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AES encrypt/decrypt works
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IV is now in the beginning of the files
regex on IV works
check size of IV
QLineEdit max size for IV is set
need to consider IV as hex not ASCII
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@QuentinGouchet
QuentinGouchet committed Feb 28, 2016
1 parent de82869 commit 5c734a9
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Showing 6 changed files with 84 additions and 39 deletions.
42 changes: 29 additions & 13 deletions src/aes.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -48,8 +48,8 @@ int AES::generateKey(unsigned int nbits, const char *root_keys)
return err;
}

int AES::aes_cbc_128_encrypt(const char *plaintextPath, const char *key,
const char *cipherPath, const char *iv)
int AES::aes_cbc_128_encrypt(const char *plaintextPath, const char *cipherPath,
const char *key, const char *iv)
{
FILE *plaintextFile = NULL;
FILE *ciphertextFile = NULL;
Expand Down Expand Up @@ -126,8 +126,8 @@ int AES::aes_cbc_128_encrypt(const char *plaintextPath, const char *key,

fileContent[plaintext_len] = 0x10;

fprintf(stdout, "FileContent: ");
print.printBuff(fileContent, ciphertext_len);
//fprintf(stdout, "FileContent: ");
//print.printBuff(fileContent, ciphertext_len);

err = gcry_cipher_open(&hd, GCRY_CIPHER_AES128, GCRY_CIPHER_MODE_CBC, 0);
if(err)
Expand Down Expand Up @@ -158,8 +158,8 @@ int AES::aes_cbc_128_encrypt(const char *plaintextPath, const char *key,

err = gcry_cipher_encrypt(hd, fileContent, ciphertext_len, NULL, 0);

fprintf(stdout, "FileContent: ");
print.printBuff(fileContent, ciphertext_len);
//fprintf(stdout, "FileContent: ");
//print.printBuff(fileContent, ciphertext_len);

if(err)
{
Expand All @@ -181,6 +181,14 @@ int AES::aes_cbc_128_encrypt(const char *plaintextPath, const char *key,

printf("%s\n", pathCipherFile);

// start by writing the 16 bytes IV in the file
if(16 != fwrite(iv, 1, 16, ciphertextFile))
{
err = 1;
fprintf(stderr, "Could not write IV into cipher file\n");
goto out;
}

if(ciphertext_len != fwrite(fileContent, 1, ciphertext_len, ciphertextFile))
{
err = 1;
Expand All @@ -203,34 +211,33 @@ int AES::aes_cbc_128_encrypt(const char *plaintextPath, const char *key,
return err;
}

int AES::aes_cbc_128_decrypt(const char *ciphertextPath, const char *key,
const char *plaintextPath, const char *iv)
int AES::aes_cbc_128_decrypt(const char *ciphertextPath, const char *plaintextPath, const char *key)
{
FILE *plaintextFile = NULL;
FILE *ciphertextFile = NULL;

int blklen = gcry_cipher_get_algo_blklen(GCRY_CIPHER_AES128);

unsigned char *fileContent = NULL;
unsigned char *ciphertext = NULL;
//unsigned char *ciphertext = NULL;

char pathPlainFile[50];

long fsize = 0;
int plaintext_len, ciphertext_len, i;
int plaintext_len, ciphertext_len;

gcry_cipher_hd_t hd = NULL;
gcry_error_t err = 0;

Util print;

printf("iv: ");
print.printBuff((unsigned char *)iv, blklen);
printf("key: ");
print.printBuff((unsigned char *)key, blklen);

printf("ciphertextpath: %s\n", ciphertextPath);

unsigned char *iv = (unsigned char *) gcry_malloc(blklen*sizeof(unsigned char));

if((ciphertextFile = fopen(ciphertextPath, "r")) == NULL)
{
err = 1;
Expand All @@ -252,7 +259,7 @@ int AES::aes_cbc_128_decrypt(const char *ciphertextPath, const char *key,
goto out;
}

ciphertext_len = fsize;
ciphertext_len = fsize - blklen;

fprintf(stdout, "ciphertext: %d\n", ciphertext_len);

