csharrison | 7d26a14 | 2016-08-20 06:43:44 +0900 | [diff] [blame] | 1 | // Copyright 2016 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef BASE_TEST_FUZZED_DATA_PROVIDER_H_ |
| 6 | #define BASE_TEST_FUZZED_DATA_PROVIDER_H_ |
| 7 | |
| 8 | #include <stdint.h> |
| 9 | |
csharrison | 5bc46b8 | 2016-10-20 07:37:08 +0900 | [diff] [blame] | 10 | #include <string> |
| 11 | |
csharrison | 7d26a14 | 2016-08-20 06:43:44 +0900 | [diff] [blame] | 12 | #include "base/base_export.h" |
| 13 | #include "base/macros.h" |
| 14 | #include "base/strings/string_piece.h" |
| 15 | |
| 16 | namespace base { |
| 17 | |
| 18 | // Utility class to break up fuzzer input for multiple consumers. Whenever run |
| 19 | // on the same input, provides the same output, as long as its methods are |
| 20 | // called in the same order, with the same arguments. |
| 21 | class FuzzedDataProvider { |
| 22 | public: |
| 23 | // |data| is an array of length |size| that the FuzzedDataProvider wraps to |
| 24 | // provide more granular access. |data| must outlive the FuzzedDataProvider. |
| 25 | FuzzedDataProvider(const uint8_t* data, size_t size); |
| 26 | ~FuzzedDataProvider(); |
| 27 | |
csharrison | 5bc46b8 | 2016-10-20 07:37:08 +0900 | [diff] [blame] | 28 | // Returns a std::string containing |num_bytes| of input data. If fewer than |
| 29 | // |num_bytes| of data remain, returns a shorter std::string containing all |
| 30 | // of the data that's left. |
| 31 | std::string ConsumeBytes(size_t num_bytes); |
csharrison | 7d26a14 | 2016-08-20 06:43:44 +0900 | [diff] [blame] | 32 | |
csharrison | 5bc46b8 | 2016-10-20 07:37:08 +0900 | [diff] [blame] | 33 | // Returns a std::string containing all remaining bytes of the input data. |
| 34 | std::string ConsumeRemainingBytes(); |
csharrison | 7d26a14 | 2016-08-20 06:43:44 +0900 | [diff] [blame] | 35 | |
mmenke | 44755fb | 2016-11-22 06:12:31 +0900 | [diff] [blame] | 36 | // Returns a std::string of length from 0 to |max_length|. When it runs out of |
| 37 | // input data, returns what remains of the input. Designed to be more stable |
| 38 | // with respect to a fuzzer inserting characters than just picking a random |
| 39 | // length and then consuming that many bytes with ConsumeBytes(). |
| 40 | std::string ConsumeRandomLengthString(size_t max_length); |
| 41 | |
csharrison | 7d26a14 | 2016-08-20 06:43:44 +0900 | [diff] [blame] | 42 | // Returns a number in the range [min, max] by consuming bytes from the input |
| 43 | // data. The value might not be uniformly distributed in the given range. If |
| 44 | // there's no input data left, always returns |min|. |min| must be less than |
| 45 | // or equal to |max|. |
| 46 | uint32_t ConsumeUint32InRange(uint32_t min, uint32_t max); |
| 47 | int ConsumeInt32InRange(int min, int max); |
| 48 | |
| 49 | // Returns a bool, or false when no data remains. |
| 50 | bool ConsumeBool(); |
| 51 | |
| 52 | // Returns a uint8_t from the input or 0 if nothing remains. This is |
| 53 | // equivalent to ConsumeUint32InRange(0, 0xFF). |
| 54 | uint8_t ConsumeUint8(); |
| 55 | |
| 56 | // Returns a uint16_t from the input. If fewer than 2 bytes of data remain |
| 57 | // will fill the most significant bytes with 0. This is equivalent to |
| 58 | // ConsumeUint32InRange(0, 0xFFFF). |
| 59 | uint16_t ConsumeUint16(); |
| 60 | |
| 61 | // Returns a value from |array|, consuming as many bytes as needed to do so. |
| 62 | // |array| must be a fixed-size array. Equivalent to |
| 63 | // array[ConsumeUint32InRange(sizeof(array)-1)]; |
| 64 | template <typename Type, size_t size> |
| 65 | Type PickValueInArray(Type (&array)[size]) { |
| 66 | return array[ConsumeUint32InRange(0, size - 1)]; |
| 67 | } |
| 68 | |
| 69 | // Reports the remaining bytes available for fuzzed input. |
| 70 | size_t remaining_bytes() { return remaining_data_.length(); } |
| 71 | |
| 72 | private: |
| 73 | StringPiece remaining_data_; |
| 74 | |
| 75 | DISALLOW_COPY_AND_ASSIGN(FuzzedDataProvider); |
| 76 | }; |
| 77 | |
| 78 | } // namespace base |
| 79 | |
| 80 | #endif // BASE_TEST_FUZZED_DATA_PROVIDER_H_ |