resolve_answer_fn returns. It is in network byte
255 /* XXX extend to be able to provide multiple answers */
256 typedef void resolve_answer_fn(void *st
, struct in_addr
*addr
);
257 typedef bool_t
resolve_request_fn(void *st
, cstring_t name
,
258 resolve_answer_fn
*cb
, void *cst
);
261 resolve_request_fn
*request
;
264 /* RANDOMSRC interface */
266 /* Return some random data. Returns TRUE for success. */
267 typedef bool_t
random_fn(void *st
, uint32_t bytes
, uint8_t *buff
);
275 /* RSAPUBKEY interface */
277 typedef bool_t
rsa_checksig_fn(void *st
, uint8_t *data
, uint32_t datalen
,
278 cstring_t signature
);
279 struct rsapubkey_if
{
281 rsa_checksig_fn
*check
;
284 /* RSAPRIVKEY interface */
286 typedef string_t
rsa_makesig_fn(void *st
, uint8_t *data
, uint32_t datalen
);
287 struct rsaprivkey_if
{
289 rsa_makesig_fn
*sign
;
294 /* Return True if the packet was processed, and shouldn't be passed to
295 any other potential receivers. */
296 typedef bool_t
comm_notify_fn(void *state
, struct buffer_if
*buf
,
297 struct sockaddr_in
*source
);
298 typedef void comm_request_notify_fn(void *commst
, void *nst
,
300 typedef void comm_release_notify_fn(void *commst
, void *nst
,
302 typedef bool_t
comm_sendmsg_fn(void *commst
, struct buffer_if
*buf
,
303 struct sockaddr_in
*dest
);
306 uint32_t min_start_pad
;
307 uint32_t min_end_pad
;
308 comm_request_notify_fn
*request_notify
;
309 comm_release_notify_fn
*release_notify
;
310 comm_sendmsg_fn
*sendmsg
;
315 typedef void log_msg_fn(void *st
, int class, const char *message
, ...);
316 typedef void log_vmsg_fn(void *st
, int class, const char *message
,
323 /* (convenience function, defined in util.c) */
324 extern void slilog(struct log_if
*lf
, int class, const char *message
, ...)
329 /* Pretty much a placeholder; allows starting and stopping of processing,
331 typedef void site_control_fn(void *st
, bool_t run
);
332 typedef uint32_t site_status_fn(void *st
);
335 site_control_fn
*control
;
336 site_status_fn
*status
;
339 /* TRANSFORM interface */
341 /* A reversable transformation. Transforms buffer in-place; may add
342 data to start or end. Maximum amount of data to be added specified
343 in max_start_pad and max_end_pad. (Reverse transformations decrease
344 length, of course.) Transformations may be key-dependent, in which
345 case key material is passed in at initialisation time. They may
346 also depend on internal factors (eg. time) and keep internal
347 state. A struct transform_if only represents a particular type of
348 transformation; instances of the transformation (eg. with
349 particular key material) have a different C type. */
351 typedef struct transform_inst_if
*transform_createinstance_fn(void *st
);
352 typedef bool_t
transform_setkey_fn(void *st
, uint8_t *key
, uint32_t keylen
);
353 typedef void transform_delkey_fn(void *st
);
354 typedef void transform_destroyinstance_fn(void *st
);
355 /* Returns 0 for 'all is well', any other value for a problem */
356 typedef uint32_t transform_apply_fn(void *st
, struct buffer_if
*buf
,
357 const char **errmsg
);
359 struct transform_inst_if
{
361 transform_setkey_fn
*setkey
;
362 transform_delkey_fn
*delkey
;
363 transform_apply_fn
*forwards
;
364 transform_apply_fn
*reverse
;
365 transform_destroyinstance_fn
*destroy
;
368 struct transform_if
{
370 uint32_t max_start_pad
;
371 uint32_t max_end_pad
;
373 transform_createinstance_fn
*create
;
376 /* NETLINK interface */
378 /* Used by netlink to deliver to site, and by site to deliver to
379 netlink. cid is the client identifier returned by
380 netlink_regnets_fn. If buf has size 0 then the function is just
