Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012-2014 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 <sys/socket.h> |
| 18 | #include <sys/types.h> |
| 19 | #include <sys/un.h> |
| 20 | #include <unistd.h> |
| 21 | |
| 22 | #include <cutils/sockets.h> |
| 23 | #include <log/logger.h> |
| 24 | |
| 25 | #include "LogListener.h" |
| 26 | |
| 27 | LogListener::LogListener(LogBuffer *buf, LogReader *reader) |
| 28 | : SocketListener(getLogSocket(), false) |
| 29 | , logbuf(buf) |
| 30 | , reader(reader) |
| 31 | { } |
| 32 | |
| 33 | bool LogListener::onDataAvailable(SocketClient *cli) { |
Mark Salyzyn | b059cf5 | 2014-03-18 15:30:17 -0700 | [diff] [blame] | 34 | char buffer[sizeof_log_id_t + sizeof(log_time) + sizeof(char) |
| 35 | + LOGGER_ENTRY_MAX_PAYLOAD]; |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 36 | struct iovec iov = { buffer, sizeof(buffer) }; |
| 37 | memset(buffer, 0, sizeof(buffer)); |
| 38 | |
| 39 | char control[CMSG_SPACE(sizeof(struct ucred))]; |
| 40 | struct msghdr hdr = { |
| 41 | NULL, |
| 42 | 0, |
| 43 | &iov, |
| 44 | 1, |
| 45 | control, |
| 46 | sizeof(control), |
| 47 | 0, |
| 48 | }; |
| 49 | |
| 50 | int socket = cli->getSocket(); |
| 51 | |
| 52 | ssize_t n = recvmsg(socket, &hdr, 0); |
Mark Salyzyn | dbb708a | 2014-03-21 14:37:06 -0700 | [diff] [blame] | 53 | if (n <= (ssize_t)(sizeof_log_id_t + sizeof(uint16_t) + sizeof(log_time))) { |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 54 | return false; |
| 55 | } |
| 56 | |
| 57 | struct ucred *cred = NULL; |
| 58 | |
| 59 | struct cmsghdr *cmsg = CMSG_FIRSTHDR(&hdr); |
| 60 | while (cmsg != NULL) { |
| 61 | if (cmsg->cmsg_level == SOL_SOCKET |
| 62 | && cmsg->cmsg_type == SCM_CREDENTIALS) { |
| 63 | cred = (struct ucred *)CMSG_DATA(cmsg); |
| 64 | break; |
| 65 | } |
| 66 | cmsg = CMSG_NXTHDR(&hdr, cmsg); |
| 67 | } |
| 68 | |
| 69 | if (cred == NULL) { |
| 70 | return false; |
| 71 | } |
| 72 | |
| 73 | if (cred->uid == getuid()) { |
| 74 | // ignore log messages we send to ourself. |
| 75 | // Such log messages are often generated by libraries we depend on |
| 76 | // which use standard Android logging. |
| 77 | return false; |
| 78 | } |
| 79 | |
| 80 | // First log element is always log_id. |
| 81 | log_id_t log_id = (log_id_t) *((typeof_log_id_t *) buffer); |
| 82 | if (log_id < 0 || log_id >= LOG_ID_MAX) { |
| 83 | return false; |
| 84 | } |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 85 | char *msg = ((char *)buffer) + sizeof_log_id_t; |
| 86 | n -= sizeof_log_id_t; |
| 87 | |
Mark Salyzyn | b992d0d | 2014-03-20 16:09:38 -0700 | [diff] [blame] | 88 | // second element is the thread id of the caller |
| 89 | pid_t tid = (pid_t) *((uint16_t *) msg); |
| 90 | msg += sizeof(uint16_t); |
| 91 | n -= sizeof(uint16_t); |
| 92 | |
| 93 | // third element is the realtime at point of caller |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 94 | log_time realtime(msg); |
| 95 | msg += sizeof(log_time); |
| 96 | n -= sizeof(log_time); |
| 97 | |
Mark Salyzyn | 22e287d | 2014-03-21 13:12:16 -0700 | [diff] [blame] | 98 | // NB: hdr.msg_flags & MSG_TRUNC is not tested, silently passing a |
| 99 | // truncated message to the logs. |
| 100 | unsigned short len = n; // cap to internal maximum |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 101 | if (len == n) { |
Mark Salyzyn | b992d0d | 2014-03-20 16:09:38 -0700 | [diff] [blame] | 102 | logbuf->log(log_id, realtime, cred->uid, cred->pid, tid, msg, len); |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 103 | reader->notifyNewLog(); |
| 104 | } |
| 105 | |
| 106 | return true; |
| 107 | } |
| 108 | |
| 109 | int LogListener::getLogSocket() { |
Mark Salyzyn | dfc47e8 | 2014-03-24 10:26:47 -0700 | [diff] [blame^] | 110 | static const char socketName[] = "logdw"; |
| 111 | int sock = android_get_control_socket(socketName); |
| 112 | |
| 113 | if (sock < 0) { |
| 114 | sock = socket_local_server(socketName, |
| 115 | ANDROID_SOCKET_NAMESPACE_RESERVED, |
| 116 | SOCK_DGRAM); |
| 117 | } |
| 118 | |
Mark Salyzyn | 0175b07 | 2014-02-26 09:50:16 -0800 | [diff] [blame] | 119 | int on = 1; |
| 120 | if (setsockopt(sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) { |
| 121 | return -1; |
| 122 | } |
| 123 | return sock; |
| 124 | } |