[mirror_ubuntu-artful-kernel.git] / fs / cifs / smb2transport.c

/*
 *   fs/cifs/smb2transport.c
 *
 *   Copyright (C) International Business Machines  Corp., 2002, 2011
 *                 Etersoft, 2012
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *              Jeremy Allison (jra@samba.org) 2006
 *              Pavel Shilovsky (pshilovsky@samba.org) 2012
 *
 *   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/list.h>
#include <linux/wait.h>
#include <linux/net.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <asm/processor.h>
#include <linux/mempool.h>
#include <linux/highmem.h>
#include "smb2pdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_debug.h"
#include "smb2status.h"
#include "smb2glob.h"

static int
smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
{
	int rc;
	unsigned int size;

	if (server->secmech.sdeschmacsha256 != NULL)
		return 0; /* already allocated */

	server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0);
	if (IS_ERR(server->secmech.hmacsha256)) {
		cifs_dbg(VFS, "could not allocate crypto hmacsha256\n");
		rc = PTR_ERR(server->secmech.hmacsha256);
		server->secmech.hmacsha256 = NULL;
		return rc;
	}

	size = sizeof(struct shash_desc) +
			crypto_shash_descsize(server->secmech.hmacsha256);
	server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL);
	if (!server->secmech.sdeschmacsha256) {
		crypto_free_shash(server->secmech.hmacsha256);
		server->secmech.hmacsha256 = NULL;
		return -ENOMEM;
	}
	server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256;
	server->secmech.sdeschmacsha256->shash.flags = 0x0;

	return 0;
}

static int
smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
{
	unsigned int size;
	int rc;

	if (server->secmech.sdesccmacaes != NULL)
		return 0;  /* already allocated */

	rc = smb2_crypto_shash_allocate(server);
	if (rc)
		return rc;

	server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0);
	if (IS_ERR(server->secmech.cmacaes)) {
		cifs_dbg(VFS, "could not allocate crypto cmac-aes");
		kfree(server->secmech.sdeschmacsha256);
		server->secmech.sdeschmacsha256 = NULL;
		crypto_free_shash(server->secmech.hmacsha256);
		server->secmech.hmacsha256 = NULL;
		rc = PTR_ERR(server->secmech.cmacaes);
		server->secmech.cmacaes = NULL;
		return rc;
	}

	size = sizeof(struct shash_desc) +
			crypto_shash_descsize(server->secmech.cmacaes);
	server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL);
	if (!server->secmech.sdesccmacaes) {
		cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__);
		kfree(server->secmech.sdeschmacsha256);
		server->secmech.sdeschmacsha256 = NULL;
		crypto_free_shash(server->secmech.hmacsha256);
		crypto_free_shash(server->secmech.cmacaes);
		server->secmech.hmacsha256 = NULL;
		server->secmech.cmacaes = NULL;
		return -ENOMEM;
	}
	server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes;
	server->secmech.sdesccmacaes->shash.flags = 0x0;

	return 0;
}


int
smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	int i, rc;
	unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
	unsigned char *sigptr = smb2_signature;
	struct kvec *iov = rqst->rq_iov;
	int n_vec = rqst->rq_nvec;
	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base;

	memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);

	rc = smb2_crypto_shash_allocate(server);
	if (rc) {
		cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__);
		return rc;
	}

	rc = crypto_shash_setkey(server->secmech.hmacsha256,
		server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
		return rc;
	}

	rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not init sha256", __func__);
		return rc;
	}

	for (i = 0; i < n_vec; i++) {
		if (iov[i].iov_len == 0)
			continue;
		if (iov[i].iov_base == NULL) {
			cifs_dbg(VFS, "null iovec entry\n");
			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.sdeschmacsha256->shash,
				iov[i].iov_base + 4, iov[i].iov_len - 4);
		} else {
			rc =
			crypto_shash_update(
				&server->secmech.sdeschmacsha256->shash,
				iov[i].iov_base, iov[i].iov_len);
		}
		if (rc) {
			cifs_dbg(VFS, "%s: Could not update with payload\n",
				 __func__);
			return rc;
		}
	}

