January 2012 - tor-commits - lists.torproject.org

[tor/master] Merge branch 'bug4822_021_v2_squashed' into maint-0.2.1
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit b839ace7d092fe073b66a2d7d329644e82ec843b Merge: df17b62 4752b34 Author: Nick Mathewson <nickm(a)torproject.org> Date: Thu Jan 5 14:11:42 2012 -0500 Merge branch 'bug4822_021_v2_squashed' into maint-0.2.1 changes/bug4822 | 13 +++++++++++++ src/common/tortls.c | 37 ++++++++++++++++++++++++++++++++++--- 2 files changed, 47 insertions(+), 3 deletions(-)

1 0

[tor/master] Merge remote-tracking branch 'origin/maint-0.2.2'
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit ef69f2f2ab588ea51ade8587c8c0af2064c32c85 Merge: 13b2aa6 ccd8289 Author: Nick Mathewson <nickm(a)torproject.org> Date: Thu Jan 5 14:17:44 2012 -0500 Merge remote-tracking branch 'origin/maint-0.2.2' changes/bug4822 | 13 +++++++++++++ src/common/tortls.c | 37 ++++++++++++++++++++++++++++++++++--- 2 files changed, 47 insertions(+), 3 deletions(-) diff --cc src/common/tortls.c index 2b46612,ef61f71..b7cd835 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@@ -1158,20 -771,20 +1168,24 @@@ tor_tls_context_new(crypto_pk_env_t *id result = tor_malloc_zero(sizeof(tor_tls_context_t)); result->refcnt = 1; if (!is_client) { - result->my_cert = X509_dup(cert); - result->my_id_cert = X509_dup(idcert); - result->key = crypto_pk_dup_key(rsa); + result->my_link_cert = tor_cert_new(X509_dup(cert)); + result->my_id_cert = tor_cert_new(X509_dup(idcert)); + result->my_auth_cert = tor_cert_new(X509_dup(authcert)); + if (!result->my_link_cert || !result->my_id_cert || !result->my_auth_cert) + goto error; + result->link_key = crypto_pk_dup_key(rsa); + result->auth_key = crypto_pk_dup_key(rsa_auth); } - #ifdef EVERYONE_HAS_AES - /* Tell OpenSSL to only use TLS1 */ + #if 0 + /* Tell OpenSSL to only use TLS1. This would actually break compatibility + * with clients that are configured to use SSLv23_method(), so we should + * probably never use it. + */ if (!(result->ctx = SSL_CTX_new(TLSv1_method()))) goto error; - #else + #endif + /* Tell OpenSSL to use SSL3 or TLS1 but not SSL2. */ if (!(result->ctx = SSL_CTX_new(SSLv23_method()))) goto error;

1 0

[tor/maint-0.2.2] Disable SSLv3 when using a not-up-to-date openssl
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit db78fe45898a6d03727f8db68642bfebdfc10bf8 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Jan 4 17:15:50 2012 -0500 Disable SSLv3 when using a not-up-to-date openssl This is to address bug 4822, and CVE-2011-4576. --- src/common/tortls.c | 31 ++++++++++++++++++++++++++++--- 1 files changed, 28 insertions(+), 3 deletions(-) diff --git a/src/common/tortls.c b/src/common/tortls.c index cc805f8..22b0e31 100644 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@ -64,6 +64,16 @@ #define ADDR(tls) (((tls) && (tls)->address) ? tls->address : "peer") +#if (OPENSSL_VERSION_NUMBER < 0x0090813fL || \ + (OPENSSL_VERSION_NUMBER >= 0x00909000L && \ + OPENSSL_VERSION_NUMBER < 0x1000006fL)) +/* This is a version of OpenSSL before 0.9.8s/1.0.0f. It does not have + * the CVE-2011-4657 fix, and as such it can't use RELEASE_BUFFERS and + * SSL3 safely at the same time. + */ +#define DISABLE_SSL3_HANDSHAKE +#endif + /* We redefine these so that we can run correctly even if the vendor gives us * a version of OpenSSL that does not match its header files. (Apple: I am * looking at you.) @@ -739,16 +749,31 @@ tor_tls_context_new(crypto_pk_env_t *identity, unsigned int key_lifetime, result->key = crypto_pk_dup_key(rsa); } -#ifdef EVERYONE_HAS_AES - /* Tell OpenSSL to only use TLS1 */ +#if 0 + /* Tell OpenSSL to only use TLS1. This would actually break compatibility + * with clients that are configured to use SSLv23_method(), so we should + * probably never use it. + */ if (!(result->ctx = SSL_CTX_new(TLSv1_method()))) goto error; -#else +#endif + /* Tell OpenSSL to use SSL3 or TLS1 but not SSL2. */ if (!(result->ctx = SSL_CTX_new(SSLv23_method()))) goto error; SSL_CTX_set_options(result->ctx, SSL_OP_NO_SSLv2); + + if ( +#ifdef DISABLE_SSL3_HANDSHAKE + 1 || #endif + SSLeay() < 0x0090813fL || + (SSLeay() >= 0x00909000L && + SSLeay() < 0x1000006fL)) { + /* And not SSL3 if it's subject to CVE-2011-4657. */ + SSL_CTX_set_options(result->ctx, SSL_OP_NO_SSLv3); + } + SSL_CTX_set_options(result->ctx, SSL_OP_SINGLE_DH_USE); #ifdef SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION

1 0

[tor/maint-0.2.2] Add a changes file for bug4822
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit 0a00678e56ec3030b9028a7188f68ab6c10a3fa3 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Jan 4 21:17:52 2012 -0500 Add a changes file for bug4822 --- changes/bug4822 | 13 +++++++++++++ 1 files changed, 13 insertions(+), 0 deletions(-) diff --git a/changes/bug4822 b/changes/bug4822 new file mode 100644 index 0000000..73f43f0 --- /dev/null +++ b/changes/bug4822 @@ -0,0 +1,13 @@ + o Major security workaround: + - When building or running with any version of OpenSSL earlier + than 0.9.8s or 1.0.0f, disable SSLv3 support. These versions had + a bug (CVE-2011-4576) in which their block cipher padding + included uninitialized data, potentially leaking sensitive + information to any peer with whom they made a SSLv3 + connection. Tor does not use SSL v3 by default, but a hostile + client or server could force an SSLv3 connection in order to + gain information that they shouldn't have been able to get. The + best solution here is to upgrade to OpenSSL 0.9.8s or 1.0.0f (or + later). But when building or running with a non-upgraded + OpenSSL, we should instead make sure that the bug can't happen + by disabling SSLv3 entirely.

1 0

[tor/maint-0.2.2] Log at info level when disabling SSLv3
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit 4752b348793f599cbdc93d0503d18def03e45c7a Author: Robert Ransom <rransom.8774(a)gmail.com> Date: Wed Jan 4 20:41:28 2012 -0800 Log at info level when disabling SSLv3 --- src/common/tortls.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/src/common/tortls.c b/src/common/tortls.c index 22b0e31..d88a59b 100644 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@ -771,6 +771,12 @@ tor_tls_context_new(crypto_pk_env_t *identity, unsigned int key_lifetime, (SSLeay() >= 0x00909000L && SSLeay() < 0x1000006fL)) { /* And not SSL3 if it's subject to CVE-2011-4657. */ + log_info(LD_NET, "Disabling SSLv3 because this OpenSSL version " + "might otherwise be vulnerable to CVE-2011-4657 " + "(compile-time version %08lx (%s); " + "runtime version %08lx (%s))", + OPENSSL_VERSION_NUMBER, OPENSSL_VERSION_TEXT, + SSLeay(), SSLeay_version(SSLEAY_VERSION)); SSL_CTX_set_options(result->ctx, SSL_OP_NO_SSLv3); }

1 0

[tor/maint-0.2.2] Merge branch 'bug4822_021_v2_squashed' into maint-0.2.1
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit b839ace7d092fe073b66a2d7d329644e82ec843b Merge: df17b62 4752b34 Author: Nick Mathewson <nickm(a)torproject.org> Date: Thu Jan 5 14:11:42 2012 -0500 Merge branch 'bug4822_021_v2_squashed' into maint-0.2.1 changes/bug4822 | 13 +++++++++++++ src/common/tortls.c | 37 ++++++++++++++++++++++++++++++++++--- 2 files changed, 47 insertions(+), 3 deletions(-)

