[PATCH 0/5 v4] Split CIFS_SessSetup()

[PATCH 0/5 v4] Split CIFS_SessSetup()

[Sachin Prabhu]

I am investigating the possibility of adding support for gss-proxy in the
cifs client module. As part of that investigation, I was looking at the
CIFS_SessSetup() function. This is a long function which handles multiple auths
using if conditions and switch statements. The code struction makes it
difficult to modify or add support for new authentication mechanisms.

The proposal is to split the various authentication code into its own separate
functions. This increases the lines of code but will simplify maintenance and
addition of new auth methods.

The short term goal is to add gss-proxy support for kerberos authentication.
This will require to and fro communication with the gss-proxy module over a
unix socket.

Further long term goals are 
1) Add support for NTLMSSP using SPNEGO,
2) Allow clients to negotiate which authentication mechanism to use using SPNEGO.

V2:
- Ensure that sess_data allocated on intermediate patches are freed.
- Remove ifdef-endif blocks from the switch statement in CIFS_SessSetup().

V3:
- Fix whitespace errors in some patches.
- Change sess_establish_session to return errors. Call this function only in
  case of successful establish session calls to the server.
- Delete an incorrect comment in case of rawntlmssp authentication.
- Delete an if statement before kfree(ntlmssp) in rawntlmssp authentication.

v4:
- reordered elements of struct sess_data as asked by jlayton
- Use free_rsp_buf() to clean buffer.
- Clean up the rawntlmssp case further and break the calls into separate
  functions.

Sachin Prabhu (5):
  cifs: replace code with free_rsp_buf()
  cifs: Split lanman auth from CIFS_SessSetup()
  cifs: Split ntlm and ntlmv2 authentication methods off
    CIFS_SessSetup()
  cifs: Split Kerberos authentication off CIFS_SessSetup()
  cifs: Separate rawntlmssp auth from CIFS_SessSetup()

 fs/cifs/cifsproto.h |    1 +
 fs/cifs/cifssmb.c   |   20 +-
 fs/cifs/misc.c      |    9 +
 fs/cifs/sess.c      | 1192 ++++++++++++++++++++++++++++++++++++---------------
 fs/cifs/smb2pdu.c   |   10 -
 5 files changed, 854 insertions(+), 378 deletions(-)

-- 
1.9.3

[PATCH 1/5] cifs: replace code with free_rsp_buf()

[Sachin Prabhu]

The functionality provided by free_rsp_buf() is duplicated in a number
of places. Replace these instances with a call to free_rsp_buf().

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/cifsproto.h |  1 +
 fs/cifs/cifssmb.c   | 20 ++++----------------
 fs/cifs/misc.c      |  9 +++++++++
 fs/cifs/smb2pdu.c   | 10 ----------
 4 files changed, 14 insertions(+), 26 deletions(-)

diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index ca7980a..de49d7a 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -36,6 +36,7 @@ extern struct smb_hdr *cifs_buf_get(void);
 extern void cifs_buf_release(void *);
 extern struct smb_hdr *cifs_small_buf_get(void);
 extern void cifs_small_buf_release(void *);
+extern void free_rsp_buf(int, void *);
 extern void cifs_rqst_page_to_kvec(struct smb_rqst *rqst, unsigned int idx,
 					struct kvec *iov);
 extern int smb_send(struct TCP_Server_Info *, struct smb_hdr *,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 6ce4e09..b7e5b65 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1734,10 +1734,7 @@ CIFSSMBRead(const unsigned int xid, struct cifs_io_parms *io_parms,
 
 /*	cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
 	if (*buf) {
-		if (resp_buf_type == CIFS_SMALL_BUFFER)
-			cifs_small_buf_release(iov[0].iov_base);
-		else if (resp_buf_type == CIFS_LARGE_BUFFER)
-			cifs_buf_release(iov[0].iov_base);
+		free_rsp_buf(resp_buf_type, iov[0].iov_base);
 	} else if (resp_buf_type != CIFS_NO_BUFFER) {
 		/* return buffer to caller to free */
 		*buf = iov[0].iov_base;
@@ -2203,10 +2200,7 @@ CIFSSMBWrite2(const unsigned int xid, struct cifs_io_parms *io_parms,
 	}
 
 /*	cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
-	if (resp_buf_type == CIFS_SMALL_BUFFER)
-		cifs_small_buf_release(iov[0].iov_base);
-	else if (resp_buf_type == CIFS_LARGE_BUFFER)
-		cifs_buf_release(iov[0].iov_base);
+	free_rsp_buf(resp_buf_type, iov[0].iov_base);
 
 	/* Note: On -EAGAIN error only caller can retry on handle based calls
 		since file handle passed in no longer valid */
@@ -2451,10 +2445,7 @@ plk_err_exit:
 	if (pSMB)
 		cifs_small_buf_release(pSMB);
 
-	if (resp_buf_type == CIFS_SMALL_BUFFER)
-		cifs_small_buf_release(iov[0].iov_base);
-	else if (resp_buf_type == CIFS_LARGE_BUFFER)
-		cifs_buf_release(iov[0].iov_base);
+	free_rsp_buf(resp_buf_type, iov[0].iov_base);
 
 	/* Note: On -EAGAIN error only caller can retry on handle based calls
 	   since file handle passed in no longer valid */
@@ -3838,10 +3829,7 @@ CIFSSMBGetCIFSACL(const unsigned int xid, struct cifs_tcon *tcon, __u16 fid,
 		}
 	}
 qsec_out:
-	if (buf_type == CIFS_SMALL_BUFFER)
-		cifs_small_buf_release(iov[0].iov_base);
-	else if (buf_type == CIFS_LARGE_BUFFER)
-		cifs_buf_release(iov[0].iov_base);
+	free_rsp_buf(buf_type, iov[0].iov_base);
 /*	cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
 	return rc;
 }
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 3b0c62e..64997a0 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -226,6 +226,15 @@ cifs_small_buf_release(void *buf_to_free)
 	return;
 }
 
+void
+free_rsp_buf(int resp_buftype, void *rsp)
+{
+	if (resp_buftype == CIFS_SMALL_BUFFER)
+		cifs_small_buf_release(rsp);
+	else if (resp_buftype == CIFS_LARGE_BUFFER)
+		cifs_buf_release(rsp);
+}
+
 /* NB: MID can not be set if treeCon not passed in, in that
    case it is responsbility of caller to set the mid */
 void
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index b0b260d..0158104 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -309,16 +309,6 @@ small_smb2_init(__le16 smb2_command, struct cifs_tcon *tcon,
 	return rc;
 }
 
-static void
-free_rsp_buf(int resp_buftype, void *rsp)
-{
-	if (resp_buftype == CIFS_SMALL_BUFFER)
-		cifs_small_buf_release(rsp);
-	else if (resp_buftype == CIFS_LARGE_BUFFER)
-		cifs_buf_release(rsp);
-}
-
-
 /*
  *
  *	SMB2 Worker functions follow:
-- 
1.9.3

[PATCH 2/5] cifs: Split lanman auth from CIFS_SessSetup()

[Sachin Prabhu]

In preparation for splitting CIFS_SessSetup() into smaller more
manageable chunks, we first add helper functions.

We then proceed to split out lanman auth out of CIFS_SessSetup()

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/sess.c | 303 ++++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 258 insertions(+), 45 deletions(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index e87387d..36d0b90 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -520,6 +520,240 @@ select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
 	}
 }
 
+struct sess_data {
+	unsigned int xid;
+	struct cifs_ses *ses;
+	struct nls_table *nls_cp;
+	void (*func)(struct sess_data *);
+	int result;
+
+	/* we will send the SMB in three pieces:
+	 * a fixed length beginning part, an optional
+	 * SPNEGO blob (which can be zero length), and a
+	 * last part which will include the strings
+	 * and rest of bcc area. This allows us to avoid
+	 * a large buffer 17K allocation
+	 */
+	int buf0_type;
+	struct kvec iov[3];
+};
+
+static int
+sess_alloc_buffer(struct sess_data *sess_data, int wct)
+{
+	int rc;
+	struct cifs_ses *ses = sess_data->ses;
+	struct smb_hdr *smb_buf;
+
+	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
+				  (void **)&smb_buf);
+
+	if (rc)
+		return rc;
+
+	sess_data->iov[0].iov_base = (char *)smb_buf;
+	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
+	/*
+	 * This variable will be used to clear the buffer
+	 * allocated above in case of any error in the calling function.
+	 */
+	sess_data->buf0_type = CIFS_SMALL_BUFFER;
+
+	/* 2000 big enough to fit max user, domain, NOS name etc. */
+	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
+	if (!sess_data->iov[2].iov_base) {
+		rc = -ENOMEM;
+		goto out_free_smb_buf;
+	}
+
+	return 0;
+
+out_free_smb_buf:
+	kfree(smb_buf);
+	sess_data->iov[0].iov_base = NULL;
+	sess_data->iov[0].iov_len = 0;
+	sess_data->buf0_type = CIFS_NO_BUFFER;
+	return rc;
+}
+
+static void
+sess_free_buffer(struct sess_data *sess_data)
+{
+
+	free_rsp_buf(sess_data->buf0_type, sess_data->iov[0].iov_base);
+	sess_data->buf0_type = CIFS_NO_BUFFER;
+	kfree(sess_data->iov[2].iov_base);
+}
+
+static int
+sess_establish_session(struct sess_data *sess_data)
+{
+	struct cifs_ses *ses = sess_data->ses;
+
+	mutex_lock(&ses->server->srv_mutex);
+	if (!ses->server->session_estab) {
+		if (ses->server->sign) {
+			ses->server->session_key.response =
+				kmemdup(ses->auth_key.response,
+				ses->auth_key.len, GFP_KERNEL);
+			if (!ses->server->session_key.response) {
+				mutex_unlock(&ses->server->srv_mutex);
+				return -ENOMEM;
+			}
+			ses->server->session_key.len =
+						ses->auth_key.len;
+		}
+		ses->server->sequence_number = 0x2;
+		ses->server->session_estab = true;
+	}
+	mutex_unlock(&ses->server->srv_mutex);
+
+	cifs_dbg(FYI, "CIFS session established successfully\n");
+	spin_lock(&GlobalMid_Lock);
+	ses->status = CifsGood;
+	ses->need_reconnect = false;
+	spin_unlock(&GlobalMid_Lock);
+
+	return 0;
+}
+
+static int
+sess_sendreceive(struct sess_data *sess_data)
+{
+	int rc;
+	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
+	__u16 count;
+
+	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
+	smb_buf->smb_buf_length =
+		cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
+	put_bcc(count, smb_buf);
+
+	rc = SendReceive2(sess_data->xid, sess_data->ses,
+			  sess_data->iov, 3 /* num_iovecs */,
+			  &sess_data->buf0_type,
+			  CIFS_LOG_ERROR);
+
+	return rc;
+}
+
+/*
+ * LANMAN and plaintext are less secure and off by default.
+ * So we make this explicitly be turned on in kconfig (in the
+ * build) and turned on at runtime (changed from the default)
+ * in proc/fs/cifs or via mount parm.  Unfortunately this is
+ * needed for old Win (e.g. Win95), some obscure NAS and OS/2
+ */
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+static void
+sess_auth_lanman(struct sess_data *sess_data)
+{
+	int rc = 0;
+	struct smb_hdr *smb_buf;
+	SESSION_SETUP_ANDX *pSMB;
+	char *bcc_ptr;
+	struct cifs_ses *ses = sess_data->ses;
+	char lnm_session_key[CIFS_AUTH_RESP_SIZE];
+	__u32 capabilities;
+	__u16 bytes_remaining;
+
+	/* lanman 2 style sessionsetup */
+	/* wct = 10 */
+	rc = sess_alloc_buffer(sess_data, 10);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	bcc_ptr = sess_data->iov[2].iov_base;
+	capabilities = cifs_ssetup_hdr(ses, pSMB);
+
+	pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
+
+	/* no capabilities flags in old lanman negotiation */
+	pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
+
+	/* Calculate hash with password and copy into bcc_ptr.
+	 * Encryption Key (stored as in cryptkey) gets used if the
+	 * security mode bit in Negottiate Protocol response states
+	 * to use challenge/response method (i.e. Password bit is 1).
+	 */
+	rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
+			      ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
+			      true : false, lnm_session_key);
+
+	memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
+	bcc_ptr += CIFS_AUTH_RESP_SIZE;
+
+	/*
+	 * can not sign if LANMAN negotiated so no need
+	 * to calculate signing key? but what if server
+	 * changed to do higher than lanman dialect and
+	 * we reconnected would we ever calc signing_key?
+	 */
+
+	cifs_dbg(FYI, "Negotiating LANMAN setting up strings\n");
+	/* Unicode not allowed for LANMAN dialects */
+	ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
+
+	sess_data->iov[2].iov_len = (long) bcc_ptr -
+			(long) sess_data->iov[2].iov_base;
+
+	rc = sess_sendreceive(sess_data);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
+
+	/* lanman response has a word count of 3 */
+	if (smb_buf->WordCount != 3) {
+		rc = -EIO;
+		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
+		goto out;
+	}
+
+	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
+		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
+
+	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
+	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
+
+	bytes_remaining = get_bcc(smb_buf);
+	bcc_ptr = pByteArea(smb_buf);
+
+	/* BB check if Unicode and decode strings */
+	if (bytes_remaining == 0) {
+		/* no string area to decode, do nothing */
+	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
+		/* unicode string area must be word-aligned */
+		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+			++bcc_ptr;
+			--bytes_remaining;
+		}
+		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
+				      sess_data->nls_cp);
+	} else {
+		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
+				    sess_data->nls_cp);
+	}
+
+	rc = sess_establish_session(sess_data);
+out:
+	sess_data->result = rc;
+	sess_data->func = NULL;
+	sess_free_buffer(sess_data);
+}
+
+#else
+
+static void
+sess_auth_lanman(struct sess_data *sess_data)
+{
+	sess_data->result = -EOPNOTSUPP;
+	sess_data->func = NULL;
+}
+#endif
+
 int
 CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	       const struct nls_table *nls_cp)
@@ -540,12 +774,21 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
 	u16 blob_len;
 	char *ntlmsspblob = NULL;
+	struct sess_data *sess_data;
 
 	if (ses == NULL) {
 		WARN(1, "%s: ses == NULL!", __func__);
 		return -EINVAL;
 	}
 
+	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
+	if (!sess_data)
+		return -ENOMEM;
+	sess_data->xid = xid;
+	sess_data->ses = ses;
+	sess_data->buf0_type = CIFS_NO_BUFFER;
+	sess_data->nls_cp = (struct nls_table *) nls_cp;
+
 	type = select_sectype(ses->server, ses->sectype);
 	cifs_dbg(FYI, "sess setup type %d\n", type);
 	if (type == Unspecified) {
@@ -554,6 +797,14 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 		return -EINVAL;
 	}
 
+	switch (type) {
+	case LANMAN:
+		sess_auth_lanman(sess_data);
+		goto out;
+	default:
+		cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
+	}
+
 	if (type == RawNTLMSSP) {
 		/* if memory allocation is successful, caller of this function
 		 * frees it.
@@ -569,17 +820,7 @@ ssetup_ntlmssp_authenticate:
 	if (phase == NtLmChallenge)
 		phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
 
-	if (type == LANMAN) {
-#ifndef CONFIG_CIFS_WEAK_PW_HASH
-		/* LANMAN and plaintext are less secure and off by default.
-		So we make this explicitly be turned on in kconfig (in the
-		build) and turned on at runtime (changed from the default)
-		in proc/fs/cifs or via mount parm.  Unfortunately this is
-		needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
-		return -EOPNOTSUPP;
-#endif
-		wct = 10; /* lanman 2 style sessionsetup */
-	} else if ((type == NTLM) || (type == NTLMv2)) {
+	if ((type == NTLM) || (type == NTLMv2)) {
 		/* For NTLMv2 failures eventually may need to retry NTLM */
 		wct = 13; /* old style NTLM sessionsetup */
 	} else /* same size: negotiate or auth, NTLMSSP or extended security */
@@ -618,39 +859,7 @@ ssetup_ntlmssp_authenticate:
 	iov[1].iov_base = NULL;
 	iov[1].iov_len = 0;
 
-	if (type == LANMAN) {
-#ifdef CONFIG_CIFS_WEAK_PW_HASH
-		char lnm_session_key[CIFS_AUTH_RESP_SIZE];
-
-		pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
-
-		/* no capabilities flags in old lanman negotiation */
-
-		pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-
-		/* Calculate hash with password and copy into bcc_ptr.
-		 * Encryption Key (stored as in cryptkey) gets used if the
-		 * security mode bit in Negottiate Protocol response states
-		 * to use challenge/response method (i.e. Password bit is 1).
-		 */
-
-		rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
-				 ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
-					true : false, lnm_session_key);
-
-		memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-
-		/* can not sign if LANMAN negotiated so no need
-		to calculate signing key? but what if server
-		changed to do higher than lanman dialect and
-		we reconnected would we ever calc signing_key? */
-
-		cifs_dbg(FYI, "Negotiating LANMAN setting up strings\n");
-		/* Unicode not allowed for LANMAN dialects */
-		ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
-#endif
-	} else if (type == NTLM) {
+	if (type == NTLM) {
 		pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 		pSMB->req_no_secext.CaseInsensitivePasswordLength =
 			cpu_to_le16(CIFS_AUTH_RESP_SIZE);
@@ -889,7 +1098,6 @@ ssetup_ntlmssp_authenticate:
 		}
 		if (phase == NtLmChallenge) {
 			rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
-			/* now goto beginning for ntlmssp authenticate phase */
 			if (rc)
 				goto ssetup_exit;
 		}
@@ -962,4 +1170,9 @@ keycp_exit:
 	kfree(ses->ntlmssp);
 
 	return rc;
+
+out:
+	rc = sess_data->result;
+	kfree(sess_data);
+	return rc;
 }
-- 
1.9.3

[PATCH 3/5] cifs: Split ntlm and ntlmv2 authentication methods off CIFS_SessSetup()

[Sachin Prabhu]

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/sess.c | 316 ++++++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 232 insertions(+), 84 deletions(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 36d0b90..4f481c1 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -754,6 +754,216 @@ sess_auth_lanman(struct sess_data *sess_data)
 }
 #endif
 
+static void
+sess_auth_ntlm(struct sess_data *sess_data)
+{
+	int rc = 0;
+	struct smb_hdr *smb_buf;
+	SESSION_SETUP_ANDX *pSMB;
+	char *bcc_ptr;
+	struct cifs_ses *ses = sess_data->ses;
+	__u32 capabilities;
+	__u16 bytes_remaining;
+
+	/* old style NTLM sessionsetup */
+	/* wct = 13 */
+	rc = sess_alloc_buffer(sess_data, 13);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	bcc_ptr = sess_data->iov[2].iov_base;
+	capabilities = cifs_ssetup_hdr(ses, pSMB);
+
+	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
+	pSMB->req_no_secext.CaseInsensitivePasswordLength =
+			cpu_to_le16(CIFS_AUTH_RESP_SIZE);
+	pSMB->req_no_secext.CaseSensitivePasswordLength =
+			cpu_to_le16(CIFS_AUTH_RESP_SIZE);
+
+	/* calculate ntlm response and session key */
+	rc = setup_ntlm_response(ses, sess_data->nls_cp);
+	if (rc) {
+		cifs_dbg(VFS, "Error %d during NTLM authentication\n",
+				 rc);
+		goto out;
+	}
+
+	/* copy ntlm response */
+	memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
+			CIFS_AUTH_RESP_SIZE);
+	bcc_ptr += CIFS_AUTH_RESP_SIZE;
+	memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
+			CIFS_AUTH_RESP_SIZE);
+	bcc_ptr += CIFS_AUTH_RESP_SIZE;
+
+	if (ses->capabilities & CAP_UNICODE) {
+		/* unicode strings must be word aligned */
+		if (sess_data->iov[0].iov_len % 2) {
+			*bcc_ptr = 0;
+			bcc_ptr++;
+		}
+		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
+	} else {
+		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
+	}
+
+
+	sess_data->iov[2].iov_len = (long) bcc_ptr -
+			(long) sess_data->iov[2].iov_base;
+
+	rc = sess_sendreceive(sess_data);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
+
+	if (smb_buf->WordCount != 3) {
+		rc = -EIO;
+		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
+		goto out;
+	}
+
+	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
+		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
+
+	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
+	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
+
+	bytes_remaining = get_bcc(smb_buf);
+	bcc_ptr = pByteArea(smb_buf);
+
+	/* BB check if Unicode and decode strings */
+	if (bytes_remaining == 0) {
+		/* no string area to decode, do nothing */
+	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
+		/* unicode string area must be word-aligned */
+		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+			++bcc_ptr;
+			--bytes_remaining;
+		}
+		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
+				      sess_data->nls_cp);
+	} else {
+		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
+				    sess_data->nls_cp);
+	}
+
+	rc = sess_establish_session(sess_data);
+out:
+	sess_data->result = rc;
+	sess_data->func = NULL;
+	sess_free_buffer(sess_data);
+	kfree(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+}
+
+static void
+sess_auth_ntlmv2(struct sess_data *sess_data)
+{
+	int rc = 0;
+	struct smb_hdr *smb_buf;
+	SESSION_SETUP_ANDX *pSMB;
+	char *bcc_ptr;
+	struct cifs_ses *ses = sess_data->ses;
+	__u32 capabilities;
+	__u16 bytes_remaining;
+
+	/* old style NTLM sessionsetup */
+	/* wct = 13 */
+	rc = sess_alloc_buffer(sess_data, 13);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	bcc_ptr = sess_data->iov[2].iov_base;
+	capabilities = cifs_ssetup_hdr(ses, pSMB);
+
+	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
+
+	/* LM2 password would be here if we supported it */
+	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
+
+	/* calculate nlmv2 response and session key */
+	rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
+	if (rc) {
+		cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
+		goto out;
+	}
+
+	memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
+			ses->auth_key.len - CIFS_SESS_KEY_SIZE);
+	bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
+
+	/* set case sensitive password length after tilen may get
+	 * assigned, tilen is 0 otherwise.
+	 */
+	pSMB->req_no_secext.CaseSensitivePasswordLength =
+		cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
+
+	if (ses->capabilities & CAP_UNICODE) {
+		if (sess_data->iov[0].iov_len % 2) {
+			*bcc_ptr = 0;
+			bcc_ptr++;
+		}
+		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
+	} else {
+		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
+	}
+
+
+	sess_data->iov[2].iov_len = (long) bcc_ptr -
+			(long) sess_data->iov[2].iov_base;
+
+	rc = sess_sendreceive(sess_data);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
+
+	if (smb_buf->WordCount != 3) {
+		rc = -EIO;
+		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
+		goto out;
+	}
+
+	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
+		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
+
+	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
+	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
+
+	bytes_remaining = get_bcc(smb_buf);
+	bcc_ptr = pByteArea(smb_buf);
+
+	/* BB check if Unicode and decode strings */
+	if (bytes_remaining == 0) {
+		/* no string area to decode, do nothing */
+	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
+		/* unicode string area must be word-aligned */
+		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+			++bcc_ptr;
+			--bytes_remaining;
+		}
+		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
+				      sess_data->nls_cp);
+	} else {
+		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
+				    sess_data->nls_cp);
+	}
+
+	rc = sess_establish_session(sess_data);
+out:
+	sess_data->result = rc;
+	sess_data->func = NULL;
+	sess_free_buffer(sess_data);
+	kfree(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+}
+
+
 int
 CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	       const struct nls_table *nls_cp)
@@ -801,6 +1011,12 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	case LANMAN:
 		sess_auth_lanman(sess_data);
 		goto out;
+	case NTLM:
+		sess_auth_ntlm(sess_data);
+		goto out;
+	case NTLMv2:
+		sess_auth_ntlmv2(sess_data);
+		goto out;
 	default:
 		cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
 	}
@@ -820,11 +1036,8 @@ ssetup_ntlmssp_authenticate:
 	if (phase == NtLmChallenge)
 		phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
 
-	if ((type == NTLM) || (type == NTLMv2)) {
-		/* For NTLMv2 failures eventually may need to retry NTLM */
-		wct = 13; /* old style NTLM sessionsetup */
-	} else /* same size: negotiate or auth, NTLMSSP or extended security */
-		wct = 12;
+	/* same size: negotiate or auth, NTLMSSP or extended security */
+	wct = 12;
 
 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
 			    (void **)&smb_buf);
@@ -859,70 +1072,7 @@ ssetup_ntlmssp_authenticate:
 	iov[1].iov_base = NULL;
 	iov[1].iov_len = 0;
 
-	if (type == NTLM) {
-		pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
-		pSMB->req_no_secext.CaseInsensitivePasswordLength =
-			cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-		pSMB->req_no_secext.CaseSensitivePasswordLength =
-			cpu_to_le16(CIFS_AUTH_RESP_SIZE);
-
-		/* calculate ntlm response and session key */
-		rc = setup_ntlm_response(ses, nls_cp);
-		if (rc) {
-			cifs_dbg(VFS, "Error %d during NTLM authentication\n",
-				 rc);
-			goto ssetup_exit;
-		}
-
-		/* copy ntlm response */
-		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
-				CIFS_AUTH_RESP_SIZE);
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
-				CIFS_AUTH_RESP_SIZE);
-		bcc_ptr += CIFS_AUTH_RESP_SIZE;
-
-		if (ses->capabilities & CAP_UNICODE) {
-			/* unicode strings must be word aligned */
-			if (iov[0].iov_len % 2) {
-				*bcc_ptr = 0;
-				bcc_ptr++;
-			}
-			unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
-		} else
-			ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
-	} else if (type == NTLMv2) {
-		pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
-
-		/* LM2 password would be here if we supported it */
-		pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
-
-		/* calculate nlmv2 response and session key */
-		rc = setup_ntlmv2_rsp(ses, nls_cp);
-		if (rc) {
-			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n",
-				 rc);
-			goto ssetup_exit;
-		}
-		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
-				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
-		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
-
-		/* set case sensitive password length after tilen may get
-		 * assigned, tilen is 0 otherwise.
-		 */
-		pSMB->req_no_secext.CaseSensitivePasswordLength =
-			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
-
-		if (ses->capabilities & CAP_UNICODE) {
-			if (iov[0].iov_len % 2) {
-				*bcc_ptr = 0;
-				bcc_ptr++;
-			}
-			unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
-		} else
-			ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
-	} else if (type == Kerberos) {
+	if (type == Kerberos) {
 #ifdef CONFIG_CIFS_UPCALL
 		struct cifs_spnego_msg *msg;
 
@@ -1073,7 +1223,7 @@ ssetup_ntlmssp_authenticate:
 	if (rc)
 		goto ssetup_exit;
 
-	if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
+	if (smb_buf->WordCount != 4) {
 		rc = -EIO;
 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
 		goto ssetup_exit;
@@ -1088,22 +1238,20 @@ ssetup_ntlmssp_authenticate:
 	bytes_remaining = get_bcc(smb_buf);
 	bcc_ptr = pByteArea(smb_buf);
 
-	if (smb_buf->WordCount == 4) {
-		blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
-		if (blob_len > bytes_remaining) {
-			cifs_dbg(VFS, "bad security blob length %d\n",
-				 blob_len);
-			rc = -EINVAL;
+	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
+	if (blob_len > bytes_remaining) {
+		cifs_dbg(VFS, "bad security blob length %d\n",
+			 blob_len);
+		rc = -EINVAL;
+		goto ssetup_exit;
+	}
+	if (phase == NtLmChallenge) {
+		rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
+		if (rc)
 			goto ssetup_exit;
-		}
-		if (phase == NtLmChallenge) {
-			rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
-			if (rc)
-				goto ssetup_exit;
-		}
-		bcc_ptr += blob_len;
-		bytes_remaining -= blob_len;
 	}
+	bcc_ptr += blob_len;
+	bytes_remaining -= blob_len;
 
 	/* BB check if Unicode and decode strings */
 	if (bytes_remaining == 0) {
-- 
1.9.3

[PATCH 4/5] cifs: Split Kerberos authentication off CIFS_SessSetup()

[Sachin Prabhu]

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/sess.c | 215 ++++++++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 153 insertions(+), 62 deletions(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 4f481c1..b413fae 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -963,6 +963,155 @@ out:
 	ses->auth_key.response = NULL;
 }
 
+#ifdef CONFIG_CIFS_UPCALL
+static void
+sess_auth_kerberos(struct sess_data *sess_data)
+{
+	int rc = 0;
+	struct smb_hdr *smb_buf;
+	SESSION_SETUP_ANDX *pSMB;
+	char *bcc_ptr;
+	struct cifs_ses *ses = sess_data->ses;
+	__u32 capabilities;
+	__u16 bytes_remaining;
+	struct key *spnego_key = NULL;
+	struct cifs_spnego_msg *msg;
+	u16 blob_len;
+
+	/* extended security */
+	/* wct = 12 */
+	rc = sess_alloc_buffer(sess_data, 12);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	bcc_ptr = sess_data->iov[2].iov_base;
+	capabilities = cifs_ssetup_hdr(ses, pSMB);
+
+	spnego_key = cifs_get_spnego_key(ses);
+	if (IS_ERR(spnego_key)) {
+		rc = PTR_ERR(spnego_key);
+		spnego_key = NULL;
+		goto out;
+	}
+
+	msg = spnego_key->payload.data;
+	/*
+	 * check version field to make sure that cifs.upcall is
+	 * sending us a response in an expected form
+	 */
+	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
+		cifs_dbg(VFS,
+		  "incorrect version of cifs.upcall (expected %d but got %d)",
+			      CIFS_SPNEGO_UPCALL_VERSION, msg->version);
+		rc = -EKEYREJECTED;
+		goto out_put_spnego_key;
+	}
+
+	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
+					 GFP_KERNEL);
+	if (!ses->auth_key.response) {
+		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory",
+				msg->sesskey_len);
+		rc = -ENOMEM;
+		goto out_put_spnego_key;
+	}
+	ses->auth_key.len = msg->sesskey_len;
+
+	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
+	capabilities |= CAP_EXTENDED_SECURITY;
+	pSMB->req.Capabilities = cpu_to_le32(capabilities);
+	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
+	sess_data->iov[1].iov_len = msg->secblob_len;
+	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
+
+	if (ses->capabilities & CAP_UNICODE) {
+		/* unicode strings must be word aligned */
+		if ((sess_data->iov[0].iov_len
+			+ sess_data->iov[1].iov_len) % 2) {
+			*bcc_ptr = 0;
+			bcc_ptr++;
+		}
+		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
+		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
+	} else {
+		/* BB: is this right? */
+		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
+	}
+
+	sess_data->iov[2].iov_len = (long) bcc_ptr -
+			(long) sess_data->iov[2].iov_base;
+
+	rc = sess_sendreceive(sess_data);
+	if (rc)
+		goto out_put_spnego_key;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
+
+	if (smb_buf->WordCount != 4) {
+		rc = -EIO;
+		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
+		goto out_put_spnego_key;
+	}
+
+	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
+		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
+
+	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
+	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
+
+	bytes_remaining = get_bcc(smb_buf);
+	bcc_ptr = pByteArea(smb_buf);
+
+	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
+	if (blob_len > bytes_remaining) {
+		cifs_dbg(VFS, "bad security blob length %d\n",
+				blob_len);
+		rc = -EINVAL;
+		goto out_put_spnego_key;
+	}
+	bcc_ptr += blob_len;
+	bytes_remaining -= blob_len;
+
+	/* BB check if Unicode and decode strings */
+	if (bytes_remaining == 0) {
+		/* no string area to decode, do nothing */
+	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
+		/* unicode string area must be word-aligned */
+		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+			++bcc_ptr;
+			--bytes_remaining;
+		}
+		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
+				      sess_data->nls_cp);
+	} else {
+		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
+				    sess_data->nls_cp);
+	}
+
+	rc = sess_establish_session(sess_data);
+out_put_spnego_key:
+	key_invalidate(spnego_key);
+	key_put(spnego_key);
+out:
+	sess_data->result = rc;
+	sess_data->func = NULL;
+	sess_free_buffer(sess_data);
+	kfree(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+}
+
+#else
+
+static void
+sess_auth_kerberos(struct sess_data *sess_data)
+{
+	cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
+	sess_data->result = -ENOSYS;
+	sess_data->func = NULL;
+}
+#endif /* ! CONFIG_CIFS_UPCALL */
 
 int
 CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
@@ -980,7 +1129,6 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	struct kvec iov[3];
 	enum securityEnum type;
 	__u16 action, bytes_remaining;
-	struct key *spnego_key = NULL;
 	__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
 	u16 blob_len;
 	char *ntlmsspblob = NULL;
@@ -1017,6 +1165,9 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	case NTLMv2:
 		sess_auth_ntlmv2(sess_data);
 		goto out;
+	case Kerberos:
+		sess_auth_kerberos(sess_data);
+		goto out;
 	default:
 		cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
 	}
@@ -1072,63 +1223,7 @@ ssetup_ntlmssp_authenticate:
 	iov[1].iov_base = NULL;
 	iov[1].iov_len = 0;
 
-	if (type == Kerberos) {
-#ifdef CONFIG_CIFS_UPCALL
-		struct cifs_spnego_msg *msg;
-
-		spnego_key = cifs_get_spnego_key(ses);
-		if (IS_ERR(spnego_key)) {
-			rc = PTR_ERR(spnego_key);
-			spnego_key = NULL;
-			goto ssetup_exit;
-		}
-
-		msg = spnego_key->payload.data;
-		/* check version field to make sure that cifs.upcall is
-		   sending us a response in an expected form */
-		if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
-			cifs_dbg(VFS, "incorrect version of cifs.upcall "
-				   "expected %d but got %d)",
-				   CIFS_SPNEGO_UPCALL_VERSION, msg->version);
-			rc = -EKEYREJECTED;
-			goto ssetup_exit;
-		}
-
-		ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
-						 GFP_KERNEL);
-		if (!ses->auth_key.response) {
-			cifs_dbg(VFS,
-				"Kerberos can't allocate (%u bytes) memory",
-				msg->sesskey_len);
-			rc = -ENOMEM;
-			goto ssetup_exit;
-		}
-		ses->auth_key.len = msg->sesskey_len;
-
-		pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
-		capabilities |= CAP_EXTENDED_SECURITY;
-		pSMB->req.Capabilities = cpu_to_le32(capabilities);
-		iov[1].iov_base = msg->data + msg->sesskey_len;
-		iov[1].iov_len = msg->secblob_len;
-		pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
-
-		if (ses->capabilities & CAP_UNICODE) {
-			/* unicode strings must be word aligned */
-			if ((iov[0].iov_len + iov[1].iov_len) % 2) {
-				*bcc_ptr = 0;
-				bcc_ptr++;
-			}
-			unicode_oslm_strings(&bcc_ptr, nls_cp);
-			unicode_domain_string(&bcc_ptr, ses, nls_cp);
-		} else
-		/* BB: is this right? */
-			ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
-#else /* ! CONFIG_CIFS_UPCALL */
-		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
-		rc = -ENOSYS;
-		goto ssetup_exit;
-#endif /* CONFIG_CIFS_UPCALL */
-	} else if (type == RawNTLMSSP) {
+	if (type == RawNTLMSSP) {
 		if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
 			cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
 			rc = -ENOSYS;
@@ -1268,10 +1363,6 @@ ssetup_ntlmssp_authenticate:
 	}
 
 ssetup_exit:
-	if (spnego_key) {
-		key_invalidate(spnego_key);
-		key_put(spnego_key);
-	}
 	kfree(str_area);
 	kfree(ntlmsspblob);
 	ntlmsspblob = NULL;
-- 
1.9.3

[PATCH 5/5] cifs: Separate rawntlmssp auth from CIFS_SessSetup()

[Sachin Prabhu]

Separate rawntlmssp authentication from CIFS_SessSetup(). Also cleanup
CIFS_SessSetup() since we no longer do any auth within it.

Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/sess.c | 490 +++++++++++++++++++++++++++++++--------------------------
 1 file changed, 263 insertions(+), 227 deletions(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index b413fae..c2e7c07 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -1113,241 +1113,225 @@ sess_auth_kerberos(struct sess_data *sess_data)
 }
 #endif /* ! CONFIG_CIFS_UPCALL */
 
-int
-CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
-	       const struct nls_table *nls_cp)
+/*
+ * The required kvec buffers have to be allocated before calling this
+ * function.
+ */
+static int
+_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
 {
-	int rc = 0;
-	int wct;
 	struct smb_hdr *smb_buf;
-	char *bcc_ptr;
-	char *str_area;
 	SESSION_SETUP_ANDX *pSMB;
+	struct cifs_ses *ses = sess_data->ses;
 	__u32 capabilities;
-	__u16 count;
-	int resp_buf_type;
-	struct kvec iov[3];
-	enum securityEnum type;
-	__u16 action, bytes_remaining;
-	__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
-	u16 blob_len;
-	char *ntlmsspblob = NULL;
-	struct sess_data *sess_data;
+	char *bcc_ptr;
 
-	if (ses == NULL) {
-		WARN(1, "%s: ses == NULL!", __func__);
-		return -EINVAL;
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)pSMB;
+
+	capabilities = cifs_ssetup_hdr(ses, pSMB);
+	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
+		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
+		return -ENOSYS;
 	}
 
-	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
-	if (!sess_data)
-		return -ENOMEM;
-	sess_data->xid = xid;
-	sess_data->ses = ses;
-	sess_data->buf0_type = CIFS_NO_BUFFER;
-	sess_data->nls_cp = (struct nls_table *) nls_cp;
+	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
+	capabilities |= CAP_EXTENDED_SECURITY;
+	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
 
-	type = select_sectype(ses->server, ses->sectype);
-	cifs_dbg(FYI, "sess setup type %d\n", type);
-	if (type == Unspecified) {
-		cifs_dbg(VFS,
-			"Unable to select appropriate authentication method!");
-		return -EINVAL;
+	bcc_ptr = sess_data->iov[2].iov_base;
+	/* unicode strings must be word aligned */
+	if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
+		*bcc_ptr = 0;
+		bcc_ptr++;
 	}
+	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
 
-	switch (type) {
-	case LANMAN:
-		sess_auth_lanman(sess_data);
-		goto out;
-	case NTLM:
-		sess_auth_ntlm(sess_data);
-		goto out;
-	case NTLMv2:
-		sess_auth_ntlmv2(sess_data);
-		goto out;
-	case Kerberos:
-		sess_auth_kerberos(sess_data);
-		goto out;
-	default:
-		cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
-	}
+	sess_data->iov[2].iov_len = (long) bcc_ptr -
+					(long) sess_data->iov[2].iov_base;
 
-	if (type == RawNTLMSSP) {
-		/* if memory allocation is successful, caller of this function
-		 * frees it.
-		 */
-		ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
-		if (!ses->ntlmssp)
-			return -ENOMEM;
-		ses->ntlmssp->sesskey_per_smbsess = false;
+	return 0;
+}
+
+static void
+sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
+
+static void
+sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
+{
+	int rc;
+	struct smb_hdr *smb_buf;
+	SESSION_SETUP_ANDX *pSMB;
+	struct cifs_ses *ses = sess_data->ses;
+	__u16 bytes_remaining;
+	char *bcc_ptr;
+	u16 blob_len;
+
+	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
 
+	/*
+	 * if memory allocation is successful, caller of this function
+	 * frees it.
+	 */
+	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
+	if (!ses->ntlmssp) {
+		rc = -ENOMEM;
+		goto out;
 	}
+	ses->ntlmssp->sesskey_per_smbsess = false;
 
-ssetup_ntlmssp_authenticate:
-	if (phase == NtLmChallenge)
-		phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
+	/* wct = 12 */
+	rc = sess_alloc_buffer(sess_data, 12);
+	if (rc)
+		goto out;
 
-	/* same size: negotiate or auth, NTLMSSP or extended security */
-	wct = 12;
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
 
-	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
-			    (void **)&smb_buf);
+	/* Build security blob before we assemble the request */
+	build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses);
+	sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
+	sess_data->iov[1].iov_base = pSMB->req.SecurityBlob;
+	pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
+
+	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
 	if (rc)
-		return rc;
+		goto out;
 
-	pSMB = (SESSION_SETUP_ANDX *)smb_buf;
+	rc = sess_sendreceive(sess_data);
 
-	capabilities = cifs_ssetup_hdr(ses, pSMB);
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
 
-	/* we will send the SMB in three pieces:
-	a fixed length beginning part, an optional
-	SPNEGO blob (which can be zero length), and a
-	last part which will include the strings
-	and rest of bcc area. This allows us to avoid
-	a large buffer 17K allocation */
-	iov[0].iov_base = (char *)pSMB;
-	iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
-
-	/* setting this here allows the code at the end of the function
-	   to free the request buffer if there's an error */
-	resp_buf_type = CIFS_SMALL_BUFFER;
+	/* If true, rc here is expected and not an error */
+	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
+	    smb_buf->Status.CifsError ==
+			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
+		rc = 0;
 
-	/* 2000 big enough to fit max user, domain, NOS name etc. */
-	str_area = kmalloc(2000, GFP_KERNEL);
-	if (str_area == NULL) {
-		rc = -ENOMEM;
-		goto ssetup_exit;
+	if (rc)
+		goto out;
+
+	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
+
+	if (smb_buf->WordCount != 4) {
+		rc = -EIO;
+		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
+		goto out;
 	}
-	bcc_ptr = str_area;
 
-	iov[1].iov_base = NULL;
-	iov[1].iov_len = 0;
+	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
+	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
 
-	if (type == RawNTLMSSP) {
-		if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
-			cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
-			rc = -ENOSYS;
-			goto ssetup_exit;
-		}
+	bytes_remaining = get_bcc(smb_buf);
+	bcc_ptr = pByteArea(smb_buf);
 
-		cifs_dbg(FYI, "ntlmssp session setup phase %d\n", phase);
-		pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
-		capabilities |= CAP_EXTENDED_SECURITY;
-		pSMB->req.Capabilities |= cpu_to_le32(capabilities);
-		switch(phase) {
-		case NtLmNegotiate:
-			build_ntlmssp_negotiate_blob(
-				pSMB->req.SecurityBlob, ses);
-			iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
-			iov[1].iov_base = pSMB->req.SecurityBlob;
-			pSMB->req.SecurityBlobLength =
-				cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
-			break;
-		case NtLmAuthenticate:
-			/*
-			 * 5 is an empirical value, large enough to hold
-			 * authenticate message plus max 10 of av paris,
-			 * domain, user, workstation names, flags, etc.
-			 */
-			ntlmsspblob = kzalloc(
-				5*sizeof(struct _AUTHENTICATE_MESSAGE),
-				GFP_KERNEL);
-			if (!ntlmsspblob) {
-				rc = -ENOMEM;
-				goto ssetup_exit;
-			}
+	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
+	if (blob_len > bytes_remaining) {
+		cifs_dbg(VFS, "bad security blob length %d\n",
+				blob_len);
+		rc = -EINVAL;
+		goto out;
+	}
 
-			rc = build_ntlmssp_auth_blob(ntlmsspblob,
-						&blob_len, ses, nls_cp);
-			if (rc)
-				goto ssetup_exit;
-			iov[1].iov_len = blob_len;
-			iov[1].iov_base = ntlmsspblob;
-			pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
-			/*
-			 * Make sure that we tell the server that we are using
-			 * the uid that it just gave us back on the response
-			 * (challenge)
-			 */
-			smb_buf->Uid = ses->Suid;
-			break;
-		default:
-			cifs_dbg(VFS, "invalid phase %d\n", phase);
-			rc = -ENOSYS;
-			goto ssetup_exit;
-		}
-		/* unicode strings must be word aligned */
-		if ((iov[0].iov_len + iov[1].iov_len) % 2) {
-			*bcc_ptr = 0;
-			bcc_ptr++;
-		}
-		unicode_oslm_strings(&bcc_ptr, nls_cp);
-	} else {
-		cifs_dbg(VFS, "secType %d not supported!\n", type);
-		rc = -ENOSYS;
-		goto ssetup_exit;
+	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
+out:
+	sess_free_buffer(sess_data);
+
+	if (!rc) {
+		sess_data->func = sess_auth_rawntlmssp_authenticate;
+		return;
 	}
 
-	iov[2].iov_base = str_area;
-	iov[2].iov_len = (long) bcc_ptr - (long) str_area;
+	/* Else error. Cleanup */
+	kfree(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+	kfree(ses->ntlmssp);
+	ses->ntlmssp = NULL;
 
-	count = iov[1].iov_len + iov[2].iov_len;
-	smb_buf->smb_buf_length =
-		cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
+	sess_data->func = NULL;
+	sess_data->result = rc;
+}
 
-	put_bcc(count, smb_buf);
+static void
+sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
+{
+	int rc;
+	struct smb_hdr *smb_buf;
+	SESSION_SETUP_ANDX *pSMB;
+	struct cifs_ses *ses = sess_data->ses;
+	__u16 bytes_remaining;
+	char *bcc_ptr;
+	char *ntlmsspblob = NULL;
+	u16 blob_len;
 
-	rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
-			  CIFS_LOG_ERROR);
-	/* SMB request buf freed in SendReceive2 */
+	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
 
-	pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
-	smb_buf = (struct smb_hdr *)iov[0].iov_base;
+	/* wct = 12 */
+	rc = sess_alloc_buffer(sess_data, 12);
+	if (rc)
+		goto out;
 
-	if ((type == RawNTLMSSP) && (resp_buf_type != CIFS_NO_BUFFER) &&
-	    (smb_buf->Status.CifsError ==
-			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
-		if (phase != NtLmNegotiate) {
-			cifs_dbg(VFS, "Unexpected more processing error\n");
-			goto ssetup_exit;
-		}
-		/* NTLMSSP Negotiate sent now processing challenge (response) */
-		phase = NtLmChallenge; /* process ntlmssp challenge */
-		rc = 0; /* MORE_PROC rc is not an error here, but expected */
+	/* Build security blob before we assemble the request */
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)pSMB;
+	/*
+	 * 5 is an empirical value, large enough to hold
+	 * authenticate message plus max 10 of av paris,
+	 * domain, user, workstation names, flags, etc.
+	 */
+	ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE),
+				GFP_KERNEL);
+	if (!ntlmsspblob) {
+		rc = -ENOMEM;
+		goto out;
 	}
+
+	rc = build_ntlmssp_auth_blob(ntlmsspblob,
+					&blob_len, ses, sess_data->nls_cp);
+	if (rc)
+		goto out_free_ntlmsspblob;
+	sess_data->iov[1].iov_len = blob_len;
+	sess_data->iov[1].iov_base = ntlmsspblob;
+	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
+	/*
+	 * Make sure that we tell the server that we are using
+	 * the uid that it just gave us back on the response
+	 * (challenge)
+	 */
+	smb_buf->Uid = ses->Suid;
+
+	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
 	if (rc)
-		goto ssetup_exit;
+		goto out_free_ntlmsspblob;
 
+	rc = sess_sendreceive(sess_data);
+	if (rc)
+		goto out_free_ntlmsspblob;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
 	if (smb_buf->WordCount != 4) {
 		rc = -EIO;
 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
-		goto ssetup_exit;
+		goto out_free_ntlmsspblob;
 	}
-	action = le16_to_cpu(pSMB->resp.Action);
-	if (action & GUEST_LOGIN)
+
+	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
-	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
-	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
-	/* response can have either 3 or 4 word count - Samba sends 3 */
-	/* and lanman response is 3 */
+
 	bytes_remaining = get_bcc(smb_buf);
 	bcc_ptr = pByteArea(smb_buf);
-
 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
 	if (blob_len > bytes_remaining) {
 		cifs_dbg(VFS, "bad security blob length %d\n",
-			 blob_len);
+				blob_len);
 		rc = -EINVAL;
-		goto ssetup_exit;
-	}
-	if (phase == NtLmChallenge) {
-		rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
-		if (rc)
-			goto ssetup_exit;
+		goto out_free_ntlmsspblob;
 	}
 	bcc_ptr += blob_len;
 	bytes_remaining -= blob_len;
 
+
 	/* BB check if Unicode and decode strings */
 	if (bytes_remaining == 0) {
 		/* no string area to decode, do nothing */
@@ -1357,61 +1341,113 @@ ssetup_ntlmssp_authenticate:
 			++bcc_ptr;
 			--bytes_remaining;
 		}
-		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
+		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
+				      sess_data->nls_cp);
 	} else {
-		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
+		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
+				    sess_data->nls_cp);
 	}
 
-ssetup_exit:
-	kfree(str_area);
+out_free_ntlmsspblob:
 	kfree(ntlmsspblob);
-	ntlmsspblob = NULL;
-	if (resp_buf_type == CIFS_SMALL_BUFFER) {
-		cifs_dbg(FYI, "ssetup freeing small buf %p\n", iov[0].iov_base);
-		cifs_small_buf_release(iov[0].iov_base);
-	} else if (resp_buf_type == CIFS_LARGE_BUFFER)
-		cifs_buf_release(iov[0].iov_base);
-
-	/* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
-	if ((phase == NtLmChallenge) && (rc == 0))
-		goto ssetup_ntlmssp_authenticate;
-
-	if (!rc) {
-		mutex_lock(&ses->server->srv_mutex);
-		if (!ses->server->session_estab) {
-			if (ses->server->sign) {
-				ses->server->session_key.response =
-					kmemdup(ses->auth_key.response,
-					ses->auth_key.len, GFP_KERNEL);
-				if (!ses->server->session_key.response) {
-					rc = -ENOMEM;
-					mutex_unlock(&ses->server->srv_mutex);
-					goto keycp_exit;
-				}
-				ses->server->session_key.len =
-							ses->auth_key.len;
-			}
-			ses->server->sequence_number = 0x2;
-			ses->server->session_estab = true;
-		}
-		mutex_unlock(&ses->server->srv_mutex);
+out:
+	sess_free_buffer(sess_data);
 
-		cifs_dbg(FYI, "CIFS session established successfully\n");
-		spin_lock(&GlobalMid_Lock);
-		ses->status = CifsGood;
-		ses->need_reconnect = false;
-		spin_unlock(&GlobalMid_Lock);
-	}
+	 if (!rc)
+		rc = sess_establish_session(sess_data);
 
-keycp_exit:
+	/* Cleanup */
 	kfree(ses->auth_key.response);
 	ses->auth_key.response = NULL;
 	kfree(ses->ntlmssp);
+	ses->ntlmssp = NULL;
 
-	return rc;
+	sess_data->func = NULL;
+	sess_data->result = rc;
+}
 
-out:
+int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
+{
+	int type;
+
+	type = select_sectype(ses->server, ses->sectype);
+	cifs_dbg(FYI, "sess setup type %d\n", type);
+	if (type == Unspecified) {
+		cifs_dbg(VFS,
+			"Unable to select appropriate authentication method!");
+		return -EINVAL;
+	}
+
+	switch (type) {
+	case LANMAN:
+		/* LANMAN and plaintext are less secure and off by default.
+		 * So we make this explicitly be turned on in kconfig (in the
+		 * build) and turned on at runtime (changed from the default)
+		 * in proc/fs/cifs or via mount parm.  Unfortunately this is
+		 * needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+		sess_data->func = sess_auth_lanman;
+		break;
+#else
+		return -EOPNOTSUPP;
+#endif
+	case NTLM:
+		sess_data->func = sess_auth_ntlm;
+		break;
+	case NTLMv2:
+		sess_data->func = sess_auth_ntlmv2;
+		break;
+	case Kerberos:
+#ifdef CONFIG_CIFS_UPCALL
+		sess_data->func = sess_auth_kerberos;
+		break;
+#else
+		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
+		return -ENOSYS;
+		break;
+#endif /* CONFIG_CIFS_UPCALL */
+	case RawNTLMSSP:
+		sess_data->func = sess_auth_rawntlmssp_negotiate;
+		break;
+	default:
+		cifs_dbg(VFS, "secType %d not supported!\n", type);
+		return -ENOSYS;
+	}
+
+	return 0;
+}
+
+int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
+		    const struct nls_table *nls_cp)
+{
+	int rc = 0;
+	struct sess_data *sess_data;
+
+	if (ses == NULL) {
+		WARN(1, "%s: ses == NULL!", __func__);
+		return -EINVAL;
+	}
+
+	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
+	if (!sess_data)
+		return -ENOMEM;
+
+	rc = select_sec(ses, sess_data);
+	if (rc)
+		goto out;
+
+	sess_data->xid = xid;
+	sess_data->ses = ses;
+	sess_data->buf0_type = CIFS_NO_BUFFER;
+	sess_data->nls_cp = (struct nls_table *) nls_cp;
+
+	while (sess_data->func)
+		sess_data->func(sess_data);
+
+	/* Store result before we free sess_data */
 	rc = sess_data->result;
+
+out:
 	kfree(sess_data);
 	return rc;
 }
-- 
1.9.3

Re: [PATCH 1/5] cifs: replace code with free_rsp_buf()

[Shirish Pargaonkar]

Looks correct.

