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- /* Copyright (c) 2014-2016, The Tor Project, Inc. */
- /* See LICENSE for licensing information */
- /**
- * \file torcert.c
- *
- * \brief Implementation for ed25519-signed certificates as used in the Tor
- * protocol.
- *
- * This certificate format is designed to be simple and compact; it's
- * documented in tor-spec.txt in the torspec.git repository. All of the
- * certificates in this format are signed with an Ed25519 key; the
- * contents themselves may be another Ed25519 key, a digest of a
- * RSA key, or some other material.
- *
- * In this module there is also support for a crooss-certification of
- * Ed25519 identities using (older) RSA1024 identities.
- *
- * Tor uses other types of certificate too, beyond those described in this
- * module. Notably, our use of TLS requires us to touch X.509 certificates,
- * even though sensible people would stay away from those. Our X.509
- * certificates are represented with tor_x509_cert_t, and implemented in
- * tortls.c. We also have a separate certificate type that authorities
- * use to authenticate their RSA signing keys with their RSA identity keys:
- * that one is authority_cert_t, and it's mostly handled in routerlist.c.
- */
- #include "or.h"
- #include "config.h"
- #include "crypto.h"
- #include "torcert.h"
- #include "ed25519_cert.h"
- #include "torlog.h"
- #include "util.h"
- #include "compat.h"
- #include "link_handshake.h"
- /** Helper for tor_cert_create(): signs any 32 bytes, not just an ed25519
- * key.
- */
- static tor_cert_t *
- tor_cert_sign_impl(const ed25519_keypair_t *signing_key,
- uint8_t cert_type,
- uint8_t signed_key_type,
- const uint8_t signed_key_info[32],
- time_t now, time_t lifetime,
- uint32_t flags)
- {
- tor_cert_t *torcert = NULL;
- ed25519_cert_t *cert = ed25519_cert_new();
- cert->cert_type = cert_type;
- cert->exp_field = (uint32_t) CEIL_DIV(now + lifetime, 3600);
- cert->cert_key_type = signed_key_type;
- memcpy(cert->certified_key, signed_key_info, 32);
- if (flags & CERT_FLAG_INCLUDE_SIGNING_KEY) {
- ed25519_cert_extension_t *ext = ed25519_cert_extension_new();
- ext->ext_type = CERTEXT_SIGNED_WITH_KEY;
- memcpy(ext->un_signing_key, signing_key->pubkey.pubkey, 32);
- ed25519_cert_add_ext(cert, ext);
- ++cert->n_extensions;
- }
- const ssize_t alloc_len = ed25519_cert_encoded_len(cert);
- tor_assert(alloc_len > 0);
- uint8_t *encoded = tor_malloc(alloc_len);
- const ssize_t real_len = ed25519_cert_encode(encoded, alloc_len, cert);
- if (real_len < 0)
- goto err;
- tor_assert(real_len == alloc_len);
- tor_assert(real_len > ED25519_SIG_LEN);
- uint8_t *sig = encoded + (real_len - ED25519_SIG_LEN);
- tor_assert(tor_mem_is_zero((char*)sig, ED25519_SIG_LEN));
- ed25519_signature_t signature;
- if (ed25519_sign(&signature, encoded,
- real_len-ED25519_SIG_LEN, signing_key)<0) {
- log_warn(LD_BUG, "Can't sign certificate");
- goto err;
- }
- memcpy(sig, signature.sig, ED25519_SIG_LEN);
- torcert = tor_cert_parse(encoded, real_len);
- if (! torcert) {
- log_warn(LD_BUG, "Generated a certificate we cannot parse");
- goto err;
- }
- if (tor_cert_checksig(torcert, &signing_key->pubkey, now) < 0) {
- log_warn(LD_BUG, "Generated a certificate whose signature we can't check");
- goto err;
- }
- tor_free(encoded);
- goto done;
- err:
- tor_cert_free(torcert);
- torcert = NULL;
- done:
- ed25519_cert_free(cert);
- tor_free(encoded);
- return torcert;
- }
- /**
- * Create and return a new new certificate of type <b>cert_type</b> to
- * authenticate <b>signed_key</b> using the key <b>signing_key</b>. The
- * certificate should remain valid for at least <b>lifetime</b> seconds after
- * <b>now</b>.
- *
- * If CERT_FLAG_INCLUDE_SIGNING_KEY is set in <b>flags</b>, embed
- * the public part of <b>signing_key</b> in the certificate.
