Signing fixes part 2

fs/cifs/Makefile

@@ -3,4 +3,4 @@
 #
 obj-$(CONFIG_CIFS) += cifs.o
 
-cifs-objs := cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o inode.o link.o misc.o netmisc.o smbdes.o smbencrypt.o transport.o asn1.o md4.o md5.o cifs_unicode.o nterr.o xattr.o
+cifs-objs := cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o inode.o link.o misc.o netmisc.o smbdes.o smbencrypt.o transport.o asn1.o md4.o md5.o cifs_unicode.o nterr.o xattr.o cifsencrypt.o

fs/cifs/cifsencrypt.c

+/*
+ *   fs/cifs/cifsencrypt.c
+ *
+ *   Copyright (c) International Business Machines  Corp., 2003
+ *   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 "cifspdu.h"
+#include "cifsglob.h" 
+#include "cifs_debug.h"
+
+/* Calculate and return the CIFS signature based on the mac key and the smb pdu */
+/* the eight byte signature must be allocated by the caller. */
+/* Note that the smb header signature field on input contains the  
+	sequence number before this function is called */
+	
+static int cifs_calculate_signature(const struct smb_hdr * cifs_pdu, const char * mac_key, char * signature)
+{
+
+	if((cifs_pdu == NULL) || (signature == NULL))
+		return -EINVAL;
+
+	/* MD5(mac_key, text) */
+	/* return 1st eight bytes in signature */
+
+	return 0;
+}
+
+int cifs_sign_smb(struct smb_hdr * cifs_pdu, struct cifsSesInfo * ses)
+{
+	int rc = 0;
+	char smb_signature[8];
+
+	/* BB remember to initialize sequence number elsewhere and initialize mac_signing key elsewhere BB */
+	/* BB remember to add code to save expected sequence number in midQ entry BB */
+
+	if((cifs_pdu == NULL) || (ses == NULL))
+		return -EINVAL;
+
+	if((le32_to_cpu(cifs_pdu->Flags2) & SMBFLG2_SECURITY_SIGNATURE) == 0) 
+		return rc;
+
+	cifs_pdu->Signature.Sequence.SequenceNumber = ses->sequence_number;
+	cifs_pdu->Signature.Sequence.Reserved = 0;
+	rc = cifs_calculate_signature(cifs_pdu, ses->mac_signing_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(const struct smb_hdr * cifs_pdu, const char * mac_key,
+	__u32 expected_sequence_number)
+{
+	unsigned int rc = 0;
+
+        if((cifs_pdu == NULL) || (mac_key == NULL))
+                return -EINVAL;
+	
+	/* BB no need to verify negprot or if flag is not on for session (or for frame?? */
+	/* BB what if signatures are supposed to be on for session but server does not
+		send one? BB */
+	/* BB also do not verify oplock breaks for signature */
+
+	return rc;
+} 

fs/cifs/cifsglob.h

@@ -149,7 +149,9 @@ struct cifsSesInfo {
 	struct TCP_Server_Info *server;	/* pointer to server info */
 	atomic_t inUse;		/* # of CURRENT users of this ses */
 	enum statusEnum status;
+	__u32 sequence_number;  /* needed for CIFS PDU signature */
 	__u16 ipc_tid;		/* special tid for connection to IPC share */
+	char mac_signing_key[CIFS_SESSION_KEY_SIZE];	
 	char *serverOS;		/* name of operating system underlying the server */
 	char *serverNOS;	/* name of network operating system that the server is running */
 	char *serverDomain;	/* security realm of server */
@@ -249,6 +251,7 @@ struct mid_q_entry {
 	struct list_head qhead;	/* mids waiting on reply from this server */
 	__u16 mid;		/* multiplex id */
 	__u16 pid;		/* process id */
+	__u32 sequence_number;  /* for CIFS signing */
 	__u16 command;		/* smb command code */
 	struct timeval when_sent;	/* time when smb sent */
 	struct cifsSesInfo *ses;	/* smb was sent to this server */

fs/cifs/cifspdu.h

@@ -307,7 +307,13 @@ struct smb_hdr {
 	__u8 Flags;
 	__u16 Flags2;		/* note: le */
 	__u16 PidHigh;		/* note: le */
-	__u8 SecuritySignature[8];	/* note le */
+	union {
+		struct {
+			__u32 SequenceNumber;  /* le */
+			__u32 Reserved; /* zero */
+		} Sequence;
+		__u8 SecuritySignature[8];	/* le */
+	} Signature;
 	__u8 pad[2];
 	__u16 Tid;
 	__u16 Pid;		/* note: le */

