From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 99FBF482E5; Wed, 20 Dec 2023 16:11:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="07I6C86g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E1B2C433C7; Wed, 20 Dec 2023 16:11:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1703088694; bh=/2mAhGIrgsV56ow387Ety1su+T5fB0QrXNRJ+fZOy8Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=07I6C86gu5Y8hjmhUy8GLJKJznFqnKTq2YpIo0BRqvUZD6Z1YNH1pA5rKlo/ZDkR4 eyqiNN7XdcDl98hg9OziPenEWXjlP9Qgk591TE//XpD7tkJsgvUyCztAu8MbKVlOOH 5IH/Tseh5mqonJahu3sDrdpyjKUYgbQPuIgYGRDo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Namjae Jeon , Steve French Subject: [PATCH 5.15 024/159] ksmbd: add support for key exchange Date: Wed, 20 Dec 2023 17:08:09 +0100 Message-ID: <20231220160932.404226580@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231220160931.251686445@linuxfoundation.org> References: <20231220160931.251686445@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Namjae Jeon [ Upstream commit f9929ef6a2a55f03aac61248c6a3a987b8546f2a ] When mounting cifs client, can see the following warning message. CIFS: decode_ntlmssp_challenge: authentication has been weakened as server does not support key exchange To remove this warning message, Add support for key exchange feature to ksmbd. This patch decrypts 16-byte ciphertext value sent by the client using RC4 with session key. The decrypted value is the recovered secondary key that will use instead of the session key for signing and sealing. Signed-off-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/ksmbd/auth.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) --- a/fs/ksmbd/auth.c +++ b/fs/ksmbd/auth.c @@ -29,6 +29,7 @@ #include "mgmt/user_config.h" #include "crypto_ctx.h" #include "transport_ipc.h" +#include "../smbfs_common/arc4.h" /* * Fixed format data defining GSS header and fixed string @@ -342,6 +343,29 @@ int ksmbd_decode_ntlmssp_auth_blob(struc nt_len - CIFS_ENCPWD_SIZE, domain_name, conn->ntlmssp.cryptkey); kfree(domain_name); + + /* The recovered secondary session key */ + if (conn->ntlmssp.client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) { + struct arc4_ctx *ctx_arc4; + unsigned int sess_key_off, sess_key_len; + + sess_key_off = le32_to_cpu(authblob->SessionKey.BufferOffset); + sess_key_len = le16_to_cpu(authblob->SessionKey.Length); + + if (blob_len < (u64)sess_key_off + sess_key_len) + return -EINVAL; + + ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL); + if (!ctx_arc4) + return -ENOMEM; + + cifs_arc4_setkey(ctx_arc4, sess->sess_key, + SMB2_NTLMV2_SESSKEY_SIZE); + cifs_arc4_crypt(ctx_arc4, sess->sess_key, + (char *)authblob + sess_key_off, sess_key_len); + kfree_sensitive(ctx_arc4); + } + return ret; } @@ -414,6 +438,9 @@ ksmbd_build_ntlmssp_challenge_blob(struc (cflags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) flags |= NTLMSSP_NEGOTIATE_EXTENDED_SEC; + if (cflags & NTLMSSP_NEGOTIATE_KEY_XCH) + flags |= NTLMSSP_NEGOTIATE_KEY_XCH; + chgblob->NegotiateFlags = cpu_to_le32(flags); len = strlen(ksmbd_netbios_name()); name = kmalloc(2 + UNICODE_LEN(len), GFP_KERNEL);