Reviewed-by: Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>

On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> The functionality provided by free_rsp_buf() is duplicated in a number
> of places. Replace these instances with a call to free_rsp_buf().
>
> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  fs/cifs/cifsproto.h |  1 +
>  fs/cifs/cifssmb.c   | 20 ++++----------------
>  fs/cifs/misc.c      |  9 +++++++++
>  fs/cifs/smb2pdu.c   | 10 ----------
>  4 files changed, 14 insertions(+), 26 deletions(-)
>
> diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
> index ca7980a..de49d7a 100644
> --- a/fs/cifs/cifsproto.h
> +++ b/fs/cifs/cifsproto.h
> @@ -36,6 +36,7 @@ extern struct smb_hdr *cifs_buf_get(void);
>  extern void cifs_buf_release(void *);
>  extern struct smb_hdr *cifs_small_buf_get(void);
>  extern void cifs_small_buf_release(void *);
> +extern void free_rsp_buf(int, void *);
>  extern void cifs_rqst_page_to_kvec(struct smb_rqst *rqst, unsigned int idx,
>                                         struct kvec *iov);
>  extern int smb_send(struct TCP_Server_Info *, struct smb_hdr *,
> diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
> index 6ce4e09..b7e5b65 100644
> --- a/fs/cifs/cifssmb.c
> +++ b/fs/cifs/cifssmb.c
> @@ -1734,10 +1734,7 @@ CIFSSMBRead(const unsigned int xid, struct cifs_io_parms *io_parms,
>
>  /*     cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
>         if (*buf) {
> -               if (resp_buf_type == CIFS_SMALL_BUFFER)
> -                       cifs_small_buf_release(iov[0].iov_base);
> -               else if (resp_buf_type == CIFS_LARGE_BUFFER)
> -                       cifs_buf_release(iov[0].iov_base);
> +               free_rsp_buf(resp_buf_type, iov[0].iov_base);
>         } else if (resp_buf_type != CIFS_NO_BUFFER) {
>                 /* return buffer to caller to free */
>                 *buf = iov[0].iov_base;
> @@ -2203,10 +2200,7 @@ CIFSSMBWrite2(const unsigned int xid, struct cifs_io_parms *io_parms,
>         }
>
>  /*     cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
> -       if (resp_buf_type == CIFS_SMALL_BUFFER)
> -               cifs_small_buf_release(iov[0].iov_base);
> -       else if (resp_buf_type == CIFS_LARGE_BUFFER)
> -               cifs_buf_release(iov[0].iov_base);
> +       free_rsp_buf(resp_buf_type, iov[0].iov_base);
>
>         /* Note: On -EAGAIN error only caller can retry on handle based calls
>                 since file handle passed in no longer valid */
> @@ -2451,10 +2445,7 @@ plk_err_exit:
>         if (pSMB)
>                 cifs_small_buf_release(pSMB);
>
> -       if (resp_buf_type == CIFS_SMALL_BUFFER)
> -               cifs_small_buf_release(iov[0].iov_base);
> -       else if (resp_buf_type == CIFS_LARGE_BUFFER)
> -               cifs_buf_release(iov[0].iov_base);
> +       free_rsp_buf(resp_buf_type, iov[0].iov_base);
>
>         /* Note: On -EAGAIN error only caller can retry on handle based calls
>            since file handle passed in no longer valid */
> @@ -3838,10 +3829,7 @@ CIFSSMBGetCIFSACL(const unsigned int xid, struct cifs_tcon *tcon, __u16 fid,
>                 }
>         }
>  qsec_out:
> -       if (buf_type == CIFS_SMALL_BUFFER)
> -               cifs_small_buf_release(iov[0].iov_base);
> -       else if (buf_type == CIFS_LARGE_BUFFER)
> -               cifs_buf_release(iov[0].iov_base);
> +       free_rsp_buf(buf_type, iov[0].iov_base);
>  /*     cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
>         return rc;
>  }
> diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
> index 3b0c62e..64997a0 100644
> --- a/fs/cifs/misc.c
> +++ b/fs/cifs/misc.c
> @@ -226,6 +226,15 @@ cifs_small_buf_release(void *buf_to_free)
>         return;
>  }
>
> +void
> +free_rsp_buf(int resp_buftype, void *rsp)
> +{
> +       if (resp_buftype == CIFS_SMALL_BUFFER)
> +               cifs_small_buf_release(rsp);
> +       else if (resp_buftype == CIFS_LARGE_BUFFER)
> +               cifs_buf_release(rsp);
> +}
> +
>  /* NB: MID can not be set if treeCon not passed in, in that
>     case it is responsbility of caller to set the mid */
>  void
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> index b0b260d..0158104 100644
> --- a/fs/cifs/smb2pdu.c
> +++ b/fs/cifs/smb2pdu.c
> @@ -309,16 +309,6 @@ small_smb2_init(__le16 smb2_command, struct cifs_tcon *tcon,
>         return rc;
>  }
>
> -static void
> -free_rsp_buf(int resp_buftype, void *rsp)
> -{
> -       if (resp_buftype == CIFS_SMALL_BUFFER)
> -               cifs_small_buf_release(rsp);
> -       else if (resp_buftype == CIFS_LARGE_BUFFER)
> -               cifs_buf_release(rsp);
> -}
> -
> -
>  /*
>   *
>   *     SMB2 Worker functions follow:
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 2/5] cifs: Split lanman auth from CIFS_SessSetup()

[Shirish Pargaonkar]

Looks correct.

Reviewed-by:  Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>

On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> In preparation for splitting CIFS_SessSetup() into smaller more
> manageable chunks, we first add helper functions.
>
> We then proceed to split out lanman auth out of CIFS_SessSetup()
>
> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  fs/cifs/sess.c | 303 ++++++++++++++++++++++++++++++++++++++++++++++++---------
>  1 file changed, 258 insertions(+), 45 deletions(-)
>
> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
> index e87387d..36d0b90 100644
> --- a/fs/cifs/sess.c
> +++ b/fs/cifs/sess.c
> @@ -520,6 +520,240 @@ select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
>         }
>  }
>
> +struct sess_data {
> +       unsigned int xid;
> +       struct cifs_ses *ses;
> +       struct nls_table *nls_cp;
> +       void (*func)(struct sess_data *);
> +       int result;
> +
> +       /* we will send the SMB in three pieces:
> +        * a fixed length beginning part, an optional
> +        * SPNEGO blob (which can be zero length), and a
> +        * last part which will include the strings
> +        * and rest of bcc area. This allows us to avoid
> +        * a large buffer 17K allocation
> +        */
> +       int buf0_type;
> +       struct kvec iov[3];
> +};
> +
> +static int
> +sess_alloc_buffer(struct sess_data *sess_data, int wct)
> +{
> +       int rc;
> +       struct cifs_ses *ses = sess_data->ses;
> +       struct smb_hdr *smb_buf;
> +
> +       rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
> +                                 (void **)&smb_buf);
> +
> +       if (rc)
> +               return rc;
> +
> +       sess_data->iov[0].iov_base = (char *)smb_buf;
> +       sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
> +       /*
> +        * This variable will be used to clear the buffer
> +        * allocated above in case of any error in the calling function.
> +        */
> +       sess_data->buf0_type = CIFS_SMALL_BUFFER;
> +
> +       /* 2000 big enough to fit max user, domain, NOS name etc. */
> +       sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
> +       if (!sess_data->iov[2].iov_base) {
> +               rc = -ENOMEM;
> +               goto out_free_smb_buf;
> +       }
> +
> +       return 0;
> +
> +out_free_smb_buf:
> +       kfree(smb_buf);
> +       sess_data->iov[0].iov_base = NULL;
> +       sess_data->iov[0].iov_len = 0;
> +       sess_data->buf0_type = CIFS_NO_BUFFER;
> +       return rc;
> +}
> +
> +static void
> +sess_free_buffer(struct sess_data *sess_data)
> +{
> +
> +       free_rsp_buf(sess_data->buf0_type, sess_data->iov[0].iov_base);
> +       sess_data->buf0_type = CIFS_NO_BUFFER;
> +       kfree(sess_data->iov[2].iov_base);
> +}
> +
> +static int
> +sess_establish_session(struct sess_data *sess_data)
> +{
> +       struct cifs_ses *ses = sess_data->ses;
> +
> +       mutex_lock(&ses->server->srv_mutex);
> +       if (!ses->server->session_estab) {
> +               if (ses->server->sign) {
> +                       ses->server->session_key.response =
> +                               kmemdup(ses->auth_key.response,
> +                               ses->auth_key.len, GFP_KERNEL);
> +                       if (!ses->server->session_key.response) {
> +                               mutex_unlock(&ses->server->srv_mutex);
> +                               return -ENOMEM;
> +                       }
> +                       ses->server->session_key.len =
> +                                               ses->auth_key.len;
> +               }
> +               ses->server->sequence_number = 0x2;
> +               ses->server->session_estab = true;
> +       }
> +       mutex_unlock(&ses->server->srv_mutex);
> +
> +       cifs_dbg(FYI, "CIFS session established successfully\n");
> +       spin_lock(&GlobalMid_Lock);
> +       ses->status = CifsGood;
> +       ses->need_reconnect = false;
> +       spin_unlock(&GlobalMid_Lock);
> +
> +       return 0;
> +}
> +
> +static int
> +sess_sendreceive(struct sess_data *sess_data)
> +{
> +       int rc;
> +       struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
> +       __u16 count;
> +
> +       count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
> +       smb_buf->smb_buf_length =
> +               cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
> +       put_bcc(count, smb_buf);
> +
> +       rc = SendReceive2(sess_data->xid, sess_data->ses,
> +                         sess_data->iov, 3 /* num_iovecs */,
> +                         &sess_data->buf0_type,
> +                         CIFS_LOG_ERROR);
> +
> +       return rc;
> +}
> +
> +/*
> + * LANMAN and plaintext are less secure and off by default.
> + * So we make this explicitly be turned on in kconfig (in the
> + * build) and turned on at runtime (changed from the default)
> + * in proc/fs/cifs or via mount parm.  Unfortunately this is
> + * needed for old Win (e.g. Win95), some obscure NAS and OS/2
> + */
> +#ifdef CONFIG_CIFS_WEAK_PW_HASH
> +static void
> +sess_auth_lanman(struct sess_data *sess_data)
> +{
> +       int rc = 0;
> +       struct smb_hdr *smb_buf;
> +       SESSION_SETUP_ANDX *pSMB;
> +       char *bcc_ptr;
> +       struct cifs_ses *ses = sess_data->ses;
> +       char lnm_session_key[CIFS_AUTH_RESP_SIZE];
> +       __u32 capabilities;
> +       __u16 bytes_remaining;
> +
> +       /* lanman 2 style sessionsetup */
> +       /* wct = 10 */
> +       rc = sess_alloc_buffer(sess_data, 10);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       bcc_ptr = sess_data->iov[2].iov_base;
> +       capabilities = cifs_ssetup_hdr(ses, pSMB);
> +
> +       pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
> +
> +       /* no capabilities flags in old lanman negotiation */
> +       pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> +
> +       /* Calculate hash with password and copy into bcc_ptr.
> +        * Encryption Key (stored as in cryptkey) gets used if the
> +        * security mode bit in Negottiate Protocol response states
> +        * to use challenge/response method (i.e. Password bit is 1).
> +        */
> +       rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
> +                             ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
> +                             true : false, lnm_session_key);
> +
> +       memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
> +       bcc_ptr += CIFS_AUTH_RESP_SIZE;
> +
> +       /*
> +        * can not sign if LANMAN negotiated so no need
> +        * to calculate signing key? but what if server
> +        * changed to do higher than lanman dialect and
> +        * we reconnected would we ever calc signing_key?
> +        */
> +
> +       cifs_dbg(FYI, "Negotiating LANMAN setting up strings\n");
> +       /* Unicode not allowed for LANMAN dialects */
> +       ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
> +
> +       sess_data->iov[2].iov_len = (long) bcc_ptr -
> +                       (long) sess_data->iov[2].iov_base;
> +
> +       rc = sess_sendreceive(sess_data);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
> +
> +       /* lanman response has a word count of 3 */
> +       if (smb_buf->WordCount != 3) {
> +               rc = -EIO;
> +               cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
> +               goto out;
> +       }
> +
> +       if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
> +               cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
> +
> +       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
> +       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
> +
> +       bytes_remaining = get_bcc(smb_buf);
> +       bcc_ptr = pByteArea(smb_buf);
> +
> +       /* BB check if Unicode and decode strings */
> +       if (bytes_remaining == 0) {
> +               /* no string area to decode, do nothing */
> +       } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> +               /* unicode string area must be word-aligned */
> +               if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> +                       ++bcc_ptr;
> +                       --bytes_remaining;
> +               }
> +               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                     sess_data->nls_cp);
> +       } else {
> +               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                   sess_data->nls_cp);
> +       }
> +
> +       rc = sess_establish_session(sess_data);
> +out:
> +       sess_data->result = rc;
> +       sess_data->func = NULL;
> +       sess_free_buffer(sess_data);
> +}
> +
> +#else
> +
> +static void
> +sess_auth_lanman(struct sess_data *sess_data)
> +{
> +       sess_data->result = -EOPNOTSUPP;
> +       sess_data->func = NULL;
> +}
> +#endif
> +
>  int
>  CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>                const struct nls_table *nls_cp)
> @@ -540,12 +774,21 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>         __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
>         u16 blob_len;
>         char *ntlmsspblob = NULL;
> +       struct sess_data *sess_data;
>
>         if (ses == NULL) {
>                 WARN(1, "%s: ses == NULL!", __func__);
>                 return -EINVAL;
>         }
>
> +       sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
> +       if (!sess_data)
> +               return -ENOMEM;
> +       sess_data->xid = xid;
> +       sess_data->ses = ses;
> +       sess_data->buf0_type = CIFS_NO_BUFFER;
> +       sess_data->nls_cp = (struct nls_table *) nls_cp;
> +
>         type = select_sectype(ses->server, ses->sectype);
>         cifs_dbg(FYI, "sess setup type %d\n", type);
>         if (type == Unspecified) {
> @@ -554,6 +797,14 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>                 return -EINVAL;
>         }
>
> +       switch (type) {
> +       case LANMAN:
> +               sess_auth_lanman(sess_data);
> +               goto out;
> +       default:
> +               cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
> +       }
> +
>         if (type == RawNTLMSSP) {
>                 /* if memory allocation is successful, caller of this function
>                  * frees it.
> @@ -569,17 +820,7 @@ ssetup_ntlmssp_authenticate:
>         if (phase == NtLmChallenge)
>                 phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
>
> -       if (type == LANMAN) {
> -#ifndef CONFIG_CIFS_WEAK_PW_HASH
> -               /* LANMAN and plaintext are less secure and off by default.
> -               So we make this explicitly be turned on in kconfig (in the
> -               build) and turned on at runtime (changed from the default)
> -               in proc/fs/cifs or via mount parm.  Unfortunately this is
> -               needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
> -               return -EOPNOTSUPP;
> -#endif
> -               wct = 10; /* lanman 2 style sessionsetup */
> -       } else if ((type == NTLM) || (type == NTLMv2)) {
> +       if ((type == NTLM) || (type == NTLMv2)) {
>                 /* For NTLMv2 failures eventually may need to retry NTLM */
>                 wct = 13; /* old style NTLM sessionsetup */
>         } else /* same size: negotiate or auth, NTLMSSP or extended security */
> @@ -618,39 +859,7 @@ ssetup_ntlmssp_authenticate:
>         iov[1].iov_base = NULL;
>         iov[1].iov_len = 0;
>
> -       if (type == LANMAN) {
> -#ifdef CONFIG_CIFS_WEAK_PW_HASH
> -               char lnm_session_key[CIFS_AUTH_RESP_SIZE];
> -
> -               pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
> -
> -               /* no capabilities flags in old lanman negotiation */
> -
> -               pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> -
> -               /* Calculate hash with password and copy into bcc_ptr.
> -                * Encryption Key (stored as in cryptkey) gets used if the
> -                * security mode bit in Negottiate Protocol response states
> -                * to use challenge/response method (i.e. Password bit is 1).
> -                */
> -
> -               rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
> -                                ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
> -                                       true : false, lnm_session_key);
> -
> -               memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
> -               bcc_ptr += CIFS_AUTH_RESP_SIZE;
> -
> -               /* can not sign if LANMAN negotiated so no need
> -               to calculate signing key? but what if server
> -               changed to do higher than lanman dialect and
> -               we reconnected would we ever calc signing_key? */
> -
> -               cifs_dbg(FYI, "Negotiating LANMAN setting up strings\n");
> -               /* Unicode not allowed for LANMAN dialects */
> -               ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
> -#endif
> -       } else if (type == NTLM) {
> +       if (type == NTLM) {
>                 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
>                 pSMB->req_no_secext.CaseInsensitivePasswordLength =
>                         cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> @@ -889,7 +1098,6 @@ ssetup_ntlmssp_authenticate:
>                 }
>                 if (phase == NtLmChallenge) {
>                         rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
> -                       /* now goto beginning for ntlmssp authenticate phase */
>                         if (rc)
>                                 goto ssetup_exit;
>                 }
> @@ -962,4 +1170,9 @@ keycp_exit:
>         kfree(ses->ntlmssp);
>
>         return rc;
> +
> +out:
> +       rc = sess_data->result;
> +       kfree(sess_data);
> +       return rc;
>  }
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
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Re: [PATCH 3/5] cifs: Split ntlm and ntlmv2 authentication methods off CIFS_SessSetup()

[Shirish Pargaonkar]

Looks correct.

