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 #pragma once
17 
18 #include "frameworks/base/cmds/statsd/src/statsd_config.pb.h"
19 
20 namespace android {
21 namespace os {
22 namespace statsd {
23 
24 class HashableDimensionKey;
25 struct Matcher;
26 struct Field;
27 struct FieldValue;
28 
29 const int32_t kAttributionField = 1;
30 const int32_t kMaxLogDepth = 2;
31 const int32_t kLastBitMask = 0x80;
32 const int32_t kClearLastBitDeco = 0x7f;
33 const int32_t kClearAllPositionMatcherMask = 0xffff00ff;
34 
35 enum Type { UNKNOWN, INT, LONG, FLOAT, DOUBLE, STRING, STORAGE };
36 
37 int32_t getEncodedField(int32_t pos[], int32_t depth, bool includeDepth);
38 
39 int32_t encodeMatcherMask(int32_t mask[], int32_t depth);
40 
41 // Get the encoded field for a leaf with a [field] number at depth 0;
getSimpleField(size_t field)42 inline int32_t getSimpleField(size_t field) {
43     return ((int32_t)field << 8 * 2);
44 }
45 
46 /**
47  * Field is a wrapper class for 2 integers that represents the field of a log element in its Atom
48  * proto.
49  * [mTag]: the atom id.
50  * [mField]: encoded path from the root (atom) to leaf.
51  *
52  * For example:
53  * WakeLockStateChanged {
54  *    repeated AttributionNode = 1;
55  *    int state = 2;
56  *    string tag = 3;
57  * }
58  * Read from logd, the items are structured as below:
59  * [[[1000, "tag"], [2000, "tag2"],], 2,"hello"]
60  *
61  * When we read through the list, we will encode each field in a 32bit integer.
62  * 8bit segments   |--------|--------|--------|--------|
63  *                    Depth   field0 [L]field1 [L]field1
64  *
65  *  The first 8 bits are the depth of the field. for example, the uid 1000 has depth 2.
66  *  The following 3 8-bit are for the item's position at each level.
67  *  The first bit of each 8bits field is reserved to mark if the item is the last item at that level
68  *  this is to make matching easier later.
69  *
70  *  The above wakelock event is translated into FieldValue pairs.
71  *  0x02010101->1000
72  *  0x02010182->tag
73  *  0x02018201->2000
74  *  0x02018282->tag2
75  *  0x00020000->2
76  *  0x00030000->"hello"
77  *
78  *  This encoding is the building block for the later operations.
79  *  Please see the definition for Matcher below to see how the matching is done.
80  */
81 struct Field {
82 private:
83     int32_t mTag;
84     int32_t mField;
85 
86 public:
FieldField87     Field() {}
88 
FieldField89     Field(int32_t tag, int32_t pos[], int32_t depth) : mTag(tag) {
90         mField = getEncodedField(pos, depth, true);
91     }
92 
FieldField93     Field(const Field& from) : mTag(from.getTag()), mField(from.getField()) {
94     }
95 
FieldField96     Field(int32_t tag, int32_t field) : mTag(tag), mField(field){};
97 
setFieldField98     inline void setField(int32_t field) {
99         mField = field;
100     }
101 
setTagField102     inline void setTag(int32_t tag) {
103         mTag = tag;
104     }
105 
decorateLastPosField106     inline void decorateLastPos(int32_t depth) {
107         int32_t mask = kLastBitMask << 8 * (kMaxLogDepth - depth);
108         mField |= mask;
109     }
110 
getTagField111     inline int32_t getTag() const {
112         return mTag;
113     }
114 
getDepthField115     inline int32_t getDepth() const {
116         return (mField >> 24);
117     }
118 
getPathField119     inline int32_t getPath(int32_t depth) const {
120         if (depth > 2 || depth < 0) return 0;
121 
122         int32_t field = (mField & 0x00ffffff);
123         int32_t mask = 0xffffffff;
124         return (field & (mask << 8 * (kMaxLogDepth - depth)));
125     }
126 
getPrefixField127     inline int32_t getPrefix(int32_t depth) const {
128         if (depth == 0) return 0;
129         return getPath(depth - 1);
130     }
131 
getFieldField132     inline int32_t getField() const {
133         return mField;
134     }
135 
getRawPosAtDepthField136     inline int32_t getRawPosAtDepth(int32_t depth) const {
137         int32_t field = (mField & 0x00ffffff);
138         int32_t shift = 8 * (kMaxLogDepth - depth);
139         int32_t mask = 0xff << shift;
140 
141         return (field & mask) >> shift;
142     }
143 
getPosAtDepthField144     inline int32_t getPosAtDepth(int32_t depth) const {
145         return getRawPosAtDepth(depth) & kClearLastBitDeco;
146     }
147 
148     // Check if the first bit of the 8-bit segment for depth is 1
