[Emu] [ONOS-2601] Implement BGP Update protocol message and parse all basic path attributes.
Change-Id: I85f912eeebacf46d699fdcf5549e06bae702823e
diff --git a/bgp/bgpio/src/main/java/org/onosproject/bgpio/types/As4Path.java b/bgp/bgpio/src/main/java/org/onosproject/bgpio/types/As4Path.java
new file mode 100644
index 0000000..90e94e8
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+++ b/bgp/bgpio/src/main/java/org/onosproject/bgpio/types/As4Path.java
@@ -0,0 +1,170 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.bgpio.types;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.onosproject.bgpio.exceptions.BGPParseException;
+import org.onosproject.bgpio.util.Validation;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.base.MoreObjects;
+
+/**
+ * Provides Implementation of As4Path BGP Path Attribute.
+ */
+public class As4Path implements BGPValueType {
+ private static final Logger log = LoggerFactory.getLogger(AsPath.class);
+ public static final byte AS4PATH_TYPE = 17;
+ public static final byte ASNUM_SIZE = 4;
+ public static final int TYPE_AND_LEN_AS_SHORT = 4;
+ public static final int TYPE_AND_LEN_AS_BYTE = 3;
+
+ private List<Integer> as4pathSet;
+ private List<Integer> as4pathSeq;
+
+ /**
+ * Initialize fields.
+ */
+ public As4Path() {
+ this.as4pathSeq = null;
+ this.as4pathSet = null;
+ }
+
+ /**
+ * Constructor to initialize parameters.
+ *
+ * @param as4pathSet AS4path Set
+ * @param as4pathSeq AS4path Sequence
+ */
+ public As4Path(List<Integer> as4pathSet, List<Integer> as4pathSeq) {
+ this.as4pathSeq = as4pathSeq;
+ this.as4pathSet = as4pathSet;
+ }
+
+ /**
+ * Reads from the channel buffer and parses As4Path.
+ *
+ * @param cb ChannelBuffer
+ * @return object of As4Path
+ * @throws BGPParseException while parsing As4Path
+ */
+ public static As4Path read(ChannelBuffer cb) throws BGPParseException {
+ List<Integer> as4pathSet = new ArrayList<>();
+ List<Integer> as4pathSeq = new ArrayList<>();
+ ChannelBuffer tempCb = cb.copy();
+ Validation validation = Validation.parseAttributeHeader(cb);
+
+ if (cb.readableBytes() < validation.getLength()) {
+ Validation.validateLen(BGPErrorType.UPDATE_MESSAGE_ERROR, BGPErrorType.ATTRIBUTE_LENGTH_ERROR,
+ validation.getLength());
+ }
+ //if fourth bit is set length is read as short otherwise as byte , len includes type, length and value
+ int len = validation.isShort() ? validation.getLength() + TYPE_AND_LEN_AS_SHORT : validation
+ .getLength() + TYPE_AND_LEN_AS_BYTE;
+ ChannelBuffer data = tempCb.readBytes(len);
+ if (validation.getFirstBit() && !validation.getSecondBit() && validation.getThirdBit()) {
+ throw new BGPParseException(BGPErrorType.UPDATE_MESSAGE_ERROR, BGPErrorType.ATTRIBUTE_FLAGS_ERROR, data);
+ }
+
+ ChannelBuffer tempBuf = cb.readBytes(validation.getLength());
+ while (tempBuf.readableBytes() > 0) {
+ byte pathSegType = tempBuf.readByte();
+ //no of ASes
+ byte pathSegLen = tempBuf.readByte();
+ //length = no of Ases * ASnum size (4 bytes)
+ int length = pathSegLen * ASNUM_SIZE;
+ if (tempBuf.readableBytes() < length) {
+ Validation.validateLen(BGPErrorType.UPDATE_MESSAGE_ERROR,
+ BGPErrorType.ATTRIBUTE_LENGTH_ERROR, length);
+ }
+ ChannelBuffer aspathBuf = tempBuf.readBytes(length);
+ while (aspathBuf.readableBytes() > 0) {
+ int asNum;
+ asNum = aspathBuf.readInt();
+ switch (pathSegType) {
+ case AsPath.ASPATH_SET_TYPE:
+ as4pathSet.add(asNum);
+ break;
+ case AsPath.ASPATH_SEQ_TYPE:
+ as4pathSeq.add(asNum);
+ break;
+ default: log.debug("Other type Not Supported:" + pathSegType);
+ }
+ }
+ }
+ return new As4Path(as4pathSet, as4pathSeq);
+ }
+
+ @Override
+ public short getType() {
+ return AS4PATH_TYPE;
+ }
+
+ /**
+ * Returns list of ASNum in AS4path Sequence.
+ *
+ * @return list of ASNum in AS4path Sequence
+ */
+ public List<Integer> as4PathSEQ() {
+ return this.as4pathSeq;
+ }
+
+ /**
+ * Returns list of ASNum in AS4path Set.
+ *
+ * @return list of ASNum in AS4path Set
+ */
+ public List<Integer> as4PathSET() {
+ return this.as4pathSet;
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(as4pathSet, as4pathSeq);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (this == obj) {
+ return true;
+ }
+ if (obj instanceof As4Path) {
+ As4Path other = (As4Path) obj;
+ return Objects.equals(as4pathSet, other.as4pathSet) && Objects.equals(as4pathSeq, other.as4pathSeq);
+ }
+ return false;
+ }
+
+ @Override
+ public String toString() {
+ return MoreObjects.toStringHelper(getClass())
+ .omitNullValues()
+ .add("as4pathSet", as4pathSet)
+ .add("as4pathSeq", as4pathSeq)
+ .toString();
+ }
+
+ @Override
+ public int write(ChannelBuffer cb) {
+ //Not required to Implement as of now
+ return 0;
+ }
+}
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