Reviewed-by: Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>

On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  fs/cifs/sess.c | 316 ++++++++++++++++++++++++++++++++++++++++++---------------
>  1 file changed, 232 insertions(+), 84 deletions(-)
>
> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
> index 36d0b90..4f481c1 100644
> --- a/fs/cifs/sess.c
> +++ b/fs/cifs/sess.c
> @@ -754,6 +754,216 @@ sess_auth_lanman(struct sess_data *sess_data)
>  }
>  #endif
>
> +static void
> +sess_auth_ntlm(struct sess_data *sess_data)
> +{
> +       int rc = 0;
> +       struct smb_hdr *smb_buf;
> +       SESSION_SETUP_ANDX *pSMB;
> +       char *bcc_ptr;
> +       struct cifs_ses *ses = sess_data->ses;
> +       __u32 capabilities;
> +       __u16 bytes_remaining;
> +
> +       /* old style NTLM sessionsetup */
> +       /* wct = 13 */
> +       rc = sess_alloc_buffer(sess_data, 13);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       bcc_ptr = sess_data->iov[2].iov_base;
> +       capabilities = cifs_ssetup_hdr(ses, pSMB);
> +
> +       pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
> +       pSMB->req_no_secext.CaseInsensitivePasswordLength =
> +                       cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> +       pSMB->req_no_secext.CaseSensitivePasswordLength =
> +                       cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> +
> +       /* calculate ntlm response and session key */
> +       rc = setup_ntlm_response(ses, sess_data->nls_cp);
> +       if (rc) {
> +               cifs_dbg(VFS, "Error %d during NTLM authentication\n",
> +                                rc);
> +               goto out;
> +       }
> +
> +       /* copy ntlm response */
> +       memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
> +                       CIFS_AUTH_RESP_SIZE);
> +       bcc_ptr += CIFS_AUTH_RESP_SIZE;
> +       memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
> +                       CIFS_AUTH_RESP_SIZE);
> +       bcc_ptr += CIFS_AUTH_RESP_SIZE;
> +
> +       if (ses->capabilities & CAP_UNICODE) {
> +               /* unicode strings must be word aligned */
> +               if (sess_data->iov[0].iov_len % 2) {
> +                       *bcc_ptr = 0;
> +                       bcc_ptr++;
> +               }
> +               unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
> +       } else {
> +               ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
> +       }
> +
> +
> +       sess_data->iov[2].iov_len = (long) bcc_ptr -
> +                       (long) sess_data->iov[2].iov_base;
> +
> +       rc = sess_sendreceive(sess_data);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
> +
> +       if (smb_buf->WordCount != 3) {
> +               rc = -EIO;
> +               cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
> +               goto out;
> +       }
> +
> +       if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
> +               cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
> +
> +       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
> +       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
> +
> +       bytes_remaining = get_bcc(smb_buf);
> +       bcc_ptr = pByteArea(smb_buf);
> +
> +       /* BB check if Unicode and decode strings */
> +       if (bytes_remaining == 0) {
> +               /* no string area to decode, do nothing */
> +       } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> +               /* unicode string area must be word-aligned */
> +               if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> +                       ++bcc_ptr;
> +                       --bytes_remaining;
> +               }
> +               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                     sess_data->nls_cp);
> +       } else {
> +               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                   sess_data->nls_cp);
> +       }
> +
> +       rc = sess_establish_session(sess_data);
> +out:
> +       sess_data->result = rc;
> +       sess_data->func = NULL;
> +       sess_free_buffer(sess_data);
> +       kfree(ses->auth_key.response);
> +       ses->auth_key.response = NULL;
> +}
> +
> +static void
> +sess_auth_ntlmv2(struct sess_data *sess_data)
> +{
> +       int rc = 0;
> +       struct smb_hdr *smb_buf;
> +       SESSION_SETUP_ANDX *pSMB;
> +       char *bcc_ptr;
> +       struct cifs_ses *ses = sess_data->ses;
> +       __u32 capabilities;
> +       __u16 bytes_remaining;
> +
> +       /* old style NTLM sessionsetup */
> +       /* wct = 13 */
> +       rc = sess_alloc_buffer(sess_data, 13);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       bcc_ptr = sess_data->iov[2].iov_base;
> +       capabilities = cifs_ssetup_hdr(ses, pSMB);
> +
> +       pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
> +
> +       /* LM2 password would be here if we supported it */
> +       pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
> +
> +       /* calculate nlmv2 response and session key */
> +       rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
> +       if (rc) {
> +               cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
> +               goto out;
> +       }
> +
> +       memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
> +                       ses->auth_key.len - CIFS_SESS_KEY_SIZE);
> +       bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
> +
> +       /* set case sensitive password length after tilen may get
> +        * assigned, tilen is 0 otherwise.
> +        */
> +       pSMB->req_no_secext.CaseSensitivePasswordLength =
> +               cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
> +
> +       if (ses->capabilities & CAP_UNICODE) {
> +               if (sess_data->iov[0].iov_len % 2) {
> +                       *bcc_ptr = 0;
> +                       bcc_ptr++;
> +               }
> +               unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
> +       } else {
> +               ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
> +       }
> +
> +
> +       sess_data->iov[2].iov_len = (long) bcc_ptr -
> +                       (long) sess_data->iov[2].iov_base;
> +
> +       rc = sess_sendreceive(sess_data);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
> +
> +       if (smb_buf->WordCount != 3) {
> +               rc = -EIO;
> +               cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
> +               goto out;
> +       }
> +
> +       if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
> +               cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
> +
> +       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
> +       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
> +
> +       bytes_remaining = get_bcc(smb_buf);
> +       bcc_ptr = pByteArea(smb_buf);
> +
> +       /* BB check if Unicode and decode strings */
> +       if (bytes_remaining == 0) {
> +               /* no string area to decode, do nothing */
> +       } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> +               /* unicode string area must be word-aligned */
> +               if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> +                       ++bcc_ptr;
> +                       --bytes_remaining;
> +               }
> +               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                     sess_data->nls_cp);
> +       } else {
> +               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                   sess_data->nls_cp);
> +       }
> +
> +       rc = sess_establish_session(sess_data);
> +out:
> +       sess_data->result = rc;
> +       sess_data->func = NULL;
> +       sess_free_buffer(sess_data);
> +       kfree(ses->auth_key.response);
> +       ses->auth_key.response = NULL;
> +}
> +
> +
>  int
>  CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>                const struct nls_table *nls_cp)
> @@ -801,6 +1011,12 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>         case LANMAN:
>                 sess_auth_lanman(sess_data);
>                 goto out;
> +       case NTLM:
> +               sess_auth_ntlm(sess_data);
> +               goto out;
> +       case NTLMv2:
> +               sess_auth_ntlmv2(sess_data);
> +               goto out;
>         default:
>                 cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
>         }
> @@ -820,11 +1036,8 @@ ssetup_ntlmssp_authenticate:
>         if (phase == NtLmChallenge)
>                 phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
>
> -       if ((type == NTLM) || (type == NTLMv2)) {
> -               /* For NTLMv2 failures eventually may need to retry NTLM */
> -               wct = 13; /* old style NTLM sessionsetup */
> -       } else /* same size: negotiate or auth, NTLMSSP or extended security */
> -               wct = 12;
> +       /* same size: negotiate or auth, NTLMSSP or extended security */
> +       wct = 12;
>
>         rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
>                             (void **)&smb_buf);
> @@ -859,70 +1072,7 @@ ssetup_ntlmssp_authenticate:
>         iov[1].iov_base = NULL;
>         iov[1].iov_len = 0;
>
> -       if (type == NTLM) {
> -               pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
> -               pSMB->req_no_secext.CaseInsensitivePasswordLength =
> -                       cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> -               pSMB->req_no_secext.CaseSensitivePasswordLength =
> -                       cpu_to_le16(CIFS_AUTH_RESP_SIZE);
> -
> -               /* calculate ntlm response and session key */
> -               rc = setup_ntlm_response(ses, nls_cp);
> -               if (rc) {
> -                       cifs_dbg(VFS, "Error %d during NTLM authentication\n",
> -                                rc);
> -                       goto ssetup_exit;
> -               }
> -
> -               /* copy ntlm response */
> -               memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
> -                               CIFS_AUTH_RESP_SIZE);
> -               bcc_ptr += CIFS_AUTH_RESP_SIZE;
> -               memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
> -                               CIFS_AUTH_RESP_SIZE);
> -               bcc_ptr += CIFS_AUTH_RESP_SIZE;
> -
> -               if (ses->capabilities & CAP_UNICODE) {
> -                       /* unicode strings must be word aligned */
> -                       if (iov[0].iov_len % 2) {
> -                               *bcc_ptr = 0;
> -                               bcc_ptr++;
> -                       }
> -                       unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
> -               } else
> -                       ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
> -       } else if (type == NTLMv2) {
> -               pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
> -
> -               /* LM2 password would be here if we supported it */
> -               pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
> -
> -               /* calculate nlmv2 response and session key */
> -               rc = setup_ntlmv2_rsp(ses, nls_cp);
> -               if (rc) {
> -                       cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n",
> -                                rc);
> -                       goto ssetup_exit;
> -               }
> -               memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
> -                               ses->auth_key.len - CIFS_SESS_KEY_SIZE);
> -               bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
> -
> -               /* set case sensitive password length after tilen may get
> -                * assigned, tilen is 0 otherwise.
> -                */
> -               pSMB->req_no_secext.CaseSensitivePasswordLength =
> -                       cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
> -
> -               if (ses->capabilities & CAP_UNICODE) {
> -                       if (iov[0].iov_len % 2) {
> -                               *bcc_ptr = 0;
> -                               bcc_ptr++;
> -                       }
> -                       unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
> -               } else
> -                       ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
> -       } else if (type == Kerberos) {
> +       if (type == Kerberos) {
>  #ifdef CONFIG_CIFS_UPCALL
>                 struct cifs_spnego_msg *msg;
>
> @@ -1073,7 +1223,7 @@ ssetup_ntlmssp_authenticate:
>         if (rc)
>                 goto ssetup_exit;
>
> -       if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
> +       if (smb_buf->WordCount != 4) {
>                 rc = -EIO;
>                 cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
>                 goto ssetup_exit;
> @@ -1088,22 +1238,20 @@ ssetup_ntlmssp_authenticate:
>         bytes_remaining = get_bcc(smb_buf);
>         bcc_ptr = pByteArea(smb_buf);
>
> -       if (smb_buf->WordCount == 4) {
> -               blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
> -               if (blob_len > bytes_remaining) {
> -                       cifs_dbg(VFS, "bad security blob length %d\n",
> -                                blob_len);
> -                       rc = -EINVAL;
> +       blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
> +       if (blob_len > bytes_remaining) {
> +               cifs_dbg(VFS, "bad security blob length %d\n",
> +                        blob_len);
> +               rc = -EINVAL;
> +               goto ssetup_exit;
> +       }
> +       if (phase == NtLmChallenge) {
> +               rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
> +               if (rc)
>                         goto ssetup_exit;
> -               }
> -               if (phase == NtLmChallenge) {
> -                       rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
> -                       if (rc)
> -                               goto ssetup_exit;
> -               }
> -               bcc_ptr += blob_len;
> -               bytes_remaining -= blob_len;
>         }
> +       bcc_ptr += blob_len;
> +       bytes_remaining -= blob_len;
>
>         /* BB check if Unicode and decode strings */
>         if (bytes_remaining == 0) {
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 4/5] cifs: Split Kerberos authentication off CIFS_SessSetup()

[Shirish Pargaonkar]

Looks correct.

Reviewed-by: Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>

On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  fs/cifs/sess.c | 215 ++++++++++++++++++++++++++++++++++++++++-----------------
>  1 file changed, 153 insertions(+), 62 deletions(-)
>
> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
> index 4f481c1..b413fae 100644
> --- a/fs/cifs/sess.c
> +++ b/fs/cifs/sess.c
> @@ -963,6 +963,155 @@ out:
>         ses->auth_key.response = NULL;
>  }
>
> +#ifdef CONFIG_CIFS_UPCALL
> +static void
> +sess_auth_kerberos(struct sess_data *sess_data)
> +{
> +       int rc = 0;
> +       struct smb_hdr *smb_buf;
> +       SESSION_SETUP_ANDX *pSMB;
> +       char *bcc_ptr;
> +       struct cifs_ses *ses = sess_data->ses;
> +       __u32 capabilities;
> +       __u16 bytes_remaining;
> +       struct key *spnego_key = NULL;
> +       struct cifs_spnego_msg *msg;
> +       u16 blob_len;
> +
> +       /* extended security */
> +       /* wct = 12 */
> +       rc = sess_alloc_buffer(sess_data, 12);
> +       if (rc)
> +               goto out;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       bcc_ptr = sess_data->iov[2].iov_base;
> +       capabilities = cifs_ssetup_hdr(ses, pSMB);
> +
> +       spnego_key = cifs_get_spnego_key(ses);
> +       if (IS_ERR(spnego_key)) {
> +               rc = PTR_ERR(spnego_key);
> +               spnego_key = NULL;
> +               goto out;
> +       }
> +
> +       msg = spnego_key->payload.data;
> +       /*
> +        * check version field to make sure that cifs.upcall is
> +        * sending us a response in an expected form
> +        */
> +       if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
> +               cifs_dbg(VFS,
> +                 "incorrect version of cifs.upcall (expected %d but got %d)",
> +                             CIFS_SPNEGO_UPCALL_VERSION, msg->version);
> +               rc = -EKEYREJECTED;
> +               goto out_put_spnego_key;
> +       }
> +
> +       ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
> +                                        GFP_KERNEL);
> +       if (!ses->auth_key.response) {
> +               cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory",
> +                               msg->sesskey_len);
> +               rc = -ENOMEM;
> +               goto out_put_spnego_key;
> +       }
> +       ses->auth_key.len = msg->sesskey_len;
> +
> +       pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
> +       capabilities |= CAP_EXTENDED_SECURITY;
> +       pSMB->req.Capabilities = cpu_to_le32(capabilities);
> +       sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
> +       sess_data->iov[1].iov_len = msg->secblob_len;
> +       pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
> +
> +       if (ses->capabilities & CAP_UNICODE) {
> +               /* unicode strings must be word aligned */
> +               if ((sess_data->iov[0].iov_len
> +                       + sess_data->iov[1].iov_len) % 2) {
> +                       *bcc_ptr = 0;
> +                       bcc_ptr++;
> +               }
> +               unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
> +               unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
> +       } else {
> +               /* BB: is this right? */
> +               ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
> +       }
> +
> +       sess_data->iov[2].iov_len = (long) bcc_ptr -
> +                       (long) sess_data->iov[2].iov_base;
> +
> +       rc = sess_sendreceive(sess_data);
> +       if (rc)
> +               goto out_put_spnego_key;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
> +
> +       if (smb_buf->WordCount != 4) {
> +               rc = -EIO;
> +               cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
> +               goto out_put_spnego_key;
> +       }
> +
> +       if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
> +               cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
> +
> +       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
> +       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
> +
> +       bytes_remaining = get_bcc(smb_buf);
> +       bcc_ptr = pByteArea(smb_buf);
> +
> +       blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
> +       if (blob_len > bytes_remaining) {
> +               cifs_dbg(VFS, "bad security blob length %d\n",
> +                               blob_len);
> +               rc = -EINVAL;
> +               goto out_put_spnego_key;
> +       }
> +       bcc_ptr += blob_len;
> +       bytes_remaining -= blob_len;
> +
> +       /* BB check if Unicode and decode strings */
> +       if (bytes_remaining == 0) {
> +               /* no string area to decode, do nothing */
> +       } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
> +               /* unicode string area must be word-aligned */
> +               if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
> +                       ++bcc_ptr;
> +                       --bytes_remaining;
> +               }
> +               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                     sess_data->nls_cp);
> +       } else {
> +               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                   sess_data->nls_cp);
> +       }
> +
> +       rc = sess_establish_session(sess_data);
> +out_put_spnego_key:
> +       key_invalidate(spnego_key);
> +       key_put(spnego_key);
> +out:
> +       sess_data->result = rc;
> +       sess_data->func = NULL;
> +       sess_free_buffer(sess_data);
> +       kfree(ses->auth_key.response);
> +       ses->auth_key.response = NULL;
> +}
> +
> +#else
> +
> +static void
> +sess_auth_kerberos(struct sess_data *sess_data)
> +{
> +       cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
> +       sess_data->result = -ENOSYS;
> +       sess_data->func = NULL;
> +}
> +#endif /* ! CONFIG_CIFS_UPCALL */
>
>  int
>  CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
> @@ -980,7 +1129,6 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>         struct kvec iov[3];
>         enum securityEnum type;
>         __u16 action, bytes_remaining;
> -       struct key *spnego_key = NULL;
>         __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
>         u16 blob_len;
>         char *ntlmsspblob = NULL;
> @@ -1017,6 +1165,9 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>         case NTLMv2:
>                 sess_auth_ntlmv2(sess_data);
>                 goto out;
> +       case Kerberos:
> +               sess_auth_kerberos(sess_data);
> +               goto out;
>         default:
>                 cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
>         }
> @@ -1072,63 +1223,7 @@ ssetup_ntlmssp_authenticate:
>         iov[1].iov_base = NULL;
>         iov[1].iov_len = 0;
>
> -       if (type == Kerberos) {
> -#ifdef CONFIG_CIFS_UPCALL
> -               struct cifs_spnego_msg *msg;
> -
> -               spnego_key = cifs_get_spnego_key(ses);
> -               if (IS_ERR(spnego_key)) {
> -                       rc = PTR_ERR(spnego_key);
> -                       spnego_key = NULL;
> -                       goto ssetup_exit;
> -               }
> -
> -               msg = spnego_key->payload.data;
> -               /* check version field to make sure that cifs.upcall is
> -                  sending us a response in an expected form */
> -               if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
> -                       cifs_dbg(VFS, "incorrect version of cifs.upcall "
> -                                  "expected %d but got %d)",
> -                                  CIFS_SPNEGO_UPCALL_VERSION, msg->version);
> -                       rc = -EKEYREJECTED;
> -                       goto ssetup_exit;
> -               }
> -
> -               ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
> -                                                GFP_KERNEL);
> -               if (!ses->auth_key.response) {
> -                       cifs_dbg(VFS,
> -                               "Kerberos can't allocate (%u bytes) memory",
> -                               msg->sesskey_len);
> -                       rc = -ENOMEM;
> -                       goto ssetup_exit;
> -               }
> -               ses->auth_key.len = msg->sesskey_len;
> -
> -               pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
> -               capabilities |= CAP_EXTENDED_SECURITY;
> -               pSMB->req.Capabilities = cpu_to_le32(capabilities);
> -               iov[1].iov_base = msg->data + msg->sesskey_len;
> -               iov[1].iov_len = msg->secblob_len;
> -               pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
> -
> -               if (ses->capabilities & CAP_UNICODE) {
> -                       /* unicode strings must be word aligned */
> -                       if ((iov[0].iov_len + iov[1].iov_len) % 2) {
> -                               *bcc_ptr = 0;
> -                               bcc_ptr++;
> -                       }
> -                       unicode_oslm_strings(&bcc_ptr, nls_cp);
> -                       unicode_domain_string(&bcc_ptr, ses, nls_cp);
> -               } else
> -               /* BB: is this right? */
> -                       ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
> -#else /* ! CONFIG_CIFS_UPCALL */
> -               cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
> -               rc = -ENOSYS;
> -               goto ssetup_exit;
> -#endif /* CONFIG_CIFS_UPCALL */
> -       } else if (type == RawNTLMSSP) {
> +       if (type == RawNTLMSSP) {
>                 if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
>                         cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
>                         rc = -ENOSYS;
> @@ -1268,10 +1363,6 @@ ssetup_ntlmssp_authenticate:
>         }
>
>  ssetup_exit:
> -       if (spnego_key) {
> -               key_invalidate(spnego_key);
> -               key_put(spnego_key);
> -       }
>         kfree(str_area);
>         kfree(ntlmsspblob);
>         ntlmsspblob = NULL;
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 5/5] cifs: Separate rawntlmssp auth from CIFS_SessSetup()

[Shirish Pargaonkar]

Looks good.