1 0

[tor/maint-0.2.2] Merge remote-tracking branch 'origin/maint-0.2.1' into maint-0.2.2
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit ccd8289958b6d81cd5575c15dc6c1218d8ecb2d0 Merge: a1074c7 b839ace Author: Nick Mathewson <nickm(a)torproject.org> Date: Thu Jan 5 14:16:30 2012 -0500 Merge remote-tracking branch 'origin/maint-0.2.1' into maint-0.2.2 changes/bug4822 | 13 +++++++++++++ src/common/tortls.c | 37 ++++++++++++++++++++++++++++++++++--- 2 files changed, 47 insertions(+), 3 deletions(-)

1 0

[tor/maint-0.2.1] Log at info level when disabling SSLv3
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit 4752b348793f599cbdc93d0503d18def03e45c7a Author: Robert Ransom <rransom.8774(a)gmail.com> Date: Wed Jan 4 20:41:28 2012 -0800 Log at info level when disabling SSLv3 --- src/common/tortls.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/src/common/tortls.c b/src/common/tortls.c index 22b0e31..d88a59b 100644 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@ -771,6 +771,12 @@ tor_tls_context_new(crypto_pk_env_t *identity, unsigned int key_lifetime, (SSLeay() >= 0x00909000L && SSLeay() < 0x1000006fL)) { /* And not SSL3 if it's subject to CVE-2011-4657. */ + log_info(LD_NET, "Disabling SSLv3 because this OpenSSL version " + "might otherwise be vulnerable to CVE-2011-4657 " + "(compile-time version %08lx (%s); " + "runtime version %08lx (%s))", + OPENSSL_VERSION_NUMBER, OPENSSL_VERSION_TEXT, + SSLeay(), SSLeay_version(SSLEAY_VERSION)); SSL_CTX_set_options(result->ctx, SSL_OP_NO_SSLv3); }

1 0

[tor/maint-0.2.1] Add a changes file for bug4822
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit 0a00678e56ec3030b9028a7188f68ab6c10a3fa3 Author: Nick Mathewson <nickm(a)torproject.org> Date: Wed Jan 4 21:17:52 2012 -0500 Add a changes file for bug4822 --- changes/bug4822 | 13 +++++++++++++ 1 files changed, 13 insertions(+), 0 deletions(-) diff --git a/changes/bug4822 b/changes/bug4822 new file mode 100644 index 0000000..73f43f0 --- /dev/null +++ b/changes/bug4822 @@ -0,0 +1,13 @@ + o Major security workaround: + - When building or running with any version of OpenSSL earlier + than 0.9.8s or 1.0.0f, disable SSLv3 support. These versions had + a bug (CVE-2011-4576) in which their block cipher padding + included uninitialized data, potentially leaking sensitive + information to any peer with whom they made a SSLv3 + connection. Tor does not use SSL v3 by default, but a hostile + client or server could force an SSLv3 connection in order to + gain information that they shouldn't have been able to get. The + best solution here is to upgrade to OpenSSL 0.9.8s or 1.0.0f (or + later). But when building or running with a non-upgraded + OpenSSL, we should instead make sure that the bug can't happen + by disabling SSLv3 entirely.

1 0

[tor/maint-0.2.1] Merge branch 'bug4822_021_v2_squashed' into maint-0.2.1
by nickm＠torproject.org 05 Jan '12

05 Jan '12

commit b839ace7d092fe073b66a2d7d329644e82ec843b Merge: df17b62 4752b34 Author: Nick Mathewson <nickm(a)torproject.org> Date: Thu Jan 5 14:11:42 2012 -0500 Merge branch 'bug4822_021_v2_squashed' into maint-0.2.1 changes/bug4822 | 13 +++++++++++++ src/common/tortls.c | 37 ++++++++++++++++++++++++++++++++++--- 2 files changed, 47 insertions(+), 3 deletions(-)

1 0