1/* $OpenBSD: krl.c,v 1.59 2023/07/17 05:22:30 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 */ 57struct revoked_serial { 58 u_int64_t lo, hi; 59 RB_ENTRY(revoked_serial) tree_entry; 60}; 61static int serial_cmp(struct revoked_serial *a, struct revoked_serial *b); 62RB_HEAD(revoked_serial_tree, revoked_serial); 63RB_GENERATE_STATIC(revoked_serial_tree, revoked_serial, tree_entry, serial_cmp) 64 65/* Tree of key IDs */ 66struct revoked_key_id { 67 char *key_id; 68 RB_ENTRY(revoked_key_id) tree_entry; 69}; 70static int key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b); 71RB_HEAD(revoked_key_id_tree, revoked_key_id); 72RB_GENERATE_STATIC(revoked_key_id_tree, revoked_key_id, tree_entry, key_id_cmp) 73 74/* Tree of blobs (used for keys and fingerprints) */ 75struct revoked_blob { 76 u_char *blob; 77 size_t len; 78 RB_ENTRY(revoked_blob) tree_entry; 79}; 80static int blob_cmp(struct revoked_blob *a, struct revoked_blob *b); 81RB_HEAD(revoked_blob_tree, revoked_blob); 82RB_GENERATE_STATIC(revoked_blob_tree, revoked_blob, tree_entry, blob_cmp) 83 84/* Tracks revoked certs for a single CA */ 85struct 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}; 91TAILQ_HEAD(revoked_certs_list, revoked_certs); 92 93struct 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 */ 105static int 106serial_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 113static int 114key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b) 115{ 116 return strcmp(a->key_id, b->key_id); 117} 118 119static int 120blob_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 132struct ssh_krl * 133ssh_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 146static void 147revoked_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 164void 165ssh_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 196void 197ssh_krl_set_version(struct ssh_krl *krl, u_int64_t version) 198{ 199 krl->krl_version = version; 200} 201 202int 203ssh_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 */ 215static int 216revoked_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 249static int 250insert_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 319int 320ssh_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 326int 327ssh_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 340int 341ssh_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 */ 366static int 367plain_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 */ 386static int 387revoke_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 403int 404ssh_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 416static int 417revoke_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 433int 434ssh_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 442int 443ssh_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 451int 452ssh_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 */ 476static int 477choose_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 552static int 553put_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 */ 572static int 573revoked_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 error_f("insane bitmap gap"); 678 goto out; 679 } 680 for (i = 0; i < contig; i++) { 681 if (bitmap_set_bit(bitmap, 682 rs->lo + i - bitmap_start) != 0) { 683 r = SSH_ERR_ALLOC_FAIL; 684 