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Viktor Dukhovnimattcaswell
Viktor Dukhovni
authored and
mattcaswell
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Disable EXPORT and LOW SSLv3+ ciphers by default
Reviewed-by: Emilia Käsper <[email protected]>
1 parent a82cfd6 commit abd5d8f

5 files changed

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‎CHANGES‎

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Changes between 1.0.1r and 1.0.1s [xx XXX xxxx]
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* Disable weak ciphers in SSLv3 and up in default builds of OpenSSL.
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Builds that are not configured with "enable-weak-ssl-ciphers" will not
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provide any "EXPORT" or "LOW" strength ciphers.
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[Viktor Dukhovni]
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* Disable SSLv2 default build, default negotiation and weak ciphers. SSLv2
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is by default disabled at build-time. Builds that are not configured with
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"enable-ssl2" will not support SSLv2. Even if "enable-ssl2" is used,

‎Configure‎

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@@ -58,6 +58,10 @@ my $usage="Usage: Configure [no-<cipher> ...] [enable-<cipher> ...] [experimenta
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# library and will be loaded in run-time by the OpenSSL library.
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# sctp include SCTP support
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# 386 generate 80386 code
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# enable-weak-ssl-ciphers
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# Enable EXPORT and LOW SSLv3 ciphers that are disabled by
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# default. Note, weak SSLv2 ciphers are unconditionally
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# disabled.
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# no-sse2 disables IA-32 SSE2 code, above option implies no-sse2
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# no-<cipher> build without specified algorithm (rsa, idea, rc5, ...)
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# -<xxx> +<xxx> compiler options are passed through
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"ssl2" => "default",
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"store" => "experimental",
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"unit-test" => "default",
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"weak-ssl-ciphers" => "default",
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"zlib" => "default",
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"zlib-dynamic" => "default"
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);

‎NEWS‎

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Major changes between OpenSSL 1.0.1r and OpenSSL 1.0.1s [under development]
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o Disable weak ciphers in SSLv3 and up in default builds of OpenSSL.
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o Disable SSLv2 default build, default negotiation and weak ciphers.
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Major changes between OpenSSL 1.0.1q and OpenSSL 1.0.1r [28 Jan 2016]

‎doc/apps/ciphers.pod‎

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@@ -136,34 +136,46 @@ than 128 bits, and some cipher suites with 128-bit keys.
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=item B<LOW>
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"low" encryption cipher suites, currently those using 64 or 56 bit encryption algorithms
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but excluding export cipher suites.
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Low strength encryption cipher suites, currently those using 64 or 56 bit
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encryption algorithms but excluding export cipher suites.
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As of OpenSSL 1.0.1s, these are disabled in default builds.
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=item B<EXP>, B<EXPORT>
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export encryption algorithms. Including 40 and 56 bits algorithms.
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Export strength encryption algorithms. Including 40 and 56 bits algorithms.
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As of OpenSSL 1.0.1s, these are disabled in default builds.
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=item B<EXPORT40>
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40 bit export encryption algorithms
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40-bit export encryption algorithms
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As of OpenSSL 1.0.1s, these are disabled in default builds.
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=item B<EXPORT56>
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56 bit export encryption algorithms. In OpenSSL 0.9.8c and later the set of
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56-bit export encryption algorithms. In OpenSSL 0.9.8c and later the set of
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56 bit export ciphers is empty unless OpenSSL has been explicitly configured
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with support for experimental ciphers.
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As of OpenSSL 1.0.1s, these are disabled in default builds.
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=item B<eNULL>, B<NULL>
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the "NULL" ciphers that is those offering no encryption. Because these offer no
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encryption at all and are a security risk they are disabled unless explicitly
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included.
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The "NULL" ciphers that is those offering no encryption. Because these offer no
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encryption at all and are a security risk they are not enabled via either the
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B<DEFAULT> or B<ALL> cipher strings.
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Be careful when building cipherlists out of lower-level primitives such as
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B<kRSA> or B<aECDSA> as these do overlap with the B<eNULL> ciphers.
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When in doubt, include B<!eNULL> in your cipherlist.
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=item B<aNULL>
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the cipher suites offering no authentication. This is currently the anonymous
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The cipher suites offering no authentication. This is currently the anonymous
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DH algorithms and anonymous ECDH algorithms. These cipher suites are vulnerable
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to a "man in the middle" attack and so their use is normally discouraged.
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These are excluded from the B<DEFAULT> ciphers, but included in the B<ALL>
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ciphers.
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Be careful when building cipherlists out of lower-level primitives such as
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B<kDHE> or B<AES> as these do overlap with the B<aNULL> ciphers.
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When in doubt, include B<!aNULL> in your cipherlist.
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=item B<kRSA>, B<RSA>
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