/*
   *   fs/cifs/cifsencrypt.c
   *

   *   Copyright (C) International Business Machines  Corp., 2005,2006

   *   Author(s): Steve French (sfrench@us.ibm.com)
   *
   *   This library is free software; you can redistribute it and/or modify
   *   it under the terms of the GNU Lesser General Public License as published
   *   by the Free Software Foundation; either version 2.1 of the License, or
   *   (at your option) any later version.
   *
   *   This library is distributed in the hope that it will be useful,
   *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
   *   the GNU Lesser General Public License for more details.
   *
   *   You should have received a copy of the GNU Lesser General Public License
   *   along with this library; if not, write to the Free Software
   *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   */
  
  #include <linux/fs.h>

  #include <linux/slab.h>

  #include "cifspdu.h"

  #include "cifsglob.h"

  #include "cifs_debug.h"

  #include "cifs_unicode.h"
  #include "cifsproto.h"

  #include "ntlmssp.h"

  #include <linux/ctype.h>

  #include <linux/random.h>

  /*
   * Calculate and return the CIFS signature based on the mac key and SMB PDU.
   * The 16 byte signature must be allocated by the caller. Note we only use the
   * 1st eight bytes and that the smb header signature field on input contains
   * the sequence number before this function is called. Also, this function
   * should be called with the server->srv_mutex held.
   */

  static int cifs_calc_signature(const struct kvec *iov, int n_vec,
  			struct TCP_Server_Info *server, char *signature)

  {

  	int i;

  	int rc;

  	if (iov == NULL || signature == NULL || server == NULL)

  		return -EINVAL;

  	if (!server->secmech.sdescmd5) {
  		cERROR(1, "%s: Can't generate signature
  ", __func__);
  		return -1;
  	}
  
  	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
  	if (rc) {

  		cERROR(1, "%s: Could not init md5
  ", __func__);

  		return rc;
  	}

  	rc = crypto_shash_update(&server->secmech.sdescmd5->shash,

  		server->session_key.response, server->session_key.len);

  	if (rc) {
  		cERROR(1, "%s: Could not update with response
  ", __func__);
  		return rc;
  	}

  	for (i = 0; i < n_vec; i++) {

  		if (iov[i].iov_len == 0)
  			continue;

  		if (iov[i].iov_base == NULL) {

  			cERROR(1, "null iovec entry");

  			return -EIO;

  		}

  		/* The first entry includes a length field (which does not get

  		   signed that occupies the first 4 bytes before the header */

  		if (i == 0) {

  			if (iov[0].iov_len <= 8) /* cmd field at offset 9 */

  				break; /* nothing to sign or corrupt header */

  			rc =

  			crypto_shash_update(&server->secmech.sdescmd5->shash,
  				iov[i].iov_base + 4, iov[i].iov_len - 4);

  		} else {
  			rc =

  			crypto_shash_update(&server->secmech.sdescmd5->shash,
  				iov[i].iov_base, iov[i].iov_len);

  		}
  		if (rc) {
  			cERROR(1, "%s: Could not update with payload
  ",
  							__func__);
  			return rc;
  		}

  	}

  	rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);

  	if (rc)
  		cERROR(1, "%s: Could not generate md5 hash
  ", __func__);

  	return rc;

  }

  /* must be called with server->srv_mutex held */

  int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,

  		   __u32 *pexpected_response_sequence_number)

  {
  	int rc = 0;
  	char smb_signature[20];

  	struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;

  	if ((cifs_pdu == NULL) || (server == NULL))

  		return -EINVAL;

  	if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
  	    server->tcpStatus == CifsNeedNegotiate)

  		return rc;

  	if (!server->session_estab) {

  		memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);

  		return rc;
  	}

  	cifs_pdu->Signature.Sequence.SequenceNumber =

  				cpu_to_le32(server->sequence_number);

  	cifs_pdu->Signature.Sequence.Reserved = 0;

  	*pexpected_response_sequence_number = server->sequence_number++;
  	server->sequence_number++;

  	rc = cifs_calc_signature(iov, n_vec, server, smb_signature);

  	if (rc)
  		memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
  	else
  		memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);

  	return rc;

