4 * contains the functions needed for TSIG [RFC2845]
6 * (c) 2005-2006 NLnet Labs
7 * See the file LICENSE for the license
10 #include <ldns/config.h>
12 #include <ldns/ldns.h>
17 #include <openssl/hmac.h>
18 #include <openssl/md5.h>
22 ldns_tsig_algorithm(ldns_tsig_credentials *tc)
28 ldns_tsig_keyname(ldns_tsig_credentials *tc)
34 ldns_tsig_keydata(ldns_tsig_credentials *tc)
40 ldns_tsig_keyname_clone(ldns_tsig_credentials *tc)
42 return strdup(tc->keyname);
46 ldns_tsig_keydata_clone(ldns_tsig_credentials *tc)
48 return strdup(tc->keydata);
52 * Makes an exact copy of the wire, but with the tsig rr removed
55 ldns_tsig_prepare_pkt_wire(uint8_t *wire, size_t wire_len, size_t *result_len)
57 uint8_t *wire2 = NULL;
69 if(wire_len < LDNS_HEADER_SIZE) {
72 /* fake parse the wire */
73 qd_count = LDNS_QDCOUNT(wire);
74 an_count = LDNS_ANCOUNT(wire);
75 ns_count = LDNS_NSCOUNT(wire);
76 ar_count = LDNS_ARCOUNT(wire);
84 pos = LDNS_HEADER_SIZE;
86 for (i = 0; i < qd_count; i++) {
87 status = ldns_wire2rr(&rr, wire, wire_len, &pos, LDNS_SECTION_QUESTION);
88 if (status != LDNS_STATUS_OK) {
94 for (i = 0; i < an_count; i++) {
95 status = ldns_wire2rr(&rr, wire, wire_len, &pos, LDNS_SECTION_ANSWER);
96 if (status != LDNS_STATUS_OK) {
102 for (i = 0; i < ns_count; i++) {
103 status = ldns_wire2rr(&rr, wire, wire_len, &pos, LDNS_SECTION_AUTHORITY);
104 if (status != LDNS_STATUS_OK) {
110 for (i = 0; i < ar_count; i++) {
111 status = ldns_wire2rr(&rr, wire, wire_len, &pos,
112 LDNS_SECTION_ADDITIONAL);
113 if (status != LDNS_STATUS_OK) {
120 wire2 = LDNS_XMALLOC(uint8_t, *result_len);
124 memcpy(wire2, wire, *result_len);
126 ldns_write_uint16(wire2 + LDNS_ARCOUNT_OFF, ar_count);
132 static const EVP_MD *
133 ldns_digest_function(char *name)
135 /* these are the mandatory algorithms from RFC4635 */
136 /* The optional algorithms are not yet implemented */
137 if (strlen(name) == 12
138 && strncasecmp(name, "hmac-sha256.", 11) == 0) {
139 #ifdef HAVE_EVP_SHA256
144 } else if (strlen(name) == 10
145 && strncasecmp(name, "hmac-sha1.", 9) == 0) {
147 } else if (strlen(name) == 25
148 && strncasecmp(name, "hmac-md5.sig-alg.reg.int.", 25)
159 ldns_tsig_mac_new(ldns_rdf **tsig_mac, uint8_t *pkt_wire, size_t pkt_wire_size,
160 const char *key_data, ldns_rdf *key_name_rdf, ldns_rdf *fudge_rdf,
161 ldns_rdf *algorithm_rdf, ldns_rdf *time_signed_rdf, ldns_rdf *error_rdf,
162 ldns_rdf *other_data_rdf, ldns_rdf *orig_mac_rdf, int tsig_timers_only)
167 unsigned char *mac_bytes = NULL;
168 unsigned char *key_bytes = NULL;
170 const EVP_MD *digester;
171 char *algorithm_name = NULL;
172 unsigned int md_len = EVP_MAX_MD_SIZE;
