BIER

- see draft-ietf-bier-mpls-encapsulation-10
- midpoint, head and tail functions
- supported payload protocols; IPv4 and IPv6 only.

Change-Id: I59d7363bb6fdfdce8e4016a68a9c8f5a5e5791cb
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 109 insertions, 0 deletions

diff --git a/src/vnet/bier/bier_bit_string.c b/src/vnet/bier/bier_bit_string.c
new file mode 100644
index 00000000000..aa42e083be8
--- /dev/null
+++ b/src/vnet/bier/bier_bit_string.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/vnet.h>
+
+#include <vnet/bier/bier_types.h>
+#include <vnet/bier/bier_bit_string.h>
+
+/*
+ * the first bit in the first byte is bit position 1.
+ * bit position 0 is not valid
+ */
+#define BIER_GET_STRING_POS(_bp, _byte, _bit, _str)             \
+{                                                               \
+    _bp--;                                                      \
+    _byte = ((BIER_BBS_LEN_TO_BUCKETS((_str)->bbs_len) - 1 ) -  \
+             (_bp / BIER_BIT_MASK_BITS_PER_BUCKET));            \
+    _bit = _bp % BIER_BIT_MASK_BITS_PER_BUCKET;                 \
+}
+
+static inline int
+bier_bit_pos_is_valid (bier_bp_t bp,  const bier_bit_string_t *bbs)
+{
+    if (!((bp <= BIER_BBS_LEN_TO_BITS((bbs)->bbs_len)) &&
+          (bp >= 1))) {
+        return (0);
+    }
+    return (1);
+}
+
+/*
+ * Validate a bit poistion
+ */
+#define BIER_BIT_POS_IS_VALID(_bp, _str)                                \
+{                                                                       \
+    if (!bier_bit_pos_is_valid(_bp, _str)) return;                      \
+}
+
+void
+bier_bit_string_set_bit (bier_bit_string_t *bit_string,
+                         bier_bp_t bp)
+{
+    bier_bit_mask_bucket_t bmask;
+    uint16_t byte_pos, bit_pos;
+
+    BIER_BIT_POS_IS_VALID(bp, bit_string);
+    BIER_GET_STRING_POS(bp, byte_pos, bit_pos, bit_string);
+
+    bmask = ((bier_bit_mask_bucket_t)1 << bit_pos);
+    bit_string->bbs_buckets[byte_pos] |= bmask;
+}
+
+void
+bier_bit_string_clear_bit (bier_bit_string_t *bit_string,
+                           bier_bp_t bp)
+{
+    uint16_t byte_pos, bit_pos;
+
+    BIER_BIT_POS_IS_VALID(bp, bit_string);
+    BIER_GET_STRING_POS(bp, byte_pos, bit_pos, bit_string);
+
+    bit_string->bbs_buckets[byte_pos] &= ~(1 << bit_pos);
+}
+
+u8 *
+format_bier_bit_string (u8 * string,
+                        va_list * args)
+{
+    bier_bit_string_t *bs = va_arg(*args, bier_bit_string_t *);
+    int leading_marker = 0;
+    int suppress_zero = 0;
+    u16 index;
+    u32 *ptr;
+
+    ptr = (u32 *)bs->bbs_buckets;
+
+    string = format(string, "%d#", (8 * bs->bbs_len));
+
+    for (index = 0; index < (bs->bbs_len/4); index++) {
+        if (!ptr[index]) {
+            if (!leading_marker) {
+                leading_marker = 1;
+                suppress_zero = 1;
+                string = format(string, ":");
+                continue;
+            }
+            if (suppress_zero) continue;
+        } else {
+            suppress_zero = 0;
+        }
+
+        string = format(string, "%s%X", index ? ":" : "",
+                        clib_net_to_host_u32(ptr[index]));
+    }
+
+    return (string);
+}