summary refs log tree commit diff
path: root/crypto/src/asn1/Asn1Set.cs
blob: 453627b7c465a75e48f3539c3acad04b318c5ce0 (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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
using System;
using System.Collections;
using System.Diagnostics;
using System.IO;

#if PORTABLE
using System.Collections.Generic;
using System.Linq;
#endif

using Org.BouncyCastle.Utilities;
using Org.BouncyCastle.Utilities.Collections;

namespace Org.BouncyCastle.Asn1
{
    abstract public class Asn1Set
        : Asn1Object, IEnumerable
    {
        // NOTE: Only non-readonly to support LazyDerSet
        internal Asn1Encodable[] elements;

        /**
         * return an ASN1Set from the given object.
         *
         * @param obj the object we want converted.
         * @exception ArgumentException if the object cannot be converted.
         */
        public static Asn1Set GetInstance(object obj)
        {
            if (obj == null || obj is Asn1Set)
            {
                return (Asn1Set)obj;
            }
            //else if (obj is Asn1SetParser)
            else if (obj is IAsn1Convertible)
            {
                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
                if (asn1Object is Asn1Set)
                    return (Asn1Set)asn1Object;
            }
            else if (obj is byte[])
            {
                try
                {
                    return GetInstance(FromByteArray((byte[])obj));
                }
                catch (IOException e)
                {
                    throw new ArgumentException("failed to construct set from byte[]: " + e.Message);
                }
            }

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

        /**
         * Return an ASN1 set from a tagged object. There is a special
         * case here, if an object appears to have been explicitly tagged on
         * reading but we were expecting it to be implicitly tagged in the
         * normal course of events it indicates that we lost the surrounding
         * set - so we need to add it back (this will happen if the tagged
         * object is a sequence that contains other sequences). If you are
         * dealing with implicitly tagged sets you really <b>should</b>
         * be using this method.
         *
         * @param obj the tagged object.
         * @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 Asn1Set GetInstance(
            Asn1TaggedObject	obj,
            bool				explicitly)
        {
            Asn1Object inner = obj.GetObject();

            if (explicitly)
            {
                if (!obj.IsExplicit())
                    throw new ArgumentException("object implicit - explicit expected.");

                return (Asn1Set) inner;
            }

            //
            // constructed object which appears to be explicitly tagged
            // and it's really implicit means we have to add the
            // surrounding sequence.
            //
            if (obj.IsExplicit())
            {
                return new DerSet(inner);
            }

            if (inner is Asn1Set)
            {
                return (Asn1Set) inner;
            }

            //
            // in this case the parser returns a sequence, convert it
            // into a set.
            //
            if (inner is Asn1Sequence)
            {
                Asn1EncodableVector v = new Asn1EncodableVector();
                Asn1Sequence s = (Asn1Sequence) inner;

                foreach (Asn1Encodable ae in s)
                {
                    v.Add(ae);
                }

                // TODO Should be able to construct set directly from sequence?
                return new DerSet(v, false);
            }

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

        protected internal Asn1Set()
        {
            this.elements = Asn1EncodableVector.EmptyElements;
        }

        protected internal Asn1Set(Asn1Encodable element)
        {
            if (null == element)
                throw new ArgumentNullException("element");

            this.elements = new Asn1Encodable[]{ element };
        }

        protected internal Asn1Set(params Asn1Encodable[] elements)
        {
            if (Arrays.IsNullOrContainsNull(elements))
                throw new NullReferenceException("'elements' cannot be null, or contain null");

            this.elements = Asn1EncodableVector.CloneElements(elements);
        }

        protected internal Asn1Set(Asn1EncodableVector elementVector)
        {
            if (null == elementVector)
                throw new ArgumentNullException("elementVector");

            this.elements = elementVector.TakeElements();
        }

        public virtual IEnumerator GetEnumerator()
        {
            return elements.GetEnumerator();
        }

        /**
         * return the object at the set position indicated by index.
         *
         * @param index the set number (starting at zero) of the object
         * @return the object at the set position indicated by index.
         */
        public virtual Asn1Encodable this[int index]
        {
            get { return elements[index]; }
        }

        public virtual int Count
        {
            get { return elements.Length; }
        }

        public virtual Asn1Encodable[] ToArray()
        {
            return Asn1EncodableVector.CloneElements(elements);
        }

        private class Asn1SetParserImpl
            : Asn1SetParser
        {
            private readonly Asn1Set outer;
            private readonly int max;
            private int index;

            public Asn1SetParserImpl(
                Asn1Set outer)
            {
                this.outer = outer;
                // NOTE: Call Count here to 'force' a LazyDerSet
                this.max = outer.Count;
            }

            public IAsn1Convertible ReadObject()
            {
                if (index == max)
                    return null;