173 ldns_rdf *result = NULL;
174 ldns_buffer *data_buffer = NULL;
175 ldns_rdf *canonical_key_name_rdf = NULL;
176 ldns_rdf *canonical_algorithm_rdf = NULL;
178 if (key_name_rdf == NULL || algorithm_rdf == NULL) {
179 return LDNS_STATUS_NULL;
181 canonical_key_name_rdf = ldns_rdf_clone(key_name_rdf);
182 canonical_algorithm_rdf = ldns_rdf_clone(algorithm_rdf);
184 if (canonical_key_name_rdf == NULL
185 || canonical_algorithm_rdf == NULL) {
186 return LDNS_STATUS_MEM_ERR;
189 * prepare the digestable information
191 data_buffer = ldns_buffer_new(LDNS_MAX_PACKETLEN);
193 status = LDNS_STATUS_MEM_ERR;
196 /* if orig_mac is not NULL, add it too */
198 (void) ldns_rdf2buffer_wire(data_buffer, orig_mac_rdf);
200 ldns_buffer_write(data_buffer, pkt_wire, pkt_wire_size);
201 if (!tsig_timers_only) {
202 ldns_dname2canonical(canonical_key_name_rdf);
203 (void)ldns_rdf2buffer_wire(data_buffer,
204 canonical_key_name_rdf);
205 ldns_buffer_write_u16(data_buffer, LDNS_RR_CLASS_ANY);
206 ldns_buffer_write_u32(data_buffer, 0);
207 ldns_dname2canonical(canonical_algorithm_rdf);
208 (void)ldns_rdf2buffer_wire(data_buffer,
209 canonical_algorithm_rdf);
211 (void)ldns_rdf2buffer_wire(data_buffer, time_signed_rdf);
212 (void)ldns_rdf2buffer_wire(data_buffer, fudge_rdf);
213 if (!tsig_timers_only) {
214 (void)ldns_rdf2buffer_wire(data_buffer, error_rdf);
215 (void)ldns_rdf2buffer_wire(data_buffer, other_data_rdf);
218 wireformat = (char *) data_buffer->_data;
219 wiresize = (int) ldns_buffer_position(data_buffer);
221 algorithm_name = ldns_rdf2str(algorithm_rdf);
222 if(!algorithm_name) {
223 status = LDNS_STATUS_MEM_ERR;
227 /* prepare the key */
228 key_bytes = LDNS_XMALLOC(unsigned char,
229 ldns_b64_pton_calculate_size(strlen(key_data)));
231 status = LDNS_STATUS_MEM_ERR;
234 key_size = ldns_b64_pton(key_data, key_bytes,
235 ldns_b64_pton_calculate_size(strlen(key_data)));
237 status = LDNS_STATUS_INVALID_B64;
241 /* 2 spare bytes for the length */
242 mac_bytes = LDNS_XMALLOC(unsigned char, md_len+2);
244 status = LDNS_STATUS_MEM_ERR;
247 memset(mac_bytes, 0, md_len+2);
249 digester = ldns_digest_function(algorithm_name);
252 (void) HMAC(digester, key_bytes, key_size, (void *)wireformat,
253 (size_t) wiresize, mac_bytes + 2, &md_len);
255 ldns_write_uint16(mac_bytes, md_len);
256 result = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_INT16_DATA, md_len + 2,
259 status = LDNS_STATUS_CRYPTO_UNKNOWN_ALGO;
263 status = LDNS_STATUS_OK;
265 LDNS_FREE(mac_bytes);
266 LDNS_FREE(key_bytes);
267 LDNS_FREE(algorithm_name);
268 ldns_buffer_free(data_buffer);
269 ldns_rdf_free(canonical_algorithm_rdf);
270 ldns_rdf_free(canonical_key_name_rdf);
