smb: move client and server files to common directory fs/smb

Move CIFS/SMB3 related client and server files (cifs.ko and ksmbd.ko
and helper modules) to new fs/smb subdirectory:

   fs/cifs --> fs/smb/client
   fs/ksmbd --> fs/smb/server
   fs/smbfs_common --> fs/smb/common

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 1857 insertions, 0 deletions

diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c
new file mode 100644
index 000000000000..335c078c42fb
--- /dev/null
+++ b/fs/smb/client/sess.c
@@ -0,0 +1,1857 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ *
+ *   SMB/CIFS session setup handling routines
+ *
+ *   Copyright (c) International Business Machines  Corp., 2006, 2009
+ *   Author(s): Steve French (sfrench@us.ibm.com)
+ *
+ */
+
+#include "cifspdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_unicode.h"
+#include "cifs_debug.h"
+#include "ntlmssp.h"
+#include "nterr.h"
+#include <linux/utsname.h>
+#include <linux/slab.h>
+#include <linux/version.h>
+#include "cifsfs.h"
+#include "cifs_spnego.h"
+#include "smb2proto.h"
+#include "fs_context.h"
+
+static int
+cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
+		     struct cifs_server_iface *iface);
+
+bool
+is_server_using_iface(struct TCP_Server_Info *server,
+		      struct cifs_server_iface *iface)
+{
+	struct sockaddr_in *i4 = (struct sockaddr_in *)&iface->sockaddr;
+	struct sockaddr_in6 *i6 = (struct sockaddr_in6 *)&iface->sockaddr;
+	struct sockaddr_in *s4 = (struct sockaddr_in *)&server->dstaddr;
+	struct sockaddr_in6 *s6 = (struct sockaddr_in6 *)&server->dstaddr;
+
+	if (server->dstaddr.ss_family != iface->sockaddr.ss_family)
+		return false;
+	if (server->dstaddr.ss_family == AF_INET) {
+		if (s4->sin_addr.s_addr != i4->sin_addr.s_addr)
+			return false;
+	} else if (server->dstaddr.ss_family == AF_INET6) {
+		if (memcmp(&s6->sin6_addr, &i6->sin6_addr,
+			   sizeof(i6->sin6_addr)) != 0)
+			return false;
+	} else {
+		/* unknown family.. */
+		return false;
+	}
+	return true;
+}
+
+bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
+{
+	int i;
+
+	spin_lock(&ses->chan_lock);
+	for (i = 0; i < ses->chan_count; i++) {
+		if (ses->chans[i].iface == iface) {
+			spin_unlock(&ses->chan_lock);
+			return true;
+		}
+	}
+	spin_unlock(&ses->chan_lock);
+	return false;
+}
+
+/* channel helper functions. assumed that chan_lock is held by caller. */
+
+unsigned int
+cifs_ses_get_chan_index(struct cifs_ses *ses,
+			struct TCP_Server_Info *server)
+{
+	unsigned int i;
+
+	for (i = 0; i < ses->chan_count; i++) {
+		if (ses->chans[i].server == server)
+			return i;
+	}
+
+	/* If we didn't find the channel, it is likely a bug */
+	if (server)
+		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
+			 server->conn_id);
+	WARN_ON(1);
+	return 0;
+}
+
+void
+cifs_chan_set_in_reconnect(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	ses->chans[chan_index].in_reconnect = true;
+}
+
+void
+cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	ses->chans[chan_index].in_reconnect = false;
+}
+
+bool
+cifs_chan_in_reconnect(struct cifs_ses *ses,
+			  struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	return CIFS_CHAN_IN_RECONNECT(ses, chan_index);
+}
+
+void
+cifs_chan_set_need_reconnect(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	set_bit(chan_index, &ses->chans_need_reconnect);
+	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
+		 chan_index, ses->chans_need_reconnect);
+}
+
+void
+cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
+			       struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	clear_bit(chan_index, &ses->chans_need_reconnect);
+	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
+		 chan_index, ses->chans_need_reconnect);
+}
+
+bool
+cifs_chan_needs_reconnect(struct cifs_ses *ses,
+			  struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
+}
+
+bool
+cifs_chan_is_iface_active(struct cifs_ses *ses,
+			  struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	return ses->chans[chan_index].iface &&
+		ses->chans[chan_index].iface->is_active;
+}
+
+/* returns number of channels added */
+int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
+{
+	struct TCP_Server_Info *server = ses->server;
+	int old_chan_count, new_chan_count;
+	int left;
+	int rc = 0;
+	int tries = 0;
+	struct cifs_server_iface *iface = NULL, *niface = NULL;
+
+	spin_lock(&ses->chan_lock);
+
+	new_chan_count = old_chan_count = ses->chan_count;
+	left = ses->chan_max - ses->chan_count;
+
+	if (left <= 0) {
+		spin_unlock(&ses->chan_lock);
+		cifs_dbg(FYI,
+			 "ses already at max_channels (%zu), nothing to open\n",
+			 ses->chan_max);
+		return 0;
+	}
+
+	if (server->dialect < SMB30_PROT_ID) {
+		spin_unlock(&ses->chan_lock);
+		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
+		return 0;
+	}
+
+	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
+		ses->chan_max = 1;
+		spin_unlock(&ses->chan_lock);
+		cifs_server_dbg(VFS, "no multichannel support\n");
+		return 0;
+	}
+	spin_unlock(&ses->chan_lock);
+
+	/*
+	 * Keep connecting to same, fastest, iface for all channels as
+	 * long as its RSS. Try next fastest one if not RSS or channel
+	 * creation fails.
+	 */
+	spin_lock(&ses->iface_lock);
+	iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
+				 iface_head);
+	spin_unlock(&ses->iface_lock);
+
+	while (left > 0) {
+
+		tries++;
+		if (tries > 3*ses->chan_max) {
+			cifs_dbg(FYI, "too many channel open attempts (%d channels left to open)\n",
+				 left);
+			break;
+		}
+
+		spin_lock(&ses->iface_lock);
+		if (!ses->iface_count) {
+			spin_unlock(&ses->iface_lock);
+			break;
+		}
+
+		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
+				    iface_head) {
+			/* skip ifaces that are unusable */
+			if (!iface->is_active ||
+			    (is_ses_using_iface(ses, iface) &&
+			     !iface->rss_capable)) {
+				continue;
+			}
+
+			/* take ref before unlock */
+			kref_get(&iface->refcount);
+
+			spin_unlock(&ses->iface_lock);
+			rc = cifs_ses_add_channel(cifs_sb, ses, iface);
+			spin_lock(&ses->iface_lock);
+
+			if (rc) {
+				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
+					 &iface->sockaddr,
+					 rc);
+				kref_put(&iface->refcount, release_iface);
+				continue;
+			}
+
+			cifs_dbg(FYI, "successfully opened new channel on iface:%pIS\n",
+				 &iface->sockaddr);
+			break;
+		}
+		spin_unlock(&ses->iface_lock);
+
+		left--;
+		new_chan_count++;
+	}
+
+	return new_chan_count - old_chan_count;
+}
+
+/*
+ * update the iface for the channel if necessary.
+ * will return 0 when iface is updated, 1 if removed, 2 otherwise
+ * Must be called with chan_lock held.
+ */
+int
+cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
+{
+	unsigned int chan_index;
+	struct cifs_server_iface *iface = NULL;
+	struct cifs_server_iface *old_iface = NULL;
+	int rc = 0;
+
+	spin_lock(&ses->chan_lock);
+	chan_index = cifs_ses_get_chan_index(ses, server);
+	if (!chan_index) {
+		spin_unlock(&ses->chan_lock);
+		return 0;
+	}
+
+	if (ses->chans[chan_index].iface) {
+		old_iface = ses->chans[chan_index].iface;
+		if (old_iface->is_active) {
+			spin_unlock(&ses->chan_lock);
+			return 1;
+		}
+	}
+	spin_unlock(&ses->chan_lock);
+
+	spin_lock(&ses->iface_lock);
+	/* then look for a new one */
+	list_for_each_entry(iface, &ses->iface_list, iface_head) {
+		if (!iface->is_active ||
+		    (is_ses_using_iface(ses, iface) &&
+		     !iface->rss_capable)) {
+			continue;
+		}
+		kref_get(&iface->refcount);
+		break;
+	}
+
+	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
+		rc = 1;
+		iface = NULL;
+		cifs_dbg(FYI, "unable to find a suitable iface\n");
+	}
+
+	/* now drop the ref to the current iface */
+	if (old_iface && iface) {
+		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
+			 &old_iface->sockaddr,
+			 &iface->sockaddr);
+		kref_put(&old_iface->refcount, release_iface);
+	} else if (old_iface) {
+		cifs_dbg(FYI, "releasing ref to iface: %pIS\n",
+			 &old_iface->sockaddr);
+		kref_put(&old_iface->refcount, release_iface);
+	} else {
+		WARN_ON(!iface);
+		cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);
+	}
+	spin_unlock(&ses->iface_lock);
+
+	spin_lock(&ses->chan_lock);
+	chan_index = cifs_ses_get_chan_index(ses, server);
+	ses->chans[chan_index].iface = iface;
+
+	/* No iface is found. if secondary chan, drop connection */
+	if (!iface && CIFS_SERVER_IS_CHAN(server))
+		ses->chans[chan_index].server = NULL;
+
+	spin_unlock(&ses->chan_lock);
+
+	if (!iface && CIFS_SERVER_IS_CHAN(server))
+		cifs_put_tcp_session(server, false);
+
+	return rc;
+}
+
+/*
+ * If server is a channel of ses, return the corresponding enclosing
+ * cifs_chan otherwise return NULL.
+ */
+struct cifs_chan *
+cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server)
+{
+	int i;
+
+	spin_lock(&ses->chan_lock);
+	for (i = 0; i < ses->chan_count; i++) {
+		if (ses->chans[i].server == server) {
+			spin_unlock(&ses->chan_lock);
+			return &ses->chans[i];
+		}
+	}
+	spin_unlock(&ses->chan_lock);
+	return NULL;
+}
+
+static int
+cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
+		     struct cifs_server_iface *iface)
+{
+	struct TCP_Server_Info *chan_server;
+	struct cifs_chan *chan;
+	struct smb3_fs_context ctx = {NULL};
+	static const char unc_fmt[] = "\\%s\\foo";
+	char unc[sizeof(unc_fmt)+SERVER_NAME_LEN_WITH_NULL] = {0};
+	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
+	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
+	int rc;
+	unsigned int xid = get_xid();
+
+	if (iface->sockaddr.ss_family == AF_INET)
+		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
+			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
+			 &ipv4->sin_addr);
+	else
+		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
+			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
+			 &ipv6->sin6_addr);
+
+	/*
+	 * Setup a ctx with mostly the same info as the existing
+	 * session and overwrite it with the requested iface data.
+	 *
+	 * We need to setup at least the fields used for negprot and
+	 * sesssetup.
+	 *
+	 * We only need the ctx here, so we can reuse memory from
+	 * the session and server without caring about memory
+	 * management.
+	 */
+
+	/* Always make new connection for now (TODO?) */
+	ctx.nosharesock = true;
+
+	/* Auth */
+	ctx.domainauto = ses->domainAuto;
+	ctx.domainname = ses->domainName;
+
+	/* no hostname for extra channels */
+	ctx.server_hostname = "";
+
+	ctx.username = ses->user_name;
+	ctx.password = ses->password;
+	ctx.sectype = ses->sectype;
+	ctx.sign = ses->sign;
+
+	/* UNC and paths */
+	/* XXX: Use ses->server->hostname? */
+	sprintf(unc, unc_fmt, ses->ip_addr);
+	ctx.UNC = unc;
+	ctx.prepath = "";
+
+	/* Reuse same version as master connection */
+	ctx.vals = ses->server->vals;
+	ctx.ops = ses->server->ops;
+
+	ctx.noblocksnd = ses->server->noblocksnd;
+	ctx.noautotune = ses->server->noautotune;
+	ctx.sockopt_tcp_nodelay = ses->server->tcp_nodelay;
+	ctx.echo_interval = ses->server->echo_interval / HZ;
+	ctx.max_credits = ses->server->max_credits;
+
+	/*
+	 * This will be used for encoding/decoding user/domain/pw
+	 * during sess setup auth.
+	 */
+	ctx.local_nls = cifs_sb->local_nls;
+
+	/* Use RDMA if possible */
+	ctx.rdma = iface->rdma_capable;
+	memcpy(&ctx.dstaddr, &iface->sockaddr, sizeof(struct sockaddr_storage));
+
+	/* reuse master con client guid */
+	memcpy(&ctx.client_guid, ses->server->client_guid,
+	       SMB2_CLIENT_GUID_SIZE);
+	ctx.use_client_guid = true;
+
+	chan_server = cifs_get_tcp_session(&ctx, ses->server);
+
+	spin_lock(&ses->chan_lock);
+	chan = &ses->chans[ses->chan_count];
+	chan->server = chan_server;
+	if (IS_ERR(chan->server)) {
+		rc = PTR_ERR(chan->server);
+		chan->server = NULL;
+		spin_unlock(&ses->chan_lock);
+		goto out;
+	}
+	chan->iface = iface;
+	ses->chan_count++;
+	atomic_set(&ses->chan_seq, 0);
+
+	/* Mark this channel as needing connect/setup */
+	cifs_chan_set_need_reconnect(ses, chan->server);
+
+	spin_unlock(&ses->chan_lock);
+
+	mutex_lock(&ses->session_mutex);
+	/*
+	 * We need to allocate the server crypto now as we will need
+	 * to sign packets before we generate the channel signing key
+	 * (we sign with the session key)
+	 */
+	rc = smb311_crypto_shash_allocate(chan->server);
+	if (rc) {
+		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
+		mutex_unlock(&ses->session_mutex);
+		goto out;
+	}
+
+	rc = cifs_negotiate_protocol(xid, ses, chan->server);
+	if (!rc)
+		rc = cifs_setup_session(xid, ses, chan->server, cifs_sb->local_nls);
+
+	mutex_unlock(&ses->session_mutex);
+
+out:
+	if (rc && chan->server) {
+		/*
+		 * we should avoid race with these delayed works before we
+		 * remove this channel
+		 */
+		cancel_delayed_work_sync(&chan->server->echo);
+		cancel_delayed_work_sync(&chan->server->reconnect);
+
+		spin_lock(&ses->chan_lock);
+		/* we rely on all bits beyond chan_count to be clear */
+		cifs_chan_clear_need_reconnect(ses, chan->server);
+		ses->chan_count--;
+		/*
+		 * chan_count should never reach 0 as at least the primary
+		 * channel is always allocated
+		 */
+		WARN_ON(ses->chan_count < 1);
+		spin_unlock(&ses->chan_lock);
+
+		cifs_put_tcp_session(chan->server, 0);
+	}
+
+	free_xid(xid);
+	return rc;
+}
+
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server,
+			     SESSION_SETUP_ANDX *pSMB)
+{
+	__u32 capabilities = 0;
+
+	/* init fields common to all four types of SessSetup */
+	/* Note that offsets for first seven fields in req struct are same  */
+	/*	in CIFS Specs so does not matter which of 3 forms of struct */
+	/*	that we use in next few lines                               */
+	/* Note that header is initialized to zero in header_assemble */
+	pSMB->req.AndXCommand = 0xFF;
+	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
+					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
+					USHRT_MAX));
+	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
+	pSMB->req.VcNumber = cpu_to_le16(1);
+
