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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
//! Various http headers
// This is mostly copy of [hyper](https://github.com/hyperium/hyper/tree/master/src/header)

use std::fmt;
use std::str::FromStr;

use bytes::{Bytes, BytesMut};
use mime::Mime;
use modhttp::header::GetAll;
use modhttp::Error as HttpError;
use percent_encoding;

pub use modhttp::header::*;

use error::ParseError;
use httpmessage::HttpMessage;

mod common;
mod shared;
#[doc(hidden)]
pub use self::common::*;
#[doc(hidden)]
pub use self::shared::*;

#[doc(hidden)]
/// A trait for any object that will represent a header field and value.
pub trait Header
where
    Self: IntoHeaderValue,
{
    /// Returns the name of the header field
    fn name() -> HeaderName;

    /// Parse a header
    fn parse<T: HttpMessage>(msg: &T) -> Result<Self, ParseError>;
}

#[doc(hidden)]
/// A trait for any object that can be Converted to a `HeaderValue`
pub trait IntoHeaderValue: Sized {
    /// The type returned in the event of a conversion error.
    type Error: Into<HttpError>;

    /// Try to convert value to a Header value.
    fn try_into(self) -> Result<HeaderValue, Self::Error>;
}

impl IntoHeaderValue for HeaderValue {
    type Error = InvalidHeaderValue;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        Ok(self)
    }
}

impl<'a> IntoHeaderValue for &'a str {
    type Error = InvalidHeaderValue;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        self.parse()
    }
}

impl<'a> IntoHeaderValue for &'a [u8] {
    type Error = InvalidHeaderValue;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        HeaderValue::from_bytes(self)
    }
}

impl IntoHeaderValue for Bytes {
    type Error = InvalidHeaderValueBytes;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        HeaderValue::from_shared(self)
    }
}

impl IntoHeaderValue for Vec<u8> {
    type Error = InvalidHeaderValueBytes;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        HeaderValue::from_shared(Bytes::from(self))
    }
}

impl IntoHeaderValue for String {
    type Error = InvalidHeaderValueBytes;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        HeaderValue::from_shared(Bytes::from(self))
    }
}

impl IntoHeaderValue for Mime {
    type Error = InvalidHeaderValueBytes;

    #[inline]
    fn try_into(self) -> Result<HeaderValue, Self::Error> {
        HeaderValue::from_shared(Bytes::from(format!("{}", self)))
    }
}

/// Represents supported types of content encodings
#[derive(Copy, Clone, PartialEq, Debug)]
pub enum ContentEncoding {
    /// Automatically select encoding based on encoding negotiation
    Auto,
    /// A format using the Brotli algorithm
    #[cfg(feature = "brotli")]
    Br,
    /// A format using the zlib structure with deflate algorithm
    #[cfg(feature = "flate2")]
    Deflate,
    /// Gzip algorithm
    #[cfg(feature = "flate2")]
    Gzip,
    /// Indicates the identity function (i.e. no compression, nor modification)
    Identity,
}

impl ContentEncoding {
    #[inline]
    /// Is the content compressed?
    pub fn is_compression(self) -> bool {
        match self {
            ContentEncoding::Identity | ContentEncoding::Auto => false,
            _ => true,
        }
    }

    #[inline]
    /// Convert content encoding to string
    pub fn as_str(self) -> &'static str {
        match self {
            #[cfg(feature = "brotli")]
            ContentEncoding::Br => "br",
            #[cfg(feature = "flate2")]
            ContentEncoding::Gzip => "gzip",
            #[cfg(feature = "flate2")]
            ContentEncoding::Deflate => "deflate",
            ContentEncoding::Identity | ContentEncoding::Auto => "identity",
        }
    }

    #[inline]
    /// default quality value
    pub fn quality(self) -> f64 {
        match self {
            #[cfg(feature = "brotli")]
            ContentEncoding::Br => 1.1,
            #[cfg(feature = "flate2")]
            ContentEncoding::Gzip => 1.0,
            #[cfg(feature = "flate2")]
            ContentEncoding::Deflate => 0.9,
            ContentEncoding::Identity | ContentEncoding::Auto => 0.1,
        }
    }
}

// TODO: remove memory allocation
impl<'a> From<&'a str> for ContentEncoding {
    fn from(s: &'a str) -> ContentEncoding {
        match AsRef::<str>::as_ref(&s.trim().to_lowercase()) {
            #[cfg(feature = "brotli")]
            "br" => ContentEncoding::Br,
            #[cfg(feature = "flate2")]
            "gzip" => ContentEncoding::Gzip,
            #[cfg(feature = "flate2")]
            "deflate" => ContentEncoding::Deflate,
            _ => ContentEncoding::Identity,
        }
    }
}

