diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/README.UPDATING | 10 | ||||
-rw-r--r-- | src/src/tls-gnu.c | 34 |
2 files changed, 42 insertions, 2 deletions
diff --git a/src/README.UPDATING b/src/README.UPDATING index 2f6e57629..fadf59aa9 100644 --- a/src/README.UPDATING +++ b/src/README.UPDATING @@ -26,6 +26,16 @@ The rest of this document contains information about changes in 4.xx releases that might affect a running system. +Exim version 4.77 +----------------- + + * GnuTLS will now attempt to use TLS 1.2 and TLS 1.1 before TLS 1.0 and SSL3, + if supported by your GnuTLS library. Use the existing + "gnutls_require_protocols" option to downgrade this if that will be a + problem. Prior to this release, supported values were "TLS1" and "SSL3", + so you should be able to update configuration prior to update. + + Exim version 4.74 ----------------- diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c index bf10526e9..4de9d4f68 100644 --- a/src/src/tls-gnu.c +++ b/src/src/tls-gnu.c @@ -12,6 +12,13 @@ is based on a patch that was contributed by Nikos Mavroyanopoulos. No cryptographic code is included in Exim. All this module does is to call functions from the GnuTLS library. */ +/* Note: This appears to be using an old API from compat.h; it is likely that +someone familiary with GnuTLS programming could rework a lot of this to a +modern API and perhaps remove the explicit knowledge of crypto algorithms from +Exim. Such a re-work would be most welcome and we'd sacrifice support for +older GnuTLS releases without too many qualms -- maturity and experience +in crypto libraries tends to improve their robustness against attack. +Frankly, if you maintain it, you decide what's supported and what isn't. */ /* Heading stuff for GnuTLS */ @@ -46,6 +53,13 @@ static int verify_requirement; and space into which it can be copied and altered. */ static const int default_proto_priority[16] = { + /* These are gnutls_protocol_t enum values */ +#if GNUTLS_VERSION_MAJOR > 1 || GNUTLS_VERSION_MINOR >= 7 + GNUTLS_TLS1_2, +#endif +#if GNUTLS_VERSION_MAJOR > 1 || GNUTLS_VERSION_MINOR >= 2 + GNUTLS_TLS1_1, +#endif GNUTLS_TLS1, GNUTLS_SSL3, 0 }; @@ -89,11 +103,27 @@ typedef struct pri_item { } pri_item; -static int tls1_codes[] = { GNUTLS_TLS1, 0 }; +#if GNUTLS_VERSION_MAJOR > 1 || GNUTLS_VERSION_MINOR >= 7 +static int tls1_2_codes[] = { GNUTLS_TLS1_2, 0 }; +#endif +#if GNUTLS_VERSION_MAJOR > 1 || GNUTLS_VERSION_MINOR >= 2 +static int tls1_1_codes[] = { GNUTLS_TLS1_1, 0 }; +#endif +/* more recent libraries define this as an equivalent value to the +canonical GNUTLS_TLS1_0; since they're the same, we stick to the +older name. */ +static int tls1_0_codes[] = { GNUTLS_TLS1, 0 }; static int ssl3_codes[] = { GNUTLS_SSL3, 0 }; static pri_item proto_index[] = { - { US"TLS1", tls1_codes }, +#if GNUTLS_VERSION_MAJOR > 1 || GNUTLS_VERSION_MINOR >= 7 + { US"TLS1.2", tls1_2_codes }, +#endif +#if GNUTLS_VERSION_MAJOR > 1 || GNUTLS_VERSION_MINOR >= 2 + { US"TLS1.1", tls1_1_codes }, +#endif + { US"TLS1.0", tls1_0_codes }, + { US"TLS1", tls1_0_codes }, { US"SSL3", ssl3_codes } }; |