Add net/quic/crypto/crypto_handshake_message.{cc,h}.

These files are part of https://codereview.chromium.org/147763009/.
They are added first so that the rest of that CL can be committed by
the commit queue.

TBR=rch@chromium.org
BUG=none
TEST=none

Review URL: https://codereview.chromium.org/154643006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248826 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 448 insertions, 0 deletions

diff --git a/net/quic/crypto/crypto_handshake_message.cc b/net/quic/crypto/crypto_handshake_message.cc
new file mode 100644
index 0000000..7efa0b5
--- /dev/null
+++ b/net/quic/crypto/crypto_handshake_message.cc
@@ -0,0 +1,313 @@
+// 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 "net/quic/crypto/crypto_handshake_message.h"
+
+#include "base/strings/stringprintf.h"
+#include "base/strings/string_number_conversions.h"
+#include "net/quic/crypto/crypto_framer.h"
+#include "net/quic/crypto/crypto_protocol.h"
+#include "net/quic/quic_utils.h"
+
+using base::StringPiece;
+using base::StringPrintf;
+using std::string;
+using std::vector;
+
+namespace net {
+
+CryptoHandshakeMessage::CryptoHandshakeMessage()
+    : tag_(0),
+      minimum_size_(0) {}
+
+CryptoHandshakeMessage::CryptoHandshakeMessage(
+    const CryptoHandshakeMessage& other)
+    : tag_(other.tag_),
+      tag_value_map_(other.tag_value_map_),
+      minimum_size_(other.minimum_size_) {
+  // Don't copy serialized_. scoped_ptr doesn't have a copy constructor.
+  // The new object can lazily reconstruct serialized_.
+}
+
+CryptoHandshakeMessage::~CryptoHandshakeMessage() {}
+
+CryptoHandshakeMessage& CryptoHandshakeMessage::operator=(
+    const CryptoHandshakeMessage& other) {
+  tag_ = other.tag_;
+  tag_value_map_ = other.tag_value_map_;
+  // Don't copy serialized_. scoped_ptr doesn't have an assignment operator.
+  // However, invalidate serialized_.
+  serialized_.reset();
+  minimum_size_ = other.minimum_size_;
+  return *this;
+}
+
+void CryptoHandshakeMessage::Clear() {
+  tag_ = 0;
+  tag_value_map_.clear();
+  minimum_size_ = 0;
+  serialized_.reset();
+}
+
+const QuicData& CryptoHandshakeMessage::GetSerialized() const {
+  if (!serialized_.get()) {
+    serialized_.reset(CryptoFramer::ConstructHandshakeMessage(*this));
+  }
+  return *serialized_.get();
+}
+
+void CryptoHandshakeMessage::MarkDirty() {
+  serialized_.reset();
+}
+
+void CryptoHandshakeMessage::SetTaglist(QuicTag tag, ...) {
+  // Warning, if sizeof(QuicTag) > sizeof(int) then this function will break
+  // because the terminating 0 will only be promoted to int.
+  COMPILE_ASSERT(sizeof(QuicTag) <= sizeof(int),
+                 crypto_tag_may_not_be_larger_than_int_or_varargs_will_break);
+
+  vector<QuicTag> tags;
+  va_list ap;
+
+  va_start(ap, tag);
+  for (;;) {
+    QuicTag list_item = va_arg(ap, QuicTag);
+    if (list_item == 0) {
+      break;
+    }
+    tags.push_back(list_item);
+  }
+
+  // Because of the way that we keep tags in memory, we can copy the contents
+  // of the vector and get the correct bytes in wire format. See
+  // crypto_protocol.h. This assumes that the system is little-endian.
