1 /*
2 * Copyright (C) 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 "UidRanges.h"
18
19 #include "NetdConstants.h"
20
21 #include <inttypes.h>
22 #include <limits.h>
23 #include <stdlib.h>
24
25 #include <android-base/stringprintf.h>
26 #include <log/log.h>
27
28 using android::base::StringAppendF;
29
30 namespace android {
31 namespace net {
32
hasUid(uid_t uid) const33 bool UidRanges::hasUid(uid_t uid) const {
34 if (uid > (unsigned) INT32_MAX) {
35 ALOGW("UID larger than 32 bits: %" PRIu64, static_cast<uint64_t>(uid));
36 return false;
37 }
38 const int32_t intUid = static_cast<int32_t>(uid);
39
40 auto iter = std::lower_bound(mRanges.begin(), mRanges.end(), UidRange(intUid, intUid));
41 return (iter != mRanges.end() && iter->getStart() == intUid) ||
42 (iter != mRanges.begin() && (--iter)->getStop() >= intUid);
43 }
44
getRanges() const45 const std::vector<UidRange>& UidRanges::getRanges() const {
46 return mRanges;
47 }
48
parseFrom(int argc,char * argv[])49 bool UidRanges::parseFrom(int argc, char* argv[]) {
50 mRanges.clear();
51 for (int i = 0; i < argc; ++i) {
52 if (!*argv[i]) {
53 // The UID string is empty.
54 return false;
55 }
56 char* endPtr;
57 uid_t uidStart = strtoul(argv[i], &endPtr, 0);
58 uid_t uidEnd;
59 if (!*endPtr) {
60 // Found a single UID. The range contains just the one UID.
61 uidEnd = uidStart;
62 } else if (*endPtr == '-') {
63 if (!*++endPtr) {
64 // Unexpected end of string.
65 return false;
66 }
67 uidEnd = strtoul(endPtr, &endPtr, 0);
68 if (*endPtr) {
69 // Illegal trailing chars.
70 return false;
71 }
72 if (uidEnd < uidStart) {
73 // Invalid order.
74 return false;
75 }
76 } else {
77 // Not a single uid, not a range. Found some other illegal char.
78 return false;
79 }
80 if (uidStart == INVALID_UID || uidEnd == INVALID_UID) {
81 // Invalid UIDs.
82 return false;
83 }
84 mRanges.push_back(UidRange(uidStart, uidEnd));
85 }
86 std::sort(mRanges.begin(), mRanges.end());
87 return true;
88 }
89
UidRanges(const std::vector<UidRange> & ranges)90 UidRanges::UidRanges(const std::vector<UidRange>& ranges) {
91 mRanges = ranges;
92 std::sort(mRanges.begin(), mRanges.end());
93 }
94
add(const UidRanges & other)95 void UidRanges::add(const UidRanges& other) {
96 auto middle = mRanges.insert(mRanges.end(), other.mRanges.begin(), other.mRanges.end());
97 std::inplace_merge(mRanges.begin(), middle, mRanges.end());
98 }
99
remove(const UidRanges & other)100 void UidRanges::remove(const UidRanges& other) {
101 auto end = std::set_difference(mRanges.begin(), mRanges.end(), other.mRanges.begin(),
102 other.mRanges.end(), mRanges.begin());
103 mRanges.erase(end, mRanges.end());
104 }
105
toString() const106 std::string UidRanges::toString() const {
107 std::string s("UidRanges{ ");
108 for (const auto &range : mRanges) {
109 if (range.length() == 0) {
110 StringAppendF(&s, "<BAD: %u-%u> ", range.getStart(), range.getStop());
111 } else if (range.length() == 1) {
112 StringAppendF(&s, "%u ", range.getStart());
113 } else {
114 StringAppendF(&s, "%u-%u ", range.getStart(), range.getStop());
115 }
116 }
117 StringAppendF(&s, "}");
118 return s;
119 }
120
121 } // namespace net
122 } // namespace android
123