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

use crate::{
    bson::{doc, spec::BinarySubtype, Binary, Bson, Document},
    bson_util,
    client::{auth::AuthMechanism, options::ServerApi},
    cmap::Command,
    error::{Error, Result},
    operation::{CommandErrorBody, CommandResponse},
};

/// Encapsulates the command building of a `saslStart` command.
pub(super) struct SaslStart {
    source: String,
    mechanism: AuthMechanism,
    payload: Vec<u8>,
    server_api: Option<ServerApi>,
}

impl SaslStart {
    pub(super) fn new(
        source: String,
        mechanism: AuthMechanism,
        payload: Vec<u8>,
        server_api: Option<ServerApi>,
    ) -> Self {
        Self {
            source,
            mechanism,
            payload,
            server_api,
        }
    }

    pub(super) fn into_command(self) -> Command {
        let mut body = doc! {
            "saslStart": 1,
            "mechanism": self.mechanism.as_str(),
            "payload": Binary { subtype: BinarySubtype::Generic, bytes: self.payload },
        };
        if self.mechanism == AuthMechanism::ScramSha1
            || self.mechanism == AuthMechanism::ScramSha256
        {
            body.insert("options", doc! { "skipEmptyExchange": true });
        }

        let mut command = Command::new("saslStart".into(), self.source, body);
        if let Some(server_api) = self.server_api {
            command.set_server_api(&server_api);
        }

        command
    }
}

/// Encapsulates the command building of a `saslContinue` command.
pub(super) struct SaslContinue {
    source: String,
    conversation_id: Bson,
    payload: Vec<u8>,
    server_api: Option<ServerApi>,
}

impl SaslContinue {
    pub(super) fn new(
        source: String,
        conversation_id: Bson,
        payload: Vec<u8>,
        server_api: Option<ServerApi>,
    ) -> Self {
        Self {
            source,
            conversation_id,
            payload,
            server_api,
        }
    }

    pub(super) fn into_command(self) -> Command {
        let body = doc! {
            "saslContinue": 1,
            "conversationId": self.conversation_id,
            "payload": Binary { subtype: BinarySubtype::Generic, bytes: self.payload },
        };

        let mut command = Command::new("saslContinue".into(), self.source, body);
        if let Some(server_api) = self.server_api {
            command.set_server_api(&server_api);
        }

        command
    }
}

/// Validates that a `saslStart` or `saslContinue` command response is successful.
fn validate_command_success(auth_mechanism: &str, response: &Document) -> Result<()> {
    let ok = match response.get("ok") {
        Some(ok) => ok,
        None => return Ok(()),
    };

    match bson_util::get_int(ok) {
        Some(1) => Ok(()),
        Some(_) => {
            let source = bson::from_bson::<CommandResponse<CommandErrorBody>>(Bson::Document(
                response.clone(),
            ))
            .map(|cmd_resp| cmd_resp.body.into())
            .ok();
            Err(Error::authentication_error(
                auth_mechanism,
                response
                    .get_str("errmsg")
                    .unwrap_or("Authentication failure"),
            )
            .with_source(source))
        }
        _ => Err(Error::invalid_authentication_response(auth_mechanism)),
    }
}

/// Encapsulates the parsing of the response to a `saslStart` or `saslContinue` command.
#[derive(Debug)]
pub(super) struct SaslResponse {
    pub(super) conversation_id: Bson,
    pub(super) done: bool,
    pub(super) payload: Vec<u8>,
}

impl SaslResponse {
    pub(super) fn parse(auth_mechanism: &str, mut response: Document) -> Result<Self> {
        validate_command_success(auth_mechanism, &response)?;

        let conversation_id = response
            .remove("conversationId")
            .ok_or_else(|| Error::invalid_authentication_response(auth_mechanism))?;
        let done = response
            .remove("done")
            .and_then(|b| b.as_bool())
            .ok_or_else(|| Error::invalid_authentication_response(auth_mechanism))?;
        let payload = response
            .get_binary_generic_mut("payload")
            .map_err(|_| Error::invalid_authentication_response(auth_mechanism))?
            .drain(..)
            .collect();

        Ok(SaslResponse {
            conversation_id,
            done,
            payload,
        })
    }
}