fs/cifs/cifsproto.h

@@ -79,8 +79,7 @@ extern int setup_session(unsigned int xid, struct cifsSesInfo *pSesInfo,
 			struct nls_table * nls_info);
 extern int CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses);
 extern int CIFSSessSetup(unsigned int xid, struct cifsSesInfo *ses,
-			char *session_key, char *ntlm_session_key,
-			const struct nls_table *);
+			char *ntlm_session_key, const struct nls_table *);
 extern int CIFSSpnegoSessSetup(unsigned int xid, struct cifsSesInfo *ses,
 			char *SecurityBlob,int SecurityBlobLength,
 			const struct nls_table *);
@@ -226,6 +225,10 @@ extern void tconInfoFree(struct cifsTconInfo *);
 extern int cifs_demultiplex_thread(struct TCP_Server_Info *);
 extern int cifs_reconnect(struct TCP_Server_Info *server);
 
+extern int cifs_sign_smb(struct smb_hdr *, struct cifsSesInfo *);
+extern int cifs_verify_signature(const struct smb_hdr *, const char * mac_key,
+	__u32 expected_sequence_number);
+
 /* BB routines below not implemented yet BB */
 
 extern int CIFSBuildServerList(int xid, char *serverBufferList,

fs/cifs/cifssmb.c

@@ -106,9 +106,6 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
 	pSMB->hdr.Flags2 |= SMBFLG2_UNICODE;
 	if (extended_security)
 		pSMB->hdr.Flags2 |= SMBFLG2_EXT_SEC;
-	if (sign_CIFS_PDUs) {
-		pSMB->hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
-	}
 
 	pSMB->ByteCount = strlen(protocols[0].name) + 1;
 	strncpy(pSMB->DialectsArray, protocols[0].name, 30);	
@@ -260,10 +257,13 @@ CIFSSMBLogoff(const int xid, struct cifsSesInfo *ses)
 		up(&ses->sesSem);
 		return -EBUSY;
 	}
-	if(ses->server->secMode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
-		pSMB->hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
 	rc = smb_init(SMB_COM_LOGOFF_ANDX, 2, 0 /* no tcon anymore */,
 		 (void **) &pSMB, (void **) &smb_buffer_response);
+
+        if(ses->server->secMode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
+                pSMB->hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
 	if (rc) {
 		up(&ses->sesSem);
 		return rc;
@@ -1657,8 +1657,6 @@ CIFSGetDFSRefer(const int xid, struct cifsSesInfo *ses,
 	if (ses->capabilities & CAP_DFS) {
 		pSMB->hdr.Flags2 |= SMBFLG2_DFS;
 	}
-	if(ses->server->secMode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
-		pSMB->hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
 
 	if (ses->capabilities & CAP_UNICODE) {
 		pSMB->hdr.Flags2 |= SMBFLG2_UNICODE;

fs/cifs/connect.c

@@ -641,6 +641,7 @@ int setup_session(unsigned int xid, struct cifsSesInfo *pSesInfo, struct nls_tab
 	if(pSesInfo->server->maxBuf == 0) /* no need to send on reconnect */
 		rc = CIFSSMBNegotiate(xid, pSesInfo);
 	pSesInfo->capabilities = pSesInfo->server->capabilities;
+	pSesInfo->sequence_number = 0;
 	if (!rc) {
 		cFYI(1,("Security Mode: 0x%x Capabilities: 0x%x Time Zone: %d",
 			pSesInfo->server->secMode,
@@ -690,9 +691,7 @@ int setup_session(unsigned int xid, struct cifsSesInfo *pSesInfo, struct nls_tab
 				pSesInfo->server->cryptKey,
 				ntlm_session_key);
 			rc = CIFSSessSetup(xid, pSesInfo,
-				session_key,
-				ntlm_session_key,
-				nls_info);
+				ntlm_session_key, nls_info);
 		}
 		if (rc) {
 			cERROR(1,("Send error in SessSetup = %d",rc));
@@ -1024,7 +1023,6 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 int
 CIFSSessSetup(unsigned int xid, struct cifsSesInfo *ses,
 	      char session_key[CIFS_SESSION_KEY_SIZE],
-	      char session_key2[CIFS_SESSION_KEY_SIZE],
 	      const struct nls_table *nls_codepage)
 {
 	struct smb_hdr *smb_buffer;
@@ -1081,9 +1079,9 @@ CIFSSessSetup(unsigned int xid, struct cifsSesInfo *ses,
 	pSMB->req_no_secext.CaseSensitivePasswordLength =
 	    cpu_to_le16(CIFS_SESSION_KEY_SIZE);
 	bcc_ptr = pByteArea(smb_buffer);
-	/* memcpy(bcc_ptr, (char *) session_key, CIFS_SESSION_KEY_SIZE);
+	/* memcpy(bcc_ptr, (char *) lm_session_key, CIFS_SESSION_KEY_SIZE);
 	   bcc_ptr += CIFS_SESSION_KEY_SIZE; */
-	memcpy(bcc_ptr, (char *) session_key2, CIFS_SESSION_KEY_SIZE);
+	memcpy(bcc_ptr, (char *) session_key, CIFS_SESSION_KEY_SIZE);
 	bcc_ptr += CIFS_SESSION_KEY_SIZE;
 
 	if (ses->capabilities & CAP_UNICODE) {
@@ -1094,7 +1092,7 @@ CIFSSessSetup(unsigned int xid, struct cifsSesInfo *ses,
 		if(user == NULL)
 			bytes_returned = 0; /* skill null user */
         else
-		    bytes_returned =
+		bytes_returned =
 		        cifs_strtoUCS((wchar_t *) bcc_ptr, user, 100, nls_codepage);
 		bcc_ptr += 2 * bytes_returned;	/* convert num 16 bit words to bytes */
 		bcc_ptr += 2;	/* trailing null */

fs/cifs/smbencrypt.c

@@ -520,7 +520,7 @@ cli_caclulate_sign_mac(struct smb_hdr *outbuf, __u8 * mac_key,
 		  be32_to_cpu(outbuf->smb_buf_length));
 	MD5Final(calc_md5_mac, &md5_ctx);
 
-	memcpy(outbuf->SecuritySignature, calc_md5_mac, 8);
+	memcpy(outbuf->Signature.SecuritySignature, calc_md5_mac, 8);
 	(*send_seq_num)++;
 	*reply_seq_num = *send_seq_num;
 	(*send_seq_num)++;

fs/cifs/transport.c

@@ -154,12 +154,8 @@ smb_send(struct socket *ssocket, struct smb_hdr *smb_buffer,
 
 	/* smb header is converted in header_assemble. bcc and rest of SMB word
 	   area, and byte area if necessary, is converted to littleendian in 
-	   cifssmb.c and RFC1001 len is converted to bigendian in smb_send */
-	if (smb_buf_length > 12)
-		smb_buffer->Flags2 = cpu_to_le16(smb_buffer->Flags2);
-
-	/* if(smb_buffer->Flags2 & SMBFLG2_SECURITY_SIGNATURE)
-		sign_smb(smb_buffer); */ /* BB enable when signing tested more */
+	   cifssmb.c and RFC1001 len is converted to bigendian in smb_send 
+	   Flags2 is converted in SendReceive */
 
 	smb_buffer->smb_buf_length = cpu_to_be32(smb_buffer->smb_buf_length);
 	cFYI(1, ("Sending smb of length %d ", smb_buf_length));
@@ -200,6 +196,12 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
 		DeleteMidQEntry(midQ);
 		return -EIO;
 	}
+
+        if (in_buf->smb_buf_length > 12)
+                in_buf->Flags2 = cpu_to_le16(in_buf->Flags2);
+
+        rc = cifs_sign_smb(in_buf, ses);
+
 	midQ->midState = MID_REQUEST_SUBMITTED;
 	rc = smb_send(ses->server->ssocket, in_buf, in_buf->smb_buf_length,
 		      (struct sockaddr *) &(ses->server->sockAddr));
@@ -247,9 +249,11 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
 			memcpy(out_buf, midQ->resp_buf,
 			       receive_len +
 			       4 /* include 4 byte RFC1001 header */ );
-			/* convert the length back to a form that we can use */
 
+/* int cifs_verify_signature(out_buf, ses->mac_signing_key,
+        __u32 expected_sequence_number); */
 			dump_smb(out_buf, 92);
+			/* convert the length into a more usable form */
 			out_buf->smb_buf_length =
 			    be32_to_cpu(out_buf->smb_buf_length);
 			if (out_buf->smb_buf_length > 12)