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Krypterar du Windows "fullsystem kryptering" HDD så installeras en boot-loader som du ser vid uppstarten där du matar in lösenordet. Jag menade att du kan inte ta bort boot-loadern och samtidigt ha kvar krypteringen då lär datorn inte hitta något OS att boota från.
Ursprungligen postat av anonium
Okej låter betryggande. Dock nämner du företrädesvis extern hårddisk, hur är det med datorns inbyggda systemdisk.
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Precis som att Windows försöker läsa en HDD du kopplar till och läsa in filsystemet. Misslyckas det kommer du få ett felmeddelande. TC försöker också om det går att läsa HDD och misslyckas det så kommer du inte in helt enkelt. Vad jag förstått är det alltså inget lösenord det matchas mot utan den använder lösenordet och en del av första sektorn på HDD:n för att framställa en kryptonyckel. Nyckeln är alltid på 256, 512 eller 768-bitar så för du inte ska vara tvingad ha den längden på varje lösenord finns en rest på första sektorn.
Ursprungligen postat av MF-Data
Klart det finns på disken, hur skulle den krypterade disken.
Ifall lösenordet inte finns på disken hur fungerar det då?
Ifall lösenordet inte finns på disken hur fungerar det då?
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Header key is used to encrypt and decrypt the encrypted area of the TrueCrypt volume header (for system encryption, of the keydata area), which contains the master key and other data (see the sections Encryption Scheme and TrueCrypt Volume Format Specification). In volumes created by TrueCrypt 5.0 or later (and for system encryption), the area is encrypted in XTS mode (see the section Modes of Operation). The method that TrueCrypt uses to generate the header key and the secondary header key (XTS mode) is PBKDF2, specified in PKCS #5 v2.0; see [7].
Header keys used by ciphers in a cascade are mutually independent, even though they are derived from a single password (to which keyfiles may have been applied). For example, for the AES-Twofish-Serpent cascade, the header key derivation function is instructed to derive a 768-bit encryption key from a given password (and, for XTS mode, in addition, a 768-bit secondary header key from the given password). The generated 768-bit header key is then split into three 256-bit keys (for XTS mode, the secondary header key is split into three 256-bit keys too, so the cascade actually uses six 256-bit keys in total), out of which the first key is used by Serpent, the second key is used by Twofish, and the third by AES (in addition, for XTS mode, the first secondary key is used by Serpent, the second secondary key is used by Twofish, and the third secondary key by AES). Hence, even when an adversary has one of the keys, he cannot use it to derive the other keys, as there is no feasible method to determine the password from which the key was derived (except for brute force attack mounted on a weak password).
Header keys used by ciphers in a cascade are mutually independent, even though they are derived from a single password (to which keyfiles may have been applied). For example, for the AES-Twofish-Serpent cascade, the header key derivation function is instructed to derive a 768-bit encryption key from a given password (and, for XTS mode, in addition, a 768-bit secondary header key from the given password). The generated 768-bit header key is then split into three 256-bit keys (for XTS mode, the secondary header key is split into three 256-bit keys too, so the cascade actually uses six 256-bit keys in total), out of which the first key is used by Serpent, the second key is used by Twofish, and the third by AES (in addition, for XTS mode, the first secondary key is used by Serpent, the second secondary key is used by Twofish, and the third secondary key by AES). Hence, even when an adversary has one of the keys, he cannot use it to derive the other keys, as there is no feasible method to determine the password from which the key was derived (except for brute force attack mounted on a weak password).
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Senast redigerad av E.Helgetun 2013-01-22 kl. 10:46.
Senast redigerad av E.Helgetun 2013-01-22 kl. 10:46.