	/* now hash over the rq_pages array */
	for (i = 0; i < rqst->rq_npages; i++) {
		struct kvec p_iov;

		cifs_rqst_page_to_kvec(rqst, i, &p_iov);
		crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
					p_iov.iov_base, p_iov.iov_len);
		kunmap(rqst->rq_pages[i]);
	}

	rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
				sigptr);
	if (rc)
		cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);

	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);

	return rc;
}

void
generate_smb3signingkey(struct TCP_Server_Info *server)
{
	unsigned char zero = 0x0;
	__u8 i[4] = {0, 0, 0, 1};
	__u8 L[4] = {0, 0, 0, 128};
	int rc = 0;
	unsigned char prfhash[SMB2_HMACSHA256_SIZE];
	unsigned char *hashptr = prfhash;

	memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
	memset(server->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE);

	rc = smb3_crypto_shash_allocate(server);
	if (rc) {
		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_setkey(server->secmech.hmacsha256,
		server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not set with session key\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
				i, 4);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with n\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
				"SMB2AESCMAC", 12);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with label\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
				&zero, 1);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with zero\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
				"SmbSign", 8);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with context\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
				L, 4);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not update with L\n", __func__);
		goto smb3signkey_ret;
	}

	rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
				hashptr);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
		goto smb3signkey_ret;
	}

	memcpy(server->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE);

smb3signkey_ret:
	return;
}

int
smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	int i, rc;
	unsigned char smb3_signature[SMB2_CMACAES_SIZE];
	unsigned char *sigptr = smb3_signature;
	struct kvec *iov = rqst->rq_iov;
	int n_vec = rqst->rq_nvec;
	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base;

	memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);

	rc = crypto_shash_setkey(server->secmech.cmacaes,
		server->smb3signingkey, SMB2_CMACAES_SIZE);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
		return rc;
	}

	/*
	 * we already allocate sdesccmacaes when we init smb3 signing key,
	 * so unlike smb2 case we do not have to check here if secmech are
	 * initialized
	 */
	rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash);
	if (rc) {
		cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
		return rc;
	}

	for (i = 0; i < n_vec; i++) {
		if (iov[i].iov_len == 0)
			continue;
		if (iov[i].iov_base == NULL) {
			cifs_dbg(VFS, "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.sdesccmacaes->shash,
				iov[i].iov_base + 4, iov[i].iov_len - 4);
		} else {
			rc =
			crypto_shash_update(
				&server->secmech.sdesccmacaes->shash,
				iov[i].iov_base, iov[i].iov_len);
		}
		if (rc) {
			cifs_dbg(VFS, "%s: Couldn't update cmac aes with payload\n",
							__func__);
			return rc;
		}
	}

	/* now hash over the rq_pages array */
	for (i = 0; i < rqst->rq_npages; i++) {
		struct kvec p_iov;

		cifs_rqst_page_to_kvec(rqst, i, &p_iov);
		crypto_shash_update(&server->secmech.sdesccmacaes->shash,
					p_iov.iov_base, p_iov.iov_len);
		kunmap(rqst->rq_pages[i]);
	}

	rc = crypto_shash_final(&server->secmech.sdesccmacaes->shash,
						sigptr);
	if (rc)
		cifs_dbg(VFS, "%s: Could not generate cmac aes\n", __func__);

	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);

	return rc;
}

/* must be called with server->srv_mutex held */
static int
smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	int rc = 0;
	struct smb2_hdr *smb2_pdu = rqst->rq_iov[0].iov_base;

	if (!(smb2_pdu->Flags & SMB2_FLAGS_SIGNED) ||
	    server->tcpStatus == CifsNeedNegotiate)
		return rc;

	if (!server->session_estab) {
		strncpy(smb2_pdu->Signature, "BSRSPYL", 8);
		return rc;
	}

	rc = server->ops->calc_signature(rqst, server);

	return rc;
}

int
smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
	unsigned int rc;
	char server_response_sig[16];
	struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;

	if ((smb2_pdu->Command == SMB2_NEGOTIATE) ||
	    (smb2_pdu->Command == SMB2_OPLOCK_BREAK) ||
	    (!server->session_estab))
		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(smb2_pdu->Signature, "BSRSPYL ", 8) == 0)
		cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
			 smb2_pdu->Command);