+  SetVector(tag, tags);
+
+  va_end(ap);
+}
+
+void CryptoHandshakeMessage::SetStringPiece(QuicTag tag, StringPiece value) {
+  tag_value_map_[tag] = value.as_string();
+}
+
+void CryptoHandshakeMessage::Erase(QuicTag tag) {
+  tag_value_map_.erase(tag);
+}
+
+QuicErrorCode CryptoHandshakeMessage::GetTaglist(QuicTag tag,
+                                                 const QuicTag** out_tags,
+                                                 size_t* out_len) const {
+  QuicTagValueMap::const_iterator it = tag_value_map_.find(tag);
+  QuicErrorCode ret = QUIC_NO_ERROR;
+
+  if (it == tag_value_map_.end()) {
+    ret = QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
+  } else if (it->second.size() % sizeof(QuicTag) != 0) {
+    ret = QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
+  }
+
+  if (ret != QUIC_NO_ERROR) {
+    *out_tags = NULL;
+    *out_len = 0;
+    return ret;
+  }
+
+  *out_tags = reinterpret_cast<const QuicTag*>(it->second.data());
+  *out_len = it->second.size() / sizeof(QuicTag);
+  return ret;
+}
+
+bool CryptoHandshakeMessage::GetStringPiece(QuicTag tag,
+                                            StringPiece* out) const {
+  QuicTagValueMap::const_iterator it = tag_value_map_.find(tag);
+  if (it == tag_value_map_.end()) {
+    return false;
+  }
+  *out = it->second;
+  return true;
+}
+
+QuicErrorCode CryptoHandshakeMessage::GetNthValue24(QuicTag tag,
+                                                    unsigned index,
+                                                    StringPiece* out) const {
+  StringPiece value;
+  if (!GetStringPiece(tag, &value)) {
+    return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
+  }
+
+  for (unsigned i = 0;; i++) {
+    if (value.empty()) {
+      return QUIC_CRYPTO_MESSAGE_INDEX_NOT_FOUND;
+    }
+    if (value.size() < 3) {
+      return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
+    }
+
+    const unsigned char* data =
+        reinterpret_cast<const unsigned char*>(value.data());
+    size_t size = static_cast<size_t>(data[0]) |
+                  (static_cast<size_t>(data[1]) << 8) |
+                  (static_cast<size_t>(data[2]) << 16);
+    value.remove_prefix(3);
+
+    if (value.size() < size) {
+      return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
+    }
+
+    if (i == index) {
+      *out = StringPiece(value.data(), size);
+      return QUIC_NO_ERROR;
+    }
+
+    value.remove_prefix(size);
+  }
+}
+
+QuicErrorCode CryptoHandshakeMessage::GetUint16(QuicTag tag,
+                                                uint16* out) const {
+  return GetPOD(tag, out, sizeof(uint16));
+}
+
+QuicErrorCode CryptoHandshakeMessage::GetUint32(QuicTag tag,
+                                                uint32* out) const {
+  return GetPOD(tag, out, sizeof(uint32));
+}
+
+QuicErrorCode CryptoHandshakeMessage::GetUint64(QuicTag tag,
+                                                uint64* out) const {
+  return GetPOD(tag, out, sizeof(uint64));
+}
+
+size_t CryptoHandshakeMessage::size() const {
+  size_t ret = sizeof(QuicTag) +
+               sizeof(uint16) /* number of entries */ +
+               sizeof(uint16) /* padding */;
+  ret += (sizeof(QuicTag) + sizeof(uint32) /* end offset */) *
+         tag_value_map_.size();
+  for (QuicTagValueMap::const_iterator i = tag_value_map_.begin();
+       i != tag_value_map_.end(); ++i) {
+    ret += i->second.size();
+  }
+
+  return ret;
+}
+
+void CryptoHandshakeMessage::set_minimum_size(size_t min_bytes) {
+  if (min_bytes == minimum_size_) {
+    return;
+  }
+  serialized_.reset();
+  minimum_size_ = min_bytes;
+}
+
+size_t CryptoHandshakeMessage::minimum_size() const {
+  return minimum_size_;
+}
+
+string CryptoHandshakeMessage::DebugString() const {
+  return DebugStringInternal(0);
+}
+
+QuicErrorCode CryptoHandshakeMessage::GetPOD(
+    QuicTag tag, void* out, size_t len) const {
+  QuicTagValueMap::const_iterator it = tag_value_map_.find(tag);
+  QuicErrorCode ret = QUIC_NO_ERROR;
+
+  if (it == tag_value_map_.end()) {
+    ret = QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
