routerkeys.c 40 KB

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  1. /* Copyright (c) 2014-2017, The Tor Project, Inc. */
  2. /* See LICENSE for licensing information */
  3. /**
  4. * \file routerkeys.c
  5. *
  6. * \brief Functions and structures to handle generating and maintaining the
  7. * set of keypairs necessary to be an OR.
  8. *
  9. * The keys handled here now are the Ed25519 keys that Tor relays use to sign
  10. * descriptors, authenticate themselves on links, and identify one another
  11. * uniquely. Other keys are maintained in router.c and rendservice.c.
  12. *
  13. * (TODO: The keys in router.c should go here too.)
  14. */
  15. #include "or.h"
  16. #include "config.h"
  17. #include "router.h"
  18. #include "crypto_pwbox.h"
  19. #include "routerkeys.h"
  20. #include "torcert.h"
  21. #define ENC_KEY_HEADER "Boxed Ed25519 key"
  22. #define ENC_KEY_TAG "master"
  23. /* DOCDOC */
  24. static ssize_t
  25. do_getpass(const char *prompt, char *buf, size_t buflen,
  26. int twice, const or_options_t *options)
  27. {
  28. if (options->keygen_force_passphrase == FORCE_PASSPHRASE_OFF) {
  29. tor_assert(buflen);
  30. buf[0] = 0;
  31. return 0;
  32. }
  33. char *prompt2 = NULL;
  34. char *buf2 = NULL;
  35. int fd = -1;
  36. ssize_t length = -1;
  37. if (options->use_keygen_passphrase_fd) {
  38. twice = 0;
  39. fd = options->keygen_passphrase_fd;
  40. length = read_all(fd, buf, buflen-1, 0);
  41. if (length >= 0)
  42. buf[length] = 0;
  43. goto done_reading;
  44. }
  45. if (twice) {
  46. const char msg[] = "One more time:";
  47. size_t p2len = strlen(prompt) + 1;
  48. if (p2len < sizeof(msg))
  49. p2len = sizeof(msg);
  50. prompt2 = tor_malloc(p2len);
  51. memset(prompt2, ' ', p2len);
  52. memcpy(prompt2 + p2len - sizeof(msg), msg, sizeof(msg));
  53. buf2 = tor_malloc_zero(buflen);
  54. }
  55. while (1) {
  56. length = tor_getpass(prompt, buf, buflen);
  57. if (length < 0)
  58. goto done_reading;
  59. if (! twice)
  60. break;
  61. ssize_t length2 = tor_getpass(prompt2, buf2, buflen);
  62. if (length != length2 || tor_memneq(buf, buf2, length)) {
  63. fprintf(stderr, "That didn't match.\n");
  64. } else {
  65. break;
  66. }
  67. }
  68. done_reading:
  69. if (twice) {
  70. tor_free(prompt2);
  71. memwipe(buf2, 0, buflen);
  72. tor_free(buf2);
  73. }
  74. if (options->keygen_force_passphrase == FORCE_PASSPHRASE_ON && length == 0)
  75. return -1;
  76. return length;
  77. }
  78. /* DOCDOC */
  79. int
  80. read_encrypted_secret_key(ed25519_secret_key_t *out,
  81. const char *fname)
  82. {
  83. int r = -1;
  84. uint8_t *secret = NULL;
  85. size_t secret_len = 0;
  86. char pwbuf[256];
  87. uint8_t encrypted_key[256];
  88. char *tag = NULL;
  89. int saved_errno = 0;
  90. ssize_t encrypted_len = crypto_read_tagged_contents_from_file(fname,
  91. ENC_KEY_HEADER,
  92. &tag,
  93. encrypted_key,
  94. sizeof(encrypted_key));
  95. if (encrypted_len < 0) {
  96. saved_errno = errno;
  97. log_info(LD_OR, "%s is missing", fname);
  98. r = 0;
  99. goto done;
  100. }
  101. if (strcmp(tag, ENC_KEY_TAG)) {
  102. saved_errno = EINVAL;
  103. goto done;
  104. }
  105. while (1) {
  106. ssize_t pwlen =
  107. do_getpass("Enter passphrase for master key:", pwbuf, sizeof(pwbuf), 0,
  108. get_options());
  109. if (pwlen < 0) {
  110. saved_errno = EINVAL;
  111. goto done;
  112. }
  113. const int r_unbox = crypto_unpwbox(&secret, &secret_len,
  114. encrypted_key, encrypted_len,
  115. pwbuf, pwlen);
  116. if (r_unbox == UNPWBOX_CORRUPTED) {
  117. log_err(LD_OR, "%s is corrupted.", fname);
  118. saved_errno = EINVAL;
  119. goto done;
  120. } else if (r_unbox == UNPWBOX_OKAY) {
  121. break;
  122. }
  123. /* Otherwise, passphrase is bad, so try again till user does ctrl-c or gets
  124. * it right. */
  125. }
  126. if (secret_len != ED25519_SECKEY_LEN) {
  127. log_err(LD_OR, "%s is corrupted.", fname);
  128. saved_errno = EINVAL;
  129. goto done;
  130. }
  131. memcpy(out->seckey, secret, ED25519_SECKEY_LEN);
  132. r = 1;
  133. done:
  134. memwipe(encrypted_key, 0, sizeof(encrypted_key));
  135. memwipe(pwbuf, 0, sizeof(pwbuf));
  136. tor_free(tag);
  137. if (secret) {
  138. memwipe(secret, 0, secret_len);
  139. tor_free(secret);
  140. }
  141. if (saved_errno)
  142. errno = saved_errno;
  143. return r;
  144. }
  145. /* DOCDOC */
  146. int
  147. write_encrypted_secret_key(const ed25519_secret_key_t *key,
  148. const char *fname)
  149. {
  150. int r = -1;
  151. char pwbuf0[256];
  152. uint8_t *encrypted_key = NULL;
  153. size_t encrypted_len = 0;
  154. if (do_getpass("Enter new passphrase:", pwbuf0, sizeof(pwbuf0), 1,
  155. get_options()) < 0) {
  156. log_warn(LD_OR, "NO/failed passphrase");
  157. return -1;
  158. }
  159. if (strlen(pwbuf0) == 0) {
  160. if (get_options()->keygen_force_passphrase == FORCE_PASSPHRASE_ON)
  161. return -1;
  162. else
  163. return 0;
  164. }
  165. if (crypto_pwbox(&encrypted_key, &encrypted_len,
  166. key->seckey, sizeof(key->seckey),
  167. pwbuf0, strlen(pwbuf0), 0) < 0) {
  168. log_warn(LD_OR, "crypto_pwbox failed!?");
  169. goto done;
  170. }
  171. if (crypto_write_tagged_contents_to_file(fname,
  172. ENC_KEY_HEADER,
  173. ENC_KEY_TAG,
  174. encrypted_key, encrypted_len) < 0)
  175. goto done;
  176. r = 1;
  177. done:
  178. if (encrypted_key) {
  179. memwipe(encrypted_key, 0, encrypted_len);
  180. tor_free(encrypted_key);
  181. }
  182. memwipe(pwbuf0, 0, sizeof(pwbuf0));
  183. return r;
  184. }
  185. /* DOCDOC */
  186. static int
  187. write_secret_key(const ed25519_secret_key_t *key, int encrypted,
  188. const char *fname,
  189. const char *fname_tag,
  190. const char *encrypted_fname)
  191. {
  192. if (encrypted) {
  193. int r = write_encrypted_secret_key(key, encrypted_fname);
  194. if (r == 1) {
  195. /* Success! */
  196. /* Try to unlink the unencrypted key, if any existed before */
  197. if (strcmp(fname, encrypted_fname))
  198. unlink(fname);
  199. return r;
  200. } else if (r != 0) {
  201. /* Unrecoverable failure! */
  202. return r;
  203. }
  204. fprintf(stderr, "Not encrypting the secret key.\n");
  205. }
  206. return ed25519_seckey_write_to_file(key, fname, fname_tag);
  207. }
  208. /**
  209. * Read an ed25519 key and associated certificates from files beginning with
  210. * <b>fname</b>, with certificate type <b>cert_type</b>. On failure, return
  211. * NULL; on success return the keypair.
  212. *
  213. * If INIT_ED_KEY_CREATE is set in <b>flags</b>, then create the key (and
  214. * certificate if requested) if it doesn't exist, and save it to disk.
  215. *
  216. * If INIT_ED_KEY_NEEDCERT is set in <b>flags</b>, load/create a certificate
  217. * too and store it in *<b>cert_out</b>. Fail if the cert can't be
  218. * found/created. To create a certificate, <b>signing_key</b> must be set to
  219. * the key that should sign it; <b>now</b> to the current time, and
  220. * <b>lifetime</b> to the lifetime of the key.
  221. *
  222. * If INIT_ED_KEY_REPLACE is set in <b>flags</b>, then create and save new key
  223. * whether we can read the old one or not.
  224. *
  225. * If INIT_ED_KEY_EXTRA_STRONG is set in <b>flags</b>, set the extra_strong
  226. * flag when creating the secret key.
  227. *
  228. * If INIT_ED_KEY_INCLUDE_SIGNING_KEY_IN_CERT is set in <b>flags</b>, and
  229. * we create a new certificate, create it with the signing key embedded.
  230. *
  231. * If INIT_ED_KEY_SPLIT is set in <b>flags</b>, and we create a new key,
  232. * store the public key in a separate file from the secret key.
  233. *
  234. * If INIT_ED_KEY_MISSING_SECRET_OK is set in <b>flags</b>, and we find a
  235. * public key file but no secret key file, return successfully anyway.
  236. *
  237. * If INIT_ED_KEY_OMIT_SECRET is set in <b>flags</b>, do not try to load a
  238. * secret key unless no public key is found. Do not return a secret key. (but
  239. * create and save one if needed).
  240. *
  241. * If INIT_ED_KEY_NO_LOAD_SECRET is set in <b>flags</b>, don't try to load
  242. * a secret key, no matter what.
  243. *
  244. * If INIT_ED_KEY_TRY_ENCRYPTED is set, we look for an encrypted secret key
  245. * and consider encrypting any new secret key.
  246. *
  247. * If INIT_ED_KEY_NO_REPAIR is set, and there is any issue loading the keys
  248. * from disk _other than their absence_ (full or partial), we do not try to
  249. * replace them.
  250. *
  251. * If INIT_ED_KEY_SUGGEST_KEYGEN is set, have log messages about failures
  252. * refer to the --keygen option.
  253. *
  254. * If INIT_ED_KEY_EXPLICIT_FNAME is set, use the provided file name for the
  255. * secret key file, encrypted or not.
  256. */
  257. ed25519_keypair_t *
  258. ed_key_init_from_file(const char *fname, uint32_t flags,
  259. int severity,
  260. const ed25519_keypair_t *signing_key,
  261. time_t now,
  262. time_t lifetime,
  263. uint8_t cert_type,
  264. struct tor_cert_st **cert_out)
  265. {
  266. char *secret_fname = NULL;
  267. char *encrypted_secret_fname = NULL;
  268. char *public_fname = NULL;
  269. char *cert_fname = NULL;
  270. const char *loaded_secret_fname = NULL;
  271. int created_pk = 0, created_sk = 0, created_cert = 0;
  272. const int try_to_load = ! (flags & INIT_ED_KEY_REPLACE);
  273. const int encrypt_key = !! (flags & INIT_ED_KEY_TRY_ENCRYPTED);
  274. const int norepair = !! (flags & INIT_ED_KEY_NO_REPAIR);
  275. const int split = !! (flags & INIT_ED_KEY_SPLIT);
  276. const int omit_secret = !! (flags & INIT_ED_KEY_OMIT_SECRET);
  277. const int offline_secret = !! (flags & INIT_ED_KEY_OFFLINE_SECRET);
  278. const int explicit_fname = !! (flags & INIT_ED_KEY_EXPLICIT_FNAME);
  279. /* we don't support setting both of these flags at once. */
  280. tor_assert((flags & (INIT_ED_KEY_NO_REPAIR|INIT_ED_KEY_NEEDCERT)) !=
  281. (INIT_ED_KEY_NO_REPAIR|INIT_ED_KEY_NEEDCERT));
  282. char tag[8];
  283. tor_snprintf(tag, sizeof(tag), "type%d", (int)cert_type);
  284. tor_cert_t *cert = NULL;
  285. char *got_tag = NULL;
  286. ed25519_keypair_t *keypair = tor_malloc_zero(sizeof(ed25519_keypair_t));
  287. if (explicit_fname) {
  288. secret_fname = tor_strdup(fname);
  289. encrypted_secret_fname = tor_strdup(fname);
  290. } else {
  291. tor_asprintf(&secret_fname, "%s_secret_key", fname);
  292. tor_asprintf(&encrypted_secret_fname, "%s_secret_key_encrypted", fname);
  293. }
  294. tor_asprintf(&public_fname, "%s_public_key", fname);
  295. tor_asprintf(&cert_fname, "%s_cert", fname);
  296. /* Try to read the secret key. */
  297. int have_secret = 0;
  298. int load_secret = try_to_load &&
  299. !offline_secret &&
  300. (!omit_secret || file_status(public_fname)==FN_NOENT);
  301. if (load_secret) {
  302. int rv = ed25519_seckey_read_from_file(&keypair->seckey,
  303. &got_tag, secret_fname);
  304. if (rv == 0) {
  305. have_secret = 1;
  306. loaded_secret_fname = secret_fname;
  307. tor_assert(got_tag);
  308. } else {
  309. if (errno != ENOENT && norepair) {
  310. tor_log(severity, LD_OR, "Unable to read %s: %s", secret_fname,
  311. strerror(errno));
  312. goto err;
  313. }
  314. }
  315. }
  316. /* Should we try for an encrypted key? */
  317. int have_encrypted_secret_file = 0;
  318. if (!have_secret && try_to_load && encrypt_key) {
  319. int r = read_encrypted_secret_key(&keypair->seckey,
  320. encrypted_secret_fname);
  321. if (r > 0) {
  322. have_secret = 1;
  323. have_encrypted_secret_file = 1;
  324. tor_free(got_tag); /* convince coverity we aren't leaking */
  325. got_tag = tor_strdup(tag);
  326. loaded_secret_fname = encrypted_secret_fname;
  327. } else if (errno != ENOENT && norepair) {
  328. tor_log(severity, LD_OR, "Unable to read %s: %s",
  329. encrypted_secret_fname, strerror(errno));
  330. goto err;
  331. }
  332. } else {
  333. if (try_to_load) {
  334. /* Check if it's there anyway, so we don't replace it. */
  335. if (file_status(encrypted_secret_fname) != FN_NOENT)
  336. have_encrypted_secret_file = 1;
  337. }
  338. }
  339. if (have_secret) {
  340. if (strcmp(got_tag, tag)) {
  341. tor_log(severity, LD_OR, "%s has wrong tag", loaded_secret_fname);
  342. goto err;
  343. }
  344. /* Derive the public key */
  345. if (ed25519_public_key_generate(&keypair->pubkey, &keypair->seckey)<0) {
  346. tor_log(severity, LD_OR, "%s can't produce a public key",
  347. loaded_secret_fname);
  348. goto err;
  349. }
  350. }
  351. /* If we do split keys here, try to read the pubkey. */
  352. int found_public = 0;
  353. if (try_to_load && (!have_secret || split)) {
  354. ed25519_public_key_t pubkey_tmp;
  355. tor_free(got_tag);
  356. found_public = ed25519_pubkey_read_from_file(&pubkey_tmp,
  357. &got_tag, public_fname) == 0;
  358. if (!found_public && errno != ENOENT && norepair) {
  359. tor_log(severity, LD_OR, "Unable to read %s: %s", public_fname,
  360. strerror(errno));
  361. goto err;
  362. }
  363. if (found_public && strcmp(got_tag, tag)) {
  364. tor_log(severity, LD_OR, "%s has wrong tag", public_fname);
  365. goto err;
  366. }
  367. if (found_public) {
  368. if (have_secret) {
  369. /* If we have a secret key and we're reloading the public key,
  370. * the key must match! */
  371. if (! ed25519_pubkey_eq(&keypair->pubkey, &pubkey_tmp)) {
  372. tor_log(severity, LD_OR, "%s does not match %s! If you are trying "
  373. "to restore from backup, make sure you didn't mix up the "
  374. "key files. If you are absolutely sure that %s is the right "
  375. "key for this relay, delete %s or move it out of the way.",
  376. public_fname, loaded_secret_fname,
  377. loaded_secret_fname, public_fname);
  378. goto err;
  379. }
  380. } else {
  381. /* We only have the public key; better use that. */
  382. tor_assert(split);
  383. memcpy(&keypair->pubkey, &pubkey_tmp, sizeof(pubkey_tmp));
  384. }
  385. } else {
  386. /* We have no public key file, but we do have a secret key, make the
  387. * public key file! */
  388. if (have_secret) {
  389. if (ed25519_pubkey_write_to_file(&keypair->pubkey, public_fname, tag)
  390. < 0) {
  391. tor_log(severity, LD_OR, "Couldn't repair %s", public_fname);
  392. goto err;
  393. } else {
  394. tor_log(LOG_NOTICE, LD_OR,
  395. "Found secret key but not %s. Regenerating.",
  396. public_fname);
  397. }
  398. }
  399. }
  400. }
  401. /* If the secret key is absent and it's not allowed to be, fail. */
  402. if (!have_secret && found_public &&
  403. !(flags & INIT_ED_KEY_MISSING_SECRET_OK)) {
  404. if (have_encrypted_secret_file) {
  405. tor_log(severity, LD_OR, "We needed to load a secret key from %s, "
  406. "but it was encrypted. Try 'tor --keygen' instead, so you "
  407. "can enter the passphrase.",
  408. secret_fname);
  409. } else if (offline_secret) {
  410. tor_log(severity, LD_OR, "We wanted to load a secret key from %s, "
  411. "but you're keeping it offline. (OfflineMasterKey is set.)",
  412. secret_fname);
  413. } else {
  414. tor_log(severity, LD_OR, "We needed to load a secret key from %s, "
  415. "but couldn't find it. %s", secret_fname,
  416. (flags & INIT_ED_KEY_SUGGEST_KEYGEN) ?
