Don Newton | 379ae25 | 2019-04-01 12:17:06 -0400 | [diff] [blame^] | 1 | // Copyright (C) MongoDB, Inc. 2017-present. |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); you may |
| 4 | // not use this file except in compliance with the License. You may obtain |
| 5 | // a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 |
| 6 | |
| 7 | package auth |
| 8 | |
| 9 | import ( |
| 10 | "context" |
| 11 | |
| 12 | "github.com/mongodb/mongo-go-driver/bson" |
| 13 | "github.com/mongodb/mongo-go-driver/x/bsonx" |
| 14 | "github.com/mongodb/mongo-go-driver/x/network/command" |
| 15 | "github.com/mongodb/mongo-go-driver/x/network/description" |
| 16 | "github.com/mongodb/mongo-go-driver/x/network/wiremessage" |
| 17 | ) |
| 18 | |
| 19 | // SaslClient is the client piece of a sasl conversation. |
| 20 | type SaslClient interface { |
| 21 | Start() (string, []byte, error) |
| 22 | Next(challenge []byte) ([]byte, error) |
| 23 | Completed() bool |
| 24 | } |
| 25 | |
| 26 | // SaslClientCloser is a SaslClient that has resources to clean up. |
| 27 | type SaslClientCloser interface { |
| 28 | SaslClient |
| 29 | Close() |
| 30 | } |
| 31 | |
| 32 | // ConductSaslConversation handles running a sasl conversation with MongoDB. |
| 33 | func ConductSaslConversation(ctx context.Context, desc description.Server, rw wiremessage.ReadWriter, db string, client SaslClient) error { |
| 34 | // Arbiters cannot be authenticated |
| 35 | if desc.Kind == description.RSArbiter { |
| 36 | return nil |
| 37 | } |
| 38 | |
| 39 | if db == "" { |
| 40 | db = defaultAuthDB |
| 41 | } |
| 42 | |
| 43 | if closer, ok := client.(SaslClientCloser); ok { |
| 44 | defer closer.Close() |
| 45 | } |
| 46 | |
| 47 | mech, payload, err := client.Start() |
| 48 | if err != nil { |
| 49 | return newError(err, mech) |
| 50 | } |
| 51 | |
| 52 | saslStartCmd := command.Read{ |
| 53 | DB: db, |
| 54 | Command: bsonx.Doc{ |
| 55 | {"saslStart", bsonx.Int32(1)}, |
| 56 | {"mechanism", bsonx.String(mech)}, |
| 57 | {"payload", bsonx.Binary(0x00, payload)}, |
| 58 | }, |
| 59 | } |
| 60 | |
| 61 | type saslResponse struct { |
| 62 | ConversationID int `bson:"conversationId"` |
| 63 | Code int `bson:"code"` |
| 64 | Done bool `bson:"done"` |
| 65 | Payload []byte `bson:"payload"` |
| 66 | } |
| 67 | |
| 68 | var saslResp saslResponse |
| 69 | |
| 70 | ssdesc := description.SelectedServer{Server: desc} |
| 71 | rdr, err := saslStartCmd.RoundTrip(ctx, ssdesc, rw) |
| 72 | if err != nil { |
| 73 | return newError(err, mech) |
| 74 | } |
| 75 | |
| 76 | err = bson.Unmarshal(rdr, &saslResp) |
| 77 | if err != nil { |
| 78 | return newAuthError("unmarshall error", err) |
| 79 | } |
| 80 | |
| 81 | cid := saslResp.ConversationID |
| 82 | |
| 83 | for { |
| 84 | if saslResp.Code != 0 { |
| 85 | return newError(err, mech) |
| 86 | } |
| 87 | |
| 88 | if saslResp.Done && client.Completed() { |
| 89 | return nil |
| 90 | } |
| 91 | |
| 92 | payload, err = client.Next(saslResp.Payload) |
| 93 | if err != nil { |
| 94 | return newError(err, mech) |
| 95 | } |
| 96 | |
| 97 | if saslResp.Done && client.Completed() { |
| 98 | return nil |
| 99 | } |
| 100 | |
| 101 | saslContinueCmd := command.Read{ |
| 102 | DB: db, |
| 103 | Command: bsonx.Doc{ |
| 104 | {"saslContinue", bsonx.Int32(1)}, |
| 105 | {"conversationId", bsonx.Int32(int32(cid))}, |
| 106 | {"payload", bsonx.Binary(0x00, payload)}, |
| 107 | }, |
| 108 | } |
| 109 | |
| 110 | rdr, err = saslContinueCmd.RoundTrip(ctx, ssdesc, rw) |
| 111 | if err != nil { |
| 112 | return newError(err, mech) |
| 113 | } |
| 114 | |
| 115 | err = bson.Unmarshal(rdr, &saslResp) |
| 116 | if err != nil { |
| 117 | return newAuthError("unmarshal error", err) |
| 118 | } |
| 119 | } |
| 120 | } |