xref: /netbsd/external/bsd/unbound/dist/util/net_help.h (revision 17b85d8b)
1 /*
2  * util/net_help.h - network help functions
3  *
4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains functions to perform network related tasks.
40  */
41 
42 #ifndef NET_HELP_H
43 #define NET_HELP_H
44 #include "util/log.h"
45 #include "util/random.h"
46 struct sock_list;
47 struct regional;
48 struct config_strlist;
49 
50 /** DNS constants for uint16_t style flag manipulation. host byteorder.
51  *                                1  1  1  1  1  1
52  *  0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
53  * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
54  * |QR|   Opcode  |AA|TC|RD|RA| Z|AD|CD|   RCODE   |
55  * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
56  */
57 /** CD flag */
58 #define BIT_CD 0x0010
59 /** AD flag */
60 #define BIT_AD 0x0020
61 /** Z flag */
62 #define BIT_Z  0x0040
63 /** RA flag */
64 #define BIT_RA 0x0080
65 /** RD flag */
66 #define BIT_RD 0x0100
67 /** TC flag */
68 #define BIT_TC 0x0200
69 /** AA flag */
70 #define BIT_AA 0x0400
71 /** QR flag */
72 #define BIT_QR 0x8000
73 /** get RCODE bits from uint16 flags */
74 #define FLAGS_GET_RCODE(f) ((f) & 0xf)
75 /** set RCODE bits in uint16 flags */
76 #define FLAGS_SET_RCODE(f, r) (f = (((f) & 0xfff0) | (r)))
77 
78 /** timeout in milliseconds for UDP queries to auth servers. */
79 #define UDP_AUTH_QUERY_TIMEOUT 3000
80 /** Advertised version of EDNS capabilities */
81 #define EDNS_ADVERTISED_VERSION         0
82 /** Advertised size of EDNS capabilities */
83 extern uint16_t EDNS_ADVERTISED_SIZE;
84 /** bits for EDNS bitfield */
85 #define EDNS_DO 0x8000 /* Dnssec Ok */
86 /** byte size of ip4 address */
87 #define INET_SIZE 4
88 /** byte size of ip6 address */
89 #define INET6_SIZE 16
90 
91 /** DNSKEY zone sign key flag */
92 #define DNSKEY_BIT_ZSK 0x0100
93 /** DNSKEY secure entry point, KSK flag */
94 #define DNSKEY_BIT_SEP 0x0001
95 
96 /** return a random 16-bit number given a random source */
97 #define GET_RANDOM_ID(rnd) (((unsigned)ub_random(rnd)>>8) & 0xffff)
98 
99 /** minimal responses when positive answer */
100 extern int MINIMAL_RESPONSES;
101 
102 /** rrset order roundrobin */
103 extern int RRSET_ROUNDROBIN;
104 
105 /** log tag queries with name instead of 'info' for filtering */
106 extern int LOG_TAG_QUERYREPLY;
107 
108 /**
109  * See if string is ip4 or ip6.
110  * @param str: IP specification.
111  * @return: true if string addr is an ip6 specced address.
112  */
113 int str_is_ip6(const char* str);
114 
115 /**
116  * Set fd nonblocking.
117  * @param s: file descriptor.
118  * @return: 0 on error (error is printed to log).
119  */
120 int fd_set_nonblock(int s);
121 
122 /**
123  * Set fd (back to) blocking.
124  * @param s: file descriptor.
125  * @return: 0 on error (error is printed to log).
126  */
127 int fd_set_block(int s);
128 
129 /**
130  * See if number is a power of 2.
131  * @param num: the value.
132  * @return: true if the number is a power of 2.
133  */
134 int is_pow2(size_t num);
135 
136 /**
137  * Allocate memory and copy over contents.
138  * @param data: what to copy over.
139  * @param len: length of data.
140  * @return: NULL on malloc failure, or newly malloced data.
141  */
142 void* memdup(void* data, size_t len);
143 
144 /**
145  * Prints the sockaddr in readable format with log_info. Debug helper.
146  * @param v: at what verbosity level to print this.
147  * @param str: descriptive string printed with it.
148  * @param addr: the sockaddr to print. Can be ip4 or ip6.
149  * @param addrlen: length of addr.
150  */
151 void log_addr(enum verbosity_value v, const char* str,
152 	struct sockaddr_storage* addr, socklen_t addrlen);
153 
154 /**
155  * Prints zone name and sockaddr in readable format with log_info. Debug.
156  * @param v: at what verbosity level to print this.
157  * @param str: descriptive string printed with it.
158  * @param zone: DNS domain name, uncompressed wireformat.
159  * @param addr: the sockaddr to print. Can be ip4 or ip6.
160  * @param addrlen: length of addr.
