Move socket related files from net/base to net/socket.

Review URL: http://codereview.chromium.org/144009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18985 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 1190 insertions, 0 deletions

diff --git a/net/socket/ssl_client_socket_win.cc b/net/socket/ssl_client_socket_win.cc
new file mode 100644
index 0000000..bd2c594
--- /dev/null
+++ b/net/socket/ssl_client_socket_win.cc
@@ -0,0 +1,1190 @@
+// Copyright (c) 2006-2009 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/socket/ssl_client_socket_win.h"
+
+#include <schnlsp.h>
+
+#include "base/lock.h"
+#include "base/singleton.h"
+#include "base/stl_util-inl.h"
+#include "base/string_util.h"
+#include "net/base/connection_type_histograms.h"
+#include "net/base/io_buffer.h"
+#include "net/base/net_errors.h"
+#include "net/base/ssl_cert_request_info.h"
+#include "net/base/ssl_info.h"
+
+#pragma comment(lib, "secur32.lib")
+
+namespace net {
+
+//-----------------------------------------------------------------------------
+
+// TODO(wtc): See http://msdn.microsoft.com/en-us/library/aa377188(VS.85).aspx
+// for the other error codes we may need to map.
+static int MapSecurityError(SECURITY_STATUS err) {
+  // There are numerous security error codes, but these are the ones we thus
+  // far find interesting.
+  switch (err) {
+    case SEC_E_WRONG_PRINCIPAL:  // Schannel
+    case CERT_E_CN_NO_MATCH:  // CryptoAPI
+      return ERR_CERT_COMMON_NAME_INVALID;
+    case SEC_E_UNTRUSTED_ROOT:  // Schannel
+    case CERT_E_UNTRUSTEDROOT:  // CryptoAPI
+      return ERR_CERT_AUTHORITY_INVALID;
+    case SEC_E_CERT_EXPIRED:  // Schannel
+    case CERT_E_EXPIRED:  // CryptoAPI
+      return ERR_CERT_DATE_INVALID;
+    case CRYPT_E_NO_REVOCATION_CHECK:
+      return ERR_CERT_NO_REVOCATION_MECHANISM;
+    case CRYPT_E_REVOCATION_OFFLINE:
+      return ERR_CERT_UNABLE_TO_CHECK_REVOCATION;
+    case CRYPT_E_REVOKED:  // Schannel and CryptoAPI
+      return ERR_CERT_REVOKED;
+    case SEC_E_CERT_UNKNOWN:
+    case CERT_E_ROLE:
+      return ERR_CERT_INVALID;
+    // We received an unexpected_message or illegal_parameter alert message
+    // from the server.
+    case SEC_E_ILLEGAL_MESSAGE:
+      return ERR_SSL_PROTOCOL_ERROR;
+    case SEC_E_ALGORITHM_MISMATCH:
+      return ERR_SSL_VERSION_OR_CIPHER_MISMATCH;
+    case SEC_E_INVALID_HANDLE:
+      return ERR_UNEXPECTED;
+    case SEC_E_OK:
+      return OK;
+    default:
+      LOG(WARNING) << "Unknown error " << err << " mapped to net::ERR_FAILED";
+      return ERR_FAILED;
+  }
+}
+
+// Returns true if the two CERT_CONTEXTs contain the same certificate.
+bool SameCert(PCCERT_CONTEXT a, PCCERT_CONTEXT b) {
+  return a == b ||
+         (a->cbCertEncoded == b->cbCertEncoded &&
+         memcmp(a->pbCertEncoded, b->pbCertEncoded, b->cbCertEncoded) == 0);
+}
+
+//-----------------------------------------------------------------------------
+
+// A bitmask consisting of these bit flags encodes which versions of the SSL
+// protocol (SSL 2.0, SSL 3.0, and TLS 1.0) are enabled.
+enum {
+  SSL2 = 1 << 0,
+  SSL3 = 1 << 1,
+  TLS1 = 1 << 2,
+  SSL_VERSION_MASKS = 1 << 3  // The number of SSL version bitmasks.
+};
+
+// CredHandleClass simply gives a default constructor and a destructor to
+// SSPI's CredHandle type (a C struct).
+class CredHandleClass : public CredHandle {
+ public:
+  CredHandleClass() {
+    dwLower = 0;
+    dwUpper = 0;
+  }
+
+  ~CredHandleClass() {
+    if (dwLower || dwUpper) {
+      SECURITY_STATUS status = FreeCredentialsHandle(this);
+      DCHECK(status == SEC_E_OK);
+    }
+  }
+};
+
+// A table of CredHandles.
+class CredHandleTable {
+ public:
+  CredHandleTable() {}
+
+  ~CredHandleTable() {
+    STLDeleteContainerPairSecondPointers(client_cert_creds_.begin(),
+                                         client_cert_creds_.end());
+  }
+
+  CredHandle* GetHandle(PCCERT_CONTEXT client_cert, int ssl_version_mask) {
+    DCHECK(0 < ssl_version_mask &&
+           ssl_version_mask < arraysize(anonymous_creds_));
+    CredHandleClass* handle;
+    AutoLock lock(lock_);
+    if (client_cert) {
+      CredHandleMapKey key = std::make_pair(client_cert, ssl_version_mask);
+      CredHandleMap::const_iterator it = client_cert_creds_.find(key);
+      if (it == client_cert_creds_.end()) {
+        handle = new CredHandleClass;
+        client_cert_creds_[key] = handle;
+      } else {
+        handle = it->second;
+      }
+    } else {
+      handle = &anonymous_creds_[ssl_version_mask];
+    }
+    if (!handle->dwLower && !handle->dwUpper)
+      InitializeHandle(handle, client_cert, ssl_version_mask);
+    return handle;
+  }
+
+ private:
+  // CredHandleMapKey is a std::pair consisting of these two components:
+  //   PCCERT_CONTEXT client_cert
+  //   int ssl_version_mask
+  typedef std::pair<PCCERT_CONTEXT, int> CredHandleMapKey;
+
+  typedef std::map<CredHandleMapKey, CredHandleClass*> CredHandleMap;
+
+  static void InitializeHandle(CredHandle* handle,
+                               PCCERT_CONTEXT client_cert,
+                               int ssl_version_mask);
+
+  Lock lock_;
+
+  // Anonymous (no client certificate) CredHandles for all possible
+  // combinations of SSL versions.  Defined as an array for fast lookup.
