fs/cifs/cifsencrypt.c - kernel/msm-4.9 - Gitiles

 /*
  *   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 "md5.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 */
 /* Note that the smb header signature field on input contains the
 	sequence number before this function is called */

 extern void mdfour(unsigned char *out, unsigned char *in, int n);
 extern void E_md4hash(const unsigned char *passwd, unsigned char *p16);
 extern void SMBencrypt(unsigned char *passwd, const unsigned char *c8,
 		       unsigned char *p24);

 static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
 			struct TCP_Server_Info *server, char *signature)
 {
 	int rc;

 	if (cifs_pdu == NULL || server == NULL || signature == NULL)
 		return -EINVAL;

 	if (!server->ntlmssp.sdescmd5) {
 		cERROR(1,
 			"cifs_calculate_signature: can't generate signature\n");
 		return -1;
 	}

 	rc = crypto_shash_init(&server->ntlmssp.sdescmd5->shash);
 	if (rc) {
 		cERROR(1, "cifs_calculate_signature: oould not init md5\n");
 		return rc;
 	}

 	if (server->secType == RawNTLMSSP)
 		crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 			server->session_key.data.ntlmv2.key,
 			CIFS_NTLMV2_SESSKEY_SIZE);
 	else
 		crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 			(char *)&server->session_key.data,
 			server->session_key.len);

 	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 			cifs_pdu->Protocol, cifs_pdu->smb_buf_length);

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

 	return rc;
 }


 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 		  __u32 *pexpected_response_sequence_number)
 {
 	int rc = 0;
 	char smb_signature[20];

 	if ((cifs_pdu == NULL) || (server == NULL))
 		return -EINVAL;

 	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
 		return rc;

 	spin_lock(&GlobalMid_Lock);
 	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++;
 	spin_unlock(&GlobalMid_Lock);

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

 	return rc;
 }

 static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
 			struct TCP_Server_Info *server, char *signature)
 {
 	int i;
 	int rc;

 	if (iov == NULL || server == NULL || signature == NULL)
 		return -EINVAL;

 	if (!server->ntlmssp.sdescmd5) {
 		cERROR(1, "cifs_calc_signature2: can't generate signature\n");
 		return -1;
 	}

 	rc = crypto_shash_init(&server->ntlmssp.sdescmd5->shash);
 	if (rc) {
 		cERROR(1, "cifs_calc_signature2: oould not init md5\n");
 		return rc;
 	}

 	if (server->secType == RawNTLMSSP)
 		crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 			server->session_key.data.ntlmv2.key,
 			CIFS_NTLMV2_SESSKEY_SIZE);
 	else
 		crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 			(char *)&server->session_key.data,
 			server->session_key.len);

 	for (i = 0; i < n_vec; i++) {
 		if (iov[i].iov_len == 0)
 			continue;
 		if (iov[i].iov_base == NULL) {
 			cERROR(1, "cifs_calc_signature2: 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 */
 			crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 				iov[i].iov_base + 4, iov[i].iov_len - 4);
 		} else
 			crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
 				iov[i].iov_base, iov[i].iov_len);
 	}

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

 	return rc;
 }

 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 = iov[0].iov_base;

 	if ((cifs_pdu == NULL) || (server == NULL))
 		return -EINVAL;

 	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
 		return rc;

 	spin_lock(&GlobalMid_Lock);
 	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++;
 	spin_unlock(&GlobalMid_Lock);

 	rc = cifs_calc_signature2(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;
 }

 int cifs_verify_signature(struct smb_hdr *cifs_pdu,
 			  struct TCP_Server_Info *server,
 			  __u32 expected_sequence_number)
 {
 	int rc;
 	char server_response_sig[8];
 	char what_we_think_sig_should_be[20];

 	if (cifs_pdu == NULL || server == NULL)
 		return -EINVAL;

 	if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
 		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;

 	rc = cifs_calculate_signature(cifs_pdu, server,
 		what_we_think_sig_should_be);

 	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;

 }

 /* We fill in key by putting in 40 byte array which was allocated by caller */
 int cifs_calculate_session_key(struct session_key *key, const char *rn,
 			   const char *password)
 {
 	char temp_key[16];
 	if ((key == NULL) || (rn == NULL))
 		return -EINVAL;

 	E_md4hash(password, temp_key);
 	mdfour(key->data.ntlm, temp_key, 16);
 	memcpy(key->data.ntlm+16, rn, CIFS_SESS_KEY_SIZE);
 	key->len = 40;
 	return 0;
 }

 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
 			char *lnm_session_key)
 {
 	int i;
 	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;
 	}

 	/* 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]);

 	SMBencrypt(password_with_pad, cryptkey, lnm_session_key);

 	/* clear password before we return/free memory */
 	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
 }
 #endif /* CIFS_WEAK_PW_HASH */

 static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
 			    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->ntlmssp.sdeschmacmd5) {
 		cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
 		return -1;
 	}

 	/* calculate md4 hash of password */
 	E_md4hash(ses->password, nt_hash);

 	crypto_shash_setkey(ses->server->ntlmssp.hmacmd5, nt_hash,
 				CIFS_NTHASH_SIZE);

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

 	/* convert ses->userName to unicode and uppercase */
 	len = strlen(ses->userName);
 	user = kmalloc(2 + (len * 2), GFP_KERNEL);
 	if (user == NULL) {
 		cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
 		rc = -ENOMEM;
 		goto calc_exit_2;
 	}
 	len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp);
 	UniStrupr(user);

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

 	/* 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;
 			goto calc_exit_1;
 		}
 		len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
 					nls_cp);
 		/* the following line was removed since it didn't work well
 		   with lower cased domain name that passed as an option.
 		   Maybe converting the domain name earlier makes sense */
 		/* UniStrupr(domain); */

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

 		kfree(domain);
 	} 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;
 			goto calc_exit_1;
 		}
 		len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
 					nls_cp);
 		/* the following line was removed since it didn't work well
 		   with lower cased domain name that passed as an option.
 		   Maybe converting the domain name earlier makes sense */
 		/* UniStrupr(domain); */

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

 		kfree(server);
 	}

 	rc = crypto_shash_final(&ses->server->ntlmssp.sdeschmacmd5->shash,
 					ses->server->ntlmv2_hash);

 calc_exit_1:
 	kfree(user);
 calc_exit_2:
 	/* BB FIXME what about bytes 24 through 40 of the signing key?
 	   compare with the NTLM example */

 	return rc;
 }

 static int
 find_domain_name(struct cifsSesInfo *ses)
 {
 	int rc = 0;
 	unsigned int attrsize;
 	unsigned int type;
 	unsigned char *blobptr;
 	struct ntlmssp2_name *attrptr;

 	if (ses->server->tiblob) {
 		blobptr = ses->server->tiblob;
 		attrptr = (struct ntlmssp2_name *) blobptr;

 		while ((type = attrptr->type) != 0) {
 			blobptr += 2; /* advance attr type */
 			attrsize = attrptr->length;
 			blobptr += 2; /* advance attr size */
 			if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
 				if (!ses->domainName) {
 					ses->domainName =
 						kmalloc(attrptr->length + 1,
 								GFP_KERNEL);
 					if (!ses->domainName)
 							return -ENOMEM;
 					cifs_from_ucs2(ses->domainName,
 						(__le16 *)blobptr,
 						attrptr->length,
 						attrptr->length,
 						load_nls_default(), false);
 				}
 			}
 			blobptr += attrsize; /* advance attr  value */
 			attrptr = (struct ntlmssp2_name *) blobptr;
 		}
 	} else {
 		ses->server->tilen = 2 * sizeof(struct ntlmssp2_name);
 		ses->server->tiblob = kmalloc(ses->server->tilen, GFP_KERNEL);
 		if (!ses->server->tiblob) {
 			ses->server->tilen = 0;
 			cERROR(1, "Challenge target info allocation failure");
 			return -ENOMEM;
 		}
 		memset(ses->server->tiblob, 0x0, ses->server->tilen);
 		attrptr = (struct ntlmssp2_name *) ses->server->tiblob;
 		attrptr->type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE);
 	}

 	return rc;
 }

 static int
 CalcNTLMv2_response(const struct TCP_Server_Info *server,
 			 char *v2_session_response)
 {
 	int rc;

