Validate Negotiate Updated Patch

Commit Message

Steve French Nov. 19, 2013, 4:56 a.m. UTC

This patch oopses in the calc signature code (will fix that tomorrow)
since the signing structs aren't initialized when we think we don't
have to do signing (but with SMB3 you always have to be able to do
signing) but is progress in validating negotiate info via the SMB3
fsctl.  Feedback/comments welcome.

Patch

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index d9ea7ad..f918a99 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -384,6 +384,7 @@  struct smb_version_operations {
 	int (*clone_range)(const unsigned int, struct cifsFileInfo *src_file,
 			struct cifsFileInfo *target_file, u64 src_off, u64 len,
 			u64 dest_off);
+	int (*validate_negotiate)(const unsigned int, struct cifs_tcon *);
 };
 
 struct smb_version_values {
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index a3968ee..757da3e 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1319,6 +1319,7 @@  struct smb_version_operations smb30_operations = {
 	.create_lease_buf = smb3_create_lease_buf,
 	.parse_lease_buf = smb3_parse_lease_buf,
 	.clone_range = smb2_clone_range,
+	.validate_negotiate = smb3_validate_negotiate,
 };
 
 struct smb_version_values smb20_values = {
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 1e136ee..8b9cc99 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -454,6 +454,70 @@  neg_exit:
 	return rc;
 }
 
+int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
+{
+	int rc = 0;
+	struct validate_negotiate_info_req vneg_inbuf;
+	struct validate_negotiate_info_rsp *pneg_rsp;
+	u32 rsplen;
+
+	cifs_dbg(VFS, "validate negotiate ");
+	vneg_inbuf.Capabilities =
+			cpu_to_le32(tcon->ses->server->vals->req_capabilities);
+	memcpy(vneg_inbuf.Guid, cifs_client_guid, SMB2_CLIENT_GUID_SIZE);
+
+	if (tcon->ses->sign)
+		vneg_inbuf.SecurityMode =
+			cpu_to_le16(SMB2_NEGOTIATE_SIGNING_REQUIRED);
+	else if (global_secflags & CIFSSEC_MAY_SIGN)
+		vneg_inbuf.SecurityMode =
+			cpu_to_le16(SMB2_NEGOTIATE_SIGNING_ENABLED);
+	else
+		vneg_inbuf.SecurityMode = 0;
+
+	vneg_inbuf.DialectCount = cpu_to_le16(1);
+	vneg_inbuf.Dialects[0] =
+		cpu_to_le16(tcon->ses->server->vals->protocol_id);
+
+	/* BB need to force signing on this request */
+	rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
+		FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */,
+		(char *)&vneg_inbuf, sizeof(struct validate_negotiate_info_req),
+		(char **)&pneg_rsp, &rsplen);
+
+	if (rc != 0) {
+		cifs_dbg(VFS, "validate protocol negotiate failed: %d\n", rc);
+		return -EIO;
+	}
+
+	if (rsplen != sizeof(struct validate_negotiate_info_rsp)) {
+		cifs_dbg(VFS, "invalid size of protocol negotiate response\n");
+		return -EIO;
+	}
+
+	/* check validate negotiate info response matches what we got earlier */
+	if (pneg_rsp->Dialect !=
+			cpu_to_le16(tcon->ses->server->vals->protocol_id))
+		goto vneg_out;
+
+	if (pneg_rsp->SecurityMode != cpu_to_le16(tcon->ses->server->sec_mode))
+		goto vneg_out;
+
+	/* do not validate server guid because not saved at negprot time yet */
+
+	if ((le32_to_cpu(pneg_rsp->Capabilities) | SMB2_NT_FIND |
+	      SMB2_LARGE_FILES) != tcon->ses->server->capabilities)
+		goto vneg_out;
+
+	/* validate negotiate successful */
+	cifs_dbg(FYI, "validate negotiate info successful\n");
+	return 0;
+
+vneg_out:
+	cifs_dbg(VFS, "protocol revalidation - security settings mismatch\n");
+	return -EIO;
+}
+
 int
 SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses,
 		const struct nls_table *nls_cp)
@@ -829,6 +893,8 @@  SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
 	    ((tcon->share_flags & SHI1005_FLAGS_DFS) == 0))
 		cifs_dbg(VFS, "DFS capability contradicts DFS flag\n");
 	init_copy_chunk_defaults(tcon);
+	if (tcon->ses->server->ops->validate_negotiate)
+		rc = tcon->ses->server->ops->validate_negotiate(xid, tcon);
 tcon_exit:
 	free_rsp_buf(resp_buftype, rsp);
 	kfree(unc_path);
@@ -1161,6 +1227,10 @@  SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 	if (rc)
 		return rc;
 
+	/* validate negotiate is always signed */
+	if (opcode == FSCTL_VALIDATE_NEGOTIATE_INFO)
+		req->hdr.Flags |= SMB2_FLAGS_SIGNED;
+
 	req->CtlCode = cpu_to_le32(opcode);
 	req->PersistentFileId = persistent_fid;
 	req->VolatileFileId = volatile_fid;
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index f88320b..2022c54 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -577,13 +577,19 @@  struct copychunk_ioctl_rsp {
 	__le32 TotalBytesWritten;
 } __packed;
 
-/* Response and Request are the same format */
-struct validate_negotiate_info {
+struct validate_negotiate_info_req {
 	__le32 Capabilities;
 	__u8   Guid[SMB2_CLIENT_GUID_SIZE];
 	__le16 SecurityMode;
 	__le16 DialectCount;
-	__le16 Dialect[1];
+	__le16 Dialects[1]; /* dialect (someday maybe list) client asked for */
+} __packed;
+
+struct validate_negotiate_info_rsp {
+	__le32 Capabilities;
+	__u8   Guid[SMB2_CLIENT_GUID_SIZE];
+	__le16 SecurityMode;
+	__le16 Dialect; /* Dialect in use for the connection */
 } __packed;
 
 #define RSS_CAPABLE	0x00000001
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index b4eea10..93adc64 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -162,5 +162,6 @@  extern int smb2_lockv(const unsigned int xid, struct cifs_tcon *tcon,
 		      struct smb2_lock_element *buf);
 extern int SMB2_lease_break(const unsigned int xid, struct cifs_tcon *tcon,
 			    __u8 *lease_key, const __le32 lease_state);
+extern int smb3_validate_negotiate(const unsigned int, struct cifs_tcon *);
 
 #endif			/* _SMB2PROTO_H */
diff --git a/fs/cifs/smbfsctl.h b/fs/cifs/smbfsctl.h
index a4b2391f..0e538b5 100644
--- a/fs/cifs/smbfsctl.h
+++ b/fs/cifs/smbfsctl.h
@@ -90,7 +90,7 @@ 
 #define FSCTL_LMR_REQUEST_RESILIENCY 0x001401D4 /* BB add struct */
 #define FSCTL_LMR_GET_LINK_TRACK_INF 0x001400E8 /* BB add struct */
 #define FSCTL_LMR_SET_LINK_TRACK_INF 0x001400EC /* BB add struct */
-#define FSCTL_VALIDATE_NEGOTIATE_INFO 0x00140204 /* BB add struct */
+#define FSCTL_VALIDATE_NEGOTIATE_INFO 0x00140204
 /* Perform server-side data movement */
 #define FSCTL_SRV_COPYCHUNK 0x001440F2
 #define FSCTL_SRV_COPYCHUNK_WRITE 0x001480F2