Annotation of src/usr.bin/ssh/krl.c, Revision 1.25
1.1 djm 1: /*
2: * Copyright (c) 2012 Damien Miller <djm@mindrot.org>
3: *
4: * Permission to use, copy, modify, and distribute this software for any
5: * purpose with or without fee is hereby granted, provided that the above
6: * copyright notice and this permission notice appear in all copies.
7: *
8: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15: */
16:
1.25 ! djm 17: /* $OpenBSD: krl.c,v 1.24 2015/01/12 19:22:46 markus Exp $ */
1.2 djm 18:
1.1 djm 19: #include <sys/types.h>
20: #include <sys/param.h>
21: #include <sys/tree.h>
22: #include <sys/queue.h>
23:
24: #include <errno.h>
25: #include <fcntl.h>
26: #include <limits.h>
27: #include <string.h>
28: #include <time.h>
29: #include <unistd.h>
30:
1.20 djm 31: #include "sshbuf.h"
1.25 ! djm 32: #include "ssherr.h"
1.20 djm 33: #include "sshkey.h"
1.1 djm 34: #include "authfile.h"
35: #include "misc.h"
36: #include "log.h"
1.21 djm 37: #include "digest.h"
1.1 djm 38:
39: #include "krl.h"
40:
41: /* #define DEBUG_KRL */
42: #ifdef DEBUG_KRL
43: # define KRL_DBG(x) debug3 x
44: #else
45: # define KRL_DBG(x)
46: #endif
47:
48: /*
49: * Trees of revoked serial numbers, key IDs and keys. This allows
50: * quick searching, querying and producing lists in canonical order.
51: */
52:
53: /* Tree of serial numbers. XXX make smarter: really need a real sparse bitmap */
54: struct revoked_serial {
55: u_int64_t lo, hi;
56: RB_ENTRY(revoked_serial) tree_entry;
57: };
58: static int serial_cmp(struct revoked_serial *a, struct revoked_serial *b);
59: RB_HEAD(revoked_serial_tree, revoked_serial);
60: RB_GENERATE_STATIC(revoked_serial_tree, revoked_serial, tree_entry, serial_cmp);
61:
62: /* Tree of key IDs */
63: struct revoked_key_id {
64: char *key_id;
65: RB_ENTRY(revoked_key_id) tree_entry;
66: };
67: static int key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b);
68: RB_HEAD(revoked_key_id_tree, revoked_key_id);
69: RB_GENERATE_STATIC(revoked_key_id_tree, revoked_key_id, tree_entry, key_id_cmp);
70:
71: /* Tree of blobs (used for keys and fingerprints) */
72: struct revoked_blob {
73: u_char *blob;
1.20 djm 74: size_t len;
1.1 djm 75: RB_ENTRY(revoked_blob) tree_entry;
76: };
77: static int blob_cmp(struct revoked_blob *a, struct revoked_blob *b);
78: RB_HEAD(revoked_blob_tree, revoked_blob);
79: RB_GENERATE_STATIC(revoked_blob_tree, revoked_blob, tree_entry, blob_cmp);
80:
81: /* Tracks revoked certs for a single CA */
82: struct revoked_certs {
1.20 djm 83: struct sshkey *ca_key;
1.1 djm 84: struct revoked_serial_tree revoked_serials;
85: struct revoked_key_id_tree revoked_key_ids;
86: TAILQ_ENTRY(revoked_certs) entry;
87: };
88: TAILQ_HEAD(revoked_certs_list, revoked_certs);
89:
90: struct ssh_krl {
91: u_int64_t krl_version;
92: u_int64_t generated_date;
93: u_int64_t flags;
94: char *comment;
95: struct revoked_blob_tree revoked_keys;
96: struct revoked_blob_tree revoked_sha1s;
97: struct revoked_certs_list revoked_certs;
98: };
99:
100: /* Return equal if a and b overlap */
101: static int
102: serial_cmp(struct revoked_serial *a, struct revoked_serial *b)
103: {
104: if (a->hi >= b->lo && a->lo <= b->hi)
105: return 0;
106: return a->lo < b->lo ? -1 : 1;
107: }
108:
109: static int
110: key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b)
111: {
112: return strcmp(a->key_id, b->key_id);
113: }
114:
115: static int
116: blob_cmp(struct revoked_blob *a, struct revoked_blob *b)
117: {
118: int r;
119:
120: if (a->len != b->len) {
121: if ((r = memcmp(a->blob, b->blob, MIN(a->len, b->len))) != 0)
122: return r;
123: return a->len > b->len ? 1 : -1;
124: } else
125: return memcmp(a->blob, b->blob, a->len);
126: }
127:
128: struct ssh_krl *
129: ssh_krl_init(void)
130: {
131: struct ssh_krl *krl;
132:
133: if ((krl = calloc(1, sizeof(*krl))) == NULL)
134: return NULL;
135: RB_INIT(&krl->revoked_keys);
136: RB_INIT(&krl->revoked_sha1s);
137: TAILQ_INIT(&krl->revoked_certs);
138: return krl;
139: }
140:
141: static void
142: revoked_certs_free(struct revoked_certs *rc)
143: {
144: struct revoked_serial *rs, *trs;
145: struct revoked_key_id *rki, *trki;
146:
147: RB_FOREACH_SAFE(rs, revoked_serial_tree, &rc->revoked_serials, trs) {
148: RB_REMOVE(revoked_serial_tree, &rc->revoked_serials, rs);
149: free(rs);
150: }
151: RB_FOREACH_SAFE(rki, revoked_key_id_tree, &rc->revoked_key_ids, trki) {
152: RB_REMOVE(revoked_key_id_tree, &rc->revoked_key_ids, rki);
153: free(rki->key_id);
154: free(rki);
155: }
156: if (rc->ca_key != NULL)
1.20 djm 157: sshkey_free(rc->ca_key);
1.1 djm 158: }
159:
160: void
161: ssh_krl_free(struct ssh_krl *krl)
162: {
163: struct revoked_blob *rb, *trb;
164: struct revoked_certs *rc, *trc;
165:
166: if (krl == NULL)
167: return;
168:
169: free(krl->comment);
170: RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_keys, trb) {
171: RB_REMOVE(revoked_blob_tree, &krl->revoked_keys, rb);
172: free(rb->blob);
173: free(rb);
174: }
175: RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_sha1s, trb) {
176: RB_REMOVE(revoked_blob_tree, &krl->revoked_sha1s, rb);
177: free(rb->blob);
178: free(rb);
179: }
180: TAILQ_FOREACH_SAFE(rc, &krl->revoked_certs, entry, trc) {
181: TAILQ_REMOVE(&krl->revoked_certs, rc, entry);
182: revoked_certs_free(rc);
183: }
184: }
185:
186: void
187: ssh_krl_set_version(struct ssh_krl *krl, u_int64_t version)
188: {
189: krl->krl_version = version;
190: }
191:
1.20 djm 192: int
1.1 djm 193: ssh_krl_set_comment(struct ssh_krl *krl, const char *comment)
194: {
195: free(krl->comment);
196: if ((krl->comment = strdup(comment)) == NULL)
1.20 djm 197: return SSH_ERR_ALLOC_FAIL;
198: return 0;
1.1 djm 199: }
200:
201: /*
202: * Find the revoked_certs struct for a CA key. If allow_create is set then
203: * create a new one in the tree if one did not exist already.
204: */
205: static int
1.20 djm 206: revoked_certs_for_ca_key(struct ssh_krl *krl, const struct sshkey *ca_key,
1.1 djm 207: struct revoked_certs **rcp, int allow_create)
208: {
209: struct revoked_certs *rc;
1.20 djm 210: int r;
1.1 djm 211:
212: *rcp = NULL;
213: TAILQ_FOREACH(rc, &krl->revoked_certs, entry) {
1.20 djm 214: if (sshkey_equal(rc->ca_key, ca_key)) {
1.1 djm 215: *rcp = rc;
216: return 0;
217: }
218: }
219: if (!allow_create)
220: return 0;
221: /* If this CA doesn't exist in the list then add it now */
222: if ((rc = calloc(1, sizeof(*rc))) == NULL)
1.20 djm 223: return SSH_ERR_ALLOC_FAIL;
224: if ((r = sshkey_from_private(ca_key, &rc->ca_key)) != 0) {
1.1 djm 225: free(rc);
1.20 djm 226: return r;
1.1 djm 227: }
228: RB_INIT(&rc->revoked_serials);
229: RB_INIT(&rc->revoked_key_ids);
230: TAILQ_INSERT_TAIL(&krl->revoked_certs, rc, entry);
1.25 ! djm 231: KRL_DBG(("%s: new CA %s", __func__, sshkey_type(ca_key)));
1.1 djm 232: *rcp = rc;
233: return 0;
234: }
235:
236: static int
237: insert_serial_range(struct revoked_serial_tree *rt, u_int64_t lo, u_int64_t hi)
238: {
239: struct revoked_serial rs, *ers, *crs, *irs;
240:
241: KRL_DBG(("%s: insert %llu:%llu", __func__, lo, hi));
1.14 tedu 242: memset(&rs, 0, sizeof(rs));
1.1 djm 243: rs.lo = lo;
244: rs.hi = hi;
245: ers = RB_NFIND(revoked_serial_tree, rt, &rs);
246: if (ers == NULL || serial_cmp(ers, &rs) != 0) {
247: /* No entry matches. Just insert */
248: if ((irs = malloc(sizeof(rs))) == NULL)
1.20 djm 249: return SSH_ERR_ALLOC_FAIL;
1.1 djm 250: memcpy(irs, &rs, sizeof(*irs));
251: ers = RB_INSERT(revoked_serial_tree, rt, irs);
252: if (ers != NULL) {
253: KRL_DBG(("%s: bad: ers != NULL", __func__));
254: /* Shouldn't happen */
1.4 markus 255: free(irs);
1.25 ! djm 256: return SSH_ERR_INTERNAL_ERROR;
1.1 djm 257: }
258: ers = irs;
259: } else {
260: KRL_DBG(("%s: overlap found %llu:%llu", __func__,
261: ers->lo, ers->hi));
262: /*
263: * The inserted entry overlaps an existing one. Grow the
264: * existing entry.
265: */
266: if (ers->lo > lo)
267: ers->lo = lo;
268: if (ers->hi < hi)
269: ers->hi = hi;
270: }
1.25 ! djm 271:
1.1 djm 272: /*
273: * The inserted or revised range might overlap or abut adjacent ones;
274: * coalesce as necessary.
275: */
276:
277: /* Check predecessors */
278: while ((crs = RB_PREV(revoked_serial_tree, rt, ers)) != NULL) {
279: KRL_DBG(("%s: pred %llu:%llu", __func__, crs->lo, crs->hi));
280: if (ers->lo != 0 && crs->hi < ers->lo - 1)
281: break;
282: /* This entry overlaps. */
283: if (crs->lo < ers->lo) {
284: ers->lo = crs->lo;
285: KRL_DBG(("%s: pred extend %llu:%llu", __func__,
286: ers->lo, ers->hi));
287: }
288: RB_REMOVE(revoked_serial_tree, rt, crs);
289: free(crs);
290: }
291: /* Check successors */
292: while ((crs = RB_NEXT(revoked_serial_tree, rt, ers)) != NULL) {
293: KRL_DBG(("%s: succ %llu:%llu", __func__, crs->lo, crs->hi));
294: if (ers->hi != (u_int64_t)-1 && crs->lo > ers->hi + 1)
295: break;
296: /* This entry overlaps. */
297: if (crs->hi > ers->hi) {
298: ers->hi = crs->hi;
299: KRL_DBG(("%s: succ extend %llu:%llu", __func__,
300: ers->lo, ers->hi));
301: }
302: RB_REMOVE(revoked_serial_tree, rt, crs);
303: free(crs);
304: }
305: KRL_DBG(("%s: done, final %llu:%llu", __func__, ers->lo, ers->hi));
306: return 0;
307: }
308:
309: int
1.20 djm 310: ssh_krl_revoke_cert_by_serial(struct ssh_krl *krl, const struct sshkey *ca_key,
1.1 djm 311: u_int64_t serial)
312: {
313: return ssh_krl_revoke_cert_by_serial_range(krl, ca_key, serial, serial);
314: }
315:
316: int
1.25 ! djm 317: ssh_krl_revoke_cert_by_serial_range(struct ssh_krl *krl,
! 318: const struct sshkey *ca_key, u_int64_t lo, u_int64_t hi)
1.1 djm 319: {
320: struct revoked_certs *rc;
1.20 djm 321: int r;
1.1 djm 322:
323: if (lo > hi || lo == 0)
1.25 ! djm 324: return SSH_ERR_INVALID_ARGUMENT;
1.20 djm 325: if ((r = revoked_certs_for_ca_key(krl, ca_key, &rc, 1)) != 0)
326: return r;
1.1 djm 327: return insert_serial_range(&rc->revoked_serials, lo, hi);
328: }
329:
330: int
1.20 djm 331: ssh_krl_revoke_cert_by_key_id(struct ssh_krl *krl, const struct sshkey *ca_key,
1.1 djm 332: const char *key_id)
333: {
334: struct revoked_key_id *rki, *erki;
335: struct revoked_certs *rc;
1.20 djm 336: int r;
1.1 djm 337:
1.20 djm 338: if ((r = revoked_certs_for_ca_key(krl, ca_key, &rc, 1)) != 0)
339: return r;
1.1 djm 340:
1.25 ! djm 341: KRL_DBG(("%s: revoke %s", __func__, key_id));
1.1 djm 342: if ((rki = calloc(1, sizeof(*rki))) == NULL ||
343: (rki->key_id = strdup(key_id)) == NULL) {
344: free(rki);
1.20 djm 345: return SSH_ERR_ALLOC_FAIL;
1.1 djm 346: }
347: erki = RB_INSERT(revoked_key_id_tree, &rc->revoked_key_ids, rki);
348: if (erki != NULL) {
349: free(rki->key_id);
350: free(rki);
351: }
352: return 0;
353: }
354:
355: /* Convert "key" to a public key blob without any certificate information */
356: static int
1.20 djm 357: plain_key_blob(const struct sshkey *key, u_char **blob, size_t *blen)
1.1 djm 358: {
1.20 djm 359: struct sshkey *kcopy;
1.1 djm 360: int r;
361:
1.20 djm 362: if ((r = sshkey_from_private(key, &kcopy)) != 0)