  417. "If you're keeping your master secret key offline, you will "
  418. "need to run 'tor --keygen' to generate new signing keys." :
  419. "Did you forget to copy it over when you copied the rest of the "
  420. "signing key material?");
  421. }
  422. goto err;
  423. }
  424. /* If it's absent, and we're not supposed to make a new keypair, fail. */
  425. if (!have_secret && !found_public && !(flags & INIT_ED_KEY_CREATE)) {
  426. if (split) {
  427. tor_log(severity, LD_OR, "No key found in %s or %s.",
  428. secret_fname, public_fname);
  429. } else {
  430. tor_log(severity, LD_OR, "No key found in %s.", secret_fname);
  431. }
  432. goto err;
  433. }
  434. /* If the secret key is absent, but the encrypted key would be present,
  435. * that's an error */
  436. if (!have_secret && !found_public && have_encrypted_secret_file) {
  437. tor_assert(!encrypt_key);
  438. tor_log(severity, LD_OR, "Found an encrypted secret key, "
  439. "but not public key file %s!", public_fname);
  440. goto err;
  441. }
  442. /* if it's absent, make a new keypair... */
  443. if (!have_secret && !found_public) {
  444. tor_free(keypair);
  445. keypair = ed_key_new(signing_key, flags, now, lifetime,
  446. cert_type, &cert);
  447. if (!keypair) {
  448. tor_log(severity, LD_OR, "Couldn't create keypair");
  449. goto err;
  450. }
  451. created_pk = created_sk = created_cert = 1;
  452. }
  453. /* Write it to disk if we're supposed to do with a new passphrase, or if
  454. * we just created it. */
  455. if (created_sk || (have_secret && get_options()->change_key_passphrase)) {
  456. if (write_secret_key(&keypair->seckey,
  457. encrypt_key,
  458. secret_fname, tag, encrypted_secret_fname) < 0
  459. ||
  460. (split &&
  461. ed25519_pubkey_write_to_file(&keypair->pubkey, public_fname, tag) < 0)
  462. ||
  463. (cert &&
  464. crypto_write_tagged_contents_to_file(cert_fname, "ed25519v1-cert",
  465. tag, cert->encoded, cert->encoded_len) < 0)) {
  466. tor_log(severity, LD_OR, "Couldn't write keys or cert to file.");
  467. goto err;
  468. }
  469. goto done;
  470. }
  471. /* If we're not supposed to get a cert, we're done. */
  472. if (! (flags & INIT_ED_KEY_NEEDCERT))
  473. goto done;
  474. /* Read a cert. */
  475. tor_free(got_tag);
  476. uint8_t certbuf[256];
  477. ssize_t cert_body_len = crypto_read_tagged_contents_from_file(
  478. cert_fname, "ed25519v1-cert",
  479. &got_tag, certbuf, sizeof(certbuf));
  480. if (cert_body_len >= 0 && !strcmp(got_tag, tag))
  481. cert = tor_cert_parse(certbuf, cert_body_len);
  482. /* If we got it, check it to the extent we can. */
  483. int bad_cert = 0;
  484. if (! cert) {
  485. tor_log(severity, LD_OR, "Cert was unparseable");
  486. bad_cert = 1;
  487. } else if (!tor_memeq(cert->signed_key.pubkey, keypair->pubkey.pubkey,
  488. ED25519_PUBKEY_LEN)) {
  489. tor_log(severity, LD_OR, "Cert was for wrong key");
  490. bad_cert = 1;
  491. } else if (signing_key &&
  492. tor_cert_checksig(cert, &signing_key->pubkey, now) < 0) {
  493. tor_log(severity, LD_OR, "Can't check certificate");
  494. bad_cert = 1;
  495. } else if (cert->cert_expired) {
  496. tor_log(severity, LD_OR, "Certificate is expired");
  497. bad_cert = 1;
  498. } else if (signing_key && cert->signing_key_included &&
  499. ! ed25519_pubkey_eq(&signing_key->pubkey, &cert->signing_key)) {
  500. tor_log(severity, LD_OR, "Certificate signed by unexpectd key!");
  501. bad_cert = 1;
  502. }
  503. if (bad_cert) {
  504. tor_cert_free(cert);
  505. cert = NULL;
  506. }
  507. /* If we got a cert, we're done. */
  508. if (cert)
  509. goto done;
  510. /* If we didn't get a cert, and we're not supposed to make one, fail. */
  511. if (!signing_key || !(flags & INIT_ED_KEY_CREATE)) {
  512. tor_log(severity, LD_OR, "Without signing key, can't create certificate");
  513. goto err;
  514. }
  515. /* We have keys but not a certificate, so make one. */
  516. uint32_t cert_flags = 0;
  517. if (flags & INIT_ED_KEY_INCLUDE_SIGNING_KEY_IN_CERT)
  518. cert_flags |= CERT_FLAG_INCLUDE_SIGNING_KEY;
  519. cert = tor_cert_create(signing_key, cert_type,
  520. &keypair->pubkey,
  521. now, lifetime,
  522. cert_flags);
  523. if (! cert) {
  524. tor_log(severity, LD_OR, "Couldn't create certificate");
  525. goto err;
  526. }
  527. /* Write it to disk. */
  528. created_cert = 1;
  529. if (crypto_write_tagged_contents_to_file(cert_fname, "ed25519v1-cert",
  530. tag, cert->encoded, cert->encoded_len) < 0) {
  531. tor_log(severity, LD_OR, "Couldn't write cert to disk.");
  532. goto err;
  533. }
  534. done:
  535. if (cert_out)
  536. *cert_out = cert;
  537. else
  538. tor_cert_free(cert);
  539. goto cleanup;
  540. err:
  541. if (keypair)
  542. memwipe(keypair, 0, sizeof(*keypair));
  543. tor_free(keypair);
  544. tor_cert_free(cert);
  545. if (cert_out)
  546. *cert_out = NULL;
  547. if (created_sk)
  548. unlink(secret_fname);
  549. if (created_pk)
  550. unlink(public_fname);
  551. if (created_cert)
  552. unlink(cert_fname);
  553. cleanup:
  554. tor_free(encrypted_secret_fname);
  555. tor_free(secret_fname);
  556. tor_free(public_fname);
  557. tor_free(cert_fname);
  558. tor_free(got_tag);
  559. return keypair;
  560. }
  561. /**
  562. * Create a new signing key and (optionally) certficiate; do not read or write
  563. * from disk. See ed_key_init_from_file() for more information.
