1 files changed, 227 insertions, 0 deletions
diff --git a/src/mso/encryption_info.cpp b/src/mso/encryption_info.cpp
new file mode 100644
index 0000000..bca2bcd
--- /dev/null
+++ b/src/mso/encryption_info.cpp
@@ -0,0 +1,227 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include <orcus/sax_ns_parser.hpp>
+#include <orcus/xml_namespace.hpp>
+#include <orcus/base64.hpp>
+
+#include "mso/encryption_info.hpp"
+
+#define ORCUS_DEBUG_MSO_ENCRYPTION_INFO 1
+
+#if ORCUS_DEBUG_MSO_ENCRYPTION_INFO
+#include <iostream>
+#endif
+
+#include <vector>
+#include <ostream>
+
+using namespace std;
+
+namespace orcus { namespace mso {
+
+namespace {
+
+const xmlns_id_t NS_mso_encryption = "http://schemas.microsoft.com/office/2006/encryption";
+const xmlns_id_t NS_mso_password = "http://schemas.microsoft.com/office/2006/keyEncryptor/password";
+
+const xmlns_id_t NS_mso_all[] = {
+    NS_mso_encryption,
+    NS_mso_password,
+    nullptr
+};
+
+class char_printer
+{
+    ostream& m_os;
+public:
+    char_printer(ostream& os) : m_os(os) {}
+    void operator() (const char c) const
+    {
+        short v = c;
+        v &= 0x00FF;
+        m_os << hex << uppercase;
+        if (v < 16)
+            m_os << '0';
+        m_os << v << ' ';
+    }
+};
+
+void print_base64(const char* caption, std::string_view base64)
+{
+    cout << caption << " (base64): " << base64 << endl;
+    vector<uint8_t> value = orcus::decode_from_base64(base64);
+    cout << caption << " (binary): ";
+    for_each(value.begin(), value.end(), char_printer(cout));
+    cout << endl;
+}
+
+class key_data_attr_handler
+{
+public:
+    void operator() (const sax_ns_parser_attribute& attr)
+    {
+        if (attr.ns != NS_mso_encryption)
+            // wrong namespace
+            return;
+
+        if (attr.name == "saltSize")
+            cout << "salt size: " << attr.value << endl;
+        else if (attr.name == "blockSize")
+            cout << "block size: " << attr.value << endl;
+        else if (attr.name == "keyBits")
+            cout << "key bits: " << attr.value << endl;
+        else if (attr.name == "hashSize")
+            cout << "hash size: " << attr.value << endl;
+        else if (attr.name == "cipherAlgorithm")
+            cout << "cipher algorithm: " << attr.value << endl;
+        else if (attr.name == "cipherChaining")
+            cout << "cipher chaining: " << attr.value << endl;
+        else if (attr.name == "hashAlgorithm")
+            cout << "hash algorithm: " << attr.value << endl;
+        else if (attr.name == "saltValue")
+            print_base64("salt value", attr.value);
+    }
+};
+
+class data_integrity_attr_handler
+{
+public:
+    void operator() (const sax_ns_parser_attribute& attr)
+    {
+        if (attr.ns != NS_mso_encryption)
+            // wrong namespace
+            return;
+
+        if (attr.name == "encryptedHmacKey")
+            print_base64("encrypted HMAC key", attr.value);
+        else if (attr.name == "encryptedHmacValue")
+            print_base64("encrypted HMAC value", attr.value);
+    }
+};
+
+class password_encrypted_key_attr_handler
+{
+public:
+    void operator() (const sax_ns_parser_attribute& attr)
+    {
+        if (attr.ns != NS_mso_encryption)
+            // wrong namespace
+            return;
+
+        if (attr.name == "spinCount")
+            cout << "spin count: " << attr.value << endl;
+        else if (attr.name == "saltSize")
+            cout << "salt size: " << attr.value << endl;
+        else if (attr.name == "blockSize")
+            cout << "block size: " << attr.value << endl;
+        else if (attr.name == "keyBits")
+            cout << "key bits: " << attr.value << endl;
+        else if (attr.name == "hashSize")
+            cout << "hash size: " << attr.value << endl;
+        else if (attr.name == "cipherAlgorithm")
+            cout << "cipher algorithm: " << attr.value << endl;
+        else if (attr.name == "cipherChaining")
+            cout << "cipher chaining: " << attr.value << endl;
+        else if (attr.name == "hashAlgorithm")
+            cout << "hash algorithm: " << attr.value << endl;
+        else if (attr.name == "saltValue")
+            print_base64("salt value", attr.value);
+        else if (attr.name == "encryptedVerifierHashInput")
+            print_base64("encrypted verifier hash input", attr.value);
+        else if (attr.name == "encryptedVerifierHashValue")
+            print_base64("encrypted verifier hash value", attr.value);
+        else if (attr.name == "encryptedKeyValue")
+            print_base64("encrypted key value", attr.value);
+
+    }
+};
+
+class sax_handler
+{
+    vector<sax_ns_parser_attribute> m_attrs;
+
+public:
+    sax_handler(xmlns_context& /*ns_cxt*/) {}
+    void doctype(const sax::doctype_declaration&) {}
+    void start_declaration(std::string_view) {}
+    void end_declaration(std::string_view) {}
+    void attribute(std::string_view, std::string_view) {}
+
+    void attribute(const sax_ns_parser_attribute& attr)
+    {
+        m_attrs.push_back(attr);
+    }
+
+    void characters(std::string_view, bool) {}
+
+    void start_element(const sax_ns_parser_element& elem)
+    {
+        if (elem.ns == NS_mso_encryption)
+        {
+            if (elem.name == "keyData")
+            {
+                cout << "--- key data" << endl;
+                key_data_attr_handler func;
+                for_each(m_attrs.begin(), m_attrs.end(), func);
+            }
+            else if (elem.name == "dataIntegrity")
+            {
+                cout << "--- data integrity" << endl;
+                data_integrity_attr_handler func;
+                for_each(m_attrs.begin(), m_attrs.end(), func);
+            }
+        }
+        else if (elem.ns == NS_mso_password)
+        {
+            if (elem.name == "encryptedKey")
+            {
+                cout << "--- encrypted key" << endl;
+                password_encrypted_key_attr_handler func;
+                for_each(m_attrs.begin(), m_attrs.end(), func);
+            }
+        }
+
+        m_attrs.clear();
+    }
+
+    void end_element(const sax_ns_parser_element&) {}
+};
+
+}
+
+struct encryption_info_reader_impl
+{
+    orcus::xmlns_repository m_ns_repo;
+
+    encryption_info_reader_impl()
+    {
+        m_ns_repo.add_predefined_values(NS_mso_all);
+    }
+};
+
+encryption_info_reader::encryption_info_reader() :
+    mp_impl(new encryption_info_reader_impl) {}
+
+encryption_info_reader::~encryption_info_reader()
+{
+    delete mp_impl;
+}
+
+void encryption_info_reader::read(const char* p, size_t n)
+{
+#if ORCUS_DEBUG_MSO_ENCRYPTION_INFO
+    cout << "encryption_info_reader::read: stream size=" << n << endl;
+#endif
+    orcus::xmlns_context cxt = mp_impl->m_ns_repo.create_context();
+    sax_handler hdl(cxt);
+    orcus::sax_ns_parser<sax_handler> parser({p, n}, cxt, hdl);
+    parser.parse();
+}
+
+}}
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */