From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932697AbcFIVpQ (ORCPT ); Thu, 9 Jun 2016 17:45:16 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:51179 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752372AbcFIVTR (ORCPT ); Thu, 9 Jun 2016 17:19:17 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Stefan Metzmacher , Steve French , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 113/206] fs/cifs: correctly to anonymous authentication via NTLMSSP Date: Thu, 9 Jun 2016 14:15:22 -0700 Message-Id: <1465507015-23052-114-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1465507015-23052-1-git-send-email-kamal@canonical.com> References: <1465507015-23052-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt12 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Stefan Metzmacher commit cfda35d98298131bf38fbad3ce4cd5ecb3cf18db upstream. See [MS-NLMP] 3.2.5.1.2 Server Receives an AUTHENTICATE_MESSAGE from the Client: ... Set NullSession to FALSE If (AUTHENTICATE_MESSAGE.UserNameLen == 0 AND AUTHENTICATE_MESSAGE.NtChallengeResponse.Length == 0 AND (AUTHENTICATE_MESSAGE.LmChallengeResponse == Z(1) OR AUTHENTICATE_MESSAGE.LmChallengeResponse.Length == 0)) -- Special case: client requested anonymous authentication Set NullSession to TRUE ... Only server which map unknown users to guest will allow access using a non-null NTChallengeResponse. For Samba it's the "map to guest = bad user" option. BUG: https://bugzilla.samba.org/show_bug.cgi?id=11913 Signed-off-by: Stefan Metzmacher Signed-off-by: Steve French Signed-off-by: Kamal Mostafa --- fs/cifs/sess.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index bce6fdc..abaeeab 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -400,19 +400,27 @@ int build_ntlmssp_auth_blob(unsigned char *pbuffer, sec_blob->LmChallengeResponse.MaximumLength = 0; sec_blob->NtChallengeResponse.BufferOffset = cpu_to_le32(tmp - pbuffer); - rc = setup_ntlmv2_rsp(ses, nls_cp); - if (rc) { - cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc); - goto setup_ntlmv2_ret; + if (ses->user_name != NULL) { + rc = setup_ntlmv2_rsp(ses, nls_cp); + if (rc) { + cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc); + goto setup_ntlmv2_ret; + } + memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE, + ses->auth_key.len - CIFS_SESS_KEY_SIZE); + tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE; + + sec_blob->NtChallengeResponse.Length = + cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE); + sec_blob->NtChallengeResponse.MaximumLength = + cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE); + } else { + /* + * don't send an NT Response for anonymous access + */ + sec_blob->NtChallengeResponse.Length = 0; + sec_blob->NtChallengeResponse.MaximumLength = 0; } - memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE, - ses->auth_key.len - CIFS_SESS_KEY_SIZE); - tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE; - - sec_blob->NtChallengeResponse.Length = - cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE); - sec_blob->NtChallengeResponse.MaximumLength = - cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE); if (ses->domainName == NULL) { sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer); -- 2.7.4