  }

  /* must be called with server->srv_mutex held */
  int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
  		  __u32 *pexpected_response_sequence_number)
  {
  	struct kvec iov;
  
  	iov.iov_base = cifs_pdu;
  	iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
  
  	return cifs_sign_smb2(&iov, 1, server,
  			      pexpected_response_sequence_number);
  }
  
  int cifs_verify_signature(struct kvec *iov, unsigned int nr_iov,

  			  struct TCP_Server_Info *server,

  			  __u32 expected_sequence_number)

  {

  	unsigned int rc;

  	char server_response_sig[8];
  	char what_we_think_sig_should_be[20];

  	struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;

  	if (cifs_pdu == NULL || server == NULL)

  		return -EINVAL;

  	if (!server->session_estab)

  		return 0;
  
  	if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {

  		struct smb_com_lock_req *pSMB =

  			(struct smb_com_lock_req *)cifs_pdu;
  	    if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)

  			return 0;
  	}

  	/* BB what if signatures are supposed to be on for session but
  	   server does not send one? BB */

  	/* Do not need to verify session setups with signature "BSRSPYL "  */

  	if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)

  		cFYI(1, "dummy signature received for smb command 0x%x",
  			cifs_pdu->Command);

  
  	/* save off the origiginal signature so we can modify the smb and check
  		its signature against what the server sent */

  	memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);

  	cifs_pdu->Signature.Sequence.SequenceNumber =
  					cpu_to_le32(expected_sequence_number);

  	cifs_pdu->Signature.Sequence.Reserved = 0;

  	mutex_lock(&server->srv_mutex);

  	rc = cifs_calc_signature(iov, nr_iov, server,
  				 what_we_think_sig_should_be);

  	mutex_unlock(&server->srv_mutex);

  	if (rc)

  		return rc;

  /*	cifs_dump_mem("what we think it should be: ",
  		      what_we_think_sig_should_be, 16); */

  	if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))

  		return -EACCES;
  	else
  		return 0;
  
  }

  /* first calculate 24 bytes ntlm response and then 16 byte session key */

  int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)

  {

  	int rc = 0;

  	unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
  	char temp_key[CIFS_SESS_KEY_SIZE];
  
  	if (!ses)

  		return -EINVAL;

  	ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
  	if (!ses->auth_key.response) {
  		cERROR(1, "NTLM can't allocate (%u bytes) memory", temp_len);
  		return -ENOMEM;
  	}
  	ses->auth_key.len = temp_len;

  	rc = SMBNTencrypt(ses->password, ses->server->cryptkey,

  			ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);

  	if (rc) {
  		cFYI(1, "%s Can't generate NTLM response, error: %d",
  			__func__, rc);
  		return rc;
  	}

  	rc = E_md4hash(ses->password, temp_key, nls_cp);

  	if (rc) {
  		cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
  		return rc;
  	}

  	rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
  	if (rc)
  		cFYI(1, "%s Can't generate NTLM session key, error: %d",
  			__func__, rc);

  	return rc;

  }

  #ifdef CONFIG_CIFS_WEAK_PW_HASH

  int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,

  			char *lnm_session_key)

  {
  	int i;

  	int rc;

  	char password_with_pad[CIFS_ENCPWD_SIZE];
  
  	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);

  	if (password)
  		strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);

  	if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {

  		memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE);
  		memcpy(lnm_session_key, password_with_pad,
  			CIFS_ENCPWD_SIZE);

  		return 0;

  	}

  	/* calculate old style session key */
  	/* calling toupper is less broken than repeatedly
  	calling nls_toupper would be since that will never
  	work for UTF8, but neither handles multibyte code pages
  	but the only alternative would be converting to UCS-16 (Unicode)
  	(using a routine something like UniStrupr) then
  	uppercasing and then converting back from Unicode - which
  	would only worth doing it if we knew it were utf8. Basically
  	utf8 and other multibyte codepages each need their own strupper
  	function since a byte at a time will ont work. */

  	for (i = 0; i < CIFS_ENCPWD_SIZE; i++)

  		password_with_pad[i] = toupper(password_with_pad[i]);

  	rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);

  	return rc;

  }
  #endif /* CIFS_WEAK_PW_HASH */

  /* Build a proper attribute value/target info pairs blob.
   * Fill in netbios and dns domain name and workstation name
   * and client time (total five av pairs and + one end of fields indicator.
   * Allocate domain name which gets freed when session struct is deallocated.

