Rename log() to slilog()
[secnet] / secnet.h
1 /* Core interface of secnet, to be used by all modules */
2
3 #ifndef secnet_h
4 #define secnet_h
5
6 #include "config.h"
7 #include <stdlib.h>
8 #include <stdarg.h>
9 #include <stdio.h>
10 #include <sys/poll.h>
11 #include <sys/types.h>
12 #include <sys/time.h>
13 #include <netinet/in.h>
14
15 /*
16 * Macros added by SGT for endianness-independence
17 */
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]))
23
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) )
29
30 typedef char *string_t;
31 typedef const char *cstring_t;
32 typedef enum {False,True} bool_t;
33
34 #define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
35 __FILE__,__LINE__); } } while(0)
36
37 /***** CONFIGURATION support *****/
38
39 extern bool_t just_check_config; /* If True then we're going to exit after
40 reading the configuration file */
41 extern bool_t background; /* If True then we'll eventually run as a daemon */
42
43 typedef struct dict dict_t; /* Configuration dictionary */
44 typedef struct closure closure_t;
45 typedef struct item item_t;
46 typedef struct list list_t; /* A list of items */
47
48 /* Configuration file location, for error-reporting */
49 struct cloc {
50 cstring_t file;
51 uint32_t line;
52 };
53
54 /* Modules export closures, which can be invoked from the configuration file.
55 "Invoking" a closure usually returns another closure (of a different
56 type), but can actually return any configuration object. */
57 typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
58 dict_t *context, list_t *data);
59 struct closure {
60 cstring_t description; /* For debugging */
61 uint32_t type; /* Central registry... */
62 apply_fn *apply;
63 void *interface; /* Interface for use inside secnet; depends on type */
64 };
65
66 enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
67 struct item {
68 enum types type;
69 union {
70 bool_t bool;
71 string_t string;
72 uint32_t number;
73 dict_t *dict;
74 closure_t *closure;
75 } data;
76 struct cloc loc;
77 };
78
79 /* Note that it is unwise to use this structure directly; use the list
80 manipulation functions instead. */
81 struct list {
82 item_t *item;
83 struct list *next;
84 };
85
86 /* In the following two lookup functions, NULL means 'not found' */
87 /* Lookup a value in the specified dictionary, or its parents */
88 extern list_t *dict_lookup(dict_t *dict, cstring_t key);
89 /* Lookup a value in just the specified dictionary */
90 extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
91 /* Add a value to the specified dictionary */
92 extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
93 /* Obtain an array of keys in the dictionary. malloced; caller frees */
94 extern cstring_t *dict_keys(dict_t *dict);
95
96 /* List-manipulation functions */
97 extern list_t *list_new(void);
98 extern uint32_t list_length(list_t *a);
99 extern list_t *list_append(list_t *a, item_t *i);
100 extern list_t *list_append_list(list_t *a, list_t *b);
101 /* Returns an item from the list (index starts at 0), or NULL */
102 extern item_t *list_elem(list_t *l, uint32_t index);
103
104 /* Convenience functions */
105 extern list_t *new_closure(closure_t *cl);
106 extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
107 extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
108 bool_t fail_if_invalid, cstring_t desc,
109 struct cloc loc);
110 extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
111 cstring_t desc, struct cloc loc);
112 extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
113 cstring_t desc, struct cloc loc);
114 extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
115 cstring_t desc, struct cloc loc,
116 uint32_t def);
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);
119 struct flagstr {
120 cstring_t name;
121 uint32_t value;
122 };
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,
126 cstring_t desc);
127
128 /***** END of configuration support *****/
129
130 /***** UTILITY functions *****/
131
132 extern char *safe_strdup(const char *string, const char *message);
133 extern void *safe_malloc(size_t size, const char *message);
134
135 extern int sys_cmd(const char *file, const char *argc, ...);
136
137 /***** END of utility functions *****/
138
139 /***** SCHEDULING support */
140
141 /* "now" is current program time, in milliseconds. It is derived
142 (once) from tv_now. If nfds_io is insufficient for your needs, set
143 it to the required number and return ERANGE. timeout is in milliseconds;
144 if it is too high then lower it. It starts at -1 (==infinite) */
145 typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
146 int *timeout_io, const struct timeval *tv_now,
147 uint64_t *now);
148 typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds,
149 const struct timeval *tv_now, uint64_t *now);
150
151 /* Register interest in the main loop of the program. Before a call
152 to poll() your supplied beforepoll function will be called. After
153 the call to poll() the supplied afterpoll function will be called.
