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(AuthenticationType authenticationType) {
35 return TypeConverter.intToByte(authenticationType.getCode());
36 }
37
38 /**
39 * Converts integer value into byte array using little endian convention and
40 * inserts it into message at given offset.
41 *
42 * @param value
43 * @param message
44 * - IPMI message being created
45 * @param offset
46 * @throws IndexOutOfBoundsException
47 * when message is too short to hold value at given offset
48 */
49 protected void encodeInt(int value, byte[] message, int offset) {
50 byte[] array = TypeConverter.intToLittleEndianByteArray(value);
51
52 if (array.length + offset > message.length) {
53 throw new IndexOutOfBoundsException("Message is too short");
54 }
55
56 System.arraycopy(array, 0, message, offset, array.length);
57 }
58
59 /**
60 * Encodes session sequence number and inserts it into message at given
61 * offset.
62 *
63 * @param value
64 * @param message
65 * - IPMI message being created
66 * @param offset
67 * @throws IndexOutOfBoundsException
68 * when message is too short to hold value at given offset
69 */
70 protected void encodeSessionSequenceNumber(int value, byte[] message, int offset) {
71 encodeInt(value, message, offset);
72 }
73
74 /**
75 * Encodes session id and inserts it into message at given offset.
76 *
77 * @param value
78 * @param message
79 * - IPMI message being created
80 * @param offset
81 * @throws IndexOutOfBoundsException
82 * when message is too short to hold value at given offset
83 */
84 protected void encodeSessionId(int value, byte[] message, int offset) {
85 encodeInt(value, message, offset);
86 }
87
88 /**
89 * Encodes payload length and inserts it into message at given offset.
90 *
91 * @param value
92 * @param message
93 * - IPMI message being created
94 * @param offset
95 * @throws IndexOutOfBoundsException
96 * when message is too short to hold value at given offset
97 */
98 protected abstract void encodePayloadLength(int value, byte[] message, int offset);
99
100 /**
101 * Encodes payload and inserts it into message at given offset. <br>
102 * When payload == null it will not be inserted.
103 *
104 * @param payload
105 * - IPMI payload to encode.
106 * @param message
107 * - IPMI message being created.
108 * @param offset
109 * @throws IndexOutOfBoundsException
110 * when message is too short to hold value at given offset
111 * @return offset + encoded message length
112 */
113 protected int encodePayload(byte[] payload, byte[] message, int offset) {
114 if (payload == null) {
115 return offset;
116 }
117 if (payload.length + offset > message.length) {
118 throw new IndexOutOfBoundsException("Message is too short");
119 }
120 System.arraycopy(payload, 0, message, offset, payload.length);
121 return offset + payload.length;
122 }
123 }