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* Copyright © 2014 Canonical Ltd.
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* This program is free software: you can redistribute it and/or modify it
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* under the terms of the GNU Lesser General Public License version 3,
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* as published by the Free Software Foundation.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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* Authored by: Thomas Voß <thomas.voss@canonical.com>
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#ifndef CORE_TRUST_MIR_MIR_AGENT_H_
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#define CORE_TRUST_MIR_MIR_AGENT_H_
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#include <core/trust/agent.h>
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#include <core/posix/child_process.h>
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#include <core/posix/exec.h>
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#include <mirclient/mir_toolkit/mir_client_library.h>
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#include <mirclient/mir_toolkit/mir_prompt_session.h>
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#include <condition_variable>
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// We wrap the Mir prompt session API into a struct to
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// ease with testing and mocking.
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struct CORE_TRUST_DLL_PUBLIC PromptSessionVirtualTable
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// Just a convenience typedef
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typedef std::shared_ptr<PromptSessionVirtualTable> Ptr;
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// Just a helper struct to be passed to client_fd_callbacks.
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// Marks the value of an invalid fd.
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static constexpr const int invalid_fd{-1};
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// The fd contained within this context instance.
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// Invoked whenever a request for creation of pre-authenticated fds succeeds.
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static void mir_client_fd_callback(MirPromptSession */*prompt_session*/, size_t count, int const* fds, void* context);
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// Create a MirPromptSessionVirtualTable for a given prompt session instance.
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// Please note that no change of ownwership is happening here. Instead, we expect
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// the calling code to handle object lifetimes.
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PromptSessionVirtualTable(MirPromptSession* prompt_session);
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virtual ~PromptSessionVirtualTable() = default;
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// Requests a new, pre-authenticated fd for associating prompt providers.
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// Returns the fd or throws std::runtime_error.
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virtual int new_fd_for_prompt_provider();
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// Finalizes and releases the given prompt session instance.
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virtual void release_sync();
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// The underlying prompt session instance.
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MirPromptSession* prompt_session;
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struct CORE_TRUST_DLL_PUBLIC ConnectionVirtualTable
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// Just a convenience typedef
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typedef std::shared_ptr<ConnectionVirtualTable> Ptr;
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// Create a new instance of MirConnectionVirtualTable
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// using a pre-existing connection to Mir. Please note
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// that we do not take ownership of the MirConnection but
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// expect the calling code to coordinate object lifetimes.
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ConnectionVirtualTable(MirConnection* connection);
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virtual ~ConnectionVirtualTable() = default;
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// Creates a new trusted prompt session instance synchronously.
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virtual PromptSessionVirtualTable::Ptr create_prompt_session_sync(
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// The process id of the requesting app/service
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// Callback handling prompt session state changes.
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mir_prompt_session_state_change_callback cb,
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// We do not take over ownership of the connection object.
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MirConnection* connection;
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// Abstracts common functionality required for running external helpers.
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struct CORE_TRUST_DLL_PUBLIC PromptProviderHelper
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// Just a convenience typedef.
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typedef std::shared_ptr<PromptProviderHelper> Ptr;
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// Creation-time arguments.
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struct CreationArguments
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// Path to the helper executable that provides the prompting UI.
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std::string path_to_helper_executable;
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// Invocation arguments for exec_prompt_provider_with_arguments
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struct InvocationArguments
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// The pre-authenticated fd that the helper
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// should use for connecting to Mir.
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// The application id of the requesting app.
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std::string application_id;
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// The extended description that should be presented to the user.
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std::string description;
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PromptProviderHelper(const CreationArguments& args);
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virtual ~PromptProviderHelper() = default;
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// Execs the executable provided at construction time for the arguments and
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// returns the corresponding child process.
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virtual core::posix::ChildProcess exec_prompt_provider_with_arguments(const InvocationArguments& args);
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// We store all arguments passed at construction.
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CreationArguments creation_arguments;
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// Implements the trust::Agent interface and dispatches calls to a helper
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// prompt provider, tying it together with the requesting service and app
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// by leveraging Mir's trusted session/prompting support.
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struct CORE_TRUST_DLL_PUBLIC Agent : public core::trust::Agent
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// Convenience typedef
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typedef std::shared_ptr<Agent> Ptr;
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// Helper struct for injecting state into on_trust_changed_state_state callbacks.
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// Used in prompt_user_for_request to wait for the trust session to be stopped.
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struct OnTrustSessionStateChangedCallbackContext
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// The process that provides the prompting UI.
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core::posix::ChildProcess prompt_provider_process;
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// Handles state changes of trust sessions and sigkills the child process
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// provided in context (of type OnTrustSessionStateChangedCallbackContext).
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static void on_trust_session_changed_state(
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// The prompt session instance that just changed state.
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MirPromptSession* prompt_provider,
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// The new state of the prompt session instance.
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MirPromptSessionState state,
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// The context of type context.
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// Returns a wait result -> trust::Request::Answer translator that only returns Answer::granted if
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// the prompt provider child process exits cleanly with status success.
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// Throws std::logic_error if the process did not exit but was signaled.
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static std::function<core::trust::Request::Answer(const core::posix::wait::Result&)> translator_only_accepting_exit_status_success();
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// Creates a new MirAgent instance with the given MirConnectionVirtualTable instance.
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// VTable object providing access to Mir's trusted prompting functionality.
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const ConnectionVirtualTable::Ptr& connection_vtable,
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// Exec helper for starting up prompt provider child processes with the correct setup
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// of command line arguments and environment variables.
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const PromptProviderHelper::Ptr& exec_helper,
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// A translator function for mapping child process exit states to trust::Request answers.
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const std::function<core::trust::Request::Answer(const core::posix::wait::Result&)>& translator);
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// From core::trust::Agent:
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// Throws a std::logic_error if anything unforeseen happens during execution, thus
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// indicating that no conclusive answer could be obtained from the user.
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core::trust::Request::Answer prompt_user_for_request(pid_t app_pid, const std::string& app_id, const std::string& description) override;
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// The connection VTable used for creating trusted prompting sessions.
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ConnectionVirtualTable::Ptr connection_vtable;
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// Execution helper for firing up prompt provider executables.
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PromptProviderHelper::Ptr exec_helper;
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// Translator instance.
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std::function<core::trust::Request::Answer(const core::posix::wait::Result&)> translator;
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CORE_TRUST_DLL_PUBLIC bool operator==(const PromptProviderHelper::InvocationArguments&, const PromptProviderHelper::InvocationArguments&);
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#endif // CORE_TRUST_MIR_MIR_AGENT_H_
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removed
src/core/trust/mir/agent.h