363: return r;
364: if (sshkey_is_cert(kcopy)) {
365: if ((r = sshkey_drop_cert(kcopy)) != 0) {
366: sshkey_free(kcopy);
367: return r;
1.1 djm 368: }
369: }
1.20 djm 370: r = sshkey_to_blob(kcopy, blob, blen);
1.23 markus 371: sshkey_free(kcopy);
1.17 djm 372: return r;
1.1 djm 373: }
374:
375: /* Revoke a key blob. Ownership of blob is transferred to the tree */
376: static int
1.25 ! djm 377: revoke_blob(struct revoked_blob_tree *rbt, u_char *blob, size_t len)
1.1 djm 378: {
379: struct revoked_blob *rb, *erb;
380:
381: if ((rb = calloc(1, sizeof(*rb))) == NULL)
1.20 djm 382: return SSH_ERR_ALLOC_FAIL;
1.1 djm 383: rb->blob = blob;
384: rb->len = len;
385: erb = RB_INSERT(revoked_blob_tree, rbt, rb);
386: if (erb != NULL) {
387: free(rb->blob);
388: free(rb);
389: }
390: return 0;
391: }
392:
393: int
1.20 djm 394: ssh_krl_revoke_key_explicit(struct ssh_krl *krl, const struct sshkey *key)
1.1 djm 395: {
396: u_char *blob;
1.20 djm 397: size_t len;
398: int r;
1.1 djm 399:
1.20 djm 400: debug3("%s: revoke type %s", __func__, sshkey_type(key));
401: if ((r = plain_key_blob(key, &blob, &len)) != 0)
402: return r;
1.1 djm 403: return revoke_blob(&krl->revoked_keys, blob, len);
404: }
405:
406: int
1.20 djm 407: ssh_krl_revoke_key_sha1(struct ssh_krl *krl, const struct sshkey *key)
1.1 djm 408: {
409: u_char *blob;
1.20 djm 410: size_t len;
411: int r;
1.1 djm 412:
1.20 djm 413: debug3("%s: revoke type %s by sha1", __func__, sshkey_type(key));
1.21 djm 414: if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA1,
415: &blob, &len)) != 0)
1.20 djm 416: return r;
1.1 djm 417: return revoke_blob(&krl->revoked_sha1s, blob, len);
418: }
419:
420: int
1.20 djm 421: ssh_krl_revoke_key(struct ssh_krl *krl, const struct sshkey *key)
1.1 djm 422: {
1.20 djm 423: if (!sshkey_is_cert(key))
1.1 djm 424: return ssh_krl_revoke_key_sha1(krl, key);
425:
1.20 djm 426: if (sshkey_cert_is_legacy(key) || key->cert->serial == 0) {
1.1 djm 427: return ssh_krl_revoke_cert_by_key_id(krl,
428: key->cert->signature_key,
429: key->cert->key_id);
430: } else {
431: return ssh_krl_revoke_cert_by_serial(krl,
432: key->cert->signature_key,
433: key->cert->serial);
434: }
435: }
436:
437: /*
1.20 djm 438: * Select the most compact section type to emit next in a KRL based on
439: * the current section type, the run length of contiguous revoked serial
1.1 djm 440: * numbers and the gaps from the last and to the next revoked serial.
441: * Applies a mostly-accurate bit cost model to select the section type
442: * that will minimise the size of the resultant KRL.
443: */
444: static int
445: choose_next_state(int current_state, u_int64_t contig, int final,
446: u_int64_t last_gap, u_int64_t next_gap, int *force_new_section)
447: {
448: int new_state;
449: u_int64_t cost, cost_list, cost_range, cost_bitmap, cost_bitmap_restart;
450:
451: /*
452: * Avoid unsigned overflows.
453: * The limits are high enough to avoid confusing the calculations.
454: */
455: contig = MIN(contig, 1ULL<<31);
456: last_gap = MIN(last_gap, 1ULL<<31);
457: next_gap = MIN(next_gap, 1ULL<<31);
458:
459: /*
460: * Calculate the cost to switch from the current state to candidates.
461: * NB. range sections only ever contain a single range, so their
462: * switching cost is independent of the current_state.
463: */
464: cost_list = cost_bitmap = cost_bitmap_restart = 0;
465: cost_range = 8;
466: switch (current_state) {
467: case KRL_SECTION_CERT_SERIAL_LIST:
468: cost_bitmap_restart = cost_bitmap = 8 + 64;
469: break;
470: case KRL_SECTION_CERT_SERIAL_BITMAP:
471: cost_list = 8;
472: cost_bitmap_restart = 8 + 64;
473: break;
474: case KRL_SECTION_CERT_SERIAL_RANGE:
475: case 0:
476: cost_bitmap_restart = cost_bitmap = 8 + 64;
477: cost_list = 8;
478: }
479:
480: /* Estimate base cost in bits of each section type */
481: cost_list += 64 * contig + (final ? 0 : 8+64);
482: cost_range += (2 * 64) + (final ? 0 : 8+64);
483: cost_bitmap += last_gap + contig + (final ? 0 : MIN(next_gap, 8+64));
484: cost_bitmap_restart += contig + (final ? 0 : MIN(next_gap, 8+64));
485:
486: /* Convert to byte costs for actual comparison */
487: cost_list = (cost_list + 7) / 8;
488: cost_bitmap = (cost_bitmap + 7) / 8;
489: cost_bitmap_restart = (cost_bitmap_restart + 7) / 8;
490: cost_range = (cost_range + 7) / 8;
491:
492: /* Now pick the best choice */
493: *force_new_section = 0;
494: new_state = KRL_SECTION_CERT_SERIAL_BITMAP;
495: cost = cost_bitmap;
496: if (cost_range < cost) {
497: new_state = KRL_SECTION_CERT_SERIAL_RANGE;
498: cost = cost_range;
499: }
500: if (cost_list < cost) {
501: new_state = KRL_SECTION_CERT_SERIAL_LIST;
502: cost = cost_list;
503: }
504: if (cost_bitmap_restart < cost) {
505: new_state = KRL_SECTION_CERT_SERIAL_BITMAP;
506: *force_new_section = 1;
507: cost = cost_bitmap_restart;
508: }
1.25 ! djm 509: KRL_DBG(("%s: contig %llu last_gap %llu next_gap %llu final %d, costs:"
1.1 djm 510: "list %llu range %llu bitmap %llu new bitmap %llu, "
1.11 djm 511: "selected 0x%02x%s", __func__, (long long unsigned)contig,
