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
;
306 /* Return True if the packet was processed, and shouldn't be passed to
307 any other potential receivers. */
308 typedef bool_t
comm_notify_fn(void *state
, struct buffer_if
*buf
,
309 struct sockaddr_in
*source
);
310 typedef void comm_request_notify_fn(void *commst
, void *nst
,
312 typedef void comm_release_notify_fn(void *commst
, void *nst
,
314 typedef bool_t
comm_sendmsg_fn(void *commst
, struct buffer_if
*buf
,
315 struct sockaddr_in
*dest
);
318 int32_t min_start_pad
;
320 comm_request_notify_fn
*request_notify
;
321 comm_release_notify_fn
*release_notify
;
322 comm_sendmsg_fn
*sendmsg
;
327 typedef void log_msg_fn(void *st
, int class, const char *message
, ...);
328 typedef void log_vmsg_fn(void *st
, int class, const char *message
,
335 /* (convenience functions, defined in util.c) */
336 extern void slilog(struct log_if
*lf
, int class, const char *message
, ...)
338 extern void vslilog(struct log_if
*lf
, int class, const char *message
, va_list)
343 /* Pretty much a placeholder; allows starting and stopping of processing,
345 typedef void site_control_fn(void *st
, bool_t run
);
346 typedef uint32_t site_status_fn(void *st
);
349 site_control_fn
*control
;
350 site_status_fn
*status
;
353 /* TRANSFORM interface */
355 /* A reversable transformation. Transforms buffer in-place; may add
356 data to start or end. Maximum amount of data to be added specified
357 in max_start_pad and max_end_pad. (Reverse transformations decrease
358 length, of course.) Transformations may be key-dependent, in which
359 case key material is passed in at initialisation time. They may
360 also depend on internal factors (eg. time) and keep internal
361 state. A struct transform_if only represents a particular type of
362 transformation; instances of the transformation (eg. with
363 particular key material) have a different C type. */
365 typedef struct transform_inst_if
*transform_createinstance_fn(void *st
);
366 typedef bool_t
transform_setkey_fn(void *st
, uint8_t *key
, int32_t keylen
);
367 typedef void transform_delkey_fn(void *st
);
368 typedef void transform_destroyinstance_fn(void *st
);
369 /* Returns 0 for 'all is well', any other value for a problem */
370 typedef uint32_t transform_apply_fn(void *st
, struct buffer_if
*buf
,
371 const char **errmsg
);
373 struct transform_inst_if
{
375 transform_setkey_fn
*setkey
;
376 transform_delkey_fn
*delkey
;
377 transform_apply_fn
*forwards
;
378 transform_apply_fn
*reverse
;
379 transform_destroyinstance_fn
*destroy
;
382 struct transform_if
{
384 int32_t max_start_pad
; /* these three are all <<< INT_MAX */
387 transform_createinstance_fn
*create
;
390 /* NETLINK interface */
392 /* Used by netlink to deliver to site, and by site to deliver to
393 netlink. cid is the client identifier returned by
394 netlink_regnets_fn. If buf has size 0 then the function is just
395 being called for its site-effects (eg. making the site code attempt
396 to bring up a network link) */
397 typedef void netlink_deliver_fn(void *st
, struct buffer_if
*buf
);
398 /* site code can tell netlink when outgoing packets will be dropped,
399 so netlink can generate appropriate ICMP and make routing decisions */
400 #define LINK_QUALITY_DOWN 0 /* No chance of a packet being delivered */
401 #define LINK_QUALITY_DOWN_STALE_ADDRESS 1 /* Link down, old address information */
402 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 2 /* Link down, current address information */
403 #define LINK_QUALITY_UP 3 /* Link active */
404 #define MAXIMUM_LINK_QUALITY 3
405 typedef void netlink_link_quality_fn(void *st
, uint32_t quality
);
406 typedef void netlink_register_fn(void *st
, netlink_deliver_fn
*deliver
,
407 void *dst
, int32_t max_start_pad
,
408 int32_t max_end_pad
);
409 typedef void netlink_output_config_fn(void *st
, struct buffer_if
*buf
);
410 typedef bool_t
netlink_check_config_fn(void *st
, struct buffer_if
*buf
);
411 typedef void netlink_set_mtu_fn(void *st
, int32_t new_mtu
);
414 netlink_register_fn
*reg
;
415 netlink_deliver_fn
*deliver
;
416 netlink_link_quality_fn
*set_quality
;
417 netlink_output_config_fn
*output_config
;
418 netlink_check_config_fn
*check_config
;
419 netlink_set_mtu_fn
*set_mtu
;
424 /* Returns public key as a malloced hex string */
425 typedef string_t
dh_makepublic_fn(void *st
, uint8_t *secret
,
427 /* Fills buffer (up to buflen) with shared secret */
428 typedef void dh_makeshared_fn(void *st
, uint8_t *secret
,
429 int32_t secretlen
, cstring_t rempublic
,
430 uint8_t *sharedsecret
, int32_t buflen
);
433 int32_t len
; /* Approximate size of modulus in bytes */
434 dh_makepublic_fn
*makepublic
;
435 dh_makeshared_fn
*makeshared
;
440 typedef void *hash_init_fn(void);
441 typedef void hash_update_fn(void *st
, const void *buf
, int32_t len
);
442 typedef void hash_final_fn(void *st
, uint8_t *digest
);
444 int32_t len
; /* Hash output length in bytes */
446 hash_update_fn
*update
;
447 hash_final_fn
*final
;
450 /* BUFFER interface */
454 cstring_t owner
; /* Set to constant string */
455 uint32_t flags
; /* How paranoid should we be? */
456 struct cloc loc
; /* Where we were defined */
459 int32_t size
; /* Size of buffer contents */
460 int32_t len
; /* Total length allocated at base */
463 /***** LOG functions *****/
465 #define M_DEBUG_CONFIG 0x001
466 #define M_DEBUG_PHASE 0x002
467 #define M_DEBUG 0x004
469 #define M_NOTICE 0x010
470 #define M_WARNING 0x020
472 #define M_SECURITY 0x080
473 #define M_FATAL 0x100
475 /* The fatal() family of functions require messages that do not end in '\n' */
476 extern NORETURN(fatal(const char *message
, ...));
477 extern NORETURN(fatal_perror(const char *message
, ...));
478 extern NORETURN(fatal_status(int status
, const char *message
, ...));
479 extern NORETURN(fatal_perror_status(int status
, const char *message
, ...));
481 /* The cfgfatal() family of functions require messages that end in '\n' */
482 extern NORETURN(cfgfatal(struct cloc loc
, cstring_t facility
,
483 const char *message
, ...));
484 extern void cfgfile_postreadcheck(struct cloc loc
, FILE *f
);
485 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f
, struct cloc loc
,
486 cstring_t facility
, const char *message
,
488 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f
, struct cloc loc
,
490 const char *message
, ...));
492 extern void Message(uint32_t class, const char *message
, ...)
494 extern void log_from_fd(int fd
, cstring_t prefix
, struct log_if
*log
);
496 /***** END of log functions *****/
498 #endif /* secnet_h */