[mirror_ubuntu-artful-kernel.git] / fs / cifs / cifsencrypt.c

/*
 *   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,
				const struct session_key *key, char *signature)
{
	struct	MD5Context context;

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

	cifs_MD5_init(&context);
	cifs_MD5_update(&context, (char *)&key->data, key->len);
	cifs_MD5_update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length);

	cifs_MD5_final(signature, &context);
	return 0;
}

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->session_key,
				      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,
				const struct session_key *key, char *signature)
{
	struct  MD5Context context;
	int i;

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

	cifs_MD5_init(&context);
	cifs_MD5_update(&context, (char *)&key->data, key->len);
	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 */
			cifs_MD5_update(&context, iov[0].iov_base+4,
				  iov[0].iov_len-4);
		} else
			cifs_MD5_update(&context, iov[i].iov_base, iov[i].iov_len);
	}

	cifs_MD5_final(signature, &context);

	return 0;
}


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->session_key,
				      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,
			  const struct session_key *session_key,
			  __u32 expected_sequence_number)
{
	unsigned int rc;
	char server_response_sig[8];
	char what_we_think_sig_should_be[20];

	if (cifs_pdu == NULL || session_key == 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, session_key,
		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 */

/* 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 cifsSesInfo *ses, const struct nls_table *nls_cp)
{
	unsigned int dlen;
	unsigned int wlen;
	unsigned int size = 6 * sizeof(struct ntlmssp2_name);
	__le64  curtime;
	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);
	wlen = strlen(ses->server->hostname);

	/* The length of this blob is a size which is
	 * six times the size of a structure which holds name/size +
	 * two times the unicode length of a domain name +
	 * two times the unicode length of a server name +
	 * size of a timestamp (which is 8 bytes).
	 */
	ses->tilen = size + 2 * (2 * dlen) + 2 * (2 * wlen) + 8;
	ses->tiblob = kzalloc(ses->tilen, GFP_KERNEL);
	if (!ses->tiblob) {
		ses->tilen = 0;
		cERROR(1, "Challenge target info allocation failure");
		return -ENOMEM;
	}

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

	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);

	blobptr += 2 * dlen;
	attrptr = (struct ntlmssp2_name *) blobptr;

	attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_COMPUTER_NAME);
	attrptr->length = cpu_to_le16(2 * wlen);
	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);

	blobptr += 2 * wlen;
	attrptr = (struct ntlmssp2_name *) blobptr;

	attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_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);

	blobptr += 2 * dlen;
	attrptr = (struct ntlmssp2_name *) blobptr;

	attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_COMPUTER_NAME);
	attrptr->length = cpu_to_le16(2 * wlen);
	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);

	blobptr += 2 * wlen;
	attrptr = (struct ntlmssp2_name *) blobptr;

	attrptr->type = cpu_to_le16(NTLMSSP_AV_TIMESTAMP);
	attrptr->length = cpu_to_le16(sizeof(__le64));
	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	curtime = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
	memcpy(blobptr, &curtime, sizeof(__le64));

	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 cifsSesInfo *ses)
{
	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->tilen || !ses->tiblob)
		return 0;

	blobptr = ses->tiblob;
	blobend = ses->tiblob + ses->tilen;

	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) {
				struct nls_table *default_nls;
				ses->domainName =
					kmalloc(attrsize + 1, GFP_KERNEL);
				if (!ses->domainName)
						return -ENOMEM;
				default_nls = load_nls_default();
				cifs_from_ucs2(ses->domainName,
					(__le16 *)blobptr, attrsize, attrsize,
					default_nls, false);
				unload_nls(default_nls);
				break;
			}
		}
		blobptr += attrsize; /* advance attr  value */
	}

	return 0;
}

static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
			    const struct nls_table *nls_cp)
{
	int rc = 0;
	int len;
	char nt_hash[16];
	struct HMACMD5Context *pctxt;
	wchar_t *user;
	wchar_t *domain;

	pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);

	if (pctxt == NULL)
		return -ENOMEM;

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

	/* convert Domainname to unicode and uppercase */
	hmac_md5_init_limK_to_64(nt_hash, 16, pctxt);