+	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
+
+	/* BB verify whether signing required on neg or just on auth frame
+	   (and NTLM case) */
+
+	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
+			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
+
+	if (server->sign)
+		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
+	if (ses->capabilities & CAP_UNICODE) {
+		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
+		capabilities |= CAP_UNICODE;
+	}
+	if (ses->capabilities & CAP_STATUS32) {
+		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
+		capabilities |= CAP_STATUS32;
+	}
+	if (ses->capabilities & CAP_DFS) {
+		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
+		capabilities |= CAP_DFS;
+	}
+	if (ses->capabilities & CAP_UNIX)
+		capabilities |= CAP_UNIX;
+
+	return capabilities;
+}
+
+static void
+unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
+{
+	char *bcc_ptr = *pbcc_area;
+	int bytes_ret = 0;
+
+	/* Copy OS version */
+	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
+				    nls_cp);
+	bcc_ptr += 2 * bytes_ret;
+	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
+				    32, nls_cp);
+	bcc_ptr += 2 * bytes_ret;
+	bcc_ptr += 2; /* trailing null */
+
+	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
+				    32, nls_cp);
+	bcc_ptr += 2 * bytes_ret;
+	bcc_ptr += 2; /* trailing null */
+
+	*pbcc_area = bcc_ptr;
+}
+
+static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
+				   const struct nls_table *nls_cp)
+{
+	char *bcc_ptr = *pbcc_area;
+	int bytes_ret = 0;
+
+	/* copy domain */
+	if (ses->domainName == NULL) {
+		/* Sending null domain better than using a bogus domain name (as
+		we did briefly in 2.6.18) since server will use its default */
+		*bcc_ptr = 0;
+		*(bcc_ptr+1) = 0;
+		bytes_ret = 0;
+	} else
+		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
+					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
+	bcc_ptr += 2 * bytes_ret;
+	bcc_ptr += 2;  /* account for null terminator */
+
+	*pbcc_area = bcc_ptr;
+}
+
+static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
+				   const struct nls_table *nls_cp)
+{
+	char *bcc_ptr = *pbcc_area;
+	int bytes_ret = 0;
+
+	/* BB FIXME add check that strings total less
+	than 335 or will need to send them as arrays */
+
+	/* copy user */
+	if (ses->user_name == NULL) {
+		/* null user mount */
+		*bcc_ptr = 0;
+		*(bcc_ptr+1) = 0;
+	} else {
+		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
+					    CIFS_MAX_USERNAME_LEN, nls_cp);
+	}
+	bcc_ptr += 2 * bytes_ret;
+	bcc_ptr += 2; /* account for null termination */
+
+	unicode_domain_string(&bcc_ptr, ses, nls_cp);
+	unicode_oslm_strings(&bcc_ptr, nls_cp);
+
+	*pbcc_area = bcc_ptr;
+}
+
+static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
+				 const struct nls_table *nls_cp)
+{
+	char *bcc_ptr = *pbcc_area;
+	int len;
+
+	/* copy user */
+	/* BB what about null user mounts - check that we do this BB */
+	/* copy user */
+	if (ses->user_name != NULL) {
+		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
+		if (WARN_ON_ONCE(len < 0))
+			len = CIFS_MAX_USERNAME_LEN - 1;
+		bcc_ptr += len;
+	}
+	/* else null user mount */
+	*bcc_ptr = 0;
+	bcc_ptr++; /* account for null termination */
+
+	/* copy domain */
+	if (ses->domainName != NULL) {
+		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
+		if (WARN_ON_ONCE(len < 0))
+			len = CIFS_MAX_DOMAINNAME_LEN - 1;
+		bcc_ptr += len;
+	} /* else we will send a null domain name
+	     so the server will default to its own domain */
+	*bcc_ptr = 0;
+	bcc_ptr++;
+
+	/* BB check for overflow here */
+
+	strcpy(bcc_ptr, "Linux version ");
+	bcc_ptr += strlen("Linux version ");
+	strcpy(bcc_ptr, init_utsname()->release);
+	bcc_ptr += strlen(init_utsname()->release) + 1;
+
+	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
+	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
+
+	*pbcc_area = bcc_ptr;
+}
+
+static void
+decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
+		      const struct nls_table *nls_cp)
+{
+	int len;
+	char *data = *pbcc_area;
+
+	cifs_dbg(FYI, "bleft %d\n", bleft);
+
+	kfree(ses->serverOS);
+	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
+	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
+	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
+	data += len;
+	bleft -= len;
+	if (bleft <= 0)
+		return;
+
+	kfree(ses->serverNOS);
+	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
+	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
+	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
+	data += len;
+	bleft -= len;
+	if (bleft <= 0)
+		return;
+
+	kfree(ses->serverDomain);
+	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
+	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
+
+	return;
+}
+
+static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
+				struct cifs_ses *ses,
+				const struct nls_table *nls_cp)
+{
+	int len;
+	char *bcc_ptr = *pbcc_area;
+
+	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
+
+	len = strnlen(bcc_ptr, bleft);
+	if (len >= bleft)
+		return;
+
+	kfree(ses->serverOS);
+
+	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
+	if (ses->serverOS) {
+		memcpy(ses->serverOS, bcc_ptr, len);
+		ses->serverOS[len] = 0;
