1 //===- Minidump.cpp - Minidump object file implementation -----------------===//
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/Object/Minidump.h"
10 #include "llvm/Support/ConvertUTF.h"
11
12 using namespace llvm;
13 using namespace llvm::object;
14 using namespace llvm::minidump;
15
16 std::optional<ArrayRef<uint8_t>>
getRawStream(minidump::StreamType Type) const17 MinidumpFile::getRawStream(minidump::StreamType Type) const {
18 auto It = StreamMap.find(Type);
19 if (It != StreamMap.end())
20 return getRawStream(Streams[It->second]);
21 return std::nullopt;
22 }
23
getString(size_t Offset) const24 Expected<std::string> MinidumpFile::getString(size_t Offset) const {
25 // Minidump strings consist of a 32-bit length field, which gives the size of
26 // the string in *bytes*. This is followed by the actual string encoded in
27 // UTF16.
28 auto ExpectedSize =
29 getDataSliceAs<support::ulittle32_t>(getData(), Offset, 1);
30 if (!ExpectedSize)
31 return ExpectedSize.takeError();
32 size_t Size = (*ExpectedSize)[0];
33 if (Size % 2 != 0)
34 return createError("String size not even");
35 Size /= 2;
36 if (Size == 0)
37 return "";
38
39 Offset += sizeof(support::ulittle32_t);
40 auto ExpectedData =
41 getDataSliceAs<support::ulittle16_t>(getData(), Offset, Size);
42 if (!ExpectedData)
43 return ExpectedData.takeError();
44
45 SmallVector<UTF16, 32> WStr(Size);
46 copy(*ExpectedData, WStr.begin());
47
48 std::string Result;
49 if (!convertUTF16ToUTF8String(WStr, Result))
50 return createError("String decoding failed");
51
52 return Result;
53 }
54
55 iterator_range<llvm::object::MinidumpFile::ExceptionStreamsIterator>
getExceptionStreams() const56 MinidumpFile::getExceptionStreams() const {
57 return make_range(ExceptionStreamsIterator(ExceptionStreams, this),
58 ExceptionStreamsIterator({}, this));
59 }
60
61 Expected<iterator_range<MinidumpFile::MemoryInfoIterator>>
getMemoryInfoList() const62 MinidumpFile::getMemoryInfoList() const {
63 std::optional<ArrayRef<uint8_t>> Stream =
64 getRawStream(StreamType::MemoryInfoList);
65 if (!Stream)
66 return createError("No such stream");
67 auto ExpectedHeader =
68 getDataSliceAs<minidump::MemoryInfoListHeader>(*Stream, 0, 1);
69 if (!ExpectedHeader)
70 return ExpectedHeader.takeError();
71 const minidump::MemoryInfoListHeader &H = ExpectedHeader.get()[0];
72 Expected<ArrayRef<uint8_t>> Data =
73 getDataSlice(*Stream, H.SizeOfHeader, H.SizeOfEntry * H.NumberOfEntries);
74 if (!Data)
75 return Data.takeError();
76 return make_range(MemoryInfoIterator(*Data, H.SizeOfEntry),
77 MemoryInfoIterator({}, H.SizeOfEntry));
78 }
79
getDataSlice(ArrayRef<uint8_t> Data,uint64_t Offset,uint64_t Size)80 Expected<ArrayRef<uint8_t>> MinidumpFile::getDataSlice(ArrayRef<uint8_t> Data,
81 uint64_t Offset,
82 uint64_t Size) {
83 // Check for overflow.