+  CredHandleClass anonymous_creds_[SSL_VERSION_MASKS];
+
+  // CredHandles that use a client certificate.
+  CredHandleMap client_cert_creds_;
+};
+
+// static
+void CredHandleTable::InitializeHandle(CredHandle* handle,
+                                       PCCERT_CONTEXT client_cert,
+                                       int ssl_version_mask) {
+  SCHANNEL_CRED schannel_cred = {0};
+  schannel_cred.dwVersion = SCHANNEL_CRED_VERSION;
+  if (client_cert) {
+    schannel_cred.cCreds = 1;
+    schannel_cred.paCred = &client_cert;
+    // Schannel will make its own copy of client_cert.
+  }
+
+  // The global system registry settings take precedence over the value of
+  // schannel_cred.grbitEnabledProtocols.
+  schannel_cred.grbitEnabledProtocols = 0;
+  if (ssl_version_mask & SSL2)
+    schannel_cred.grbitEnabledProtocols |= SP_PROT_SSL2;
+  if (ssl_version_mask & SSL3)
+    schannel_cred.grbitEnabledProtocols |= SP_PROT_SSL3;
+  if (ssl_version_mask & TLS1)
+    schannel_cred.grbitEnabledProtocols |= SP_PROT_TLS1;
+
+  // The default session lifetime is 36000000 milliseconds (ten hours).  Set
+  // schannel_cred.dwSessionLifespan to change the number of milliseconds that
+  // Schannel keeps the session in its session cache.
+
+  // We can set the key exchange algorithms (RSA or DH) in
+  // schannel_cred.{cSupportedAlgs,palgSupportedAlgs}.
+
+  // Although SCH_CRED_AUTO_CRED_VALIDATION is convenient, we have to use
+  // SCH_CRED_MANUAL_CRED_VALIDATION for three reasons.
+  // 1. SCH_CRED_AUTO_CRED_VALIDATION doesn't allow us to get the certificate
+  //    context if the certificate validation fails.
+  // 2. SCH_CRED_AUTO_CRED_VALIDATION returns only one error even if the
+  //    certificate has multiple errors.
+  // 3. SCH_CRED_AUTO_CRED_VALIDATION doesn't allow us to ignore untrusted CA
+  //    and expired certificate errors.  There are only flags to ignore the
+  //    name mismatch and unable-to-check-revocation errors.
+  //
+  // TODO(wtc): Look into undocumented or poorly documented flags:
+  //   SCH_CRED_RESTRICTED_ROOTS
+  //   SCH_CRED_REVOCATION_CHECK_CACHE_ONLY
+  //   SCH_CRED_CACHE_ONLY_URL_RETRIEVAL
+  //   SCH_CRED_MEMORY_STORE_CERT
+  schannel_cred.dwFlags |= SCH_CRED_NO_DEFAULT_CREDS |
+                           SCH_CRED_MANUAL_CRED_VALIDATION;
+  TimeStamp expiry;
+  SECURITY_STATUS status;
+
+  status = AcquireCredentialsHandle(
+      NULL,  // Not used
+      UNISP_NAME,  // Microsoft Unified Security Protocol Provider
+      SECPKG_CRED_OUTBOUND,
+      NULL,  // Not used
+      &schannel_cred,
+      NULL,  // Not used
+      NULL,  // Not used
+      handle,
+      &expiry);  // Optional
+  if (status != SEC_E_OK) {
+    DLOG(ERROR) << "AcquireCredentialsHandle failed: " << status;
+    // GetHandle will return a pointer to an uninitialized CredHandle, which
+    // will cause InitializeSecurityContext to fail with SEC_E_INVALID_HANDLE.
+  }
+}
+
+// For the SSL sockets to share SSL sessions by session resumption handshakes,
+// they need to use the same CredHandle.  The GetCredHandle function creates
+// and returns a shared CredHandle.
+//
+// The versions of the SSL protocol enabled are a property of the CredHandle.
+// So we need a separate CredHandle for each combination of SSL versions.
+// Most of the time Chromium will use only one or two combinations of SSL
+// versions (for example, SSL3 | TLS1 for normal use, plus SSL3 when visiting
+// TLS-intolerant servers).  These CredHandles are initialized only when
+// needed.
+
+static CredHandle* GetCredHandle(PCCERT_CONTEXT client_cert,
+                                 int ssl_version_mask) {
+  // It doesn't matter whether GetCredHandle returns NULL or a pointer to an
+  // uninitialized CredHandle on failure.  Both of them cause
+  // InitializeSecurityContext to fail with SEC_E_INVALID_HANDLE.
+  if (ssl_version_mask <= 0 || ssl_version_mask >= SSL_VERSION_MASKS) {
+    NOTREACHED();
+    return NULL;
+  }
+  return Singleton<CredHandleTable>::get()->GetHandle(client_cert,
+                                                      ssl_version_mask);
+}
+
+//-----------------------------------------------------------------------------
+
+// A memory certificate store for client certificates.  This allows us to
+// close the "MY" system certificate store when we finish searching for
+// client certificates.
