ImHex/source/views/view_information.cpp

139 lines
5.1 KiB
C++

#include "views/view_information.hpp"
#include "providers/provider.hpp"
#include "utils.hpp"
#include <algorithm>
#include <vector>
#include <cstring>
#include <cmath>
#include <magic.h>
#include <span>
namespace hex {
ViewInformation::ViewInformation(prv::Provider* &dataProvider) : View(), m_dataProvider(dataProvider) {
View::subscribeEvent(Events::DataChanged, [this](void*) {
this->m_shouldInvalidate = true;
});
}
ViewInformation::~ViewInformation() {
View::unsubscribeEvent(Events::DataChanged);
}
static float calculateEntropy(std::array<float, 256> &valueCounts, size_t numBytes) {
float entropy = 0;
for (u16 i = 0; i < 256; i++) {
valueCounts[i] /= numBytes;
if (valueCounts[i] > 0)
entropy -= (valueCounts[i] * std::log2(valueCounts[i]));
}
return entropy / 8;
}
void ViewInformation::createView() {
if (!this->m_windowOpen)
return;
if (ImGui::Begin("File Information", &this->m_windowOpen)) {
ImGui::BeginChild("##scrolling", ImVec2(0, 0), false, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoNav);
if (this->m_dataProvider != nullptr && this->m_dataProvider->isReadable()) {
if (this->m_shouldInvalidate) {
{
std::vector<u8> buffer(512, 0x00);
std::memset(this->m_valueCounts.data(), 0x00, this->m_valueCounts.size() * sizeof(u32));
this->m_blockEntropy.clear();
for (u64 i = 0; i < this->m_dataProvider->getSize(); i += 512) {
std::array<float, 256> blockValueCounts = { 0 };
this->m_dataProvider->read(i, buffer.data(), std::min(512ULL, this->m_dataProvider->getSize() - i));
for (u16 j = 0; j < 512; j++) {
blockValueCounts[buffer[j]]++;
this->m_valueCounts[buffer[j]]++;
}
this->m_blockEntropy.push_back(calculateEntropy(blockValueCounts, 512));
}
this->m_averageEntropy = calculateEntropy(this->m_valueCounts, this->m_dataProvider->getSize());
this->m_highestBlockEntropy = *std::max_element(this->m_blockEntropy.begin(), this->m_blockEntropy.end());
}
{
std::vector<u8> buffer(this->m_dataProvider->getSize(), 0x00);
this->m_dataProvider->read(0x00, buffer.data(), buffer.size());
{
magic_t cookie = magic_open(MAGIC_NONE);
magic_load(cookie, "magic");
this->m_fileDescription = magic_buffer(cookie, buffer.data(), buffer.size());
magic_close(cookie);
}
{
magic_t cookie = magic_open(MAGIC_MIME);
magic_load(cookie, "magic");
this->m_mimeType = magic_buffer(cookie, buffer.data(), buffer.size());
magic_close(cookie);
}
this->m_shouldInvalidate = false;
}
}
ImGui::NewLine();
ImGui::Text("Byte Distribution");
ImGui::PlotHistogram("##nolabel", this->m_valueCounts.data(), 256, 0, nullptr, FLT_MAX, FLT_MAX, ImVec2(0, 100));
ImGui::NewLine();
ImGui::Separator();
ImGui::NewLine();
ImGui::Text("Entropy");
ImGui::PlotLines("##nolabel", this->m_blockEntropy.data(), this->m_blockEntropy.size(), 0, nullptr, FLT_MAX, FLT_MAX, ImVec2(0, 100));
ImGui::NewLine();
ImGui::LabelText("Average entropy", "%.8f", this->m_averageEntropy);
ImGui::LabelText("Highest entropy block", "%.8f", this->m_highestBlockEntropy);
if (this->m_averageEntropy > 0.83 && this->m_highestBlockEntropy > 0.9) {
ImGui::NewLine();
ImGui::TextColored(ImVec4(0.92F, 0.25F, 0.2F, 1.0F), "This data is most likely encrypted or compressed!");
}
ImGui::NewLine();
ImGui::Separator();
ImGui::NewLine();
ImGui::TextUnformatted("Description:");
ImGui::TextWrapped("%s", this->m_fileDescription.c_str());
ImGui::NewLine();
ImGui::TextUnformatted("MIME Type:");
ImGui::TextWrapped("%s", this->m_mimeType.c_str());
ImGui::NewLine();
}
ImGui::EndChild();
}
ImGui::End();
}
void ViewInformation::createMenu() {
if (ImGui::BeginMenu("View")) {
ImGui::MenuItem("Entropy View", "", &this->m_windowOpen);
ImGui::EndMenu();
}
}
}