Add PPAPI interfaces for platform verification.

ppapi/api/private/ppb_platform_verification_private.idl

+/* Copyright 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.
+ */
+
+/**
+ * This file defines the API for platform verification. Currently, it only
+ * supports Chrome OS.
+ */
+
+[generate_thunk]
+
+label Chrome {
+  M31 = 0.1
+};
+
+/**
+ * The <code>PPB_PlatformVerification_Private</code> interface allows authorized
+ * services to verify that the underlying platform is trusted. An example of
+ * untrusted platform is a Chromebook in developer mode.

[ddorwin, 2013/09/06 05:58:28]

I think we should give an example of where we might get an affirmative answer:
s/un//
s/developer/verified boot/

[DaleCurtis, 2013/09/06 21:49:32]

Done.

+ */
+
+interface PPB_PlatformVerification_Private {
+  /**
+   * Create() creates a <code>PPB_PlatformVerification_Private</code> object.
+   *
+   * @pram[in] instance A <code>PP_Instance</code> identifying one instance of
+   * a module.
+   *
+   * @return A <code>PP_Resource</code> corresponding to a
+   * <code>PPB_PlatformVerification_Private</code> if successful, 0 if creation
+   * failed.
+   */
+  PP_Resource Create([in] PP_Instance instance);
+
+  /**
+   * IsPlatformVerification() determines if the provided resource is a
+   * <code>PPB_PlatformVerification_Private</code>.
+   *
+   * @param[in] resource A <code>PP_Resource</code> corresponding to a
+   * <code>PPB_PlatformVerification_Private</code>.
+   *
+   * @return <code>PP_TRUE</code> if the resource is a
+   * <code>PPB_PlatformVerification_Private</code>, <code>PP_FALSE</code> if the
+   * resource is invalid or some type other than
+   * <code>PPB_PlatformVerification_Private</code>.
+   */
+  PP_Bool IsPlatformVerification([in] PP_Resource resource);
+
+  /* Whether the platform can be challenged and is expected to pass.
+   */
+  PP_Bool CanChallengePlatform();

[ddorwin, 2013/09/06 05:58:28]

Maybe this was discussed elsewhere, but "CanChallenge" doesn't exactly convey
"should pass platform challenge". I guess maybe you "can't"/shouldn't challenge
it if the platform knows it will fail.

[DaleCurtis, 2013/09/06 21:49:32]

It was discussed on the the CDM.h CL. CanChallengePlatform() conveys enough of
that meaning without being overly verbose. The description also mentions that it
will only return true if the challenge is expected to pass.

+
+  /**
+   * Requests a platform challenge for a given service id.
+   *
+   * @param[in] service_id A <code>PP_Var</code> of type
+   * <code>PP_VARTYPE_STRING</code> containing the service_id for the challenge.
+   *
+   * @param[in] challenge A <code>PP_Var</code> of type
+   * <code>PP_VARTYPE_ARRAY_BUFFER</code> that contains the challenge data.
+   *
+   * @param[out] signed_data A <code>PP_Var</code> of type

[ddorwin, 2013/09/06 05:58:28]

I'm not clear on this one. Let's discuss.

[DaleCurtis, 2013/09/06 21:49:32]

Done. I've removed the implementation details.

+   * <code>PP_VARTYPE_ARRAY_BUFFER</code> that contains the combined challenge
+   * and nonce data signed by the platform.
+   *
+   * @param[in] signed_data_signature A <code>PP_Var</code> of type
+   * <code>PP_VARTYPE_ARRAY_BUFFER</code> that contains the signature of the
+   * signed data block.
+   *
+   * @param[in] platform_key_certificate A <code>PP_Var</code> of type
+   * <code>PP_VARTYPE_ARRAY_BUFFER</code> that contains the device specific
+   * certificate for the requested service_id.
+   *
+   * @param[in] callback A <code>PP_CompletionCallback</code> to be called after
+   * the platform challenge has been completed. This callback will only run if
+   * the return code is <code>PP_OK_COMPLETIONPENDING</code>.
+   *
+   * @return An int32_t containing an error code from <code>pp_errors.h</code>.
+   */
+  int32_t ChallengePlatform(
+      [in] PP_Instance instance,
+      [in] PP_Var service_id,
+      [in] PP_Var challenge,
+      [out] PP_Var signed_data,
+      [out] PP_Var signed_data_signature,
+      [out] PP_Var platform_key_certificate,
+      [in] PP_CompletionCallback callback);
+};