[TEST-ONLY] Mess with internal logic to test epoch data

This rotates/invalidates keys extremely quickly and also jumps forward
1-8 keys instead of always one to test that part of the logic.

Change-Id: I7cdf992eb6031315c4978c6a1fbbecfa723fca91
Signed-off-by: Arne Schwabe <[email protected]>

Author: schwabe

src/openvpn/crypto.c

@@ -352,6 +352,9 @@ openvpn_encrypt(struct buffer *buf, struct buffer work,
 int64_t
 cipher_get_aead_limits(const char *ciphername)
 {
+    /* TESTING: Make AEAD key limits really really really small to force
+     * key rollever super quickly */
+    return 256;
     if (!cipher_kt_mode_aead(ciphername))
     {
         return 0;

src/openvpn/crypto_epoch.c

@@ -414,8 +414,13 @@ epoch_check_send_iterate(struct crypto_options *opt)
         if (aead_usage_limit_reached(opt->aead_usage_limit, &opt->key_ctx_bi.encrypt,
                                      opt->packet_id.send.id))
         {
-            /* Send key limit reached */
-            epoch_iterate_send_key(opt);
+            int forward = rand() % 8 + 1;
+            /* Send key limit reached, go one key forward or in this TEST
+             * gremlin mode, 1 to 8 to test the other side future key stuff */
+            for (int i = 0; i < forward; i++)
+            {
+                epoch_iterate_send_key(opt);
+            }
         }
         /* draft 8 of the aead usage limit still had but draft 9 complete
          * dropped this statement:
@@ -437,7 +442,13 @@ epoch_check_send_iterate(struct crypto_options *opt)
             /* Receive key limit reached. Increase our own send key to signal
              * that we want to use a new epoch. Peer should then also move its
              * key but is not required to do this */
-            epoch_iterate_send_key(opt);
+            int forward = rand() % 8 + 1;
+            /* gremlin mode, 1 to 8 to test the other side future key stuff */
+            for (int i = 0; i < forward; i++)
+            {
+                epoch_iterate_send_key(opt);
+            }
+
         }
     }
 

tests/unit_tests/openvpn/test_ssl.c

@@ -398,7 +398,7 @@ init_crypto_options(const char *cipher, const char *auth, bool epoch,
         struct epoch_key e1 = { .epoch = 1, .epoch_key = { 0 }};
         memcpy(e1.epoch_key, key2.keys[0].cipher, sizeof(e1.epoch_key));
         co.flags |= CO_EPOCH_DATA_KEY_FORMAT;
-        epoch_init_key_ctx(&co, &kt, &e1, &e1, 5);
+        epoch_init_key_ctx(&co, &kt, &e1, &e1, 9);
 
         /* Do a little of dancing for the epoch_send_key_iterate to test
          * that this works too */