512: (long long unsigned)last_gap, (long long unsigned)next_gap, final,
513: (long long unsigned)cost_list, (long long unsigned)cost_range,
514: (long long unsigned)cost_bitmap,
515: (long long unsigned)cost_bitmap_restart, new_state,
1.25 ! djm 516: *force_new_section ? " restart" : ""));
1.1 djm 517: return new_state;
518: }
519:
520: /* Generate a KRL_SECTION_CERTIFICATES KRL section */
521: static int
1.20 djm 522: revoked_certs_generate(struct revoked_certs *rc, struct sshbuf *buf)
1.1 djm 523: {
1.25 ! djm 524: int final, force_new_sect, r = SSH_ERR_INTERNAL_ERROR;
1.1 djm 525: u_int64_t i, contig, gap, last = 0, bitmap_start = 0;
526: struct revoked_serial *rs, *nrs;
527: struct revoked_key_id *rki;
528: int next_state, state = 0;
1.20 djm 529: struct sshbuf *sect;
1.1 djm 530: BIGNUM *bitmap = NULL;
531:
1.20 djm 532: if ((sect = sshbuf_new()) == NULL)
533: return SSH_ERR_ALLOC_FAIL;
1.1 djm 534:
1.20 djm 535: /* Store the header: CA scope key, reserved */
536: if ((r = sshkey_to_blob_buf(rc->ca_key, sect)) != 0 ||
537: (r = sshbuf_put_stringb(buf, sect)) != 0 ||
538: (r = sshbuf_put_string(buf, NULL, 0)) != 0)
539: goto out;
1.1 djm 540:
1.20 djm 541: sshbuf_reset(sect);
1.1 djm 542:
543: /* Store the revoked serials. */
544: for (rs = RB_MIN(revoked_serial_tree, &rc->revoked_serials);
545: rs != NULL;
546: rs = RB_NEXT(revoked_serial_tree, &rc->revoked_serials, rs)) {
1.25 ! djm 547: KRL_DBG(("%s: serial %llu:%llu state 0x%02x", __func__,
1.11 djm 548: (long long unsigned)rs->lo, (long long unsigned)rs->hi,
1.25 ! djm 549: state));
1.1 djm 550:
551: /* Check contiguous length and gap to next section (if any) */
552: nrs = RB_NEXT(revoked_serial_tree, &rc->revoked_serials, rs);
553: final = nrs == NULL;
554: gap = nrs == NULL ? 0 : nrs->lo - rs->hi;
555: contig = 1 + (rs->hi - rs->lo);
556:
557: /* Choose next state based on these */
558: next_state = choose_next_state(state, contig, final,
559: state == 0 ? 0 : rs->lo - last, gap, &force_new_sect);
560:
561: /*
562: * If the current section is a range section or has a different
563: * type to the next section, then finish it off now.
564: */
565: if (state != 0 && (force_new_sect || next_state != state ||
566: state == KRL_SECTION_CERT_SERIAL_RANGE)) {
1.25 ! djm 567: KRL_DBG(("%s: finish state 0x%02x", __func__, state));
1.1 djm 568: switch (state) {
569: case KRL_SECTION_CERT_SERIAL_LIST:
570: case KRL_SECTION_CERT_SERIAL_RANGE:
571: break;
572: case KRL_SECTION_CERT_SERIAL_BITMAP:
1.20 djm 573: if ((r = sshbuf_put_bignum2(sect, bitmap)) != 0)
574: goto out;
1.1 djm 575: BN_free(bitmap);
576: bitmap = NULL;
577: break;
578: }
1.20 djm 579: if ((r = sshbuf_put_u8(buf, state)) != 0 ||
580: (r = sshbuf_put_stringb(buf, sect)) != 0)
581: goto out;
582: sshbuf_reset(sect);
1.1 djm 583: }
584:
585: /* If we are starting a new section then prepare it now */
586: if (next_state != state || force_new_sect) {
1.25 ! djm 587: KRL_DBG(("%s: start state 0x%02x", __func__,
! 588: next_state));
1.1 djm 589: state = next_state;
1.20 djm 590: sshbuf_reset(sect);
1.1 djm 591: switch (state) {
592: case KRL_SECTION_CERT_SERIAL_LIST:
593: case KRL_SECTION_CERT_SERIAL_RANGE:
594: break;
595: case KRL_SECTION_CERT_SERIAL_BITMAP:
1.20 djm 596: if ((bitmap = BN_new()) == NULL) {
597: r = SSH_ERR_ALLOC_FAIL;
1.1 djm 598: goto out;
1.20 djm 599: }
1.1 djm 600: bitmap_start = rs->lo;
1.20 djm 601: if ((r = sshbuf_put_u64(sect,
602: bitmap_start)) != 0)
603: goto out;
1.1 djm 604: break;
605: }
606: }
607:
608: /* Perform section-specific processing */
609: switch (state) {
610: case KRL_SECTION_CERT_SERIAL_LIST:
1.20 djm 611: for (i = 0; i < contig; i++) {
612: if ((r = sshbuf_put_u64(sect, rs->lo + i)) != 0)
613: goto out;
614: }
1.1 djm 615: break;
616: case KRL_SECTION_CERT_SERIAL_RANGE:
1.20 djm 617: if ((r = sshbuf_put_u64(sect, rs->lo)) != 0 ||
618: (r = sshbuf_put_u64(sect, rs->hi)) != 0)
619: goto out;
1.1 djm 620: break;
621: case KRL_SECTION_CERT_SERIAL_BITMAP:
622: if (rs->lo - bitmap_start > INT_MAX) {
623: error("%s: insane bitmap gap", __func__);
624: goto out;
625: }
626: for (i = 0; i < contig; i++) {
627: if (BN_set_bit(bitmap,
1.20 djm 628: rs->lo + i - bitmap_start) != 1) {
629: r = SSH_ERR_ALLOC_FAIL;
1.1 djm 630: goto out;
1.20 djm 631: }
1.1 djm 632: }
633: break;
634: }
635: last = rs->hi;
636: }
637: /* Flush the remaining section, if any */
638: if (state != 0) {
1.25 ! djm 639: KRL_DBG(("%s: serial final flush for state 0x%02x",
! 640: __func__, state));
1.1 djm 641: switch (state) {
642: case KRL_SECTION_CERT_SERIAL_LIST:
643: case KRL_SECTION_CERT_SERIAL_RANGE:
644: break;
645: case KRL_SECTION_CERT_SERIAL_BITMAP:
1.20 djm 646: if ((r = sshbuf_put_bignum2(sect, bitmap)) != 0)
647: goto out;
1.1 djm 648: BN_free(bitmap);
649: bitmap = NULL;
650: break;
651: }
1.20 djm 652: if ((r = sshbuf_put_u8(buf, state)) != 0 ||
653: (r = sshbuf_put_stringb(buf, sect)) != 0)
654: goto out;
1.1 djm 655: }
1.25 ! djm 656: KRL_DBG(("%s: serial done ", __func__));
1.1 djm 657:
658: /* Now output a section for any revocations by key ID */
1.20 djm 659: sshbuf_reset(sect);
