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Implement canonicalization

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Rodolphe Bréard 2023-03-25 19:10:06 +01:00
parent d95daff90c
commit 38a4229fbd
2 changed files with 338 additions and 0 deletions
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337
src/canonicalization.rs Normal file
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@ -0,0 +1,337 @@
pub enum CanonicalizationType {
Relaxed,
Simple,
}
impl Default for CanonicalizationType {
fn default() -> Self {
Self::Relaxed
}
}
#[derive(Default)]
pub struct Canonicalization {
header_alg: CanonicalizationType,
body_alg: CanonicalizationType,
}
impl Canonicalization {
pub fn set_header_alg(mut self, alg: CanonicalizationType) -> Self {
self.header_alg = alg;
self
}
pub fn set_body_alg(mut self, alg: CanonicalizationType) -> Self {
self.body_alg = alg;
self
}
pub fn process_header(&self, header: &[u8]) -> Vec<u8> {
match self.header_alg {
CanonicalizationType::Relaxed => header_relaxed(header),
CanonicalizationType::Simple => header_simple(header),
}
}
pub fn process_body(&self, body: &[u8]) -> Vec<u8> {
match self.body_alg {
CanonicalizationType::Relaxed => body_relaxed(body),
CanonicalizationType::Simple => body_simple(body),
}
}
}
fn to_lowercase(c: &mut u8) {
if *c >= b'A' && *c <= b'Z' {
*c += 32
}
}
fn to_space(c: &mut u8) {
if *c == b'\t' {
*c = b' '
}
}
fn header_relaxed(data: &[u8]) -> Vec<u8> {
let mut data = data.to_vec();
// Step 1: Convert all header field names (not the header field values) to
// lowercase. For example, convert "SUBJect: AbC" to "subject: AbC".
if let Some(index) = data.iter().position(|&e| e == b':') {
data[..index].iter_mut().for_each(to_lowercase);
}
// Step 2: Unfold all header field continuation lines as described in
// RFC5322; in particular, lines with terminators embedded in
// continued header field values (that is, CRLF sequences followed by
// WSP) MUST be interpreted without the CRLF. Implementations MUST
// NOT remove the CRLF at the end of the header field value.
loop {
let last_pos = data.len() - 2;
match data.windows(2).position(|w| w == b"\r\n") {
Some(pos) => {
if pos == last_pos {
break;
}
data.remove(pos + 1);
data.remove(pos);
}
None => {
break;
}
}
}
// Step 3: Convert all sequences of one or more WSP characters to a single SP
// character. WSP characters here include those before and after a
// line folding boundary.
data.iter_mut().for_each(to_space);
while let Some(pos) = data.windows(2).position(|w| w == b" ") {
data.remove(pos);
}
// Step 4: Delete the SP character, if present, at the end of each unfolded
// header field value before its final CRLF.
//
// Note: this if from errata 5839
loop {
let pos = data.len() - 3;
if data[pos] != b' ' {
break;
}
data.remove(pos);
}
// Step 5: Delete any WSP characters remaining before and after the colon
// separating the header field name from the header field value. The
// colon separator MUST be retained.
while let Some(pos) = data.iter().position(|&e| e == b':') {
if data[pos + 1] == b' ' {
data.remove(pos + 1);
} else if data[pos - 1] == b' ' {
data.remove(pos - 1);
} else {
break;
}
}
data
}
fn header_simple(data: &[u8]) -> Vec<u8> {
data.to_vec()
}
fn body_relaxed(data: &[u8]) -> Vec<u8> {
let mut data = data.to_vec();
// Ignore all whitespace at the end of lines.
while let Some(pos) = data
.windows(3)
.position(|w| w == b" \r\n" || w == b"\t\r\n")
{
data.remove(pos);
}
// Reduce all sequences of WSP within a line to a single SP character.
while let Some(pos) = data
.windows(2)
.position(|w| (w[0] == b' ' || w[0] == b'\t') && (w[1] == b' ' || w[1] == b'\t'))
{
data[pos] = b' ';
data.remove(pos + 1);
}
// Ignore all empty lines at the end of the message body.
while data.ends_with(b"\r\n\r\n") {
let pos = data.len();
data.remove(pos - 1);
data.remove(pos - 2);
}
data
}
fn body_simple(data: &[u8]) -> Vec<u8> {
let mut data = data.to_vec();
// Ignore all empty lines at the end of the message body.