273 #endif /* HAVE_SSL */
278 ldns_pkt_tsig_verify(ldns_pkt *pkt, uint8_t *wire, size_t wirelen, const char *key_name,
279 const char *key_data, ldns_rdf *orig_mac_rdf)
281 return ldns_pkt_tsig_verify_next(pkt, wire, wirelen, key_name, key_data, orig_mac_rdf, 0);
285 ldns_pkt_tsig_verify_next(ldns_pkt *pkt, uint8_t *wire, size_t wirelen, const char* key_name,
286 const char *key_data, ldns_rdf *orig_mac_rdf, int tsig_timers_only)
289 ldns_rdf *algorithm_rdf;
290 ldns_rdf *time_signed_rdf;
291 ldns_rdf *orig_id_rdf;
293 ldns_rdf *other_data_rdf;
294 ldns_rdf *pkt_mac_rdf;
295 ldns_rdf *my_mac_rdf;
296 ldns_rdf *key_name_rdf = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, key_name);
297 uint16_t pkt_id, orig_pkt_id;
300 uint8_t *prepared_wire = NULL;
301 size_t prepared_wire_size = 0;
303 ldns_rr *orig_tsig = ldns_pkt_tsig(pkt);
305 if (!orig_tsig || ldns_rr_rd_count(orig_tsig) <= 6) {
306 ldns_rdf_deep_free(key_name_rdf);
309 algorithm_rdf = ldns_rr_rdf(orig_tsig, 0);
310 time_signed_rdf = ldns_rr_rdf(orig_tsig, 1);
311 fudge_rdf = ldns_rr_rdf(orig_tsig, 2);
312 pkt_mac_rdf = ldns_rr_rdf(orig_tsig, 3);
313 orig_id_rdf = ldns_rr_rdf(orig_tsig, 4);
314 error_rdf = ldns_rr_rdf(orig_tsig, 5);
315 other_data_rdf = ldns_rr_rdf(orig_tsig, 6);
317 /* remove temporarily */
318 ldns_pkt_set_tsig(pkt, NULL);
319 /* temporarily change the id to the original id */
320 pkt_id = ldns_pkt_id(pkt);
321 orig_pkt_id = ldns_rdf2native_int16(orig_id_rdf);
322 ldns_pkt_set_id(pkt, orig_pkt_id);
324 prepared_wire = ldns_tsig_prepare_pkt_wire(wire, wirelen, &prepared_wire_size);
326 status = ldns_tsig_mac_new(&my_mac_rdf, prepared_wire, prepared_wire_size,
327 key_data, key_name_rdf, fudge_rdf, algorithm_rdf,
328 time_signed_rdf, error_rdf, other_data_rdf, orig_mac_rdf, tsig_timers_only);
330 LDNS_FREE(prepared_wire);
332 if (status != LDNS_STATUS_OK) {
333 ldns_rdf_deep_free(key_name_rdf);
336 /* Put back the values */
337 ldns_pkt_set_tsig(pkt, orig_tsig);
338 ldns_pkt_set_id(pkt, pkt_id);
340 ldns_rdf_deep_free(key_name_rdf);
342 if (ldns_rdf_compare(pkt_mac_rdf, my_mac_rdf) == 0) {
343 ldns_rdf_deep_free(my_mac_rdf);
346 ldns_rdf_deep_free(my_mac_rdf);
350 #endif /* HAVE_SSL */
354 ldns_pkt_tsig_sign(ldns_pkt *pkt, const char *key_name, const char *key_data,
355 uint16_t fudge, const char *algorithm_name, ldns_rdf *query_mac)
357 return ldns_pkt_tsig_sign_next(pkt, key_name, key_data, fudge, algorithm_name, query_mac, 0);
361 ldns_pkt_tsig_sign_next(ldns_pkt *pkt, const char *key_name, const char *key_data,
362 uint16_t fudge, const char *algorithm_name, ldns_rdf *query_mac, int tsig_timers_only)
