1 /*
2 * Copyright (c) 2021 Huawei Device Co., Ltd.
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 * http://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
16 #include <array>
17
18 #include "dgram_socket_server.h"
19
20 namespace OHOS {
21 namespace HiviewDFX {
RecvPacket(std::vector<char> & buffer,struct ucred * cred)22 int DgramSocketServer::RecvPacket(std::vector<char>& buffer, struct ucred *cred)
23 {
24 uint16_t packetLen = 0;
25 if (auto status = Recv(&packetLen, sizeof(packetLen)); status < 0) {
26 return status;
27 }
28 if (packetLen > maxPacketLength) {
29 Recv(&packetLen, sizeof(packetLen), 0); // skip too long packet
30 return 0;
31 }
32
33 std::array<char, CMSG_SPACE(sizeof(struct ucred))> control = {0};
34
35 struct msghdr msgh = {0};
36 int ret = 0;
37 if (cred != nullptr) {
38 struct iovec iov;
39 iov.iov_base = buffer.data();
40 iov.iov_len = packetLen;
41 msgh.msg_iov = &iov;
42 msgh.msg_iovlen = 1;
43
44 msgh.msg_control = control.data();
45 msgh.msg_controllen = control.size();
46
47 msgh.msg_name = nullptr;
48 msgh.msg_namelen = 0;
49 msgh.msg_flags = 0;
50
51 ret = RecvMsg(&msgh);
52 } else {
53 ret = Recv(buffer.data(), packetLen, 0);
54 }
55
56 if (ret <= 0) {
57 return ret;
58 } else if (cred != nullptr) {
59 struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msgh);
60 struct ucred *receivedUcred = (struct ucred*)CMSG_DATA(cmsg);
61 if (receivedUcred == nullptr) {
62 return 0;
63 }
64 *cred = *receivedUcred;
65 }
66 buffer[ret - 1] = 0;
67
68 return ret;
69 }
70 } // namespace HiviewDFX
71 } // namespace OHOS
72