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Diffstat (limited to 'sandbox/src/registry_policy.cc')
| -rw-r--r-- | sandbox/src/registry_policy.cc | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/sandbox/src/registry_policy.cc b/sandbox/src/registry_policy.cc new file mode 100644 index 0000000..497636f --- /dev/null +++ b/sandbox/src/registry_policy.cc @@ -0,0 +1,227 @@ +// Copyright (c) 2006-2008 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 <string> + +#include "sandbox/src/registry_policy.h" + +#include "base/logging.h" +#include "sandbox/src/ipc_tags.h" +#include "sandbox/src/policy_engine_opcodes.h" +#include "sandbox/src/policy_params.h" +#include "sandbox/src/sandbox_utils.h" +#include "sandbox/src/sandbox_types.h" +#include "sandbox/src/win_utils.h" + +namespace { + +static const DWORD kAllowedRegFlags = KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS | + KEY_NOTIFY | KEY_READ | GENERIC_READ | + GENERIC_EXECUTE | READ_CONTROL; + +// Opens the key referenced by |obj_attributes| with |access| and +// checks what permission was given. Remove the WRITE flags and update +// |access| with the new value. +NTSTATUS TranslateMaximumAllowed(OBJECT_ATTRIBUTES* obj_attributes, + DWORD* access) { + NtOpenKeyFunction NtOpenKey = NULL; + ResolveNTFunctionPtr("NtOpenKey", &NtOpenKey); + + NtCloseFunction NtClose = NULL; + ResolveNTFunctionPtr("NtClose", &NtClose); + + NtQueryObjectFunction NtQueryObject = NULL; + ResolveNTFunctionPtr("NtQueryObject", &NtQueryObject); + + // Open the key. + HANDLE handle; + NTSTATUS status = NtOpenKey(&handle, *access, obj_attributes); + if (!NT_SUCCESS(status)) + return status; + + OBJECT_BASIC_INFORMATION info = {0}; + status = NtQueryObject(handle, ObjectBasicInformation, &info, sizeof(info), + NULL); + NtClose(handle); + if (!NT_SUCCESS(status)) + return status; + + *access = info.GrantedAccess & kAllowedRegFlags; + return STATUS_SUCCESS; +} + +NTSTATUS NtCreateKeyInTarget(HANDLE* target_key_handle, + ACCESS_MASK desired_access, + OBJECT_ATTRIBUTES* obj_attributes, + ULONG title_index, + UNICODE_STRING* class_name, + ULONG create_options, + ULONG* disposition, + HANDLE target_process) { + NtCreateKeyFunction NtCreateKey = NULL; + ResolveNTFunctionPtr("NtCreateKey", &NtCreateKey); + + if (MAXIMUM_ALLOWED & desired_access) { + NTSTATUS status = TranslateMaximumAllowed(obj_attributes, &desired_access); + if (!NT_SUCCESS(status)) + return STATUS_ACCESS_DENIED; + } + + HANDLE local_handle = INVALID_HANDLE_VALUE; + NTSTATUS status = NtCreateKey(&local_handle, desired_access, obj_attributes, + title_index, class_name, create_options, + disposition); + if (!NT_SUCCESS(status)) + return status; + + if (!::DuplicateHandle(::GetCurrentProcess(), local_handle, + target_process, target_key_handle, 0, FALSE, + DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS)) { + ::CloseHandle(local_handle); + return STATUS_ACCESS_DENIED; + } + return STATUS_SUCCESS; +} + +NTSTATUS NtOpenKeyInTarget(HANDLE* target_key_handle, + ACCESS_MASK desired_access, + OBJECT_ATTRIBUTES* obj_attributes, + HANDLE target_process) { + NtOpenKeyFunction NtOpenKey = NULL; + ResolveNTFunctionPtr("NtOpenKey", &NtOpenKey); + + if (MAXIMUM_ALLOWED & desired_access) { + NTSTATUS status = TranslateMaximumAllowed(obj_attributes, &desired_access); + if (!NT_SUCCESS(status)) + return STATUS_ACCESS_DENIED; + } + + HANDLE local_handle = INVALID_HANDLE_VALUE; + NTSTATUS status = NtOpenKey(&local_handle, desired_access, obj_attributes); + + if (!NT_SUCCESS(status)) + return status; + + if (!::DuplicateHandle(::GetCurrentProcess(), local_handle, + target_process, target_key_handle, 0, FALSE, + DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS)) { + ::CloseHandle(local_handle); + return STATUS_ACCESS_DENIED; + } + return STATUS_SUCCESS; +} + +} + +namespace sandbox { + +bool RegistryPolicy::GenerateRules(const wchar_t* name, + TargetPolicy::Semantics semantics, + LowLevelPolicy* policy) { + std::wstring resovled_name(name); + if (resovled_name.empty()) { + return false; + } + + if (!ResolveRegistryName(resovled_name, &resovled_name)) + return false; + + name = resovled_name.c_str(); + + EvalResult result = ASK_BROKER; + + PolicyRule open(result); + PolicyRule create(result); + + switch (semantics) { + case TargetPolicy::REG_ALLOW_READONLY: { + // We consider all flags that are not known to be readonly as potentially + // used for write. Here we also support MAXIMUM_ALLOWED, but we are going + // to expand it to read-only before the call. + DWORD restricted_flags = ~(kAllowedRegFlags | MAXIMUM_ALLOWED); + open.AddNumberMatch(IF_NOT, OpenKey::ACCESS, restricted_flags, AND); + create.AddNumberMatch(IF_NOT, OpenKey::ACCESS, restricted_flags, AND); + break; + } + case TargetPolicy::REG_ALLOW_ANY: { + break; + } + default: { + NOTREACHED(); + return false; + } + } + + if (!create.AddStringMatch(IF, OpenKey::NAME, name, CASE_INSENSITIVE) || + !policy->AddRule(IPC_NTCREATEKEY_TAG, &create)) { + return false; + } + + if (!open.AddStringMatch(IF, OpenKey::NAME, name, CASE_INSENSITIVE) || + !policy->AddRule(IPC_NTOPENKEY_TAG, &open)) { + return false; + } + + return true; +} + +bool RegistryPolicy::CreateKeyAction(EvalResult eval_result, + const ClientInfo& client_info, + const std::wstring &key, + uint32 attributes, + HANDLE root_directory, + uint32 desired_access, + uint32 title_index, + uint32 create_options, + HANDLE* handle, + NTSTATUS* nt_status, + ULONG* disposition) { + // The only action supported is ASK_BROKER which means create the requested + // file as specified. + if (ASK_BROKER != eval_result) { + *nt_status = STATUS_ACCESS_DENIED; + return false; + } + + // We don't support creating link keys, volatile keys or backup/restore. + if (create_options) { + *nt_status = STATUS_ACCESS_DENIED; + return false; + } + + UNICODE_STRING uni_name = {0}; + OBJECT_ATTRIBUTES obj_attributes = {0}; + InitObjectAttribs(key, attributes, root_directory, &obj_attributes, + &uni_name); + *nt_status = NtCreateKeyInTarget(handle, desired_access, &obj_attributes, + title_index, NULL, create_options, + disposition, client_info.process); + return true; +} + +bool RegistryPolicy::OpenKeyAction(EvalResult eval_result, + const ClientInfo& client_info, + const std::wstring &key, + uint32 attributes, + HANDLE root_directory, + uint32 desired_access, + HANDLE* handle, + NTSTATUS* nt_status) { + // The only action supported is ASK_BROKER which means open the requested + // file as specified. + if (ASK_BROKER != eval_result) { + *nt_status = STATUS_ACCESS_DENIED; + return true; + } + + UNICODE_STRING uni_name = {0}; + OBJECT_ATTRIBUTES obj_attributes = {0}; + InitObjectAttribs(key, attributes, root_directory, &obj_attributes, + &uni_name); + *nt_status = NtOpenKeyInTarget(handle, desired_access, &obj_attributes, + client_info.process); + return true; +} + +} // namespace sandbox |