  564. */
  565. ed25519_keypair_t *
  566. ed_key_new(const ed25519_keypair_t *signing_key,
  567. uint32_t flags,
  568. time_t now,
  569. time_t lifetime,
  570. uint8_t cert_type,
  571. struct tor_cert_st **cert_out)
  572. {
  573. if (cert_out)
  574. *cert_out = NULL;
  575. const int extra_strong = !! (flags & INIT_ED_KEY_EXTRA_STRONG);
  576. ed25519_keypair_t *keypair = tor_malloc_zero(sizeof(ed25519_keypair_t));
  577. if (ed25519_keypair_generate(keypair, extra_strong) < 0)
  578. goto err;
  579. if (! (flags & INIT_ED_KEY_NEEDCERT))
  580. return keypair;
  581. tor_assert(signing_key);
  582. tor_assert(cert_out);
  583. uint32_t cert_flags = 0;
  584. if (flags & INIT_ED_KEY_INCLUDE_SIGNING_KEY_IN_CERT)
  585. cert_flags |= CERT_FLAG_INCLUDE_SIGNING_KEY;
  586. tor_cert_t *cert = tor_cert_create(signing_key, cert_type,
  587. &keypair->pubkey,
  588. now, lifetime,
  589. cert_flags);
  590. if (! cert)
  591. goto err;
  592. *cert_out = cert;
  593. return keypair;
  594. err:
  595. tor_free(keypair);
  596. return NULL;
  597. }
  598. static ed25519_keypair_t *master_identity_key = NULL;
  599. static ed25519_keypair_t *master_signing_key = NULL;
  600. static ed25519_keypair_t *current_auth_key = NULL;
  601. static tor_cert_t *signing_key_cert = NULL;
  602. static tor_cert_t *link_cert_cert = NULL;
  603. static tor_cert_t *auth_key_cert = NULL;
  604. static uint8_t *rsa_ed_crosscert = NULL;
  605. static size_t rsa_ed_crosscert_len = 0;
  606. /**
  607. * Running as a server: load, reload, or refresh our ed25519 keys and
  608. * certificates, creating and saving new ones as needed.
  609. */
  610. int
  611. load_ed_keys(const or_options_t *options, time_t now)
  612. {
  613. ed25519_keypair_t *id = NULL;
  614. ed25519_keypair_t *sign = NULL;
  615. ed25519_keypair_t *auth = NULL;
  616. const ed25519_keypair_t *sign_signing_key_with_id = NULL;
  617. const ed25519_keypair_t *use_signing = NULL;
  618. const tor_cert_t *check_signing_cert = NULL;
  619. tor_cert_t *sign_cert = NULL;
  620. tor_cert_t *auth_cert = NULL;
  621. #define FAIL(msg) do { \
  622. log_warn(LD_OR, (msg)); \
  623. goto err; \
  624. } while (0)
  625. #define SET_KEY(key, newval) do { \
  626. if ((key) != (newval)) \
  627. ed25519_keypair_free(key); \
  628. key = (newval); \
  629. } while (0)
  630. #define SET_CERT(cert, newval) do { \
  631. if ((cert) != (newval)) \
  632. tor_cert_free(cert); \
  633. cert = (newval); \
  634. } while (0)
  635. #define EXPIRES_SOON(cert, interval) \
  636. (!(cert) || (cert)->valid_until < now + (interval))
  637. /* XXXX support encrypted identity keys fully */
  638. /* First try to get the signing key to see how it is. */
  639. {
  640. char *fname =
  641. options_get_datadir_fname2(options, "keys", "ed25519_signing");
  642. sign = ed_key_init_from_file(
  643. fname,
  644. INIT_ED_KEY_NEEDCERT|
  645. INIT_ED_KEY_INCLUDE_SIGNING_KEY_IN_CERT,
  646. LOG_INFO,
  647. NULL, 0, 0, CERT_TYPE_ID_SIGNING, &sign_cert);
  648. tor_free(fname);
  649. check_signing_cert = sign_cert;
  650. use_signing = sign;
  651. }
  652. if (!use_signing && master_signing_key) {
  653. check_signing_cert = signing_key_cert;
  654. use_signing = master_signing_key;
  655. }
  656. const int offline_master =
  657. options->OfflineMasterKey && options->command != CMD_KEYGEN;
  658. const int need_new_signing_key =
  659. NULL == use_signing ||
  660. EXPIRES_SOON(check_signing_cert, 0) ||
  661. (options->command == CMD_KEYGEN && ! options->change_key_passphrase);
  662. const int want_new_signing_key =
  663. need_new_signing_key ||
  664. EXPIRES_SOON(check_signing_cert, options->TestingSigningKeySlop);
  665. /* We can only create a master key if we haven't been told that the
  666. * master key will always be offline. Also, if we have a signing key,
  667. * then we shouldn't make a new master ID key. */
  668. const int can_make_master_id_key = !offline_master &&
  669. NULL == use_signing;
  670. if (need_new_signing_key) {
  671. log_notice(LD_OR, "It looks like I need to generate and sign a new "
  672. "medium-term signing key, because %s. To do that, I "
  673. "need to load%s the permanent master identity key. "
  674. "If the master identity key was not moved or encrypted "
  675. "with a passphrase, this will be done automatically and "
  676. "no further action is required. Otherwise, provide the "
  677. "necessary data using 'tor --keygen' to do it manually.",
  678. (NULL == use_signing) ? "I don't have one" :
  679. EXPIRES_SOON(check_signing_cert, 0) ? "the one I have is expired" :
  680. "you asked me to make one with --keygen",
  681. can_make_master_id_key ? " (or create)" : "");
  682. } else if (want_new_signing_key && !offline_master) {
  683. log_notice(LD_OR, "It looks like I should try to generate and sign a "
  684. "new medium-term signing key, because the one I have is "
  685. "going to expire soon. To do that, I'm going to have to "
  686. "try to load the permanent master identity key. "
  687. "If the master identity key was not moved or encrypted "
  688. "with a passphrase, this will be done automatically and "
  689. "no further action is required. Otherwise, provide the "
  690. "necessary data using 'tor --keygen' to do it manually.");
  691. } else if (want_new_signing_key) {
  692. log_notice(LD_OR, "It looks like I should try to generate and sign a "
  693. "new medium-term signing key, because the one I have is "
  694. "going to expire soon. But OfflineMasterKey is set, so I "
  695. "won't try to load a permanent master identity key. You "
  696. "will need to use 'tor --keygen' to make a new signing "
  697. "key and certificate.");
  698. }
  699. {
  700. uint32_t flags =
  701. (INIT_ED_KEY_SPLIT|
  702. INIT_ED_KEY_EXTRA_STRONG|INIT_ED_KEY_NO_REPAIR);
  703. if (can_make_master_id_key)
  704. flags |= INIT_ED_KEY_CREATE;
  705. if (! need_new_signing_key)
  706. flags |= INIT_ED_KEY_MISSING_SECRET_OK;
  707. if (! want_new_signing_key || offline_master)