+class ClientCertStore {
+ public:
+  ClientCertStore() {
+    store_ = CertOpenStore(CERT_STORE_PROV_MEMORY, 0, NULL, 0, NULL);
+  }
+
+  ~ClientCertStore() {
+    if (store_) {
+      BOOL ok = CertCloseStore(store_, CERT_CLOSE_STORE_CHECK_FLAG);
+      DCHECK(ok);
+    }
+  }
+
+  PCCERT_CONTEXT CopyCertContext(PCCERT_CONTEXT client_cert) {
+    PCCERT_CONTEXT copy;
+    BOOL ok = CertAddCertificateContextToStore(store_, client_cert,
+                                               CERT_STORE_ADD_USE_EXISTING,
+                                               &copy);
+    DCHECK(ok);
+    return ok ? copy : NULL;
+  }
+
+ private:
+  HCERTSTORE store_;
+};
+
+//-----------------------------------------------------------------------------
+
+// Size of recv_buffer_
+//
+// Ciphertext is decrypted one SSL record at a time, so recv_buffer_ needs to
+// have room for a full SSL record, with the header and trailer.  Here is the
+// breakdown of the size:
+//   5: SSL record header
+//   16K: SSL record maximum size
+//   64: >= SSL record trailer (16 or 20 have been observed)
+static const int kRecvBufferSize = (5 + 16*1024 + 64);
+
+SSLClientSocketWin::SSLClientSocketWin(ClientSocket* transport_socket,
+                                       const std::string& hostname,
+                                       const SSLConfig& ssl_config)
+#pragma warning(suppress: 4355)
+    : io_callback_(this, &SSLClientSocketWin::OnIOComplete),
+      transport_(transport_socket),
+      hostname_(hostname),
+      ssl_config_(ssl_config),
+      user_callback_(NULL),
+      user_buf_len_(0),
+      next_state_(STATE_NONE),
+      creds_(NULL),
+      isc_status_(SEC_E_OK),
+      payload_send_buffer_len_(0),
+      bytes_sent_(0),
+      decrypted_ptr_(NULL),
+      bytes_decrypted_(0),
+      received_ptr_(NULL),
+      bytes_received_(0),
+      writing_first_token_(false),
+      completed_handshake_(false),
+      ignore_ok_result_(false),
+      renegotiating_(false) {
+  memset(&stream_sizes_, 0, sizeof(stream_sizes_));
+  memset(in_buffers_, 0, sizeof(in_buffers_));
+  memset(&send_buffer_, 0, sizeof(send_buffer_));
+  memset(&ctxt_, 0, sizeof(ctxt_));
+}
+
+SSLClientSocketWin::~SSLClientSocketWin() {
+  Disconnect();
+}
+
+void SSLClientSocketWin::GetSSLInfo(SSLInfo* ssl_info) {
+  if (!server_cert_)
+    return;
+
+  ssl_info->cert = server_cert_;
+  ssl_info->cert_status = server_cert_verify_result_.cert_status;
+  SecPkgContext_ConnectionInfo connection_info;
+  SECURITY_STATUS status = QueryContextAttributes(
+      &ctxt_, SECPKG_ATTR_CONNECTION_INFO, &connection_info);
+  if (status == SEC_E_OK) {
+    // TODO(wtc): compute the overall security strength, taking into account
+    // dwExchStrength and dwHashStrength.  dwExchStrength needs to be
+    // normalized.
+    ssl_info->security_bits = connection_info.dwCipherStrength;
+  }
+}
+
+void SSLClientSocketWin::GetSSLCertRequestInfo(
+    SSLCertRequestInfo* cert_request_info) {
+  cert_request_info->host_and_port = hostname_;  // TODO(wtc): no port!
+  cert_request_info->client_certs.clear();
+
+  // Get the certificate_authorities field of the CertificateRequest message.
+  // Schannel doesn't return the certificate_types field of the
+  // CertificateRequest message to us, so we can't filter the client
+  // certificates properly. :-(
+  SecPkgContext_IssuerListInfoEx issuer_list;
+  SECURITY_STATUS status = QueryContextAttributes(
+      &ctxt_, SECPKG_ATTR_ISSUER_LIST_EX, &issuer_list);
+  if (status != SEC_E_OK) {
+    DLOG(ERROR) << "QueryContextAttributes (issuer list) failed: " << status;
+    return;
+  }
+
+  // Client certificates of the user are in the "MY" system certificate store.
+  HCERTSTORE my_cert_store = CertOpenSystemStore(NULL, L"MY");
+  if (!my_cert_store) {
+    FreeContextBuffer(issuer_list.aIssuers);
+    return;
+  }
+
+  // Enumerate the client certificates.
+  CERT_CHAIN_FIND_BY_ISSUER_PARA find_by_issuer_para;
+  memset(&find_by_issuer_para, 0, sizeof(find_by_issuer_para));
+  find_by_issuer_para.cbSize = sizeof(find_by_issuer_para);
+  find_by_issuer_para.pszUsageIdentifier = szOID_PKIX_KP_CLIENT_AUTH;
+  find_by_issuer_para.cIssuer = issuer_list.cIssuers;
+  find_by_issuer_para.rgIssuer = issuer_list.aIssuers;
+
+  PCCERT_CHAIN_CONTEXT chain_context = NULL;
+
+  for (;;) {
+    // Find a certificate chain.
+    chain_context = CertFindChainInStore(my_cert_store,
+                                         X509_ASN_ENCODING,
+                                         0,
+                                         CERT_CHAIN_FIND_BY_ISSUER,
+                                         &find_by_issuer_para,
+                                         chain_context);
+    if (!chain_context) {
+      DWORD err = GetLastError();
+      if (err != CRYPT_E_NOT_FOUND)
+        DLOG(ERROR) << "CertFindChainInStore failed: " << err;
+      break;
+    }
+
+    // Get the leaf certificate.
+    PCCERT_CONTEXT cert_context =
+        chain_context->rgpChain[0]->rgpElement[0]->pCertContext;
+    // Copy it to our own certificate store, so that we can close the "MY"
+    // certificate store before returning from this function.
+    PCCERT_CONTEXT cert_context2 =
+        Singleton<ClientCertStore>::get()->CopyCertContext(cert_context);
+    if (!cert_context2) {
+      NOTREACHED();
+      continue;
+    }
+    scoped_refptr<X509Certificate> cert = X509Certificate::CreateFromHandle(
+        cert_context2, X509Certificate::SOURCE_LONE_CERT_IMPORT);
+    cert_request_info->client_certs.push_back(cert);
+  }
+
+  FreeContextBuffer(issuer_list.aIssuers);
+
+  BOOL ok = CertCloseStore(my_cert_store, CERT_CLOSE_STORE_CHECK_FLAG);
+  DCHECK(ok);
+}
+
+int SSLClientSocketWin::Connect(CompletionCallback* callback) {
+  DCHECK(transport_.get());
+  DCHECK(next_state_ == STATE_NONE);
+  DCHECK(!user_callback_);
+
+  int ssl_version_mask = 0;
+  if (ssl_config_.ssl2_enabled)
+    ssl_version_mask |= SSL2;
+  if (ssl_config_.ssl3_enabled)
+    ssl_version_mask |= SSL3;
+  if (ssl_config_.tls1_enabled)
+    ssl_version_mask |= TLS1;
+  // If we pass 0 to GetCredHandle, we will let Schannel select the protocols,
+  // rather than enabling no protocols.  So we have to fail here.
