1 /* $OpenBSD: krl.c,v 1.60 2025/02/18 08:02:48 djm Exp $ */ 2 /* 3 * Copyright (c) 2012 Damien Miller <djm@mindrot.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include "includes.h" 19 20 #include <sys/types.h> 21 #include <openbsd-compat/sys-tree.h> 22 #include <openbsd-compat/sys-queue.h> 23 24 #include <errno.h> 25 #include <fcntl.h> 26 #include <limits.h> 27 #include <stdlib.h> 28 #include <string.h> 29 #include <time.h> 30 #include <unistd.h> 31 32 #include "sshbuf.h" 33 #include "ssherr.h" 34 #include "sshkey.h" 35 #include "authfile.h" 36 #include "misc.h" 37 #include "log.h" 38 #include "digest.h" 39 #include "bitmap.h" 40 #include "utf8.h" 41 42 #include "krl.h" 43 44 /* #define DEBUG_KRL */ 45 #ifdef DEBUG_KRL 46 # define KRL_DBG(x) debug3_f x 47 #else 48 # define KRL_DBG(x) 49 #endif 50 51 /* 52 * Trees of revoked serial numbers, key IDs and keys. This allows 53 * quick searching, querying and producing lists in canonical order. 54 */ 55 56 /* Tree of serial numbers. XXX make smarter: really need a real sparse bitmap */ 57 struct revoked_serial { 58 u_int64_t lo, hi; 59 RB_ENTRY(revoked_serial) tree_entry; 60 }; 61 static int serial_cmp(struct revoked_serial *a, struct revoked_serial *b); 62 RB_HEAD(revoked_serial_tree, revoked_serial); 63 RB_GENERATE_STATIC(revoked_serial_tree, revoked_serial, tree_entry, serial_cmp) 64 65 /* Tree of key IDs */ 66 struct revoked_key_id { 67 char *key_id; 68 RB_ENTRY(revoked_key_id) tree_entry; 69 }; 70 static int key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b); 71 RB_HEAD(revoked_key_id_tree, revoked_key_id); 72 RB_GENERATE_STATIC(revoked_key_id_tree, revoked_key_id, tree_entry, key_id_cmp) 73 74 /* Tree of blobs (used for keys and fingerprints) */ 75 struct revoked_blob { 76 u_char *blob; 77 size_t len; 78 RB_ENTRY(revoked_blob) tree_entry; 79 }; 80 static int blob_cmp(struct revoked_blob *a, struct revoked_blob *b); 81 RB_HEAD(revoked_blob_tree, revoked_blob); 82 RB_GENERATE_STATIC(revoked_blob_tree, revoked_blob, tree_entry, blob_cmp) 83 84 /* Tracks revoked certs for a single CA */ 85 struct revoked_certs { 86 struct sshkey *ca_key; 87 struct revoked_serial_tree revoked_serials; 88 struct revoked_key_id_tree revoked_key_ids; 89 TAILQ_ENTRY(revoked_certs) entry; 90 }; 91 TAILQ_HEAD(revoked_certs_list, revoked_certs); 92 93 struct ssh_krl { 94 u_int64_t krl_version; 95 u_int64_t generated_date; 96 u_int64_t flags; 97 char *comment; 98 struct revoked_blob_tree revoked_keys; 99 struct revoked_blob_tree revoked_sha1s; 100 struct revoked_blob_tree revoked_sha256s; 101 struct revoked_certs_list revoked_certs; 102 }; 103 104 /* Return equal if a and b overlap */ 105 static int 106 serial_cmp(struct revoked_serial *a, struct revoked_serial *b) 107 { 108 if (a->hi >= b->lo && a->lo <= b->hi) 109 return 0; 110 return a->lo < b->lo ? -1 : 1; 111 } 112 113 static int 114 key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b) 115 { 116 return strcmp(a->key_id, b->key_id); 117 } 118 119 static int 120 blob_cmp(struct revoked_blob *a, struct revoked_blob *b) 121 { 122 int r; 123 124 if (a->len != b->len) { 125 if ((r = memcmp(a->blob, b->blob, MINIMUM(a->len, b->len))) != 0) 126 return r; 127 return a->len > b->len ? 1 : -1; 128 } else 129 return memcmp(a->blob, b->blob, a->len); 130 } 131 132 struct ssh_krl * 133 ssh_krl_init(void) 134 { 135 struct ssh_krl *krl; 136 137 if ((krl = calloc(1, sizeof(*krl))) == NULL) 138 return NULL; 139 RB_INIT(&krl->revoked_keys); 140 RB_INIT(&krl->revoked_sha1s); 141 RB_INIT(&krl->revoked_sha256s); 142 TAILQ_INIT(&krl->revoked_certs); 143 return krl; 144 } 145 146 static void 147 revoked_certs_free(struct revoked_certs *rc) 148 { 149 struct revoked_serial *rs, *trs; 150 struct revoked_key_id *rki, *trki; 151 152 RB_FOREACH_SAFE(rs, revoked_serial_tree, &rc->revoked_serials, trs) { 153 RB_REMOVE(revoked_serial_tree, &rc->revoked_serials, rs); 154 free(rs); 155 } 156 RB_FOREACH_SAFE(rki, revoked_key_id_tree, &rc->revoked_key_ids, trki) { 157 RB_REMOVE(revoked_key_id_tree, &rc->revoked_key_ids, rki); 158 free(rki->key_id); 159 free(rki); 160 } 161 sshkey_free(rc->ca_key); 162 } 163 164 void 165 ssh_krl_free(struct ssh_krl *krl) 166 { 167 struct revoked_blob *rb, *trb; 168 struct revoked_certs *rc, *trc; 169 170 if (krl == NULL) 171 return; 172 173 free(krl->comment); 174 RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_keys, trb) { 175 RB_REMOVE(revoked_blob_tree, &krl->revoked_keys, rb); 176 free(rb->blob); 177 free(rb); 178 } 179 RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_sha1s, trb) { 180 RB_REMOVE(revoked_blob_tree, &krl->revoked_sha1s, rb); 181 free(rb->blob); 182 free(rb); 183 } 184 RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_sha256s, trb) { 185 RB_REMOVE(revoked_blob_tree, &krl->revoked_sha256s, rb); 186 free(rb->blob); 187 free(rb); 188 } 189 TAILQ_FOREACH_SAFE(rc, &krl->revoked_certs, entry, trc) { 190 TAILQ_REMOVE(&krl->revoked_certs, rc, entry); 191 revoked_certs_free(rc); 192 } 193 free(krl); 194 } 195 196 void 197 ssh_krl_set_version(struct ssh_krl *krl, u_int64_t version) 198 { 199 krl->krl_version = version; 200 } 201 202 int 203 ssh_krl_set_comment(struct ssh_krl *krl, const char *comment) 204 { 205 free(krl->comment); 206 if ((krl->comment = strdup(comment)) == NULL) 207 return SSH_ERR_ALLOC_FAIL; 208 return 0; 209 } 210 211 /* 212 * Find the revoked_certs struct for a CA key. If allow_create is set then 213 * create a new one in the tree if one did not exist already. 