	/*
	 * Save off the origiginal signature so we can modify the smb and check
	 * our calculated signature against what the server sent.
	 */
	memcpy(server_response_sig, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE);

	memset(smb2_pdu->Signature, 0, SMB2_SIGNATURE_SIZE);

	mutex_lock(&server->srv_mutex);
	rc = server->ops->calc_signature(rqst, server);
	mutex_unlock(&server->srv_mutex);

	if (rc)
		return rc;

	if (memcmp(server_response_sig, smb2_pdu->Signature,
		   SMB2_SIGNATURE_SIZE))
		return -EACCES;
	else
		return 0;
}

/*
 * Set message id for the request. Should be called after wait_for_free_request
 * and when srv_mutex is held.
 */
static inline void
smb2_seq_num_into_buf(struct TCP_Server_Info *server, struct smb2_hdr *hdr)
{
	hdr->MessageId = get_next_mid(server);
}

static struct mid_q_entry *
smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer,
		     struct TCP_Server_Info *server)
{
	struct mid_q_entry *temp;

	if (server == NULL) {
		cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
		return NULL;
	}

	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
	if (temp == NULL)
		return temp;
	else {
		memset(temp, 0, sizeof(struct mid_q_entry));
		temp->mid = smb_buffer->MessageId;	/* always LE */
		temp->pid = current->pid;
		temp->command = smb_buffer->Command;	/* Always LE */
		temp->when_alloc = jiffies;
		temp->server = server;

		/*
		 * The default is for the mid to be synchronous, so the
		 * default callback just wakes up the current task.
		 */
		temp->callback = cifs_wake_up_task;
		temp->callback_data = current;
	}

	atomic_inc(&midCount);
	temp->mid_state = MID_REQUEST_ALLOCATED;
	return temp;
}

static int
smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_hdr *buf,
		   struct mid_q_entry **mid)
{
	if (ses->server->tcpStatus == CifsExiting)
		return -ENOENT;

	if (ses->server->tcpStatus == CifsNeedReconnect) {
		cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
		return -EAGAIN;
	}

	if (ses->status != CifsGood) {
		/* check if SMB2 session is bad because we are setting it up */
		if ((buf->Command != SMB2_SESSION_SETUP) &&
		    (buf->Command != SMB2_NEGOTIATE))
			return -EAGAIN;
		/* else ok - we are setting up session */
	}
	*mid = smb2_mid_entry_alloc(buf, ses->server);
	if (*mid == NULL)
		return -ENOMEM;
	spin_lock(&GlobalMid_Lock);
	list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
	spin_unlock(&GlobalMid_Lock);
	return 0;
}

int
smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
		   bool log_error)
{
	unsigned int len = get_rfc1002_length(mid->resp_buf);
	struct kvec iov;
	struct smb_rqst rqst = { .rq_iov = &iov,
				 .rq_nvec = 1 };

	iov.iov_base = (char *)mid->resp_buf;
	iov.iov_len = get_rfc1002_length(mid->resp_buf) + 4;

	dump_smb(mid->resp_buf, min_t(u32, 80, len));
	/* convert the length into a more usable form */
	if (len > 24 && server->sign) {
		int rc;

		rc = smb2_verify_signature(&rqst, server);
		if (rc)
			cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
				 rc);
	}

	return map_smb2_to_linux_error(mid->resp_buf, log_error);
}

struct mid_q_entry *
smb2_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
{
	int rc;
	struct smb2_hdr *hdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;
	struct mid_q_entry *mid;

	smb2_seq_num_into_buf(ses->server, hdr);

	rc = smb2_get_mid_entry(ses, hdr, &mid);
	if (rc)
		return ERR_PTR(rc);
	rc = smb2_sign_rqst(rqst, ses->server);
	if (rc) {
		cifs_delete_mid(mid);
		return ERR_PTR(rc);
	}
	return mid;
}

struct mid_q_entry *
smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
{
	int rc;
	struct smb2_hdr *hdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;
	struct mid_q_entry *mid;

	smb2_seq_num_into_buf(server, hdr);

	mid = smb2_mid_entry_alloc(hdr, server);
	if (mid == NULL)
		return ERR_PTR(-ENOMEM);

	rc = smb2_sign_rqst(rqst, server);
	if (rc) {
		DeleteMidQEntry(mid);
		return ERR_PTR(rc);
	}

