1 /* 2 * Copyright 2016, 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 "util.h" 18 19 #include <sys/socket.h> 20 21 #include <string> 22 #include <utility> 23 24 #include <android-base/file.h> 25 #include <android-base/stringprintf.h> 26 #include <android-base/strings.h> 27 #include <android-base/unique_fd.h> 28 #include <cutils/sockets.h> 29 #include "protocol.h" 30 31 using android::base::unique_fd; 32 33 ssize_t send_fd(int sockfd, const void* data, size_t len, unique_fd fd) { 34 char cmsg_buf[CMSG_SPACE(sizeof(int))]; 35 36 iovec iov = { .iov_base = const_cast<void*>(data), .iov_len = len }; 37 msghdr msg = { 38 .msg_iov = &iov, .msg_iovlen = 1, .msg_control = cmsg_buf, .msg_controllen = sizeof(cmsg_buf), 39 }; 40 auto cmsg = CMSG_FIRSTHDR(&msg); 41 cmsg->cmsg_level = SOL_SOCKET; 42 cmsg->cmsg_type = SCM_RIGHTS; 43 cmsg->cmsg_len = CMSG_LEN(sizeof(int)); 44 *reinterpret_cast<int*>(CMSG_DATA(cmsg)) = fd.get(); 45 46 return TEMP_FAILURE_RETRY(sendmsg(sockfd, &msg, 0)); 47 } 48 49 ssize_t recv_fd(int sockfd, void* _Nonnull data, size_t len, unique_fd* _Nullable out_fd) { 50 char cmsg_buf[CMSG_SPACE(sizeof(int))]; 51 52 iovec iov = { .iov_base = const_cast<void*>(data), .iov_len = len }; 53 msghdr msg = { 54 .msg_iov = &iov, 55 .msg_iovlen = 1, 56 .msg_control = cmsg_buf, 57 .msg_controllen = sizeof(cmsg_buf), 58 .msg_flags = 0, 59 }; 60 auto cmsg = CMSG_FIRSTHDR(&msg); 61 cmsg->cmsg_level = SOL_SOCKET; 62 cmsg->cmsg_type = SCM_RIGHTS; 63 cmsg->cmsg_len = CMSG_LEN(sizeof(int)); 64 65 ssize_t result = TEMP_FAILURE_RETRY(recvmsg(sockfd, &msg, 0)); 66 if (result == -1) { 67 return -1; 68 } 69 70 unique_fd fd; 71 bool received_fd = msg.msg_controllen == sizeof(cmsg_buf); 72 if (received_fd) { 73 fd.reset(*reinterpret_cast<int*>(CMSG_DATA(cmsg))); 74 } 75 76 if ((msg.msg_flags & MSG_TRUNC) != 0) { 77 errno = EFBIG; 78 return -1; 79 } else if ((msg.msg_flags & MSG_CTRUNC) != 0) { 80 errno = ERANGE; 81 return -1; 82 } 83 84 if (out_fd) { 85 *out_fd = std::move(fd); 86 } else if (received_fd) { 87 errno = ERANGE; 88 return -1; 89 } 90 91 return result; 92 } 93 94 std::string get_process_name(pid_t pid) { 95 std::string result = "<unknown>"; 96 android::base::ReadFileToString(android::base::StringPrintf("/proc/%d/cmdline", pid), &result); 97 return result; 98 } 99 100 std::string get_thread_name(pid_t tid) { 101 std::string result = "<unknown>"; 102 android::base::ReadFileToString(android::base::StringPrintf("/proc/%d/comm", tid), &result); 103 return android::base::Trim(result); 104 } 105