1.1 djm 660: RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) {
1.25 ! djm 661: KRL_DBG(("%s: key ID %s", __func__, rki->key_id));
1.20 djm 662: if ((r = sshbuf_put_cstring(sect, rki->key_id)) != 0)
663: goto out;
1.1 djm 664: }
1.20 djm 665: if (sshbuf_len(sect) != 0) {
666: if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERT_KEY_ID)) != 0 ||
667: (r = sshbuf_put_stringb(buf, sect)) != 0)
668: goto out;
1.1 djm 669: }
670: r = 0;
671: out:
672: if (bitmap != NULL)
673: BN_free(bitmap);
1.20 djm 674: sshbuf_free(sect);
1.1 djm 675: return r;
676: }
677:
678: int
1.20 djm 679: ssh_krl_to_blob(struct ssh_krl *krl, struct sshbuf *buf,
680: const struct sshkey **sign_keys, u_int nsign_keys)
1.1 djm 681: {
1.25 ! djm 682: int r = SSH_ERR_INTERNAL_ERROR;
1.1 djm 683: struct revoked_certs *rc;
684: struct revoked_blob *rb;
1.20 djm 685: struct sshbuf *sect;
686: u_char *sblob = NULL;
687: size_t slen, i;
1.1 djm 688:
689: if (krl->generated_date == 0)
690: krl->generated_date = time(NULL);
691:
1.20 djm 692: if ((sect = sshbuf_new()) == NULL)
693: return SSH_ERR_ALLOC_FAIL;
1.1 djm 694:
695: /* Store the header */
1.20 djm 696: if ((r = sshbuf_put(buf, KRL_MAGIC, sizeof(KRL_MAGIC) - 1)) != 0 ||
697: (r = sshbuf_put_u32(buf, KRL_FORMAT_VERSION)) != 0 ||
698: (r = sshbuf_put_u64(buf, krl->krl_version)) != 0 ||
699: (r = sshbuf_put_u64(buf, krl->generated_date) != 0) ||
700: (r = sshbuf_put_u64(buf, krl->flags)) != 0 ||
701: (r = sshbuf_put_string(buf, NULL, 0)) != 0 ||
702: (r = sshbuf_put_cstring(buf, krl->comment)) != 0)
703: goto out;
1.1 djm 704:
705: /* Store sections for revoked certificates */
706: TAILQ_FOREACH(rc, &krl->revoked_certs, entry) {
1.20 djm 707: sshbuf_reset(sect);
708: if ((r = revoked_certs_generate(rc, sect)) != 0)
709: goto out;
710: if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERTIFICATES)) != 0 ||
711: (r = sshbuf_put_stringb(buf, sect)) != 0)
1.1 djm 712: goto out;
713: }
714:
715: /* Finally, output sections for revocations by public key/hash */
1.20 djm 716: sshbuf_reset(sect);
1.1 djm 717: RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) {
1.25 ! djm 718: KRL_DBG(("%s: key len %u ", __func__, rb->len));
1.24 markus 719: if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0)
1.20 djm 720: goto out;
1.1 djm 721: }
1.20 djm 722: if (sshbuf_len(sect) != 0) {
723: if ((r = sshbuf_put_u8(buf, KRL_SECTION_EXPLICIT_KEY)) != 0 ||
724: (r = sshbuf_put_stringb(buf, sect)) != 0)
725: goto out;
1.1 djm 726: }
1.20 djm 727: sshbuf_reset(sect);
1.1 djm 728: RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) {
1.25 ! djm 729: KRL_DBG(("%s: hash len %u ", __func__, rb->len));
1.24 markus 730: if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0)
1.20 djm 731: goto out;
1.1 djm 732: }
1.20 djm 733: if (sshbuf_len(sect) != 0) {
734: if ((r = sshbuf_put_u8(buf,
735: KRL_SECTION_FINGERPRINT_SHA1)) != 0 ||
736: (r = sshbuf_put_stringb(buf, sect)) != 0)
737: goto out;
1.1 djm 738: }
739:
740: for (i = 0; i < nsign_keys; i++) {
1.20 djm 741: sshbuf_reset(sect);
742: if ((r = sshkey_to_blob_buf(sign_keys[i], sect)) != 0)
1.1 djm 743: goto out;
744:
1.25 ! djm 745: KRL_DBG(("%s: signature key len %zu", __func__,
! 746: sshbuf_len(sect)));
1.20 djm 747: if ((r = sshbuf_put_u8(buf, KRL_SECTION_SIGNATURE)) != 0 ||
748: (r = sshbuf_put_stringb(buf, sect)) != 0)
749: goto out;
1.1 djm 750:
1.20 djm 751: if ((r = sshkey_sign(sign_keys[i], &sblob, &slen,
752: sshbuf_ptr(buf), sshbuf_len(buf), 0)) == -1)
753: goto out;
1.25 ! djm 754: KRL_DBG(("%s: signature sig len %u", __func__, slen));
1.20 djm 755: if ((r = sshbuf_put_string(buf, sblob, slen)) != 0)
1.1 djm 756: goto out;
757: }
758:
759: r = 0;
760: out:
761: free(sblob);
1.20 djm 762: sshbuf_free(sect);
1.1 djm 763: return r;
764: }
765:
766: static void
767: format_timestamp(u_int64_t timestamp, char *ts, size_t nts)
768: {
769: time_t t;
770: struct tm *tm;
771:
772: t = timestamp;
773: tm = localtime(&t);
1.19 djm 774: if (tm == NULL)
775: strlcpy(ts, "<INVALID>", sizeof(nts));
776: else {
777: *ts = '\0';
778: strftime(ts, nts, "%Y%m%dT%H%M%S", tm);
779: }
1.1 djm 780: }
781:
782: static int
1.20 djm 783: parse_revoked_certs(struct sshbuf *buf, struct ssh_krl *krl)
1.1 djm 784: {
1.25 ! djm 785: int r = SSH_ERR_INTERNAL_ERROR, nbits;
1.15 djm 786: u_char type;
787: const u_char *blob;
1.20 djm 788: size_t blen;
789: struct sshbuf *subsect = NULL;
1.1 djm 790: u_int64_t serial, serial_lo, serial_hi;
791: BIGNUM *bitmap = NULL;
792: char *key_id = NULL;
1.20 djm 793: struct sshkey *ca_key = NULL;
1.1 djm 794:
1.20 djm 795: if ((subsect = sshbuf_new()) == NULL)
796: return SSH_ERR_ALLOC_FAIL;
1.1 djm 797:
1.20 djm 798: /* Header: key, reserved */
799: if ((r = sshbuf_get_string_direct(buf, &blob, &blen)) != 0 ||
800: (r = sshbuf_skip_string(buf)) != 0)
1.1 djm 801: goto out;
1.20 djm 802: if ((r = sshkey_from_blob(blob, blen, &ca_key)) != 0)
1.1 djm 803: goto out;
804:
1.20 djm 805: while (sshbuf_len(buf) > 0) {
806: if (subsect != NULL) {
807: sshbuf_free(subsect);
808: subsect = NULL;
809: }
