Chenbo Feng | baede73 | 2017-10-25 12:31:43 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2017, 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 | |
Elliott Hughes | 8e9aeb9 | 2017-11-10 10:22:07 -0800 | [diff] [blame] | 17 | #include <cutils/qtaguid.h> |
| 18 | |
Chenbo Feng | baede73 | 2017-10-25 12:31:43 -0700 | [diff] [blame] | 19 | // #define LOG_NDEBUG 0 |
| 20 | |
| 21 | #define LOG_TAG "qtaguid" |
| 22 | |
| 23 | #include <dlfcn.h> |
| 24 | #include <errno.h> |
| 25 | #include <fcntl.h> |
| 26 | #include <inttypes.h> |
| 27 | #include <stdio.h> |
| 28 | #include <string.h> |
| 29 | #include <unistd.h> |
| 30 | |
Chenbo Feng | baede73 | 2017-10-25 12:31:43 -0700 | [diff] [blame] | 31 | #include <log/log.h> |
| 32 | |
| 33 | class netdHandler { |
| 34 | public: |
| 35 | int (*netdTagSocket)(int, uint32_t, uid_t); |
| 36 | int (*netdUntagSocket)(int); |
| 37 | int (*netdSetCounterSet)(uint32_t, uid_t); |
| 38 | int (*netdDeleteTagData)(uint32_t, uid_t); |
| 39 | }; |
| 40 | |
| 41 | int dummyTagSocket(int, uint32_t, uid_t) { |
| 42 | return -EREMOTEIO; |
| 43 | } |
| 44 | |
| 45 | int dummyUntagSocket(int) { |
| 46 | return -EREMOTEIO; |
| 47 | } |
| 48 | |
| 49 | int dummySetCounterSet(uint32_t, uid_t) { |
| 50 | return -EREMOTEIO; |
| 51 | } |
| 52 | |
| 53 | int dummyDeleteTagData(uint32_t, uid_t) { |
| 54 | return -EREMOTEIO; |
| 55 | } |
| 56 | |
| 57 | netdHandler initHandler(void) { |
| 58 | netdHandler handler = {dummyTagSocket, dummyUntagSocket, dummySetCounterSet, dummyDeleteTagData}; |
| 59 | |
| 60 | void* netdClientHandle = dlopen("libnetd_client.so", RTLD_NOW); |
| 61 | if (!netdClientHandle) { |
| 62 | ALOGE("Failed to open libnetd_client.so: %s", dlerror()); |
| 63 | return handler; |
| 64 | } |
| 65 | |
| 66 | handler.netdTagSocket = (int (*)(int, uint32_t, uid_t))dlsym(netdClientHandle, "tagSocket"); |
| 67 | if (!handler.netdTagSocket) { |
| 68 | ALOGE("load netdTagSocket handler failed: %s", dlerror()); |
| 69 | } |
| 70 | |
| 71 | handler.netdUntagSocket = (int (*)(int))dlsym(netdClientHandle, "untagSocket"); |
| 72 | if (!handler.netdUntagSocket) { |
| 73 | ALOGE("load netdUntagSocket handler failed: %s", dlerror()); |
| 74 | } |
| 75 | |
| 76 | handler.netdSetCounterSet = (int (*)(uint32_t, uid_t))dlsym(netdClientHandle, "setCounterSet"); |
| 77 | if (!handler.netdSetCounterSet) { |
| 78 | ALOGE("load netdSetCounterSet handler failed: %s", dlerror()); |
| 79 | } |
| 80 | |
| 81 | handler.netdDeleteTagData = (int (*)(uint32_t, uid_t))dlsym(netdClientHandle, "deleteTagData"); |
| 82 | if (!handler.netdDeleteTagData) { |
| 83 | ALOGE("load netdDeleteTagData handler failed: %s", dlerror()); |
| 84 | } |
| 85 | return handler; |
| 86 | } |
| 87 | |
| 88 | // The language guarantees that this object will be initialized in a thread-safe way. |
| 89 | static netdHandler& getHandler() { |
| 90 | static netdHandler instance = initHandler(); |
| 91 | return instance; |
| 92 | } |
| 93 | |
| 94 | int qtaguid_tagSocket(int sockfd, int tag, uid_t uid) { |
| 95 | // Check the socket fd passed to us is still valid before we load the netd |
| 96 | // client. Pass a already closed socket fd to netd client may let netd open |
| 97 | // the unix socket with the same fd number and pass it to server for |
| 98 | // tagging. |
| 99 | // TODO: move the check into netdTagSocket. |
| 100 | int res = fcntl(sockfd, F_GETFD); |
| 101 | if (res < 0) return res; |
| 102 | |
| 103 | ALOGV("Tagging socket %d with tag %u for uid %d", sockfd, tag, uid); |
| 104 | return getHandler().netdTagSocket(sockfd, tag, uid); |
| 105 | } |
| 106 | |
| 107 | int qtaguid_untagSocket(int sockfd) { |
| 108 | // Similiar to tag socket. We need a check before untag to make sure untag a closed socket fail |
| 109 | // as expected. |
| 110 | // TODO: move the check into netdTagSocket. |
| 111 | int res = fcntl(sockfd, F_GETFD); |
| 112 | if (res < 0) return res; |
| 113 | |
| 114 | ALOGV("Untagging socket %d", sockfd); |
| 115 | return getHandler().netdUntagSocket(sockfd); |
| 116 | } |
| 117 | |
| 118 | int qtaguid_setCounterSet(int counterSetNum, uid_t uid) { |
| 119 | ALOGV("Setting counters to set %d for uid %d", counterSetNum, uid); |
| 120 | return getHandler().netdSetCounterSet(counterSetNum, uid); |
| 121 | } |
| 122 | |
| 123 | int qtaguid_deleteTagData(int tag, uid_t uid) { |
| 124 | ALOGV("Deleting tag data with tag %u for uid %d", tag, uid); |
| 125 | return getHandler().netdDeleteTagData(tag, uid); |
| 126 | } |