	/* convert ses->userName to unicode and uppercase */
	len = strlen(ses->userName);
	user = kmalloc(2 + (len * 2), GFP_KERNEL);
	if (user == NULL)
		goto calc_exit_2;
	len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp);
	UniStrupr(user);
	hmac_md5_update((char *)user, 2*len, pctxt);

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

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

		hmac_md5_update((char *)domain, 2*len, pctxt);

		kfree(domain);
	}
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 */
	hmac_md5_final(ses->server->ntlmv2_hash, pctxt);

	kfree(pctxt);
	return rc;
}

int
setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
		      const struct nls_table *nls_cp)
{
	int rc;
	struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;
	struct HMACMD5Context context;

	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->server->secType == RawNTLMSSP) {
		if (!ses->domainName) {
			rc = find_domain_name(ses);
			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);
			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);
		goto setup_ntlmv2_rsp_ret;
	}
	CalcNTLMv2_response(ses, resp_buf);

	/* now calculate the MAC key for NTLMv2 */
	hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
	hmac_md5_update(resp_buf, 16, &context);
	hmac_md5_final(ses->server->session_key.data.ntlmv2.key, &context);

	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 0;

setup_ntlmv2_rsp_ret:
	kfree(ses->tiblob);
	ses->tiblob = NULL;
	ses->tilen = 0;

	return rc;
}

void CalcNTLMv2_response(const struct cifsSesInfo *ses,
			 char *v2_session_response)
{
	struct HMACMD5Context context;
	/* rest of v2 struct already generated */
	memcpy(v2_session_response + 8, ses->server->cryptKey, 8);
	hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);

	hmac_md5_update(v2_session_response+8,
			sizeof(struct ntlmv2_resp) - 8, &context);

	if (ses->tilen)
		hmac_md5_update(ses->tiblob, ses->tilen, &context);