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

 	crypto_shash_setkey(server->ntlmssp.hmacmd5, server->ntlmv2_hash,
 		CIFS_HMAC_MD5_HASH_SIZE);

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

 	memcpy(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
 		server->cryptKey, CIFS_SERVER_CHALLENGE_SIZE);
 	crypto_shash_update(&server->ntlmssp.sdeschmacmd5->shash,
 		v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
 		sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE);

 	if (server->tilen)
 		crypto_shash_update(&server->ntlmssp.sdeschmacmd5->shash,
 					server->tiblob, server->tilen);

 	rc = crypto_shash_final(&server->ntlmssp.sdeschmacmd5->shash,
 					v2_session_response);

 	return rc;
 }

 int
 setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
 		      const struct nls_table *nls_cp)
 {
 	int rc = 0;
 	struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;

 	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;

 	if (!ses->domainName) {
 		rc = find_domain_name(ses);
 		if (rc) {
 			cERROR(1, "could not get domain/server name rc %d", rc);
 			return rc;
 		}
 	}

 	/* calculate buf->ntlmv2_hash */
 	rc = calc_ntlmv2_hash(ses, nls_cp);
 	if (rc) {
 		cERROR(1, "could not get v2 hash rc %d", rc);
 		return rc;
 	}
 	rc = CalcNTLMv2_response(ses->server, resp_buf);
 	if (rc) {
 		cERROR(1, "could not get v2 hash rc %d", rc);
 		return rc;
 	}

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

 	crypto_shash_setkey(ses->server->ntlmssp.hmacmd5,
 			ses->server->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);

 	rc = crypto_shash_init(&ses->server->ntlmssp.sdeschmacmd5->shash);
 	if (rc) {
 		cERROR(1, "setup_ntlmv2_rsp: could not init hmacmd5\n");
 		return rc;
 	}

 	crypto_shash_update(&ses->server->ntlmssp.sdeschmacmd5->shash,
 				resp_buf, CIFS_HMAC_MD5_HASH_SIZE);

 	rc = crypto_shash_final(&ses->server->ntlmssp.sdeschmacmd5->shash,
 		ses->server->session_key.data.ntlmv2.key);

 	memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
 			sizeof(struct ntlmv2_resp));
 	ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);

 	return rc;
 }

 int
 calc_seckey(struct TCP_Server_Info *server)
 {
 	int rc;
 	unsigned char sec_key[CIFS_NTLMV2_SESSKEY_SIZE];
 	struct crypto_blkcipher *tfm_arc4;
 	struct scatterlist sgin, sgout;
 	struct blkcipher_desc desc;

 	get_random_bytes(sec_key, CIFS_NTLMV2_SESSKEY_SIZE);

 	tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)",
 						0, CRYPTO_ALG_ASYNC);
 	if (!tfm_arc4 || IS_ERR(tfm_arc4)) {
 		cERROR(1, "could not allocate " "master crypto API arc4\n");
 		return 1;
 	}

 	desc.tfm = tfm_arc4;

 	crypto_blkcipher_setkey(tfm_arc4,
 		server->session_key.data.ntlmv2.key, CIFS_CPHTXT_SIZE);
 	sg_init_one(&sgin, sec_key, CIFS_CPHTXT_SIZE);
 	sg_init_one(&sgout, server->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE);
 	rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);

 	if (!rc)
 		memcpy(server->session_key.data.ntlmv2.key,
 				sec_key, CIFS_NTLMV2_SESSKEY_SIZE);

 	crypto_free_blkcipher(tfm_arc4);

 	return 0;
 }

 void
 cifs_crypto_shash_release(struct TCP_Server_Info *server)
 {
 	if (server->ntlmssp.md5)
 		crypto_free_shash(server->ntlmssp.md5);

 	if (server->ntlmssp.hmacmd5)
 		crypto_free_shash(server->ntlmssp.hmacmd5);

 	kfree(server->ntlmssp.sdeschmacmd5);