810: if ((r = sshbuf_get_u8(buf, &type)) != 0 ||
811: (r = sshbuf_froms(buf, &subsect)) != 0)
1.1 djm 812: goto out;
1.25 ! djm 813: KRL_DBG(("%s: subsection type 0x%02x", __func__, type));
! 814: /* sshbuf_dump(subsect, stderr); */
1.1 djm 815:
816: switch (type) {
817: case KRL_SECTION_CERT_SERIAL_LIST:
1.20 djm 818: while (sshbuf_len(subsect) > 0) {
819: if ((r = sshbuf_get_u64(subsect, &serial)) != 0)
1.1 djm 820: goto out;
1.20 djm 821: if ((r = ssh_krl_revoke_cert_by_serial(krl,
822: ca_key, serial)) != 0)
1.1 djm 823: goto out;
824: }
825: break;
826: case KRL_SECTION_CERT_SERIAL_RANGE:
1.20 djm 827: if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 ||
828: (r = sshbuf_get_u64(subsect, &serial_hi)) != 0)
1.1 djm 829: goto out;
1.20 djm 830: if ((r = ssh_krl_revoke_cert_by_serial_range(krl,
831: ca_key, serial_lo, serial_hi)) != 0)
1.1 djm 832: goto out;
833: break;
834: case KRL_SECTION_CERT_SERIAL_BITMAP:
835: if ((bitmap = BN_new()) == NULL) {
1.20 djm 836: r = SSH_ERR_ALLOC_FAIL;
1.1 djm 837: goto out;
838: }
1.20 djm 839: if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 ||
840: (r = sshbuf_get_bignum2(subsect, bitmap)) != 0)
1.1 djm 841: goto out;
842: if ((nbits = BN_num_bits(bitmap)) < 0) {
843: error("%s: bitmap bits < 0", __func__);
1.20 djm 844: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 845: goto out;
846: }
1.25 ! djm 847: for (serial = 0; serial < (u_int64_t)nbits; serial++) {
1.1 djm 848: if (serial > 0 && serial_lo + serial == 0) {
849: error("%s: bitmap wraps u64", __func__);
1.20 djm 850: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 851: goto out;
852: }
853: if (!BN_is_bit_set(bitmap, serial))
854: continue;
1.20 djm 855: if ((r = ssh_krl_revoke_cert_by_serial(krl,
856: ca_key, serial_lo + serial)) != 0)
1.1 djm 857: goto out;
858: }
859: BN_free(bitmap);
860: bitmap = NULL;
861: break;
862: case KRL_SECTION_CERT_KEY_ID:
1.20 djm 863: while (sshbuf_len(subsect) > 0) {
864: if ((r = sshbuf_get_cstring(subsect,
865: &key_id, NULL)) != 0)
1.1 djm 866: goto out;
1.20 djm 867: if ((r = ssh_krl_revoke_cert_by_key_id(krl,
868: ca_key, key_id)) != 0)
1.1 djm 869: goto out;
870: free(key_id);
871: key_id = NULL;
872: }
873: break;
874: default:
875: error("Unsupported KRL certificate section %u", type);
1.20 djm 876: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 877: goto out;
878: }
1.20 djm 879: if (sshbuf_len(subsect) > 0) {
1.1 djm 880: error("KRL certificate section contains unparsed data");
1.20 djm 881: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 882: goto out;
883: }
884: }
885:
1.20 djm 886: r = 0;
1.1 djm 887: out:
888: if (bitmap != NULL)
889: BN_free(bitmap);
890: free(key_id);
1.20 djm 891: sshkey_free(ca_key);
892: sshbuf_free(subsect);
893: return r;
1.1 djm 894: }
895:
896:
897: /* Attempt to parse a KRL, checking its signature (if any) with sign_ca_keys. */
898: int
1.20 djm 899: ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp,
1.25 ! djm 900: const struct sshkey **sign_ca_keys, size_t nsign_ca_keys)
1.1 djm 901: {
1.20 djm 902: struct sshbuf *copy = NULL, *sect = NULL;
903: struct ssh_krl *krl = NULL;
1.1 djm 904: char timestamp[64];
1.25 ! djm 905: int r = SSH_ERR_INTERNAL_ERROR, sig_seen;
1.20 djm 906: struct sshkey *key = NULL, **ca_used = NULL, **tmp_ca_used;
1.15 djm 907: u_char type, *rdata = NULL;
908: const u_char *blob;
1.20 djm 909: size_t i, j, sig_off, sects_off, rlen, blen, nca_used;
910: u_int format_version;
1.1 djm 911:
1.12 markus 912: nca_used = 0;
1.1 djm 913: *krlp = NULL;
1.20 djm 914: if (sshbuf_len(buf) < sizeof(KRL_MAGIC) - 1 ||
915: memcmp(sshbuf_ptr(buf), KRL_MAGIC, sizeof(KRL_MAGIC) - 1) != 0) {
1.1 djm 916: debug3("%s: not a KRL", __func__);
1.20 djm 917: return SSH_ERR_KRL_BAD_MAGIC;
1.1 djm 918: }
919:
920: /* Take a copy of the KRL buffer so we can verify its signature later */
1.20 djm 921: if ((copy = sshbuf_fromb(buf)) == NULL) {
922: r = SSH_ERR_ALLOC_FAIL;
923: goto out;
924: }
925: if ((r = sshbuf_consume(copy, sizeof(KRL_MAGIC) - 1)) != 0)
926: goto out;
1.1 djm 927:
928: if ((krl = ssh_krl_init()) == NULL) {
929: error("%s: alloc failed", __func__);
930: goto out;
931: }
932:
1.20 djm 933: if ((r = sshbuf_get_u32(copy, &format_version)) != 0)
1.1 djm 934: goto out;
935: if (format_version != KRL_FORMAT_VERSION) {
1.20 djm 936: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 937: goto out;
938: }
1.20 djm 939: if ((r = sshbuf_get_u64(copy, &krl->krl_version)) != 0 ||
940: (r = sshbuf_get_u64(copy, &krl->generated_date)) != 0 ||
941: (r = sshbuf_get_u64(copy, &krl->flags)) != 0 ||
942: (r = sshbuf_skip_string(copy)) != 0 ||
943: (r = sshbuf_get_cstring(copy, &krl->comment, NULL)) != 0)
1.1 djm 944: goto out;
945:
946: format_timestamp(krl->generated_date, timestamp, sizeof(timestamp));
1.11 djm 947: debug("KRL version %llu generated at %s%s%s",
948: (long long unsigned)krl->krl_version, timestamp,
949: *krl->comment ? ": " : "", krl->comment);
1.1 djm 950:
951: /*
952: * 1st pass: verify signatures, if any. This is done to avoid
953: * detailed parsing of data whose provenance is unverified.
