1 files changed, 70 insertions, 25 deletions

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index f230571a7ab3..79358e341fd2 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -138,8 +138,7 @@ static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
 
-	if (ses->server->sec_mode &
-	    (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
+	if (ses->server->sign)
 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
 
 	if (ses->capabilities & CAP_UNICODE) {
@@ -310,11 +309,10 @@ decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
 	return;
 }
 
-static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
-			       struct cifs_ses *ses,
-			       const struct nls_table *nls_cp)
+static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
+				struct cifs_ses *ses,
+				const struct nls_table *nls_cp)
 {
-	int rc = 0;
 	int len;
 	char *bcc_ptr = *pbcc_area;
 
@@ -322,24 +320,22 @@ static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
 
 	len = strnlen(bcc_ptr, bleft);
 	if (len >= bleft)
-		return rc;
+		return;
 
 	kfree(ses->serverOS);
 
 	ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
 	if (ses->serverOS)
 		strncpy(ses->serverOS, bcc_ptr, len);
-	if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
+	if (strncmp(ses->serverOS, "OS/2", 4) == 0)
 		cifs_dbg(FYI, "OS/2 server\n");
-			ses->flags |= CIFS_SES_OS2;
-	}
 
 	bcc_ptr += len + 1;
 	bleft -= len + 1;
 
 	len = strnlen(bcc_ptr, bleft);
 	if (len >= bleft)
-		return rc;
+		return;
 
 	kfree(ses->serverNOS);
 
@@ -352,7 +348,7 @@ static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
 
 	len = strnlen(bcc_ptr, bleft);
 	if (len > bleft)
-		return rc;
+		return;
 
 	/* No domain field in LANMAN case. Domain is
 	   returned by old servers in the SMB negprot response */
@@ -360,8 +356,6 @@ static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
 	   but thus do return domain here we could add parsing
 	   for it later, but it is not very important */
 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
-
-	return rc;
 }
 
 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
@@ -432,8 +426,7 @@ void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
-	if (ses->server->sec_mode &
-			(SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
+	if (ses->server->sign) {
 		flags |= NTLMSSP_NEGOTIATE_SIGN;
 		if (!ses->server->session_estab)
 			flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
@@ -471,8 +464,7 @@ int build_ntlmssp_auth_blob(unsigned char *pbuffer,
 		NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
-	if (ses->server->sec_mode &
-	   (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
+	if (ses->server->sign) {
 		flags |= NTLMSSP_NEGOTIATE_SIGN;
 		if (!ses->server->session_estab)
 			flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
@@ -558,6 +550,56 @@ setup_ntlmv2_ret:
 	return rc;
 }
 
+enum securityEnum
+select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
+{
+	switch (server->negflavor) {
+	case CIFS_NEGFLAVOR_EXTENDED:
+		switch (requested) {
+		case Kerberos:
+		case RawNTLMSSP:
+			return requested;
+		case Unspecified:
+			if (server->sec_ntlmssp &&
+			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
+				return RawNTLMSSP;
+			if ((server->sec_kerberos || server->sec_mskerberos) &&
+			    (global_secflags & CIFSSEC_MAY_KRB5))
+				return Kerberos;
+			/* Fallthrough */
+		default:
+			return Unspecified;
+		}
+	case CIFS_NEGFLAVOR_UNENCAP:
+		switch (requested) {
+		case NTLM:
+		case NTLMv2:
+			return requested;
+		case Unspecified:
+			if (global_secflags & CIFSSEC_MAY_NTLMV2)
+				return NTLMv2;
+			if (global_secflags & CIFSSEC_MAY_NTLM)
+				return NTLM;
+			/* Fallthrough */
+		default:
+			return Unspecified;
+		}
+	case CIFS_NEGFLAVOR_LANMAN:
+		switch (requested) {
+		case LANMAN:
+			return requested;
+		case Unspecified:
+			if (global_secflags & CIFSSEC_MAY_LANMAN)
+				return LANMAN;
+			/* Fallthrough */
+		default:
+			return Unspecified;
+		}
+	default:
+		return Unspecified;
+	}
+}
+
 int
 CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	       const struct nls_table *nls_cp)
@@ -579,11 +621,18 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	u16 blob_len;
 	char *ntlmsspblob = NULL;
 
-	if (ses == NULL)
+	if (ses == NULL) {
+		WARN(1, "%s: ses == NULL!", __func__);
 		return -EINVAL;
+	}
 
-	type = ses->server->secType;
+	type = select_sectype(ses->server, ses->sectype);
 	cifs_dbg(FYI, "sess setup type %d\n", type);
+	if (type == Unspecified) {
+		cifs_dbg(VFS, "Unable to select appropriate authentication method!");
+		return -EINVAL;
+	}
+
 	if (type == RawNTLMSSP) {
 		/* if memory allocation is successful, caller of this function
 		 * frees it.
@@ -643,8 +692,6 @@ ssetup_ntlmssp_authenticate:
 	}
 	bcc_ptr = str_area;
 
-	ses->flags &= ~CIFS_SES_LANMAN;
-
 	iov[1].iov_base = NULL;
 	iov[1].iov_len = 0;
 
@@ -668,7 +715,6 @@ ssetup_ntlmssp_authenticate:
 				 ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
 					true : false, lnm_session_key);
 
-		ses->flags |= CIFS_SES_LANMAN;
 		memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
 		bcc_ptr += CIFS_AUTH_RESP_SIZE;
 
@@ -938,8 +984,7 @@ ssetup_ntlmssp_authenticate:
 		}
 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
 	} else {
-		rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
-					 ses, nls_cp);
+		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
 	}
 
 ssetup_exit: