1 //===- llvm/unittest/Support/DataExtractorTest.cpp - DataExtractor tests --===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/Support/DataExtractor.h"
10 #include "llvm/Testing/Support/Error.h"
11 #include "gtest/gtest.h"
12 using namespace llvm;
13 
14 namespace {
15 
16 const char numberData[] = "\x80\x90\xFF\xFF\x80\x00\x00\x00";
17 const char leb128data[] = "\xA6\x49";
18 const char bigleb128data[] = "\xAA\xA9\xFF\xAA\xFF\xAA\xFF\x4A";
19 
TEST(DataExtractorTest,OffsetOverflow)20 TEST(DataExtractorTest, OffsetOverflow) {
21   DataExtractor DE(StringRef(numberData, sizeof(numberData)-1), false, 8);
22   EXPECT_FALSE(DE.isValidOffsetForDataOfSize(-2U, 5));
23 }
24 
TEST(DataExtractorTest,UnsignedNumbers)25 TEST(DataExtractorTest, UnsignedNumbers) {
26   DataExtractor DE(StringRef(numberData, sizeof(numberData)-1), false, 8);
27   uint64_t offset = 0;
28 
29   EXPECT_EQ(0x80U, DE.getU8(&offset));
30   EXPECT_EQ(1U, offset);
31   offset = 0;
32   EXPECT_EQ(0x8090U, DE.getU16(&offset));
33   EXPECT_EQ(2U, offset);
34   offset = 0;
35   EXPECT_EQ(0x8090FFFFU, DE.getU32(&offset));
36   EXPECT_EQ(4U, offset);
37   offset = 0;
38   EXPECT_EQ(0x8090FFFF80000000ULL, DE.getU64(&offset));
39   EXPECT_EQ(8U, offset);
40   offset = 0;
41   EXPECT_EQ(0x8090FFFF80000000ULL, DE.getAddress(&offset));
42   EXPECT_EQ(8U, offset);
43   offset = 0;
44 
45   uint32_t data[2];
46   EXPECT_EQ(data, DE.getU32(&offset, data, 2));
47   EXPECT_EQ(0x8090FFFFU, data[0]);
48   EXPECT_EQ(0x80000000U, data[1]);
49   EXPECT_EQ(8U, offset);
50   offset = 0;
51 
52   // Now for little endian.
53   DE = DataExtractor(StringRef(numberData, sizeof(numberData)-1), true, 4);
54   EXPECT_EQ(0x9080U, DE.getU16(&offset));
55   EXPECT_EQ(2U, offset);
56   offset = 0;
57   EXPECT_EQ(0xFFFF9080U, DE.getU32(&offset));
58   EXPECT_EQ(4U, offset);
59   offset = 0;
60   EXPECT_EQ(0x80FFFF9080ULL, DE.getU64(&offset));
61   EXPECT_EQ(8U, offset);
62   offset = 0;
63   EXPECT_EQ(0xFFFF9080U, DE.getAddress(&offset));
64   EXPECT_EQ(4U, offset);
65   offset = 0;
66 
67   EXPECT_EQ(data, DE.getU32(&offset, data, 2));
68   EXPECT_EQ(0xFFFF9080U, data[0]);
69   EXPECT_EQ(0x80U, data[1]);
70   EXPECT_EQ(8U, offset);
71 }
72 
TEST(DataExtractorTest,SignedNumbers)73 TEST(DataExtractorTest, SignedNumbers) {
74   DataExtractor DE(StringRef(numberData, sizeof(numberData)-1), false, 8);
75   uint64_t offset = 0;
76 
77   EXPECT_EQ(-128, DE.getSigned(&offset, 1));
78   EXPECT_EQ(1U, offset);
79   offset = 0;
80   EXPECT_EQ(-32624, DE.getSigned(&offset, 2));
81   EXPECT_EQ(2U, offset);
82   offset = 0;
83   EXPECT_EQ(-2137980929, DE.getSigned(&offset, 4));
84   EXPECT_EQ(4U, offset);
85   offset = 0;
86   EXPECT_EQ(-9182558167379214336LL, DE.getSigned(&offset, 8));
87   EXPECT_EQ(8U, offset);
88 }
89 
TEST(DataExtractorTest,Strings)90 TEST(DataExtractorTest, Strings) {
91   const char stringData[] = "hellohello\0hello";
92   DataExtractor DE(StringRef(stringData, sizeof(stringData)-1), false, 8);
93   uint64_t offset = 0;
94 
95   EXPECT_EQ(stringData, DE.getCStr(&offset));
96   EXPECT_EQ(11U, offset);
97   EXPECT_EQ(nullptr, DE.getCStr(&offset));
98   EXPECT_EQ(11U, offset);
99 
100   DataExtractor::Cursor C(0);
101   EXPECT_EQ(stringData, DE.getCStr(C));
102   EXPECT_EQ(11U, C.tell());
