-
-
Notifications
You must be signed in to change notification settings - Fork 0
/
VirusAnalysis.cxx
242 lines (230 loc) · 10.4 KB
/
VirusAnalysis.cxx
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/* Licenses: allows all uses ("Creative Commons"/"Apache 2") */
#ifndef INCLUDES_cxx_VirusAnalysis_cxx
#define INCLUDES_cxx_VirusAnalysis_cxx
#include <fstream> /* std::ifstream */
#include <vector> /* std::vector */
#include <string> /* std::string */
#include <tuple> /* std::tuple */
#include <algorithm> /* std::sort */
#include <utility> /* std::get */
#ifdef _POSIX_VERSION
#include <unistd.h> /* execve */
#endif /* _POSIX_VERSION */
#include "ClassSha2.hxx" /* Sha2 */
#include "ClassCns.hxx" /* Cns, CnsMode, posixExec */
#include "ClassResultList.hxx" /* listHas, ResultList, smallestUniqueSubstr */
#include "ClassPortableExecutable.hxx" /* PortableExecutable */
#include "VirusAnalysis.hxx" /* passList, abortList, *AnalyisCaches */
/* (Work-in-progress) virus analysis: uses hashes, signatures, static analysis, sandboxes, plus artificial CNS (central nervous systems) */
namespace Susuwu {
const bool virusAnalysisTestsThrows() {
ResultList abortOrNull {
.bytecodes { /* Produce from an antivirus vendor's (such as VirusTotal.com's) infection databases */
"infection",
"infectedSW",
"corruptedSW",
""
}
};
ResultList passOrNull {
.bytecodes { /* Produce from an antivirus vendor's (such as VirusTotal.com's) fresh-files databases */
"",
"SW",
"SW",
"newSW"
}
};
produceAbortListSignatures(passList, abortList);
produceAnalysisCns(passOrNull, abortOrNull, ResultList(), analysisCns);
produceDisinfectionCns(passOrNull, abortOrNull, disinfectionCns);
/* callbackHook("exec", */ [](const PortableExecutable &file) { /* TODO: OS-specific "hook"/"callback" for `exec()`/app-launches */
switch(virusAnalysis(file)) {
case virusAnalysisPass:
return true; /* launch this */
case virusAnalysisRequiresReview:
submitSampleToHosts(file); /* manual review */
return false;
default:
return false; /* abort */
}
} /* ) */ ;
return true;
}
const VirusAnalysisResult virusAnalysis(const PortableExecutable &file) {
const auto fileHash = Sha2(file.bytecode);
for(auto analysis : virusAnalyses) {
switch(analysis(file, fileHash)) {
case virusAnalysisPass:
return virusAnalysisPass;
case virusAnalysisRequiresReview:
/*submitSampleToHosts(file);*/ /* TODO:? up to caller to do this? */
return virusAnalysisRequiresReview;
case virusAnalysisAbort:
return virusAnalysisAbort;
default: /* virusAnalysisContinue */
}
}
return virusAnalysisPass;
}
const VirusAnalysisResult hashAnalysis(const ResultListHash &fileHash) {
try {
const auto result = hashAnalysisCaches.at(fileHash);
return result;
} catch (...) {
if(listHas(passList.hashes, fileHash)) {
return hashAnalysisCaches[fileHash] = virusAnalysisPass;
} else if(listHas(abortList.hashes, fileHash)) {
return hashAnalysisCaches[fileHash] = virusAnalysisAbort;
} else {
return hashAnalysisCaches[fileHash] = virusAnalysisContinue; /* continue to next tests */
}
}
}
const VirusAnalysisResult signatureAnalysis(const PortableExecutable &file, const ResultListHash &fileHash) {
try {
const auto result = signatureAnalysisCaches.at(fileHash);
return result;
} catch (...) {
for(auto sig : abortList.signatures) {
#if PREFERENCE_IS_CSTR
if(strstr(file.hex, sig)) { /* strstr uses text/hex; hex uses more space than binary, so you should use `memmem` or `std::search` with file.bytecode */
#else /* else !PREFERENCE_IS_CSTR */