+  if (ssl_version_mask == 0)
+    return ERR_NO_SSL_VERSIONS_ENABLED;
+  PCCERT_CONTEXT cert_context = NULL;
+  if (ssl_config_.client_cert)
+    cert_context = ssl_config_.client_cert->os_cert_handle();
+  creds_ = GetCredHandle(cert_context, ssl_version_mask);
+
+  memset(&ctxt_, 0, sizeof(ctxt_));
+
+  SecBufferDesc buffer_desc;
+  DWORD out_flags;
+  DWORD flags = ISC_REQ_SEQUENCE_DETECT   |
+                ISC_REQ_REPLAY_DETECT     |
+                ISC_REQ_CONFIDENTIALITY   |
+                ISC_RET_EXTENDED_ERROR    |
+                ISC_REQ_ALLOCATE_MEMORY   |
+                ISC_REQ_STREAM;
+
+  send_buffer_.pvBuffer = NULL;
+  send_buffer_.BufferType = SECBUFFER_TOKEN;
+  send_buffer_.cbBuffer = 0;
+
+  buffer_desc.cBuffers = 1;
+  buffer_desc.pBuffers = &send_buffer_;
+  buffer_desc.ulVersion = SECBUFFER_VERSION;
+
+  TimeStamp expiry;
+  SECURITY_STATUS status;
+
+  status = InitializeSecurityContext(
+      creds_,
+      NULL,  // NULL on the first call
+      const_cast<wchar_t*>(ASCIIToWide(hostname_).c_str()),
+      flags,
+      0,  // Reserved
+      SECURITY_NATIVE_DREP,  // TODO(wtc): MSDN says this should be set to 0.
+      NULL,  // NULL on the first call
+      0,  // Reserved
+      &ctxt_,  // Receives the new context handle
+      &buffer_desc,
+      &out_flags,
+      &expiry);
+  if (status != SEC_I_CONTINUE_NEEDED) {
+    DLOG(ERROR) << "InitializeSecurityContext failed: " << status;
+    return MapSecurityError(status);
+  }
+
+  writing_first_token_ = true;
+  next_state_ = STATE_HANDSHAKE_WRITE;
+  int rv = DoLoop(OK);
+  if (rv == ERR_IO_PENDING)
+    user_callback_ = callback;
+  return rv;
+}
+
+void SSLClientSocketWin::Disconnect() {
+  // TODO(wtc): Send SSL close_notify alert.
+  completed_handshake_ = false;
+  transport_->Disconnect();
+
+  if (send_buffer_.pvBuffer)
+    FreeSendBuffer();
+  if (ctxt_.dwLower || ctxt_.dwUpper) {
+    DeleteSecurityContext(&ctxt_);
+    memset(&ctxt_, 0, sizeof(ctxt_));
+  }
+  if (server_cert_)
+    server_cert_ = NULL;
+
+  // TODO(wtc): reset more members?
+  bytes_decrypted_ = 0;
+  bytes_received_ = 0;
+  writing_first_token_ = false;
+  renegotiating_ = false;
+}
+
+bool SSLClientSocketWin::IsConnected() const {
+  // Ideally, we should also check if we have received the close_notify alert
+  // message from the server, and return false in that case.  We're not doing
+  // that, so this function may return a false positive.  Since the upper
+  // layer (HttpNetworkTransaction) needs to handle a persistent connection
+  // closed by the server when we send a request anyway, a false positive in
+  // exchange for simpler code is a good trade-off.
+  return completed_handshake_ && transport_->IsConnected();
+}
+
+bool SSLClientSocketWin::IsConnectedAndIdle() const {
+  // Unlike IsConnected, this method doesn't return a false positive.
+  //
+  // Strictly speaking, we should check if we have received the close_notify
+  // alert message from the server, and return false in that case.  Although
+  // the close_notify alert message means EOF in the SSL layer, it is just
+  // bytes to the transport layer below, so transport_->IsConnectedAndIdle()
+  // returns the desired false when we receive close_notify.
+  return completed_handshake_ && transport_->IsConnectedAndIdle();
+}
+
+int SSLClientSocketWin::Read(IOBuffer* buf, int buf_len,
+                             CompletionCallback* callback) {
+  DCHECK(completed_handshake_);
+  DCHECK(next_state_ == STATE_NONE);
+  DCHECK(!user_callback_);
+
+  // If we have surplus decrypted plaintext, satisfy the Read with it without
+  // reading more ciphertext from the transport socket.
+  if (bytes_decrypted_ != 0) {
+    int len = std::min(buf_len, bytes_decrypted_);
+    memcpy(buf->data(), decrypted_ptr_, len);
+    decrypted_ptr_ += len;
+    bytes_decrypted_ -= len;
+    if (bytes_decrypted_ == 0) {
+      decrypted_ptr_ = NULL;
+      if (bytes_received_ != 0) {
+        memmove(recv_buffer_.get(), received_ptr_, bytes_received_);
+        received_ptr_ = recv_buffer_.get();
+      }
+    }
+    return len;
+  }
+
+  DCHECK(!user_buf_);
+  user_buf_ = buf;
+  user_buf_len_ = buf_len;
+
+  SetNextStateForRead();
+  int rv = DoLoop(OK);
+  if (rv == ERR_IO_PENDING) {
+    user_callback_ = callback;
+  } else {
+    user_buf_ = NULL;
+  }
+  return rv;
+}
+
+int SSLClientSocketWin::Write(IOBuffer* buf, int buf_len,
+                              CompletionCallback* callback) {
+  DCHECK(completed_handshake_);
+  DCHECK(next_state_ == STATE_NONE);
+  DCHECK(!user_callback_);
+
+  DCHECK(!user_buf_);
+  user_buf_ = buf;
+  user_buf_len_ = buf_len;
+
+  next_state_ = STATE_PAYLOAD_ENCRYPT;
+  int rv = DoLoop(OK);
+  if (rv == ERR_IO_PENDING) {
+    user_callback_ = callback;
+  } else {
+    user_buf_ = NULL;
+  }
+  return rv;
+}
+
+void SSLClientSocketWin::DoCallback(int rv) {
+  DCHECK(rv != ERR_IO_PENDING);
+  DCHECK(user_callback_);
+
+  // since Run may result in Read being called, clear user_callback_ up front.
