tf-types 0.1.3

Core semantic types, traits, and schemas powering the TrustForge protocol.
Documentation 
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

//! SPIFFE bridge. Mirrors `tools/tf-types-ts/src/core/bridge-spiffe.ts`.

use crate::bridges::{Bridge, BridgeError, BridgeKind};

/// DNS-like label check, equivalent to the anchored pattern
/// `[A-Za-z0-9](?:[A-Za-z0-9.-]*[A-Za-z0-9])?`: alphanumeric first and
/// last byte, alphanumeric / `.` / `-` in between.
fn is_dns_like(s: &str) -> bool {
    let bytes = s.as_bytes();
    let Some((&first, rest)) = bytes.split_first() else {
        return false;
    };
    if !first.is_ascii_alphanumeric() {
        return false;
    }
    let Some((&last, middle)) = rest.split_last() else {
        return true; // single character
    };
    last.is_ascii_alphanumeric()
        && middle
            .iter()
            .all(|&b| b.is_ascii_alphanumeric() || b == b'.' || b == b'-')
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct ParsedSpiffeId {
    pub trust_domain: String,
    pub path: String,
    pub raw: String,
}

pub fn parse_spiffe_id(id: &str) -> Result<ParsedSpiffeId, BridgeError> {
    if id.is_empty() {
        return Err(BridgeError::InvalidInput("empty SPIFFE ID".into()));
    }
    let rest = id.strip_prefix("spiffe://").ok_or_else(|| {
        BridgeError::InvalidInput(format!("SPIFFE ID must start with spiffe://, got {:?}", id))
    })?;
    let (trust_domain, path) = match rest.find('/') {
        Some(i) => (&rest[..i], &rest[i + 1..]),
        None => (rest, ""),
    };
    if trust_domain.is_empty() {
        return Err(BridgeError::InvalidInput(
            "SPIFFE ID has no trust domain".into(),
        ));
    }
    if path.is_empty() {
        return Err(BridgeError::InvalidInput("SPIFFE ID has no path".into()));
    }
    if !is_dns_like(trust_domain) {
        return Err(BridgeError::InvalidInput(format!(
            "SPIFFE trust domain is not DNS-like: {}",
            trust_domain
        )));
    }
    Ok(ParsedSpiffeId {
        trust_domain: trust_domain.to_owned(),
        path: path.to_owned(),
        raw: id.to_owned(),
    })
}

pub fn spiffe_to_actor_id(id: &str) -> Result<String, BridgeError> {
    let parsed = parse_spiffe_id(id)?;
    Ok(format!(
        "tf:actor:service:{}/{}",
        parsed.trust_domain, parsed.path
    ))
}

pub fn actor_id_to_spiffe(actor_id: &str) -> Result<String, BridgeError> {
    // Shape: `tf:actor:<type>:<path>` where <type> has no `:` and <path>
    // is non-empty (may itself contain `:`).
    let malformed =
        || BridgeError::InvalidInput(format!("malformed actor URI: {}", actor_id));
    let rest = actor_id.strip_prefix("tf:actor:").ok_or_else(malformed)?;
    let colon = rest.find(':').ok_or_else(malformed)?;
    let (type_segment, path_segment) = (&rest[..colon], &rest[colon + 1..]);
    // `path` may contain further `:` but not a newline (parity with the
    // former `(.+)$` pattern, where `.` excluded `\n`).
    if type_segment.is_empty() || path_segment.is_empty() || path_segment.contains('\n') {
        return Err(malformed());
    }
    if type_segment != "service" {
        return Err(BridgeError::Unsupported(format!(
            "SPIFFE bridge only projects service actors, got {}",
            type_segment
        )));
    }
    let slash = path_segment.find('/').ok_or_else(|| {
        BridgeError::InvalidInput(format!(
            "service actor path must be <trust-domain>/<path>, got {}",
            path_segment
        ))
    })?;
    let trust_domain = &path_segment[..slash];
    let tail = &path_segment[slash + 1..];
    Ok(format!("spiffe://{}/{}", trust_domain, tail))
}

pub struct SpiffeBridge {
    pub bridge_id: String,
    pub trust_domain: String,
}

impl SpiffeBridge {
    pub fn new(bridge_id: impl Into<String>, trust_domain: impl Into<String>) -> Self {
        SpiffeBridge {
            bridge_id: bridge_id.into(),
            trust_domain: trust_domain.into(),
        }
    }

    pub fn to_actor_id(&self, id: &str) -> Result<String, BridgeError> {
        spiffe_to_actor_id(id)
    }

    pub fn to_spiffe(&self, actor_id: &str) -> Result<String, BridgeError> {
        actor_id_to_spiffe(actor_id)
    }
}

impl Bridge for SpiffeBridge {
    fn bridge_id(&self) -> &str {
        &self.bridge_id
    }
    fn kind(&self) -> BridgeKind {
        BridgeKind::Spiffe
    }
    fn trust_domain(&self) -> &str {
        &self.trust_domain
    }
}