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diff --git a/docs/v2.4.0-ReleaseNotes b/docs/v2.4.0-ReleaseNotes new file mode 100644 index 0000000..2d70e0a --- /dev/null +++ b/docs/v2.4.0-ReleaseNotes @@ -0,0 +1,302 @@ +Cryptsetup 2.4.0 Release Notes +============================== +Stable release with new features and bug fixes. + +This version introduces support for external libraries +(plugins) for handling LUKS2 token objects. + +Changes since version 2.3.6 +~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +* External LUKS token plugins + + A LUKS2 token is an object that can describe how to get a passphrase + to unlock a particular keyslot. The generic metadata format is part + of the LUKS2 specification. + + Cryptsetup 2.4 adds the possibility to implement token handlers + in external libraries (possibly provided by other projects). + + A token library allows cryptsetup to understand metadata and provide + basic operations. Currently external tokens may be used to unlock + keyslots for following CLI actions: open (luksOpen), + refresh (open --refresh), resize and dump (prints token specific + content). + + LUKS2 devices cannot be resumed (luksResume action) via tokens yet. + Support for resume and other actions will be added later. + + The library now provides an interface that automatically tries to load + an external library for a token object in LUKS2 metadata. + + Token libraries should be installed in the cryptsetup subdirectory + (usually /lib*/cryptsetup). This path is configurable through + --with-luks2-external-tokens-path configure option. + + The external plugin loading can be compiled entirely out if + --disable-external-tokens configure option is used. The external token + interface can also be disabled runtime on the command line by + --disable-external-tokens cryptsetup switch or by calling + crypt_token_external_disable() API function. + + The name of the loaded token library is determined from the JSON LUKS + metadata token object type. For example, "ssh" token will load library + "libcryptsetup-token-ssh.so". + + External projects can use this interface to handle specific hardware + without introducing additional dependencies to libcryptsetup core. + + As of cryptsetup 2.4.0 release systemd project already merged upstream + native cryptsetup token handler for its systemd-tpm2 LUKS2 token + released originally in systemd-v248. The token can be created using + systemd-cryptenroll utility and devices may be manipulated either by + systemd-cryptsetup cli or by cryptsetup for actions listed above. + + Other tokens like systemd-fido2 and systemd-pkcs11 are currently + in-review. + +* Experimental SSH token + + As a demonstration of the external LUKS2 token interface, a new SSH + token handler and cryptsetup-ssh utility is now provided and compiled + by default. + + Crypsetup SSH token allows using remote keyfile through SSH protocol + (it will authenticate through SSH certificates). + + You can disable the build of this token library with + --disable-ssh-token configure option. + +To configure the token metadata, you need cryptsetup-ssh utility. + +Activation of the device is then performed by the cryptsetup utility. + +Example (how to activate LUKS2 through remote keyfile): + + - configure existing LUKS2 device with keyslot activated by a keyfile + # cryptsetup luksAddKey <device> keyfile --key-slot 2 + + - store that keyfile on a remote system accessible through SSH + + - configure SSH to use certificate for authentication + + - add a LUKS2 token with cryptsetup-ssh utility: + # cryptsetup-ssh add <device>1 --key-slot 2 \ + --ssh-server test-vm \ + --ssh-user test \ + --ssh-path /home/test/keyfile \ + --ssh-keypath /home/test/.ssh/test_rsa_key + + - you should see token metadata now with "cryptsetup luksDump ..." + ... + Tokens: + 0: ssh + ssh_server: test-vm + ssh_user: test + ssh_path: /home/test/keyfile + ssh_key_path: /home/test/.ssh/test_rsa_key + Keyslot: 2 + + + - activation now should be automatic + # cryptsetup open <device> test --verbose + SSH token initiating ssh session. + Key slot 2 unlocked. + Command successful. + + - to remove a token, you can use "cryptsetup token remove" command + (no plugin library required) + + Please note SSH token is just demonstration of plugin interface API, + it is an EXPERIMENTAL feature. + +* Add cryptsetup --token-type parameter. + + It restricts token type to the parameter value in case no specific + token-id is selected. + +* Support for token based activation with PIN. + + If specific token requires PIN to unlock keyslot passphrase and + --token-only parameter was used cryptsetup asks for additional + token PIN. + +* Respect keyslot priority with token-based activation. + +* Default LUKS2 PBKDF is now Argon2id + + Cryptsetup LUKS2 was using Argon2 while there were two versions, + data-independent (Argon2i) suitable for the KDF use case and + Argon2d (data-dependent). Later Argon2id was introduced as a new + mandatory algorithm. + + We switched the password-based key derivation algorithms + following the latest version of Argon2 RFC draft + (https://datatracker.ietf.org/doc/draft-irtf-cfrg-argon2/) to Argon2id + (from Argon2i) as it is the mandatory and primary version + of the Argon2 algorithm. + + There is no need to modify older containers; the main reason is that + RFC makes Argon2id the primary variant, while Argon2i subvariant is + only optional. + Argon2id provides better protection to side-channel attacks while + still providing protection to time-memory tradeoffs. + + We will switch to OpenSSL implementation once it is available. + With a crystal ball as a reference, it could happen early in + OpenSSL 3.1 release. + Watch https://github.com/openssl/openssl/issues/4091. + +* Increase minimal memory cost for Argon2 benchmark to 64MiB. + + This patch increases the benchmarking value to 64 MiB (as minimal + suggested values in Argon2 RFC). For compatibility reasons, we still + allow older limits if set by a parameter. + + NOTE: Argon2 RFC draft defines suggested parameters for disk + encryption, but the LUKS2 approach is slightly different. We need to + provide platform-independent values. The values in the draft expect + 64bit systems (suggesting using 6 GiB of RAM). In comparison, we need + to provide compatibility with all 32bit systems, so allocating more + than 4GiB memory is not an option for LUKS2. + + The maximal limit in LUKS2 stays for 4 GiB, and by default LUKS2 PBKDF + benchmarking sets maximum to 1 GIB, preferring an increase of CPU cost + while running benchmark + +* Autodetect optimal encryption sector size on LUKS2 format. + + While the support for larger encryption sectors is supported + for several releases, it required an additional parameter. + + Code now uses automatic detection of 4096-bytes native sector devices + and automatically enables 4096-bytes encryption size for LUKS2. + + If no setor size option is used, sector size is detected + automatically by cryptsetup. For libcryptsetup API, autodetection + happens once you specify sector_size to 0. + + NOTE: crypt_format() function runs autodetection ONLY if you + recompile your application to the new API symbol version. + For backward compatibility, older applications ignore this parameter. + +* Use VeraCrypt option by default and add --disable-veracrypt option. + + While TrueCrypt is no longer developed and supported since 2014, + VeraCrypt devices (a successor of TrueCrypt) are much more used today. + + Default is now to support VeraCrypt format (in addition to TrueCrypt), + making the --veracrypt option obsolete (ignored as it is the default). + + If you need to disable VeraCrypt support, use the new option + --disable-veracrypt. + + This option increases the time to recognize wrong passwords because + some VeraCrypt modes use a high PBKDF2 iteration count, and the code + must try all variants. This could be limited by using --hash and + --cipher options mentioned below. + +* Support --hash and --cipher to limit opening time for TCRYPT type + + If a user knows which particular PBKDF2 hash or cipher is used for + TrueCrypt/VeraCrypt container, TCRYPT format now supports --hash and + --cipher option. + + Note the value means substring (all cipher chains containing + the cipher substring are tried). + + For example, you can use + # cryptsetup tcryptDump --hash sha512 <container> + + Note: to speed up the scan, the hash option (used for PBKDF)2 matters. + Cipher variants are scanned very quickly. + + Use with care. + It can reveal some sensitive attributes of the container! + +* Fixed default OpenSSL crypt backend support for OpenSSL3. + + For OpenSSL version 3, we need to load legacy provider for older hash + and ciphers. For example, RIPEMD160 and Whirlpool hash algorithms are + no longer available by default. + + NOTE: the plain format still uses RIPEMD160 for password hashing by + default. Changing the default would cause incompatibilities for many + old systems. Nevertheless, such a change will be needed very soon. + +* integritysetup: add integrity-recalculate-reset flag. + + The new dm-integrity option in kernel 5.13 can restart recalculation + from the beginning of the device. + It can be used to change the integrity checksum function. + + New integritysetup --integrity-recalculate-reset option is added to + integritysetup, and CRYPT_ACTIVATE_RECALCULATE_RESET flag to API. + +* cryptsetup: retains keyslot number in luksChangeKey for LUKS2. + + In LUKS1, any change in keyslot means keyslot number change. + + In LUKS2, we can retain the keyslot number. + Now luksKeyChange and crypt_keyslot_change_by_passphrase() API + retains keyslot number for LUKS2 by default. + +* Fix cryptsetup resize using LUKS2 tokens. + + Fix a bug where cryptsetup needlessly asked for a passphrase even + though the volume key was already unlocked via LUKS2 token. + +* Add close --deferred and --cancel-deferred options. + + All command-line utilities now understand deferred options for the + close command. Deferred close means that the device is removed + automagically after the last user closed the device. + Cancel deferred means to cancel this operation (so the device remains + active even if there a no longer active users). + + CRYPT_DEACTIVATE_DEFERRED and CRYPT_DEACTIVATE_DEFERRED_CANCEL flags + are now available for API. + +* Rewritten command-line option parsing to avoid libpopt arguments + memory leaks. + + Note: some distributions use patched lipopt that still leaks memory + inside internal code (see Debian bug 941814). + +* Add --test-args option. + + New --test-args option can be used for syntax checking for valid + command-line arguments with no actions performed. + Note that it cannot detect unknown algorithm names and similar where + we need call API functions. + +* veritysetup: add --root-hash-file option + Allow passing the root hash via a file, rather than verbatim on + the command line, for the open, verify, and format actions. + +* libcryptsetup C API extensions (see libcryptsetup.h for details) + + - crypt_logf - a printf like log function + - crypt_dump_json - dump LUKS2 metadata in JSON format + - crypt_header_is_detached - check if context use detached header + - crypt_token_max - get maximal tokens number + - crypt_token_external_path - get path for plugins (or NULL) + - crypt_token_external_disable - disable runtime support for plugins + - crypt_activate_by_token_pin - activate by token with additional PIN + - crypt_reencrypt_run - fixed API for deprecated crypt_reencrypt + + The token plugin library interface cosists from these versioned + exported symbols (for details see header file and SSH token example): + cryptsetup_token_open + cryptsetup_token_open_pin + cryptsetup_token_buffer_free + cryptsetup_token_validate + cryptsetup_token_dump + cryptsetup_token_version + + Since version 2.4 libcryptsetup uses exact symbol versioning + Newly introduced functions have CRYPTSETUP_2.4 namespace (the old + symbol always used CRYPTSETUP_2.0). + There is no change in soname (the library is backward compatible). + + * Many fixes and additions to documentation and man pages. |