 	kfree(server->ntlmssp.sdescmd5);
 }

 int
 cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
 {
 	int rc;
 	unsigned int size;

 	server->ntlmssp.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
 	if (!server->ntlmssp.hmacmd5 ||
 			IS_ERR(server->ntlmssp.hmacmd5)) {
 		cERROR(1, "could not allocate crypto hmacmd5\n");
 		return 1;
 	}

 	server->ntlmssp.md5 = crypto_alloc_shash("md5", 0, 0);
 	if (!server->ntlmssp.md5 || IS_ERR(server->ntlmssp.md5)) {
 		cERROR(1, "could not allocate crypto md5\n");
 		rc = 1;
 		goto cifs_crypto_shash_allocate_ret1;
 	}

 	size = sizeof(struct shash_desc) +
 			crypto_shash_descsize(server->ntlmssp.hmacmd5);
 	server->ntlmssp.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
 	if (!server->ntlmssp.sdeschmacmd5) {
 		cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
 		rc = -ENOMEM;
 		goto cifs_crypto_shash_allocate_ret2;
 	}
 	server->ntlmssp.sdeschmacmd5->shash.tfm = server->ntlmssp.hmacmd5;
 	server->ntlmssp.sdeschmacmd5->shash.flags = 0x0;


 	size = sizeof(struct shash_desc) +
 			crypto_shash_descsize(server->ntlmssp.md5);
 	server->ntlmssp.sdescmd5 = kmalloc(size, GFP_KERNEL);
 	if (!server->ntlmssp.sdescmd5) {
 		cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
 		rc = -ENOMEM;
 		goto cifs_crypto_shash_allocate_ret3;
 	}
 	server->ntlmssp.sdescmd5->shash.tfm = server->ntlmssp.md5;
 	server->ntlmssp.sdescmd5->shash.flags = 0x0;

 	return 0;

 cifs_crypto_shash_allocate_ret3:
 	kfree(server->ntlmssp.sdeschmacmd5);

 cifs_crypto_shash_allocate_ret2:
 	crypto_free_shash(server->ntlmssp.md5);

 cifs_crypto_shash_allocate_ret1:
 	crypto_free_shash(server->ntlmssp.hmacmd5);

 	return rc;
 }
	/*
	* 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 "md5.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 */
	/* Note that the smb header signature field on input contains the
	sequence number before this function is called */

	extern void mdfour(unsigned char out, unsigned char in, int n);
	extern void E_md4hash(const unsigned char passwd, unsigned char p16);
	extern void SMBencrypt(unsigned char passwd, const unsigned char c8,
	unsigned char *p24);

	static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
	struct TCP_Server_Info server, char signature)
	{
	int rc;

	if (cifs_pdu == NULL \|\| server == NULL \|\| signature == NULL)
	return -EINVAL;

	if (!server->ntlmssp.sdescmd5) {
	cERROR(1,
	"cifs_calculate_signature: can't generate signature\n");
	return -1;
	}

	rc = crypto_shash_init(&server->ntlmssp.sdescmd5->shash);
	if (rc) {
	cERROR(1, "cifs_calculate_signature: oould not init md5\n");
	return rc;
	}

	if (server->secType == RawNTLMSSP)
	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	server->session_key.data.ntlmv2.key,
	CIFS_NTLMV2_SESSKEY_SIZE);
	else
	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	(char *)&server->session_key.data,
	server->session_key.len);

	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	cifs_pdu->Protocol, cifs_pdu->smb_buf_length);

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

	return rc;
	}


	int cifs_sign_smb(struct smb_hdr cifs_pdu, struct TCP_Server_Info server,
	__u32 *pexpected_response_sequence_number)
	{
	int rc = 0;
	char smb_signature[20];

	if ((cifs_pdu == NULL) \|\| (server == NULL))
	return -EINVAL;

	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
	return rc;

	spin_lock(&GlobalMid_Lock);
	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++;
	spin_unlock(&GlobalMid_Lock);

