check for 16 bytes boundary before encryption

This commit is contained in:
orignal 2014-04-18 14:38:32 -04:00
parent 4cbc7773ac
commit 607f2d29f2
2 changed files with 5 additions and 4 deletions

View File

@ -483,7 +483,7 @@ namespace ntcp
*((uint16_t *)sendBuffer) = 0;
*((uint32_t *)(sendBuffer + 2)) = htobe32 (time (0));
}
int rem = (len + 6) % 16;
int rem = (len + 6) & 0x0F; // %16
int padding = 0;
if (rem > 0) padding = 16 - rem;
// TODO: fill padding

View File

@ -506,6 +506,7 @@ namespace ssu
uint8_t * encrypted = &header->flag;
uint16_t encryptedLen = len - (encrypted - buf);
m_Encryption.SetKeyWithIV (aesKey, 32, iv);
encryptedLen = (encryptedLen>>4)<<4; // make sure 16 bytes boundary
m_Encryption.ProcessData (encrypted, encrypted, encryptedLen);
// assume actual buffer size is 18 (16 + 2) bytes more
memcpy (buf + len, iv, 16);
@ -524,7 +525,7 @@ namespace ssu
uint8_t * encrypted = &header->flag;
uint16_t encryptedLen = len - (encrypted - buf);
m_Decryption.SetKeyWithIV (aesKey, 32, header->iv);
encryptedLen = (encryptedLen/16)*16; // make sure 16 bytes boundary
encryptedLen = (encryptedLen>>4)<<4; // make sure 16 bytes boundary
m_Decryption.ProcessData (encrypted, encrypted, encryptedLen);
}
@ -953,8 +954,8 @@ namespace ssu
memcpy (payload, msgBuf, size);
size += payload - buf;
if (size % 16) // make sure 16 bytes boundary
size = (size/16 + 1)*16;
if (size & 0x0F) // make sure 16 bytes boundary
size = ((size >> 4) + 1) << 4; // (/16 + 1)*16
CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
rnd.GenerateBlock (iv, 16); // random iv