- */
- tor_cert_t *
- tor_cert_create(const ed25519_keypair_t *signing_key,
- uint8_t cert_type,
- const ed25519_public_key_t *signed_key,
- time_t now, time_t lifetime,
- uint32_t flags)
- {
- return tor_cert_sign_impl(signing_key, cert_type,
- SIGNED_KEY_TYPE_ED25519, signed_key->pubkey,
- now, lifetime, flags);
- }
- /** Release all storage held for <b>cert</b>. */
- void
- tor_cert_free(tor_cert_t *cert)
- {
- if (! cert)
- return;
- if (cert->encoded)
- memwipe(cert->encoded, 0, cert->encoded_len);
- tor_free(cert->encoded);
- memwipe(cert, 0, sizeof(tor_cert_t));
- tor_free(cert);
- }
- /** Parse a certificate encoded with <b>len</b> bytes in <b>encoded</b>. */
- tor_cert_t *
- tor_cert_parse(const uint8_t *encoded, const size_t len)
- {
- tor_cert_t *cert = NULL;
- ed25519_cert_t *parsed = NULL;
- ssize_t got_len = ed25519_cert_parse(&parsed, encoded, len);
- if (got_len < 0 || (size_t) got_len != len)
- goto err;
- cert = tor_malloc_zero(sizeof(tor_cert_t));
- cert->encoded = tor_memdup(encoded, len);
- cert->encoded_len = len;
- memcpy(cert->signed_key.pubkey, parsed->certified_key, 32);
- int64_t valid_until_64 = ((int64_t)parsed->exp_field) * 3600;
- #if SIZEOF_TIME_T < SIZEOF_INT64_T
- if (valid_until_64 > TIME_MAX)
- valid_until_64 = TIME_MAX - 1;
- #endif
- cert->valid_until = (time_t) valid_until_64;
- cert->cert_type = parsed->cert_type;
- for (unsigned i = 0; i < ed25519_cert_getlen_ext(parsed); ++i) {
- ed25519_cert_extension_t *ext = ed25519_cert_get_ext(parsed, i);
- if (ext->ext_type == CERTEXT_SIGNED_WITH_KEY) {
- if (cert->signing_key_included)
- goto err;
- cert->signing_key_included = 1;
- memcpy(cert->signing_key.pubkey, ext->un_signing_key, 32);
- } else if (ext->ext_flags & CERTEXT_FLAG_AFFECTS_VALIDATION) {
- /* Unrecognized extension with affects_validation set */
- goto err;
- }
- }
- goto done;
- err:
- tor_cert_free(cert);
- cert = NULL;
- done:
- ed25519_cert_free(parsed);
- return cert;
- }
- /** Fill in <b>checkable_out</b> with the information needed to check
- * the signature on <b>cert</b> with <b>pubkey</b>.
- *
- * On success, if <b>expiration_out</b> is provided, and it is some time
- * _after_ the expiration time of this certificate, set it to the
- * expiration time of this certificate.
- */
- int
- tor_cert_get_checkable_sig(ed25519_checkable_t *checkable_out,
- const tor_cert_t *cert,
- const ed25519_public_key_t *pubkey,
- time_t *expiration_out)
- {
- if (! pubkey) {
- if (cert->signing_key_included)
- pubkey = &cert->signing_key;
- else
- return -1;
- }
- checkable_out->msg = cert->encoded;
- checkable_out->pubkey = pubkey;
- tor_assert(cert->encoded_len > ED25519_SIG_LEN);
- const size_t signed_len = cert->encoded_len - ED25519_SIG_LEN;
- checkable_out->len = signed_len;
- memcpy(checkable_out->signature.sig,
- cert->encoded + signed_len, ED25519_SIG_LEN);
- if (expiration_out) {
- *expiration_out = MIN(*expiration_out, cert->valid_until);
- }
- return 0;
- }
- /** Validates the signature on <b>cert</b> with <b>pubkey</b> relative to the
- * current time <b>now</b>. (If <b>now</b> is 0, do not check the expiration
- * time.) Return 0 on success, -1 on failure. Sets flags in <b>cert</b> as
- * appropriate.