  708. flags |= INIT_ED_KEY_OMIT_SECRET;
  709. if (offline_master)
  710. flags |= INIT_ED_KEY_OFFLINE_SECRET;
  711. if (options->command == CMD_KEYGEN)
  712. flags |= INIT_ED_KEY_TRY_ENCRYPTED;
  713. /* Check/Create the key directory */
  714. cpd_check_t cpd_opts = CPD_CREATE;
  715. if (options->DataDirectoryGroupReadable)
  716. cpd_opts |= CPD_GROUP_READ;
  717. if (check_private_dir(options->DataDirectory, cpd_opts, options->User)) {
  718. log_err(LD_OR, "Can't create/check datadirectory %s",
  719. options->DataDirectory);
  720. goto err;
  721. }
  722. char *fname = get_datadir_fname("keys");
  723. if (check_private_dir(fname, CPD_CREATE, options->User) < 0) {
  724. log_err(LD_OR, "Problem creating/checking key directory %s", fname);
  725. tor_free(fname);
  726. goto err;
  727. }
  728. tor_free(fname);
  729. if (options->master_key_fname) {
  730. fname = tor_strdup(options->master_key_fname);
  731. flags |= INIT_ED_KEY_EXPLICIT_FNAME;
  732. } else {
  733. fname = options_get_datadir_fname2(options, "keys", "ed25519_master_id");
  734. }
  735. id = ed_key_init_from_file(
  736. fname,
  737. flags,
  738. LOG_WARN, NULL, 0, 0, 0, NULL);
  739. tor_free(fname);
  740. if (!id) {
  741. if (need_new_signing_key) {
  742. if (offline_master)
  743. FAIL("Can't load master identity key; OfflineMasterKey is set.");
  744. else
  745. FAIL("Missing identity key");
  746. } else {
  747. log_warn(LD_OR, "Master public key was absent; inferring from "
  748. "public key in signing certificate and saving to disk.");
  749. tor_assert(check_signing_cert);
  750. id = tor_malloc_zero(sizeof(*id));
  751. memcpy(&id->pubkey, &check_signing_cert->signing_key,
  752. sizeof(ed25519_public_key_t));
  753. fname = options_get_datadir_fname2(options, "keys",
  754. "ed25519_master_id_public_key");
  755. if (ed25519_pubkey_write_to_file(&id->pubkey, fname, "type0") < 0) {
  756. log_warn(LD_OR, "Error while attempting to write master public key "
  757. "to disk");
  758. tor_free(fname);
  759. goto err;
  760. }
  761. tor_free(fname);
  762. }
  763. }
  764. if (tor_mem_is_zero((char*)id->seckey.seckey, sizeof(id->seckey)))
  765. sign_signing_key_with_id = NULL;
  766. else
  767. sign_signing_key_with_id = id;
  768. }
  769. if (master_identity_key &&
  770. !ed25519_pubkey_eq(&id->pubkey, &master_identity_key->pubkey)) {
  771. FAIL("Identity key on disk does not match key we loaded earlier!");
  772. }
  773. if (need_new_signing_key && NULL == sign_signing_key_with_id)
  774. FAIL("Can't load master key make a new signing key.");
  775. if (sign_cert) {
  776. if (! sign_cert->signing_key_included)
  777. FAIL("Loaded a signing cert with no key included!");
  778. if (! ed25519_pubkey_eq(&sign_cert->signing_key, &id->pubkey))
  779. FAIL("The signing cert we have was not signed with the master key "
  780. "we loaded!");
  781. if (tor_cert_checksig(sign_cert, &id->pubkey, 0) < 0)
  782. FAIL("The signing cert we loaded was not signed correctly!");
  783. }
  784. if (want_new_signing_key && sign_signing_key_with_id) {
  785. uint32_t flags = (INIT_ED_KEY_CREATE|
  786. INIT_ED_KEY_REPLACE|
  787. INIT_ED_KEY_EXTRA_STRONG|
  788. INIT_ED_KEY_NEEDCERT|
  789. INIT_ED_KEY_INCLUDE_SIGNING_KEY_IN_CERT);
  790. char *fname =
  791. options_get_datadir_fname2(options, "keys", "ed25519_signing");
  792. ed25519_keypair_free(sign);
  793. tor_cert_free(sign_cert);
  794. sign = ed_key_init_from_file(fname,
  795. flags, LOG_WARN,
  796. sign_signing_key_with_id, now,
  797. options->SigningKeyLifetime,
  798. CERT_TYPE_ID_SIGNING, &sign_cert);
  799. tor_free(fname);
  800. if (!sign)
  801. FAIL("Missing signing key");
  802. use_signing = sign;
  803. tor_assert(sign_cert->signing_key_included);
  804. tor_assert(ed25519_pubkey_eq(&sign_cert->signing_key, &id->pubkey));
  805. tor_assert(ed25519_pubkey_eq(&sign_cert->signed_key, &sign->pubkey));
  806. } else if (want_new_signing_key) {
  807. static ratelim_t missing_master = RATELIM_INIT(3600);
  808. log_fn_ratelim(&missing_master, LOG_WARN, LD_OR,
  809. "Signing key will expire soon, but I can't load the "
  810. "master key to sign a new one!");
  811. }
  812. tor_assert(use_signing);
  813. /* At this point we no longer need our secret identity key. So wipe
  814. * it, if we loaded it in the first place. */
  815. memwipe(id->seckey.seckey, 0, sizeof(id->seckey));
  816. if (options->command == CMD_KEYGEN)
  817. goto end;
  818. if (!rsa_ed_crosscert && server_mode(options)) {
  819. uint8_t *crosscert;
  820. ssize_t crosscert_len = tor_make_rsa_ed25519_crosscert(&id->pubkey,
  821. get_server_identity_key(),
  822. now+10*365*86400,/*XXXX*/
  823. &crosscert);
  824. rsa_ed_crosscert_len = crosscert_len;
  825. rsa_ed_crosscert = crosscert;
  826. }
  827. if (!current_auth_key ||
  828. EXPIRES_SOON(auth_key_cert, options->TestingAuthKeySlop)) {
  829. auth = ed_key_new(use_signing, INIT_ED_KEY_NEEDCERT,
  830. now,
  831. options->TestingAuthKeyLifetime,
  832. CERT_TYPE_SIGNING_AUTH, &auth_cert);
  833. if (!auth)
  834. FAIL("Can't create auth key");
  835. }
  836. /* We've generated or loaded everything. Put them in memory. */
  837. end:
  838. if (! master_identity_key) {
  839. SET_KEY(master_identity_key, id);
  840. } else {
  841. tor_free(id);
  842. }
  843. if (sign) {
  844. SET_KEY(master_signing_key, sign);
  845. SET_CERT(signing_key_cert, sign_cert);
  846. }
  847. if (auth) {
  848. SET_KEY(current_auth_key, auth);
  849. SET_CERT(auth_key_cert, auth_cert);
  850. }
  851. return 0;
  852. err:
  853. ed25519_keypair_free(id);
  854. ed25519_keypair_free(sign);
  855. ed25519_keypair_free(auth);
  856. tor_cert_free(sign_cert);
  857. tor_cert_free(auth_cert);
  858. return -1;
  859. }
  860. /**
  861. * Retrieve our currently-in-use Ed25519 link certificate and id certificate,
  862. * and, if they would expire soon (based on the time <b>now</b>, generate new
  863. * certificates (without embedding the public part of the signing key inside).