if(file.bytecode.end() != std::search(file.bytecode.begin(), file.bytecode.end(), sig.begin(), sig.end())) {
#endif /* PREFERENCE_IS_CSTR else */
return signatureAnalysisCaches[fileHash] = virusAnalysisAbort;
}
}
return signatureAnalysisCaches[fileHash] = virusAnalysisContinue;
}
}
void produceAbortListSignatures(const ResultList &passList, ResultList &abortList) {
abortList.signatures.reserve(abortList.bytecodes.size());
for(auto file : abortList.bytecodes) {
auto tuple = smallestUniqueSubstr(file, passList.bytecodes);
abortList.signatures.push_back(ResultListSignature(std::get<0>(tuple), std::get<1>(tuple)));
} /* The most simple signature is a substring, but some analyses use regexes. */
}
const std::vector<std::string> importedFunctionsList(const PortableExecutable &file) {
/* TODO
* Resources; “Portable Executable” for Windows ( https://learn.microsoft.com/en-us/windows/win32/debug/pe-format https://wikipedia.org/wiki/Portable_Executable ,
* “Extended Linker Format” for most others such as UNIX/Linuxes ( https://wikipedia.org/wiki/Executable_and_Linkable_Format ),
* shows how to analyse lists of libraries(.DLL's/.SO's) the SW uses,
* plus what functions (new syscalls) the SW can goto through `jmp`/`call` instructions.
*
* "x86" instruction list for Intel/AMD ( https://wikipedia.org/wiki/x86 ),
* "aarch64" instruction list for most smartphones/tablets ( https://wikipedia.org/wiki/aarch64 ),
* shows how to analyse what OS functions the SW goes to without libraries (through `int`/`syscall`, old; most new SW uses `jmp`/`call`.)
* Plus, instructions lists show how to analyse what args the apps/SW pass to functions/syscalls (simple for constant args such as "push 0x2; call functions;",
* but if registers/addresses as args such as "push eax; push [address]; call [address2];" must guess what is *"eax"/"[address]"/"[address2]", or use sandboxes.
*
* https://www.codeproject.com/Questions/338807/How-to-get-list-of-all-imported-functions-invoked shows how to analyse dynamic loads of functions (if do this, `syscallPotentialDangers[]` does not include `GetProcAddress()`.)
*/
}
const VirusAnalysisResult staticAnalysis(const PortableExecutable &file, const ResultListHash &fileHash) {
try {
const auto result = staticAnalysisCaches.at(fileHash);
return result;
} catch (...) {
auto syscallsUsed = importedFunctionsList(file);
std::sort(syscallPotentialDangers.begin(), syscallPotentialDangers.end());
std::sort(syscallsUsed.begin(), syscallsUsed.end());
if(listsIntersect(syscallPotentialDangers, syscallsUsed)) {
return staticAnalysisCaches[fileHash] = virusAnalysisRequiresReview;
}
return staticAnalysisCaches[fileHash] = virusAnalysisContinue;
}
}
const VirusAnalysisResult sandboxPass(const PortableExecutable &file, const ResultListHash &fileHash) {
try {
const auto result = sandboxAnalysisCaches.at(fileHash);
return result;
} catch (...) {
posixExec("/bin/cp", "-r '/usr/home/sandbox/' '/usr/home/sandbox.bak'"); /* or produce FS snapshot */
posixExec("/bin/cp", "'" + file.path + "' '/usr/home/sandbox/'");
posixExec("/bin/chroot", "'/usr/home/sandbox/' \"strace basename '" + file.path + "'\" >> strace.outputs");
posixExec("/bin/mv/", "'/usr/home/sandbox/strace.outputs' '/tmp/strace.outputs'");
posixExec("/bin/sh", "-c 'rm -r /usr/home/sandbox/ && mv /usr/home/sandbox.bak /usr/home/sandbox/'"); /* or restore FS snapshot */
return sandboxAnalysisCaches[fileHash] = straceOutputsAnalysis("/tmp/strace.outputs");
}
}
const VirusAnalysisResult straceOutputsAnalysis(const char *straceDumpPath) {