	return mid;
}
Commit	Line	Data
2dc7e1c0 PS	1	/*
	2	* fs/cifs/smb2transport.c
	3	*
	4	* Copyright (C) International Business Machines Corp., 2002, 2011
	5	* Etersoft, 2012
	6	* Author(s): Steve French (sfrench@us.ibm.com)
	7	* Jeremy Allison (jra@samba.org) 2006
	8	* Pavel Shilovsky (pshilovsky@samba.org) 2012
	9	*
	10	* This library is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU Lesser General Public License as published
	12	* by the Free Software Foundation; either version 2.1 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This library is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	18	* the GNU Lesser General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU Lesser General Public License
	21	* along with this library; if not, write to the Free Software
	22	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	23	*/
	24
	25	#include <linux/fs.h>
	26	#include <linux/list.h>
	27	#include <linux/wait.h>
	28	#include <linux/net.h>
	29	#include <linux/delay.h>
	30	#include <linux/uaccess.h>
	31	#include <asm/processor.h>
	32	#include <linux/mempool.h>
fb308a6f	33	#include <linux/highmem.h>
2dc7e1c0 PS	34	#include "smb2pdu.h"
	35	#include "cifsglob.h"
	36	#include "cifsproto.h"
	37	#include "smb2proto.h"
	38	#include "cifs_debug.h"
	39	#include "smb2status.h"
3c1bf7e4 PS	40	#include "smb2glob.h"
3c1bf7e4 PS	41
95dc8dd1 SF	42	static int
	43	smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
	44	{
ba482029	45	int rc;
95dc8dd1 SF	46	unsigned int size;
	47
	48	if (server->secmech.sdeschmacsha256 != NULL)
	49	return 0; /* already allocated */
	50
	51	server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0);
	52	if (IS_ERR(server->secmech.hmacsha256)) {
	53	cifs_dbg(VFS, "could not allocate crypto hmacsha256\n");
ba482029 JL	54	rc = PTR_ERR(server->secmech.hmacsha256);
	55	server->secmech.hmacsha256 = NULL;
	56	return rc;
95dc8dd1 SF	57	}
	58
	59	size = sizeof(struct shash_desc) +
	60	crypto_shash_descsize(server->secmech.hmacsha256);
	61	server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL);
	62	if (!server->secmech.sdeschmacsha256) {
	63	crypto_free_shash(server->secmech.hmacsha256);
	64	server->secmech.hmacsha256 = NULL;
	65	return -ENOMEM;
	66	}
	67	server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256;
	68	server->secmech.sdeschmacsha256->shash.flags = 0x0;
	69
	70	return 0;
	71	}
	72
	73	static int
	74	smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
	75	{
	76	unsigned int size;
	77	int rc;
	78
	79	if (server->secmech.sdesccmacaes != NULL)
	80	return 0; /* already allocated */
	81
	82	rc = smb2_crypto_shash_allocate(server);
	83	if (rc)
	84	return rc;
	85
	86	server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0);
	87	if (IS_ERR(server->secmech.cmacaes)) {
	88	cifs_dbg(VFS, "could not allocate crypto cmac-aes");
	89	kfree(server->secmech.sdeschmacsha256);
	90	server->secmech.sdeschmacsha256 = NULL;
	91	crypto_free_shash(server->secmech.hmacsha256);
	92	server->secmech.hmacsha256 = NULL;
ba482029 JL	93	rc = PTR_ERR(server->secmech.cmacaes);
	94	server->secmech.cmacaes = NULL;
	95	return rc;
95dc8dd1 SF	96	}
	97
	98	size = sizeof(struct shash_desc) +
	99	crypto_shash_descsize(server->secmech.cmacaes);
	100	server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL);
	101	if (!server->secmech.sdesccmacaes) {
	102	cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__);
	103	kfree(server->secmech.sdeschmacsha256);
	104	server->secmech.sdeschmacsha256 = NULL;
	105	crypto_free_shash(server->secmech.hmacsha256);
	106	crypto_free_shash(server->secmech.cmacaes);