954: */
955: sig_seen = 0;
1.20 djm 956: if (sshbuf_len(buf) < sshbuf_len(copy)) {
957: /* Shouldn't happen */
958: r = SSH_ERR_INTERNAL_ERROR;
959: goto out;
960: }
961: sects_off = sshbuf_len(buf) - sshbuf_len(copy);
962: while (sshbuf_len(copy) > 0) {
963: if ((r = sshbuf_get_u8(copy, &type)) != 0 ||
964: (r = sshbuf_get_string_direct(copy, &blob, &blen)) != 0)
1.1 djm 965: goto out;
1.25 ! djm 966: KRL_DBG(("%s: first pass, section 0x%02x", __func__, type));
1.1 djm 967: if (type != KRL_SECTION_SIGNATURE) {
968: if (sig_seen) {
969: error("KRL contains non-signature section "
970: "after signature");
1.25 ! djm 971: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 972: goto out;
973: }
974: /* Not interested for now. */
975: continue;
976: }
977: sig_seen = 1;
978: /* First string component is the signing key */
1.20 djm 979: if ((r = sshkey_from_blob(blob, blen, &key)) != 0) {
980: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 981: goto out;
982: }
1.20 djm 983: if (sshbuf_len(buf) < sshbuf_len(copy)) {
984: /* Shouldn't happen */
985: r = SSH_ERR_INTERNAL_ERROR;
986: goto out;
987: }
988: sig_off = sshbuf_len(buf) - sshbuf_len(copy);
1.1 djm 989: /* Second string component is the signature itself */
1.20 djm 990: if ((r = sshbuf_get_string_direct(copy, &blob, &blen)) != 0) {
991: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 992: goto out;
993: }
994: /* Check signature over entire KRL up to this point */
1.20 djm 995: if ((r = sshkey_verify(key, blob, blen,
1.25 ! djm 996: sshbuf_ptr(buf), sshbuf_len(buf) - sig_off, 0)) != 0)
1.1 djm 997: goto out;
998: /* Check if this key has already signed this KRL */
999: for (i = 0; i < nca_used; i++) {
1.20 djm 1000: if (sshkey_equal(ca_used[i], key)) {
1.1 djm 1001: error("KRL signed more than once with "
1002: "the same key");
1.25 ! djm 1003: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 1004: goto out;
1005: }
1006: }
1007: /* Record keys used to sign the KRL */
1.20 djm 1008: tmp_ca_used = reallocarray(ca_used, nca_used + 1,
1009: sizeof(*ca_used));
1010: if (tmp_ca_used == NULL) {
1011: r = SSH_ERR_ALLOC_FAIL;
1012: goto out;
1013: }
1014: ca_used = tmp_ca_used;
1.1 djm 1015: ca_used[nca_used++] = key;
1016: key = NULL;
1017: break;
1018: }
1019:
1.20 djm 1020: if (sshbuf_len(copy) != 0) {
1021: /* Shouldn't happen */
1022: r = SSH_ERR_INTERNAL_ERROR;
1023: goto out;
1024: }
1025:
1.1 djm 1026: /*
1027: * 2nd pass: parse and load the KRL, skipping the header to the point
1028: * where the section start.
1029: */
1.20 djm 1030: sshbuf_free(copy);
1031: if ((copy = sshbuf_fromb(buf)) == NULL) {
1032: r = SSH_ERR_ALLOC_FAIL;
1033: goto out;
1034: }
1035: if ((r = sshbuf_consume(copy, sects_off)) != 0)
1036: goto out;
1037: while (sshbuf_len(copy) > 0) {
1038: if (sect != NULL) {
1039: sshbuf_free(sect);
1040: sect = NULL;
1041: }
1042: if ((r = sshbuf_get_u8(copy, &type)) != 0 ||
1.25 ! djm 1043: (r = sshbuf_froms(copy, §)) != 0)
1.1 djm 1044: goto out;
1.25 ! djm 1045: KRL_DBG(("%s: second pass, section 0x%02x", __func__, type));
1.1 djm 1046:
1047: switch (type) {
1048: case KRL_SECTION_CERTIFICATES:
1.20 djm 1049: if ((r = parse_revoked_certs(sect, krl)) != 0)
1.1 djm 1050: goto out;
1051: break;
1052: case KRL_SECTION_EXPLICIT_KEY:
1053: case KRL_SECTION_FINGERPRINT_SHA1:
1.20 djm 1054: while (sshbuf_len(sect) > 0) {
1055: if ((r = sshbuf_get_string(sect,
1056: &rdata, &rlen)) != 0)
1.1 djm 1057: goto out;
1058: if (type == KRL_SECTION_FINGERPRINT_SHA1 &&
1.12 markus 1059: rlen != 20) {
1.1 djm 1060: error("%s: bad SHA1 length", __func__);
1.20 djm 1061: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 1062: goto out;
1063: }
1.20 djm 1064: if ((r = revoke_blob(
1.1 djm 1065: type == KRL_SECTION_EXPLICIT_KEY ?