goto out; 685 } 686 } 687 break; 688 } 689 last = rs->hi; 690 } 691 /* Flush the remaining section, if any */ 692 if (state != 0) { 693 KRL_DBG(("serial final flush for state 0x%02x", state)); 694 switch (state) { 695 case KRL_SECTION_CERT_SERIAL_LIST: 696 case KRL_SECTION_CERT_SERIAL_RANGE: 697 break; 698 case KRL_SECTION_CERT_SERIAL_BITMAP: 699 if ((r = put_bitmap(sect, bitmap)) != 0) 700 goto out; 701 bitmap_free(bitmap); 702 bitmap = NULL; 703 break; 704 } 705 if ((r = sshbuf_put_u8(buf, state)) != 0 || 706 (r = sshbuf_put_stringb(buf, sect)) != 0) 707 goto out; 708 } 709 KRL_DBG(("serial done ")); 710 711 /* Now output a section for any revocations by key ID */ 712 sshbuf_reset(sect); 713 RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) { 714 KRL_DBG(("key ID %s", rki->key_id)); 715 if ((r = sshbuf_put_cstring(sect, rki->key_id)) != 0) 716 goto out; 717 } 718 if (sshbuf_len(sect) != 0) { 719 if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERT_KEY_ID)) != 0 || 720 (r = sshbuf_put_stringb(buf, sect)) != 0) 721 goto out; 722 } 723 r = 0; 724 out: 725 bitmap_free(bitmap); 726 sshbuf_free(sect); 727 return r; 728} 729 730int 731ssh_krl_to_blob(struct ssh_krl *krl, struct sshbuf *buf) 732{ 733 int r = SSH_ERR_INTERNAL_ERROR; 734 struct revoked_certs *rc; 735 struct revoked_blob *rb; 736 struct sshbuf *sect; 737 u_char *sblob = NULL; 738 739 if (krl->generated_date == 0) 740 krl->generated_date = time(NULL); 741 742 if ((sect = sshbuf_new()) == NULL) 743 return SSH_ERR_ALLOC_FAIL; 744 745 /* Store the header */ 746 if ((r = sshbuf_put(buf, KRL_MAGIC, sizeof(KRL_MAGIC) - 1)) != 0 || 747 (r = sshbuf_put_u32(buf, KRL_FORMAT_VERSION)) != 0 || 748 (r = sshbuf_put_u64(buf, krl->krl_version)) != 0 || 749 (r = sshbuf_put_u64(buf, krl->generated_date)) != 0 || 750 (r = sshbuf_put_u64(buf, krl->flags)) != 0 || 751 (r = sshbuf_put_string(buf, NULL, 0)) != 0 || 752 (r = sshbuf_put_cstring(buf, krl->comment)) != 0) 753 goto out; 754 755 /* Store sections for revoked certificates */ 756 TAILQ_FOREACH(rc, &krl->revoked_certs, entry) { 757 sshbuf_reset(sect); 758 if ((r = revoked_certs_generate(rc, sect)) != 0) 759 goto out; 760 if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERTIFICATES)) != 0 || 761 (r = sshbuf_put_stringb(buf, sect)) != 0) 762 goto out; 763 } 764 765 /* Finally, output sections for revocations by public key/hash */ 766 sshbuf_reset(sect); 767 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) { 768 KRL_DBG(("key len %zu ", rb->len)); 769 if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0) 770 goto out; 771 } 772 if (sshbuf_len(sect) != 0) { 773 if ((r = sshbuf_put_u8(buf, KRL_SECTION_EXPLICIT_KEY)) != 0 || 774 (r = sshbuf_put_stringb(buf, sect)) != 0) 775 goto out; 776 } 777 sshbuf_reset(sect); 778 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) { 779 KRL_DBG(("hash len %zu ", rb->len)); 780 if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0) 781 goto out; 782 } 783 if (sshbuf_len(sect) != 0) { 784 if ((r = sshbuf_put_u8(buf, 785 KRL_SECTION_FINGERPRINT_SHA1)) != 0 || 786 (r = sshbuf_put_stringb(buf, sect)) != 0) 787 goto out; 788 } 789 sshbuf_reset(sect); 790 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha256s) { 791 KRL_DBG(("hash len %zu ", rb->len)); 792 if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0) 