	hmac_md5_final(v2_session_response, &context);
/*	cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* fs/cifs/cifsencrypt.c
	3	*
12b3b8ff	4	* Copyright (C) International Business Machines Corp., 2005,2006
1da177e4 LT	5	* Author(s): Steve French (sfrench@us.ibm.com)
	6	*
	7	* This library is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU Lesser General Public License as published
	9	* by the Free Software Foundation; either version 2.1 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This library is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	15	* the GNU Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public License
	18	* along with this library; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21
	22	#include <linux/fs.h>
5a0e3ad6	23	#include <linux/slab.h>
1da177e4	24	#include "cifspdu.h"
ffdd6e4d	25	#include "cifsglob.h"
1da177e4 LT	26	#include "cifs_debug.h"
	27	#include "md5.h"
	28	#include "cifs_unicode.h"
	29	#include "cifsproto.h"
2b149f11	30	#include "ntlmssp.h"
7c7b25bc	31	#include <linux/ctype.h>
6d027cfd	32	#include <linux/random.h>
1da177e4	33
ffdd6e4d	34	/* Calculate and return the CIFS signature based on the mac key and SMB PDU */
1da177e4 LT	35	/* the 16 byte signature must be allocated by the caller */
1da177e4 LT	36	/* Note we only use the 1st eight bytes */
ffdd6e4d	37	/* Note that the smb header signature field on input contains the
1da177e4 LT	38	sequence number before this function is called */
	39
	40	extern void mdfour(unsigned char out, unsigned char in, int n);
	41	extern void E_md4hash(const unsigned char passwd, unsigned char p16);
4e53a3fb	42	extern void SMBencrypt(unsigned char passwd, const unsigned char c8,
ffdd6e4d	43	unsigned char *p24);
50c2f753	44
ffdd6e4d	45	static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
5f98ca9a	46	const struct session_key key, char signature)
1da177e4	47	{
c8e56f1f	48	struct MD5Context context;
1da177e4	49
c8e56f1f	50	if ((cifs_pdu == NULL) \|\| (signature == NULL) \|\| (key == NULL))
1da177e4 LT	51	return -EINVAL;
1da177e4 LT	52
c8e56f1f SF	53	cifs_MD5_init(&context);
	54	cifs_MD5_update(&context, (char *)&key->data, key->len);
	55	cifs_MD5_update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length);
b609f06a	56
c8e56f1f	57	cifs_MD5_final(signature, &context);
56234e27	58	return 0;
1da177e4 LT	59	}
1da177e4 LT	60
ffdd6e4d SF	61	int cifs_sign_smb(struct smb_hdr cifs_pdu, struct TCP_Server_Info server,
ffdd6e4d SF	62	__u32 *pexpected_response_sequence_number)
1da177e4 LT	63	{
	64	int rc = 0;
	65	char smb_signature[20];
	66
ffdd6e4d	67	if ((cifs_pdu == NULL) \|\| (server == NULL))
1da177e4 LT	68	return -EINVAL;
1da177e4 LT	69
ffdd6e4d	70	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
1da177e4 LT	71	return rc;
	72
	73	spin_lock(&GlobalMid_Lock);
50c2f753 SF	74	cifs_pdu->Signature.Sequence.SequenceNumber =
50c2f753 SF	75	cpu_to_le32(server->sequence_number);
1da177e4	76	cifs_pdu->Signature.Sequence.Reserved = 0;
50c2f753	77
ad009ac9 SF	78	*pexpected_response_sequence_number = server->sequence_number++;
ad009ac9 SF	79	server->sequence_number++;
1da177e4 LT	80	spin_unlock(&GlobalMid_Lock);
1da177e4 LT	81
5f98ca9a	82	rc = cifs_calculate_signature(cifs_pdu, &server->session_key,
c8e56f1f	83	smb_signature);
ffdd6e4d	84	if (rc)
1da177e4 LT	85	memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
	86	else
	87	memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
	88
	89	return rc;
	90	}
	91
ffdd6e4d	92	static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
5f98ca9a	93	const struct session_key key, char signature)
84afc29b	94	{
c8e56f1f	95	struct MD5Context context;
e9917a00	96	int i;
84afc29b	97
c8e56f1f	98	if ((iov == NULL) \|\| (signature == NULL) \|\| (key == NULL))
e9917a00	99	return -EINVAL;
84afc29b	100
c8e56f1f SF	101	cifs_MD5_init(&context);
c8e56f1f SF	102	cifs_MD5_update(&context, (char *)&key->data, key->len);
50c2f753	103	for (i = 0; i < n_vec; i++) {
745542e2 JL	104	if (iov[i].iov_len == 0)
745542e2 JL	105	continue;
ffdd6e4d	106	if (iov[i].iov_base == NULL) {
