update// added some stuff

src/Crypto/FileEncryption.cpp

@@ -7,42 +7,48 @@ void FileEncryption::showConfig()
 
 int FileEncryption::encrypt(QString target_file, QString source_file, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES])
 {
-    unsigned char  buf_in[FILEENCRYPTION_CHUNK_SIZE];
-    unsigned char  buf_out[FILEENCRYPTION_CHUNK_SIZE + crypto_secretstream_xchacha20poly1305_ABYTES];
+    unsigned char  plain_data[FILEENCRYPTION_CHUNK_SIZE];
+    unsigned char  cipher_data[FILEENCRYPTION_CHUNK_SIZE + crypto_secretstream_xchacha20poly1305_ABYTES];
     unsigned char  header[crypto_secretstream_xchacha20poly1305_HEADERBYTES];
-    crypto_secretstream_xchacha20poly1305_state st;
-    FILE          *fp_t, *fp_s;
-    unsigned long long out_len;
+    crypto_secretstream_xchacha20poly1305_state state;
+    FILE          *target, *source;
+    unsigned long long cipher_len;
     size_t         rlen;
     int            eof;
     unsigned char  tag;
 
-    fp_s = fopen(source_file.toStdString().c_str(), "rb");
-    fp_t = fopen(target_file.toStdString().c_str(), "wb");
-    crypto_secretstream_xchacha20poly1305_init_push(&st, header, key);
-    fwrite(header, 1, sizeof header, fp_t);
+    if(!FileEncryption::exists(source_file.toStdString()))
+    {
+        qDebug() << "File not exits" << source_file;
+        return -1;
+    }
+
+    source = fopen(source_file.toStdString().c_str(), "rb");
+    target = fopen(target_file.toStdString().c_str(), "wb");
+    crypto_secretstream_xchacha20poly1305_init_push(&state, header, key);
+    fwrite(header, 1, sizeof header, target);
     do 
     {
-        rlen = fread(buf_in, 1, sizeof buf_in, fp_s);
-        eof = feof(fp_s);
+        rlen = fread(plain_data, 1, sizeof plain_data, source);
+        eof = feof(source);
         tag = eof ? crypto_secretstream_xchacha20poly1305_TAG_FINAL : 0;
         crypto_secretstream_xchacha20poly1305_push(
-            &st, 
-            buf_out, 
-            &out_len, 
-            buf_in, 
+            &state, 
+            cipher_data, 
+            &cipher_len, 
+            plain_data, 
             rlen,
             NULL, 
             0, 
             tag
         );
 
-        fwrite(buf_out, 1, (size_t) out_len, fp_t);
+        fwrite(cipher_data, 1, (size_t) cipher_len, target);
     } 
     while (! eof);
 
-    fclose(fp_t);
-    fclose(fp_s);
+    fclose(target);
+    fclose(source);
     return 0;
 }
 
@@ -59,6 +65,12 @@ int FileEncryption::decrypt(QString target_file, QString source_file, const unsi
     int            ret = -1;
     unsigned char  tag;
 
+    if(!FileEncryption::exists(source_file.toStdString()))
+    {
+        qDebug() << "File not exits" << source_file;
+        return -1;
+    }
+
     fp_s = fopen(source_file.toStdString().c_str(), "rb");
     fp_t = fopen(target_file.toStdString().c_str(), "wb");
     fread(header, 1, sizeof header, fp_s);

src/Crypto/FileEncryption.h

@@ -3,11 +3,17 @@
 #include <stdio.h>
 #include <sodium.h>
 #include <QString>
+#include <fstream>
 
 #define FILEENCRYPTION_CHUNK_SIZE 4096
 
 class FileEncryption
 {
+    private:
+        inline static bool exists (const std::string& name) {
+            std::ifstream f(name.c_str());
+            return f.good();
+        }
     public:
         static void showConfig();
         static int encrypt(QString target_file, QString source_file, const unsigned char key[crypto_secretstream_xchacha20poly1305_KEYBYTES]);

src/Crypto/passwd.cpp

@@ -0,0 +1,39 @@
+#include "passwd.h"
+
+void PASSWD::show_hex_buff(unsigned char buf[])
+{
+    int i;
+    for (uint8_t i=0; i < crypto_secretstream_xchacha20poly1305_KEYBYTES; i++) 
+        printf("%02X ", buf[i]);
+    printf("\n");
+}
+
+const unsigned char* PASSWD::hash(QString password)
+{
+    /*std::string data = password.toStdString();
+    
+    unsigned char hash[crypto_generichash_BYTES];
+
+    crypto_generichash(hash, sizeof hash,
+                    (const unsigned char*)data.c_str(), data.size(),
+                    NULL, 0);
+
+    //qDebug() << PASSWD::convertToHexString(hash);
+    return (const unsigned char*)hash;*/
+
+    int length = password.length();
+     
+    char *sequence = NULL;
+    sequence = new char[length+1];
+    strncpy(sequence, password.toLocal8Bit(), length +1);
+
+    #define MESSAGE ((const unsigned char *) sequence)
+    #define MESSAGE_LEN length
+
+    qDebug()<<"Generating cryptographic key from password: " <<sequence;
+    unsigned char * hash= new unsigned char[crypto_secretstream_xchacha20poly1305_KEYBYTES];
+    crypto_generichash(hash, sizeof hash, MESSAGE, MESSAGE_LEN, NULL, 0);
+    qDebug()<<"secret key generated:\n";
+    PASSWD::show_hex_buff(hash);
+    return hash;
+}

src/Crypto/passwd.h

@@ -0,0 +1,14 @@
+#ifndef PASSWD_H
+#define PASSWD_H
+#include <stdio.h>
+#include <sodium.h>
+#include <QString>
+
+class PASSWD
+{
+    public:
+        static void show_hex_buff(unsigned char buf[]);
+        static const unsigned char* hash(QString);
+};
+
+#endif