214 */ 215 static int 216 revoked_certs_for_ca_key(struct ssh_krl *krl, const struct sshkey *ca_key, 217 struct revoked_certs **rcp, int allow_create) 218 { 219 struct revoked_certs *rc; 220 int r; 221 222 *rcp = NULL; 223 TAILQ_FOREACH(rc, &krl->revoked_certs, entry) { 224 if ((ca_key == NULL && rc->ca_key == NULL) || 225 sshkey_equal(rc->ca_key, ca_key)) { 226 *rcp = rc; 227 return 0; 228 } 229 } 230 if (!allow_create) 231 return 0; 232 /* If this CA doesn't exist in the list then add it now */ 233 if ((rc = calloc(1, sizeof(*rc))) == NULL) 234 return SSH_ERR_ALLOC_FAIL; 235 if (ca_key == NULL) 236 rc->ca_key = NULL; 237 else if ((r = sshkey_from_private(ca_key, &rc->ca_key)) != 0) { 238 free(rc); 239 return r; 240 } 241 RB_INIT(&rc->revoked_serials); 242 RB_INIT(&rc->revoked_key_ids); 243 TAILQ_INSERT_TAIL(&krl->revoked_certs, rc, entry); 244 KRL_DBG(("new CA %s", ca_key == NULL ? "*" : sshkey_type(ca_key))); 245 *rcp = rc; 246 return 0; 247 } 248 249 static int 250 insert_serial_range(struct revoked_serial_tree *rt, u_int64_t lo, u_int64_t hi) 251 { 252 struct revoked_serial rs, *ers, *crs, *irs; 253 254 KRL_DBG(("insert %llu:%llu", lo, hi)); 255 memset(&rs, 0, sizeof(rs)); 256 rs.lo = lo; 257 rs.hi = hi; 258 ers = RB_NFIND(revoked_serial_tree, rt, &rs); 259 if (ers == NULL || serial_cmp(ers, &rs) != 0) { 260 /* No entry matches. Just insert */ 261 if ((irs = malloc(sizeof(rs))) == NULL) 262 return SSH_ERR_ALLOC_FAIL; 263 memcpy(irs, &rs, sizeof(*irs)); 264 ers = RB_INSERT(revoked_serial_tree, rt, irs); 265 if (ers != NULL) { 266 KRL_DBG(("bad: ers != NULL")); 267 /* Shouldn't happen */ 268 free(irs); 269 return SSH_ERR_INTERNAL_ERROR; 270 } 271 ers = irs; 272 } else { 273 KRL_DBG(("overlap found %llu:%llu", ers->lo, ers->hi)); 274 /* 275 * The inserted entry overlaps an existing one. Grow the 276 * existing entry. 277 */ 278 if (ers->lo > lo) 279 ers->lo = lo; 280 if (ers->hi < hi) 281 ers->hi = hi; 282 } 283 284 /* 285 * The inserted or revised range might overlap or abut adjacent ones; 286 * coalesce as necessary. 287 */ 288 289 /* Check predecessors */ 290 while ((crs = RB_PREV(revoked_serial_tree, rt, ers)) != NULL) { 291 KRL_DBG(("pred %llu:%llu", crs->lo, crs->hi)); 292 if (ers->lo != 0 && crs->hi < ers->lo - 1) 293 break; 294 /* This entry overlaps. */ 295 if (crs->lo < ers->lo) { 296 ers->lo = crs->lo; 297 KRL_DBG(("pred extend %llu:%llu", ers->lo, ers->hi)); 298 } 299 RB_REMOVE(revoked_serial_tree, rt, crs); 300 free(crs); 301 } 302 /* Check successors */ 303 while ((crs = RB_NEXT(revoked_serial_tree, rt, ers)) != NULL) { 304 KRL_DBG(("succ %llu:%llu", crs->lo, crs->hi)); 305 if (ers->hi != (u_int64_t)-1 && crs->lo > ers->hi + 1) 306 break; 307 /* This entry overlaps. */ 308 if (crs->hi > ers->hi) { 309 ers->hi = crs->hi; 310 KRL_DBG(("succ extend %llu:%llu", ers->lo, ers->hi)); 311 } 312 RB_REMOVE(revoked_serial_tree, rt, crs); 313 free(crs); 314 } 315 KRL_DBG(("done, final %llu:%llu", ers->lo, ers->hi)); 316 return 0; 317 } 318 319 int 320 ssh_krl_revoke_cert_by_serial(struct ssh_krl *krl, const struct sshkey *ca_key, 321 u_int64_t serial) 322 { 323 return ssh_krl_revoke_cert_by_serial_range(krl, ca_key, serial, serial); 324 } 325 326 int 327 ssh_krl_revoke_cert_by_serial_range(struct ssh_krl *krl, 328 const struct sshkey *ca_key, u_int64_t lo, u_int64_t hi) 329 { 330 struct revoked_certs *rc; 331 int r; 332 333 if (lo > hi || lo == 0) 334 return SSH_ERR_INVALID_ARGUMENT; 335 if ((r = revoked_certs_for_ca_key(krl, ca_key, &rc, 1)) != 0) 336 return r; 337 return insert_serial_range(&rc->revoked_serials, lo, hi); 338 } 339 340 int 341 ssh_krl_revoke_cert_by_key_id(struct ssh_krl *krl, const struct sshkey *ca_key, 342 const char *key_id) 343 { 344 struct revoked_key_id *rki, *erki; 345 struct revoked_certs *rc; 346 int r; 347 348 if ((r = revoked_certs_for_ca_key(krl, ca_key, &rc, 1)) != 0) 349 return r; 350 351 KRL_DBG(("revoke %s", key_id)); 352 if ((rki = calloc(1, sizeof(*rki))) == NULL || 353 (rki->key_id = strdup(key_id)) == NULL) { 354 free(rki); 355 return SSH_ERR_ALLOC_FAIL; 356 } 357 erki = RB_INSERT(revoked_key_id_tree, &rc->revoked_key_ids, rki); 358 if (erki != NULL) { 359 free(rki->key_id); 360 free(rki); 361 } 362 return 0; 363 } 364 365 /* Convert "key" to a public key blob without any certificate information */ 366 static int 367 plain_key_blob(const struct sshkey *key, u_char **blob, size_t *blen) 368 { 369 struct sshkey *kcopy; 370 int r; 371 372 if ((r = sshkey_from_private(key, &kcopy)) != 0) 373 return r; 374 if (sshkey_is_cert(kcopy)) { 375 if ((r = sshkey_drop_cert(kcopy)) != 0) { 376 sshkey_free(kcopy); 377 return r; 378 } 379 } 380 r = sshkey_to_blob(kcopy, blob, blen); 381 sshkey_free(kcopy); 382 return r; 383 } 384 385 /* Revoke a key blob. Ownership of blob is transferred to the tree */ 386 static int 387 revoke_blob(struct revoked_blob_tree *rbt, u_char *blob, size_t len) 388 { 389 struct revoked_blob *rb, *erb; 390 391 if ((rb = calloc(1, sizeof(*rb))) == NULL) 392 return SSH_ERR_ALLOC_FAIL; 393 rb->blob = blob; 394 rb->len = len; 395 erb = RB_INSERT(revoked_blob_tree, rbt, rb); 396 if (erb != NULL) { 397 free(rb->blob); 398 free(rb); 399 } 400 return 0; 401 } 402 403 int 404 ssh_krl_revoke_key_explicit(struct ssh_krl *krl, const struct sshkey *key) 405 { 406 u_char *blob; 407 size_t len; 408 int r; 409 410 debug3_f("revoke type %s", sshkey_type(key)); 411 if ((r = plain_key_blob(key, &blob, &len)) != 0) 412 return r; 413 return revoke_blob(&krl->revoked_keys, blob, len); 414 } 415 416 static int 417 revoke_by_hash(struct revoked_blob_tree *target, const u_char *p, size_t len) 418 { 419 u_char *blob; 420 int r; 421 422 /* need to copy hash, as revoke_blob steals ownership */ 423 if ((blob = malloc(len)) == NULL) 424 return SSH_ERR_SYSTEM_ERROR; 425 memcpy(blob, p, len); 426 if ((r = revoke_blob(target, blob, len)) != 0) { 427 free(blob); 428 return r; 429 } 430 return 0; 431 } 432 433 int 434 ssh_krl_revoke_key_sha1(struct ssh_krl *krl, const u_char *p, size_t len) 435 { 436 debug3_f("revoke by sha1"); 437 if (len != 20) 438 return SSH_ERR_INVALID_FORMAT; 439 return revoke_by_hash(&krl->revoked_sha1s, p, len); 440 } 441 442 int 443 ssh_krl_revoke_key_sha256(struct ssh_krl *krl, const u_char *p, size_t len) 444 { 445 debug3_f("revoke by sha256"); 446 if (len != 32) 447 return SSH_ERR_INVALID_FORMAT; 448 return revoke_by_hash(&krl->revoked_sha256s, p, len); 449 } 450 451 int 452 ssh_krl_revoke_key(struct ssh_krl *krl, const struct sshkey *key) 453 { 454 /* XXX replace with SHA256? */ 455 if (!sshkey_is_cert(key)) 456 return ssh_krl_revoke_key_explicit(krl, key); 457 458 if (key->cert->serial == 0) { 459 return ssh_krl_revoke_cert_by_key_id(krl, 460 key->cert->signature_key, 461 key->cert->key_id); 462 } else { 463 return ssh_krl_revoke_cert_by_serial(krl, 464 key->cert->signature_key, 465 key->cert->serial); 466 } 467 } 468 469 /* 470 * Select the most compact section type to emit next in a KRL based on 471 * the current section type, the run length of contiguous revoked serial 472 * numbers and the gaps from the last and to the next revoked serial. 473 * Applies a mostly-accurate bit cost model to select the section type 474 * that will minimise the size of the resultant KRL. 475 */ 476 static int 477 choose_next_state(int current_state, u_int64_t contig, int final, 478 u_int64_t last_gap, u_int64_t next_gap, int *force_new_section) 479 { 480 int new_state; 481 u_int64_t cost, cost_list, cost_range, cost_bitmap, cost_bitmap_restart; 482 483 /* 484 * Avoid unsigned overflows. 485 * The limits are high enough to avoid confusing the calculations. 486 */ 487 contig = MINIMUM(contig, 1ULL<<31); 488 last_gap = MINIMUM(last_gap, 1ULL<<31); 489 next_gap = MINIMUM(next_gap, 1ULL<<31); 490 491 /* 492 * Calculate the cost to switch from the current state to candidates. 493 * NB. range sections only ever contain a single range, so their 494 * switching cost is independent of the current_state. 495 */ 496 cost_list = cost_bitmap = cost_bitmap_restart = 0; 497 cost_range = 8; 498 switch (current_state) { 499 case KRL_SECTION_CERT_SERIAL_LIST: 500 cost_bitmap_restart = cost_bitmap = 8 + 64; 501 break; 502 case KRL_SECTION_CERT_SERIAL_BITMAP: 503 cost_list = 8; 504 cost_bitmap_restart = 8 + 64; 505 break; 506 case KRL_SECTION_CERT_SERIAL_RANGE: 507 case 0: 508 cost_bitmap_restart = cost_bitmap = 8 + 64; 509 cost_list = 8; 510 } 511 512 /* Estimate base cost in bits of each section type */ 513 cost_list += 64 * contig + (final ? 0 : 8+64); 514 cost_range += (2 * 64) + (final ? 0 : 8+64); 515 cost_bitmap += last_gap + contig + (final ? 0 : MINIMUM(next_gap, 8+64)); 516 cost_bitmap_restart += contig + (final ? 