Reviewed-by: Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>

On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> Separate rawntlmssp authentication from CIFS_SessSetup(). Also cleanup
> CIFS_SessSetup() since we no longer do any auth within it.
>
> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  fs/cifs/sess.c | 490 +++++++++++++++++++++++++++++++--------------------------
>  1 file changed, 263 insertions(+), 227 deletions(-)
>
> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
> index b413fae..c2e7c07 100644
> --- a/fs/cifs/sess.c
> +++ b/fs/cifs/sess.c
> @@ -1113,241 +1113,225 @@ sess_auth_kerberos(struct sess_data *sess_data)
>  }
>  #endif /* ! CONFIG_CIFS_UPCALL */
>
> -int
> -CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
> -              const struct nls_table *nls_cp)
> +/*
> + * The required kvec buffers have to be allocated before calling this
> + * function.
> + */
> +static int
> +_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
>  {
> -       int rc = 0;
> -       int wct;
>         struct smb_hdr *smb_buf;
> -       char *bcc_ptr;
> -       char *str_area;
>         SESSION_SETUP_ANDX *pSMB;
> +       struct cifs_ses *ses = sess_data->ses;
>         __u32 capabilities;
> -       __u16 count;
> -       int resp_buf_type;
> -       struct kvec iov[3];
> -       enum securityEnum type;
> -       __u16 action, bytes_remaining;
> -       __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
> -       u16 blob_len;
> -       char *ntlmsspblob = NULL;
> -       struct sess_data *sess_data;
> +       char *bcc_ptr;
>
> -       if (ses == NULL) {
> -               WARN(1, "%s: ses == NULL!", __func__);
> -               return -EINVAL;
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)pSMB;
> +
> +       capabilities = cifs_ssetup_hdr(ses, pSMB);
> +       if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
> +               cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
> +               return -ENOSYS;
>         }
>
> -       sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
> -       if (!sess_data)
> -               return -ENOMEM;
> -       sess_data->xid = xid;
> -       sess_data->ses = ses;
> -       sess_data->buf0_type = CIFS_NO_BUFFER;
> -       sess_data->nls_cp = (struct nls_table *) nls_cp;
> +       pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
> +       capabilities |= CAP_EXTENDED_SECURITY;
> +       pSMB->req.Capabilities |= cpu_to_le32(capabilities);
>
> -       type = select_sectype(ses->server, ses->sectype);
> -       cifs_dbg(FYI, "sess setup type %d\n", type);
> -       if (type == Unspecified) {
> -               cifs_dbg(VFS,
> -                       "Unable to select appropriate authentication method!");
> -               return -EINVAL;
> +       bcc_ptr = sess_data->iov[2].iov_base;
> +       /* unicode strings must be word aligned */
> +       if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
> +               *bcc_ptr = 0;
> +               bcc_ptr++;
>         }
> +       unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
>
> -       switch (type) {
> -       case LANMAN:
> -               sess_auth_lanman(sess_data);
> -               goto out;
> -       case NTLM:
> -               sess_auth_ntlm(sess_data);
> -               goto out;
> -       case NTLMv2:
> -               sess_auth_ntlmv2(sess_data);
> -               goto out;
> -       case Kerberos:
> -               sess_auth_kerberos(sess_data);
> -               goto out;
> -       default:
> -               cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
> -       }
> +       sess_data->iov[2].iov_len = (long) bcc_ptr -
> +                                       (long) sess_data->iov[2].iov_base;
>
> -       if (type == RawNTLMSSP) {
> -               /* if memory allocation is successful, caller of this function
> -                * frees it.
> -                */
> -               ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
> -               if (!ses->ntlmssp)
> -                       return -ENOMEM;
> -               ses->ntlmssp->sesskey_per_smbsess = false;
> +       return 0;
> +}
> +
> +static void
> +sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
> +
> +static void
> +sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
> +{
> +       int rc;
> +       struct smb_hdr *smb_buf;
> +       SESSION_SETUP_ANDX *pSMB;
> +       struct cifs_ses *ses = sess_data->ses;
> +       __u16 bytes_remaining;
> +       char *bcc_ptr;
> +       u16 blob_len;
> +
> +       cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
>
> +       /*
> +        * if memory allocation is successful, caller of this function
> +        * frees it.
> +        */
> +       ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
> +       if (!ses->ntlmssp) {
> +               rc = -ENOMEM;
> +               goto out;
>         }
> +       ses->ntlmssp->sesskey_per_smbsess = false;
>
> -ssetup_ntlmssp_authenticate:
> -       if (phase == NtLmChallenge)
> -               phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
> +       /* wct = 12 */
> +       rc = sess_alloc_buffer(sess_data, 12);
> +       if (rc)
> +               goto out;
>
> -       /* same size: negotiate or auth, NTLMSSP or extended security */
> -       wct = 12;
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
>
> -       rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
> -                           (void **)&smb_buf);
> +       /* Build security blob before we assemble the request */
> +       build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses);
> +       sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
> +       sess_data->iov[1].iov_base = pSMB->req.SecurityBlob;
> +       pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
> +
> +       rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
>         if (rc)
> -               return rc;
> +               goto out;
>
> -       pSMB = (SESSION_SETUP_ANDX *)smb_buf;
> +       rc = sess_sendreceive(sess_data);
>
> -       capabilities = cifs_ssetup_hdr(ses, pSMB);
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
>
> -       /* we will send the SMB in three pieces:
> -       a fixed length beginning part, an optional
> -       SPNEGO blob (which can be zero length), and a
> -       last part which will include the strings
> -       and rest of bcc area. This allows us to avoid
> -       a large buffer 17K allocation */
> -       iov[0].iov_base = (char *)pSMB;
> -       iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
> -
> -       /* setting this here allows the code at the end of the function
> -          to free the request buffer if there's an error */
> -       resp_buf_type = CIFS_SMALL_BUFFER;
> +       /* If true, rc here is expected and not an error */
> +       if (sess_data->buf0_type != CIFS_NO_BUFFER &&
> +           smb_buf->Status.CifsError ==
> +                       cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
> +               rc = 0;
>
> -       /* 2000 big enough to fit max user, domain, NOS name etc. */
> -       str_area = kmalloc(2000, GFP_KERNEL);
> -       if (str_area == NULL) {
> -               rc = -ENOMEM;
> -               goto ssetup_exit;
> +       if (rc)
> +               goto out;
> +
> +       cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
> +
> +       if (smb_buf->WordCount != 4) {
> +               rc = -EIO;
> +               cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
> +               goto out;
>         }
> -       bcc_ptr = str_area;
>
> -       iov[1].iov_base = NULL;
> -       iov[1].iov_len = 0;
> +       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
> +       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
>
> -       if (type == RawNTLMSSP) {
> -               if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
> -                       cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
> -                       rc = -ENOSYS;
> -                       goto ssetup_exit;
> -               }
> +       bytes_remaining = get_bcc(smb_buf);
> +       bcc_ptr = pByteArea(smb_buf);
>
> -               cifs_dbg(FYI, "ntlmssp session setup phase %d\n", phase);
> -               pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
> -               capabilities |= CAP_EXTENDED_SECURITY;
> -               pSMB->req.Capabilities |= cpu_to_le32(capabilities);
> -               switch(phase) {
> -               case NtLmNegotiate:
> -                       build_ntlmssp_negotiate_blob(
> -                               pSMB->req.SecurityBlob, ses);
> -                       iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
> -                       iov[1].iov_base = pSMB->req.SecurityBlob;
> -                       pSMB->req.SecurityBlobLength =
> -                               cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
> -                       break;
> -               case NtLmAuthenticate:
> -                       /*
> -                        * 5 is an empirical value, large enough to hold
> -                        * authenticate message plus max 10 of av paris,
> -                        * domain, user, workstation names, flags, etc.
> -                        */
> -                       ntlmsspblob = kzalloc(
> -                               5*sizeof(struct _AUTHENTICATE_MESSAGE),
> -                               GFP_KERNEL);
> -                       if (!ntlmsspblob) {
> -                               rc = -ENOMEM;
> -                               goto ssetup_exit;
> -                       }
> +       blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
> +       if (blob_len > bytes_remaining) {
> +               cifs_dbg(VFS, "bad security blob length %d\n",
> +                               blob_len);
> +               rc = -EINVAL;
> +               goto out;
> +       }
>
> -                       rc = build_ntlmssp_auth_blob(ntlmsspblob,
> -                                               &blob_len, ses, nls_cp);
> -                       if (rc)
> -                               goto ssetup_exit;
> -                       iov[1].iov_len = blob_len;
> -                       iov[1].iov_base = ntlmsspblob;
> -                       pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
> -                       /*
> -                        * Make sure that we tell the server that we are using
> -                        * the uid that it just gave us back on the response
> -                        * (challenge)
> -                        */
> -                       smb_buf->Uid = ses->Suid;
> -                       break;
> -               default:
> -                       cifs_dbg(VFS, "invalid phase %d\n", phase);
> -                       rc = -ENOSYS;
> -                       goto ssetup_exit;
> -               }
> -               /* unicode strings must be word aligned */
> -               if ((iov[0].iov_len + iov[1].iov_len) % 2) {
> -                       *bcc_ptr = 0;
> -                       bcc_ptr++;
> -               }
> -               unicode_oslm_strings(&bcc_ptr, nls_cp);
> -       } else {
> -               cifs_dbg(VFS, "secType %d not supported!\n", type);
> -               rc = -ENOSYS;
> -               goto ssetup_exit;
> +       rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
> +out:
> +       sess_free_buffer(sess_data);
> +
> +       if (!rc) {
> +               sess_data->func = sess_auth_rawntlmssp_authenticate;
> +               return;
>         }
>
> -       iov[2].iov_base = str_area;
> -       iov[2].iov_len = (long) bcc_ptr - (long) str_area;
> +       /* Else error. Cleanup */
> +       kfree(ses->auth_key.response);
> +       ses->auth_key.response = NULL;
> +       kfree(ses->ntlmssp);
> +       ses->ntlmssp = NULL;
>
> -       count = iov[1].iov_len + iov[2].iov_len;
> -       smb_buf->smb_buf_length =
> -               cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
> +       sess_data->func = NULL;
> +       sess_data->result = rc;
> +}
>
> -       put_bcc(count, smb_buf);
> +static void
> +sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
> +{
> +       int rc;
> +       struct smb_hdr *smb_buf;
> +       SESSION_SETUP_ANDX *pSMB;
> +       struct cifs_ses *ses = sess_data->ses;
> +       __u16 bytes_remaining;
> +       char *bcc_ptr;
> +       char *ntlmsspblob = NULL;
> +       u16 blob_len;
>
> -       rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
> -                         CIFS_LOG_ERROR);
> -       /* SMB request buf freed in SendReceive2 */
> +       cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
>
> -       pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
> -       smb_buf = (struct smb_hdr *)iov[0].iov_base;
> +       /* wct = 12 */
> +       rc = sess_alloc_buffer(sess_data, 12);
> +       if (rc)
> +               goto out;
>
> -       if ((type == RawNTLMSSP) && (resp_buf_type != CIFS_NO_BUFFER) &&
> -           (smb_buf->Status.CifsError ==
> -                       cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
> -               if (phase != NtLmNegotiate) {
> -                       cifs_dbg(VFS, "Unexpected more processing error\n");
> -                       goto ssetup_exit;
> -               }
> -               /* NTLMSSP Negotiate sent now processing challenge (response) */
> -               phase = NtLmChallenge; /* process ntlmssp challenge */
> -               rc = 0; /* MORE_PROC rc is not an error here, but expected */
> +       /* Build security blob before we assemble the request */
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)pSMB;
> +       /*
> +        * 5 is an empirical value, large enough to hold
> +        * authenticate message plus max 10 of av paris,
> +        * domain, user, workstation names, flags, etc.
> +        */
> +       ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE),
> +                               GFP_KERNEL);
> +       if (!ntlmsspblob) {
> +               rc = -ENOMEM;
> +               goto out;
>         }
> +
> +       rc = build_ntlmssp_auth_blob(ntlmsspblob,
> +                                       &blob_len, ses, sess_data->nls_cp);
> +       if (rc)
> +               goto out_free_ntlmsspblob;
> +       sess_data->iov[1].iov_len = blob_len;
> +       sess_data->iov[1].iov_base = ntlmsspblob;
> +       pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
> +       /*
> +        * Make sure that we tell the server that we are using
> +        * the uid that it just gave us back on the response
> +        * (challenge)
> +        */
> +       smb_buf->Uid = ses->Suid;
> +
> +       rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
>         if (rc)
> -               goto ssetup_exit;
> +               goto out_free_ntlmsspblob;
>
> +       rc = sess_sendreceive(sess_data);
> +       if (rc)
> +               goto out_free_ntlmsspblob;
> +
> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
>         if (smb_buf->WordCount != 4) {
>                 rc = -EIO;
>                 cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
> -               goto ssetup_exit;
> +               goto out_free_ntlmsspblob;
>         }
> -       action = le16_to_cpu(pSMB->resp.Action);
> -       if (action & GUEST_LOGIN)
> +
> +       if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
>                 cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
> -       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
> -       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
> -       /* response can have either 3 or 4 word count - Samba sends 3 */
> -       /* and lanman response is 3 */
> +
>         bytes_remaining = get_bcc(smb_buf);
>         bcc_ptr = pByteArea(smb_buf);
> -
>         blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
>         if (blob_len > bytes_remaining) {
>                 cifs_dbg(VFS, "bad security blob length %d\n",
> -                        blob_len);
> +                               blob_len);
>                 rc = -EINVAL;
> -               goto ssetup_exit;
> -       }
> -       if (phase == NtLmChallenge) {
> -               rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
> -               if (rc)
> -                       goto ssetup_exit;
> +               goto out_free_ntlmsspblob;
>         }
>         bcc_ptr += blob_len;
>         bytes_remaining -= blob_len;
>
> +
>         /* BB check if Unicode and decode strings */
>         if (bytes_remaining == 0) {
>                 /* no string area to decode, do nothing */
> @@ -1357,61 +1341,113 @@ ssetup_ntlmssp_authenticate:
>                         ++bcc_ptr;
>                         --bytes_remaining;
>                 }
> -               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
> +               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                     sess_data->nls_cp);
>         } else {
> -               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
> +               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
> +                                   sess_data->nls_cp);
>         }
>
> -ssetup_exit:
> -       kfree(str_area);
> +out_free_ntlmsspblob:
>         kfree(ntlmsspblob);
> -       ntlmsspblob = NULL;
> -       if (resp_buf_type == CIFS_SMALL_BUFFER) {
> -               cifs_dbg(FYI, "ssetup freeing small buf %p\n", iov[0].iov_base);
> -               cifs_small_buf_release(iov[0].iov_base);
> -       } else if (resp_buf_type == CIFS_LARGE_BUFFER)
> -               cifs_buf_release(iov[0].iov_base);
> -
> -       /* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
> -       if ((phase == NtLmChallenge) && (rc == 0))
> -               goto ssetup_ntlmssp_authenticate;
> -
> -       if (!rc) {
> -               mutex_lock(&ses->server->srv_mutex);
> -               if (!ses->server->session_estab) {
> -                       if (ses->server->sign) {
> -                               ses->server->session_key.response =
> -                                       kmemdup(ses->auth_key.response,
> -                                       ses->auth_key.len, GFP_KERNEL);
> -                               if (!ses->server->session_key.response) {
> -                                       rc = -ENOMEM;
> -                                       mutex_unlock(&ses->server->srv_mutex);
> -                                       goto keycp_exit;
> -                               }
> -                               ses->server->session_key.len =
> -                                                       ses->auth_key.len;
> -                       }
> -                       ses->server->sequence_number = 0x2;
> -                       ses->server->session_estab = true;
> -               }
> -               mutex_unlock(&ses->server->srv_mutex);
> +out:
> +       sess_free_buffer(sess_data);
>
> -               cifs_dbg(FYI, "CIFS session established successfully\n");
> -               spin_lock(&GlobalMid_Lock);
> -               ses->status = CifsGood;
> -               ses->need_reconnect = false;
> -               spin_unlock(&GlobalMid_Lock);
> -       }
> +        if (!rc)
> +               rc = sess_establish_session(sess_data);
>
> -keycp_exit:
> +       /* Cleanup */
>         kfree(ses->auth_key.response);
>         ses->auth_key.response = NULL;
>         kfree(ses->ntlmssp);
> +       ses->ntlmssp = NULL;
>
> -       return rc;
> +       sess_data->func = NULL;
> +       sess_data->result = rc;
> +}
>
> -out:
> +int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
> +{
> +       int type;
> +
> +       type = select_sectype(ses->server, ses->sectype);
> +       cifs_dbg(FYI, "sess setup type %d\n", type);
> +       if (type == Unspecified) {
> +               cifs_dbg(VFS,
> +                       "Unable to select appropriate authentication method!");
> +               return -EINVAL;
> +       }
> +
> +       switch (type) {
> +       case LANMAN:
> +               /* LANMAN and plaintext are less secure and off by default.
> +                * So we make this explicitly be turned on in kconfig (in the
> +                * build) and turned on at runtime (changed from the default)
> +                * in proc/fs/cifs or via mount parm.  Unfortunately this is
> +                * needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
> +#ifdef CONFIG_CIFS_WEAK_PW_HASH
> +               sess_data->func = sess_auth_lanman;
> +               break;
> +#else
> +               return -EOPNOTSUPP;
> +#endif
> +       case NTLM:
> +               sess_data->func = sess_auth_ntlm;
> +               break;
> +       case NTLMv2:
> +               sess_data->func = sess_auth_ntlmv2;
> +               break;
> +       case Kerberos:
> +#ifdef CONFIG_CIFS_UPCALL
> +               sess_data->func = sess_auth_kerberos;
> +               break;
> +#else
> +               cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
> +               return -ENOSYS;
> +               break;
> +#endif /* CONFIG_CIFS_UPCALL */
> +       case RawNTLMSSP:
> +               sess_data->func = sess_auth_rawntlmssp_negotiate;
> +               break;
> +       default:
> +               cifs_dbg(VFS, "secType %d not supported!\n", type);
> +               return -ENOSYS;
> +       }
> +
> +       return 0;
> +}
> +
> +int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
> +                   const struct nls_table *nls_cp)
> +{
> +       int rc = 0;
> +       struct sess_data *sess_data;
> +
> +       if (ses == NULL) {
> +               WARN(1, "%s: ses == NULL!", __func__);
> +               return -EINVAL;
> +       }
> +
> +       sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
> +       if (!sess_data)
> +               return -ENOMEM;
> +
> +       rc = select_sec(ses, sess_data);
> +       if (rc)
> +               goto out;
> +
> +       sess_data->xid = xid;
> +       sess_data->ses = ses;
> +       sess_data->buf0_type = CIFS_NO_BUFFER;
> +       sess_data->nls_cp = (struct nls_table *) nls_cp;
> +
> +       while (sess_data->func)
> +               sess_data->func(sess_data);
> +
> +       /* Store result before we free sess_data */
>         rc = sess_data->result;
> +
> +out:
>         kfree(sess_data);
>         return rc;
>  }
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 0/5 v4] Split CIFS_SessSetup()

[Steve French]

FYI - Two trivial checkpatch warnings.  Any obvious way to get rid of
at least the first warning?

