summary refs log tree commit diff
path: root/crypto/src/asn1/DerEnumerated.cs
blob: 03d85fbfd14aeb18205288eb746980361e2767cf (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
using System;

using Org.BouncyCastle.Math;
using Org.BouncyCastle.Utilities;

namespace Org.BouncyCastle.Asn1
{
    public class DerEnumerated
        : Asn1Object
    {
        private readonly byte[] bytes;
        private readonly int start;

        /**
         * return an integer from the passed in object
         *
         * @exception ArgumentException if the object cannot be converted.
         */
        public static DerEnumerated GetInstance(
            object obj)
        {
            if (obj == null || obj is DerEnumerated)
            {
                return (DerEnumerated)obj;
            }

            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj));
        }

        /**
         * return an Enumerated from a tagged object.
         *
         * @param obj the tagged object holding the object we want
         * @param explicitly true if the object is meant to be explicitly
         *              tagged false otherwise.
         * @exception ArgumentException if the tagged object cannot
         *               be converted.
         */
        public static DerEnumerated GetInstance(
            Asn1TaggedObject	obj,
            bool				isExplicit)
        {
            Asn1Object o = obj.GetObject();

            if (isExplicit || o is DerEnumerated)
            {
                return GetInstance(o);
            }

            return FromOctetString(((Asn1OctetString)o).GetOctets());
        }

        public DerEnumerated(int val)
        {
            if (val < 0)
                throw new ArgumentException("enumerated must be non-negative", "val");

            this.bytes = BigInteger.ValueOf(val).ToByteArray();
            this.start = 0;
        }

        public DerEnumerated(long val)
        {
            if (val < 0L)
                throw new ArgumentException("enumerated must be non-negative", "val");

            this.bytes = BigInteger.ValueOf(val).ToByteArray();
            this.start = 0;
        }

        public DerEnumerated(BigInteger val)
        {
            if (val.SignValue < 0)
                throw new ArgumentException("enumerated must be non-negative", "val");

            this.bytes = val.ToByteArray();
            this.start = 0;
        }

        public DerEnumerated(byte[] bytes)
        {
            if (DerInteger.IsMalformed(bytes))
                throw new ArgumentException("malformed enumerated", "bytes");
            if (0 != (bytes[0] & 0x80))
                throw new ArgumentException("enumerated must be non-negative", "bytes");

            this.bytes = Arrays.Clone(bytes);
            this.start = DerInteger.SignBytesToSkip(bytes);
        }

        public BigInteger Value
        {
            get { return new BigInteger(bytes); }
        }

        public bool HasValue(int x)
        {
            return (bytes.Length - start) <= 4
                && DerInteger.IntValue(bytes, start, DerInteger.SignExtSigned) == x;
        }

        public bool HasValue(BigInteger x)
        {
            return null != x
                // Fast check to avoid allocation
                && DerInteger.IntValue(bytes, start, DerInteger.SignExtSigned) == x.IntValue
                && Value.Equals(x);
        }

        public int IntValueExact
        {
            get
            {
                int count = bytes.Length - start;
                if (count > 4)
                    throw new ArithmeticException("ASN.1 Enumerated out of int range");

                return DerInteger.IntValue(bytes, start, DerInteger.SignExtSigned);
            }
        }

        internal override bool EncodeConstructed()
        {
            return false;
        }

        internal override int EncodedLength(bool withID)
        {
            return Asn1OutputStream.GetLengthOfEncodingDL(withID, bytes.Length);
        }

        internal override void Encode(Asn1OutputStream asn1Out, bool withID)
        {
            asn1Out.WriteEncodingDL(withID, Asn1Tags.Enumerated, bytes);
        }

        protected override bool Asn1Equals(Asn1Object asn1Object)
        {
            DerEnumerated other = asn1Object as DerEnumerated;
            if (other == null)
                return false;

            return Arrays.AreEqual(this.bytes, other.bytes);
        }

        protected override int Asn1GetHashCode()
        {
            return Arrays.GetHashCode(bytes);
        }

        private static readonly DerEnumerated[] cache = new DerEnumerated[12];

        internal static DerEnumerated FromOctetString(byte[] enc)
        {
            if (enc.Length > 1)
                return new DerEnumerated(enc);
            if (enc.Length == 0)
                throw new ArgumentException("ENUMERATED has zero length", "enc");

            int value = enc[0];
            if (value >= cache.Length)
                return new DerEnumerated(enc);

            DerEnumerated possibleMatch = cache[value];
            if (possibleMatch == null)
            {
                cache[value] = possibleMatch = new DerEnumerated(enc);
            }
            return possibleMatch;
        }
    }
}