online-dsl-forge 0.3.3

A bounded parser and runtime for in-memory DSL expressions.
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
135
136
137
138
139
140
141
142
143
144

use std::net::IpAddr;

use crate::rulepack_render::error::{RenderResult, fail};

pub(crate) fn validate_non_empty(source: &str, field: &str, value: &str) -> RenderResult<()> {
  if value.trim().is_empty() {
    return fail(format!("{source} {field} must not be empty"));
  }
  Ok(())
}

pub(crate) fn validate_label(source: &str, field: &str, value: &str) -> RenderResult<()> {
  validate_non_empty(source, field, value)?;
  if value.len() > 128 {
    return fail(format!("{source} {field} exceeds 128 bytes"));
  }
  if !value
    .bytes()
    .all(|byte| byte.is_ascii_alphanumeric() || matches!(byte, b'_' | b'-' | b'.' | b':'))
  {
    return fail(format!("{source} {field} contains unsupported characters"));
  }
  Ok(())
}

pub(crate) fn validate_human_text(source: &str, field: &str, value: &str) -> RenderResult<()> {
  validate_non_empty(source, field, value)?;
  if value.len() > 512 || value.bytes().any(|byte| byte.is_ascii_control()) {
    return fail(format!("{source} {field} must be 1 to 512 printable bytes"));
  }
  Ok(())
}

pub(crate) fn validate_source_text(source: &str, field: &str, value: &str) -> RenderResult<()> {
  validate_non_empty(source, field, value)?;
  if value.len() > 2048 {
    return fail(format!("{source} {field} exceeds 2048 bytes"));
  }
  Ok(())
}

pub(crate) fn validate_source_sha256(source: &str, field: &str, value: &str) -> RenderResult<()> {
  validate_non_empty(source, field, value)?;
  if value.len() != 64 || !value.bytes().all(|byte| byte.is_ascii_hexdigit()) {
    return fail(format!(
      "{source} {field} must be a 64-character hex SHA-256 digest"
    ));
  }
  Ok(())
}

pub(crate) fn validate_source_fingerprint(
  source: &str,
  field: &str,
  value: &str,
) -> RenderResult<()> {
  validate_non_empty(source, field, value)?;
  if !matches!(value.len(), 40 | 64) || !value.bytes().all(|byte| byte.is_ascii_hexdigit()) {
    return fail(format!(
      "{source} {field} must be a full 40- or 64-character hex OpenPGP fingerprint"
    ));
  }
  Ok(())
}

pub(crate) fn validate_cidr(value: &str) -> RenderResult<()> {
  let Some((address, prefix)) = value.split_once('/') else {
    return fail(format!("CIDR {value} must use address/prefix format"));
  };
  let address = address.parse::<IpAddr>().map_err(|_| {
    crate::rulepack_render::RulepackRenderError::new(format!("invalid CIDR {value}"))
  })?;
  let prefix = prefix.parse::<u8>().map_err(|_| {
    crate::rulepack_render::RulepackRenderError::new(format!("invalid CIDR prefix in {value}"))
  })?;
  let max_prefix = match address {
    IpAddr::V4(_) => 32,
    IpAddr::V6(_) => 128,
  };
  if prefix > max_prefix {
    return fail(format!("CIDR prefix in {value} exceeds {max_prefix}"));
  }
  Ok(())
}

pub(crate) fn validate_rate(value: &str) -> RenderResult<()> {
  let Some((amount, unit)) = value.split_once("r/") else {
    return fail("rate must use format like 10r/s or 600r/m");
  };
  let amount = amount
    .parse::<f64>()
    .map_err(|_| crate::rulepack_render::RulepackRenderError::new("invalid rate amount"))?;
  if !amount.is_finite() {
    return fail("rate amount must be finite");
  }
  if amount <= 0.0 {
    return fail("rate amount must be greater than 0");
  }
  if !matches!(unit, "s" | "m" | "h") {
    return fail("rate unit must be s, m, or h");
  }
  Ok(())
}

pub(crate) fn validate_status(source: &str, field: &str, status: u16) -> RenderResult<()> {
  if !(100..=599).contains(&status) {
    return fail(format!("{source} {field} {status} is invalid"));
  }
  Ok(())
}

pub(crate) fn validate_method(value: &str) -> RenderResult<()> {
  validate_token(value, "HTTP method")
}

fn validate_token(value: &str, label: &str) -> RenderResult<()> {
  if value.is_empty()
    || value.len() > 32
    || !value.bytes().all(|byte| {
      byte.is_ascii_alphanumeric()
        || matches!(
          byte,
          b'!'
            | b'#'
            | b'$'
            | b'%'
            | b'&'
            | b'\''
            | b'*'
            | b'+'
            | b'-'
            | b'.'
            | b'^'
            | b'_'
            | b'`'
            | b'|'
            | b'~'
        )
    })
  {
    return fail(format!("{label} must be a valid HTTP token"));
  }
  Ok(())
}