+  } else if (it->second.size() != len) {
+    ret = QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
+  }
+
+  if (ret != QUIC_NO_ERROR) {
+    memset(out, 0, len);
+    return ret;
+  }
+
+  memcpy(out, it->second.data(), len);
+  return ret;
+}
+
+string CryptoHandshakeMessage::DebugStringInternal(size_t indent) const {
+  string ret = string(2 * indent, ' ') + QuicUtils::TagToString(tag_) + "<\n";
+  ++indent;
+  for (QuicTagValueMap::const_iterator it = tag_value_map_.begin();
+       it != tag_value_map_.end(); ++it) {
+    ret += string(2 * indent, ' ') + QuicUtils::TagToString(it->first) + ": ";
+
+    bool done = false;
+    switch (it->first) {
+      case kICSL:
+      case kIRTT:
+      case kKATO:
+      case kMSPC:
+      case kSWND:
+        // uint32 value
+        if (it->second.size() == 4) {
+          uint32 value;
+          memcpy(&value, it->second.data(), sizeof(value));
+          ret += base::UintToString(value);
+          done = true;
+        }
+        break;
+      case kVERS:
+        // uint16 value
+        if (it->second.size() == 2) {
+          uint16 value;
+          memcpy(&value, it->second.data(), sizeof(value));
+          ret += base::UintToString(value);
+          done = true;
+        }
+        break;
+      case kKEXS:
+      case kAEAD:
+      case kCGST:
+      case kPDMD:
+      case kVER:
+        // tag lists
+        if (it->second.size() % sizeof(QuicTag) == 0) {
+          for (size_t j = 0; j < it->second.size(); j += sizeof(QuicTag)) {
+            QuicTag tag;
+            memcpy(&tag, it->second.data() + j, sizeof(tag));
+            if (j > 0) {
+              ret += ",";
+            }
+            ret += "'" + QuicUtils::TagToString(tag) + "'";
+          }
+          done = true;
+        }
+        break;
+      case kSCFG:
+        // nested messages.
+        if (!it->second.empty()) {
+          scoped_ptr<CryptoHandshakeMessage> msg(
+              CryptoFramer::ParseMessage(it->second));
+          if (msg.get()) {
+            ret += "\n";
+            ret += msg->DebugStringInternal(indent + 1);
+
+            done = true;
+          }
+        }
+        break;
+      case kPAD:
+        ret += StringPrintf("(%d bytes of padding)",
+                            static_cast<int>(it->second.size()));
+        done = true;
+        break;
+    }
+
+    if (!done) {
+      // If there's no specific format for this tag, or the value is invalid,
+      // then just use hex.
+      ret += "0x" + base::HexEncode(it->second.data(), it->second.size());
+    }
+    ret += "\n";
+  }
+  --indent;
+  ret += string(2 * indent, ' ') + ">";
+  return ret;
+}
+
+}  // namespace net
diff --git a/net/quic/crypto/crypto_handshake_message.h b/net/quic/crypto/crypto_handshake_message.h
new file mode 100644
index 0000000..fcb3930
--- /dev/null
+++ b/net/quic/crypto/crypto_handshake_message.h
@@ -0,0 +1,135 @@
+// 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.
+
+#ifndef NET_QUIC_CRYPTO_CRYPTO_HANDSHAKE_MESSAGE_H_
+#define NET_QUIC_CRYPTO_CRYPTO_HANDSHAKE_MESSAGE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/strings/string_piece.h"
+#include "net/base/net_export.h"
+#include "net/quic/quic_protocol.h"
+
+namespace net {
+
+// An intermediate format of a handshake message that's convenient for a
+// CryptoFramer to serialize from or parse into.
+class NET_EXPORT_PRIVATE CryptoHandshakeMessage {
+ public:
+  CryptoHandshakeMessage();
+  CryptoHandshakeMessage(const CryptoHandshakeMessage& other);
+  ~CryptoHandshakeMessage();
+
+  CryptoHandshakeMessage& operator=(const CryptoHandshakeMessage& other);
+
+  // Clears state.
+  void Clear();
+
+  // GetSerialized returns the serialized form of this message and caches the
+  // result. Subsequently altering the message does not invalidate the cache.
+  const QuicData& GetSerialized() const;
+
+  // MarkDirty invalidates the cache created by |GetSerialized|.
+  void MarkDirty();
+
+  // SetValue sets an element with the given tag to the raw, memory contents of
+  // |v|.
