update master-with-bazel from master branch

src/ssl/d1_lib.cc

@@ -95,8 +95,14 @@ bool dtls1_new(SSL *ssl) {
     return false;
   }
 
-  d1->initial_aead_write_ctx = SSLAEADContext::CreateNullCipher(true);
-  if (!d1->initial_aead_write_ctx) {
+  d1->initial_epoch_state = MakeUnique<DTLSEpochState>();
+  if (!d1->initial_epoch_state) {
+    tls_free(ssl);
+    return false;
+  }
+  d1->initial_epoch_state->aead_write_ctx =
+      SSLAEADContext::CreateNullCipher(true);
+  if (!d1->initial_epoch_state->aead_write_ctx) {
     tls_free(ssl);
     return false;
   }

src/ssl/dtls_method.cc

@@ -112,13 +112,13 @@ static bool dtls1_set_write_state(SSL *ssl, ssl_encryption_level_t level,
                                   Span<const uint8_t> secret_for_quic) {
   assert(secret_for_quic.empty());  // QUIC does not use DTLS.
   ssl->d1->w_epoch++;
-  ssl->d1->last_write_sequence = ssl->s3->write_sequence;
   ssl->s3->write_sequence = 0;
 
   if (ssl_protocol_version(ssl) > TLS1_2_VERSION) {
     ssl->d1->w_epoch = level;
   }
-  ssl->d1->last_aead_write_ctx = std::move(ssl->s3->aead_write_ctx);
+  ssl->d1->last_epoch_state.aead_write_ctx = std::move(ssl->s3->aead_write_ctx);
+  ssl->d1->last_epoch_state.write_sequence = ssl->s3->write_sequence;
   ssl->s3->aead_write_ctx = std::move(aead_ctx);
   ssl->s3->write_level = level;
   return true;

src/ssl/dtls_record.cc

@@ -417,12 +417,12 @@ enum ssl_open_record_t dtls_open_record(SSL *ssl, uint8_t *out_type,
 
 static SSLAEADContext *get_write_aead(const SSL *ssl, uint16_t epoch) {
   if (epoch == 0) {
-    return ssl->d1->initial_aead_write_ctx.get();
+    return ssl->d1->initial_epoch_state->aead_write_ctx.get();
   }
 
   if (epoch < ssl->d1->w_epoch) {
     BSSL_CHECK(epoch + 1 == ssl->d1->w_epoch);
-    return ssl->d1->last_aead_write_ctx.get();
+    return ssl->d1->last_epoch_state.aead_write_ctx.get();
   }
 
   BSSL_CHECK(epoch == ssl->d1->w_epoch);
@@ -477,11 +477,11 @@ bool dtls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
   // Determine the parameters for the current epoch.
   SSLAEADContext *aead = get_write_aead(ssl, epoch);
   uint64_t *seq = &ssl->s3->write_sequence;
-  if (epoch < ssl->d1->w_epoch) {
-    seq = &ssl->d1->last_write_sequence;
+  if (epoch == 0) {
+    seq = &ssl->d1->initial_epoch_state->write_sequence;
+  } else if (epoch < ssl->d1->w_epoch) {
+    seq = &ssl->d1->last_epoch_state.write_sequence;
   }
-  // TODO(crbug.com/boringssl/715): If epoch is initial or handshake, the value
-  // of seq is probably wrong for a retransmission.
 
   const size_t record_header_len = dtls_record_header_write_len(ssl, epoch);
 

src/ssl/internal.h

@@ -3072,6 +3072,14 @@ struct OPENSSL_timeval {
   uint32_t tv_usec;
 };
 
+// A DTLSEpochState object contains state about a DTLS epoch.
+struct DTLSEpochState {
+  static constexpr bool kAllowUniquePtr = true;
+
+  UniquePtr<SSLAEADContext> aead_write_ctx;
+  uint64_t write_sequence;
+};
+
 struct DTLS1_STATE {
   static constexpr bool kAllowUniquePtr = true;
 
@@ -3103,14 +3111,12 @@ struct DTLS1_STATE {
   uint16_t handshake_write_seq = 0;
   uint16_t handshake_read_seq = 0;
 
-  // save last sequence number for retransmissions
-  uint64_t last_write_sequence = 0;
-  UniquePtr<SSLAEADContext> last_aead_write_ctx;
-
+  // state from the last epoch
+  DTLSEpochState last_epoch_state;
 
   // In DTLS 1.3, this contains the write AEAD for the initial encryption level.
   // TODO(crbug.com/boringssl/715): Drop this when it is no longer needed.
-  UniquePtr<SSLAEADContext> initial_aead_write_ctx;
+  UniquePtr<DTLSEpochState> initial_epoch_state;
 
   // incoming_messages is a ring buffer of incoming handshake messages that have
   // yet to be processed. The front of the ring buffer is message number