Introduce the NETWORK_ISCSI_MD5_ENABLE feature test macro for NetworkPkg.
When explicitly set to FALSE, remove MD5 from IScsiDxe's CHAP algorithm
list.
Set NETWORK_ISCSI_MD5_ENABLE to TRUE by default, for compatibility
reasons. Not just to minimize the disruption for platforms that currently
include IScsiDxe, but also because RFC 7143 mandates MD5 for CHAP, and
some vendors' iSCSI targets support MD5 only.
With MD5 enabled, IScsiDxe will suggest SHA256, and then fall back to MD5
if the target requests it. With MD5 disabled, IScsiDxe will suggest
SHA256, and break off the connection (and session) if the target doesn't
support SHA256.
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3355
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210629163337.14120-7-lersek@redhat.com>
Introduce the "mChapHash" table, containing the hash algorithms supported
for CHAP. Hash algos listed at the beginning of the table are preferred by
the initiator.
In ISCSI_CHAP_STEP_ONE, send such a CHAP_A value that is the
comma-separated, ordered list of algorithm identifiers from "mChapHash".
Pre-format this value string at driver startup, in the new function
IScsiCHAPInitHashList().
(In IScsiCHAPInitHashList(), also enforce that every hash algo's digest
size fit into ISCSI_CHAP_MAX_DIGEST_SIZE, as the latter controls the
digest, outgoing challenge, and hex *allocations*.)
In ISCSI_CHAP_STEP_TWO, allow the target to select one of the offered hash
algorithms, and remember the selection for the later steps. For
ISCSI_CHAP_STEP_THREE, hash the challenge from the target with the
selected hash algo.
In ISCSI_CHAP_STEP_THREE, send the correctly sized digest to the target.
If the initiator wants mutual authentication, then generate a challenge
with as many bytes as the target's digest will have, in
ISCSI_CHAP_STEP_FOUR.
In ISCSI_CHAP_STEP_FOUR (i.e., when mutual authentication is required by
the initiator), verify the target's response (digest) with the selected
algorithm.
Clear the selected hash algorithm before every login (remember that in
IScsiDxe, every login is a leading login).
There is no peer-observable change from this patch, as it only reworks the
current MD5 support into the new internal representation.
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3355
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20210629163337.14120-5-lersek@redhat.com>
Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
IScsiDxe uses the ISCSI_CHAP_RSP_LEN macro for expressing the size of the
digest (16) that it solely supports at this point (MD5).
ISCSI_CHAP_RSP_LEN is used for both (a) *allocating* digest-related
buffers (binary buffers and hex encodings alike), and (b) *processing*
binary digest buffers (comparing them, filling them, reading them).
In preparation for adding other hash algorithms, split purpose (a) from
purpose (b). For purpose (a) -- buffer allocation --, introduce
ISCSI_CHAP_MAX_DIGEST_SIZE. For purpose (b) -- processing --, rely on
MD5_DIGEST_SIZE from <BaseCryptLib.h>.
Distinguishing these purposes is justified because purpose (b) --
processing -- must depend on the hashing algorithm negotiated between
initiator and target, while for purpose (a) -- allocation --, using the
maximum supported digest size is suitable. For now, because only MD5 is
supported, introduce ISCSI_CHAP_MAX_DIGEST_SIZE *as* MD5_DIGEST_SIZE.
Note that the argument for using the digest size as the size of the
outgoing challenge (in case mutual authentication is desired by the
initiator) remains in place. Because of this, the above two purposes are
distinguished for the "ISCSI_CHAP_AUTH_DATA.OutChallenge" field as well.
This patch is functionally a no-op, just yet.
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3355
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Message-Id: <20210629163337.14120-4-lersek@redhat.com>
IScsiDxe (that is, the initiator) receives two hex-encoded strings from
the iSCSI target:
- CHAP_C, where the target challenges the initiator,
- CHAP_R, where the target answers the challenge from the initiator (in
case the initiator wants mutual authentication).
Accordingly, we have two IScsiHexToBin() call sites:
- At the CHAP_C decoding site, check whether the decoding succeeds. The
decoded buffer ("AuthData->InChallenge") can accommodate 1024 bytes,
which is a permissible restriction on the target, per
<https://tools.ietf.org/html/rfc7143#section-12.1.3>. Shorter challenges
from the target are acceptable.
- At the CHAP_R decoding site, enforce that the decoding both succeed, and
provide exactly ISCSI_CHAP_RSP_LEN bytes. CHAP_R contains the digest
calculated by the target, therefore it must be of fixed size. We may
only call IScsiCHAPAuthTarget() if "TargetRsp" has been fully populated.
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3356
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Message-Id: <20210608121259.32451-11-lersek@redhat.com>
The "ISCSI_CHAP_AUTH_DATA.OutChallenge" field is declared as a UINT8 array
with ISCSI_CHAP_AUTH_MAX_LEN (1024) elements. However, when the challenge
is generated and formatted, only ISCSI_CHAP_RSP_LEN (16) octets are used
in the array.
Change the array size to ISCSI_CHAP_RSP_LEN, and remove the (now unused)
ISCSI_CHAP_AUTH_MAX_LEN macro.
Remove the "ISCSI_CHAP_AUTH_DATA.OutChallengeLength" field, which is
superfluous too.
Most importantly, explain in a new comment *why* tying the challenge size
to the digest size (ISCSI_CHAP_RSP_LEN) has always made sense. (See also
Linux kernel commit 19f5f88ed779, "scsi: target: iscsi: tie the challenge
length to the hash digest size", 2019-11-06.) For sure, the motivation
that the new comment now explains has always been there, and has always
been the same, for IScsiDxe; it's just that now we spell it out too.
No change in peer-visible behavior.
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3356
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Message-Id: <20210608121259.32451-4-lersek@redhat.com>
1. Do not use tab characters
2. No trailing white space in one line
3. All files must end with CRLF
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