auto straceDump = std::ifstream(straceDumpPath);
std::vector<std::string> straceOutputs /*= explodeToList(straceDump, "\n")*/;
for(std::string straceOutput; std::getline(straceDump, straceOutput); ) {
straceOutputs.push_back(straceOutput);
}
std::sort(stracePotentialDangers.begin(), stracePotentialDangers.end());
std::sort(straceOutputs.begin(), straceOutputs.end());
if(listsIntersect(stracePotentialDangers, straceOutputs)) { /* Todo: regex */
return virusAnalysisRequiresReview;
}
return virusAnalysisContinue;
}
void produceAnalysisCns(const ResultList &pass, const ResultList &abort,
const ResultList &unreviewed /* = ResultList(), WARNING! Possible danger to use unreviewed samples */,
Cns &cns /* = analysisCns */
) {
std::vector<const std::tuple<const FileBytecode, float>> inputsToOutputs;
const size_t maxPassSize = maxOfSizes(pass.bytecodes);
const size_t maxAbortSize = maxOfSizes(abort.bytecodes);
cns.setInputMode(cnsModeString);
cns.setOutputMode(cnsModeFloat);
cns.setInputNeurons(maxPassSize > maxAbortSize ? maxPassSize : maxAbortSize);
cns.setOutputNeurons(1);
cns.setLayersOfNeurons(6666);
cns.setNeuronsPerLayer(26666);
inputsToOutputs.reserve(pass.bytecodes.size());
for(auto bytecodes : pass.bytecodes) {
inputsToOutputs.push_back({bytecodes, 1.0});
}
cns.setupSynapses(inputsToOutputs);
inputsToOutputs.clear();
if(unreviewed.bytecodes.size()) { /* WARNING! Possible danger to use unreviewed samples */
inputsToOutputs.reserve(unreviewed.bytecodes.size());
for(auto bytecodes : unreviewed.bytecodes) {
inputsToOutputs.push_back({bytecodes, 1 / 2});
}
cns.setupSynapses(inputsToOutputs);
inputsToOutputs.clear();
}
inputsToOutputs.reserve(abort.bytecodes.size());
for(auto bytecodes : abort.bytecodes) {
inputsToOutputs.push_back({bytecodes, 0.0});
}
cns.setupSynapses(inputsToOutputs);
inputsToOutputs.clear();
}
const float cnsAnalysisScore(const PortableExecutable &file, const Cns &cns /* = analysisCns */) {
return cns.processToFloat(file.bytecode);
}
const VirusAnalysisResult cnsAnalysis(const PortableExecutable &file, const ResultListHash &fileHash, const Cns &cns /* = analysisCns */) {
try {
const auto result = cnsAnalysisCaches.at(fileHash);
return result;
} catch (...) {
return cnsAnalysisCaches[fileHash] = (bool)round(cnsAnalysisScore(file, cns)) ? virusAnalysisContinue : virusAnalysisRequiresReview;
}
}
void produceDisinfectionCns(const ResultList &passOrNull, const ResultList &abortOrNull, Cns &cns /* = disinfectionCns */) {
std::vector<const std::tuple<const FileBytecode, const FileBytecode>> inputsToOutputs;
cns.setInputMode(cnsModeString);
cns.setOutputMode(cnsModeString);
cns.setInputNeurons(maxOfSizes(passOrNull.bytecodes));
cns.setOutputNeurons(maxOfSizes(abortOrNull.bytecodes));
cns.setLayersOfNeurons(6666);
cns.setNeuronsPerLayer(26666);
assert(passOrNull.bytecodes.size() == abortOrNull.bytecodes.size());
inputsToOutputs.reserve(passOrNull.bytecodes.size());
for(int x = 0; passOrNull.bytecodes.size() > x; ++x) {
inputsToOutputs.push_back({abortOrNull.bytecodes[x], passOrNull.bytecodes[x]});
}
cns.setupSynapses(inputsToOutputs);
}
const FileBytecode cnsDisinfection(const PortableExecutable &file, const Cns &cns /* = disinfectionCns */) {
return cns.processToString(file.bytecode);
}
/* To process fast (lag less,) use flags which auto-vectorizes/auto-parallelizes; To do `produce*Cns` fast, use TensorFlow's `MapReduce`;
* https://swudususuwu.substack.com/p/howto-run-devices-phones-laptops
*/
}; /* namespace Susuwu */
#endif /* ndef INCLUDES_cxx_VirusAnalysis_cxx */