Make msgenc store encryption keys in gmm files

tools/msgenc/Gmm.cpp

@@ -1,6 +1,7 @@
 #include "Gmm.h"
 #include "pugixml.hpp"
 #include <regex>
+#include <string>
 
 static const char WINCTXNAME[] = "window_context_name";
 static const char LANGUAGE[] = "English";
@@ -68,7 +69,7 @@ void GMM::WriteGmmHeader(const string &_filename) {
 }
 
 // Reads messages from GMM into memory to be converted
-void GMM::FromFile(MessagesConverter &converter) {
+int GMM::FromFile(MessagesConverter &converter) {
     pugi::xml_parse_result result = doc.load(stream);
     if (!result) {
         throw runtime_error(result.description());
@@ -77,6 +78,7 @@ void GMM::FromFile(MessagesConverter &converter) {
         return strcmp(n.name(), "body") == 0;
     });
     int i = 0;
+    int key = GMM_KEY_NOT_DEFINED;
     string rowname_pref = filename.substr(filename.find_last_of('/') + 1).substr(0, filename.find_first_of('.'));
     for (const auto &subnode : node.children()) {
         if (strcmp(subnode.name(), "row") == 0) {
@@ -105,10 +107,16 @@ void GMM::FromFile(MessagesConverter &converter) {
             i++;
             IncRowNoBuf();
         }
+        if (strcmp(subnode.name(), "key") == 0) {
+            key = stoi(subnode.attribute("value").value(), nullptr, 0);
+            key &= 0xFFFF;
+            key |= 0x10000;
+        }
     }
     if (!converter.GetHeaderFilename().empty()) {
         WriteGmmHeader(converter.GetHeaderFilename());
     }
+    return key;
 }
 
 // Writes decoded messages to a new GMM file
@@ -124,6 +132,10 @@ void GMM::ToFile(MessagesConverter &converter) {
     }
     string rowname_pref = filename.substr(filename.find_last_of('/') + 1);
     rowname_pref = rowname_pref.substr(0, rowname_pref.find_first_of('.'));
+
+    auto key = body.append_child("key");
+    key.append_attribute("value").set_value(std::to_string(converter.GetKey()).c_str());
+
     int i = 0;
     for (const auto &message : converter.GetDecodedMessages()) {
         string rowname;

tools/msgenc/Gmm.h

@@ -19,6 +19,8 @@
 #include "pugixml.hpp"
 #include "MessagesConverter.h"
 
+#define GMM_KEY_NOT_DEFINED -1
+
 class GMM {
     static const int _row_no_buf_ndigit = 5;
     char row_no_buf[_row_no_buf_ndigit + 1] = {0};
@@ -46,7 +48,7 @@ public:
     GMM(string &_filename, ios::openmode _openmode) : filename(_filename), stream(_filename, _openmode) {
         memset(row_no_buf, '0', _row_no_buf_ndigit);
     }
-    void FromFile(MessagesConverter &converter);
+    int FromFile(MessagesConverter &converter);
     void ToFile(MessagesConverter &converter);
 
 private:

tools/msgenc/MessagesEncoder.cpp

@@ -30,7 +30,14 @@ void MessagesEncoder::ReadMessagesFromText(string& fname) {
 }
 
 void MessagesEncoder::ReadMessagesFromGMM(string& filename) {
-    GMM(filename, std::ios::in).FromFile(*this);
+    int key_from_file = GMM(filename, std::ios::in).FromFile(*this);
+
+    // If key has been specified in the gmm, use 
+    // that instead of the command-line value
+    if (key_from_file != GMM_KEY_NOT_DEFINED) {
+        header.key = key_from_file;
+    }
+
     header.count = vec_decoded.size();
     debug_printf("%d lines\n", header.count);
 }