154 max_nfds is a _hint_ about the maximum number of struct pollfd
155 structures you may require - you can always ask for more in
156 *nfds_io. */
157 extern void register_for_poll(void *st, beforepoll_fn *before,
158 afterpoll_fn *after, uint32_t max_nfds,
159 cstring_t desc);
160
161 /***** END of scheduling support */
162
163 /***** PROGRAM LIFETIME support */
164
165 /* The secnet program goes through a number of phases in its lifetime.
166 Module code may arrange to be called just as various phases are
167 entered. */
168
169 #define PHASE_INIT 0
170 #define PHASE_GETOPTS 1 /* Process command-line arguments */
171 #define PHASE_READCONFIG 2 /* Parse and process configuration file */
172 #define PHASE_SETUP 3 /* Process information in configuration */
173 #define PHASE_GETRESOURCES 4 /* Obtain all external resources */
174 #define PHASE_DROPPRIV 5 /* Last chance for privileged operations */
175 #define PHASE_RUN 6
176 #define PHASE_SHUTDOWN 7 /* About to die; delete key material, etc. */
177 #define NR_PHASES 8
178
179 typedef void hook_fn(void *self, uint32_t newphase);
180 bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
181 bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);
182
183 extern uint32_t current_phase;
184 extern void enter_phase(uint32_t new_phase);
185
186 /* Some features (like netlink 'soft' routes) require that secnet
187 retain root privileges. They should indicate that here when
188 appropriate. */
189 extern bool_t require_root_privileges;
190 extern cstring_t require_root_privileges_explanation;
191
192 /***** END of program lifetime support *****/
193
194 /***** MODULE support *****/
195
196 /* Module initialisation function type - modules export one function of
197 this type which is called to initialise them. For dynamically loaded
198 modules it's called "secnet_module". */
199 typedef void init_module(dict_t *dict);
200
201 /***** END of module support *****/
202
203 /***** CLOSURE TYPES and interface definitions *****/
204
205 #define CL_PURE 0
206 #define CL_RESOLVER 1
207 #define CL_RANDOMSRC 2
208 #define CL_RSAPUBKEY 3
209 #define CL_RSAPRIVKEY 4
210 #define CL_COMM 5
211 #define CL_IPIF 6
212 #define CL_LOG 7
213 #define CL_SITE 8
214 #define CL_TRANSFORM 9
215 #define CL_DH 11
216 #define CL_HASH 12
217 #define CL_BUFFER 13
218 #define CL_NETLINK 14
219
220 struct buffer_if;
221
222 /* PURE closure requires no interface */
223
224 /* RESOLVER interface */
225
226 /* Answers to queries are delivered to a function of this
227 type. 'address' will be NULL if there was a problem with the query. It
228 will be freed once resolve_answer_fn returns. It is in network byte
229 order. */
230 /* XXX extend to be able to provide multiple answers */
231 typedef void resolve_answer_fn(void *st, struct in_addr *addr);
232 typedef bool_t resolve_request_fn(void *st, cstring_t name,
233 resolve_answer_fn *cb, void *cst);
234 struct resolver_if {
235 void *st;
236 resolve_request_fn *request;
237 };
238
239 /* RANDOMSRC interface */
240
241 /* Return some random data. Returns TRUE for success. */
242 typedef bool_t random_fn(void *st, uint32_t bytes, uint8_t *buff);
243
244 struct random_if {
245 void *st;
246 bool_t blocking;
247 random_fn *generate;
248 };
249
250 /* RSAPUBKEY interface */
251
252 typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, uint32_t datalen,
253 cstring_t signature);
254 struct rsapubkey_if {
255 void *st;
256 rsa_checksig_fn *check;
257 };
258
259 /* RSAPRIVKEY interface */
260
261 typedef string_t rsa_makesig_fn(void *st, uint8_t *data, uint32_t datalen);