- */
- int
- tor_cert_checksig(tor_cert_t *cert,
- const ed25519_public_key_t *pubkey, time_t now)
- {
- ed25519_checkable_t checkable;
- int okay;
- time_t expires = TIME_MAX;
- if (tor_cert_get_checkable_sig(&checkable, cert, pubkey, &expires) < 0)
- return -1;
- if (now && now > expires) {
- cert->cert_expired = 1;
- return -1;
- }
- if (ed25519_checksig_batch(&okay, &checkable, 1) < 0) {
- cert->sig_bad = 1;
- return -1;
- } else {
- cert->sig_ok = 1;
- /* Only copy the checkable public key when it is different from the signing
- * key of the certificate to avoid undefined behavior. */
- if (cert->signing_key.pubkey != checkable.pubkey->pubkey) {
- memcpy(cert->signing_key.pubkey, checkable.pubkey->pubkey, 32);
- }
- cert->cert_valid = 1;
- return 0;
- }
- }
- /** Return a new copy of <b>cert</b> */
- tor_cert_t *
- tor_cert_dup(const tor_cert_t *cert)
- {
- tor_cert_t *newcert = tor_memdup(cert, sizeof(tor_cert_t));
- if (cert->encoded)
- newcert->encoded = tor_memdup(cert->encoded, cert->encoded_len);
- return newcert;
- }
- /** Return true iff cert1 and cert2 are the same cert. */
- int
- tor_cert_eq(const tor_cert_t *cert1, const tor_cert_t *cert2)
- {
- tor_assert(cert1);
- tor_assert(cert2);
- return cert1->encoded_len == cert2->encoded_len &&
- tor_memeq(cert1->encoded, cert2->encoded, cert1->encoded_len);
- }
- /** Return true iff cert1 and cert2 are the same cert, or if they are both
- * NULL. */
- int
- tor_cert_opt_eq(const tor_cert_t *cert1, const tor_cert_t *cert2)
- {
- if (cert1 == NULL && cert2 == NULL)
- return 1;
- if (!cert1 || !cert2)
- return 0;
- return tor_cert_eq(cert1, cert2);
- }
- #define RSA_ED_CROSSCERT_PREFIX "Tor TLS RSA/Ed25519 cross-certificate"
- /** Create new cross-certification object to certify <b>ed_key</b> as the
- * master ed25519 identity key for the RSA identity key <b>rsa_key</b>.
- * Allocates and stores the encoded certificate in *<b>cert</b>, and returns
- * the number of bytes stored. Returns negative on error.*/
- ssize_t
- tor_make_rsa_ed25519_crosscert(const ed25519_public_key_t *ed_key,
- const crypto_pk_t *rsa_key,
- time_t expires,
- uint8_t **cert)
- {
- uint8_t *res;
- rsa_ed_crosscert_t *cc = rsa_ed_crosscert_new();
- memcpy(cc->ed_key, ed_key->pubkey, ED25519_PUBKEY_LEN);
- cc->expiration = (uint32_t) CEIL_DIV(expires, 3600);
- cc->sig_len = crypto_pk_keysize(rsa_key);
- rsa_ed_crosscert_setlen_sig(cc, crypto_pk_keysize(rsa_key));
- ssize_t alloc_sz = rsa_ed_crosscert_encoded_len(cc);
- tor_assert(alloc_sz > 0);
- res = tor_malloc_zero(alloc_sz);
- ssize_t sz = rsa_ed_crosscert_encode(res, alloc_sz, cc);
- tor_assert(sz > 0 && sz <= alloc_sz);
- crypto_digest_t *d = crypto_digest256_new(DIGEST_SHA256);
- crypto_digest_add_bytes(d, RSA_ED_CROSSCERT_PREFIX,
- strlen(RSA_ED_CROSSCERT_PREFIX));
- const int signed_part_len = 32 + 4;
- crypto_digest_add_bytes(d, (char*)res, signed_part_len);
- uint8_t digest[DIGEST256_LEN];
- crypto_digest_get_digest(d, (char*)digest, sizeof(digest));
- crypto_digest_free(d);
- int siglen = crypto_pk_private_sign(rsa_key,
- (char*)rsa_ed_crosscert_getarray_sig(cc),
- rsa_ed_crosscert_getlen_sig(cc),
- (char*)digest, sizeof(digest));
- tor_assert(siglen > 0 && siglen <= (int)crypto_pk_keysize(rsa_key));
- tor_assert(siglen <= UINT8_MAX);
- cc->sig_len = siglen;
- rsa_ed_crosscert_setlen_sig(cc, siglen);
- sz = rsa_ed_crosscert_encode(res, alloc_sz, cc);
- rsa_ed_crosscert_free(cc);
- *cert = res;
- return sz;
- }
- /**
- * Check whether the <b>crosscert_len</b> byte certificate in <b>crosscert</b>
- * is in fact a correct cross-certification of <b>master_key</b> using
- * the RSA key <b>rsa_id_key</b>.