   */
  static int

  build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)

  {

  	unsigned int dlen;

  	unsigned int size = 2 * sizeof(struct ntlmssp2_name);

  	char *defdmname = "WORKGROUP";
  	unsigned char *blobptr;

  	struct ntlmssp2_name *attrptr;

  	if (!ses->domainName) {
  		ses->domainName = kstrdup(defdmname, GFP_KERNEL);
  		if (!ses->domainName)
  			return -ENOMEM;
  	}
  
  	dlen = strlen(ses->domainName);

  	/*
  	 * The length of this blob is two times the size of a
  	 * structure (av pair) which holds name/size
  	 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
  	 * unicode length of a netbios domain name

  	 */

  	ses->auth_key.len = size + 2 * dlen;

  	ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
  	if (!ses->auth_key.response) {
  		ses->auth_key.len = 0;

  		cERROR(1, "Challenge target info allocation failure");
  		return -ENOMEM;
  	}

  	blobptr = ses->auth_key.response;

  	attrptr = (struct ntlmssp2_name *) blobptr;

  	/*
  	 * As defined in MS-NTLM 3.3.2, just this av pair field
  	 * is sufficient as part of the temp
  	 */

  	attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
  	attrptr->length = cpu_to_le16(2 * dlen);
  	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
  	cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);

  	return 0;
  }
  
  /* Server has provided av pairs/target info in the type 2 challenge
   * packet and we have plucked it and stored within smb session.
   * We parse that blob here to find netbios domain name to be used
   * as part of ntlmv2 authentication (in Target String), if not already
   * specified on the command line.
   * If this function returns without any error but without fetching
   * domain name, authentication may fail against some server but
   * may not fail against other (those who are not very particular
   * about target string i.e. for some, just user name might suffice.
   */
  static int

  find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)

  {
  	unsigned int attrsize;
  	unsigned int type;
  	unsigned int onesize = sizeof(struct ntlmssp2_name);
  	unsigned char *blobptr;
  	unsigned char *blobend;
  	struct ntlmssp2_name *attrptr;

  	if (!ses->auth_key.len || !ses->auth_key.response)

  		return 0;

  	blobptr = ses->auth_key.response;
  	blobend = blobptr + ses->auth_key.len;

  
  	while (blobptr + onesize < blobend) {
  		attrptr = (struct ntlmssp2_name *) blobptr;
  		type = le16_to_cpu(attrptr->type);
  		if (type == NTLMSSP_AV_EOL)
  			break;
  		blobptr += 2; /* advance attr type */
  		attrsize = le16_to_cpu(attrptr->length);
  		blobptr += 2; /* advance attr size */
  		if (blobptr + attrsize > blobend)
  			break;
  		if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
  			if (!attrsize)
  				break;
  			if (!ses->domainName) {
  				ses->domainName =
  					kmalloc(attrsize + 1, GFP_KERNEL);
  				if (!ses->domainName)
  						return -ENOMEM;
  				cifs_from_ucs2(ses->domainName,
  					(__le16 *)blobptr, attrsize, attrsize,

  					nls_cp, false);

  				break;
  			}
  		}
  		blobptr += attrsize; /* advance attr  value */
  	}
  
  	return 0;
  }

  static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,

  			    const struct nls_table *nls_cp)

  {
  	int rc = 0;
  	int len;

  	char nt_hash[CIFS_NTHASH_SIZE];

  	wchar_t *user;
  	wchar_t *domain;

  	wchar_t *server;

  	if (!ses->server->secmech.sdeschmacmd5) {
  		cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash
  ");
  		return -1;
  	}

  	/* calculate md4 hash of password */

  	E_md4hash(ses->password, nt_hash, nls_cp);

  	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,

  				CIFS_NTHASH_SIZE);

  	if (rc) {
  		cERROR(1, "%s: Could not set NT Hash as a key", __func__);
  		return rc;
  	}

  
  	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
  	if (rc) {
  		cERROR(1, "calc_ntlmv2_hash: could not init hmacmd5
  ");
  		return rc;
  	}

  	/* convert ses->user_name to unicode and uppercase */
  	len = strlen(ses->user_name);

  	user = kmalloc(2 + (len * 2), GFP_KERNEL);

  	if (user == NULL) {
  		cERROR(1, "calc_ntlmv2_hash: user mem alloc failure
  ");
  		rc = -ENOMEM;

  		return rc;

  	}

  	len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp);

  	UniStrupr(user);

  	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,

  				(char *)user, 2 * len);

  	kfree(user);
  	if (rc) {
  		cERROR(1, "%s: Could not update with user
  ", __func__);
  		return rc;
  	}

