Commit a556f342 authored by Emilia Kasper's avatar Emilia Kasper
Browse files

Rework the default cipherlist. 



 - Always prefer forward-secure handshakes.
 - Consistently order ECDSA above RSA.
 - Next, always prefer AEADs to non-AEADs, irrespective of strength.
 - Within AEADs, prefer GCM > CHACHA > CCM for a given strength.
 - Prefer TLS v1.2 ciphers to legacy ciphers.
 - Remove rarely used DSS, IDEA, SEED, CAMELLIA, CCM from the default
   list to reduce ClientHello bloat.

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
parent 3ed1839d

CHANGES

+9 −0
Original line number Diff line number Diff line
@@ -4,6 +4,15 @@ 


 Changes between 1.0.2g and 1.1.0  [xx XXX xxxx]



  *) Changes to the DEFAULT cipherlist:

       - Prefer (EC)DHE handshakes over plain RSA.

       - Prefer AEAD ciphers over legacy ciphers.

       - Prefer ECDSA over RSA when both certificates are available.

       - Prefer TLSv1.2 ciphers/PRF.

       - Remove DSS, SEED, IDEA, CAMELLIA, and AES-CCM from the

         default cipherlist.

     [Emilia Käsper]



  *) Change the ECC default curve list to be this, in order: x25519,

     secp256r1, secp521r1, secp384r1.

     [Rich Salz]

ssl/s3_lib.c

+58 −58
Original line number Diff line number Diff line
@@ -239,7 +239,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_IDEA,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_MEDIUM,

     SSL_NOT_DEFAULT | SSL_MEDIUM,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -272,7 +272,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_3DES,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     112,

     168,
@@ -401,7 +401,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -463,7 +463,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     256,

     256,
@@ -560,7 +560,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -579,7 +579,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -595,7 +595,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -611,7 +611,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -661,7 +661,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     256,

     256,
@@ -759,7 +759,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     256,

     256,
@@ -775,7 +775,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     256,

     256,
@@ -791,7 +791,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     256,

     256,
@@ -1028,7 +1028,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_SEED,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_MEDIUM,

     SSL_NOT_DEFAULT | SSL_MEDIUM,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -1044,7 +1044,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_SEED,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_MEDIUM,

     SSL_NOT_DEFAULT | SSL_MEDIUM,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -1060,7 +1060,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_SEED,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_MEDIUM,

     SSL_NOT_DEFAULT | SSL_MEDIUM,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -1160,7 +1160,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128GCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -1176,7 +1176,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256GCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH | SSL_FIPS,

     SSL_NOT_DEFAULT | SSL_HIGH | SSL_FIPS,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256,
@@ -1518,7 +1518,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -1534,7 +1534,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -1550,7 +1550,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -1582,7 +1582,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -1598,7 +1598,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -1614,7 +1614,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -1929,7 +1929,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_3DES,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     112,

     168,
@@ -1977,7 +1977,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128,
@@ -2025,7 +2025,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256,

     SSL_SHA1,

     SSL_SSLV3,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     256,

     256,
@@ -2323,7 +2323,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128},
@@ -2337,7 +2337,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA384,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256},
@@ -2351,7 +2351,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128},
@@ -2365,7 +2365,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA384,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256},
@@ -2383,7 +2383,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128},
@@ -2397,7 +2397,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA384,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256},
@@ -2411,7 +2411,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128},
@@ -2425,7 +2425,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA384,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256},
@@ -2439,7 +2439,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128},
@@ -2453,7 +2453,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA384,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256},
@@ -2467,7 +2467,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA128,

     SSL_SHA256,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_DEFAULT | TLS1_PRF,

     128,

     128},
@@ -2481,7 +2481,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_CAMELLIA256,

     SSL_SHA384,

     SSL_TLSV1,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA384 | TLS1_PRF_SHA384,

     256,

     256},
@@ -2497,7 +2497,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2513,7 +2513,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2529,7 +2529,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2545,7 +2545,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2561,7 +2561,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2577,7 +2577,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2593,7 +2593,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2609,7 +2609,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2625,7 +2625,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2641,7 +2641,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2657,7 +2657,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2673,7 +2673,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2689,7 +2689,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2705,7 +2705,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2721,7 +2721,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2737,7 +2737,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2753,7 +2753,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2769,7 +2769,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,
@@ -2785,7 +2785,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES128CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     128,

     128,
@@ -2801,7 +2801,7 @@ static const SSL_CIPHER ssl3_ciphers[] = { 
     SSL_AES256CCM8,

     SSL_AEAD,

     SSL_TLSV1_2,

     SSL_HIGH,

     SSL_NOT_DEFAULT | SSL_HIGH,

     SSL_HANDSHAKE_MAC_SHA256 | TLS1_PRF_SHA256,

     256,

     256,

ssl/ssl_ciph.c

+57 −6
Original line number Diff line number Diff line
@@ -278,6 +278,11 @@ static int ssl_mac_secret_size[SSL_MD_NUM_IDX] = { 
#define CIPHER_DEL      3

#define CIPHER_ORD      4

#define CIPHER_SPECIAL  5

/*

 * Bump the ciphers to the top of the list.

 * This rule isn't currently supported by the public cipherstring API.

 */

#define CIPHER_BUMP     6



typedef struct cipher_order_st {

    const SSL_CIPHER *cipher;
@@ -896,7 +901,7 @@ static void ssl_cipher_apply_rule(uint32_t cipher_id, uint32_t alg_mkey, 
            algo_strength, strength_bits);

#endif



    if (rule == CIPHER_DEL)

    if (rule == CIPHER_DEL || rule == CIPHER_BUMP)

        reverse = 1;            /* needed to maintain sorting between

                                 * currently deleted ciphers */
@@ -986,6 +991,9 @@ static void ssl_cipher_apply_rule(uint32_t cipher_id, uint32_t alg_mkey, 
                ll_append_head(&head, curr, &tail);

                curr->active = 0;

            }

        } else if (rule == CIPHER_BUMP) {

            if (curr->active)

                ll_append_head(&head, curr, &tail);

        } else if (rule == CIPHER_KILL) {

            /* reverse == 0 */

            if (head == curr)
@@ -1420,20 +1428,36 @@ STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method, STACK 
                               disabled_mac, disabled_ssl, co_list, &head,

                               &tail);



    /* Now arrange all ciphers by preference: */

    /* Now arrange all ciphers by preference. */



    /*

     * Everything else being equal, prefer ephemeral ECDH over other key

     * exchange mechanisms

     * exchange mechanisms.

     * For consistency, prefer ECDSA over RSA (though this only matters if the

     * server has both certificates, and is using the DEFAULT, or a client

     * preference).

     */

    ssl_cipher_apply_rule(0, SSL_kECDHE, SSL_aECDSA, 0, 0, 0, 0, CIPHER_ADD,

                          -1, &head, &tail);

    ssl_cipher_apply_rule(0, SSL_kECDHE, 0, 0, 0, 0, 0, CIPHER_ADD, -1, &head,

                          &tail);

    ssl_cipher_apply_rule(0, SSL_kECDHE, 0, 0, 0, 0, 0, CIPHER_DEL, -1, &head,

                          &tail);



    /* AES is our preferred symmetric cipher */

    ssl_cipher_apply_rule(0, 0, 0, SSL_AES, 0, 0, 0, CIPHER_ADD, -1, &head,

                          &tail);



    /* Within each strength group, we prefer GCM over CHACHA... */

    ssl_cipher_apply_rule(0, 0, 0, SSL_AESGCM, 0, 0, 0, CIPHER_ADD, -1,

                          &head, &tail);

    ssl_cipher_apply_rule(0, 0, 0, SSL_CHACHA20, 0, 0, 0, CIPHER_ADD, -1,

                          &head, &tail);



     /*

      * ...and generally, our preferred cipher is AES.

      * Note that AEADs will be bumped to take preference after sorting by

      * strength.

      */

    ssl_cipher_apply_rule(0, 0, 0, SSL_AES ^ SSL_AESGCM, 0, 0, 0, CIPHER_ADD,

                          -1, &head, &tail);



    /* Temporarily enable everything else for sorting */

    ssl_cipher_apply_rule(0, 0, 0, 0, 0, 0, 0, CIPHER_ADD, -1, &head, &tail);
@@ -1472,6 +1496,33 @@ STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method, STACK 
        return NULL;

    }



    /*

     * Partially overrule strength sort to prefer TLS 1.2 ciphers/PRFs.

     * TODO(openssl-team): is there an easier way to accomplish all this?

     */

    ssl_cipher_apply_rule(0, 0, 0, 0, 0, SSL_TLSV1_2, 0, CIPHER_BUMP, -1,

                          &head, &tail);



    /*

     * Irrespective of strength, enforce the following order:

     * (EC)DHE + AEAD > (EC)DHE > rest of AEAD > rest.

     * Within each group, ciphers remain sorted by strength and previous

     * preference, i.e.,

     * 1) ECDHE > DHE

     * 2) GCM > CHACHA

     * 3) AES > rest

     * 4) TLS 1.2 > legacy

     *

     * Because we now bump ciphers to the top of the list, we proceed in

     * reverse order of preference.

     */

    ssl_cipher_apply_rule(0, 0, 0, 0, SSL_AEAD, 0, 0, CIPHER_BUMP, -1,

                          &head, &tail);

    ssl_cipher_apply_rule(0, SSL_kDHE | SSL_kECDHE, 0, 0, 0, 0, 0,

                          CIPHER_BUMP, -1,  &head, &tail);

    ssl_cipher_apply_rule(0, SSL_kDHE | SSL_kECDHE, 0, 0, SSL_AEAD, 0, 0,

                          CIPHER_BUMP, -1,  &head, &tail);



    /* Now disable everything (maintaining the ordering!) */

    ssl_cipher_apply_rule(0, 0, 0, 0, 0, 0, 0, CIPHER_DEL, -1, &head, &tail);

ssl/ssl_locl.h

+3 −1
Original line number Diff line number Diff line
@@ -358,7 +358,9 @@ 
# define SSL_eGOST2814789CNT12   0x00040000U

# define SSL_CHACHA20POLY1305    0x00080000U



# define SSL_AES                 (SSL_AES128|SSL_AES256|SSL_AES128GCM|SSL_AES256GCM|SSL_AES128CCM|SSL_AES256CCM|SSL_AES128CCM8|SSL_AES256CCM8)

# define SSL_AESGCM              (SSL_AES128GCM | SSL_AES256GCM)

# define SSL_AESCCM              (SSL_AES128CCM | SSL_AES256CCM | SSL_AES128CCM8 | SSL_AES256CCM8)

# define SSL_AES                 (SSL_AES128|SSL_AES256|SSL_AESGCM|SSL_AESCCM)

# define SSL_CAMELLIA            (SSL_CAMELLIA128|SSL_CAMELLIA256)

# define SSL_CHACHA20            (SSL_CHACHA20POLY1305)