Initial import

1 files changed, 612 insertions, 0 deletions

diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
new file mode 100644
index 000000000..d4c5b6f10
--- /dev/null
+++ b/fs/cifs/smb2transport.c
@@ -0,0 +1,612 @@
+/*
+ *   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;
+}
+
+static struct cifs_ses *
+smb2_find_smb_ses(struct smb2_hdr *smb2hdr, struct TCP_Server_Info *server)
+{
+	struct cifs_ses *ses;
+
+	spin_lock(&cifs_tcp_ses_lock);
+	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+		if (ses->Suid != smb2hdr->SessionId)
+			continue;
+		spin_unlock(&cifs_tcp_ses_lock);
+		return ses;
+	}
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	return NULL;
+}
+
+
+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;
+	struct cifs_ses *ses;
+
+	ses = smb2_find_smb_ses(smb2_pdu, server);
+	if (!ses) {
+		cifs_dbg(VFS, "%s: Could not find session\n", __func__);
+		return 0;
+	}
+
+	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,
+		ses->auth_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;
+}
+
+int
+generate_smb3signingkey(struct cifs_ses *ses)
+{
+	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(ses->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE);
+
+	rc = smb3_crypto_shash_allocate(ses->server);
+	if (rc) {
+		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
+		goto smb3signkey_ret;
+	}
+
+	rc = crypto_shash_setkey(ses->server->secmech.hmacsha256,
+		ses->auth_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(&ses->server->secmech.sdeschmacsha256->shash);
+	if (rc) {
+		cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
+		goto smb3signkey_ret;
+	}
+
+	rc = crypto_shash_update(&ses->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(&ses->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(&ses->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(&ses->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(&ses->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(&ses->server->secmech.sdeschmacsha256->shash,
+				hashptr);
+	if (rc) {
+		cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
+		goto smb3signkey_ret;
+	}
+
+	memcpy(ses->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE);
+
+smb3signkey_ret:
+	return rc;
+}
+
+int
+smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
+{
+	int i;
+	int rc = 0;
+	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;
+	struct cifs_ses *ses;
+
+	ses = smb2_find_smb_ses(smb2_pdu, server);
+	if (!ses) {
+		cifs_dbg(VFS, "%s: Could not find session\n", __func__);
+		return 0;
+	}
+
+	memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
+	memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE);
+
+	rc = crypto_shash_setkey(server->secmech.cmacaes,
+		ses->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_SESSION_SETUP) ||
+	    (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)
+{
+	unsigned int i, num = le16_to_cpu(hdr->CreditCharge);
+
+	hdr->MessageId = get_next_mid64(server);
+	/* skip message numbers according to CreditCharge field */
+	for (i = 1; i < num; i++)
+		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 = le64_to_cpu(smb_buffer->MessageId);
+		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 == CifsNew) {
+		if ((buf->Command != SMB2_SESSION_SETUP) &&
+		    (buf->Command != SMB2_NEGOTIATE))
+			return -EAGAIN;
+		/* else ok - we are setting up session */
+	}
+
+	if (ses->status == CifsExiting) {
+		if (buf->Command != SMB2_LOGOFF)
+			return -EAGAIN;
+		/* else ok - we are shutting down the 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;
+}