84 if (Offset + Size < Offset || Offset + Size < Size ||
85 Offset + Size > Data.size())
86 return createEOFError();
87 return Data.slice(Offset, Size);
88 }
89
90 Expected<std::unique_ptr<MinidumpFile>>
create(MemoryBufferRef Source)91 MinidumpFile::create(MemoryBufferRef Source) {
92 ArrayRef<uint8_t> Data = arrayRefFromStringRef(Source.getBuffer());
93 auto ExpectedHeader = getDataSliceAs<minidump::Header>(Data, 0, 1);
94 if (!ExpectedHeader)
95 return ExpectedHeader.takeError();
96
97 const minidump::Header &Hdr = (*ExpectedHeader)[0];
98 if (Hdr.Signature != Header::MagicSignature)
99 return createError("Invalid signature");
100 if ((Hdr.Version & 0xffff) != Header::MagicVersion)
101 return createError("Invalid version");
102
103 auto ExpectedStreams = getDataSliceAs<Directory>(Data, Hdr.StreamDirectoryRVA,
104 Hdr.NumberOfStreams);
105 if (!ExpectedStreams)
106 return ExpectedStreams.takeError();
107
108 DenseMap<StreamType, std::size_t> StreamMap;
109 std::vector<Directory> ExceptionStreams;
110 for (const auto &StreamDescriptor : llvm::enumerate(*ExpectedStreams)) {
111 StreamType Type = StreamDescriptor.value().Type;
112 const LocationDescriptor &Loc = StreamDescriptor.value().Location;
113
114 Expected<ArrayRef<uint8_t>> Stream =
115 getDataSlice(Data, Loc.RVA, Loc.DataSize);
116 if (!Stream)
117 return Stream.takeError();
118
119 if (Type == StreamType::Unused && Loc.DataSize == 0) {
120 // Ignore dummy streams. This is technically ill-formed, but a number of
121 // existing minidumps seem to contain such streams.
122 continue;
123 }
124
125 // Exceptions can be treated as a special case of streams. Other streams
126 // represent a list of entities, but exceptions are unique per stream.
127 if (Type == StreamType::Exception) {
128 ExceptionStreams.push_back(StreamDescriptor.value());
129 continue;
130 }
131
132 if (Type == DenseMapInfo<StreamType>::getEmptyKey() ||
133 Type == DenseMapInfo<StreamType>::getTombstoneKey())
134 return createError("Cannot handle one of the minidump streams");
135
136 // Update the directory map, checking for duplicate stream types.
137 if (!StreamMap.try_emplace(Type, StreamDescriptor.index()).second)
138 return createError("Duplicate stream type");
139 }
140
141 return std::unique_ptr<MinidumpFile>(
142 new MinidumpFile(Source, Hdr, *ExpectedStreams, std::move(StreamMap),
143 std::move(ExceptionStreams)));
144 }
145
146 iterator_range<MinidumpFile::FallibleMemory64Iterator>
getMemory64List(Error & Err) const147 MinidumpFile::getMemory64List(Error &Err) const {
148 ErrorAsOutParameter ErrAsOutParam(Err);
149 auto end = FallibleMemory64Iterator::end(Memory64Iterator::end());
150 Expected<minidump::Memory64ListHeader> ListHeader = getMemoryList64Header();
151 if (!ListHeader) {
152 Err = ListHeader.takeError();
153 return make_range(end, end);
154 }
155
156 std::optional<ArrayRef<uint8_t>> Stream =
157 getRawStream(StreamType::Memory64List);
158 if (!Stream) {
159 Err = createError("No such stream");
160 return make_range(end, end);
161 }
162
163 Expected<ArrayRef<minidump::MemoryDescriptor_64>> Descriptors =
164 getDataSliceAs<minidump::MemoryDescriptor_64>(
165 *Stream, sizeof(Memory64ListHeader),
166 ListHeader->NumberOfMemoryRanges);
167
168 if (!Descriptors) {
169 Err = Descriptors.takeError();
170 return make_range(end, end);
171 }
172
173 if (!Descriptors->empty() &&
174 ListHeader->BaseRVA + Descriptors->front().DataSize > getData().size()) {
175 Err = createError("Memory64List header RVA out of range");
176 return make_range(end, end);
177 }
178
179 return make_range(FallibleMemory64Iterator::itr(
180 Memory64Iterator::begin(
181 getData().slice(ListHeader->BaseRVA), *Descriptors),
182 Err),
183 FallibleMemory64Iterator::end(Memory64Iterator::end()));
184 }
185