	107	server->secmech.hmacsha256 = NULL;
	108	server->secmech.cmacaes = NULL;
	109	return -ENOMEM;
	110	}
	111	server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes;
	112	server->secmech.sdesccmacaes->shash.flags = 0x0;
	113
	114	return 0;
	115	}
	116
	117
38107d45	118	int
0b688cfc	119	smb2_calc_signature(struct smb_rqst rqst, struct TCP_Server_Info server)
3c1bf7e4 PS	120	{
	121	int i, rc;
	122	unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
	123	unsigned char *sigptr = smb2_signature;
0b688cfc JL	124	struct kvec *iov = rqst->rq_iov;
0b688cfc JL	125	int n_vec = rqst->rq_nvec;
3c1bf7e4 PS	126	struct smb2_hdr smb2_pdu = (struct smb2_hdr )iov[0].iov_base;
	127
	128	memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
	129	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);
	130
95dc8dd1 SF	131	rc = smb2_crypto_shash_allocate(server);
	132	if (rc) {
	133	cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__);
	134	return rc;
	135	}
	136
3c1bf7e4 PS	137	rc = crypto_shash_setkey(server->secmech.hmacsha256,
	138	server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
	139	if (rc) {
f96637be	140	cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
3c1bf7e4 PS	141	return rc;
	142	}
	143
	144	rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
	145	if (rc) {
95dc8dd1	146	cifs_dbg(VFS, "%s: Could not init sha256", __func__);
3c1bf7e4 PS	147	return rc;
	148	}
	149
	150	for (i = 0; i < n_vec; i++) {
	151	if (iov[i].iov_len == 0)
	152	continue;
	153	if (iov[i].iov_base == NULL) {
f96637be	154	cifs_dbg(VFS, "null iovec entry\n");
3c1bf7e4 PS	155	return -EIO;
	156	}
	157	/*
	158	* The first entry includes a length field (which does not get
	159	* signed that occupies the first 4 bytes before the header).
	160	*/
	161	if (i == 0) {
	162	if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
	163	break; /* nothing to sign or corrupt header */
	164	rc =
	165	crypto_shash_update(
	166	&server->secmech.sdeschmacsha256->shash,
	167	iov[i].iov_base + 4, iov[i].iov_len - 4);
	168	} else {
	169	rc =
	170	crypto_shash_update(
	171	&server->secmech.sdeschmacsha256->shash,
	172	iov[i].iov_base, iov[i].iov_len);
	173	}
	174	if (rc) {
f96637be JP	175	cifs_dbg(VFS, "%s: Could not update with payload\n",
f96637be JP	176	__func__);
3c1bf7e4 PS	177	return rc;
	178	}
	179	}
	180
fb308a6f JL	181	/* now hash over the rq_pages array */
	182	for (i = 0; i < rqst->rq_npages; i++) {
	183	struct kvec p_iov;
	184
	185	cifs_rqst_page_to_kvec(rqst, i, &p_iov);
	186	crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	187	p_iov.iov_base, p_iov.iov_len);
	188	kunmap(rqst->rq_pages[i]);
	189	}
	190
3c1bf7e4 PS	191	rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
	192	sigptr);
	193	if (rc)
f96637be	194	cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
3c1bf7e4 PS	195
	196	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);
	197
	198	return rc;
	199	}
	200
e65a5cb4	201	void
429b46f4 SF	202	generate_smb3signingkey(struct TCP_Server_Info *server)
	203	{
	204	unsigned char zero = 0x0;
	205	__u8 i[4] = {0, 0, 0, 1};
	206	__u8 L[4] = {0, 0, 0, 128};
	207	int rc = 0;
	208	unsigned char prfhash[SMB2_HMACSHA256_SIZE];
	209	unsigned char *hashptr = prfhash;
	210
	211	memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
	212	memset(server->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE);
	213
95dc8dd1 SF	214	rc = smb3_crypto_shash_allocate(server);
	215	if (rc) {
	216	cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
	217	goto smb3signkey_ret;
	218	}
	219