0 : MINIMUM(next_gap, 8+64)); 517 518 /* Convert to byte costs for actual comparison */ 519 cost_list = (cost_list + 7) / 8; 520 cost_bitmap = (cost_bitmap + 7) / 8; 521 cost_bitmap_restart = (cost_bitmap_restart + 7) / 8; 522 cost_range = (cost_range + 7) / 8; 523 524 /* Now pick the best choice */ 525 *force_new_section = 0; 526 new_state = KRL_SECTION_CERT_SERIAL_BITMAP; 527 cost = cost_bitmap; 528 if (cost_range < cost) { 529 new_state = KRL_SECTION_CERT_SERIAL_RANGE; 530 cost = cost_range; 531 } 532 if (cost_list < cost) { 533 new_state = KRL_SECTION_CERT_SERIAL_LIST; 534 cost = cost_list; 535 } 536 if (cost_bitmap_restart < cost) { 537 new_state = KRL_SECTION_CERT_SERIAL_BITMAP; 538 *force_new_section = 1; 539 cost = cost_bitmap_restart; 540 } 541 KRL_DBG(("contig %llu last_gap %llu next_gap %llu final %d, costs:" 542 "list %llu range %llu bitmap %llu new bitmap %llu, " 543 "selected 0x%02x%s", (long long unsigned)contig, 544 (long long unsigned)last_gap, (long long unsigned)next_gap, final, 545 (long long unsigned)cost_list, (long long unsigned)cost_range, 546 (long long unsigned)cost_bitmap, 547 (long long unsigned)cost_bitmap_restart, new_state, 548 *force_new_section ? " restart" : "")); 549 return new_state; 550 } 551 552 static int 553 put_bitmap(struct sshbuf *buf, struct bitmap *bitmap) 554 { 555 size_t len; 556 u_char *blob; 557 int r; 558 559 len = bitmap_nbytes(bitmap); 560 if ((blob = malloc(len)) == NULL) 561 return SSH_ERR_ALLOC_FAIL; 562 if (bitmap_to_string(bitmap, blob, len) != 0) { 563 free(blob); 564 return SSH_ERR_INTERNAL_ERROR; 565 } 566 r = sshbuf_put_bignum2_bytes(buf, blob, len); 567 free(blob); 568 return r; 569 } 570 571 /* Generate a KRL_SECTION_CERTIFICATES KRL section */ 572 static int 573 revoked_certs_generate(struct revoked_certs *rc, struct sshbuf *buf) 574 { 575 int final, force_new_sect, r = SSH_ERR_INTERNAL_ERROR; 576 u_int64_t i, contig, gap, last = 0, bitmap_start = 0; 577 struct revoked_serial *rs, *nrs; 578 struct revoked_key_id *rki; 579 int next_state, state = 0; 580 struct sshbuf *sect; 581 struct bitmap *bitmap = NULL; 582 583 if ((sect = sshbuf_new()) == NULL) 584 return SSH_ERR_ALLOC_FAIL; 585 586 /* Store the header: optional CA scope key, reserved */ 587 if (rc->ca_key == NULL) { 588 if ((r = sshbuf_put_string(buf, NULL, 0)) != 0) 589 goto out; 590 } else { 591 if ((r = sshkey_puts(rc->ca_key, buf)) != 0) 592 goto out; 593 } 594 if ((r = sshbuf_put_string(buf, NULL, 0)) != 0) 595 goto out; 596 597 /* Store the revoked serials. */ 598 for (rs = RB_MIN(revoked_serial_tree, &rc->revoked_serials); 599 rs != NULL; 600 rs = RB_NEXT(revoked_serial_tree, &rc->revoked_serials, rs)) { 601 KRL_DBG(("serial %llu:%llu state 0x%02x", 602 (long long unsigned)rs->lo, (long long unsigned)rs->hi, 603 state)); 604 605 /* Check contiguous length and gap to next section (if any) */ 606 nrs = RB_NEXT(revoked_serial_tree, &rc->revoked_serials, rs); 607 final = nrs == NULL; 608 gap = nrs == NULL ? 0 : nrs->lo - rs->hi; 609 contig = 1 + (rs->hi - rs->lo); 610 611 /* Choose next state based on these */ 612 next_state = choose_next_state(state, contig, final, 613 state == 0 ? 0 : rs->lo - last, gap, &force_new_sect); 614 615 /* 616 * If the current section is a range section or has a different 617 * type to the next section, then finish it off now. 618 */ 619 if (state != 0 && (force_new_sect || next_state != state || 620 state == KRL_SECTION_CERT_SERIAL_RANGE)) { 621 KRL_DBG(("finish state 0x%02x", state)); 622 switch (state) { 623 case KRL_SECTION_CERT_SERIAL_LIST: 624 case KRL_SECTION_CERT_SERIAL_RANGE: 625 break; 626 case KRL_SECTION_CERT_SERIAL_BITMAP: 627 if ((r = put_bitmap(sect, bitmap)) != 0) 628 goto out; 629 bitmap_free(bitmap); 630 bitmap = NULL; 631 break; 632 } 633 if ((r = sshbuf_put_u8(buf, state)) != 0 || 634 (r = sshbuf_put_stringb(buf, sect)) != 0) 635 goto out; 636 sshbuf_reset(sect); 637 } 638 639 /* If we are starting a new section then prepare it now */ 640 if (next_state != state || force_new_sect) { 641 KRL_DBG(("start state 0x%02x", 642 next_state)); 643 state = next_state; 644 sshbuf_reset(sect); 645 switch (state) { 646 case KRL_SECTION_CERT_SERIAL_LIST: 647 case KRL_SECTION_CERT_SERIAL_RANGE: 648 break; 649 case KRL_SECTION_CERT_SERIAL_BITMAP: 650 if ((bitmap = bitmap_new()) == NULL) { 651 r = SSH_ERR_ALLOC_FAIL; 652 goto out; 653 } 654 bitmap_start = rs->lo; 655 if ((r = sshbuf_put_u64(sect, 656 bitmap_start)) != 0) 657 goto out; 658 break; 659 } 660 } 661 662 /* Perform section-specific processing */ 663 switch (state) { 664 case KRL_SECTION_CERT_SERIAL_LIST: 665 for (i = 0; i < contig; i++) { 666 if ((r = sshbuf_put_u64(sect, rs->lo + i)) != 0) 667 goto out; 668 } 669 break; 670 case KRL_SECTION_CERT_SERIAL_RANGE: 671 if ((r = sshbuf_put_u64(sect, rs->lo)) != 0 || 672 (r = sshbuf_put_u64(sect, rs->hi)) != 0) 673 goto out; 674 break; 675 case KRL_SECTION_CERT_SERIAL_BITMAP: 676 if (rs->lo - bitmap_start > INT_MAX) { 677 r = SSH_ERR_INVALID_FORMAT; 678 error_f("insane bitmap gap"); 679 goto out; 680 } 681 for (i = 0; i < contig; i++) { 682 if (bitmap_set_bit(bitmap, 683 rs->lo + i - bitmap_start) != 0) { 684 r = SSH_ERR_ALLOC_FAIL; 685 goto out; 686 } 687 } 688 break; 689 } 690 last = rs->hi; 691 } 692 /* Flush the remaining section, if any */ 693 if (state != 0) { 694 KRL_DBG(("serial final flush for state 0x%02x", state)); 695 switch (state) { 696 case KRL_SECTION_CERT_SERIAL_LIST: 