From 5c234aa5e33ed9037354a4c94d0d3e0350abe5eb Mon Sep 17 00:00:00 2001 From: Shirish Pargaonkar Date: Thu, 29 Aug 2013 08:35:10 -0500 Subject: [PATCH] cifs: Add a variable specific to NTLMSSP for key exchange. Add a variable specific to NTLMSSP authentication to determine whether to exchange keys during negotiation and authentication phases. Since session key for smb1 is per smb connection, once a very first sesion is established, there is no need for key exchange during subsequent session setups. As a result, smb1 session setup code sets this variable as false. Since session key for smb2 and smb3 is per smb connection, we need to exchange keys to generate session key for every sesion being established. As a result, smb2/3 session setup code sets this variable as true. Acked-by: Jeff Layton Signed-off-by: Shirish Pargaonkar Signed-off-by: Steve French --- fs/cifs/cifsglob.h | 1 + fs/cifs/sess.c | 8 ++++++-- fs/cifs/smb2pdu.c | 1 + 3 files changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index fb186f7bae49..20c7f8f4fba8 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -131,6 +131,7 @@ struct cifs_secmech { /* per smb session structure/fields */ struct ntlmssp_auth { + bool sesskey_per_smbsess; /* whether session key is per smb session */ __u32 client_flags; /* sent by client in type 1 ntlmsssp exchange */ __u32 server_flags; /* sent by server in type 2 ntlmssp exchange */ unsigned char ciphertext[CIFS_CPHTXT_SIZE]; /* sent to server */ diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index acea6c4ded47..5f99b7f19e78 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -428,7 +428,8 @@ void build_ntlmssp_negotiate_blob(unsigned char *pbuffer, NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC; if (ses->server->sign) { flags |= NTLMSSP_NEGOTIATE_SIGN; - if (!ses->server->session_estab) + if (!ses->server->session_estab || + ses->ntlmssp->sesskey_per_smbsess) flags |= NTLMSSP_NEGOTIATE_KEY_XCH; } @@ -466,7 +467,8 @@ int build_ntlmssp_auth_blob(unsigned char *pbuffer, NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC; if (ses->server->sign) { flags |= NTLMSSP_NEGOTIATE_SIGN; - if (!ses->server->session_estab) + if (!ses->server->session_estab || + ses->ntlmssp->sesskey_per_smbsess) flags |= NTLMSSP_NEGOTIATE_KEY_XCH; } @@ -641,6 +643,8 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses, ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL); if (!ses->ntlmssp) return -ENOMEM; + ses->ntlmssp->sesskey_per_smbsess = false; + } ssetup_ntlmssp_authenticate: diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index f56cf99e027a..3d010766f267 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -491,6 +491,7 @@ SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses, ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL); if (!ses->ntlmssp) return -ENOMEM; + ses->ntlmssp->sesskey_per_smbsess = true; /* FIXME: allow for other auth types besides NTLMSSP (e.g. krb5) */ ses->sectype = RawNTLMSSP;