262 struct rsaprivkey_if {
263 void *st;
264 rsa_makesig_fn *sign;
265 };
266
267 /* COMM interface */
268
269 /* Return True if the packet was processed, and shouldn't be passed to
270 any other potential receivers. */
271 typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
272 struct sockaddr_in *source);
273 typedef void comm_request_notify_fn(void *commst, void *nst,
274 comm_notify_fn *fn);
275 typedef void comm_release_notify_fn(void *commst, void *nst,
276 comm_notify_fn *fn);
277 typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
278 struct sockaddr_in *dest);
279 struct comm_if {
280 void *st;
281 uint32_t min_start_pad;
282 uint32_t min_end_pad;
283 comm_request_notify_fn *request_notify;
284 comm_release_notify_fn *release_notify;
285 comm_sendmsg_fn *sendmsg;
286 };
287
288 /* LOG interface */
289
290 typedef void log_msg_fn(void *st, int class, const char *message, ...);
291 typedef void log_vmsg_fn(void *st, int class, const char *message,
292 va_list args);
293 struct log_if {
294 void *st;
295 log_msg_fn *log;
296 log_vmsg_fn *vlog;
297 };
298 /* (convenience function, defined in util.c) */
299 extern void slilog(struct log_if *lf, int class, const char *message, ...)
300 FORMAT(printf,3,4);
301
302 /* SITE interface */
303
304 /* Pretty much a placeholder; allows starting and stopping of processing,
305 key expiry, etc. */
306 typedef void site_control_fn(void *st, bool_t run);
307 typedef uint32_t site_status_fn(void *st);
308 struct site_if {
309 void *st;
310 site_control_fn *control;
311 site_status_fn *status;
312 };
313
314 /* TRANSFORM interface */
315
316 /* A reversable transformation. Transforms buffer in-place; may add
317 data to start or end. Maximum amount of data to be added specified
318 in max_start_pad and max_end_pad. (Reverse transformations decrease
319 length, of course.) Transformations may be key-dependent, in which
320 case key material is passed in at initialisation time. They may
321 also depend on internal factors (eg. time) and keep internal
322 state. A struct transform_if only represents a particular type of
323 transformation; instances of the transformation (eg. with
324 particular key material) have a different C type. */
325
326 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
327 typedef bool_t transform_setkey_fn(void *st, uint8_t *key, uint32_t keylen);
328 typedef void transform_delkey_fn(void *st);
329 typedef void transform_destroyinstance_fn(void *st);
330 /* Returns 0 for 'all is well', any other value for a problem */
331 typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
332 const char **errmsg);
333
334 struct transform_inst_if {
335 void *st;
336 transform_setkey_fn *setkey;
337 transform_delkey_fn *delkey;
338 transform_apply_fn *forwards;
339 transform_apply_fn *reverse;
340 transform_destroyinstance_fn *destroy;
341 };
342
343 struct transform_if {
344 void *st;
345 uint32_t max_start_pad;
346 uint32_t max_end_pad;
347 uint32_t keylen;
348 transform_createinstance_fn *create;
349 };
350
351 /* NETLINK interface */
352
353 /* Used by netlink to deliver to site, and by site to deliver to
354 netlink. cid is the client identifier returned by
355 netlink_regnets_fn. If buf has size 0 then the function is just
356 being called for its site-effects (eg. making the site code attempt
357 to bring up a network link) */
358 typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
359 /* site code can tell netlink when outgoing packets will be dropped,
360 so netlink can generate appropriate ICMP and make routing decisions */
361 #define LINK_QUALITY_DOWN 0 /* No chance of a packet being delivered */
362 #define LINK_QUALITY_DOWN_STALE_ADDRESS 1 /* Link down, old address information */
363 #define LINK_QUALITY_DOWN_CURRENT_ADDRESS 2 /* Link down, current address information */
364 #define LINK_QUALITY_UP 3 /* Link active */
365 #define MAXIMUM_LINK_QUALITY 3
366 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
367 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
368 void *dst, uint32_t max_start_pad,
369 uint32_t max_end_pad);
370 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
371 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
372 typedef void netlink_set_mtu_fn(void *st, uint32_t new_mtu);
373 struct netlink_if {
374 void *st;
375 netlink_register_fn *reg;
376 netlink_deliver_fn *deliver;
377 netlink_link_quality_fn *set_quality;
378 netlink_output_config_fn *output_config;
379 netlink_check_config_fn *check_config;
380 netlink_set_mtu_fn *set_mtu;
381 };
382
383 /* DH interface */
384
385 /* Returns public key as a malloced hex string */
386 typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
387 uint32_t secretlen);
388 /* Fills buffer (up to buflen) with shared secret */
389 typedef void dh_makeshared_fn(void *st, uint8_t *secret,
390 uint32_t secretlen, cstring_t rempublic,
391 uint8_t *sharedsecret, uint32_t buflen);
392 struct dh_if {
393 void *st;
394 uint32_t len; /* Approximate size of modulus in bytes */
395 dh_makepublic_fn *makepublic;
396 dh_makeshared_fn *makeshared;
397 };
398
399 /* HASH interface */
400
401 typedef void *hash_init_fn(void);
402 typedef void hash_update_fn(void *st, uint8_t const *buf, uint32_t len);
403 typedef void hash_final_fn(void *st, uint8_t *digest);
404 struct hash_if {
405 uint32_t len; /* Hash output length in bytes */
406 hash_init_fn *init;
407 hash_update_fn *update;
408 hash_final_fn *final;
409 };
410
411 /* BUFFER interface */
412
413 struct buffer_if {
414 bool_t free;
415 cstring_t owner; /* Set to constant string */
416 uint32_t flags; /* How paranoid should we be? */
417 struct cloc loc; /* Where we were defined */
418 uint8_t *base;
419 uint8_t *start;
420 uint32_t size; /* Size of buffer contents */
421 uint32_t len; /* Total length allocated at base */
422 };
423
424 /***** LOG functions *****/
425
426 #define M_DEBUG_CONFIG 0x001
427 #define M_DEBUG_PHASE 0x002
428 #define M_DEBUG 0x004
429 #define M_INFO 0x008
430 #define M_NOTICE 0x010
431 #define M_WARNING 0x020
432 #define M_ERR 0x040
433 #define M_SECURITY 0x080
434 #define M_FATAL 0x100
435
436 /* The fatal() family of functions require messages that do not end in '\n' */
437 extern NORETURN(fatal(const char *message, ...));
438 extern NORETURN(fatal_perror(const char *message, ...));
439 extern NORETURN(fatal_status(int status, const char *message, ...));
440 extern NORETURN(fatal_perror_status(int status, const char *message, ...));
441
442 /* The cfgfatal() family of functions require messages that end in '\n' */
443 extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
444 const char *message, ...));
445 extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
446 extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
447 cstring_t facility, const char *message,
448 va_list));
449 extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
450 cstring_t facility,
451 const char *message, ...));
452
453 extern void Message(uint32_t class, const char *message, ...)
454 FORMAT(printf,2,3);
455 extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
456
457 /***** END of log functions *****/
458
459 #endif /* secnet_h */