+  template<class T> void SetValue(QuicTag tag, const T& v) {
+    tag_value_map_[tag] =
+        std::string(reinterpret_cast<const char*>(&v), sizeof(v));
+  }
+
+  // SetVector sets an element with the given tag to the raw contents of an
+  // array of elements in |v|.
+  template<class T> void SetVector(QuicTag tag, const std::vector<T>& v) {
+    if (v.empty()) {
+      tag_value_map_[tag] = std::string();
+    } else {
+      tag_value_map_[tag] = std::string(reinterpret_cast<const char*>(&v[0]),
+                                        v.size() * sizeof(T));
+    }
+  }
+
+  // Returns the message tag.
+  QuicTag tag() const { return tag_; }
+  // Sets the message tag.
+  void set_tag(QuicTag tag) { tag_ = tag; }
+
+  const QuicTagValueMap& tag_value_map() const { return tag_value_map_; }
+
+  // SetTaglist sets an element with the given tag to contain a list of tags,
+  // passed as varargs. The argument list must be terminated with a 0 element.
+  void SetTaglist(QuicTag tag, ...);
+
+  void SetStringPiece(QuicTag tag, base::StringPiece value);
+
+  // Erase removes a tag/value, if present, from the message.
+  void Erase(QuicTag tag);
+
+  // GetTaglist finds an element with the given tag containing zero or more
+  // tags. If such a tag doesn't exist, it returns false. Otherwise it sets
+  // |out_tags| and |out_len| to point to the array of tags and returns true.
+  // The array points into the CryptoHandshakeMessage and is valid only for as
+  // long as the CryptoHandshakeMessage exists and is not modified.
+  QuicErrorCode GetTaglist(QuicTag tag, const QuicTag** out_tags,
+                           size_t* out_len) const;
+
+  bool GetStringPiece(QuicTag tag, base::StringPiece* out) const;
+
+  // GetNthValue24 interprets the value with the given tag to be a series of
+  // 24-bit, length prefixed values and it returns the subvalue with the given
+  // index.
+  QuicErrorCode GetNthValue24(QuicTag tag,
+                              unsigned index,
+                              base::StringPiece* out) const;
+  QuicErrorCode GetUint16(QuicTag tag, uint16* out) const;
+  QuicErrorCode GetUint32(QuicTag tag, uint32* out) const;
+  QuicErrorCode GetUint64(QuicTag tag, uint64* out) const;
+
+  // size returns 4 (message tag) + 2 (uint16, number of entries) +
+  // (4 (tag) + 4 (end offset))*tag_value_map_.size() + ∑ value sizes.
+  size_t size() const;
+
+  // set_minimum_size sets the minimum number of bytes that the message should
+  // consume. The CryptoFramer will add a PAD tag as needed when serializing in
+  // order to ensure this. Setting a value of 0 disables padding.
+  //
+  // Padding is useful in order to ensure that messages are a minimum size. A
+  // QUIC server can require a minimum size in order to reduce the
+  // amplification factor of any mirror DoS attack.
+  void set_minimum_size(size_t min_bytes);
+
+  size_t minimum_size() const;
+
+  // DebugString returns a multi-line, string representation of the message
+  // suitable for including in debug output.
+  std::string DebugString() const;
+
+ private:
+  // GetPOD is a utility function for extracting a plain-old-data value. If
+  // |tag| exists in the message, and has a value of exactly |len| bytes then
+  // it copies |len| bytes of data into |out|. Otherwise |len| bytes at |out|
+  // are zeroed out.
+  //
+  // If used to copy integers then this assumes that the machine is
+  // little-endian.
+  QuicErrorCode GetPOD(QuicTag tag, void* out, size_t len) const;
+
+  std::string DebugStringInternal(size_t indent) const;
+
+  QuicTag tag_;
+  QuicTagValueMap tag_value_map_;
+
+  size_t minimum_size_;
+
+  // The serialized form of the handshake message. This member is constructed
+  // lasily.
+  mutable scoped_ptr<QuicData> serialized_;
+};
+
+}  // namespace net
+
+#endif  // NET_QUIC_CRYPTO_CRYPTO_HANDSHAKE_MESSAGE_H_