#[doc(hidden)]
pub(crate) struct Writer {
    buf: BytesMut,
}

impl Writer {
    fn new() -> Writer {
        Writer {
            buf: BytesMut::new(),
        }
    }
    fn take(&mut self) -> Bytes {
        self.buf.take().freeze()
    }
}

impl fmt::Write for Writer {
    #[inline]
    fn write_str(&mut self, s: &str) -> fmt::Result {
        self.buf.extend_from_slice(s.as_bytes());
        Ok(())
    }

    #[inline]
    fn write_fmt(&mut self, args: fmt::Arguments) -> fmt::Result {
        fmt::write(self, args)
    }
}

#[inline]
#[doc(hidden)]
/// Reads a comma-delimited raw header into a Vec.
pub fn from_comma_delimited<T: FromStr>(
    all: GetAll<HeaderValue>,
) -> Result<Vec<T>, ParseError> {
    let mut result = Vec::new();
    for h in all {
        let s = h.to_str().map_err(|_| ParseError::Header)?;
        result.extend(
            s.split(',')
                .filter_map(|x| match x.trim() {
                    "" => None,
                    y => Some(y),
                })
                .filter_map(|x| x.trim().parse().ok()),
        )
    }
    Ok(result)
}

#[inline]
#[doc(hidden)]
/// Reads a single string when parsing a header.
pub fn from_one_raw_str<T: FromStr>(val: Option<&HeaderValue>) -> Result<T, ParseError> {
    if let Some(line) = val {
        let line = line.to_str().map_err(|_| ParseError::Header)?;
        if !line.is_empty() {
            return T::from_str(line).or(Err(ParseError::Header));
        }
    }
    Err(ParseError::Header)
}

#[inline]
#[doc(hidden)]
/// Format an array into a comma-delimited string.
pub fn fmt_comma_delimited<T>(f: &mut fmt::Formatter, parts: &[T]) -> fmt::Result
where
    T: fmt::Display,
{
    let mut iter = parts.iter();
    if let Some(part) = iter.next() {
        fmt::Display::fmt(part, f)?;
    }
    for part in iter {
        f.write_str(", ")?;
        fmt::Display::fmt(part, f)?;
    }
    Ok(())
}

// From hyper v0.11.27 src/header/parsing.rs

/// An extended header parameter value (i.e., tagged with a character set and optionally,
/// a language), as defined in [RFC 5987](https://tools.ietf.org/html/rfc5987#section-3.2).
#[derive(Clone, Debug, PartialEq)]
pub struct ExtendedValue {
    /// The character set that is used to encode the `value` to a string.
    pub charset: Charset,
    /// The human language details of the `value`, if available.
    pub language_tag: Option<LanguageTag>,
    /// The parameter value, as expressed in octets.
    pub value: Vec<u8>,
}

/// Parses extended header parameter values (`ext-value`), as defined in
/// [RFC 5987](https://tools.ietf.org/html/rfc5987#section-3.2).
///
/// Extended values are denoted by parameter names that end with `*`.
///
/// ## ABNF
///
/// ```text
/// ext-value     = charset  "'" [ language ] "'" value-chars
///               ; like RFC 2231's <extended-initial-value>
///               ; (see [RFC2231], Section 7)
///
/// charset       = "UTF-8" / "ISO-8859-1" / mime-charset
///
/// mime-charset  = 1*mime-charsetc
/// mime-charsetc = ALPHA / DIGIT
///               / "!" / "#" / "$" / "%" / "&"
///               / "+" / "-" / "^" / "_" / "`"
///               / "{" / "}" / "~"
///               ; as <mime-charset> in Section 2.3 of [RFC2978]
///               ; except that the single quote is not included
///               ; SHOULD be registered in the IANA charset registry
///
/// language      = <Language-Tag, defined in [RFC5646], Section 2.1>
///
/// value-chars   = *( pct-encoded / attr-char )
///
/// pct-encoded   = "%" HEXDIG HEXDIG
///               ; see [RFC3986], Section 2.1
///
/// attr-char     = ALPHA / DIGIT
///               / "!" / "#" / "$" / "&" / "+" / "-" / "."
///               / "^" / "_" / "`" / "|" / "~"
///               ; token except ( "*" / "'" / "%" )
/// ```
pub fn parse_extended_value(val: &str) -> Result<ExtendedValue, ::error::ParseError> {
    // Break into three pieces separated by the single-quote character
    let mut parts = val.splitn(3, '\'');

    // Interpret the first piece as a Charset
    let charset: Charset = match parts.next() {
        None => return Err(::error::ParseError::Header),
        Some(n) => FromStr::from_str(n).map_err(|_| ::error::ParseError::Header)?,
    };

    // Interpret the second piece as a language tag
    let language_tag: Option<LanguageTag> = match parts.next() {
        None => return Err(::error::ParseError::Header),
        Some("") => None,
        Some(s) => match s.parse() {
            Ok(lt) => Some(lt),
            Err(_) => return Err(::error::ParseError::Header),
        },
    };

    // Interpret the third piece as a sequence of value characters
    let value: Vec<u8> = match parts.next() {
        None => return Err(::error::ParseError::Header),
        Some(v) => percent_encoding::percent_decode(v.as_bytes()).collect(),
    };