  
  	/* convert ses->domainName to unicode and uppercase */

  	if (ses->domainName) {

  		len = strlen(ses->domainName);

  		domain = kmalloc(2 + (len * 2), GFP_KERNEL);

  		if (domain == NULL) {
  			cERROR(1, "calc_ntlmv2_hash: domain mem alloc failure");
  			rc = -ENOMEM;

  			return rc;

  		}

  		len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
  					nls_cp);

  		rc =

  		crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  					(char *)domain, 2 * len);

  		kfree(domain);

  		if (rc) {
  			cERROR(1, "%s: Could not update with domain
  ",
  								__func__);
  			return rc;
  		}

  	} else if (ses->serverName) {
  		len = strlen(ses->serverName);
  
  		server = kmalloc(2 + (len * 2), GFP_KERNEL);
  		if (server == NULL) {
  			cERROR(1, "calc_ntlmv2_hash: server mem alloc failure");
  			rc = -ENOMEM;

  			return rc;

  		}
  		len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
  					nls_cp);

  		rc =

  		crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  					(char *)server, 2 * len);
  		kfree(server);

  		if (rc) {
  			cERROR(1, "%s: Could not update with server
  ",
  								__func__);
  			return rc;
  		}

  	}

  
  	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,

  					ntlmv2_hash);

  	if (rc)
  		cERROR(1, "%s: Could not generate md5 hash
  ", __func__);

  	return rc;
  }
  
  static int

  CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)

  {
  	int rc;
  	unsigned int offset = CIFS_SESS_KEY_SIZE + 8;
  
  	if (!ses->server->secmech.sdeschmacmd5) {
  		cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash
  ");
  		return -1;
  	}

  	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,

  				ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);

  	if (rc) {
  		cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
  		return rc;
  	}

  
  	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
  	if (rc) {
  		cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
  		return rc;
  	}

  	if (ses->server->secType == RawNTLMSSP)
  		memcpy(ses->auth_key.response + offset,

  			ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);

  	else
  		memcpy(ses->auth_key.response + offset,
  			ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);

  	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,

  		ses->auth_key.response + offset, ses->auth_key.len - offset);

  	if (rc) {
  		cERROR(1, "%s: Could not update with response
  ", __func__);
  		return rc;
  	}

  
  	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
  		ses->auth_key.response + CIFS_SESS_KEY_SIZE);

  	if (rc)
  		cERROR(1, "%s: Could not generate md5 hash
  ", __func__);

  
  	return rc;
  }

  int

  setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)

  {

  	int rc;

  	int baselen;

  	unsigned int tilen;

  	struct ntlmv2_resp *buf;

  	char ntlmv2_hash[16];
  	unsigned char *tiblob = NULL; /* target info blob */

  	if (ses->server->secType == RawNTLMSSP) {
  		if (!ses->domainName) {

  			rc = find_domain_name(ses, nls_cp);

  			if (rc) {
  				cERROR(1, "error %d finding domain name", rc);
  				goto setup_ntlmv2_rsp_ret;
  			}
  		}
  	} else {

  		rc = build_avpair_blob(ses, nls_cp);

  		if (rc) {
  			cERROR(1, "error %d building av pair blob", rc);

  			goto setup_ntlmv2_rsp_ret;

  		}
  	}

  	baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);

  	tilen = ses->auth_key.len;
  	tiblob = ses->auth_key.response;
  
  	ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);

  	if (!ses->auth_key.response) {
  		rc = ENOMEM;

  		ses->auth_key.len = 0;

  		cERROR(1, "%s: Can't allocate auth blob", __func__);
  		goto setup_ntlmv2_rsp_ret;
  	}

  	ses->auth_key.len += baselen;

  
  	buf = (struct ntlmv2_resp *)
  			(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
  	buf->blob_signature = cpu_to_le32(0x00000101);
  	buf->reserved = 0;
  	buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
  	get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
  	buf->reserved2 = 0;

  	memcpy(ses->auth_key.response + baselen, tiblob, tilen);

  	/* calculate ntlmv2_hash */

  	rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);

  	if (rc) {

  		cERROR(1, "could not get v2 hash rc %d", rc);

  		goto setup_ntlmv2_rsp_ret;
  	}

  
  	/* calculate first part of the client response (CR1) */

  	rc = CalcNTLMv2_response(ses, ntlmv2_hash);

  	if (rc) {
  		cERROR(1, "Could not calculate CR1  rc: %d", rc);
  		goto setup_ntlmv2_rsp_ret;
  	}

