logo
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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183

//! ASN.1 `PrintableString` support.

use crate::{
    asn1::Any, ByteSlice, DecodeValue, Decoder, EncodeValue, Encoder, Error, FixedTag, Length,
    OrdIsValueOrd, Result, StrSlice, Tag,
};
use core::{fmt, str};

/// ASN.1 `PrintableString` type.
///
/// Supports a subset the ASCII character set (desribed below).
///
/// For UTF-8, use [`Utf8String`][`crate::asn1::Utf8String`] instead. For the
/// full ASCII character set, use [`Ia5String`][`crate::asn1::Ia5String`].
///
/// # Supported characters
///
/// The following ASCII characters/ranges are supported:
///
/// - `A..Z`
/// - `a..z`
/// - `0..9`
/// - "` `" (i.e. space)
/// - `\`
/// - `(`
/// - `)`
/// - `+`
/// - `,`
/// - `-`
/// - `.`
/// - `/`
/// - `:`
/// - `=`
/// - `?`
#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord)]
pub struct PrintableString<'a> {
    /// Inner value
    inner: StrSlice<'a>,
}

impl<'a> PrintableString<'a> {
    /// Create a new ASN.1 `PrintableString`.
    pub fn new<T>(input: &'a T) -> Result<Self>
    where
        T: AsRef<[u8]> + ?Sized,
    {
        let input = input.as_ref();

        // Validate all characters are within PrintedString's allowed set
        for &c in input.iter() {
            match c {
                b'A'..=b'Z'
                | b'a'..=b'z'
                | b'0'..=b'9'
                | b' '
                | b'\''
                | b'('
                | b')'
                | b'+'
                | b','
                | b'-'
                | b'.'
                | b'/'
                | b':'
                | b'='
                | b'?' => (),
                _ => return Err(Self::TAG.value_error()),
            }
        }

        StrSlice::from_bytes(input)
            .map(|inner| Self { inner })
            .map_err(|_| Self::TAG.value_error())
    }

    /// Borrow the string as a `str`.
    pub fn as_str(&self) -> &'a str {
        self.inner.as_str()
    }

    /// Borrow the string as bytes.
    pub fn as_bytes(&self) -> &'a [u8] {
        self.inner.as_bytes()
    }

    /// Get the length of the inner byte slice.
    pub fn len(&self) -> Length {
        self.inner.len()
    }

    /// Is the inner string empty?
    pub fn is_empty(&self) -> bool {
        self.inner.is_empty()
    }
}

impl AsRef<str> for PrintableString<'_> {
    fn as_ref(&self) -> &str {
        self.as_str()
    }
}

impl AsRef<[u8]> for PrintableString<'_> {
    fn as_ref(&self) -> &[u8] {
        self.as_bytes()
    }
}

impl<'a> DecodeValue<'a> for PrintableString<'a> {
    fn decode_value(decoder: &mut Decoder<'a>, length: Length) -> Result<Self> {
        Self::new(ByteSlice::decode_value(decoder, length)?.as_bytes())
    }
}

impl<'a> EncodeValue for PrintableString<'a> {
    fn value_len(&self) -> Result<Length> {
        self.inner.value_len()
    }

    fn encode_value(&self, encoder: &mut Encoder<'_>) -> Result<()> {
        self.inner.encode_value(encoder)
    }
}

impl FixedTag for PrintableString<'_> {
    const TAG: Tag = Tag::PrintableString;
}

impl OrdIsValueOrd for PrintableString<'_> {}

impl<'a> From<&PrintableString<'a>> for PrintableString<'a> {
    fn from(value: &PrintableString<'a>) -> PrintableString<'a> {
        *value
    }
}

impl<'a> TryFrom<Any<'a>> for PrintableString<'a> {
    type Error = Error;

    fn try_from(any: Any<'a>) -> Result<PrintableString<'a>> {
        any.decode_into()
    }
}

impl<'a> From<PrintableString<'a>> for Any<'a> {
    fn from(printable_string: PrintableString<'a>) -> Any<'a> {
        Any::from_tag_and_value(Tag::PrintableString, printable_string.inner.into())
    }
}

impl<'a> From<PrintableString<'a>> for &'a [u8] {
    fn from(printable_string: PrintableString<'a>) -> &'a [u8] {
        printable_string.as_bytes()
    }
}

impl<'a> fmt::Display for PrintableString<'a> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_str(self.as_str())
    }
}

impl<'a> fmt::Debug for PrintableString<'a> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "PrintableString({:?})", self.as_str())
    }
}

#[cfg(test)]
mod tests {
    use super::PrintableString;
    use crate::Decodable;

    #[test]
    fn parse_bytes() {
        let example_bytes = &[
            0x13, 0x0b, 0x54, 0x65, 0x73, 0x74, 0x20, 0x55, 0x73, 0x65, 0x72, 0x20, 0x31,
        ];

        let printable_string = PrintableString::from_der(example_bytes).unwrap();
        assert_eq!(printable_string.as_str(), "Test User 1");
    }
}