Commit 7aa496a2 authored by Alexander Hansen Færøy's avatar Alexander Hansen Færøy 💬 Committed by David Goulet
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Fix TROVE-2023-004: Remote crash when compiled against OpenSSL 



Fixes #40874

Signed-off-by: David Goulet's avatarDavid Goulet <dgoulet@torproject.org>
parent d7777c12

changes/ticket40874

0 → 100644
+3 −0
Original line number Diff line number Diff line 
  o Major bugfixes (TROVE-2023-004, relay):

    - Mitigate an issue when Tor compiled with OpenSSL can crash during

      handshake with a remote relay. Fixes bug 40874; bugfix on 0.2.7.2-alpha.

src/feature/relay/relay_handshake.c

+1 −0
Original line number Diff line number Diff line
@@ -414,6 +414,7 @@ connection_or_compute_authenticate_cell_body(or_connection_t *conn, 
      log_fn(LOG_PROTOCOL_WARN, LD_OR, "Somebody asked us for an older TLS "

         "authentication method (AUTHTYPE_RSA_SHA256_TLSSECRET) "

         "which we don't support.");

      goto err;

    }

  } else {

    char label[128];

src/lib/tls/tortls_openssl.c

+29 −3
Original line number Diff line number Diff line
@@ -1649,9 +1649,35 @@ tor_tls_get_tlssecrets,(tor_tls_t *tls, uint8_t *secrets_out)) 
  const size_t client_random_len = SSL_get_client_random(ssl, NULL, 0);

  const size_t master_key_len = SSL_SESSION_get_master_key(session, NULL, 0);



  tor_assert(server_random_len);

  tor_assert(client_random_len);

  tor_assert(master_key_len);

  if (BUG(! server_random_len)) {

    log_warn(LD_NET, "Missing server randomness after handshake "

                     "using %s (cipher: %s, server: %s) from %s",

                     SSL_get_version(ssl),

                     SSL_get_cipher_name(ssl),

                     tls->isServer ? "true" : "false",

                     ADDR(tls));

    return -1;

  }



  if (BUG(! client_random_len)) {

    log_warn(LD_NET, "Missing client randomness after handshake "

                     "using %s (cipher: %s, server: %s) from %s",

                     SSL_get_version(ssl),

                     SSL_get_cipher_name(ssl),

                     tls->isServer ? "true" : "false",

                     ADDR(tls));

    return -1;

  }



  if (BUG(! master_key_len)) {

    log_warn(LD_NET, "Missing master key after handshake "

                     "using %s (cipher: %s, server: %s) from %s",

                     SSL_get_version(ssl),

                     SSL_get_cipher_name(ssl),

                     tls->isServer ? "true" : "false",

                     ADDR(tls));

    return -1;

  }



  len = client_random_len + server_random_len + strlen(TLSSECRET_MAGIC) + 1;

  tor_assert(len <= sizeof(buf));