isLastPosField149     inline bool isLastPos(int32_t depth) const {
150         int32_t field = (mField & 0x00ffffff);
151         int32_t mask = kLastBitMask << 8 * (kMaxLogDepth - depth);
152         return (field & mask) != 0;
153     }
154 
155     // if the 8-bit segment is all 0's
isAnyPosMatcherField156     inline bool isAnyPosMatcher(int32_t depth) const {
157         return getDepth() >= depth && getRawPosAtDepth(depth) == 0;
158     }
159     // if the 8bit is 0x80 (1000 0000)
isLastPosMatcherField160     inline bool isLastPosMatcher(int32_t depth) const {
161         return getDepth() >= depth && getRawPosAtDepth(depth) == kLastBitMask;
162     }
163 
164     inline bool operator==(const Field& that) const {
165         return mTag == that.getTag() && mField == that.getField();
166     };
167 
168     inline bool operator!=(const Field& that) const {
169         return mTag != that.getTag() || mField != that.getField();
170     };
171 
172     bool operator<(const Field& that) const {
173         if (mTag != that.getTag()) {
174             return mTag < that.getTag();
175         }
176 
177         if (mField != that.getField()) {
178             return mField < that.getField();
179         }
180 
181         return false;
182     }
183     bool matches(const Matcher& that) const;
184 };
185 
186 /**
187  * Matcher represents a leaf matcher in the FieldMatcher in statsd_config.
188  *
189  * It contains all information needed to match one or more leaf node.
190  * All information is encoded in a Field(2 ints) and a bit mask(1 int).
191  *
192  * For example, to match the first/any/last uid field in attribution chain in Atom 10,
193  * we have the following FieldMatcher in statsd_config
194  *    FieldMatcher {
195  *        field:10
196  *         FieldMatcher {
197  *              field:1
198  *              position: any/last/first
199  *              FieldMatcher {
200  *                  field:1
201  *              }
202  *          }
203  *     }
204  *
205  * We translate the FieldMatcher into a Field, and mask
206  * First: [Matcher Field] 0x02010101  [Mask]0xff7f7f7f
207  * Last:  [Matcher Field] 0x02018001  [Mask]0xff7f807f
208  * Any:   [Matcher Field] 0x02010001  [Mask]0xff7f007f
209  * All:   [Matcher Field] 0x02010001  [Mask]0xff7f7f7f
210  *
211  * [To match a log Field with a Matcher] we apply the bit mask to the log Field and check if
212  * the result is equal to the Matcher Field. That's a bit wise AND operation + check if 2 ints are
213  * equal. Nothing can beat the performance of this matching algorithm.
214  *
215  * TODO(b/110561213): ADD EXAMPLE HERE.
216  */
217 struct Matcher {
MatcherMatcher218     Matcher(const Field& matcher, int32_t mask) : mMatcher(matcher), mMask(mask){};
219 
220     const Field mMatcher;
221     const int32_t mMask;
222 
getMatcherMatcher223     inline const Field& getMatcher() const {
224         return mMatcher;
225     }
226 
getMaskMatcher227     inline int32_t getMask() const {
228         return mMask;
229     }
230 
getRawMaskAtDepthMatcher231     inline int32_t getRawMaskAtDepth(int32_t depth) const {
232         int32_t field = (mMask & 0x00ffffff);
233         int32_t shift = 8 * (kMaxLogDepth - depth);
234         int32_t mask = 0xff << shift;
235 
236         return (field & mask) >> shift;
237     }
238 
hasAllPositionMatcherMatcher239     bool hasAllPositionMatcher() const {
240         return mMatcher.getDepth() == 2 && getRawMaskAtDepth(1) == 0x7f;
241     }
242 
hasAnyPositionMatcherMatcher243     bool hasAnyPositionMatcher(int* prefix) const {
244         if (mMatcher.getDepth() == 2 && mMatcher.getRawPosAtDepth(1) == 0) {
245             (*prefix) = mMatcher.getPrefix(1);
246             return true;
247         }
248         return false;
249     }
250 
251     inline bool operator!=(const Matcher& that) const {
252         return mMatcher != that.getMatcher() || mMask != that.getMask();
253     }
254 
255     inline bool operator==(const Matcher& that) const {
256         return mMatcher == that.mMatcher && mMask == that.mMask;
257     }
258 };
259 
getSimpleMatcher(int32_t tag,size_t field)260 inline Matcher getSimpleMatcher(int32_t tag, size_t field) {
261     return Matcher(Field(tag, getSimpleField(field)), 0xff7f0000);
262 }
263 
264 /**
265  * A wrapper for a union type to contain multiple types of values.