793 goto out; 794 } 795 if (sshbuf_len(sect) != 0) { 796 if ((r = sshbuf_put_u8(buf, 797 KRL_SECTION_FINGERPRINT_SHA256)) != 0 || 798 (r = sshbuf_put_stringb(buf, sect)) != 0) 799 goto out; 800 } 801 /* success */ 802 r = 0; 803 out: 804 free(sblob); 805 sshbuf_free(sect); 806 return r; 807} 808 809static void 810format_timestamp(u_int64_t timestamp, char *ts, size_t nts) 811{ 812 time_t t; 813 struct tm *tm; 814 815 t = timestamp; 816 tm = localtime(&t); 817 if (tm == NULL) 818 strlcpy(ts, "<INVALID>", nts); 819 else { 820 *ts = '\0'; 821 strftime(ts, nts, "%Y%m%dT%H%M%S", tm); 822 } 823} 824 825static int 826cert_extension_subsection(struct sshbuf *subsect, struct ssh_krl *krl) 827{ 828 int r = SSH_ERR_INTERNAL_ERROR; 829 u_char critical = 1; 830 struct sshbuf *value = NULL; 831 char *name = NULL; 832 833 if ((r = sshbuf_get_cstring(subsect, &name, NULL)) != 0 || 834 (r = sshbuf_get_u8(subsect, &critical)) != 0 || 835 (r = sshbuf_froms(subsect, &value)) != 0) { 836 debug_fr(r, "parse"); 837 error("KRL has invalid certificate extension subsection"); 838 r = SSH_ERR_INVALID_FORMAT; 839 goto out; 840 } 841 if (sshbuf_len(subsect) != 0) { 842 error("KRL has invalid certificate extension subsection: " 843 "trailing data"); 844 r = SSH_ERR_INVALID_FORMAT; 845 goto out; 846 } 847 debug_f("cert extension %s critical %u len %zu", 848 name, critical, sshbuf_len(value)); 849 /* no extensions are currently supported */ 850 if (critical) { 851 error("KRL contains unsupported critical certificate " 852 "subsection \"%s\"", name); 853 r = SSH_ERR_FEATURE_UNSUPPORTED; 854 goto out; 855 } 856 /* success */ 857 r = 0; 858 out: 859 free(name); 860 sshbuf_free(value); 861 return r; 862} 863 864static int 865parse_revoked_certs(struct sshbuf *buf, struct ssh_krl *krl) 866{ 867 int r = SSH_ERR_INTERNAL_ERROR; 868 u_char type; 869 const u_char *blob; 870 size_t blen, nbits; 871 struct sshbuf *subsect = NULL; 872 u_int64_t serial, serial_lo, serial_hi; 873 struct bitmap *bitmap = NULL; 874 char *key_id = NULL; 875 struct sshkey *ca_key = NULL; 876 877 if ((subsect = sshbuf_new()) == NULL) 878 return SSH_ERR_ALLOC_FAIL; 879 880 /* Header: key, reserved */ 881 if ((r = sshbuf_get_string_direct(buf, &blob, &blen)) != 0 || 882 (r = sshbuf_skip_string(buf)) != 0) 883 goto out; 884 if (blen != 0 && (r = sshkey_from_blob(blob, blen, &ca_key)) != 0) 885 goto out; 886 887 while (sshbuf_len(buf) > 0) { 888 sshbuf_free(subsect); 889 subsect = NULL; 890 if ((r = sshbuf_get_u8(buf, &type)) != 0 || 891 (r = sshbuf_froms(buf, &subsect)) != 0) 892 goto out; 893 KRL_DBG(("subsection type 0x%02x", type)); 894 /* sshbuf_dump(subsect, stderr); */ 895 896 switch (type) { 897 case KRL_SECTION_CERT_SERIAL_LIST: 898 while (sshbuf_len(subsect) > 0) { 899 if ((r = sshbuf_get_u64(subsect, &serial)) != 0) 900 goto out; 901 if ((r = ssh_krl_revoke_cert_by_serial(krl, 902 ca_key, serial)) != 0) 903 goto out; 904 } 905 break; 906 case KRL_SECTION_CERT_SERIAL_RANGE: 907 if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 || 908 (r = sshbuf_get_u64(subsect, &serial_hi)) != 0) 909 goto out; 910 if ((r = ssh_krl_revoke_cert_by_serial_range(krl, 911 ca_key, serial_lo, serial_hi)) != 0) 912 goto out; 913 break; 914 case KRL_SECTION_CERT_SERIAL_BITMAP: 915 if ((bitmap = bitmap_new()) == NULL) { 916 r = SSH_ERR_ALLOC_FAIL; 917 goto out; 918 } 919 if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 || 920 (r = sshbuf_get_bignum2_bytes_direct(subsect, 921 &blob, &blen)) != 0) 922 goto out; 923 if (bitmap_from_string(bitmap, blob, blen) != 0) { 924 r = SSH_ERR_INVALID_FORMAT; 925 goto out; 926 } 927 nbits = bitmap_nbits(bitmap); 928 for (serial = 0; serial < (u_int64_t)nbits; serial++) { 929 if (serial > 0 && serial_lo + serial == 0) { 930 error_f("bitmap wraps u64"); 931 r = SSH_ERR_INVALID_FORMAT; 932 goto out; 933 } 934 if (!bitmap_test_bit(bitmap, serial)) 935 continue; 936 if ((r = ssh_krl_revoke_cert_by_serial(krl, 937 ca_key, serial_lo + serial)) != 0) 938 goto out; 939 } 940 bitmap_free(bitmap); 941 bitmap = NULL; 942 break; 943 case KRL_SECTION_CERT_KEY_ID: 944 while (sshbuf_len(subsect) > 0) { 945 if ((r = sshbuf_get_cstring(subsect, 946 &key_id, NULL)) != 0) 947 goto out; 948 if ((r = ssh_krl_revoke_cert_by_key_id(krl, 949 ca_key, key_id)) != 0) 950 goto out; 951 free(key_id); 952 key_id = NULL; 953 } 954 break; 955 case KRL_SECTION_CERT_EXTENSION: 956 if ((r = cert_extension_subsection(subsect, krl)) != 0) 957 goto out; 958 break; 959 default: 960 error("Unsupported KRL certificate section %u", type); 961 r = SSH_ERR_INVALID_FORMAT; 962 goto out; 963 } 964 if (sshbuf_len(subsect) > 0) { 965 error("KRL certificate section contains unparsed data"); 966 r = SSH_ERR_INVALID_FORMAT; 967 goto out; 968 } 969 } 970 971 r = 0; 972 out: 973 if (bitmap != NULL) 974 bitmap_free(bitmap); 975 free(key_id); 976 sshkey_free(ca_key); 977 sshbuf_free(subsect); 978 return r; 979} 980 981static int 982blob_section(struct sshbuf *sect, struct revoked_blob_tree *target_tree, 983 size_t expected_len) 984{ 985 u_char *rdata = NULL; 986 size_t rlen = 0; 987 int r; 988 989 while (sshbuf_len(sect) > 0) { 990 if ((r = sshbuf_get_string(sect, &rdata, &rlen)) != 0) 991 return r; 992 if (expected_len != 0 && rlen != expected_len) { 993 error_f("bad length"); 994 free(rdata); 995 return SSH_ERR_INVALID_FORMAT; 996 } 997 if ((r = revoke_blob(target_tree, rdata, rlen)) != 0) { 998 free(rdata); 999 return r; 1000 } 1001 } 1002 return 0; 1003} 1004 1005static int 1006extension_section(struct sshbuf *sect, struct ssh_krl *krl) 1007{ 1008 int r = SSH_ERR_INTERNAL_ERROR; 1009 u_char critical = 1; 1010 struct sshbuf *value = NULL; 1011 char *name = NULL; 1012 1013 if ((r = sshbuf_get_cstring(sect, &name, NULL)) != 0 || 1014 (r = sshbuf_get_u8(sect, &critical)) != 0 || 1015 (r = sshbuf_froms(sect, &value)) != 0) { 1016 debug_fr(r, "parse"); 1017 error("KRL has invalid extension section"); 1018 r = SSH_ERR_INVALID_FORMAT; 1019 goto out; 1020 } 1021 if (sshbuf_len(sect) != 0) { 1022 error("KRL has invalid extension section: trailing data"); 1023 r = SSH_ERR_INVALID_FORMAT; 1024 goto out; 1025 } 1026 debug_f("extension %s critical %u len %zu", 1027 name, critical, sshbuf_len(value)); 1028 /* no extensions are currently supported */ 1029 if (critical) { 1030 error("KRL contains unsupported critical section \"%s\"", name); 1031 r = SSH_ERR_FEATURE_UNSUPPORTED; 1032 goto out; 1033 } 1034 /* success */ 1035 r = 0; 1036 out: 1037 free(name); 1038 sshbuf_free(value); 1039 return r; 1040} 1041 1042/* Attempt to parse a KRL */ 1043int 