Add PluginLoader class

- PluginLoader::verify can be used to check if the plugin has a valid
(SHA512/RSA 4096) signature.
- Uses nn OpenSSL public key that is embedded during the compile.

5 files changed, 101 insertions, 4 deletions

diff --git a/src/browser.cpp b/src/browser.cpp
index 69db6b2..db75fa1 100644
--- a/src/browser.cpp
+++ b/src/browser.cpp
@@ -38,6 +38,7 @@
 #include "adblock/adblocklist.h"
 #include "hostlist/hostlist.h"
 #include <spdlog/spdlog.h>
+#include "plugin/pluginloader.h"
 
 Browser::Browser(int &argc, char *argv[], bool allowSecondary)
     : SingleApplication(argc, argv, allowSecondary, SingleApplication::User | SingleApplication::SecondaryNotification | SingleApplication::ExcludeAppVersion)
@@ -150,7 +151,8 @@ QPluginLoader *Browser::addPlugin(const QString &path)
     if(path.isEmpty())
         return nullptr;
 
-    auto *loader = new QPluginLoader(path, this);
+    auto *loader = new PluginLoader(path, this);
+    spdlog::info("Verifying plugin: {}", loader->verify() ? "passed" : "failed");
     loader->load();
 
     auto *info = new PluginInfo(loader);
diff --git a/src/main.cpp b/src/main.cpp
index dfe58de..0d6f466 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -18,6 +18,7 @@
 #include <QFile>
 #include <QLibraryInfo>
 #include <QPluginLoader>
+#include "plugin/pluginloader.h"
 #include <QTranslator>
 #include <memory>
 #include <plugininterface.h>
@@ -69,8 +70,9 @@ int main(int argc, char **argv)
     CommandHash_t pluginCommands;
 
     // Load plugins
-    for(const QString &path : Util::files(config->value<QString>("plugins.path").value())) {
-        auto *loader = new QPluginLoader(path);
+    for(const QString &path : Util::files(config->value<QString>("plugins.path").value(), {"*.so", "*.dll"})) {
+        auto *loader = new PluginLoader(path);
+        spdlog::info("Verifying plugin: {}", loader->verify() ? "passed" : "failed");
         const bool loaded = loader->load();
         spdlog::info("{} plugin {}", loaded ? "Loaded" : "Failed to load", qUtf8Printable(path));
 
diff --git a/src/meson.build b/src/meson.build
index ef0f989..960cc69 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -1,6 +1,7 @@
 # poi
 poi_moc = mod_qt5.preprocess(
     moc_headers: ['browser.h',
+        'plugin/pluginloader.h',
         'mainwindow/mainwindow.h', 'mainwindow/menubar.h', 'mainwindow/widgets/dockwidget.h', 'mainwindow/widgets/menusearch.h', 'mainwindow/widgets/navigationbar.h', 'mainwindow/widgets/searchform.h',
         'session/savesessiondialog.h', 'session/sessiondialog.h', 'session/sessionform.h',
         'subwindow/subwindow.h', 'subwindow/tabwidget.h',
@@ -13,13 +14,15 @@ poi_moc = mod_qt5.preprocess(
 
 poi = executable(get_option('poiName'), install: true,
     cpp_args: ['-DQAPPLICATION_CLASS=QApplication'],
-    dependencies: [dep_qt5, dep_boost, dep_spdlog, dep_SingleApplication, dep_genheaders, optional_deps,
+    dependencies: [dep_qt5, dep_boost, dep_spdlog, dep_openssl, dep_SingleApplication, dep_genheaders, optional_deps,
         dep_about, dep_addressbar, dep_bookmarks, dep_configuration, dep_downloads, dep_urlfilter, dep_webprofile],
     include_directories: [include],
     sources: ['main.cpp', 'builtins.cpp', 'crashhandler.cpp', poi_moc,
     'browser.cpp',
     'util.cpp', 'util.h',
 
+    'plugin/pluginloader.cpp',
+
     'mainwindow/mainwindow.cpp',
     'mainwindow/menubar.cpp',
     'mainwindow/widgets/dockwidget.cpp',
diff --git a/src/plugin/pluginloader.cpp b/src/plugin/pluginloader.cpp
new file mode 100644
index 0000000..d1626f2
--- /dev/null
+++ b/src/plugin/pluginloader.cpp
@@ -0,0 +1,77 @@
+#include "pluginloader.h"
+#include <QFile>
+#include <openssl/evp.h>
+#include <openssl/pem.h>
+#include "publicKey.h"
+#include <spdlog/spdlog.h>
+
+PluginLoader::PluginLoader(const QString &fileName, QObject *parent)
+    : QPluginLoader(fileName, parent)
+{
+}
+
+bool PluginLoader::verify(const char *hashName) const
+{
+    const QString sigName = this->fileName() + ".sig";
+    if(!QFile::exists(sigName)) {
+        spdlog::error("Signature does not exist: {}", qUtf8Printable(sigName));
+        return false;
+    }
+
+    auto *bio = BIO_new_mem_buf(publicKey_pem, publicKey_pem_len);
+    Q_CHECK_PTR(bio);
+
+    auto *key = PEM_read_bio_PUBKEY(bio, NULL, NULL, NULL);
+    Q_CHECK_PTR(key);
+
+    auto *ctx = EVP_MD_CTX_new();
+    Q_CHECK_PTR(ctx);
+
+    const auto *md = EVP_get_digestbyname(hashName);
+    Q_CHECK_PTR(md);
+
+    int rc = EVP_DigestVerifyInit(ctx, NULL, md, NULL, key);
+    if(rc != 1) {
+        spdlog::error("DigestVerifyInit failed: %i", rc);
+        return false;
+    }
+
+    // read plugin into DigestVerifyUpdate
+    QFile plugin(this->fileName());
+    plugin.open(QIODevice::ReadOnly);
+    int len = plugin.size();
+    int read = 0;
+    auto *buf = new unsigned char[1024];
+    while(len > 0) {
+        read = plugin.read((char*) buf, 1024);
+        len -= read;
+
+        rc = EVP_DigestVerifyUpdate(ctx, buf, read);
+        if(rc != 1)
+            spdlog::error("DigestVerifyUpdate failed: %i", rc);
+    }
+    delete buf;
+    plugin.close();
+
+    // read signature into DigestVerifyFinal
+    QFile sigFile(sigName);
+    sigFile.open(QIODevice::ReadOnly);
+    const int sig_len = sigFile.size();
+    const auto* sig = [&sigFile, sig_len]() {
+        auto* buf = new unsigned char[sig_len];
+        sigFile.read((char*) buf, sig_len);
+        return buf;
+    }();
+    sigFile.close();
+
+    rc = EVP_DigestVerifyFinal(ctx, sig, sig_len);
+    delete sig;
+
+    if(rc == 1)
+        return true;
+    else {
+        spdlog::error("DigestVerifyFinal failed: %i", rc);
+        return false;
+    }
+}
+
diff --git a/src/plugin/pluginloader.h b/src/plugin/pluginloader.h
new file mode 100644
index 0000000..8d186aa
--- /dev/null
+++ b/src/plugin/pluginloader.h
@@ -0,0 +1,13 @@
+#include <QPluginLoader>
+
+class PluginLoader : public QPluginLoader
+{
+    Q_OBJECT
+
+public:
+    PluginLoader(const QString &fileName, QObject *parent = nullptr);
+    ~PluginLoader() = default;
+
+    bool verify(const char *hashName = "SHA256") const;
+};
+