[CIFS] Support for setting up SMB sessions to legacy lanman servers p…

…art 2

fs/cifs/cifs_debug.c

@@ -508,7 +508,7 @@ cifs_proc_init(void)
 		pde->write_proc = multiuser_mount_write;
 
 	pde =
-	    create_proc_read_entry("ExtendedSecurity", 0, proc_fs_cifs,
+	    create_proc_read_entry("SecurityFlags", 0, proc_fs_cifs,
 				extended_security_read, NULL);
 	if (pde)
 		pde->write_proc = extended_security_write;
@@ -547,7 +547,7 @@ cifs_proc_clean(void)
 	remove_proc_entry("MultiuserMount", proc_fs_cifs);
 	remove_proc_entry("OplockEnabled", proc_fs_cifs);
 /*	remove_proc_entry("NTLMV2Enabled",proc_fs_cifs); */
-	remove_proc_entry("ExtendedSecurity",proc_fs_cifs);
+	remove_proc_entry("SecurityFlags",proc_fs_cifs);
 /*	remove_proc_entry("PacketSigningEnabled",proc_fs_cifs); */
 	remove_proc_entry("LinuxExtensionsEnabled",proc_fs_cifs);
 	remove_proc_entry("Experimental",proc_fs_cifs);

fs/cifs/cifsencrypt.c

@@ -26,6 +26,7 @@
 #include "md5.h"
 #include "cifs_unicode.h"
 #include "cifsproto.h"
+#include <linux/ctype.h>
 
 /* Calculate and return the CIFS signature based on the mac key and the smb pdu */
 /* the 16 byte signature must be allocated by the caller  */
@@ -35,6 +36,8 @@
 
 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, unsigned char *c8,
+                       unsigned char *p24);
 
 static int cifs_calculate_signature(const struct smb_hdr * cifs_pdu, 
 				    const char * key, char * signature)
@@ -45,7 +48,7 @@ static int cifs_calculate_signature(const struct smb_hdr * cifs_pdu,
 		return -EINVAL;
 
 	MD5Init(&context);
-	MD5Update(&context,key,CIFS_SESSION_KEY_SIZE+16);
+	MD5Update(&context,key,CIFS_SESS_KEY_SIZE+16);
 	MD5Update(&context,cifs_pdu->Protocol,cifs_pdu->smb_buf_length);
 	MD5Final(signature,&context);
 	return 0;
@@ -90,7 +93,7 @@ static int cifs_calc_signature2(const struct kvec * iov, int n_vec,
 		return -EINVAL;
 
 	MD5Init(&context);
-	MD5Update(&context,key,CIFS_SESSION_KEY_SIZE+16);
+	MD5Update(&context,key,CIFS_SESS_KEY_SIZE+16);
 	for(i=0;i<n_vec;i++) {
 		if(iov[i].iov_base == NULL) {
 			cERROR(1,("null iovec entry"));
@@ -204,7 +207,7 @@ int cifs_calculate_mac_key(char * key, const char * rn, const char * password)
 
 	E_md4hash(password, temp_key);
 	mdfour(key,temp_key,16);
-	memcpy(key+16,rn, CIFS_SESSION_KEY_SIZE);
+	memcpy(key+16,rn, CIFS_SESS_KEY_SIZE);
 	return 0;
 }
 
@@ -261,6 +264,37 @@ int CalcNTLMv2_partial_mac_key(struct cifsSesInfo * ses, struct nls_table * nls_
 	kfree(unicode_buf);
 	return 0;
 }
+
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+void calc_lanman_hash(struct cifsSesInfo * ses, char * lnm_session_key)
+{
+	int i;
+	char password_with_pad[CIFS_ENCPWD_SIZE];
+
+	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
+	strncpy(password_with_pad, ses->password, CIFS_ENCPWD_SIZE);
+
+	/* 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, ses->server->cryptKey, lnm_session_key);
+	/* clear password before we return/free memory */
+	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
+}
+#endif /* CIFS_WEAK_PW_HASH */
+
 void CalcNTLMv2_response(const struct cifsSesInfo * ses,char * v2_session_response)
 {
 	struct HMACMD5Context context;

fs/cifs/cifsglob.h

@@ -158,7 +158,7 @@ struct TCP_Server_Info {
 	/* 16th byte of RFC1001 workstation name is always null */
 	char workstation_RFC1001_name[SERVER_NAME_LEN_WITH_NULL];
 	__u32 sequence_number; /* needed for CIFS PDU signature */
-	char mac_signing_key[CIFS_SESSION_KEY_SIZE + 16]; 
+	char mac_signing_key[CIFS_SESS_KEY_SIZE + 16]; 
 };
 