+		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
+			cifs_dbg(FYI, "OS/2 server\n");
+	}
+
+	bcc_ptr += len + 1;
+	bleft -= len + 1;
+
+	len = strnlen(bcc_ptr, bleft);
+	if (len >= bleft)
+		return;
+
+	kfree(ses->serverNOS);
+
+	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
+	if (ses->serverNOS) {
+		memcpy(ses->serverNOS, bcc_ptr, len);
+		ses->serverNOS[len] = 0;
+	}
+
+	bcc_ptr += len + 1;
+	bleft -= len + 1;
+
+	len = strnlen(bcc_ptr, bleft);
+	if (len > bleft)
+		return;
+
+	/* No domain field in LANMAN case. Domain is
+	   returned by old servers in the SMB negprot response */
+	/* BB For newer servers which do not support Unicode,
+	   but thus do return domain here we could add parsing
+	   for it later, but it is not very important */
+	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
+}
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
+
+int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
+				    struct cifs_ses *ses)
+{
+	unsigned int tioffset; /* challenge message target info area */
+	unsigned int tilen; /* challenge message target info area length  */
+	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
+	__u32 server_flags;
+
+	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
+		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
+		return -EINVAL;
+	}
+
+	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
+		cifs_dbg(VFS, "blob signature incorrect %s\n",
+			 pblob->Signature);
+		return -EINVAL;
+	}
+	if (pblob->MessageType != NtLmChallenge) {
+		cifs_dbg(VFS, "Incorrect message type %d\n",
+			 pblob->MessageType);
+		return -EINVAL;
+	}
+
+	server_flags = le32_to_cpu(pblob->NegotiateFlags);
+	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
+		 ses->ntlmssp->client_flags, server_flags);
+
+	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
+	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
+		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
+			 __func__);
+		return -EINVAL;
+	}
+	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
+		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
+		return -EINVAL;
+	}
+	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
+		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
+			 __func__);
+		return -EOPNOTSUPP;
+	}
+	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
+	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
+		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
+			     __func__);
+
+	ses->ntlmssp->server_flags = server_flags;
+
+	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
+	/* In particular we can examine sign flags */
+	/* BB spec says that if AvId field of MsvAvTimestamp is populated then
+		we must set the MIC field of the AUTHENTICATE_MESSAGE */
+
+	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
+	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
+	if (tioffset > blob_len || tioffset + tilen > blob_len) {
+		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
+			 tioffset, tilen);
+		return -EINVAL;
+	}
+	if (tilen) {
+		kfree_sensitive(ses->auth_key.response);
+		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
+						 GFP_KERNEL);
+		if (!ses->auth_key.response) {
+			cifs_dbg(VFS, "Challenge target info alloc failure\n");
+			return -ENOMEM;
+		}
+		ses->auth_key.len = tilen;
+	}
+
+	return 0;
+}
+
+static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
+{
+	int sz = base_size + ses->auth_key.len
+		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
+
+	if (ses->domainName)
+		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
+	else
+		sz += sizeof(__le16);
+
+	if (ses->user_name)
+		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
+	else
+		sz += sizeof(__le16);
+
+	if (ses->workstation_name[0])
+		sz += sizeof(__le16) * strnlen(ses->workstation_name,
+					       ntlmssp_workstation_name_size(ses));
+	else
+		sz += sizeof(__le16);
+
+	return sz;
+}
+
+static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
+						 char *str_value,
+						 int str_length,
+						 unsigned char *pstart,
+						 unsigned char **pcur,
+						 const struct nls_table *nls_cp)
+{
+	unsigned char *tmp = pstart;
+	int len;
+
+	if (!pbuf)
+		return;
+
+	if (!pcur)
+		pcur = &tmp;
+
+	if (!str_value) {
+		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
+		pbuf->Length = 0;
+		pbuf->MaximumLength = 0;
+		*pcur += sizeof(__le16);
+	} else {
+		len = cifs_strtoUTF16((__le16 *)*pcur,
+				      str_value,
+				      str_length,
+				      nls_cp);
+		len *= sizeof(__le16);
+		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
+		pbuf->Length = cpu_to_le16(len);
+		pbuf->MaximumLength = cpu_to_le16(len);
+		*pcur += len;
+	}
+}
+
+/* BB Move to ntlmssp.c eventually */
+
+int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
+				 u16 *buflen,
+				 struct cifs_ses *ses,
+				 struct TCP_Server_Info *server,
+				 const struct nls_table *nls_cp)
+{
+	int rc = 0;
+	NEGOTIATE_MESSAGE *sec_blob;
+	__u32 flags;
+	unsigned char *tmp;
+	int len;
+
+	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
+	*pbuffer = kmalloc(len, GFP_KERNEL);
+	if (!*pbuffer) {
+		rc = -ENOMEM;
+		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
+		*buflen = 0;
+		goto setup_ntlm_neg_ret;
+	}