+  CompletionCallback* c = user_callback_;
+  user_callback_ = NULL;
+  user_buf_ = NULL;
+  c->Run(rv);
+}
+
+void SSLClientSocketWin::OnIOComplete(int result) {
+  int rv = DoLoop(result);
+  if (rv != ERR_IO_PENDING)
+    DoCallback(rv);
+}
+
+int SSLClientSocketWin::DoLoop(int last_io_result) {
+  DCHECK(next_state_ != STATE_NONE);
+  int rv = last_io_result;
+  do {
+    State state = next_state_;
+    next_state_ = STATE_NONE;
+    switch (state) {
+      case STATE_HANDSHAKE_READ:
+        rv = DoHandshakeRead();
+        break;
+      case STATE_HANDSHAKE_READ_COMPLETE:
+        rv = DoHandshakeReadComplete(rv);
+        break;
+      case STATE_HANDSHAKE_WRITE:
+        rv = DoHandshakeWrite();
+        break;
+      case STATE_HANDSHAKE_WRITE_COMPLETE:
+        rv = DoHandshakeWriteComplete(rv);
+        break;
+      case STATE_VERIFY_CERT:
+        rv = DoVerifyCert();
+        break;
+      case STATE_VERIFY_CERT_COMPLETE:
+        rv = DoVerifyCertComplete(rv);
+        break;
+      case STATE_PAYLOAD_READ:
+        rv = DoPayloadRead();
+        break;
+      case STATE_PAYLOAD_READ_COMPLETE:
+        rv = DoPayloadReadComplete(rv);
+        break;
+      case STATE_PAYLOAD_ENCRYPT:
+        rv = DoPayloadEncrypt();
+        break;
+      case STATE_PAYLOAD_WRITE:
+        rv = DoPayloadWrite();
+        break;
+      case STATE_PAYLOAD_WRITE_COMPLETE:
+        rv = DoPayloadWriteComplete(rv);
+        break;
+      default:
+        rv = ERR_UNEXPECTED;
+        NOTREACHED() << "unexpected state";
+        break;
+    }
+  } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
+  return rv;
+}
+
+int SSLClientSocketWin::DoHandshakeRead() {
+  next_state_ = STATE_HANDSHAKE_READ_COMPLETE;
+
+  if (!recv_buffer_.get())
+    recv_buffer_.reset(new char[kRecvBufferSize]);
+
+  int buf_len = kRecvBufferSize - bytes_received_;
+
+  if (buf_len <= 0) {
+    NOTREACHED() << "Receive buffer is too small!";
+    return ERR_UNEXPECTED;
+  }
+
+  DCHECK(!transport_buf_);
+  transport_buf_ = new IOBuffer(buf_len);
+
+  return transport_->Read(transport_buf_, buf_len, &io_callback_);
+}
+
+int SSLClientSocketWin::DoHandshakeReadComplete(int result) {
+  if (result < 0) {
+    transport_buf_ = NULL;
+    return result;
+  }
+
+  if (transport_buf_) {
+    // A transition to STATE_HANDSHAKE_READ_COMPLETE is set in multiple places,
+    // not only in DoHandshakeRead(), so we may not have a transport_buf_.
+    DCHECK_LE(result, kRecvBufferSize - bytes_received_);
+    char* buf = recv_buffer_.get() + bytes_received_;
+    memcpy(buf, transport_buf_->data(), result);
+    transport_buf_ = NULL;
+  }
+
+  if (result == 0 && !ignore_ok_result_)
+    return ERR_SSL_PROTOCOL_ERROR;  // Incomplete response :(
+
+  ignore_ok_result_ = false;
+
+  bytes_received_ += result;
+
+  // Process the contents of recv_buffer_.
+  TimeStamp expiry;
+  DWORD out_flags;
+
+  DWORD flags = ISC_REQ_SEQUENCE_DETECT |
+                ISC_REQ_REPLAY_DETECT |
+                ISC_REQ_CONFIDENTIALITY |
+                ISC_RET_EXTENDED_ERROR |
+                ISC_REQ_ALLOCATE_MEMORY |
+                ISC_REQ_STREAM;
+
+  if (ssl_config_.send_client_cert)
+    flags |= ISC_REQ_USE_SUPPLIED_CREDS;
+
+  SecBufferDesc in_buffer_desc, out_buffer_desc;
+
+  in_buffer_desc.cBuffers = 2;
+  in_buffer_desc.pBuffers = in_buffers_;
+  in_buffer_desc.ulVersion = SECBUFFER_VERSION;
+
+  in_buffers_[0].pvBuffer = recv_buffer_.get();
+  in_buffers_[0].cbBuffer = bytes_received_;
+  in_buffers_[0].BufferType = SECBUFFER_TOKEN;
+
+  in_buffers_[1].pvBuffer = NULL;
+  in_buffers_[1].cbBuffer = 0;
+  in_buffers_[1].BufferType = SECBUFFER_EMPTY;
+
+  out_buffer_desc.cBuffers = 1;
+  out_buffer_desc.pBuffers = &send_buffer_;
+  out_buffer_desc.ulVersion = SECBUFFER_VERSION;
+
+  send_buffer_.pvBuffer = NULL;
+  send_buffer_.BufferType = SECBUFFER_TOKEN;
+  send_buffer_.cbBuffer = 0;
+
+  isc_status_ = InitializeSecurityContext(
+      creds_,
+      &ctxt_,
+      NULL,
+      flags,
+      0,
+      SECURITY_NATIVE_DREP,
+      &in_buffer_desc,
+      0,
+      NULL,
+      &out_buffer_desc,
+      &out_flags,
+      &expiry);
+
+  if (send_buffer_.cbBuffer != 0 &&
+      (isc_status_ == SEC_E_OK ||
+       isc_status_ == SEC_I_CONTINUE_NEEDED ||
+      (FAILED(isc_status_) && (out_flags & ISC_RET_EXTENDED_ERROR)))) {
+    next_state_ = STATE_HANDSHAKE_WRITE;
+    return OK;
+  }
+  return DidCallInitializeSecurityContext();
+}
+
+int SSLClientSocketWin::DidCallInitializeSecurityContext() {
+  if (isc_status_ == SEC_E_INCOMPLETE_MESSAGE) {
+    next_state_ = STATE_HANDSHAKE_READ;
+    return OK;
+  }
+
+  if (isc_status_ == SEC_E_OK) {
+    if (in_buffers_[1].BufferType == SECBUFFER_EXTRA) {
+      // Save this data for later.