697 case KRL_SECTION_CERT_SERIAL_RANGE: 698 break; 699 case KRL_SECTION_CERT_SERIAL_BITMAP: 700 if ((r = put_bitmap(sect, bitmap)) != 0) 701 goto out; 702 bitmap_free(bitmap); 703 bitmap = NULL; 704 break; 705 } 706 if ((r = sshbuf_put_u8(buf, state)) != 0 || 707 (r = sshbuf_put_stringb(buf, sect)) != 0) 708 goto out; 709 } 710 KRL_DBG(("serial done ")); 711 712 /* Now output a section for any revocations by key ID */ 713 sshbuf_reset(sect); 714 RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) { 715 KRL_DBG(("key ID %s", rki->key_id)); 716 if ((r = sshbuf_put_cstring(sect, rki->key_id)) != 0) 717 goto out; 718 } 719 if (sshbuf_len(sect) != 0) { 720 if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERT_KEY_ID)) != 0 || 721 (r = sshbuf_put_stringb(buf, sect)) != 0) 722 goto out; 723 } 724 r = 0; 725 out: 726 bitmap_free(bitmap); 727 sshbuf_free(sect); 728 return r; 729 } 730 731 int 732 ssh_krl_to_blob(struct ssh_krl *krl, struct sshbuf *buf) 733 { 734 int r = SSH_ERR_INTERNAL_ERROR; 735 struct revoked_certs *rc; 736 struct revoked_blob *rb; 737 struct sshbuf *sect; 738 u_char *sblob = NULL; 739 740 if (krl->generated_date == 0) 741 krl->generated_date = time(NULL); 742 743 if ((sect = sshbuf_new()) == NULL) 744 return SSH_ERR_ALLOC_FAIL; 745 746 /* Store the header */ 747 if ((r = sshbuf_put(buf, KRL_MAGIC, sizeof(KRL_MAGIC) - 1)) != 0 || 748 (r = sshbuf_put_u32(buf, KRL_FORMAT_VERSION)) != 0 || 749 (r = sshbuf_put_u64(buf, krl->krl_version)) != 0 || 750 (r = sshbuf_put_u64(buf, krl->generated_date)) != 0 || 751 (r = sshbuf_put_u64(buf, krl->flags)) != 0 || 752 (r = sshbuf_put_string(buf, NULL, 0)) != 0 || 753 (r = sshbuf_put_cstring(buf, krl->comment)) != 0) 754 goto out; 755 756 /* Store sections for revoked certificates */ 757 TAILQ_FOREACH(rc, &krl->revoked_certs, entry) { 758 sshbuf_reset(sect); 759 if ((r = revoked_certs_generate(rc, sect)) != 0) 760 goto out; 761 if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERTIFICATES)) != 0 || 762 (r = sshbuf_put_stringb(buf, sect)) != 0) 763 goto out; 764 } 765 766 /* Finally, output sections for revocations by public key/hash */ 767 sshbuf_reset(sect); 768 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) { 769 KRL_DBG(("key len %zu ", rb->len)); 770 if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0) 771 goto out; 772 } 773 if (sshbuf_len(sect) != 0) { 774 if ((r = sshbuf_put_u8(buf, KRL_SECTION_EXPLICIT_KEY)) != 0 || 775 (r = sshbuf_put_stringb(buf, sect)) != 0) 776 goto out; 777 } 778 sshbuf_reset(sect); 779 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) { 780 KRL_DBG(("hash len %zu ", rb->len)); 781 if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0) 782 goto out; 783 } 784 if (sshbuf_len(sect) != 0) { 785 if ((r = sshbuf_put_u8(buf, 786 KRL_SECTION_FINGERPRINT_SHA1)) != 0 || 787 (r = sshbuf_put_stringb(buf, sect)) != 0) 788 goto out; 789 } 790 sshbuf_reset(sect); 791 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha256s) { 792 KRL_DBG(("hash len %zu ", rb->len)); 793 if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0) 794 goto out; 795 } 796 if (sshbuf_len(sect) != 0) { 797 if ((r = sshbuf_put_u8(buf, 798 KRL_SECTION_FINGERPRINT_SHA256)) != 0 || 799 (r = sshbuf_put_stringb(buf, sect)) != 0) 800 goto out; 801 } 802 /* success */ 803 r = 0; 804 out: 805 free(sblob); 806 sshbuf_free(sect); 807 return r; 808 } 809 810 static void 811 format_timestamp(u_int64_t timestamp, char *ts, size_t nts) 812 { 813 time_t t; 814 struct tm *tm; 815 816 t = timestamp; 817 tm = localtime(&t); 818 if (tm == NULL) 819 strlcpy(ts, "<INVALID>", nts); 820 else { 821 *ts = '\0'; 822 strftime(ts, nts, "%Y%m%dT%H%M%S", tm); 823 } 824 } 825 826 static int 827 cert_extension_subsection(struct sshbuf *subsect, struct ssh_krl *krl) 828 { 829 int r = SSH_ERR_INTERNAL_ERROR; 830 u_char critical = 1; 831 struct sshbuf *value = NULL; 832 char *name = NULL; 833 834 if ((r = sshbuf_get_cstring(subsect, &name, NULL)) != 0 || 835 (r = sshbuf_get_u8(subsect, &critical)) != 0 || 836 (r = sshbuf_froms(subsect, &value)) != 0) { 837 debug_fr(r, "parse"); 838 error("KRL has invalid certificate extension subsection"); 839 r = SSH_ERR_INVALID_FORMAT; 840 goto out; 841 } 842 if (sshbuf_len(subsect) != 0) { 843 error("KRL has invalid certificate extension subsection: " 844 "trailing data"); 845 r = SSH_ERR_INVALID_FORMAT; 846 goto out; 847 } 848 debug_f("cert extension %s critical %u len %zu", 849 name, critical, sshbuf_len(value)); 850 /* no extensions are currently supported */ 851 if (critical) { 852 error("KRL contains unsupported critical certificate " 853 "subsection \"%s\"", name); 854 r = SSH_ERR_FEATURE_UNSUPPORTED; 855 goto out; 856 } 857 /* success */ 858 r = 0; 859 out: 860 free(name); 861 sshbuf_free(value); 862 return r; 863 } 864 865 static int 866 parse_revoked_certs(struct sshbuf *buf, struct ssh_krl *krl) 867 { 868 int r = SSH_ERR_INTERNAL_ERROR; 