1 /* Copyright (C) 2021 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
2
3 This program is free software: you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation, either version 3 of the License, or
6 (at your option) any later version.
7
8 This program is distributed in the hope that it will be useful,
9 but WITHOUT ANY WARRANTY; without even the implied warranty of
10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 GNU General Public License for more details.
12
13 You should have received a copy of the GNU General Public License
14 along with this program. If not, see <https://www.gnu.org/licenses/>.
15 */
16
17 #include <assert.h>
18
19 #include "knot/common/log.h"
20 #include "knot/updates/apply.h"
21 #include "libknot/libknot.h"
22 #include "contrib/macros.h"
23 #include "contrib/mempattern.h"
24
25 /*! \brief Replaces rdataset of given type with a copy. */
replace_rdataset_with_copy(zone_node_t * node,uint16_t type)26 static int replace_rdataset_with_copy(zone_node_t *node, uint16_t type)
27 {
28 int ret = binode_prepare_change(node, NULL);
29 if (ret != KNOT_EOK) {
30 return ret;
31 }
32
33 // Find data to copy.
34 struct rr_data *data = NULL;
35 for (uint16_t i = 0; i < node->rrset_count; ++i) {
36 if (node->rrs[i].type == type) {
37 data = &node->rrs[i];
38 break;
39 }
40 }
41 if (data == NULL) {
42 return KNOT_EOK;
43 }
44
45 // Create new data.
46 knot_rdataset_t *rrs = &data->rrs;
47 void *copy = malloc(rrs->size);
48 if (copy == NULL) {
49 return KNOT_ENOMEM;
50 }
51
52 memcpy(copy, rrs->rdata, rrs->size);
53
54 // Store new data into node RRS.
55 rrs->rdata = copy;
56
57 return KNOT_EOK;
58 }
59
60 /*! \brief Frees RR dataset. For use when a copy was made. */
clear_new_rrs(zone_node_t * node,uint16_t type)61 static void clear_new_rrs(zone_node_t *node, uint16_t type)
62 {
63 knot_rdataset_t *new_rrs = node_rdataset(node, type);
64 if (new_rrs) {
65 knot_rdataset_clear(new_rrs, NULL);
66 }
67 }
68
69 /*! \brief Logs redundant rrset operation. */
can_log_rrset(const knot_rrset_t * rrset,int pos,apply_ctx_t * ctx,bool remove)70 static void can_log_rrset(const knot_rrset_t *rrset, int pos, apply_ctx_t *ctx, bool remove)
71 {
72 if (!(ctx->flags & APPLY_STRICT)) {
73 return;
74 }
75
76 char type[16];
77 char data[1024];
78 const char *msg = remove ? "cannot remove nonexisting RR" :
79 "cannot add existing RR";
80
81 char *owner = knot_dname_to_str_alloc(rrset->owner);
82 if (owner != NULL && knot_rrtype_to_string(rrset->type, type, sizeof(type)) > 0 &&
83 knot_rrset_txt_dump_data(rrset, pos, data, sizeof(data), &KNOT_DUMP_STYLE_DEFAULT) > 0) {
84 log_zone_debug(ctx->contents->apex->owner,
85 "node %s, type %s, data '%s', %s", owner, type, data, msg);
86 }
87 free(owner);
88 }
89
90 /*! \brief Returns true if given RR is present in node and can be removed. */
can_remove(const zone_node_t * node,const knot_rrset_t * rrset,apply_ctx_t * ctx)91 static bool can_remove(const zone_node_t *node, const knot_rrset_t *rrset, apply_ctx_t *ctx)
92 {
93 if (node == NULL) {
94 // Node does not exist, cannot remove anything.
95 can_log_rrset(rrset, 0, ctx, true);
96 return false;
97 }
98
99 const knot_rdataset_t *node_rrs = node_rdataset(node, rrset->type);
100 if (node_rrs == NULL) {
101 // Node does not have this type at all.
102 can_log_rrset(rrset, 0, ctx, true);
103 return false;
104 }
105
106 knot_rdata_t *rr_cmp = rrset->rrs.rdata;
107 for (uint16_t i = 0; i < rrset->rrs.count; ++i) {
108 if (!knot_rdataset_member(node_rrs, rr_cmp)) {
109 // At least one RR doesnt' match.
110 can_log_rrset(rrset, i, ctx, true);
111 return false;
112 }
113 rr_cmp = knot_rdataset_next(rr_cmp);
114 }
115
116 return true;
117 }
118
119 /*! \brief Returns true if given RR is not present in node and can be added. */
can_add(const zone_node_t * node,const knot_rrset_t * rrset,apply_ctx_t * ctx)120 static bool can_add(const zone_node_t *node, const knot_rrset_t *rrset, apply_ctx_t *ctx)
121 {
122 if (node == NULL) {
123 // Node does not exist, can add anything.
124 return true;
125 }
126 const knot_rdataset_t *node_rrs = node_rdataset(node, rrset->type);
127 if (node_rrs == NULL) {
128 // Node does not have this type at all.
