1 files changed, 113 insertions, 0 deletions
diff --git a/test/packetdrill/mpls.h b/test/packetdrill/mpls.h
new file mode 100644
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--- /dev/null
+++ b/test/packetdrill/mpls.h
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+/*
+ * Author: ncardwell@google.com (Neal Cardwell)
+ *
+ * Our own MPLS header declarations, so we have something that's
+ * portable and somewhat more readable than a typical system header
+ * file.
+ *
+ * We cannot include the kernel's MPLS .h files because this tool tries
+ * to compile and work for basically any Linux/BSD kernel version. So
+ * we declare our own version of various MPLS-related definitions here.
+ */
+
+#ifndef __MPLS_HEADERS_H__
+#define __MPLS_HEADERS_H__
+
+#include <stdlib.h>
+#include "types.h"
+
+/* On-the-wire MPLS "label stack entry", per RFC 3032 and RFC 5462. */
+struct mpls {
+	__be32 entry;
+};
+
+/* Bit-shifting macros to access MPLS fields (the label straddles byte
+ * boundaries so there's no simple/clean way to use bit fields).
+ */
+#define MPLS_LABEL_MASK		0xfffff000	/* label */
+#define MPLS_LABEL_SHIFT	12
+#define MPLS_TC_MASK		0x00000e00	/* traffic class */
+#define MPLS_TC_SHIFT		9
+#define MPLS_STACK_MASK		0x00000100	/* is stack bottom? */
+#define MPLS_STACK_SHIFT	8
+#define MPLS_TTL_MASK		0x000000ff	/* time to live */
+#define MPLS_TTL_SHIFT		0
+
+/* Return the label from an MPLS label stack entry. */
+static inline u32 mpls_entry_label(const struct mpls *mpls)
+{
+	return (ntohl(mpls->entry) & MPLS_LABEL_MASK) >> MPLS_LABEL_SHIFT;
+}
+
+/* Return the traffic class from an MPLS label stack entry. */
+static inline u8 mpls_entry_tc(const struct mpls *mpls)
+{
+	return (ntohl(mpls->entry) & MPLS_TC_MASK) >> MPLS_TC_SHIFT;
+}
+
+/* Return the "is stack bottom?" bit from an MPLS label stack entry. */
+static inline bool mpls_entry_stack(const struct mpls *mpls)
+{
+	return (ntohl(mpls->entry) & MPLS_STACK_MASK) >> MPLS_STACK_SHIFT;
+}
+
+/* Return the TTL from an MPLS label stack entry. */
+static inline u8 mpls_entry_ttl(const struct mpls *mpls)
+{
+	return (ntohl(mpls->entry) & MPLS_TTL_MASK) >> MPLS_TTL_SHIFT;
+}
+
+/* Fill in an MPLS label stack entry with the given field values. */
+static inline void mpls_entry_set(u32 label, u8 traffic_class,
+				  bool is_stack_bottom, u8 ttl,
+				  struct mpls *mpls)
+{
+	mpls->entry = htonl((label		<< MPLS_LABEL_SHIFT)	|
+			    (traffic_class	<< MPLS_TC_SHIFT)	|
+			    (is_stack_bottom	<< MPLS_STACK_SHIFT)	|
+			    (ttl		<< MPLS_TTL_SHIFT));
+}
+
+/* Parse-time representation of an MPLS label stack entry. */
+#define MPLS_STACK_MAX_ENTRIES	6	/* maximum number of label entries */
+struct mpls_stack {
+	struct mpls entries[MPLS_STACK_MAX_ENTRIES];
+	int length;		/* number of MPLS label stack entries */
+};
+
+/* Allocate and initialize a new MPLS label stack as empty. */
+static inline struct mpls_stack *mpls_stack_new(void)
+{
+	return calloc(1, sizeof(struct mpls_stack));
+}
+
+/* Appends the given MPLS label stack entry to the given stack. Returns
+ * STATUS_OK on success, or STATUS_ERR on error (if the label stack is full).
+ */
+static inline int mpls_stack_append(struct mpls_stack *stack, struct mpls mpls)
+{
+	if (stack->length >= ARRAY_SIZE(stack->entries))
+		return STATUS_ERR;
+	stack->entries[stack->length++] = mpls;
+	return STATUS_OK;
+}
+
+#endif /* __MPLS_HEADERS_H__ */