365 ldns_rdf *key_name_rdf = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, key_name);
366 ldns_rdf *fudge_rdf = NULL;
367 ldns_rdf *orig_id_rdf = NULL;
368 ldns_rdf *algorithm_rdf;
369 ldns_rdf *error_rdf = NULL;
370 ldns_rdf *mac_rdf = NULL;
371 ldns_rdf *other_data_rdf = NULL;
373 ldns_status status = LDNS_STATUS_OK;
375 uint8_t *pkt_wire = NULL;
378 struct timeval tv_time_signed;
379 uint8_t *time_signed = NULL;
380 ldns_rdf *time_signed_rdf = NULL;
382 algorithm_rdf = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, algorithm_name);
383 if(!key_name_rdf || !algorithm_rdf) {
384 status = LDNS_STATUS_MEM_ERR;
388 /* eww don't have create tsigtime rdf yet :( */
390 if (gettimeofday(&tv_time_signed, NULL) == 0) {
391 time_signed = LDNS_XMALLOC(uint8_t, 6);
393 status = LDNS_STATUS_MEM_ERR;
396 ldns_write_uint64_as_uint48(time_signed,
397 (uint64_t)tv_time_signed.tv_sec);
399 status = LDNS_STATUS_INTERNAL_ERR;
403 time_signed_rdf = ldns_rdf_new(LDNS_RDF_TYPE_TSIGTIME, 6, time_signed);
404 if(!time_signed_rdf) {
405 LDNS_FREE(time_signed);
406 status = LDNS_STATUS_MEM_ERR;
410 fudge_rdf = ldns_native2rdf_int16(LDNS_RDF_TYPE_INT16, fudge);
412 orig_id_rdf = ldns_native2rdf_int16(LDNS_RDF_TYPE_INT16, ldns_pkt_id(pkt));
414 error_rdf = ldns_native2rdf_int16(LDNS_RDF_TYPE_INT16, 0);
416 other_data_rdf = ldns_native2rdf_int16_data(0, NULL);
418 if(!fudge_rdf || !orig_id_rdf || !error_rdf || !other_data_rdf) {
419 status = LDNS_STATUS_MEM_ERR;
423 if (ldns_pkt2wire(&pkt_wire, pkt, &pkt_wire_len) != LDNS_STATUS_OK) {
424 status = LDNS_STATUS_ERR;
428 status = ldns_tsig_mac_new(&mac_rdf, pkt_wire, pkt_wire_len,
429 key_data, key_name_rdf, fudge_rdf, algorithm_rdf,
430 time_signed_rdf, error_rdf, other_data_rdf, query_mac, tsig_timers_only);
438 /* Create the TSIG RR */
439 tsig_rr = ldns_rr_new();
441 status = LDNS_STATUS_MEM_ERR;
444 ldns_rr_set_owner(tsig_rr, key_name_rdf);
445 ldns_rr_set_class(tsig_rr, LDNS_RR_CLASS_ANY);
446 ldns_rr_set_type(tsig_rr, LDNS_RR_TYPE_TSIG);
447 ldns_rr_set_ttl(tsig_rr, 0);
449 ldns_rr_push_rdf(tsig_rr, algorithm_rdf);
450 ldns_rr_push_rdf(tsig_rr, time_signed_rdf);
451 ldns_rr_push_rdf(tsig_rr, fudge_rdf);
452 ldns_rr_push_rdf(tsig_rr, mac_rdf);
453 ldns_rr_push_rdf(tsig_rr, orig_id_rdf);
454 ldns_rr_push_rdf(tsig_rr, error_rdf);
455 ldns_rr_push_rdf(tsig_rr, other_data_rdf);
457 ldns_pkt_set_tsig(pkt, tsig_rr);
463 ldns_rdf_free(key_name_rdf);
464 ldns_rdf_free(algorithm_rdf);
465 ldns_rdf_free(time_signed_rdf);
466 ldns_rdf_free(fudge_rdf);
467 ldns_rdf_free(orig_id_rdf);
468 ldns_rdf_free(error_rdf);
469 ldns_rdf_free(other_data_rdf);
472 #endif /* HAVE_SSL */