1 /*
2 * Copyright (C) 2024 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "host/commands/process_sandboxer/policies.h"
18
19 #include <linux/filter.h>
20 #include <linux/prctl.h>
21 #include <netinet/ip_icmp.h>
22 #include <netinet/tcp.h>
23 #include <sys/mman.h>
24 #include <sys/socket.h>
25 #include <sys/syscall.h>
26
27 #include <vector>
28
29 #include <sandboxed_api/sandbox2/allowlists/unrestricted_networking.h>
30 #include <sandboxed_api/sandbox2/policybuilder.h>
31 #include <sandboxed_api/sandbox2/util/bpf_helper.h>
32 #include <sandboxed_api/util/path.h>
33
34 namespace cuttlefish::process_sandboxer {
35
36 using sapi::file::JoinPath;
37
WebRtcOperatorPolicy(const HostInfo & host)38 sandbox2::PolicyBuilder WebRtcOperatorPolicy(const HostInfo& host) {
39 return BaselinePolicy(host, host.HostToolExe("webrtc_operator"))
40 .AddDirectory(host.log_dir, /* is_ro= */ false)
41 .AddDirectory(
42 JoinPath(host.host_artifacts_path, "usr", "share", "webrtc"))
43 .AddFile("/dev/urandom") // For libwebsockets
44 .AddFile(host.cuttlefish_config_path)
45 .AllowEventFd()
46 .AllowHandleSignals()
47 .AddPolicyOnSyscall(
48 __NR_madvise,
49 {ARG_32(2), JEQ32(MADV_WIPEONFORK, ALLOW), JEQ32(0xffffffff, ALLOW)})
50 .AddPolicyOnSyscall(__NR_prctl,
51 {ARG_32(0), JEQ32(PR_CAPBSET_READ, ALLOW)})
52 .AddPolicyOnSyscall(__NR_socket, {ARG_32(0), JEQ32(AF_INET, ALLOW)})
53 .AddPolicyOnSyscall(
54 __NR_setsockopt,
55 [](bpf_labels& labels) -> std::vector<sock_filter> {
56 return {ARG_32(1), // level
57 JEQ32(IPPROTO_ICMP,
58 JUMP(&labels, cf_webrtc_operator_setsockopt_icmp)),
59 JNE32(IPPROTO_TCP,
60 JUMP(&labels, cf_webrtc_operator_setsockopt_end)),
61 // IPPROTO_TCP
62 ARG_32(2), // optname
63 JEQ32(TCP_NODELAY, ALLOW),
64 JUMP(&labels, cf_webrtc_operator_setsockopt_end),
65 // IPPROTO_ICMP
66 LABEL(&labels, cf_webrtc_operator_setsockopt_icmp),
67 ARG_32(2), // optname
68 JEQ32(ICMP_REDIR_NETTOS, ALLOW),
69 LABEL(&labels, cf_webrtc_operator_setsockopt_end)};
70 })
71 .Allow(sandbox2::UnrestrictedNetworking())
72 .AllowSafeFcntl()
73 .AllowSyscall(__NR_accept)
74 .AllowSyscall(__NR_bind)
75 .AllowSyscall(__NR_getpeername)
76 .AllowSyscall(__NR_getsockname)
77 .AllowSyscall(__NR_listen)
78 .AllowTCGETS();
79 }
80
81 } // namespace cuttlefish::process_sandboxer
82