56234e27	107	cERROR(1, "null iovec entry");
e9917a00	108	return -EIO;
745542e2	109	}
ffdd6e4d	110	/* The first entry includes a length field (which does not get
e9917a00	111	signed that occupies the first 4 bytes before the header */
ffdd6e4d	112	if (i == 0) {
63d2583f	113	if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
e9917a00	114	break; /* nothing to sign or corrupt header */
c8e56f1f SF	115	cifs_MD5_update(&context, iov[0].iov_base+4,
c8e56f1f SF	116	iov[0].iov_len-4);
e9917a00	117	} else
c8e56f1f	118	cifs_MD5_update(&context, iov[i].iov_base, iov[i].iov_len);
e9917a00	119	}
84afc29b	120
c8e56f1f	121	cifs_MD5_final(signature, &context);
84afc29b	122
56234e27	123	return 0;
84afc29b SF	124	}
84afc29b SF	125
c8e56f1f	126
ffdd6e4d	127	int cifs_sign_smb2(struct kvec iov, int n_vec, struct TCP_Server_Info server,
63d2583f	128	__u32 *pexpected_response_sequence_number)
84afc29b SF	129	{
	130	int rc = 0;
	131	char smb_signature[20];
ffdd6e4d	132	struct smb_hdr *cifs_pdu = iov[0].iov_base;
84afc29b	133
ffdd6e4d	134	if ((cifs_pdu == NULL) \|\| (server == NULL))
84afc29b SF	135	return -EINVAL;
84afc29b SF	136
ffdd6e4d	137	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
84afc29b SF	138	return rc;
84afc29b SF	139
ffdd6e4d SF	140	spin_lock(&GlobalMid_Lock);
ffdd6e4d SF	141	cifs_pdu->Signature.Sequence.SequenceNumber =
84afc29b	142	cpu_to_le32(server->sequence_number);
ffdd6e4d	143	cifs_pdu->Signature.Sequence.Reserved = 0;
84afc29b	144
ffdd6e4d SF	145	*pexpected_response_sequence_number = server->sequence_number++;
	146	server->sequence_number++;
	147	spin_unlock(&GlobalMid_Lock);
84afc29b	148
5f98ca9a	149	rc = cifs_calc_signature2(iov, n_vec, &server->session_key,
c8e56f1f	150	smb_signature);
ffdd6e4d SF	151	if (rc)
	152	memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
	153	else
	154	memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
84afc29b	155
ffdd6e4d	156	return rc;
84afc29b SF	157	}
84afc29b SF	158
b609f06a	159	int cifs_verify_signature(struct smb_hdr *cifs_pdu,
5f98ca9a	160	const struct session_key *session_key,
ffdd6e4d	161	__u32 expected_sequence_number)
1da177e4	162	{
c8e56f1f	163	unsigned int rc;
1da177e4 LT	164	char server_response_sig[8];
	165	char what_we_think_sig_should_be[20];
	166
5f98ca9a	167	if (cifs_pdu == NULL \|\| session_key == NULL)
1da177e4 LT	168	return -EINVAL;
	169
	170	if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
	171	return 0;
	172
	173	if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
50c2f753	174	struct smb_com_lock_req *pSMB =
ffdd6e4d SF	175	(struct smb_com_lock_req *)cifs_pdu;
ffdd6e4d SF	176	if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
1da177e4 LT	177	return 0;
	178	}
	179
50c2f753 SF	180	/* BB what if signatures are supposed to be on for session but
	181	server does not send one? BB */
	182
1da177e4	183	/* Do not need to verify session setups with signature "BSRSPYL " */
50c2f753	184	if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
b6b38f70 JP	185	cFYI(1, "dummy signature received for smb command 0x%x",
b6b38f70 JP	186	cifs_pdu->Command);
1da177e4 LT	187
	188	/* save off the origiginal signature so we can modify the smb and check
	189	its signature against what the server sent */
50c2f753	190	memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
1da177e4	191
50c2f753 SF	192	cifs_pdu->Signature.Sequence.SequenceNumber =
50c2f753 SF	193	cpu_to_le32(expected_sequence_number);
1da177e4 LT	194	cifs_pdu->Signature.Sequence.Reserved = 0;
1da177e4 LT	195
5f98ca9a	196	rc = cifs_calculate_signature(cifs_pdu, session_key,
1da177e4 LT	197	what_we_think_sig_should_be);
1da177e4 LT	198
50c2f753	199	if (rc)
1da177e4 LT	200	return rc;
1da177e4 LT	201
50c2f753 SF	202	/* cifs_dump_mem("what we think it should be: ",
50c2f753 SF	203	what_we_think_sig_should_be, 16); */
1da177e4	204
50c2f753	205	if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
1da177e4 LT	206	return -EACCES;
	207	else
	208	return 0;
	209
	210	}
	211
	212	/* We fill in key by putting in 40 byte array which was allocated by caller */