  	/* now calculate the session key for NTLMv2 */

  	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,

  		ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);

  	if (rc) {
  		cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
  		goto setup_ntlmv2_rsp_ret;
  	}

  
  	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
  	if (rc) {
  		cERROR(1, "%s: Could not init hmacmd5
  ", __func__);
  		goto setup_ntlmv2_rsp_ret;
  	}

  	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,

  		ses->auth_key.response + CIFS_SESS_KEY_SIZE,
  		CIFS_HMAC_MD5_HASH_SIZE);

  	if (rc) {
  		cERROR(1, "%s: Could not update with response
  ", __func__);
  		goto setup_ntlmv2_rsp_ret;
  	}

  
  	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
  		ses->auth_key.response);

  	if (rc)
  		cERROR(1, "%s: Could not generate md5 hash
  ", __func__);

  setup_ntlmv2_rsp_ret:

  	kfree(tiblob);

  
  	return rc;

  }

  int

  calc_seckey(struct cifs_ses *ses)

  {
  	int rc;
  	struct crypto_blkcipher *tfm_arc4;
  	struct scatterlist sgin, sgout;
  	struct blkcipher_desc desc;
  	unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
  
  	get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
  
  	tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);

  	if (IS_ERR(tfm_arc4)) {
  		rc = PTR_ERR(tfm_arc4);

  		cERROR(1, "could not allocate crypto API arc4
  ");

  		return rc;

  	}
  
  	desc.tfm = tfm_arc4;

  	rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,

  					CIFS_SESS_KEY_SIZE);

  	if (rc) {
  		cERROR(1, "%s: Could not set response as a key", __func__);
  		return rc;
  	}

  
  	sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);

  	sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);

  
  	rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
  	if (rc) {
  		cERROR(1, "could not encrypt session key rc: %d
  ", rc);
  		crypto_free_blkcipher(tfm_arc4);
  		return rc;
  	}
  
  	/* make secondary_key/nonce as session key */
  	memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
  	/* and make len as that of session key only */
  	ses->auth_key.len = CIFS_SESS_KEY_SIZE;
  
  	crypto_free_blkcipher(tfm_arc4);

  	return rc;

  }
  
  void
  cifs_crypto_shash_release(struct TCP_Server_Info *server)
  {
  	if (server->secmech.md5)
  		crypto_free_shash(server->secmech.md5);
  
  	if (server->secmech.hmacmd5)
  		crypto_free_shash(server->secmech.hmacmd5);
  
  	kfree(server->secmech.sdeschmacmd5);
  
  	kfree(server->secmech.sdescmd5);
  }
  
  int
  cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
  {
  	int rc;
  	unsigned int size;
  
  	server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);

  	if (IS_ERR(server->secmech.hmacmd5)) {

  		cERROR(1, "could not allocate crypto hmacmd5
  ");
  		return PTR_ERR(server->secmech.hmacmd5);
  	}
  
  	server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);

  	if (IS_ERR(server->secmech.md5)) {

  		cERROR(1, "could not allocate crypto md5
  ");
  		rc = PTR_ERR(server->secmech.md5);
  		goto crypto_allocate_md5_fail;
  	}
  
  	size = sizeof(struct shash_desc) +
  			crypto_shash_descsize(server->secmech.hmacmd5);
  	server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
  	if (!server->secmech.sdeschmacmd5) {
  		cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5
  ");
  		rc = -ENOMEM;
  		goto crypto_allocate_hmacmd5_sdesc_fail;
  	}
  	server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
  	server->secmech.sdeschmacmd5->shash.flags = 0x0;
  
  
  	size = sizeof(struct shash_desc) +
  			crypto_shash_descsize(server->secmech.md5);
  	server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
  	if (!server->secmech.sdescmd5) {
  		cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5
  ");
  		rc = -ENOMEM;
  		goto crypto_allocate_md5_sdesc_fail;
  	}
  	server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
  	server->secmech.sdescmd5->shash.flags = 0x0;
  
  	return 0;
  
  crypto_allocate_md5_sdesc_fail:
  	kfree(server->secmech.sdeschmacmd5);
  
  crypto_allocate_hmacmd5_sdesc_fail:
  	crypto_free_shash(server->secmech.md5);
  
  crypto_allocate_md5_fail:
  	crypto_free_shash(server->secmech.hmacmd5);
  
  	return rc;
  }