429b46f4 SF	220	rc = crypto_shash_setkey(server->secmech.hmacsha256,
	221	server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
	222	if (rc) {
	223	cifs_dbg(VFS, "%s: Could not set with session key\n", __func__);
	224	goto smb3signkey_ret;
	225	}
	226
	227	rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
	228	if (rc) {
	229	cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
	230	goto smb3signkey_ret;
	231	}
	232
	233	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	234	i, 4);
	235	if (rc) {
	236	cifs_dbg(VFS, "%s: Could not update with n\n", __func__);
	237	goto smb3signkey_ret;
	238	}
	239
	240	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	241	"SMB2AESCMAC", 12);
	242	if (rc) {
	243	cifs_dbg(VFS, "%s: Could not update with label\n", __func__);
	244	goto smb3signkey_ret;
	245	}
	246
	247	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	248	&zero, 1);
	249	if (rc) {
	250	cifs_dbg(VFS, "%s: Could not update with zero\n", __func__);
	251	goto smb3signkey_ret;
	252	}
	253
	254	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	255	"SmbSign", 8);
	256	if (rc) {
	257	cifs_dbg(VFS, "%s: Could not update with context\n", __func__);
	258	goto smb3signkey_ret;
	259	}
	260
	261	rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
	262	L, 4);
	263	if (rc) {
	264	cifs_dbg(VFS, "%s: Could not update with L\n", __func__);
	265	goto smb3signkey_ret;
	266	}
	267
	268	rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
	269	hashptr);
	270	if (rc) {
	271	cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
	272	goto smb3signkey_ret;
	273	}
	274
	275	memcpy(server->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE);
	276
	277	smb3signkey_ret:
e65a5cb4	278	return;
429b46f4 SF	279	}
429b46f4 SF	280
38107d45 SF	281	int
	282	smb3_calc_signature(struct smb_rqst rqst, struct TCP_Server_Info server)
	283	{
429b46f4 SF	284	int i, rc;
	285	unsigned char smb3_signature[SMB2_CMACAES_SIZE];
	286	unsigned char *sigptr = smb3_signature;
	287	struct kvec *iov = rqst->rq_iov;
	288	int n_vec = rqst->rq_nvec;
	289	struct smb2_hdr smb2_pdu = (struct smb2_hdr )iov[0].iov_base;
	290
	291	memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
	292	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);
	293
	294	rc = crypto_shash_setkey(server->secmech.cmacaes,
	295	server->smb3signingkey, SMB2_CMACAES_SIZE);
	296	if (rc) {
	297	cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
	298	return rc;
	299	}
	300
95dc8dd1 SF	301	/*
	302	* we already allocate sdesccmacaes when we init smb3 signing key,
	303	* so unlike smb2 case we do not have to check here if secmech are
	304	* initialized
	305	*/
429b46f4 SF	306	rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash);
	307	if (rc) {
	308	cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
	309	return rc;
	310	}
	311
	312	for (i = 0; i < n_vec; i++) {
	313	if (iov[i].iov_len == 0)
	314	continue;
	315	if (iov[i].iov_base == NULL) {
	316	cifs_dbg(VFS, "null iovec entry");
	317	return -EIO;
	318	}
	319	/*
	320	* The first entry includes a length field (which does not get
	321	* signed that occupies the first 4 bytes before the header).
	322	*/
	323	if (i == 0) {
	324	if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
	325	break; /* nothing to sign or corrupt header */
	326	rc =
	327	crypto_shash_update(
	328	&server->secmech.sdesccmacaes->shash,
	329	iov[i].iov_base + 4, iov[i].iov_len - 4);
	330	} else {
	331	rc =
	332	crypto_shash_update(
	333	&server->secmech.sdesccmacaes->shash,
	334	iov[i].iov_base, iov[i].iov_len);
	335	}
	336	if (rc) {