5f98ca9a	213	int cifs_calculate_session_key(struct session_key key, const char rn,
b609f06a	214	const char *password)
1da177e4 LT	215	{
	216	char temp_key[16];
	217	if ((key == NULL) \|\| (rn == NULL))
	218	return -EINVAL;
	219
	220	E_md4hash(password, temp_key);
b609f06a SF	221	mdfour(key->data.ntlm, temp_key, 16);
	222	memcpy(key->data.ntlm+16, rn, CIFS_SESS_KEY_SIZE);
	223	key->len = 40;
1da177e4 LT	224	return 0;
	225	}
	226
7c7b25bc	227	#ifdef CONFIG_CIFS_WEAK_PW_HASH
4e53a3fb JL	228	void calc_lanman_hash(const char password, const char cryptkey, bool encrypt,
4e53a3fb JL	229	char *lnm_session_key)
7c7b25bc SF	230	{
	231	int i;
	232	char password_with_pad[CIFS_ENCPWD_SIZE];
	233
	234	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
4e53a3fb JL	235	if (password)
	236	strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
	237
04912d6a	238	if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
4e53a3fb JL	239	memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE);
	240	memcpy(lnm_session_key, password_with_pad,
	241	CIFS_ENCPWD_SIZE);
	242	return;
	243	}
bdc4bf6e	244
7c7b25bc SF	245	/* calculate old style session key */
	246	/* calling toupper is less broken than repeatedly
	247	calling nls_toupper would be since that will never
	248	work for UTF8, but neither handles multibyte code pages
	249	but the only alternative would be converting to UCS-16 (Unicode)
	250	(using a routine something like UniStrupr) then
	251	uppercasing and then converting back from Unicode - which
	252	would only worth doing it if we knew it were utf8. Basically
	253	utf8 and other multibyte codepages each need their own strupper
	254	function since a byte at a time will ont work. */
	255
ef571cad	256	for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
7c7b25bc	257	password_with_pad[i] = toupper(password_with_pad[i]);
7c7b25bc	258
4e53a3fb JL	259	SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
4e53a3fb JL	260
7c7b25bc SF	261	/* clear password before we return/free memory */
	262	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
	263	}
	264	#endif /* CIFS_WEAK_PW_HASH */
	265
9daa42e2 SP	266	/* Build a proper attribute value/target info pairs blob.
	267	* Fill in netbios and dns domain name and workstation name
	268	* and client time (total five av pairs and + one end of fields indicator.
	269	* Allocate domain name which gets freed when session struct is deallocated.
2b149f11 SP	270	*/
2b149f11 SP	271	static int
9daa42e2	272	build_avpair_blob(struct cifsSesInfo ses, const struct nls_table nls_cp)
2b149f11	273	{
9daa42e2 SP	274	unsigned int dlen;
	275	unsigned int wlen;
	276	unsigned int size = 6 * sizeof(struct ntlmssp2_name);
	277	__le64 curtime;
	278	char *defdmname = "WORKGROUP";
	279	unsigned char *blobptr;
2b149f11 SP	280	struct ntlmssp2_name *attrptr;
2b149f11 SP	281
9daa42e2 SP	282	if (!ses->domainName) {
	283	ses->domainName = kstrdup(defdmname, GFP_KERNEL);
	284	if (!ses->domainName)
	285	return -ENOMEM;
	286	}
	287
	288	dlen = strlen(ses->domainName);
	289	wlen = strlen(ses->server->hostname);
	290
	291	/* The length of this blob is a size which is
	292	* six times the size of a structure which holds name/size +
	293	* two times the unicode length of a domain name +
	294	* two times the unicode length of a server name +
	295	* size of a timestamp (which is 8 bytes).
	296	*/
	297	ses->tilen = size + 2 * (2 * dlen) + 2 * (2 * wlen) + 8;
2b149f11 SP	298	ses->tiblob = kzalloc(ses->tilen, GFP_KERNEL);
	299	if (!ses->tiblob) {
	300	ses->tilen = 0;
	301	cERROR(1, "Challenge target info allocation failure");
	302	return -ENOMEM;
	303	}
9daa42e2 SP	304
	305	blobptr = ses->tiblob;
	306	attrptr = (struct ntlmssp2_name *) blobptr;
	307
	308	attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
	309	attrptr->length = cpu_to_le16(2 * dlen);
	310	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	311	cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
	312
	313	blobptr += 2 * dlen;
	314	attrptr = (struct ntlmssp2_name *) blobptr;
	315
	316	attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_COMPUTER_NAME);