- *
- * Also reject the certificate if it expired before
- * <b>reject_if_expired_before</b>.
- *
- * Return 0 on success, negative on failure.
- */
- int
- rsa_ed25519_crosscert_check(const uint8_t *crosscert,
- const size_t crosscert_len,
- const crypto_pk_t *rsa_id_key,
- const ed25519_public_key_t *master_key,
- const time_t reject_if_expired_before)
- {
- rsa_ed_crosscert_t *cc = NULL;
- int rv;
- #define ERR(code, s) \
- do { \
- log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, \
- "Received a bad RSA->Ed25519 crosscert: %s", \
- (s)); \
- rv = (code); \
- goto err; \
- } while (0)
- if (BUG(crypto_pk_keysize(rsa_id_key) > PK_BYTES))
- return -1;
- if (BUG(!crosscert))
- return -1;
- ssize_t parsed_len = rsa_ed_crosscert_parse(&cc, crosscert, crosscert_len);
- if (parsed_len < 0 || crosscert_len != (size_t)parsed_len) {
- ERR(-2, "Unparseable or overlong crosscert");
- }
- if (tor_memneq(rsa_ed_crosscert_getarray_ed_key(cc),
- master_key->pubkey,
- ED25519_PUBKEY_LEN)) {
- ERR(-3, "Crosscert did not match Ed25519 key");
- }
- const uint32_t expiration_date = rsa_ed_crosscert_get_expiration(cc);
- const uint64_t expiration_time = expiration_date * 3600;
- if (reject_if_expired_before < 0 ||
- expiration_time < (uint64_t)reject_if_expired_before) {
- ERR(-4, "Crosscert is expired");
- }
- const uint8_t *eos = rsa_ed_crosscert_get_end_of_signed(cc);
- const uint8_t *sig = rsa_ed_crosscert_getarray_sig(cc);
- const uint8_t siglen = rsa_ed_crosscert_get_sig_len(cc);
- tor_assert(eos >= crosscert);
- tor_assert((size_t)(eos - crosscert) <= crosscert_len);
- tor_assert(siglen == rsa_ed_crosscert_getlen_sig(cc));
- /* Compute the digest */
- uint8_t digest[DIGEST256_LEN];
- crypto_digest_t *d = crypto_digest256_new(DIGEST_SHA256);
- crypto_digest_add_bytes(d, RSA_ED_CROSSCERT_PREFIX,
- strlen(RSA_ED_CROSSCERT_PREFIX));
- crypto_digest_add_bytes(d, (char*)crosscert, eos-crosscert);
- crypto_digest_get_digest(d, (char*)digest, sizeof(digest));
- crypto_digest_free(d);
- /* Now check the signature */
- uint8_t signed_[PK_BYTES];
- int signed_len = crypto_pk_public_checksig(rsa_id_key,
- (char*)signed_, sizeof(signed_),
- (char*)sig, siglen);
- if (signed_len < DIGEST256_LEN) {
- ERR(-5, "Bad signature, or length of signed data not as expected");
- }
- if (tor_memneq(digest, signed_, DIGEST256_LEN)) {
- ERR(-6, "The signature was good, but it didn't match the data");
- }
- rv = 0;
- err:
- rsa_ed_crosscert_free(cc);
- return rv;
- }
- /** Construct and return a new empty or_handshake_certs object */
- or_handshake_certs_t *
- or_handshake_certs_new(void)
- {
- return tor_malloc_zero(sizeof(or_handshake_certs_t));
- }
- /** Release all storage held in <b>certs</b> */
- void
- or_handshake_certs_free(or_handshake_certs_t *certs)
- {
- if (!certs)
- return;
- tor_x509_cert_free(certs->auth_cert);
- tor_x509_cert_free(certs->link_cert);
- tor_x509_cert_free(certs->id_cert);
- tor_cert_free(certs->ed_id_sign);
- tor_cert_free(certs->ed_sign_link);
- tor_cert_free(certs->ed_sign_auth);
- tor_free(certs->ed_rsa_crosscert);
- memwipe(certs, 0xBD, sizeof(*certs));
- tor_free(certs);
- }
- #undef ERR
- #define ERR(s) \
- do { \
- log_fn(severity, LD_PROTOCOL, \
- "Received a bad CERTS cell: %s", \
- (s)); \
