xref: /aosp_15_r20/external/sandboxed-api/sandboxed_api/var_lenval.h (revision ec63e07ab9515d95e79c211197c445ef84cefa6a)
1 // Copyright 2019 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef SANDBOXED_API_VAR_LENVAL_H_
16 #define SANDBOXED_API_VAR_LENVAL_H_
17 
18 #include <sys/types.h>
19 #include <sys/uio.h>
20 
21 #include <cstring>
22 #include <memory>
23 #include <string>
24 #include <vector>
25 
26 #include "absl/base/macros.h"
27 #include "absl/status/status.h"
28 #include "sandboxed_api/lenval_core.h"
29 #include "sandboxed_api/var_abstract.h"
30 #include "sandboxed_api/var_array.h"
31 #include "sandboxed_api/var_ptr.h"
32 #include "sandboxed_api/var_struct.h"
33 
34 namespace sapi::v {
35 
36 template <class T>
37 class Proto;
38 
39 // Length + value container. Represents a pointer to a LenValStruct inside the
40 // sandboxee which allows the bidirectional synchronization data structures with
41 // changing lengths (e.g. protobuf structures). You probably want to directly
42 // use protobufs as they are easier to handle.
43 class LenVal : public Var {
44  public:
LenVal(const char * data,uint64_t size)45   explicit LenVal(const char* data, uint64_t size)
46       : array_(const_cast<uint8_t*>(reinterpret_cast<const uint8_t*>(data)),
47                size),
48         struct_(size, nullptr) {}
49 
LenVal(const std::vector<uint8_t> & data)50   explicit LenVal(const std::vector<uint8_t>& data)
51       : array_(data.size()), struct_(data.size(), nullptr) {
52     memcpy(array_.GetData(), data.data(), data.size());
53   }
54 
LenVal(size_t size)55   explicit LenVal(size_t size) : array_(size), struct_(size, nullptr) {}
56 
GetType()57   Type GetType() const final { return Type::kLenVal; }
GetTypeString()58   std::string GetTypeString() const final { return "LengthValue"; }
ToString()59   std::string ToString() const final { return "LenVal"; }
60 
61   absl::Status ResizeData(RPCChannel* rpc_channel, size_t size);
GetDataSize()62   size_t GetDataSize() const { return struct_.data().size; }
GetData()63   uint8_t* GetData() const { return array_.GetData(); }
GetRemote()64   void* GetRemote() const final { return struct_.GetRemote(); }
65 
66  protected:
GetSize()67   size_t GetSize() const final { return 0; }
68 
69   absl::Status Allocate(RPCChannel* rpc_channel, bool automatic_free) override;
70   absl::Status Free(RPCChannel* rpc_channel) override;
71   absl::Status TransferToSandboxee(RPCChannel* rpc_channel, pid_t pid) override;
72   absl::Status TransferFromSandboxee(RPCChannel* rpc_channel,
73                                      pid_t pid) override;
74 
75   Array<uint8_t> array_;
76   Struct<LenValStruct> struct_;
77 
78   template <class T>
79   friend class Proto;
80 };
81 
82 }  // namespace sapi::v
83 
84 #endif  // SANDBOXED_API_VAR_LENVAL_H_
85