  864. *
  865. * The signed_key from the expiring certificate will be used to sign the new
  866. * key within newly generated X509 certificate.
  867. *
  868. * Returns -1 upon error. Otherwise, returns 0 upon success (either when the
  869. * current certificate is still valid, or when a new certificate was
  870. * successfully generated).
  871. */
  872. int
  873. generate_ed_link_cert(const or_options_t *options, time_t now)
  874. {
  875. const tor_x509_cert_t *link_ = NULL, *id = NULL;
  876. tor_cert_t *link_cert = NULL;
  877. if (tor_tls_get_my_certs(1, &link_, &id) < 0 || link_ == NULL) {
  878. log_warn(LD_OR, "Can't get my x509 link cert.");
  879. return -1;
  880. }
  881. const common_digests_t *digests = tor_x509_cert_get_cert_digests(link_);
  882. if (link_cert_cert &&
  883. ! EXPIRES_SOON(link_cert_cert, options->TestingLinkKeySlop) &&
  884. fast_memeq(digests->d[DIGEST_SHA256], link_cert_cert->signed_key.pubkey,
  885. DIGEST256_LEN)) {
  886. return 0;
  887. }
  888. ed25519_public_key_t dummy_key;
  889. memcpy(dummy_key.pubkey, digests->d[DIGEST_SHA256], DIGEST256_LEN);
  890. link_cert = tor_cert_create(get_master_signing_keypair(),
  891. CERT_TYPE_SIGNING_LINK,
  892. &dummy_key,
  893. now,
  894. options->TestingLinkCertLifetime, 0);
  895. if (link_cert) {
  896. SET_CERT(link_cert_cert, link_cert);
  897. }
  898. return 0;
  899. }
  900. #undef FAIL
  901. #undef SET_KEY
  902. #undef SET_CERT
  903. /**
  904. * Return 1 if any of the following are true:
  905. *
  906. * - if one of our Ed25519 signing, auth, or link certificates would expire
  907. * soon w.r.t. the time <b>now</b>,
  908. * - if we do not currently have a link certificate, or
  909. * - if our cached Ed25519 link certificate is not same as the one we're
  910. * currently using.
  911. *
  912. * Otherwise, returns 0.
  913. */
  914. int
  915. should_make_new_ed_keys(const or_options_t *options, const time_t now)
  916. {
  917. if (!master_identity_key ||
  918. !master_signing_key ||
  919. !current_auth_key ||
  920. !link_cert_cert ||
  921. EXPIRES_SOON(signing_key_cert, options->TestingSigningKeySlop) ||
  922. EXPIRES_SOON(auth_key_cert, options->TestingAuthKeySlop) ||
  923. EXPIRES_SOON(link_cert_cert, options->TestingLinkKeySlop))
  924. return 1;
  925. const tor_x509_cert_t *link_ = NULL, *id = NULL;
  926. if (tor_tls_get_my_certs(1, &link_, &id) < 0 || link_ == NULL)
  927. return 1;
  928. const common_digests_t *digests = tor_x509_cert_get_cert_digests(link_);
  929. if (!fast_memeq(digests->d[DIGEST_SHA256],
  930. link_cert_cert->signed_key.pubkey,
  931. DIGEST256_LEN)) {
  932. return 1;
  933. }
  934. return 0;
  935. }
  936. #undef EXPIRES_SOON
  937. #ifdef TOR_UNIT_TESTS
  938. /* Helper for unit tests: populate the ed25519 keys without saving or
  939. * loading */
  940. void
  941. init_mock_ed_keys(const crypto_pk_t *rsa_identity_key)
  942. {
  943. routerkeys_free_all();
  944. #define MAKEKEY(k) \
  945. k = tor_malloc_zero(sizeof(*k)); \
  946. if (ed25519_keypair_generate(k, 0) < 0) { \
  947. log_warn(LD_BUG, "Couldn't make a keypair"); \
  948. goto err; \
  949. }
  950. MAKEKEY(master_identity_key);
  951. MAKEKEY(master_signing_key);
  952. MAKEKEY(current_auth_key);
  953. #define MAKECERT(cert, signing, signed_, type, flags) \
  954. cert = tor_cert_create(signing, \
  955. type, \
  956. &signed_->pubkey, \
  957. time(NULL), 86400, \
  958. flags); \
  959. if (!cert) { \
  960. log_warn(LD_BUG, "Couldn't make a %s certificate!", #cert); \
  961. goto err; \
  962. }
  963. MAKECERT(signing_key_cert,
  964. master_identity_key, master_signing_key, CERT_TYPE_ID_SIGNING,
  965. CERT_FLAG_INCLUDE_SIGNING_KEY);
  966. MAKECERT(auth_key_cert,
  967. master_signing_key, current_auth_key, CERT_TYPE_SIGNING_AUTH, 0);
  968. if (generate_ed_link_cert(get_options(), time(NULL)) < 0) {
  969. log_warn(LD_BUG, "Couldn't make link certificate");
  970. goto err;
  971. }
  972. rsa_ed_crosscert_len = tor_make_rsa_ed25519_crosscert(
  973. &master_identity_key->pubkey,
  974. rsa_identity_key,
  975. time(NULL)+86400,
  976. &rsa_ed_crosscert);
  977. return;
  978. err:
  979. routerkeys_free_all();
  980. tor_assert_nonfatal_unreached();
  981. }
  982. #undef MAKEKEY
  983. #undef MAKECERT
  984. #endif
  985. const ed25519_public_key_t *
  986. get_master_identity_key(void)
  987. {
  988. if (!master_identity_key)
  989. return NULL;
  990. return &master_identity_key->pubkey;
  991. }
  992. /** Return true iff <b>id</b> is our Ed25519 master identity key. */
  993. int
  994. router_ed25519_id_is_me(const ed25519_public_key_t *id)
  995. {
  996. return id && master_identity_key &&