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

	return rc;
	}

	static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
	struct TCP_Server_Info server, char signature)
	{
	int i;
	int rc;

	if (iov == NULL \|\| server == NULL \|\| signature == NULL)
	return -EINVAL;

	if (!server->ntlmssp.sdescmd5) {
	cERROR(1, "cifs_calc_signature2: can't generate signature\n");
	return -1;
	}

	rc = crypto_shash_init(&server->ntlmssp.sdescmd5->shash);
	if (rc) {
	cERROR(1, "cifs_calc_signature2: oould not init md5\n");
	return rc;
	}

	if (server->secType == RawNTLMSSP)
	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	server->session_key.data.ntlmv2.key,
	CIFS_NTLMV2_SESSKEY_SIZE);
	else
	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	(char *)&server->session_key.data,
	server->session_key.len);

	for (i = 0; i < n_vec; i++) {
	if (iov[i].iov_len == 0)
	continue;
	if (iov[i].iov_base == NULL) {
	cERROR(1, "cifs_calc_signature2: 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 */
	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	iov[i].iov_base + 4, iov[i].iov_len - 4);
	} else
	crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
	iov[i].iov_base, iov[i].iov_len);
	}

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

	return rc;
	}

	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 = iov[0].iov_base;

	if ((cifs_pdu == NULL) \|\| (server == NULL))
	return -EINVAL;

	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
	return rc;

	spin_lock(&GlobalMid_Lock);
	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++;
	spin_unlock(&GlobalMid_Lock);

	rc = cifs_calc_signature2(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;
	}

	int cifs_verify_signature(struct smb_hdr *cifs_pdu,
	struct TCP_Server_Info *server,
	__u32 expected_sequence_number)
	{
	int rc;
	char server_response_sig[8];
	char what_we_think_sig_should_be[20];

	if (cifs_pdu == NULL \|\| server == NULL)
	return -EINVAL;

	if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
	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;

	rc = cifs_calculate_signature(cifs_pdu, server,
	what_we_think_sig_should_be);

	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;

	}

	/* We fill in key by putting in 40 byte array which was allocated by caller */
	int cifs_calculate_session_key(struct session_key key, const char rn,
	const char *password)
	{
	char temp_key[16];
	if ((key == NULL) \|\| (rn == NULL))
	return -EINVAL;

	E_md4hash(password, temp_key);
	mdfour(key->data.ntlm, temp_key, 16);
	memcpy(key->data.ntlm+16, rn, CIFS_SESS_KEY_SIZE);
	key->len = 40;
	return 0;
	}

	#ifdef CONFIG_CIFS_WEAK_PW_HASH
	void calc_lanman_hash(const char password, const char cryptkey, bool encrypt,
	char *lnm_session_key)
	{
	int i;
	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;
	}

	/* 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]);

	SMBencrypt(password_with_pad, cryptkey, lnm_session_key);

	/* clear password before we return/free memory */
	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
	}
	#endif /* CIFS_WEAK_PW_HASH */

	static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
	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->ntlmssp.sdeschmacmd5) {
	cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
	return -1;
	}

	/* calculate md4 hash of password */
	E_md4hash(ses->password, nt_hash);

	crypto_shash_setkey(ses->server->ntlmssp.hmacmd5, nt_hash,
	CIFS_NTHASH_SIZE);

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

	/* convert ses->userName to unicode and uppercase */
	len = strlen(ses->userName);
	user = kmalloc(2 + (len * 2), GFP_KERNEL);
	if (user == NULL) {
	cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
	rc = -ENOMEM;
	goto calc_exit_2;
	}
	len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp);
	UniStrupr(user);

	crypto_shash_update(&ses->server->ntlmssp.sdeschmacmd5->shash,
	(char )user, 2 len);

	/* 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;
	goto calc_exit_1;
	}
	len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
	nls_cp);
	/* the following line was removed since it didn't work well
	with lower cased domain name that passed as an option.
	Maybe converting the domain name earlier makes sense */
	/* UniStrupr(domain); */

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

	kfree(domain);
	} 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;
	goto calc_exit_1;
	}
	len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
	nls_cp);
	/* the following line was removed since it didn't work well
	with lower cased domain name that passed as an option.
	Maybe converting the domain name earlier makes sense */
	/* UniStrupr(domain); */