	337	cifs_dbg(VFS, "%s: Couldn't update cmac aes with payload\n",
	338	__func__);
	339	return rc;
	340	}
	341	}
	342
	343	/* now hash over the rq_pages array */
	344	for (i = 0; i < rqst->rq_npages; i++) {
	345	struct kvec p_iov;
	346
	347	cifs_rqst_page_to_kvec(rqst, i, &p_iov);
	348	crypto_shash_update(&server->secmech.sdesccmacaes->shash,
	349	p_iov.iov_base, p_iov.iov_len);
	350	kunmap(rqst->rq_pages[i]);
	351	}
	352
	353	rc = crypto_shash_final(&server->secmech.sdesccmacaes->shash,
	354	sigptr);
	355	if (rc)
	356	cifs_dbg(VFS, "%s: Could not generate cmac aes\n", __func__);
	357
	358	memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE);
	359
	360	return rc;
38107d45 SF	361	}
38107d45 SF	362
3c1bf7e4 PS	363	/* must be called with server->srv_mutex held */
3c1bf7e4 PS	364	static int
0b688cfc	365	smb2_sign_rqst(struct smb_rqst rqst, struct TCP_Server_Info server)
3c1bf7e4 PS	366	{
3c1bf7e4 PS	367	int rc = 0;
0b688cfc	368	struct smb2_hdr *smb2_pdu = rqst->rq_iov[0].iov_base;
3c1bf7e4 PS	369
	370	if (!(smb2_pdu->Flags & SMB2_FLAGS_SIGNED) \|\|
	371	server->tcpStatus == CifsNeedNegotiate)
	372	return rc;
	373
	374	if (!server->session_estab) {
	375	strncpy(smb2_pdu->Signature, "BSRSPYL", 8);
	376	return rc;
	377	}
	378
38107d45	379	rc = server->ops->calc_signature(rqst, server);
3c1bf7e4 PS	380
	381	return rc;
	382	}
	383
	384	int
0b688cfc	385	smb2_verify_signature(struct smb_rqst rqst, struct TCP_Server_Info server)
3c1bf7e4 PS	386	{
	387	unsigned int rc;
	388	char server_response_sig[16];
0b688cfc	389	struct smb2_hdr smb2_pdu = (struct smb2_hdr )rqst->rq_iov[0].iov_base;
3c1bf7e4 PS	390
	391	if ((smb2_pdu->Command == SMB2_NEGOTIATE) \|\|
	392	(smb2_pdu->Command == SMB2_OPLOCK_BREAK) \|\|
	393	(!server->session_estab))
	394	return 0;
	395
	396	/*
	397	* BB what if signatures are supposed to be on for session but
	398	* server does not send one? BB
	399	*/
	400
	401	/* Do not need to verify session setups with signature "BSRSPYL " */
	402	if (memcmp(smb2_pdu->Signature, "BSRSPYL ", 8) == 0)
f96637be JP	403	cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
f96637be JP	404	smb2_pdu->Command);
3c1bf7e4 PS	405
	406	/*
	407	* Save off the origiginal signature so we can modify the smb and check
	408	* our calculated signature against what the server sent.
	409	*/
	410	memcpy(server_response_sig, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE);
	411
	412	memset(smb2_pdu->Signature, 0, SMB2_SIGNATURE_SIZE);
	413
	414	mutex_lock(&server->srv_mutex);
38107d45	415	rc = server->ops->calc_signature(rqst, server);
3c1bf7e4 PS	416	mutex_unlock(&server->srv_mutex);
	417
	418	if (rc)
	419	return rc;
	420
	421	if (memcmp(server_response_sig, smb2_pdu->Signature,
	422	SMB2_SIGNATURE_SIZE))
	423	return -EACCES;
	424	else
	425	return 0;
	426	}
	427
2dc7e1c0 PS	428	/*
	429	* Set message id for the request. Should be called after wait_for_free_request
	430	* and when srv_mutex is held.
	431	*/
	432	static inline void
	433	smb2_seq_num_into_buf(struct TCP_Server_Info server, struct smb2_hdr hdr)
	434	{
	435	hdr->MessageId = get_next_mid(server);
	436	}
	437
	438	static struct mid_q_entry *
	439	smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer,
	440	struct TCP_Server_Info *server)
	441	{
	442	struct mid_q_entry *temp;
	443
	444	if (server == NULL) {
f96637be	445	cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
2dc7e1c0 PS	446	return NULL;
	447	}
	448
	449	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
	450	if (temp == NULL)
	451	return temp;
	452	else {
	453	memset(temp, 0, sizeof(struct mid_q_entry));