1044ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp) 1045{ 1046 struct sshbuf *copy = NULL, *sect = NULL; 1047 struct ssh_krl *krl = NULL; 1048 char timestamp[64]; 1049 int r = SSH_ERR_INTERNAL_ERROR; 1050 u_char type; 1051 u_int format_version; 1052 1053 *krlp = NULL; 1054 1055 /* KRL must begin with magic string */ 1056 if ((r = sshbuf_cmp(buf, 0, KRL_MAGIC, sizeof(KRL_MAGIC) - 1)) != 0) { 1057 debug2_f("bad KRL magic header"); 1058 return SSH_ERR_KRL_BAD_MAGIC; 1059 } 1060 1061 if ((krl = ssh_krl_init()) == NULL) { 1062 error_f("alloc failed"); 1063 goto out; 1064 } 1065 /* Don't modify buffer */ 1066 if ((copy = sshbuf_fromb(buf)) == NULL) { 1067 r = SSH_ERR_ALLOC_FAIL; 1068 goto out; 1069 } 1070 if ((r = sshbuf_consume(copy, sizeof(KRL_MAGIC) - 1)) != 0 || 1071 (r = sshbuf_get_u32(copy, &format_version)) != 0) 1072 goto out; 1073 if (format_version != KRL_FORMAT_VERSION) { 1074 error_f("unsupported KRL format version %u", format_version); 1075 r = SSH_ERR_INVALID_FORMAT; 1076 goto out; 1077 } 1078 if ((r = sshbuf_get_u64(copy, &krl->krl_version)) != 0 || 1079 (r = sshbuf_get_u64(copy, &krl->generated_date)) != 0 || 1080 (r = sshbuf_get_u64(copy, &krl->flags)) != 0 || 1081 (r = sshbuf_skip_string(copy)) != 0 || 1082 (r = sshbuf_get_cstring(copy, &krl->comment, NULL)) != 0) { 1083 error_fr(r, "parse KRL header"); 1084 goto out; 1085 } 1086 format_timestamp(krl->generated_date, timestamp, sizeof(timestamp)); 1087 debug("KRL version %llu generated at %s%s%s", 1088 (long long unsigned)krl->krl_version, timestamp, 1089 *krl->comment ? ": " : "", krl->comment); 1090 1091 /* Parse and load the KRL sections. */ 1092 while (sshbuf_len(copy) > 0) { 1093 sshbuf_free(sect); 1094 sect = NULL; 1095 if ((r = sshbuf_get_u8(copy, &type)) != 0 || 1096 (r = sshbuf_froms(copy, §)) != 0) 1097 goto out; 1098 KRL_DBG(("section 0x%02x", type)); 1099 1100 switch (type) { 1101 case KRL_SECTION_CERTIFICATES: 1102 if ((r = parse_revoked_certs(sect, krl)) != 0) 1103 goto out; 1104 break; 1105 case KRL_SECTION_EXPLICIT_KEY: 1106 if ((r = blob_section(sect, 1107 &krl->revoked_keys, 0)) != 0) 1108 goto out; 1109 break; 1110 case KRL_SECTION_FINGERPRINT_SHA1: 1111 if ((r = blob_section(sect, 1112 &krl->revoked_sha1s, 20)) != 0) 1113 goto out; 1114 break; 1115 case KRL_SECTION_FINGERPRINT_SHA256: 1116 if ((r = blob_section(sect, 1117 &krl->revoked_sha256s, 32)) != 0) 1118 goto out; 1119 break; 1120 case KRL_SECTION_EXTENSION: 1121 if ((r = extension_section(sect, krl)) != 0) 1122 goto out; 1123 break; 1124 case KRL_SECTION_SIGNATURE: 1125 /* Handled above, but still need to stay in synch */ 1126 sshbuf_free(sect); 1127 sect = NULL; 1128 if ((r = sshbuf_skip_string(copy)) != 0) 1129 goto out; 1130 break; 1131 default: 1132 error("Unsupported KRL section %u", type); 1133 r = SSH_ERR_INVALID_FORMAT; 1134 goto out; 1135 } 1136 if (sect != NULL && sshbuf_len(sect) > 0) { 1137 error("KRL section contains unparsed data"); 1138 r = SSH_ERR_INVALID_FORMAT; 1139 goto out; 1140 } 1141 } 1142 1143 /* Success */ 1144 *krlp = krl; 1145 r = 0; 1146 out: 1147 if (r != 0) 1148 ssh_krl_free(krl); 1149 sshbuf_free(copy); 1150 sshbuf_free(sect); 1151 return r; 1152} 1153 1154/* Checks certificate serial number and key ID revocation */ 1155static int 1156is_cert_revoked(const struct sshkey *key, struct revoked_certs *rc) 1157{ 1158 struct revoked_serial rs, *ers; 1159 struct revoked_key_id rki, *erki; 1160 1161 /* Check revocation by cert key ID */ 1162 memset(&rki, 0, sizeof(rki)); 1163 rki.key_id = key->cert->key_id; 1164 erki = RB_FIND(revoked_key_id_tree, &rc->revoked_key_ids, &rki); 1165 if (erki != NULL) { 1166 KRL_DBG(("revoked by key ID")); 1167 return SSH_ERR_KEY_REVOKED; 1168 } 1169 1170 /* 1171 * Zero serials numbers are ignored (it's the default when the 1172 * CA doesn't specify one). 1173 */ 1174 if (key->cert->serial == 0) 1175 return 0; 1176 1177 memset(&rs, 0, sizeof(rs)); 1178 rs.lo = rs.hi = key->cert->serial; 1179 ers = RB_FIND(revoked_serial_tree, &rc->revoked_serials, &rs); 1180 if (ers != NULL) { 1181 KRL_DBG(("revoked serial %llu matched %llu:%llu", 1182 key->cert->serial, ers->lo, ers->hi)); 1183 return SSH_ERR_KEY_REVOKED; 1184 } 1185 return 0; 1186} 1187 1188/* Checks whether a given key/cert is revoked. Does not check its CA */ 1189static int 1190is_key_revoked(struct ssh_krl *krl, const struct sshkey *key) 1191{ 1192 struct revoked_blob rb, *erb; 1193 struct revoked_certs *rc; 1194 int r; 1195 1196 /* Check explicitly revoked hashes first */ 1197 memset(&rb, 0, sizeof(rb)); 1198 if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA1, 1199 &rb.blob, &rb.len)) != 0) 1200 return r; 1201 erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha1s, &rb); 1202 free(rb.blob); 1203 if (erb != NULL) { 1204 KRL_DBG(("revoked by key SHA1")); 1205 return SSH_ERR_KEY_REVOKED; 1206 } 1207 memset(&rb, 0, sizeof(rb)); 1208 if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA256, 1209 &rb.blob, &rb.len)) != 0) 1210 return r; 1211 erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha256s, &rb); 1212 free(rb.blob); 1213 if (erb != NULL) { 1214 KRL_DBG(("revoked by key SHA256")); 1215 return SSH_ERR_KEY_REVOKED; 1216 } 1217 1218 /* Next, explicit keys */ 1219 memset(&rb, 0, sizeof(rb)); 1220 if ((r = plain_key_blob(key, &rb.blob, &rb.len)) != 0) 1221 return r; 1222 erb = RB_FIND(revoked_blob_tree, &krl->revoked_keys, &rb); 1223 free(rb.blob); 1224 if (erb != NULL) { 1225 KRL_DBG(("revoked by explicit key")); 1226 return SSH_ERR_KEY_REVOKED; 1227 } 1228 1229 if (!sshkey_is_cert(key)) 1230 return 0; 1231 1232 /* Check cert revocation for the specified CA */ 1233 if ((r = revoked_certs_for_ca_key(krl, key->cert->signature_key, 1234 &rc, 0)) != 0) 1235 return r; 1236 if (rc != NULL) { 1237 if ((r = is_cert_revoked(key, rc)) != 0) 1238 return r; 1239 } 1240 /* Check cert revocation for the wildcard CA */ 1241 if ((r = revoked_certs_for_ca_key(krl, NULL, &rc, 0)) != 0) 1242 return r; 1243 if (rc != NULL) { 1244 if ((r = is_cert_revoked(key, rc)) != 0) 1245 return r; 1246 } 1247 1248 KRL_DBG(("%llu no match", key->cert->serial)); 1249 return 0; 1250} 1251 1252int 1253ssh_krl_check_key(struct ssh_krl *krl, const struct sshkey *key) 1254{ 1255 int r; 1256 1257 KRL_DBG(("checking key")); 1258 if ((r = is_key_revoked(krl, key)) != 0) 1259 return r; 1260 if (sshkey_is_cert(key)) { 1261 debug2_f("checking CA key"); 1262 if ((r = is_key_revoked(krl, key->cert->signature_key)) != 0) 1263 return r; 1264 } 1265 KRL_DBG(("key okay")); 1266 return 0; 1267} 1268 1269int 1270ssh_krl_file_contains_key(const char *path, const