129 return true;
130 }
131
132 knot_rdata_t *rr_cmp = rrset->rrs.rdata;
133 for (uint16_t i = 0; i < rrset->rrs.count; ++i) {
134 if (knot_rdataset_member(node_rrs, rr_cmp)) {
135 // No RR must match.
136 can_log_rrset(rrset, i, ctx, false);
137 return false;
138 }
139 rr_cmp = knot_rdataset_next(rr_cmp);
140 }
141
142 return true;
143 }
144
apply_init_ctx(apply_ctx_t * ctx,zone_contents_t * contents,uint32_t flags)145 int apply_init_ctx(apply_ctx_t *ctx, zone_contents_t *contents, uint32_t flags)
146 {
147 if (ctx == NULL) {
148 return KNOT_EINVAL;
149 }
150
151 ctx->contents = contents;
152
153 ctx->node_ptrs = zone_tree_create(true);
154 if (ctx->node_ptrs == NULL) {
155 return KNOT_ENOMEM;
156 }
157 ctx->node_ptrs->flags = contents->nodes->flags;
158
159 ctx->nsec3_ptrs = zone_tree_create(true);
160 if (ctx->nsec3_ptrs == NULL) {
161 zone_tree_free(&ctx->node_ptrs);
162 return KNOT_ENOMEM;
163 }
164 ctx->nsec3_ptrs->flags = contents->nodes->flags;
165
166 ctx->adjust_ptrs = zone_tree_create(true);
167 if (ctx->adjust_ptrs == NULL) {
168 zone_tree_free(&ctx->nsec3_ptrs);
169 zone_tree_free(&ctx->node_ptrs);
170 return KNOT_ENOMEM;
171 }
172 ctx->adjust_ptrs->flags = contents->nodes->flags;
173
174 ctx->flags = flags;
175
176 return KNOT_EOK;
177 }
178
add_node_cb(const knot_dname_t * owner,void * ctx)179 static zone_node_t *add_node_cb(const knot_dname_t *owner, void *ctx)
180 {
181 zone_tree_t *tree = ctx;
182 zone_node_t *node = zone_tree_get(tree, owner);
183 if (node == NULL) {
184 node = node_new_for_tree(owner, tree, NULL);
185 } else {
186 node->flags &= ~NODE_FLAGS_DELETED;
187 }
188 return node;
189 }
190
apply_add_rr(apply_ctx_t * ctx,const knot_rrset_t * rr)191 int apply_add_rr(apply_ctx_t *ctx, const knot_rrset_t *rr)
192 {
193 zone_contents_t *contents = ctx->contents;
194 bool nsec3rel = knot_rrset_is_nsec3rel(rr);
195 zone_tree_t *ptrs = nsec3rel ? ctx->nsec3_ptrs : ctx->node_ptrs;
196 zone_tree_t *tree = zone_contents_tree_for_rr(contents, rr);
197 if (tree == NULL) {
198 return KNOT_ENOMEM;
199 }
200
201 // Get or create node with this owner, search changes first
202 zone_node_t *node = NULL;
203 int ret = zone_tree_add_node(tree, contents->apex, rr->owner, add_node_cb, ptrs, &node);
204 if (ret != KNOT_EOK) {
205 return ret;
206 }
207
208 if (!can_add(node, rr, ctx)) {
209 return (ctx->flags & APPLY_STRICT) ? KNOT_EISRECORD : KNOT_EOK;
210 }
211
212 ret = zone_tree_insert_with_parents(ptrs, node, nsec3rel);
213 if (ret != KNOT_EOK) {
214 return ret;
215 }
216
217 if (binode_rdata_shared(node, rr->type)) {
218 // Modifying existing RRSet.
219 ret = replace_rdataset_with_copy(node, rr->type);
220 if (ret != KNOT_EOK) {
221 return ret;
222 }
223 }
224
225 // Insert new RR to RRSet, data will be copied.