while data.ends_with(b"\r\n\r\n") {
let pos = data.len();
data.remove(pos - 1);
data.remove(pos - 2);
}
data
}
#[cfg(test)]
mod tests {
use super::*;
const HEADER_00: &[u8] = b"Accept-Language:\r\n";
const HEADER_01: &[u8] = b"Accept-Language: fr-FR, en-US\r\n";
const HEADER_02: &[u8] = b"accept-language: fr-FR, en-US\r\n";
const HEADER_03: &[u8] = b"AcCePt-LaNgUaGe: fr-FR, en-US\r\n";
const HEADER_04: &[u8] = b"Accept-Language:fr-FR, en-US\r\n";
const HEADER_05: &[u8] = b"Accept-Language : fr-FR, en-US \r\n";
const HEADER_06: &[u8] = b"Accept-Language: fr-FR,\r\n en-US,\r\n de-DE\r\n";
const HEADER_07: &[u8] = b"Accept-Language: fr-FR,\r\nen-US\r\n\r\n";
const BODY_00: &[u8] = b"\r\n";
const BODY_01: &[u8] = b"Hello, World!\r\n";
const BODY_02: &[u8] = b"Hello, World \t!\r\n\r\n\r\ntest \r\nbis\r\n\r\n";
#[test]
fn header_relaxed_01() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_01),
b"accept-language:fr-FR, en-US\r\n"
);
}
#[test]
fn header_relaxed_02() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_02),
b"accept-language:fr-FR, en-US\r\n"
);
}
#[test]
fn header_relaxed_03() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_03),
b"accept-language:fr-FR, en-US\r\n"
);
}
#[test]
fn header_relaxed_04() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_04),
b"accept-language:fr-FR, en-US\r\n"
);
}
#[test]
fn header_relaxed_05() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_05),
b"accept-language:fr-FR, en-US\r\n"
);
}
#[test]
fn header_relaxed_06() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_06),
b"accept-language:fr-FR, en-US, de-DE\r\n"
);
}
#[test]
fn header_relaxed_07() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_header(HEADER_07),
b"accept-language:fr-FR,en-US\r\n"
);
}
#[test]
fn header_simple_00() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_00), HEADER_00);
}
#[test]
fn header_simple_01() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_01), HEADER_01);
}
#[test]
fn header_simple_02() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_02), HEADER_02);
}
#[test]
fn header_simple_03() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_03), HEADER_03);
}
#[test]
fn header_simple_04() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_04), HEADER_04);
}
#[test]
fn header_simple_05() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_05), HEADER_05);
}
#[test]
fn header_simple_06() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_06), HEADER_06);
}
#[test]
fn header_simple_07() {
let c = Canonicalization::default().set_header_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_header(HEADER_07), HEADER_07);
}
#[test]
fn body_simple_00() {
let c = Canonicalization::default().set_body_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_body(BODY_00), BODY_00);
}
#[test]
fn body_simple_01() {
let c = Canonicalization::default().set_body_alg(CanonicalizationType::Simple);
assert_eq!(&c.process_body(BODY_01), BODY_01);
}
#[test]
fn body_simple_02() {
let c = Canonicalization::default().set_body_alg(CanonicalizationType::Simple);
assert_eq!(
&c.process_body(BODY_02),
b"Hello, World \t!\r\n\r\n\r\ntest \r\nbis\r\n"
);
}
#[test]
fn body_relaxed_00() {
let c = Canonicalization::default().set_body_alg(CanonicalizationType::Relaxed);
assert_eq!(&c.process_body(BODY_00), BODY_00);
}
#[test]
fn body_relaxed_01() {
let c = Canonicalization::default().set_body_alg(CanonicalizationType::Relaxed);
assert_eq!(&c.process_body(BODY_01), BODY_01);
}
#[test]
fn body_relaxed_02() {
let c = Canonicalization::default().set_body_alg(CanonicalizationType::Relaxed);
assert_eq!(
&c.process_body(BODY_02),
b"Hello, World !\r\n\r\n\r\ntest\r\nbis\r\n"
);
}
}

1
src/main.rs
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@ -1,3 +1,4 @@
mod canonicalization;
mod entry;
mod handshake;
mod logs;