- return 0; \
- } while (0)
- int
- or_handshake_certs_rsa_ok(int severity,
- or_handshake_certs_t *certs,
- tor_tls_t *tls,
- time_t now)
- {
- tor_x509_cert_t *link_cert = certs->link_cert;
- tor_x509_cert_t *auth_cert = certs->auth_cert;
- tor_x509_cert_t *id_cert = certs->id_cert;
- if (certs->started_here) {
- if (! (id_cert && link_cert))
- ERR("The certs we wanted (ID, Link) were missing");
- if (! tor_tls_cert_matches_key(tls, link_cert))
- ERR("The link certificate didn't match the TLS public key");
- if (! tor_tls_cert_is_valid(severity, link_cert, id_cert, now, 0))
- ERR("The link certificate was not valid");
- if (! tor_tls_cert_is_valid(severity, id_cert, id_cert, now, 1))
- ERR("The ID certificate was not valid");
- } else {
- if (! (id_cert && auth_cert))
- ERR("The certs we wanted (ID, Auth) were missing");
- if (! tor_tls_cert_is_valid(LOG_PROTOCOL_WARN, auth_cert, id_cert, now, 1))
- ERR("The authentication certificate was not valid");
- if (! tor_tls_cert_is_valid(LOG_PROTOCOL_WARN, id_cert, id_cert, now, 1))
- ERR("The ID certificate was not valid");
- }
- return 1;
- }
- /** Check all the ed25519 certificates in <b>certs</b> against each other, and
- * against the peer certificate in <b>tls</b> if appropriate. On success,
- * return 0; on failure, return a negative value and warn at level
- * <b>severity</b> */
- int
- or_handshake_certs_ed25519_ok(int severity,
- or_handshake_certs_t *certs,
- tor_tls_t *tls,
- time_t now)
- {
- ed25519_checkable_t check[10];
- unsigned n_checkable = 0;
- time_t expiration = TIME_MAX;
- #define ADDCERT(cert, pk) \
- do { \
- tor_assert(n_checkable < ARRAY_LENGTH(check)); \
- if (tor_cert_get_checkable_sig(&check[n_checkable++], cert, pk, \
- &expiration) < 0) \
- ERR("Could not get checkable cert."); \
- } while (0)
- if (! certs->ed_id_sign || !certs->ed_id_sign->signing_key_included) {
- ERR("No Ed25519 signing key");
- }
- ADDCERT(certs->ed_id_sign, NULL);
- if (certs->started_here) {
- if (! certs->ed_sign_link)
- ERR("No Ed25519 link key");
- {
- /* check for a match with the TLS cert. */
- tor_x509_cert_t *peer_cert = tor_tls_get_peer_cert(tls);
- if (BUG(!peer_cert)) {
- /* This is a bug, because if we got to this point, we are a connection
- * that was initiated here, and we completed a TLS handshake. The
- * other side *must* have given us a certificate! */
- ERR("No x509 peer cert"); // LCOV_EXCL_LINE
- }
- const common_digests_t *peer_cert_digests =
- tor_x509_cert_get_cert_digests(peer_cert);
- int okay = tor_memeq(peer_cert_digests->d[DIGEST_SHA256],
- certs->ed_sign_link->signed_key.pubkey,
- DIGEST256_LEN);
- tor_x509_cert_free(peer_cert);
- if (!okay)
- ERR("Link certificate does not match TLS certificate");
- }
- ADDCERT(certs->ed_sign_link, &certs->ed_id_sign->signed_key);
- } else {
- if (! certs->ed_sign_auth)
- ERR("No Ed25519 link authentication key");
- ADDCERT(certs->ed_sign_auth, &certs->ed_id_sign->signed_key);
- }
- if (expiration < now) {
- ERR("At least one certificate expired.");
- }
- /* Okay, we've gotten ready to check all the Ed25519 certificates.
- * Now, we are going to check the RSA certificate's cross-certification
- * with the ED certificates.
- *
- * FFFF In the future, we might want to make this optional.