161  */
162 void log_name_addr(enum verbosity_value v, const char* str, uint8_t* zone,
163 	struct sockaddr_storage* addr, socklen_t addrlen);
164 
165 /**
166  * Log errno and addr.
167  * @param str: descriptive string printed with it.
168  * @param err: errno string to print, i.e. strerror(errno).
169  * @param addr: the sockaddr to print. Can be ip4 or ip6.
170  * @param addrlen: length of addr.
171  */
172 void log_err_addr(const char* str, const char* err,
173 	struct sockaddr_storage* addr, socklen_t addrlen);
174 
175 /**
176  * Convert address string, with "@port" appendix, to sockaddr.
177  * Uses DNS port by default.
178  * @param str: the string
179  * @param addr: where to store sockaddr.
180  * @param addrlen: length of stored sockaddr is returned.
181  * @return 0 on error.
182  */
183 int extstrtoaddr(const char* str, struct sockaddr_storage* addr,
184 	socklen_t* addrlen);
185 
186 /**
187  * Convert ip address string and port to sockaddr.
188  * @param ip: ip4 or ip6 address string.
189  * @param port: port number, host format.
190  * @param addr: where to store sockaddr.
191  * @param addrlen: length of stored sockaddr is returned.
192  * @return 0 on error.
193  */
194 int ipstrtoaddr(const char* ip, int port, struct sockaddr_storage* addr,
195 	socklen_t* addrlen);
196 
197 /**
198  * Convert ip netblock (ip/netsize) string and port to sockaddr.
199  * performs a copy internally to avoid writing over 'ip' string.
200  * @param ip: ip4 or ip6 address string.
201  * @param port: port number, host format.
202  * @param addr: where to store sockaddr.
203  * @param addrlen: length of stored sockaddr is returned.
204  * @param net: netblock size is returned.
205  * @return 0 on error.
206  */
207 int netblockstrtoaddr(const char* ip, int port, struct sockaddr_storage* addr,
208 	socklen_t* addrlen, int* net);
209 
210 /**
211  * Convert address string, with "@port" appendix, to sockaddr.
212  * It can also have an "#tls-auth-name" appendix (after the port).
213  * The returned auth_name string is a pointer into the input string.
214  * Uses DNS port by default; TLS port when a "#tls-auth-name" is configured.
215  * @param str: the string
216  * @param addr: where to store sockaddr.
217  * @param addrlen: length of stored sockaddr is returned.
218  * @param auth_name: returned pointer to tls_auth_name, or NULL if none.
219  * @return 0 on error.
220  */
221 int authextstrtoaddr(char* str, struct sockaddr_storage* addr,
222 	socklen_t* addrlen, char** auth_name);
223 
224 /**
225  * Convert domain string, with "@port" appendix, to dname.
226  * It can also have an "#tls-auth-name" appendix (after the port).
227  * The return port is the parsed port.
228  * Uses DNS port by default; TLS port when a "#tls-auth-name" is configured.
229  * The returned auth_name string is a pointer into the input string.
230  * @param str: the string
231  * @param port: pointer to be assigned the parsed port value.
232  * @param auth_name: returned pointer to tls_auth_name, or NULL if none.
233  * @return pointer to the dname.
234  */
235 uint8_t* authextstrtodname(char* str, int* port, char** auth_name);
236 
237 /**
238  * Store port number into sockaddr structure
239  * @param addr: sockaddr structure, ip4 or ip6.
240  * @param addrlen: length of addr.
241  * @param port: port number to put into the addr.
242  */
243 void sockaddr_store_port(struct sockaddr_storage* addr, socklen_t addrlen,
244 	int port);
245 
246 /**
247  * Print string with neat domain name, type and class.
248  * @param v: at what verbosity level to print this.
249  * @param str: string of message.
250  * @param name: domain name uncompressed wireformat.
251  * @param type: host format RR type.
252  * @param dclass: host format RR class.
253  */
254 void log_nametypeclass(enum verbosity_value v, const char* str,
255 	uint8_t* name, uint16_t type, uint16_t dclass);
256 
257 /**
258  * Like log_nametypeclass, but logs with log_query for query logging
259  */
260 void log_query_in(const char* str, uint8_t* name, uint16_t type,
261 	uint16_t dclass);
262 
263 /**
264  * Compare two sockaddrs. Imposes an ordering on the addresses.
265  * Compares address and port.
266  * @param addr1: address 1.
267  * @param len1: lengths of addr1.
268  * @param addr2: address 2.
269  * @param len2: lengths of addr2.
270  * @return: 0 if addr1 == addr2. -1 if addr1 is smaller, +1 if larger.
271  */
272 int sockaddr_cmp(struct sockaddr_storage* addr1, socklen_t len1,
273 	struct sockaddr_storage* addr2, socklen_t len2);
274 
275 /**
276  * Compare two sockaddrs. Compares address, not the port.
