1 // Copyright 2020 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 #include <libgen.h>
16 #include <syscall.h>
17
18 #include <cstdlib>
19 #include <iostream>
20
21 #include "jsonnet_sapi.sapi.h" // NOLINT(build/include)
22 #include "absl/flags/parse.h"
23 #include "absl/log/check.h"
24 #include "absl/log/globals.h"
25 #include "absl/log/initialize.h"
26 #include "sandboxed_api/util/fileops.h"
27 #include "sandboxed_api/util/path.h"
28
29 class JsonnetSapiSandbox : public JsonnetSandbox {
30 public:
JsonnetSapiSandbox(std::string in_file,std::string out_file)31 explicit JsonnetSapiSandbox(std::string in_file, std::string out_file)
32 : in_file_(std::move(in_file)), out_file_(std::move(out_file)) {}
33
34 // We need only the input file here, not the whole input directory
ModifyPolicy(sandbox2::PolicyBuilder *)35 std::unique_ptr<sandbox2::Policy> ModifyPolicy(
36 sandbox2::PolicyBuilder*) override {
37 return sandbox2::PolicyBuilder()
38 .AllowStaticStartup()
39 .AllowOpen()
40 .AllowRead()
41 .AllowWrite()
42 .AllowStat()
43 .AllowSystemMalloc()
44 .AllowExit()
45 .AllowSyscalls({
46 __NR_futex,
47 __NR_close,
48 })
49 .AddDirectoryAt(dirname(&out_file_[0]), "/output", /*is_ro=*/false)
50 .AddFile(in_file_, true)
51 .BuildOrDie();
52 }
53
54 private:
55 std::string in_file_;
56 std::string out_file_;
57 };
58
JsonnetMain(std::string in_file,std::string out_file)59 absl::Status JsonnetMain(std::string in_file, std::string out_file) {
60 using sapi::file::JoinPath;
61 using sapi::file_util::fileops::Basename;
62
63 // Initialize sandbox.
64 JsonnetSapiSandbox sandbox(in_file, out_file);
65 SAPI_RETURN_IF_ERROR(sandbox.Init());
66
67 JsonnetApi api(&sandbox);
68
69 // Initialize library's main structure.
70 SAPI_ASSIGN_OR_RETURN(JsonnetVm * jsonnet_vm, api.c_jsonnet_make());
71 sapi::v::RemotePtr vm_pointer(jsonnet_vm);
72
73 // Read input file.
74 std::string in_file_in_sandboxee(JoinPath("/input", Basename(in_file)));
75 sapi::v::ConstCStr in_file_var(in_file_in_sandboxee.c_str());
76 SAPI_ASSIGN_OR_RETURN(char* input,
77 api.c_read_input(false, in_file_var.PtrBefore()));
78
79 // Process jsonnet data.
80 sapi::v::RemotePtr input_pointer(input);
81 sapi::v::Int error;
82 SAPI_ASSIGN_OR_RETURN(char* output, api.c_jsonnet_fmt_snippet(
83 &vm_pointer, in_file_var.PtrBefore(),
84 &input_pointer, error.PtrAfter()));
85
86 CHECK(!error.GetValue()) << "Jsonnet code evaluation failed: "
87 << error.GetValue() << "\n";
88
89 // Write data to file.
90 std::string out_file_in_sandboxee(JoinPath("/output", Basename(out_file)));
91 sapi::v::ConstCStr out_file_var(out_file_in_sandboxee.c_str());
92 sapi::v::RemotePtr output_pointer(output);
93
94 SAPI_ASSIGN_OR_RETURN(
95 bool success,
96 api.c_write_output_file(&output_pointer, out_file_var.PtrBefore()));
97 CHECK(success) << "Writing to output file failed: " << success;
98
99 // Clean up.
100 SAPI_ASSIGN_OR_RETURN(char* result,
101 api.c_jsonnet_realloc(&vm_pointer, &output_pointer, 0));
102 SAPI_RETURN_IF_ERROR(api.c_jsonnet_destroy(&vm_pointer));
103 SAPI_RETURN_IF_ERROR(api.c_free_input(&input_pointer));
104
105 return absl::OkStatus();
106 }
107
main(int argc,char * argv[])108 int main(int argc, char* argv[]) {
109 using sapi::file_util::fileops::Basename;
110
111 absl::SetStderrThreshold(absl::LogSeverityAtLeast::kInfo);
112 absl::ParseCommandLine(argc, argv);
113 absl::InitializeLog();
114
115 if (argc != 3) {
116 std::cerr << "Usage:\n"
117 << Basename(argv[0])
118 << " /absolute/path/to/INPUT.jsonnet /absolute/path/to/OUTPUT\n";
119 return EXIT_FAILURE;
120 }
121
122 std::string in_file(argv[1]);
123 std::string out_file(argv[2]);
124
125 absl::Status status = JsonnetMain(in_file, out_file);
126 if (!status.ok()) {
127 LOG(ERROR) << "Failed: " << status.ToString();
128 return EXIT_FAILURE;
129 }
130
131 return EXIT_SUCCESS;
132 }
133