- */
- tor_x509_cert_t *rsa_id_cert = certs->id_cert;
- if (!rsa_id_cert) {
- ERR("Missing legacy RSA ID certificate");
- }
- if (! tor_tls_cert_is_valid(severity, rsa_id_cert, rsa_id_cert, now, 1)) {
- ERR("The legacy RSA ID certificate was not valid");
- }
- if (! certs->ed_rsa_crosscert) {
- ERR("Missing RSA->Ed25519 crosscert");
- }
- crypto_pk_t *rsa_id_key = tor_tls_cert_get_key(rsa_id_cert);
- if (!rsa_id_key) {
- ERR("RSA ID cert had no RSA key");
- }
- if (rsa_ed25519_crosscert_check(certs->ed_rsa_crosscert,
- certs->ed_rsa_crosscert_len,
- rsa_id_key,
- &certs->ed_id_sign->signing_key,
- now) < 0) {
- crypto_pk_free(rsa_id_key);
- ERR("Invalid RSA->Ed25519 crosscert");
- }
- crypto_pk_free(rsa_id_key);
- rsa_id_key = NULL;
- /* FFFF We could save a little time in the client case by queueing
- * this batch to check it later, along with the signature from the
- * AUTHENTICATE cell. That will change our data flow a bit, though,
- * so I say "postpone". */
- if (ed25519_checksig_batch(NULL, check, n_checkable) < 0) {
- ERR("At least one Ed25519 certificate was badly signed");
- }
- return 1;
- }
- /**
- * Check the Ed certificates and/or the RSA certificates, as appropriate. If
- * we obtained an Ed25519 identity, set *ed_id_out. If we obtained an RSA
- * identity, set *rs_id_out. Otherwise, set them both to NULL.
- */
- void
- or_handshake_certs_check_both(int severity,
- or_handshake_certs_t *certs,
- tor_tls_t *tls,
- time_t now,
- const ed25519_public_key_t **ed_id_out,
- const common_digests_t **rsa_id_out)
- {
- tor_assert(ed_id_out);
- tor_assert(rsa_id_out);
- *ed_id_out = NULL;
- *rsa_id_out = NULL;
- if (certs->ed_id_sign) {
- if (or_handshake_certs_ed25519_ok(severity, certs, tls, now)) {
- tor_assert(certs->ed_id_sign);
- tor_assert(certs->id_cert);
- *ed_id_out = &certs->ed_id_sign->signing_key;
- *rsa_id_out = tor_x509_cert_get_id_digests(certs->id_cert);
- /* If we reached this point, we did not look at any of the
- * subsidiary RSA certificates, so we'd better just remove them.
- */
- tor_x509_cert_free(certs->link_cert);
- tor_x509_cert_free(certs->auth_cert);
- certs->link_cert = certs->auth_cert = NULL;
- }
- /* We do _not_ fall through here. If you provided us Ed25519
- * certificates, we expect to verify them! */
- } else {
- /* No ed25519 keys given in the CERTS cell */
- if (or_handshake_certs_rsa_ok(severity, certs, tls, now)) {
- *rsa_id_out = tor_x509_cert_get_id_digests(certs->id_cert);
- }
- }
- }
- /* === ENCODING === */
- /* Encode the ed25519 certificate <b>cert</b> and put the newly allocated
- * string in <b>cert_str_out</b>. Return 0 on success else a negative value. */
- int
- tor_cert_encode_ed22519(const tor_cert_t *cert, char **cert_str_out)
- {
- int ret = -1;
- char *ed_cert_b64 = NULL;
- size_t ed_cert_b64_len;
- tor_assert(cert);
- tor_assert(cert_str_out);
- /* Get the encoded size and add the NUL byte. */
- ed_cert_b64_len = base64_encode_size(cert->encoded_len,
- BASE64_ENCODE_MULTILINE) + 1;
- ed_cert_b64 = tor_malloc_zero(ed_cert_b64_len);
- /* Base64 encode the encoded certificate. */
- if (base64_encode(ed_cert_b64, ed_cert_b64_len,
- (const char *) cert->encoded, cert->encoded_len,
- BASE64_ENCODE_MULTILINE) < 0) {
- log_err(LD_BUG, "Couldn't base64-encode ed22519 cert!");
- goto err;
- }
- /* Put everything together in a NUL terminated string. */
- tor_asprintf(cert_str_out,
- "-----BEGIN ED25519 CERT-----\n"
- "%s"
- "-----END ED25519 CERT-----",
- ed_cert_b64);
- /* Success! */
- ret = 0;
- err:
- tor_free(ed_cert_b64);
- return ret;
- }
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