381 being called for its site-effects (eg. making the site code attempt
382 to bring up a network link) */
383 typedef void netlink_deliver_fn(void *st
, struct buffer_if
*buf
);
384 /* site code can tell netlink when outgoing packets will be dropped,
385 so netlink can generate appropriate ICMP and make routing decisions */
386 #define LINK_QUALITY_DOWN 0 /* No chance of a packet being delivered */
387 #define LINK_QUALITY_DOWN_STALE_ADDRESS 1 /* Link down, old address information */
388 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 2 /* Link down, current address information */
389 #define LINK_QUALITY_UP 3 /* Link active */
390 #define MAXIMUM_LINK_QUALITY 3
391 typedef void netlink_link_quality_fn(void *st
, uint32_t quality
);
392 typedef void netlink_register_fn(void *st
, netlink_deliver_fn
*deliver
,
393 void *dst
, uint32_t max_start_pad
,
394 uint32_t max_end_pad
);
395 typedef void netlink_output_config_fn(void *st
, struct buffer_if
*buf
);
396 typedef bool_t
netlink_check_config_fn(void *st
, struct buffer_if
*buf
);
397 typedef void netlink_set_mtu_fn(void *st
, uint32_t new_mtu
);
400 netlink_register_fn
*reg
;
401 netlink_deliver_fn
*deliver
;
402 netlink_link_quality_fn
*set_quality
;
403 netlink_output_config_fn
*output_config
;
404 netlink_check_config_fn
*check_config
;
405 netlink_set_mtu_fn
*set_mtu
;
410 /* Returns public key as a malloced hex string */
411 typedef string_t
dh_makepublic_fn(void *st
, uint8_t *secret
,
413 /* Fills buffer (up to buflen) with shared secret */
414 typedef void dh_makeshared_fn(void *st
, uint8_t *secret
,
415 uint32_t secretlen
, cstring_t rempublic
,
416 uint8_t *sharedsecret
, uint32_t buflen
);
419 uint32_t len
; /* Approximate size of modulus in bytes */
420 dh_makepublic_fn
*makepublic
;
421 dh_makeshared_fn
*makeshared
;
426 typedef void *hash_init_fn(void);
427 typedef void hash_update_fn(void *st
, uint8_t const *buf
, uint32_t len
);
428 typedef void hash_final_fn(void *st
, uint8_t *digest
);
430 uint32_t len
; /* Hash output length in bytes */
432 hash_update_fn
*update
;
433 hash_final_fn
*final
;
436 /* BUFFER interface */
440 cstring_t owner
; /* Set to constant string */
441 uint32_t flags
; /* How paranoid should we be? */
442 struct cloc loc
; /* Where we were defined */
445 uint32_t size
; /* Size of buffer contents */
446 uint32_t len
; /* Total length allocated at base */
449 /***** LOG functions *****/
451 #define M_DEBUG_CONFIG 0x001
452 #define M_DEBUG_PHASE 0x002
453 #define M_DEBUG 0x004
455 #define M_NOTICE 0x010
456 #define M_WARNING 0x020
458 #define M_SECURITY 0x080
459 #define M_FATAL 0x100
461 /* The fatal() family of functions require messages that do not end in '\n' */
462 extern NORETURN(fatal(const char *message
, ...));
463 extern NORETURN(fatal_perror(const char *message
, ...));
464 extern NORETURN(fatal_status(int status
, const char *message
, ...));
465 extern NORETURN(fatal_perror_status(int status
, const char *message
, ...));
467 /* The cfgfatal() family of functions require messages that end in '\n' */
468 extern NORETURN(cfgfatal(struct cloc loc
, cstring_t facility
,
469 const char *message
, ...));
470 extern void cfgfile_postreadcheck(struct cloc loc
, FILE *f
);
471 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f
, struct cloc loc
,
472 cstring_t facility
, const char *message
,
474 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f
, struct cloc loc
,
476 const char *message
, ...));
478 extern void Message(uint32_t class, const char *message
, ...)
480 extern void log_from_fd(int fd
, cstring_t prefix
, struct log_if
*log
);
482 /***** END of log functions *****/
484 #endif /* secnet_h */