Expand All @@ -271,6 +278,13 @@ int AES::aes_cbc_128_decrypt(const char *ciphertextPath, const char *key,
goto out;
}

if(fread(iv, 1, blklen, ciphertextFile) != blklen)
{
err = 1;
fprintf(stderr, "fread() failure on ciphertext file\n");
goto out;
}

if(fread(fileContent, 1, ciphertext_len, ciphertextFile) != ciphertext_len)
{
err = 1;
Expand Down Expand Up @@ -368,6 +382,8 @@ int AES::aes_cbc_128_decrypt(const char *ciphertextPath, const char *key,
fclose(ciphertextFile);
if(fileContent)
gcry_free(fileContent);
/*if(iv)
gcry_free(iv);*/
return err;
}

Expand Down
2 changes: 1 addition & 1 deletion src/aes.h
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Original file line number Diff line number Diff line change
Expand Up @@ -22,7 +22,7 @@ class AES
AES();
int generateKey(unsigned int, const char *);
int aes_cbc_128_encrypt(const char *, const char *, const char *, const char *);
int aes_cbc_128_decrypt(const char *, const char *, const char *, const char *);
int aes_cbc_128_decrypt(const char *, const char *, const char *);
int aes_cbc_256_encrypt(const char *, const char *, const char *, const char *);
int aes_cbc_256_decrypt(const char *, const char *, const char *, const char *);
};
Expand Down
63 changes: 46 additions & 17 deletions src/cipher.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -92,6 +92,13 @@ Cipher::Cipher(int index, int public_cipher): QDialog()
gl->addWidget(comboSize, 2, 2);

gl->addWidget(labelIv, 3, 0);

// index == 4 is AES; we want a 128 bits IV only
if(index == 4)
leIv->setMaxLength(gcry_cipher_get_algo_blklen(GCRY_CIPHER_AES));
// index = 5 3DES, IV is 64 bits
else if(index == 5)
leIv->setMaxLength(gcry_cipher_get_algo_blklen(GCRY_CIPHER_3DES));
gl->addWidget(leIv, 3, 1);
gl->addWidget(radioIv, 3, 2);

Expand Down Expand Up @@ -379,33 +386,42 @@ void Cipher::computeAES(){
// Next line is not needed since we derive the key from the passphrase
// reKey = new QRegExp("^[\\w|/]+\\.(key)$");

reIv = new QRegExp("[a-fA-F0-9]+");

// Let's derive the key given by the password
if( (leKey->text().isEmpty() || lePlain->text().isEmpty() || leCipher->text().isEmpty() || leIv->text().size() != 16) )
{
mb = new QMessageBox(this);
mb->setWindowTitle("Information");
mb->setText("One field is still empty!");
mb->exec();
return ;
}

fprintf(stdout, "passphrase: %s\n", leKey->text().toLocal8Bit().constData());
fprintf(stdout, "size in bytes: %d\n", comboSize->currentText().toInt()/8);

int keylen = comboSize->currentText().toLocal8Bit().toInt()/8;
int pass_len = leKey->text().length();

// Here check whether adioIv is checked and if not randomly generate IV and store in the file
/*unsigned char *iv;
int ivSize = comboSize->currentText().toInt();
if(!radioIv->isChecked())
// Here check whether radioIv is checked and if not randomly generate IV and store in the file
unsigned char *iv = NULL;
int ivSize = 16;
if(!radioIv->isChecked())
{
iv = (unsigned char *) malloc(ivSize*sizeof(unsigned char));
gcry_randomize(&iv, ivSize, GCRY_STRONG_RANDOM);
iv = (unsigned char *) gcry_malloc(ivSize*sizeof(unsigned char));
gcry_randomize(iv, ivSize, GCRY_STRONG_RANDOM);
Util print;
print.printBuff(iv, ivSize);
}
else
iv = (unsigned char *) leIv->text().toLocal8Bit().constData();

printf("we pass here\n");*/



fprintf(stdout, "size of pass: %d\n", pass_len);

Util print;
printf("iv: ");
print.printBuff(iv, ivSize);

int hash_len = gcry_md_get_algo_dlen(GCRY_MD_SHA256);