+	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
+
+	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
+	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
+	sec_blob->MessageType = NtLmNegotiate;
+
+	/* BB is NTLMV2 session security format easier to use here? */
+	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
+		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
+		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
+		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
+		NTLMSSP_NEGOTIATE_SIGN;
+	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
+		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
+
+	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
+	ses->ntlmssp->client_flags = flags;
+	sec_blob->NegotiateFlags = cpu_to_le32(flags);
+
+	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
+	cifs_security_buffer_from_str(&sec_blob->DomainName,
+				      NULL,
+				      CIFS_MAX_DOMAINNAME_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
+				      NULL,
+				      CIFS_MAX_WORKSTATION_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	*buflen = tmp - *pbuffer;
+setup_ntlm_neg_ret:
+	return rc;
+}
+
+/*
+ * Build ntlmssp blob with additional fields, such as version,
+ * supported by modern servers. For safety limit to SMB3 or later
+ * See notes in MS-NLMP Section 2.2.2.1 e.g.
+ */
+int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
+				 u16 *buflen,
+				 struct cifs_ses *ses,
+				 struct TCP_Server_Info *server,
+				 const struct nls_table *nls_cp)
+{
+	int rc = 0;
+	struct negotiate_message *sec_blob;
+	__u32 flags;
+	unsigned char *tmp;
+	int len;
+
+	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
+	*pbuffer = kmalloc(len, GFP_KERNEL);
+	if (!*pbuffer) {
+		rc = -ENOMEM;
+		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
+		*buflen = 0;
+		goto setup_ntlm_smb3_neg_ret;
+	}
+	sec_blob = (struct negotiate_message *)*pbuffer;
+
+	memset(*pbuffer, 0, sizeof(struct negotiate_message));
+	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
+	sec_blob->MessageType = NtLmNegotiate;
+
+	/* BB is NTLMV2 session security format easier to use here? */
+	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
+		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
+		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
+		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
+		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
+	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
+		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
+
+	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
+	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
+	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
+	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
+
+	tmp = *pbuffer + sizeof(struct negotiate_message);
+	ses->ntlmssp->client_flags = flags;
+	sec_blob->NegotiateFlags = cpu_to_le32(flags);
+
+	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
+	cifs_security_buffer_from_str(&sec_blob->DomainName,
+				      NULL,
+				      CIFS_MAX_DOMAINNAME_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
+				      NULL,
+				      CIFS_MAX_WORKSTATION_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	*buflen = tmp - *pbuffer;
+setup_ntlm_smb3_neg_ret:
+	return rc;
+}
+
+
+int build_ntlmssp_auth_blob(unsigned char **pbuffer,
+					u16 *buflen,
+				   struct cifs_ses *ses,
+				   struct TCP_Server_Info *server,
+				   const struct nls_table *nls_cp)
+{
+	int rc;
+	AUTHENTICATE_MESSAGE *sec_blob;
+	__u32 flags;
+	unsigned char *tmp;
+	int len;
+
+	rc = setup_ntlmv2_rsp(ses, nls_cp);
+	if (rc) {
+		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
+		*buflen = 0;
+		goto setup_ntlmv2_ret;
+	}
+
+	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
+	*pbuffer = kmalloc(len, GFP_KERNEL);
+	if (!*pbuffer) {
+		rc = -ENOMEM;
+		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
+		*buflen = 0;
+		goto setup_ntlmv2_ret;
+	}
+	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
+
+	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
+	sec_blob->MessageType = NtLmAuthenticate;
+
+	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
+		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
+
+	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
+	sec_blob->NegotiateFlags = cpu_to_le32(flags);
+
+	sec_blob->LmChallengeResponse.BufferOffset =
+				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
+	sec_blob->LmChallengeResponse.Length = 0;
+	sec_blob->LmChallengeResponse.MaximumLength = 0;
+
+	sec_blob->NtChallengeResponse.BufferOffset =
+				cpu_to_le32(tmp - *pbuffer);
+	if (ses->user_name != NULL) {
+		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
+				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
+		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
+
+		sec_blob->NtChallengeResponse.Length =
+				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
+		sec_blob->NtChallengeResponse.MaximumLength =
+				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
+	} else {
+		/*
+		 * don't send an NT Response for anonymous access
+		 */
+		sec_blob->NtChallengeResponse.Length = 0;
+		sec_blob->NtChallengeResponse.MaximumLength = 0;
+	}
+
+	cifs_security_buffer_from_str(&sec_blob->DomainName,