1066: &krl->revoked_keys : &krl->revoked_sha1s,
1.20 djm 1067: rdata, rlen)) != 0)
1.12 markus 1068: goto out;
1.25 ! djm 1069: rdata = NULL; /* revoke_blob frees rdata */
1.1 djm 1070: }
1071: break;
1072: case KRL_SECTION_SIGNATURE:
1073: /* Handled above, but still need to stay in synch */
1.20 djm 1074: sshbuf_reset(sect);
1075: sect = NULL;
1076: if ((r = sshbuf_skip_string(copy)) != 0)
1.1 djm 1077: goto out;
1078: break;
1079: default:
1080: error("Unsupported KRL section %u", type);
1.20 djm 1081: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 1082: goto out;
1083: }
1.20 djm 1084: if (sshbuf_len(sect) > 0) {
1.1 djm 1085: error("KRL section contains unparsed data");
1.20 djm 1086: r = SSH_ERR_INVALID_FORMAT;
1.1 djm 1087: goto out;
1088: }
1089: }
1090:
1091: /* Check that the key(s) used to sign the KRL weren't revoked */
1092: sig_seen = 0;
1093: for (i = 0; i < nca_used; i++) {
1094: if (ssh_krl_check_key(krl, ca_used[i]) == 0)
1095: sig_seen = 1;
1096: else {
1.20 djm 1097: sshkey_free(ca_used[i]);
1.1 djm 1098: ca_used[i] = NULL;
1099: }
1100: }
1101: if (nca_used && !sig_seen) {
1102: error("All keys used to sign KRL were revoked");
1.25 ! djm 1103: r = SSH_ERR_KEY_REVOKED;
1.1 djm 1104: goto out;
1105: }
1106:
1107: /* If we have CA keys, then verify that one was used to sign the KRL */
1108: if (sig_seen && nsign_ca_keys != 0) {
1109: sig_seen = 0;
1110: for (i = 0; !sig_seen && i < nsign_ca_keys; i++) {
1111: for (j = 0; j < nca_used; j++) {
1112: if (ca_used[j] == NULL)
1113: continue;
1.20 djm 1114: if (sshkey_equal(ca_used[j], sign_ca_keys[i])) {
1.1 djm 1115: sig_seen = 1;
1116: break;
1117: }
1118: }
1119: }
1120: if (!sig_seen) {
1.20 djm 1121: r = SSH_ERR_SIGNATURE_INVALID;
1.1 djm 1122: error("KRL not signed with any trusted key");
1123: goto out;
1124: }
1125: }
1126:
1127: *krlp = krl;
1.20 djm 1128: r = 0;
1.1 djm 1129: out:
1.20 djm 1130: if (r != 0)
1.1 djm 1131: ssh_krl_free(krl);
1.20 djm 1132: for (i = 0; i < nca_used; i++)
1133: sshkey_free(ca_used[i]);
1.1 djm 1134: free(ca_used);
1.12 markus 1135: free(rdata);
1.20 djm 1136: sshkey_free(key);
1137: sshbuf_free(copy);
1138: sshbuf_free(sect);
1139: return r;
1.1 djm 1140: }
1141:
1142: /* Checks whether a given key/cert is revoked. Does not check its CA */
1143: static int
1.20 djm 1144: is_key_revoked(struct ssh_krl *krl, const struct sshkey *key)
1.1 djm 1145: {
1146: struct revoked_blob rb, *erb;
1147: struct revoked_serial rs, *ers;
1148: struct revoked_key_id rki, *erki;
1149: struct revoked_certs *rc;
1.20 djm 1150: int r;
1.1 djm 1151:
1152: /* Check explicitly revoked hashes first */
1.14 tedu 1153: memset(&rb, 0, sizeof(rb));
1.21 djm 1154: if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA1,
1.20 djm 1155: &rb.blob, &rb.len)) != 0)
1156: return r;
1.1 djm 1157: erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha1s, &rb);
1158: free(rb.blob);
1159: if (erb != NULL) {
1.25 ! djm 1160: KRL_DBG(("%s: revoked by key SHA1", __func__));
1.20 djm 1161: return SSH_ERR_KEY_REVOKED;
1.1 djm 1162: }
1163:
1164: /* Next, explicit keys */
1.14 tedu 1165: memset(&rb, 0, sizeof(rb));
1.20 djm 1166: if ((r = plain_key_blob(key, &rb.blob, &rb.len)) != 0)
1167: return r;
1.1 djm 1168: erb = RB_FIND(revoked_blob_tree, &krl->revoked_keys, &rb);
1169: free(rb.blob);
1170: if (erb != NULL) {
1.25 ! djm 1171: KRL_DBG(("%s: revoked by explicit key", __func__));
1.20 djm 1172: return SSH_ERR_KEY_REVOKED;
1.1 djm 1173: }
1174:
1.20 djm 1175: if (!sshkey_is_cert(key))
1.1 djm 1176: return 0;
1177:
1178: /* Check cert revocation */
1.20 djm 1179: if ((r = revoked_certs_for_ca_key(krl, key->cert->signature_key,
1180: &rc, 0)) != 0)
1181: return r;
1.1 djm 1182: if (rc == NULL)
1183: return 0; /* No entry for this CA */
1184:
1185: /* Check revocation by cert key ID */
1.14 tedu 1186: memset(&rki, 0, sizeof(rki));
1.1 djm 1187: rki.key_id = key->cert->key_id;
1188: erki = RB_FIND(revoked_key_id_tree, &rc->revoked_key_ids, &rki);
1189: if (erki != NULL) {
1.25 ! djm 1190: KRL_DBG(("%s: revoked by key ID", __func__));
1.20 djm 1191: return SSH_ERR_KEY_REVOKED;
1.1 djm 1192: }
1193:
1.8 djm 1194: /*
1195: * Legacy cert formats lack serial numbers. Zero serials numbers
1196: * are ignored (it's the default when the CA doesn't specify one).
1197: */
1.20 djm 1198: if (sshkey_cert_is_legacy(key) || key->cert->serial == 0)
1.1 djm 1199: return 0;
1200:
1.14 tedu 1201: memset(&rs, 0, sizeof(rs));
1.1 djm 1202: rs.lo = rs.hi = key->cert->serial;
1203: ers = RB_FIND(revoked_serial_tree, &rc->revoked_serials, &rs);
1204: if (ers != NULL) {
1.25 ! djm 1205: KRL_DBG(("%s: revoked serial %llu matched %llu:%llu", __func__,
1.1 djm 1206: key->cert->serial, ers->lo, ers->hi));
1.20 djm 1207: return SSH_ERR_KEY_REVOKED;
1.1 djm 1208: }
1209: KRL_DBG(("%s: %llu no match", __func__, key->cert->serial));
1210: return 0;
1211: }
1212:
1213: int
1.20 djm 1214: ssh_krl_check_key(struct ssh_krl *krl, const struct sshkey *key)
1.1 djm 1215: {
1216: int r;
1217:
1.25 ! djm 1218: KRL_DBG(("%s: checking key", __func__));
1.1 djm 1219: if ((r = is_key_revoked(krl, key)) != 0)
1220: return r;
1.20 djm 1221: if (sshkey_is_cert(key)) {
1.1 djm 1222: debug2("%s: checking CA key", __func__);
1223: if ((r = is_key_revoked(krl, key->cert->signature_key)) != 0)
1224: return r;
1225: }
1.25 ! djm 1226: KRL_DBG(("%s: key okay", __func__));
1.1 djm 1227: return 0;
1228: }
1229:
1230: int
1.20 djm 1231: ssh_krl_file_contains_key(const char *path, const struct sshkey *key)
1.1 djm 1232: {
1.20 djm 1233: struct sshbuf *krlbuf = NULL;
1234: struct ssh_krl *krl = NULL;
1235: int oerrno = 0, r, fd;
1.1 djm 1236:
1237: if (path == NULL)
1238: return 0;
1239:
1.20 djm 1240: if ((krlbuf = sshbuf_new()) == NULL)
1241: return SSH_ERR_ALLOC_FAIL;
1.1 djm 1242: if ((fd = open(path, O_RDONLY)) == -1) {
1.20 djm 1243: r = SSH_ERR_SYSTEM_ERROR;
1244: oerrno = errno;
1245: goto out;
1.1 djm 1246: }
1.22 djm 1247: if ((r = sshkey_load_file(fd, krlbuf)) != 0) {
1.20 djm 1248: oerrno = errno;
1249: goto out;
1.1 djm 1250: }
1.20 djm 1251: if ((r = ssh_krl_from_blob(krlbuf, &krl, NULL, 0)) != 0)
1252: goto out;
1253: debug2("%s: checking KRL %s", __func__, path);
1254: r = ssh_krl_check_key(krl, key);
1255: out:
1.1 djm 1256: close(fd);
1.20 djm 1257: sshbuf_free(krlbuf);
1.1 djm 1258: ssh_krl_free(krl);
1.20 djm 1259: if (r != 0)
1260: errno = oerrno;
1261: return r;
1.1 djm 1262: }
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