[PATCH 4.4 04/97] CIFS: Enable encryption during session setup phase

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Pavel Shilovsky <pshi...@microsoft.com>

commit cabfb3680f78981d26c078a26e5c748531257ebb upstream.

In order to allow encryption on SMB connection we need to exchange
a session key and generate encryption and decryption keys.

Signed-off-by: Pavel Shilovsky <pshi...@microsoft.com>
Signed-off-by: Srivatsa S. Bhat <sriva...@csail.mit.edu>
Cc: Steve French <smfre...@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 fs/cifs/sess.c    |   22 ++++++++++------------
 fs/cifs/smb2pdu.c |    8 +-------
 2 files changed, 11 insertions(+), 19 deletions(-)

--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -344,13 +344,12 @@ void build_ntlmssp_negotiate_blob(unsign
        /* BB is NTLMV2 session security format easier to use here? */
        flags = NTLMSSP_NEGOTIATE_56 |  NTLMSSP_REQUEST_TARGET |
                NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
-               NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
-       if (ses->server->sign) {
+               NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
+               NTLMSSP_NEGOTIATE_SEAL;
+       if (ses->server->sign)
                flags |= NTLMSSP_NEGOTIATE_SIGN;
-               if (!ses->server->session_estab ||
-                               ses->ntlmssp->sesskey_per_smbsess)
-                       flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
-       }
+       if (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
+               flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
 
        sec_blob->NegotiateFlags = cpu_to_le32(flags);
 
@@ -407,13 +406,12 @@ int build_ntlmssp_auth_blob(unsigned cha
        flags = NTLMSSP_NEGOTIATE_56 |
                NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
                NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
-               NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
-       if (ses->server->sign) {
+               NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
+               NTLMSSP_NEGOTIATE_SEAL;
+       if (ses->server->sign)
                flags |= NTLMSSP_NEGOTIATE_SIGN;
-               if (!ses->server->session_estab ||
-                               ses->ntlmssp->sesskey_per_smbsess)
-                       flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
-       }
+       if (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
+               flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
 
        tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
        sec_blob->NegotiateFlags = cpu_to_le32(flags);
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -832,10 +832,8 @@ ssetup_exit:
 
        if (!rc) {
                mutex_lock(&server->srv_mutex);
-               if (server->sign && server->ops->generate_signingkey) {
+               if (server->ops->generate_signingkey) {
                        rc = server->ops->generate_signingkey(ses);
-                       kfree(ses->auth_key.response);
-                       ses->auth_key.response = NULL;
                        if (rc) {
                                cifs_dbg(FYI,
                                        "SMB3 session key generation failed\n");
@@ -857,10 +855,6 @@ ssetup_exit:
        }
 
 keygen_exit:
-       if (!server->sign) {
-               kfree(ses->auth_key.response);
-               ses->auth_key.response = NULL;
-       }
        if (spnego_key) {
                key_invalidate(spnego_key);
                key_put(spnego_key);