103   EXPECT_EQ(nullptr, DE.getCStr(C));
104   EXPECT_EQ(11U, C.tell());
105   EXPECT_THAT_ERROR(
106       C.takeError(),
107       FailedWithMessage("no null terminated string at offset 0xb"));
108 }
109 
TEST(DataExtractorTest,LEB128)110 TEST(DataExtractorTest, LEB128) {
111   DataExtractor DE(StringRef(leb128data, sizeof(leb128data)-1), false, 8);
112   uint64_t offset = 0;
113 
114   EXPECT_EQ(9382ULL, DE.getULEB128(&offset));
115   EXPECT_EQ(2U, offset);
116   offset = 0;
117   EXPECT_EQ(-7002LL, DE.getSLEB128(&offset));
118   EXPECT_EQ(2U, offset);
119 
120   DataExtractor BDE(StringRef(bigleb128data, sizeof(bigleb128data)-1), false,8);
121   offset = 0;
122   EXPECT_EQ(42218325750568106ULL, BDE.getULEB128(&offset));
123   EXPECT_EQ(8U, offset);
124   offset = 0;
125   EXPECT_EQ(-29839268287359830LL, BDE.getSLEB128(&offset));
126   EXPECT_EQ(8U, offset);
127 }
128 
TEST(DataExtractorTest,LEB128_error)129 TEST(DataExtractorTest, LEB128_error) {
130   DataExtractor DE(StringRef("\x81"), false, 8);
131   uint64_t Offset = 0;
132   EXPECT_EQ(0U, DE.getULEB128(&Offset));
133   EXPECT_EQ(0U, Offset);
134 
135   Offset = 0;
136   EXPECT_EQ(0U, DE.getSLEB128(&Offset));
137   EXPECT_EQ(0U, Offset);
138 
139   DataExtractor::Cursor C(0);
140   EXPECT_EQ(0U, DE.getULEB128(C));
141   EXPECT_THAT_ERROR(
142       C.takeError(),
143       FailedWithMessage("unable to decode LEB128 at offset 0x00000000: "
144                         "malformed uleb128, extends past end"));
145 
146   C = DataExtractor::Cursor(0);
147   EXPECT_EQ(0U, DE.getSLEB128(C));
148   EXPECT_THAT_ERROR(
149       C.takeError(),
150       FailedWithMessage("unable to decode LEB128 at offset 0x00000000: "
151                         "malformed sleb128, extends past end"));
152 
153   // Show non-zero offsets are reported appropriately.
154   C = DataExtractor::Cursor(1);
155   EXPECT_EQ(0U, DE.getULEB128(C));
156   EXPECT_THAT_ERROR(
157       C.takeError(),
158       FailedWithMessage("unable to decode LEB128 at offset 0x00000001: "
159                         "malformed uleb128, extends past end"));
160 }
161 
TEST(DataExtractorTest,Cursor_tell)162 TEST(DataExtractorTest, Cursor_tell) {
163   DataExtractor DE(StringRef("AB"), false, 8);
164   DataExtractor::Cursor C(0);
165   // A successful read operation advances the cursor
166   EXPECT_EQ('A', DE.getU8(C));
167   EXPECT_EQ(1u, C.tell());
168 
169   // An unsuccessful one doesn't.
170   EXPECT_EQ(0u, DE.getU16(C));
171   EXPECT_EQ(1u, C.tell());
172 
173   // And neither do any subsequent operations.
174   EXPECT_EQ(0, DE.getU8(C));
175   EXPECT_EQ(1u, C.tell());
176 
177   consumeError(C.takeError());
178 }
179 
TEST(DataExtractorTest,Cursor_takeError)180 TEST(DataExtractorTest, Cursor_takeError) {
181   DataExtractor DE(StringRef("AB"), false, 8);
182   DataExtractor::Cursor C(0);
183   // Initially, the cursor is in the "success" state.
184   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
185 
186   // It remains "success" after a successful read.
187   EXPECT_EQ('A', DE.getU8(C));
188   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
189 
190   // An unsuccessful read sets the error state.
191   EXPECT_EQ(0u, DE.getU32(C));
192   EXPECT_THAT_ERROR(C.takeError(), Failed());
193 
194   // Once set the error sticks until explicitly cleared.
195   EXPECT_EQ(0u, DE.getU32(C));
196   EXPECT_EQ(0, DE.getU8(C));
197   EXPECT_THAT_ERROR(C.takeError(), Failed());
198 
199   // At which point reads can be succeed again.
200   EXPECT_EQ('B', DE.getU8(C));
201   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
202 }
203 
TEST(DataExtractorTest,Cursor_chaining)204 TEST(DataExtractorTest, Cursor_chaining) {
205   DataExtractor DE(StringRef("ABCD"), false, 8);
206   DataExtractor::Cursor C(0);
207 
208   // Multiple reads can be chained without trigerring any assertions.
209   EXPECT_EQ('A', DE.getU8(C));
210   EXPECT_EQ('B', DE.getU8(C));
211   EXPECT_EQ('C', DE.getU8(C));
212   EXPECT_EQ('D', DE.getU8(C));
213   // And the error checked at the end.
214   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
215 }
216 
217 #if defined(GTEST_HAS_DEATH_TEST) && defined(_DEBUG)
TEST(DataExtractorDeathTest,Cursor)218 TEST(DataExtractorDeathTest, Cursor) {
219   DataExtractor DE(StringRef("AB"), false, 8);
220 
221   // Even an unused cursor must be checked for errors:
222   EXPECT_DEATH(DataExtractor::Cursor(0),
223                "Success values must still be checked prior to being destroyed");
224 
225   {
226     auto C = std::make_unique<DataExtractor::Cursor>(0);
227     EXPECT_EQ(0u, DE.getU32(*C));
228     // It must also be checked after an unsuccessful operation.
229     // destruction.
230     EXPECT_DEATH(C.reset(), "unexpected end of data");
231     EXPECT_THAT_ERROR(C->takeError(), Failed());
232   }
233   {
234     auto C = std::make_unique<DataExtractor::Cursor>(0);
235     EXPECT_EQ('A', DE.getU8(*C));
236     // Same goes for a successful one.
237     EXPECT_DEATH(
238         C.reset(),
239         "Success values must still be checked prior to being destroyed");
240     EXPECT_THAT_ERROR(C->takeError(), Succeeded());
241   }
242   {
243     auto C = std::make_unique<DataExtractor::Cursor>(0);
244     EXPECT_EQ('A', DE.getU8(*C));
245     EXPECT_EQ(0u, DE.getU32(*C));
246     // Even if a successful operation is followed by an unsuccessful one.
247     EXPECT_DEATH(C.reset(), "unexpected end of data");
248     EXPECT_THAT_ERROR(C->takeError(), Failed());
249   }
250   {
251     auto C = std::make_unique<DataExtractor::Cursor>(0);
252     EXPECT_EQ(0u, DE.getU32(*C));
253     EXPECT_EQ(0, DE.getU8(*C));
254     // Even if an unsuccessful operation is followed by one that would normally
255     // succeed.
256     EXPECT_DEATH(C.reset(), "unexpected end of data");
257     EXPECT_THAT_ERROR(C->takeError(), Failed());
258   }
259 }
260 #endif
261 
TEST(DataExtractorTest,getU8_vector)262 TEST(DataExtractorTest, getU8_vector) {
263   DataExtractor DE(StringRef("AB"), false, 8);
264   DataExtractor::Cursor C(0);
265   SmallVector<uint8_t, 2> S;
266 
267   DE.getU8(C, S, 4);
268   EXPECT_THAT_ERROR(C.takeError(), Failed());
269   EXPECT_EQ("", toStringRef(S));
270 
271   DE.getU8(C, S, 2);
272   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
273   EXPECT_EQ("AB", toStringRef(S));
274 
275   C = DataExtractor::Cursor(0x47);
276   DE.getU8(C, S, 2);
277   EXPECT_THAT_ERROR(
278       C.takeError(),
279       FailedWithMessage("offset 0x47 is beyond the end of data at 0x2"));
280 }
281 
TEST(DataExtractorTest,getU24)282 TEST(DataExtractorTest, getU24) {
283   DataExtractor DE(StringRef("ABCD"), false, 8);
284   DataExtractor::Cursor C(0);
285 
286   EXPECT_EQ(0x414243u, DE.getU24(C));
287   EXPECT_EQ(0u, DE.getU24(C));