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

	kfree(server);
	}

	rc = crypto_shash_final(&ses->server->ntlmssp.sdeschmacmd5->shash,
	ses->server->ntlmv2_hash);

	calc_exit_1:
	kfree(user);
	calc_exit_2:
	/* BB FIXME what about bytes 24 through 40 of the signing key?
	compare with the NTLM example */

	return rc;
	}

	static int
	find_domain_name(struct cifsSesInfo *ses)
	{
	int rc = 0;
	unsigned int attrsize;
	unsigned int type;
	unsigned char *blobptr;
	struct ntlmssp2_name *attrptr;

	if (ses->server->tiblob) {
	blobptr = ses->server->tiblob;
	attrptr = (struct ntlmssp2_name *) blobptr;

	while ((type = attrptr->type) != 0) {
	blobptr += 2; /* advance attr type */
	attrsize = attrptr->length;
	blobptr += 2; /* advance attr size */
	if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
	if (!ses->domainName) {
	ses->domainName =
	kmalloc(attrptr->length + 1,
	GFP_KERNEL);
	if (!ses->domainName)
	return -ENOMEM;
	cifs_from_ucs2(ses->domainName,
	(__le16 *)blobptr,
	attrptr->length,
	attrptr->length,
	load_nls_default(), false);
	}
	}
	blobptr += attrsize; /* advance attr value */
	attrptr = (struct ntlmssp2_name *) blobptr;
	}
	} else {
	ses->server->tilen = 2 * sizeof(struct ntlmssp2_name);
	ses->server->tiblob = kmalloc(ses->server->tilen, GFP_KERNEL);
	if (!ses->server->tiblob) {
	ses->server->tilen = 0;
	cERROR(1, "Challenge target info allocation failure");
	return -ENOMEM;
	}
	memset(ses->server->tiblob, 0x0, ses->server->tilen);
	attrptr = (struct ntlmssp2_name *) ses->server->tiblob;
	attrptr->type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE);
	}

	return rc;
	}

	static int
	CalcNTLMv2_response(const struct TCP_Server_Info *server,
	char *v2_session_response)
	{
	int rc;

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

	crypto_shash_setkey(server->ntlmssp.hmacmd5, server->ntlmv2_hash,
	CIFS_HMAC_MD5_HASH_SIZE);

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

	memcpy(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
	server->cryptKey, CIFS_SERVER_CHALLENGE_SIZE);
	crypto_shash_update(&server->ntlmssp.sdeschmacmd5->shash,
	v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
	sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE);

	if (server->tilen)
	crypto_shash_update(&server->ntlmssp.sdeschmacmd5->shash,
	server->tiblob, server->tilen);

	rc = crypto_shash_final(&server->ntlmssp.sdeschmacmd5->shash,
	v2_session_response);

	return rc;
	}

	int
	setup_ntlmv2_rsp(struct cifsSesInfo ses, char resp_buf,
	const struct nls_table *nls_cp)
	{
	int rc = 0;
	struct ntlmv2_resp buf = (struct ntlmv2_resp )resp_buf;

	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;

	if (!ses->domainName) {
	rc = find_domain_name(ses);
	if (rc) {
	cERROR(1, "could not get domain/server name rc %d", rc);
	return rc;
	}
	}

	/* calculate buf->ntlmv2_hash */
	rc = calc_ntlmv2_hash(ses, nls_cp);
	if (rc) {
	cERROR(1, "could not get v2 hash rc %d", rc);
	return rc;
	}
	rc = CalcNTLMv2_response(ses->server, resp_buf);
	if (rc) {
	cERROR(1, "could not get v2 hash rc %d", rc);
	return rc;
	}