277  * @param addr1: address 1.
278  * @param len1: lengths of addr1.
279  * @param addr2: address 2.
280  * @param len2: lengths of addr2.
281  * @return: 0 if addr1 == addr2. -1 if addr1 is smaller, +1 if larger.
282  */
283 int sockaddr_cmp_addr(struct sockaddr_storage* addr1, socklen_t len1,
284 	struct sockaddr_storage* addr2, socklen_t len2);
285 
286 /**
287  * Checkout address family.
288  * @param addr: the sockaddr to examine.
289  * @param len: the length of addr.
290  * @return: true if sockaddr is ip6.
291  */
292 int addr_is_ip6(struct sockaddr_storage* addr, socklen_t len);
293 
294 /**
295  * Make sure the sockaddr ends in zeroes. For tree insertion and subsequent
296  * comparison.
297  * @param addr: the ip4 or ip6 addr.
298  * @param len: length of addr.
299  * @param net: number of bits to leave untouched, the rest of the netblock
300  * 	address is zeroed.
301  */
302 void addr_mask(struct sockaddr_storage* addr, socklen_t len, int net);
303 
304 /**
305  * See how many bits are shared, equal, between two addrs.
306  * @param addr1: first addr.
307  * @param net1: netblock size of first addr.
308  * @param addr2: second addr.
309  * @param net2: netblock size of second addr.
310  * @param addrlen: length of first addr and of second addr.
311  * 	They must be of the same length (i.e. same type IP4, IP6).
312  * @return: number of bits the same.
313  */
314 int addr_in_common(struct sockaddr_storage* addr1, int net1,
315 	struct sockaddr_storage* addr2, int net2, socklen_t addrlen);
316 
317 /**
318  * Put address into string, works for IPv4 and IPv6.
319  * @param addr: address
320  * @param addrlen: length of address
321  * @param buf: result string stored here
322  * @param len: length of buf.
323  * On failure a string with "error" is stored inside.
324  */
325 void addr_to_str(struct sockaddr_storage* addr, socklen_t addrlen,
326 	char* buf, size_t len);
327 
328 /**
329  * See if sockaddr is an ipv6 mapped ipv4 address, "::ffff:0.0.0.0"
330  * @param addr: address
331  * @param addrlen: length of address
332  * @return true if so
333  */
334 int addr_is_ip4mapped(struct sockaddr_storage* addr, socklen_t addrlen);
335 
336 /**
337  * See if sockaddr is 255.255.255.255.
338  * @param addr: address
339  * @param addrlen: length of address
340  * @return true if so
341  */
342 int addr_is_broadcast(struct sockaddr_storage* addr, socklen_t addrlen);
343 
344 /**
345  * See if sockaddr is 0.0.0.0 or ::0.
346  * @param addr: address
347  * @param addrlen: length of address
348  * @return true if so
349  */
350 int addr_is_any(struct sockaddr_storage* addr, socklen_t addrlen);
351 
352 /**
353  * Insert new socket list item. If fails logs error.
354  * @param list: pointer to pointer to first item.
355  * @param addr: address or NULL if 'cache'.
356  * @param len: length of addr, or 0 if 'cache'.
357  * @param region: where to allocate
358  */
359 void sock_list_insert(struct sock_list** list, struct sockaddr_storage* addr,
360 	socklen_t len, struct regional* region);
361 
362 /**
363  * Append one list to another.  Must both be from same qstate(regional).
364  * @param list: pointer to result list that is modified.
365  * @param add: item(s) to add.  They are prepended to list.
366  */
367 void sock_list_prepend(struct sock_list** list, struct sock_list* add);
368 
369 /**
370  * Find addr in list.
371  * @param list: to search in
372  * @param addr: address to look for.
373  * @param len: length. Can be 0, look for 'cache entry'.
374  * @return true if found.
375  */
376 int sock_list_find(struct sock_list* list, struct sockaddr_storage* addr,
377         socklen_t len);
378 
379 /**
380  * Merge socklist into another socket list.  Allocates the new entries
381  * freshly and copies them over, so also performs a region switchover.
382  * Allocation failures are logged.
383  * @param list: the destination list (checked for duplicates)
384  * @param region: where to allocate
385  * @param add: the list of entries to add.
386  */
387 void sock_list_merge(struct sock_list** list, struct regional* region,
388 	struct sock_list* add);
389 
390 /**
391  * Log libcrypto error with descriptive string. Calls log_err().
392  * @param str: what failed.
393  */
394 void log_crypto_err(const char* str);
395 
396 /**
397  * Log libcrypto error from errcode with descriptive string, calls log_err.
398  * @param str: what failed.
399  * @param err: error code from ERR_get_error.
