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use super::*;
use ser::text::{DnsTextData, DnsTextFormatter, DnsTextContext, next_field, quoted, parse_with};
impl DnsName {
/// Parse text representation of a domain name
pub fn parse(context: &DnsTextContext, value: &str) -> Result<Self>
{
let raw = value.as_bytes();
let mut name = DnsName::new_root();
if raw == b"." {
return Ok(name);
} else if raw == b"@" {
match context.origin() {
Some(o) => return Ok(o.clone()),
None => bail!("@ invalid without $ORIGIN"),
}
}
ensure!(!raw.is_empty(), "invalid empty name");
let mut label = Vec::new();
let mut pos = 0;
while pos < raw.len() {
if raw[pos] == b'.' {
ensure!(!label.is_empty(), "empty label in name: {:?}", value);
name.push_back(DnsLabelRef::new(&label)?)?;
label.clear();
} else if raw[pos] == b'\\' {
ensure!(pos + 1 < raw.len(), "unexpected end of name after backslash: {:?}", value);
if raw[pos+1] >= b'0' && raw[pos+1] <= b'9' {
// \ddd escape
ensure!(pos + 3 < raw.len(), "unexpected end of name after backslash with digit: {:?}", value);
ensure!(raw[pos+2] >= b'0' && raw[pos+2] <= b'9' && raw[pos+3] >= b'0' && raw[pos+3] <= b'9', "expected three digits after backslash in name: {:?}", name);
let d1 = (raw[pos+1] - b'0') as u32;
let d2 = (raw[pos+2] - b'0') as u32;
let d3 = (raw[pos+3] - b'0') as u32;
let v = d1 * 100 + d2 * 10 + d3;
ensure!(v < 256, "invalid escape in name, {} > 255: {:?}", v, name);
label.push(v as u8);
} else {
ensure!(!quoted::is_ascii_whitespace(raw[pos+1]), "whitespace cannot be escaped with backslash prefix; encode it as \\{:03} in: {:?}", raw[pos+1], name);
label.push(raw[pos+1]);
}
} else {
ensure!(!quoted::is_ascii_whitespace(raw[pos+1]), "whitespace must be encoded as \\{:03} in: {:?}", raw[pos+1], name);
label.push(raw[pos]);
}
pos += 1;
}
if !label.is_empty() {
// no trailing dot, relative name
// push last label
name.push_back(DnsLabelRef::new(&label)?)?;
match context.origin() {
Some(o) => {
for l in o { name.push_back(l)?; }
},
None => bail!("missing trailing dot without $ORIGIN"),
}
}
Ok(name)
}
}
impl DnsTextData for DnsName {
fn dns_parse(context: &DnsTextContext, data: &mut &str) -> Result<Self> {
let field = next_field(data)?;
DnsName::parse(context, field)
}
fn dns_format(&self, f: &mut DnsTextFormatter) -> fmt::Result {
write!(f, "{}", self)
}
}
impl ::std::str::FromStr for DnsName {
type Err = ::failure::Error;
fn from_str(s: &str) -> Result<Self> {
parse_with(s, |data| DnsName::dns_parse(&DnsTextContext::new(), data))
}
}
impl DnsCompressedName {
/// Parse text representation of a domain name
pub fn parse(context: &DnsTextContext, value: &str) -> Result<Self>
{
Ok(DnsCompressedName(DnsName::parse(context, value)?))
}
}
impl DnsTextData for DnsCompressedName {
fn dns_parse(context: &DnsTextContext, data: &mut &str) -> Result<Self> {
let field = next_field(data)?;
DnsCompressedName::parse(context, field)
}
fn dns_format(&self, f: &mut DnsTextFormatter) -> fmt::Result {
self.0.dns_format(f)
}
}
impl ::std::str::FromStr for DnsCompressedName {
type Err = ::failure::Error;
fn from_str(s: &str) -> Result<Self> {
parse_with(s, |data| DnsCompressedName::dns_parse(&DnsTextContext::new(), data))
}
}