WARNING: Missing a blank line after declarations
#30: FILE: fs/cifs/sess.c:527:
+    struct nls_table *nls_cp;
+    void (*func)(struct sess_data *);

total: 0 errors, 1 warnings, 349 lines checked

0002-cifs-Split-lanman-auth-from-CIFS_SessSetup.patch has style
problems, please review.


WARNING: Prefer kcalloc over kzalloc with multiply
#358: FILE: fs/cifs/sess.c:1282:
+    ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE),

total: 0 errors, 1 warnings, 565 lines checked

0005-cifs-Separate-rawntlmssp-auth-from-CIFS_SessSetup.patch has style
problems, please review.

On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> I am investigating the possibility of adding support for gss-proxy in the
> cifs client module. As part of that investigation, I was looking at the
> CIFS_SessSetup() function. This is a long function which handles multiple auths
> using if conditions and switch statements. The code struction makes it
> difficult to modify or add support for new authentication mechanisms.
>
> The proposal is to split the various authentication code into its own separate
> functions. This increases the lines of code but will simplify maintenance and
> addition of new auth methods.
>
> The short term goal is to add gss-proxy support for kerberos authentication.
> This will require to and fro communication with the gss-proxy module over a
> unix socket.
>
> Further long term goals are
> 1) Add support for NTLMSSP using SPNEGO,
> 2) Allow clients to negotiate which authentication mechanism to use using SPNEGO.
>
> V2:
> - Ensure that sess_data allocated on intermediate patches are freed.
> - Remove ifdef-endif blocks from the switch statement in CIFS_SessSetup().
>
> V3:
> - Fix whitespace errors in some patches.
> - Change sess_establish_session to return errors. Call this function only in
>   case of successful establish session calls to the server.
> - Delete an incorrect comment in case of rawntlmssp authentication.
> - Delete an if statement before kfree(ntlmssp) in rawntlmssp authentication.
>
> v4:
> - reordered elements of struct sess_data as asked by jlayton
> - Use free_rsp_buf() to clean buffer.
> - Clean up the rawntlmssp case further and break the calls into separate
>   functions.
>
> Sachin Prabhu (5):
>   cifs: replace code with free_rsp_buf()
>   cifs: Split lanman auth from CIFS_SessSetup()
>   cifs: Split ntlm and ntlmv2 authentication methods off
>     CIFS_SessSetup()
>   cifs: Split Kerberos authentication off CIFS_SessSetup()
>   cifs: Separate rawntlmssp auth from CIFS_SessSetup()
>
>  fs/cifs/cifsproto.h |    1 +
>  fs/cifs/cifssmb.c   |   20 +-
>  fs/cifs/misc.c      |    9 +
>  fs/cifs/sess.c      | 1192 ++++++++++++++++++++++++++++++++++++---------------
>  fs/cifs/smb2pdu.c   |   10 -
>  5 files changed, 854 insertions(+), 378 deletions(-)
>
> --
> 1.9.3
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Thanks,

Steve

Re: [PATCH 1/5] cifs: replace code with free_rsp_buf()

[Steve French]

merged into cifs-2.6.git

nice little cleanup

On Tue, Jun 17, 2014 at 11:33 PM, Shirish Pargaonkar
<shirishpargaonkar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Looks correct.
>
> Reviewed-by: Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>
>
> On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
>> The functionality provided by free_rsp_buf() is duplicated in a number
>> of places. Replace these instances with a call to free_rsp_buf().
>>
>> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
>> ---
>>  fs/cifs/cifsproto.h |  1 +
>>  fs/cifs/cifssmb.c   | 20 ++++----------------
>>  fs/cifs/misc.c      |  9 +++++++++
>>  fs/cifs/smb2pdu.c   | 10 ----------
>>  4 files changed, 14 insertions(+), 26 deletions(-)
>>
>> diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
>> index ca7980a..de49d7a 100644
>> --- a/fs/cifs/cifsproto.h
>> +++ b/fs/cifs/cifsproto.h
>> @@ -36,6 +36,7 @@ extern struct smb_hdr *cifs_buf_get(void);
>>  extern void cifs_buf_release(void *);
>>  extern struct smb_hdr *cifs_small_buf_get(void);
>>  extern void cifs_small_buf_release(void *);
>> +extern void free_rsp_buf(int, void *);
>>  extern void cifs_rqst_page_to_kvec(struct smb_rqst *rqst, unsigned int idx,
>>                                         struct kvec *iov);
>>  extern int smb_send(struct TCP_Server_Info *, struct smb_hdr *,
>> diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
>> index 6ce4e09..b7e5b65 100644
>> --- a/fs/cifs/cifssmb.c
>> +++ b/fs/cifs/cifssmb.c
>> @@ -1734,10 +1734,7 @@ CIFSSMBRead(const unsigned int xid, struct cifs_io_parms *io_parms,
>>
>>  /*     cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
>>         if (*buf) {
>> -               if (resp_buf_type == CIFS_SMALL_BUFFER)
>> -                       cifs_small_buf_release(iov[0].iov_base);
>> -               else if (resp_buf_type == CIFS_LARGE_BUFFER)
>> -                       cifs_buf_release(iov[0].iov_base);
>> +               free_rsp_buf(resp_buf_type, iov[0].iov_base);
>>         } else if (resp_buf_type != CIFS_NO_BUFFER) {
>>                 /* return buffer to caller to free */
>>                 *buf = iov[0].iov_base;
>> @@ -2203,10 +2200,7 @@ CIFSSMBWrite2(const unsigned int xid, struct cifs_io_parms *io_parms,
>>         }
>>
>>  /*     cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
>> -       if (resp_buf_type == CIFS_SMALL_BUFFER)
>> -               cifs_small_buf_release(iov[0].iov_base);
>> -       else if (resp_buf_type == CIFS_LARGE_BUFFER)
>> -               cifs_buf_release(iov[0].iov_base);
>> +       free_rsp_buf(resp_buf_type, iov[0].iov_base);
>>
>>         /* Note: On -EAGAIN error only caller can retry on handle based calls
>>                 since file handle passed in no longer valid */
>> @@ -2451,10 +2445,7 @@ plk_err_exit:
>>         if (pSMB)
>>                 cifs_small_buf_release(pSMB);
>>
>> -       if (resp_buf_type == CIFS_SMALL_BUFFER)
>> -               cifs_small_buf_release(iov[0].iov_base);
>> -       else if (resp_buf_type == CIFS_LARGE_BUFFER)
>> -               cifs_buf_release(iov[0].iov_base);
>> +       free_rsp_buf(resp_buf_type, iov[0].iov_base);
>>
>>         /* Note: On -EAGAIN error only caller can retry on handle based calls
>>            since file handle passed in no longer valid */
>> @@ -3838,10 +3829,7 @@ CIFSSMBGetCIFSACL(const unsigned int xid, struct cifs_tcon *tcon, __u16 fid,
>>                 }
>>         }
>>  qsec_out:
>> -       if (buf_type == CIFS_SMALL_BUFFER)
>> -               cifs_small_buf_release(iov[0].iov_base);
>> -       else if (buf_type == CIFS_LARGE_BUFFER)
>> -               cifs_buf_release(iov[0].iov_base);
>> +       free_rsp_buf(buf_type, iov[0].iov_base);
>>  /*     cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
>>         return rc;
>>  }
>> diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
>> index 3b0c62e..64997a0 100644
>> --- a/fs/cifs/misc.c
>> +++ b/fs/cifs/misc.c
>> @@ -226,6 +226,15 @@ cifs_small_buf_release(void *buf_to_free)
>>         return;
>>  }
>>
>> +void
>> +free_rsp_buf(int resp_buftype, void *rsp)
>> +{
>> +       if (resp_buftype == CIFS_SMALL_BUFFER)
>> +               cifs_small_buf_release(rsp);
>> +       else if (resp_buftype == CIFS_LARGE_BUFFER)
>> +               cifs_buf_release(rsp);
>> +}
>> +
>>  /* NB: MID can not be set if treeCon not passed in, in that
>>     case it is responsbility of caller to set the mid */
>>  void
>> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
>> index b0b260d..0158104 100644
>> --- a/fs/cifs/smb2pdu.c
>> +++ b/fs/cifs/smb2pdu.c
>> @@ -309,16 +309,6 @@ small_smb2_init(__le16 smb2_command, struct cifs_tcon *tcon,
>>         return rc;
>>  }
>>
>> -static void
>> -free_rsp_buf(int resp_buftype, void *rsp)
>> -{
>> -       if (resp_buftype == CIFS_SMALL_BUFFER)
>> -               cifs_small_buf_release(rsp);
>> -       else if (resp_buftype == CIFS_LARGE_BUFFER)
>> -               cifs_buf_release(rsp);
>> -}
>> -
>> -
>>  /*
>>   *
>>   *     SMB2 Worker functions follow:
>> --
>> 1.9.3
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
>> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Thanks,

Steve

Re: [PATCH 0/5 v4] Split CIFS_SessSetup()

[Sachin Prabhu]

Hello Steve,

I thought I had put those through the checkpatch.pl script before
sending them upstream. I guess I was mistaken.

On Thu, 2014-06-26 at 01:11 -0500, Steve French wrote:
> FYI - Two trivial checkpatch warnings.  Any obvious way to get rid of
> at least the first warning?
> 
> WARNING: Missing a blank line after declarations
> #30: FILE: fs/cifs/sess.c:527:
> +    struct nls_table *nls_cp;
> +    void (*func)(struct sess_data *);
> 
> total: 0 errors, 1 warnings, 349 lines checked
> 
> 0002-cifs-Split-lanman-auth-from-CIFS_SessSetup.patch has style
> problems, please review.

This seems to be a false positive where it incorrectly thinks that the
function pointer is not part of the declarations. if I add a blank line
between the 2 lines above, it no longer shows that warning.

> 
> 
> WARNING: Prefer kcalloc over kzalloc with multiply
> #358: FILE: fs/cifs/sess.c:1282:
> +    ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE),
> 
> total: 0 errors, 1 warnings, 565 lines checked
> 
> 0005-cifs-Separate-rawntlmssp-auth-from-CIFS_SessSetup.patch has style
> problems, please review.

This was simply copied from the original code.

Sachin Prabhu

> 
> On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> > I am investigating the possibility of adding support for gss-proxy in the
> > cifs client module. As part of that investigation, I was looking at the
> > CIFS_SessSetup() function. This is a long function which handles multiple auths
> > using if conditions and switch statements. The code struction makes it
> > difficult to modify or add support for new authentication mechanisms.
> >
> > The proposal is to split the various authentication code into its own separate
> > functions. This increases the lines of code but will simplify maintenance and
> > addition of new auth methods.
> >
> > The short term goal is to add gss-proxy support for kerberos authentication.
> > This will require to and fro communication with the gss-proxy module over a
> > unix socket.
> >
> > Further long term goals are
> > 1) Add support for NTLMSSP using SPNEGO,
> > 2) Allow clients to negotiate which authentication mechanism to use using SPNEGO.
> >
> > V2:
> > - Ensure that sess_data allocated on intermediate patches are freed.
> > - Remove ifdef-endif blocks from the switch statement in CIFS_SessSetup().
> >
> > V3:
> > - Fix whitespace errors in some patches.
> > - Change sess_establish_session to return errors. Call this function only in
> >   case of successful establish session calls to the server.
> > - Delete an incorrect comment in case of rawntlmssp authentication.
> > - Delete an if statement before kfree(ntlmssp) in rawntlmssp authentication.
> >
> > v4:
> > - reordered elements of struct sess_data as asked by jlayton
> > - Use free_rsp_buf() to clean buffer.
> > - Clean up the rawntlmssp case further and break the calls into separate
> >   functions.
> >
> > Sachin Prabhu (5):
> >   cifs: replace code with free_rsp_buf()
> >   cifs: Split lanman auth from CIFS_SessSetup()
> >   cifs: Split ntlm and ntlmv2 authentication methods off
> >     CIFS_SessSetup()
> >   cifs: Split Kerberos authentication off CIFS_SessSetup()
> >   cifs: Separate rawntlmssp auth from CIFS_SessSetup()
> >
> >  fs/cifs/cifsproto.h |    1 +
> >  fs/cifs/cifssmb.c   |   20 +-
> >  fs/cifs/misc.c      |    9 +
> >  fs/cifs/sess.c      | 1192 ++++++++++++++++++++++++++++++++++++---------------
> >  fs/cifs/smb2pdu.c   |   10 -
> >  5 files changed, 854 insertions(+), 378 deletions(-)
> >
> > --
> > 1.9.3
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
> > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 
> 

Re: [PATCH 5/5] cifs: Separate rawntlmssp auth from CIFS_SessSetup()

[Steve French]

Added trivial patch to fix sparse build warning

From: Steve French <smfrench-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Date: Fri, 11 Jul 2014 07:47:01 -0500
Subject: [PATCH] [CIFS] Remove sparse build warning

The recent session setup patch set
(cifs-Separate-rawntlmssp-auth-from-CIFS_SessSetup.patch)
had introduced a trivial sparse build warning.

Signed-off-by: Steve French <smfrench-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 fs/cifs/sess.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index c2e7c07..39ee326 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -1366,7 +1366,7 @@ out:
     sess_data->result = rc;
 }

-int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
+static int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
 {
     int type;


On Mon, Jun 23, 2014 at 10:33 PM, Shirish Pargaonkar
<shirishpargaonkar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Looks good.
>
> Reviewed-by: Shirish Pargaonkar <spargaonkar-IBi9RG/b67k@public.gmane.org>
>
> On Mon, Jun 16, 2014 at 9:35 AM, Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
>> Separate rawntlmssp authentication from CIFS_SessSetup(). Also cleanup
>> CIFS_SessSetup() since we no longer do any auth within it.
>>
>> Signed-off-by: Sachin Prabhu <sprabhu-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
>> ---
>>  fs/cifs/sess.c | 490 +++++++++++++++++++++++++++++++--------------------------
>>  1 file changed, 263 insertions(+), 227 deletions(-)
>>
>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>> index b413fae..c2e7c07 100644
>> --- a/fs/cifs/sess.c
>> +++ b/fs/cifs/sess.c
>> @@ -1113,241 +1113,225 @@ sess_auth_kerberos(struct sess_data *sess_data)
>>  }
>>  #endif /* ! CONFIG_CIFS_UPCALL */
>>
>> -int
>> -CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>> -              const struct nls_table *nls_cp)
>> +/*
>> + * The required kvec buffers have to be allocated before calling this
>> + * function.
>> + */
>> +static int
>> +_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
>>  {
>> -       int rc = 0;
>> -       int wct;
>>         struct smb_hdr *smb_buf;
>> -       char *bcc_ptr;
>> -       char *str_area;
>>         SESSION_SETUP_ANDX *pSMB;
>> +       struct cifs_ses *ses = sess_data->ses;
>>         __u32 capabilities;
>> -       __u16 count;
>> -       int resp_buf_type;
>> -       struct kvec iov[3];
>> -       enum securityEnum type;
>> -       __u16 action, bytes_remaining;
>> -       __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
>> -       u16 blob_len;
>> -       char *ntlmsspblob = NULL;
>> -       struct sess_data *sess_data;
>> +       char *bcc_ptr;
>>
>> -       if (ses == NULL) {
>> -               WARN(1, "%s: ses == NULL!", __func__);
>> -               return -EINVAL;
>> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
>> +       smb_buf = (struct smb_hdr *)pSMB;
>> +
>> +       capabilities = cifs_ssetup_hdr(ses, pSMB);
>> +       if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
>> +               cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
>> +               return -ENOSYS;
>>         }
>>
>> -       sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
>> -       if (!sess_data)
>> -               return -ENOMEM;
>> -       sess_data->xid = xid;
>> -       sess_data->ses = ses;
>> -       sess_data->buf0_type = CIFS_NO_BUFFER;
>> -       sess_data->nls_cp = (struct nls_table *) nls_cp;
>> +       pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
>> +       capabilities |= CAP_EXTENDED_SECURITY;
>> +       pSMB->req.Capabilities |= cpu_to_le32(capabilities);
>>
>> -       type = select_sectype(ses->server, ses->sectype);
>> -       cifs_dbg(FYI, "sess setup type %d\n", type);
>> -       if (type == Unspecified) {
>> -               cifs_dbg(VFS,
>> -                       "Unable to select appropriate authentication method!");
>> -               return -EINVAL;
>> +       bcc_ptr = sess_data->iov[2].iov_base;
>> +       /* unicode strings must be word aligned */
>> +       if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
>> +               *bcc_ptr = 0;
>> +               bcc_ptr++;
>>         }
>> +       unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
>>
>> -       switch (type) {
>> -       case LANMAN:
>> -               sess_auth_lanman(sess_data);
>> -               goto out;
>> -       case NTLM:
>> -               sess_auth_ntlm(sess_data);
>> -               goto out;
>> -       case NTLMv2:
>> -               sess_auth_ntlmv2(sess_data);
>> -               goto out;
>> -       case Kerberos:
>> -               sess_auth_kerberos(sess_data);
>> -               goto out;
>> -       default:
>> -               cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
>> -       }
>> +       sess_data->iov[2].iov_len = (long) bcc_ptr -
>> +                                       (long) sess_data->iov[2].iov_base;
>>
>> -       if (type == RawNTLMSSP) {
>> -               /* if memory allocation is successful, caller of this function
>> -                * frees it.
>> -                */
>> -               ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
>> -               if (!ses->ntlmssp)
>> -                       return -ENOMEM;
>> -               ses->ntlmssp->sesskey_per_smbsess = false;
>> +       return 0;
>> +}
>> +
>> +static void
>> +sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
>> +
>> +static void
>> +sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
>> +{
>> +       int rc;
>> +       struct smb_hdr *smb_buf;
>> +       SESSION_SETUP_ANDX *pSMB;
>> +       struct cifs_ses *ses = sess_data->ses;
>> +       __u16 bytes_remaining;
>> +       char *bcc_ptr;
>> +       u16 blob_len;
>> +
>> +       cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
>>
>> +       /*
>> +        * if memory allocation is successful, caller of this function
>> +        * frees it.
>> +        */
>> +       ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
>> +       if (!ses->ntlmssp) {
>> +               rc = -ENOMEM;
>> +               goto out;
>>         }
>> +       ses->ntlmssp->sesskey_per_smbsess = false;
>>
>> -ssetup_ntlmssp_authenticate:
>> -       if (phase == NtLmChallenge)
>> -               phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
>> +       /* wct = 12 */
>> +       rc = sess_alloc_buffer(sess_data, 12);
>> +       if (rc)
>> +               goto out;
>>
>> -       /* same size: negotiate or auth, NTLMSSP or extended security */
>> -       wct = 12;
>> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
>>
>> -       rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
>> -                           (void **)&smb_buf);
>> +       /* Build security blob before we assemble the request */
>> +       build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses);
>> +       sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
>> +       sess_data->iov[1].iov_base = pSMB->req.SecurityBlob;
>> +       pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
>> +
>> +       rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
>>         if (rc)
>> -               return rc;
>> +               goto out;
>>
>> -       pSMB = (SESSION_SETUP_ANDX *)smb_buf;
>> +       rc = sess_sendreceive(sess_data);
>>
>> -       capabilities = cifs_ssetup_hdr(ses, pSMB);
>> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
>> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
>>
>> -       /* we will send the SMB in three pieces:
>> -       a fixed length beginning part, an optional
>> -       SPNEGO blob (which can be zero length), and a
>> -       last part which will include the strings
>> -       and rest of bcc area. This allows us to avoid
>> -       a large buffer 17K allocation */
>> -       iov[0].iov_base = (char *)pSMB;
>> -       iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
>> -
>> -       /* setting this here allows the code at the end of the function
>> -          to free the request buffer if there's an error */
>> -       resp_buf_type = CIFS_SMALL_BUFFER;
>> +       /* If true, rc here is expected and not an error */
>> +       if (sess_data->buf0_type != CIFS_NO_BUFFER &&
>> +           smb_buf->Status.CifsError ==
>> +                       cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
>> +               rc = 0;
>>
>> -       /* 2000 big enough to fit max user, domain, NOS name etc. */
>> -       str_area = kmalloc(2000, GFP_KERNEL);
>> -       if (str_area == NULL) {
>> -               rc = -ENOMEM;
>> -               goto ssetup_exit;
>> +       if (rc)
>> +               goto out;
>> +
>> +       cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
>> +
>> +       if (smb_buf->WordCount != 4) {
>> +               rc = -EIO;
>> +               cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
>> +               goto out;
>>         }
>> -       bcc_ptr = str_area;
>>
>> -       iov[1].iov_base = NULL;
>> -       iov[1].iov_len = 0;
>> +       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
>> +       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
>>
>> -       if (type == RawNTLMSSP) {
>> -               if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
>> -                       cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
>> -                       rc = -ENOSYS;
>> -                       goto ssetup_exit;
>> -               }
>> +       bytes_remaining = get_bcc(smb_buf);
>> +       bcc_ptr = pByteArea(smb_buf);
>>
>> -               cifs_dbg(FYI, "ntlmssp session setup phase %d\n", phase);
>> -               pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
>> -               capabilities |= CAP_EXTENDED_SECURITY;
>> -               pSMB->req.Capabilities |= cpu_to_le32(capabilities);
>> -               switch(phase) {
>> -               case NtLmNegotiate:
>> -                       build_ntlmssp_negotiate_blob(
>> -                               pSMB->req.SecurityBlob, ses);
>> -                       iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
>> -                       iov[1].iov_base = pSMB->req.SecurityBlob;
>> -                       pSMB->req.SecurityBlobLength =
>> -                               cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
>> -                       break;
>> -               case NtLmAuthenticate:
>> -                       /*
>> -                        * 5 is an empirical value, large enough to hold
>> -                        * authenticate message plus max 10 of av paris,
>> -                        * domain, user, workstation names, flags, etc.
>> -                        */
>> -                       ntlmsspblob = kzalloc(
>> -                               5*sizeof(struct _AUTHENTICATE_MESSAGE),
>> -                               GFP_KERNEL);
>> -                       if (!ntlmsspblob) {
>> -                               rc = -ENOMEM;
>> -                               goto ssetup_exit;
>> -                       }
>> +       blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
>> +       if (blob_len > bytes_remaining) {
>> +               cifs_dbg(VFS, "bad security blob length %d\n",
>> +                               blob_len);
>> +               rc = -EINVAL;
>> +               goto out;
>> +       }
>>
>> -                       rc = build_ntlmssp_auth_blob(ntlmsspblob,
>> -                                               &blob_len, ses, nls_cp);
>> -                       if (rc)
>> -                               goto ssetup_exit;
>> -                       iov[1].iov_len = blob_len;
>> -                       iov[1].iov_base = ntlmsspblob;
>> -                       pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
>> -                       /*
>> -                        * Make sure that we tell the server that we are using
>> -                        * the uid that it just gave us back on the response
>> -                        * (challenge)
>> -                        */
>> -                       smb_buf->Uid = ses->Suid;
>> -                       break;
>> -               default:
>> -                       cifs_dbg(VFS, "invalid phase %d\n", phase);
>> -                       rc = -ENOSYS;
>> -                       goto ssetup_exit;
>> -               }
>> -               /* unicode strings must be word aligned */
>> -               if ((iov[0].iov_len + iov[1].iov_len) % 2) {
>> -                       *bcc_ptr = 0;
>> -                       bcc_ptr++;
>> -               }
>> -               unicode_oslm_strings(&bcc_ptr, nls_cp);
>> -       } else {
>> -               cifs_dbg(VFS, "secType %d not supported!\n", type);
>> -               rc = -ENOSYS;
>> -               goto ssetup_exit;
>> +       rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
>> +out:
>> +       sess_free_buffer(sess_data);
>> +
>> +       if (!rc) {
>> +               sess_data->func = sess_auth_rawntlmssp_authenticate;
>> +               return;
>>         }
>>
>> -       iov[2].iov_base = str_area;
>> -       iov[2].iov_len = (long) bcc_ptr - (long) str_area;
>> +       /* Else error. Cleanup */
>> +       kfree(ses->auth_key.response);
>> +       ses->auth_key.response = NULL;
>> +       kfree(ses->ntlmssp);
>> +       ses->ntlmssp = NULL;
>>
>> -       count = iov[1].iov_len + iov[2].iov_len;
>> -       smb_buf->smb_buf_length =
>> -               cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
>> +       sess_data->func = NULL;
>> +       sess_data->result = rc;
>> +}
>>
>> -       put_bcc(count, smb_buf);
>> +static void
>> +sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
>> +{
>> +       int rc;
>> +       struct smb_hdr *smb_buf;
>> +       SESSION_SETUP_ANDX *pSMB;
>> +       struct cifs_ses *ses = sess_data->ses;
>> +       __u16 bytes_remaining;
>> +       char *bcc_ptr;
>> +       char *ntlmsspblob = NULL;
>> +       u16 blob_len;
>>
>> -       rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
>> -                         CIFS_LOG_ERROR);
>> -       /* SMB request buf freed in SendReceive2 */
>> +       cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
>>
>> -       pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
>> -       smb_buf = (struct smb_hdr *)iov[0].iov_base;
>> +       /* wct = 12 */
>> +       rc = sess_alloc_buffer(sess_data, 12);
>> +       if (rc)
>> +               goto out;
>>
>> -       if ((type == RawNTLMSSP) && (resp_buf_type != CIFS_NO_BUFFER) &&
>> -           (smb_buf->Status.CifsError ==
>> -                       cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
>> -               if (phase != NtLmNegotiate) {
>> -                       cifs_dbg(VFS, "Unexpected more processing error\n");
>> -                       goto ssetup_exit;
>> -               }
>> -               /* NTLMSSP Negotiate sent now processing challenge (response) */
>> -               phase = NtLmChallenge; /* process ntlmssp challenge */
>> -               rc = 0; /* MORE_PROC rc is not an error here, but expected */
>> +       /* Build security blob before we assemble the request */
>> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
>> +       smb_buf = (struct smb_hdr *)pSMB;
>> +       /*
>> +        * 5 is an empirical value, large enough to hold
>> +        * authenticate message plus max 10 of av paris,
>> +        * domain, user, workstation names, flags, etc.
>> +        */
>> +       ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE),
>> +                               GFP_KERNEL);
>> +       if (!ntlmsspblob) {
>> +               rc = -ENOMEM;
>> +               goto out;
>>         }
>> +
>> +       rc = build_ntlmssp_auth_blob(ntlmsspblob,
>> +                                       &blob_len, ses, sess_data->nls_cp);
>> +       if (rc)
>> +               goto out_free_ntlmsspblob;
>> +       sess_data->iov[1].iov_len = blob_len;
>> +       sess_data->iov[1].iov_base = ntlmsspblob;
>> +       pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
>> +       /*
>> +        * Make sure that we tell the server that we are using
>> +        * the uid that it just gave us back on the response
>> +        * (challenge)
>> +        */
>> +       smb_buf->Uid = ses->Suid;
>> +
>> +       rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
>>         if (rc)
>> -               goto ssetup_exit;
>> +               goto out_free_ntlmsspblob;
>>
>> +       rc = sess_sendreceive(sess_data);
>> +       if (rc)
>> +               goto out_free_ntlmsspblob;
>> +
>> +       pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
>> +       smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
>>         if (smb_buf->WordCount != 4) {
>>                 rc = -EIO;
>>                 cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
>> -               goto ssetup_exit;
>> +               goto out_free_ntlmsspblob;
>>         }
>> -       action = le16_to_cpu(pSMB->resp.Action);
>> -       if (action & GUEST_LOGIN)
>> +
>> +       if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
>>                 cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
>> -       ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
>> -       cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
>> -       /* response can have either 3 or 4 word count - Samba sends 3 */
>> -       /* and lanman response is 3 */
>> +
>>         bytes_remaining = get_bcc(smb_buf);
>>         bcc_ptr = pByteArea(smb_buf);
>> -
>>         blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
>>         if (blob_len > bytes_remaining) {
>>                 cifs_dbg(VFS, "bad security blob length %d\n",
>> -                        blob_len);
>> +                               blob_len);
>>                 rc = -EINVAL;
>> -               goto ssetup_exit;
>> -       }
>> -       if (phase == NtLmChallenge) {
>> -               rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
>> -               if (rc)
>> -                       goto ssetup_exit;
>> +               goto out_free_ntlmsspblob;
>>         }
>>         bcc_ptr += blob_len;
>>         bytes_remaining -= blob_len;
>>
>> +
>>         /* BB check if Unicode and decode strings */
>>         if (bytes_remaining == 0) {
>>                 /* no string area to decode, do nothing */
>> @@ -1357,61 +1341,113 @@ ssetup_ntlmssp_authenticate:
>>                         ++bcc_ptr;
>>                         --bytes_remaining;
>>                 }
>> -               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
>> +               decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
>> +                                     sess_data->nls_cp);
>>         } else {
>> -               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
>> +               decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
>> +                                   sess_data->nls_cp);
>>         }
>>
>> -ssetup_exit:
>> -       kfree(str_area);
>> +out_free_ntlmsspblob:
>>         kfree(ntlmsspblob);
>> -       ntlmsspblob = NULL;
>> -       if (resp_buf_type == CIFS_SMALL_BUFFER) {
>> -               cifs_dbg(FYI, "ssetup freeing small buf %p\n", iov[0].iov_base);
>> -               cifs_small_buf_release(iov[0].iov_base);
>> -       } else if (resp_buf_type == CIFS_LARGE_BUFFER)
>> -               cifs_buf_release(iov[0].iov_base);
>> -
>> -       /* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
>> -       if ((phase == NtLmChallenge) && (rc == 0))
>> -               goto ssetup_ntlmssp_authenticate;
>> -
>> -       if (!rc) {
>> -               mutex_lock(&ses->server->srv_mutex);
>> -               if (!ses->server->session_estab) {
>> -                       if (ses->server->sign) {
>> -                               ses->server->session_key.response =
>> -                                       kmemdup(ses->auth_key.response,
>> -                                       ses->auth_key.len, GFP_KERNEL);
>> -                               if (!ses->server->session_key.response) {
>> -                                       rc = -ENOMEM;
>> -                                       mutex_unlock(&ses->server->srv_mutex);
>> -                                       goto keycp_exit;
>> -                               }
>> -                               ses->server->session_key.len =
>> -                                                       ses->auth_key.len;
>> -                       }
>> -                       ses->server->sequence_number = 0x2;
>> -                       ses->server->session_estab = true;
>> -               }
>> -               mutex_unlock(&ses->server->srv_mutex);
>> +out:
>> +       sess_free_buffer(sess_data);
>>
>> -               cifs_dbg(FYI, "CIFS session established successfully\n");
>> -               spin_lock(&GlobalMid_Lock);
>> -               ses->status = CifsGood;
>> -               ses->need_reconnect = false;
>> -               spin_unlock(&GlobalMid_Lock);
>> -       }
>> +        if (!rc)
>> +               rc = sess_establish_session(sess_data);
>>
>> -keycp_exit:
>> +       /* Cleanup */
>>         kfree(ses->auth_key.response);
>>         ses->auth_key.response = NULL;
>>         kfree(ses->ntlmssp);
>> +       ses->ntlmssp = NULL;
>>
>> -       return rc;
>> +       sess_data->func = NULL;
>> +       sess_data->result = rc;
>> +}
>>
>> -out:
>> +int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
>> +{
>> +       int type;
>> +
>> +       type = select_sectype(ses->server, ses->sectype);
>> +       cifs_dbg(FYI, "sess setup type %d\n", type);
>> +       if (type == Unspecified) {
>> +               cifs_dbg(VFS,
>> +                       "Unable to select appropriate authentication method!");
>> +               return -EINVAL;
>> +       }
>> +
>> +       switch (type) {
>> +       case LANMAN:
>> +               /* LANMAN and plaintext are less secure and off by default.
>> +                * So we make this explicitly be turned on in kconfig (in the
>> +                * build) and turned on at runtime (changed from the default)
>> +                * in proc/fs/cifs or via mount parm.  Unfortunately this is
>> +                * needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
>> +#ifdef CONFIG_CIFS_WEAK_PW_HASH
>> +               sess_data->func = sess_auth_lanman;
>> +               break;
>> +#else
>> +               return -EOPNOTSUPP;
>> +#endif
>> +       case NTLM:
>> +               sess_data->func = sess_auth_ntlm;
>> +               break;
>> +       case NTLMv2:
>> +               sess_data->func = sess_auth_ntlmv2;
>> +               break;
>> +       case Kerberos:
>> +#ifdef CONFIG_CIFS_UPCALL
>> +               sess_data->func = sess_auth_kerberos;
>> +               break;
>> +#else
>> +               cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
>> +               return -ENOSYS;
>> +               break;
>> +#endif /* CONFIG_CIFS_UPCALL */
>> +       case RawNTLMSSP:
>> +               sess_data->func = sess_auth_rawntlmssp_negotiate;
>> +               break;
>> +       default:
>> +               cifs_dbg(VFS, "secType %d not supported!\n", type);
>> +               return -ENOSYS;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
>> +                   const struct nls_table *nls_cp)
>> +{
>> +       int rc = 0;
>> +       struct sess_data *sess_data;
>> +
>> +       if (ses == NULL) {
>> +               WARN(1, "%s: ses == NULL!", __func__);
>> +               return -EINVAL;
>> +       }
>> +
>> +       sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
>> +       if (!sess_data)
>> +               return -ENOMEM;
>> +
>> +       rc = select_sec(ses, sess_data);
>> +       if (rc)
>> +               goto out;
>> +
>> +       sess_data->xid = xid;
>> +       sess_data->ses = ses;
>> +       sess_data->buf0_type = CIFS_NO_BUFFER;
>> +       sess_data->nls_cp = (struct nls_table *) nls_cp;
>> +
>> +       while (sess_data->func)
>> +               sess_data->func(sess_data);
>> +
>> +       /* Store result before we free sess_data */
>>         rc = sess_data->result;
>> +
>> +out:
>>         kfree(sess_data);
>>         return rc;
>>  }
>> --
>> 1.9.3
>>
>> --
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-- 
Thanks,

Steve