 /*

fs/cifs/cifspdu.h

@@ -116,7 +116,8 @@
 /*
  * Size of the session key (crypto key encrypted with the password
  */
-#define CIFS_SESSION_KEY_SIZE (24)
+#define CIFS_SESS_KEY_SIZE (24)
+#define V2_SESS_KEY_SIZE (86)
 
 /*
  * Maximum user name length

fs/cifs/cifsproto.h

@@ -287,6 +287,9 @@ extern int cifs_verify_signature(struct smb_hdr *, const char * mac_key,
 extern int cifs_calculate_mac_key(char * key,const char * rn,const char * pass);
 extern int CalcNTLMv2_partial_mac_key(struct cifsSesInfo *, struct nls_table *);
 extern void CalcNTLMv2_response(const struct cifsSesInfo *,char * );
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+extern void calc_lanman_hash(struct cifsSesInfo * ses, char * lnm_session_key);
+#endif /* CIFS_WEAK_PW_HASH */
 extern int CIFSSMBCopy(int xid,
 			struct cifsTconInfo *source_tcon,
 			const char *fromName,

fs/cifs/cifssmb.c

@@ -438,12 +438,19 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
 			goto neg_err_exit;
 		} else if((pSMBr->hdr.WordCount == 13) && 
 			(pSMBr->DialectIndex == LANMAN_PROT)) {
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
 			struct lanman_neg_rsp * rsp = 
 				(struct lanman_neg_rsp *)pSMBr;
 
-
-			/* BB Mark ses struct as negotiated lanman level BB */
-			server->secType = LANMAN;
+			if((extended_security & CIFSSEC_MAY_LANMAN) || 
+				(extended_security & CIFSSEC_MAY_PLNTXT))
+				server->secType = LANMAN;
+			else {
+				cERROR(1, ("mount failed weak security disabled"
+					" in /proc/fs/cifs/SecurityFlags"));
+				rc = -EOPNOTSUPP;
+				goto neg_err_exit;
+			}	
 			server->secMode = (__u8)le16_to_cpu(rsp->SecurityMode);
 			server->maxReq = le16_to_cpu(rsp->MaxMpxCount);
 			server->maxBuf = min((__u32)le16_to_cpu(rsp->MaxBufSize),
@@ -469,6 +476,11 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
 			}
 
 			cFYI(1,("LANMAN negotiated")); /* BB removeme BB */
+#else /* weak security disabled */
+			cERROR(1,("mount failed, cifs module not built with "
+				"CIFS_WEAK_PW_HASH support"));
+			rc = -EOPNOTSUPP;
+#endif /* WEAK_PW_HASH */
 			goto neg_err_exit;
 		} else if(pSMBr->hdr.WordCount != 17) {
 			/* unknown wct */
@@ -479,8 +491,13 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
 		server->secMode = pSMBr->SecurityMode;
 		if((server->secMode & SECMODE_USER) == 0)
 			cFYI(1,("share mode security"));
-		server->secType = NTLM; /* BB override default for
-					   NTLMv2 or kerberos v5 */
+
+		if(extended_security & CIFSSEC_MUST_NTLMV2)
+			server->secType = NTLMv2;
+		else
+			server->secType = NTLM;
+		/* else krb5 ... */
+
 		/* one byte - no need to convert this or EncryptionKeyLen
 		   from little endian */
 		server->maxReq = le16_to_cpu(pSMBr->MaxMpxCount);

fs/cifs/connect.c

@@ -1990,7 +1990,7 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 
 static int
 CIFSSessSetup(unsigned int xid, struct cifsSesInfo *ses,
-	      char session_key[CIFS_SESSION_KEY_SIZE],
+	      char session_key[CIFS_SESS_KEY_SIZE],
 	      const struct nls_table *nls_codepage)
 {
 	struct smb_hdr *smb_buffer;
@@ -2048,15 +2048,15 @@ CIFSSessSetup(unsigned int xid, struct cifsSesInfo *ses,
 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 
 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 
-		cpu_to_le16(CIFS_SESSION_KEY_SIZE);
+		cpu_to_le16(CIFS_SESS_KEY_SIZE);
 
 	pSMB->req_no_secext.CaseSensitivePasswordLength =
-	    cpu_to_le16(CIFS_SESSION_KEY_SIZE);
+	    cpu_to_le16(CIFS_SESS_KEY_SIZE);
 	bcc_ptr = pByteArea(smb_buffer);
-	memcpy(bcc_ptr, (char *) session_key, CIFS_SESSION_KEY_SIZE);
-	bcc_ptr += CIFS_SESSION_KEY_SIZE;
-	memcpy(bcc_ptr, (char *) session_key, CIFS_SESSION_KEY_SIZE);
-	bcc_ptr += CIFS_SESSION_KEY_SIZE;
+	memcpy(bcc_ptr, (char *) session_key, CIFS_SESS_KEY_SIZE);
+	bcc_ptr += CIFS_SESS_KEY_SIZE;
+	memcpy(bcc_ptr, (char *) session_key, CIFS_SESS_KEY_SIZE);
+	bcc_ptr += CIFS_SESS_KEY_SIZE;
 
 	if (ses->capabilities & CAP_UNICODE) {
 		if ((long) bcc_ptr % 2) { /* must be word aligned for Unicode */
@@ -3004,14 +3004,14 @@ CIFSNTLMSSPAuthSessSetup(unsigned int xid, struct cifsSesInfo *ses,
 	SecurityBlob->LmChallengeResponse.Buffer = 0;
 
