Don't set need_record_splitting until aead_write_ctx is set.
setup_key_block is called when the first CCS resolves, but for resumptions this
is the incoming CCS (see ssl3_do_change_cipher_spec). Rather than set
need_record_splitting there, it should be set in the write case of
tls1_change_cipher_state.
This fixes a crash from the new record layer code in resumption when
record-splitting is enabled. Tweak the record-splitting tests to cover this
case.
This also fixes a bug where renego from a cipher which does require record
splitting to one which doesn't continues splitting. Since version switches are
not allowed, this can only happen after a renego from CBC to RC4.
Change-Id: Ie4e1b91282b10f13887b51d1199f76be4fbf09ad
Reviewed-on: https://boringssl-review.googlesource.com/5787
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/t1_enc.c b/ssl/t1_enc.c
index aa6095d..b14f32a 100644
--- a/ssl/t1_enc.c
+++ b/ssl/t1_enc.c
@@ -349,14 +349,26 @@
s->s3->tmp.new_cipher, key, key_len, mac_secret, mac_secret_len, iv,
iv_len);
return s->aead_read_ctx != NULL;
- } else {
- SSL_AEAD_CTX_free(s->aead_write_ctx);
- s->aead_write_ctx = SSL_AEAD_CTX_new(
- evp_aead_seal, ssl3_version_from_wire(s, s->version),
- s->s3->tmp.new_cipher, key, key_len, mac_secret, mac_secret_len, iv,
- iv_len);
- return s->aead_write_ctx != NULL;
}
+
+ SSL_AEAD_CTX_free(s->aead_write_ctx);
+ s->aead_write_ctx = SSL_AEAD_CTX_new(
+ evp_aead_seal, ssl3_version_from_wire(s, s->version),
+ s->s3->tmp.new_cipher, key, key_len, mac_secret, mac_secret_len, iv,
+ iv_len);
+ if (s->aead_write_ctx == NULL) {
+ return 0;
+ }
+
+ s->s3->need_record_splitting = 0;
+ if (!SSL_USE_EXPLICIT_IV(s) &&
+ (s->mode & SSL_MODE_CBC_RECORD_SPLITTING) != 0 &&
+ s->s3->tmp.new_cipher->algorithm_enc != SSL_RC4) {
+ /* Enable 1/n-1 record-splitting to randomize the IV. See
+ * https://www.openssl.org/~bodo/tls-cbc.txt and the BEAST attack. */
+ s->s3->need_record_splitting = 1;
+ }
+ return 1;
}
int tls1_setup_key_block(SSL *s) {
@@ -426,18 +438,6 @@
goto err;
}
- if (!SSL_USE_EXPLICIT_IV(s) &&
- (s->mode & SSL_MODE_CBC_RECORD_SPLITTING) != 0) {
- /* enable vulnerability countermeasure for CBC ciphers with known-IV
- * problem (http://www.openssl.org/~bodo/tls-cbc.txt). */
- s->s3->need_record_splitting = 1;
-
- if (s->session->cipher != NULL &&
- s->session->cipher->algorithm_enc == SSL_RC4) {
- s->s3->need_record_splitting = 0;
- }
- }
-
ret = 1;
err:
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index 51ba563..6284ef6 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -2161,7 +2161,8 @@
MinVersion: VersionTLS10,
CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA},
},
- messageLen: -1, // read until EOF
+ messageLen: -1, // read until EOF
+ resumeSession: true,
flags: []string{
"-async",
"-write-different-record-sizes",