                Asn1Encodable obj = outer[index++];
                if (obj is Asn1Sequence)
                    return ((Asn1Sequence)obj).Parser;

                if (obj is Asn1Set)
                    return ((Asn1Set)obj).Parser;

                // NB: Asn1OctetString implements Asn1OctetStringParser directly
//				if (obj is Asn1OctetString)
//					return ((Asn1OctetString)obj).Parser;

                return obj;
            }

            public virtual Asn1Object ToAsn1Object()
            {
                return outer;
            }
        }

        public Asn1SetParser Parser
        {
            get { return new Asn1SetParserImpl(this); }
        }

        protected override int Asn1GetHashCode()
        {
            // NOTE: Call Count here to 'force' a LazyDerSet
            int i = Count;
            int hc = i + 1;

            while (--i >= 0)
            {
                hc *= 257;
                hc ^= elements[i].ToAsn1Object().CallAsn1GetHashCode();
            }

            return hc;
        }

        protected override bool Asn1Equals(Asn1Object asn1Object)
        {
            Asn1Set that = asn1Object as Asn1Set;
            if (null == that)
                return false;

            // NOTE: Call Count here (on both) to 'force' a LazyDerSet
            int count = this.Count;
            if (that.Count != count)
                return false;

            for (int i = 0; i < count; ++i)
            {
                Asn1Object o1 = this.elements[i].ToAsn1Object();
                Asn1Object o2 = that.elements[i].ToAsn1Object();

                if (o1 != o2 && !o1.CallAsn1Equals(o2))
                    return false;
            }

            return true;
        }

        protected internal void Sort()
        {
            // NOTE: Call Count here to 'force' a LazyDerSet
            int count = Count;
            if (count < 2)
                return;

#if PORTABLE
            this.elements = elements
                .Cast<Asn1Encodable>()
                .Select(a => new { Item = a, Key = a.GetEncoded(Asn1Encodable.Der) })
                .OrderBy(t => t.Key, new DerComparer())
                .Select(t => t.Item)
                .ToArray();
#else
            byte[][] keys = new byte[count][];
            for (int i = 0; i < count; ++i)
            {
                keys[i] = elements[i].GetEncoded(Der);
            }
            Array.Sort(keys, elements, new DerComparer());
#endif
        }

        internal override bool EncodeConstructed()
        {
            return true;
        }

        public override string ToString()
        {
            return CollectionUtilities.ToString(elements);
        }

#if PORTABLE
        private class DerComparer
            : IComparer<byte[]>
        {
            public int Compare(byte[] x, byte[] y)
            {
                byte[] a = x, b = y;
#else
        private class DerComparer
            : IComparer
        {
            public int Compare(object x, object y)
            {
                byte[] a = (byte[])x, b = (byte[])y;
#endif
                Debug.Assert(a.Length >= 2 && b.Length >= 2);

                /*
                 * NOTE: Set elements in DER encodings are ordered first according to their tags (class and
                 * number); the CONSTRUCTED bit is not part of the tag.
                 * 
                 * For SET-OF, this is unimportant. All elements have the same tag and DER requires them to
                 * either all be in constructed form or all in primitive form, according to that tag. The
                 * elements are effectively ordered according to their content octets.
                 * 
                 * For SET, the elements will have distinct tags, and each will be in constructed or
                 * primitive form accordingly. Failing to ignore the CONSTRUCTED bit could therefore lead to
                 * ordering inversions.
                 */
                int a0 = a[0] & ~Asn1Tags.Constructed;
                int b0 = b[0] & ~Asn1Tags.Constructed;
                if (a0 != b0)
                    return a0 < b0 ? -1 : 1;

                int len = System.Math.Min(a.Length, b.Length);
                for (int i = 1; i < len; ++i)
                {
                    byte ai = a[i], bi = b[i];
                    if (ai != bi)
                        return ai < bi ? -1 : 1;
                }
                Debug.Assert(a.Length == b.Length);
                return 0;
            }
        }
    }
}