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

	crypto_shash_setkey(ses->server->ntlmssp.hmacmd5,
	ses->server->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);

	rc = crypto_shash_init(&ses->server->ntlmssp.sdeschmacmd5->shash);
	if (rc) {
	cERROR(1, "setup_ntlmv2_rsp: could not init hmacmd5\n");
	return rc;
	}

	crypto_shash_update(&ses->server->ntlmssp.sdeschmacmd5->shash,
	resp_buf, CIFS_HMAC_MD5_HASH_SIZE);

	rc = crypto_shash_final(&ses->server->ntlmssp.sdeschmacmd5->shash,
	ses->server->session_key.data.ntlmv2.key);

	memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
	sizeof(struct ntlmv2_resp));
	ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);

	return rc;
	}

	int
	calc_seckey(struct TCP_Server_Info *server)
	{
	int rc;
	unsigned char sec_key[CIFS_NTLMV2_SESSKEY_SIZE];
	struct crypto_blkcipher *tfm_arc4;
	struct scatterlist sgin, sgout;
	struct blkcipher_desc desc;

	get_random_bytes(sec_key, CIFS_NTLMV2_SESSKEY_SIZE);

	tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)",
	0, CRYPTO_ALG_ASYNC);
	if (!tfm_arc4 \|\| IS_ERR(tfm_arc4)) {
	cERROR(1, "could not allocate " "master crypto API arc4\n");
	return 1;
	}

	desc.tfm = tfm_arc4;

	crypto_blkcipher_setkey(tfm_arc4,
	server->session_key.data.ntlmv2.key, CIFS_CPHTXT_SIZE);
	sg_init_one(&sgin, sec_key, CIFS_CPHTXT_SIZE);
	sg_init_one(&sgout, server->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE);
	rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);

	if (!rc)
	memcpy(server->session_key.data.ntlmv2.key,
	sec_key, CIFS_NTLMV2_SESSKEY_SIZE);

	crypto_free_blkcipher(tfm_arc4);

	return 0;
	}

	void
	cifs_crypto_shash_release(struct TCP_Server_Info *server)
	{
	if (server->ntlmssp.md5)
	crypto_free_shash(server->ntlmssp.md5);

	if (server->ntlmssp.hmacmd5)
	crypto_free_shash(server->ntlmssp.hmacmd5);

	kfree(server->ntlmssp.sdeschmacmd5);

	kfree(server->ntlmssp.sdescmd5);
	}

	int
	cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
	{
	int rc;
	unsigned int size;

	server->ntlmssp.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
	if (!server->ntlmssp.hmacmd5 \|\|
	IS_ERR(server->ntlmssp.hmacmd5)) {
	cERROR(1, "could not allocate crypto hmacmd5\n");
	return 1;
	}

	server->ntlmssp.md5 = crypto_alloc_shash("md5", 0, 0);
	if (!server->ntlmssp.md5 \|\| IS_ERR(server->ntlmssp.md5)) {
	cERROR(1, "could not allocate crypto md5\n");
	rc = 1;
	goto cifs_crypto_shash_allocate_ret1;
	}

	size = sizeof(struct shash_desc) +
	crypto_shash_descsize(server->ntlmssp.hmacmd5);
	server->ntlmssp.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
	if (!server->ntlmssp.sdeschmacmd5) {
	cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
	rc = -ENOMEM;
	goto cifs_crypto_shash_allocate_ret2;
	}
	server->ntlmssp.sdeschmacmd5->shash.tfm = server->ntlmssp.hmacmd5;
	server->ntlmssp.sdeschmacmd5->shash.flags = 0x0;


	size = sizeof(struct shash_desc) +
	crypto_shash_descsize(server->ntlmssp.md5);
	server->ntlmssp.sdescmd5 = kmalloc(size, GFP_KERNEL);
	if (!server->ntlmssp.sdescmd5) {
	cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
	rc = -ENOMEM;
	goto cifs_crypto_shash_allocate_ret3;
	}
	server->ntlmssp.sdescmd5->shash.tfm = server->ntlmssp.md5;
	server->ntlmssp.sdescmd5->shash.flags = 0x0;

	return 0;

	cifs_crypto_shash_allocate_ret3:
	kfree(server->ntlmssp.sdeschmacmd5);

	cifs_crypto_shash_allocate_ret2:
	crypto_free_shash(server->ntlmssp.md5);

	cifs_crypto_shash_allocate_ret1:
	crypto_free_shash(server->ntlmssp.hmacmd5);

	return rc;
	}