+				      ses->domainName,
+				      CIFS_MAX_DOMAINNAME_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	cifs_security_buffer_from_str(&sec_blob->UserName,
+				      ses->user_name,
+				      CIFS_MAX_USERNAME_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
+				      ses->workstation_name,
+				      ntlmssp_workstation_name_size(ses),
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
+	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
+	    !calc_seckey(ses)) {
+		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
+		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
+		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
+		sec_blob->SessionKey.MaximumLength =
+				cpu_to_le16(CIFS_CPHTXT_SIZE);
+		tmp += CIFS_CPHTXT_SIZE;
+	} else {
+		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
+		sec_blob->SessionKey.Length = 0;
+		sec_blob->SessionKey.MaximumLength = 0;
+	}
+
+	*buflen = tmp - *pbuffer;
+setup_ntlmv2_ret:
+	return rc;
+}
+
+enum securityEnum
+cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
+{
+	switch (server->negflavor) {
+	case CIFS_NEGFLAVOR_EXTENDED:
+		switch (requested) {
+		case Kerberos:
+		case RawNTLMSSP:
+			return requested;
+		case Unspecified:
+			if (server->sec_ntlmssp &&
+			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
+				return RawNTLMSSP;
+			if ((server->sec_kerberos || server->sec_mskerberos) &&
+			    (global_secflags & CIFSSEC_MAY_KRB5))
+				return Kerberos;
+			fallthrough;
+		default:
+			return Unspecified;
+		}
+	case CIFS_NEGFLAVOR_UNENCAP:
+		switch (requested) {
+		case NTLMv2:
+			return requested;
+		case Unspecified:
+			if (global_secflags & CIFSSEC_MAY_NTLMV2)
+				return NTLMv2;
+			break;
+		default:
+			break;
+		}
+		fallthrough;
+	default:
+		return Unspecified;
+	}
+}
+
+struct sess_data {
+	unsigned int xid;
+	struct cifs_ses *ses;
+	struct TCP_Server_Info *server;
+	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];
+};
+
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+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:
+	cifs_small_buf_release(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)
+{
+	struct kvec *iov = sess_data->iov;
+
+	/*
+	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
+	 * Note that iov[1] is already freed by caller.
+	 */
+	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
+		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
+
+	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
+	sess_data->buf0_type = CIFS_NO_BUFFER;
+	kfree_sensitive(iov[2].iov_base);
+}
+
+static int
+sess_establish_session(struct sess_data *sess_data)
+{
+	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
+
+	cifs_server_lock(server);
+	if (!server->session_estab) {
+		if (server->sign) {
+			server->session_key.response =
+				kmemdup(ses->auth_key.response,
+				ses->auth_key.len, GFP_KERNEL);
+			if (!server->session_key.response) {
+				cifs_server_unlock(server);
+				return -ENOMEM;
+			}
+			server->session_key.len =
+						ses->auth_key.len;
+		}
+		server->sequence_number = 0x2;
+		server->session_estab = true;
+	}
+	cifs_server_unlock(server);
+
+	cifs_dbg(FYI, "CIFS session established successfully\n");
+	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;
+	struct kvec rsp_iov = { NULL, 0 };
+
+	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
+	be32_add_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, &rsp_iov);
+	cifs_small_buf_release(sess_data->iov[0].iov_base);
+	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
+
+	return rc;
+}
+
+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;
+	struct TCP_Server_Info *server = sess_data->server;
+	__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, server, 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;
+
+	if (ses->user_name != NULL) {
+		/* 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);
+	} else {
+		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
+	}
+
+	if (ses->capabilities & CAP_UNICODE) {
+		if (!IS_ALIGNED(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 (!IS_ALIGNED((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_sensitive(ses->auth_key.response);
+	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;
+	struct TCP_Server_Info *server = sess_data->server;
+	__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, server, pSMB);
+
+	spnego_key = cifs_get_spnego_key(ses, server);
+	if (IS_ERR(spnego_key)) {
+		rc = PTR_ERR(spnego_key);
+		spnego_key = NULL;
+		goto out;
+	}
+
+	msg = spnego_key->payload.data[0];
+	/*
+	 * 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)\n",
+			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
+		rc = -EKEYREJECTED;
+		goto out_put_spnego_key;
+	}
+
+	kfree_sensitive(ses->auth_key.response);
+	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\n",
+			 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 (!IS_ALIGNED(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 (!IS_ALIGNED((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_sensitive(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+}
+
+#endif /* ! CONFIG_CIFS_UPCALL */
+
+/*
+ * The required kvec buffers have to be allocated before calling this
+ * function.