	317	attrptr->length = cpu_to_le16(2 * wlen);
	318	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	319	cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);
	320
	321	blobptr += 2 * wlen;
	322	attrptr = (struct ntlmssp2_name *) blobptr;
	323
	324	attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_DOMAIN_NAME);
	325	attrptr->length = cpu_to_le16(2 * dlen);
	326	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	327	cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
	328
	329	blobptr += 2 * dlen;
	330	attrptr = (struct ntlmssp2_name *) blobptr;
	331
	332	attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_COMPUTER_NAME);
	333	attrptr->length = cpu_to_le16(2 * wlen);
	334	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	335	cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);
	336
	337	blobptr += 2 * wlen;
	338	attrptr = (struct ntlmssp2_name *) blobptr;
	339
	340	attrptr->type = cpu_to_le16(NTLMSSP_AV_TIMESTAMP);
	341	attrptr->length = cpu_to_le16(sizeof(__le64));
	342	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
	343	curtime = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
	344	memcpy(blobptr, &curtime, sizeof(__le64));
2b149f11 SP	345
	346	return 0;
	347	}
	348
	349	/* Server has provided av pairs/target info in the type 2 challenge
	350	* packet and we have plucked it and stored within smb session.
	351	* We parse that blob here to find netbios domain name to be used
	352	* as part of ntlmv2 authentication (in Target String), if not already
	353	* specified on the command line.
	354	* If this function returns without any error but without fetching
	355	* domain name, authentication may fail against some server but
	356	* may not fail against other (those who are not very particular
	357	* about target string i.e. for some, just user name might suffice.
	358	*/
	359	static int
	360	find_domain_name(struct cifsSesInfo *ses)
	361	{
	362	unsigned int attrsize;
	363	unsigned int type;
	364	unsigned int onesize = sizeof(struct ntlmssp2_name);
	365	unsigned char *blobptr;
	366	unsigned char *blobend;
	367	struct ntlmssp2_name *attrptr;
	368
	369	if (!ses->tilen \|\| !ses->tiblob)
	370	return 0;
	371
	372	blobptr = ses->tiblob;
	373	blobend = ses->tiblob + ses->tilen;
	374
	375	while (blobptr + onesize < blobend) {
	376	attrptr = (struct ntlmssp2_name *) blobptr;
	377	type = le16_to_cpu(attrptr->type);
	378	if (type == NTLMSSP_AV_EOL)
	379	break;
	380	blobptr += 2; /* advance attr type */
	381	attrsize = le16_to_cpu(attrptr->length);
	382	blobptr += 2; /* advance attr size */
	383	if (blobptr + attrsize > blobend)
	384	break;
	385	if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
	386	if (!attrsize)
	387	break;
	388	if (!ses->domainName) {
ccc46a74	389	struct nls_table *default_nls;
2b149f11 SP	390	ses->domainName =
	391	kmalloc(attrsize + 1, GFP_KERNEL);
	392	if (!ses->domainName)
	393	return -ENOMEM;
ccc46a74	394	default_nls = load_nls_default();
2b149f11 SP	395	cifs_from_ucs2(ses->domainName,
2b149f11 SP	396	(__le16 *)blobptr, attrsize, attrsize,
ccc46a74 JL	397	default_nls, false);
ccc46a74 JL	398	unload_nls(default_nls);
2b149f11 SP	399	break;
	400	}
	401	}
	402	blobptr += attrsize; /* advance attr value */
	403	}
	404
	405	return 0;
	406	}
	407
50c2f753 SF	408	static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
50c2f753 SF	409	const struct nls_table *nls_cp)
a8ee0344 SF	410	{
	411	int rc = 0;
	412	int len;
c8e56f1f SF	413	char nt_hash[16];
c8e56f1f SF	414	struct HMACMD5Context *pctxt;
50c2f753 SF	415	wchar_t *user;
50c2f753 SF	416	wchar_t *domain;
a8ee0344	417
c8e56f1f	418	pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);
a8ee0344	419
c8e56f1f SF	420	if (pctxt == NULL)
c8e56f1f SF	421	return -ENOMEM;
56234e27	422
c8e56f1f SF	423	/* calculate md4 hash of password */
c8e56f1f SF	424	E_md4hash(ses->password, nt_hash);
9fbc5908	425
c8e56f1f SF	426	/* convert Domainname to unicode and uppercase */
c8e56f1f SF	427	hmac_md5_init_limK_to_64(nt_hash, 16, pctxt);
a8ee0344 SF	428
