SMB3: Fix 3.11 encryption to Windows and handle encrypted smb3 tcon

Temporarily disable AES-GCM, as AES-CCM is only currently
enabled mechanism on client side.  This fixes SMB3.11
encrypted mounts to Windows.

Also the tree connect request itself should be encrypted if
requested encryption ("seal" on mount), in addition we should be
enabling encryption in 3.11 based on whether we got any valid
encryption ciphers back in negprot (the corresponding session flag is
not set as it is in 3.0 and 3.02)

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
This commit is contained in:
Steve French 2018-04-22 15:14:58 -05:00
parent 117e3b7fed
commit 23657ad730
3 changed files with 22 additions and 21 deletions

View File

@ -2959,6 +2959,22 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
}
}
if (volume_info->seal) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"SMB3 or later required for encryption\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else if (tcon->ses->server->capabilities &
SMB2_GLOBAL_CAP_ENCRYPTION)
tcon->seal = true;
else {
cifs_dbg(VFS, "Encryption is not supported on share\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
}
/*
* BB Do we need to wrap session_mutex around this TCon call and Unix
* SetFS as we do on SessSetup and reconnect?
@ -3007,22 +3023,6 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
tcon->use_resilient = true;
}
if (volume_info->seal) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"SMB3 or later required for encryption\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else if (tcon->ses->server->capabilities &
SMB2_GLOBAL_CAP_ENCRYPTION)
tcon->seal = true;
else {
cifs_dbg(VFS, "Encryption is not supported on share\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
}
/*
* We can have only one retry value for a connection to a share so for
* resources mounted more than once to the same server share the last

View File

@ -383,10 +383,10 @@ static void
build_encrypt_ctxt(struct smb2_encryption_neg_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_ENCRYPTION_CAPABILITIES;
pneg_ctxt->DataLength = cpu_to_le16(6);
pneg_ctxt->CipherCount = cpu_to_le16(2);
pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM;
pneg_ctxt->Ciphers[1] = SMB2_ENCRYPTION_AES128_CCM;
pneg_ctxt->DataLength = cpu_to_le16(4); /* Cipher Count + le16 cipher */
pneg_ctxt->CipherCount = cpu_to_le16(1);
/* pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM;*/ /* not supported yet */
pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_CCM;
}
static void
@ -444,6 +444,7 @@ static int decode_encrypt_ctx(struct TCP_Server_Info *server,
return -EINVAL;
}
server->cipher_type = ctxt->Ciphers[0];
server->capabilities |= SMB2_GLOBAL_CAP_ENCRYPTION;
return 0;
}

View File

@ -297,7 +297,7 @@ struct smb2_encryption_neg_context {
__le16 DataLength;
__le32 Reserved;
__le16 CipherCount; /* AES-128-GCM and AES-128-CCM */
__le16 Ciphers[2]; /* Ciphers[0] since only one used now */
__le16 Ciphers[1]; /* Ciphers[0] since only one used now */
} __packed;
struct smb2_negotiate_rsp {