400  */
401 void log_crypto_err_code(const char* str, unsigned long err);
402 
403 /**
404  * Log certificate details verbosity, string, of X509 cert
405  * @param level: verbosity level
406  * @param str: string to prefix on output
407  * @param cert: X509* structure.
408  */
409 void log_cert(unsigned level, const char* str, void* cert);
410 
411 /**
412  * Set SSL_OP_NOxxx options on SSL context to disable bad crypto
413  * @param ctxt: SSL_CTX*
414  * @return false on failure.
415  */
416 int listen_sslctx_setup(void* ctxt);
417 
418 /**
419  * Further setup of listening SSL context, after keys loaded.
420  * @param ctxt: SSL_CTX*
421  */
422 void listen_sslctx_setup_2(void* ctxt);
423 
424 /**
425  * create SSL listen context
426  * @param key: private key file.
427  * @param pem: public key cert.
428  * @param verifypem: if nonNULL, verifylocation file.
429  * return SSL_CTX* or NULL on failure (logged).
430  */
431 void* listen_sslctx_create(char* key, char* pem, char* verifypem);
432 
433 /**
434  * create SSL connect context
435  * @param key: if nonNULL (also pem nonNULL), the client private key.
436  * @param pem: client public key (or NULL if key is NULL).
437  * @param verifypem: if nonNULL used for verifylocation file.
438  * @param wincert: add system certificate store to ctx (add to verifypem ca
439  * 	certs).
440  * @return SSL_CTX* or NULL on failure (logged).
441  */
442 void* connect_sslctx_create(char* key, char* pem, char* verifypem, int wincert);
443 
444 /**
445  * accept a new fd and wrap it in a BIO in SSL
446  * @param sslctx: the SSL_CTX to use (from listen_sslctx_create()).
447  * @param fd: from accept, nonblocking.
448  * @return SSL or NULL on alloc failure.
449  */
450 void* incoming_ssl_fd(void* sslctx, int fd);
451 
452 /**
453  * connect a new fd and wrap it in a BIO in SSL
454  * @param sslctx: the SSL_CTX to use (from connect_sslctx_create())
455  * @param fd: from connect.
456  * @return SSL or NULL on alloc failure
457  */
458 void* outgoing_ssl_fd(void* sslctx, int fd);
459 
460 /**
461  * check if authname SSL functionality is available, false if not
462  * @param auth_name: the name for the remote server, used for error print.
463  * @return false if SSL functionality to check the SSL name is not available.
464  */
465 int check_auth_name_for_ssl(char* auth_name);
466 
467 /**
468  * set auth name on SSL for verification
469  * @param ssl: SSL* to set
470  * @param auth_name: if NULL nothing happens, otherwise the name to check.
471  * @param use_sni: if SNI will be used.
472  * @return 1 on success or NULL auth_name, 0 on failure.
473  */
474 int set_auth_name_on_ssl(void* ssl, char* auth_name, int use_sni);
475 
476 /**
477  * Initialize openssl locking for thread safety
478  * @return false on failure (alloc failure).
479  */
480 int ub_openssl_lock_init(void);
481 
482 /**
483  * De-init the allocated openssl locks
484  */
485 void ub_openssl_lock_delete(void);
486 
487 /**
488  * setup TLS session ticket
489  * @param sslctx: the SSL_CTX to use (from connect_sslctx_create())
490  * @param tls_session_ticket_keys: TLS ticket secret filenames
491  * @return false on failure (alloc failure).
492  */
493 int listen_sslctx_setup_ticket_keys(void* sslctx,
494 	struct config_strlist* tls_session_ticket_keys);
495 
496 /** Free memory used for TLS session ticket keys */
497 void listen_sslctx_delete_ticket_keys(void);
498 
499 /**
500  * RPZ format netblock to network byte order address and netblock
501  * example RPZ netblock format dnames:
502  *  - 24.10.100.51.198.rpz-ip -> 198.51.100.10/24
503  *  - 32.10.zz.db8.2001.rpz-ip -> 2001:db8:0:0:0:0:0:10/32
504  * @param dname: the dname containing RPZ format netblock
505  * @param dnamelen: length of dname
506  * @param addr: where to store sockaddr.
507  * @param addrlen: length of stored sockaddr is returned.
508  * @param net: where to store netmask
509  * @param af: where to store address family.
510  * @return 0 on error.
511  */
512 int netblockdnametoaddr(uint8_t* dname, size_t dnamelen,
513 	struct sockaddr_storage* addr, socklen_t* addrlen, int* net, int* af);
514 
515 /** Return strerror or wsastrerror for socket error printout */
516 char* sock_strerror(int errn);
517 /** close the socket with close, or wsa closesocket */
518 void sock_close(int socket);
519 
520 #endif /* NET_HELP_H */
521