 	SecurityBlob->NtChallengeResponse.Length =
-	    cpu_to_le16(CIFS_SESSION_KEY_SIZE);
+	    cpu_to_le16(CIFS_SESS_KEY_SIZE);
 	SecurityBlob->NtChallengeResponse.MaximumLength =
-	    cpu_to_le16(CIFS_SESSION_KEY_SIZE);
-	memcpy(bcc_ptr, ntlm_session_key, CIFS_SESSION_KEY_SIZE);
+	    cpu_to_le16(CIFS_SESS_KEY_SIZE);
+	memcpy(bcc_ptr, ntlm_session_key, CIFS_SESS_KEY_SIZE);
 	SecurityBlob->NtChallengeResponse.Buffer =
 	    cpu_to_le32(SecurityBlobLength);
-	SecurityBlobLength += CIFS_SESSION_KEY_SIZE;
-	bcc_ptr += CIFS_SESSION_KEY_SIZE;
+	SecurityBlobLength += CIFS_SESS_KEY_SIZE;
+	bcc_ptr += CIFS_SESS_KEY_SIZE;
 
 	if (ses->capabilities & CAP_UNICODE) {
 		if (domain == NULL) {
@@ -3350,22 +3350,33 @@ CIFSTCon(unsigned int xid, struct cifsSesInfo *ses,
 	bcc_ptr = &pSMB->Password[0];
 	if((ses->server->secMode) & SECMODE_USER) {
 		pSMB->PasswordLength = cpu_to_le16(1);	/* minimum */
+		*bcc_ptr = 0; /* password is null byte */
 		bcc_ptr++;              /* skip password */
+		/* already aligned so no need to do it below */
 	} else {
-		pSMB->PasswordLength = cpu_to_le16(CIFS_SESSION_KEY_SIZE);
+		pSMB->PasswordLength = cpu_to_le16(CIFS_SESS_KEY_SIZE);
 		/* BB FIXME add code to fail this if NTLMv2 or Kerberos
 		   specified as required (when that support is added to
 		   the vfs in the future) as only NTLM or the much
-		   weaker LANMAN (which we do not send) is accepted
+		   weaker LANMAN (which we do not send by default) is accepted
 		   by Samba (not sure whether other servers allow
 		   NTLMv2 password here) */
+#ifdef CONFIG_CIFS_WEAK_PW_HASH
+		if((extended_security & CIFSSEC_MAY_LANMAN) && 
+			(ses->server->secType == LANMAN))
+			calc_lanman_hash(ses, bcc_ptr);
+		else
+#endif /* CIFS_WEAK_PW_HASH */
 		SMBNTencrypt(ses->password,
 			     ses->server->cryptKey,
 			     bcc_ptr);
 
-		bcc_ptr += CIFS_SESSION_KEY_SIZE;
-		*bcc_ptr = 0;
-		bcc_ptr++; /* align */
+		bcc_ptr += CIFS_SESS_KEY_SIZE;
+		if(ses->capabilities & CAP_UNICODE) {
+			/* must align unicode strings */
+			*bcc_ptr = 0; /* null byte password */
+			bcc_ptr++;
+		}
 	}
 
 	if(ses->server->secMode & 
@@ -3507,7 +3518,7 @@ int cifs_setup_session(unsigned int xid, struct cifsSesInfo *pSesInfo,
 					   struct nls_table * nls_info)
 {
 	int rc = 0;
-	char ntlm_session_key[CIFS_SESSION_KEY_SIZE];
+	char ntlm_session_key[CIFS_SESS_KEY_SIZE];
 	int ntlmv2_flag = FALSE;
 	int first_time = 0;
 

fs/cifs/netmisc.c

@@ -84,7 +84,7 @@ static const struct smb_to_posix_error mapping_table_ERRDOS[] = {
 
 static const struct smb_to_posix_error mapping_table_ERRSRV[] = {
 	{ERRerror, -EIO},
-	{ERRbadpw, -EPERM},
+	{ERRbadpw, -EACCES},  /* was EPERM */
 	{ERRbadtype, -EREMOTE},
 	{ERRaccess, -EACCES},
 	{ERRinvtid, -ENXIO},