linux-cifs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Aurélien Aptel" <aaptel@suse.com>
To: linux-cifs@vger.kernel.org
Cc: smfrench@gmail.com, metze@samba.org, Aurelien Aptel <aaptel@suse.com>
Subject: [PATCH v1 1/2] cifs: set server->cipher_type to AES-128-CCM for SMB3.0
Date: Fri, 21 May 2021 17:19:27 +0200	[thread overview]
Message-ID: <20210521151928.17730-2-aaptel@suse.com> (raw)
In-Reply-To: <20210521151928.17730-1-aaptel@suse.com>

From: Aurelien Aptel <aaptel@suse.com>

SMB3.0 doesn't have encryption negotiate context but simply uses
the SMB2_GLOBAL_CAP_ENCRYPTION flag.

When that flag is present in the neg response cifs.ko uses AES-128-CCM
which is the only cipher available in this context.

cipher_type was set to the server cipher only when parsing encryption
negotiate context (SMB3.1.1).

For SMB3.0 it was set to 0. This means cipher_type value can be 0 or 1
for AES-128-CCM.

Fix this by checking for SMB3.0 and encryption capability and setting
cipher_type appropriately.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
---
 fs/cifs/smb2pdu.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 9f24eb88297a..c205f93e0a10 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -958,6 +958,13 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 	/* Internal types */
 	server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;
 
+	/*
+	 * SMB3.0 supports only 1 cipher and doesn't have a encryption neg context
+	 * Set the cipher type manually.
+	 */
+	if (server->dialect == SMB30_PROT_ID && (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION))
+		server->cipher_type = SMB2_ENCRYPTION_AES128_CCM;
+
 	security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
 					       (struct smb2_sync_hdr *)rsp);
 	/*
-- 
2.31.1


  reply	other threads:[~2021-05-21 15:19 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-21 15:19 [PATCH v1 0/2] Change CIFS_FULL_KEY_DUMP ioctl to return variable size keys Aurélien Aptel
2021-05-21 15:19 ` Aurélien Aptel [this message]
2021-05-21 18:39   ` [PATCH v1 1/2] cifs: set server->cipher_type to AES-128-CCM for SMB3.0 Steve French
2021-05-28  8:37     ` Aurélien Aptel
2021-05-27 20:23   ` Steve French
2021-05-21 15:19 ` [PATCH v1 2/2] cifs: change format of CIFS_FULL_KEY_DUMP ioctl Aurélien Aptel
2021-05-21 19:47   ` Steve French
2021-05-21 15:42 ` [PATCH v1 0/2] Change CIFS_FULL_KEY_DUMP ioctl to return variable size keys Paulo Alcantara

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210521151928.17730-2-aaptel@suse.com \
    --to=aaptel@suse.com \
    --cc=linux-cifs@vger.kernel.org \
    --cc=metze@samba.org \
    --cc=smfrench@gmail.com \
    --subject='Re: [PATCH v1 1/2] cifs: set server->cipher_type to AES-128-CCM for SMB3.0' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).