+ */
+static int
+_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
+{
+	SESSION_SETUP_ANDX *pSMB;
+	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
+	__u32 capabilities;
+	char *bcc_ptr;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+
+	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
+	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
+		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
+		return -ENOSYS;
+	}
+
+	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
+	capabilities |= CAP_EXTENDED_SECURITY;
+	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
+
+	bcc_ptr = sess_data->iov[2].iov_base;
+	/* unicode strings must be word aligned */
+	if (!IS_ALIGNED(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);
+
+	sess_data->iov[2].iov_len = (long) bcc_ptr -
+					(long) sess_data->iov[2].iov_base;
+
+	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;
+	struct TCP_Server_Info *server = sess_data->server;
+	__u16 bytes_remaining;
+	char *bcc_ptr;
+	unsigned char *ntlmsspblob = NULL;
+	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;
+
+	/* wct = 12 */
+	rc = sess_alloc_buffer(sess_data, 12);
+	if (rc)
+		goto out;
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+
+	/* Build security blob before we assemble the request */
+	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
+				     &blob_len, ses, server,
+				     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);
+
+	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
+	if (rc)
+		goto out_free_ntlmsspblob;
+
+	rc = sess_sendreceive(sess_data);
+
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
+
+	/* 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;
+
+	if (rc)
+		goto out_free_ntlmsspblob;
+
+	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_free_ntlmsspblob;
+	}
+
+	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_free_ntlmsspblob;
+	}
+
+	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
+
+out_free_ntlmsspblob:
+	kfree_sensitive(ntlmsspblob);
+out:
+	sess_free_buffer(sess_data);
+
+	if (!rc) {
+		sess_data->func = sess_auth_rawntlmssp_authenticate;
+		return;
+	}
+
+	/* Else error. Cleanup */
+	kfree_sensitive(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+	kfree_sensitive(ses->ntlmssp);
+	ses->ntlmssp = NULL;
+
+	sess_data->func = NULL;
+	sess_data->result = rc;
+}
+
+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;
+	struct TCP_Server_Info *server = sess_data->server;
+	__u16 bytes_remaining;
+	char *bcc_ptr;
+	unsigned char *ntlmsspblob = NULL;
+	u16 blob_len;
+
+	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
+
+	/* wct = 12 */
+	rc = sess_alloc_buffer(sess_data, 12);
+	if (rc)
+		goto out;
+
+	/* Build security blob before we assemble the request */
+	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
+	smb_buf = (struct smb_hdr *)pSMB;
+	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
+					&blob_len, ses, server,
+					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 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 out_free_ntlmsspblob;
+	}
+
+	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
+		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
+
+	if (ses->Suid != smb_buf->Uid) {
+		ses->Suid = smb_buf->Uid;
+		cifs_dbg(FYI, "UID changed! new 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_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 */
+	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
+		/* unicode string area must be word-aligned */
+		if (!IS_ALIGNED((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);
+	}
+
+out_free_ntlmsspblob:
+	kfree_sensitive(ntlmsspblob);
+out:
+	sess_free_buffer(sess_data);
+
+	if (!rc)
+		rc = sess_establish_session(sess_data);
+
+	/* Cleanup */
+	kfree_sensitive(ses->auth_key.response);
+	ses->auth_key.response = NULL;
+	kfree_sensitive(ses->ntlmssp);
+	ses->ntlmssp = NULL;
+
+	sess_data->func = NULL;
+	sess_data->result = rc;
+}
+
+static int select_sec(struct sess_data *sess_data)
+{
+	int type;
+	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
+
+	type = cifs_select_sectype(server, ses->sectype);
+	cifs_dbg(FYI, "sess setup type %d\n", type);
+	if (type == Unspecified) {
+		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
+		return -EINVAL;
+	}
+
+	switch (type) {
+	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;
+#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,
+		   struct TCP_Server_Info *server,
+		   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;
+
+	sess_data->xid = xid;
+	sess_data->ses = ses;
+	sess_data->server = server;
+	sess_data->buf0_type = CIFS_NO_BUFFER;
+	sess_data->nls_cp = (struct nls_table *) nls_cp;
+
+	rc = select_sec(sess_data);
+	if (rc)
+		goto out;
+
+	while (sess_data->func)
+		sess_data->func(sess_data);
+
+	/* Store result before we free sess_data */
+	rc = sess_data->result;
+
+out:
+	kfree_sensitive(sess_data);
+	return rc;
+}
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */