aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/csharp/Grpc.Core/CallCredentials.cs
blob: 7476b0ca165b0d3e2b3e5dccd9ed55d18ce3f6f9 (plain)
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
#region Copyright notice and license

// Copyright 2015, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#endregion

using System;
using System.Collections.Generic;
using System.Threading.Tasks;

using Grpc.Core.Internal;
using Grpc.Core.Utils;

namespace Grpc.Core
{
    /// <summary>
    /// Client-side call credentials. Provide authorization with per-call granularity.
    /// </summary>
    public abstract class CallCredentials
    {
        /// <summary>
        /// Composes multiple multiple <c>CallCredentials</c> objects into
        /// a single <c>CallCredentials</c> object.
        /// </summary>
        /// <param name="credentials">credentials to compose</param>
        /// <returns>The new <c>CompositeCallCredentials</c></returns>
        public static CallCredentials Compose(params CallCredentials[] credentials)
        {
            return new CompositeCallCredentials(credentials);
        }

        /// <summary>
        /// Creates a new instance of <c>CallCredentials</c> class from an
        /// interceptor that can attach metadata to outgoing calls.
        /// </summary>
        /// <param name="interceptor">authentication interceptor</param>
        public static CallCredentials FromInterceptor(AsyncAuthInterceptor interceptor)
        {
            return new MetadataCredentials(interceptor);
        }

        /// <summary>
        /// Creates native object for the credentials.
        /// </summary>
        /// <returns>The native credentials.</returns>
        internal abstract CallCredentialsSafeHandle ToNativeCredentials();
    }

    /// <summary>
    /// Client-side credentials that delegate metadata based auth to an interceptor.
    /// The interceptor is automatically invoked for each remote call that uses <c>MetadataCredentials.</c>
    /// </summary>
    internal sealed class MetadataCredentials : CallCredentials
    {
        readonly AsyncAuthInterceptor interceptor;

        /// <summary>
        /// Initializes a new instance of <c>MetadataCredentials</c> class.
        /// </summary>
        /// <param name="interceptor">authentication interceptor</param>
        public MetadataCredentials(AsyncAuthInterceptor interceptor)
        {
            this.interceptor = GrpcPreconditions.CheckNotNull(interceptor);
        }

        internal override CallCredentialsSafeHandle ToNativeCredentials()
        {
            NativeMetadataCredentialsPlugin plugin = new NativeMetadataCredentialsPlugin(interceptor);
            return plugin.Credentials;
        }
    }

    /// <summary>
    /// Credentials that allow composing multiple credentials objects into one <see cref="CallCredentials"/> object.
    /// </summary>
    internal sealed class CompositeCallCredentials : CallCredentials
    {
        readonly List<CallCredentials> credentials;

        /// <summary>
        /// Initializes a new instance of <c>CompositeCallCredentials</c> class.
        /// The resulting credentials object will be composite of all the credentials specified as parameters.
        /// </summary>
        /// <param name="credentials">credentials to compose</param>
        public CompositeCallCredentials(params CallCredentials[] credentials)
        {
            GrpcPreconditions.CheckArgument(credentials.Length >= 2, "Composite credentials object can only be created from 2 or more credentials.");
            this.credentials = new List<CallCredentials>(credentials);
        }

        internal override CallCredentialsSafeHandle ToNativeCredentials()
        {
            return ToNativeRecursive(0);
        }

        // Recursive descent makes managing lifetime of intermediate CredentialSafeHandle instances easier.
        // In practice, we won't usually see composites from more than two credentials anyway.
        private CallCredentialsSafeHandle ToNativeRecursive(int startIndex)
        {
            if (startIndex == credentials.Count - 1)
            {
                return credentials[startIndex].ToNativeCredentials();
            }

            using (var cred1 = credentials[startIndex].ToNativeCredentials())
            using (var cred2 = ToNativeRecursive(startIndex + 1))
            {
                var nativeComposite = CallCredentialsSafeHandle.CreateComposite(cred1, cred2);
                if (nativeComposite.IsInvalid)
                {
                    throw new ArgumentException("Error creating native composite credentials. Likely, this is because you are trying to compose incompatible credentials.");
                }
                return nativeComposite;
            }
        }
    }
}