226 ret = node_add_rrset(node, rr, NULL);
227 if (ret == KNOT_ETTL) {
228 // this shall not happen except applying journal created before this bugfix
229 return KNOT_EOK;
230 }
231 return ret;
232 }
233
apply_remove_rr(apply_ctx_t * ctx,const knot_rrset_t * rr)234 int apply_remove_rr(apply_ctx_t *ctx, const knot_rrset_t *rr)
235 {
236 zone_contents_t *contents = ctx->contents;
237 bool nsec3rel = knot_rrset_is_nsec3rel(rr);
238 zone_tree_t *ptrs = nsec3rel ? ctx->nsec3_ptrs : ctx->node_ptrs;
239 zone_tree_t *tree = zone_contents_tree_for_rr(contents, rr);
240 if (tree == NULL) {
241 return KNOT_ENOMEM;
242 }
243
244 // Find node for this owner
245 zone_node_t *node = zone_contents_find_node_for_rr(contents, rr);
246 if (!can_remove(node, rr, ctx)) {
247 return (ctx->flags & APPLY_STRICT) ? KNOT_ENORECORD : KNOT_EOK;
248 }
249
250 int ret = zone_tree_insert_with_parents(ptrs, node, nsec3rel);
251 if (ret != KNOT_EOK) {
252 return ret;
253 }
254
255 if (binode_rdata_shared(node, rr->type)) {
256 ret = replace_rdataset_with_copy(node, rr->type);
257 if (ret != KNOT_EOK) {
258 return ret;
259 }
260 }
261
262 ret = node_remove_rrset(node, rr, NULL);
263 if (ret != KNOT_EOK) {
264 clear_new_rrs(node, rr->type);
265 return ret;
266 }
267
268 if (node->rrset_count == 0 && node->children == 0 && node != contents->apex) {
269 zone_tree_del_node(tree, node, false);
270 }
271
272 return KNOT_EOK;
273 }
274
apply_replace_soa(apply_ctx_t * ctx,const knot_rrset_t * rr)275 int apply_replace_soa(apply_ctx_t *ctx, const knot_rrset_t *rr)
276 {
277 zone_contents_t *contents = ctx->contents;
278
279 if (!knot_dname_is_equal(rr->owner, contents->apex->owner)) {
280 return KNOT_EDENIED;
281 }
282
283 knot_rrset_t old_soa = node_rrset(contents->apex, KNOT_RRTYPE_SOA);
284
285 int ret = apply_remove_rr(ctx, &old_soa);
286 if (ret != KNOT_EOK) {
287 return ret;
288 }
289
290 // Check for SOA with proper serial but different rdata.
291 if (node_rrtype_exists(contents->apex, KNOT_RRTYPE_SOA)) {
292 return KNOT_ESOAINVAL;
293 }
294
295 return apply_add_rr(ctx, rr);
296 }
297
apply_cleanup(apply_ctx_t * ctx)298 void apply_cleanup(apply_ctx_t *ctx)
299 {
300 if (ctx == NULL) {
301 return;
302 }
303
304 if (ctx->flags & APPLY_UNIFY_FULL) {
305 zone_trees_unify_binodes(ctx->contents->nodes, ctx->contents->nsec3_nodes, true);
306 } else {
307 zone_trees_unify_binodes(ctx->adjust_ptrs, NULL, false); // beware there might be duplicities in ctx->adjust_ptrs and ctx->node_ptrs, so we don't free here
308 zone_trees_unify_binodes(ctx->node_ptrs, ctx->nsec3_ptrs, true);
309 }
310
311 zone_tree_free(&ctx->node_ptrs);
312 zone_tree_free(&ctx->nsec3_ptrs);
313 zone_tree_free(&ctx->adjust_ptrs);
314
315 if (ctx->cow_mutex != NULL) {
316 knot_sem_post(ctx->cow_mutex);
317 }
318 }
319
apply_rollback(apply_ctx_t * ctx)320 void apply_rollback(apply_ctx_t *ctx)
321 {
322 if (ctx == NULL) {
323 return;
324 }
325
326 if (ctx->node_ptrs != NULL) {
327 ctx->node_ptrs->flags ^= ZONE_TREE_BINO_SECOND;
328 }
329 if (ctx->nsec3_ptrs != NULL) {
330 ctx->nsec3_ptrs->flags ^= ZONE_TREE_BINO_SECOND;
331 }
332 zone_trees_unify_binodes(ctx->node_ptrs, ctx->nsec3_ptrs, true);
333
334 zone_tree_free(&ctx->node_ptrs);
335 zone_tree_free(&ctx->nsec3_ptrs);
336 zone_tree_free(&ctx->adjust_ptrs);
337
338 trie_cow_rollback(ctx->contents->nodes->cow, NULL, NULL);
339 ctx->contents->nodes->cow = NULL;
340 if (ctx->contents->nsec3_nodes != NULL && ctx->contents->nsec3_nodes->cow != NULL) {
341 trie_cow_rollback(ctx->contents->nsec3_nodes->cow, NULL, NULL);
342 ctx->contents->nsec3_nodes->cow = NULL;
343 } else if (ctx->contents->nsec3_nodes != NULL) {
344 zone_tree_free(&ctx->contents->nsec3_nodes);
345 ctx->contents->nsec3_nodes = NULL;
346 }
347
348 free(ctx->contents->nodes);
349 free(ctx->contents->nsec3_nodes);
350
351 dnssec_nsec3_params_free(&ctx->contents->nsec3_params);
352
353 free(ctx->contents);
354
355 if (ctx->cow_mutex != NULL) {
356 knot_sem_post(ctx->cow_mutex);
357 }
358 }
359
update_free_zone(zone_contents_t * contents)360 void update_free_zone(zone_contents_t *contents)
361 {
362 if (contents == NULL) {
363 return;
364 }
365
366 trie_cow_commit(contents->nodes->cow, NULL, NULL);
367 contents->nodes->cow = NULL;
368 if (contents->nsec3_nodes != NULL && contents->nsec3_nodes->cow != NULL) {
369 trie_cow_commit(contents->nsec3_nodes->cow, NULL, NULL);
370 contents->nsec3_nodes->cow = NULL;
371 }
372
373 free(contents->nodes);
374 free(contents->nsec3_nodes);
375
376 dnssec_nsec3_params_free(&contents->nsec3_params);
377
378 free(contents);
379 }
380