	454	temp->mid = smb_buffer->MessageId; /* always LE */
	455	temp->pid = current->pid;
	456	temp->command = smb_buffer->Command; /* Always LE */
	457	temp->when_alloc = jiffies;
	458	temp->server = server;
	459
	460	/*
	461	* The default is for the mid to be synchronous, so the
	462	* default callback just wakes up the current task.
	463	*/
	464	temp->callback = cifs_wake_up_task;
	465	temp->callback_data = current;
	466	}
	467
	468	atomic_inc(&midCount);
	469	temp->mid_state = MID_REQUEST_ALLOCATED;
	470	return temp;
	471	}
	472
	473	static int
	474	smb2_get_mid_entry(struct cifs_ses ses, struct smb2_hdr buf,
	475	struct mid_q_entry **mid)
	476	{
	477	if (ses->server->tcpStatus == CifsExiting)
	478	return -ENOENT;
	479
	480	if (ses->server->tcpStatus == CifsNeedReconnect) {
f96637be	481	cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
2dc7e1c0 PS	482	return -EAGAIN;
	483	}
	484
	485	if (ses->status != CifsGood) {
	486	/* check if SMB2 session is bad because we are setting it up */
	487	if ((buf->Command != SMB2_SESSION_SETUP) &&
	488	(buf->Command != SMB2_NEGOTIATE))
	489	return -EAGAIN;
	490	/* else ok - we are setting up session */
	491	}
	492	*mid = smb2_mid_entry_alloc(buf, ses->server);
	493	if (*mid == NULL)
	494	return -ENOMEM;
	495	spin_lock(&GlobalMid_Lock);
	496	list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
	497	spin_unlock(&GlobalMid_Lock);
	498	return 0;
	499	}
	500
	501	int
	502	smb2_check_receive(struct mid_q_entry mid, struct TCP_Server_Info server,
	503	bool log_error)
	504	{
	505	unsigned int len = get_rfc1002_length(mid->resp_buf);
0b688cfc JL	506	struct kvec iov;
	507	struct smb_rqst rqst = { .rq_iov = &iov,
	508	.rq_nvec = 1 };
	509
	510	iov.iov_base = (char *)mid->resp_buf;
	511	iov.iov_len = get_rfc1002_length(mid->resp_buf) + 4;
2dc7e1c0 PS	512
	513	dump_smb(mid->resp_buf, min_t(u32, 80, len));
	514	/* convert the length into a more usable form */
38d77c50	515	if (len > 24 && server->sign) {
3c1bf7e4 PS	516	int rc;
3c1bf7e4 PS	517
0b688cfc	518	rc = smb2_verify_signature(&rqst, server);
3c1bf7e4	519	if (rc)
f96637be JP	520	cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
f96637be JP	521	rc);
3c1bf7e4	522	}
2dc7e1c0 PS	523
	524	return map_smb2_to_linux_error(mid->resp_buf, log_error);
	525	}
	526
fec344e3 JL	527	struct mid_q_entry *
fec344e3 JL	528	smb2_setup_request(struct cifs_ses ses, struct smb_rqst rqst)
2dc7e1c0 PS	529	{
2dc7e1c0 PS	530	int rc;
fec344e3	531	struct smb2_hdr hdr = (struct smb2_hdr )rqst->rq_iov[0].iov_base;
2dc7e1c0 PS	532	struct mid_q_entry *mid;
	533
	534	smb2_seq_num_into_buf(ses->server, hdr);
	535
	536	rc = smb2_get_mid_entry(ses, hdr, &mid);
	537	if (rc)
fec344e3 JL	538	return ERR_PTR(rc);
	539	rc = smb2_sign_rqst(rqst, ses->server);
	540	if (rc) {
3c1bf7e4	541	cifs_delete_mid(mid);
fec344e3 JL	542	return ERR_PTR(rc);
	543	}
	544	return mid;
2dc7e1c0 PS	545	}
2dc7e1c0 PS	546
fec344e3 JL	547	struct mid_q_entry *
fec344e3 JL	548	smb2_setup_async_request(struct TCP_Server_Info server, struct smb_rqst rqst)
c95b8eed	549	{
fec344e3 JL	550	int rc;
fec344e3 JL	551	struct smb2_hdr hdr = (struct smb2_hdr )rqst->rq_iov[0].iov_base;
c95b8eed PS	552	struct mid_q_entry *mid;
	553
	554	smb2_seq_num_into_buf(server, hdr);
	555
	556	mid = smb2_mid_entry_alloc(hdr, server);
	557	if (mid == NULL)
fec344e3	558	return ERR_PTR(-ENOMEM);
c95b8eed	559
fec344e3	560	rc = smb2_sign_rqst(rqst, server);
c95b8eed PS	561	if (rc) {
c95b8eed PS	562	DeleteMidQEntry(mid);
fec344e3	563	return ERR_PTR(rc);
3c1bf7e4 PS	564	}
3c1bf7e4 PS	565
fec344e3	566	return mid;
c95b8eed	567	}