1 files changed, 167 insertions, 0 deletions
diff --git a/chromium/net/quic/crypto/aead_base_decrypter.cc b/chromium/net/quic/crypto/aead_base_decrypter.cc
new file mode 100644
index 00000000000..8b6661a9ba9
--- /dev/null
+++ b/chromium/net/quic/crypto/aead_base_decrypter.cc
@@ -0,0 +1,167 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <openssl/err.h>
+#include <openssl/evp.h>
+
+#include <memory>
+
+#include "net/quic/crypto/aead_base_decrypter.h"
+#include "net/quic/quic_bug_tracker.h"
+#include "net/quic/quic_flags.h"
+#include "net/quic/quic_utils.h"
+
+using base::StringPiece;
+using std::string;
+
+namespace net {
+
+namespace {
+
+// Clear OpenSSL error stack.
+void ClearOpenSslErrors() {
+  while (ERR_get_error()) {
+  }
+}
+
+// In debug builds only, log OpenSSL error stack. Then clear OpenSSL error
+// stack.
+void DLogOpenSslErrors() {
+#ifdef NDEBUG
+  ClearOpenSslErrors();
+#else
+  while (uint32_t error = ERR_get_error()) {
+    char buf[120];
+    ERR_error_string_n(error, buf, arraysize(buf));
+    DLOG(ERROR) << "OpenSSL error: " << buf;
+  }
+#endif
+}
+
+}  // namespace
+
+AeadBaseDecrypter::AeadBaseDecrypter(const EVP_AEAD* aead_alg,
+                                     size_t key_size,
+                                     size_t auth_tag_size,
+                                     size_t nonce_prefix_size)
+    : aead_alg_(aead_alg),
+      key_size_(key_size),
+      auth_tag_size_(auth_tag_size),
+      nonce_prefix_size_(nonce_prefix_size),
+      have_preliminary_key_(false) {
+  DCHECK_GT(256u, key_size);
+  DCHECK_GT(256u, auth_tag_size);
+  DCHECK_GT(256u, nonce_prefix_size);
+  DCHECK_LE(key_size_, sizeof(key_));
+  DCHECK_LE(nonce_prefix_size_, sizeof(nonce_prefix_));
+}
+
+AeadBaseDecrypter::~AeadBaseDecrypter() {}
+
+bool AeadBaseDecrypter::SetKey(StringPiece key) {
+  DCHECK_EQ(key.size(), key_size_);
+  if (key.size() != key_size_) {
+    return false;
+  }
+  memcpy(key_, key.data(), key.size());
+
+  EVP_AEAD_CTX_cleanup(ctx_.get());
+  if (!EVP_AEAD_CTX_init(ctx_.get(), aead_alg_, key_, key_size_, auth_tag_size_,
+                         nullptr)) {
+    DLogOpenSslErrors();
+    return false;
+  }
+
+  return true;
+}
+
+bool AeadBaseDecrypter::SetNoncePrefix(StringPiece nonce_prefix) {
+  DCHECK_EQ(nonce_prefix.size(), nonce_prefix_size_);
+  if (nonce_prefix.size() != nonce_prefix_size_) {
+    return false;
+  }
+  memcpy(nonce_prefix_, nonce_prefix.data(), nonce_prefix.size());
+  return true;
+}
+
+bool AeadBaseDecrypter::SetPreliminaryKey(StringPiece key) {
+  DCHECK(!have_preliminary_key_);
+  SetKey(key);
+  have_preliminary_key_ = true;
+
+  return true;
+}
+
+bool AeadBaseDecrypter::SetDiversificationNonce(DiversificationNonce nonce) {
+  if (!have_preliminary_key_) {
+    return true;
+  }
+
+  string key, nonce_prefix;
+  DiversifyPreliminaryKey(
+      StringPiece(reinterpret_cast<const char*>(key_), key_size_),
+      StringPiece(reinterpret_cast<const char*>(nonce_prefix_),
+                  nonce_prefix_size_),
+      nonce, key_size_, nonce_prefix_size_, &key, &nonce_prefix);
+
+  if (!SetKey(key) || !SetNoncePrefix(nonce_prefix)) {
+    DCHECK(false);
+    return false;
+  }
+
+  have_preliminary_key_ = false;
+  return true;
+}
+
+bool AeadBaseDecrypter::DecryptPacket(QuicPathId path_id,
+                                      QuicPacketNumber packet_number,
+                                      StringPiece associated_data,
+                                      StringPiece ciphertext,
+                                      char* output,
+                                      size_t* output_length,
+                                      size_t max_output_length) {
+  if (ciphertext.length() < auth_tag_size_) {
+    return false;
+  }
+
+  if (have_preliminary_key_) {
+    QUIC_BUG << "Unable to decrypt while key diversification is pending";
+    return false;
+  }
+
+  uint8_t nonce[sizeof(nonce_prefix_) + sizeof(packet_number)];
+  const size_t nonce_size = nonce_prefix_size_ + sizeof(packet_number);
+  memcpy(nonce, nonce_prefix_, nonce_prefix_size_);
+  uint64_t path_id_packet_number =
+      QuicUtils::PackPathIdAndPacketNumber(path_id, packet_number);
+  memcpy(nonce + nonce_prefix_size_, &path_id_packet_number,
+         sizeof(path_id_packet_number));
+  if (!EVP_AEAD_CTX_open(
+          ctx_.get(), reinterpret_cast<uint8_t*>(output), output_length,
+          max_output_length, reinterpret_cast<const uint8_t*>(nonce),
+          nonce_size, reinterpret_cast<const uint8_t*>(ciphertext.data()),
+          ciphertext.size(),
+          reinterpret_cast<const uint8_t*>(associated_data.data()),
+          associated_data.size())) {
+    // Because QuicFramer does trial decryption, decryption errors are expected
+    // when encryption level changes. So we don't log decryption errors.
+    ClearOpenSslErrors();
+    return false;
+  }
+  return true;
+}
+
+StringPiece AeadBaseDecrypter::GetKey() const {
+  return StringPiece(reinterpret_cast<const char*>(key_), key_size_);
+}
+
+StringPiece AeadBaseDecrypter::GetNoncePrefix() const {
+  if (nonce_prefix_size_ == 0) {
+    return StringPiece();
+  }
+  return StringPiece(reinterpret_cast<const char*>(nonce_prefix_),
+                     nonce_prefix_size_);
+}
+
+}  // namespace net