+      memmove(recv_buffer_.get(),
+              recv_buffer_.get() + (bytes_received_ - in_buffers_[1].cbBuffer),
+              in_buffers_[1].cbBuffer);
+      bytes_received_ = in_buffers_[1].cbBuffer;
+    } else {
+      bytes_received_ = 0;
+    }
+    return DidCompleteHandshake();
+  }
+
+  if (FAILED(isc_status_)) {
+    int result = MapSecurityError(isc_status_);
+    // We told Schannel to not verify the server certificate
+    // (SCH_CRED_MANUAL_CRED_VALIDATION), so any certificate error returned by
+    // InitializeSecurityContext must be referring to the bad or missing
+    // client certificate.
+    if (IsCertificateError(result)) {
+      // TODO(wtc): Add new error codes for client certificate errors reported
+      // by the server using SSL/TLS alert messages.  See the MSDN page
+      // "Schannel Error Codes for TLS and SSL Alerts", which maps TLS alert
+      // messages to Windows error codes:
+      // http://msdn.microsoft.com/en-us/library/dd721886%28VS.85%29.aspx
+      return ERR_BAD_SSL_CLIENT_AUTH_CERT;
+    }
+    return result;
+  }
+
+  if (isc_status_ == SEC_I_INCOMPLETE_CREDENTIALS)
+    return ERR_SSL_CLIENT_AUTH_CERT_NEEDED;
+
+  DCHECK(isc_status_ == SEC_I_CONTINUE_NEEDED);
+  if (in_buffers_[1].BufferType == SECBUFFER_EXTRA) {
+    memmove(recv_buffer_.get(),
+            recv_buffer_.get() + (bytes_received_ - in_buffers_[1].cbBuffer),
+            in_buffers_[1].cbBuffer);
+    bytes_received_ = in_buffers_[1].cbBuffer;
+    next_state_ = STATE_HANDSHAKE_READ_COMPLETE;
+    ignore_ok_result_ = true;  // OK doesn't mean EOF.
+    return OK;
+  }
+
+  bytes_received_ = 0;
+  next_state_ = STATE_HANDSHAKE_READ;
+  return OK;
+}
+
+int SSLClientSocketWin::DoHandshakeWrite() {
+  next_state_ = STATE_HANDSHAKE_WRITE_COMPLETE;
+
+  // We should have something to send.
+  DCHECK(send_buffer_.pvBuffer);
+  DCHECK(send_buffer_.cbBuffer > 0);
+  DCHECK(!transport_buf_);
+
+  const char* buf = static_cast<char*>(send_buffer_.pvBuffer) + bytes_sent_;
+  int buf_len = send_buffer_.cbBuffer - bytes_sent_;
+  transport_buf_ = new IOBuffer(buf_len);
+  memcpy(transport_buf_->data(), buf, buf_len);
+
+  return transport_->Write(transport_buf_, buf_len, &io_callback_);
+}
+
+int SSLClientSocketWin::DoHandshakeWriteComplete(int result) {
+  DCHECK(transport_buf_);
+  transport_buf_ = NULL;
+  if (result < 0)
+    return result;
+
+  DCHECK(result != 0);
+
+  bytes_sent_ += result;
+  DCHECK(bytes_sent_ <= static_cast<int>(send_buffer_.cbBuffer));
+
+  if (bytes_sent_ >= static_cast<int>(send_buffer_.cbBuffer)) {
+    bool overflow = (bytes_sent_ > static_cast<int>(send_buffer_.cbBuffer));
+    FreeSendBuffer();
+    bytes_sent_ = 0;
+    if (overflow)  // Bug!
+      return ERR_UNEXPECTED;
+    if (writing_first_token_) {
+      writing_first_token_ = false;
+      DCHECK(bytes_received_ == 0);
+      next_state_ = STATE_HANDSHAKE_READ;
+      return OK;
+    }
+    return DidCallInitializeSecurityContext();
+  }
+
+  // Send the remaining bytes.
+  next_state_ = STATE_HANDSHAKE_WRITE;
+  return OK;
+}
+
+// Set server_cert_status_ and return OK or a network error.
+int SSLClientSocketWin::DoVerifyCert() {
+  next_state_ = STATE_VERIFY_CERT_COMPLETE;
+
+  DCHECK(server_cert_);
+
+  return verifier_.Verify(server_cert_, hostname_,
+                          ssl_config_.rev_checking_enabled,
+                          &server_cert_verify_result_, &io_callback_);
+}
+
+int SSLClientSocketWin::DoVerifyCertComplete(int result) {
+  // If we have been explicitly told to accept this certificate, override the
+  // result of verifier_.Verify.
+  // Eventually, we should cache the cert verification results so that we don't
+  // need to call verifier_.Verify repeatedly. But for now we need to do this.
+  // Alternatively, we might be able to store the cert's status along with
+  // the cert in the allowed_bad_certs_ set.
+  if (IsCertificateError(result) &&
+      ssl_config_.allowed_bad_certs_.count(server_cert_))
+    result = OK;
+
+  LogConnectionTypeMetrics();
+  if (renegotiating_) {
+    DidCompleteRenegotiation(result);
+  } else {
+    // The initial handshake, kicked off by a Connect, has completed.
+    completed_handshake_ = true;
+    // Exit DoLoop and return the result to the caller of Connect.
+    DCHECK(next_state_ == STATE_NONE);
+  }
+  return result;
+}
+
+int SSLClientSocketWin::DoPayloadRead() {
+  next_state_ = STATE_PAYLOAD_READ_COMPLETE;
+
+  DCHECK(recv_buffer_.get());
+
+  int buf_len = kRecvBufferSize - bytes_received_;
+
+  if (buf_len <= 0) {
+    NOTREACHED() << "Receive buffer is too small!";
+    return ERR_FAILED;
+  }
+
+  DCHECK(!transport_buf_);
+  transport_buf_ = new IOBuffer(buf_len);
+
+  return transport_->Read(transport_buf_, buf_len, &io_callback_);
+}
+
+int SSLClientSocketWin::DoPayloadReadComplete(int result) {
+  if (result < 0) {
+    transport_buf_ = NULL;
+    return result;
+  }
+  if (transport_buf_) {
+    // This method is called after a state transition following DoPayloadRead(),
+    // or if SetNextStateForRead() was called. We have a transport_buf_ only
+    // in the first case, and we have to transfer the data from transport_buf_
+    // to recv_buffer_.
+    DCHECK_LE(result, kRecvBufferSize - bytes_received_);
+    char* buf = recv_buffer_.get() + bytes_received_;
+    memcpy(buf, transport_buf_->data(), result);
+    transport_buf_ = NULL;
+  }
+
+  if (result == 0 && !ignore_ok_result_) {
+    // TODO(wtc): Unless we have received the close_notify alert, we need to
+    // return an error code indicating that the SSL connection ended
+    // uncleanly, a potential truncation attack.
+    if (bytes_received_ != 0)
+      return ERR_FAILED;
+    return OK;
+  }
+
+  ignore_ok_result_ = false;
+
+  bytes_received_ += result;
+
+  // Process the contents of recv_buffer_.
+  SecBuffer buffers[4];
+  buffers[0].pvBuffer = recv_buffer_.get();
+  buffers[0].cbBuffer = bytes_received_;
+  buffers[0].BufferType = SECBUFFER_DATA;
+
+  buffers[1].BufferType = SECBUFFER_EMPTY;
+  buffers[2].BufferType = SECBUFFER_EMPTY;
+  buffers[3].BufferType = SECBUFFER_EMPTY;
+
+  SecBufferDesc buffer_desc;
+  buffer_desc.cBuffers = 4;
+  buffer_desc.pBuffers = buffers;
+  buffer_desc.ulVersion = SECBUFFER_VERSION;
+
+  SECURITY_STATUS status;
+  status = DecryptMessage(&ctxt_, &buffer_desc, 0, NULL);
+
+  if (status == SEC_E_INCOMPLETE_MESSAGE) {
+    next_state_ = STATE_PAYLOAD_READ;
+    return OK;
+  }
+
+  if (status == SEC_I_CONTEXT_EXPIRED) {
+    // Received the close_notify alert.
+    bytes_received_ = 0;
+    return OK;
+  }
+
+  if (status != SEC_E_OK && status != SEC_I_RENEGOTIATE) {
+    DCHECK(status != SEC_E_MESSAGE_ALTERED);
+    return MapSecurityError(status);
+  }
+
+  // The received ciphertext was decrypted in place in recv_buffer_.  Remember
+  // the location and length of the decrypted plaintext and any unused
+  // ciphertext.
+  decrypted_ptr_ = NULL;
+  bytes_decrypted_ = 0;
+  received_ptr_ = NULL;
+  bytes_received_ = 0;
+  for (int i = 1; i < 4; i++) {
+    if (!decrypted_ptr_ && buffers[i].BufferType == SECBUFFER_DATA) {
+      decrypted_ptr_ = static_cast<char*>(buffers[i].pvBuffer);
+      bytes_decrypted_ = buffers[i].cbBuffer;
+    }
+    if (!received_ptr_ && buffers[i].BufferType == SECBUFFER_EXTRA) {
+      received_ptr_ = static_cast<char*>(buffers[i].pvBuffer);
+      bytes_received_ = buffers[i].cbBuffer;
+    }
+  }
+
+  int len = 0;
+  if (bytes_decrypted_ != 0) {
+    len = std::min(user_buf_len_, bytes_decrypted_);
+    memcpy(user_buf_->data(), decrypted_ptr_, len);
+    decrypted_ptr_ += len;
+    bytes_decrypted_ -= len;
+  }
+  if (bytes_decrypted_ == 0) {
+    decrypted_ptr_ = NULL;
+    if (bytes_received_ != 0) {
+      memmove(recv_buffer_.get(), received_ptr_, bytes_received_);
+      received_ptr_ = recv_buffer_.get();
+    }
+  }
+
+  if (status == SEC_I_RENEGOTIATE) {
+    if (bytes_received_ != 0) {
+      // The server requested renegotiation, but there are some data yet to
+      // be decrypted.  The Platform SDK WebClient.c sample doesn't handle
+      // this, so we don't know how to handle this.  Assume this cannot
+      // happen.
+      LOG(ERROR) << "DecryptMessage returned SEC_I_RENEGOTIATE with a buffer "
+                 << "of type SECBUFFER_EXTRA.";
+      return ERR_SSL_RENEGOTIATION_REQUESTED;
+    }
+    if (len != 0) {
+      // The server requested renegotiation, but there are some decrypted
+      // data.  We can't start renegotiation until we have returned all
+      // decrypted data to the caller.
+      //
+      // This hasn't happened during testing.  Assume this cannot happen even
+      // though we know how to handle this.
+      LOG(ERROR) << "DecryptMessage returned SEC_I_RENEGOTIATE with a buffer "
+                 << "of type SECBUFFER_DATA.";
+      return ERR_SSL_RENEGOTIATION_REQUESTED;
+    }
+    // Jump to the handshake sequence.  Will come back when the rehandshake is
+    // done.
+    renegotiating_ = true;
+    next_state_ = STATE_HANDSHAKE_READ_COMPLETE;
+    ignore_ok_result_ = true;  // OK doesn't mean EOF.
+    return len;
+  }
+
+  // If we decrypted 0 bytes, don't report 0 bytes read, which would be
+  // mistaken for EOF.  Continue decrypting or read more.