288   EXPECT_EQ(3u, C.tell());
289   EXPECT_THAT_ERROR(C.takeError(), Failed());
290 }
291 
TEST(DataExtractorTest,skip)292 TEST(DataExtractorTest, skip) {
293   DataExtractor DE(StringRef("AB"), false, 8);
294   DataExtractor::Cursor C(0);
295 
296   DE.skip(C, 4);
297   EXPECT_THAT_ERROR(C.takeError(), Failed());
298   EXPECT_EQ(0u, C.tell());
299 
300   DE.skip(C, 2);
301   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
302   EXPECT_EQ(2u, C.tell());
303 }
304 
TEST(DataExtractorTest,eof)305 TEST(DataExtractorTest, eof) {
306   DataExtractor DE(StringRef("A"), false, 8);
307   DataExtractor::Cursor C(0);
308 
309   EXPECT_FALSE(DE.eof(C));
310 
311   EXPECT_EQ(0, DE.getU16(C));
312   EXPECT_FALSE(DE.eof(C));
313   EXPECT_THAT_ERROR(C.takeError(), Failed());
314 
315   EXPECT_EQ('A', DE.getU8(C));
316   EXPECT_TRUE(DE.eof(C));
317   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
318 }
319 
TEST(DataExtractorTest,size)320 TEST(DataExtractorTest, size) {
321   uint8_t Data[] = {'A', 'B', 'C', 'D'};
322   DataExtractor DE1(StringRef(reinterpret_cast<char *>(Data), sizeof(Data)),
323                     false, 8);
324   EXPECT_EQ(DE1.size(), sizeof(Data));
325   DataExtractor DE2(ArrayRef<uint8_t>(Data), false, 8);
326   EXPECT_EQ(DE2.size(), sizeof(Data));
327 }
328 
TEST(DataExtractorTest,FixedLengthString)329 TEST(DataExtractorTest, FixedLengthString) {
330   const char Data[] = "hello\x00\x00\x00world  \thola\x00";
331   DataExtractor DE(StringRef(Data, sizeof(Data)-1), false, 8);
332   uint64_t Offset = 0;
333   StringRef Str;
334   // Test extracting too many bytes doesn't modify Offset and returns None.
335   Str = DE.getFixedLengthString(&Offset, sizeof(Data));
336   EXPECT_TRUE(Str.empty());
337   EXPECT_EQ(Offset, 0u);
338 
339   // Test extracting a fixed width C string with trailing NULL characters.
340   Str = DE.getFixedLengthString(&Offset, 8);
341   EXPECT_EQ(Offset, 8u);
342   EXPECT_EQ(Str.size(), 5u);
343   EXPECT_EQ(Str, "hello");
344   // Test extracting a fixed width C string with trailing space and tab
345   // characters.
346   Str = DE.getFixedLengthString(&Offset, 8, " \t");
347   EXPECT_EQ(Offset, 16u);
348   EXPECT_EQ(Str.size(), 5u);
349   EXPECT_EQ(Str, "world");
350   // Now extract a normal C string.
351   Str = DE.getCStrRef(&Offset);
352   EXPECT_EQ(Str.size(), 4u);
353   EXPECT_EQ(Str, "hola");
354 }
355 
356 
TEST(DataExtractorTest,GetBytes)357 TEST(DataExtractorTest, GetBytes) {
358   // Use data with an embedded NULL character for good measure.
359   const char Data[] = "\x01\x02\x00\x04";
360   StringRef Bytes(Data, sizeof(Data)-1);
361   DataExtractor DE(Bytes, false, 8);
362   uint64_t Offset = 0;
363   StringRef Str;
364   // Test extracting too many bytes doesn't modify Offset and returns None.
365   Str = DE.getBytes(&Offset, sizeof(Data));
366   EXPECT_TRUE(Str.empty());
367   EXPECT_EQ(Offset, 0u);
368   // Test extracting 4 bytes from the stream.
369   Str = DE.getBytes(&Offset, 4);
370   EXPECT_EQ(Offset, 4u);
371   EXPECT_EQ(Str.size(), 4u);
372   EXPECT_EQ(Str, Bytes);
373 
374   DataExtractor::Cursor C(0);
375   EXPECT_EQ(StringRef("\x01\x02"), DE.getBytes(C, 2));
376   EXPECT_EQ(StringRef("\x00\x04", 2), DE.getBytes(C, 2));
377   EXPECT_EQ(StringRef(), DE.getBytes(C, 2));
378   EXPECT_EQ(StringRef(), DE.getBytes(C, 2));
379   EXPECT_EQ(4u, C.tell());
380   EXPECT_THAT_ERROR(C.takeError(), Failed());
381 }
382 
383 }
384