use std::fmt::{Display, Formatter};
use crate::common::headers::{HeaderWriter, Writer};
use super::{Algorithm, Canonicalization, HashAlgorithm, Signature};
impl Signature {
pub(crate) fn write(&self, writer: &mut impl Writer, as_header: bool) {
let (header, new_line) = match self.ch {
Canonicalization::Relaxed if !as_header => (&b"dkim-signature:"[..], &b" "[..]),
_ => (&b"DKIM-Signature: "[..], &b"\r\n\t"[..]),
};
writer.write(header);
writer.write(b"v=1; a=");
writer.write(match self.a {
Algorithm::RsaSha256 => b"rsa-sha256",
Algorithm::RsaSha1 => b"rsa-sha1",
Algorithm::Ed25519Sha256 => b"ed25519-sha256",
});
for (tag, value) in [(&b"; s="[..], &self.s), (&b"; d="[..], &self.d)] {
writer.write(tag);
writer.write(value.as_bytes());
}
writer.write(b"; c=");
self.ch.serialize_name(writer);
writer.write(b"/");
self.cb.serialize_name(writer);
if let Some(atps) = &self.atps {
writer.write(b"; atps=");
writer.write(atps.as_bytes());
writer.write(b"; atpsh=");
writer.write(match self.atpsh {
Some(HashAlgorithm::Sha256) => b"sha256",
Some(HashAlgorithm::Sha1) => b"sha1",
_ => b"none",
});
}
if self.r {
writer.write(b"; r=y");
}
writer.write(b";");
writer.write(new_line);
let mut bw = 1;
for (num, h) in self.h.iter().enumerate() {
if bw + h.len() + 1 >= 76 {
writer.write(new_line);
bw = 1;
}
if num > 0 {
writer.write_len(b":", &mut bw);
} else {
writer.write_len(b"h=", &mut bw);
}
writer.write_len(h.as_bytes(), &mut bw);
}
if !self.i.is_empty() {
if bw + self.i.len() + 3 >= 76 {
writer.write(b";");
writer.write(new_line);
bw = 1;
} else {
writer.write_len(b"; ", &mut bw);
}
writer.write_len(b"i=", &mut bw);
for &ch in self.i.as_bytes().iter() {
match ch {
0..=0x20 | b';' | 0x7f..=u8::MAX => {
writer.write_len(format!("={ch:02X}").as_bytes(), &mut bw);
}
_ => {
writer.write_len(&[ch], &mut bw);
}
}
if bw >= 76 {
writer.write(new_line);
bw = 1;
}
}
}
for (tag, value) in [
(&b"t="[..], self.t),
(&b"x="[..], self.x),
(&b"l="[..], self.l),
] {
if value > 0 {
let value = value.to_string();
writer.write_len(b";", &mut bw);
if bw + tag.len() + value.len() >= 76 {
writer.write(new_line);
bw = 1;
} else {
writer.write_len(b" ", &mut bw);
}
writer.write_len(tag, &mut bw);
writer.write_len(value.as_bytes(), &mut bw);
}
}
for (tag, value) in [(&b"; bh="[..], &self.bh), (&b"; b="[..], &self.b)] {
writer.write_len(tag, &mut bw);
for &byte in value {
writer.write_len(&[byte], &mut bw);
if bw >= 76 {
writer.write(new_line);
bw = 1;
}
}
}
writer.write(b";");
if as_header {
writer.write(b"\r\n");
}
}
}
impl HeaderWriter for Signature {
fn write_header(&self, writer: &mut impl Writer) {
self.write(writer, true);
}
}
impl Display for Signature {
fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
let mut buf = Vec::new();
self.write(&mut buf, false);
f.write_str(&String::from_utf8(buf).map_err(|_| std::fmt::Error)?)
}
}