+  if (len == 0)
+    SetNextStateForRead();
+  return len;
+}
+
+int SSLClientSocketWin::DoPayloadEncrypt() {
+  DCHECK(user_buf_);
+  DCHECK(user_buf_len_ > 0);
+
+  ULONG message_len = std::min(
+      stream_sizes_.cbMaximumMessage, static_cast<ULONG>(user_buf_len_));
+  ULONG alloc_len =
+      message_len + stream_sizes_.cbHeader + stream_sizes_.cbTrailer;
+  user_buf_len_ = message_len;
+
+  payload_send_buffer_.reset(new char[alloc_len]);
+  memcpy(&payload_send_buffer_[stream_sizes_.cbHeader],
+         user_buf_->data(), message_len);
+
+  SecBuffer buffers[4];
+  buffers[0].pvBuffer = payload_send_buffer_.get();
+  buffers[0].cbBuffer = stream_sizes_.cbHeader;
+  buffers[0].BufferType = SECBUFFER_STREAM_HEADER;
+
+  buffers[1].pvBuffer = &payload_send_buffer_[stream_sizes_.cbHeader];
+  buffers[1].cbBuffer = message_len;
+  buffers[1].BufferType = SECBUFFER_DATA;
+
+  buffers[2].pvBuffer = &payload_send_buffer_[stream_sizes_.cbHeader +
+                                              message_len];
+  buffers[2].cbBuffer = stream_sizes_.cbTrailer;
+  buffers[2].BufferType = SECBUFFER_STREAM_TRAILER;
+
+  buffers[3].BufferType = SECBUFFER_EMPTY;
+
+  SecBufferDesc buffer_desc;
+  buffer_desc.cBuffers = 4;
+  buffer_desc.pBuffers = buffers;
+  buffer_desc.ulVersion = SECBUFFER_VERSION;
+
+  SECURITY_STATUS status = EncryptMessage(&ctxt_, 0, &buffer_desc, 0);
+
+  if (FAILED(status))
+    return MapSecurityError(status);
+
+  payload_send_buffer_len_ = buffers[0].cbBuffer +
+                             buffers[1].cbBuffer +
+                             buffers[2].cbBuffer;
+  DCHECK(bytes_sent_ == 0);
+
+  next_state_ = STATE_PAYLOAD_WRITE;
+  return OK;
+}
+
+int SSLClientSocketWin::DoPayloadWrite() {
+  next_state_ = STATE_PAYLOAD_WRITE_COMPLETE;
+
+  // We should have something to send.
+  DCHECK(payload_send_buffer_.get());
+  DCHECK(payload_send_buffer_len_ > 0);
+  DCHECK(!transport_buf_);
+
+  const char* buf = payload_send_buffer_.get() + bytes_sent_;
+  int buf_len = payload_send_buffer_len_ - bytes_sent_;
+  transport_buf_ = new IOBuffer(buf_len);
+  memcpy(transport_buf_->data(), buf, buf_len);
+
+  return transport_->Write(transport_buf_, buf_len, &io_callback_);
+}
+
+int SSLClientSocketWin::DoPayloadWriteComplete(int result) {
+  DCHECK(transport_buf_);
+  transport_buf_ = NULL;
+  if (result < 0)
+    return result;
+
+  DCHECK(result != 0);
+
+  bytes_sent_ += result;
+  DCHECK(bytes_sent_ <= payload_send_buffer_len_);
+
+  if (bytes_sent_ >= payload_send_buffer_len_) {
+    bool overflow = (bytes_sent_ > payload_send_buffer_len_);
+    payload_send_buffer_.reset();
+    payload_send_buffer_len_ = 0;
+    bytes_sent_ = 0;
+    if (overflow)  // Bug!
+      return ERR_UNEXPECTED;
+    // Done
+    return user_buf_len_;
+  }
+
+  // Send the remaining bytes.
+  next_state_ = STATE_PAYLOAD_WRITE;
+  return OK;
+}
+
+int SSLClientSocketWin::DidCompleteHandshake() {
+  SECURITY_STATUS status = QueryContextAttributes(
+      &ctxt_, SECPKG_ATTR_STREAM_SIZES, &stream_sizes_);
+  if (status != SEC_E_OK) {
+    DLOG(ERROR) << "QueryContextAttributes (stream sizes) failed: " << status;
+    return MapSecurityError(status);
+  }
+  DCHECK(!server_cert_ || renegotiating_);
+  PCCERT_CONTEXT server_cert_handle = NULL;
+  status = QueryContextAttributes(
+      &ctxt_, SECPKG_ATTR_REMOTE_CERT_CONTEXT, &server_cert_handle);
+  if (status != SEC_E_OK) {
+    DLOG(ERROR) << "QueryContextAttributes (remote cert) failed: " << status;
+    return MapSecurityError(status);
+  }
+  if (renegotiating_ &&
+      SameCert(server_cert_->os_cert_handle(), server_cert_handle)) {
+    // We already verified the server certificate.  Either it is good or the
+    // user has accepted the certificate error.
+    CertFreeCertificateContext(server_cert_handle);
+    DidCompleteRenegotiation(OK);
+  } else {
+    server_cert_ = X509Certificate::CreateFromHandle(
+        server_cert_handle, X509Certificate::SOURCE_FROM_NETWORK);
+
+    next_state_ = STATE_VERIFY_CERT;
+  }
+  return OK;
+}
+
+// Called when a renegotiation is completed.  |result| is the verification
+// result of the server certificate received during renegotiation.
+void SSLClientSocketWin::DidCompleteRenegotiation(int result) {
+  // A rehandshake, started in the middle of a Read, has completed.
+  renegotiating_ = false;
+  // Pick up where we left off.  Go back to reading data.
+  if (result == OK)
+    SetNextStateForRead();
+}
+
+void SSLClientSocketWin::LogConnectionTypeMetrics() const {
+  UpdateConnectionTypeHistograms(CONNECTION_SSL);
+  if (server_cert_verify_result_.has_md5)
+    UpdateConnectionTypeHistograms(CONNECTION_SSL_MD5);
+  if (server_cert_verify_result_.has_md2)
+    UpdateConnectionTypeHistograms(CONNECTION_SSL_MD2);
+  if (server_cert_verify_result_.has_md4)
+    UpdateConnectionTypeHistograms(CONNECTION_SSL_MD4);
+  if (server_cert_verify_result_.has_md5_ca)
+    UpdateConnectionTypeHistograms(CONNECTION_SSL_MD5_CA);
+  if (server_cert_verify_result_.has_md2_ca)
+    UpdateConnectionTypeHistograms(CONNECTION_SSL_MD2_CA);
+}
+
+void SSLClientSocketWin::SetNextStateForRead() {
+  if (bytes_received_ == 0) {
+    next_state_ = STATE_PAYLOAD_READ;
+  } else {
+    next_state_ = STATE_PAYLOAD_READ_COMPLETE;
+    ignore_ok_result_ = true;  // OK doesn't mean EOF.
+  }
+}
+
+void SSLClientSocketWin::FreeSendBuffer() {
+  SECURITY_STATUS status = FreeContextBuffer(send_buffer_.pvBuffer);
+  DCHECK(status == SEC_E_OK);
+  memset(&send_buffer_, 0, sizeof(send_buffer_));
+}
+
+}  // namespace net