struct sshkey *key) 1271{ 1272 struct sshbuf *krlbuf = NULL; 1273 struct ssh_krl *krl = NULL; 1274 int oerrno = 0, r; 1275 1276 if (path == NULL) 1277 return 0; 1278 if ((r = sshbuf_load_file(path, &krlbuf)) != 0) { 1279 oerrno = errno; 1280 goto out; 1281 } 1282 if ((r = ssh_krl_from_blob(krlbuf, &krl)) != 0) 1283 goto out; 1284 debug2_f("checking KRL %s", path); 1285 r = ssh_krl_check_key(krl, key); 1286 out: 1287 sshbuf_free(krlbuf); 1288 ssh_krl_free(krl); 1289 if (r != 0) 1290 errno = oerrno; 1291 return r; 1292} 1293 1294int 1295krl_dump(struct ssh_krl *krl, FILE *f) 1296{ 1297 struct sshkey *key = NULL; 1298 struct revoked_blob *rb; 1299 struct revoked_certs *rc; 1300 struct revoked_serial *rs; 1301 struct revoked_key_id *rki; 1302 int r, ret = 0; 1303 char *fp, timestamp[64]; 1304 1305 /* Try to print in a KRL spec-compatible format */ 1306 format_timestamp(krl->generated_date, timestamp, sizeof(timestamp)); 1307 fprintf(f, "# KRL version %llu\n", 1308 (unsigned long long)krl->krl_version); 1309 fprintf(f, "# Generated at %s\n", timestamp); 1310 if (krl->comment != NULL && *krl->comment != '\0') { 1311 r = INT_MAX; 1312 asmprintf(&fp, INT_MAX, &r, "%s", krl->comment); 1313 fprintf(f, "# Comment: %s\n", fp); 1314 free(fp); 1315 } 1316 fputc('\n', f); 1317 1318 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) { 1319 if ((r = sshkey_from_blob(rb->blob, rb->len, &key)) != 0) { 1320 ret = SSH_ERR_INVALID_FORMAT; 1321 error_r(r, "parse KRL key"); 1322 continue; 1323 } 1324 if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT, 1325 SSH_FP_DEFAULT)) == NULL) { 1326 ret = SSH_ERR_INVALID_FORMAT; 1327 error("sshkey_fingerprint failed"); 1328 continue; 1329 } 1330 fprintf(f, "hash: %s # %s\n", fp, sshkey_ssh_name(key)); 1331 free(fp); 1332 free(key); 1333 } 1334 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha256s) { 1335 fp = tohex(rb->blob, rb->len); 1336 fprintf(f, "hash: SHA256:%s\n", fp); 1337 free(fp); 1338 } 1339 RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) { 1340 /* 1341 * There is not KRL spec keyword for raw SHA1 hashes, so 1342 * print them as comments. 1343 */ 1344 fp = tohex(rb->blob, rb->len); 1345 fprintf(f, "# hash SHA1:%s\n", fp); 1346 free(fp); 1347 } 1348 1349 TAILQ_FOREACH(rc, &krl->revoked_certs, entry) { 1350 fputc('\n', f); 1351 if (rc->ca_key == NULL) 1352 fprintf(f, "# Wildcard CA\n"); 1353 else { 1354 if ((fp = sshkey_fingerprint(rc->ca_key, 1355 SSH_FP_HASH_DEFAULT, SSH_FP_DEFAULT)) == NULL) { 1356 ret = SSH_ERR_INVALID_FORMAT; 1357 error("sshkey_fingerprint failed"); 1358 continue; 1359 } 1360 fprintf(f, "# CA key %s %s\n", 1361 sshkey_ssh_name(rc->ca_key), fp); 1362 free(fp); 1363 } 1364 RB_FOREACH(rs, revoked_serial_tree, &rc->revoked_serials) { 1365 if (rs->lo == rs->hi) { 1366 fprintf(f, "serial: %llu\n", 1367 (unsigned long long)rs->lo); 1368 } else { 1369 fprintf(f, "serial: %llu-%llu\n", 1370 (unsigned long long)rs->lo, 1371 (unsigned long long)rs->hi); 1372 } 1373 } 1374 RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) { 1375 /* 1376 * We don't want key IDs with embedded newlines to 1377 * mess up the display. 1378 */ 1379 r = INT_MAX; 1380 asmprintf(&fp, INT_MAX, &r, "%s", rki->key_id); 1381 fprintf(f, "id: %s\n", fp); 1382 free(fp); 1383 } 1384 } 1385 return ret; 1386} 1387