Public/VeraCrypt
1
0
Fork 0
mirror of https://github.com/veracrypt/VeraCrypt.git synced 2025-11-11 11:08:02 -06:00
Code Activity

Security: ensure that XTS primary key is different from secondary key when creating volumes

Browse Source 
This is unlikely to happen thanks to random generator properties but we much add this check to prevent an attack described in page 3 of https://csrc.nist.gov/csrc/media/Projects/crypto-publication-review-project/documents/initial-comments/sp800-38e-initial-public-comments-2021.pdf
This commit is contained in:
Mounir IDRASSI
2023-08-05 10:55:46 +02:00
parent e8f83544ea
commit 16bb1de3a6
2 changed files with 14 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
src/Common/Volumes.c
View File

@@ -909,6 +909,15 @@ int CreateVolumeHeaderInMemory (HWND hwndDlg, BOOL bBoot, char *header, int ea,
retVal = ERR_CIPHER_INIT_WEAK_KEY; retVal = ERR_CIPHER_INIT_WEAK_KEY;
goto err; goto err;
} }
// check that first half of keyInfo.master_keydata is different from the second half. If they are the same return error
// cf CCSS,NSA comment at page 3: https://csrc.nist.gov/csrc/media/Projects/crypto-publication-review-project/documents/initial-comments/sp800-38e-initial-public-comments-2021.pdf
if (memcmp (keyInfo.master_keydata, &keyInfo.master_keydata[bytesNeeded/2], bytesNeeded/2) == 0)
{
crypto_close (cryptoInfo);
retVal = ERR_CIPHER_INIT_WEAK_KEY;
goto err;
}
} }
else else
{ {

5
src/Core/VolumeCreator.cpp
View File

@@ -298,6 +298,11 @@ namespace VeraCrypt
// Master data key // Master data key
MasterKey.Allocate (options->EA->GetKeySize() * 2); MasterKey.Allocate (options->EA->GetKeySize() * 2);
RandomNumberGenerator::GetData (MasterKey); RandomNumberGenerator::GetData (MasterKey);
// check that first half of MasterKey is different from its second half. If they are the same, through an exception
// cf CCSS,NSA comment at page 3: https://csrc.nist.gov/csrc/media/Projects/crypto-publication-review-project/documents/initial-comments/sp800-38e-initial-public-comments-2021.pdf
if (memcmp (MasterKey.Ptr(), MasterKey.Ptr() + MasterKey.Size() / 2, MasterKey.Size() / 2) == 0)
throw AssertionFailed (SRC_POS);
headerOptions.DataKey = MasterKey; headerOptions.DataKey = MasterKey;
// PKCS5 salt // PKCS5 salt