Sign CertificateVerify messages on a background thread.

net/ssl/ssl_platform_key_mac.cc

+// Copyright 2014 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/ssl/ssl_platform_key.h"
+
+#include <openssl/ecdsa.h>
+#include <openssl/obj.h>
+#include <openssl/rsa.h>
+
+#include <Security/cssm.h>
+#include <Security/SecBase.h>
+#include <Security/SecCertificate.h>
+#include <Security/SecIdentity.h>
+#include <Security/SecKey.h>
+
+#include "base/lazy_instance.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/mac/mac_logging.h"
+#include "base/mac/scoped_cftyperef.h"
+#include "base/memory/scoped_policy.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/sequenced_task_runner.h"
+#include "base/stl_util.h"
+#include "base/synchronization/lock.h"
+#include "crypto/mac_security_services_lock.h"
+#include "crypto/openssl_util.h"
+#include "crypto/scoped_openssl_types.h"
+#include "net/base/net_errors.h"
+#include "net/cert/x509_certificate.h"
+#include "net/ssl/ssl_private_key.h"
+#include "net/ssl/threaded_ssl_private_key.h"
+
+namespace net {
+
+namespace {
+
+class ScopedCSSM_CC_HANDLE {
+ public:
+  ScopedCSSM_CC_HANDLE() : handle_(0) {}
+
+  ~ScopedCSSM_CC_HANDLE() { reset(); }
+
+  CSSM_CC_HANDLE get() const { return handle_; }
+
+  void reset() {
+    if (handle_)
+      CSSM_DeleteContext(handle_);
+    handle_ = 0;
+  }
+
+ private:
+  CSSM_CC_HANDLE handle_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedCSSM_CC_HANDLE);
+};
+
+// Looks up the private key for |certificate| in KeyChain and returns
+// a SecKeyRef or nullptr on failure. The caller takes ownership of the
+// result.
+SecKeyRef FetchSecKeyRefForCertificate(const X509Certificate* certificate) {
+  OSStatus status;
+  base::ScopedCFTypeRef<SecIdentityRef> identity;
+  {
+    base::AutoLock lock(crypto::GetMacSecurityServicesLock());
+    status = SecIdentityCreateWithCertificate(
+        nullptr, certificate->os_cert_handle(), identity.InitializeInto());
+  }
+  if (status != noErr) {
+    OSSTATUS_LOG(WARNING, status);
+    return nullptr;
+  }
+
+  base::ScopedCFTypeRef<SecKeyRef> private_key;
+  status = SecIdentityCopyPrivateKey(identity, private_key.InitializeInto());
+  if (status != noErr) {
+    OSSTATUS_LOG(WARNING, status);
+    return nullptr;
+  }
+
+  return private_key.release();
+}
+
+class SSLPlatformKeyMac : public ThreadedSSLPrivateKey::Delegate {
+ public:
+  SSLPlatformKeyMac(SecKeyRef key, const CSSM_KEY* cssm_key)
+      : key_(key, base::scoped_policy::RETAIN), cssm_key_(cssm_key) {
+    DCHECK(cssm_key_->KeyHeader.AlgorithmId == CSSM_ALGID_RSA ||
+           cssm_key_->KeyHeader.AlgorithmId == CSSM_ALGID_ECDSA);
+  }
+
+  ~SSLPlatformKeyMac() override {}
+
+  SSLPrivateKey::Type GetType() override {
+    if (cssm_key_->KeyHeader.AlgorithmId == CSSM_ALGID_RSA) {
+      return SSLPrivateKey::Type::RSA;
+    } else {
+      DCHECK_EQ(CSSM_ALGID_ECDSA, cssm_key_->KeyHeader.AlgorithmId);
+      return SSLPrivateKey::Type::ECDSA;
+    }
+  }
+
+  bool SupportsHash(SSLPrivateKey::Hash hash) override { return true; }
+
+  size_t GetMaxSignatureLengthInBytes() override {
+    if (cssm_key_->KeyHeader.AlgorithmId == CSSM_ALGID_RSA) {
+      return (cssm_key_->KeyHeader.LogicalKeySizeInBits + 7) / 8;
+    } else {
+      // LogicalKeySizeInBits is the size of an EC public key. But an
+      // ECDSA signature length depends on the size of the base point's
+      // order. For P-256, P-384, and P-521, these two sizes are the same.
