diff options
Diffstat (limited to 'src/or/torcert.c')
| -rw-r--r-- | src/or/torcert.c | 150 |
1 files changed, 146 insertions, 4 deletions
diff --git a/src/or/torcert.c b/src/or/torcert.c index ef7775eb9e..cff1ed10c5 100644 --- a/src/or/torcert.c +++ b/src/or/torcert.c @@ -420,7 +420,7 @@ or_handshake_certs_new(void) return tor_malloc_zero(sizeof(or_handshake_certs_t)); } -/** DODCDOC */ +/** Release all storage held in <b>certs</b> */ void or_handshake_certs_free(or_handshake_certs_t *certs) { @@ -428,8 +428,14 @@ or_handshake_certs_free(or_handshake_certs_t *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); } @@ -477,9 +483,145 @@ or_handshake_certs_rsa_ok(int severity, 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(or_handshake_certs_t *certs) +or_handshake_certs_ed25519_ok(int severity, + or_handshake_certs_t *certs, + tor_tls_t *tls, + time_t now) { - (void) certs; - return 0; + 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 signing key"); + ADDCERT(certs->ed_id_sign, NULL); + + if (certs->started_here) { + if (! certs->ed_sign_link) + ERR("No link key"); + { + /* check for a match with the TLS cert. */ + tor_x509_cert_t *peer_cert = tor_tls_get_peer_cert(tls); + /* XXXX Does 'cert' match spec in this case? I hope so; if not, fix + * spec */ + if (!peer_cert) + ERR("No x509 peer cert"); + 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 link authentiction 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"); + } + crypto_pk_t *rsa_id_key = tor_tls_cert_get_key(rsa_id_cert); + + 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/missing RSA 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); + } + } + } |