1 files changed, 19 insertions, 7 deletions

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index b2934683bd08..d998c4f7aae5 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -404,7 +404,7 @@ static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
         /* In particular we can examine sign flags */
         /* BB spec says that if AvId field of MsvAvTimestamp is populated then
                 we must set the MIC field of the AUTHENTICATE_MESSAGE */
-
+        ses->ntlmssp.server_flags = le32_to_cpu(pblob->NegotiateFlags);
         tioffset = cpu_to_le16(pblob->TargetInfoArray.BufferOffset);
         tilen = cpu_to_le16(pblob->TargetInfoArray.Length);
         ses->tilen = tilen;
@@ -440,10 +440,12 @@ static void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
                 NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
                 NTLMSSP_NEGOTIATE_NTLM;
         if (ses->server->secMode &
-           (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
+                        (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
                 flags |= NTLMSSP_NEGOTIATE_SIGN;
-        if (ses->server->secMode & SECMODE_SIGN_REQUIRED)
-                flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
+                if (!ses->server->session_estab)
+                        flags |= NTLMSSP_NEGOTIATE_KEY_XCH |
+                                NTLMSSP_NEGOTIATE_EXTENDED_SEC;
+        }
 
         sec_blob->NegotiateFlags |= cpu_to_le32(flags);
 
@@ -543,9 +545,19 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
         sec_blob->WorkstationName.MaximumLength = 0;
         tmp += 2;
 
-        sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
-        sec_blob->SessionKey.Length = 0;
-        sec_blob->SessionKey.MaximumLength = 0;
+        if ((ses->ntlmssp.server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
+                        !calc_seckey(ses)) {
+                memcpy(tmp, ses->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE);
+                sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
+                sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
+                sec_blob->SessionKey.MaximumLength =
+                                cpu_to_le16(CIFS_CPHTXT_SIZE);
+                tmp += CIFS_CPHTXT_SIZE;
+        } else {
+                sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
+                sec_blob->SessionKey.Length = 0;
+                sec_blob->SessionKey.MaximumLength = 0;
+        }
 
 setup_ntlmv2_ret:
         *buflen = tmp - pbuffer;