+      return ECDSA_SIG_max_len((cssm_key_->KeyHeader.LogicalKeySizeInBits + 7) /
+                               8);
+    }
+  }
+
+  Error SignDigest(SSLPrivateKey::Hash hash,
+                   const base::StringPiece& input,
+                   std::vector<uint8_t>* signature) override {
+    crypto::OpenSSLErrStackTracer tracer(FROM_HERE);
+
+    CSSM_CSP_HANDLE csp_handle;
+    OSStatus status = SecKeyGetCSPHandle(key_.get(), &csp_handle);
+    if (status != noErr) {
+      OSSTATUS_LOG(WARNING, status);
+      return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
+    }
+
+    const CSSM_ACCESS_CREDENTIALS* cssm_creds = nullptr;
+    status = SecKeyGetCredentials(key_.get(), CSSM_ACL_AUTHORIZATION_SIGN,
+                                  kSecCredentialTypeDefault, &cssm_creds);
+    if (status != noErr) {
+      OSSTATUS_LOG(WARNING, status);
+      return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
+    }
+
+    CSSM_CC_HANDLE* cssm_signature_raw = nullptr;
+    if (CSSM_CSP_CreateSignatureContext(
+            csp_handle, cssm_key_->KeyHeader.AlgorithmId, cssm_creds, cssm_key_,
+            &cssm_signature_raw) != CSSM_OK) {
+      return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
+    }
+    ScopedCSSM_CC_HANDLE cssm_signature(cssm_signature_raw);
+
+    CSSM_DATA hash_data;
+    hash_data.Length = input.size();
+    hash_data.Data =
+        const_cast<uint8_t*>(reinterpret_cast<const uint8_t*>(input.data()));
+
+    crypto::ScopedOpenSSLBytes free_digest_info;
+    if (cssm_key_->KeyHeader.AlgorithmId == CSSM_ALGID_RSA) {
+      // CSSM expects the caller to prepend the DigestInfo.
+      int hash_nid = NID_undef;
+      switch (hash) {
+        case SSLPrivateKey::Hash::MD5_SHA1:
+          hash_nid = NID_md5_sha1;
+          break;
+        case SSLPrivateKey::Hash::SHA1:
+          hash_nid = NID_sha1;
+          break;
+        case SSLPrivateKey::Hash::SHA256:
+          hash_nid = NID_sha256;
+          break;
+        case SSLPrivateKey::Hash::SHA384:
+          hash_nid = NID_sha384;
+          break;
+        case SSLPrivateKey::Hash::SHA512:
+          hash_nid = NID_sha512;
+          break;
+      }
+      DCHECK_NE(NID_undef, hash_nid);
+      int is_alloced;
+      if (!RSA_add_pkcs1_prefix(&hash_data.Data, &hash_data.Length, &is_alloced,
+                                hash_nid, hash_data.Data, hash_data.Length)) {
+        return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
+      }
+      if (is_alloced)
+        free_digest_info.reset(hash_data.Data);
+
+      // Set RSA blinding.
+      CSSM_CONTEXT_ATTRIBUTE blinding_attr;
+      blinding_attr.AttributeType = CSSM_ATTRIBUTE_RSA_BLINDING;
+      blinding_attr.AttributeLength = sizeof(uint32_t);
+      blinding_attr.Attribute.Uint32 = 1;
+      if (CSSM_UpdateContextAttributes(cssm_signature.get(), 1,
+                                       &blinding_attr) != CSSM_OK) {
+        return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
+      }
+    }
+
+    signature->resize(GetMaxSignatureLengthInBytes());
+    CSSM_DATA signature_data;
+    signature_data.Length = signature->size();
+    signature_data.Data = vector_as_array(signature);
+
+    if (CSSM_SignData(cssm_signature.get(), &hash_data, 1, CSSM_ALGID_NONE,
+                      &signature_data) != CSSM_OK) {
+      return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
+    }
+    signature->resize(signature_data.Length);
+    return OK;
+  }
+
+ private:
+  base::ScopedCFTypeRef<SecKeyRef> key_;
+  const CSSM_KEY* cssm_key_;
+
+  DISALLOW_COPY_AND_ASSIGN(SSLPlatformKeyMac);
+};
+
+}  // namespace
+
+scoped_ptr<SSLPrivateKey> FetchClientCertPrivateKey(
+    X509Certificate* certificate,
+    scoped_refptr<base::SequencedTaskRunner> task_runner) {
+  // Look up the private key.
+  base::ScopedCFTypeRef<SecKeyRef> private_key(
+      FetchSecKeyRefForCertificate(certificate));
+  if (!private_key)
+    return nullptr;
+
+  const CSSM_KEY* cssm_key;
+  OSStatus status = SecKeyGetCSSMKey(private_key.get(), &cssm_key);
+  if (status != noErr)
+    return nullptr;
+
+  if (cssm_key->KeyHeader.AlgorithmId != CSSM_ALGID_RSA &&
+      cssm_key->KeyHeader.AlgorithmId != CSSM_ALGID_ECDSA) {
+    LOG(ERROR) << "Unknown key type: " << cssm_key->KeyHeader.AlgorithmId;
+    return nullptr;
+  }
+  return make_scoped_ptr(new ThreadedSSLPrivateKey(
+      make_scoped_ptr(new SSLPlatformKeyMac(private_key.get(), cssm_key)),
+      task_runner.Pass()));
+}
+
+}  // namespace net