1 package org.metricshub.ipmi.core.coding.protocol.encoder;
2
3 /*-
4 * ╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲
5 * IPMI Java Client
6 * ჻჻჻჻჻჻
7 * Copyright 2023 Verax Systems, MetricsHub
8 * ჻჻჻჻჻჻
9 * This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as
11 * published by the Free Software Foundation, either version 3 of the
12 * License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Lesser Public License for more details.
18 *
19 * You should have received a copy of the GNU General Lesser Public
20 * License along with this program. If not, see
21 * <http://www.gnu.org/licenses/lgpl-3.0.html>.
22 * ╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱╲╱
23 */
24
25 import org.metricshub.ipmi.core.coding.protocol.AuthenticationType;
26 import org.metricshub.ipmi.core.common.TypeConverter;
27
28 /**
29 * Adds IPMI session header to encrypted payload. Should be used to encode
30 * regular RMCP+ messages (excluding Open Session and RAKP Messages)
31 */
32 public abstract class ProtocolEncoder implements IpmiEncoder {
33
34 protected byte encodeAuthenticationType(
35 AuthenticationType authenticationType) {
36 return TypeConverter.intToByte(authenticationType.getCode());
37 }
38
39 /**
40 * Converts integer value into byte array using little endian convention and
41 * inserts it into message at given offset.
42 *
43 * @param value
44 * @param message
45 * - IPMI message being created
46 * @param offset
47 * @throws IndexOutOfBoundsException
48 * when message is too short to hold value at given offset
49 */
50 protected void encodeInt(int value, byte[] message, int offset) {
51 byte[] array = TypeConverter.intToLittleEndianByteArray(value);
52
53 if (array.length + offset > message.length) {
54 throw new IndexOutOfBoundsException("Message is too short");
55 }
56
57 System.arraycopy(array, 0, message, offset, array.length);
58 }
59
60 /**
61 * Encodes session sequence number and inserts it into message at given
62 * offset.
63 *
64 * @param value
65 * @param message
66 * - IPMI message being created
67 * @param offset
68 * @throws IndexOutOfBoundsException
69 * when message is too short to hold value at given offset
70 */
71 protected void encodeSessionSequenceNumber(int value, byte[] message, int offset) {
72 encodeInt(value, message, offset);
73 }
74
75 /**
76 * Encodes session id and inserts it into message at given offset.
77 *
78 * @param value
79 * @param message
80 * - IPMI message being created
81 * @param offset
82 * @throws IndexOutOfBoundsException
83 * when message is too short to hold value at given offset
84 */
85 protected void encodeSessionId(int value, byte[] message, int offset) {
86 encodeInt(value, message, offset);
87 }
88
89 /**
90 * Encodes payload length and inserts it into message at given offset.
91 *
92 * @param value
93 * @param message
94 * - IPMI message being created
95 * @param offset
96 * @throws IndexOutOfBoundsException
97 * when message is too short to hold value at given offset
98 */
99 protected abstract void encodePayloadLength(int value, byte[] message, int offset);
100
101 /**
102 * Encodes payload and inserts it into message at given offset. <br>
103 * When payload == null it will not be inserted.
104 *
105 * @param payload
106 * - IPMI payload to encode.
107 * @param message
108 * - IPMI message being created.
109 * @param offset
110 * @throws IndexOutOfBoundsException
111 * when message is too short to hold value at given offset
112 * @return offset + encoded message length
113 */
114 protected int encodePayload(byte[] payload, byte[] message, int offset) {
115 if (payload == null) {
116 return offset;
117 }
118 if (payload.length + offset > message.length) {
119 throw new IndexOutOfBoundsException("Message is too short");
120 }
121 System.arraycopy(payload, 0, message, offset, payload.length);
122 return offset + payload.length;
123 }
124 }