Expand Down Expand Up @@ -440,23 +456,31 @@ void Cipher::computeAES(){
QLineEdit contienne bien une extension .in pour le fichier d'entrée, une extension .out pour le fi-
chier de sortie et une extension .key pour le fichier de clé
*/
if(!reIv->exactMatch(leIv->text()))
{
mb = new QMessageBox(this);
mb->setText("The IV field is incorrect");
mb->setWindowTitle("Information");
mb->exec();
return ;
}

if(reCipher->exactMatch(leCipher->text()))
{
aes = new AES();

if(!(strcmp(comboMode->currentText().toLocal8Bit().constData(), "CBC") ||
strcmp(comboSize->currentText().toLocal8Bit().constData(), "128")))
{
printf("AES128 encryption\n");
printf("AES-128-CBC encryption\n");
rep = aes->aes_cbc_128_encrypt(lePlain->text().toLocal8Bit().constData(),
(const char *) pass,
leCipher->text().toLocal8Bit().constData(),
leIv->text().toLocal8Bit().constData());
leCipher->text().toLocal8Bit().constData(),
(const char *) pass, (const char*) iv);
}
else if(!(strcmp(comboMode->currentText().toLocal8Bit().constData(), "CBC") ||
strcmp(comboSize->currentText().toLocal8Bit().constData(), "256")))
{
printf("AES256 encryption\n");
printf("AES-256 encryption\n");
rep = aes->aes_cbc_256_encrypt(lePlain->text().toLocal8Bit().constData(),
(const char *) pass,
leCipher->text().toLocal8Bit().constData(),
Expand Down Expand Up @@ -502,11 +526,16 @@ void Cipher::computeAES(){
}

// not actually needed, it is done by derivePassphrase
// why is gcry_free(pass) failing?
out:
if(hd)

if(hd)
gcry_md_close(hd);
return ;
/* if(hd)
gcry_md_close(hd);
if(pass)
gcry_free(pass);
gcry_free(pass);*/
/*if(iv)
free(iv);*/
}
Expand Down
1 change: 1 addition & 0 deletions src/cipher.h
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Original file line number Diff line number Diff line change
Expand Up @@ -57,6 +57,7 @@ class Cipher : public QDialog
QRegExp *rePlain;
QRegExp *reCipher;
QRegExp *reKey;
QRegExp *reIv;

QMessageBox *mb;

Expand Down
15 changes: 7 additions & 8 deletions src/decipher.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@ Decipher::Decipher(int index, int public_cipher): QDialog()
else
labelKey = new QLabel("Type in your passphrase :", this);
labelMode = new QLabel("Block chaining mode and size :");
labelIv = new QLabel("Enter IV :", this);
//labelIv = new QLabel("Enter IV :", this);

buttonBrowseCipher = new QPushButton("Browse", this);
if(public_cipher)
Expand All @@ -46,7 +46,7 @@ Decipher::Decipher(int index, int public_cipher): QDialog()
if(!public_cipher)
leKey->setEchoMode(QLineEdit::Password);

leIv = new QLineEdit(this);
//leIv = new QLineEdit(this);

fdCipher = new QFileDialog(this);
fdKey = new QFileDialog(this);
Expand Down Expand Up @@ -82,8 +82,8 @@ Decipher::Decipher(int index, int public_cipher): QDialog()
gl->addWidget(comboMode, 2, 1);
gl->addWidget(comboSize, 2, 2);

gl->addWidget(labelIv, 3, 0);
gl->addWidget(leIv, 3, 1);
/*gl->addWidget(labelIv, 3, 0);
gl->addWidget(leIv, 3, 1);*/

gl->addWidget(labelPlain, 4, 0);
gl->addWidget(lePlain, 4, 1);
Expand Down Expand Up @@ -459,11 +459,10 @@ void Decipher::computeAES()
if(!(strcmp(comboMode->currentText().toLocal8Bit().constData(), "CBC") ||
strcmp(comboSize->currentText().toLocal8Bit().constData(), "128")))
{
printf("AES128 decryption\n");
printf("AES-128-CBC decryption\n");
rep = aes->aes_cbc_128_decrypt(leCipher->text().toLocal8Bit().constData(),
(const char *) pass,
lePlain->text().toLocal8Bit().constData(),
leIv->text().toLocal8Bit().constData());
lePlain->text().toLocal8Bit().constData(),
(const char *) pass);
}
else if(!(strcmp(comboMode->currentText().toLocal8Bit().constData(), "CBC") ||
strcmp(comboSize->currentText().toLocal8Bit().constData(), "256")))
Expand Down
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