1 /*
2  * Copyright (C) 2018 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 "QuotaUtils.h"
18 
19 #include <fstream>
20 #include <unordered_map>
21 
22 #include <sys/quota.h>
23 
24 #include <android-base/logging.h>
25 
26 #include "utils.h"
27 
28 namespace android {
29 namespace installd {
30 
31 namespace {
32 
33 std::recursive_mutex mMountsLock;
34 
35 /* Map of all quota mounts from target to source */
36 std::unordered_map<std::string, std::string> mQuotaReverseMounts;
37 
FindQuotaDeviceForUuid(const std::string & uuid)38 std::string& FindQuotaDeviceForUuid(const std::string& uuid) {
39     std::lock_guard<std::recursive_mutex> lock(mMountsLock);
40     auto path = create_data_path(uuid.empty() ? nullptr : uuid.c_str());
41     return mQuotaReverseMounts[path];
42 }
43 
44 } // namespace
45 
InvalidateQuotaMounts()46 bool InvalidateQuotaMounts() {
47     std::lock_guard<std::recursive_mutex> lock(mMountsLock);
48 
49     mQuotaReverseMounts.clear();
50 
51     std::ifstream in("/proc/mounts");
52     if (!in.is_open()) {
53         return false;
54     }
55 
56     std::string source;
57     std::string target;
58     std::string ignored;
59     while (!in.eof()) {
60         std::getline(in, source, ' ');
61         std::getline(in, target, ' ');
62         std::getline(in, ignored);
63 
64         if (target.compare(0, 13, "/data_mirror/") == 0) {
65             continue;
66         }
67 
68         if (source.compare(0, 11, "/dev/block/") == 0) {
69             struct dqblk dq;
70             if (quotactl(QCMD(Q_GETQUOTA, USRQUOTA), source.c_str(), 0,
71                     reinterpret_cast<char*>(&dq)) == 0) {
72                 LOG(DEBUG) << "Found quota mount " << source << " at " << target;
73                 mQuotaReverseMounts[target] = source;
74             }
75         }
76     }
77     return true;
78 }
79 
IsQuotaSupported(const std::string & uuid)80 bool IsQuotaSupported(const std::string& uuid) {
81     return !FindQuotaDeviceForUuid(uuid).empty();
82 }
83 
GetOccupiedSpaceForUid(const std::string & uuid,uid_t uid)84 int64_t GetOccupiedSpaceForUid(const std::string& uuid, uid_t uid) {
85     const std::string device = FindQuotaDeviceForUuid(uuid);
86     if (device == "") {
87         return -1;
88     }
89     struct dqblk dq;
90     if (quotactl(QCMD(Q_GETQUOTA, USRQUOTA), device.c_str(), uid,
91             reinterpret_cast<char*>(&dq)) != 0) {
92         if (errno != ESRCH) {
93             PLOG(ERROR) << "Failed to quotactl " << device << " for UID " << uid;
94         }
95         return -1;
96     } else {
97 #if MEASURE_DEBUG
98         LOG(DEBUG) << "quotactl() for UID " << uid << " " << dq.dqb_curspace;
99 #endif
100         return dq.dqb_curspace;
101     }
102 }
103 
GetOccupiedSpaceForProjectId(const std::string & uuid,int projectId)104 int64_t GetOccupiedSpaceForProjectId(const std::string& uuid, int projectId) {
105     const std::string device = FindQuotaDeviceForUuid(uuid);
106     if (device == "") {
107         return -1;
108     }
109     struct dqblk dq;
110     if (quotactl(QCMD(Q_GETQUOTA, PRJQUOTA), device.c_str(), projectId,
111             reinterpret_cast<char*>(&dq)) != 0) {
112         if (errno != ESRCH) {
113             PLOG(ERROR) << "Failed to quotactl " << device << " for Project ID " << projectId;
114         }
115         return -1;
116     } else {
117 #if MEASURE_DEBUG
118         LOG(DEBUG) << "quotactl() for Project ID " << projectId << " " << dq.dqb_curspace;
119 #endif
120         return dq.dqb_curspace;
121     }
122 }
123 
GetOccupiedSpaceForGid(const std::string & uuid,gid_t gid)124 int64_t GetOccupiedSpaceForGid(const std::string& uuid, gid_t gid) {
125     const std::string device = FindQuotaDeviceForUuid(uuid);
126     if (device == "") {
127         return -1;
128     }
129     struct dqblk dq;
130     if (quotactl(QCMD(Q_GETQUOTA, GRPQUOTA), device.c_str(), gid,
131             reinterpret_cast<char*>(&dq)) != 0) {
132         if (errno != ESRCH) {
133             PLOG(ERROR) << "Failed to quotactl " << device << " for GID " << gid;
134         }
135         return -1;
136     } else {
137 #if MEASURE_DEBUG
138         LOG(DEBUG) << "quotactl() for GID " << gid << " " << dq.dqb_curspace;
139 #endif
140         return dq.dqb_curspace;
141     }
142 
143 }
144 
145 }  // namespace installd
146 }  // namespace android
147