commit fbc45d7228de54e227d61dcc60ee49ef0dfea4e8
author David Benjamin <davidben@google.com> Thu Sep 22 01:21:24 2016 -0400
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> Thu Sep 22 21:26:23 2016 +0000
tree 784e356d0597221e5872bc40d8bd28c5b3331a73
parent 1e663e8f396e26025309553459bc334e2d21fd0e

No-op ticket encryption in fuzzer mode.

This allows the fuzzer to discover server-side resumption paths by
simply supplying what we'd like the ticket to decrypt to in the clear.
We also have a natural way to get transcripts out of runner. We record
the runner-side transcripts, so all resumption handshakes will replay
the shim-created unencrypted tickets.

BUG=104

Change-Id: Icf9cbf4af520077d38e2c8c2766b6f8bfa3c9ab5
Reviewed-on: https://boringssl-review.googlesource.com/11224
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

ssl/t1_lib.c

diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index 81dbdc4..8db132f 100644
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -2963,7 +2963,12 @@
   }
   HMAC_Update(&hmac_ctx, ticket, ticket_len - mac_len);
   HMAC_Final(&hmac_ctx, mac, NULL);
-  if (CRYPTO_memcmp(mac, ticket + (ticket_len - mac_len), mac_len) != 0) {
+  int mac_ok =
+      CRYPTO_memcmp(mac, ticket + (ticket_len - mac_len), mac_len) == 0;
+#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
+  mac_ok = 1;
+#endif
+  if (!mac_ok) {
     goto done;
   }
 
@@ -2976,6 +2981,11 @@
     ret = 0;
     goto done;
   }
+  size_t plaintext_len;
+#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
+  memcpy(plaintext, ciphertext, ciphertext_len);
+  plaintext_len = ciphertext_len;
+#else
   if (ciphertext_len >= INT_MAX) {
     goto done;
   }
@@ -2986,9 +2996,11 @@
     ERR_clear_error(); /* Don't leave an error on the queue. */
     goto done;
   }
+  plaintext_len = (size_t)(len1 + len2);
+#endif
 
   /* Decode the session. */
-  SSL_SESSION *session = SSL_SESSION_from_bytes(plaintext, len1 + len2);
+  SSL_SESSION *session = SSL_SESSION_from_bytes(plaintext, plaintext_len);
   if (session == NULL) {
     ERR_clear_error(); /* Don't leave an error on the queue. */
     goto done;