diff options
| author | Stefan Metzmacher <metze@samba.org> | 2016-05-03 10:52:30 +0200 |
|---|---|---|
| committer | Steve French <smfrench@gmail.com> | 2016-05-17 14:09:33 -0500 |
| commit | cfda35d98298131bf38fbad3ce4cd5ecb3cf18db (patch) | |
| tree | 02e8c5bfae387525a063ebae2d51e7745862f21d /fs/cifs/sess.c | |
| parent | 11e31647c9263185cfd990db656dbb7f06697faf (diff) | |
| download | lwn-cfda35d98298131bf38fbad3ce4cd5ecb3cf18db.tar.gz lwn-cfda35d98298131bf38fbad3ce4cd5ecb3cf18db.zip | |
fs/cifs: correctly to anonymous authentication via NTLMSSP
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
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Diffstat (limited to 'fs/cifs/sess.c')
| -rw-r--r-- | fs/cifs/sess.c | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index 59727e32ed0f..09b0201d15d0 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); |