266  *
267  */
268 struct Value {
ValueValue269     Value() : type(UNKNOWN) {}
270 
ValueValue271     Value(int32_t v) {
272         int_value = v;
273         type = INT;
274     }
275 
ValueValue276     Value(int64_t v) {
277         long_value = v;
278         type = LONG;
279     }
280 
ValueValue281     Value(float v) {
282         float_value = v;
283         type = FLOAT;
284     }
285 
ValueValue286     Value(double v) {
287         double_value = v;
288         type = DOUBLE;
289     }
290 
ValueValue291     Value(const std::string& v) {
292         str_value = v;
293         type = STRING;
294     }
295 
ValueValue296     Value(const std::vector<uint8_t>& v) {
297         storage_value = v;
298         type = STORAGE;
299     }
300 
setIntValue301     void setInt(int32_t v) {
302         int_value = v;
303         type = INT;
304     }
305 
setLongValue306     void setLong(int64_t v) {
307         long_value = v;
308         type = LONG;
309     }
310 
setFloatValue311     void setFloat(float v) {
312         float_value = v;
313         type = FLOAT;
314     }
315 
setDoubleValue316     void setDouble(double v) {
317         double_value = v;
318         type = DOUBLE;
319     }
320 
321     union {
322         int32_t int_value;
323         int64_t long_value;
324         float float_value;
325         double double_value;
326     };
327     std::string str_value;
328     std::vector<uint8_t> storage_value;
329 
330     Type type;
331 
332     std::string toString() const;
333 
334     bool isZero() const;
335 
getTypeValue336     Type getType() const {
337         return type;
338     }
339 
340     double getDouble() const;
341 
342     Value(const Value& from);
343 
344     bool operator==(const Value& that) const;
345     bool operator!=(const Value& that) const;
346 
347     bool operator<(const Value& that) const;
348     bool operator>(const Value& that) const;
349     bool operator>=(const Value& that) const;
350     Value operator-(const Value& that) const;
351     Value& operator+=(const Value& that);
352     Value& operator=(const Value& that);
353 };
354 
355 /**
356  * Represents a log item, or a dimension item (They are essentially the same).
357  */
358 struct FieldValue {
FieldValueFieldValue359     FieldValue() {}
FieldValueFieldValue360     FieldValue(const Field& field, const Value& value) : mField(field), mValue(value) {
361     }
362     bool operator==(const FieldValue& that) const {
363         return mField == that.mField && mValue == that.mValue;
364     }
365     bool operator!=(const FieldValue& that) const {
366         return mField != that.mField || mValue != that.mValue;
367     }
368     bool operator<(const FieldValue& that) const {
369         if (mField != that.mField) {
370             return mField < that.mField;
371         }
372 
373         if (mValue != that.mValue) {
374             return mValue < that.mValue;
375         }
376 
377         return false;
378     }
379 
380     Field mField;
381     Value mValue;
382 };
383 
384 bool HasPositionANY(const FieldMatcher& matcher);
385 bool HasPositionALL(const FieldMatcher& matcher);
386 
387 bool isAttributionUidField(const FieldValue& value);
388 
389 /* returns uid if the field is uid field, or -1 if the field is not a uid field */
390 int getUidIfExists(const FieldValue& value);
391 
392 void translateFieldMatcher(const FieldMatcher& matcher, std::vector<Matcher>* output);
393 
394 bool isAttributionUidField(const Field& field, const Value& value);
395 
396 bool equalDimensions(const std::vector<Matcher>& dimension_a,
397                      const std::vector<Matcher>& dimension_b);
398 }  // namespace statsd
399 }  // namespace os
400 }  // namespace android
401