869 u_char type; 870 const u_char *blob; 871 size_t blen, nbits; 872 struct sshbuf *subsect = NULL; 873 u_int64_t serial, serial_lo, serial_hi; 874 struct bitmap *bitmap = NULL; 875 char *key_id = NULL; 876 struct sshkey *ca_key = NULL; 877 878 if ((subsect = sshbuf_new()) == NULL) 879 return SSH_ERR_ALLOC_FAIL; 880 881 /* Header: key, reserved */ 882 if ((r = sshbuf_get_string_direct(buf, &blob, &blen)) != 0 || 883 (r = sshbuf_skip_string(buf)) != 0) 884 goto out; 885 if (blen != 0 && (r = sshkey_from_blob(blob, blen, &ca_key)) != 0) 886 goto out; 887 888 while (sshbuf_len(buf) > 0) { 889 sshbuf_free(subsect); 890 subsect = NULL; 891 if ((r = sshbuf_get_u8(buf, &type)) != 0 || 892 (r = sshbuf_froms(buf, &subsect)) != 0) 893 goto out; 894 KRL_DBG(("subsection type 0x%02x", type)); 895 /* sshbuf_dump(subsect, stderr); */ 896 897 switch (type) { 898 case KRL_SECTION_CERT_SERIAL_LIST: 899 while (sshbuf_len(subsect) > 0) { 900 if ((r = sshbuf_get_u64(subsect, &serial)) != 0) 901 goto out; 902 if ((r = ssh_krl_revoke_cert_by_serial(krl, 903 ca_key, serial)) != 0) 904 goto out; 905 } 906 break; 907 case KRL_SECTION_CERT_SERIAL_RANGE: 908 if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 || 909 (r = sshbuf_get_u64(subsect, &serial_hi)) != 0) 910 goto out; 911 if ((r = ssh_krl_revoke_cert_by_serial_range(krl, 912 ca_key, serial_lo, serial_hi)) != 0) 913 goto out; 914 break; 915 case KRL_SECTION_CERT_SERIAL_BITMAP: 916 if ((bitmap = bitmap_new()) == NULL) { 917 r = SSH_ERR_ALLOC_FAIL; 918 goto out; 919 } 920 if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 || 921 (r = sshbuf_get_bignum2_bytes_direct(subsect, 922 &blob, &blen)) != 0) 923 goto out; 924 if (bitmap_from_string(bitmap, blob, blen) != 0) { 925 r = SSH_ERR_INVALID_FORMAT; 926 goto out; 927 } 928 nbits = bitmap_nbits(bitmap); 929 for (serial = 0; serial < (u_int64_t)nbits; serial++) { 930 if (serial > 0 && serial_lo + serial == 0) { 931 error_f("bitmap wraps u64"); 932 r = SSH_ERR_INVALID_FORMAT; 933 goto out; 934 } 935 if (!bitmap_test_bit(bitmap, serial)) 936 continue; 937 if ((r = ssh_krl_revoke_cert_by_serial(krl, 938 ca_key, serial_lo + serial)) != 0) 939 goto out; 940 } 941 bitmap_free(bitmap); 942 bitmap = NULL; 943 break; 944 case KRL_SECTION_CERT_KEY_ID: 945 while (sshbuf_len(subsect) > 0) { 946 if ((r = sshbuf_get_cstring(subsect, 947 &key_id, NULL)) != 0) 948 goto out; 949 if ((r = ssh_krl_revoke_cert_by_key_id(krl, 950 ca_key, key_id)) != 0) 951 goto out; 952 free(key_id); 953 key_id = NULL; 954 } 955 break; 956 case KRL_SECTION_CERT_EXTENSION: 957 if ((r = cert_extension_subsection(subsect, krl)) != 0) 958 goto out; 959 break; 960 default: 961 error("Unsupported KRL certificate section %u", type); 962 r = SSH_ERR_INVALID_FORMAT; 963 goto out; 964 } 965 if (sshbuf_len(subsect) > 0) { 966 error("KRL certificate section contains unparsed data"); 967 r = SSH_ERR_INVALID_FORMAT; 968 goto out; 969 } 970 } 971 972 r = 0; 973 out: 974 if (bitmap != NULL) 975 bitmap_free(bitmap); 976 free(key_id); 977 sshkey_free(ca_key); 978 sshbuf_free(subsect); 979 return r; 980 } 981 982 static int 983 blob_section(struct sshbuf *sect, struct revoked_blob_tree *target_tree, 984 size_t expected_len) 985 { 986 u_char *rdata = NULL; 987 size_t rlen = 0; 988 int r; 989 990 while (sshbuf_len(sect) > 0) { 991 if ((r = sshbuf_get_string(sect, &rdata, &rlen)) != 0) 992 return r; 993 if (expected_len != 0 && rlen != expected_len) { 994 error_f("bad length"); 995 free(rdata); 996 return SSH_ERR_INVALID_FORMAT; 997 } 998 if ((r = revoke_blob(target_tree, rdata, rlen)) != 0) { 999 free(rdata); 1000 return r; 1001 } 1002 } 1003 return 0; 1004 } 1005 1006 static int 1007 extension_section(struct sshbuf *sect, struct ssh_krl *krl) 1008 { 1009 int r = SSH_ERR_INTERNAL_ERROR; 1010 u_char critical = 1; 1011 struct sshbuf *value = NULL; 1012 char *name = NULL; 1013 1014 if ((r = sshbuf_get_cstring(sect, &name, NULL)) != 0 || 1015 (r = sshbuf_get_u8(sect, &critical)) != 0 || 1016 (r = sshbuf_froms(sect, &value)) != 0) { 1017 debug_fr(r, "parse"); 1018 error("KRL has invalid extension section"); 1019 r = SSH_ERR_INVALID_FORMAT; 1020 goto out; 1021 } 1022 if (sshbuf_len(sect) != 0) { 1023 error("KRL has invalid extension section: trailing data"); 1024 r = SSH_ERR_INVALID_FORMAT; 1025 goto out; 1026 } 1027 debug_f("extension %s critical %u len %zu", 1028 name, critical, sshbuf_len(value)); 1029 /* no extensions are currently supported */ 1030 if (critical) { 1031 error("KRL contains unsupported critical section \"%s\"", name); 1032 r = SSH_ERR_FEATURE_UNSUPPORTED; 1033 goto out; 1034 } 1035 /* success */ 1036 r = 0; 1037 out: 1038 free(name); 1039 sshbuf_free(value); 1040 return r; 1041 } 1042 1043 /* Attempt to parse a KRL */ 1044 int 1045 ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp) 1046 { 1047 struct sshbuf *copy = NULL, *sect = NULL; 1048 struct ssh_krl *krl = NULL; 1049 char timestamp[64]; 1050 int r = SSH_ERR_INTERNAL_ERROR; 1051 u_char type; 1052 u_int format_version; 1053 1054 *krlp = NULL; 1055 1056 /* KRL must begin with magic string */ 1057 if ((r = sshbuf_cmp(buf, 0, KRL_MAGIC, sizeof(KRL_MAGIC) - 1)) != 0) { 1058 debug2_f("bad KRL magic header"); 1059 return SSH_ERR_KRL_BAD_MAGIC; 1060 } 1061 1062 if ((krl = ssh_krl_init()) == NULL) { 1063 r = SSH_ERR_ALLOC_FAIL; 1064 error_f("alloc failed"); 1065 goto out; 1066 } 1067 /* Don't modify buffer */ 1068 if ((copy = sshbuf_fromb(buf)) == NULL) { 1069 r = SSH_ERR_ALLOC_FAIL; 1070 goto out; 1071 } 1072 if ((r = sshbuf_consume(copy, sizeof(KRL_MAGIC) - 1)) != 0 || 1073 (r = sshbuf_get_u32(copy, &format_version)) != 0) 1074 goto out; 1075 if (format_version != KRL_FORMAT_VERSION) { 1076 error_f("unsupported KRL format version %u", format_version); 1077 r = SSH_ERR_INVALID_FORMAT; 1078 goto out; 1079 } 1080 if ((r = sshbuf_get_u64(copy, &krl->krl_version)) != 0 || 1081 (r = sshbuf_get_u64(copy, &krl->generated_date)) != 0 || 1082 (r = sshbuf_get_u64(copy, &krl->flags)) != 0 || 1083 (r = sshbuf_skip_string(copy)) != 0 || 1084 (r = sshbuf_get_cstring(copy, &krl->comment, NULL)) != 0) { 1085 error_fr(r, "parse KRL header"); 1086 goto out; 1087 } 1088 format_timestamp(krl->generated_date, timestamp, sizeof(timestamp)); 1089 debug("KRL version %llu generated at %s%s%s", 1090 (long long unsigned)krl->krl_version, timestamp, 1091 *krl->comment ? ": " : "", krl->comment); 1092 1093 /* Parse and load the KRL sections. */ 1094 while (sshbuf_len(copy) > 0) { 1095 sshbuf_free(sect); 1096 sect = NULL; 1097 if ((r = sshbuf_get_u8(copy, &type)) != 0 || 1098 (r = sshbuf_froms(copy, §)) != 0) 1099 goto out; 1100 KRL_DBG(("section 0x%02x", type)); 1101 1102 switch (type) { 1103 case KRL_SECTION_CERTIFICATES: 1104 if ((r = parse_revoked_certs(sect, krl)) != 0) 1105 goto out; 1106 break; 1107 case KRL_SECTION_EXPLICIT_KEY: 1108 if ((r = blob_section(sect, 1109 &krl->revoked_keys, 0)) != 0) 1110 goto out; 1111 break; 1112 case KRL_SECTION_FINGERPRINT_SHA1: 1113 if ((r = blob_section(sect, 1114 &krl->revoked_sha1s, 20)) != 0) 1115 goto out; 1116 break; 1117 case KRL_SECTION_FINGERPRINT_SHA256: 1118 if ((r = blob_section(sect, 1119 &krl->revoked_sha256s, 32)) != 0) 1120 goto out; 1121 break; 1122 case KRL_SECTION_EXTENSION: 1123 if ((r = extension_section(sect, krl)) != 0) 1124 goto out; 1125 break; 1126 case KRL_SECTION_SIGNATURE: 1127 /* Handled above, but still need to stay in synch */ 1128 sshbuf_free(sect); 1129 sect = NULL; 1130 if ((r = sshbuf_skip_string(copy)) != 0) 1131 goto out; 1132 break; 1133 default: 1134 error("Unsupported KRL section %u", type); 1135 r = SSH_ERR_INVALID_FORMAT; 1136 goto out; 1137 } 1138 if (sect != NULL && sshbuf_len(sect) > 0) { 1139 error("KRL section contains unparsed data"); 1140 r = SSH_ERR_INVALID_FORMAT; 1141 goto out; 1142 } 1143 } 1144 1145 /* Success */ 1146 *krlp = krl; 1147 r = 0; 1148 out: 1149 if (r != 0) 1150 ssh_krl_free(krl); 1151 sshbuf_free(copy); 1152 sshbuf_free(sect); 1153 return r; 1154 } 1155 1156 /* Checks certificate serial number and key ID revocation */ 1157 static int 1158 is_cert_revoked(const struct sshkey *key, struct revoked_certs *rc) 1159 { 1160 struct revoked_serial rs, *ers; 1161 struct revoked_key_id rki, *erki; 1162 1163 /* Check revocation by cert key ID */ 1164 memset(&rki, 0, sizeof(rki)); 1165 rki.key_id = key->cert->key_id; 1166 erki = RB_FIND(revoked_key_id_tree, &rc->revoked_key_ids, &rki); 1167 if (erki != NULL) { 1168 KRL_DBG(("revoked by key ID")); 1169 return SSH_ERR_KEY_REVOKED; 1170 } 1171 1172 /* 1173 * Zero serials numbers are ignored (it's the default when the 1174 * CA doesn't specify one). 1175 */ 1176 if (key->cert->serial == 0) 1177 return 0; 1178 1179 memset(&rs, 0, sizeof(rs)); 1180 rs.lo = rs.hi = key->cert->serial; 1181 ers = RB_FIND(revoked_serial_tree, &rc->revoked_serials, &rs); 1182 if (ers != NULL) { 1183 KRL_DBG(("revoked serial %llu matched %llu:%llu", 1184 key->cert->serial, ers->lo, ers->hi)); 1185 return SSH_ERR_KEY_REVOKED; 1186 } 1187 return 0; 1188 } 1189 1190 /* Checks whether a given key/cert is revoked. Does not check its CA */ 1191 static int 1192 is_key_revoked(struct ssh_krl *krl, const struct sshkey *key) 1193 { 1194 struct revoked_blob rb, *erb; 1195 struct revoked_certs *rc; 1196 int r; 1197 1198 /* Check explicitly revoked hashes first */ 1199 memset(&rb, 0, sizeof(rb)); 1200 if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA1, 1201 &rb.blob, &rb.len)) != 0) 1202 return r; 1203 erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha1s, &rb); 1204 free(rb.blob); 1205 if (erb != NULL) { 1206 KRL_DBG(("revoked by key SHA1")); 1207 return SSH_ERR_KEY_REVOKED; 1208 } 1209 memset(&rb, 0, sizeof(rb)); 1210 if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA256, 1211 &rb.blob, &rb.len)) != 0) 1212 return r; 1213 erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha256s, &rb); 1214 free(rb.blob); 1215 if (erb != NULL) { 1216 KRL_DBG(("revoked by key SHA256")); 1217 return SSH_ERR_KEY_REVOKED; 1218 } 1219 1220 /* Next, explicit keys */ 1221 memset(&rb, 0, sizeof(rb)); 1222 if ((r = plain_key_blob(key, &rb.blob, &rb.len)) != 0) 1223 return r; 1224 erb = RB_FIND(revoked_blob_tree, &krl->revoked_keys, &rb); 1225 free(rb.blob); 1226 if (erb != NULL) { 1227 KRL_DBG(("revoked by explicit key")); 1228 return SSH_ERR_KEY_REVOKED; 1229 } 1230 1231 if (!sshkey_is_cert(key)) 1232 return 0; 1233 1234 /* Check cert revocation for the specified CA */ 1235 if ((r = revoked_certs_for_ca_key(krl, key->cert->signature_key, 1236 &rc, 0)) != 0) 1237 return r; 1238 if (rc != NULL) { 1239 if ((r = is_cert_revoked(key, rc)) != 0) 1240 return r; 1241 } 1242 /* Check cert revocation for the wildcard CA */ 1243 if ((r = revoked_certs_for_ca_key(krl, NULL, &rc, 0)) != 0) 1244 return r; 1245 if (rc != NULL) { 1246 if ((r = is_cert_revoked(key, rc)) != 0) 1247 return r; 1248 } 1249 1250 KRL_DBG(("%llu no match", key->cert->serial)); 1251 return 0; 1252 } 1253 1254 int 1255 ssh_krl_check_key(struct ssh_krl *krl, const struct sshkey *key) 1256 { 1257 int r; 1258 1259 KRL_DBG(("checking key")); 1260 if ((r = is_key_revoked(krl, key)) != 0) 1261 return r; 1262 if (sshkey_is_cert(key)) { 1263 debug2_f("checking CA key"); 1264 if ((r = is_key_revoked(krl, key->cert->signature_key)) != 0) 1265 return r; 1266 } 1267 KRL_DBG(("key okay")); 1268 return 0; 1269 } 1270 1271 int 1272 ssh_krl_file_contains_key(const char *path, const struct sshkey *key) 1273 { 1274 struct sshbuf *krlbuf = NULL; 1275 struct ssh_krl *krl = NULL; 1276 int oerrno = 0, r; 1277 1278 if (path == NULL) 1279 return 0; 1280 if ((r = sshbuf_load_file(path, &krlbuf)) != 0) { 1281 oerrno = errno; 1282 goto out; 1283 } 1284 if ((r = ssh_krl_from_blob(krlbuf, &krl)) != 0) 1285 goto out; 1286 debug2_f("checking KRL %s", path); 1287 r = ssh_krl_check_key(krl, key); 1288 out: 1289 sshbuf_free(krlbuf); 1290 ssh_krl_free(krl); 1291 if (r != 0) 1292 errno = oerrno; 1293 return r; 1294 } 1295 1296 int 1297 krl_dump(struct ssh_krl *krl, FILE *f) 1298 { 1299 struct sshkey *key = NULL; 1300 struct revoked_blob *rb; 1301 struct revoked_certs *rc; 1302 struct revoked_serial *rs; 1303 struct revoked_key_id *rki; 1304 int r, ret = 0; 1305 char *fp, timestamp[64]; 1306 1307 /* Try to print in a KRL spec-compatible format */ 1308 format_timestamp(krl->generated_date, timestamp, sizeof(timestamp)); 1309 fprintf(f, "# KRL version %llu\n", 1310 (unsigned long long)krl->krl_version); 1311 fprintf(f, "# Generated at %s\n", timestamp); 1312 if (krl->comment != NULL && *krl->comment != '\0') { 1313 r = INT_MAX; 1314 asmprintf(&fp, INT_MAX, &r, "%s", krl->comment); 1315 fprintf(f, "# Comment: %s\n", fp); 1316 free(fp); 1317 } 1318 fputc('\n', f); 1319 1320 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) { 1321 if ((r = sshkey_from_blob(rb->blob, rb->len, &key)) != 0) { 1322 ret = SSH_ERR_INVALID_FORMAT; 1323 error_r(r, "parse KRL key"); 1324 continue; 1325 } 1326 if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT, 1327 SSH_FP_DEFAULT)) == NULL) { 1328 ret = SSH_ERR_INVALID_FORMAT; 1329 error("sshkey_fingerprint failed"); 1330 continue; 1331 } 1332 fprintf(f, "hash: %s # %s\n", fp, sshkey_ssh_name(key)); 1333 free(fp); 1334 free(key); 1335 } 1336 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha256s) { 1337 fp = tohex(rb->blob, rb->len); 1338 fprintf(f, "hash: SHA256:%s\n", fp); 1339 free(fp); 1340 } 1341 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) { 1342 /* 1343 * There is not KRL spec keyword for raw SHA1 hashes, so 1344 * print them as comments. 1345 */ 1346 fp = tohex(rb->blob, rb->len); 1347 fprintf(f, "# hash SHA1:%s\n", fp); 1348 free(fp); 1349 } 1350 1351 TAILQ_FOREACH(rc, &krl->revoked_certs, entry) { 1352 fputc('\n', f); 1353 if (rc->ca_key == NULL) 1354 fprintf(f, "# Wildcard CA\n"); 1355 else { 1356 if ((fp = sshkey_fingerprint(rc->ca_key, 1357 SSH_FP_HASH_DEFAULT, SSH_FP_DEFAULT)) == NULL) { 1358 ret = SSH_ERR_INVALID_FORMAT; 1359 error("sshkey_fingerprint failed"); 1360 continue; 1361 } 1362 fprintf(f, "# CA key %s %s\n", 1363 sshkey_ssh_name(rc->ca_key), fp); 1364 free(fp); 1365 } 1366 RB_FOREACH(rs, revoked_serial_tree, &rc->revoked_serials) { 1367 if (rs->lo == rs->hi) { 1368 fprintf(f, "serial: %llu\n", 1369 (unsigned long long)rs->lo); 1370 } else { 1371 fprintf(f, "serial: %llu-%llu\n", 1372 (unsigned long long)rs->lo, 1373 (unsigned long long)rs->hi); 1374 } 1375 } 1376 RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) { 1377 /* 1378 * We don't want key IDs with embedded newlines to 1379 * mess up the display. 1380 */ 1381 r = INT_MAX; 1382 asmprintf(&fp, INT_MAX, &r, "%s", rki->key_id); 1383 fprintf(f, "id: %s\n", fp); 1384 free(fp); 1385 } 1386 } 1387 return ret; 1388 } 1389