  997. ed25519_pubkey_eq(id, &master_identity_key->pubkey);
  998. }
  999. #ifdef TOR_UNIT_TESTS
  1000. /* only exists for the unit tests, since otherwise the identity key
  1001. * should be used to sign nothing but the signing key. */
  1002. const ed25519_keypair_t *
  1003. get_master_identity_keypair(void)
  1004. {
  1005. return master_identity_key;
  1006. }
  1007. #endif
  1008. const ed25519_keypair_t *
  1009. get_master_signing_keypair(void)
  1010. {
  1011. return master_signing_key;
  1012. }
  1013. const struct tor_cert_st *
  1014. get_master_signing_key_cert(void)
  1015. {
  1016. return signing_key_cert;
  1017. }
  1018. const ed25519_keypair_t *
  1019. get_current_auth_keypair(void)
  1020. {
  1021. return current_auth_key;
  1022. }
  1023. const tor_cert_t *
  1024. get_current_link_cert_cert(void)
  1025. {
  1026. return link_cert_cert;
  1027. }
  1028. const tor_cert_t *
  1029. get_current_auth_key_cert(void)
  1030. {
  1031. return auth_key_cert;
  1032. }
  1033. void
  1034. get_master_rsa_crosscert(const uint8_t **cert_out,
  1035. size_t *size_out)
  1036. {
  1037. *cert_out = rsa_ed_crosscert;
  1038. *size_out = rsa_ed_crosscert_len;
  1039. }
  1040. /** Construct cross-certification for the master identity key with
  1041. * the ntor onion key. Store the sign of the corresponding ed25519 public key
  1042. * in *<b>sign_out</b>. */
  1043. tor_cert_t *
  1044. make_ntor_onion_key_crosscert(const curve25519_keypair_t *onion_key,
  1045. const ed25519_public_key_t *master_id_key, time_t now, time_t lifetime,
  1046. int *sign_out)
  1047. {
  1048. tor_cert_t *cert = NULL;
  1049. ed25519_keypair_t ed_onion_key;
  1050. if (ed25519_keypair_from_curve25519_keypair(&ed_onion_key, sign_out,
  1051. onion_key) < 0)
  1052. goto end;
  1053. cert = tor_cert_create(&ed_onion_key, CERT_TYPE_ONION_ID, master_id_key,
  1054. now, lifetime, 0);
  1055. end:
  1056. memwipe(&ed_onion_key, 0, sizeof(ed_onion_key));
  1057. return cert;
  1058. }
  1059. /** Construct and return an RSA signature for the TAP onion key to
  1060. * cross-certify the RSA and Ed25519 identity keys. Set <b>len_out</b> to its
  1061. * length. */
  1062. uint8_t *
  1063. make_tap_onion_key_crosscert(const crypto_pk_t *onion_key,
  1064. const ed25519_public_key_t *master_id_key,
  1065. const crypto_pk_t *rsa_id_key,
  1066. int *len_out)
  1067. {
  1068. uint8_t signature[PK_BYTES];
  1069. uint8_t signed_data[DIGEST_LEN + ED25519_PUBKEY_LEN];
  1070. *len_out = 0;
  1071. crypto_pk_get_digest(rsa_id_key, (char*)signed_data);
  1072. memcpy(signed_data + DIGEST_LEN, master_id_key->pubkey, ED25519_PUBKEY_LEN);
  1073. int r = crypto_pk_private_sign(onion_key,
  1074. (char*)signature, sizeof(signature),
  1075. (const char*)signed_data, sizeof(signed_data));
  1076. if (r < 0)
  1077. return NULL;
  1078. *len_out = r;
  1079. return tor_memdup(signature, r);
  1080. }
  1081. /** Check whether an RSA-TAP cross-certification is correct. Return 0 if it
  1082. * is, -1 if it isn't. */
  1083. MOCK_IMPL(int,
  1084. check_tap_onion_key_crosscert,(const uint8_t *crosscert,
  1085. int crosscert_len,
  1086. const crypto_pk_t *onion_pkey,
  1087. const ed25519_public_key_t *master_id_pkey,
  1088. const uint8_t *rsa_id_digest))
  1089. {
  1090. uint8_t *cc = tor_malloc(crypto_pk_keysize(onion_pkey));
  1091. int cc_len =
  1092. crypto_pk_public_checksig(onion_pkey,
  1093. (char*)cc,
  1094. crypto_pk_keysize(onion_pkey),
  1095. (const char*)crosscert,
  1096. crosscert_len);
  1097. if (cc_len < 0) {
  1098. goto err;
  1099. }
  1100. if (cc_len < DIGEST_LEN + ED25519_PUBKEY_LEN) {
  1101. log_warn(LD_DIR, "Short signature on cross-certification with TAP key");
  1102. goto err;
  1103. }
  1104. if (tor_memneq(cc, rsa_id_digest, DIGEST_LEN) ||
  1105. tor_memneq(cc + DIGEST_LEN, master_id_pkey->pubkey,
  1106. ED25519_PUBKEY_LEN)) {
  1107. log_warn(LD_DIR, "Incorrect cross-certification with TAP key");
  1108. goto err;
  1109. }
  1110. tor_free(cc);
  1111. return 0;
  1112. err:
  1113. tor_free(cc);
  1114. return -1;
  1115. }
  1116. void
  1117. routerkeys_free_all(void)
  1118. {
  1119. ed25519_keypair_free(master_identity_key);
  1120. ed25519_keypair_free(master_signing_key);
  1121. ed25519_keypair_free(current_auth_key);
  1122. tor_cert_free(signing_key_cert);
  1123. tor_cert_free(link_cert_cert);
  1124. tor_cert_free(auth_key_cert);
  1125. tor_free(rsa_ed_crosscert);
  1126. master_identity_key = master_signing_key = NULL;
  1127. current_auth_key = NULL;
  1128. signing_key_cert = link_cert_cert = auth_key_cert = NULL;
  1129. rsa_ed_crosscert = NULL; // redundant
  1130. rsa_ed_crosscert_len = 0;
  1131. }