a8ee0344 SF	429	/* convert ses->userName to unicode and uppercase */
1717ffc5 SF	430	len = strlen(ses->userName);
1717ffc5 SF	431	user = kmalloc(2 + (len * 2), GFP_KERNEL);
56234e27	432	if (user == NULL)
1717ffc5	433	goto calc_exit_2;
8f2376ad	434	len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp);
1717ffc5	435	UniStrupr(user);
c8e56f1f	436	hmac_md5_update((char )user, 2len, pctxt);
a8ee0344 SF	437
a8ee0344 SF	438	/* convert ses->domainName to unicode and uppercase */
50c2f753	439	if (ses->domainName) {
1717ffc5	440	len = strlen(ses->domainName);
a8ee0344	441
50c2f753	442	domain = kmalloc(2 + (len * 2), GFP_KERNEL);
56234e27	443	if (domain == NULL)
1717ffc5	444	goto calc_exit_1;
8f2376ad CG	445	len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
8f2376ad CG	446	nls_cp);
b609f06a SF	447	/* the following line was removed since it didn't work well
	448	with lower cased domain name that passed as an option.
	449	Maybe converting the domain name earlier makes sense */
	450	/* UniStrupr(domain); */
a8ee0344	451
c8e56f1f	452	hmac_md5_update((char )domain, 2len, pctxt);
50c2f753	453
1717ffc5 SF	454	kfree(domain);
	455	}
	456	calc_exit_1:
	457	kfree(user);
	458	calc_exit_2:
50c2f753	459	/* BB FIXME what about bytes 24 through 40 of the signing key?
1717ffc5	460	compare with the NTLM example */
c8e56f1f	461	hmac_md5_final(ses->server->ntlmv2_hash, pctxt);
9fbc5908	462
c8e56f1f	463	kfree(pctxt);
9fbc5908 SF	464	return rc;
	465	}
	466
2b149f11 SP	467	int
2b149f11 SP	468	setup_ntlmv2_rsp(struct cifsSesInfo ses, char resp_buf,
9fbc5908 SF	469	const struct nls_table *nls_cp)
9fbc5908 SF	470	{
c8e56f1f	471	int rc;
50c2f753	472	struct ntlmv2_resp buf = (struct ntlmv2_resp )resp_buf;
c8e56f1f	473	struct HMACMD5Context context;
6d027cfd SF	474
	475	buf->blob_signature = cpu_to_le32(0x00000101);
	476	buf->reserved = 0;
	477	buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
1717ffc5	478	get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
6d027cfd	479	buf->reserved2 = 0;
2b149f11 SP	480
	481	if (ses->server->secType == RawNTLMSSP) {
	482	if (!ses->domainName) {
	483	rc = find_domain_name(ses);
	484	if (rc) {
	485	cERROR(1, "error %d finding domain name", rc);
	486	goto setup_ntlmv2_rsp_ret;
	487	}
	488	}
	489	} else {
9daa42e2	490	rc = build_avpair_blob(ses, nls_cp);
2b149f11 SP	491	if (rc) {
	492	cERROR(1, "error %d building av pair blob", rc);
	493	return rc;
	494	}
	495	}
a8ee0344	496
6d027cfd	497	/* calculate buf->ntlmv2_hash */
1717ffc5	498	rc = calc_ntlmv2_hash(ses, nls_cp);
2b149f11	499	if (rc) {
b6b38f70	500	cERROR(1, "could not get v2 hash rc %d", rc);
2b149f11 SP	501	goto setup_ntlmv2_rsp_ret;
2b149f11 SP	502	}
c8e56f1f	503	CalcNTLMv2_response(ses, resp_buf);
b609f06a	504
c8e56f1f SF	505	/* now calculate the MAC key for NTLMv2 */
	506	hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
	507	hmac_md5_update(resp_buf, 16, &context);
5f98ca9a	508	hmac_md5_final(ses->server->session_key.data.ntlmv2.key, &context);
b609f06a	509
5f98ca9a	510	memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
c8e56f1f	511	sizeof(struct ntlmv2_resp));
5f98ca9a	512	ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);
2b149f11 SP	513
	514	return 0;
	515
	516	setup_ntlmv2_rsp_ret:
	517	kfree(ses->tiblob);
	518	ses->tiblob = NULL;
	519	ses->tilen = 0;
	520
	521	return rc;
6d027cfd SF	522	}
6d027cfd SF	523
c8e56f1f SF	524	void CalcNTLMv2_response(const struct cifsSesInfo *ses,
c8e56f1f SF	525	char *v2_session_response)
9fbc5908	526	{
c8e56f1f SF	527	struct HMACMD5Context context;
	528	/* rest of v2 struct already generated */
	529	memcpy(v2_session_response + 8, ses->server->cryptKey, 8);
	530	hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
9fbc5908	531
c8e56f1f SF	532	hmac_md5_update(v2_session_response+8,
c8e56f1f SF	533	sizeof(struct ntlmv2_resp) - 8, &context);
2d20ca83	534
2b149f11 SP	535	if (ses->tilen)
	536	hmac_md5_update(ses->tiblob, ses->tilen, &context);
	537
c8e56f1f SF	538	hmac_md5_final(v2_session_response, &context);
c8e56f1f SF	539	/* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
1da177e4	540	}