    Ok(ExtendedValue {
        value,
        charset,
        language_tag,
    })
}

impl fmt::Display for ExtendedValue {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        let encoded_value = percent_encoding::percent_encode(
            &self.value[..],
            self::percent_encoding_http::HTTP_VALUE,
        );
        if let Some(ref lang) = self.language_tag {
            write!(f, "{}'{}'{}", self.charset, lang, encoded_value)
        } else {
            write!(f, "{}''{}", self.charset, encoded_value)
        }
    }
}

/// Percent encode a sequence of bytes with a character set defined in
/// [https://tools.ietf.org/html/rfc5987#section-3.2][url]
///
/// [url]: https://tools.ietf.org/html/rfc5987#section-3.2
pub fn http_percent_encode(f: &mut fmt::Formatter, bytes: &[u8]) -> fmt::Result {
    let encoded =
        percent_encoding::percent_encode(bytes, self::percent_encoding_http::HTTP_VALUE);
    fmt::Display::fmt(&encoded, f)
}
mod percent_encoding_http {
    use percent_encoding;

    // internal module because macro is hard-coded to make a public item
    // but we don't want to public export this item
    define_encode_set! {
        // This encode set is used for HTTP header values and is defined at
        // https://tools.ietf.org/html/rfc5987#section-3.2
        pub HTTP_VALUE = [percent_encoding::SIMPLE_ENCODE_SET] | {
            ' ', '"', '%', '\'', '(', ')', '*', ',', '/', ':', ';', '<', '-', '>', '?',
            '[', '\\', ']', '{', '}'
        }
    }
}

#[cfg(test)]
mod tests {
    use super::{parse_extended_value, ExtendedValue};
    use header::shared::Charset;
    use language_tags::LanguageTag;

    #[test]
    fn test_parse_extended_value_with_encoding_and_language_tag() {
        let expected_language_tag = "en".parse::<LanguageTag>().unwrap();
        // RFC 5987, Section 3.2.2
        // Extended notation, using the Unicode character U+00A3 (POUND SIGN)
        let result = parse_extended_value("iso-8859-1'en'%A3%20rates");
        assert!(result.is_ok());
        let extended_value = result.unwrap();
        assert_eq!(Charset::Iso_8859_1, extended_value.charset);
        assert!(extended_value.language_tag.is_some());
        assert_eq!(expected_language_tag, extended_value.language_tag.unwrap());
        assert_eq!(
            vec![163, b' ', b'r', b'a', b't', b'e', b's'],
            extended_value.value
        );
    }

    #[test]
    fn test_parse_extended_value_with_encoding() {
        // RFC 5987, Section 3.2.2
        // Extended notation, using the Unicode characters U+00A3 (POUND SIGN)
        // and U+20AC (EURO SIGN)
        let result = parse_extended_value("UTF-8''%c2%a3%20and%20%e2%82%ac%20rates");
        assert!(result.is_ok());
        let extended_value = result.unwrap();
        assert_eq!(Charset::Ext("UTF-8".to_string()), extended_value.charset);
        assert!(extended_value.language_tag.is_none());
        assert_eq!(
            vec![
                194, 163, b' ', b'a', b'n', b'd', b' ', 226, 130, 172, b' ', b'r', b'a',
                b't', b'e', b's',
            ],
            extended_value.value
        );
    }

    #[test]
    fn test_parse_extended_value_missing_language_tag_and_encoding() {
        // From: https://greenbytes.de/tech/tc2231/#attwithfn2231quot2
        let result = parse_extended_value("foo%20bar.html");
        assert!(result.is_err());
    }

    #[test]
    fn test_parse_extended_value_partially_formatted() {
        let result = parse_extended_value("UTF-8'missing third part");
        assert!(result.is_err());
    }

    #[test]
    fn test_parse_extended_value_partially_formatted_blank() {
        let result = parse_extended_value("blank second part'");
        assert!(result.is_err());
    }

    #[test]
    fn test_fmt_extended_value_with_encoding_and_language_tag() {
        let extended_value = ExtendedValue {
            charset: Charset::Iso_8859_1,
            language_tag: Some("en".parse().expect("Could not parse language tag")),
            value: vec![163, b' ', b'r', b'a', b't', b'e', b's'],
        };
        assert_eq!("ISO-8859-1'en'%A3%20rates", format!("{}", extended_value));
    }

    #[test]
    fn test_fmt_extended_value_with_encoding() {
        let extended_value = ExtendedValue {
            charset: Charset::Ext("UTF-8".to_string()),
            language_tag: None,
            value: vec![
                194, 163, b' ', b'a', b'n', b'd', b' ', 226, 130, 172, b' ', b'r', b'a',
                b't', b'e', b's',
            ],
        };
        assert_eq!(
            "UTF-8''%C2%A3%20and%20%E2%82%AC%20rates",
            format!("{}", extended_value)
        );
    }
}