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/*
* Copyright 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <functional>
#include <iostream>
#include <memory>
#include "FuzzFormatTypes.h"
#include "fuzzer/FuzzedDataProvider.h"
#include "utils/String8.h"
static constexpr int MAX_STRING_BYTES = 256;
static constexpr uint8_t MAX_OPERATIONS = 50;
// Interestingly, 2147483614 (INT32_MAX - 33) seems to be the max value that is handled for format
// flags. Unfortunately we need to use a smaller value so we avoid consuming too much memory.
void fuzzFormat(FuzzedDataProvider* dataProvider, android::String8* str1, bool shouldAppend);
std::vector<std::function<void(FuzzedDataProvider*, android::String8*, android::String8*)>>
operations = {
// Bytes and size
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->bytes();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->isEmpty();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->length();
},
// Casing
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->toLower();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8* str2) -> void {
str1->removeAll(str2->c_str());
},
[](FuzzedDataProvider*, android::String8* str1, android::String8* str2) -> void {
const android::String8& constRef(*str2);
str1->compare(constRef);
},
// Append and format
[](FuzzedDataProvider*, android::String8* str1, android::String8* str2) -> void {
str1->append(str2->c_str());
},
[](FuzzedDataProvider* dataProvider, android::String8* str1, android::String8*)
-> void { fuzzFormat(dataProvider, str1, dataProvider->ConsumeBool()); },
// Find operation
[](FuzzedDataProvider* dataProvider, android::String8* str1,
android::String8* str2) -> void {
// We need to get a value from our fuzzer here.
int start_index = dataProvider->ConsumeIntegralInRange<int>(0, str1->size());
str1->find(str2->c_str(), start_index);
},
// Path handling
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->getBasePath();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->getPathExtension();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->getPathLeaf();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->getPathDir();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
str1->convertToResPath();
},
[](FuzzedDataProvider*, android::String8* str1, android::String8*) -> void {
std::shared_ptr<android::String8> path_out_str =
std::make_shared<android::String8>();
str1->walkPath(path_out_str.get());
path_out_str->clear();
},
[](FuzzedDataProvider* dataProvider, android::String8* str1,
android::String8*) -> void {
str1->appendPath(dataProvider->ConsumeBytesWithTerminator<char>(5).data());
},
};
void fuzzFormat(FuzzedDataProvider* dataProvider, android::String8* str1, bool shouldAppend) {
FormatChar formatType = dataProvider->ConsumeEnum<FormatChar>();
std::string formatString("%");
// Width specifier
if (dataProvider->ConsumeBool()) {
// Left pad with zeroes
if (dataProvider->ConsumeBool()) {
formatString.push_back('0');
}
// Right justify (or left justify if negative)
int32_t justify = dataProvider->ConsumeIntegralInRange<int32_t>(-kMaxFormatFlagValue,
kMaxFormatFlagValue);
formatString += std::to_string(justify);
}
// The # specifier only works with o, x, X, a, A, e, E, f, F, g, and G
if (canApplyFlag(formatType, '#') && dataProvider->ConsumeBool()) {
formatString.push_back('#');
}
// Precision specifier
if (canApplyFlag(formatType, '.') && dataProvider->ConsumeBool()) {
formatString.push_back('.');
formatString +=
std::to_string(dataProvider->ConsumeIntegralInRange<int>(0, kMaxFormatFlagValue));
}
formatString.push_back(kFormatChars.at(static_cast<uint8_t>(formatType)));
switch (formatType) {
case SIGNED_DECIMAL: {
int val = dataProvider->ConsumeIntegral<int>();
if (shouldAppend) {
str1->appendFormat(formatString.c_str(), val);
} else {
str1->format(formatString.c_str(), dataProvider->ConsumeIntegral<int>());
}
break;
}
case UNSIGNED_DECIMAL:
case UNSIGNED_OCTAL:
case UNSIGNED_HEX_LOWER:
case UNSIGNED_HEX_UPPER: {
// Unsigned integers for u, o, x, and X
uint val = dataProvider->ConsumeIntegral<uint>();
if (shouldAppend) {
str1->appendFormat(formatString.c_str(), val);
} else {
str1->format(formatString.c_str(), val);
}
break;
}
case FLOAT_LOWER:
case FLOAT_UPPER:
case EXPONENT_LOWER:
case EXPONENT_UPPER:
case SHORT_EXP_LOWER:
case SHORT_EXP_UPPER:
case HEX_FLOAT_LOWER:
case HEX_FLOAT_UPPER: {
// Floating points for f, F, e, E, g, G, a, and A
float val = dataProvider->ConsumeFloatingPoint<float>();
if (shouldAppend) {
str1->appendFormat(formatString.c_str(), val);
} else {
str1->format(formatString.c_str(), val);
}
break;
}
case CHAR: {
char val = dataProvider->ConsumeIntegral<char>();
if (shouldAppend) {
str1->appendFormat(formatString.c_str(), val);
} else {
str1->format(formatString.c_str(), val);
}
break;
}
case STRING: {
std::string val = dataProvider->ConsumeRandomLengthString(MAX_STRING_BYTES);
if (shouldAppend) {
str1->appendFormat(formatString.c_str(), val.c_str());
} else {
str1->format(formatString.c_str(), val.c_str());
}
break;
}
case POINTER: {
uintptr_t val = dataProvider->ConsumeIntegral<uintptr_t>();
if (shouldAppend) {
str1->appendFormat(formatString.c_str(), val);
} else {
str1->format(formatString.c_str(), val);
}
break;
}
}
}
void callFunc(uint8_t index, FuzzedDataProvider* dataProvider, android::String8* str1,
android::String8* str2) {
operations[index](dataProvider, str1, str2);
}
extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
FuzzedDataProvider dataProvider(data, size);
// Generate vector lengths
const size_t kVecOneLen = dataProvider.ConsumeIntegralInRange<size_t>(1, MAX_STRING_BYTES);
const size_t kVecTwoLen = dataProvider.ConsumeIntegralInRange<size_t>(1, MAX_STRING_BYTES);
// Populate vectors
std::vector<char> vec = dataProvider.ConsumeBytesWithTerminator<char>(kVecOneLen);
std::vector<char> vec_two = dataProvider.ConsumeBytesWithTerminator<char>(kVecTwoLen);
// Create UTF-8 pointers
android::String8 str_one_utf8 = android::String8(vec.data());
android::String8 str_two_utf8 = android::String8(vec_two.data());
// Run operations against strings
int opsRun = 0;
while (dataProvider.remaining_bytes() > 0 && opsRun++ < MAX_OPERATIONS) {
uint8_t op = dataProvider.ConsumeIntegralInRange<uint8_t>(0, operations.size() - 1);
operations[op](&dataProvider, &str_one_utf8, &str_two_utf8);
}
// Just to be extra sure these can be freed, we're going to explicitly clear
// them
str_one_utf8.clear();
str_two_utf8.clear();
return 0;
}
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